OF THE IRew l^orK State Deterinar^ College AT (Tornell XHntversit^ Cornell University Library RB 145.G89 The biology of the blood-cells with a gl 3 1924 000 893 929 Date Due p^k k i im '^ Library Bureau Cat. No. 1137 BIOLOGY OF THE BLOOD-CELLS Cornell University Library The original of this bool< is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924000893929 THE BIOLOGY OF THE BLOOD-CELLS WITH A GLOSSARY OF HEMATOLOGICAL TERMS : FOR THE USE OF PRACTITIONERS OF MEDICINE BY O. C. GRUNER, M.D. Lond. A uthor of *^ Studies in Punciure-fiuids^^ ; ** A Code-system for ike Hospital PatkologisV^ : Paikologisi to the Royal Victoria Hospitalt and to the Maternity Hospital^ Montreal; Assistant Professor of Pathology^ M'*Gill University^ Montreal^ etc.. Late Clinical Pathologist^ General Infirmary at Leeds, WILLIAM NEW YORK: WOOD & MDCCCCXIV COMPANY ■^^^v.' NVS^'^'i PREFACE This work is intended to serve as a companion to any of the larger text-books on Hsematology. Special stress has been laid upon the close relationship between changes in the blood-forming organs and the blood picture as the clinician sees it, and also upon the minute morphology of the various blood-ceUs, whether sessile or free-floating. Above all, the attention of the student has been directed to the fundamental unity of design which is the basis of haemopoiesis from birth to death throughout the animal kingdom. The names of haematologists whose works have been consulted appear in a special index, but the author wishes here more particularly to acknowledge the great debt which he owes to Pappenheim, whose writings are in so many ways an inspiration. O. C. GRUNER. Montreal, Octobir, 1913. CONTENTS chap. pace Introduction. ...... i I. — On the Primordial Blood-cell .... 7 Section I. — The Primordial Cell, 8 ; Section II. — The Primordial Cell (continued), 25; Section III. — The Primordial Cell {concluded), 37. II. — On the Red Blood-cell . . . . .44 Section I. — The Bone-Marrow as a Red-cell Factory, 45 ; Section II. — The Erythroblastic Line of Development, 53 ; Section III. — The Life History of the Red Blood-corpuscle in the Blood-stream, 69 ; Section IV. The Metaplastic, Metahyperplastic, and Aplastic Phenomena of Erythro- poiesis, 100. III. — On the Lymphocyte . . . . . .110 Section I. — The Factories of the Lymphocyte, in ; Section II. — The Lymphoblastic Line of Development, 124 ; Section III. — The Lymphocyte of the Blood-stream, 131 ; Section IV. — The Fate of the Lymphocyte, 148. IV. — On the Large Mononuclear Leucocyte . . . 155 Section I. — On the Structure of the Pulpar Tissue, 156 ; Section II. — On the Large Mononuclear Leucocyte of the Blood-stream, 171 ; Section III. — The Pulpar Cell and its Cytoplasias, 189. V. — On the Neutrophile Leucocyte .... 194 Section I. — Bone-marrow as a White-cell Factory, 195 ; Section II. — The Life-history of the Neutrophile Leucocyte up to the time of its Birth into the Blood-stream, 203 ; Section III. — The Life-cycle of the Blood-mature Leucocyte, 213 ; Section 7F.— The Cytoplasias of the Leucopoietic Tissues, 233. VI. — On Certain Phlogocytes ..... 243 Section I. — Aberrant Abortive Heemopoiesis, 244 ; Section II. — The Eosinophile Cell, 249 ; Section III. — The Mast Cell, 259 ; Section IV. — The Plasma Cell, 266 ; Section V. — The Clasmatocyte, 278 ; Section VI. — The Cytoplastic Inter-relations between the various Phlogocytes, 279. VIU Contents VII. — The Cytoplastic Phenomena of Blood-forming Tissues . Section I. — ^Metaplasia in General, 285 ; Section II. — Special Examples of Metaplasia in HEemopoietic Tissues, 298 ; Section III. — Survey of the Hyperplastic, Metaplastic, Metahyperplastic, and Allied 'Processes in the Pulpar and Follicular Tissues, 311. Abbreviations Employed . References to the Literature Glossary of Hematological Terms General Index Index of Diseases Referred to . Index of Animals ,, ,, . Index of Authors ,, ,, . PAGE 284 321 322 337 371 382 385 387 LIST OF COLOURED PLATES I. — The Primordial Blood-cell II. — The Red Blood-cell III. — Author's Scheme of Lymphogenesis IV. — ^Mononuclear and Certain other Blood-cells V. — The Relation between Pulpar Tissue and Venous Channels .... VI. — The Large Mononuclear Leucocyte VII. — Phlogocytes ..... oing page lO „ 76 .. 126 tt If 134 3 158 „ 190 j» i» 250 LIST OF ILLUSTRATIONS FIG. I.- 2.- 3-- 4-- 5-' 6.- 7-—'- 8.- 9-- 10. 31. 12. I3-- 14.- 16.- 17, i8.- 19.- 20.- 21. 22. 23- 24.- 26. 27. 28. 29. 30- T.S. of Bone, showing Trabecule, Marrow Tissue, Blood- vessels and Fat Spaces . . . facing page •Photograph of Three Follicles and Spleen-pulp Fragments of Trabeculse . . . ,, ,, •A Single Follicle showing Germ-centre Cells ,, ;, -Diagram of Structure of the Lymphoidocyte ■Diagram Representing Ontogeny and Phylogeny in a Cell Series ■Mast-cell Lymphoidocyte — Leucoblast . — Rieder Cell . — Leucosarcoma CeU . —Spermatogenesis — Diagram showing contrast between Lymphoblast and Myelo blast — Scheme of Cell Descent — Leukemic Proliferation —Rate of Proliferation ; (a) Normal ; (6) Hyperplasia — Diagram representing Hyperplasia, Metaplasia and Anaplasia — Normal Bone-marrow . . . facing page — Bone-marrow showing Erythroblastic Reaction ,, ,, — Pigment in Bone-marrow . . . ,, .. — ^Transverse Section of Primitive Blood-vessel — Longitudinal Section of Primitive Blood-vessel — Lymphoid Erythroblasts — Diagram of the Megaloblast Forms. — Schilling's Conception of a Red Cell — Platelets escaping from Red Blood-corpuscles — A Demi-lune Body .... — Blood-supply of Lymph Node . . facing page — ^Malpighian Folhcle in the Spleen . . „ „ — A View of the Arterial Supply of the Spleen ,, 16 19 22 25 32 38 39 39 40 44 45 45 54 55 60 62 70 86 88 "3 113 120 List of Illustrations xi FIG. PAGB 31. — Centre of Malpighian Follicle . . facing page 120 32. — Anomalous Shape of Malpighian Follicle . ,, ,, 121 33. — ^Edge of a Capillary, showing Discharge of Lymphoid Cells from an adjacent FoUicle into the Lumen facing page 121 34. — Central Part of a Lymphoid Follicle . „ ,, 129 35. — Splenoid Metaplasia of Lymph-node . ,, „ 156 36. — Transverse Section of a Pulp Cord . ,, ,, 156 37. — Fragments of Trabeculae . . . ,, ,, 157 38. — Splenic Pulp Tissue, showing Fibrosis . ,, ,, 157 39. — Splenic Pulp Tissue of Puppy, showing Megakaryocytes facing page 161 40. — The Two Forms of Monocjrte .... 175 41. — Diagrammatic, showing Morphological Differences between Lymphatic Monocyie and Leucocytoid Lymphocyte . 176 42.- — Phagocytosis in Lymph-channel of a Lymph-node /acjM^ page 183 43. — Splenic Tissue in a case of Death from Infection by Bacillus Aerogenes Capsulatus . . . facing page 192 44. — Splenic Pulp in a state of Myeloid Metaplasia ,, ,, 192 45. — Chart representing Inter-relations between Follicles and Pulpar Tissue ...... 193 46. — Graphic Record of the Cell-Formula of the Bone Marrow . 196 47. — Atrophic Marrow .... facing page 198 48. — Gelatinous Degeneration . . . ,, ,, 199 49. — Degeneration of Marrow Cell . . ,, ,, 199 50, 51. — ^Marrow Film . . . . ,, ,, 200 52. — Diagram of Structure of the Lymphoidocyte . . 203 53. — The Promyelocyte ...... 206 54. — Diagram of some of the Cells of the My eloic Series . . 210 55. — Leucocytes showing Amoeboid Movement . . . 213 56. — Neutrophiles from a Case of Acute Pneumonia . . 214 57. — Graphic representation of Arneth's System. . . 215 58. — Caryorrhectic Leucocytes in an Inflammatory Area facing page 217 59. — Curves showing efiect of certain Organisms on the character of the Cells of the Exudate . . . .216 60. — Chart illustrating Arneth's Method . . . .219 61. — The Neutrophile Leucocyte . . . .221 62. — Lymphocytes in the Breast. . . facing page 244 xii List of Illustrations FIG. PAGE 63. — Adrenal Medulla, showing Small Round-celled Infiltration facing page 244 64, 65. — Views in a Zone of Chronic Inflammatory Cell Infiltration facing page 245 66. — Chronic Inflammatory Cell Infiltration in a Case of Gonor- rhoeal Salpingitis . . . facing page 247 67.- — Portion of a Capillary Wall in an Inflammatory Area in a Case of Chronic Interstitial Appendicitis facing page 247 68. — Portion of an Intestinal Lymphoid Follicle, from a Case of Typhoid Fever .... facing page 273 69A & B. — Diagrams to show the Double Action of Noxious Agents on Tissues and Blood-forming Organs . . 280, 281 70. — Chart representing the Inter-relations between the Phlogocytes 283 71. — Steric Chemical Interchanges .... 295 72. — Splenic Pulp in a state of Myeloid Metaplasia facing page 302 73. — Splenic Tissue in a case of Acute Lymphatic Leukaemia facing page 302 74. — Mononucleate and Binucleate Forms from the Pulp Tissue of the Spleen in a case of Chronic Lymphatic Leuksemia facing page 305 75 — Germ-centres with well-marked Endothehoid Cells ,, ,, 305 BIOLOGY OF THE BLOOD-CELLS INTRODUCTION, THE classical figure, devised by Huxley, of a hypothetical Martian coming to this earth and making his investigations into the life-history of mankind by parahuman methods, is so significant that it should be ever present before the investigator. We are too apt to follow the stereotyped lines of presentation of ideas, and fail to transfer ourselves to an imaginary higher plane of life, in order to study the appearances of things from a stand- point as nearly extrahuman as is possible. This objection applies with special force to the blood-cells. These cells, circulating blindly through the blood-vessels at the microscopic rate of thirty miles an hour, are usually only referred to during that stage of their existence ; they are assiduously enumerated, and percentages are worked out (" a white-cell formula"), just as the number of fat globules might be estimated in a drop of milk to ascertain its hygienic value. If we reflect that these circulating ceUs must be manufactured, must pass through various phases of life during which they linger in the bjrways and alleys of the body, in order to fulfil definite purposes before they succumb to the death common to all cells, we see that the ordinary clinical conceptions are quite inadequate. Let the reader imagine himself to be transported by magical means to the centre of an absolutely new city, inhabited by beings of a different and hitherto unknown race. How would he proceed to find out the story of these beings ? He would not be content to stand at the street comer or in the gateway, and collect together five hundred of the bustUng, active, hurrying toilers as they passed, and, mingling them with a few of the indolent loungers in the I 2 Biology of the Blood-cells vicinity, proceed to classify all these persons into percentages according to their types. From a convenient vantage-ground he would carefully note the peculiarities of each passer-by, dividing them into as many different types as he could ; and he would not confine himself to a short period of the day, but would observe the different features about the people— at this time, at that ; to- morrow ; a month hence ; by day ; by night. Furthermore, it is not to be conceived for an instant but that he would look at the buildings, the roads, the material transported along the streets, and that he would feel a desire to ascertain the processes at work within those buildings ; to see the factories ; to see where the people came from ; where they went ; how they died ; why they died ; and what part each played in the whole fabric of life. It is evident, therefore, that a clear idea of the blood-cells predicates more data than are supplied by taking a single drop of blood, drying it, and subjecting it to a microscopic examination. Maybe this is the only feasible procedure in a patient, but it is not the only method by which the subject can be studied. The structure of the blood-cell-forming organs is now sufficiently far advanced to enable definite ideas to be maintained. A knowledge of the structure of these blood-cell factories is all essential to a correct appreciation of the significance of the presence of the various changes found in blood films both in health and disease. The Factories of the Blood-cells are of two varieties — those which are in constant requisition, and those which are only occasionally brought into action. The latter include the peri- vascular tissues in every part of the body, while the former embrace the bone-marrow, the spleen, and the lymphatic system of formative tissues. There is a remarkable family resemblance of structure exhibited by each and all of these tissues which can only have one significance, namely, that the process of mamifac- ture is fundamentally the same in each case. Thus, to sketch out the characters of each factory broadly, we have : — In the bone-marrow, intense vascularity — a veritable angioma, with numbers of formative cells completely filling up the inter- vascular spaces, save where fat-cells are interpolated in numbers varying with the degree of activity of blood-cell formation (Fig. i). •' In the bone-marrow, intense vascularity . . . -with numbers of formative cells completeh- fillinL' up the vascular spaces" (p. 2). 1 j h F!c. I.— T.S. OF Bone, showing (a) the trabeculie ; (6) the marrow tissue; (c) the deeplv congested blond-\-c^^cls ; and (./) the fat spaces. The marrow tissue is seen to consist of dcnselv-packcd cells which stain deeply. " ' (Oc. 4, Zeiss Apuchrom. 4 mm.). " In the spleen, the microscope re\-eals two series of tissues — the w^ell-known ::\Ialpighian l:tody and the pulp " (p. 3). Fig. 2. — The photograph shows three follicles, which appear as darker-coloured areas. \'\^ithin each is an indication of the artery which traverses it. The remainder of the picture is formed of spleen- pulp. (Oc. 2, Zeiss Apochrom. 4 mm,). /i'acc /, 3] the pulp tissue . . . consists ot bkind-chauuels enclosed by man}- ^-arictics of formative cells " (p. 3). F)\'. ■. — The phot;inciits of traheciiLf i\-ertical) and a nninticr of elor spaces marked o\it by the dark nuclei of endothelial cells. The inter\"cninL; cells constitute the s pulp tissue. long a ted iplenic (Oc. 4. Zeiss Apochrom. 4 mm.). is alwa>-s held to be the most characteristic feature of the "... the .. . lymphatic follicle lymph-node" (p. ^). Fig^ +.— A SiN-GLE Follicle showing the well-marked germ-centre cells, enclosed b\- a dark- coloured dense wall oi lymphucyte-like cells. {Oc. 4, Apochrom. 4 mm.). Introduction 3 The intervascular cells are nearly all free-floating, and vary much in size • according as they belong to one or other generation of development. The only detail that is readily made out amongst these cells is that some contain haemoglobin and others do not. In other words, the usual finding is one of red-cell formation with a varying amount of white-cell formation. In the spleen, the microscope reveals two series of tissues — the weU-known Malpighian body and the pulp. The former {Fig. 2) is a well-defined structure whose architecture is intimately con- nected with an arterial channel, while the pulp tissue [Fig. 3) is quite heterogeneous, and consists of blood-channels enclosed by many varieties of formative cells, whose nature is masked by the mcirked intermingling with cells of definitely connective-tisSue type — certainly not specific blood-forming cells. In the lymphatic system the structure is remarkably similar to that of the spleen. The chief difference lies in the " Malpighian body " being peripheral, while the pulp is central in situation. The Malpighian body here assumes the simple title of lymphatic follicle {Fig. 4), and is always held to be the most characteristic feature of the lymph-node, in spite of the fact that certain mesen- teric lymph nodes never contain a follicle from the beginning to the end of life. The pulp tissue of the lymph-node is, one might say, absurdly like the pulp tissue of the spleen {see p. 156, Fig. 35), but the ordinary picture is modified by the conspicuous character of the lymphatic channels. The reserve factories require no special description, since they consist of the ordinary connective tissues permeating the body, which only becomes similar in character to the pulp tissue of the named organs when such time arises that their activity is demanded. The so-called perivascular lymphoma, which is dealt with in Chapter VI., is understood to belong to the lymphatic system. The present series of factories belongs sometimes to the lymphatic and some- times to the opposite series of cell-formation, the myeloid series. The latter term is convenient as implying the formation of cells characteristic of the bone-marrow, although it must always be remembered that cells belonging to the lymphatic series may, on occasion, be made there also. 4 Biology of the Blood-cells To be more precise, we should describe three kinds of blood- cell factory : that concerned, (i) With the manufacture of red cells ; (2) With the production of polymorphonuclear leucocytes ; (3) With the production of mononuclear cells. But, even so, the outstanding feature of the histology of the tissue is that there is much similarity of structure between one and any other. This consideration leads to the problem of the real origin of the various types of circulating blood-cells. Are they all one, or have they different parents ? It also necessitates the grouping of the subject matter according to the kind of blood-cell manufactured, and not according to the organs in which such processes occur. This is perhaps the most important feature in the problem at issue. The bone-marrow does not make only red cells and neutrophDes, the lymph-node does not make only lymphocytes, the spleen does not only destroy. Certain cells in the bone-marrow make red cells, and others make the myeloid series of cells, but sometimes the same series of cells makes lymphocytes instead. The pulp tissue of the lymph-node and of the spleen are usually concerned with the lymph follicles with which they are associated, but sometimes they make neutrophiles (the myeloic series), and at other times each of them makes large mononuclear leucocytes. Occasionally, the spleen makes red cells in large numbers. Even though the site of formation of any of these cells may be variable, the final products (the " blood-mature " cells) are fairly easily classified. The well-known cell formula : — Red cells . . . about 5,000,000 per c.mm. Haemoglobin . . 95 to no per cent White cells . . . 5 to 8, and notmore than 10,000 per c.mm. Polymorphonuclear leucocytes about 70 per cent Lymphocytes . . . ,,20 Large mononuclears . . „ 8 Eosinophile leucocytes . ,, i ,, or more Mast cells .... „ i „ or less is regarded as a list of the cell forms with their average normal numbers and proportions. As a rule, maximum and minimum limits are assigned for the leucocyte percentages. They have been omitted above for the sake of simplicity. Introduction 5 The study of blood films is misleading to this extent, that the cells are seen in an artificial condition. The cell forms are normally in motion, the granules within them are moving, the cell composition is changing, and the structural characters differ with the progress from youth to old age. Further, a cell-count only represents the state of the peripheral blood at the particular moment of collecting the material. The wide daily variation in the total white cell-count requires to be borne in mind. The fact of such variation being much exaggerated in certain diseases, as shown by the observations of Thomson,* Marlin,t and others, should render the practice of paying slavish devotion at the feet of " exact " total cell-counts a matter of history. A very low total white-count, or a very high one, may be of definite value, but it need not be correct " to the fourth figure." We suggest that the preliminary blood examination should lie in a study of films, the erythrocytometer being only called in later, and then, preferably, only after a hsemoglobin estimation (correct to a multiple of five) has been made. In surgical cases, however, a rapid white-count correct to the nearest thousand should be run through two to four times a day in difficult cases ; the red cell-count is a luxury in surgical work, but a necessity in chronic medical cases. The exact nomenclature of the cell-forms varies considerably. Many writers call the large mononuclears "large lymphocytes." Others add the English term, " hyaline leucocyte," which is really only a form of lymphocyte. I For descriptive purposes it is, however, much more satisfactory to divide the blood-ceUs into primordial, red, lymphocytic, mono- cytic, neutrophihc and phlogocytic forms. The last named include any of those characteristic of non-suppurative inflammatory oell infiltration. The primordial cell is understood to be the parent form of any of the other blood-cells, and it only appears in the blood stream under peculiar pathological circumstances. The word " primordial " conveniently expresses the simple idea that this cell is an ancestor several generations back in the line of development, and does not represent a morphological type, although some forms of primordial cell are actually synonymous with Pappenheim's lymphoidocyte. The term " monocyte," introduced by Pappenheim, is used in a *B.M.J., 1911, p. 1586. ■\ Journal of Clinical Research, 1912, p. 43. X To avoid repetitions and to facilitate reference, the meaning of any term used in hsematology will be found stated in the glossary at the end of this book. Under each terra is given a list of other words which have been employed to designate the same cell. 6 Biology of the Blood-cells morphological sense. It is so convenient as to deserve universal adoption. The life-history of each one of these main groups of cells will be traced out, noting the changes which occur from the time of their birth to that of their death, and the effects upon them which pathogenic or other influences produce. Our opening remarks indicate the importance of a study of the tissues in which each is formed,* both in regard to the ante-natal processes for each cell, and in regard to the mode in which the blood-cell formula reflects the morbid changes (anaplasias, metaplasias, hyperplasias, etc.) at the root of the so-called " diseases of the blood." We shall thus find that each " blood-disease," at some stage in its course, is the outward evidence to us of a tragedy in the life- history of the particular portion of the hjematopoietic system, and we shall dimly appreciate the fact that orderly blood formation demands constant single-hearted co-operation on the part of the other tissues of the body,t as well as co-operation with the brain, which should see that deleterious agents are not admitted by care- lessness in diet and general hygiene. Withdraw such influences, and the formative blood-cells are stranded ; they make desperate attempts to breed true and follow up definite harmoniously apportioned (methodised) sequences of differentiation ; fail ; and are irretrievably lost (because destroyed by the harmful agent) or merely maimed until such time as better conditions prevail. The individuals of the army which fight such incessant warfare under these conditions are at the same time inconstant as entities ; they are ever changing, ever moving about and ever reproducing, not working together for individual purposes, but all subserving com- mon necessities, while each still acts for himself where nutrition is concerned. * The various hajmatopoietic tissues whicli are concerned witli tlie production of each type of blood-cell do not correspond to organs — tissue and organ are not equivalent or co-significative. The tissue which makes a lymphocyte, for instance, is not the whole of a lymphatic gland, nor is a lymphatic gland the only structure in the body which makes lymphocytes. This fact renders it logical to preface a description of any given order of blood-cells by an account of the corresponding formative tissue, and to correlate aberrations in the particular cell genealogy with metaplastic, hyperplastic, and allied changes in that tissue. t Epigenetic stimuli. CHAPTER I. ON THE PRIMORDIAL BLOOD-CELL. Section I. — ^The Primordial Cell: Where met with — Morpho- logy — Comparative cytology — Chemical characters — ^The subsequent history and fate of the primordial cell : Phases in its life : Old age : DifEerentiative divisions : Signs of ontogenetic and phylogenetic develop- ment : Abnormal entry into the blood-stream — Differential diagnosis : Typical and atypical forms : The lymphoblastic macrolymphocyte : The leucoblast : The Rieder cell : The leucosarcoma cell — ^The death of the primordial cell : Degeneration forms : Changes in (a) nucleus, (&) cell-body : Irritation forms. Section II. — Evidence pointing to the existence of a mother-cell for the adult blood-cells — ^The arguments in favour of (a) dualism, (6) unitarianism in haematology — ^Werzberg's and EUermann's experiments. Section III. — Cytometaplasias of the Lymphoidocyte. Biology of the Blood ■fe- -. &*' .^ Biolo^v ol Blood-cells The Primordial Cell 11 forms are seen in tinea vulgaris, cobitis fossilis, and characteristically large cells are seen in anguilla fluviatilis, whose cell-body tends to increase in size and diminish in basophilia as the cell ages and differentiates. In this class of animals, the lymphoidocyte is present in much smaller number than is usual with the amphibia. In the amphibia, tjrpical large lymphocytes or myeloblasts are met with, whose cell body is broader and more pure blue* than in man. The nuclear network is very delicate. Transitional forms to large lympholeucocytes and small lymphocytes can be seen. The astrosphere is well seen in the salamander lymphoidocyte. Vacuoles are frequent in the cell body in siredon. Nucleoli are absent in siredon. These cells are numerous in the blood of the newt, triton, and the Mexican axolotl (siredon pisciformis) and in young frogs, but though present are rare in other amphibians. In the reptiles, large lymphocjrtes occur in varying numbers in the circulating blood. They are large round basophile cells with an extremely fine azure granulation, a round central nucleus with delicate nuclear net- work and one nucleolus. In the lizard (lacerta viridis) and in gongylus ocellatus the nuclear structure is more myeloblastic. Nucleoli are absent in the tortoise-lymphoidocyte. These cells are numerous only in algiroides nigropunctatus, the scincoid lizard, and are not found at all in ophiosaurus acanthodactylus. Microlymphoidocytes with intensely basophile border occur in algiroides and in platydactylus mauritanicus (with azurophile granules). Transitional forms to amphochromophile myeloblasts are seen in some of this group of animals, and apparently take the place of the missing poly- nuclear leucocytes ; such cells have a dull violet granulation. True myelocytes are not found in agama inermis. In the chameleon, the lymphoidocyte has a relatively large cell body and presents a number of vacuoles, especially towards the periphery of the cell. A feebly oxyphile area may be found in the middle of the cell near the nucleus, which is the position in which the eosinophilic bodies of the descendant cells will appear. (Reptile blood-cells are largely eosinophilic.) In the birds, lymphoidocjrtes or primordial cells are not present in the circulating blood except under abnormal (experimental) conditions. The size of the cell is typically large, its cytoplasm has a peculiar radial structure, while the nucleus stains feebly and shows a tendency to myelocytar markings. " Irritation " forms occur here with a strongly basophile peripheral zone. 3. Chemical Characters. — Observations upon the chemistry of the primordial cell, as an individual, depend on the careful study of preparations stained by different dye combinations. The differ- ences in morphology are largely dependent on differences of chemical structure of the cell as a whole, and the variations in • Panoptic stain. 12 Biology of the Blood-cells form which are observed during the course of the life of the cell are also dependent upon intra- and intermolecular changes, taking place within either nucleus, or cell-substance, or both. To a large extent, a description of the chemistry of this cell will be that of any other, but the subtle differences of morphology which obtain in the blood-cell series, to be set forth in detail, must surely mean equally subtle differences in the cytochemical arrangements, which may be read by him who understands. Of all the microchemical work which has been done in tissues, there is no one who has been so able an exponent of chemical details based on dye-chemical considerations as Pappenheim, and whatever there is to be said about the chemistry of blood-cells is owing to his expositions. It has long been known, of course, that the nuclear substance is com- posed of nucleic acid : but such a statement practically covers all that can be said in the way of correlation between histology and chemistry. The wealth of information about the chemistry of cells (biochemistry) is only applicable to a general concept of " protoplasm," using that term in the sense of any matter which bears the phenomenon of life ; in the sense of a collection of mole- cules into a giant molecule with a number of side chains of unknown composition (beyond the detecting of amino, hydroxyl, or carboxyl groups), whose stereochemical position and exact modes of inter- action are not loiown. Not only is our knowledge of this point general in the above-indicated manner, but it is rendered more abstract still, when we reflect that space has to be found mthin the complex molecules in which to provide enzymes with a sphere of activity. The watery constituents, the salts, the ionic concentra- tion of hydroxyl groups, and the surface tension phenomena pro- duced by the colloidal substances, are all taken into accoimt in the ordinary description of the chemical composition of cells in general. But it is not in this way only that the chemistry of cells is to be discussed in relation to blood-cells ; we wish to learn if chemico-structural differences correspond to differences in morphology. We have nuclear matter, in which are chromatin, parachromatin, chromosomes, etc. These portions react differently towards different stains, such as azure dyes or methyl-green and pyronin. On the one hand, we find that azure will stain a portion The Primordial Cell 13 of the substance red (prochromatin), while the remainder is baso- phile and stains with methyl-green (metachromatin). These two dyes have been combined by Pappenheim into a methyl-green- Giemsa-aurangeate.s ai;d enable the demonstration that some nuclei contain more prochromatin (stain red), others more meta- chromatin (stain greener), while others contain as much of one variety of chromatin as of the other, and stain blue-violet. Again, using methyl-green and pyronin, it is found that both dyes will affect corresponding parts of the nucleus as long as it is in the resting stage, while chromosomes take up methyl-green alone (basichromatin) ; from this it is deduced that the chromosome is more nearly pure nucleic acid than is resting nuclear matter which contains nucleoproteid in considerable amount. The same is shown by Heidenhain's observations : (i) That the resting nucleus contains chiefly oxychromatin ; (2) That the chromosomes in the intestinal epithelial cells of the salamander are the expression of regeneration of basichromatin in the nucleus. The changes of staining reaction in the cell body, the initial basophilia (indicating the presence of organic acid) followed by oxyphilia as the cell grows older or differentiates (that is, oxyphilia increasing with each successive generation), should be translated in terms of microchemical reactions initiated from the nucleus. Metabolic changes in the nucleoproteid lead to the discharge into the cell body of basic substances, which accumulate in the iirst place in the astrospheric region ; deposition of paraplasm in the interspongioplastic network accounts for the increasing oxyphilia of cell body which is seen as we pass from lymphoidocyte to finished polynuclear leucocyte. Prolongations of the abasichrom- atic nuclear network into filaments, which end in the cytoplasm, were observed by Knoll. ^ Changes in the nuclear chromatin, leading to rearrangement of molecules, account for the morpho- logical changes in the nuclear network, which we should be careful not to lay too much stress on as permanencies. They are transient stages, and may represent part of a definite cycle of intemuclear molecular changes which will return to the same phase at some unknown interval. In other words, to be less abstract, fine lepto- chromatic network aggregates into larger masses, either during the 14 Biology of the Blood-cells life of the cell as an individual or during succeeding generations. These masses become increasingly aggregated as the nucleic acids of the cell increase towards the formation, for instance, of the typical myelocytar nucleus. Anaplasia, then, consists in the changes which lead to the breaking up of such aggregations back into the stage of fine leptochromatism — reversionary in one sense, progressive in the other. Just as a person standing outside a circular track in which a body revolves would regard that body as progressing as long as it is advancing towards him, coming nearer and nearer to his eye, and as regressing because, after passing the nearest point, it now steadily recedes farther and farther from him. The body itself, then, is only moving in a certain cycle, progressing in a sense, but always moving in the same direction. This idea is very well expressed in the phenomenon of leucocytosis to be discussed later — extreme leucocytosis, to speak paradoxically, is leucopenia. The reader is referred to later pages for the explanation of this paradox, which, like many others, is due to the errors of language, different names burdening one single idea because our minds fail to grasp the rock-bottom truth at the outset. In discussing the chemistry of the cell we have always to divide up the substances into basophile and oxyphile, just because our only means of staining cells is by using basophile and oxyphile dyes. The basophile constituent of the nucleus is due to purin compounds or to nucleic acids ; that of the ceU body is due to lecithin com- pounds of protein with nucleohiston. Glycerophosphoric acid plus various fatty acids plus cholin, therefore, represent possible constituents of the basophile substance of the cytoplasm. Break- down during metabolic activity would lead to the appearance of acidophile bodies in the paraplasm, or it might lead to the appear- ance of metachromatic bodies in the spongioplasm, starting with the assumption (borne out by oil-immersion histology) that the basophile constituent of cell-body is largely dependent on the spongioplasm. The appearance of mast-ceU granules on the spongioplastic network and of eosinophile granules in the para- plasm, constitute examples of these different forms of activity, and, as we shall see later, they are evidences of functional state and not of hard-and-fast distinctions from certain o'ther blood-cells. The Primordial Cell l& From all these considerations, the view already expressed that cell substance is merely a giant living molecule is seen to be quite fallacious, and proves that biochemistry must be intimately associ- ated with microchemistry if errors of popular conception are to be avoided.io 4. Subsequent History and Fate of the Primordial Cell : Phases in the Life of the Primordial Cell. — The primordial cell may exhibit purely nutritive or purely reproductive activity, like any other ceU. When reproduction takes place the result may be two or more* similar cells, or the progeny is more or less differentiated. The latter result (less differentiated) is indicated by the term anaplastic, and the former (more differentiation) by the term metaplastic. If we speak of nutrition and reproduction going on hand in hand, so as to introduce the idea that these two processes may go on at different rates, we refer to the effect on the tissue resulting from nutritive activity of one group of cells, and reproductive activity of another group of cells. The cells of the tissue may, in other words, be divided into two groups according as they present the one or the other variety of activity, classifying them regardless of their relative position in the tissue. In any such group of cells, too, sub-groups may be arranged according to the effect of the reproductive activity itself, whether with or without differentiation. Differentiation, however, may proceed at different rates in different cells. The net result — the degree of differentiation of the tissue — would depend on the relative proportions between individuals with slow rate of differentiation, individuals with rapid rate, and individuals either not differentiating at all or only presenting nutritive activity. Old Age. — From the above remarks it is seen that a cell may grow old without further change ; it may grow old and at the same time undergo changes leading to division without differentiation, or it may grow old and at the same time differentiate, so that its progeny are provided with new characters. Any of these variants Meristematic proliferation (merozoites), if a cluster of microlymphoidocytes, e.g., is produced. 16 Biology of the Blood-cells may be normal (physiological) for the individual cell. On the other hand, an exactly parallel series of possibilities obtains, although in each case the change is characteristic of pathological ceUs. We have, therefore, to discuss, in any cell, whether the senile change is physiological or pathological, or whether (here) the differentiation is a reverse process— an exhibition of a "reversible reaction." Such possibilities are better illustrated by means of a diagram {Fig. 6). If the length of the ordinate is representative of differentiation c^ Ageing Time, Fig. 6. — Diagram representing ontogeny and phylogeny in a cell series. ^changes in spacial relation), while the abscissa represents time, we can plot out a curve for the normal progression of cell substance (black line) and nucleus (dotted line). This curve, representing as it does the resultant between ontogeny and phylogeny, should be a straight line for cell-body as for nucleus, and the two lines should be parallel, or superimposed. A pathological change of any kind is at once indicated by a deviation from the straight course, and the two curves may be either parallel or not parallel. In each case we have a different pathological change. Let y represent differentia- tion of cell substance, and z that of nucleus, while t represents ontogeny, then y = t tan a + b* = z * 6 = a constant. The Primordial Cell 17 in physiology, while the pathological changes in the development of the primordial cell are represented by y = r sin (qt + e*), etc. A downward direction of the curve is representative of anaplasia. By this method of graphic representation it is evident that any given line of development presents every conceivable intermediate stage between the birth of a series of cells and the death of the last member of the race. A similar series of stages is met with in the study of any individual cell during its own life history. As a matter of fact, some portions of the curve represent changes in an individual cell while the remaining portions represent its progeny. In other words, following up the line, it represents first the new- bom primordial cell, then the same cell during an apparent latent period (as regards differentiation), then the dividing cell. The curve stUl goes on uninterruptedly, because the daughters are merely stages of progression of the whole famUy. Although the differentiation of these daughter cells has involved the loss of individuality of the parent, there is yet a continuous progress along the great highway, which is consummated in the appearance of the transportable blood-mature cell proper. Any of these intermediate stages can be seen and recognized in the tissue or in the film preparation. Many of the stages have been named irrespective of their relative positions in the line of develop- ment. Whatever be the objections to the nomenclature, they nevertheless form the only means of intercommunication of ideas on this complex subject. That such intermediate stages can occur is obvious from the above method of presentation, so that no more need be said to answer those who will not accept such minutiae as are expressed by the extensive nomenclature devised in recent years. The fact that basophile paraplasm is becoming converted into oxyplasm during the progress of an individual cell is fortunate, because the play of colours and structure enables the detection of subtle transition forms in preparations stained with suitable acid and basic dye combinations. ' e = a variable. 18 Biology of the Blood-cells A word of caution is necessary as regards the application of these general statements to clinical diagnosis : (i) Every transition form is not available for presentation, because some of the stages are passed over too quickly to avoid escaping recognition ; (2) Cer- tain stages in the Ufe history of different cell types may be very similar to each other, so that the personal factor may be required to differentiate them ; (3) Transition forms are Hkely to be met with which cannot be named, because nomenclature itself is incomplete, and because the characters are too undetermined or too transient to render definition of cell-form possible. u Signs of Ontogenetic Development. Signs of Old Age in A Cell. — As the cell becomes older, (i) The cell body becomes relatively larger ; (2) The nucleus becomes spherical and relatively smaller ; (3) The nucleus becomes indented and polymorphous.* A cell with a round single nucleus is younger than a cell with a polymorphous nucleus. The explanation of i is that the spongioplasm becomes more and more rarefied because .of intercalation of feebly-staining para- plasm in increasing amount.i^ The nuclear changes consist in a conversion of the weakly basophile parachromatin into oxychrom- atin (oxykaryoplastin). In proportion as these (always gradual) changes occur at different rates, so much the more are transition forms likely to appear. The three dicta quoted above constitute Heidenhain's three laws of cytology whose truth is agreed upon by most authorities. Signs of Phylogenetig Development. Signs of Differen- tiation OF A Cell. — The structure of the nucleus is the main sign- post indicating degree of differentiation. The evidence in favour of the view that the diagnosis of the nature of a cell must rest largely on the nuclear structure, is exactly the counterpart of the evidence which tells us that the granules are not specific. (See p. 222.) This statement brings up the controversy about the diagnosis of cell-forms by Ehrlich's method. The use of Ehrlich's triacid stain and the researches upon cell granules in the circulating cells have been the basis of all modem research upon blood-cells. • This law does not hold good in cells whose nucleus has a wheel structure. Erythro- blast nuclei undergo pycnosis with age.^'' The Primordial Cell l& The defective reaction of the triacid stain on nucleus is the- reason why many of the lymphoid cell forms have been lumped together, even though they have no real connection. The effective- action of the named dye on the cell-plasm has therefore led to the- attachment of undue importance to the cell-body as opposed to the nucleus. Schridde's phrase, that the nucleus is the heraldic sign of the cell, has brought out the alternative to Ehrlich's mode of classification very clearly, and is the basis of the classification of cells adopted in this book. We owe the full development of this side of the subject to Pappenheim. It will be found helpful to compare the successive stages of differentiation of the primordial cell with the various steps passed through by the nucleus of any cell during mitotic division. Just as the nuclear network is extremely dense during the resting period, so the linin is tightly arranged in the- lymphoidocyte (compare diagrammatic representation of Fig. 5) . When karyo- kinesis begins, the linin loosens out until a spirem with distinct convoluted threads becomes visible ; similarly, the chromatin is arranged into clumps during the leucoblast stage (granulocyte line, see Chapter V). As the spirem threads become thicker and shorter, an appearance is produced comparable with that seen in the myelocyte nucleus. The final cleavage of the chromo- somes, the spindle-formation, and the separation of the former into two groups which move to the ends of the cell, occur rapidly, and terminate with the production of two daughter cells — ^just as the myelocyte rapidly forms two daughter myelocytes. The analogy ceases at this stage, because there is- no counterpart in phylogenesis of any of the blood-cells with the reappearance of the close-meshed nuclear network of the resting cell. The description of all the nuclear changes and other details of phylogenetic development which the primordial cell may present during the course of its differentiation along the various lines, is given in each successive .'«*^, chapter, and need not be referred to at this j^»*' ^'\ stage. There is, however, one form of change S-^.*'**^^ deserving of notice, namely mast-cell trans- •-«^— formation (Fig. 7). Like any other cell, the ^Iywho^dootie' lymphoidocyte may develop mast-cell granules (Diagiammatic;. when suitable conditions arise. The signifi- cance of these, and the mechanism of their production, are fully dealt with in Chapter VI. 20 Biology of the Blood-cells A change into plasma cells is met with in some of the peri- vascular lymphoidocytes, and may be here mentioned for the sake of completeness. Duration of life.— The primordial cell usually passes its whole life within the confines of the haematopoietic tissues. In a very small proportion of human beings* it makes its way into the blood- stream, and gives rise to the clinical picture of (generally acute) l5anphaemia. It is only in this position that its duration of life could be ascertained. It is observed to multiply even while circulating, and so give rise to more daughter cells than the simul- taneous pathological phenomena in the bone-marrow supply. 5. Differential Diagnosis of the Primordial Cell or Lymph- oidocyte. — Inasmuch as the lymphoidocyte is a "lymphoid" cell, its detection will depend on similar rules to those applied to the diagnosis of either lymphocytes or monocytes (which see). It will suffice at this stage to point out that the interphyletically connected cells are very similar in morphology, and that careful observation of Giemsa preparations with a high ocular and oil- immersion lens are necessary for exact study. The cells which come imder consideration at this point are : — Variants of the mother cell : — The microlymphoidocyte and its senile form The senile lymphoidocyte Dwarf lymphoidocytes The lymphoblastic macrolymphocyte (see table opposite) The leucocytoid macrolymphocytes of lymphasmic blood The myelaemic microlymphoidocytes. Atypical mother cells : — The leucosarcoma cell of Sternberg The Rieder cell. The leucoblast and its leucocytoid form. Lymphoid hsemoblast (see p. 60). The lympha;mic microlymphocytes (see p. 132). The leucocytoid lymphocytes of normal blood {see p. 135). * It will be remembered that the primordial cell normally enters the blood-stream in many of the cold-blooded animals. The Primordial Cell 21 Myeloic Mother Cell. Lymphatic Mother Cell. (Myeloic) lymphoidocyte series ; Lymphoblastic macrolymphocyte lymphoidocytar myelolymphocytes series Spongioplasm . . Dark, markedly reticular. Soft, delicate, most shaggy contour abundant at peri- phery; clean-cut edge Paraplsism Feebly ox5rphile, especially in Chromophobic or dif- the astrosphere region fusely achromatic Azur gran. Fine, numerous, smaller, clear- Few, larger, clear-cut. cut, dusky red bright red, more or less round Nuclear shape . . more or less round ; may be paxanuclear dimple More or less round Chromatin Lepto-chromatic . . Pachychromatic, coarse trabecular network Parachromatin Clean cut ; distinctly baso- Cloudy, flaky, feebly phile oxyphile Astrosphere Present . . Absent Perinuclear zone Absent . . Present Nucleoli Single (oUgonucleolar) Ditto Clearly defined Ill-defined Feebly basoplule . . SHghtly oxyphile Lymphoidocyte Half-way Leucoblast CeU body Scanty . . Scanty More abundant, but varies Spongioplasm . . Basophile Basophile, Reticulated ; bsisophile or contour commenc- grey red (commencing oxy- ing greyish- plasma), but darker at red periphery ; amphophile contour Circumnuclear o Commencing + zone Azur gran. Occasional Occasional Often myeloic Nucleus Very fine Half fine.. Coarse structure net-work. Half coarse Relatively smaller relatively large Chromatin — — • Not yet completely marked off Parachromatin Basophile — — Nucleolus 2-4 One left . . o Senile form Rieder . . — Leucocytoid leucoblast. 22 Biology of the Blood-cells Fit;. S. I^EUCOBLAST f Diagrammatic), ' these cells and is Thf RiEDER Cell has the following characters :— Size— va.n3.hle. Shape— rounded. The cell-body is some- times relatively large, sometimes narrow; it is rather strongly basophUe, and exhibits a well-marked spongio- plastic structure whose meshes are small. Vacuoles may be present. The perinuclear halo is frequently distinct. Nucleus shows several indentations (lob- ate) ; occasionally only bi-lobed, but the division is sharp and clear-cut. Its structure is definitely leptochromatic (lymphoidocytar). A nucleolus is present. Mitosis. — Division is frequently seen in amitotic. This type of ceU varies in details accord- ing to the form from which it is derived, as other cells than lymphoidocytes may take on a Rieder form under pathological stimuli. This ceU is also called a Rieder leucosar- coma cell, and is really identical with the Sternberg leucosarcoma cell. It is common in leucosarcomatosis, chlorosarcomatosis, and in simple hyperplastic leukaemia. It is, however, not truly neoplastic, and is not exclusively met with in leukaemia and pseudoleuksemia (Zojai*). The Leucosarcoma Cell is an atypical lymphocyte, which has arisen from a prematurely senile change of the primordial cell. It is stated that such cells develop in the lymph nodes, in the stromatic, and not necessarily in the lymphadenoid tissue by changes of ana- plastic nature in the indifferent perivascular or mesenchymal cells. Such an interpretation is contradictory to the first statement that Fig. tRiEDER Cell (Diagrammatic.)* Fig. lo. — I,EUCOSAECOMA CEI.L.* (a) Resting; (6) In a condition of amitosis. In (6) the shading indicates theposition of an astro- sphere (left white). Compare the nuclear markings with those in Fig. 5. * The drawings are purposely diagrammatic in order to demonstrate how the main nuclear and cytoplasmic characters can be represented by a pen for the purpose of recording " bedside " microscopic findings. Compare Fig. 8 with Plate I, 3. The Primordial Cell 23 it is an abnormal senility of the parent cell. Since the appearance of such leucosarcoma cells is generally associated with the formation of tumour-like masses, it might be said to be a sarcoid metaplasia of the l5anphatic or myeloid tissues.is In other words, such cells are either lymphatic or myeloic in nature. This cell form is met with in : (i) Acute and chronic lymphatic leukeemia ; (2) Aleuksemic (sarcoid) lymphadenomatoses ; {3) Chronic and acute myeloses ; (4) Atypical (because leucosarcoma cells are preponderant) large-celled hyperplastic lymphatic or mye- loic leukaemias. It is either a normal senile form of the lymph- adenoid macrolymphocyte (2) or of the myelsemic lymphoidocyte (3), or an atypical cell identical with the Rieder cell. On the other hand it must not be confused with the ordinary lymphocyte of normal blood, with the lymphoblastic macrolymphocytes, nor with the large mononuclear cell of normal blood. The characters of the cell are identical with those named for the Rieder cell ; if there be any difference at all it lies in the functional abUity to pro- liferate indefinitely. The senUe and leucocytoid forms referred to in the above list differ from the type cell only in relative preponderance of the cell- body over the nucleus. 6. The Death of the Primordial Cell. — While there are no data which can serve to fix the duration of the life of a l3anphoid- ocyte, we find examples in the leukzemias which go to show that certain deleterious changes niay occur, leading to the appearance in the blood of degeneration and irritation forms of the mother cell. There is no reason why one cell should present other varieties of degeneration-pictures than another, so that we should expect to find, and therefore seek for, all such phenomena as are described later under the heading " Fate of the Myelocyte " {f. 207), " Death of the Polynuclear Leucocyte " (p. 228). The following changes have been observed by the writer : — Changes in the Nucleus. — Breaking up of the chromatin with vacuolation of the inter-chromatin substance, so as to lead to the appearance of radial floral figures, with the central or slightly excentric nucleolus left intact ; the nuclear membrane becomes more distinct, the cell-body pale [Plate I, Nos. 7-10). 24 Biology of the Blood-cells Changes in the Cell-body. — The principal changes here consist in the formation of vacuoles of small size, lying in single file round a portion of the circumference of the nucleus. They may be of the nature of fat drops. The formation of vacuoles has been described, in which the solitary azure granules of various forms and sizes occur. The granule or comma-shaped body is frequently excentric, and seems to be peculiar to the primordial cell (myeloblast) as it appears within the blood-stream in cases of acute leukaemia. Such bodies, while simulating protozoa, are not to be regarded as such at present, but rather as secreted products.i'si'? is i^ Plasmolysis may occur — the separation of small buds of cell- body2o (^Plate I, No. 7), which may presumably become ultimately cut off from the cell. These have been thought to appear in the blood-stream as platelets. Another possible interpretation is that they are not degenerative, but evidence of amoeboid movement. Undue friability of the Cell substance is a characteristic mani- festation of sub flnem vitce. Cytolytic forms like the Klein-Gumprecht shadows are also met with ; the nucleoli are stiU visible, but otherwise no details of structure are discernible. The irritation forms are chiefly characterized by extreme basophilia of the cell-body, increasing towards the peripheral portions. Small vacuoles also occur here and there in the bulky cell-body towards the nucleus, as if the paraplasm had been with- drawn from the periphery to appear in correspondingly conspicuous amount towards the nucleus. The process is then one of patho- logical sclerosis of the cytoplasm and atrophy of the functionating paraplasm. 2 2 Azur granules are never present. The nuclear structure differs from that of the lymphoidocyte in being distinct, well-defined, and tending to radial marking. The Primordial Cell 25 II.— THE PRIMORDIAL CELL (continued). Evidence pointing to the existence of a mother-cell for the adult blood-cells — The arguments in favour of (a) dualism, (6) unitarianism in haematology — ^Werzberg's and EUermann's experiments. The question whether there are different parents for the different forms of cell, or whether one primitive cell will give rise to various forms, is best answered by a consideration of the process of cell- proliferation observed in the testis, by a study of the blood of the lower animals, and by a study of the process of blood-cell formation observed in the embryo. I. Cell-proliferation in the Testis. — It will be remembered that the seminiferous tubules of the testis are lined by several layers of cells whose appearance varies according to the stage of development of the spermatozoa. It is not till puberty that mor- phological differences appear in the cellular strata, the components of the tubule-wall lying apparently inactive dur- ing all the preceding years. From puberty onwards, the lining cells of the tubules show differentiation into three layers, as shown in the accompanying Fig. ii : (i) An outer layer, nearest the so-called basement membrane,* is comprised of cuboidal cells which vary slightly in size, the largest being called spermatogonia ; (2) A middle Fis. II. — Spermatogenesis. (a) Sertoli Cell; (6) Spennatogonia ; (c) Spermatid; {d) Basement Membrane; (e) Dividing Spermatocytes. {Founded on Sobotta's figure, Quain, Vol. II., Ft. i, 1912.) • The usual definition of a basement membrane leaves a very unsatisfactory impression as to its purpose and significance. It will be borne in mind that in the coelenterates, for instance (sea-anemone, corals, medusae), the basement membrane constitutes a syncytium — a film of living substance of viscid consistence — from which the epithelial cells take their origin. In other words, this structure is a layer of undifferentiated cytoplasm giving rise to epithelial cells on the " air " or lumen side only — that away from the connective tissues. The familiar duct cells and secretory cells of the various glands are such epithelial cells. If 26 Biology of the Blood-cells layer of large spherical cells — the spermatocytes : in active tubules these frequently show different stages of mitosis ; (3) A thick inner layer of small round cells with resting nuclei — the spermatids; these are the immediate predecessors of the spermatozoa. A very remarkable series of phenomena comes to notice when the development of the spermatid into the spermatozoon takes place. The spermatid contains only half the number of chromo- somes present in the parent spermatocyte (homotypical mitosis), and the chromatin now becomes collected towards the head of the future spermatozoon. Adjacent spermatozoa collect together into bundles, the heads become directed towards the basement mem- brane, and are found to lie embedded within the columnar cells of the seminiferous tubule known as Sertoli cells {Fig. 11). It is the Sertoli cell that appears to play an essential part in the moulding of the spermatid into the future spermatozoon, since the cytoplasm of the one is found to blend with that of the other. The essential point of interest in these phenomena lies in the fact that the cells nearest to the basement membrane of the immature tubule constitute the primordial cells for the sperniatozoa, and become modified (by intramolecular change) to form spermatogonia only after a certain number of years of life. Previous to the puberty period their life history appears to be made up of nothing more than a maintenance of nutritional equilibrium. After the establish- ment of this epoch, an excess of energy becomes manifest in these cells (varying perhaps from week to week, but always present), resulting in the conversion of a certain number into spermatogonia, which, dividing into two, lose their identity, because each half is pushed on to the next layer by the new cells formed behind. The latter are arising anew by differentiation from the indifferent syn- cytial layer next to, and probably part of, the basement membrane. Blood-cell-formation is similar in some ways to the early stages of spermatogenesis. The adventitial cells of the bone-marrow the basement membrane gives rise to epithelial cells on both sides, but especially on that side which is directed towards the connective tissue, we should have the appearances seen in epithelial carcinoma. The basement membrane of the capillaries is also a material of the profoundest significance. Here, too, it may form a continuous living thing permeating the whole body, not always complete, but readily closing up defects by means of its semi-solid or viscid nature. The living material is rapidly destroyed after death, which accounts for its imperfect preservation in paraffin-cut material. The Primordial Cell 27 capillaries may be compared with the S3mcytial layer of the testi- cular tubule ; the larger indifferent cells immediately adjacent to the basement membrane correspond to cells which are spoken of in heematology as lymphoidocytes, while the smaller indifferent cells would be comparable with blood-cells further back in the line of development — conveniently distinguished as primordial cells, although there may be so little morphological difference between them, that we have believed it justifiable to describe them as synonymous in the preceding section. The lymphoidocyte is therefore to a certain extent analogous to the spermatogonium, while the primordial or mother cell is better compared, either with the (unnamed)* indifferent cell of the testis wall, or with the S5Ticytium enclosing the whole. Under the last-named analogy, the primordial blood-cell would really be identical with the adven- titial connective-tissue cell. Now it is evident that the pre-spermatogonium of the adult cannot be the same individual that was present in the embryo. This may be regarded as an axiom, and it creates no difficulty, because cell-forms are well known to continue reproducing them- selves for many generations without apparently altering their properties, just as the passions of man have been preserved unaltered through thousands of years. In haematology, however, there has been very much futile discussion as to whether a parent cell-form present in the embryo can persist throughout life or not. From the foregoing remarks it will be seen that there is no reason why a ceU- form should not do so, provided we do not imagine that the personal identity of the ceU remains. The functional, but not the corporeal identity of the primordial blood-cell, as of the pre-spermatogonic cell, persists from birth to death. There are two striking differences between ha;mo- and spermo- genesis. In the first place, the spermatogonia always produce one kind of product only, while the hsemogonia must be capable (on the unitarian view) of making at least two types of cells whose functional differences are very marked, although their morpho- logical properties are fairly similar. The only analogy between the * Say pre-spermatogonium. 28 Biology of the Blood-cells two, from the pathological side, would lie in the fact that just as the spermatogonia sometimes develop the power of unlimited non- differentiating proliferation, and produce a malignant tumour (the spermacytoma), so the hsemogonia sometimes develop powers of unUmited non-differentiating proliferation, and give rise either to the disease called leuktemia, or to the tumours variously named myeloma, chloroma, myeloblastoma, lymphoblastoma. In the second place, the spermatozoon is not the unadulterated product of division of the spermatocyte. The Sertoli cell has much to say in the matter, and we seek in vain for similarly functioning cells in the bone-marrow or lymphoid follicle. 2. The evidence afforded by comparative anatomy is in favour of the existence of a primordial blood-cell, because a lymphoid cell is preponderant in the blood of fishes, amphibia, and many birds. Indeed, in some fishes it is the only type of cell (Pappenheim). Limulus,* too has only one kind of blood-cell, which is non- amoebic, and has its granules at the periphery. 2 4 The caterpillar apparently has only one kind of cell, which is of mother-cell type .25 A similar cell is the exclusive cell in the bone-marrow of marsupials. It is the normal inhabitant of the circulating blood in lower animals. In spite of these accepted facts, Sternberg^" does not consider it safe to generalize from lower animals to man, and to assume that there is therefore one common ancestor to all blood-cells in human blood. 3. Embryology shows us that this cell is the sole occupant of foetal marrow and lymph-nodes, and is prevalent in the blood till the sixth month ;2 7 that it is the first cell to appear in the bone- marrow, thymus, and lymph-node parenchyma. Naegeli, however, disputes that lymphocytes appear before leucocytes,t28 and Engel and Gruneberg27 state that the red cells appear before the white cells, and do not even come from the vessel walls, but from the mesenchymal cells lying centrally within the solid primitive cell-strands. The arguments against the idea of a primordial cell are : (i) That fully differentiated cells occur elsewhere. Without any recognizable primordial cell being conditional. (2) The so-called * The kinR crab. f Browning made this statement."'' The Primordial Cell 29 mother-cell is a pathological cell entirely. [This is met by com- parative haematology, and is also disproved by Zoja.i^] (3) The arguments in favour of dualism, to be detailed presently. Granted that there is a primordial cell for the blood-cell series, it is of importance to know whether that cell gives rise to both red and white cells or not. It is usually considered that the erythrocyte is derived from a different parent from the so-called white cells, and the discussion about the relation between the parent and daughter- cells has centered in the question as to the common origin or not of the neutrophile leucocyte, the lymphocyte, and the large mono- nuclear cells. Those who consider that all cells come from one, are called unitarians in haematology ; while those who consider that the lymphocyte and the granular leucocyte come from different parents, are called dualists. The latter believe that there are two orders ot cells, the lymphoblast and the myeloblast, which are not inter- changeable at any time, and consider it as settled that the red cell comes from a totally different parent. The literature on the subject is very extensive, but need hardly be gone into at length, because neither view is entirely satisfactory. The supposed contrasts between the lympho- and myeloblast, which form the mainstay of the dualist argument, are presented below in some detail, a tabular form being convenient for the purpose.* The dualists deny that the primordial cell persists as such throughout life, but Maximow, Dantschakoff, and Neumann consider that it does. 2" 'i ^" It is supposed to renew itself from the fixed cells of the mesenchymal tissue. As we shall see later, this process can be observed in almost any surgical pathological tissue. A third view, that the parent or primordial cell may differen- tiate along as many different lines as there are main orders of cells, * In a sense, the dualist is also unitarian, because he presupposes that one given cell does give rise to lymphoblasts on the one hand, and to myeloblasts on the other, The difference between the two theories lies in the dualist believing that the primitive cell is only to be found in the embryo. The unitarian, on his side, is dualist in a certain sense, inasmuch as he admits two separate lines of development for the lymphocyte and leucocyte series, after a certain stage has been reached. The strict imitarian holds that there can be no interchange between them after this stage. The transitional or modified monophyletist view, on the other hand, admits all kinds of intercormections between the lymphatic and myeloic series. In presenting the arguments pro and con, we make no distinction between the two variants of unitarianism — ^because the subject is complicated enough without introducing the further subtleties of reasoning in the last-named direction. As stated below, the full argument for the modified unitarianism is the theme of this volume. 30 Biology of the Blood-cells and that interchanges can and do occur between any one daughter cell and another, is more satisfactory in many ways. The lympho- cyte, for instance, may revert and branch out on the other line — that of the neutrophile leucocyte — by means of a cytometaplastic process, during which the original cell acquires characters which lead to its being labelled a micromyeloblast. This intermediate view is specially advocated by Pappenheim, and deserves wide recognition. Many of the arguments in its favour are covered by those given below in favour of unitarianism. The additional evidence is afforded during the progress of this book, inasmuch as the subject matter is arranged with this view-point foremost in the mind. The ease with which certain obscure chapters in " blood-disease " pathology can be rendered clear by this " tran- sitional conditional monophyletism " is finally brought out in the concluding chapter. At the present stage, therefore, we present briefly the evidence in favour of each of the two first-named prominent modern schools of thought. Expressed more graphically, these views are : — Dualism : — / Lymph vessel endothelium -* Lymphoblast or macrolym- Fixed embryonic I phocyte -* lymphocyte connective-tissuel lympherythroblast -> erjd;hro- ^^^^ ^Blood-vessel endothelium blast-> erythrocyte myeloblast^ myelocyte-* leuco- cyte Unitarianism : — [ lympherythroblast -^ erythroblast ->- red cell Lymphocyte -^ macrolymphocvteJ , , , \ myeloblast^monocyte-*- myelocyte [ -^leucocyte Pappenheim : — / red-cell series Indifferent blood-cell->lymphoidocyte J leucocyte series lymphoc5rte series (monocyte series and potential interconnections. As will be discussed later, it may be nothing more than a question of environment whether these interconnections take place or not. The Arguments in favour of Dualism.* — Leaving out of count the problem of erythrogenesis (the development of the red cell). The chief dualists are : Blumenthal, Ehrlich, Helly, Lehndorff, Morawitz, Naegeli. Pincus, Schridde, Sternberg, K. Ziegler. The Primordial Cell 31 we find that the white cells belong to two main classes, those which appear non-granular with Ehrlich's triple stain, and those which are granular. The former are classed as lymphatic and the latter as myeloic cells. If it can be shown that there is absolute antithesis between these two groups of cells, then the assumption is that they do not come from a common ancestor. The supposed differential characters between the myeloid and lymphatic cells are conveniently set forth as follows : — Myeloid Lymphatic (a). Relation to Only to blood-vessels, viz., in Only to lymphatics vascular chan- embryonic liver the mye- nels loid tissue is perivascular. Pathological myeloid tissue in the adult arising in lym- phatic tissue is stUl peri- vascular (6) . Structure of Disorderly (e.g., no follicles) ; Orderly (foliicles) the tissue cells scattered irregularly among other elements (c). Association Frequent.. Never with red - cell formation (d). Chemical fea- Contain autolytic and peptic tures ferments* Do not Guaiac test + t Guaiac test o (e) . Biological Amoeboid movement Only slight charactersX Marked phagocytosis Chemotaxis takes place even No in lymphatic leukaemia . . No {/). Embryology (i). Alone present in liver ; Alone present in thy- pulp of spleen comes first mus, M-bodies of spleen come last. (ii) Usually associated with Never erythropoiesis in embryo . . (iii) Appears first . . Appears last (Naegeli)^*- * The proof of this is that in croupous pneumonia (polynuclear exudate) the tissue liquefies ; in caseous pneumonia (lymphocytes) the tissue undergoes necrosis. t Proof— test absent (no oxydase) in lymphatic leukemia or in a chronic lymphatic exudate. Bone marrow gives the test, but lymph glands, thymus, etc., always fail to- give it. The objection to all this lies in the fact that the test is being applied to mature cells in each case, whereas the primordial cell is immature. X Such functional differences are emphasized by Bergel.^'' 32 Biology of the Blood-cells LVMPHOBLAST Myeloblast (g). Morphological features — Contour of cell 111 defined Well marked Cell body (a) Relatively more abundant . . Relatively less abun- dant (b) Less basophile More basophile (bright red with methyl- green pyronin) (0) No reticular structure Finely reticular struc- ture Granulation : — (i) Altmann + o (Schridde) Schridde + (Butterfield, Heinecke, Meyer, St. Klein) ;=' occasional : Wallgren, Maximow. (ii) Azur . . + + (Grawitz, St. Klein) (iii) Specific + Oxydase : — Occasional (St. Klein) + (but only in the myeloblast of myelo- blast leukaemia)32 Nucleus : — Membrane Dense Dehcate Chromatin net- Dense and coarse . . Dehcate and fine * work Mitosis '^Tl■t />lia^^lii o • Constant Occasional i.N UClCUiUb . Number 1-2 2-4 With methyl- green pyro- nin . . Distinct, deep red . . Indistinct, pale red <*->y Fig. 12. — Diagram to show the contrast between (a) lymphoblast and (6) myeloblast, according to the dualist doctrine. * Not very clearly demonstrated in Schridde's plate.'= The Primordial Cell 3? (h). Pathological evidence : — Infectious fevers cause hyperfunction of myeloid tissue first ; of lymphatic system later. Pernicious anaemia affects cytogenesis in the bone marrow but not in the lymphatic tissues. Tuberculosis acts in the reverse way. True lymphatic tissue never turns myeloid, but is replaced by it. In myeloid metaplasia the follicles never show active change ; they are merely compressed, and atrophy from the overgrowth of the pulp. In other words, the myeloid and lymphatic tissues are antagonistic. Lymphatic tisssue does not turn myeloid, but is displaced by the latter. The leukaemias are distinct (but see below) . {i). The dualists state that all transitions can be seen betv/een the myeloblasts and the neiitrophiles, while there are no transitions between myeloblasts and lymphocytes. (/). Effect of short-circuiting the thoracic duct : there is lymphopenia. But this is due to the operation, thrombosis, and consequent interference with the lymph-flow occurring in the area. The subsequent lymphocytosis is due to the lymphocytes getting in via the lymph nodes direct. (k). The organs used to demonstrate unitarianism were them- selves pathological in character. (/). Comparative cytology is misleading ; it is not logical to generalize from animals to man (Sternberg) .26 The Arguments in favour of Unitarianism* : — (a). That there is no real distinction between the myeloblast and the lymphoblast ; even the dualists admit that myeloblasts and lymphoblasts never occur together.! (b). That in selaciaj there is a protometrocyte which gives rise to cells with amblychromatic nuclei at one time and trachy- chromatic nuclei at another, and still is devoid of lipoid material in its cell body.^e (c). Maximow's observation that in amphibia and selacia there * The chief unitarians are — (i) Extreme : Arnold, Grawitz (late), Sohleip. (j) Moderate : Dominici, Lowit, Maxiraow, Neumann, Tiirk, Weidenreich. (3) Trunsitional ■ Pappenheim, Hirschfeld, Eric Meyer. t This is replied to by saying that morphological resemblances are no proof of identity of nature (Sternberg).*" } E.g., the dogfish. 3 34 Biology of the Blood-cells are no sharply demarcated lymphoid organs in which, on the one hand, lymphocytes alone are produced, and on the other, granulo- cytes alone. Wherever there is l5nnphocytic infiltration, there one may find granulocytes occasionally formed. In other words, the Mood-lymphocyte is capable of further development after leaving the blood-vessel : to wit, into a polyblast, and even into a myeloid ■cell under certain circumstances (Lindberg).3 7 In the lower vertebrates,* at least, there is a polymorphous wandering indifferent mesenchymal cell with multiple potentialities. (See also Plate I, i.). Hal Downey figures preparations from the amphibian amblystoma (the mature form of axolotl), which point in the same direction.ss Moreover, working on the chick, Wera Dantschakoff^s found that the intravascular erythroblasts are morphologically the same as the extravascular granuloblasts ; further, that the intravascular " blasts " eventually make lymphocytes. Certain observations by Dantschakoff^" on the bone-marrow of fowls during hunger are of considerable importance in this connection. The changes in the marrow consist of an increase of the feebly basophile poly- nuclear leucoC3rtes, vacuolation of the cell-body, and general amblychroma- tism of the myelocytes. The lymphoid areas become rich in plasma cells, and small lymphocytes become very much more numerous, while the edges ■of the areas demonstrate metaplastic conversion of lymphocytes into gran"ular leucocytes, pari passu with the diminution in number of the myelocytes. The fact that the central cells of these lymphoid areas are morphologically identical with the myeloblastic cells of ordinary bone-marrow shows that the same kind of cell can turn into a lymphoid cell at one time, and a polynuclear at another. {d). Granulocytes are absent in many animals, but large monocytes (Chapter IV.) and small lymphocytes are present in every animal. Moreover, while the morphology of the granular leucocyte is inconstant in different animals, that of the lymphatic •cell remains uniform throughout the animal series.is {e). The white cells and red cells are developed together in the lymphoid tissue of the kidney of the fish polyodon. Such an animal does not possess myeloid (bone-marrow) tissue at all >(Drzewina,4o Hal Downey^i). * Also, even as low down the invertebrate scale as the sponges. The Primordial Cell 35 (/). The observation has never been made that the lymphoid cells in an (acute leuktemic) actively proliferating lymphoid tissue (at the expense of the myeloid) are the only specific cells to exhibit mitotic figures. This would need to be definitely established before dualism could maintain its ground.42 (g). Further, in acute leukaemias we find the following peculiarities : (i) The condition is never purely lymphatic or purely myeloic ;* (2) The gland may not be enlarged, so that bone- marrow can make lymphoid cells ; (3) Schultze found that acute lymphoblastic leukaemias are really myeloblastic, because the cells in the spleen and lymph nodes gave an oxydase reaction and were myeloblasts, f {h). Ellermann's43 success in transplanting leukaemia of hens by means of a cell-free material, indicates that that disease is infective in nature. J This being so, the leukaemic process is granulo- matous, and not neoplastic. The dualist view makes it neoplastic, inasmuch as the original haematopoietic cells are considered to be replaced or substituted by a new tissue altogether.20 (i). Werzberg's experiments with myelotoxins and spleno- toxins.44 The following four experiments were performed : (i) Intraperitoneal injection into a rabbit of rabbit-bone-marrow-immune guinea-pig serum •(the bone-marrow was extracted and injected intraperitoneally) ; (2) Same as preceding, but using smaller dose ; (3) Injected rabbit-spleen-immuno guinea-pig serum ; (4) One of the animals in experiment 2 died of pneu- monia. Results : the myelotoxic serum in large dose caused hypertrophy of the spleen folUcles with myeloid metaplasia of the pulp ; the lymph nodes showed hypertrophy of the germ centres and follicles, and occasionally myeloid metaplasia of the pulp ; the bone-marrow was fatty and the liver normal. In smaller dose, the myeloid metaplastic changes failed to appear in either spleen or glands, but the other changes were as before. When associated with pneumonia, the toxin caused atrophy of the follicles of the spleen, myeloid metaplasia of the pulp, disappearance of the follicles of the lymph nodes, with appearance of large lymphocjrtoid cells in the interfoUi- • Example : Fleischmann's case, Charitt-AnnaUn, 1909. t This is really the same thing as saying that the lymphoblast is identical with the myeloblast. Was myeloid metaplasia excluded ? A lymphoblastic or myeloblastic leu- ksemia may have identical features in every particular, save the presence of myeloid meta- plasia of the spleen in the latter (Pappenheim, Ziegler, Voswinckel, and Danzelt). % Some authorities do not consider the leukajmia of fowls an identical disease with the liuman leukaemia. 36 Biology of the Blood-cells cular tissue, and myeloid metaplasia in the liver. The splenotoxic serum caused myeloid metaplasia of the spleen pulp and no change in the pulp of the glands, but there was hypertrophy of the follicles throughout. The deduction is that the same toxin that causes myeloid metaplasia can cause hypertrophy of the lymph follicles. The weaker toxin excited merely follicular hyperplasia. The pneumotoxin causes atrophy of the follicular tissue. On the other hand, it will be seen that the lymphatic tissue never becomes myeloid ; the experiments confirm the view already expressed that the pulp tissue of the nodes and spleen are fundamentally identical : — / Myelocyte (myeloid metaplasia) Primordial cell of pulp tissue-*. Lymphocyte, which, proliferating, be- comes manifest as a misplaced lymph-follicle. * The difficulty that lymph follicles never undergo myeloid meta- plasia is explained readily enough when we come to regard the follicle cells as temporary and not primordial cells. This subject is very important, and is dealt with again later. The conclusion of the matter is that we assume the persistence of a primordial cell throughout life, and that its after-history takes the form of one or other of the five main lines of blood-cell develop- ment — the red cell, the lymphocyte, the monocyte, the neutrophile leucocyte, and the phlogocyte. We shall take up each of these in turn in the succeeding chapters. * That this is correct may be readily demonstrated in the lymph nodes of any autopsy. The question will be referred to again, as so many examples from the autopsies at the Montreal Royal Victoria Hospital have been met with. It will be seen that this finding in itself strongly supports Werzberg's view, especially considering that observations on man. are worth so much more than those on animals. The Primordial Cell 37 III.— THE PRIMORDIAL CELL (concluded). The Cytometaplasias of the Lymphoidocyte. The subject of cytometaplasia is best considered after the various blood-cell forms have been studied, but it is advisable to make some reference to it at this point in order to complete the conception of the primordial cell. It is not sufficient to describe its characters, its origin, its fate, and the physiological transforma- tion into the other blood-cells which it undergoes ; the fact that it is subject to pathological processes, under the burden of which it gives rise to granulomatous and neoplastic formations (to mention some of the most interesting of the changes), must be considered in order to complete the survey of the biology of this ceU-type. When discussing whether a primordial cell persists throughout life or not, reference was made to the process of spermatogenesis, and it was pointed out (p. 27) that the spermatogonium may retain its functional but not its corporeal identity during the succes- sive generations. The same phenomenon may occur in the case of the blood-cell parents. The primordial blood-cell or lymphoidocyte may give rise to two daughter cells. These are either both lymphatic or both myeloic* Even though the two daughter cells both belong to the same series, there still remains a necessity for assuming that one of the two retains the functional characters of the parent, the other alone being destined to differentiate. In the case of the seminiferous tubule, for instance, a certain number of the cells nearest the basement membrane always remain " primordial," (potential spermatogonia), no matter how often they have divided. The diagram on page 38 will make the argument clearer, the successive changes in the functional character being indicated by linking (Fig. 13). The black spots represent juvenile or temporary stages that become more differentiated during ontogenetic development. The linked forms are actually always * To judge by some of the mixed leukxmias, one of each variety is possible. 38 Biology of the Blood-cells in the same spot, so that the primordial cell is apparently- unchanging. Whether the second generation does or does not differentiate depends entirely on the presence or absence of suitable stimuli or transient influences from without. A cell which under- went myeloic differentiation yesterday, might undergo lymphatic change next week, and the latter might just as well " revert " the following week, undergoing anaplasia and then changing into myeloic cells once more. It is only in this way that one could explain the onset of an acute leukaemia with lightning-like rapidity. /\ •-® y \ #-e seen "' (p- 47). Fig. 2o.^PiGMEXT IN BoNE-isi ARROW, (a) masscs of pigment completely filling cells ; {b) fat cells ■ (c) red blood cells ; {lij formative cells. (Oe. 4, Zeiss Oil-immersion). Bone-Marrow as a Red-cell Factory 45 I.— THE BONE-MARROW AS A RED-CELL FACTORY. The red-cell forming group — ^The white-cell forming group — The megakaryocyte, its significance ; views as to its nature and function ; occurrence — ProUferation of cells in the bone-marrow — ^Metaplastic and allied changes in the bone marrow — ^Functions of the bone-marrow. ACTIVE or formative bone-maxrow occurs as a reddish material in the stemimi, bodies of the vertebrae, ribs, diploe of the skull, and the ends of the long bones. In bones other than these, the formative cells are for the most part masked by the fatty tissue. The latter is compensatory material, somewhat of the nature of packing, but is of importance to the parenchymal tissue by afford- ing the nutritive means by which metabolism with differentiation can take place. The bone-marrow, whose typical structure is shown in Fig. i, is made up of a vascular connective tissue occupying the interstices of a variably dense bony trabecular framework. The blood- vessels stand out conspicuously owing to vascular engorgement, and the size of the inter-trabecular spaces relative to the small roimd fat cells ^^dthin them is weU demonstrated. Seen with a higher magnification (Fig. 17), these round spaces become recog- nizable as adipose connective-tissue cells, and the relations between them and the surrounding closely packed discrete tissue-cells become more clearly visible. The latter vary in size — some of them, the so-called megakaryocytes, being strikingly large. Small capillaries are seen here and there as small pale bands among the marrow cells, but the c3^ological details of the latter require stiU higher magnification for their detection, even such gross points as variations in intensity of staining being visible with difficulty. Examined with the oil-immersion lens, however (Fig. 18), the formative cells themselves are seen to be of various types. They have been called " marrow leucocytes," and are divisible into a leucoc5d;e and a haemoglobin-holding series (Carnegie Dickson). A third group might be added, that of the indifferent or indeterminate cells, possessing var5dng or multiple potentiahties 46 Biology of the Blood-cells — sometimes erythropotent, lymphopotent under certain conditions, and sometimes leucopotent. In addition to these parench5mial cells there are the interstitial cells (giant cells, connective-tissue cells, and endothelioid cells). The Red-cell Forming Group. — These include the normoblasts, the megaloblasts, and their parent cells. It was the presence of such cells in large numbers in adult bone-marrow that led Neumanni to discover the source of red cells during extra-uterine life, the " -blast " undergoing mitosis, its progeny losing its nuclei, or budding off portions of the cell-body .2 In studjdng microscopic preparations of bone-marrow, it is found that the parent cells of both red and white cells are difficult to distinguish. In the case of the lymphoid erythroblast, the parent of the red cell, the nuclear matter is found to be character- istically arranged along the periphery of the nucleus, with central chromatic spots. The nucleus of the lymphoidocyte never shows this structure, but presents a diffuse ill-defined variation in density of chromatin. Giemsa preparations generally show the presence of a nucleolus in the lymphocyte series, whUe the later generations of the parent red cell certainly do not. When the nucleus of the red cell undergoes pycnosis, there may be a superficial resemblance to a neutrophile leucocyte whose granules have been lost from degenerative changes. As a rule, a slight greenish or bluish tint is noticeable in the normoblast cell-body from the presence of more or less haemoglobin. The megaloblast (see p. 61) may occa- sionally be mistaken for a lymphoid cell, but the structure of the nucleus is characteristic — radial arrangement of the lines of chromatin [Fig. 19). The White-cell Forming Group. — This is subdivided into {a) non-granular and (b) granular cells. The latter are characteristic and well known. Granules are always clearly shown in triacid preparations, but the characteristic nuclear structure — rather coarse, but ill-defined transverse shadowing — is best seen in the panoptic preparations. The granular cells of the marrow are, of course, myelocytes of one kind or another ; that is, they have an oval, reniform, or deeply indented nucleus, as opposed to the polymorphous form in the adult leucocyte. The nuclea,r structure Bone-Marrow as a Red-cell Factory 47 differentiates these cells from the large mononuclear and transi- tional cells of EhrUch. The presence of neutrophilic, eosinophilic, or basophilic granules affords a basis of classification. Many of these cells are actively amoeboid, and have phagocytic properties, so that red cells or pigment granules may be seen within them (Fig. 20). It is this fact, added to the chsinges due to pro- gress of development of the bone-marrow cells, synchronously with the phenomena of active mitosis, that explains the remarkable inconstancy of structure of this tissue, not only in the different diseases, but also from hour to hour and from day to day, dining the life of the individual. There is need for small wonder at the remarkable rapidity 3 of adaption to incoming morbid or physio- logical stimuli. We cannot fail to be impressed with the multi- pUcity of the changes in which one or other of a group of cells is concerned — regenerative, degenerative, reparative, aberrant. We may compare the ever-active and ever-responsive character of the blood-cell parents residing in the bone-marrow to the restlessness and excitement seen in a crowd of spectators who press forward beyond the barrier for the purpose of obtaining a better view of the object of their visit, but are forced back by the rigid rules adopted by the vigilators of the course for the maintenance of order. The pigmentophages vary greatly in size, and contain a feebly staining oval nucleus Is^ing in an abimdant non-granular cytoplasm. They are probably derived from the endothelial cells of the capillaries as well as from the branching reticular cells. The non-granular cells (Fig. 51) are crudely divisible into small, medium, and large mononuclear forms. They may be regarded as representing stages farther back in the line of develop- ment than the granular cells, the blood-mature l5rmphocyte, and the red cell respectively. The largest example of the former is the primordial cell already discussed, although its exact aspect in the tissue was not detailed. This is, then, the mother cell, the large l}nnphocyte of older authors, the l57mphoidocyte of Pappen- heim. Here, a small rim of basophUe cytopla.sm is noted, with a relatively large ovoid nucleus of variable basophilia, but character- istic structure and nucleolar content. There may be definite 48 Biology of the Blood-cells peripheral chromatic marking visible in the tissue-sections. It is convenient to call this cell simply " mother cell," which serves to indicate its place in development and avoids the selection of one of the twenty-three names with which various writers have presented the same innocent cell. Between this cell and the promyelocyte it is possible to interpose a leukoblast stage {see p. 203). Com- mencing acidophUia of the cell-body, still without definite neutro- philic granules, indicates that we have a promyelocyte before us — a cell further on in the line of ontogenetic development, but also included with the non-granular cells. The leukoblast often shows azure granulation, but is not classed as a granular cell because this variety of granulation is non-specific. Before passing on to consider in detail the red-cell forming series, it is important to refer more particularly to the stromatic elements. Of these, the giant cell is conspicuous. This is a large multinucleate cell met with in varying numbers in marrow tissue. There are two forms of giant cell : {a) The osteoclast, usxially met with in the vicinity of bone-trabeculse, when absorption processes are going on ; (6) A variably large cell, constantly seen in sections of the bone-marrow, but not seen in film preparations — the mega- karyocyte (myeloplax of Robin). All forms and sizes of this cell are met with, and even the nuclear characters are not stereotyped. Characters of the Megakaryocyte. [Plate VII, 23, 24, p. 250, and Figs. 39, 74). Size. — 30-45 fj. in the adult, smaller in embryos. Shape. — Round in the physiological state.* Cell-body. — Stains bright red with eosin, strongly red with methyl-green pyronin. It shows an outer hyaline zone, in which radial filamentous marking is visible (minute pores ?), and an inner granular zone, separated from the former by a pseudo- membrane.5 Sometimes it is deeply stainable, where the granules are numerous ; at others it is only faintly stainable (few granules). A network permeates the inner zone, and contains vacuoles, clefts, or vermiform spaces.^ The pseudopodia also show an outer hyaline margin and an inner granular zone.^ Granules. — (a) Staining by Altmann's method ; (6) Staining with Giemsa. The latter are much more abundant, and occur Bone-Marrow as a Red-cell Factory 49 unifonnly distributed through the granular layer, or in rows, or in dense patches like the tigroid patches of nerve ceUs.s The presence of these specific granules shows that the megakaryoc5rte has nothing to do with the lymphocjrtar or leucoc5d:ar series. The Altmann-Schridde granules are abundant even in the pseudopodia, which penetrate into the Imnen of the capiUary. Here they occur in clusters, marked off by a hyaline zone of protoplasm. Nucleus. — This is protean in form, always vesicular. Its outline is sometimes lobate, sometimes only indented, sometimes moniliform, sometimes basket-like, or annular, or horse-shoe-like. The chromatin network is abundant and the interchromatinic substance is abundant. In the hollow of the nucleus are a number of centrioles grouped together into a small cluster, or they are scattered about in the central zone of protoplasm. Mitosis. — Always indirect.^ Baes and Lustig described pluri- polar mitosis. C. E. Walker described division by amitosis.io Motility. — Amoeboid motiUty is present. It is therefore probably a phagocytic cell. Differential Diagnosis. — From other giant ceUs — see Chapter VII. Ancestor. — Saxer's primary wandering cell,^ or the stellate con- nective-tissue cells.4 * They are not the first cells to appear in the foetal marrow.4 Blumenthal and Duesberg* believe them to arise by fusion of lymphoid mononuclear cells, and by fusion of nuclei. Occurrence in Marrow. — The distribution is always irregular. The numbers vary according to the degree of redness of the tissue,* or according to the number of isolated nuclei and pigment-con- taining cells,'' but diminish with age.* They are more numerous towards the end of foetal life and during the winter sleep of bats.* They also occur in the spleen^ and lymph-nodes.^ The Significance of Megakaryocytes is not settled. Schridde states that they are amoeboid but non-phagocytic. They appear to have some connection with hsemogenesis, because they are munerous in foci of active blood-ceU formation, and have close relations to the blood-vessel walls, dangling their long pseudopodic * Versou does not agree.' 50 Biology of the Blood-cells arms into the blood-channel." They are scanty in cases of tubercu- losis, cancer, chronic nephritis, and aU bacterial infections. They were found to be very abundant in a case of aneurysm in which leakage had taken place for a considerable time.12 They are increased in pneumonia, septicaemia, and appendicitis. Degener- ative changes in such cells are worthy of note. Views as to Nature : — 1. That it is the result of proliferation of the endothelium of the vessels (KoUiker). 2. That it is produced by the fusion of several leucocytes (Sanfelicew). 3. That it is merely a giant leucocyte (Howell, v. Stricht, Kastanuchi, Heidenhaini^). 4. That it is derived from the reticular cells of the bone-marrow, being a phagocyte for red cells (Ebnerie). 5. That it is derived from the lymphoidocyte (Pappenheimi^).* Views as to Function : — 1. That it destroys leucocytes which are no longer capable of functioning (Foais). 2. That it is the parent of the polynuclear leucocyte, because peculiar structures are occasionally seen within it (Werigo and Jaguinowi«).t 3. That it is the parent of red cells (Lifschitz^o), because they are more abundant the more numerous the erythrocytes. J 4. That it is the source of the blood-platelets (Wright,2i Bunting,22 Ogata,2z* Sternberg's). The arguments in favour of this view are : (i) That projections from the cell-body into the lumen of the vessel can be actually seen ; (ii) That this form of cell only occurs in mammals, and the platelets are not found in the blood of any but mammals ; (iii) That the more numerous giant cells are in a tissue, the more abundant are the platelets in the blood (few in pernicious anaemia and lymphatic leukaemia, numerous in post-haemorrhagic anaemia and myeloid leukaemia). The refuta- tion of these arguments is to be foimd on f. 87. * The writer considers this view the most probable, for reasons given in Chapter VI I. t Denied by Schridde. % Denied by Tomassi. Bone-Marrow as a Red-cell Factory 51 5. That it forms a ferment which acts on the extruded nuclei of the red ceUs, reducing the nucleohistone to nuclein and histone. The latter is subsequently utilized to form haemoglobin in the on- coming red cells (Ciaccio^^). This view is far more in keeping with physiological cytology, and provides an analogy in the forma- tive organs to the Sertoli ceU of the testis. Where active cell- differentiation is going on, the specialized metabolism appears to demand the presence of specialized cells. Proliferation of Cells in the Bone-Marrow. — In mammals, the formative cells of the bone-marrow are apparently all extra- vascular, even the red cells making their way through (possibly) incomplete capillary walls. But in birds the walls of the capillary are complete, and the red cells are formed in dilated sinus-like portions of the blood-vascular system of the bone, the parent cells being close to the wall, while the fully-developed red cells are towards the centre of the lumen, and are washed off by the slowly circulating blood.25 In addition to this, certain of the marrow cells without the vessels are proliferating, in order to supply fresh er5rthroblasts along the peripheral portion of the vascular channel, and these parent cells make their way through the vascular wall in the same way as the finished red cell is supposed to emerge in the case of the mammal.26 It would be of interest to determine exactly how much cell- multiplication is required hourly in order to maintain the adult's blood at average cellular richness. The accepted mechanism of red-cell formation might then be found to be entirely inadequate. Assuming that there are about five litres of blood in the body, and that the average hfe of a red cell is ten days,67 we shall find that about 105 thousand million red cells have to be formed within the body every hour, both day and night. If it were possible to estimate approximately (say within 20 millions) the number of marrow cells in the body, it would be easy to see if mitosis would meet the case.* Multiphcation at bacterial rate is not admissible, because this would provide a steadily increasing output. The rate * Timofijwsky (Russky Wratsch, 1912, 24) made cell counts and found that a c.mm. of marrow tissue contains 0-674 million erjrthroblasts. 52 Biology of the Blood-cells of red-cell destruction is to be assumed to be the same (see also p. 73). We should have to assume a formation of red cells by meristem methods, whereby ten, fifteen, twenty or more young cells are formed with great rapidity from one parent. On the other hand, mitosis is not so remarkable a feature of these proliferating tissues.* Forma- tion of red cells by buds from other cells, though depicted by Maximow,27 is not accepted as even a potential and occasional method. Metaplastic and Allied Changes in the Bone-marrow. — These are conveniently considered in connection with the pol3aiuclear leucocyte (see p. 199). The aplastic changes, however, are referred to in Section IV. The Functiona of the Bone-marrow. — These may be enumerated in this place : 1. It is haemopoietic for red and white cells. 2. It is associated with blood-destruction and the phagocytosis of organisms. This property is increased in toxic diseases and the acute microbic infections. Agglutinins are made here, according to the observations of Azzurini. 3. It has to do with the formation, nutrition, and absorption of bone. Occasionally, the absorption of bone serves the purpose of providing more space for red-cell formation. 4. It has to do with general metabolism ; with this is associated the function loosely named " internal secretion." 5. It has to do with the preparation of fibrinogen. Miiller found that there is more fibrinogen in bone-marrow in experimental staphylococcic infection, and that when defibrinated rabbit blood is injected into the same animal, marked leucocytosis occurs, with myeloid metaplasia in the bone- marrow, spleen, and liver. If hirudin blood were used (containing fibrinogen, but not coagulable) it caused leucocytosis without myeloid change. Effect of Toxins. — Intravenous injections of saponin into rabbits (Isaak and Mochel^*^) produces cell-complexes of normo- and megaloblasts, and indifferent marrow cells ; necroses occur here and there ; in other cases there are regressive changes present. After long-continued treatment the bone-marrow disappears, the adipose cells being replaced by connective tissue, which becomes very dense, and small foci of blood-formative cells may appear so soon as the animal has developed an immunity against the sapotoxin. * It is usually stated that the mitotic phase is so readily passed through, that it might be missed in microscopic sections. This, however, has only a theoretical basis. The Erythroblastic Line of Development 53 II.— THE ERYTHROBLASTIC LINE OF DEVELOPMENT. General outline of the process — Charts showing the details of erythropoiesis (a) in the embryo, (6) after birth — Characters of the lymphoid erythroblast, and how it is formed from the primordial cell — The megaloblasts — The chemical characters of these ancestral cells — ^Their differential diagnosis — ^Views as to the nature of the megaloblast — The normoblast, its characters, its difierential diagnosis — Red-cell formation in the liver, spleen, and lymph-nodes — ^The birth of the red cell into the blood-stream — Theories of the process of denucleation. The lack of uniformity noticeable in the statements made about the mode of development of the red ceU is largely owing to the utilization of different material by different observers. It is not to be expected that the red cells of the chick, for instance, wiU be formed in the same way as those of the guinea-pig, and these in the same way as in man. Where it is possible to combine the different methods, it would be an advantage to present an account containing every variation, as a basis, because every contingency would be covered thereby. There is much objection to offering a description of the process of red-cell formation in words. It is therefore designed to show a series of genealogical tables, and allow them to speak for themselves. It is simpler to separate erythropoiesis into two stages than to endeavour to trace the continuity of development from the earliest embryonic life to the adult. The formation of the primitive blood cells in the embryonic yolk-sac is one process, that of the secondary blood-cells in the proper blood-forming organs is another. In the yolk-sac we find the following sequence.^s The meso- dermal cell of the yolk-sac becomes the mesenchyme cell, which functions as an angioblast.* This is a branching cell with granular body and small nucleus, very similar to an ordinary connective- tissue cell. As soon as a number of these cells, formed simul- taneously, come together, t they come to be called Pander's islands ; * The mesenchyme cell is also called a parablast (His).^' t Some authorities regard them as collected into syncytial masses, but Maximovv and Dantschakoff do not. 54 Biology of the Blood-cells and when adjoining islands have fused, we have before us the network of primitive blood-vessels called the area vasculosa. The angioblastic cell now multiplies and gives rise to three types of cell : (i) the perivascular cell, (ii) an endothelial cell, (iii) a hsemo- blast or mother cell of the erythrocyte. These form three layers, with the last-named innermost {Figs. 21, 22), and it will be evident that the endothelial cells wiU join into a membrane, separating off the haemoblasts within from the perivascular cells without. Fig. 21. — ^Transverse Section of Primitive Blood-vessel (after Maximow). (J) Mesenchyme cell; (2) Endothelial cell; (3) I,ymphoblast ; (4) Primitive erythroblast (5) Cavity of developing vessel. The haemoblast divides into the primitive erythroblast (lymphoid erythroblast of Pappenheim) {see p. 60), and the primitive lymphoblast, or non-haemoglobin-bearing cell. All these stages are extra-embryonic. At the same time, changes are taking place within the body of the developing embryo {see below). The two series of vascular channels meet, fuse, and intercommunicate. Circulation is now complete. The descendants of the haemoblasts are carried by the The Erythroblastic Line of Development 55 circulation into the liver* and spleen,-]- and proceed to give birth to a similar progeny in these regions. Changes within the Body of the Developing Embryo. For- mation of the Bone-marrow.^i — Maximow's observationsso show Extroi Vascular tissue. Vessel/ ■wclH' Fig. s2. — I/)NGiinDiNAi. Sechon of PRmmvE Blood-vessel. (;) Megaloblasts ; (2) Megaloblasts of second generation; (3) Normoblasts; {4) Red cell; (5) Endothelial cells; {6} I^ymphoid erytliroblast ; (7) Dividing normoblast ; (8) Red cell losing its nucleus. that as soon as cartilage is laid down, the perichondrium cells give rise to osteoblasts on the one hand, and wandering cells on the other. At the same time, connective tissue, carrying blood-vessels, grows * The erythropoietic function appears in the liver at the tenth day, and ceases fourteen days after birth. t The erytljropoietic function appears in the spleen at the sixth week Bizzozero and Salvioli first showed that the spleen is haemopoietic, and Dominici, Hirschfeld, and Askanazy showed that a re-assumption of this function took place in pathological states. 56 Biology of the Blood-cells in and helps to form the primitive bone-marrow.* The endothelial cells of the capillaries are isomorphous with the primitive bone- marrow cells. While the endothelial cells metamorphose, some of the connective-tissue cells fuse into osteoclasts (these dissolve the newly-forming bone round the osteoblasts and later revert into the reticular bone-marrow cells), while others appear as (i) Wandering cells like the lymphocytes of the area vasculosa — massive cytoplasm, feeble basophilia, and nucleus rather rich in chromatin ; (2) Small wandering cells of histogenic type ; (3) Inter- mediate forms. The wandering cells (i) give rise to true lytnpho- cytes. The further stages in the process of blood-formation in this region consist in the formation of erythroblasts and myelocytes from the primordial cells, which proliferate vigorously and form clumps of small polyhedral cells with homogeneous cytoplasm, smaller nucleoli, and more regular arrangement of the chromatin. The pseudopodia disappear. Haemoglobin does not appear at this stage. Ultimately the nuclei are cast out, and are devoured by endothelial and connective tissue-cells. The endothelial cells retract from one another and allow the normoblasts {see chart) to separate and be washed into the circulation. Some of the cells formed from the primordial ceUs, and some of those formed from the wandering cells, gradually metamorphose into cells with myelo- cyte nucleus, and granules appear in the cell-body. At this stage, the connective-tissue cells cease making lymphocytes, but turn into fibroblasts, fat cells, and perhaps into slumbering wandering cells. True blood-cell formation is now in full Swing. The finer details may vary after birth, but the essentials of the process remain the same. The charts on opposite page will serve to make the various processes more clear. Red-cell Formation in the Liver. — The embryonic liver may be regarded as a network of rapidly-proliferating cellular trabeculae which penetrate into a system of venous channels and give rise to bud-like processes into the lumen of the vessels, pushing ' This begins at the fourth month (EngeP'). The Erythroblastic Line of Development 57 SCHEME OF MAXIMOWS ACCOUNT OF EMBRYONIC ERYTHROPOIESIS. Perithe \ Lymph Mesoblast Cells of Yolk Sac Blood-island of yolk sac II ent) blood-ceU blood-ceU " oblast " Mesenchyme Cell in i Cell-columns Embbryo ial cell oblast Endot ecu, I become > s,^^ Bee lielial First (indifiei nay " Primitive free. " Ang Primitive blood ceU \ f hocyte . Endothelial cell II , Primitive cells ^ till loth day. (enters fcetal blood) u ames Acquires Hb. Lymp thereafter maltes X. strongly basophile Loses nucleoli. ^ Amceboid, Nucleus vesicular. = (Large) lymphocyte* cell-body small = Primitive erythroblast ' 1 (Lymp] oblast) 1 Enters >■ Iretal blood Myelo-1 ucocyte (N Definitive erythroblast Broad body with pycnotic nucleus =Priinitive erythrocyte arrow cell bodj r; vesicular nucleus) 1 Y Acquires hxmoglobm {Primitive polychromatic erythroblast) Y Polyn leucc udear cyte Y Body becomes broad ; nucleos pycnotic ; rich in Hb —Normoblast II Loses nucleua Definitive erythrocyte (enters foetal blood) "In travascular = Mitosis. =• Ageing. DANTSCHAKOFF'S VIEWS OF ERYTHROPOIESIS IN THE CHICK MAY BE SCHEMATIZED THUS: Indifferent Mesenchyme Cell Large lymphocyte Lymphoid erythroblast Erythroblast Thromboblast Thrombocyte Becomes spherical = Parent cell Mass cell ^ Lymphocjrte Round granular acidophile leucocyte Y Acidophile polynuciear cell with rod-like granules — T Splenocytoid leucocyte — ^ Plasma cell 58 Biology of the Blood-cells the lining endothelial cells before them, and leaving pockets. The ultimate result is a network of epithelial cells separating a network of vascular channels called sinusoids. From the second month on, the vascular channels are found to be full of erythro- blasts of all kinds. Haemogenesis must occur somewhere in relation to the capillary channels, and it may be either within their lumen in the pockets or diverticula formed in the manner indicated above, or it may be immediately outside their walls. We thus have the following regions in which red cells can be formed : — 1. Recesses in the capillaries of the lobule. Intravascular formation. 2. The space between the capillary and the liver cell. Extra- vascular formation. In these situations we meet with similar cells to those character- istic of red-cell formation in the bone-marrow. These cells have a dark cytoplasm, are of large size, and are continuous by proto- plasmic processes with the reticulum. They contain no vacuoles.^i^ Saxer^i'' found that giant cells (megakaryocytes) are numerous in this tissue, and they have been considered essential to red-cell formation. According to some writers, the process of haemogenesis in this tissue is the same in early as in late embryonic life, but Askanazysi"^ considers that there is a very definite distinction between the two. According to Askanazy, the red cells in the liver are not made from the endothelial cells, but from migrated myeloid elements, which ordinarily spend a " nomadic existence ; " wherever they settle they give rise to a local supply of red cells ; at any time, however, they may pass on to other regions. At a later epoch in intra-hepatic haemogenesis, the primitive erythroblasts are found to have given place to a second type of ceU (Mollier's haemoblast). This is spherical in shape, has a homo- geneous pale cytoplasm, and a deeply staining nucleus. An inter- mediate stage is passed through before the type with a very deeply staining nucleus is arrived at. Haemoglobin then appears within the cell-body, as the basophilia diminishes. Masses of haemoglobin may be seen \vithin the endothelial cells at this stage, possibly from The Erythroblastic Line of Development 59 phagocytic action on the part of these cells — but more probably from secretory action. Maximow described buds from haemoglobin- containing mononucleate cells, projecting into the lumen of the vessel. By the time that red-cell formation has reached maturity, the reticulum in which the formative cells are situated shrinks more and more from the wall of the capillary, and leaves the new cells within the blood channel by a purely passive process. Loben- hoffersi'' believed that the entry into the vascular channels was active, in that the space between the liver cell and the capillary becomes so filled up with colonies of young mitosing erythroblasts of varying size, that they are forced into the blood space ; in this way the recesses, or the sinusoids characteristic of embryonic liver tissue, are produced. It is possible that sieve-like openings appear along the walls of the capillary. Previous to the time of intercommunication between hepatic- formative islands and the vascular channels, the latter contain only yolk-formed red cells. After this period, it is evident that the blood in the liver contains hepatic blood-cells and marrow-cells in addition. When the yolk-cells cease to be formed, the blood contains only the hepatic and marrow red cells. By the seventh month, the sieve-like communications have closed up, and red-cell formation in the liver begins to subside. Red cells are first formed in the liver at the tenth to the twelfth day in the rabbit ; in man, at the end of the first month. The process ceases about a fortnight after birth (Kostanechi^i^). Goodall^i' foimd that red-cell formation in the liver precedes leucocytogenesis in the sheep. Red-cell Formation in the Spleen. — The spleen commences its activity at a later period than does the liver — about the sixth week. The tissue contains numerous giant cells, and haemoblasts, which proliferate actively. There is evidence to show that the indifferent specific splenic cells themselves give rise to haemoblasts for a certain period of the life of the individual. This is specially marked in the lower vertebrates.^i^ There is no red-cell formation in the spleen after birth, except under pathological conditions ; the later phenomena in the spleen are rather those of myeloid transformation. 60 Biology of the Blood-cells Red-cell Formation in Lymph Nodes. — In one case of acute haemorrhagic macrolymphocytar leukaemia, reported by Pappen- heim.si" it was found that the mother cells of the venous inter- foUicular tissue gave rise to red cells. If this finding is to be regarded as more than of passing interest, it indicates that erythropoiesis can take place in the lymphoid tissues even in post-embryonic life. Fig. 23. — I^YMPHOID ERVTHROBLASTS. a, Intermediate stage between parent cell and , b, I^yinphoid erythroblast. (See note to Fig. 8). WhCU the primordial Cell acquires characters which place it with the hsemoglobin-forming series, it is found to have undergone nuclear metamorphosis. Here, as wiU be found to hold with the other cell series, differentiation goes hand in hand with change of nuclear character. Characters of the Lymphoid Erythroblast.— The characters of the cell, now called lymphoid erythroblast, are as follows {Figs. 23 and 22) : — Size. — 6-9 /J. Shape. — Round, with regular and well-defined contour. Cell-body. — The cytoplasm is basophile, and devoid of any granules, devoid of circumnuclear zone or astrosphere. The amount of cytoplasm is small. There is no haemoglobin. Cell-gramiles. — No azure granules. Nucleus. — Central in position, round, relatively large (2-4 fj-), clearly defined. The chromatin is arranged in characteristic form — the so-called wheel structure, since the parachromatin and chro- matin alternate at the periphery of the nucleus. Nucleolus. — None.* * The fate of the nucleolus during the conversion of the primordial cell into the erythro- blast. — ^The following possibilities require to be discussed : (r) That the nucleolus is cast out. In favour of this is the presence of such bodies both free and within the bodies of phagocytes ; (2) That it turns into oxychromatin, and ultimately takes part in the forma- tion of haemoglobin ; (3) That the nucleolar matter is admixed with the chromatin, thus accounting for the altered tint of the nucleus with azur staining— ordinarily purely basophile. In embryonic myeloid tissue there are seen lymphoid erythroblasts without haemoglobin, but with nucleolus, the nucleus already showing radial structure (promegaloblasts). The Erythroblastic Line of Development 61 Mitosis. — Frequent. The cells are very basophilic. Appearance with Ultra-violet Light. — The characteristic radial structure of the nucleus is well deinonstrated,32 and the dark bands are extremely opaque to the rays. The cell-body, on the other hand, is quite homogeneous (distinction from the white cells). Characters of the Megaloblast. — This cell presents consider- able variations in aspect with increasing age, owing to the fact that it is first polychromatic and finally ortho-chromatic. In other words, the amount of haemoglobin in the cell is scanty to begin with and produces an anomalous colour effect with the ordinary dyes, while the mature cell is rich in haemoglobin, which then stains strongly red with eosin (orthochromatic). The megalo- blast is already a biconcave cell.^s The characters are best tabulated, thus : — Orthochromatic Megaloblast Polychromatic Megaloblast Engel's metrocyte of Engel's metrocyte of the first generation the second generation Size . . 10-20 fl Less Less Cell-substance Scanty . . Strongly poly- More abundant More abundE^nt chromatic Shghtly Not at all Granules (Winkler- Schultze) Presents^ Present Not observed Nucleus Large .. Large Small Rich in structure Rich in structure Very darkly staining Does not pycnose Does not pycnose Pycnoses Nucleolus Present3« No .. No Multiplication . . By mitosis By mitosis By mitosis Other forms . . Gigantoblast Micromegaloblast* • ~ Physiological properties Amoeboid t No .. No Pathological Premature expul- change sion of the nu- cleus Ditto Ditto Fate . . Becomes metrocyte Becomes metro- Becomes normo- ist gen. cyte 2nd gen. blast * The prematurely denucleated erythroblast is an atypical form, t Thayer. 62 Biology of the Blood-cells Other cells which belong to the same group, are the secondary erythroblasts (small, medium, and large forms). Chemistry of the Erythroblast. — The use of vital stains reveals the presence of vivid red granules (neutral red) of acid reaction, and the nodal intersections of the reticular network (substantia reticulosa) stain of a brownish colour. The acidity is due to the presence of free oleic acid, probably associated with a lipoid exudate from the nucleus.^'' /"> © a, Fig. 24. — Diagram of the .Megaloblast Forms, a, Polychromatic; b, Orthodiromatic form, first generation; c, Ditto, second generation (compare with the tabulated description). The mechanism of the formation of hsemoglobin has been worked out to be the effect of diffusion of the parachromatin (nucleic acid) from the nucleus into the spongioplasm. The nuclear material meets with amino-bases in the latter, and combines with them to form hcemoglobin (Loele^s). This explains why the wheel structure of the primitive cells gives place to the peculiarly densely-stained chromatic mass of the pycnotic normoblast. It is noticeable that the polychromatism becomes less and less (ortho- chromatism becomes greater and greater) as the nucleus becomes darker and denser. The interspongioplastic haemoglobin appears, as the pale streaking within the nucleus disappears. There has been much discussion as to whether the megaloblast, for instance, is rich or poor in haemoglobin. According to Hirsch- feld, this cell contains as much haemoglobin as the other red cells, because triacid staining does not justify any other conclusion. May-Giemsa gives so polychromatic an effect that the haemoglobin tint is masked. Pappenheim considers the megaloblast to contain little haemoglobin, because (a) polychromasia means poverty in Hb, (b) giant megaloblasts are definitely basophile.* * Here, as in so many subjects of dispute in hasmatology, the final conclusion is nothing more than an expression of personal opinion. There is as yet no fact which shall definitely say that polychromasia is or is not dependent on Hb-defect. The Erythroblastic Line of Development 63 Differential Diagnosis of the Megaloblast. — From the leucocyte. Pycnotic megaloblasts may simulate polynuclear leucocytes. The^ nuclear structure should be studied. The pycnotic nucleus is quite devoid of parachromatin. From the Turk cell. Note the relative size of the nucleus (compared with the cytoplasm). It is small in the Ttirk cell. The cytoplasm of the latter is intensely basophilic, and is vacuolated. The nucleus is amblychromatic. From the myelocyte. If the megaloblast shows chromatinolysis it may simulate the myelocyte. The presence of haemoglobin in the megaloblast would be sought for. Views as to the Nature of the Megaloblast : — 1. That it is degenerative. — (a) That a blood-borne poison, acting on the cells, causes a change in the haemoglobin ; (b) That it is the effect of a blood-borne poison acting on the marrow cells (Bonniger, Naegeli, Erik Meyer, Bloch) and causing them to make aberrant cell forms. K. Ziegler and Isaac and Moeckel regard the appearance of megaloblasts and megaloblastic degeneration of the bone-marrow as a direct result of the action of the poison on the marrow, and itself an evidence of myelotoxicosis. 2. That it is regenerative. — {a) That a blood-borne poison acts on the marrow and excites regeneration (embryonization, Ehrlich) without differentiation into normoblasts, etc. The progress of development is set in motion but arrested at the megaloblast stage. (Naegeli, Erik Meyer, Engel, Pappenheim). (b) That it is entirely normal erythropoiesis (Grawitz). (c) That it is a response to a severe injury to the bone-marrow, or, sometimes, to the blood. If these cells are numerous in the bone-marrow, then it must be a pathological condition (Tiirk). It is the product of exhaustion of an already asthenic marrow, after hsemotoxic influences. The myelotoxicosis, however, is not the cause of pernicious anaemia.^^ (i^) That it is the normal process of red-cell formation in the embryo (Ehrlich). However, embryonic tissue contains both megaloblasts and normoblasts. Post-embryonically, too, both megalo- and normoblasts occur together. 3. That it is a swollen erythrocyte (Mya). — This is not likely, because it would demand a structure of cell different from that 64 Biology of the Blood-cells of other cells which cannot be made to swell by osmosis. On the other hand, when the blood is rich in megalocytes, it is poly- plasmic, so that some large red cells have arisen by swelling. 4. That it is a purposeless and inevitable result of action of some noxa {a) on the bone-marrow, regardless of kind, but dependent on degree ; or (6) on the blood, with or without action on the bone-marrow, according as the latter does or does not undertake regeneration.* The Characters of the Normoblast. — Size. — 7-9 ju. Shape. — Spherical, not biconcave. Cell-body. — Homogeneous, non-granular, and yellowish-green in colour (with methylene blue). Nucleus. — Relatively small, sharply spherical and central. Stains densely, and presents the characteristic wheel structure. Pachychromatic. Nuclear membrane well marked. Nucleolus. — Present according to Schilling.s^ Multiplication. — By mitosis. Degenerative Changes. — Pycnosis of the nucleus and free nucleus formation. Chemistry of the Normoblast. — The process by which the basophile cytoplasm of the megaloblast gives place to the erythro- philic hsemoglobin-containing cell substance must lie in a chemical " metaplasia " of the paraplasm, associated with a loosening up of the spongioplastic network. In certain toxic anaemias, the basophile cytoplasm clumps up into masses which appear as punctate basophilia, during the time that the cells are circulating.^o Differential Diagnosis of the Normoblast : — From a lymphoid cell. The rule may be formulated that if a lymphoid cell have a nucleus like a wheel, or like a densely chromatic (pycnotic) mass, then it is an erythroblast or haemoblast. This covers the difficulties of diagnosis of the parentalj^lymphoid cell, as well as of the polychromatic or (pathological) basophile normoblasts from lymphoidocytes, large mononuclears, leucocytoid lymphocytes. The peculiar greenish tint of the erythroblast * This view is somewhat similar to that of Tiirk. The Erythroblastic Line of Development 65 cytoplasm is a frequent help in diagnosis, besides the facts that the cytoplasm is relatively more abundant, and that the nucleus is only slightly excentric, if not truly central in position.* The Birth of the Red Cell into the Blood-stream. — We have traced the sequence of changes which take place in the process of conversion of the primordial cell into the normoblast. It has been indicated that the cell-substance becomes more and more abundant, looser in texture, and more definitely reticular in structure, while the nucleus still remains characteristically lymphoidocytar ; that the nucleusf then exhibits a tendency to radial arrangement at the same time as an oxyphile parachromatin appears within it ; while the cell-body develops homogeneity of structure, with alteration of staining power simultaneously with the commencement of formation of hiemoglobin. The delicate outlines of the lymphoido- cytar cell become replaced by the more definite and clean-cut contour of the normoblast. Finally, the radial structure of the nucleus, ultimately well-marked, disappears again with the increase in the amount of haemoglobin formed within the cell-body, while the shape of the nucleus alters, becomes polymorphous (pycnotic) in consequence of the shrinkage of the material within it. Before the red cell is " bom " into the circulation, it loses its nucleus. The mechanism by which the loss of nucleus takes place is one of the subjects of controversy in hsematology. t We have the following possible explanations of the process. 1. Either it is not lost at all (Schilling), only the chromatin having disappeared : 2. It is cast out : 3. It is dissolved out (chromatolysis, karyolysis) : or 4. It is partly dissolved, and extruded in that condition. || I. The first view may be correct in some instances. If chromatolysis take place, the parachromatin remains in the cell, • This is by no means invariable. t An alternative view (Freytag*"* ; H. C. Ross"), that the nucleus appears first, and develops a cell-body around it, finally giving rise to a red cell, hardly deserves mention. X Probably because some observers studied healthy and others pathological blood, and considered the difference beneath notice. II Artificial denucleation may be induced by boric acid, urea, tannin, etc., applied to the wet preparation* "I". 3 «6 Biology of the Blood-cells and the last stage before complete loss would be represented by the Jolly body {see p. 83), which may never be extruded at all. The oxyphile nuclear masses which have been described as occur- xing in red cells would represent the parachromatin.^i Further, the fact that a nuclear body can be demonstrated in nearly every red cell in man, by a methylene-blue-picric-acid method, is of interest. (Plate II, No. 7). 2. The second view was held by Rindfleisch, but was regarded by Ehrlich as holding only in the case of the normoblast, and not for all nucleated red cells. Engel accepted it only for the poly- ■chromatic normoblasts. Maximow accepted it entirely, and Pappenheim considers it is a pathological process due to errors of tonicity (anisotonia) of the serum, being met with only in the case •of those erythroblasts which enter the blood-stream instead of remaining behind in the bone-marrow till their development is completed. According to this author, it is quite incorrect to assign a different mechanism for the loss of nucleus to different red-cell parents. The megaloblast is similar to the normoblast in nuclear ■structure, and in the senile changes to which it is liable ; it differs only in that the normal process of ageing does not go as far as the production of erythrocytes. Pycnosis, chromatolysis, and karyor- rhexis only occur in the megaloblast under pathological conditions (see chart, p. 68), although they then follow the same rules as hold good in the normoblast. There is therefore no logic in saying that the normoblast loses its nucleus by extrusion and the megaloblast by karyorrhexis : — Normal Process. — No megaloblasts. Normoblasts present. These show chromatolysis of pycnotic nuclei. Pathological Process. — ^Megaloblasts present ; show karyorrhexis ; normo- blasts also show " rhexis." The arguments against the second theory are : the existence of Jolly nuclear rests within the red cells ; the existence of Cabot's membranes ; the absence of free nuclei in the bone-marrow. If the nucleus be cast out, what becomes of it ? It may be subjected to phagocytosis in the bone-marrow, since macrophages are often seen there, which contain nuclei but no blood-pigment {Jolly). On the other hand, macrophages may devour whole red The Erythroblastic Line of Development 67 cells without betraying such an event by pigment-granule deposition (R. Blumenthal). Secondly, it may break up into coarse particles (" punctate basophilia," see p. 78), which ultimately dissolve within the cell. 3. The third theory is accepted by Neumann, Kolliker, Engel ; and by Ehrlich for the megaloblast. Pappenheim considers that this change takes place normally within the blood-cell factories, though especially marked in severe toxic anaemias (conspicuous because met within the circulating blood). It is the normal pro- cedure after pycnosis of the nucleus has taken place, the shrinkage of the latter having ended with the formation of the small granule, the Jolly body. According to Weidenreich, this body is ultimately extruded. The loss of nucleus must occur before the cell leaves the bone-marrow at all. Blumenthal has pointed out that an alteration of osmotic relations between plasma and formative cell would accoimt for the disappearance of the nucleus without obvious precipitation phenomena in the cell. The pressure is greater in the blood than in the areas of haemopoiesis, and the cells are more turgescent at the time of mitosis. 4. The fourth theory is held by Engel in the case of the pycnotic normoblast. The best mode of co-ordinating these views* is as follows : — Description Site of Cell State of Nucleus AT the time Last Stage Occurs in Normal Bone-marrow Pycnotic Chromatolysis Health Abnormal Blood Partly pycnotic Extrusion Simple anaemia Frankly Both blood (i) Pycnotic . . Karyorrhexis Severe patho- and bone- (ii) Juvenile and acute logical marrow . . non-pycnotic toxic anaemias. As soon as this change is effected, then, the completed red cell finds itself swept into the blood-stream. Why it should be able to enter at this stage, and not before, is unknown. All that we can say is that the cell has now arrived at " blood-maturity." * Pappenheim's exposition of these views is more graphically expressed when crystallized in the manner given. o cu o X H u z o > a a o Oh z o > s 2 •< u s u Z u is t 1-5.2 I o 11 |. 11 offl't 3 « 6 C II » >.'o pooiq i^DiaoiomBj Life History of the Red Blood-corpuscle 69 III.— THE LIFE HISTORY OF THE RED BLOOD-CORPUSCLE IN THE BLOOD-STREAM. Characters of the erjrthrocyte — The theories regarding the structure of the red cell — The chemistry of the red cell — The fate of the red cell — Degeneration phenomena — The evidence of destruction of red cells — The reticular sub- stance — Polychromatophilia — Punctate basophilia — The Heinz bodies — Red- cell shadows — The Howell- Jolly bodies — ^The Cabot ring bodies — Chromo- linin granules — The blood-platelets — Hyperchromia — Alterations of shape and size — ^The comparative morphology of the red cell — The spindle cell — The haemokonia or blood-dust. The blood of the normal infant contains at birth six million red cells per c.mm. This number decreases with age to about five and a half by the end of the second week of life. The adiilt blood contains about five millions per c.mm. in the case of the male, four and a half millions in the case of the female. Characters of the Erythrocyte. — The red cell, erythrocyte, or normocyte, is a thin flattened disc, slightly concave on one side, more so on the other. According to Weidenreich, mammalian red ceils are dimpled on one side and slightly convex on the other (bell-form) ; the biconcavity usually seen is regarded by him as the result of accidents during preparation (evaporation).'i2 Against this view is the observation of the cells in the circulating blood (mesentery, e.g.).* The outline of the red cell is regular, and its surface smooth. It is very elastic. It owes its colour to the presence of haemoglobin. According to Sapegno, it contains Winkler-Schultze granules. Size. — This is very uniform in normal blood, 75 per cent of specimens measuring from y^ to 8|- fi ('007 to -008 mm.) by 1.7 fi in thickness. Nucleus. — It is usually stated that there is no nucleus in the red cell of man. According to Roscoe King, every red cell has a remnant of nuclear matter within it,6i and Schillings? has demon- strated that there is a definite nuclear structure in every cell, though it has so slender a connection therewith that it is lost in ♦Sehafer," David,*' Jordan," Jolly," Orsos," Lohner.™ 70 Biology of the Blood-cells the form of blood-platelets in the course of ordinary preparation. Kronberger^i has recently shown (1912) that " nuclei " can be demonstrated in any red cell by a simple method of staining (methylene-blue, picric acid). (Plate II, No. 1.) Glass-body* — Schillings^ has described a peculiar structure within the swollen red cells in malarial blood, having a spherical shape, devoid of haemoglobin, and containing a vacuole in which lay two very minute granules. The granules stain black with osmic acid, red with chromatin dyes, and are strongly refractile in the unstained condition, greenish-yellow ^ — ^ with dark - ground illumination. These '^""^ I granules were regarded by Schilling as * '~"^Bi / centrioles. c—^^[ I Subsequently he was able to detect A-X- I 1 them even in normal erythrocytes. -%w I Diazin-green demonstrated the presence \^_r/"^ of platelets adhering to the red cell by Fig. .5.-scH,.Lm«'s cox- "leaus of a delicate membrane. Lieber- wS^teLel w BioXifeut'; kuhn54 regards this as a protein spherule.f [|Sbod^1'',.Tc^tri^2'S This conception of the red cell may fiS poraSni *" Hffi^ogiobm-hoid- ^^ expressed in the accompanying diagram {Fig. 25), which shows a body flat on one side, and convex on the other. The convexity is due to the " glass- body," which is ordinarily invisible, leaving an apparently biconcave haemoglobin-bearing part. In one comer of the glass-body is the nuclear remnant, with a " capsule-body " covering in the nucleolus. Adjoining this are the centrioles, with the centrosome,t part of which is usually lost in preparation as a blood-platelet. Benda and Jordan^s consider these appearances as artefacts, even though they are seen with dark-ground illumination. Jordan's criticism is based on observations of the red cells in the living cat whUe narcotized with ether. * First found by Roberts.'' Not accepted by Dietrich.'"* t A platelet may, however, be looked on as a proteiii spherule. I Centrosome + capsule-bodj;, by accumulating plastinoid chromatinic substances, may appear as pseudopodia (Schilling). According to Walker, Ross and Moore," 5 per cent of red cells can be made to show the presence of a centrosome if an absolutely refined technique be followed. Life History of the Red Blood-corpuscle 71 The Stroma of the Red Cell. — ^The existence of a hyaline network within a red cell (substantia granulofilamentosa), made of nucleoproteid, in the meshes of which lies the haemoglobin, has been accepted by some (RoUetts^), and rejected by others (Schafer^T). The fact remains that some red cells do contain a vitally stainable substance* in the form of a network, which is the more abundant the younger the cell. It stains blue with Nile blue {see f. 75). Ultra-violet light, according to Grawitz and Griineberg, shows no such reticulum in any erythrocyte. It is moie satisfactory in many ways to look upon the red cell as made of a semi-permeable membrane (H. Koeppe) with a spongy network of reticular substance, enclosing aqueous haemoglobin within its meshes. The network would be colloidal, and possibly not anatomical in the strict sense. The membrane is covered by a film of lipoid material, in which lecithin and cholesterin are prominent. The Theories relating to the Subject are these : — Griesbach : — That the red cell consists of a homogeneous structureless plasma and no membrane. Weidenreich and Dietrich consider the red cell to be merely a bladder whose contents, the endosoma, contain the pigment, while certain agents may lead to the formation of precipitates within the envelope, and so simulate , a " reticular substance." Fischer found that fixatives, such as osmic acid and mercury perchloride, would cause extracellular haemoglobin to aggregate into flakes, thus simulating punctate basophilia and reticular matter. This view was accepted by Grawitz on the basis of observations of the red cell with ultra-violet light, wherein the cell is homogeneous. If the red cell be only membrane + contents, the " membrane " has still to be defined. Lohner'^' divides membranes into : (i) Physical : (a) surface scum, (6) plasmatic film ; (2) Histological. He suggests that the cell membrane is only a physical one (plasmatic film) . The Stroma Theory. — Schultz expressed the view that there is a lecithin- stroma of ultramicroscopical structure, in whose meshes lie a watery solu- tion. The jelly-like stroma maintains the haemoglobin in an absorbed state. The full bearing of this view requires an appreciation of the phase-doctrine of Ostwald. Schafer is a strong opponent of this theory,™ stating that it " must be definitely abandoned." The chief argument against it is the character of the movement of the red cell within the capillaries. In the nucleated red cell of the lower vertebrates, the nucleus is always readily displaced within the • First discovered by Ehrlich, " Farbanalytische Untersiwhungen,'' pp. 98, 119. 72 Biology of the Blood-cells Ted cell, which would not be possible with a stroma. For these reasons he disbelieves even G. N. Stewart's view,'"^ that the haemoglobin is in the fonn of a gel. The explanation of this divergence of opinion must he in some such fact as was adduced in connection with the dispute about the manner of loss of the red-cell nucleus. The exact structure of the red cell may vary in normal and pathological blood ; the so-called stroma may be an optical effect pro- duced by a colloidal mixture, just as the spongioplasm of any cell may. It does not seem Ukely that a red cell is a sac containing anything approaching watery material, and those who are satisfied with such a view apparently overlook the laws of colloidal chemistry. The view expressed by Schultz is therefore by far the most likely. The red cell with dark-ground illumination. It shows perfect homogeneity of structure under these conditions — a round bright ring with sharply-defined dark centre. Crenate, swollen or burst erythrocytes are easily seen by this method (Dietrich®^). The vital staining reactions of the red cell are best considered in conjunction with the processes of degeneration {see p. 75). The Chemistry of the Red Cell. — It is not proposed to discuss the chemistry of hamoglobin, since this subject belongs to the domain of pure physiological chemistry. As is well known, the gas-exchange function of the red cell depends on the presence in it of this substance. Regarding the question of the lipoid material within the cell, Overton's observations may be referred to, that the red-cell membrane is covered by a iUm of lipoid material, which is made up of cholesterin and lecithin* (Norris's " myelin "^s), and encloses the haemoglobin in watery solution. The following considerations go to show this : (i) The phenomena seen in haemo- lysis by saponin. One may add, that all hsemolytic reactions are best explained in this way : ether, chloroform, immunity re- actions ; (2) Corpuscles melt at 52° to 60° C. ; (3) The formation of rouleaux ; (4) The indentation of the membrane by protozoa striking it ; (5) The fact that mechanical rupture of the red cells leaves no sign of any hole ; the fatty material immediately flows in around the point of rupture and obliterates it. Grawitz suggests^* that the fine particles of fat in the circulating blood (which can be seen with dark-ground illumination) are taken up • Drops of fluid enclosed in lipoids assume a flattened shape. Life History of the Red Blood-corpuscle 73 by the red cells and appear to us as lipoid envelope, to be afterwards given up to the tissues wherever needed (e.g., to working muscle, which requires a rapid supply of energy-producing matter). This idea of a second function of the red cells may be contrasted with Pavy's view of the function of the lymphocytes {see p. 139). Percentage composition of the red cell in man (Bunge^s) : — Water . . Haematin Organic compounds Potassium salts . . Sodium 68-2 1-5 29-6 0'6l 0-03 Calcium and magnesium phosphates o-oi6 Glucose is stored up in the red cells in cases of alimentary glycosuria (Rona and Takhaschise). The mode of formation of haemoglobin has already been con- sidered {p. 62). The presence of oxydase in the red cells of frogs and birds was detected by Pappenheim. The osmotic and physical phenomena of red cells (rouleaux formation, specific gravity, resistance of red cells in haemolysis) do not come within the scope of this work, since their description involves the detailing of many purely physico-chemical laws.* The Fate of the Red Cell. Degeneration Phenomena. — It is evident that in any one drop of blood, red cells of all ages must be present. If it be possible to determine the average duration of life of each, the knowledge would be of service. The following estimation, by Zoja.^^ shows that the normal length of life of a red cell in the circulation is about ten days. Other estimations place it at three to four weeks. Assuming that the total amount of blood is ^V of the body weight, then in an adult weighing 70 kg. there will be 5384 gm. blood (= 5080 c.c). Again, assuming that 600 c.c. of bUe are secreted daily, 0-35 per cent bilirubin is present in it, and 1377 per cent by weight of haemo- • It will suffice to note that the resistance of red cells is increased (i) after injection of homologous blood, (2) after treatment with phenylhydrazin in vitro ; that such increase of resistance is accompanied by an increase in the^ amount of stroma (Sattler ; Ferrata)'^. The last statement is disputed by Rosenthal. " 74 Biology of the Blood-cells globin in blood; further, assuming that the total formula of bilirubin is C„Jii„e'i^jC>„ then Zinowski's equation allows an estimate of the amounts of haemoglobin broken down and the red cells destroyed. The result is : 62-83 gram haemoglobin and 420,000 reds per c.mm. In twenty-four hours, a tenth of the total of each is destroyed. In other words, the total cell-content is renewed every ten days. How does the red-cell content of the blood remain constant ? Roux and Driesch endeavoured to solve this problem by adducing chemical and physico-chemical data, and the biological equilibria of Centanni. If the normal equilibrium be upset, a new one arises which is more or less effective, and depends for its efhciency on the factors previously existing. The condi- tions depend on the circumstances which led to the disturbance of the original equilibrium, as well as on the new circumstances arising by the action of the factors inducing it (Zoja). Assuming that the destruction of the red cells gives rise to autocytolysins which excite a corresponding degree of cytopoiesis in the hemopoietic organs, we see here an automatic mechanism for regulating the content of red cells. The intermediate stages between "robust health" and destruction of the red cell in the liver, spleen, etc. (reappearing as bilirubin, or, pathologically, as "siderosis") are difficult to demon- strate. Some of the red cells are removed from the circulation by phagocytosis (erythrophages) in the spleen,* bone-marrow, and lymph-nodes, but there is no evident difference in the appearance of a red cell about to be phagocytosed, and one that is apparently in full activity. On the other hand, such changes may be noted as these — shrinkage, development of polychromatophilia, loss of haemoglobin, flattening out of dimple. Pathologically, a number of changes are observable which may be interpreted as intermediate stages of breakdown, but these stages are evidently not passed through under normal conditions. Evidence of Destruction of Red Cells. — I. Alterations of Morphology. Cesaris-Demel's reticular substance. Note the relative propor- tions between cells exhibiting same, and those not. * The histolysis of red cells in the spleen passes through all stages towards a granular pigmentary detritus. In animals with nucleated red cells, the nucleus loses its affinity for basic dyes, and gradually dissolves away. At the same time, the cell-body fails to stain adequately with eosin or acid fuchsin (Blumenthal"). Life History of the Red Blood-corpuscle 75 Polychromatophilia. Proportions between platelets and whole red cells. Punctate basophilia. Jolly bodies. Cabot's rings. Presence of normoblasts, microcytes, macrocytes, poikilocytosis, fragmentation of cells. Alterations in the stroma : hypochromia, dyschromia (baso- philia), true necrobiosis. Alteration of the haemoglobin : increased oxidizing power, conversion into met-haemoglobin. 2. Alterations of the resistance. This is greater the younger the cell. 3. Presence of bilinogen in the urine and faeces (estimation by chloroform extract by Riva and Zoja's method^s), in respect to the ratio between its quantity and that of the haemoglobin. The Reticular Substance. — The presence of reticular sub- stance within red cells is demonstrated by the use of vital stains. Vital staining* is really a pre-agonic staining, because the material coloured takes up the dye just before death takes place, the staining agent being toxic in action. The reticular substance is a filamentous material beaded with granules.f the latter coming out meta- chromaticaUy. Nile-blue, toluidine blue, neutral red, cresyl blue, are suitable dyes for colouring this substance, the reaction with the former showing that the material is made up of free fatty acids.^ According to Cesaris-Demel, it is identical with basophile punctation (which see) ;''^ but Pappenheim, Rosin, and Weidenreich are opposed to this view, since they regard it as related to polychromatophilia — a phenomenon met with as a regenerative process, appearing as it does after repeated venesections in animals (Ferrata^a). The material is not nuclear, but plasmatic in character, because in embryos and young animals its abundance is not associated with the appearance of changes in the nucleus. • Vital-staining is regarded as evidence of youth by Poggi, Vassale, Negri, Fok, Cesaris- Dcmel, Giglio Tos ; as evidence of increased resistance of the cells by Widal, Abrami , Chauflard-Fiessinger ; as identical with basophilia by Rosin, Biebergeil, Weidenreich. t The granules show Browniau movement. 76 Biology of the Blood-cells EXPLANATION OF PLATE II. 1 . — Polychromatic gigantocyte. 2. — Polychromatic megaloblast. 3. — Polychromatic pycnotio macronormoblast. 4. — Polychromatic young normobast. 5. — Orthochromatic young normoblast. 6. — Lymphoid haemoblast. 7. — Red cell of normal blood stained to show the "nucleus" within it (methylene blue and picric acid). Figures 1 to 7 are drawn to scale. 8. — Punctate basophilia in a polychromatic red cell. 9.^ — Red cell showing substantia granularis metachromatica and the reticular substance. Note the metachro- matic staining of the Heinz body with azur (after Pappenheim). 10. — Red cell showing a Cabot ring. 1 1 . — Red cell showing chromatinorrhexis. (8 to 1 1 are highly magnified. 1 and 1 1 are after Ferrata and Viglioli. Panoptic stain). 1 2. — Poikilocyte (medium size). 13. — Microoyte. 14. — Macrocyte. (^3 and 14 are drawn to scale.) Red cells from various infra-mammalia : 1 5. — From Carabus hortensis, a beetle (triacid) x looo. 1 6. — Scyllium, Giemsa (after Fry). 17. — Petromyzon, Triacid. 18. — Emys lutaria, Panoptic; the hajmoglobin is polar in situation. 19, 20. — Rana temporaria. Panoptic. 21. — Triton, Panoptic. 22. — Spindle cell from Triton ; stained by Unna-Ziehl. (17 to 22 after Werzberg, and approximately proportionate in size). 23, 24. — Orthochromatic and polychromatic erythroblast from sparrow, passer domesticus ( X 700). 25. — Normocyte with pycnotic nucleus, from domestic fowl artificially rendered severely aniemic. After Kasarinoff. < Highly magnified). 21 PLATE II. THE RED BLOOD-CELL iJ^'' >. '^ V-? 1^ t & Biology of Blood-cells O. C. Oi liner Life History of the Red Blood-corpuscle 77 Pappenheim," in 1907, decided that the reticular substance was rather of the nature of a dye-precipitate upon the surface of the lipoid membrane (adsorption of the dye by the lipoid). This view was independently arrived at by Biondi.'* The fact that a fresh vital-stained preparation, treated with active snake-venom-lecithid, dissolves the red cells, leaving the reticular substance free," is quite suggestive. Occurrence. — ^Very abundant in embryonic blood, fairly abundant (30-40 per cent) in the new-bom animal, and scanty in the normal adult animal. It occurs both in circulating erythrocytes and in the normoblasts of the bone-marrow. It is met with in the blood in cases of haemolytic jaundice (Chauffard, Fiessinger^s), and of progressive pernicious anaemia (Widal and Abrami'^^). Significance. — As has been stated, there is evidence that the phenomenon is indicative of normal regeneration ;* it is frequently associated with polychromatophilia.f Since it can be specially weU studied in the red cells of tertian malaria (Schiiffner,''8 Maurer^a), it is presumably connected with regeneration of the blood, and is not an artificial effect. The appearances described by the last- named authors have nothing to do with punctate basophilia (see below). 80 J PoLYCHROMATOPHiLiA. — By this term is meant a morpho- logical change in the red cell whereby the basic and acid components of a dye-mixture are taken up at the same time. A mosaic work may be imagined, in which alternate minute fields are basic (the original basic material of the parent), and the remainder contain haemoglobin. As has been seen, this phenomenon is nothing more than a phase in the ordinary maturation of the red cell.si Apart from this, polychromatophilic cells may be seen in the blood of pigeons, mice, guinea-pigs, cats and dogs (Walker), frogs (Grawitz), but not in normal horse or ox blood. The close association with the reticular substance has led Schilling to regard the two as identical.^T • In pernicious anaemia it is the anisocytosis and the presence of megaloblasts which indicate pathological regeneration. t Schilling maintains that the two are identical." JThe Maurer-SchUfiner punctation is a degenerative basophile polychromatophilia. It never occurs except in intoxications, and is not an embryonic process at all (Pappenheim). 78 Biology of the Blood-cells but others regard the two conditions as unrelated, although frequently met with side by side (Ferrata and VigUoli).8i The following views have been expressed : (i) That these cells are not degenerative (Gabritschewsky, Askanazy, Arneth, Pappenheim^z). Proofs : (i) They are very abundant after a hasmorrhage ; (ii) They occur in foetal liver in the seventh month. {2) That they are degenerative — cloudy swelling, old age, etc. (Ehrlich, Engel), or, possibly precursors of punctate baso- philia (P. Schmidt and Askanazy). Proofs : (a) Other red cells in a film show signs of degeneration ; (6) They are abundant in starving animals, where the bone-marrow shows no signs of activity ; (c) The strongly poly- chromatic cells have irregular contour ; (cC) Megaloblasts are always affected and normoblasts are not (Maragliano, Castellino, Ehrlich) ;* (e) They are very numerous after the exhibition of blood-poisons. | (3) That they are provisional blood-cells (Engel). (4) That the first two views may each be correct (Rechzeh, Tiirk, Weidenreich, Grawitz, and Pappenheim). In other words, it may be sometimes a progressive process, at others a regressive process, the latter being by far the rarer. As Weidenreich has said, if the •oxyphilia be due to haemoglobin, and basophilia to the membrane, then a deficiency of hasmoglobin makes the cell appear more basophile equally in youth and in disease. In one case the hasmoglobin has not yet appeared, in the other it has disappeared. The so-called azurophile polychromatophilia is a pathological process, and is regarded as being due to fragmentation of the chromatin. In other words, it is definitely nuclear and not plasmatic in character.^s The polychromatophilic red cell differs from a lymphocyte in being poorly stained, in the absence of a basophile film of cytoplasm, and in the absence of a definite nucleus and nucleolus. Comparison with other cells in the blood-film will prevent mistakes. Punctate Basophilia (basophile punctation, granular de- generation) is a term applied to red cells in which there are fine basophile granules of varying size. Such cells are met with in the blood of birds, of the new-bom guinea-pig, mouse, and rabbit,! in the human embryo, and in the human adult in certain anaemias (secondary to ulcerating gastric and oesophageal cancer, lead * But the megaloblast is an immature cell, and would naturally appear polychromatic, t It does not follow that because blood is poisoned, regeneration of red cells does not ever develop. J Denied by Grawitz, Griineberg, Bloch, and H. Konig. Perhaps such embryos were diseased, and this would remove the argument that basophilia is regenerative in character. Life History of the Red Blood-corpuscle 79 poisoning,* poisoning by salts of tin, copper, potassium chlorate, mercuric chloride, pyrodin, phenylhydrazin, septic infections, malaria, bothriocephalus, intestinal intoxications, and in primary pernicious ansemia).! Such cells are not met with in health, in infants, nor in such anaemias as chlorosis, post-haemorrhagic (external), aplastic, tuberculous, syphilitic, chronic nephritic, chronic hepatic, diabetic, nor in the course of acute infections like typhoid and diphtheria.^ Cells in which punctate basophilia may occur, (i) In poly- chromatic erythrocytes (as fine granules) ; (2) In orthochromatic er5rthrocytes (as coarse granules) ; (3) In mitosing cells. Theories as to the nature of the condition : — 1. Is it a true granulation ? It is not analogous to leucocyte granules, because the latter are a mature end-product of the para- plasm, and represent the functions of the ceU. Leucocyte granules are analogous to haemoglobin. Punctate basophilia, on the other hand, indicates incomplete development of the cell and is spongio- plastic in character. 2. As regards source. (i). Is it nuclear ? Askanazy and Lazarus|| regard it as a karyolytic process. Ferratas* regards the material as parachro- matin, because it is close to the nuclear membrane, and is always associated with karyolytic changes in the nucleus, and sometimes with Jolly bodies or Cabot rings. Naegeli believes it to be chromatin which has undergone a change in staining reaction, by which methyl green interacts with it. Against Ferrata's view are the facts : (a) That parachromatin may be found amongst the fragments of nuclei in a cell without entering the cell- body ; (6) That basophilia may occur without Jolly nuclear rests ; (c) And with them. Bollke^** considers that the granules cannot be parachromatin. because they occur in mitosing cells (which contain none). The other * First discovered by Grawitz and Hamel. t Ehrlich. } The condition must not be confused with the appearance of nuclear chromidial fragments arising from karyorrhexis. These stain red with azur, and blue-green with methyl-greeu-pyronin, purplish with hsematoxylin. II Schaumann, Engel, Sabrazds, Jawein. 80 Biology of the Blood-cells objections to the above theory are at the same time arguments in favour of the second view : — (ii). Is it cytoplasmic ? On this view it is a pathological clumping or agglutination of the lipoid katabolic basoplasm.s^ while polychromasia is a diffuse solution of lipoid matter. Accord- ing to Schillingse and Askanazy the latter may turn into punctate basophilia, while according to P. Schmidt and H. C. Rosss? the reverse process takes place. Hertzes believes the two things to be identical, because the number of basophUe cells in the blood of dogs poisoned with toluylenediamine is the same as that of polychromatic cells [ascertained by making counts on films stained {a) vitally, (&) after fixation]. The following facts may be noted : (i) Basophile granules may be abundant in a red cell, and yet the nucleus be absolutely intact ; *' (2) The staining reactions are : non-staining with methyl-green, blue* instead of azur-red with Nocht's method (difference from staining reaction of Jolly nuclear rest) , non-staining with the f uchsin in Pappenheim's methylene-blue fuchsin, whereas parachromatin should stain red by this method ; they do not accord with the staining reactions of basiplastin, paraplasm, or basophile parachromatin, but with those of spongioplastin ; (3) There are no transition forms between them and the Jolly bodies, although both structures may appear within the same cell ; (4) They are not associated with karyorrhectic fragmentation of the nuclei ; (5) In plumbism, the granules are excessively numerous, but pycnotic or other normoblasts are extremely rare. Ferrata's assertion that the edges of the nuclei are eroded in the vicinity of the granules is explained away as a misconception for perinuclear polychromatophilia (Grawitz) ; (6) They may appear in nucleated reds, but the nuclei are intact ; (7) Nuclear matter is opaque to ultra-violet rays, but the basophile granules are transparent (Grawitz and Gruneberg) f ; (8) These granules are seen in the bone-marrow even in cases in which the circulating cells show marked basophilia (Grawitz). This applies both to human cases and to experimental animals. (Naegeli explains this away by averring that they disappear from the bone-marrow during the agony !) (g) They may appear in entirely orthochromatic erythrocytes in which there is no nuclear matter at all. The sequence of development of the red cell would thus be expressed as follows : — * Maximow stated that some granules stain red with this method, but he was confusing a Jolly body with a basophile granule. t With dark-ground illumination the granules appear as clear spaces, differing only slightly from hasmoglobin in their refractive index (Saar, Dietrich'""). Life History of the Red Blood-corpuscle 81 Normal Process. 1. Yoimg nucleus = senile nucleus = (pathological intermediate stage or Jolly body) = chromatolysis. 2. Young cell-body = orthochromasia. Pathological Process* 1. Young nucleus = multiple nuclear fragments =karyor-rhexis. 2. Yoirng polychromatic cell-body = finely pimctate baso- philia = coarse punctate basophilia = plasmorrhexis = orthochro- masia (after complete loss of spongioplasm). The pathological series of changes would be explicable as the result of lipol5rtic toxins or ferments acting on the red-cell envelope.*'' As soon as the intoxication ceases, the normal process of maturation, would take place, unless an aplastic condition were set up. In either case the basophilia would feul to appear. The inference to be drawn is that if the clinician finds basophilic cells he will be aware that some toxic process is actually in progress. Evidence of regeneration or destruction of red cells in such a case is entirely another matter ; the basophilia merely implies inhibition or delay in manufacture of red cells. From these considerations it will be evident that the active discussion which has taken place among many hsematologists as to whether pimctate basophilia is or is not degenerative or regenerative in nature, requires no special consideration, because no one can well define what is the essential difference between the two series [of processes. If it be settled that basophilia is not a stage of normal maturation, but appears temporarily under certain ansemizing con- ditions, the practical man has sufficient information to guide him. Comparison between Vital Stainable Substance and Basophilia. VlTAL-STAINABLE Substance. Punctate Basophilia Occurrence in normal blood Occasional No Traumatic anaemia . . Yes . . No In chlorosis Yes . . Yes Cytoplasmic constituent concerned . . Lipoid Albuminous Association with polychromatophilia Yes .. Sometimes * Evidently there is no point in descaribing this as " embryonizatiou." 82 Biology of the Blood-cells The Heinz Bodies. — Like the reticular substance, these bodies stain with the vital stains, thiazin red, Nile blue, etc. Ery- throcytes containing these bodies do not show any trace of them by the dark-ground iUumination method until they have been stained by the pre-agonal method of brilliant cresyl blue or azur i. They then appear as brilliant phosphorescent points in the black field of each disc (Cesare Biondiei). Pappenheim regards them as composed of cholesterin-olein, because in phenyl-hydrazin poisoning (where they are abundant) the blood contains more cholesterin,»2 and the red cells are resistant to saponin. ^3 Heinz himself regarded them as dead cytoplasm, the result of partial necrosis of the erythrocyte.^* Hartwichs*^ found that these bodies contain protein (probably metalbumin or pure nuclein), a body allied to histone (readily soluble in acetic acid), a lipoid body devoid of cholesterin but containing free fatty acids, and some form of hsemo- globinic iron. Schwalbe and Solley's theory^s that they are nucleoids, and become blood-platelets after being cast off, is excluded because they contain haemoglobin and are therefore more likely to appear as microcytes. In other words, these bodies are not the same as JoUy bodies, but are identical with the intraglobular bodies* of hasmoglobinaemic blood (pol)nneiized heemoglobin of Ehrlich), just as are the schizocytes seen in the blood in phenyl- hydrazin poisoning. Although these bodies are hyperchromic, they do not necessarily imply that the corpuscles are diffusely hyperchromic (from conversion of Hb into methsemoglobin). They only develop in vivo.^^ Red Cell Shadows. — A small number of shadow-forms occur in the normal circulating blood.^^ They present a double contour which stains reddish-blue with Giemsa, while the central portion is coloured pale lilac. They are said to give rise to irregular elongated bodies, when exposed to physical influences. Similar forms occur in pathological blood. They are demonstrable by dark-ground illumination.ss * So-called " Innenkorper," seen within the erythrocyte with the ultramicroscope, and showing molecular movement. They are not artefacts, or secondary pathologicsil granular change in the polychromatic erythrocytes, or nipping off of the lipoid basophile substrata of the discoplasm. Life History of the Red Blood-corpuscle 83 Nature. — They are washed-out red cells, and can be produced artificially. Significance. — The presence of such bodies in circulating blood indicates that red-cell destruction goes on in the blood-stream, and not exclusively in such organs as the spleen. Nuclear Relics within Erythrocytes. — The Howell- JoLLY Bodies. — These are seen as excentric round structures as large as a nucleolus, within the red cells under certain conditions.* They stain with methyl green, which indicates their nuclear nature and distinction from basophilic granules. A mixture of methyl green and azur dyes stains the centre of the " rest " red, while the periphery is punctate. They consist of a mixture of prochromatin and metachromatin, and constitute an intermediate stage of chroma- tinolysis of the nucleus — a transition between the pycnotic form of nucleus and final stage of complete loss of nucleus. Occurrence. — They may be readily demonstrated in cats after venesection or poisoning in the embryo (Pol, Schmidt, Jolly), and in human blood in cases of pernicious anaemia (Morris). They may be associated with basophilia. The Cabot Ring Bodies^^ are seen as rings or loops within (polychromatophilicioo) red cells. They stain with chromatin dyes, especially with Giemsa. Occasionally they present altogether an irregular shape. Occurrence. — In plumbism, in severe ancemias,ioi in anaemia pseudo-leukaemia infantum,io2 but not in embryonic bloodf or adult bone-marrow or any physiological condition. Nature. — These bodies are regarded as the peripheral part of the erythroblast nucleus (nuclear membrane), because transition forms can be seen in which the nucleus is partly vacuolated in the centre, while the periphery is intact.ios It may be noted that these rings may occur in basophilic red cells, and the difference of staining reaction (the ring azuroplule, the granules basophUe) is then sufficient to show that the granules are not derived from the nucleus.io* It is possible that these ring bodies are the * First described in cat blood by Howell in 1890. t Guinea-pig, rabbit, mouse, dog, cat. 84 Biology of the Blood-cells result of accelerated karyolysis in cases of hyperactive re- generation. Chromolinin Granules. — Granules like fragments of nuclei have been described as circulating in the blood ;io5 they have been regarded as chromolinin granules. The various granulaj structures which can be seen within red blood-cells may be reviewed in the following tabular form, for the purpose of aiding the clinical pathologist : — Visible in l4 Occur in Methyl- green- Giemsa Hsemat- 1 .5 a T3 Q. •si a is c 8" |.He Pyronin oxylin la ss True basophile punctation : (a) fine . . Cytes and Hardly blasts + + Red Blue visible o + (6) coarse Blasts o -f Intense Intense o o Partly Nuclear rests (in granular erythroblasts) Blasts + Green Red -f- + o Multiple fine acid granules* Embryonic o + o o o o Substantia granulo-fila- mentosa (al- kaline granu- Normal lation)! cytes o + o o o o -1- Substantia metachro- matico-gran- ulosaj Cytes o + o o o + o Maurer-ScMff- ner puncta- Malarial tion cytes o -1- o o o o -f * stained by vital stains : occurring in embryonic erythroblasts ; coloured bright carmine with neutral red.i»' Giglio-Tos"« thought these were degeneration-products of haemoglobm. Pappenheim"' considered them analogous to the keratohyalin granules of epidermal cells : a portion of the cytoplasm which is subsequently lost as the blood-discs, become mature. t Stain red, brown, or blue with neutral red thionin, or cresyl blue. J Solitary, coarse. Life History of the Red Blood-corpuscle 85 The Blood-Platelets.— The most easily observed pheno- menon associated with the death of a red blood-cell is that of platelet formation — an agonic process occurring in a certain per- centage of the erythrocytes. It need not be supposed that every platelet comes from a red cell, as will be shown below. The blood-platelets vary much in form, some being roxmded and some flagellate. The latter simulate hsemozoa.ios Their exact shape depends considerably on the method of fixation employed for their demonstration. All stages between weU-defined nucleolar bodies with a delicate cytoplasm, and nucleiform structures con- taining azurophile granules, can be seen. The number of platelets is variously given at 200,000 to 778,000 per c.mm. They are less numerous in the child."" Reid*^" gives the average figure for the adult at 300,000. At birth, according to Morse.^ the figures vary between 350,000 and 400,000.* Characters. — Size : 1-5 p.. There is a protoplasmic zone, enclos- ing a chromatic body (" chromidium ") staining with azur dyes. With osmic acid fixation, and vital staining, a capsule-body can be demonstrated, according to Schilling. Centrioles can be detected within the capsule-body {see p. 70). Filamentous inter-connections to red cells can also be demonstrated. A guess has been made that such filaments are the same as the so-called haemokonia. Spodaraii^a asserted that he had seen atj^ical karyokinetic figures within blood-platelets, but it is more than likely that this is erroneous. Chemical Characters. — Gross analysis shows platelets to be made of nucleo-proteins, lecithin, and cholesterin. Prothrombin is also assumed to be present in them (Schafer^T), and subsequently interacts with lime salts in the plasma to form the fibrin-ferment. Iodine shows the presence of a few glycogen granules. Nile blue sulphate, osmic acid, and Scharlach R do not stain them, and they contain no true nuclear material. Sapegno found that Winkler- Schultze granules are present.^^ Attributes. — The platelet was fotmd to be amoeboid by Deetjen."7 Their ready explosion into processes which adhere to •other observers are Pratt, Wright, Muir, Affanassiew, Kemp.""-''' 86 Biology of the Blood-cells adjacent objects would enable them to plug torn vessels and stop haemorrhage. White thrombi are made of platelets (Bizzozero.ns Eberth, and Schimmelbusch, 1888). Schafer points out their analogy to the large cells in the perivisceral fluid of echinoderms.iw According to Eminet.'^" the platelets present different and specific dye-affinities in different infectious diseases. Thus, the platelets in a case of diphtheria are different from those in a case of tuberculosis or scarlet fever. In other words, an infective agent can influence the composition of the reactive cells, and the soterocytes, as he calls them, are the manifesta- tion of the specific anti-bodies. Diphtheritic serum, on this view, would be composed of specific diphtheritic soterocyte.* Aynaud'^^^ also considers that the platelets play an important part in the production of alexin and antibodies. Brockbanki22 suggests that the blood-platelet material is a regeneration-product, and represents " potential haemoglobin " — some protein constituent ready to enter into the production of haemoglobin. This would explain why platelets so easily form in secondary anaemias, where re- generating power is good, and so rarely in primary pernicious anaemias, where the corpuscles themselves are damaged. The following are the theories as to the origin of the platelets": I. That they are derived from red cells.f Evidence : (a) They are more abundant the longer time is allowed to elapse after drawing the blood. I (b) Very many of these bodies can be found lying close to the " mouths " of eviscerated red cells, or even within the red cell itselfi22 (Fig. 26). The red cell loses no hemoglobin in the Fig. 26. — Platelets escapentg from Red . BLOOD-coRPUsctES (after Brockbank). * If the platelets be not preformed, this theory falls to the ground. n t Hirschfeld,!" Preisich and Helm, i ^ ' Roscoe King.i" If they come from the red ceU, they may be centrosomes or ceutrioles (Eisen"«) or fragments of nuclei from the bone- marrow erythroblasts (DantschakofP"), or globulin-droplets from the cell-body or nucleoids. ^ ' tin this connection the above remarks, relating to the paucity of platelets in primary anamia,»» and their extreme abund^ce m secondary"' and post-hamorrhagio an£mia,i» may be noted. Mary Morse"' found no relation between amount of menstrual aow and platelet content (platelets mcreased before onset). Life History of the Red Blood-corpuscle 87 process, and may part with several platelets, (c) If blood be collected directly into the gap between two closely applied cover- slips, which are then separated in the usual way, very few platelets are found (showing that contact with air is requisite for their appearance, and not contact with glass), (d) In those animals whose red cells are nucleated, platelets do not occur. The reason why platelets cannot be seen within ordinary red cells may be that the haemoglobin obscures their staining property, and that special fixation might be required. Such evidence as that which has been presented should suffice to show that the bulk of platelets is derived from the interior of normal red cells. This view is shared by Pappenheim, Hirschfeld, Schilling,i3 4 Maximow, Engel, Preisich, Weidenreich.iso Perhaps the only difficulty lies in settling whether the material of which they are composed is, or ever was, nuclear matter. The other theories are unimportant : 2. That they are derived from breaking-down leucocytes (Decastello and Krjukoff, igii). Against this view is the everyday finding that platelets are extremely seldom anywhere near a leucocyte in the film preparation. Leucocjrtes occur in vertebrates below mammals, but platelets do not. On the other hand, the frequent finding of lymphocytes, for instance, in which constricted budding plasmoschistic fragments become detached, suggests that some platelets may come from this source. 3. That they are derived from megakaryocytes (Wright, Bunting).'" This view implies that the platelets arise in the bone-marrow. If that were so, we should expect (a) that megakaryocytes would be excessively numerous, considering that hundreds of millions of platelets occur per c.mm. (to accept the current ideas as to the content of platelets per c.mm. of circulating blood) ; (6) That the numbers of platelets are constant. The objections to the view, even though it is accepted by Sternberg*^' and Schridde, seem to be incontro- vertible, namely, they are not present in absolutely fresh preparations, or in every preparation ; they are more abundant in blood-films made at the end of the operation than at the moment of the prick. This has been a frequent experience in the writer's hands, and is also emphasized by Brockbank,'" who carried out counts at successive intervals. The evidence for the view consists in an observation that megakaryocyte pseudopodia have been found in the films (how identified as certainly megakaryocyte ?) and that platelets are absent in animals whose marrow shows no megakaryocytes. Re last statement, what of the platelets in Crustacea, who have no bone-marrow ? 4. That they are really separate cells (specific cells). In favour of this view is the fact that they appear in large numbers without any evidence of destructive change in either reds or whites during clotting ; that there is no 88 Biology of the Blood-cells numerical relation between platelets and reds or whites.* The following experiment has also been advocated as evidence : FUl a syringe with lo per cent sodium citrate, and take up 9 c.c. blood from a vein into it. Expel the whole into a paraffined test-tube, and put on ice for an hour. The surface layer will then be found full of platelets, f 5. That they are simply a chemical -precipitate from the plasma.J Buck- master"2 jjas gone thoroughly into this aspect of the subject, and concludes that platelets are artefacts. He divides them into: (a) Those containing hemoglobin ; (6) Those without hemoglobin ; (c) Those with an inner- body ; (cf) Those without an inner body. 6. That they are analogous to the thrombocytes of lower animals ; because both are related to coagulation of the blood, and Romanowsky staining shows a nucleiform structure in each. The objection to the analogy is that the central azurophile granulation is not true nuclear matter. ^^ 7. Hayem's original doctrine has been finally controverted.''' He believed that the lymphocyte or leucocyte of the blood-stream gave rise to the hsematoblast or platelet, was then cast out into the blood-stream, and then " grew " into a red cell. The basis of this view lay in observations on pigeons (Luzet), but similar pictures have not been found in man by the majority of observers ; and was supported by the fact that the blood-platelets are_increased in regenerating blood. As regards the histiogenesis of the platelets, this has been variously placed in the bone- marrow, spleen, liver, and lymph- nodes. II The Demi-lune Bodies. § — These vary in size up to 350 microns. They are circular bodies ^. , . _„^ „ „„„^ , „„ of extreme transparency save for Fig. 27. — ^A Demi-ltjne Body (after ^ -^ ffS-bol;';1rc^'triS;^°\T'N?^ai a sickle-shaped structure stained erythrocyte for comparison Of size. ^-^j^ hsmOglobiu. The CreSCCUt is punctated. The whole body resembles the appearance of the " old moon between the horns of the new moon " (Fig. 27). It is met with in malarial blood, in convalescents from typhoid (Schillingi^*)^ and has been noted * But it is impossible to count platelets accurately. t The fallacy is^that the whole manipulation, including the drop of temperature, provides just the most favourable circumstances for the production of platelets. X E.g.,t globulins (Lowit, Wooldridge). II A good historical review of this subiect is given by Werzberg, Fol. haem. 1907, Bd. X., i., p. 301. First noted by Sergent ;^'' later by Brumpt.'^' o Life History of the Red Blood-corpuscle 89 by Langeron in the blood of rats and guinea-pigs, especially if they be rachitic or kept in lead cages. Schilling produced this appearance in red cells by incubating blood. The phenomenon may be looked on as an indication of imbibition in a degenerated erythrocyte whose outer layers have become " pachydermatous " from anaemia and inspissation of the serum. Changes in the Haemoglobin' Content. Hyperchromia. — This term indicates that there is an increase of haemoglobin in each red cell. It is the result of a chemical change in the haemoglobin, and is associated with a lipolytic change in the stroma of the red cell. The latter explains the extreme flexibility of the cell, and the occur- rence of dumb-bell forms. Hyperchromic schizocytes are produced by union of the altered haemoglobin with the lipoid of the plasma. This phenomenon is of considerable interest in connection with the study of pernicious anaemia. In that disease, as is weU known, the colour-index is increased — that is, each red cell is assumed to contain more haemoglobin than is normal. The following experi- ment, devised by Pappenheim, indicates the fallacy of this con- clusion. Into each of two test-tubes are placed 2 c.c. of a washed emulsion of sheep red cells. To tube A is added a drop of saline, and to tube B is added a drop of water containing a crystal of hydroxylamine. After shaking a short time, tube B turns brown. If each solution be now tested with Sahli's haemoglobinometer it wiU be found that the unaltered red cells contain 23 per cent Hb, and the other tube contains 46 to 50 per cent. It is evident that the Sahli reading gives a false idea of the state of the blood, because all that has happened has been to convert the haemo- globin into a met-haemoglobin compound. The conclusion is, that in pernicious anaemia the toxic agent has altered the original haemoglobin, and converted it into a pro- met-haemoglobin or met-haemoglobinogen (Pappenheim), just as haemolytic agents, animal haemotoxins, and certain bacterial poisons may act on the haemoglobin chemically.* If this conception of the change be correct, it is evident that any discussion as to * Schultze explains hyperchromia on colloid chemical principles. External agents acting on the lecithin stroma alter the fixity with which the oxygen is held in by the haemoglobin lecithin jelly. 90 Biology of the Blood-cells whether hyperchromia is degenerative or regenerative is futile. It may be noted at this point that hyperchromia is often associated with macrocytosis (see opposite). Hyperchromic red cells occur as either megaloblasts, or normocytes, or degenerate swollen macrocytes. It will be seen that the normal blood contains some cells which are usually spoken of as diseased. An analogy can be drawn to the familiar problem of the difference between arterial and venous blood — where the altered colour of the blood is due not to an excess of CO3 but to a relatively greater proportion of COj to O. Normal blood contains a larger percentage of " normocytes " than anaemic blood. Consequently, the best conception of the changes met with in the ansemias is to group them according as the abnormal cells are more and more abundant. A cancerous anaemia is thus 98 per cent simple anaemia + 2 per cent hyperchromic anaemia. Progressive pernicious anaemia is 98 per cent hyperchromic anaemia and 2 per cent simple anaemia. Such conditions as syphilitic anaemia, leukanaemia, malarial anaemia, Banti anemia, are then intermediate forms showing varying proportions of h5rperchromatism of the red cells. Every individual is anaemic in the strict sense of the word, but every healthy individual does not have more than I per cent microcytes (see opposite). Here, again, emphasis is laid on ideas which go to show the futility of attempting a dia- gnosis of anaemia on the presence of one megaloblast for instance. As wiU be shown presently, our study of the blood-film is made with the object of finding what is going on in the formative tissues, or of detecting the existence of some type of toxin (be it — NHj, or — NH, or — CN, or CIO3, or — NOH, etc.) actually circulating in the blood- stream. By searching for diagnostic indications on this plan the physician will never ask himself : Is this pernicious anaemia, is this chlorosis ? but — Is there such and such a group in the circula- tion ? Is there such and such a failure on the part of the bone- marrow to form red cells ? Is there such and such an aUomorphic change in the red-cell (chemical) components ? The condition of hyperchromia need not be considered any further. A defect of haemoglobin in a red cell is more easy to explain than an excess of the same substance. As we have seen, the Life History of the Red Blood-corpuscle 91 probabilities are that there is no such thing as an " excess of hsemo- globin " in one individual cell. Alterations of Shape of the Red Cell.— PoiKiLOCYTOSis is SO familiar a phenomenon that little need be said about it. There are the following possible explanations of the production of poikilocytes : (i) Physical or osmotic changes in the serum may lead to distortion of form of the red cells. This is the only likely explanation. Some authorities have stated that it is evidence of amceboid movement ; others (2) That it is an artificial production ; others (3) That poikilocytes are fragments of red cells (Ehrlich) and serve the purpose of increasing the avail- able haemoglobin surface in the circulation ; and others (4) That a poikilocyte is a hastily-formed red cell. Elongated sickle-shaped red cells were noted by Washburn in the blood of a negress suffering from an obscure ansemia. Alterations of Size of the Red Cell.— MiCROCYTES are unduly small red cells (3 to 5 ^) ; they are round, have a deep dimple, and only differ from ordinary red cells or normocytes in their dimensions. Some authorities consider them to be immature, others believe them to be breaking down. Biemacki suggested that the normocyte contains a certain amount of plasma, and becomes a microcyte by giving up this plasma to the blood-fluid in the course of natural processes. Litten regarded them as osmotic effects, but their regular contour is against such a view. Another view was that they are buds of ordinary erythrocytes. Macrocytes* are unduly large red cells (7 to 20 ft), and resemble the normocyte in other respects. They are, however, very pale, and the dimple is very shallow, if present at all. The ordinary macrocyte is really an absolutely spherical body (Plehn). The cell stains less strongly with eosin. Whereas some observers regard these cells as megaloblasts which have lost their nucleus too soon, others look upon them as being purely osmotic effects. The question as to whether they are to be looked upon as degener- ative or not is superfluous, because mere reaction to physical influences is entirely another process than " degeneration." * Very large cells (more than 20 h-) are called gigantocytes. 92 Biology of the Blood-cells The view propounded by some authorities that the macrocyte is characteristic of pernicious anaemia is disproved by the detection of such cells in simple secondary anaemias. Meyer and Naegeli believed that they had detected a new sign of pernicious anaemia in the occurrence of hyperchromic macrocytes (increase of colour index). This is disproved by observations on experimentally produced erythrocyte destruction (met-haemoglobin-forming poisons) and the lessons learnt therefrom (Pappenheim). Anisocytosis is a term denoting that there are cells of a number of sizes circulating in the stream at once. They may still be classified into microcytes, macrocytes, and normocytes. This term refers to an exaggeration of variations in size, since it must be remembered that in perfectly normal blood the corpuscles are not all of the same size. Thus the proportions of cell-forms in the order just named would be i : 33 : 66 in normal blood, and 17 : 51 : 32 in pernicious blood (Schaumann). The Comparative Morphology of the Red Cell. — ^The fact that the red cells of animals vary considerably both in shape and size has long been known. The elliptical forms are commoner in the cold-blooded animals and in birds, the round forms in the mammals. The former types possess a thicker envelope than do the latter, and fibrils are described^" as running round the peripheral part of the red cell. The elUptical forms are biconvex, the promi- nence being due to the presence of a nucleus.^** The blood of invertebrates does not contain red blood-cells, as a rule. The plasma contains the pigment. Haemoglobin is present in the worms and lower Crustacea, but in echinoderms the pigment is different, being called echinochrom (red). Some worms contain chlorocruorin (green). The blood of molluscs and higher Crustacea contains hasmocyanin (blue), in which copper is present instead of iron. It has three times as little power of binding oxygen as has haemoglobin. Venous blood is colourless in such animals. Colourless oxygen-binding bodies called achroglobins occur in the blood of some molluscs and tunicates. The knowledge concerning the red cells in animals below the birds is chiefly derived from the researches of Werzberg,^*^ who gathered together all the information obtainable in the Uterature up to 191 1. It will suffice to sketch out the broad outlines of the subject. The cells to be considered fall into three groups : the orthochromatic cells, the polychromatic cells, and the megaloblasts. The haemoblasts have been variously named by various writers, and are difficult to trace in terms of modem haematology. However, the ancestor of the haemoblast appears to be a lymphoidocytar cell, having characters such as were referred to in the preceding chapter. Life History of the Red Blood-corpuscle 93 The red cells of the Fish are sometimes almost quite round (cyclostomes), sometimes oval, and the nucleus varies in shape from a rod to the ordinary oval form. In some instances the nucleus is round (tinea, leuciscus rutilus, esox lucius, and gadus lotus), and shows varying structure, sometimes clearly defined, at others obscure. In some cases, pycnotic forms of normoblast may be observed (carassius, cobitis fossilis, perca fluviatihs) . Polychromatic normo- blasts are usually scanty in the circulating blood, but in esox they are numerous, the nucleus is large, and the cell may be larger than the normocyte. Megaloblasts are sometimes abundant (roach, minnow, and cod), and in some cases, notably the perch, they are seldom seen. Platelets are absent (Fry"6*). In the torpedo,^" the adult blood, like that of the embryo, contains granulo-filamentous red ceUs, orthochromatic oval macrocytes rich in haemo- globin, polychromatic macrocytes, ortho- and poly-chromatic microcytes, occasional cells with karyoMnetic figures, and lymphocytoid haematogonia. The latter are round, with a large vesicular nucleus, and faintly basophile cytoplasm. As the haemoglobin appears, the tint becomes more violet (with panoptic stain). Thrombocytes are present. In this fish the red cells appear in smaU numbers, but their large size compensates for their paucity ; they are at least five times as large as in man. The haemoglobin-content is 21 to 22 per cent with the Fleischl instrument. In scyllium, the red cells include : (1) Round bodies with round nucleus (embryonic cells) ; (2) Oval cells with oval nucleus (derived from bone- marrow) ; (3) Transitional forms to megaloblasts ; (4) Normoblasts. There are no spindle cells. The fact that red-cell formation is locaUzed to the bone- marrow, and that juvenile cells are abundant in the blood-stream along with mitosing forms, has been explained on purely physical grounds by Blumen- thal.*^ He points out that the osmotic pressure within the animal is the same as that of the medium in which it lives, and prevents the ordinary processes of cell-division, such as we are familiar with in the mammals. The normal red cell of the cyclostome petromyzon is vesicular, and con- tains granules of haemoglobin ; it is irregularly round, variable in size, and the nucleus is a little longer than broad. Pycnotic forms occur, as well as some forms without nuclei at all — true erythrocytes. There are no polychromatic red cells, and no megaloblasts are to be found. The blood of many Amphibia contains red ceUs which are visible to the naked eye, but their numbers are much smaller than in other animals. They also include megaloblasts and normocytes, the former giving rise to the latter, although a certain number of normoc5rtes arise from polychromatic normoblasts which are derived from metaplasticaUy transformed primordial cells. The megaloblasts have a relatively large central round ambly- chromatic nucleus, which, in the unstained state, is strongly refractUe. The normocytes occur in two forms : (i) With large round amblychromatic nucleus and polychromatic cell-body ;* (2) A blood-mature cell with normo- blast type of nucleus, and of large size. This is a large normocyte. A variant of this is the microcyte. * The erythroblast of some authors. The microblast is a variant. 94 Biology of the Blood-cells The sequence of development is : lymphocyte = cell with more proto- plasm, and basophile flakes ; nucleus larger, round, and clearly defined structure = cell with oval nucleus and commencing hasmoglobin deposit = finished red cell (Freidsohn^'^). The blood of the jrog* contains seven varieties of red cell ; there is : (i) The medium-sized, oval, orthochromatic form, whose cytoplasm is orange, whose nucleus is blue and irregular in contour (oval in the young animal) and contains a dense but distinct net-work. Some of these have pycnotic nuclei, others have none at all (Pappenheim, Engel). (2) Poly- chromatic normoblasts ; these are of medium size, oval shape, and have a relatively large nucleus. They contain little hasmoglobin. Such forms are more numerous the younger the animal. (3) All kinds of transition forms between (i) and (2). (4) A few orthochromatic megaloblasts, with large round oxyphile cell-body and large round nucleus. (5) Microcytes (ortho- chromatic, with relatively large nucleus). (6) Polychromatic microblasts. (7) Cells showing punctate basophilia. It is of interest to note the seasonal periodicity of activity of red-cell formation in the frog. This is marked between May and July. In bombinator, the megaloblasts are very numerous, while polychromatic normoblasts are scarce. The erythroblasts are round, flat discs with large nucleus and only a rim of cytoplasm. They are polychromatic. Dimictylus viridescens has very large red cells, which include many megaloblasts, but very few polychromatic normoblasts. AU amphibian red cells have a characteristic nuclear structure, since the network forms broad feet which rest on the nuclear membrane all round. The blood of axolofl^" contains 300,000 red cells per c.mm., and 23 per cent hsemoglobin. The red cells show well-marked reticular substance, are of ovoid shape, and appear in two forms : the lymphocytoid, and the ortho- chromatic. Mitotic figures are occasionally observed. The erythroblast is round, basophile, and bears a peripheral zone of hemoglobin. Some are polychromatic. The nucleus is round and relatively large ; the chromatin is spongy and contains a substance stainable with methyl green, arranged in radial fashion ; a pyroninophile substance occupies the remainder of the nucleus, with the addition of two round nucleoli, which are surrounded by a clear halo. The smaller the nucleus becomes, the nearer are the nucleoli to the surface ; they finally become expelled into the cytoplasm and appear as the granules of the reticular substance (Sabrazes). The red cells of the Reptiles are always oval, biconvex, and nucleate. They are smaller than in the amphibia. They comprise three main groups : the orthochromatic forms, the polychromatic forms, and the megaloblasts. The latter may show mitotic figures, and at times are very Uke lymphoido- cytes. The orthochromatic ceUs are large, oval, and hyaline in aspect. The nucleus is variable in size, and the nuclear network does not touch the nuclear membrane in the same manner as was described for the frog, tut the thick feet are replaced by slender, pointed processes of chromatin. Bufo, and all kinds of frog, also salamander and proteus. Life History of the Red Blood-corpuscle 95 The haemoglobin is at the edges and at the poles of the cell. Some of the orthochromatic cells are small, and are called microcytes ; some of the others show a pycnotic nucleus. The polychromatic cells occur in two forms : (i) Large oval bodies whose cjrtoplasm appears flocculent, and surrounds a nucleus with well- marked nuclear nelrwork ; (2) Very small forms, very similar to the spindle cells. There are many transition forms between these two main groups. The megaloblasts are few in number, large in size, oval in shape, and orthochromatic in tint. The nuclear structure is blurred. The differences observed in the different reptiles consist in the form of the nucleus, and in the relative proportions between the cell tjrpes mentioned. Thus, megaloblasts are few in tropidonotus, testudo, anolis, scincus, agama, hemidactylus, chalcides, and moderate in number in anguis, emys, lacerta. In no case are they abundant. The polychromatic forms are absent in tropidonotus, and very numerous in testudo, platydactylus, and chameleon. In testudo, the following forms of polychromatic cell have been described : (a) Medium-sized, round cells with large round nucleus, and rim of cyto- plasm ; (6) Similar forms with an oval nucleus which almost fills the cell ; (c) Similar ceUs with round nucleus, feebly basophUe cell-body, oval in shape ; (d) Small polychromatic elongated cells with a large long nucleus ; (e) Very small and narrow cells, poor in haemoglobin, but not at all basophile. Large and small forms of polychromatic cell appear to be noted in all those cases in which any are to be found at all. Transitional forms are then also present, and the largest examples may appear like megaloblasts (megalo- blastoid cells in lacerta). Microblasts are noted in platydactylus, emys, and chameleon. Lymphoid haemoblasts have been described as occurring in platydactylus ^Werzberg), and similar cells — ^large, round, strongly basophile — were found by the same writer in lacerta. As regards the normocytes, rod-shaped nuclei are present in tropidonotus, lacerta, algeroides, anolis, platydactylus, and in some chameleon red cells. Pycnosis is not often seen, but irregular nuclear forms have been des- cribed in testudo and lacerta. Microcytes are noted in some of the reptiles. In the tortoise, red-cell formation is active in spring, but very slow in winter. The erythrocyte develops from the lymphoidocyte of the bone-marrow by accumulation of haemoglobin, as well as by mitosis of the circulating erythro- blast (Eberhart"»). In the Birds, the red cells are larger than in mammals, and are relatively more numerous. Similar forms of red cells are to be found, as have been described in the preceding groups. There are flat elUptical biconvex discs with peripheral haemoglobin, and small round, or sometimes ovoid, nucleus, in which structure is rather indistinct. There are small orthochromatic forms, or microc5rtes, with more clearly defined nuclear structure, since the chromatin strands are thick and impinge on the membrane with foot-like bases. Cells with pycnotic nuclei can be observed, which are otherwise like the ordinary erythrocyte, and contain much haemoglobin. Lastly, megalo- blastoid cells occur with basophile or polychromatic cell body, and relatively large ovoid nucleus in which the chromatin masses are larger and more 96 Biology of the Blood-cells clearly defined than in the preceding forms. Ljmiphoid hsemoblasts may be detected in which the cell-body is narrow and deeply basophile, and all transitions between these and the polychromatic megaloblasts can be made out. These varieties apply to the blood of the domestic fowl. The cells in the pigeon are similar in form. The cell types in other birds have yet to be studied carefully by modem methods.* In general, the larger the bird, the larger the red cell. Mammalian blood, with the exception of that of the camel, is charac- terized by the fact that the red cells are strictly round discs, and are non- nucleate. The following list of the comparative sizes (in microns) of the red cells in various animals may prove of interest : — Torpedo . . 20 x 88 or lessf Axolotl . . . . 27 X 84! Proteus anguineus 62-5 x 34-5 Newt . . . . i9'5 X 29-3 Amphiuma tridactylum 45 x 83 Frog . . 14-5 X 25 Pigeon . . . . 8-5 X 14-5 Finch . . . . 3'6 Napu deer . . 2 Goat Llama Sheep Horse, Ape, Rabbit, Cat, . . Dog Man Elephant Camel 4 4x7 5 6 7 7-5 9 13 The red cell content of the blood of various animals (cells per c.mm.) : — Proteus . . . . 36,000 Sheep . . 14 mill. Frog . . . . J miU. Goat . . 10 „ Fish . . . . J-J „ Man . . . . 5 „ Birds . . . . 1-4 ,, The Spindle Cell. — This form of cell, described by Reckling- hausen, in i866,i48 was first considered to be the analogue in birds of the blood-platelet in man. In point of fact, however, it occurs in aU vertebrates below the mammalia, with but few exceptions, and is regarded as a ceU-entity. These ceUs deserve mention because they appear as definite blood-cells in some animals, even though they play no part in human physiology. The spindle cell is a pear-shaped, or almond-shaped plaque, with a central protrusion on each surface, in the position of the nucleus. The cell is sometimes rounded at the poles, sometimes very obtuse. * The most recent works on erythrogenesis in birds are those of WenzlafP'" and Kasarinoff.i" t Sabrazes and Muratet."' Life History of the Red Blood-corpuscle 97 Size. — J— I X ir-k the diameter of a mature red cell. Cell-body. — ^Finely grantilar or fibrillated. The fibrils are concentric. Edge smooth. There is no haemoglobin present, no opacity, no optical structure, no granular appearance.* Occasion- ally some vacuoles are present. In tropidonotus and chameleon, Unna-Ziehl staining brings out a deep red rim to the cell. Centrosome. — Is in a dimple on one side of the nucleus. Polar centrioles are seen in testudo and birds in panoptic stain. Nucleus. — This is oval in shape and contains no coarse chro- matin fragments, but numerous grantiles of chromatin, which appear to lie in a lining network (Salamanderi^s). On the inner wall of the nucleus in triton is a sickle-shaped clear area. The chromatin reticulum is made up of delicate fibrils, and shows a longitudinal folding (mitochromes) of the nuclear membrane. Nucleolus. — 1-2. According to Werzberg, nucleoli are absent. Mitosis. — Some authorities have observed this (Mondino, Salaieo) ; others deny its occurrence (Meves and Werzberg). In birds, the spindle ceUs are long and have an elliptical nucleus. They are regarded by some as identical in function with the mammalian thrombocyte.^^o After being shed, they become spherical, and throw out processes and adhere to one another. Fibrin filaments are seen to exude from them subsequently. In other words, they subserve a very definite function at the very time that they are in articulo mortis. The observations made by Werzberg led him to conclude that the spindle ceU is not the parent of the erythrocyte, nor yet derived from the l3Tnphocyte (Neumann's view). While the spindle cell is endowed with the same functional powers as the platelet of the mammal, it is not morphologically related to the same ; rather does this cell give off fragments of material which correspond to the mammaUan platelet. The genealogy of the erythrocyte may be represented thus, following Pappenheim and Werzberg : ^'^^ 11 1 ~ lisemoblast = polychromatic nonnoblast = erythroc3rte. thrombocyte * Neumann found a few tiny colourless refractile granules, which Hayem believed to be myelin, Pappenheim lipoid. 98 Biology of the Blood-cells The theories as to the origin of the spmdle-cell are fully dealt with by Werzberg.**' It will suffice to poiat out that there are the following views : That they are derived from : (i) Leucocytes ; {2) EndotheUal cells ; (3) Red cells ; {4) Giant cells or megakaryocytes ; (5) That they are separate entities ; (6) That the red cells are the descendants. With reference to the fourth view, advanced by Wrighti'i and Rawitz,'^" it is of interest to note that the same argument is advanced as was employed to demonstrate that the platelets of man come from megakaryocytes. It has been noted by these observers that giant cells containing anything up to twenty nuclei are observed, which cells present amoeboid movement, and amount to agglomerated spindle cells. In other words, the lower animals, which have no megakaryocytes, have these agglomerations of spindle cells, and give rise in due course to free spindle cells whose function is identical with that of the mammalian platelet. The latter in its turn comes from a megakaryoc3rte. The objections to this view have already been mentioned. The theory, from the side of the spindle-cell, is referred to by Werzberg as a " curiosity."* The Hsemokonia, or Blood-dust-^^? — This material appears in various forms, which have been divided by Porteri^s into the follow- ing : (i) Flagellate bodies of indefinite shape ; (2) Large diplo- cocci capable of rapid movement ; (3) Bodies measuring 2 to 4 ft, showing similar movement, but possessing indefinite shape ; (4) Slightly round vesicular bodies with a central ruby-coloured spot, and only seldom mobile ; (5) Small micrococcal forms exhibit- ing active Brownian movement. These bodies are all strongly refractUe, and can be readily seen with the ultra-microscope (Reicher,i39 Rosenthal^^o). They can be stained with vital-staining dyes of the ammonium series (Pappenheunwi). It is difficult to decide upon the nature of these particles. Since they give fat reactions (sudan stain, solubility in ether), it has been supposed by Muhlmann that they are fat. They are found to be more numerous after a meal rich in fat. Thus, after a large quantity of butter has been ingested, an ultraraicroscopic examin- ation of the blood is ascertainable, according to Neumann,i42 and is useful for comparing health with cases of pyloric obstruction. These observations are contested by Wiener.i^s who believes that haemokonia are inconstant, and are insoluble in ether. Cottini62 * other references on spindle cells are quoted in the literature under numbers 153, 157. For illustrations, see Plate II. Life History of the Red Blood-corpuscle 99 found them more abundant in the vessels leaving the intestine than elsewhere. It has also been supposed that blood-dust is (a) the result of breakdown of red cells ;* (b) derived from proteins or lipoproteins in the leucocytes. Haeraokonia are less numerous in the newly-born ; they are increased after radium-therapy (Cottin). They have no relation to the coagulation of the blood. ♦ Porter^'' comes to the same conclusion from his observations. It is difficult to be sure that extraneous matter and post-mortem autolytio changes have not been mistaken for these bodies. 100 Biology of the Blood-cells IV.— THE METAPLASTIC, METAHYPERPLASTIC. AND APLASTIC PHENOMENA OF ERYTHROPOIESIS. Brief discussion of the nature of ansemia — A classification of anaemias — Relation between the facts detailed in the preceding sections and clinical work — Poly- cjrthsemia. The pathological changes which occur in the fonnative centres for red cells lead to the appearance of anaemia or poly- cythsemia if the erythroblastic line of development be affected. Some of these changes belong to the class of " plasias," and it is by studying them that better conceptions of the nature of anaemias can be obtained. The ordinary blood-count is of relatively small value in elucidating the pathology of a case of anaemia. The empirical use of such a count leads to unsatisfactory results, as it tends to the erroneous belief that a certain number of reds per c.mm., a certain percentage of haemoglobin, and a certain number of leucocjrtes per c.mm. will definitely decide the nature of the anaemia and the line of treatment to be followed. We would emphasize that the morphological characters of the blood-cells themselves are of vastly greater importance than the mere determination of total numbers of red cells, etc., with anything more than approximate accuracy.* There is no such thing as a primary anaemia. Every anaemia is the effect of agents either on the circulating blood or on the bone- marrow, or on both at the same time. The agent is often of unknown nature, and, indeed is sometimes apparently of the nature of a filterable virus (Trincasi^s). Strictly speaking, anaemia is never a disease of the blood.i64 The blood is a tissue in a sense, but is better described as a transport agent, and is only temporarily damaged by any deleterious substances that happen to be taken up by it. In other words, we may say that when toxins of any kind enter the blood and damage its cells or plasma in situ, we have a pollution of the blood, a mechanical process exactly analogous * This statement is not meant to imply that the counts should be hurried over ; they should be reasonably accurate. The beginner requires to exercise especial care in the technique of blood-counting. Plastic Phenomena of Erythropoiesis 101 to sewage pollution of rivers. We do not say the rivers are diseased ; we know that if the pollution be prevented the river becomes wholesome once more. In the same way, if we could find out and counteract what is contaminating the blood in some anaemias, the patient would at once be restored to health. A good example of this is shown by employees who are notoriously anaemic while working in certain factories, but recover a natural white-race colour as soon as they change their occupation and come to live in other districts. Even though the circulating blood were damaged by a noxious agent, there would still be no anaemia if the red-cell-forming organs (we assmne it is the red cells that are damaged) made new sound erythrocytes rapidly enough to supersede the damaged ones. Anaemia implies that the normal equilibrium between destruction and new formation is lost ; the destruction is in excess of formation. That is to say, anaemia requires simultaneous insufficiency of the bone-marrow for its consummation. This is what Pappenheim calls myelopathy. Loss of blood, by itself, is not anaemia. Loss of blood flus defective renewal, from whatever cause = anaemia. Classification. — The following groups of conditions may be met with in different cases : — 1. Stimulus to make blood is constant ; marrow inadequate. This is a myelophthisic ancBmia (Pappenheim*). It occurs in two forms : the haemomyelotoxic and the myelometaplastic. 2. Stimulus to make blood is excessive ; the marrow is normal. Here the excessive loss of blood cannot be replaced at once, but the anaemia ultimately disappears. If the marrow fails, and regeneration of blood is inadequate, then a myelopathy is super- added. Sub-varieties : (a) Pure traumatic ; (6) Toxogenic, e.g., morbus Werlhofii. These are all " hcBmatic ancBmias." 3. Stimulus to make blood is excessive and marrow ijtiadequate = aplastic forms. 4. Haemolysis of blood, marrow normal. This is a hcemolytic ancemia. It may be associated with jaundice (Widal and * In pernicious anaemia there is destruction of the original bone-manow and disappearance cif the cytadenoid reticular tissue (Donzello^'"). 102 Biology of the Blood-cells Abramii65). in addition to a true haemolytic action, the red cells are found to be possessed of less resistance. Examples : strepto- coccic, staphylococcic, colon, typhoid, M. tetragenus infections may set up hsemolytic anaemias (Cicaterri-Bonoi®®). 5. Hsemolysis of blood, and marrow poisoned also. This is a myelotoxic ancemia. Such effects are produced by experimental injection of rabbits with typhoid toxin. The bone-marrow becomes atrophic (Hirschfeldi^T). 6. Haemolysis of the blood, the bone-marrow altogether pathological. In this case there are unusual methods of regeneration — the mother cells come to be called out as well, and perivascular tissues are called into requisition (vicarious hsemogenesis) in order to attempt to meet the demand. There is myelopathy plus defective erythrogenesis. Example : bothriocephalus, Biermer or pernicious anaemia, haemo-lymph-glands. 7. Toxic action on the blood (non-haemolytic) ; marrow partially adequate, but then breaks down altogether. In this case we deal with a so-called hcem^toxic ancsmia, which may be active or passive (aplastic). 8. Toxic action on the bone-marrow. The blood reflects the changes thereby produced. 9. Failure of marrow to make cells at all. Primary aplastic anaemia. This is hypothetical, and may never be met with. Changes which may be classed as metaplastic, meta-hyper- plastic, and anaplastic and aplastic,* are met with in the lesion- groups designated 6, 7, 8, and 9. The autopsy findings can be interpreted according to the variety of " plasia," because an examination of the marrow for a cytological formula comprising all the stages of development of the red cell (and white cell, see Chapter V.) will show what has taken place. Cases with nearly every cellf a lymphoid haemoblast, or with nearly every cell a megaloblast, or cases with hardly any nucleated red cells at all (the marrow being quite lymphadenoid) — all such would call for description or discussion. A thorough grasp of the normal and * The exact meaning of these terms is necessarily deferred till Chapter VII. t This phrase is really a figure of speech. It means " over 50 per cent." Plastic Phenomena of Erythropoiesis 103 pathological lines of red-cell development enables an exact appreci- ation of the anatomical marrow findings in the different anaemias where actual serious marrow derangement has taken place. It would almost be possible to draw up a table of the possible permuta- tions and combinations between them. There is, then, no specific blood-picture for pernicious anaemia (Pappenheim,i69 Krehli^o)^ any more than for any other anaemia. The appearance of megaloblasts, etc., only indicates the severity of the disease, and the degree of reactive power of the patient. As Grawitzi'^i said, the diagnosis of pernicious anaemia cannot be made from an examination of the blood itself. " The same degenerative and regenerative types of blood formation are equadly well found in other severest anaemias, e.g., in carcinosis." The low leucocyte count and the proportionately high content of albumin are more characteristic. The views as to the nature of pernicious anaemia have been discussed most completely by Pappenheim and the Berliner haemato- logische Gesellschaft. The theories are : — 1. That it is a specific disease primarily seated in the marrow — a func- tional asthenia of the marrow. 2. That it is a secondary result of toxicosis, a sjfmptom of toxic action on the marrow (EhrUch, Engel, Ziegler, Isaac-Mockel). 3. That some cases are primary diseases of the blood and others are dual conditions in which the blood and marrow are simultaneously diseased — myelotoxicosis + haemotoxicosis, or hsemotoxicosis alone (Ehrlich-Lazarus view). The appearance of the megaloblast is here taken to be the absolute sign of poisoning of the marrow tissue. The cases with dual action are exemplified by the bothriocephalus-anaemia, in which the poison of the worm, acts on the circulating cells first and the marrow very soon after. As soon as the marrow is involved, megaloblasts appear. 4. Pappenheim's view — that there is only a difference of degree between the primary and secondary anaemias. The so-called primary pernicious anaemias are merely cr5rptogenetic, the secondary pernicious anaemias are to be traced to a known causative process (tape- worm, puerperal disease, etc.). The blood shows toxicosis in each just as much as the marrow, but in some the hffimotoxicosis is more conspicuous ; in others the myelotoxicosis. If regeneration is being undertaken, then megaloblasts will appear in the circu- lation, otherwise not. If " not," the case is to be called " aplastic."* But * Yet it must be remembered that one cannot diagnose aplastic anaemia with certainty till after death, because something may hold back the " blast " forms, and their absence in the blood-film may be misleading. 104 Biology of the Blood-cells the fact that megaloblasts appear, and not normoblasts, is a sign that the marrow is poisoned, because that is not a natural mode of regeneration. The following schemata are given by Pappenheim to express the differ- ences in the haemopoiesis met with under healthy and morbid conditions : — Health. — Lymphoidoc3rte ->- young megaloblast Macro-l3nnphoidocjrte ->- young normoblast -»■ old pycnotic normoblast -^ -*■ normocyte with Jolly body ->■ loss of nucleus by karyolysis -^ finished normocyte. Simple antemia. — L3rmphoidoc3rte -»-young megaloblast -^ old pycnotic megaloblast -> macroc3rte . Macrolymphoidocyte -> normoblast ->■ normocyte. Pernicious An■ old pycnotic megaloblast I karyorrhexis -> macrocyte -<- caryolysis. Young normoblast ->• loss of nucleus by caryorrhexis -> finished normocyte. The whole subject of the nature of anaemia is comprised in the above few charts. The actual mechanism by which metaplasia, anaplasia, or aplasia is brought about remains unknown. It would be extremely valuable to know what atom-groups play a part in these processes. Could we influence metaplasia, or counteract aplasia ? The obser- vations which have been made upon the action of such agents as x-rays, mesothorium, etc., show us that there is hope for effective work in these directions. As we shall show later, bodies containing imid-groupings can alter the rate of multiplication of marrow-cells belonging to the white cell series, so that there is a little light shed on the problem of leucocytosis and leucopenia. We require know- ledge on the analogous process of polycythaemia and anaemia. It is difficult to reconcile the classifications of anaemias which have been presented by the leading authorities of the day. That of Grawitz bore a practical stamp, that of Pappenheim a scientifi- cally complete form. In presenting the following table, we mainly foUow the latter author, inserting the names of the various " diseases of the blood " whenever they can be placed. Plastic Phenomena of Erythropoiesis 105 I. — Anaemias with primary destructive action on the blood itself (hEematic-haemophthisic anaemia). 1. Simple post-haemorrhagic anaemia. This is never aplastic, only normoblastic. Varieties. — (a) Acute (traumatic, puerperal, experimental, thera- peutic). (6) Chronic, i.e., repeated in small doses (piles, repeated haemoptysis, endometrial haemorrhage from fibroids). 2. Plasmogenic anaemia (drainage of albumins from plasma). 3. Haemotoxic anaemia. — ^Haemorrhages under mucous membranes. — (a). The effect of simple solution of red cells (erythrolytic blood poisons). This form is hypochromic ; each red cell contains less Hb than usual, (i). With normoblasts in the blood, (ii). With megaloblasts in the blood. This indicates that the marrow has become involved in the toxic agent, (iii). Aplastic ; no regeneration taking place.* (6). The effect of agglutinating blood poisons, (c). The effect of poisons causing changes in the haemoglobin (hyper- chromia), allomorphic change of haemoglobin added to the erjrthrolysis. (i). With leucocytosis : Example : pjrrodin, poisoning (experi- mental), splenic anaemia, leukanaemia. (ii). With lymphoc3rtosis : (a). Cause obvious (phanerogenetic anaemias). Example: cancer, puerperal anaemia, v. Jaksch's anaemia, syphilitic anaemia, tapeworm. (/3). Cause obscure (cr3^togenetic anaemia). Example: pernicious anaemia, Addisonian. {d). The effect of parasites (e.g., malaria), (e). The effect of micro-organisms : morbus maculosus. II. Anaemias with primary diseases of the marrow (myelopathic anae- mias). Here there are primary or secondary hypermetaplastic changes in the bone-marrow. This includes such diseases as Kahler's disease (multiple myeloma with blood-changes), secondary deposits of cancer in bones, * This is a figure of speech. Even in the most severe anaBmias there must be some regeneration, because all the red cells would be dissolved, and the blood-stream be absolutely empty in ten days, unless we are to assume a simultaneous stoppage of red-cell destruction. The latter is absurd on the face of it, because the disease was first instituted by the very fact of increased red-cell destruction. Aplastic anaemia is only diagnosed intra vitam by noting the presence of polychromato- philia and nucleated reds (Hirschfeld"'). The bone-marrow may be full of micromyelo- blasts. 106 Biology of the Blood-cells medullary aleuksemia, acute lymphatic anaemia ; cirrhogenic poison of Banti's disease ; osteosclerosis. Here comes chlorosis — functional derangement of Hb-manufac- ture. It will be seen that such terms as chlorosis, pernicious anaemia, and Banti's disease are convenient, but they do not afford any better information to either clinician or patient. The root of the disease requires to be elucidated. Finding ourselves, as we do, in a position of being unable to decide between some of these conditions intra vitam, investigations must be made towards that very direction, so that metabolic or other methods of physical examination shall provide the required clue to diagnosis. A new interest thus becomes attached to the blood-counting procedures. We do not find ourselves rigidly boimd to count up the corpuscles to the " uttermost farthing," but we search for abnormal forms in the films, we trace out the process of haemo- genesis going on in that particular patient, and ascertain as far as possible what abnormalities there are. We ascertain the ratio between the destruction of red cells (the regenerative stimulus) and the regenerative reaction to that stimulus. Is this ratio unity less or more ? The microscopic and chemical evidence which enables the first part of this ratio to be determined has been set forth. The evidence of regeneration lies in the detection of the ancestral forms in the blood-stream, or in examination of the marrow during life. The process of regenera- tion is, of course, the same as the ordinary process of development, although details may be modified here and there. The rules given for the study of leucocytosis can be followed in studying anaemia ; we note that a slight grade of anaemia only leads to a call out of the reserve cells already present in the marrow, and there need be no obvious morphological change in the red cell. In cases of repeated haemorrhages, the reserves will be drained until active manufacture of red cells is necessitated. If the production be less than the demand, nucleated forms will appear — " deviation to the left." Since the bone-marrow is a dual organ, defects in red-ceU proliferation will simultaneously alter leucocytic development. Either a paresis will take place, causing leucopenia, or undue Plastic Phenomena of Erythropoiesis 107 stimulation of these cells wiU ensue and the anaemia will come to be associated with leucocytosis. The toxic bodies liberated by multiple haemorrhages will suffice to produce such an effect. Briefly stated, the clinical evidences of regeneration are : (i) Appearance of nucleated red cells in the films ; (2) Poly- chromatophilia ; (3) Changes in the chemical composition of the plasma (notably the phosphorus)* ; (4) Changes in the urine (bilinogen, e.g.). Zoja^' divides the anaemias into two groups according to the amount of bilirubin present in the urine. In the first class the amount is increased, showing that haemolysis is more intense than usual. Two varieties may be met with here : — 1 . Where (a) many of the erythroc5rtes show reticular substance ; (b) The punctate basophilia is not present ; (c) Where the Jolly bodies are absent, as well as normoblasts and megalocytes. The red cells showing destruction are very numerous. (The points to note are : Number of damaged red cells, excretion of bilinogen, total red-cell count and Hb-content). 2. Where (o) many of the erythrocytes show reticular substance with vital staining, though they are not so numerous as in (i, b) punctate basophilia is present, (c) normoblasts, and occasionally megaloblasts are seen. (Example : Plumbism, pernicious anaemia, leukanaemia, leukaemia, aleukaemia). The explanation of the phenomena lies with the explanation of the automatic regulation of the destruction and regeneration of the red cells {see p. 74) . In the pathological conditions referred to, a new factor of equili- brium may be set up, which can be determined by study of the blood and the bilinogen content. There are two possibilities regarding the cause of the change in the equilibrium : (i) Either the blood cells which are broken up leave auto-isoljrtic substances behind them, which call forth an antibody formation on the part of the organism ; or (2) Some metabolic products or bacterial products are present which act as irritants for haemopoiesis. (Cf. Ross, researches on induced cell-proliferation, referred to on p. 241.) In the first case, the autolytic substances (eiythrolyiic in the case under considera- tion) are hardly toxic, and only excite increased activity on the part of the bone-marrow cells. If the substances in question are not autochthonous, they must be of toxic or infective origin, and set up cytogenetic stimuli which bring about the appearance in the blood of immature cell elements, thus explaining aplastic anaemia or leukaemia. Fo^ (1910) was able to induce complete aplasia of the bone-marrow by injecting a small quantity of highly •According to Gibelli,^" the serum of a bled animal contains hsmopoietins, which, injected into another animal, will excite red-cell formation (regeneration). The same phenomenon is exhibited by the injection of lipoids into anaemic animals, or by the injection of lecithin alone (Kapinow"*). In other words, the good effect on regeneration of red cells occmring after saline infusion is due to the action of the lipoids liberated by the red cells broken down by the action of the saline. 108 Biology of the Blood-cells toxic serum into a rabbit or guinea-pig ; he also established a similarity between infantile splenic anaemia and the hasmol3rtic ansemia experimentally induced by splenotoxic sera. In the case of (2), we have the observations of Ferrata, which show that an inorganic poison or substance may be necessary before an infective agent may act. This hypothesis applies more particularly to the anaemias associ- ated with leukaemia, aleukaemia, and Banti's disease ; the blood may be damaged at the same time as is the haemopoietic apparatus. Varying or increasing toxicity of the virus may account for the conversion of one type of leukaemia into another, or one kind of severe anaemia into another. In this way we come to appreciate the instability of the equilibrium of the blood-forming mechanism during health. At any moment, from causes entirely beyond our ken, we may be plunged into a fatal subversion of the cytogenetic processes on which life depends. Sufficient has been said to show the logical connection between the morphological data detailed in the early parts of this chapter and the phenomena observed by the bedside. We have traced out the biology of the red cell — in other words, we have indicated the different phases of its life history under the most varied conditions, and we have seen how pathological influ- ences modify its course. The full discussion of the individual forms of anaemia would lead us too far from the direct line which we desire to follow, and is unnecessary, because the reader has only to bear in mind that they are the result of the play between toxic action on circulating cells and toxic action on the marrow. There is then little difficulty in placing the morbid conditions into a system. The relations between one form of metaplasia and another require brief notice. Can one form of metaplasia pass into another ? We are told that cases of pernicious anaemia may apparently pass into leukaemia, and vice versa. Neither of these statements is true. The two diseases are merely phases of one and the same fundamental process — a condition of leukaemia, a hyperplastic or metahyperplastic disease of the haemopoietic system. The disease may show marked anaemic signs before it becomes clinically manifest as a true leukaemia. The blood may show abnormalities in regard to the white cells without any increase in the total numbers ; it is in a state of " subleukaemia," or latent Plastic Phenomena of Erythropoiesis 109 leukaemia, but the l3Tnphadenoid change which is taking place ultimately brings about impairment of red-cell formation varsdng in degree from the minimal to the condition clinically known as pernicious anaemia. ,,. ^ Polycythaemia. — ^The phenomenon of marked increase in^ erythrocyte content of the blood is much more rare than that of anaemia, although many cases of caxdiac stagnation show a certain degree of polycythaemia so long as the blood be collected from the legs (BJramer^"). A similar blood-state is observed in the newly-born, in persons hving in high altitudes, or at the sea-shore, and in some persons after high living. Such cases are spoken of as physiological polycjrthaemia. Pathological polycythaemia is primary or secondary. The latter includes cases following marked loss of fluid from the body, passive congestion, and the action of certain poisons (tar preparations) . Paroxysmal haemoglobinuria, scurvy, cirrhosis of the hver, tuberculosis involving the spleen, chronic inter- stitial nephritis, Addison's disease, chorea, neurasthenia, are occasional causes (Senator"^'*). True primary polycythemia, or erythrocytosis (erythrcemia) , resembles leukaemia only in the interminable proliferation of the blood-cells. The total volume of the blood is increased, the excretion of iron by the urine is increased, and there is found a h5rperplastic condition of the bone-marrow, the whole of the fatty marrow being converted into active red marrow (Rubinstein'-'^). The enlargement of the spleen which is usually associated with the disease is not primary, because splenectomy does not cure ; otherwise it might be supposed that the explanation of the disease lay in an inabiUty on the part of the spleen to destroy the red ceUs, or even in an active production of an antibody by the spleen which prevents erythrolysis. This view would be in favour of Luce's view that erythraemia is not myelopathic at aU, but of splenic origin.^" 110 CHAPTER III. ON THE LYMPHOCYTE. Section I. — ^The Factories of the Lymphocyte : The lymph node as a whole — ^The lymph follicle — Cyclical changes in the lymph follicle — Metabolic changes in the lymph nodes^Regressive changes — Functions of lymph nodes — Relation to digestion — ^The spleen — ^The Malpighian follicle — ^The accessory factories of lymphopoiesis. Section II. — ^The Lymphoblastic Line of Development : The morphological characters of the lymphoblast — Of the large lymphocyte — Of the germ-centre cell — Of the meso-lymphocyte — ^The cycle of development. Section III. — ^The Lymphocyte of the Blood-stream : The lymphoid elements of the blood — Morphology of the lymphocyte — ^The differential diagnosis of the lymphocyte — ^The functions of the lympho- cyte — Lymphocjrtosis and lymphopenia — ^The nutrioid function — The adsorptoid function — relation to phagocytosis — ^The chemistry of the lymphocyte ; of its azur granules — ^The comparative cytology of the lymphocyte. Section IV. — ^The Fate of the Lymphocyte : Cytometaplasias. The Factories of the Lymphocyte 111 I.— THE FACTORIES OF THE LYMPHOCYTE. The lymph node as a whole — The lymph follicle — Cyclical changes in the lymph follicle — ^Metabolic changes in the lymph nodes — Regressive changes — Func- tions of lymph nodes — Relation to digestion — The spleen — The Malpighian follicle — Ihe accessory factories of lymphopoiesis. THE term " lymphocyte " is often used in a general sense, in reference to certain cell forms met with both in the blood- stream and in the tissues. The " lymphoid cell " of Pappen- heim is a uninuclear basophile non-granular cell, present in the circulating blood and also scattered throughout the body, though it appears especially congregated in the factories presently to be described. If the term " lymphoid cell " be reserved as a general one, the word " lymphocyte " comes to be applicable only to a cell-form of special function, familiarly present in the blood-stream. Although every lymphocyte is by definition a lymphoid cell, the converse does not hold good. Two other terms are sometimes used which are apt to be misleading. These are (i) The Ijonphocytoid cell — applied to any cell which closely resembles a true Ijmiphocyte in morphology, remains non-granular, but is not necessarily identical with it ; (2) The lymphadenoid cell — applied to any lymphoid cell derived from a lymph-cell-forming tissue. The word lymphocyte is ambiguous in another sense. Some haemato- logists attach a purely morphological meaning to it, while others prefer to add a genetic significance. Thus, according to Naegeli, Schridde, Helly, Ziegler, Turk, and others, every true lymphocyte has come from the lymphatic apparatus — ^it is a histiogenetic entity. If we define the lympho- C5rte solely according to its morphological characters (after Maximow and Weidenreich) . it becomes inevitable to include with it a number of forms which it is hard to reconcile with the popular conception of lymphocyte. This accounts for the prevalence of the lymphocyte in the literature of haemogenesis, and introduces an undesirable confusion into haematology. For the purposes of the present chapter, therefore, we disregard pre-natal lymphocytes, in order to deal more fuUy with the cell so well known in the blood-film. The fact that blood-lymphocytes are so much intermingled in the factories with other lymphoid cells, causes a little difficulty in describing the lymphopoietic factories according to the heading of this 112 Biology of the Blood-cells section. The reader is therefore referred to the corresponding section of the succeeding chapter for a concluding survey of these tissues as a whole, as well as to the later chapters, where all manner of lymphoid cells are dealt with in perspective. Dividing lymphoid cells (spongioplasmatic cells) into two groups accord- ing to their future history, it is possible to assign them to special tissues. We have (i) Those which remain permanently basophile ; these are the lymphocytes and monocytes ; and (2) Those which undergo oxyplasmasia with or without formation of specific products ; these are the lymphoidocytes {Chapter I) and the leucoblasts {Chapter V). Lymphoid cells are manufactured in the following parts of the body : the lymph nodes, the tonsUs, the lymphatic follicles of the mucous membranes (e.g., solitary follicles and Peyer's patches of the intestine), the spleen, the lymphatic cell aggregations in organs (the so-called Ribbert's lymphomas^ in the liver, kidney, lung), the mesentery (Weidenreichi) ; and indeed in the connective tissue throughout the body,* the th5mius,f and the bone-marrow.J In using the term " lymphoid cell " in relation to these organs, we imply that the lymphocyte is not the only kind of cell made in them. The lymph node is made up of lymph folUcles and medulla ; the spleen is made up of Malpighian (i.e., lymph) follicles and pulp. In each case it is only the lymph follicles which are concerned with the formation of lymphocytes, although, as we shall show, it is probable that if it were not for the medulla and pulp respectively there would be no follicles at all. * It is this widespread distribution that accounts for the absence of blood-change after excision of masses of lymph-glands. t While the thymus is generally accepted as an important lymph-cell factory in the embryo and infant, there are very definite features about its structure which show that the cells made in it are sufficiently distinct from the true small lymphocyte to justify them being renamed " thymocytes." It is for this reason that we shall not describe the structure of the thymus in relation to lymph-ceU factories. The writer feels that at the present day there is not sufficient information about this organ to enable it to be correctly placed in the scheme of presentation adopted in this volume. It will be noticed that Stohr and Grawitz came to a similar conclusion the latter because the thymus lymphocyte never contains azur granules ; they occur when the thymus is not an intra-uterine blood-forming organ. t It has been supposed until comparatively recently (Hedinger,' Schmorl, Lowit) that bone-marrow cannot make true small lymphocytes. If it does not do so, it makes cells which are at least extremely isomorphous with them. Clusters of lymphocytes with genuine germ centres (which proves their lymphatic nature) were found by Oehme in the bone- marrow of children and in cases of status lyinphaticus ; they were in relation to the terminal twigs of the arteries something like a Malpighian body in the spleen, but it is not known whether such nodules were pathological or not. Their structure does not enable a definite statement that they have other functional and cytoplastic potencies, because structure does not prove function. OTr^ c:^ Fii;. zS. — Blood-supplv of Lvriipii Node (foundfd on C;il\-ert). The rtd lines indicate arterial channels, the blue indicate \-enous blood, and the white spaces indicate tlie lymphatic jtaths. Tlie shaded area represents the siiecific tissne. (a) follicles ; (/») pnlp cords below. ollicle sits nn the arter\- like an apple on li stLilk " (p. ii^). l-'l'^. 2^). — MaLPIGHIAX rOLMCLK IX THE SPLEEX. lOc. 2. Zeiss, Apociiruni, 4 mm.). J-'act- /. US] The Factories of the Lymphocyte 113 The Lymph Node. — This is made up of a number of follicles arranged peripherally to the central meduUary tissue, which will in future be spoken of as " pulpar tissue." The latter is completely enclosed by the former save at one point, the point of entry and exit of the blood-vessels. The lymphatic trunks enter over the exterior of the gland, and their channels converge to the point just named. The follicles are severally enclosed in sinuses into which the afferent vessels open. The portion of the sinus beneath the capsule (which covers in the whole organ) is called perifollicular, and is continuous with the sinuses between the follicles (called inter follicular). These again communicate with a very irregular network of lymphatic channels, the central sinuses which separate the pulp cords from one another. The central sinuses converge to form a dense plexus of tortuous and varicose lymph-vessels from which emerge the efferent lymphatic trunks. The follicles and pulpar tissue are also permeated by the circulating lymph, since the reticular tissue which separates them from the channels is as full of perforations as if it were muslin. In consequence, their products of manufacture enter the lymph-stream easily and reach the blood-stream by way of the thoracic duct. It is probable, however, that some of them enter the blood-stream directly, and we shall find that even in the lymph-nodes a discharge of white cells directly into the pulpar blood-vessels takes place by no means infrequently, at any rate in pathological material.* To complete the picture of the lymph node we now follow the blood-vessels (Fig. 28). Entering at the hilum, they break up into main trunks which make directly for the foUicles and usually enter them at their base, so that the foUicle sits on the artery like an apple on a stalk (Fig. 29). Passing onwards through the follicle, the artery breaks up into smaller branches (maple-tree fashion), which at once pass to the periphery of the folHcle and are there gathered together into a mantle-like network of minute venous channels. These rapidly fuse into venous channels and drain towards the " stalk " of the foUicle, and in their turn make • Observations on autopsy material at the Royal Victoria Hospital, Montreal. 8 114 Biology of the Blood-cells straight for the hilum of the gland. This is the cortical system. Similarly, a branch leaves at right angles to the first main vessel and supplies the pulpar tissue. It gives off branches which form a fine capillary network in the pulpar tissue in such a way that the blood-vessel is always in the centre of a pulp cord {see Fig. 36). In this portion of the gland the capillaries are rapidly gathered together into veins (still central with respect to the pulp cord) which steadily increase in size as they join up to form the main trunks that emerge at the hilum in their turn. Sometimes the artery to the medulla gives off a large branch which runs up to the follicle, and vice versa. The architecture of the gland is thus characteristic. We have (i) follicular, and (2) pulpar tissue. The former is built up of arterial trunks, the latter is more related to venous capillaries. Running through the whole there is, of course, a delicate reticulum of connective tissue, the meshes of which are finest at the peri- phery of the follicle, at the margins of the pulpar cords, and along the main vascular trunks. This reticulum is covered by endo- thelial cells, which play a very important part in the functions of the follicle. The Lymphoid Follicle. — In the main, the structure of the lymphoid follicle is the same whether it be in the lymph node, or tonsil, intestinal mucous membrane, etc. In many cases* there is a cluster of large cells in the centre, forming the so-called germ- centre first described by Flemming^ {see Fig. 4). The remaining cells are small round cells of lymphoid character, and are more numerous at the periphery. These lymphoid cells are of two types : (i) A lymphocyte with a dark nucleus, around which one cannot distinguish a distinct cytoplasm ; (2) A lymphocyte whose nucleus is larger, less darkly stained, and enclosed by a delicate protoplasmic border. Permeating amongst all the cells is a delicate connective-tissue reticulum whose meshes are open in the centre and blend with the adventitial cells of the capillaries which traverse the folHcle, while they are continuously finer towards the periphery. The reticulum is everywhere covered by ramifying cells, and. ' Pappenheim points out that the germ centre is by no means as constant as is usually supposed.' The Factories of the Lymphocyte 115 indeed, 'is derived from these. Here and there ordinary white fibrils occur in variable number, and sometimes a few elastic fibrils are also present (Bunting)." Many of the branching cells which go to form the reticulum £ire actively phagocytic, as indicated by the presence of carbon particles within them in cases of anthracotic glands. They are therefore pathologically identical with the endo- thelial cells which become desquamated in the sinuses in catarrhal conditions, and are also continuous with those lining the efferent Ijnnphatic trunks. The germ-centres are not distinct in embryos, young animals, or in very old ones (Baum and Halle). « It is therefore believed by Naegeli^ and others that the small l5nnpho- cyte of the resting follicles makes germ-centre cells, and that the latter mitose and give rise to new generations of lymphoc5^es. Cyclical Changes in the Lymph Follicle. — The germ-centre ceUs, as usually described, are large and densely packed. They frequently show active mitoses, the products of their division being l5anphocytes of progressively smaller size. These are pressed against the fine reticulum at the periphery of the foIUcle, whence they ooze into the Ijnnph-channels enclosing them. These Ijmipho- cytes form a barrier of variable thickness roimd the central pale ceUs. However, the germ-centre only represents a transient stage in the life history of the follicle, and is always changing in form. Thus, during the fasting period, the germ-centres are specially rich in mitoses, the cell body has a granular appearance and is more basophile in reaction, the sinuses are empty, and the vasculsir channels very narrow. During digestion, the foUicles of any gland — not merely the mesenteric nodes and the sohtarj^ follicles (Pirone)i° — swell markedly, their outlines become indistinct owing to an ever- increasing amount of l\-mphoid cells at the periphery, the blood- vessels dilate, and the l\"mphatic sinuses are seen to be filled with macrophages (desquamated endothehal cells) whose c\i;oplasm mav contain red and white cells. The phagocj-tes become extremelj' active at this period (their feeding time), their contom: becomes less irregular, and their nucleus is placed to one side, while the <;5rtoplasm of the germ-centre ceUs themselves becomes abundant, the nucleus becomes larger, round or o\^ or reniform, and its structure clearer, but mitoses are less numerous than before. 116 Biology of the Blood-cells Keutheii found that the germ-centre cells of the mesenteric glands take up egg-yolk from the food directly. The writer has found that human mesenteric glands are flooded with soaps in globular form for some hours after food, this fat being retained in the endothelial cells of the sinuses, to be passed on into the circulation in another form at a later hour. In other words, much of the fat received dur- ing digestion is stored in these cells until required by the organism. Similar changes to the above take place in the endothelial lining of the capillaries. After a certain number of hours the follicle begins to diminish its activity, its outline shrinks, and the germ-centre cells appear relatively more numerous, until finally the same appearance is reproduced that was described as present in the fasting stage. In a sense, this second appearance is equivalent to the resting stage of a secretory gland ; the follicle is now empty of the lymphocytes, and the original formative cells are exposed to view, just as a secretory gland-cell loses its turbid appearance after digestion because of loss of the secretion that had accumu- lated during the fasting period. The explanation of the cyclical changes in such terms is misleading. Observations on the foUicles in numerous cases of appendicitis have led the writer to regard the process of lymphocyte formation as continuous. In other words, there is no resting stage. The differences of appearance are due to the variations in demand upon the cells manufactured. In infections the lymphocytes may be sucked up from the follicles very rapidly, and this process may continue day after day, whereas during digestion the demand only lasts an hour or two. The richness or otherwise in germ-centre cells, therefore, depends on the demand of the tissues for lymphocytes. Germ-centre cells are of course always there, although the individuals are regularly disappearing as a result of mitosis. The phenomena are, then, exactly analogous to those observed, for instance, in a reservoir where the degree of fullness or emptiness depends upon the outflow, assuming the inflow to be constant.* • This is not necessarily an altogether accurate representation of the processes under consideration. Pappeuheim * points out that germ-centre cells are not always in the form of macrolymphocytes with narrow cell-body, and that in hyperplastic foUicles (e.g. tjfphoid fever) they vary in character from the above-named form of macrolymphocyte to large The Factories of the Lymphocyte 117 The rate of increase of the lymphocytic cells is sometimes so rapid that no other conclusion can be reached than that the inter- mediate stages can proliferate parthenogenetically, as it were, and produce large groups of lymphocytes in place of small ones. The appearances seen when the folUcle is rich in lymphoid cells suggest this explanation, the more so as their arrangement into locules proves that they have been derived by multiphcation into five, six, or more, from a smaU round central cell. Bearing on this view is the fact that in chronic lymphatic leukaemia the lymph-nodes show no germ-centres.io Metabolic Changes in the Lymph Nodes. — Flemmings found that the germ centres contained rounded or semilunar bodies which have a strong affinity for basic dyes — the " tingible bodies." These are situated in the cell-body of macrophages, and some authors find them in lymphoid cells. They resist acetic acid, but dissolve in alkalies. They stain well with hsematin and all basic aniline dyes. They stain metachromatically with thiazin dyes, and can be double-stained in some instances, the hoUow of the semi- lunar body having an affinity for acid dyes, while the rest of it has an affinity for basic dyes. According to Ciaccio,i3 they are associated with the fact that purins are very rich in lymphoid tissue, and have something to do with the digestion of nuclear matter by macro- phages. This is a katabolic process. The fixed follicle cell or the endothelial cell becomes large, its nucleus clear and round, and its cytoplasm finely granular and basophUe ; while els the katabolic process progresses, it becomes more acidophile and delicately reticular in structure. The ingested material now appears within the cell as the tingible bodies referred to. In hunger, fat in the lymph nodes is always within the endo- thelial cells and wandering cells. The fat undergoes two changes : (i) Emulsification and saponification under the influence of the mononuclear forms and cells of the type of Saxer's wandering cells. In many follicles the germ-centres are reduced to a minimal perivascular envelope without any visible mitoses. He claims that normally there are no true germ centres ; that the appearance of broad- bodied (leucocytoid) cells is pathological. The absence of follicles in cases of chronic lymphatic leukaemia is explained as the efifect of continued proliferation by amitosis to the exclusion of the previously existing slow proliferation by mitotic methods. Similar state- ments are made by Schmidt. The writer would consider that the whole subject is still in a nebulous stage. 118 Biology of the Blood-cells endothelial cells of the sinus ; (2) Conversion into neutral fat, which appears in the foirm of extremely fine granules. The latter change is under the influence of the Altmann granules, the first stage being acted on to produce the second. These processes take place both in the case of autochthonous and heterocthonous fat (Stheemann).!* Regressive Changes. — Conversion of the proper tissue of a lymph node into adipose tissue is noticeable just as it is in the case of bone-marrow. The germ centres lose their cells, and the connective-tissue cells become adipose. This change begins in the hilum and spreads to the capsule, so that nothing is ultimately left but a narrow disconnected rim of l3TTiphadenoid tissue. After this, fibrosis may take place in the vicinity (Rubens-Duval et Fage).is Conversely, adipose tissue may develop lymph-nodes in regions previously devoid of them. Functions of the Lymph Nodes. — 1. It has long been supposed that the main function of the lymph node is to provide a barrier to infection* This being so, it is remarkable how seldom they prove adequate. It is only the least virulent organisms that fail to pass through them, and even here it is doubtful whether the destruc- tion of the organism does not rather take place in the subcutaneous tissues previously. The arguments for believing that they act as a barrier to infection are such as follow : {a) Intravenous infection is far more dangerous than subcutaneous ; (6) Administration of toxins subcutaneously to a guinea-pig causes necrosis in the follicles, whereas toxin, plus antitoxin, leads to increased reaction of the lymph follicles ; (c) Streptococci taken from a wound infected with erysipelas kiUed a rabbit in four days. If taken from the lymph nodes in the same case, the rabbit does not die for sixty days (Labbe, Bezancon) ; [d) Maceration of lymph-node tissue at 38° C. yields a thermolabile haemolysin, which is destroyed by 56° C. It is able to activate an inactive serum just like haemolytic complement (Metchnikoff and Tarassewitsch,!" and others). 2. The absorption of body or food fat by way of endothelial cells (lipo- phages) and conversion of the same into soaps and back again into neutral fat. A relation of follicles to digestion is implied by their superabundance in the alimentary tract, which indicates that such function is much more important than anti-microbic action. It is therefore a matter of no surprise that recent observations of the follicles of the tonsil (MacLachlan,'^' 19 12) * a. Bactericidal (Bartel, Denys, Wassermann). b. Antitoxic (Aslier). The Factories of the Lymphocyte 119 fail to show any evidence that this organ has anjrthing to do with anti- microbic processes, in spite of the overwhelming belief to the contrary. 3. Formation of macrophages and phagocytosis of carbon particles, red and white cells, etc. 4. Cytogenesis of lymphocytes. Ehrlich thought that lymphocytes entered the circulation passively, but Jolly and others found them to be amoeboid. 5. Pathologically, metaplasias of all kinds, myelopoiesis. The Structure of the Spleen. — This differs from that of the lymph nodes, inasmuch as the follicular tissue is relatively scanty, while the pulp tissue is abundant. The organ is divided up into a number of lobes by bands of fibrous tissue, the trabeculae, which pass inwards from the capsule. These lobes are again sub- divided into lobules, each of which is about a millimetre in diameter. This lobule is the unit of the organ. It is roughly pyramidal in form, the base being outwards and the apex inwards ; fibrous bands traverse it and divide it into about ten compartments. The main artery of the lobule enters at the apex of the pyramid, passes straight to the base, giving off on its way a separate arteriole to each compartment {Fig. 30.) This arteriole ends in an ampulla (the ampulla of Thoma), the proximal two-thirds of which are lined by spindle-cells lying on a delicate reticulum, while the distal third has no definite cell boundaries and shows fibrils of reticulum passing across it. Between this imperfect terminal and the intralobular vein is the pulp cord of the spleen, so that the blood traverses the latter in its way from arterial to venous chajmel. The intralobular veins empty into the interlobular vein which runs along the side of the p5nramid to join similar vessels from adjoining lobules, and ultimately merge into the splenic vein. Shortly after the main artery of the lobule enters the pyramid, it passes through a mass of lymphoid tissue — the Malpighian foUicle. In diseased conditions, such as atheroma, this passage is well marked and conspicuous, owing to tortuosity and increased thickness of the vessel {Fig. 31). This main trunk bears with it a lymphatic sheath, and it is in the latter that the folHcle develops. The above sketch is completed by filling in : {a) A delicate fibrillar network of connective tissue throughout the organ, passing across in web fashion from one intralobular trabecula to another ; 120 Biology of the Blood-cells and (6) Sensory medullated and sympathetic non-medullated nerve fibrils, the latter being the more numerous and following the arterial ramifications to end either in the arterial muscle fibres or free in the pulp. The Malpighian Follicle as it appears in the Spleen. — There are some slight differences of structure in the Malpighian body which require definition. The exact form of the follicle varies not only in animals but even in man.* Thus the tissue may be entirely on one side of the follicular artery, but more usually it completely envelops the artery. The artery may run exactly through its centre, or more to one side (excentric follicle). Some- times the follicle appears as an elongated branching structure, which follows the artery through one or more branches and consti- tutes a tubular or sheath-like envelope to the vessel.f {Fig. 32). The centre of the structure is composed of germ-centre cells, while the periphery is formed of small round lymphoid cells, just as was described for the follicle. During digestion, changes may be noted in it similar to those that are noted in the lymphatic tissues of the intestine, namely, enlargement . of the follicle, increase in the size of the germ centres, and the appearance of macrophages at the periphery. Basoplule cells are numerous at this time ; their nucleus is characteristic — two or three large central granula- tions, joined by delicate chromatic filaments. The cell-body is finely granular during mitosis. Plasma cells and macrophages with abundant cytoplasm and vacuolar inclusions are noted, showing that the Malpighian bodies have something to do with haemolysis and leucolysis during digestion (Ciaccioi^). Conversely, during fasting, the follicles are small and sharply defined ; they are then reduced to a ring of lymphocytes of small size round the central arteriole. The reticular tissue is, however, rather different. It is a very open meshwork ever3rwhere but at the extreme periphery of the mass, where it is much more dense — denser even than at the periphery of a lymph-node follicle. As the meshwork of the lymphatic follicle communicates with the surrounding sinus, so * Observations on autopsy material. fThis arrangement is frequent in the rat. Fig. 30. — A View of the Arterial Supply of the SPLEE^f. The splenic arterj' was injected with barium sulphate, and the viscus photographed by means of ,v-ra>'3. Notice the hea^'y trunks passing parallel to one another almost to the free surface. Each supplies a separate " crmipartment," and therein breaks up into a complex briishwork. {From a pholograph kindlv pyeparcd by Dr. A. Howard Pirie.) " In diseased conditions, such as'atheroma, this passage is well marked and conspicuous, owing to tortuosity and increased thickness of the vessel " (p. 119}. Fi(^. 31. — Centre of :Malpighian Follicle, with diseased central arteriole, {a a) sections of one arteriole. Its to-and-fro twisting causes it to be cut through several times within a short distance ; (b) deposit of connective tissue round the vessel; (f) follicular cells. (Oc. 4, Zeiss, A]jochroni. 4 mm.}, />,r^ />. 730] ■' Sometimes the follicle appears as an elongated . . . structure which . . . constitutes a tubular or sheath-like envelope to the vessel " (p. 120). p,„ 32. Anomalous Shape of JIalpighian Follicle, (a a) the follicle, surrounding (ft) an artery cut longitudinallv ; (c> pulpar tissue. (Oc. 2, Zfiss Apochrcim. 4 mm.). "... such collection (of lymphoid cells) ma>' undergo hypertrophy aud give rise to a . . . focus of cytoplastic activity . . . from which some (lymphoid cells} ooze into the blood-channel direct" (p. 122). F(^. 33.^Edge of a Capillary showing discharge of I^ywphoid Cells from an adjacent Follicle into the lumen. (Oc. 6, Zeiss Apochroni. 4 mm.). The Factories of the Lymphocyte 121 the meshwork of the Malpighian body communicates with the spleen pulp, there being no apparent lymph-sinus system in the spleen. The vascular supply of the Malpighian foUicle is also different. The mass is built round a vessel only in the sense of the perivascular lymph-sheath being dilated enormously at this particular spot. A few minute arterial trunks leave the main vessel rectangularly as it courses through the cell cluster, branch rapidly into smaller and smaller branches which make for the periphery of the follicle, and finally pass through into the pulp tissue, to end there somewhat as they do in the final compartments of the lobule. A further distinction between the Malpighian and the lymph- node follicle lies in the character of the non-lymphoid cells which may be present. In sections of the spleen taken from subjects d5dng of various conditions, it is frequently noticed that the edge of the foUicle may be infiltrated by certain other forms of cells which are only scanty in the lymph-node follicle. First and fore- most of these is the pseudo-plasma cell, which, in some conditions, is extremely densely crowded around the foUicle.is Eosinophile cells are also very frequent in the vicinity of these follicles, while in the lymph-node they lie in the peripheral sinuses.* The fact that the lymph-follicle ceU contains phenolphilic granules while that of the spleen follicle does not, is also of interest (Loele^o). These granules are the more numerous the nearer they are to the arterial blood. The pathological changes occurring in the Malpighian bodies are of importance and of considerable interest in so far as they provide data which would elucidate the nature of the constituent cells, but these will be referred to elsewhere. The Bone-marrow {see p. 47). — It is usually pathological for lympho- cjrtes to be formed here, f The following evidence suggests that it may be a physiological event also, (a) A thoracic-duct fistula is made in the dog so that lymphocytes cannot enter the blood. The spleen is now excised. The result is lymphopenia for a short time ; lymphocytosis follows (Biedl and * In each tissue, however, the eosinophile cell is not a true eosinophile cell (blood cell) osition. The reader will observe that each cell-form is represented as ever changing in some way, either in characters or in position. A change in position is only indicated by the appearance of a cell-form in an area depicted of another colour ; change of position does not follow the curves. Thus, when 2 becomes 3 it is depicted as still on the brown-tinted rectangle. It is still in the follicle. The cell, then, has not actually moved. Again, cells 4 and 1 6 are both in the white area. They would both be actually on the same spot. But cell 6 has actually moved to 6'. ® (9 6 6- 13 15 20 zs Diagrammatic OnniNES of Cells referred to in Plate III, drawn to scale, using a magnification Oc. 12, with Zeiss Oil-immersion lens. Panoptic stain-preparations in the author's collection. In all these cells a white cytoplasm means feeble basophilia; a stippled cytoplasm means moderate basophilia ; and line-shading implies a conspicuous degree of basophilia. Similarly, varying degrees of basophilia in the nucleus are indicated by increasing density of shading, commencing with white (represents the palest blue in the preparation), and passing to dense black (trachychromatism). The small dots m the nudeus are chromatic markings, while the larger ones, except in cell 11, are the nucleoli Azur granulation is not indicated. 1. — Adventitial or perithelial cell ; the primordial resting cell. g. — Lymphoidooyte ; mother cell, or wandering ceU of Saxer. S. Lymphoblastic macrolymphocyte, or germ- centre cell. 4. — Splenocytar monocyte, or indifferent pulp cell. 5. — Mesolymphocyte. 5' the same in the blood (Plate IV, 5). 6. — Microlymphocyte, or tissue lymphoctye ; the lymphoid cell of the follicle ; 6' the same in the interfoUicular tissue ; 6" in the blood (Plate IV, 2) ; 6'" in the tissue-space. 7. — Stroma cell of the interfoUicular tissue 5.— Myelolymphocyte (Plate IV, 8). 9. — Leucocytoid lymphoidocyte (Plate IV 38). m— Rieder lymphoidocyte (Plate IV, 40). ii.— Leucocytoid macrolymphocyte ■ 21 the same becoming plasmoid. M. — Macrolymphocytar plasma cell. 13. — Lymphoma cell. 14. — Mesolymphocytar- plasma cell. 15. — Dwarf microlymphocyte ; 15' the same m the blood (Plate IV, 6). J6.— Splenocytar monocyte, splenocyte, or large mononuclear leucocyte; 16', the same in the blood (Plate IV, 10). 17.— Lymphocytoid large mononuclear leucocyte. 15.— Transitional cell (Plate IV, 11). 19.— Leucocytoid large mononuclear ; 19', the same in the blood (Plate IV, 12). »— Leucocytoid mesolymphocyte. gl. — Lymphocyte with reniform nucleus (Plate IV, 4). gf Leuco- cytoid lymphocyte (" hyaline leucocyte "), (Plate IV, 3). ^3.— Lymphamic lymphocyte (Plate IV 44, 45). ^^.— Myelolymphocyte (Plate IV, 8). S5.— Histioid plasma cell, ge.— Colostrum cell. g7.— Thrombocyte of reptUian blood. ! d a o I D- s •^ > ►~l ■-^ u. o ti) H UJ ■^ S ►~1 LU Uh I o en m (£ O I 1- 3nssij_ 3Aiivwaoj The Lymphoblastic Line of Development 127 allied to the leucoblast series (myeloblast) than to the lymphatic. It is therefore better considered under that heading. The descrip- tion of such a cell in words would leave no clear idea of any distinc- tions, whereas a drawing at once indicates the differences. Such cells are sometimes " large," and sometimes " small." The Morphological Characters of the Large Lymphocyte.* — Outer Form. — ^The size of the cell is variable. The cell may be a little smaller than the lymphoblast, inasmuch as it is a daughter cell of this. The shape and contour are as before. Internal Structure of the Cell-body. — The cell-body is narrow, stains feebly basophUe, and shows no indications of spongioplasm. The cytoplasm is almost hyaline in aspect. Azur granules are occasionally seen. Nucleus. — The absolute size is large, and the relative size is considerable. The structure is compact, owing to lack of differenti- ation of the chromatin from the parachromatin. Occasionally it is indented. Nucleoli are variable. The Large Lymphocyte of the Tissues, the germ-centre cell, presents very definite features, which are noteworthy because they are readily made out in ordinary histological preparations of tissues. The shape of these cells varies markedly, from spherical through every form of polymorphism to an absolute oval. It may be said that absolutely regular forms seldom appear in the lymphatic follicles of either lymph nodes or spleen. The amount of cytoplasm is also very variable. In not a few instances, it is relatively abundant, but always bears the constant feature of light baso- philia, and in the healthy state, homogeneity of structure. In many diseased conditions of these formative centres a vacuolar degenerative condition of the cytoplasm is noticeable, with the appearance, may be, of dusky granules between the vacuoles. With such degenerative phenomena there is associated a marked lack of distinctness of outUne, and marked irregularity of contour. The extremities of the normal germ-centre cell frequently show an increase of density of cytoplasm in those cases in which a blunt See Plates III., IV. 128 Biology of the Blood-cells spindle shape is assumed, and a very faint but distinct reticular structure can be detected in the cytoplasm at these points.* The nuclear membrane is always well defined in the normal cell, and strongly demarcates the basophile cell-body from the almost achromatic nuclear matter. The parachromatin in these cells is very abundant, leaving the chromatic points very plainly seen ; the latter are especially abundant towards the periphery of the nucleus, where the eye sees more granules because the nuclear matter is observed at an angle. A few chromatic filaments can be observed here and there, connecting distant chromatic points. Sometimes germ-centre cells are seen which are entirely amblychromatic, the cytoplasm Ijeing itself almost achromatic. Nucleoli, or more conspicuous larger masses of chromatin, are some- times seen. True metachromatic nucleoli are not always noticeable. Mitoses are very frequently seen in the germ-centre cell, and indeed, in earlier times the phenomenon of mitosis has been largely studied in this kind of material. It is unnecessary, therefore, to discuss the mitotic forms. The Morphological Characters of the Mesolymphocyte.*!— Size of Cell. — ^This is intermediate between the preceding forms and the small lymphocyte of the blood-stream. Shape of Cell. — Rounded. Usually oval in tissues, but rounded in the blood-stream. Cell-body. — ^Feebly basophile. Sometimes rather deeply baso- phile. There are sometimes a few scattered azur granules, otherwise the cytoplasm is entirely homogeneous. The amount of cytoplasm varies, but it is relatively greater than in the case of the other lymphoid cells. Nucleus. — This stains very deeply, owing to the density of the chromatin. The nucleus is absolutely large, and relatively is less conspicuous than in the preceding lymphoid cells. Nucleolus. — ^This is found in an excentric position. Single. Mitosis. — Reproduction appears to take place by amitosis. The Cycle of Development. — Leaving the characters of the small lymphocyte of the blood-stream on one side for the * See Plates III., IV. t Appears in the blood from the seventh month of foetal life onwards. ■' A hicular arrangemtnt of Ihe cells may be seen, where clusters of eight or mure . . . are iiuticed rniiinl a central l\'mplioblastic form uf cell" (p. i2ij). Fi':,. ^4- — TiiK Central Part of a Lymphoid Follicle, magnified 400 diameters. The red lines demonstrate the cell-groups referred to. The central cell is not in focus. (Oc. 4, Obj. 4 mm.). Fact- /'. /20] The Lymphoblastic Line of Development 129' moment, we have in the above brief descriptions a view of all the links of the chain of development of the cell in question — a series which is extremely simple when compared with that described for the red blood-cell, or even the neutrophile leuco- cyte. It is possible that this simplicity is due in part to lack of knowledge of the details, but seeing that the lymphocyte- forming centres are numerous, and so readily seen in almost any tissue, it is possible for any microscopist to find the genealogy of these cells restricted to a very small series. If the germ-centres of Ijnnphatic follicles be studied by any of the ordinary stains — iron hsematoxylin, eosin and methylene blue, Pappenheim's panoptic stain — they will be found to contain aU grades between the germ- centre cell and the ordinary small lymphocyte. It will not be possible to fix on more than two or three definite cell-forms, because the intermediate stages differ so very slightly from one another. It is easy to point out differences in the sections, and yet there would be no definite criteria for deciding between them were they removed from their original setting. Passing through an intermediate form in which the cytoplasm is rather more basophile and much less conspicuous, while the nucleus is relatively larger but absolutely smaller, we come towards the typical lymphocyte form in which there is hardly any cytoplasmic covering to be seen. These stages are not all seen in successive layers of follicular cells, as if the formative processes acted centrifugally in the follicle as a whole, but they can be seen to take place in many centres scattered through the follicle, each centre being in the vicinity of a capillary vessel. In weU-marked cases, what may be called a " locular arrangement of the cells " may be seen, where clusters of eight or nine cells of lymphocytar aspect are noticed around a central lymphoblastic form of cell (Fig. 34). These clusters of cells are sometimes formed of cells with a mesolymphocytic character. Whether the chain of development is always in the same direction or not is doubtful. It is very probable that there is a circular line, or cycle of development, by which is meant that under various circumstances the lymphocytar ceU may give rise to a mesolymphocytar cell, and this to a genn-centre cell, while, on the other hand, the pulpar cell in its turn may give rise to a 9 130 Biology of the Blood-cells lymphoblastic or to a germ-centre type of cell. This view is ad- vanced by Pappenheim, and it is a conclusion which can be reached by anyone who has studied a large number of tissues containing lymphatic foUicles. In other words, it is an axiom, and the state- ment requires the name of no authority for its substantiation. It is another matter to ascertain under what conditions the return of the cycle takes place, or whether the word " return " expresses a mis- conception. Motion round a circle is neither advance nor return. Looking at the subject of lymphopoiesis in this manner, we see no difficulty in explaining where the mother cells come from. Whether they arise or not from connective-tissue elements (Ciaccioi3) under certain circumstances, such as after the injection of nucleinic acid or potassium iodide, is a matter of compara- tively little difficulty. As we shall see, in discussing the wandering cells of the body in general, there is always a phase in which the given cell appears as a connective-tissue cell. It is very likely that connective-tissue elements may fuse into a Plasmodium, become free, and appear as cells whose nucleus is large and whose cytoplasm appears as a rim — a statement put forward by the author just named. Further, we have the pulp as a source of mother cells, since the pulpar cell, as will be shown, presents morphological and other characters which point to some genetic connection with the follicular cells of the lymph-node or Malpighian body of the spleen. Discussion of these points is therefore deferred till the mono- cyte has been dealt with. Plate III shows a scheme of the develop- ment of the lymphocyte based on studies of lymphoid tissues. The development oj lymph-nodes themselves has been studied by Gulland, Saxer, Ketterer, Baum and Hille, Kling, Sabin, and others. ^^ According to these observers, the lymphatic vessels appear first and mesenchymal elements cluster around them later, forming intercommunicating ceU-columns which are ultimately vascularized from adjacent blood-channels. The mesen- chymal tissue pouches into the dilating lymphatic vessels, and thus gives rise to the appearance already described — ^that of the follicle being like an apple on a stalk. The circumfoUicular sinus is thus the deformed original lymphatic vessel. It is evident from a study of the adult lymph-node that some such process must have occurred during development. In passing, it may be noted that lymph-glands may disappear during adult life, being replaced by adipose tissue, and that adipose tissue may give rise to new lymph-nodes when occasion calls. The Lymphocyte of the Blood-stream 131 III.— THE LYMPHOCYTE OF THE BLOOD-STREAM. The lymphoid elements of the blood — ^Morphology of the lymphocyte — ^The differen- tial diagnosis of the lymphocyte — ^The functions of the lymphocjrte — Lympho- cytosis and lymphopenia — The nutrioid function — The adsorptoid function — Relation to phagocytosis — The chemistry of the lymphocyte ; of its azur granules — The comparative cytology of the lymphocyte. Having traced the development of the lymphoid cells up to the point of true lymphocyte formation, and having described the changes which take place within a lymphoid foUicle during the phases of metabolic activity, there is no difficulty in deciding upon the mode in which the lymphocyte reaches the circulating blood. A small proportion of these cells pEiss directly into the blood-channels; the majority are sucked out of the follicles into the juice canals of the connective tissues and thence into the lymphatic channels till they reach the thoracic ducts on either side. Those which are made in lymph-nodes pass into the efferent lymphatics, as shown by cell-counts in experimental animals. In all cases the bulk of the lymphocytes appear to reach the veins at the root of the neck. It is a noteworthy fact that all blood-cells reach the blood through venous blood. The Lymphoid Elements of the Blood-stream include several forms which it is convenient to tabulate at this point : — 1. Small lymphocytes, with their leucocytoid forms. 2. Medium-sized or mesolymphocytes. 3. Large mononuclear leucoc5rtes (monocytes), including transitional forms, and myeloic cells. 4. Primordial cells. 5. Sarcoma cells. The only members of this group which are normal to the circulating blood are the first, the second, and the large mononuclear leucocyte with its transitional form. If the other cells are found in a blood-film, they indicate the presence of disease. The Ust may be amplified in order to bring together many of the atypical forms which may be looked for in clinical work. The 132 Biology of the Blood-cells small lymphocytes may appear in dwarf form, or in amitosing forms; they may appear in the form of fatty degeneration (in acute lymphsemia, sub finem vUcb), in the form of the so-called Klein-Gumprecht shadows. The latter are the effect of cytolysis, and are specially numerous in acute lymphocytic and myeloic leukaemias. The large mononuclears or monocytes include : — Myeloic cells, derived from the bone-marrow (= leucoblasts) . (a). Non-granular myelocytar cells with oxyphile ceU-body. (6). Non-granular metamyelocytar cells with oxyphile cell-body. (c). Non-granular polynuclear leucocytes with oxyphile cell-body. InterfoUicular lymphadenoid cells, the ordinary large mononuclear leucocyte or splenocyte. Transitional leucocyte or splenocyte. The -primordial lymphoid cells include : — The large lymphocyte or macrolymphocyte (lymphoblast) with its senile and Rieder forms. This is met with in the blood in lymphsemia. The macrolymphoc5rte or myeloblast, or myelolymphocyte. This may appear in senile form. The micromyeloblast and its leucocytoid form are almost exactly the same morphologically as the small lymphocyte. The large Rieder leucocyte. Polynuclear leucoblasts (basophile non-granular cells with polymor- phous nucleus). Whether the sarcoma cell could be identified in the blood- stream remains to be seen. That it is possible to identify malignant cells in exudates has been established by the writer 28 some years ago, although, as with the identification of blood-ceUs, the personal factor is too great to allow stereotyped rules to be drawn up which shall guide the novice to a right diagnosis. The Morphological Characters of the Lymphocyte.* — Outer Form. — The cell has a diameter of 7"5 j^ on an average. The limits of variation are 5 and 10 ;". The shape of the cell is almost exactly sphericaLf The contour is regular and smooth.J * See Plate III., 6'; Plate IV. t Rosenthal considers that the living lymphocyte is not round ; it only assumes the spherical shape when dead or dying. X Specimens are sometimes seen in which the outline is jagged, and it has been supposed that : (i) Detached fragments of such spicules appear in blood-films as platelets ; (2) They are flagella (so-called Flemming's bodies). H. C. Ross believed that fiagella are detached from lymphocytes, and seriously put forward a suggestion that they might function as spermatozoa to other lymphoid cells in the circulation or elsewhere '. The Lymphocyte of the Blood-stream 133 The cell-body is small relative to the nucleus, and with the panoptic stain is of a bright but pale blue, showing a network with varjdng distinctness. The paraplasm is very abundant. Granules. — Granules are present, being often arranged into discrete clumps. They have been variously named azur, Schridde,* and Beckton granules. Possibly aU these forms are one and the same in nature (see below). Nucleus. — ^This is strictly spherical, and is large relatively to the cell. It is central in position in young cells, slightly excentric in old ones. The nuclear membrane is thick, the chromatin is trachychromatic in staining power, pachychromatic in texture. There is a well-marked perinuclear halo, and an astrosphere can sometimes be made out. If there be a nuclear dimple, the astro- sphere is over against this. Nucleolus. — ^There is generally one excentric metachromatically staining nucleolus. Occasionally more may be made out. Appearances with Ultra-violet Light. — The nuclear substance is only very slightly permeable to ultra-violet (magnesium and cad- mium) rays, and indeed is quite impermeable in some places, just as holds in the case of erythroblast nuclei (Grawitz^s). The ceU- body is never homogeneous, but is cloudy or flaky owing to the presence of irregularly distributed dusky areas. Their distribution, therefore, demonstrates that the shading does not correspond to nodal intersections of spongioplasm. A few very fine and coarse granules can also be detected — these are identical with the azur granules. Appearances with the Ultra-microscope. — This method of study shows the middle zone of the cell to be small (compare with the appearance of the neutrophile leucocyte). Jagic claims that the azur granules are visible. The lymphocyte of chronic lymphatic leukasmia has a very narrow cell-body ; the nucleus is almost " naked." The nucleus is paler and the chromatin looser in texture than in the true Ijmiphocyte. Azur granules are never present. The size of these cells is very variable, and there is no constant numerical relation between the small and large forms. Each case presents its own peculiarities. The lymphocyte of the tissue is described in the fourth section. * The Schridde granules are perinuclear fuchsinophile granules. 134 Biology of the Blood-cells EXPLANATION OF PLATE IV. 1. — Lymphocyte with minimal cytoplasm. 2. — Normal lymphocyte. 3. — Leuco- cytoid lymphocyte. 4. — Lymphocyte with reniform nucleus. 5. — Mesolymphocyte. 6. — Dwarf lymphocyte. 7. — Lymphocyte showing mitosis. 8. — Myelolymphocyte. 9. — Juvenile large mononuclear. 10. — Normal monocyte. 11. — ^Transitional cell. 12. — Leucocytoid large mononuclear. 13. — Leucoblastic monocyte. 14. — Myeloic mono- cyte without azur granules. 1 5. — Leucocytoid myeloic monocyte. 1 6. — Myeloic monocyte with indented nucleus. 1 7. — Polynuclear leucoblast. 1 8. — Metamyelocyte. 1 9. — Normal polynuclear leucocyte. 20. — Dwarf polynuclear leucocyte. 21. — Basophile polynuclear (granular neutrophile leucocyte. 22. — Non-granular polynuclear neutrophile leucocyte. 23. — Giant leucocyte. 24. — Leucoblast. 26. — Promyelocyte. 26. — Dwarf promyelocyte. 27. — Basophile promyelocyte. 28. — Polynuclear promyelocyte. 29. — Myelocyte. 30. — Dwarf myelocyte. 31 . — Non-granular myelocyte. 32. — Rieder form of myelyte. 33. — Myelocyte with mitosis (Klein, Fol. haem. a. p. 4?5). 34. — Metamyelocyte. 35. — Non- granular metamyelocyte. 36. — Basophile metamyelocyte. 37. — Lymphoidocyte. 38. — Leucocytoid lymphoidocyte. 39. — Dwarf or micro-lymphoidocyte. 40. — Rieder lymphoido- cyte. 41. — Plasma-cell lymphoidocyte. 42. — Sternberg's leuco-sarcoma cell (Klein, ibid.). 43. — Juvenile macrolymphocyte (Klein, ibid.). 44. — Normal macrolymphocyte. 45. — Senile macrolymphocyte. 46. — Lymphoid hsemoblast. 47. — Hybrid eosinophile-mast cell. PLATE IV. MONOMUCLEAR AND CERTAIN OTHER BLOOD-CELLS Juvenile Adult I)\vare PArinii.Dr.icAL dk Akekkak ,^- l^ w 43 • ;# f v^ 12 25 ^-'^.r- 37 IB ^*: « /(>'!9 14 '■ o><-'- 15 17 27 32 33 «/ # Z^^' 47 Yj/og3' 0/ Blood-cdU The Lymphocyte of the Blood-stream 135 The Differential Diagnosis of the Lymphocyte. — The diagnosis of lymphocytes in blood-films is difficult owing to the lack of tmiformity of description of the various lymphoid cells that can be met with in the circulating blood. Not only is it necessary to correctly name these cells, but the various degenerative forms must be recognized and recorded. The classification of mononuclear cells into small lymphocytes, large lymphocytes, hyaline and transitional cells, as is customary in much of the literature, is inadequate, and though Pappenheim's panoptic stain is advisable for much of the work of differentiation, the cell-forms can be fairly well distinguished by the ordinary staining methods in vogue at the present day (e.g., Leishman-Wright). Pappenheim's staining method is as follows : — Air-dried film-stain with Jenner's stain under cover for three minutes by the watch. Add five to ten drops of distilled water (same volume as the stain previously used), without rinsing ; drain (do not rinse) ; stain with freshly-prepared dilution of Giemsa, i-io, for twelve minutes ; thoroughly wash with distilled water ; dry without heat. The cells which may simulate the lymphocyte are as follows (see Plate IV.) :— 1. Leucocytoid Lymphocyte. — ^This cell resembles the ordinary lymphocyte, save that the cell-body is decidedly larger relative to the nucleus, the latter being excentric, and absolutely smaller than in the true lymphocyte. This cell is merely an older form of lymphocyte. 2. Lymphocyte with Reniform Nucleus. — ^This cell is exactly like an ordinary lymphocyte, but the nucleus is indented or reniform. The cytoplasm is paler in the vicinity of this dimple. Both these forms are popularly classed along with the lympho- cyte in differential counts. 3. Mesolymphocyte. — The characters of this cell have been given above. The nuclear structure is similar to that of an ordinary lymphocyte. The chief difference between this and the micro- lymphocyte is one of size. Sometimes the nuclear character is more defined in this type of cell, polygonal areas of deeper-stained material being present, the angles being drawn out into filamentous structures which interlace. 136 Biology of the Blood-cells 4. Juvenile lymphocytes are similar to microlymphocytes, but cell-body is practically indistinguishable. These are sometimes called " naked " lymphocytes. 5. Dwarf lymphocytes have already been referred to. The descriptive term is sufficient to serve for their differentiation. 6. Lymphocytes with nuclei in a state of amitotic division. It is questionable where these belong. Their nuclear characters are sufficiently distinctive. 7. Microlymphoidocyte. — This cell resembles the mother cell or lymphoidocyte in its nuclear markings and general characters, but is hardly larger than the average lymphocyte. 8. Leucocytoid Microlymphoidocyte. — This cell is also distin- guished by the characteristic nuclear markings (as of the lymphoido- cyte). But the cell-body is relatively more abundant. 9. Dwarf Lymphoidocyte. — This is smaller than 7, but otherwise identical in characters. 10. Rieder Cell. — ^This type of ceU has already been fully described. Sometimes these are very smaU, but the polymor- phism of the nucleus is sufficient for diagnosis. The only real difficulty might lie in distinguishing it from an amitosing lymphocyte. 11. Neutrophile Pseudo-lymphocyte (Ehrlich). — Myeloic granulo- potent pseudo-lymphocyte of Pappenheim, or myelolymphocyte. This cell is as large as a lymphocyte, the cytoplasm is narrow, and the nucleus is rich in chromatin. The difference from an ordinary lymphocyte lies in the presence in the pseudo-lymphocyte of " myeloic " azur or of neutrophilic grajiules. Ehrlich considered that they were small pol3muclears, but Pappenheim considers that they represent a metaplastic change in the lymphocyte. It is met with in pleural exudates. 12. Lymphoid Hcemohlast. — The characters of this cell, and the differential diagnosis, have been considered on pp. 60, 64. 13. Plasma or Irritation Cells. — These wiU be considered in Chapter VI. The main characters briefly consist in marked baso- phiha of the peripheral parts of the cell-body, well-marked peri- nuclear halo and astrosphere, and vacuolation of the cytoplasm. 14. Aberrant mononuclear forms of the neutrophile series The Lymphocyte of the Blood-stream 137 require to be borne in mind in differentiating the " lymphoid elements " of the blood-film (Chapter V.). 15. Degenerative Forms. — Vacuolation of the cell-body, feeble- ness of staining of nucleus, Hi-definition of outhne of the cell (indica- tive of cytolysis), or the presence of foreign bodies within the cells, as well as shadow forms, require to be noted. 16. Tumour Cells. — As already mentioned, we have yet to leam whether true sarcoma or carcinoma cells can be identified in a blood-film. 17. Intermediate forms between some of these types cannot be distinguished, and it would be difficult to assign satisfactory names to them. The following " couples " are very much alike : the ordinary micro- lymphocyte and the microlymphoidoc3rte, the macrolymphocyte with narrow cell-body and the lymphoidocyte, the leucocytoid mesolymphoc3rte and the leucocytoid myelolymphocyte. Further examples of similar couples, which belong reaUy to the next chapter, are : monocyte with reniform nucleus and leucoblast with reniform nucleus ; monocjrte with azur granules and leucoblast with azur granules. A promyelocyte with neutrophile granules may simulate the latter. From a study of these cell forms we find that the accepted " small lymphocyte " may be one of these ; the true l3anphocyte, or microl3anphocyte, numbers i, 2, 3, 4, 5, 6, 7, 9, 11, 12, also leucosarcoma cells and juvenile monocytes. The accepted large lymphocyte is really not in this series at all. The accepted hyaline cell is one of these ; i, 3, 8, 14, or monocytes. The Functions of the LYmphocYte. — A careful study of the literature bears out the conclusion derived from the perusal of text-books of physiology — that our knowledge upon the functions of the lymphocyte is almost nil. The difficulties of direct observa- tion are extreme, and though a number of experiments on living lymphocytes have been published by H. C. Ross, the deductions to be made therefrom are of uncertain value. A study of the causes of lymphocytosis and lymphopenia of the various tissues in different physiological conditions should afford some clue to the facts, but unfortunately the reports in the literature invariably fail to distin- guish between the true lymphocyte and the leucocytoid and large 138 Biology of the Blood-cells mononuclear lymphoid cell forms. The practice of gathering all lymphoid cells under one head is almost invariable, so that the whole subject must be investigated de novo, with much greater care and detail. Until this is done, the inferences to be drawn from a study of certain chemical considerations, and from investigations upon metaplasias in tissues, must remain our sole basis of know- ledge upon the fimctions of the l3anphocyte. The Causes of Lymphocytosis. — In the circulation, the lymphocyte normally constitutes about 25 per cent of the total white-cell count. In other words, there are about 2000 per cubic millimetre. In embryonic life, and in the infant, these cells number up to about 70 per cent of the total white cells. The following are some of the possible variations from the normal : (i) The total numbers may be increased without altera- tion of the cell formula (absolute lymphocjrtosis) ; (2) The total numbers may be increased and the relative proportions to the other cells be also increased (absolute + relative lymphocytosis ; (3) The relative proportions of the lymphoc3rtes to the other cells may be increased, and yet the total count be normal (relative l5anphocytosis) ; (4) The relative proportions of the lymphocytes to the other cells may be increased, but the total count be diminished (hyper-hypol3Tiiphocytosis) ; (5) The total count may be diminished while the proportions are maintained (lymphopenia) ; (6) The total count may be diminished and the proportions diminished (absolute lymphopenia). Absolute l5Tnphocytosis occurs in a number of conditions : (i) During the digestion of carbohydrates (increased up to 3000 per c.mm., according to Keuthen) ; (2) During starvation or periods of hunger^o : (3) In the course of acute fevers (typhoid, after the first week, measles, at the end of scarlet fever, during the lysis of pneumonia, in small-pox, in the acute diarrhceal diseases of infancy, and in bronchopneumonia) ; (4) After severe injury to the spleen (Gross). Relative lymphocytosis occurs (a) in certain chronic infections : tuberculosis, secondary and congenital syphilis, and the chlorotic type of syphilis) ; (b) in pernicious anaemia, chlorosis, scurvy, and haemophilia ; (c) in some cases of Graves' disease^i ; {d) in malnutrition ; in rickets ; (e) after splenectomy in animals. The Lymphocyte of the Blood-stream 139 Frogs react to bacterial infection by well-marked lympho- cytosis just as warm-blooded animals react by polynucleosis. Galambos"^ gives a long list, collected from the literature, of causes of lymphocytosis, from which one concludes that there is not a disease in which this condition of the blood may not arise. Such diseases may be quoted (in addition to the above) as mumps, malaria, chronic enteritis, epilepsy, tabes, achylia gastrica, acute alcoholism, asthma (inter-paroxysmal), osteo- malacia, acromegaly, Addison's disease, etc., etc. (forty-eight conditions are quoted in all !). This indicates that the study of diseases in this manner is of little value. We require to know the physiological conditions obtaining. Experimentally, lymphocytosis is induced by injections of tuber- culin, pilocarpine (Roussa), muscarin, barium chloride (Harvey^^), thyroid extract, staphylotoxin, etc. Bergel^s found that mice and frogs were readily influenced by such agencies. He concludes that any infective agent of lipoid character will attract lymphocytes (e.g., tubercles). Iodine (Loebe and Michaud^e) and mercury (Baldoni37) are taken up by them. Lymphopenia occurs during the digestion of fats (Keuthe^i) and proteids, in some cases of visceral and pulmonary tuberculosis,* and in cases where tumours block the lymph-paths (e.g., lympho- sarcoma). It will be noticed that lymphatic leukaemia is not quoted as a cause of l)rmphocytosis. Since the lymphocytes in this disease are not true micro- Isnnphocytes, we prefer to place this with increase in the numbers of primordial cells. In the above lists we have been unable to draw a distinction between the finer varieties of lymphocjrtosis and lymphopenia, owing to lack of data. The Nutrioid Function of Lymphocytes. — This has been studied by certain workers, with equivocal resiilts. The relation between lymphocytes, in the blood-stream and digestion suggests that these cells have something to do with food-absorption. Pavy, probably quoting Pohl, considered that they took up proteid matter from the surface of the villi, or even in the stroma of the villi, incorporated it into their own cell-bodies, and, subsequently reaching distant parts of the body, finally dissolved in the tissues, thus bringing the latter a readily assimilable form of proteid. * Compare with the fact that lymphocytosis in a puncture-fluid indicates tuberculous disease when met with in pleural or abdominal exudations. 140 Biology of the Blood-cells Erdelyss found that in rats fed on meat, the chief cells in the villi were granular — ^when fed on potato, the chief cells were lympho- cytes — and when fed on bacon-fat, the chief ceUs were lymphocytes, but a few granular cells also appeared. In starvation, few granular cells could be found. Grawitz, commenting on these findings, concluded that all kinds of cells are made in the intestinal wall, and that lymphocytes play an important part in the absorption of sugar. Under the influence of meat or mixed diet, lympho- cytes would turn into polynuclear leucocytes. Goodall, Gulland, and Paton,3 9 in experiments on digestion leucoc5rtosis, concluded that the increase was the result of activity — not in the intestinal wall, or spleen or mesenteric glands, but in the bone-marrow. They decided that the thoracic duct was a very unimportant source of lymphocytes, and quoted Crescenzi's*" experiments in support of this view. Whereas the latter observer considered that the explanation of lymphocytosis after splenectgmy and fistula- formation of the thoracic duct lay in a direct passage of the lymphocytes into the blood-stream, the quoted Enghsh observers interpret it as a proof that the marrow makes lymphocytes in adequate numbers all the time. The present writer, however, on the basis of observations on hundreds of lymph-nodes, agrees with Crescenzi in believing that many more lymphocytes enter the blood-stream direct than is believed, and doubts whether the bone- marrow is adequate to make hundreds of millions of red cells, of leucocytes, and also millions of lymphocytes every day without being always " leucoblastic." Further, if the lymph-nodes are not the chief source of l5rmphocytes, why should there be universal tissue-lymphocyte factories through the body ? The observation that the blood in the intestinal veins is richer in white cells than that in the mesenteric arteries, indicates that the intestinal tract does have something to do with the formation of these cells, and that they have something to do with nutritional processes. The presence of peptids in the small intesttae may act as a stimulus to temporary hyperactivity of the lymphoid tissues there. The lymphocytes so formed may exude into the bowel lumen, devour deleterious products (Burian and Schur^oa), and be shed The Lymphocyte of the Blood-stream 141 with fsecal matter, or break up food-matter further, and carry it into the villus* and so into the blood-stream (via the lacteal, or otherwise). Whether they take up carbohydrate or fat is not known. Sirensky^s found lymphocytosis was related to carbo- hydrate food, while polynucleosis follows proteid food. Asher considers that lymphocytes have to do with conversion of the products of dis-assimilation brought to the lymph-nodes. {See also under " Fate of the lymphocyte.") Adsorptoid Function. — Whether lymphocytes exert a bacteri- cidal function or not is not quite clear. The large mononuclears are well-known phagocytes, but, as insisted in previous pages, we draw a very sharp distinction between the microlymphocyte and other so-called l5nnphocytes. From the writer's observations, the method of removing bacteria adopted by lymphocytes is largely one of adsorption of the microbe in response to some imknown force acting between the two cells, rather than one of true phago- cytosis. Pfeiffer and Wassermann considered that experimental evidence was in favour of lymphocytes possessing a bactericidal action ; Wanters argued against this. In favour of such a view is Bartel's finding that tubercle bacilli exposed to lymphocytes lose their virulence. Bearing indirectly on this subject is the question of whether these cells possess amoeboid power or no. Amceboid Properties. — Levaditi, quoting Israel, considers that the observations made by Proscher, Wolff and Arpad, Torday and Schwartz, leave much to be desired. He considers it far from settled that lymphocytes manifest active diapedesis. It is true that the reason for the widespread distribution of lymphocytes in inflammatory exudates may lie in local production much more than in amoeboid movement. The Chemistry of the Lymphocyte. — Chemical analysis cannot be applied accurately to the study of the lymphocyte as an individual. Percentage analyses have been determined for the lymph nodes as a whole, and suffer from the unavoidable circum- stance that all manner of cells are estimated together. The most recent account of the subject from this point of view is that by * MacCallum, of Toronto. 142 Biology of the Blood-cells Gerhartz.4s The lymph-node, according to observations quoted by this author, contains 8 per cent nucleoproteid, or 0*83 per cent phosphorus. Alcoholic extracts contain protagon, inosite, lecithin, cholesterin, some sarcolactic acid, xanthin bodies, leucin, collagen, reticulin, and elastin. These findings are common to practically every other tissue in the body. Every cell contains Upoid sub- stances, since Ufe is impossible without them ; every nucleus gives rise to xanthin bodies as long as it remains capable of mitosis, and every interstitial tissue contains some collagen, etc. Pappenheim« considers that the pathological lymphocyte poured out in Hodgkin's disease produces a " hypemomic secretion " of lipase which acts on red-cell lipoid like pancreas steapsin, and so causes the anaemia. In a paper on pseudo-leukaemia, by Tschistowitsch,42 it is shown that the Ijnnphocytes were enormously increased, and that fever was correspondingly conspicuous. Nucleases act on nucleoproteid or histone of the follicle cell to make nucleic acid (= phosphoric acid, purins, etc.) plus albumin or histone. The latter may play some necessary part in mitosis (Ciaccioi3). The findings of arginase in lymph-nodes, by Cohnheim,** is of interest ; the amount is small. Oxydase and paroxydase (Fischel^^) are also found, according to a few observers. In short, as regards ferments, we expect to find each in varying quantity according to the proportions of cells within the lymph-node, whose ferment content is known. Lymphocytes, for instance, contain lipase, as they have the power of dissolving waxy material (Bergel^^), and their cell-bodies accordingly contain no fat.^^a Autolytic ferments are not present — a distinction from the neutrophile leucocyte. Working with a neutral saturated aqueous solution of malachite green, Kronberger found that certain of the small lymphocytes of the blood (digestion-lymphocytes) are readily recognizable by the intense emerald-green reaction of the nucleus. From this observa- tion and theoretical dye-chemistry considerations, it was concluded that the nucleus contained much nucleo-albumin, which is not present noticeably in the neutrophile pseudo-lymphocytes. Com- paring these findings with those obtained by means of methyl-green- The Lymphocyte of the Blood-stream 143 p37ronin, Pappenheim considered that the lymphocyte nucleus does not consist of pure nucleic acid, is less rich in certain purins than are the poljuuclear leucocytes, and is richer in basic histone (nucleo- histone). Thus, methyl-green-p3nronin give a blue-violet with resting nuclei, green with mitosing nuclei and spermatozoon-heads ; further, preliminary mordaiiting with alum gives different results — l3nnphocytes staining greenish-grey, while pol5muclear leucoc3rtes stain more reddish-violet, indicating that after mordanting the lymphocyte nucleus has a more alkaline reaction than the neutro- phile. The Chemistry of the Lymphocyte Granules. — The granules of the lymphocyte are the so-called azur granules. They stain with azur dyes* (Romanowsky, Giemsa), as discovered by Michaelis and Wolff-Eisner*'' in 1902. These bodies occur in true lympho- C5d;es, in the large lymphoid " monocytes " of normal blood, in myelolymphocytes, in l3miphoblastic macrolymphocytes, in l5anphoid leucoblasts, occasionally in neutrophUe promyelocytes, but not in lymphoid erythroblasts, or in mature plasma cells (Pappenheim* 8). The granule, as seen in the lymphatic series of lymphoid cells, is small, roimd, of scarlet-red colour, and appears sparsely scattered through the cell-body. In the guinea-pig these granules are coarser and more numerous. They increase in number as the ceU becomes older. It will be seen later that there is another form of azur granule, the myeloic azur granule. This is very similar in tint to the neutrophile granule (so-called immature stage of neutrophile granule), being of a bluish purple colour, and scattered diffusely through the cell in considerable numbers. These granules vary much in size, being sometimes very fine, at other times very coarse, and even simulate flocculent precipitates within the cell-body. It will be shown later that Pappenheim believes these myeloic granulations to be derived from part of the nuclear matter, and not from the spongioplasm. The azur granulation is not specific. It is evident that examples of lymphoc5rtes may occur which are devoid of azur granules. Such cells are still classed as lymphocytes. An eosino- • Yet not by azur alone. The granules are not azurophile, as they only stain in mixtures of methylene blue, eosin, and azur.'' 144 Biology of the Blood-cells phile, on the other hand, necessarily contains eosinophile granules. In other words, the lymphocyte granule is not regarded as evidence of differentiation of a lymphoid cell. Views as to the Nature of Azur Granulation. — 1. That they are artefact. They may be the result of fixation ; precipitation of proteins (Grawitz), or they may be the nodal intersections of the cytoplasmic reticulum (Gulland). This view is excluded by the appearance of the cells with ultra-violet hght.* 2. That they are definite entities — («). That they are secreted or excreted dead material. In favour of this view are the following points : (i) that they are commoner in older cells, leucocytoid lymphocytes,t (ii) that similar bodies occur in the large mononuclears of guinea-pigs. Here they are definitely secretory (Cesaris-Demel). Against the view is Levaditi's observation that the small lymphocytes of the anthropo- morphic apes are as rich in granulation as are the large forms. If dead, are they lipoid in nature ? They stain with vital stains I like the Kurloff bodies in large mononuclear leucocytes, and also stain metachromatically. On the other hand, they are not the same as Schridde granules, since (i) they are not confined to the perinuclear zone, (ii) are of different shape, (iii) are in- constant (Turk, Pappenheim), (iv) are visible with dark-ground illumination (Jagic^^), and (v) also with ultra-violet light (Grawitz). (b). That they are living. — On this view they may either consti- tute a preliminary phase of neutrophilic granulation, oi may precede the latter without being converted into it. In either case they may be assumed to be of ferment character (Naegeli, Hynek, Grawitz, Weidenreich). Blumenthal considers them to be precursors of other granules besides neutrophilic granules. The arguments pro and con in this case are analogous to those brought forward under the heading of monocyte granulation {see p. 185), but they are not very cogent. If they are not directly converted into neutrophilic granules. ' A similar view has been expressed regarding the neutrophilic granule of leucocytes. These granules are visible with ultra-violet light. J agio states that he has seen them with dark-ground illumination. t Ehrlich surmised that they were a sign of old age. % According to Ferrata they are the same as the vital-staining plasmosomes. The Lymphocyte of the Blood-stream 145 they must be looked on as a preliminary deposit in the immature cell, indicative of a cytometaplastic change proceeding within it. The neutrophile granules eventually appear, side by side with the azur, and ultimately outshadow them when the myeloblastic change is complete. This view, advanced by Pappenheim.^s depends for its proof upon the subtleties of microchemical staining reactions. He holds that these azur granules are a product of secretion, and are only temporarily contained within the cell. The true granula- tion is a bearer of cell-function (Pappenheim-Ferrata, igii^o). If we accept the view that neutrophilia is a specific property and that azur-granules are not specific, then we should incline to believe that the two forms of intracellular material were quite distinct from first to last, and not regard the difference to be merely that between child and adult. The Schridde Granule. — This form of granule (really an Altmann granule) is always present in every lymphocyte, is invisible both in dark-ground illumination and in ultra-violet light, and is not specific (Kleinsi). Meves^a believes the Schridde granule to be a chondriosome. The nature of this granule is stiU sub judice. The only certain feature about it is that it is not characteristic of a myeloblastic cell. It is very probable that Schridde's granules are identical with Altmann's and are a necessary constituent of every cell. Naturally they are more common in some than others, just as every cell does not contain the same amount of nucleic acid. There can be no question but that this granule (which Grawitz believed to be really not a true granule at aU) is concentrated lipoid matter. This being so, it is evident that Beckton's claim that Altmann granules in sarcoma cells or carcinoma cells are diagnostic, is made regardless of the necessities of C5rto-chemistry. On the other hand, it is possible that abundance or paucity of lipoid granules may be distinguishing factors between cells. Comparative Cytology of the Lymphocyte. — Broadly speaking, the lower the vertebrate scale be descended, the more abundant are the lympho- cytes in the blood. When studied closely, however, it is evident, from the researches of Werzberg, that while the lowest vertebrates tend to have a preponderance of mononuclears in the blood, all such cells do not belong to the category of the human lymphocyte. In many instances, the resem- blance to the large mononuclear is more striking, while in others the lymphoid cell is definitely lymphoidocytar, as stated in Chapter I. On the other hand, it is not difficult rapidly to survey the lymphocyte through the animal series, because the morphology of this cell remains very constant. The 10 146 Biology of the Blood-cells ordinary small round basophile lymphocyte is always accompanied by the form with relatively abundant cytoplasm and possibly indented nucleus (the leucocytoid form) ; and in all cases the characters of the cytoplasm and nucleus are the same in the leucocytoid form (save for the feature men- tioned) as in the microlymphocyte form. The matter of greatest interest, however, is the fact that many of the authorities on comparative cytology find themselves forced to the conclusion that in amphibia and reptilia the lymphocyte is actually the parent of the polynuclear leucocyte (or what serves for a " neutrophile " in such animals), the transitional stage being the large mononuclear leucocyte and the transi- tional cell (Freidsohn52■ remams so 4. Is poly (myelo) blast 1 >■ becomes myeloic cell ■« 5. Becomes " eosinoid " -^ polynuclear eosinophile of the tissue 6. ,, micromyeloblast -^ ,, neutrophile ,, -^■ 7. ,, " plasmoid "-> plasma cell (see " Chart showing fate of plasma 8. Undergoes cytorrhexis. [cell ") 155 CHAPTER IV. ON THE LARGE MONONUCLEAR LEUCOCYTE. Section I. — On the Structure of the Pulpar Tissue : The pulp- cord is the second physiological unit of the spleen and lymph-node : its structure — ^The giant cell of the spleen — Metabolic changes in the pulpar tissue — Functions of the spleen— The accessory pulp-cell factories : the accessory spleen ; the hsemolymph-glands. Section II. — On the Large Mononuclear Leucocyte of the Blood-stream : The meaning of the terms : large mononuclear leuco- cyte, splenocyte, monocyte, lympholeucocyte — Pappenheim's monocyte : its morphology ; contrast between the two varieties of monocyte — The morphological characters of the large mononuclear leucocyte : the^ secretory vacuoles — ^The variants : the lymphocytoid, transitional, miniature, and giant forms — The differential diagnosis — The theories as to the origin of the large mononuclear leucocyte of the blood-stream— (myeloid, lymphoid, endothelial) — The birth of the cell into the blood- stream — The functions of the large mononuclear : numerical variations — Chemical characters. — The azur granules. — Comparative cytology — The fate of the large mononuclear leucocyte. — Transitional cell ; degener- ative changes ; irritation changes ; reversion to tissue-spaces. Section III. — The Pulpar Cell and its Cytoplasias : The morphology of the pulpar cell — It is a multi-potential cell. — Its relation to the lymphoid follicles and to myeloid metaplasia. — Genetic inter- relations. — Chart representing these, and summarizing the essential features of the biology of the cells referred to in this and the preceding chapter. 156 Biology of the Blood-cells I.— ON THE STRUCTURE OF THE PULPAR TISSUE. The pulp-cord is the second physiological unit of the spleen and lymph-node : its structure— The giant cell of the spleen — ^Metabolic changes in the pulpar tissue — Functions of the spleen — The accessory pulp-cell factories: the accessory spleen ; the hasmolymph-glands. IT has been pointed out that the lymph-nodes resemble the spleen in structure to the extent that both are made up of follicular and pulpar tissue. The former is regarded as an important source of blood-lymphocytes, and is known to be a factory for tissue-lymphocytes. The pulpar tissues, on the other hand, are concerned in some obscure way with the formation of all the other lymphoid cells which may be encountered in the blood-stream, and of many forms met with in the tissues in question. Speaking generally, it matters little whether a lymphoid follicle is in the spleen, in a lymph-node, or elsewhere. Similarly, several of the essential features of the pulpar tissue are equally well observed whether we deal with spleen or lymph-node. The anatomical position of this tissue is to a certain extent a matter of indifference, and although there is usually sufficient character about the lymph-node pulp to enable its identification from splenic pulp, there are occasions when it would be extremely difficult to decide to which organ the tissue belongs. Thus, Fig. 35 shows a preparation of a lymph-node which bears a remarkable resemblance to splenic tissue. Such an appearance might be regarded as patho- logical, and yet it is found, in lumbar glands especially, under circumstances which can hardly be placed with any given morbid condition. It is only during recent years that the reality of such an entity as pulpar tissue has come to be recognized, with the result that a far more satisfactory view-point of the physiology and pathology of lymph-nodes and spleen is now possible. We therefore emphasize the similarity of architecture which obtains in the node and the spleen-pulp, and the close family resemblance exlubited by the cellular inhabitants of these tissues. What may be spoken of as *■ . . . a preparation of lymph-node which bears a remarkable resemblance to splenic tissue " (p. 156) Fii:. 35- — Splendid jMetaplasia of I,v:\iph-xode. Notice the lack of differentiation. A vascular channel traverses the field near its centre. The lymphoid cells vary in size and in staining reaction. (Oc. 6, Obj. 4 mm.). " The ]ni]p-cord, when cut across, is found to contain a sm-ill central vascular channel, enveloi)^:^ b\' a complete sheath of tissue" (p. i,S7). Fi". ^6. Transverse Section of a Ptilp-cord. Notice the central ring, the outline of the vascular chinners the outer ring markin*; o.*^ the perivascular sheath filled with " free floatincj cells, hemmed in bv' a delicate meshwork of reticular tissue." The peripheral clear zone in the photograph represenls- tiie h-mp'-iatic channel. ,,. ' o ^ ■ v, ■ (Oc. 8, Zeiss Oil-nnniersion}. "... blood-channels whose walls stand out ^-er}- conspicuously" (p. 159). FfL.'. 37.^The photograph shows two fragments of trabecule (vertical) and a number of elongated spaces marked out by the dark nuclei of endothelial cells. The intervening cells constitute the splenic ■[)ulp tissue. (Oc. 4, Zeiss Apochrom. 4 mm.l. " In cases of fibrosis of the pulp . . . the cords are found to be very rich in fibroblastic cell-forms " p. 159). Fis,. 38. — Splenic Pulp Tissue, showing Fibrosis. (.7) spindle-shaped fibre-cells in the pulp cords ; {b) venous channels ; (c ) endothelial cells lining same. {Oc. 4, Obj. 4 mm.). The Structure of the Pulpar Tissue 157 the splenoblastic line of development finds its theatre of action in the pulpar tissue, and its position in the anatomy is of secondary- importance. This conception gives us a ready explanation for the possibility of harmless removal of the spleen. The spleen and lymph-node have been seen to contain, as a unit of the lymphocyte-factories, the lymphoid foUicle ; they also contain a second unit, the pulp cord, which appertains to the manufacture of large mononuclear cells. The two histological organs or units are closely inter-related, and are really mutually interdependent, as shown by a study of the spleen under every conceivable condition. The Structure of a Pulp-cord. — In the lymph-node, it is easily ascertained that the pulp tissue is made up of a number of similar structures, forming an anastomosing network. These structures are called pulp-cords, and are best understood by reducing them to a mental picture of any one individual cord, no matter how minute it may be. Such a pulp-cord is shown in cross section in Fig. 36, and a careful study of such a field provides one with all the data necessary for the comprehension of the various cytometa- plastic changes to which lymphatic pulp is liable. Some of the cytological details are more clearly shown in the fragment repre- sented on Plate I. The pulp-cord, when cut across, is found to contain a small central vascular channel, enveloped by a complete sheath of tissue. This sheath contains many forms of free-floating cells, hemmed in by a delicate mesh-work of reticular tissue, whose texture is loose near the capillary, but becomes increasingly dense as one passes towards the periphery, and there forms a veil-like membrane demar- cating the pulp-cord from the surrounding lymphatic sinus. At the intersections of some of the trabeculse lie the reticular cells, whose nuclei are very prominent against the slender plate-like forms of the cell-bodies. Projecting from the capillary are a few adventitial cells, whose morphology is not always easily differen- tiated from that of the reticular cells. Indeed, careful focussing often demonstrates that their cytoplasm runs out into branching processes which blend with similar ones from the reticular cells, and in that way forms a kind of syncytial mass pervading the whole of 158 Biology of the Blood-cells the pulp-cord system. Close observation of the photograph will further reveal one or two gaps (exposed by optical section) in the outer sheath, giving free communication with the lymph-sinus beyond, so that the cells creeping amongst the reticulations of the cord can find exit into the lymphatic channels. The hall-mark of this pulpar tissue is the pulpar cell, whose morphological characters, expressed in an impressionist manner, vary from lymphoidocytar through macrolymphocytar to splenoidocytar, mono'cytar, and plasmoid forms. Not only does such a cell occur in the pulp-cord itself, but it will also be found to he in the pericordal lymphatic channels. The close relation between pulpar tissue and venous channels is more clearly shown in the spleen than in the lymph-node, while the splenic pulp does not show lymphatic channels in the conspicuous manner described for the lymphatic pulp-cord. While in the latter we pass from central blood-vessel through pulpar tissue to lymph- space and on to the main efferent trunk, in the spleen we pass from capillary through pulpar tissue back to capillary {Plate V). The sub-divisions of the splenic artery run to the respective compart- ments of the spleen, and break up into capillary channels, which rapidly lose a tubular character owing to the appearance of defects in their walls (elongated clefts). The lining cells of the capillary are narrow and elongated, the nucleus projecting strongly into the lumen, though covered by a film of cytoplasmic material (Mangubi- Kudrjavtzewai). A central and two lateral fibrils traverse the cell- body, whUe circular fibrils are let in on the basal surface of the cell. Protoplasmic thickenings called basal plates occur at the cell-edges, and give rise, according to Mollier,^ to a sjmcytial formation — the appearance of discrete endothelium usually seen in autopsy material being really artefact. The spaces between these branching cells constitute the meshwork of the pulp, so that the blood is really circulating amongst the cell-constituents of the pulpar tissue. Where the vascular channels can be distinguished, however, it is possible to differentiate pulp-cords by the closer network of connec- tive tissue which permeates them. The more rapidly-flowing blood runs on each side of the sponge-work of the pulp-cord, while slowly- flowing blood gently bathes the constituent cells on its way to the 6 '^ i*** yy ^ .^ l^' (^- ^J *^ ^' iJ- /?f^ J/^i d^ . % • K,' •kJ -:0 ^^ « 0^ Q 1 ^^ |'\ V-, '^ w W *.t e,, f' ,' V '?- ^' # <>. V \ r ^^^Q h^^t .f.^: ,€' _^ Op /- i^^ The Structure of the Pulpar Tissue 159 channels on either side. Fig. 37 shows a low-power view of the blood-channels whose walls stand out very conspicuously owing to the deep-staining property of the lining endothelium, and although cord-tissue does not always intervene, fragments of loose tissue can be made out here and there, in which blood-cells are intermingling with pulpar cells, exactly as in the lymph-node. In cases of fibrosis of the pulp, such as is shown in Fig. 38, the cords are found to be very rich in fibroblastic cell-forms, and the blood-cells are hardly noticed. The scene of action of the drama which is taking place amongst the cellular inhabitants of the spleen is best fixed in the mind by confining oneself to the intervascular reticular tissue and the adjacent capiUary wall, and has been depicted in Plate V under a very high magnification, in order to make the difficult subject of spleen histology more clear. The drawing shows a vascular channel traversing the field in a horizontal direction, and communicating with another channel coming from above by a narrow opening through which a couple of red cells are passing. Below, it presents a wide opening giving access to the small bay-like terminal of a third channel. Between these various blood-vessels are strands of tissue — the pulp-cords — and these are seen to be made up of a loose fibrillar connective tissue whose meshes support several types of ceU. The endothelium lining the main channel is only broken in one spot (to the right) by the passage of a lymphocyte through it, but the by-channels show many gaps in their endothelium, thus allowing free entry or exit to the various cells.* We must now picture to ourselves the appearance of this tissue in the living state. If we could be transformed into a red ceU, and f oUow its course through any of the labyrinthine passages, we should notice that the surface of their walls was curiously irregular, owing to the excessive prominence of the nuclei, which are apparently quite naked. In the main channel we should be moving at a con- siderable speed, but we should be able to linger a little in the side- paths, and observe the stni greater irregularity of their sides and * In the original specimen, the pulp-cords are actually occupied by numbers of red blood-cells, which have percolated through such apertures, but they have been omitted from the drawing for the sake of clearness. 160 Biology of the Blood-cells floor, the myriad recesses into which one might retire, and the gaps here and there through which the irresistible force of suction and the pressure of the other cells about us would tend to draw us. Should we jdeld and drift hither or thither into the pulp-cords, we should find ourselves face to face with a wonderful variety of cellular beings : here a reticular connective-tissue cell with its bulky nucleus and spindley cell-body ; there an adventitial cell with similar char- acters, save that its extremities pass off into thick pseudopodia ; there, again, a similar adventitial cell, which has drawn in its processes preparatory to detaching itself from its neighbours ; again, another which has just moved from a cave-like nook, and is about to settle down again in another spot, or is about to undergo intracellular (nuclear) metaplasia ; again, another which is waiting for its prey — dying red-cells or what not — in those dim recesses, like an octopus waiting in its lair at the bottom of the rocky crannies of the ocean floor to devour any animals suitable for food that may pass by its tentacles. The octopus seizes its prey with lightning rapidity ; but the phagocyte appears to require an appreciable time for the capture of its food. Even so, there is ample time, because we can move so very slowly through all this maze of reti- cular tissue. Passing on further amongst the cellular inhabitants we encounter here a plasmoid cell, there a macroplasma cell, here an eosinophile cell, there a mast cell, here a lymphocyte from a neighbouring Malpighian follicle, there a cell loaded with pigment. Nor do we only experience visual impressions (as it were). In the course of our imagined passage through the pulpar strands we should experience new sensations, or whatever they may be called — chemotactic influences produced by the diffusion in different concentrations of stimulant or noxious products — waste matters derived from remote parts of the body, toxic bodies from passing unimportant organismal infections of far-off regions, changes in ionic concentration of the medium, advent of different colloidal bodies. The very presence of clusters of eosinophile, plasma, or mast cells is proof of the existence of such agents, and althotigh as red-cell we should not necessarily become aware of them, this metaphorical description must take them into account. Ultimately, passing out of the view depicted in the plate, drawn along by the powerful F'S- VI- -Splen-ic Pri.p Tissi-E of Pltpv, showing Megakaryocytes are shown. The nucleus has the chuvacterisUc lobei or basket form. (Oc. 4. Three very large cells Zeiss Oil-iiiinicrsion). /•«<-,•/. /f./| The Structure of the Pulpar Tissue 161 suction of the blood-stream, we find ourselves at last in a more and more rapid current as we enter the larger and larger venous channels. The cell-constituents of the splenic pulp include the following : (i) The reticular cells themselves, which are at certain times actively phagocytic, as shown by the presence in them of pigment granules of various sizes. (2) The so-called spleen phagocytes, which are lymphoid in character, smaller than the preceding, and contain foreign bodies such as red-cells in various stages of disintegration. (3) Endothelial cells, already described. (4) The true pulpar cell and its various derivatives — the small lymphocyte, the large mono- nuclear leucocyte, plasma cells of various sizes, eosinophUe cells of various sizes. (5) Normoblasts occasionally. (6) Giant cells or megakaryocytes. (7) Purely stromatic cells. ^ (8) Kalatschnikoff^ described ciliated cells amongst the pulp-cells, which might possibly serve to direct the blood-flow into certain districts. (9) The cells of the circulating blood* The Giant Cells were first found in the spleen by Perl- meschko,3 in 1867. They are of considerable interest, since they are very close simulators of the megakaryocyte of the bone-marrow, although forms occur which contain nuclei so lobed as to appear as multiple discrete centrally-situated bodies. They appear to be constant in young animals, such as the puppy {Fig. 39), and are important in relation to certain of the metaplastic processes to be discussed later. The histology of the spleen pulp is not complete without reference on the one hand to the elastic fibrils which permeate it, and on the other to nerve fibrils. The latter end partly in the Malpighian bodies, and run in different directions to form anastomoses within them, partly envelop the brush-arteries in plexus fashion, become varicose and tortuous, and send off lateral branches to the pulp. Multipolar ganglion cells occur round the brush-arteries and vascular sheath (Asai). Metabolic Changes in the Pulpar Tissue.— Observations on the spleen during the digestion of albuminoids (Ciaccio and Pizzini^) show that enlargement takes place at this time from hyperaemia. * The remarks as to the cellular content of the splenic cords apply in every respect to the lymphatic cords, and in discussing the metabolic changes of the one, the other is also implied* II 162 Biology of the Blood-cells The nuclei of the capsular cells increase in size, and their chroniatin increases in density, while the cytoplasm becomes faintly granular. The septal veins dilate, the Malpighian bodies swell, their germ centres become distinct, and their lymphoid-cell contour becomes ill-defined. The engulfing of leucocytes causes the cytoplasm of the pulpar cells to swell greatly. The endothelium of the distended venous channels becomes tumefied, and their nuclei undergo similar changes to those referred to in the case of the capsular cells. These cells may also play the part of phagocytes, become detached, and wander away from their original positions. During this phase, the vicinity of the vessels is thronged with lymphocytes, leucocytoid lymphocytes, large mononuclear leucocytes, and erythrophages. Plasma-cells occur in clusters in a similar position, while polynuclear leucocytes make their appearance after the fashion of policemen vigilating the incoming material. The increased haemolysis which is noticed in the spleen pulp at this time, goes hand in hand with an increased red-cell manufacture in the bone-marrow (Pirones). Megakaryocytes undergo no altera- tion in the spleen, contrary to the expectation of the theory which has been advanced that they secrete a ferment necessary for digestive processes in the intestine. The active digestion of the nuclei of polynuclear cells and of some of the lymphocytes is manifested by a formation of nucleinic granules, which ultimately turn into purin substances (catabolic processes). The anabolism is shown by the appearance of nucleases, which are increased in amount pari passu with an increase of activity of lymphoid tissue and with an increase in phagocytic activity. At the same time, large mononuclear leucocytes are being made, the feebly basophUe cytoplasm becoming more and more acid, and acquiring an increasingly distinct alveolar structure as liquid ferment or pro-ferment appears within its body (the macrocytase of Metchnikoff, which acts like trypsin, amoebo- diastase, or actinodiastase). The connective-tissue cells run into a Plasmodium with large oval nuclei and two or three central chromatic dots. A ring of basophUe cytoplasm appears round the nuclear matter, and ultimately leaves the cell-complex as a lymphogonia or lymphoblastic monocyte. This becomes more and more basophile. The basophUe deposit is a constructive process. The Structure of the Pulpar Tissue 163 Dioring rest the pulp tissue is found to be poor in free elements, and degenerative nuclear changes can otten be observed. The ability to demonstrate increase in the purin content is also charac- teristic. Pathologically, metabolic changes in the spleen are exemplified from a study of the spleen in acute infections (Ciaccio'). When the follicles atrophy, the pulp shows paucity of cellular elements. Nucleinic degeneration, where the nucleoproteid or nucleohistone has become converted into a nucleic acid and proteins under the influence of a ferment, is shown by caryorrhexis and pycnosis of the pulpar cell. A more advanced stage of degeneration (purinic) may occur, in which case the nucleic acid has been split into purins, phosphoric acid, and carbohydrate. A lecithinic and fatty degenera- tion is also observed in some cases. The reticular cells may show degenerative phenomena under these conditions. The changes arising from metabolism are not completely covered by a consideration of the changes arising during the digestion of food-substances. This is well brought out by the careful cyto- chemical studies of splenic pulp by Loele.s The remarks which foUow are largely drawn from his work. This observer, applying the Winkler-Schultze oxydase reaction, ascertained that a-naphthol alone will suffice to produce the appearance of brownish-yellow pigment within the bodies of certain of the cell constituents of the splenic pulp. The substance that renders this reaction possible is called the " phenolphilic substance," and the phenomenon itself is called " phenolphilia." It was observed that phenolphilic substance was diminished in some cases of chronic nephritis and chronic syphilis, but increased in infective processes and in cases of breaking-down neoplasm. Expressed more fully, we find that the following groups may be constructed : (i) Cases in which there is general deficiency of phenolphilic cells through the splenic tissue ; (2) Cases in which a narrow zone of granular cells occurs round the follicles, but only isolated cells are to be found in the pulp ; (3) Where the perifolli- cular zone of cells is broad, and phenolphilic cells are fairly numerous ui the remainder of the pulp ; (4) Cases in which the cells are abundant throughout. The second type may be regarded as the 164 Biology of the Blood-cells normal one during the stage of digestion in the adult. The first group is met with in chronic renal diseases, as mentioned above, and the third group is noted in the acute infections. The fourth group is characteristic of septic conditions (abscess of the liver, pylephlebitis, meningitis, peritonitis), cirrhosis of the liver, diabetes, and unclassifiable conditions. Loele arrived at the following conclusions about the chemical nature of the phenolphilic substance : (i) The phenolphilic sub- stance is an amido-aldehyde base endowed with properties resembling those of ferments. It may act as a reductase, or as an oxydase (phenolase) according to the concomitant circumstances. As a base, it is demonstrable by means of the a-naphthol reaction alone ; (2) As base it may manifest itself in the form of granules, and form soluble salts with acids, or unite with phenols in alkaline solution to form colour salts (after the fashion of hydroxylamine). As an ammonium base it serves to saponify fats, and is able to dissolve albumin when combined with certain intracellular acids (lipolytic and proteolytic ferments) ; (3) Nitrogen bases are increased in response to electro-chemically negative stimuli (acids, phenols, alcohols), — N = N— becomes — N =, — N =. It has already been pointed out that the Malpighian follicles are built up round the arteries, while the pulp is essentially venous. The significance of this well-known anatomical point is well demon- strated by the author just named. Granted that there is pheno- philic substance in the follicle cells, the effect of its presence is to take up the oxygen circulating past them, and liberate it once more in nascent form, so that coming in contact with aldehyde groups as it does, the latter become oxidized into amido-acids. Cells rich in amino- acids obviously appear " basophile " in the stained histo- logical preparation ; hence the " foci of basophilia " commonly called Malpighian bodies. Siegfrieda pointed out that the carbon dioxide produced by metabolism would unite with the amido-acids to form carbaminic acid, which, in the presence of the sodium chloride of the blood, would give rise to hydrochloric acid and sodium carbonate. The latter is removed by the lymphatics around the follicles, while the former unites with amido-bases within the cells (e.g. of the lymphoblasts), breaks up the peptonizable The Structure of the Pulpar Tissue 165 proteins — a phenomenon of autolysis — and brings about the appear- ance of cells with hardly anything but nucleus, the familiar lympho- cytar cells. Meanwhile, the continued supply of oxygen has led to the appearance of pseudocrystalline matter within the cells, other- wise called mitotic figures, and an actual division of the cells into two.* The pulpar tissuej on the other hand, is bathed in a medium relatively rich in carbon dioxide, except in the vicinity of the follicles, where the reaction of the tissue is neutral. The absence of lymphatics serves the definite purpose, or has the definite effect, of maintaining this semi-asphyxial state, for there is no opportunity of draining off the carbon compoimd in the form of carbonate. The surfeit of this substance leads to the accumulation of auto-oxidizable nitrogen bases— of phenolphilic substance within the cells, because the bases are attracted into the cell-body by the excess of amido- acids in the nucle-uberous cells. The further removed the cells are from the arterial zone, and the less opportunity is there for the production of basophile, differentiated cell structures, the more should one find uniformity of morphology between them. Where ceUs such as eosinophiles appear, which bear oxidizing granules, there wUl be some disturbance of equilibrium, and this is rectified, for instance, by the appearance of plasma-cells. Wherever noxae of acid character reach the cells via a venous medium, phenolphilic granules will appear within them, whereas, as shown, they have no opportimity to accumulate in the immediate vicinity of the arterial channels. The basophile substances in the pulpar tissue tend to the formation of tryptic systems therein (in place of the peptic system characteristic of the follicles), and the effect is that oxyphilic bodies are liberated in the pulp while the autolytic macrophages are correspondingly numerous. From these condensed remarks it is evident that the splenic pulp contains bodies which are able to make colour salts with phenols, and can neutralize acids brought to it, as well, as bind decomposed phenol-like compounds to the alkaline tissue juices, and perhaps saponify neutral fats. The phenolphilic granule, in a * Leduc's physico-chemical theory of mitosis will be recalled. 166 Biology of the Blood-cells sense, acts as an amboceptor between the phenolic compound and the alkaline tissue juice, while in the process of saponification the granules play the part of complement, and cause the neutral fat to hydrolyse into a soap. Expressed in this way, the importance which the writer attaches to Loele's theories is more clearly brought out. We see that the presence of this material in such abundance in the spleen invests this organ with a new significance, in preventing the liberation into the blood of an excess of amino-bodies. When- ever metabolic processes result in the liberation of excess of acid substances by the tissues, the diminished alkalinity of the blood is rendered innocuous to the body as a whole by the phenolphUic sub- stance formed in the spleen (also lymph-nodes and round eosino- philic zones). The chemical structure of the phenolphilic substance has been surmised from a number of considerations. It is regarded by Loele as derived partly from the nucleus and partly from the cell-body. One would express the views under consideration by the following scheme : — NUCLEUS < COH 1 ACID — >■ CELL-BODY COH 1 1 >N II -N 1 >H 11 -N becomes COH 1 >N = (COOH) (phenolphilic substance) + - N = (COOH) The acids diffuse into the cell-body and unite to the N group. (COOH) becomes free ; and the O attacks the COH, or unites with phenols, or becomes free. The aldehyde group becomes acid (COOH), to wit an amido-acid within the nucleus. Should phenols not be present within the nucleus, the heaping up of amido-acids leads to the phenomena of mitosis. In the histological process, a phenol-ring is supplied to the cells, and with the phenolphihc sub- stance gives rise to a colour salt of oxazin type. The Structure of the Pulpar Tissue 167 The phenolphilic substance is increased by the presence of bacterial toxins, by salvarsan, and by the toxic agencies responsible for the diseases called pseudo-leukaemia. It is diminished by the presence of acidosis. The Functions of the Spleen. — 1. Phagocytosis by macro- (not micro-) phages. R. Blumenthal" stated that the spleen was the battle-field between the organism and its invaders. Another author has described the organ as the graveyard of the red cell. 2. Erythrolysis — shown by the abundance of extractives in the organ. 3. Leucolysis (Blumenthal). Spleen juice destroys leucocytes. 4. Removal from the blood of abnormal products other than cells. 5. Hormonistic functions,* such as supplying an activator to the pancreatic trypsin (trypsinogenic function of Herzen,'^ corroborated by Pachon and Gachet, but not accepted by Pawlow) ; or supplying an activator to pepsin, t 6. Erythropoiesis during embryonic life.J 7. Monocytopoiesis in the adult, but monocytoid cells increase in the blood after splenectomy (Pauliczek,!' Creszenzi, Azzurini). 8. Utilization of iron (Asher.i* Grossenbacher, and Zimmermann^') ; this is shown by the fact that after splenectomy the urine contains increase of iron, whUe if an iron-free diet be given at the same time, there is a very rapid development of anaeifiia. In leukaemia and Banti's disease there is iron-retention. 9. The functions connected with the Ijnnphocytes (i.e., of the germ- centres). These are similar to those met with in the case of the lymph-node ; e.g., relation to lipolysis and immunization against organisms which contain lipoid material. 10. Relations to immunity. These are not clear. SzokalsW considered that there was no relation to the formation of haemolysins, because splenectomy does not destroy haamolysin formation. Jungano^' and Azzurini^* considered that agglutinins are not made here, but Scotti^' found very definite evidence of their manufacture in this viscus. Bergel.^" on the other hand, found evidence that antibodies for haemolysins were made in the pulp, because extract of spleen in a case of cancer would relieve cancer in any animal (acts as an immune serum — Braunstein)."! Oser and Pribram^^" found that splenectomy in rats the subject of sarcoma would cause the tumour to increase rapidly in size; while an injection of spleen-pulp would cause the growth to cease. 11. Myeloid transformation. This is considered in Chapter VII. • This term appears to be unsatisfactory, from the evidence afforded by the researches of Popielski^'' and others (in Russia, particularly). In other words, hormones may not be entities at all, but " chemical affinities," or, possibly, in the writer's view, stereochemical attributes, much as may hold good in the case of some amboceptors. t Gross" found that the pepsin was extremely low in a case of splenectomy for trauma, while lymphocytosis appeared. t The proof that enterokinase is made by the spleen lies in finding increase of the kinase after injecting nucleinic acid or pilocarpine into a dog. The source of the kinase is not the lymphocyte, because that is always present. It Is not the polynuclear leucocyte, because bone-marrow itself has no such power ; the macrophage must therefore be the source. 168 Biology of the Blood-cells It is evident, then, that the spleen subserves a number of functions, which do not deserve contempt on the ground that splenectomy is harmless, but rather are to be regarded as so important and necessary to the organism that they are not condensed into one organ alone, hut are part of the potentialities of widely disseminated mesenchymal cellular elements. The result of this plan of dividing risks in speculation among a number of investments is manifested by the successful (i.e., non-fatal) splenectomy referred to. Dinkier" recorded a case where splenectomy was followed by polycy- thaemia. The Accessory Pulp-cell Factories.— A. Accessory Spleen (Accessory splenoma — Faltinss). This body may be met with singly or in multiple. Winkler 2 * and Albrecht have each reported cases in which there were hundreds present. It is usually discussed as a purely anatomical curiosity, and the situa- tions in which it is apt to appear are stated with detail. The following brief remarks may be more suggestive — ^namely, that the accessory spleen is well-named : that it is truly accessory in charac- ter ; that it plays a required part ; and that it can develop at any time, and in any place, from indifferent mesenchyme cells.* It will be evident that there is no reason why an accessory spleen should not develop at any time, if the parallel in lymphoid tissues holds good. The Ribbert lymphoma may arise into promi- nence at any time when occasion demands, and lymph-nodes appear in just the same way amongst the fatty tissue of the mesentery and axilla. We have, moreover, the records that accessory spleens have been noticed to be frequent after extirpation of the spleen (Ljtten, Tizzoni,2 7 and Hosier), e.g. for rupture (Faltin^s). The structure of these organs is very similar to that of the main viscus. The writer has found them to be rather poorly provided with follicular tissue. B. The H^molymph-gland. — The hasmolymph-gland is a constant anatomical feature of both man and mammals. It is particularly common in the horse (Fourgeot^o) ; is frequent, but less conspicuous, in the sheep and rat ; but not easily seen in the dog and cat. * It will be remembered that the spleen itself develops from the mesenchyme of the dorsal mesentery in close connection with the mesenteric arteries. It appears as a thickening of the lymphoid tissue which surrounds the wall of the artery at an early stage (Radford'"). The Structure of the Pulpar Tissue 169 Such glands also occur as the " head kidney" of fishes (Lewis"), in birds (Vincent and Harrison'') , and in swine suffering from Texas fever (Warthin'^) . It will be noted that birds possess but few lymph-nodes of the ordinary type (Quain32). Briefly described, it is a lymph-node of deep-red colour owing to communications between blood, vascular channels, and lymph sinuses. In a sense, the hsemolymph-gland is nothing more than an accessory spleen. The lymphatic channels are reduced to a minimum, and do not form so definite a system as in the ordinary l5Tnph-node, while the lymphoid cells are very irregularly arranged, and exhibit no definite follicular arrangement. In the ruminants, there are afferent and efferent lymphatics, besides a closed system of lymphatic channels. The lymph in the former is of a red colour. It is usually stated that these bodies are normally present on each side of the aorta, but the percentage of autopsies in which this can be corroborated is rather small, and really confined to instances of microbic infection.* Other situations for these glands are : the bifurcation of the trachea, the chain of glands leading from the appendix, and the gland above the head of the pancreas. The following types of haemolymph-glands are often described : 1. The splenic type, met with in the retroperitoneal and thoracic regions. This is a small lymph-node with blood-sinuses and no Malpighian bodies. The sinuses are large, and have macrophages for red-ceUs and for pigment within them. This type is really an example of " splenoid metaplasia " {p. 308). 2. The myeloid type. This is only seen in the retroperitoneal region of animals. The tissue resembles red marrow in structure. Warthin termed such glands " marrow lymph-glands." The blood sinuses are smaller, and contain many basophile and sometimes giant cells. This form is also classifiable as a variant of myeloid metaplasia, a conception which brings together lymph-nodes show- ing myeloid metaplasia and the form of hsemolymph-gland in question. 3. Intermediate Forms. — Intermediate stages between (i) and (2) may occur as well as between hsemolymph-glands and glands in * They have also been found in cases of corrosive-sublimate poisoning. 170 Biology of the Blood-cells general. If the sinuses contain some lymph they are called h^mal lymph-glands (Robertson), while if they contain only blood they are called haemal glands. In some hsemorrhagic diseases, haemolymph-glands are simu- lated by specimens through which diffuse haemorrhage has taken place, and sometimes by specimens showing petechial haemorrhages scattered through their substance. As has been stated, the spleen is really a large haemolymph- gland. The junctions which have been assigned to haemolymph-glands are : (i) Making lymphocytes ; (2) Making eosinophile cells by taking up disinte- gration products of red cells (the nuclei become polymorphous — Woltmann*^) ; (3) Destruction of red cells (bilirubin formation) ; (4) Destruction of white cells by phagocytosis. The Large Mononuclear Leucocyte 171 II.— ON THE LARGE MONONUCLEAR LEUCOCYTE OF THE BLOOD-STREAM. The meaning of the terms : large mononuclear leucocyte, splenocyte, monocyte, lympholeucocyte — Pappenheim's monocyte : its morphology : contrast between the two varieties of monocyte — The morphological characters of the large mononuclear leucocyte : the secretory vacuoles — The variants : the lymphocytoid, transitionsi, miniature, and giant forms — The differential diagnosis — The theories as to the origin of the large mononuclear leucocyte of the blood-stream (myeloid, lymphoid, endothelial) — The birth of the cell into the blood-stream — The functions of the large mononuclear : Numerical variations — Chemical characters : the azur granules — Comparative cytology — The fate of the large mononuclear leucocyte — Transitional cell : degenerative changes : irritation changes : reversion to tissue-spaces. The classification and enumeration of the white cells in a blood- film would be quite straightforward were the polynuclears, . the eosinophiles, the mast ceUs, and the small lymphocytes the only variants to be considered. The existence of other lymphoid cells has been the cause of much controversy, partly because their morphology has not been clearly defined, and partly because of an absence of definite information about their source. These larger lymphoid cells were called large mononuclear leucocytes by Ehrlich, who considered that, after passing through a " transitional-cell " phase, they became neutrophile leucocytes. Metchnikoff, desig- nating them as " macrophages " because of their power of taking up large particles of foreign matter, regarded them as identical with the wandering cells of Marchand. This view agrees to some extent with that of NaegeU, in that the latter emphasized their specific function as indicative of their belonging to a distinct order. Patella's view that they are dead cells may be put on one side, because it fails to recognize the profound biological importance of the group. Some years ago it was thought that this cell-form was derived from the spleen, and might be correctly designated by the word splenocyte (Tiirk), but there are certain considerations which show that the spleen cannot be the only source of the large mononuclear leucocyte. Although the spleen pulp consists largely of such 172 Biology of the Blood-cells cells, although the splenic vein is rich in them, yet splenectomy is followed after a time by a marked increase in the large mono- nuclears.36 It is more probable that we should speak of these cells as being derived from the pulpar tissues, whether of lymph-node or spleen, not only because this procedure is more in keeping with the physiological attributes of these hsemopoietic organs, but also because the possibility, after splenectomy, of continued supply of the cells under consideration would find a natural explanation. In consequence, it would be better to speak of " pulpocytes " rather than " splenocytes," though the introduction of new terms is neither necessary nor desirable. Having once fixed what kind of a cell is a large mononuclear leucocyte, or a monocyte, further alterations of nomenclature become avoidable, even though findings from the etiological side should come to light. It was with the object of simplifying the subject that Pappen- heim introduced the term monocyte to group together those cells usually classified by laboratory workers as " monos " (an abbrevia- tion of wjoMonuclear leucocyte). Such cell-forms may be separated off into {a) the so-called normal monocyte, (6) the leucoblastic or granuloplastic monocyte, each of which exhibits the characteristic leucocytoid form when it becomes old. According to this method, some monocytes become definitely lymphoid in character — lipase- containing ; while the others are ancestors of granular cells — oxydase and proteolase-containing. But both forms are possible functional phases of one and the same cell-form (monocyte, or its parental form, the lymphoidocyte). If the monocyte has lympho- cytar characters, it persists with such ; if it has granuloplastic characters, it passes on further to become a polynuclear leucocyte. This conception tends to simplify the difficulties which the investigation of blood-films presents. Everyone has noticed how similar the basophile mononuclear cells with indented or horse- shoe-shaped nucleus are to certain pathological cell-forms called myelocytes. The distinction between them is apt to be very fine, and appears forced to the uninitiated. On the other hand, it is important to search for data which will help to detect functional differences in morphologically similar cells. The first step towards this is gained by the use of the term in question. If there is The Large Mononuclear Leucocyte 173 evidence that the monocyte is leucoblastic or myeloic (forming or about to form neutrophile granules), then the blood in which it was found is abnormal and the cause of the abnormality requires to be determined. The type of monocyte natural to the blood- stream, on the other hand, is lymphoblastic if anything, and must be placed in a class apart from the other.* The monocyte of Pappenheim is related to the mesenchymal cell of the tissues, the clasmatocyte of Ranvier, the endothelial cell, and the lymphoid wandering cell of Marchand. Present in every tissue of the body as cells with a vesicular leptochromatic nucleus, they give rise to a form with a darkly-staining nucleus which may remain latent or slumbering as the pulpar monocyte, may simply proliferate and appear as a lymphatic monocyte, or may develop along metaplastic lines to form granulocytes. The natural situation for the latter change is in the bone-marrow, but under certain circumstances it occurs in the pulpar tissues, and is then named myeloid metaplasia, f The monocyte of the blood is a morphological entity, and it is not possible to decide whether a given cell seen in a film has come from the pulp, the follicle, the marrow, the perithelium, or elsewhere. It is certain that it cannot be derived from the lymphoid follicles directly, because we should then have to accept the existence of immature or ancestral cells in the circulating blood. Similarly, the discussion as to whether a transitional ceU ends its life as a neutrophile leucocyte is superfluous, because if it were so it could not be a transitional cell but a metamyelocyte. The characters of the metamyelocyte are easily defined, and there is no need to confuse the two. Similarly, if the young transitional cell inevitably became a neutrophUe, it should be called a promyelocyte (see next chapter). On the other hand, the discovery of azur granules in both series of cells has led to much confusion, although later researches have shown that the azur granules of the lymphoid cells are differentiable and distinct from those of the myeloid series. * The synonyms, splenomonocyte, macrolymphocytar endothelioid cell, etc., are gathered together in the Glossary. f As will be shown later, this view of myeloid metaplasia is not universally accepted. 174 Biology of the Blood-cells The Morphology of the Monocyte.— Size. — Large, up to 25 /i. Shape. — Rounded or ovoid. Contour. — Fairly clearly defined. Cell-body. — Is very feebly basophile ; is transparent ; may show a very fine spongioplasmic network. The leucoblastic monocyte has a distinctly basophile cell-body.* Granules. — Very fine, numerous azur granules occur. Nucleus. — Is rather Hi-defined. Outline irregular. Size large, both absolutely and relatively. Staining power feeble. Nucleolus. — ^Never present. The term lympholeucocyte (Pappenheim, Coies^) means no more than a cell combining certain features characteristic of the leucocyte (relatively large cell-body, irregular contour of nucleus) with other characteristics of lymphocytes (especi- ally the diffuse basophilia). It is really a senile form of the large mononuclear leucocyte, although forms occur which are not easUy distinguished from the senile or leucocytoid forms of the small lymphocyte (so-called " hyaline cells " of older writers). The alteration of terminology to indicate alterations of age in these orders of cells is best shown by the following : — Large lymphocyte = lympholeucocyte = transitional cell. Small lymphocyte =leucoc3rtoid lymphocyte =lymphocjrte with reniform nucleus. This scheme accentuates the position of the transitional cell as the terminal of the lymphatic monocyte line, and should be compared with that of the polynuclear cell as the terminal of the myeloic monocyte line. In each case the law of ageing holds good; that is, the nucleus shrinks, loses its parachromatin, becomes indented or pycnotic, and relatively smaller to the cell-body. * The fact that the colour of the celljbody of the leucoblastic cell (panoptic stain) is better imitated by cobalt blue indicates the amphochromophilic change that is taking place in such cells. The Large Mononuclear Leucocyte 175 Contrasting the two categories of monocyte, we have Lymphatic Monocyte Leucoblastic Monocyte Bulky Smaller Contour rather irregular Regular Ovoid Round or irregular Contour rather ill-defined More defined With panoptic, cell-body stains Stains cobalt blue or violet blue, or Prussian blue grey violet Azur granules fine Coarse, fewer Nuclear markings ill-defined Clear ; more or less transverse polygonal shadows Size of nucleus relatively small Relatively larger, especially in young cells Nuclear membrane definite Not definite These points are shown in Fig. 40. Cb o Fig. 40. — ^The Two Forms of Monocyte, (a), I*eucoblast with coarse azur granules and coarse nuclear membrane ; (6), large mononuclear leucocyte with fine azur granules, and d^cate nuclear mem- brane; (c), promyelocyte with neutrophile granules and partially oxyphilic cytoplasm, indicated by purple stippling. This cell is introduced to form a contrast to a and h. The following table will emphasize the difference in the character of the granules of various monocytes : — Lymphoid Cells with Basophile Cytoplasm. Group A Group B Group C Group D Stained with TriAcid Stained with Romanowsky Shows no granules Shows no granules Shows some granules Shows some granules Shows no granules Shows some granules Shows no granules Shows some granules Cells belonging to group A are primordial or mother cells, to group B are monocytes (in a general sense). The remaining groups are forms of promyelocyte. 176 Biology of the Blood-cells The morphological differences between the lymphatic monocyte and the leucocytoid lymphocyte are shown in Fig. 38, wherein are to be noticed such points as centric or excentric position of the nucleus, vacuolation of cytoplasm or hyaline cell substance, size and position of azur granules. Fig. 41. — Row a, large mononuclear leucocytes; row 6, leucocytoid lymphocytes. Diagrammatic drawing to emphasize the points of distinction between the two series. The heavy outline of the nucleus in b indicates the dearer definition of the nudear membrane, and the shadowing indicates the more intense staining power of the nuclear matter. The Morphological Characters of the Large Mononuclear Leucocyte.— (See Figs. 40, 41). Size. — Up to 20 or 25 f* in diameter. Shape. — Ovoid. Contour. — Faint but regular. Internal Structure of Cell-body. — ^The cytoplasm is relatively abundant, is feebly but purely basophile in reaction, is transparent, or shows a very fine spongioplastic network. Vacuoles are very rarely observable. At the periphery of the cell-body are some very minute rod-like basophile structures, but the edge is not very basophile. Astrosfhere. — There is a very feebly ox3^hile perinuclear halo in some specimens. Granules. — The following varieties are described : (i) Very fine (feebly orange) azur granules, scattered uniformly through the cell-body in considerable numbers. They may be situated more at the periphery than at the centre ; (2) Ferrata's plasmosomes ; (3) Kurloff bodies. These two last-named are referred to briefly under the title of secretory vacuoles ; (4) Winkler-Schultze granules were observed by Sapegus.^s The Large Mononuclear Leucocyte l77 Nucleus. — This is large, both absolutely and relatively (7-10 n). It is round or oval in shape, is usually indented or lobate to a varying degree. The position is slightly excentric. The staining power is feeble (amblychromatic), and shows an almost absolute homogeneity owing to the lack of differentiation of chromatin from parachromatin. The lining has the appearance of shadowing (woolly or flaky). The nuclear membrane is feebly defined. Nucleolus. — Never present. Mitoses. — Amitosis is only observable in atypical forms (Spadaro39). Appearances with Ultra-violet Light. — Grawitz^o found that various examples occur which will show all stages between flaky differentiation of cytoplasm and granule formation. Isomorphous Cell. — Leucocytoid leucoblast. The Secretory Vacuoles. — Secretory vacuoles occur in 15 to 20 per cent of the large mononuclear cells of the normal guinea-pig. They were first described by Kurloff.*i These bodies vary considerably in size, are single, paranuclear, and are not readily stained by any dyes except the vital stains and the Romanowsky methods. They stain metachromatically with azur. They may include definite azur granules. Similar structures have been described and figured by Pappenheira*^ in the large lymphocytes or primordial cells of leukaemia. Views as to nature : — 1. They are parasitic (Patella*'). Pro : It has been claimed that flagellate structures have been seen in them by vital staining. The Kurloff body itself has been looked on as a nucleus, the perinuclear halo being the cytoplasm. They are more numerous in animals kept under unhygienic conditions. They are absent from guinea-pigs fed on sterile food.* Con. : (a) They do not disappear with quinine or atoxyl treatment (Pappenheim**) ; (6) Living parasites are not vital-stainable ; (c) Living parasites stain metachromatically with basic dyes ; (d) The only azurophile structure in a parasite is the chromatin body ; (e) Inoculation from one guinea-pig to another does not transmit the " disease."*^ 2. They are secretory.** (a) They are vital-stainable ; (6) Basic dyes do not stain them ; (c) The whole Kurlofi body is azurophile ; {d) The staining is absolutely homogeneous (except when acid fixation has been employed, when an appearance hke the retracted colloid in thyroid acini is produced) ; (e) Ciaccio*' has shown that they come from the nucleoli. 3. That they are giant azur granules formed by fusion of small ones. All transitions have been observed. * McDonagh regards the "vacuoles" as phases in the life history of a trypanosome. Similar inclusions found in chancres are believed by him to represent phases in the life cycle of the organism of syphilis. (Proc. Roy. Soc. Med. 1912, Dec. 3, p. 85 of Pathological Section). 12 178 Biology of the Blood-cells Variants. — 1. The Lymphocytoid Form. — This is met with chiefly in the blood of children, and maybe looked on as a juvenile form of mono- cyte. Its morphology differs from the main t5^e chiefly in the fact that the cell-body is relatively scanty, and the nucleus pre- dominant and rounded. A distinction of less striking character is the greater basophilia of the nucleus, though there is no better differentiation of chromatin than in the type form. The question has arisen whether this is the same as the lymphoblast of the germ centre. However, they are presumably not identical, because the presence of such a cell in the blood would be pathological ipso facto, while the lymphocytoid large mononuclear has been met with by the writer in blood-films from apparently healthy individuals. 2. The Transitional Cell. — This cell appears in the blood- stream form the fifth to the sixth month of fcetal life (Griineberg^s). It presents many features in common with the type cell, but its essential feature is the deeply indented nucleus, which has now attained a horse-shoe form in weU-raarked specimens. The para- plasm remains feebly basophile, no trace of oxyphilia being ever noticeable (distinction from metamyelocyte). The more indent the nucleus, the more intensely does the cell stain with basic dyes. Azur granules are only occasionally seen. Opacity to ultra-violet light is variable {Grawitz*^). Isomorphous Cell. — Leucocytoid Rieder-like leucoblast. This cell-form is regarded as a senile large mononuclear leucocyte. 3. Miniature Forms occur which have the aspect of lympho- cytes, but possess an irregular large vesicular nucleus. Azurophile granulation is present. 4. Giant Forms, either rich in, or devoid of, azur granules, are described by Ferrata and Pappenheim.so The Differential Diagnosis of the Large Mononuclear Leucocyte. — This has been partly discussed in tabular form on preceding pages. It is convenient to list the similar cells at this stage : — The Large Mononuclear Leucocyte 179 1. The leucocytoid lymphocyte (see Fig. 41). 2. The leucoblast (see Fig. 40). 3. The leucoblast without azur granules is similar in all other respects to No. 2. 4. The myelolymphocyte, or myeloic pseudo-lymphoc5rte, is really a daughter-lymphoidocyte and possesses the distinctive characters of the parent or primordial cell. 5. The lymphoblastic macro-lymphoc3rte (see Table, on p. 32). 6. The leucocjrtoid form of the preceding is a mere variant, in the existence of a relative abundance of cytoplasm. 7. Irritation forms. Here the chief points are the deep basophilia of the cell-body, the distinct perinuclear halo, and the tendency to radial arrangement of the main chromatin trabeculae. 8. Promyelocyte. The oxyphilic cell-body and the neutrophile granules are distinctive. 9. Rieder forms. Here the nucleus has marked affinity for basic dyes. 10. Degenerated cells may simulate. Desquamated endothelial cells are 24-52 fi in diameter, have angular edges, and rarely show chromatin structure. The cell-body is very transparent and shows a broad-meshed reticulum. The nucleus is small, oval, and often excentric, having a feeble chromatin reticulum. Vacuoles are present, and metachromatic material may be present (Spadaro^^). Paremusofi^^ considered the large mononuclears of malarial blood to be degenerated lymphocytes functioning as pigmentophages. The Theories- as to the Origin of the Large Mononuclear Leucocyte of the Blood-stream. — The various views which have been advanced on this subject are most conveniently expressed in schematic form, using the following abbreviations : — Poly = polynuclear leucocyte ; 1 = lymphocyte ; Tr = tran- sitional cell ; L L = large lymphocyte ; L-L = lymphoidocyte ; L M = large mononuclear leucocyte ; L M C = lymphoid marrow ceU or myeloblast : My = myelocyte ; Spl = large lymphoid cell of spleen. a. (i) LM ^ Tr -> Poly (ii) 1 b. 1 -> Meso-1 ^ LM ^ Tr -♦ Poly Tr ^ Poly c. d. 1 ^ LM ^ My 1 -V L-L -> LM 1 My- (i) L M C -> L M My Spl -> LM Marchand CeU -> e. f- S- (ii) 1 -»• L L -> leucocytoid L L LM 180 Biology of the Blood-cells (a) is Ehrlich's original view, (b) is Grawitz's, (c) is Weiden- reich's, (d) is the unitarian view, (e) is Ziegler's and Schridde's, (/) is Helly's, and (g) has been advocated by Pappenheim. The latter writer has tabulated the genetic relations somewhat after the following manner, the cells named on each line being iso- morphous : — >• l3nnphoidocyte I ^ leucoblast ft. macrol5miphocyte >• ^ I monocyte 4, + '• -I- micromonocyte-microljmiphocyte-microlymphoidocyte-microleucoblast ; and /. L L -^ macro-1 -> L M ^ Tr In favour of the last-named views are the arguments used against (b-d) and (e). Views (b-d), that the cell is of lymphoid origin (Jolly, Wolff, BlumenthaJ, Maximow, Weidenreich, and others). In favour of this is the fact that all the cells of the series have a basophile cyto- plasm, azur granules, and nucleoli. Against it are the differences between the large mononuclear and the lymphocyte : — Large Mononuclear Small Lymphocyte Form irregular . . Regular Cytoplasm very basophile Feebly basophile and shows foamy structure Azur granules very fine . . Coarser, spherical, unequal abundant Scanty closely packed Widely separated Nucleus of irregular shape Even contour ,, stains feebly Deeply ,, stains uniformly More at periphery than centre View (e), that the cell is myeloid. This hangs or falls on the question whether the azur granules are or are not entities, or precursors of neutrophilic granules. The arguments against the theory are : — I. Every cell in the bone-marrow need not develop neutrophile granules. The Large Mononuclear Leucocyte 181 2. Increase of large mononuclear cells in the blood bears no constant relation to neutrophilia, while decrease in the total white- cell count, or neutropenia, is not associated with increase or decrease of the monocytes. 3. There is no suggestion of any lympholeucocytes becoming eosinophilic, whereas this would be anticipated from analogy with the myelocytes. 4. Those monocytes found in myeloid tissue which are accepted as precursors of neutrophiles are called promyelocytes. Another view-point is provided by Jagic.e^ who thought that some myelocytes fail to mature, and gradually lose their granules. Finally entering the blood-stream, they appear as large mono- nuclears. {k). — That it is derived from the endothelium of the blood- vessels or lymphatics (Patellas*). The arguments in favour of this view are : — 1. There is an increase of these cells in the course of infections and intoxications (such as typhoid fever, chronic anaemias). In such diseases there is endarteritis and desquamation of endothelium. The amount of mononucleosis is proportional to the degree of intoxication. In such cases, tags of endothelial cells may occur in pathological blood. 2. Massage of the limbs is followed by mononucleosis. 3. It is present in chorea. 4. Rats are regarded by Patella as very active animals, and he considers that that is why their blood is so rich in large mono- nuclear ceUs.55 5. The morphological features of the cell. It is sometimes polygonal in contour, and shows relics of the cement substance when stained with silver nitrate. It is frequently deformed. The edges are frequently wrinkled.56 There is a lamellar structure as if the cell had shrivelled since its detachment from its neighbours. The Kurloff bodies so frequent in these cells in the guinea-pig are evidences that degeneration has commenced. The nucleus possesses the same characters as that of normal arterial endothelium (senile form). Amitotic changes are always noticed whenever mono- nucleosis is marked, indicating proliferation as well as desquamation 182 Biology of the Blood-cells of the endothelium. The autolytic changes which are undergone by the blood-cell are similar to those undergone by the epithelial cell.67 6. Their undisputed occurrence in pleural and peritoneal effusions. The arguments against the view are as follows (Ferratass) : — 1. A dead cell could not be a phagocyte. 2. It is not likely that one out of every ten white cells is a " cadaver " (Carpisa). 3. The proportion of these cells in the blood is constant. This would be quite unlikely if they were desquamating cells. 4. Large mononuclear leucocytes are not increased in old persons, and may occur in cases where there can be no disease of the vessel walls (Frumkin^o). 5. Specific increase of the large mononuclears (monocytosis) due to chemotaxis cannot be due to alterations in the vessel walls. 6. True endothelial cells have quite distinctive characters (Marchiafava). 7. The irregularity of the shape of the cell and the laminated appearance are errors of technique.* 8. The Kurloff bodies in these cells are developmental changes of an azurophile secretion, and indicate progressive evolu- tion. The nucleus is retracting, as in all ageing cells. 9. It is not accepted by reputed hsematologists (Ferrata).* The following questions may be asked : What does become of shed endothelium ? Such cells must break down, die, and be desquamated at some time. Why should every large mononuclear leucocyte be a genuine blood-cell ? Could one really distinguish desquamated endothelium from a lympholeucocyte ? If serosal endothelial cells are so common in pleural and peritoneal exudates, why should not one or two vascular endothelial cells occasionally occur in the circulating blood also ? Answers to these questions may show that the endothelioid cells of Patella do actually occur in the blood-film, although they are not to be confused with the true monocyte. * Questionable arguments. " The immense phagoc\l!C celU with inclusions of inert matter are well seen " (p. 1S3). Fj,;'. 42.— Phagocttosis in Lv:mph-channel of a Ia'mph-node. la), endothelial cells containing black flakes and granules (carljun) ; (/»), vascular channels separating the cell-groups. (Oc. 2, Zeiss Oil-immersion). Faw /.. /S^] The Large Mononuclear Leucocyte 183 The Birth of the Cells into the Blood-stream.— There is little to be said under this heading. Granted that the majority of these cells come from the pulpar tissues, there are no laws apparent determining how many or which individuals shall be swept from their nesting-places at any given time. It must, how- ever, be assumed that their natural habitat is in the capillary recesses, where the stream is slow. The Functions of the Large Mononuclear Cell. — The lymphatic monocyte is best regarded as a unicellular organism endowed with motility, tactile sensibility towards cells and protozoa, and secretory and digestive functions (macrocytase). The rate of movement is sluggish, and the pseudopodia are short and slender — properties which allow them to make their way through the capillary wall into the surrounding tissue spaces. The power of phagocytosis was classically demonstratedei by injecting goose red-cells into the peritoneal cavity of a guinea-pig, after which the leucocytes were found to be apposed to them, subsequently taking them up and dissolving them, the nucleus being the last part of the red cell to disappear. The surface of contact between the leucocyte and the foreign particle is made as large as possible by means of the pseudopodia. The phenomenon is best seen in the tissue spaces, and specially well in the lymphatic channels of the lymph-nodes and spleen. The immense phagocytic cells with inclusions of inert matter are well seen in the anthra- cotic gland (the cells are here called pigment ophages).* Thus in the accompanying figure {Fig. 42) is shown a portion of such a channel as seen with the high power. Further, similar cells can be demonstrated to take up the Koch bacillus, the leprosy bacillus, and the spirillum of Obermeier. They destroy the muscular fibres in muscular atrophy and the dead nerve-cells in cerebral softening. They absorb pigment in malaria. The digestive ferment possessed by these cells is called macrocytase, which only passes into the blood itself after the cell has been destroyed. It is questionable whether the macrophage is related to Ehrlich's complement or to * The same cells in the mesenteric nodes fix the fat absorbed from the intestine. 184 Biology of the Blood-cells Ms amboceptor, but it is of interest to note that mononucleosis is a striking feature of all those infections which leave permanent immunity behind them — scarlet fever, enteric ; also in measles (Bergel62). The question of phagocytosis does not require further dis- cussion owing to the well-known character of the phenomenon. The existence of other functions might be indicated from a consideration of the causes of numerical variations in the blood. It proves, however, that though many diseases exist in which mono- cytosis or monopenia occurs, very little relation can be detected between them. The normal content is represented by the following figures : up to 5 per cent of the total white-cell count according to Rieux,6 3 5-10 per cent according to other observers. This gives 240-400 per cubic millimetre. In the newly-born they number over 15 per cent. They appear in the blood from the fifth month of foetal life (Griinsky^s). Causes of increase {monocytosis) : — 1. Fasting (Penny^*). 2. Acute infections (gangrenous appendicitis, pneumonia, at the end of typhoid fever, small-pox, scarlet feVer, after the tenth day of rubeola, acute lymphaemia).* 3. Chronic diseases : malaria, hepatic (dysenteric) abscess ; tuberculosis ; epithelioma ; symptomatic anaemia, rickets, v. Jaksch's ansemia; cardio-vascular disease (Schifone^s) ; leprosy with nerve lesions. 4. As an effect of certain drugs : pilocarpine, tuberculin, iodine (Lortol-Jacob), arsenic (Besredka), quinine (Bill). Causes of decrease {monopenia) : — This is most noticeable in progressive pernicious ansemia (absolute loss in the terminal stages) ; chronic splenomegalies (including Banti's disease). Leukaemias. Chemical Characters. — Reference to the existence of specific ferments has been considered sufficient. Macrocytase, a tryptic * The cells in this disease are, however, pathological, and are not strictly classifiable in this list. The Large Mononuclear Leucocyte 185 ferment ; lipase, similar to that of the lymphocyte ; and oxydase (Winkler-Schultze granules) have been met with. The azur granules met with in this order of cells have excited much discussion among haematologists. On the one hand there is the inclination to look upon th^se particular granules as identical rather with the neutrophile granule of the polynuclear leucocyte than with the azur granule of the lymphocyte or leucocyloid lympho- cyte, and therefore the substrates for the oxydase reaction. The grounds for the belief are : 1. That ceUs lymphoid according to Romanowsky staining may show neutrophile granulation with triacid. 2. That the granules disappear from leucoblasts as the cell becomes oxyphUe and the specific granulation matures. 3. The monocytes found in leukaemia contain granules stainable %vith triacid. The objections to the view, on the other hand, are : 1. That Romanowsky does not stain immature neutrophile granulation at all well, because the basophilia of the cell-body masks it. A cell may thus appear lymphoid and yet belong to the true myeloic series (answer to argument i). 2. Neutrophile granules may exist side by side with azur granules. 3. The leukasmic monocytes are not lymphatic — are not lympholeucoc5rtes (answer to argument 3). 4. Azur granulation of the monocyte is a particular kind of material unlike that of either the lymphocyte or the myeloblast, because : (a) Its staining reaction is different ; (6) The granules are larger. 5. Pappenheim found azur granules in monocytes of animals which have no neutrophile leucocytes at all (amphibia, e.g.). Intracellular Origin of the Azur Granule. — H5mek66 suggested that the azur granule was a detached fragment of the nuclear substance, a chromidial displacement, upon which the azur material deposits, just as a fragment of organic matter might form the nucleus of a prostatic calculus. He believed that the neutrophile granule was deposited over the azurophile matter, rendering the latter invisible. Pappenheim considers that the effusion of 186 Biology of the Blood-cells chromidial substance disappears in the leucoblastic monocytes as the neutrophile granules appear, being only evidence of a certain functional state of the cell. A network of azurophile nodes also occurs in the cell-bodies of carcinoma-cells and in plasma-cells. Nay, more, every cell may show these granules if carefully studied, because azurophilia, in the opinion of the observer quoted, is merely a biological sign post of the existence of metabolic interchange between cell-plasm and nucleus. The existence of lipoid granules was established for the cell under consideration by Ciaccio.e? Comparative Cytology of the Large Mononuclear Leucocyte. — The large mononuclear leucocyte appears to be widely distributed, appearing as it does in the blood of all animals in which blood-cells can be detected. The formative organs are not always easily identified. In the crustaceans, mysis for instance, there is a structure in the dorsal cephalic region of the cephalothorax,^^ in relation to the stomach, formed of groups of cells separated by fibrillae. Division actively takes place in these clusters. According to the researches of Metchnikoff, ^^ the existence of a function- ally similar cell appears to go very far back in the animal scale. The mesen- chymal tissue of the lowest invertebrates includes cells which play the part of phagocytes, and are in every way analogous to the large mononuclear leucocyte of man. The presence of foreign bodies in the tissues of such animals, for instance, leads to the congregation of mesenchymal cells around the particle. A certain degree of selection is noticeable as to which foreign body is to be regarded as available for food, and which not. The classical investigations on actinia, showing the part played by these mesenchymal cells in the life-history of those metazoa, are of interest in this connection. In some of the fish^' the tissue analogous to the spleen is embedded in the substance of the kidney. Thus, the carp derives its large mononuclear leucocytes from such a renal tissue. In sharks a definite formative organ exists, which gives rise to numbers of macrophages. Teleosteans show definite pulpar tissue, and the vaguely suggested Malpighian bodies are found to be full of phagocytes. While large mononuclears are met with in the spleen of triton (a newt), the main function consists in erythrolysis, and the follicles disappear from the organ as age progresses. In this animal Mestral'" noted a remarkable periodicity of activity of blood-destruction, the organ being very vascular at one time, and ischaemic at others. Even in amphibia there is no definite association between the splenic tissue and monocytogenesis (Maximow'^), but in birds in the embryonic period it has been noticed by Jolly'^ that a period arises in which large mononuclears appear, apparently as a transitional stage in a myeloid metaplasia with final neutrophile leucocyte formation. The Large Mononuclear Leucocyte 187 The morphological characters of this class of cells when traced through the animal scale, also show several features of interest. In the first place there is no parallelism between differentiation of the blood-cell formula and the scale according to evolution. In some of the fish the large mononuclears do duty for the mammalian polynuclear leucocjrte, while in amphibia and reptiles they appear to play the same part as the macrophages of the higher vertebrates, and while poly- morphonuclear cells are absent, eosinophiles are an important feature of the blood. In carassius" there are three forms of lympholeucocyte — a vacuolated form, with feebly basophile cjrtoplasm and excentrically-situated nucleus ; a basophile form, with a nucleus of rather polymorphous shape containing two nucleoli ; and a myeloblastic form, with a nucleus presenting features in common with those of the myeloblast. The cell is usually conspicuously large in the tinea, leuciscus, and anguUla. In the perch it shows a well-marked astrosphere. In the cod, the cell-body is relatively large, and the nucleus is tucked in one corner of the cell. The cytoplasm shows a faintly-webbed structure. Speaking broadly, there are two forms of lympholeucocyte in the fish — one which is feebly basophile, and the other amphochromatic. Werzberg believes the last-named to be the precursors of the granulocjrte in these verte- brates. In the amphibia the blood appears less differentiated than in the fish, and the lympholeucocytes are rather numerous. Some of them show an oxyphile cytoplasm. Azur granules are frequently noticed (especially bombinator). An astrosphere is described as present in many instances. The lympholeucocytes of the frog vary in size, and have a characteristic marking of the cytoplasm. The nucleus stains feebly, and is almost like the lymphoidocyte in structure. As met with in the reptiles, they are found to have peculiar nuclear markings, owing to the presence of small angular discrete spots having a staining reaction like nucleoli (so-called pyrenoid marking). Some of the cells have a feebly basophile cytoplasm, and such forms contain either reni- form nuclei (tortoise, lizard), or horseshoe forms (grass-snake, ophiosaurus), or polymorphous nuclei (lacerta, anolis) . Others have a feebly amphophile cell-body, apparently a later stage than the preceding. In the chameleon these cells are unusually large. In acanthodactylus there is a form of lympholeucocjrte whose cytoplasm is mottled with azuro- phile marking. In agama some of the cells show a well-marked astrosphere. In the birds the lympholeucocytes have a feebly basophile cytoplasm, which is usually almost filled with the rounded nucleus, whose structure is myelocytar rather than lymphocytar. Occasionally indentations are met with, and a clear perinuclear halo may be made out. Such cells were found in the blood of the Senegal finch by Hirschfeld-Kossmann.'* Kasarinofif'* found that administration of haemolytic poisons led to the appearance of pathological monocytes in the blood. 188 Biology of the Blood-cells The Fate of the Large Mononuclear Leucocyte. — As has been shown, the function of the cell-form under consideration is best exerted in those parts of the body where the circulation is specially slow. It may be, therefore, that its occurrence in the blood is more of secondary interest, and its fate — in relation to the blood-stream — may be nothing more than immigration into the honeycombed recesses of the pulpar tissues. In these situations it is enabled to exercise its powers of sluggish movement incidental to the absorp- tion of particles with much greater facility than can be possible in the rapidly-flowing blood of the main channels. Having become detached from the trabecular network, it is swept along, by the blood-current to the pulpar tissue of some other part of the body, much as a mollusc which had loosened itself from a rock might be washed away to a far-off part of the coast. It is accordingly more satisfactory to discuss the fate of the cell under the heading of the pulpar cell itself. The ultimate conversion of this cell-form into a transitional cell has already been considered, and it has been pointed out that this stage represents the end-product of the particular line of develop- ment. The transitional cell may presumably pass through catabolic changes culminating in its disappearance as an entity, but of such phenomena we have no certain data. The lamellation of the edges, the formation of pedunculated buds of cytoplasm, loss of round contour, scattering of chromatin towards the edges of the cell, are all to be seen in blood-films from time to time. The change into the so-called irritation-cell may also be noted at this point. The essential feature of this change is the great increase of basophilia of the cell-body. After passing hack into the tissue-spaces the cell may settle down again, and undergo any of the cytoplasias presently to be described. In making this statement, it is assumed that the returning monocyte manifests the phenomena discernible in relation to the pulpar cell. Ceasing to be locomobile in the perivascular spaces, it gives rise to other cell-forms, provided that the necessary stimuli to cytoplasia be present. The Pulpar Cell and its Gytoplasias 189 III.— THE PULPAR CELL AND ITS CYTOPLASIAS. The morphology of the pulpar cell — It is a multi-potential cell — Its relation to the lymphoid follicles and to myeloid metaplasia — Genetic inter-relations — Chart representing these, and summarizing the essential features of the biology of the cells referred to in this and the preceding chapter. Were the term splenocyte a correct one to apply to the large mononuclear leucocyte ot the blood-stream, its development would be conveniently described as a splenoblastic line of develop- ment. As has been seen, however, it is misleading to take up the subject in that manner, and it becomes more effective to discuss the pulpar cell in a general sense, and regard the circulating monocyte as less important than the (relatively) sessile cell. The pulpar cell may be looked on as the mother cell of the monocytar forms, the pulpar tissue being the factory or birth-place (and perhaps also the cemetery) of these organisms. The embryology of the pulpar tissue is rather of secondary importance. The spleen-cells proper are carrying on the same work in the adult as they do in later embryonic life, save that there is some erythropoiesis in the embryo. The Morphology of the Pulpar Cell. — The pulpar cell is of variable size, measuring up to about 20 /« in diameter. It has a relatively large cell-body, and a large nucleus whose structure is ill-defined and feebly basophile (Plate VI). The cell-body itself is occasionally granular, some of these being azur and others phenolphilic. The former vary somewhat in size according to the type of cell, since there is a difference between myeloic azur granules and lymphatic azur granulation. The cell-body is basophile to a varying extent, especially at its periphery. Nucleus. — This varies in type, being usually lymphoidocytar, and includes one or two nucleoli. The structure is delicate or leptochromatic, owing to the absence of nodal intersections (in film preparations) and the feeble distinction between chromatin and parachromatin. In other examples the nucleus possesses characters which stamp it as lymphoblastic ; these have already been described. 190 Biology of the Blood-cells EXPLANATION OF PLATE VI. 1. — Juvenile large mononuclear leucoctye, after Benjamin (Fol. haem. Bd. vii., Plate IV). 2-5. — Various forms of splenic pulpar cell (Splenic film from a case of ruptured aneurysm) . 6. — ^Transitional cell with azur granules ; a senile form of large mononuclear. 7. — Leucocytoid large mononuclear leucocyte with azur granules. (This and preceding, after Benjamin). 8, 9. — Large mononuclear leucocytes from human blood. 10. — ^Transi- tional cell. 1 1 . — Polynuclear monocyte — metamyelocyte without neutrophile granules. 12-14. — Follicular lymphocytes from the spleen. 15, 16. — Lymphoidocytar splenic cells, showing coarse myeloic azur granulation. 17. — Typical lymphoidocyte from the splenic pulp. 18. — Plasmoid form of splenic microlymphoidocyte. 19, 20. — Erythrophages, phagoctyic leucoblasts. 20. — Nucleophage. 21. — Macrophage of spleen containing poly- nuclear cell (8-21 after Paremusoff, Fol. hsem. Bd. xii., Plates VIII-X). 22. — Degenerate form of pulpar cell (vacuoles in cell-body and nucleus) from a splenic film in a case of typhoid fever ; dying pulpar cell. 23-29. — Large mononuclear leucocytes (lympholeucocytes) from lower animals (23-28 from Werzberg, Fol. haem. Bd. xi., 29 from Kasarinoff, Fol. haem. Bd. X.). 23. — Salamandra maculosa. 24. — Rana temporaria. 25. — Emys lutaria. 26. — Lacerta viridis. 27. — Gadus lota. 28. — ^Anguilla vulgaris. 29. — Fowl. Stain, " Panoptic " throughout, except 7, which is " Jenner." Magnification, oil-immersion, oc 18. PLATE VI. THE LARGE MONONUCLEAR LEUCOCYTE "Cf^ i'ys «#^ i€^ m '^•' '";& Biulogv 0/ Blood-cdii O. C. Gruner The Pulpar Cell and its Gytoplasias 191 Nucleolus. — More than one, occupying varying positions in the cell, and possessing the usual chemical characters of such bodies. Mitosis is easily observed in tissue-sections. Variations According to Age. — The varying amount of cell-body possessed by these cells enables them to be classed as juvenile (so- called naked forms), adult, and senile forms. The latter have a relatively large cell-body (" endothelioid aspect "). This classifica- tion is in accordance with Heidenhain's law. The main interest of the pulpar cell lies in the cytometaplastic properties possessed by it. As has been indicated, it may pass along lines which tend to culminate in polynuclear leucocytes, or, far more usually, along hues which culminate in the transitional cell of the blood-stream. It is, then, the cytometaplasias that need to be referred to in studying this ceU. It may be assumed that in the first instance the pulpar cell is really a wandering cell, derived, like all other blood-cells, from perithelium or adventitial cells of capillaries. At certain times the wandering cell becomes stationary, ceases to possess phagocytic properties, and submits to the influences which changes in composi- tion of the surrounding medium exerted upon it. In place of migration from point to point within the pulp-cords, it settles down as an essentially multipotential or indifferent cell. 1. It undergoes intranuclear changes, and divides, and gives rise to a progeny of lymphoid character, possessing active phago- cytic ' properties, swept into the lymph- or blood-stream as large mononuclear leucocytes.* 2. It acquires nuclear characters which place it with the lymphoblasts of the central parts of Malpighian follicles. After one or two generations, a true lymphoblastf appears, able to give rise to clusters of large lymphocytes in the neighbourhood of the main vessels. The fate of such a process lies in the ultimate exhaus- tion of proliferative activity and disappearance of the follicle. The exact reason for this almost certainly lies in the advent of malign * This explains their appearance in the lymph of the thoracic duct and in the splenic vein. t So-called lymphoblastic macrolymphocyte. The real nature of this cell was estab- lished by the researches of Paremsusofi" in working on laboratory animals. He observed phagocytic properties in this cell similar to those seen in undoubtedly lymphatic cells. 192 Biology of the Blood-cells influences from without, since paucity of follicular tissue in the spleen, in autopsy material, is noticed specially in association with other evidences of bacterial infection (e.g. bacillus aerogenes capsu- latus, Fig. 43). 3. It acquires nuclear characters which indicate leucoblastic change. This phenomenon may be very conspicuous, or instances of such change may be only occasional. The former type of case is spoken of as " myeloid metaplasia " (Fig. 44), and is frequently noticed under the influence of certain bacterial infections (t5T)hoid, diphtheria, etc.). It is worthy of note that this leucoblastic or myelopoietic tendency is only persisted in up to a certain point. Anti-auxetic influences appear to exist which prevent differenti- ation from proceeding further than the metamyelocyte stage of development. This phenomenon will be discussed later. The significance of the process may lie in an attempt by the organism to supply more antibodies than the paralyzed bone-marrow can afford.* The genetic relations of the pulpar cell to the other cells of the spleen are more clearly indicated in chart form. Part of the subject has been included with the chart of lymphopoiesis {Plate III), but the chart on the opposite page, representing the inter-relations between follicles and pulpar tissue, expresses the various points more clearly. * Hzemopoiesis. The formation of erythrocytes by the spleen occurs in the human embryo during the interval between the fourth and fifth days (Lifschitz"), after which date the process gradually ceases. Megakaryocytes increase in number during this period. From this time onward the pulp tissue is myeloid in character, and spleen films appear exactly like marrow films. "... pauciU' ol' follicular tissue of the spkcn is noticed in association witli bactciial infection ' (p. I9::)- Fig. 43.— Splenic Tissue in a case of Death from Infection by Dacillts Aerogenes Capsu- LATUS. The drawing shows almost comiilcte necrosis of the tissue, the dark round spots being tlie nnlv splecn cells left intact. Distinction between ftillicles and pulp is entire!}- lost. Innumerable bacilli crowd the tield. (Oc. 12, 7,1 iss Apo.-lirrim. 4 mm.). " I.ciicoblastic change is frequently,- noticed under the influence of certain bacterial infections (typhoid, diphtheria, etc.) " p. 192. Fig. 44. — Splenic Pulp in a .state of Myeloid Met.vplasia. (a) m_\-e]oc\-te ; {!>) nietani3-eliic_\-te ; (c) lymiihoblastic cell ; id) mesolymphocyte ; {c) microl\-mphocyte ; (/) pol\-nuclear leLicoc_\'te ; {^} normo- blast ; (//) red cell; li) dividin'.,' pl?.smoid cell. (Oc. 12, Zeiss Oil-iramersion). The Pulpar Cell and its Gytoplasias 193 Fig. 45.— Chart representing Inter-relations between Follicles and Pulpar Tissue. dS* @^ PATHOLOGICAL SLOOO ■ <^y^'>P!f^^'<: differentiation mthtutdmsfon f.,, ^^^kgj^g^^igto undergo plasmoid change - possMe or doubtful corrections „ • -j 1 = mitosis " " ° " " " " eosinoid change ^amitosis " " ■*+ " " " " mast cell change Explanation of Chart. 1. — Resting perithelia! cell. 2. — ^Wandering cell of Saxer (pyrrhol cell). 3. — Lym- phoidocyte. 4. — Lymphoprimitive cell. 5. — Splenic pulpar cell. 6. — Leucoblast. 7. — Lymphoblastic macrolymphocyte. 8. — Interfollicular cell. 9. — Micro-lymphoidocyte. 10. — Microleucoblast. 11. — Monocytoid macrophage. 12. — Lymphoma cell. 13. — Meso- lymphocyte. 14. — Microlymphocyte ; 14' Leucocytoid microlymphocyte. 15. — Schridde- Hodara plasma cell. 16. — Large mononuclear leucocyte. 17. — Transitional cell. 1 8. — Promyelocytar eosinophile cell ; 1 8 '. — a-micromyelocyte. 1 9. — Eosinophile cell. 20. — Mast cell. 21. — Senile leucoblast. 22. — Plasma cell. 23. — Older plasma cell. 24. — Lymphsemic lymphocyte. 25. — Rieder cell. 26. — Leukeemic monocytoid leucoblast. 27. — Megakaryocyte. 28. — Stroma cell. 29. — Fibroblast. 13 194 CHAPTER V. ON THE NEUTROPHILE LEUCOCYTE. Section I. — The Bone-Marrow as a White Cell Factory : The seat of manufacture of the neutrophile leucocyte — Graphic representation of varying states of activity of the marrow-tissue — MetaboHc changes in the adipose tissue of the bone-marrow — ^Autolytic changes — Meta- bolism in the bone-marrow cells — Accessory factories of leucopoiesis. Section II. — The Life-histoey of the Neutrophils Leucocyte UP TO THE Time of its Birth into the Blood-stream : Morphology of the cells of the myeloic series^ — Morphology of the leucoblast — The myeloblast — The promyelocyte — The myelocyte — The metamyelocyte — The leucoblastic line of development — Pappenheim's scheme — List of the cells normal to the blood and of those pathological to the blood — The birth of the neutrophile leucocyte into the blood-stream. Section III. — ^The Life-history of the Neutrophile Leucocyte in the Blood-stream : The morphological characters of the cell — ^Ameth's system — Schilling's modification — ^The functions of the cell — Chemical characters — ^The granules : neutrophilic, iodophilic, sudanophihc, phenoJ- philic, oxydase, myeloic azur — ^Theories relating to the nature of these granules — Ferments — Extractives — ^The death of the leucocyte — Pheno- mena in the cytoplasm, and in the nucleus — The comparative cytology of the neutrophile leucocyte. Section IV. — The Cytoplasias of the Leucopoietic Tissues. Leucocytosis : principles in white-cell counting ; causes of leuco- cytosis ; the phases of leucocytosis — Leucopenia — The hyperplastic and metaplastic processes of leucopoietic tissues : contrast between leukaemia and leucocytosis ; auxetic processes. Bone-Marrow as a White-cell Factory 195 I —BONE-MARROW AS A WHITE-CELL FACTORY. The seat of manufacture of the neutrophile leucocyte — Graphic representation of varying states of activity of the marrow-tissue — Metabohc changes in the adipose tissue of the bone-marrow — Autolytic changes — MetaboUsm in the bone-marrow cells — Accessory factories of leucopoiesis A DESCRIPTION has already been given of the structure of the bone- marrow in relation to erythropoiesis. It was pointed out that this tissue is built up round vascular channels which vary in size with variations in functional activity. As Virchowi expressed it, the marrow tissue is a persistent quasi-embryonic granulation tissue. The distribution of the arteries through the bone is well described by Carnegie Dickson^ (1908), who points out that the medullary artery of the shaft usually divides into two main divisions passing to each end of the bone. They become more and more central in position, and give off radial branches on their course. Accompanying the central artery is a large very thin-walled sinus, draining blood from numerous radial tributaries, which form free anastomoses with one another, and appear to form communications with the lymphatic spaces adjoining the marrow-cells. The opinion has been expressed that the leucoblastic cells are outside the capillary channels, while the red-cell-forming cells are intravascular, but there is no very definite evidence in favour of this supposition. The only difference in the structure of the marrow in different parts of the same bone lies in the relative preponderance of vascular channels in the central parts of the shaft and the relatively increased density of the connective-tissue reticulum towards the periphery or endosteum. It will be borne in mind that in man, the bony trabeculae are so apt to pass through the whole thickness of the bone that a distinction into zones (mapped out by Carnegie Dickson) fails to have much importance. As with the pulpar tissue, so with the marrow tissue, the theatre of action of haemopoiesis may be easily defined in terms of a microscopic field, such as was shown in Fig. 17. This would be some distance away from the centre of a marrow-space, where the 196 Biology of the Blood-cells blood-vessels are relatively more numerous than formative cells. Were the marrow-cells washed out, we should see a delicate reticular tissue formed of branching connective-tissue cells and fibrils, intermingled with the fat-cells already referred to. In other words, we have to deal with a fatty areolar tissue, amongst the meshes of which are more or less densely packed free- Blood. • Erythropoietic Tissue. Leucopoietic Tissue ^ Blood. / B / / / B -^ I I / r C / y ..' A 1 y' • / A A / / n -. I 1 / .. D ~~- --^ / / / / / / / ,--- D D — f A ~ '- ^^^^ __, .-; '" c ""■— -^v- N ^ ,/ /. B \ 'y ^ Fig, 46. — Graphic record of the cell-fonmila of the bone-marrow xinder different conditions, sdected from the writer's collection. A, Normal infant. B, Case of ulcerating carcinoma, with blood neutrophilia. C, Case of typhoid fever with leucopenia. D, Case of appendix pyaemia with moderate leucocytosis. — 1, Mother cell. 2, I.eucoblast. 3, Daughter leucoblast. i. Promyelocyte. 5. S', Mydocyte. 6, 6', Metamyelocyte. 7, Neutrophile leucocyte. 0, Erythroblast. * Erythroblasts only represented. floating cells of very various sizes and shapes. As was stated in dealing with the red-ceU factory, these cells belong to two orders — the red-cell-forming and the white-cell-forming, which are only identifiable when the tissue is examined with a very high power of the microscope. The broad points of distinction between these specific or proper marrow cells were indicated in connection with the red-cell parents, and their exact morphology is described in the Bone-Marrow as a White-cell Factory 197 ensuing section of this chapter. The various members of the white-cell-forming group do not always occur in the same propor- tions, but it is found possible to classify a given marrow tissue according to the preponderance of one or other of these cells. If smears be made from the marrow at autopsy, or during life (Ghedini-puncture of the tibia, for instance), and a differential count made, a cell-formula for the tissue may be drawn up, and used to make a graphic record somewhat in the manner shown in the figure opposite (Fig. 46). Here the length of the first ordinate represents the percentage of mother cells in the film, that of the second represents the percentage of leucoblasts, the abscissa being here made to commence at the apex of the first ordinate. The third point is found in the same manner, and represents the per- centage of cells belonging to the next stage of development. The other points are marked in as explained in the figure, till finally we come to a vertical line [x), which represents the barrier between tissue and blood-stream, and allows a demonstration of the relation between white-cell manufacture and neutrophile output. If the blood contains metamyelocytes, for instance, the vertical line would require to be placed more to the left in order that the blood- cell formula should include these immature cells. In such a case we have an example of Arneth's " deviation to the left." The figure shows four curves which demonstrate the effect on the marrow produced by infective agents of varying intensity or by certain forms of disease, the curve for the infant's marrow serving as a standard. The latter, rising as it does, regularly and continu- ously (i.e., a straight line), strikingly demonstrates the regular output of maturing cells into the marrow tissue. The curve D, on the other hand, taken from a case of appendix pyaemia, shows hardly any ascent of the line at all, whUe the height of ordinate i indicates the preponderance of parent cells in the tissue. Even the blood in this case shows only a moderate degree of leucocytosis — evidently the result of inadequacy on the part of the bone-marrow to supply the need for leucocytes in the affected areas of the body. The presence of adipose tissue is an important feature of the marrow. It constitutes a variable packing material, the absorption 198 Biology of the Blood-cells of which allows space for increased proliferative activity of the proper cells, while diminished activity on their part is responded to by an increase in the size of the fat cells {Fig. 47). Probably we have before us a co-ordinated action between the two types of tissue, the agent which causes alterations of metabolism on the side of the adipose cells also calling forth an alteration in the formative activity of the blood-cell parents. According to Maximow,i the fat cells of the bone-marrow are really fibroblasts. C. E. Walker ,3 working with axolotl, found that the purpose of some of the bone-marrow cells was merely to subserve the nutrition of other cells. A second group pass through many mitotic divisions to give rise to genera- tions of cells characterized by possessing only half the number of somatic chromosomes, and ultimately form the red cells. A third group, he thought, were fertilized by conjugation, and after dividing a number of times, produced the white cells. Metabolic Changes in the Adipose Tissue of the Bone- marrow. — The phenomena observed by Ciaccio* may be sum- marized as foUows : (i) Fragmentation of the fat-globule into two or more smaller fragments ; (2) An actual chemical trans- formation of the fat into a soluble derivative ; (3) The passage of this transformed fat across the lipoid-containing cuticle of the adipose cell, with (4) The deposit of protein substances in the vicinity of the cuticle ; (5) The replacement of the cell-substance of the fat-cell. The protein substances which are deposited are lipoid compounds exhibiting the property of staining with certain aniline dyes. They are soluble in feebly alkaline solutions, but not in water, alcohol, ether, chloroform, or acids (either acetic or mineral). Autolytic Changes in the Bone-marrow. — These are of considerable importance, and have been studied by preserving the marrow in a moist chamber for several days, and examining it at intervals.s Within three days' time, it is found that the inter- stitial tissue undergoes a gelatinous change, and is associated with lack of definition of the marrow-cells. The latter lose their granules, and the nuclear matter stains uniformly, without any visible differ- entiation of structure. As days pass on, the cells become less and less numerous, granules become entirely absent, and the nuclei 'lA. K !■*■ •i'^. ■■ . . . diminished acLi\"it\' un tlicir inivt " (Uic proper iiuiridw cells) " is respimik-d Id ]i\ an increase in tlic size of the iaL cells " (p. I'j^). Fic;. 47. --Atkophic Marriiu'. The i)hoto;,napli shows nnieh lar.^er spaces, «ilh ninch fewer cells bct«'cen Iheni than arc notieed in Fi<^. 17. (Oc. -I, Zeiss, Ohj. D), Fac,- /. /o.\'\ ■' The changes . . characteristic of gelatinous degeneration" (p. 199). Fii:.. 48. — " The fat spaces " (a) " are norma) in number, but the interstitial tissue between them is changed, having Inst many of the specific cells " (/') " and acquired a hyaline appearance " [c] ; [d] nieg.-Lkar\ric\tes. (Oc. 4, Obj. Apiichriim.) ". , . The field is seen to be flooded with granules from the breaking-down cells " (p. 109). /■"/;'. 40. — The various forms of marrow cell are here seen in various stages of degeneration. Contrast with Fi.^s. 50, si- (Oc. 18, Zeiss Oil immersion.) Bone-Marrow as a White-cell Factory 199 become fragmented, pass through an intermediate stage of hyper- chromatosis, and disappear. The changes are complete in about twelve days, and the picture is then similar to that characteristic of gelatinous degeneration (Fig. 48), met with especially in cases of inanition from any cause, a fact which indicates that this change is the result of autolytic ferments becoming liberated in such individuals, from one factor or another.* These phenomena strongly recall others which are sometimes noted in autopsies on the human subject. Routine examination of this material has shown the striking fact that sudden death occurring in the course of obscure affections^ without marked or gross lesions, is sometimes associated with marked autolytic changes in the marrow tissue {Fig. 49). In this case, the field is seen to be flooded with granules from the breaking-down cells ; many of the granules are neutrophile, but the majority are azurophUe granules from the leucoblasts and lymphoidocytar cells. It appears as if such a change, occurring during the last hours of life, might pre- cipitate a fatal result from sheer liberation of complement or other immune substances in excess of margins of safety, aided to the extreme by entire stoppage of red- and white-ceU production. LucibeUi'' found that similar changes in the rabbit bone- marrow are induced by fatal injections of typhoid, colon, and paratyphoid bacilli (loss of staining power of cell, swelling of nucleus, irregular distribution' of chromatin, folding of the nuclear membrane, karyolysis). Changes analogous to these were described by Longcope in cases of experimental staphylococcic infection.^ Metabolism in the Bone-marrow Cells.— Just as the fatty tissue of the bone-marrow presents variations of metabolic activity which are recognizable by the aid of histological methods, so the blood-forming cells can be demonstrated to undergo meta- bolic changes which are chiefly manifested by variations of the • In gelatinous degeneration the fat spaces are normal in number, but the interstitia tissue between them is changed, having lost many of the specific cells and acquired a hyaline appearance. The change may be focal or diffuse, and may be associated with atrophy of the cancellous bone, or may occur as an almost imperceptible change amongst the fine- meshed trabecule of a rather ossified marrow cavity. It may or may not be associated with disseminated foci of formative or fatty marrow. This form is not identifiable in film preparations. It occurs in diseases associated with starvation, prolonged diarrhoea, carci- norna or prolonged cases of suppuration. Foa, in 1905, found that the normal blood- serum of other species of animals would have the same effect on the marrow. 200 Biology of the Blood-cells lecithin content. Ciaccio^ noticed that a lecithin-nucleo-proteid compound is abundant in these cells, and therefore called them cellules lipo-proteo-boliques. The deposition of such material, which is derived from the nucleus, is anabolic in character. As the lecithin increases in amount, material comes to be at hand which is necessary for the development of the myeloid ceUs into a granulocyte progeny— a fact which throws light on the ultimate nature of the agent clinically responsible for an increase or inhibition of a leuco- blastic reaction in the marrow. These points must be appreciated in order to understand correctly what is going on in the bone-marrow at any given time. The cells are sometimes resting and sometimes active, just as are the gland-cells of a secretory organ. When resting, the cytoplasm is ill-defined because of the accumulation within it of metabolic (anaboHc) products, whereas the active cell contains pigment d6bris, etc., and has a smaller nucleus. A further feature of the metaboHc process lies in the appearance of oxydase ferment within the cells. This is connected physically with the nucleo-proteid constituents of the cell, although it cannot be said to be dependent on such a material, because lymphocjrtes do not contain oxydative ferment, and yet the nucleins are identical.i° While the most obvious effects of metabolic processes on morphology are most satisfactorily demonstrated when dealing with the development of erythrocytes, a similar sequence of visible changes may be traced in connection with the myeloid series of cells.* The passage of material from the nucleus into the ceU-body and its transformation in this new position into other substances, account for alterations of nuclear structure, just as the passage of material out of the nucleus of the normoblast leads to the loss of parachromatin, condensation of chromatin, and the formation of a very deeply stainable shrivelled polymorphous or " pycnotic " nucleus. It is further helpful to remember that the cells are subjected to different stimuli even during the course of a physiological process, * The term myeloid is conveniently applied to the group whose terminal stages are cumbered with the name polymorphonuclear leucocyte. '■ The fonnative cells are seen to be of various t\'pes (p. 45). Fig. 50. — IMarrow Film.— Harrow leucocytes, seen with the oil-immersion. There are five eosino- philic myelocytes, one basophilic myelocyte, four nucleated reds (one pycnotic), two free nuclei, and six metamyelocytes. Numerous red corpuscles and a few indifferent marrow lymphoc^'tes lie in the field. '• . . . a leucoblastic reaction in the marrow " (p. zoo). Fig. 51. — Marrow Film. — The prevailing cell-foim is a myelocyte with fine nentrophile granula- tion. Note also the uninuclear indifferent marrow cells. Face p. 200] Bone- Marrow as a White-cell Factory 201 and that the phenomena of cellular metaplasia arise in this way. As has been the theme in previous chapters, alterations of meta- bolism leading to deviations from the original line of development are the explanation of a condition of metaplasia in the cell, which is manifested in the tissue as a whole by the formation of a number of cells of a type different from that usually seen. Whereas in the spleen it is more usual to find the splenoblastic line followed to its extreme, so in the bone-marrow, the myeloblastic line (the one natural to that tissue) is usually followed. Accordingly, meta- plastic change in the former comes to be manifested in what is termed myeloid metaplasia, whilst in the latter the metaplastic change is recognizable as a lymphadenoid change — to instance isolated examples. Again, it does not follow that bone-marrow, left to itself, is always likely to produce erythrocytes and myeloid ceUs in just proportions. Everything, or much, depends on the presence of a suitable incoming stimulus. If myeloid cells are to be continuously produced, there must be a myeloplastic stimulus (a hormone) always available, just as the brain would cease to be conscious if it were not continuously receiving sensory stimuli from without. It is only by a conception of this kind that the remarkable sudden- ness of leukaemia can be intelhgible. Nevertheless, we cannot shift the responsibility of successful myelogenesis entirely upon incoming stimuli ; an internal predisposition to differentiate on such lines must be assumed. The phylogeny may be to a certain extent predetermined. The effect of such a simple agent as absence of food is instruc- tive in this connection. Dtiring fasting, the myelocytes are more abundant than poljmuclear leucocytes;" but after taking in of food, the reverse holds good — the tissue becomes very vascular, intermediate or transitional forms between myelocytes and neutro- philes become very numerous, and the myelocytes inconspicuous. The megakaryocytes remain unaltered, save for the occurrence of included neutrophile leucocytes. X-rays have been found to produce a disappearance of fat from the adipose cells, concomitantly with a marked hyperplasia of the leucoblastic formative cells. Not only is the absolute number 202 Biology of the Blood-cells of myelocytes increased and abundance of mitotic figures noticeable, but the number of mature leucocytes in the tissue is very strikingly augmented. Eosinophile and mast-cell types also become incon- spicuous.i2 Accessory Factories of Leucopoiesis. — Bone with marrow spaces in it has been described as arising anew in certain of the internal organs. Thus Bilamioni found an inclusion in the lower lobe of a rabbit's lung related to the pulmonary artery. He con- sidered the finding as evidence of the possibility of embolism of hemopoietic tissue into the spleen, etc., from other organs. Other observers have found new bone arising in the kidney and other viscera. Such new marrow-tissue must, however, be looked upon as an anomaly, as there is no collateral evidence that it is performing a necessary part in the economy. Life-History of the Neutrophile Leucocyte 203 II.— THE LIFE-HISTORY OF THE NEUTROPHILE LEUCOCYTE UP TO THE TIME OF ITS BIRTH INTO THE BLOOD-STREAM. Morphology of the cells of the myeloic series — Morphology of the leucoblast — The myeloblast — ^The promyelocyte — The myelocyte — The metamyelocyte — The leucoblastic line of development — Pappenheim's scheme — ^List of the cells normal to the blood and of those pathological to the blood — The birth of the neutrophile leucocjrte into the blood-stream. Morphology of the Cells of the Myeloic Series. — The cells of the myeloic series are conveniently considered in the order of their development. Since all these cells are studied in film prepara- tions of the marrow, their description will be found to cover that of the parenchymal cells of marrow-tissue as they appear with the oil- immersion lens. It is convenient to divide these cells into groups according as they possess specific granules or not. The former are immediately concerned with the birth of the leucocyte, the latter are more remote ancestors. The -parent cell, or lymphoidocyte, has already been dealt with at length {Chap. I), and it has been pointed out that it exists in two forms — the macro- and the microlymphoidoc5rte. In each case the nucleus is extremely finely meshed, and apparently finely granular in structure, while one or more nucleoli are constant (Fig. 52). A senile change in such cells, whereby the cell body becomes enlarged and the nucleus relatively smaller, is not a usual ^*^- ^^'■ •^ Diagram of structure finding, and if noticed — ^whether in the tissue °' ^^ lymphoidocyte. film or in leukaemic blood — may be looked on as pathological. Similar remarks may be applied to forms with deeply indented and polymorphous nuclei, or Rieder forms. Morphology of the Leucoblast. — ^The only other myeloid cells which may have no granules are the leucoblasts, already referred to as "leucoblastic monocytes," and these cells present the following morphology {Fig. 40). — 204 Biology of the Blood-cells Shape — oval. Size — large. Cell-body. — Strongly basophile in reaction, the basophilia being uniform throughout. There is definite fibrillation of structure, especially towards the edge, which is accordingly rather ill-defined. The paraplasm is definitely oxyphile, and contains numerous azur granules of myeloic type. The more oxyphile the cell becomes the more amphochromophile does it appear (contrast with the poly- chromatophdlia of the erythroblast). Nucleus. — Round, indent, or polymorphous in shape. The structure is typical. The chromatin threads are not as broad as the parachromatin, and the appearance of transveise bands forms an easy means of identification. A circumnuclear zone is often absent, but an astrosphere is usually easily identified. Nucleoli are absent. The daughter generation of the leucoblast is called the MiCRO- LEUcoBLAST. This cell also has a basophile cytoplasm, though the basophilia is less in degree. The paraplasm is oxyphile. This cell is analogous to the microlymphoidocyte, like it being of smaller size than the parent. Sometimes an intermediate form can be distinguished — the Mesoleucoblast, whose cytoplasm is pale blue and rather rich in spongioplasm. The nucleus is slightly indented and shows very distinct transverse shadowing. The only other respect in which it differs from the leucoblast is in point of size. It is possible to subdivide the leucoblasts into as many groups again, according as they contain azur granules or not — it being always remembered that the mere presence or absence of such does not create a new cell, but merely indicates the existence of a certain state of functional activity. If the findings referred to in connection with lymphocytes hold good here also, we should assume that the leucoblasts without azur granules are probably younger than those with them. The azur granules are coarse, more numerous, and more uniformly scattered through the cell- body than holds in the case of lymphoid cells, and axe of a bluish-violet colour.is As seen in sections, the leucoblast appears to have rather a Life-History of the Neutrophile Leucocyte 205 vesicular amblychromatic' nucleus, and contains one to three nucleoli. Some of the " indifferent marrow-cells " are leuco- blasts. With increasing age, the leucoblast conforms to the same law as is found in the case of the other blood-cells. It is possible to divide each of the six forms of leucoblast into as many more by classifying them into mature and senile (leucocytoid) forms. The senile forms are characterized by a relatively abundant cytoplasm. Pathologically, the senile change may be carried so far that we have actually a polymorphonuclear leucoblast, which only differs from the normal mature neutrophile leucocyte in possessing no neutro- phile granules. Ordinarily, the fate of the leucoblast is to differentiate into a promyelocyte. Differential Diagnosis. — Since promyelocytes may show very few, if any, specific neutrophile granules (the distinctive feature being solely a decided oxyphilia of cytoplasm), they are liable to be erroneously classified with the non-granular cells (azur granules do not count). It is possible, however, to avoid confusing the cells by noting the structure of the nucleus. If this be myelocytar in type, the cells would be correctly placed. The Myeloblast. — ^This cell was so named by Naegeli, being regarded by him as the ancestor of the polynuclear leucocyte alone. The invention of the term " lymphoblast," on the other hand, led to the discussion of the identity or not of these two cells. The difference between the two has been referred to as indefinite (Chap. I), though emphasized by the dualists. The myeloblast of Naegeli does not actually correspond to the leucoblast of Pappenheim, but includes two kinds of cells which are really different gener- ations of the primordial cell. Further confusion has arisen in that different authors use the word " myeloblast " to express different cells. Thus Helly^* came to the conclusion that the myeloblast was really the parent of red cells, at any rate in post- embryonic life, because : (i) Myeloblasts are very densely aggregated round erythroblast foci in cases of severe ansemia, instead of lying loose in the reticular tissue ; (2) The conditions met with in leukaemia are no criterion, because they are entirely pathological. The answers to these statements are : (a) That Helly's myeloblast is not the same as Naegeli's ; (6) The red-cell parent has a trachychromatic nucleus, whUe the myeloid parent has an amblychromatic nucleus ; (c) There is a protometrocyte present in selacians which gives rise to cells with amblychromatic nuclei at one time, and cells with trachychromatic nuclei at another, and has no lipoid substances within its body.i^ 206 Biology of the Blood-cells The characters of the myeloblast, as given by Naegeh, are {Fig. 12) : — Shape, oval. Cell-body very basophile, devoid of granules. Cytoplasm has a foamy structure. Nucleus oval, and nearly as large as the cell-body, rich in chromatin, which has a delicate structure and is limited by a delicate nuclear membrane. There are no azur or fuchsinophile granules. Three or four nucleoli can be seen. Mitotic figures are extremely rare. The myeloblast of Schridde, as seen in the tissues, differs rather from the above, but chiefly in being occupied by pigment granules or leucocytes till it reaches a diameter of 20-40 ju. Tsunota states that it is frequently seen in inflamed appendix tissue. ^^ The Promyelocyte. — The next stage of development of the leucoblast is the promyelocyte. This is the immediate precursor of the myelocyte, and is characterized chiefly by the halfway con- dition of its cytoplasm in the direction of oxyphUia, and the first appearance within its body of neutrophilic granules. These appear as very fine punctations in the vicinity of the astrosphere, which is pushed aside as they accumulate,! « while the nucleus becomes richer in chromatin and the nucleolus diminishes in size {Fig. 53). ^»f. 53. — ^, promyelocyte; b, c, myelocytes showing varying nuclear markings. Note the commencing oxyphilia (pink stippling), and the azur granules (piij£) in the promy^ocyte. The cell is smaller than the leucoblast, but the other characters need not be detailed. Variants of this cell also occur, just as holds in the case of the preceding cells — senile change, undue polymor- phism of nucleus, degenerative changes. Undue polymorphism of nucleus gives rise to the appearance of an immature or precocious poljmuclear leucocyte, whose cell-body is only incompletely oxy- phile. Such a cell is liable to be mistaken for a pycnotic megaloblast or for a true leucocyte. A MiCROPROMYELOCYTE has been described, which has an amphochromophUe cell-body, with an indented trachychromatic pachychromatic nucleus. Myeloic azur granulation is still present. Life-History of the Neutrophile Leucocyte 207 The promyelocyte is a preponderant cell, according to Lossen," in the marrow of children affected with bronchopneumonia, tuberculosis, and measles ; in such cases the neutrophils are diminished. The Myelocyte. — Further differentiation of the cell converts the promyelocyte into the myelocyte, a cell well known to haemat- ology owing to its characteristic presence in leuksemic blood. Until recent times it has been looked on almost as the only form of abnormal cell that could occur in the blood-stream. The characters of the (mother) myelocyte are (Fig. 53) : — Shape. — Rounded or ovoid. Size. — 10-20 /i. Cell-body. — Shows only a trace of basophilia. There is a finely reticular structure. Oxyphile or neutrophile granules have appeared, and lie chiefly towards the periphery of the cell. An astrosphere is plainly seen in some examples. Nucleus. — Large, round, or oval, or slightly indented. There is a well-defined nuclear network, forming bands alternating with parachromatin. The nuclear membrane is sharply marked off. Nucleolus absent. Appearances with Vital Staining [Plate VII., 54-62). — The nucleus remains hardly coloured so long as the cell lives, but a variable number of dancing blue particles can be seen in the cell- body. Functions. — Phagocytic, when not mitosing or differentiating.* Fate of the Myelocyte. — The natural sequence of changes which take place in the myelocyte is that which leads to its conver- sion into a metamyelocyte. The proof that myelocytes are pre- cursors of neutrophiles lies in the absence of lesions anywhere else than among these cells in cases of infective leucocytosis ; also the fact that drugs which set up leucocytosis (bitters, ethereal oils, camphor, blood poisons, etc.) also lead to the same phenomena in the bone-marrow. This cell may undergo senile change, coming to have a relatively * That they are not locomobile, and cannot make their way through the blood-vessels in the same manner as polynuclear leucocytes, is shown in the observation that only poly- nuclear leucocytes enter the suppurating focus when inflammation with pus formation occurs in the course of leukaemia. In new-born infants, too, the inflammatory cell infiltra- tion never contains myelocytes, although such cells are present in the blood at that time of life. 2 » 208 Biology of the Blood-cells small nucleus, but ordinarily its tendency is towiards polymorphism of the latter, and the production first of a metamyelocyte, and ulti- mately a true neutrophile leucocyte. Under abnormal influences, however, degenerative changes may appear, which may be summar- ized as follows : (i) Condensation of the chromatin into small masses situated immediately within the nuclear membrane ; (2) Swelling and vacuolation of the nucleus ; (3) Diffusion of the chromatin from the nucleus into the cell -body, with Hi-definition of the nucleus ; (4) Rupture of the nuclear membrane, with disappearance of the nuclear matter; (5) Swelling of the cytoplasm, with increased staining reaction of the spongioplasm, so that the cell body appears more granular ; (6) Vacuolation of the cell-body, spaces of variable size appearing. The later the change the larger the vacuoles, until finally only a skeleton of the cell remains ; (7) Complete fragmenta- tion of the cells.19 Although the myelocyte does not appear in the blood-stream until it has differentiated into a neutrophile leucocyte, there are circumstances which lead to its premature entry into the circula- tion : (i) In association with polynucleosis occurring in infections, notably diphtheria : the bone-marrow is then hyperplastic and hyperaemic ; (2) In association with anaemias, notably pernicious anaemia, von Jaksch's anaemia, syphilis, rickets, anaemia from neoplasm ; (3) Without associated changes in the differential count in uraemia, acute mania, and in diseases with an asphyxial condition of the blood ; (4) During the course of pregnancy (Blumenthal22). Jagic's suggestion's that some myelocytes cease to differentiate, but gradually lose their granules and finally enter the blood as large mononuclear leucocytes, may be dismissed as quite improbable. Multiplication without Differentiation. — A smaller form of myelocyte was described by Pappenheim, and named micro- myelocyte by him. The characters of this ceU resemble those of the parent, the distinction lying in the size of the cell. The MetamyelocYte. — This is a further stage of development of the myelocyte or micromyelocyte. Its characters are easily •defined, as it resembles the transitional cell already described, save that it has an oxyphile cell-body and bright neutrophilic granules Life-History of the Neutrophile Leucocyte 209 scattered through its substance. The nucleus stains more strongly and shows characteristic chromatin markings. Atypical forms, however, have been described : (a) Forms with a basophile cytoplasm, producing a close resemblance to the transitional cell ; (&) With an oxyphile cell-body but no specific granules ; (c) Dwarf forms ; {d) Eosinophile forms, when found, may perhaps be only functional variants from the main type. There are reasons for looking on all eosinophiles as variants. The Leucoblastic Line of Development. — Starting with the primoroial cell, the changes which take place in it may be described according to the same plan already adopted for the other series. The primordial cell is multivalent. This strongly basophile cell, with a large rounded nucleus, whose markings are characteristic, and may or may not present azur granules, undergoes a nuclear change which impresses on it the characters of the leucoblast. Here the markings of the nucleus are those peculiar to the myelocyte : transverse shadowing becoming more and more intense until the shades appear as deeply-staining streaks or lines. This cell divides and gives rise to the promyelocyte, where a commencing acidophilia of the cell-body becomes discernible, and a few scattered neutrophile granules begin to appear side by side with the azur granules (when such are present). The promyelocyte may differentiate with or without division. The succeeding stage is a myelocyte which either divides or merely differentiates into the metamyelocyte and then into the familar neutrophile leucocyte. Blumenthal24 believes that most of the phenomena noticeable within the myelocyte nucleus during its evolution into polynuclears are explicable as the result of : (i) Osmotic influences ; (2) Increas- ing deposition of granules within the cell-body. The more granules, the more incurved does the nucleus become, until, little by little, the pol5niuclearity is assumed. Once the leucocyte- reaches the blood, the difference of osmotic pressure in the serum from that in the marrow-tissue allows some plasmolysis to occur, and deformity of the nucleus results. This would explain the paucity with which polynuclears are met with in the marrow-tissue itself. The very means of entry of the myelocytar cell into the blood-channel is 14 210 Biology of the Blood-cells explained on physical principles by Errera^s as a surface-tension phenomenon ; the change of chemical structure acting on one part of the leucocyte causes it to throw out a pseudopodium through the demarcating membrane, and so attracts it into the correct direction. The natural line of development, then, is along the successive stages dealt with in this section. We find, however, that differentia- tion may become inhibited at any time, so that leucocytoid forms of any type may come to be an end-point of development. Patho- logical polymorphosis of the nucleus without other signs of maturity manifests the existence of influences adverse to normal differentia- tion, and gives rise to a bizarre picture of the tissue under consider- ation. Fig. 54. — Diagram Representing Some of the Cells of the Myeloic Series. (1) Myeloblast ; !f) Micromyeloblast ; (S) Mesoleucoblast ; (U) Microleucoblast ; (5) Mydomonocyte ; (6) Micromyelocyte ; (7) Metamyelocyte; (S) Polynudear leucocyte. The purple stippling indicates basophilia of cell-body, the pink stippling indicates deftoite oxyphilia of cell-body. The varying nuclear markings show certain types encountered ; they are purposdy drawn distinctly, whereas in the actual nudei they appear as shadowings. The black dots represent azur granules, the red ones neutrophile granules. Pappenheim's Scheme of the Development of the Neutro- phile LeucocYte is as follows : — Lymphoidocyte Meso- lymphoidocyte Micro- -^ lymphoidocjrte ■ leucoblast (myelo- monocyte) meso- leucoblast \ micro- leucoblast -> pro- --> myelocyte I I ->■ meso- promyelocyte i *■ micro- —■ promyelocyte myelocyte J- meso- myeloc5rte micro- myelocjrte senile mother myelocjrte -^ senile myelocyte ■^ meta- myelocyte I neutrophile leucoc3rte Life-History of the Neutrophile Leucocyte 211 Or, demonstrating the metamorphoses taking place at the same time : — Lymphoidocyte (strongly basophile, specific nucleus, facultative azur granulation) Leucoblast (less basophile, nucleus myelocytar, facultative azur granulation nucleolus) V becomes senile by swell ing of cell-body, and dimpling of nucleus. become senile, nucleus deeply dimpled. becomes polynuclear without other differen- tiation. becomes polynuclear without other change. Mesoleucoblast (A smaller cell, well marked shadowing of nucleus, no nucleoli) i Promyelocyte [Cell-body as of lymphoid cell ; neutrophile granules (partly from cytoplasm, partly from nucleus) azur granules also] Mother myelocjrte Cell-body has oxyphile reaction Mesomyelocyte ^^ ^^.^^ I into two Daughter or micro-myelocyte ages into 4, 4, Polynuclear metamyelocyte (horse-shoe nucleus) turns into ■^ Polymorphonuclear leucocyte. At this stage it will be convenient to tabulate the cells which are normal, and those which are only found pathologically, in the circulating blood. Cells Strictly Normal to the Blood. — Neutrophile polynuclears. Eosinophile polynuclears (different forms). Facultatively Normal. — Neutrophile metamyelocytes. Cells Pathological to the Blood.— A. Variants of the Mature Cell — ■ Degenerative forms : — Fatty neutrophiles.* Caryorrhectic forms (with 5 or more segments). Vacuolated forms. • Detected with Sudan III. Seen in septic inflammations. 212 Biology of the Blood-cells Eosinophile metamyelocyte. Giant neutrophile polynuclear (10-12 fx in diameter). Giant eosinophile cell with active amoeboid and phagocytic pro- perties. Neutrophiles with altered staining reaction of the granules or nuclei. Unduly fragile neutrophiles (easily damaged in making films). Atypical forms : — Polynuclear cells with granules but basophile cell-body. Non-granular polynuclears with oxyphile cell-body.* Dwarf forms. Giant forms (seen in inflammatory leucocytosis).t B. Cells Normal to the Leucopoietic Tissue, but not destined TO ENTER THE BLOOD-STREAM. Lymphoidocy te . Leucoblast. Neutrophile promyelocyte. Eosinophile promyelocyte. Neutrophile (mother) myelocyte. Eosinophile (mother) myelocyte. Neutrophile metamyelocyte. C. Cells Usually Confined to the Leucoblastic Tissue, but ENTIRELY ATYPICAL. Lymphoidocyte with Rieder nucleus. Polynuclear leucoblast (basophile, non -granular, polynuclear). Non-granular myelocytes with oxyphile cell-body. Dwarf myelocytes. Metamyelocytes with basophile cytoplasm. Polynuclear macromyelocytes : cells like the lymphoidocyte, but having a definitely polymorphous nucleus, and containing specific granules. Hybrid cells : with both eosinophile and mast-cell granules :% (a). Mast cells with eosinophile granulation as well. (6). Eosinophile cells with mast granulation as well. (c). True bastards. The Birth of the Neutrophile Leucocyte into the Blood- stream. — Reference has already been made to the suggestions of Blumenthal and Errera, to the effect that the mechanism of the Hberation of these cells into the blood-stream is largely physical in nature. On the other hand, the known migratory power renders the phenomenon less difficult to understand. The actual factors which bring about the migration at this stage, and not earlier in the prenatal life-history, are, however, completely unknown to us. * Seen in myeloid cUoroleuksmia (Hellyj. t These are presumably derived from pro- or myelocyte forms by nuclear differentiation, and not from the micro-promyelocyte forms. X Seen in myeloleuksemic blood-cells. See also under eosinophile cells. Life-Cycle of the Blood-mature Leucocyte 213 III.— THE LIFE-CYCLE OF THE BLOOD-MATURE LEUCOCYTE. The morphological characters of the cell — Arneth's system ; Schilling's modifica- tion — The functions of the cell — Chemical characters : the granules : neutro- philic, iodophihc, sudanophilic, phenolphilic, oxydase, myeloic azur — Theories relating to the nature of these granules : ferments ; extractives — ^The death of the leucocyte — Phenomena in the cytoplasm, and in the nucleus — The comparative cytology of the neutrophile leucocyte. The Morphological Characters of the Neutrophile Leuco- cyte are as follows : — Size. — 10-12 /i. Shape. — Spherical when at rest, polymorphous when in motion. Cell-body. — Strikingly oxyphile in reaction. Relatively abun- dant, but spongioplasm not conspicuous. A centrosome is present. Heidenhain^e believed that the centrosome was formed of the radii of force tending to bring the astrosphere into the centre of the cell. Fis- 55- — ^lyECCOCYTES SHOWING Ahceboeo MOVEMENT (after Brugsch and Schilling). Granules. — The cell-body is loaded with the specific granules, which are chiefly congregated towards the periphery of the cell, and are scanty in the perinuclear zone. They are more clearly demon- strated by triacid than by Giemsa. Azur granules are absent. Nucleus. — The shape of the nucleus is polymorphous. It is 214 Biology of the Blood-cells rich in chromatin, and poor in parachromatin, following the usua rule of condensation with progressive maturation. Nucleolus. — Absent. The characters of the nucleus are not necessarily fixed ; they may even vary from hour to hour. Neumann^' considered that abnormal stimuli might cause a restriction of movement of the leucocyte with resultant retrac- tion to a spherical or lymphocyte form, just as the latter does not exhibit amceboid properties while circulating, but appears to do so under certain other conditions. On the other hand, the functional as well as the nuclear differences between the lymphocyte and the polynuclear, render this idea of changing morphology rather unlikely. Researches by Brugsch and Schilling^* on the nuclear changes in this cell as seen by dark-ground illumination show that the lobation does not alter fundamentally whatever be the change of shape of the cell-body in the course of the amoeboid movements. More precisely, the type of the lobation does not change (Fig. 55) ; segments do not turn into bridges, or vice versa. However attenuated the nucleus may become, it will not show such slender bridges as to simulate the filamentous interlobar connections characteristic of bi-, tri-, quadri-, and multi-partite nuclei. The writers quoted are inclined to believe the contrary to what has been stated above, but their drawings do not entirely bear them out. Fig. 56. — Neutrophiles from a case of Acute Pneumonia (after Brugsch and Schilling). Dia- grammatic drawing to show the varying nuclear form, (i) Neutrophile with rod-shaped thick nucleus (acute pneumonia) ; (2) Neutrophile with bisegmented thick nucleus ; (S) Neutrophile with rod-shaped slender nucleus ; (A) Neutrophile with tri-segmented slender nucleus. The first two are young cells, the last two old. The filamentous change with the polynuclear leucocyte has been regarded by Deetjen^' as evidence of amitosis, though this view is not accepted by Brugsch and Schilling, because they aver that such appearances can be induced at will by over-heating the preparation. In that event, the number of seg- ments in the nucleus does not per se decide the age of the cell ; they only indicate the effect of opportunities of more or less vigorous amoeboid activity. The age of the cell may, however, be deduced by noticing the actual bulk of the nuclear matter. In the accompanying figure (Fig. 56), for instance, the younger cells show thick nuclei, while the older ones have small lobes and long filamentous interconnections, or are more slender than the first -named. The polymorphonuclear leucocytes were subjected to elaborate classifica- tion by Arneth,'" under the idea that a careful study of the segment-nuclear forms might afford data valuable to the clinician. Fig. 57 forms a convenient graphic representation of the scheme. Life-Cycle of the Blood-mature Leucocyte 215 Class I. M •2 per cent Percentage in normal T blood. 5 per cent. 3 II. 2K •27 per cent 2S 23*46 per cent IKIS ii'69 per cent 35 Class III. 3K 2*27 per cent 3S 5*6 per cent 2K1S i6'66 per cent 1K2S l6'4 per cent 41 Class IV. 4K 4S 3*8 per cent '07 per cent 3K1S 6'4 per cent 3SiK i'6 peTi^cent 2K2S 4'73 per cent Class V. 5K 4KrS 3K2S r per cent 0*4 per cent 0*4 per cent 4K2S 3K3S •07 per cent -07 percent Fig. 57. — Graphic Representation of Arneth's System. 216 Biology of the Blood-cells There are several objections to the theory : (i) Brugsch and SchiUing's view that degree of segmentation of nucleus has no relation to age of cell ; (2) Reniform nucleate myelocytes are thrown into the same category as metamyelocytes, and yet one has an amblychromatic nucleus, and the other a trachychromatic nucleus. These differences are not brought out by triacid staining (the method utilized by Arneth) ; (3) A polynuclear leucocyte, according to Neumann, becomes simpler in form when it ceases amoeboid movement ; (4) Heat fixation accounts for the deep nuclear indentations. Weidenreich, using Deetjen's agar method, considered that the poly- morphism of the leucocyte nucleus was a sign of morphological, but not of ^ ^^ -JSt- — »- — • 3 ^1 c ii IS 1 a Neutrophiles 1 Normal 6 I 3 , 4 63 23 6 Typhoid fever 3 — — 30 19 36 15 Severe sepsis 7 — — 1 12 49 25 9 4 Liver abscess 6 I 2 — 27 42 20 8 Ankylostomiasis . . 6-5 2 32 — 4 32 22 8 Leukaemia . . 50 3 6 14 13 20 36 3 5 Lymphatic leukaemia 120 — I . — 2 I 55 41 Aplastic anaemia . . 3 I 2 — — 5 62 23 6 Hodgkin's disease 57 I I — — 7 40 45 8 The figures in thick tj^e indicate how the " picture " is deviated in one direction or the other. Thus, the youngest type of polynuclear leucocyte in normal blood is the rod-nucleate form. In typhoid fever the picture is deviated to the left (great increase in rod-nucleate forms, diminished segmented nucleate forms). In severe sepsis there is marked deviation to the left (black figures in first two columns of neutrophiles, with still higher percentage of rod- nucleates). Similarly with leukaemia. On the other hand, in lymphatic leukaemia the picture is deviated to the right, the chief figures being in the lymphocyte and large mononuclear columns. The aplastic anaemia shows no deviation. Note the high and low values marked in thick type in the other cell-columns, which draw attention to lymphocytosis, lymphopenia, eosinophiUa, large mononucleosis in the different diseases. Some work on this subject carried on by Minor and Ringer furnishes interesting results which, though not giving exactly the same figures as those of Arneth, nevertheless point in a similar direction. A good idea of the real usefulness of this method of study is shown by the chart given {Fig. 60), Life-Cycle of the Blood-mature Leucocyte 219 where the cases are divided into normal, good, medium, bad, and very bad (from the prognostic standpoint). The figure (I) indicates cells with only one nucleus or two lobes joined by an isthmus ; (II) Double nuclei connected by only a thread ; (III) Three segments ; (IV) Four segments ; (V) More than four segments. The increase of Class I cells in the very 40% Fig. 60. — Chakt illustrating Arneth's method. {After Minor and Ringer.) bad cases is shown in a striking way. An example is given in which a patient suffering from tuberculosis seemed to be doing well, but showed a count of 20-45—30-5-0. This count could not be explained until, a few days afterwards, the illness relapsed, spread rapidly, and ended fatally. 220 Biology of the Blood-cells Characters of the Leucocyte as seen with the UUramicroscope. — The cell-body shows three zones : an outer narrow zone in which there are silvery motile granules of large size, a middle zone of large granules where motility is very active, and an inner zone of rapidly -moving or dancing particles.32 Some of these were thought by Pappenheim to be lipoid.ss It is from the middle zone that the pseudopodia arise, and when vacuoles appear in the cell they are found to be situated here. The inner perinuclear zone is clear and devoid of granules. The nucleus itself is opalescent and shows a finely granular structure, the granules being arranged in filamentous fashion. There are some larger non-motile granules within the nucleus. A centrosome can be seen in its vicinity (Schillings^). The Leucocyte as seen by Vital Staining. — Brilliant cresyl-blue or neutral-red does not stain the nucleus unless the cell is dead. Numerous dancing particles of brilliant colour are seen in the cell- substance by this means. The Leucocyte as seen with Ultra-violet Light.— Gravfitz found that the granules come out most distinctly. They are seen to vary much in size, even in the same cell. The variable opacity of the granules shows that they are not all of the same nature. The nucleus is much more transparent than in the case of the lymphocyte — a fact which points to differences in chemical constitution ; further, the bridges between the segments are found to be replaced by broad bands. Mitosis. — Does the circulating leucocyte undergo mitosis ? According to Schafer, mitosis occasionally takes place.^s Pollitzer^^ described the following changes in the nucleus during circulation. Curving of the arms of the nucleus round the centrosome, almost, if not quite, up to ring formation ; clumping of the chromatin to one side till an equatorial band is formed, such as is found in the neutro- phils in cases of infective disease. This again divides into a double row of nuclei, which pass to the opposite poles of the cell. Looked at in this way, the partition of the nucleus into fragments (caryor- rhexis) is really an incomplete mitosis. In support of it is the state- ment that constrictions of the cytoplasm may be observed round these nodal masses, with accumulation of granoplasm around each Life-Cycle of the Blood-mature Leucocyte 221 nuclear fragment. Weidenreich^^ believes that the phenomenon is not proliferative, but, as described previously, degenerative in character. Differential Diagnosis. — It is hardly possible to mistake a polynuclear leucocyte in a blood smear, but imder certain circum- stances there may be temporary doubt about some of the variant forms. The distinction from a metamyelocyte, or from an aberrant parent cell with polymorphous nucleus and no neutrophilic granules may be difficult at times, but will be based on the nuclear characters detailed on preceding pages. The distinction between the neutro- phile and a large mononuclear leucocyte with a polymorphous nucleus is made out by noting the presence of delicate bridges between the nuclear segments in the one with tracbychromatism of the nucleus in the one, as con- trasted with the findings in the other. {Fig. 6i). The tendency to loss of typical characters un- der the influence of degenerative changes may also cause difficulty. _,^ ^ . - Fig. 6i. — The neutropliile leucocyte la) These degenerative changes are and large mononuclear ceU (6) contrasted. referred to below. The Functions of the Neutrophile LeucocYte. — The relation of this cell to phagocytosis and immunity is best dealt with in treatises on that subject. Of interest in connection with the biology of the cell, however, is the problem concerning the purpose of the granules present in its cytoplasm. The influence of surface-tension phenomena upon the power of amceboid movement has been considered by Loeb and Michaelis.^s The superficial saponification of the lipoid envelope by lipoid soluble substances in the blood in such bacterial infections as cause destruction of red cells would form an instance in point. The action of saponin and hydroxylamine on the blood-forming organs s 9 has furnished parallel evidence. Massart and Bordet^o found that the addition of a drop of oil to frog-lymph in a moist chamber would suffice to inhibit the output of pseudopodia. Chemotaxic influences on amoeboid movement have been widely studied, and Metchnikoff has regarded the process of anti- 222 Biology of the Blood-cells bacterial immunity as nothing more than a conversion of negative into positive chemotaxic influence on the leucocytes. The influence of such simple agents as sodium chloride, calcium chloride, alkalies, potassium chloride, adrenalin, calcium« on phago- cytosis is of much interest, but will be passed oVer. Chemical Characters. — The Granules of Polymorphonuclear Leucocytes. — The granules which may be detected in these cells vary in size. They show active Brownian movement, dependent on purely physical circumstances, since changes in the molecular concentration of the medium influences them (Achard and Ramond*^). They are visible with dark-ground illumination as well as by vital staining. The following varieties may be distinguished : — Neutrophilic and variants (basophilic, oxyphilic) lodophilic Sudanophilic Phenolphilic Oxydase Myeloic azur granules (in parental cells). The Neutrophilic Granule and its Variants. — The pro- blems relating to the origin and purpose of these various granules are as compUcated and difficult of solution as are those relating to secretory granules in general. The leucocyte granules are variously interpreted as secretory, as precipitation-effects, as metabolic products, as zymogen, as nodal intersections of the spongioplasmic network, or as degeneration products. I. That they are Precipitation Effects. Pro. — («) Analogy with the deposition of starch grains in a vegetable cell (Ehrlich). (b) The granules increase in number in the presence of pyo- cyanase, which contains ammonium carbonate. ^3 (c) The addition of saline to an emulsion of leucocytes is found to increase the number of granules. These new granules are very minute and are soluble in lo per cent saline, indicating that they are globulin precipitations. (d) Loeb44 found that osmotic influences may cause the disap- peaiance of granules from the cell, hypertonic solutions withdrawing Life-Cycle of the Blood-mature Leucocyte 223 water and rendering the granules indistinct, whereas hypotonic solutions cause swelling and vacuolation of the cell-body. Acid reaction may cause them to disappear. The Brownian movement depends on the texture of the intergranular cytoplasm under varying conditions of tonicity. (e) Dark brown or black granules of varying size are found round and on the nucleus when the triacid stain is used. These are the effect of heat fixation or the artificial effects of the dye (Neusser's perinuclear granules). Con. — The granules stain vitally and give the indophenyl-blue reaction. 2. That they are Nodal Intersections of the Spongioflasmic Net- work (GuUana^e). Pro. — Pollitzer's views^s about granoplasm, as a third consti- tuent of cell substance. This is so dense in mature cells that the true hyaline cytoplasm can only be seen in specimens which have been crushed. It may simulate chromatin structures in the nucleus, in that optical projection causes the granoplasm to appear to be within the nucleus as a nuclear network. This would explain the view expressed by Decastello and Krjukoff*^ that the granules are segments of caryogenic protoplasmic fibrils. Con. — {a) The granules have no relation to spongioplasmic structure (Ehrlich). (i) They disappear during starvation without a disappearance of the other (Kollmann). (c) The fact of active Brownian movement while within the living cell, especially under certain conditions (Miihlmann*'?). 3. That they are of Secretory Character. — They may act the part of an internal secretion. Downey* s points out that certain leucocytes of the fish may have such a function, the cells being looked on as unicellular glands with the power of phagocytosis added. Bound up with this question is that of their specificity. Pro. — {a) The peptic action of the cells. {b) They are absent from the starving cell. (c) Their staining reactions are specific. {d) The reaction with indophenyl blue. (e) Loew and Bokorny*^ showed that the addition of such weak 224 Biology of the Blood-cells bases as very dilute ammonia and ammonium carbonate to a preparation of living spirogyra would cause granules to appear within the cytoplasm. These were called proteosomes, because they were derived from labile protein, and had the property of reducing very dilute alkaline silver solutions (i.e., aldehyde protein). Similarly a + per cent solution of caffeine produced a similar phenomenon on these vegetable cells, the granules dis- appearing again when the filaments were placed in pure water. The granules stained with neutral red were actively Brownian, and soluble in Lugol's solution (cf. glycogen granule). (/) Schneider's study of the relation between complement and bactericidal substances.eo The so-called leukine is of complement character. The whole subject of the relation of leucocytes to complement and amboceptor is paramount evidence in favour of the view in question ; Metchnikoff has strongly advocated that the specific secretion of these leucocytes is complement. Con. — (a) Oxnersi showed that when nemertines are stained vitally by methylene blue and neutral red, the mucus which they secrete is colourless, although the mucin cells contain many vitally- stained granules. This indicates that the granules are not neces- sarily secretory. (b) Eosinophile granules are not specific, therefore neutrophile granules are not necessarily so.* 4. That they are Zymogen. — In favour of this view is the analogy to the granules in the cells of secretory glands. They give a proteolytic reaction. Microchemical reactions show the presence of marked acidity in the vicinity of ingested particles. Drzewina^s found that acidophile leucocytes were very common in the hepato- pancreas of fish, and concluded that the granules were thrombogen. Fry54 suggested that the large granules of fish leucocytes were " kinases " concerned in coagulation. Against the view is the fact that some are lipoid (Ciaccio^s), and that they are genetically related to the plasmosomes. 5. That they are Metabolic Products. Pro. — {a) They are absent from the starving cell. KoUmaun found that the granular cells in the tortoise contain amphophile granules j '.^at first, and acidophile granules later, with associated changes of solubility. ,-• ^ _j_i Life-Cycle of the Blood-mature Leucocyte 225 (b) Some of them are lipoid.se (c) Different kinds of granule can appear in the same cell. {d) NeutrophUe granules can be made to stain acidophile or basophile at wUl (Marinose). (e) They are normally present in the rabbit bone- marrow (L6wit52). (/) The view that they come from the nucleolus (Bogdanoffs''), or from the nucleus (Sabrazes and Muratet^s) in scyllium, is in support of this interpretation. Con. — (a) Their specific staining reaction. (b) Their genetic relation to the plasmosomes (Arnolds^). (c) Their reaction with indophenyl blue. (d) The arguments in favour of their secretory nature. (e) The fact that stimulation of the bone-marrow in rabbits is never associated with a failure to breed true neutrophile granular cells (Schwarzso). (/) The triacid stain shows the presence of green granules around the nucleus (Neusser's perinuclear basophilia), which, in spite of the staining reaction, are not made of nucleo-albumin. (g) They are not affected in number by the uric-acid diathesis. 6. That they are Degeneration Products. — Against this view is all the evidence for their secretory nature, and the fact that they are present in mitosing cells. The Basophilic Granule. — Extremely fine granules can be seen, especially when methylene blue is used alone. Pappenheim con- siders them to be spongioplastic, but Schur and Grawitz seem dis- posed to regard them as precursory granules. The Oxyphilic Granule. — It is well known that some of the very fine (so-called) neutrophile granules stain as brilliant a red as do the coarse eosinophile granules. It must be admitted as possible for a neutrophilic granule to become oxyphilic. The neutrophile myelo- c}rte is the only cell which shows genuine neutrophilic granules. On the other hand, the view that a, /3, y, I, and e granules are successive phases of the same granulation has been done away with by Pappenheim. 61 The Iodophilic Granule. — Normal leucocytes do not stain with iodine. Abnormal ones may show the following three grades 15 226 Biology of the Blood-cells of iodophilia (stainability with iodine) : (a) With rod-like granules ; (6) Diffuse colouring without granules ; (c) Brown-red inclusions. In the last two cases, the iodine reaction is a sign of degeneration (Commessatti62). In the first case the granules may form clumps within the cell-body. Conditions in which the iodine reaction (glycogen) is met with : spreading suppurative processes, general sepsis (if not too virulent), at the acme of appendicitis, pneumonia, pyaemia, diabetes, per- nicious anaemia, leukaemia. In such cases 90 per cent of the poly- nuclears may show the change. Significance. — The presence of glycogen granules in the leuco- cyte may be taken to mean increased functional activity (W. H. Brown63), or it may be a degenerative process (Da Costa^*), since myelocytes do not show it. Pappenheim^s regarded it as a product of the interspongioplastic paraplasm. Abetti^e used it as a sign of inflammation somewhere in the body. Woskressenski^T considered that it means a severe infection. Neukerich'* divides the bodies staining with iodine thus : — 1. True glycogen — stainable with iodine and Best's carmine, soluble in saliva. 2. lodophile substance stainable by Best's method, but not soluble in saliva. 3. Granules in leucoc5rtes and myelocytes which cannot stain with iodine, not soluble in saUva, but stainable by Best's method. 4. lodophile substance only partly stainable with Best. 5. lodophile substance in a diffuse form, not stainable with Best. This author believes that the bodies staining with Best's method are preglycogen, which break up with necrobiotic processes into not readily soluble glycogen-like substances ; with less severe processes, bodies appear which are readily soluble. The Sudanophilic Granule. — Leucocytes containing granules staining with Sudan III were called lipoferous leucocytes by Ciaccio.6 9 The granules vary in size up to i fi. In severe suppurative processes, 90 per cent ol the neutrophiles contain this form of granule, 35 per cent show it in suppurative processes with much anaemia, and 15 to 20 per cent in rheumatism, tubercle, and chronic infections (Quarelli and Bottino). They are met with in Life-Cycle of the Blood-mature Leucocyte 227 puerperal blood.™ They do not vary with digestion (Ciaccio, Tousset et Troisier''^), According to some authorities, the phenomenon is degenerative, and concomitant with the similar change seen in any cell ; accord- ing to others, the granules are the result of absorption by phago- cytosis of fatty matter in the blood-stream (Martelli^^). The Phenolphilic Granule. — The occurrence of phenolphUic substance in neutrophile leucocytes was observed by Loele, as mentioned when discussing metabolic changes in the spleen. It is related to the oxydase granule. The Oxydase Granule. — This form of granule is not peculiar to the neutrophile leucocyte, and will be discussed in connection with the eosinophile cell. Some forms are stainable with cresyl, neutral, or Nile blue. The Winkler-Schultze indophenyl reaction is the usual method of detection. Sapegno considered the number of oxydase granules a criterion of the age of a cell. Jochmann7 8 thought the granules might play some part in inhibiting the coagulation of the serum in an exudate. Other Ferments in Leucocytes. — Leber's finding^s that aseptic pus has the power of digesting proteid matter was an early observa- tion on the subject of leucocyte ferments. Erben^* studied the ferment action of leuksemic leucocytes, and Miiller and Jochmann^^ studied the question very thoroughly. More recently a full review of the subject was given by WienSj^e to whose work reference should be made. The existence of proteolytic ferment in such cells is of interest in connection with the question of the meaning of pus or suppurative processes generally. The digestive action is necessary for the liquefaction of the tissue, although conditions occur in which this result is undesirable, because of consequent rapid absorption of poisonous metabolic products. Antiferments play an important part in rectifying such error. Extractives in Leucocytes. — Both living and shed leucocytes, when extracted with saline, can be shown to contain bodies which possess bactericidal activity, var5dng in amount with different organisms. The bactericidal substance was shown by Meisner^'' to withstand 60" C. The Myeloic Form of Azur Granulation. — This is present 228 Biology of the Blood-cells only in the immature members of the blood-cell series. There has been much discussion regarding the relation between this and the neutrophile granulation of the mature cell. Pappenheim's^e view is that its basis lies in some derivative from the nuclear matter, remaining temporarily there as a granule, but able to unite vdth azur-eosinate through the aid of an amboceptor basic group. The prevailing tint is then that of the polybasic salt of the colour acid (cyanophile component). The subsequent redistribution of the chemical structure of the granule enables it to unite with the dye through the aid of an amboceptor acid group. The chief colouring is then that of the polyacid salt of the colour base (erythrophile component). Granule Amboceptor Component of Azur-eosinatk Azur Neutrophile Basic group Neutrobasic group Neutroacid group Acid group Polybasic salt of colour base Monobasic ,, ,, ,, Monacid ,, „ ,, Polyacid ,, ,, ,, The reversal of affinity towards the different sides of the colour base must mean a loss of identity of the azur granule in the juvenile cell. It is evident, too, that there can be an intermediate stage between relative immaturity (primitive granule) and maturity (specific granule), the intermediate stage passing continuously from neutrobasophilia to complete neutrophilia, while the passage from the primitive granule to the intermediate stage is interrupted. In physical parlance, the curve is interrupted, and is mathematically expressed as a discontinuous function. Such speculations as these are not purely academic. They illustrate the mechanism of metaplasia in the individual cell, and afford an explanation, for instance, of why large lymphocytic leukaemia may be really myeloid. The Death of the LeucocYte. — The phenomena which have been described as occurring within the myelocyte during the process of its decay are also met with in the case of the mature leucocyte, although they are best observed outside the circulation, on the surfaces of mucosae, in the connective tissue spaces, etc. They are Life-Cycle of the Blood-mature Leucocyte 229 most commonly observed in smears of inflammatory exudates. While the changes are tabulated according to their position in the cytoplasm and in the nucleus, it will be borne in mind that the nuclear changes usually precede the cytoplasmic. Changes in the Cytoplasm. — Vacuolation of the cytoplasm ; fragi- bility ; coagulation necrosis ; albuminoid degeneration ; swelling to giant size (especially in inflammatory exudates).* Changes in the granules : fusion to larger masses i^" partial up to com- plete disappearance ; altered staining (metachromatism) of some, prior to their fusion ; basophile change in the granules ; ^^ unequal decolorization. Appearance of new bodies : fat globules ; glycogen granules ; mast granules (perhaps). Changes in the Nucleus. — Swelling, with separation of the chromatin markings ; fragmentation into portions without filamentous interconnections {see Fig. 58).t Alteration of staining reaction (metachromatism). Formation of uninucleate forms by nuclear agglutination.^^ Fragibility of the nucleus demonstrated in the film preparation.'^ When a pol5niuclear cell is engulfed by a macrophage, the changes noticed during the death of this cell are characteristic. They were first studied by Cesaris-Demel^* in inflammatory exudates induced by inoculations of diplococci. The nucleus first acquires a strong blue colour f in place of the normal violet, then the nuclear membrane becomes lost, and the outlines of the nucleus become indistinct, while the chromatin network disappears. The diffusely- staining body breaks up into several fragments, which appear as formless masses, the whole structure being finally lost. Ciaccio86 found that lipoid substances accumulate in the cell- body during the death of a leucocyte ; sudanophile granules become numerous in the course of pneumococcic infection. Such granules are especially noted in the pus cells of fluid exudates, ^s The average duration of the life of a polynuclear leucocyte has not been determined with any pretension to probability, * This leads to the production of a giant leucocyte. It may be the effect o£ osmotic action, or signify an origin from a myelocyte or myeloblast. t The so-called amitosis is regarded by Weidenreich * ' as a degenerative phenomenon. % Nuclein, nucleic acid -f- nuclease = purin (Ciaccio, quoted by Zoja, F. H. a. l. V- 239)- 230 Biology of the Blood-cells though some authorities consider that it never lives more than a few days.* The Comparative Cytology of the Neutrophile Leucocyte. — True neutro- phile leucocytes are not found far back in the vertebrate scale, and it is doubtful whether the phagocytic cells of the invertebrates should be included among them merely because their functional properties are similar. Hardy's explosive cells*' of Crustacea are hardly exact analogies. They are concerned in the process of clotting in these animals. In the tunicates (Ciona intestinalis] , the white cells are mononuclear, of short round form, with scanty cytoplasm, which is very rich in fine granules.'^ In the scorpion, Kollmann*" found : {a) Large round cells crowded with granules of spherical shape, and specially densely arranged at the periphery ; (6) Smaller oval cells fuU of rod-like granules. The granules stain violet with triacid ; they are amphophile, with a marked tendency towards baso- philia. The fine granules are acidophile. Amphophile granules were only found in one species of tegenaria. In the king-crab, the white cells are similar to those of the scorpion both in form and in granulation. (The serum contains haemocyanin.) Bruntz*" found that the amoebocytes of arthrostracea multiply by amitosis during circulation. The leucocytes of fishes are of two kinds — spindle-shaped and round. Both are covered with small fine granules which stain bright red with Giemsa. The nucleus is elongated in the spindle-shaped forms ; in the round forms it is sometimes round, and sometimes horseshoe-shaped. These round forms are divisible into two groups according to their size. In each case, bright red granules are present, those in the larger cells being angular and less numerous ; in the smaller cells they are smaller and thickly distributed through the cell (Fry'^). The granules of these spindle cells are directly concerned in coagulation. The observations of Sabrazes and Muratet'^ on the blood of the torpedo, have shown that acidophile cells stand in place of neutrophile leucocjrtes of other animals. They occur in two forms : (a) Small cells with ovoid or lanceolate granules ; (6) Larger cells with strongly acidophile granules. In each case the nucleus is rounded. Amoeboid movements are active. The number of white cells is about i8,ooo per c.mm. The blood of the cartilaginous fishes is rich in granular leucocytes, but not that of teleostean fish. The granules in the leucocjrtes of the ganoid fish polyodon were especially well studied by Downey." This author found that there are at least three types of secretory leucocyte, which are not interchangeable : (a) The most numerous forms are nearly round, with large round granules of equal size, fiUing up the cell to such an extent as to crowd the nucleus to one side. The nucleus is reniform, and contains a moderate amount of chromatin. The granules in the cell are amphophile. They * Horbaczewski attempted to deduce it from a ratio between excreted urea and purin bases, as evidence of leucocytolysis, but there is the obvious fallacy that nucleic acid comes from other places as well. Life-Cycle of the Blood-mature Leucocyte 231 develop in vacuoles within the cell-body, and as the granules form, the nucleus diminishes in size. Later on, the granules come to vary in size, and ultimately dissolve away, leaving vacuoles once more, (fc) A cell with small granules which are not so closely packed together as the preceding, but occur all round the nucleus, leaving it central in position. The nucleus does not change in size with the appearance of the granules, but undergoes certain degenerative changes (loss of network, breaking up of the chromatin ; ultimate pycnosis ; final dissolution), (c) A cell with granules which stain brilliantly with safranin. They vary considerably in shape, size, and distribution ; are large, round, or spindle-shaped. When these cells degenerate, they show a polymorphous nucleus and homogeneous colora- tion of the cytoplasm. The whole cell shrinks, and may finally undergo vacuolation. Interesting observations on the formative tissue of the mudfish pro- topterus were made by Stephan."* The lymphoid tissue occurs in the sub- stance of the kidney and round the digestive tube. It is made up of poly- hedral cells, some of which are crowded with granules, staining with eosin, orange, safranin, and fuchsin. Parker thought they were alimentary reser\'e for the period of torpor, but others are indisposed to consider them as such. At the time of full activity, the lymphoid tissue is full of these acidophile cells, but they disappear during the torpid period, and are almost absent in the awakening animal. The first granules appear in the neighbourhood of the nucleus where the cytoplasm is more dense. The granules are at first extremely small, and then enlarge. When the cell is full, the granules lose their affinity for staining, the nucleus takes some share in the liberation of the granules, which appear to arise by pulverization of the fragmenting nucleus. In the amphibia, the granular cells are chiefly mast-cell in type, but uninucleate eosinophiles of characteristic form are prominent. The acido- phile leucocytes of the tortoise arise by the production of granules' in large mononuclear leucocytes, not only in the bone-marrow but also in the loose connective tissue. There are no true neutrophile leucocytes in the reptiles ; eosinophiles are the characteristic granular cell. In triton, the cytoplasm of the neutrophile leucocyte is feebly oxyphile, and contains a scanty basophile network without granules. An amphophile effect is thus produced. The nucleus is deeply coiled, and forms nodes connected by filamentous connections. These are sometimes so indistinct as to give rise to a multinucleate appearance (Griineberg)'^ The leucocyte of siredon has a rose-coloured cell-body, with a scarcely visible basophile network. The nucleus has an S or U -shape. In the frog, the cell-body is amphophile, and shows no granules. The nucleus is markedly polymorphous. In gongylus, the cells rather resemble the myelocyte form of human hasmatology. Metchnikoff's observations on the functions of cold-blooded leucocytes show that the granular leucocytes are able to take up such organisms as cholera, streptococcus, B. tetani, B. coli, B. typhi, B. pyocyaneus, as long as they are not too virulent. In the pigeon they take up avian tubercle bacilli, but are destroyed in the process. They are negatively chemotactic 232 Biology of the Blood-cells to tetanotoxin. In the frog and other reptiles the part of the human poly- nuclear leucocyte is played solely by the macrophage. From these considerations it will become evident that there is no such thing as a true specific neutrophilic-granular leucocyte in the cold-blooded vertebrates. In the birds, the leucoC5rtes include mast-cells, eosinophile cells with rod-like granules (the most numerous), and cells of a similar size to the preceding, but with a bifid nucleus, whose chromatin structure is radial and myeloc5rtoid. The cell-body is feebly oxyphile and full of minute oxyphile granulations. Such cells are very scanty. Kasarinoff," Niegolewski, and others have found these varieties in the fowl, pigeon, and Senegal finch. A few myelocytes are normal to goose blood.'' Among the mammals, the leucoc5rtes of the ape, pig, goat, cow, dog, and mouse' ^ have neutrophile granules, while those of the rabbit show amphophile granules, and those of the guinea-pig acidophile granules. The granules of the horse leucocyte are extremely fine." A few neutrophile myelocytes are normal for this animal. The leucocytes of the goat are small, and the granules stain violet with triacid stain. Furno's observations on the granules in the leucocytes of the domestic animals have shown that in man, the horse, and the dog, the neutrophile granules appear violet with triacid, while the colour is red in the case of the sheep, goat, cow, and pig. Neutrophile granules are not found in the white mouse, rabbit, guinea-pig, cat, or rat — these animals showing only oxyphile granules in their polynuclear cells."" Cytoplasias of the Leucopoietic Tissues 233 IV.— THE CYTOPLASIAS OF THE LEUCOPOIETIC TISSUES. Leucocytosis : principles in white-cell counting ; causes of leucocytosis ; the phases of leucocytosis — Leucopenia — The hyperplastic and metaplastic processes of leucopoietic tissues : contrast between leukasmia and leucocytosis ; auxetic processes. It is of interest to reflect that we never make a differential blood- count without at the same time involuntarily obtaining data for a study of cytoplastic processes in the patient's blood-formative tissues. The better we find ourselves able to make deductions about these tissues by the method of clinical examination in question, the more stimulated do we find ourselves towards pursuing the investigation of the correlations between histological changes and haemocytological formulae. Common as are the evidences of damage to red cells, or even of the erythropoietic properties of the bone-marrow, the most familiar changes observed in blood-counting are doubtless those classed as examples of leucocytosis. I. Leucocytosis. — Strictly speaking, the word leucocytosis should mean the occurrence of an increase in the white cells of the blood as a whole, but common usage limits it to express an increase in the polynuclear leucocytes alone. However interpreted, a case of leucocytosis requires investigation along the following lines : * A microscopic study of the blood-film informs us (a) Whether there is any increase of any one cell-form at all ; (6) Which of the cell-forms exhibit the increase ; (c) Whether the cells present are all mature, or are admixed with immature, juvenile, or prematurely liberated cells. Secondly, an examination of the blood by means of the counting pipettes shows us (d) How much increase of the white cells there is. These various data enable us to speculate as to the character of the agent which is setting up the change called leucocytosis. It is well known, that while the total cell-count may reveal no change in the white cells, the differential count may show the existence of what is called relative leucocytosis, but it is far from * Ably laid down by Pappenheim"" 234 Biology of the Blood-cells customary for clinicians to extend the study of the blood to this point.* Still less is it customary to report upon the white cells of the blood in a manner which shall show the ratio between mature and immature forms circulating in the peripheral blood at the given time of examination. The changes to be looked for may be tabulated as follows : — Quantitative Changes : — 1. Total number of white cells increased — Absolute leuco- cytosis. 2. One type of cell alone increased — Relative leucocytosis. 3. Total number of white cells diminished — Absolute leuco- penia. Qualitative Changes : — 4. Normal types of cell alone present. 5. Ontogenetic forms (a). Present. (6). Preponderant. 6. Phylogenetic forms present (ancestral cells, up to leucoblast). Combining these according to the most practical requirements, we have the following, arranged in symbolic form : — Class A. 2 + 5a + I Class D. 2 + 4 alone „ B. 2 + 5& alone „ E. 2 + 5 + 3 „ C. 2 + 4 + 1 „ F. 3 + $b (possibly i also). In each of these cases we are dealing with an effect produced by some noxious agent which acts either on the blood or upon the tissues forming the cells. The character of this agent is either inflammatory, infective, or non-infective. Two or more may be acting at one and the same time. The mode of action may be in the direction of stimulating or paralyzing the bone-marrow, and finally of producing or inhibiting regenerative processes. In that the phenomenon of leucocytosis is to be interpreted as evidence of a reaction towards an organism or substance, for the purpose of * Thus, in a case of lymphocytosis of 35 per cent (quoted by Pappenheim), with eosino- philes 12 per cent, the lymphocytes are increased 10 per cent, and the eosinophiles 8 per cent ; and yet the percentage increase of the lymphocytes is 40, while that of the eosinophiles reaches zoo 1 Gytoplasias of the Leucopoietic Tissues 235 protecting the body as a whole, we may speak of a reactive leuco- cytosis — a process demonstrating to us that there is a need for the prevalence of a particular cell, associated as a rule with effective powers of mobilizing the supplies. As soon as there is a failure to carry out the latter, leucopenia results, or immature cells appear in the blood. Leucocytosis, then, is a symptom, the result of various circum- stances conveniently codified by the phrase " infective process." Just as a number of conditions must be fulfilled before infection can take place at all, so the reaction of the bone-marrow depends on the nature and mode of action of the exciting agents,* on the indi- vidual peculiarities of the organism at work, on time-intervals (stage of disease), and the character of the viscus or tissue which first bore the brunt of the attack. Leucocytosis is a " function " of all these factors. A noxious agent may be chemotaxic purely for the particular leucocyte, and draw out a certain number of the reserve cells already present in the bone. Another noxious agent may do more than this : it may stimulate the cell to a certain degree of activity, so that new ones are being made in larger numbers. The degree of activity may be just sufficient to satisfy the demands of the moment, may be in excess of demands, or may result in the discharge of immature forms into the blood-stream. Under ordinary circumstances the youngest cell to appear in the blood is the metamyelocyte, but in some cases myelocytes appear to the extent of i or 2 per cent. Finally, cases may occur in which paralysis of white-cell formation sets in, the demand being beyond the powers of the tissue — or inhibition of cell-multiplication has ensued — so that leucopenia results. In other words, diminution of total numbers of white cells, or of neutrophUe leucocytes, may be regarded as an extreme stage of leucocytosis. As has been stated, all manner of noxae may set up leucocytosis, even substances arising in the course of physiological metabolism being able to excite it {e.g., digestion leucocytosis), so that every noxa must not be regarded as necessarily pathological. Such bodies as nuclein, nucleic acid, adrenalin, lactic acid — formed during * Bennecke, F. H. ix. 2, p. 154. 236 Biology of the Blood-cells normal metabolism— will account for the ever-varying numbers of these cells in the same individual's blood. It will be evident that the difference between physiology and pathology here lies in the curious circumstance that in the former, supply exactly meets demand (which is only of temporary character), while in the latter the demand is in excess of the normal, and may or may not be temporary. Study of the blood of infants by Wertistedt^i has shown a remarkably rapid variation of the leucocyte content. Thus, the waking infant readily shows leucocytosis, while during sleep there is a marked fall in the white-cell content of the blood. Active muscular movements appear to account for the increase occurring during waking hours, a point of interest in reference to the subject of myogenic leucocytosis already referred to [Chapter III.). Drugs Causing Neutrophile Leucocytosis. — Arranged alphabetically, the following may be mentioned : Anaesthetics (ether, rarely chloroform) ; blood-poisons, such as met-haemoglobin formers (potassium chlorate, pyrogallol, phenylhydrazin, pyrodin, salicylates, antipyrin, antifebrin, phenacetin) ; camphor ; cinnamate of soda, cinnamic acid ; collargol ; ^"^ digitalis, digitoxin ; * ethereal oils (Meyer) ; fats,"* gelatin ;i- irritants such as turpentine, croton oil, copper sulphate ; nuclein, nucleinic acid -.^"^l organ extracts ; ozonized turpentine intravenously in animals ; "' antitoxic sera ; tinct. amara and quinine (Hirt) ; ;f-rays,act in ten minutes (Krause)."' Other Agents. — Pregnancy, haemorrhage, cancer, septic and inflammatory conditions ; such diseases as rickets, gout, acute yellow atrophy, cirrhosis of the liver. The above list does not exhaust the possible causes of the condition. It will be evident that the ordinary physiological phenomenon of leucocytosis will itself react upon the formative organs, and excite a compensatory proliferative activity, § whose result is an automatic replacement of ceUs into the blood. Should the products of white-cell destruction become abnormal, they would excite an abnormal reaction and tend to bring about the entry of abnormal cells into the blood. Further, it is evident that * Acts in seven to eight hours, and increases steadily after, by actual stimulation (Mirauoi»3) t 40 c.c. of 10 per cent solution, subcutaneously, causes a leucocytosis up to 40,000. J But Lowit states that this destroys white cells, and that it is the break-down products that stimulate hyperleucocytosis. ^ <" § Zoja*^' found that leucolytic substances have a definite specific action on the bone- marrow. Gytoplasias of the Leucopoietic Tissues 237 many circumstances might work together to overturn the equih- brium between leucocytolysis and leucopoiesis. An inabihty or a defective action of the leucocytophages in certain regions may have far-reaching effects. According to Zoja.ns the balance of the processes has something to do with production of leukaemia on the one hand, and pseudoleuksemia on the other. However, the rarity with which such loss of equilibrium is met with, itself speaks against such a view being of fundamental importance, and necessitates still deeper researches into the mechanism of metabolism in the leuco- poietic system. Turning back to consider the possible variations in the white- cell formula in relation to the clinical deductions desired, we find that increase in the polynuclear leucocytes in the blood may take on one of the following forms : — Polynuclear neutrophilia plus (a) absolute hyperleucocytosis : * Class C,t or hyperorthocytosis. Polynuclear neutrophilia plus (b) only relative leucocytosis. Class D, or normo-orthocytosis. Neutrophilia with appearance of metamyelocytes and occasional myelocytes : (a). With absolute hyperleucocytosis Class A, hyperneocytosis (b). Without absolute hyperleucocytosis Class B, normoneocytosis. (c). With absolute leucopenia Class E, hyponeocytosis. Leucocytosis occurs in two degrees : the first degree is usually called absolute leucocytosis, and the second relative. Each is conveniently subdivided into two phases : the first, that in which only mature or blood-normal cells are present, while the second phase is indicated by the presence of immature cells as well. If these are only scanty, we deal with a second-phase first-degree leucocytosis ; if they are prevalent, we deal with a second- * Hyperleucocytosis means a " good reaction," and does not run parallel with severity of intention, t See List on p. 234. 238 Biology of the Blood-cells phase second-degree leucocytosis. If the phenomenon belongs to the first phase, the blood-forming organs are " sufficient," while the second-phase second-degree implies " marrow incom- petence," or commencing exhaustion of the marrow. The degree of the latter is estimated by noting whether there is or is not leuco- penia supervening. The first phase includes : — Cases showing the formula of 2 {see Table on p. 234) without 5. Cases showing i and 2 without 5 (implies a simple leucocytotic irritant). Cases showing 2-1-3. Here the appearance of 5 might be expected to follow very shortly. The second phase includes : — Cases showing a formula with 2 + 5a and no total cell-increase. Cases with 2 + 5a + 1 (reserves being used up). Cases with 2 + 5b + 1 Cases with 2 + 5a + ^ (toxic action on factories, and a sub finem vitcB stage, if 56 appears). Cases with 2-1-56 (or 6) -|- 3 (complete exhaustion). The regenerative phase of functional leucocytosis is expressed by Class B, irritative leucocytosis by class A, a vigorous first stage of leucocytosis by Class C, a commencing or fading reaction by Class D, over-irritation by Class E, and exhaustion by Class F. This mode of presentation gives the necessary changes that may be found in practice, without the redundance of verbiage which would be inevitable were a description of the varieties attempted. It is evident that there is extensive scope for permutations and combinations, but the essential points to notice in white-cell- counting (in non-leukcemic conditions) are the existence or not of neutrophilia, lymphophUia, eosinophilia, monocytosis, and whether juvenile forms are present at all. In the latter event we ask ourselves. Do they go back as far as, or further than, the leucoblast stage ? The existence of juvenile forms is conveniently expressed as a " deviation to the left." 2. Leucopenia. — The opposite condition to leucocytosis is a diminution of the numbers of the white cells of the blood. This may involve all the cells of the white-cell-formula, or it may involve Gytoplasias of the Leucopoietic Tissues 239 only one group. We should then speak of a neutropenia, a lympho- penia, an eosinopenia, a monopenia, etc. In a sense, this dis- appearance of large numbers of a given leucocyte from the stream may be expressed as the extreme stage of leucocytosis. It may also be the result of dissolution of the white cells — so-called leuco- cytolysis — in excess of the normal. Manuchinno found that the injection of peptone, diplococcotoxin, staphylotoxin, or typhoid toxin would produce this effect, and that the heated toxins failed to do so. Such bodies would be called leucocytolysins. The following drugs will cause leucopenia : Large doses of quinine, atropine, benzol dissolved in olive oil (Sellings), thorium X (Falte, Kriser, Zehner^^)^ horse serum. Trypsin produces this effect within three or four hours after injection (Magi^is). Other causes are : Malnutrition, pernicious anaemia, traumatic conditions (shock), protozoan infections (malaria, kala-azar, trypanosomiasis) ; fevers, such as typhoid, measles, Malta, influenza, tuberculosis ; severe toxaemias of any kind. The pathology of leucopenia may be one of the following : Over-irritation by chemotaxic agencies ; exhaustion of the regenerative power of the marrow ; direct paralytic action on the mobilizing powers of the marrow ; direct paralysis of cell- formation (typhoid). 3. The Hyperplastic and Metaplastic Processes of Leucopoietic Tissues. — So -far we have only considered the effects of irritants upon the marrow, acting either at a distance, or becoming concentrated in the tissue itself. We have not referred to the outpouring of leucocytes into the site of invasion of the body by an infective agent, where the chemotaxic force collects all the circula- ting white cells to the spot, and only secondarily acts on the marrow by placing it in a position that demands increased activity on its own part. This is a local leucocytosis. It is easy to imagine that the effect of such a lesion would produce secondary substances that might in their turn set up a blood-leucocytosis, and finally proli- ferative processes in the formative organs. In Leukaemia we have to deal with a different process altogether. In leucocytosis the agent at work lies in the blood-stream or, as 240 Biology of the Blood-cells just indicated, at a distance from the bone-marrow, whereas in leukaemia the agent is situated in the tissue itself. Leucocytosis will cease as soon as the stimulus is removed, but the leukaemic process knows no ending, cannot at the present day be certainly or permanently arrested, and certainly exhibits no spontaneous tendencies towards subsidence, any more than does a sarcoma. We deal here with a hyperplastic or a metahyperplastic process that can never undergo retrogression in the ordinary course of events. The cells liberated into the blood present a moderate degree of mobility and phagocytic power, and retain the power of mitosis, which is not seen in leucocytosis. This is perhaps the really fundamental feature of the disease called leukaemia,* about which so much has been written and so much theorized. A table of contrasts will bring out the important features of the two processes and render detailed discussion unnecessary : — Leukemia Leucocytosis Cause unknown Easily discerned The tissue change is plastic Is functional The process is unhmited Depends strictly on the persistence of a metaplastic reaction or regener- ative stimulus Cell-increase is constant Proliferation dechnes as soon as immature forms appear . The stimulus to h5^erplasia is in In the blood-stream the tissue Ancestral cells are characteristic Do not occur, only ontogenetically immature forms The increased formation of these Immature cells appear only as a cells is the primary change secondary process The prohferation is purposeless Is purposive, and of advantage to the body The cell-division is homoplastic Is heteroplastic, i.e., differentiated cell-types are produced There may be no more cells in the The total count may be normal, but blood than usual (aleuksemia) there is always " osis " The cells enter the blood by pressio The cell-increase is due to tractio a a tergo. fronte. ' See also Chapter I, Section III, and Chapter VII, Section III. Gytoplasias of the Leucopoietic Tissues 241 There is a certain analogy between the leuksemic prohferation and the formation of merozoites in a sarcomatous tumour without discernible immigration of the cells into the blood-stream. On the other hand, to speak of leukaemia as a form of sarcoma is to confuse the significance of sarcoma itself. There is no analogy between a spindle-celled sarcoma of a bone, and a leuksemic bone, and since the published accounts of round-ceUed sarcomas do not include studies along modern histological lines, they furnish no satisfactory evidence in the direction of the comparison so frequently instituted. (See also p. 42.) It is more satisfactory to regard the two diseases as having causative agencies that possess certain features in common. The liberation or not of the homoplastically proliferated ceUs into the blood-stream depends on the position of the cells with respect to the vascular walls in the marrow, and it is far from certain that sarcomatous cells do not circulate in the blood in large numbers in cases of so-called " round-celled sarcoma " or of lymphosarcoma. Observations by the writer in this direction have suggested that more care and more detail in differential counting would lead to the certain clinical diagnosis of at any rate some cases. Auxetic Processes. — Certain interesting researches by H. C. Rossi 14 deserve mention in connection with the cytoplasias of leucopoietic tissue. This observer, working by a special technique, which is equivalent to the much-talked of "in vitro " growth of ceUs, finds that certain substances can influence the mobility of leucocytes, while others excite their proliferation. Such substances were named " auxetic." Common to all these bodies is the amidine grouping : N — C = N. Leucocytes exposed to reagents containing this group would undergo division ; ulcerated areas exposed to such reagents would heal more rapidly than before. " Proud flesh " would be the result of the amidine bodies liberated in the course of decomposition of the exuded matter. Certain of the auxetic substances (amines and aminoacids) were found to require the presence of certain alkaloids (e.g., atropine) before they were activated. Such observations will stimulate further research in the direction of correlating changes in blood-cell formulae with changes in composition of the blood or tissues. Just as it should 16 242 Biology of the Blood-cells be ultimately possible to subdivide micro-organisms according to the atom-groups which their toxins contain, rather than according to their cultural characters, so we should be able to detect the character of the toxin by observing the type of leucocytic or red-cell formula exhibited by the patient's blood or tissues. In other words, the clinical examination of the blood would aim at the detection of certain atom-groups at work in the course of the various infections. This conception finds greater prospect of corroboration by studies of cytoplastic phenomena in the tissues, as will be shown in Chapter VII. ; but the diagnosis of the fundamental character of morbid conditions in the haemopoietic tissues may be aimed at, even if knowledge is never to be actually reached at in full. Further- more, the study of toxic substances able to inhibit or accelerate cell-differentiation, or to turn the developmental sequence along unnatural, lines cannot fail to throw desirable light upon the obscurities of cytometaplastic and allied processes. 243 CHAPTER VI. ON CERTAIN PHLOGOCYTES. Section I. — ^Aberrant Abortive Hemopoiesis : The small round- celled infiltration of tissues — The meaning of the term " phlogocyte." Section II. — ^The Eosinophile Cell : Varieties — ^Morphology — The granules, and their properties — Source — Functions — ^Eosinophilia and eosinopenia of the blood and tissues — Source of the cell — Compara- tive cytology. Section III. — The Mast Cell : Varieties — Morphology of the mast cell of the blood ; of the tissue — Occurrence — ^Function — Chemistry of the granules — Views as to nature — Source — Comparative cytology. Section IV. — The Plasma Cell : Varieties — Morphology of the plasma cell of the blood — Occurrence in the blood — ^Table of blood- plasma cells — Occurrence in the tissue — The lymphoblastic plasma cell — The granules — Ancestry — ^Theories — Effect of plastic irritation of the adventitial cells—Fate of the plasma cell — Functions — Comparative cytology. Section V. — ^The Clasmatocyte and other purely connective-tissue cells — ^The giant cell. Section VI. — ^The Cytoplastic Inter-relations between the VARIOUS Phlogocytes. 244 Biology of the Blood-cells I.— ABERRANT ABORTIVE HEMOPOIESIS. The small round-celled infiltration of tissues — The meaning of the term " phlogocyte." WHEN discussing the lymphocyte, it was pointed out that morphologically similar cells occur in many tissues, both normal and pathological, under the guise of " small round-celled infiltration." That is to say, there is evidence for the belief that some of the circulating lymphocytes may make their way into the tissue spaces. Fig. 62 shows lymphocytes scattered in the vicinity of a small duct in the breast, without any definite suggestion that their presence is in any way abnormal — since the capillaries show no changes, and there is no undue deposition of fibrous tissue. The presence of these cells must nevertheless signify the existence of an attracting agent, and from what has been said about the function of lymphocytes, we should assume that some abnormal kinds, or an excess of normal fatty acids, diffusing through the walls of the duct, are being dealt with by the cell- accumulations, in some mysterious way. A similar explanation affords a satisfactory clue to the meaning of the var5dng forms of infiltration met with in the interglandular tissue of the small intestinal tract. A slightly different form of round-celled accumulation is shown in Fig. 63, taken from the meduUary region of the adrenal, where such ceU-aggregations are not infrequently found. The cells are not all of the same type, but vary considerably in size, while some have pale and others dark nuclei. There is no obvious relation between these cells and a blood-vascular channel, so that the meaning of the process must be slightly different from that quoted for the breast. On the other hand, the adrenal cortex is rich in lipoids, and it is easily understood that the lymphoc3rtoid cells may play some part in relation to them. There is here no evidence of chronic inflammation, so that the cell-aggregation would not be lymphocytes saittcred in the vicinity of a small duct in the breast " (p. 244). fjo^ ^2. — The trifid duct is noticed in the centre, while a few small round cells occur here and Iheie tissue aroimd. (Oc. 2, Zeiss Obj. A) in the loose tissue around. " The cells are not all of the same type, but vary considerably in size, while some have pale and others dark nuclei" (p. 244). f(g_ (^^. — Adrenal Medulla, showing Small-round-celled Infiltration. The large, pale, ill-defined cells at the upper and lower portions of the photograph are the adrenal cortical cells. The small round cells filling up the remainder of the field are those referred to in the above quotation from the text. (Oc. 2, Zeiss Oil-immersion.) Fa^^ />. 3/^\ the scattered round cells are separated by a fluid containing granular matter {coagulable protcidl, and are admixed with . . . elongated spindle-shaped cells" (p. 245). /Tj^. 64.— View in a zone of CuRONac Inflammatory Cell Infiltration. Most of the cells in this figure arc small round histiogenic Ivmphoctyes. ~ '^ (Oc. 4, Zeiss Ap<.chrom. 4 mm.). "... a large polygonal cell is noticed, which has a granular cytoplasm and a relatively large rounded nucleus" (p. 245). Fig. 65. — Another view'in the same zone as the preceding. This photograph shows the uniformity of morpho!og\- of the lymphocytes, the presence of an endothelioid cell, a fibroblast, and the -existence of astral processes from l^'mphocyte to h-mphocyte, as if they organize by joining hands. Above the large cell referred to in the text quotation is a dividing macroplasma cell. (These tu.'o photographs arc fro:n a spcciiiten oj chronic syphilitic orchitis.) (Oc. 2, Zeiss Oil-immersion). Aberrant Abortive Haemopoiesis 245 correctly placed in the same category as the small round-celled infiltration of chronic inflammation. Further, a comparison of such cells with those seen in a lymphoid follicle reveals the fact that in each case we have large, medium, and small lymphoid-cell forms, each being a successive generation. It may be assumed, then, that there is some resemblance between the two cell aggrega- tions, and we might speak of the adrenal collection as a Ribbert lymphoma, which, it was pointed out, is an accessory factory of lymphoc5rtes. When we compare these forms of infiltration with a definite inflammatory mass (Fig. 64), we find a certain degree of resemblance between the ceU-constituents in each case, but here the scattered round cells are separated by a fluid containing granular matter (coagulable proteid), and are admixed with a variable number of elongated spindle-shaped cells (young fibroblasts), and not in- frequently the lymphoid cells may be seen to throw out slender processes which interlace with those of adjoining cells. In this way a variably dense meshwork is produced. A large polygonal cell is also noticed {Fig. 65 ) which has a granular cytoplasm and a relatively large rounded nucleus. Such a cell bears a resemblance to the primordial cell of the tissues, and its presence must bear some relation to the other cells already referred to. The multitudinous types of cell which are described in inflammatory tissues, or tissues recovering from some injury (repair) form a striking feature of the process, and it is well known that every case of small round-celled accumulation does not go on to the formation of a dense spindle- ceUed tissue. For some unknown reason, some of these cases remain lymphoid, others become, and remain, plasmoid, others eosinoid, and a few become fibroid. Under the influence of exceptional stimuli (e.g., a;-rays) fibroblasts may alter their characters, undergo true anaplasia (in chemical parlance, we have a reversible reaction), and deviate along any other line of develop- ment. This interpretation cannot be proved beyond cavil, because it is impossible actually to trace one individual cell-form into any other. The fibroblast, for instance, may really have undergone necrosis and solution, while new lymphocytes enter the scene of action. On the other hand, the plasmoid change is traceable 246 Biology of the Blood-cells through various stages from a lymphocytic outpouring to an extent sufficient to make it very suggestive that fibroid and eosinoid changes may actually take place also. It must be pointed out, further, that the only difference between a tissue made of fibroblasts and true fibrous tissue lies in the amount of dead inert material (Gewebsschlacken) containing something akin to chondroitin- sulphuric acid, which has been sweated out or deposited around the formative cells that have lost the power of movement ; they lie inert among their excreta until in process of time they suffer asphyxia, or starvation, owing to the inability of the necessary food materials to penetrate or osmose through this new coUoidal material. In those cases where the cells do not succumb, the removal of the excreted matter by ferment action would once more liberate the ceUs, and render them amenable to some auxetic or kinetic stimulus, convert them into free-floating cells, and rejuvenate them suffici- ently to despatch them once more along the original cycle of changes familiar to them at an earlier period of their life-history, when the original stimulus or irritant had set the so-caUed inflammatory process in motion. From these considerations it is seen that one can trace a definite series of changes in the cells scattered through the tissue spaces which is quite analogous to that already described in the case of the well-known blood-cells. If the parent of a blood-cell is at one time an adventitial cell, there is no reason for excluding the tissue-cells of the types mentioned from origin in a similar parent. The invention of the term " phlogocyte " by Tiirk, emphasizes the family resemblance between the two main groups of migratory cells, and a description of the biology of the blood-cells would be incom- plete without a consideration of the changes which may take place in some of them after they have left the circulating blood. The association of plasma ceUs, eosinophile cells, and mast cells with the ordinary pulpar ceU of the lymph-node and spleen is sufficient to show that there must be some very close relation between the hsemopoietic and the phlogocyte series (phlogopoiesis), which is probably correctly expressed by saying that certain of the lymphoid- ocytar cells may at one time give rise to circulating cells and at another to local tissue inhabitants. The latter may occasionally "... the difficulty of certainly distinguishing daughter-plasma-cells from a lymphocyte " (p. 273). Fis- 66. — Chronic Inflammatory Cell Infiltration in a case of Gonorrhce\l Salpingitis (a, a), danghter plasma cells; (b), lymphocyte, with nucleolus; {c), lymphoblastic cell; (d), large or mother plasma cell; (c, c), adventitial cell; (/, /), polynuclear leucocytes; (n), eosinophile cell. (Oc. 12, Zeiss Oil-immersion). Fif;. 67. — Portion of a Capillary Wall in an Inflammatory Area in a case of Cilronic Interstitial .Appendicitis, {a), endothelial cell lining (/;), the vascular channel; [b, b), adventitial connecti\-e tissue cells ; (f, c), lymphocytes ; [d], mesench\-mal connective tissue cell ; (c), wandering cell ; [/), plasma cell ; (^'1, eosinophile cell. ((!)c. i^, Zci-^s Oil-immersion. Camcia Lucida Drawing) Face /. _^v7J Aberrant Abortive Haemopoiesis 247 ooze into the blood-stream and appear there as eosinophile leuco- cytes, irritation cells, and mast leucoc3rtes.* In tracing out this analogy between two broad cytoplastic processes, we need to draw a sharp distinction between the acute suppurative processes and non-suppurative conditions. The former are associated with an outpouring of fibrin, and show very few mononuclear cells. With the subsidence of the acute change, however, factors arise which allow of a phlogoblastic development in some cases. Lymphoblastic cells then arise, such as are seen typically in the subacute or chronic gonorrhceal cases of salpingitis (Fig. 66). These lymphoblasts are as truly parental here as in the bone-marrow or lymphatic tissues, but the sequence of development is patently different. We have before us an aberrant hcemopoiesis, shown by the tendency to produce plasma cells, eosinophiles, and no fibroblasts ; at other times, fibroblasts are also produced. The main significance of these cell-forms lies in the fact that future research should teU us exactly what atom-groups are responsible for their appearance in the tissue. The perivascular cellular tissue would then be described, after Pappenheim,! as a slumbering blood-cell-forming tissue (Fig 67), and the fundamental principle common to hcemopoiesis and inflam- matory cell formation would be emphasized. The scheme : — lymphoidocyte -^ eosinophile myelocyte daughter eosinophile myeloc3rte -» eosinophile leucocyte finds its analogue in lymphoidocyte daughter lymphoidocyte -»■ eosinophile myelocyte ->• eosinophile Ismall round cell of inflammatory tissue) leucocyte of (histiogenic lymphocyte) tissue space (tissue lymphocyte) The daughter lymphoidocyte is like a tissue-lymphocyte ; further than this it is not possible to go— we cannot say exactly what may have been the source of any given individual lymphoid * Naegell, Marchand, and Pappenheim believe in the local origin of inflammatory cells, while Ziegler, Schridde, and Maximow consider them as emigrants, attracted by chemotaxis. 248 Biology of the Blood-cells cell that we see through the microscope in this situation. The correct attitude to adopt in respect to the study of chronic inflam- matory cytology is that of deciding the cytoplastic stage which has been reached by any given cell, using the nuclear characters as a criterion of development along the phlogoblastic line. More briefly, the nuclear structure affords a clue to the direction along which the given cell is trending at the moment of fixation of the tissue, and not to the road along which it has previously travelled. The Eosinophile Cell 249 II.— THE EOSINOPHILE CELL. Varieties— Morphology — The granules, and their properties — Source — Functions — EosinophiUa and. eosinopenia of the blood and tissues — Source of the cell — — Comparative cytology. In every hundred leucocytes that pass by any given point of the circulation, we may expect one to contain granules intensely stainable with eosin. In some physiological states they may not be as numerous as this, and in others they are more frequent. A large number of morbid states are associated with increase or decrease of their numbers. As with all the other blood-cells, our curiosity is aroused as to whence these cells are derived, and while history tells us that they are supposed to come from a mother cell in the bone- marrow, it is only necessary to study microscopic sections of many tissues to convince ourselves that such supposition is extremely one- sided. Just as the lymphocyte of the blood-stream bears some relation to the lymphocjrte of the tissue, and is yet not always the same, so the eosinophile cell of the blood-stream is sometimes similar to the eosinophile of the tissue, but not in every instance exactly the same. In other words, the neutrophile leucoc3rte always comes from one series of cells, via the neutrophile myelocjrte, but the eosinophile leucoc5rte has a variable ancestry, and is rather to be looked on as representing a functional stage of more widespread cells. Varieties of Eosinophile Cell : — The eosinophile " myeloc3rte." The eosinophile leucoc5rte. The eosinophile cell of the intestinal mucosa. The eosinophile cell of chronic inflammatory tissue, including the eosinophile clasmatocyte. The eosinophile corpuscle of ocular tissues. The eosinophile cell of Hodgkin's disease. Morphology. — In each of these cells the all-important feature* * Arneth's method applied to the eosinophile cell " has proved to be of no service. ' 250 Biology of the Blood-cells EXPLANATION OF PLATE VII. 1-3. — ^Tissue lymphocytes. 4. — Ditto, showing wheel markings. 5. — Ditto, showing p asmoid change, while the external contour is unaltered. 6-8. — Plasma cells with swollen body ; 7 is dividing; the cell-body is dusky but|the nucleus is hyperchromic. 9. — Tissue eosinophile. 1 0. — Eosinoid lymphocyte. 1 1 . — Eosinoid plasma cell, with wheel marking. 1 2. — Lymphoblastic cell, with hyperchromic nucleus. 1 3. — Swollen connective-tissue cell, showing lymphoblastic nucleus and nucleolus. 1 4, 1 5. — Adventitial cells, rich in grano- plasm. 1 6. — Marchand wandering cell, with rather oxyphilic cell-body and undergoing division. 1 7. — Degenerated vacuolated lymphocyte. 1 8. — Leucoblastic adventitial cells, having analogies with the pulpar cell. 19. — Giant cell undergoing division. 20. — Young fibroblastic lymphoid cell. 21 . — Giant endothelioid cell or mesenchymarcell. 22. — Smaller form with caryolytic nucleus ; the cytoplasm is more basophile. 23. — Megakaryocyte, showing the characteristic nuclear form, from a case of Hodgkin's disease. 24. — Another form, showing exudation of nuclear material into the cell-body. 25. — Lymphatic leukaemic leucocyte, stained to show Altmann granules and perinuclear halo (after St. Klein, Fol- hasm. Bd. x, Plate XIII). 26. — Leuksemio mast cell (after Pappenheim, Grundriss). 27. — Giant fibroblast. 28-30. — Hybrid mast-eosinophile cells (after Benacchio, Fol. haem. Bd. xi, Plate V). 31. — Hodara plasma cell. 32, 33. — Marschalko plasma cells (31-33 after Hertz, Fol. haem. Bd. xiii, Plate V). 34-42. — Various- forms of plasma cell (after Pappenheim, Atlas) : 34. — Lymphoidocytar form, with characteristic nucleus, nucleolus, and basophilic cell-body. 36, 36. — Macrolymphocytar form, with astrosphere. 37. — Young mesolymphocytar form, showing intense nuclear staining, deep basophilia of the periphery of the narrow cell-body. 38. — Mesolymphocytar form, with slight oxyphilia in the astro- spheric region, 39. — Microlymphocytar form, with wheel-marking in the nucleus. 40. — Macroleucoblastic form, showing the shadowing of the nucleus and deep blue cell-body. 41. — Micro! eucoblastic form. 42. — Leucomonocytar form, with characteristic nuclear outline, deeply basophile cell-body. 43-53. — Various forms, as seen in the lower animals (43-53 after Werzberg, Fol. ham., Bd. xi. ; 51, 52, after Kasarinoff, Fol. ham. Bd. x) : 43. — Mast cell, siredon pisciformis. 44. — Mast cell, second type. 45. — Eosinophile of emys lutaria, with round granules. 46. — With spindle-shaped granules. 47. — Eosinophile myelocyte with halo round nucleus and inter-granular oxyphile cytoplasm, ophiosaurus pseudopus. 48. — Eosinophile cell with sparse spindle-shaped granules and tigroid nucleus from lacerta viridis. 49. — Eosinophile cell with dense rod-like granulation. 50. — Large myelocyte, with rosette of needle-like granules round the astrosphere, from hemidactylus. 51 . — Pseudo-eosinophile cell of fowl-blood, showing a trace of polynuclearity ; the granules are spindle-shaped. 52. — ^True eosinophile leucocytes of fowl-blood. 53. — Eosinophile cell from beetle. 54-62. — Normal marrow cells (rat) stained by the vital brilliant cresyl-blue method, showing granules in the cell-body, dividing forms, etc. Magnification: 1-24, 27, 53, Zeiss oil-immersion lens, Oc. I2 ; 54-62, oil-immersion lens, Oc. 4 ; the remainder are more magnified than the first series. Stains : 1-24, 27, hsematoxylin and eosin, cells drawn from sections ; 25, Altmann's method ; 26, 28-30, 34-52, Panoptic stain ; 53, triacid stain ; 54-62, vital stain. PLATE ril. PH LOCOCYTES % m ^ ^ 1 2 3 m f ■^.. 8 9 %% § 10 11 ^ 4* r^^^ t? ^^ ^^^c=^ # i.*"^ i i) J^^. •) € tli^, 1> 42 ^'/-i. ^^■t^ 44 • ♦:rf;i .^^v •t^- ) Q .-l§S, F' '> Biology of Blood'Cflls 0. C, Gruner The Eosinophile Cell 251 is the character of the granules* which serve to render their detection in the blood-film or tissue extremely easy. The morphological characters need not be detailed. Suffice it to say, in the myelocyte form, the nucleus is " myelocytoid " in being single, reniform, oval, or slightly indented. If the indentation be deep, we could speak of a metamyelocytoid form. These nuclei stain feebly. The leucocyte form, on the other hand, has a bi-lobed nucleus which stains very intensely. Schridde considered that these varying appearances might be explained as the effect of obliquity of section, one lobe only being caught in some, while both are caught in the others ; on the other hand, the difference in the degree of chromatism could not be accounted for in this way. The granules stain an intense glistening vermilion red with eosin. With dark-ground illumination they take on a golden- yellow sheen and are very conspicuous. The speculations regarding their nature are intimately bound up with the question of the meaning of the eosinophile at all. Properties of the Eosinophile Granule. — (i) They possess an oxydase (Loeles) but no protease (Wiens-Schlecht^), and contain a haptophore group whose chemical structure is — NH^.f This is shown by the intense phenolphilic reaction obtainable with these cells, which indicates that the granules must constitute oxygen- centres from which the oxidation of leuco-bases can proceed. (2) They contain an aldehyde group (Weiss'?), shown by the fact that they give the furfurol reaction of Mohsch-Udransky, or the Reichel-Mikosch aldehyde reaction (violettblau). This indicates the presence of protein in the granule, and of a skatol grouping. (3) They give the pyrrhol reaction with paraminobenzaldehyde and HCl ;8 so they must contain a protein akin to melanin or keratin (Petry, Schlecht, and Ziegler). (4) They contain 11 per cent of iron, according to an analysis by Petry .^ (5) GoUasch found that the granules might give rise to Charcot-Leyden crystals in cases of asthma, and pointed out that the latter are identical with the * Arnold's plasmosomes. ' t The detection of an — NHj group is of importance in connection with the relation- ship of eosinophile to mast cell granules {see " Hybrid Cells "). It seems possible for the one to be converted into the other. Mast-cell granules need diamidobenzol or a-naphtyla- mine (benzol radicle) for their demonstration, but the staining is not specific (Loele). 252 Biology of the Blood-cells seminal crystals of Bottcher, which are composed of ethylene-imine, CjH^NH. (5) Ciaccio claimed to have demonstrated the presence of lipoid substance within the granules. (6) An extract of eosino- phile cells will give a marked oxydase reaction as long as it is not boiled.io (7) They contain no phosphorus (Petry), and are very resistant to solvents and ferments. (8) They react with adrenalin." Other Granules within the Eosinophile Cell. — Amoldi^ found glycogen granules in the tissue-eosinophile of the frog, rabbit, and child, and demonstrated that they were more abundant after a starch diet. He noticed that the character of the nucleus altered with the numbers of the granules. Mast granules are noticed in the circulating eosinophiles in leuksemic blood, and in the bone-marrow eosinophiles in certain animals. Such " hybrid mast cells " are referred to later. Source of the Eosinophile Granule. — ^There are two possi- bilities to consider. Either the material may be derived from within the cell, or it may be taken in from without. In other words, it is the manifestation of purely catabolic processes, or it may represent anabolic or anabolic-plus-catabolic changes. These may be tabulated as follows : — Formed from within — (a). From the cytoplasm. Benacchio has referred to a prodromal'* granulation occurring diffusely through the cell. Schwarz'* and Hirschfeld have considered that the neutrophile granule may become eosinophilic. (6). From the nucleus. Stephan^' described this mode of derivation in the case of Protopterus. Reicher,'' in an elaborate study of asthma cases, found that the basic derivatives of cell nuclei (purin bases, or pjrrimidin, pyrazin, pyrrhol, pyridin, etc.) might give rise to eosinophilic substance. Derived from, without — (i). From the proteins of food. Rous'' found this to hold good in the intestinal mucosa.'* (ii). Fiom. red cells. The haemoglobin of dissolved red cells was supposed to convert a neutrophile into an eosinophile granule (St. Klein, Fuchs). Weidenreich thought that the haemoglobin of dissolved red cells converted a lymphocyte into an eosinophile cell." Sacharoff believed that it was the parahuclein of the red cell which converted the neutrophile into the eosino- phile. The arguments in favour of an origin from red cells are : (i) That the eosinophile is more commonly met with now that f ormahn fixation is common ; (2) That the granules contain iron ; (3) That the ionized iron in the cell may be derived from the bone-marrow ; (4) That the chemical characters of the iron- protein compound (resistance to solvents and ferments, elastin-like reactions. The Eosinophile Cell 253 etc.) are opposed to relation to the haematin group (Petry)'. Against the view are (i) The fact that the glycogen granule is related in some manner to the eosinophile ; and (2) The facts of phenolphilia (q.v.). (iii). From injurious substances in the tissues (Kammerer^"). On this view the neutrophiles in an inflammatory zone take up specific bodies, convert them into eosinophile substance, and lose their phagocytic activity. Similarly in infection by worms, the toxic substances are carried away by these cells. (iv). From the chromatin of degenerated spermatozoa (Tettenhamer's explanation of eosinophilia in the testis). The Functions of the Eosinophile Cell. — This subject is almost as obscure as that relating to the lymphocyte. Speculations are rife, but facts are few. The first question of interest, and the most simple to decide upon, is that of the factors which bring about eosinophilia or eosinopenia in the blood-stream. Causes of Increase in the Blood (greater than 3 per cent of the white cells). Physiological States. — After food ; during childhood ; in 15 per cent of the healthy natives of Southern China. Pathological States. — Presence of macroscopic parasites (trichina, hydatid, oxyuris, ascaris, ankylostomum, taenia mediocannelata). Skin Affections. — Urticaria, zoster, pemphigus, psoriasis, eczema, etc. Nervous Affections. — Graves' disease, puerperal mania, acute mania, melancholia, epilepsy, tetany, hemicrania, asthma (9-22 per cent). Drugs. — Tuberculin, pilocarpine (Neusser, Falta, Eppinger : denied by Aschenheim and Tomono), secretin, fluid of hydatid cyst. The following miscellaneous conditions have also been mentioned by difierent observers : tuberculosis of lung associated with emphysema, subacute or chronic tuberculous lesions, leprosy, scarlet fever up to the third week, congenital syphilis, uraemia, cirrhosis of liver, chlorosis, myeloleuksemia (up to 7 per cent), carcinoma with metastasis in the bone- marrow. Causes of Diminution (less than -5 per cent). — Pulmonary tuberculosis (unless irregular suppuration is also present) ; in lymphatic leukaemia, in measles, in starvation (Opie) ; wherever there is neutrophilia. 254 Biology of the Blood-cells Eosinophilia as a diagnostic aid : Its presence may be used to distinguish between gout and tubercle of joints, between active malaria and typhoid, between scarlet fever and measles, between trichinosis and acute rheumatism. As a prognostic aid : The reappearance of these cells after a suppurative process indicates approaching convalescence. In osteomalacia it signifies that the case has a good prognosis (eosinopenia indicates the reverse). Eosinophile cells are met with in the following tissues : — In the wall of the intestine, especially after intake of fooa.* They are found round the bases of the Lieberkuhn follicles, are scanty in the villi and over the Peyer's patches. They ooze out into the mucus poured out into the lumen of the intestine. The cells are much more common in intestinal catarrh, appendical catarrh, and the " lower " grades of appendicitis. Between the epithelial cells of the bronchial mucosa. The periphery of the follicles of lymph-nodes ; sometimes they occur within the peripheral sinuses ; also in the connective tissue round the nodes (Opie). The periphery of the Malpighian bodies, especially if there is blood eosinophilia. The bone-marrow. The thymus (apparently the secretion attracts them). The hsemolymph nodes. Woltmann^a believed that they develop here during the disintegration of red ceUs, whose products are absorbed by the large mononuclears. In the interstitial tissue of the kidney, of the foetal thymus, of active guinea-pig breasts (Berka^*). Here the clasmatocyte forms, mono- nuclear spindle cells, are to be seen.^s Wherever there is break- down of epithelium and cells. The nucleins and purin bases may play a part. Causes of Increase in the Tissues. — Skin diseases show very well-marked local eosinophilia ; chronic tuberculous lesions ; the growing edge of cancerous growths. In tissues vmdergoing repair. Specially numerous in certain forms of appendicitis. After parenteral administration of protein, t After immunizing to anaphylaxis. After injection of tseniotoxin (Proscher). Organisms causing tissue eosinophilia of the conjunctiva : spring catarrh, diphtheria, staph, p. aureus, gonorrhoea, sporotri- chosis. Cysticercus. Tumours causing : epithelioma and rodent * Rous" thought these were the direct source of the eosiuophiles of the lymph, t See also Schlicht, M. ior3, p. 800. The Eosinophile Cell 255 ulcer. Lymphogranuloma, Acute myeloic leukaemia. Nasal polypus. [Local eosinophilia does not arise in follicular con- jimctivitis (B. ichtimanicus), trachoma, molluscum contagiosum (Pascheff22).] Organisms causing disappearance of eosinophiles from a tissue : t5^hoid toxin, streptococci, anthrax bacilli (C. P. Howard^e). Drugs failing to induce local eosinophilia : leucin, alanin, phenylalanin, asparagin, glycocoU. From all these observations it may be concluded that the eosinophile cell is amoeboid (Sansonow^^), (Stohr's phenomenon), is subject to chemotaxic influences, and may take up diphtheria bacilli (G. B. Foster^s), or staphylococci (Pascheff^s). Further, that it plays some part in the digestion of proteid, that it may make antibodies to certain organisms (diphtheria, tubercle), that it may furnish a body like enterokinase, and activate the glandular secretion of the intestinal wall (Simon, Pirone.is Schwarzi4). While much more definite information is needed on these points, it is advantageous to look upon a tissue-eosinophilia as meaning the presence of a definite proteia substance whose nature requires elucidation. The excessive numbers found at the peri- phery of the follicle remnants in a Hodgkin's gland, for instance, must mean the accumulation of noxious bodies in that situation, bodies which are probably of the protein-group, perhaps poly- peptids, perhaps more complex than these. On the other hand, bodies belonging to the fats may possibly have some relation to them, eosinophUes being observable in diseased mammary tissue. In the latter, the preponderance of lymphocytes, meaning as it does the presence of abnormal fats, would indicate that a protein constituent may have become liberated as well, and is being dealt with by the eosinophiles. Source of Eosinophile of the Tissue. — As with other tissue cells, the presence of eosinophiles may be explained in two ways. Either they have wandered thither, or they have been formed in situ. A third possibility, that some have wandered, and others have developed locally, is probably the correct explanation of most of these cell-aggregations. 256 Biology of the Blood-cells The arguments in favour of the eosinophiles being of histiogenic and not hemopoietic origin are as follows : — 1. Eosinophilia in the bone-marrow bears no constant relation to the tissue changes at the site of infection (Campbell Howard^o) ; similarly, the bone-marrow is not eosinophilic in cases of blood eosinophilia ; and vice versa (Leightonsi). 2. Amitosis can be observed in the tissue (cells with dumb-bell nuclei ; observations on osmic fixed material*). Plate VII shows some observations made on inflammatory tissue, exemplifying the gradual transition between lymphocytiform through leucocytoid to eosinoid forms. In some instances the cell-body takes on a diifuse eosinophilia, in others definite granules can be detected. The amoeboid nature of these cells is also well shown by the elongated processes. The mitotic forms are shown by hyperchromia of the nucleus and even the presence of diasters. Conversion of lymphoid cells into eosinophiles has also been described by others in non- inflammatory tissues, and in the bone-marrow. The mononuclear forms are called a-(micro)myelocytes. 3. The occurrence of eosinophile corpuscles in tissues indicates the possibility of local formation. 4. The blood is full of lymphocytes in lymphatic leukaemia, but the exudate of an inflammation arising during the course of that disease fails to show lymphocytes. Neutrophiles occur instead. Tissue eosinophilia therefore does not necessarily demand blood eosinophilia as well. The arguments raised against the view are : — t. The cell-increase in the blood in cases of asthma, e.g., is quite enough to account for the tissue increase. 2. There are quite enough eosinophiles in the blood at any time to accoimt for local emigration. 3. Opie32 claimed to have observed their diapedesis. 4. There is marked eosinopenia of the blood after an asthma attack (Heinecke, Deutschmann). 5. Naegeli denied the possibility of their arising from endo- thelial cells. * Denied by Schridde. The Eosinophile Cell 257 In relation to the third, intermediate view, it may be pointed out : — 1. That there is no reason why local or tissue eosinophilia and blood eosinophilia should not both be produced by the same cause. 2. The evidence offered by a study of cytometaplastic processes in the tissues makes it perfectly obvious that certain tissue cells might just as easily make eosinophiles under the influence of a pMogoblastic stimulus as the hsemopoietic cells of the bone-marrow make them in the ordinary processes of life. The tissue lympho- cyte, which partakes of the characters of a microleucoblast, or micromyeloblast, may readily undergo metamorphosis into an a-micromyelocyte, and finally appear as a tissue-eosinophile. Whether the chromatin of the nucleus remains the same or not is imessential ; the myeloc5rtic chromatin has a different composition and a different morphological arrangement, but may acquire its new characters by a perfectly continuous series of metabohc processes which are not necessarily either advance or regress, although some might take the view that an anaplastic phase is the first, and the metaplastic change the second stage in the process. Further, it must be added that the tissue eosinophile is not for ever debarred from entry into the blood, and that some of the uninucleate eosinophiles of the normal blood* may have been derived from the tissues and would be distinguished from the bone- marrow myelocjrte chiefly by reason of the large size of the latter. Comparative Morphology of the Eosinophile Cell. — ^The eosinophile cells met with in the blood of the lower vertebrates are of considerable interest by reason of the bizarre forms which the granules assume. In the fish, eosinophiles are seldom seen, and do not present the vivid features noticed in the mammal. Carassius auratus, as described by Werzberg,'* shows cells of moderately large size, with a relatively very small nucleus (almost myelocytoid in structure), varying in form from short to long oval, and slightly indent forms. The granules are more numerous toward the centre of the cell, are of uniform size, moderately numerous, and stain rather feebly. They are, however, much larger than the neutrophile granule and are somewhat highly refractile. Reptile blood is characterized above all things by the absolute pre- dominance of eosinophilic cells, which vary greatly in form and size in the different species. They are usually mononuclear, but in the tortoise and lizard also include polymorphonuclear forms. The following classification Described by Weidenreich. ^ ^ 17 258 Biology of the Blood-cells given by Werzberg is of interest: — (A) Very large cells whose cytoplasm is quite filled with short polygonal granules. This group includes {a) Cells with a small round or oval definitely excentric nucleus, which stains deeply (grass- snake, emys, anguis fragilis, lacerta) ; (b) Cells with a larger, often indent or even polynu clear central nucleus (tortoise, lizard, newt). Some few animals have blood which contains both these varieties. The density of granulation is variable. (J5) Still larger cells, whose nucleus is always large, vesicular, amblychromatic, while the cytoplasm is characterized by the presence of but few granules, which are often arranged in a stellate fashion, are elongated or fusiform, and sometimes clubbed (see Plate VII). The nucleus is (a) Rounded or slightly indent, (6) Polymorphous (skink, chameleon, iguana). Lacerta viridis is the only reptile which contains cells of both A and B varieties. The relations between these forms is assumed by the author quoted as : Ba ages into Bb, gives rise to Aahy mitosis, and the latter to ^6 by ageing. It seems doubtful, however, whether these eosinophiles are truly analogous to the human form, and the peculiar stellate structures appear to be of very peculiar nature, and must subserve an entirely different purpose from that of the eosinophile of the mammal. The blood of Amphibia contains eosinophile cells which are more closely allied to the mammalian cells. In the salamander, they are usually poly- morphonuclear ; in proteus, mononuclear forms are also found. Astrospheres and centrosomes are sometimes very clearly demonstrable. Spelerpes, the tree-frog hyla, and the triton have no eosinophiles. In the frog, the granules appear to be intranuclear, but they really lie in little vacuoles in the cytoplasm. The polynuclear forms are prevalent in the old animal, the uninucle'ate forms are prevalent in the young. The granules are of regular size, round, rather pale, and variably dense. They are quite numerous in the adult. Arnold^' described occasional forms with rod-shaped granules, but as a rule, the regular spherical shape is a characteristic difference from the reptile eosinophile. It is possible that some of these eosinophiles are derived from the lympholeucocytes. The eosinophile of the Birds differs little from that of the mammals, and hardly requires special description. The nucleus is frequently bi-lobed, the two lobes being connected by a slender thread. Each portion exhibits markings which correspond to those of the mammalian myelocyte. The cell-body is oxyphile, and completely filled with very fine, intensely oxypMle granules. They occur in very small numbers. The existence of a cell in birds resembling the reptilian cell, but called pseudo-eosinophile by Kasarinoff,^* must be called attention to, as it would naturally be classed as a true eosinophile from analogy with the forms described above. These cells are crowded with rod-shaped, brightly eosinophile "granules" arranged in all directions, like iron-filings before a magnet is placed against them. The nucleus of such cells is double, or even treble, and has a structure like that of the mammalian neutrophile leucocyte. The fact that they preponderate in the avian blood, and that they are subject to the same chemotaxic influences as in the neutrophile of mammals, justifies the decision of the author quoted, which relegates these cells to the polymorphonuclear series of the mammalian leucocyte. , The Mast Cell 259 III.— THE MAST CELL. Varieties — ^Morphology of the mast cell of the blood ; of the tissue — Occurrence — Function — Chemistry of the granules — ^Views as to nature — Source — Compara- tive C3rtology. Just as the blood contains only a small number of eosinophile cells, so it contains very few mast cells (about the same percentage), while the tissues show them much more frequently. There is this diifer- ence, that the content of the tissues in mast cells is considerably less than holds for eosinophiles, and the tissues in which they occur are themselves largely morbid. The Varieties of Mast Cells — I. In the Blood. (i). Poljmuclear mast-leucocjrte (guinea-pig type). {a), a- and /3-pseudo-mast-leucocytes. (6). Mast-myelocytes. These are cells with broad c5^oplasm, sub- oxyphile reaction, and immature granules. Some of them are immature leucocytes (with specific granules), (ii). Mononuclear mast-lymphoc5d:es (rabbit type). {a). True blood mast cells ; y-mast-leucocsdies. These are cells with narrow cytoplasm. The granules vary in size ; these are lymphocytes which have undergone mucoid degeneration, and are not specific (include mononuclear and polynuclear micromyeloblasts). The granules are sparse. (b). Pathological blood mast cells, or myelo- leuksemic mast cells. The granule here is of the nature of an altered primitive azur-granulation. 260 Biology of the Blood-cells 2. In the Tissue. (i). Amoeboid polyblastic mononuclear forms. (a). Of spindle shape, rich in cytoplasm and granules. (b). Of lymphocytoid character, rounded forms with narrow and medium amounts of cell-body. This group includes the plasma mast cell of Krompecher (the lymphocytoid mast cell of EhrHch). (ii). Fixed " sessile " clasmatocyte forms of spindle or plate-like form. MorphologY of the Mast Cell of the Blood. — Outer form. — The size is variable, usually from g-12 fi. The shape is rounded. Cell body. — The spongioplasm is foamy or vacuolated, but is very scanty in amount. The granules are intervacuolar, and average about a micron in diameter. They possess the chemical characters detailed below. There is no visible astrosphere. Nucleus. — Central in position, variable in shape. Typically, it is like a clover leaf, being deeply indent, almost polynuclear. Less indented forms occur, as also forms with a rounded nucleus (lymph- oidocytoid form). With the usual stains, the nucleus has only a feeble affinity for dyes. Nucleolus absent. This cell occurs to the extent of -47 per cent of the white cells in 60 per cent of people. It is said to vary inversely with the eosinophiles. It is frequent in leukcemic blood,37 but here the type of cell is pathological, the granules being extremely soluble in water. It is increased in number in cases of staphylococcic infection (Levaditi), after the injection of p3T:odin, hemialbumose (Levaditi), colchicine, tuberculin, phrynolysin, milk, cancer extracts ; in cases of moribund cholera, severe malaria, acromegaly. The mast cell myelocyte is probably a degenerate form, and not a parent of the mast cell of the blood. It is really a dead or djdng cell,38 because (i) There are no transitions from a coarsely granular pseudo-mast ceU myelocjrte to a pol3Tiuclear cell ; (2) Basophile ancestors of the pseudo-eosinophile cell exist, but the granules are The Mast Cell 261 fine ; (3) The colour reactions are different ; metachromatin is basophile ; the granules do not stain with methyl green ; retain alcohol but not water or glycerin ; stain with rhodamin-S. The hybrid mast cell has been referred to in connection with the eosinophile. Morphology of the Mast Cell of the Tissue. — Size : Variable ; up to 22 ju. Shape : Polymorphous. Sometimes spherical, sometimes ovoid, sometimes club-like, or spindle-shaped, with long pseudopodia. The older forms tend to be angular. Contour : Clearly defined. Cell body : Abundant, with a foamy or vacuolated structure. Contains metachromatically-staining granules which are more soluble in water than in the case of the blood mast cell. Astrosphere : Present ; two centrioles have been described as present in it. Nucleus : The position varies according to the shape of the ceU as a whole. The shape is ovoid. The nucleus does not stain metachromaticaUy. Chromatin, abundant, deeply staining. It is arranged in clumps, amongst which vacuoles may be seen (Weidenreich). Nucleolus : Absent. Mitosis : This was described as occurring in the guinea-pig ceU by Jolly ; in the rabbit, hedgehog, and dog bone-marrow by Maximow. The variants of this cell are numerous. They have been described according to their position, though it does not follow that they are really of various distinct orders. Thus, in the muscle, the cell has the form and diameter of the muscle fibres amongst which it lies. In the cellular tissues, the cell takes on the form of the clasmatoc3rte or adventitial cell with which it is identical, according to Weidenreich.38 The tissue mast cell is met with in the subcutaneous cellular tissue, especially in urticaria pigmentosa (Unna), miliary vesicle (Unna, Michaelis), vesicle of erythema multiforme, lupus, epithelioma, rhinoscler(3ma, rhinophyma, and many other skin conditions ; near the blood-vessels of tumours of cerebral cortex ; in cases of general 262 Biology of the Blood-cells paralysis of the insane ; in the connective-tissue septa of organs, in the bone-marrow,39 in the testis of the horse, rat, pig ; in the spleen of lower vertebrates ; in the muscular tissues of the root of the tongue of the bat. It is met with in chronic infiammatory exudates in many situations, e.g., at the edge of the infiltrated tissue in many forms of appendicitis. In colostrum^o and other exudates.sf The Function of the Mast Cell. — The polymorphous shape of the cell body, the manner in which its processes are observed to probe into the interstices of the tissue in which it lies, strongly suggest an amoeboid property on the part of this cell ; its accumula- tion in certain tissues (urticaria pigmentosa) suggests that it is amenable to chemotaxic influences ; while the wide distribution of the type through the animal world suggests its possessing some definite importance. Fahr considered that the mucinous granule exerted bactericidal properties. Unna*! believes that the tissue mast cells form centres of storage of oxygen, especially in the vicinity of the blood-vessels, somewhat as the eosinoplule cell behaves in the blood. It is possible that the oxygen of the oxyhaemoglobin in the circulating corpuscles may be stored up by means of the mast or other granides in its passage through the tissue spaces. The mast granule itself is devoid of catalase, but contains peroxydase, so that a catalyser is necessary in such tissue spaces as those in which the mast cell occurs. The oxygen is given up to the plasma as the corpuscles pass through the capillaries, and is re-activated by the mast granule preparatory to its distribution to the cell-protoplasm. This theory may hold good to the extent of an accidental occurrence ; the paucity of mast cells in any given tissue indicates that these granules cannot be the main agent in the oxygenation of the tissue cells. The Mast Granule. — The granules of the mast ceU are of large size, spherical, and stain metachromatically with certain dyes. With toluidine blue they appear dark red. They are much more basophile than the nucleus. The solubility of this substance in various agents has been much studied. Thus, they are unaffected by alcohol, are soluble in glycerin, salt solution, alkalies, and very soluble in water. Acids, The Mast Cell 263 such as osmic and chromic acid, destroy the staining power without dissolving the granules. Oxidizing agents diminish, and reducing agents increase, the metachromatic staining power. They contain no fat (Ciaccio),42 and no iron. Source of the Material. — ^The mast granule may be derived from the cell body, or from the nucleus or the nucleolus. If from the former, it would be regarded as evidence of cell degeneration. In favour of this are the following points : (i) The existence of the granules in lymphocytes which have turned plasmoid (Krom- pecher) ; (2) The staining reactions are those of mucin (stain with Mayer's mucicarmine, muchsematin, Bizzozero's gentian violet (Randnitz, Hoyer) ; (3) They lie in vacuoles. Against this view are the following considerations : (i) The granules are more resistant to water than mucin ; Schwenter- Trechsler considered them to be some other substance than mucin, but secretory in nature ; (2) Mitoses have been observed in them (Dantschakoff, Meirowsky^s) ; (3) The appearance of vacuoles is artefact, dependent on the solubility of the material in water. View that they are of Nuclear Origin. — Pappenheim'** considers that the granules are formed from the lipoid of the spongioplasm by combination with the basophile metachromatin .from the nucleus. This is a (mucoid) metaplastic process resulting in the formation and deposition of mucolecithid.^^ In favour of this view are the dye- reactions exhibited by the material.^s The granules are not grouped specially round the astrosphere. Considerations relating to the phenolphUic substance of Loele show that the nuclear excretion may discharge a basophile substance which interacts with the phenol- group to form a precipitate of phenolphUic granules, but on the other hand there must be some other factors at work to account for the difference from eosinophile granules (which are brought out by the same method of staining). Weidenreich believed them to arise by pigmentation of the nucleus. But they are not of the nature of chromatic substance. Meirowsky believes that they were derived from nucleolin, and might form precursors of melanin. On this view the mast cell would be a pre-chromatophore ceU. Purpose of the Granules. — As already stated, they have been 264 Biology of the Blood-cells regarded as centres of oxygen-storage. Schneider thought they might constitute reserve substance. EhrUch beheved them to be the expression of over-nutrition of certain of the connective-tissue cells from exposure to much fluid. Harris47 called the cell a mucino- blast because they could be traced to the hyaline cells, and might exhibit a crystalline appearance in their cell bodies. These various points require to be disposed of before the nature of the mast cell can be determined. EhrUch and Schridde believe the cell to be specific, arising by differentiation from a specific cell called a mast myelocyte. The chief evidence in favour of this view lies in the existence of mast myelocytes in the guinea-pig. Weiden- reich classified blood mast cells into those of " rabbit type " and those of " guinea-pig type." On the other hand, there are definite objections to the idea of a myelocyte form ; among them are the following : — 1. Histiogenic and blood mast cells only resemble each other in the staining reaction of the granules. 2. There are no promyelocyte and metamyelocyte forms of mast cell (Bennachio^s). 3. The leukaemic mast cell is probably of a different nature altogether. 4. The mast cells of one animal are practically indistinguishable from those of any other (save regarding the point raised by Weidenreich). Mast cells are only absent in fish. 5. Some plasma cells may contain mast granules. 6. Eosinophiles occur which contain mast granules (" hybrid mast cells "). It is more than probable that the mast cell is not an entity, but that these granules may appear in any connective-tissue cell,* clasmatocyte,'*9 plasma cell, monocyte, or wandering cells of any kind. For this reason, the cell is regarded as merely a phase in the life-history of certain blood cells. The lymphoc5rte of the blood- stream, for instance, may undergo mucoid degeneration of this kind under the influence of certain toxins (staphylotoxin, phrynolysin), * Cf. Audry's " isoplastic cells." The Mast Cell 265 and constitute a mast cell of the blood-stream (Proscher^o). In favour of this view is the fall in the percentage of mast cells with rise in eosinophOe content of the blood. The leukaemic mast cell may be derived by a similar change in the lymphoidocyte, or may pass on towards an eosinophile cell, and finish as an eosinophile myelocyte. Staflfel and Rheindorf believed that the mast cell of the tissue might turn into a pigment cell. Comparative Cytology. — ^The characters of this form of cell present remarkable uniformity through the animal series. Beginning with the amphibia (fish do not contain such cells), two forms occur : (i) A histioid form with fine granules of irregular size, and staining red-violet with Giemsa. The C3rtoplasm is broad. (2) A lymphocytiform type whose granules are scanty, coarse, and whose cytoplasm is narrow. These two main types are found throughout the vertebrate series. They are well seen in the horse. ^^ In the chick, they appear as early as the ninth day of incubation. KasarinofE described exactly isomorphous forms for the fowl, pigeon, Senegal finch. 266 Biology of the Blood-cells IV.— THE PLASMA CELL. Varieties — Morphology of the plasma cell of the blood — Occurrence m the blood- Table of blood-plasma cells — Occurrence in the tissue — The lymphoblastic plasma cell — The granules — Ancestry— Theories — Effect of plastic irritation of the adventitial cells — Fate of the plasma cell — Functions — Comparative cytology. The time-honoured view that the eosinophile and mast cell of the blood represent specific orders of cells, each with its own ancestry distinct from that of the neutrophile leucocyte and lymphoc5rte, has been considered incorrect enough to justify their being classed as " phlogocytes." In other words, we would prefer to regard them as the manifestation of certain phases of life of other body cells, and not distinct species. In a sense, they are accidental contaminations of the circulating blood, but this would be ignoring the possibility that their presence may actually be required here, although not possessing the same importance as when located in the tissue spaces. In classing the plasma cell with these others, we find it possible to demonstrate the logic of the above conception, in adducing evidence to show the narrowness of the view that this cell is a purely tissue cell, and itself specific. The plasma cell is foimd in certain tissues, represents a phase of development or metabolism of other cells, already known as " small round cells," " lymphocytoid cells," lymphoid cells," etc., and may pass on to other phases. It is unusual for it to make its way into the blood-stream, but under some circumstances does appear there, and is then called a Tiirk or irritation cell. Under abnormal circumstances, too, any of the existing orders of non-granular blood ceUs may undergo a plasmoid change, and lead to the appearance of cell-forms which must be specified by as many corresponding names. In this way we come to consider lymphoc5rtoid, macrolymphoc5rtar, microlymphoc3d;ar, lymphoidocyiar, macroleucoblastic, microleucoblastic, leucomono- c5rtoid, and lymphomonocytar forms. Any of these may imdergo amitotic division, and give rise to a corresponding daughter cell. The plasma cells of the tissue are of two orders : those of The Plasma Cell 267 hsemopoietic tissue, and those of inflammatory tissue. Following Pappenheim, who has done so much to unravel the intricacies and confusion arising from applying the same word to many forms of cell in haematology, we should classify these thus : — 1. Plasma Cells of Hemopoietic Tissue. — ^These signify " irritation." Occurrence : normal mucosa of alimentary tract, especially during digestion. In the spleen, especially during digestion (Hertzsz) ; also in old age, and in cases of intestinal cancer (Br6tz53). According to Pappenheim they may enter the blood as Tiirk cells.* (i). Lsonphalic cells. {a). Ljonphoblastic. Here come the so-called Schridde-Hodara cells foimd in the Mal- pighian follicles, in the intestinal lymphoid follicles, and in the conjunctiva, and tonsil. They are mobile. (6). Lymphoc3rtar. Such ceUs enter the blood in any case of splenic enlargement, (ii). Myeloic cells. (a). Lymphoidocytar. (b). Leucoblastic. 2. Plasma Cells of Inflammatory Tissue, and perivascular tissue. (i). Fibroblastic Unna plasma cells, (ii). Unna's daughter plasma cells. (iii). True plasma cells, or Marschalko plasma ceUs (poly- blastic). These arise from clasmatoc5rtes via l5anphocyte of the tissue ; are small, large, or Saxer in type. They give rise to (a). Large plasma mother cell with broad ceU- body. (6). Small plasma daughter cells. 3. Pathological Plasma Cells include those of myelomas composed of plasma cells ; those of leukaemiaf of plasma cell type. • But these are not the same as the plasma cells of the tissue, for they do not possess a "wheel" nucleus. Pappenheim's Atlas, however, shows that this objection is not always true. •f Gluzinski, Reichenstein, Foa and Michaeli, Lucksch. 268 Biology of the Blood-cells Pappenheim54 gives a useful table gathering together all the types : — Waldeyer's Plasma Cell. Ehrlich mast cell Basophile wandering ceU Unna's strongly basophile plasma cells (collective) Schridde plasma cell Marschaiko TRUE PLASMA CELL Fibroblastic plasma cell Unna's histioid plasma cell (limited term) The true plasma cell comes from a microleucoblast or micro- myeloblast. The fibroblastic cell comes from a fixed connective- tissue cell. Morphology of the Plasma Cell of the Blood. — Size. — Variable ; between 5 and 14 j" (average 8'5). Shape. — Rounded or oval. Cell-body. — Extremely basophile, staining a deep blue with the panoptic stain. The spongioplasm is very clearly seen, largely because of the vacuolation present. But the granoplasm is more abundant. With triacid, the cell-body stains a dull brown. Granules. — Azur granules are rare.^s but have been described. Nucleus. — ^This stains very deeply. It is excentric, oval or rounded, and varies in structure according to the type of cell.* {See Table opfosite). Nucleolus. — Occasionally seen. Astrosphere. — Conspicuous. Degeneration Forms. — [a) With fat vacuoles ; (6) Vacuolar generation, producing a " foam " cell with vesicular nucleus. The granoplasm has altered, (c) Appearance of hyaline spherules ; {d) Appearance of phagocytic inclusions (red cells, e.g.) ; (e) Cyto- lytic forms, or Klein-Gumprecht shadows. Mitosis. — Mitotic division is not observed, but amitotic changes • Schridde ' • only recognizes lymphoblastic and lymphocytar forms. The Plasma Cell 269 3-^ t~ e 9 O u u A S S "SoJa ^ i^ - "> !3 h ■^ O P. V o J3 ■a o B A ■a « •a o 6 O "O XI S o< O 0> A ° J3 S « J3 t» O + CO I-) O A CQ O >-) PQ <: H e.-3 o o I" „ I 3 ^ ft A a Cll ■a a a + ^ O o V o -a ■ a a o A J) 60 5 •aii-9-3 3 fa M C "O — , o >, g- S 2 S 13 O i " en ^ n o " ^ o §•■■2 1,2 •3 >< 9 o a Id A 0) ft C ■a o ?! ^ m o B a " •a ^ (U .a i-H O §0^2 M S o rt + s- « — --3 -S bo rt n c; Is a i u *2 O £3 O o « + o "I i « A 3 ■3 .a fl si ^ ftS .S -g 6 o + u ft .a .3 >< w w o ^ n n j3 rn ft • M S S- •a O a O «j n 4 B .•§•■ !3 li" S ft 3 270 Biology ot the Blood-cells can be encountered. The cell-body then appears narrow, and stains deeply. The cycle of division must be a long one, as otherwise it would escape notice during fixation. The result of division is a plasma daughter cell. Occurrence in the Blood. — They have been found in the capillaries of the liver (Wallgrens^), in the vena cava of rabbits (Carletti) ; in man suffering from malaria, scarlet fever (ii per cent in one case of Hertz'ss2), and whenever the spleen is enlarged. They may also appear in the blood in association with inflammatory or infective leucocytosis. Morphology of the Plasma Cell of the Tissue,— Outer Form. — ^The absolute size is variable. The shape is oval or round, cuboidal, or regularly polygonal, or elongated. Contour rather ill-defined. Cell-body. — Is abundant on one side, relatively abimdant in any case, and exhibits a foamy structure. It is extremely rich in amorphograniilar granoplasm, and stains strongly basophUe* with polychroma methylene blue, thionin or toluidin blue. It is specially dense towards the periphery. The paraplasm is abundant, chromo- phobic, and most abundant in the region of the astrosphere. Granules. — These are irregular clumps of cytoplasm. They stain blue with toluidine blue. Schridde or Altmann granules occur towards the periphery. Gentianophile granules are present. Perinuclear Zone. — ^Well-marked. It is formed of minute fluid drops which increase in size towards the periphery. The inter- mediate material is basophile.f According to Wallgren, this zone can be subdivided into a dark inner and a slightly pale outer layer. Astrosphere. — ^Well marked. Wallgren^'' observed in it three centrioles connected by filaments. Nucleus. — Position, excentric, " tucked away in a corner." Outer form : rounded or oval in shape, relatively small in size. Chromatin, abundant, darkly staining, but showing a characteristic wheel-structure. Nucleolus. — May be one, or two. If one, it is central. * Because; young. Compare with the basophile myeloblast, larger lymphocytes, and sarcoma cells. t Hofmann." The Plasma Cell 271 Mode of Division. — By amitosis. Pappenheim.se Unna, and Schridde record occasional mitotic division. The basophile grano- plasm disappears during the amitotic stage. The above description applies to the true plasma cell, type Marschalko. The following forms of tissue plasma cell may be also described : — Morphology of the Schridde-Hodara* Plasma Cell: better named the lymphoblastic plasma cell. Outer Form. — The ceU is very large, and rather polymorphous in shape. May tend to a spindle form (amoeboid movement ?). Cell-body. — Cytoplasm narrow, but sometimes abundant, especially in senile forms. Stains dark blue with methylene blue, bright red with pyronin. An astrosphere is present in some instances. Nucleus. — Relatively large, central in position, sometimes almost structureless, at other times showing coarse nodal markings. Amblychromatic. No wheel structure. Nearly fills the cell. Perinuclear Halo present. Nucleolus present. The plasma mast cell of Krompecher is a lymphoid cell that has undergone mast and plasmoid change simultaneously. It may be compared with the pigment mast cell of Staffel, and the hybrid mast cell of leukaemia. The Unna Daughter Plasma Cell is intermediate between the l5miphocyte and the large plasma cell. The Enderlen-Justi plasmoid connective-tissue cell is a fibroblast with a strongly basophile cell-body. The Granules of the Plasma Cell. — It is hardly correct to speak of granules in this form of cell, because they are not comparable with those of other blood-cells. The cytoplasm has a granular appearance without an ability to define discrete bodies in it. They are certainly not artefact, because they are visible in frozen sections of absolutely fresh tissue (Schridde). ^^ xhe substance • If there be any difference between the Schridde and the Hodara cell, it is that the former is derived from the lymphoblast, the latter from the pulp cell of the spleen (splenocyte) but perhaps these forms are really functional stages of the same kind of cell (Hertz"}.. Fappenheim treats them as identical. 272 Biology of the Blood-cells which imparts this appearance to the cell-body is found to be iron- containing (Harriseo), just as holds in the case of the osteoblast at the time that it is about to secrete bone. The iron in the plasma cell may therefore bear some relation to the formation of fibrous tissue secretion. Pappenheim believes the granoplasm to consist of paranucleoproteid. It is strongly acid, and readily soluble in saline. It may arise after the manner of a " sclerosis of the spongio- plasm." Supposedly lipoid granules were found by Proellsi in the astro- spheric region. The observation that these bodies were similar to those in the cytoplasm of macrophages led to the conclusion that the plasma cell is related to the tissue lymphocyte on chemical as well as on morphological grounds. Gentianophile granxiles and basophile (mast cell granules) have been found in these cells. Loele found much phenolphilic substance in the viciaity of the nucleus. The Ancestry of the Plasma Cell.— This has been the theme of an incredible amount of literature. Were it not for the impossi- bility of directly observing the processes of metaplasia, the divergence of opinions would have been obviated ; and although one can appeal to the appearances in various tissues to advocate the view that any tissue cell may undergo a plasmoid change under suitable circumstances, the difficulty remains that every observer of such phenomena would not interpret them alike. The following are the views which have been put forward from time to time : — I. That it is a connective-tissue cell, or fibroblast* — Pro : The finding of all transitions in the tissue of a soft sore, hard chancre, acne, rhinoscleroma,t rhinophyma. Con. : The following contrast : Plasma Cell Connective Tissue Cell Granoplasm very abundant Spongioplasm very abundant No relation to fibrous tissue Immediate relation to fibrous tissue formation formation Morphology characteristic Morphology unlike the plasma cell Chief constituent of granuloma Chief constituent of fibrosing tissue • Unna, Leo, Ehrlich, Jannovics (partly), Enderlen and Justi (partly), t Sherrington and Balance. "The fin(\ing of all gi-adations bftween follicle lyniphoc\-te3 and plasma cells" (p. ::73). /■/i;. ()S,— Portion of ax Intestinal I^ymphoid Follicle, from a case of Typhoid Fe\'er. Notice the variability of these mononuclear cells ; man>- are elongated and are gre\- in colour, while others are definitely round and come out intense black in the photosraph- (Oc. 2, Obj. A). Fact- /. The Plasma Cell 273 It will be evident that these distinctions cannot be emphasized too strongly. 2. That it is a lymphocyte* If so, there are the following possible ultimate sources : — (a). Emigration from the blood.f (i). Blood-lymphocyte, (ii). Large mononuclear leucocyte. { Against this view is Pappenheim's observation that plasma cells do not occur within the follicles of the spleen, but in the pulp and at the periphery of the foUicle. This indicates that they have some closer relation to the pulp tissue. The lymphocytes of the follicle are permanently agranulopotential. This is a striking fact in the case of the follicles of the appendix. (&). Local formation from the endothelium or ■perithelium (lymphoid or lymphocytoid polyblasts), whether blood or lymphatic,§ or from wandering lymphocytes, or from the lympho- C3rtes of a Ribbert lymphoma. || Pro. — ^The finding of all gradations between follicle lympho- cytes and plasma cells in such a lesion as the inflamed foUicle of the intestine in typhoid fever. {See Fig. 68.) Further, the inconstancy of the characters, and the difficulty of certainly distinguishing the (e.g., daughter-) plasma cells from a lymphocyte. Schridde has suggested that the origin from this source must be pathological, because of the occurrence of forms with two, three, four, or even six nuclei. Con. — ^The formation from a lymphocyte has never been observed. The Malpighian follicle should be studded with plasma cells, and it is not. On the other hand, knowing as we do that the tissue lympho- cyte is not always a member of the lymphatic series, but should be called a micromyeloblast, there are found certain arguments for believing that the tissue plasma cell is myeloblastic in origin : * Baumgarten, Marschalko, Deganello, Benda, Dominici, Helly, K. Ziegler, Neisser. t Marschalko, Maximow, Schridde. X Krompecher, Schottlaader, Schlesinger. § I.e., adventitial cell. II Jadassohn, Enderlen and Justi. i8 274 Biology of the Blood-cells (i) Its absence from the lymphoid follicles of the spleen, intestine, conjunctiva; (ii) The existence of plasma-cell myelomas (myelo- plasmocytosis) in the bone marrow; (iii) The association of Marschalko cells with chronic inflammatory cell infiltration ; (iv) Altmann granules occur equally in lymphocytoid and myelo- blastoid cells (Wallgren, Butterfield, Klein) ; (v) Preformed lympho- cytomas never give rise to plasma-ceU tumours. (c). Both by emigration and by local formation (Maciesco- Jalenska63). They are very numerous in the lung in cases of caseous tuberculous pneumonia, but absent in fibrinous pneumonia. In this tissue they are perivascular, peribronchial, interalveolar, and subpleural. They occur anywhere where regeneration is proceeding. 3. That it is an altered adventitial cell (Marchand's clasmato- C3d:e). This view is reaUy covered by the preceding, for it must be supposed that the tissue lymphocyte is so derived. 4. That it is an altered endothelial cell (Rheindorf). This view depends on the close morphological resemblance between the cells as seen by sublimate fixation (Enderlen and Justi^*). 5. That it is a mere functional state of any kind of lymphoid cell, and merely means that basophUe material has been taken up or formed in excess. This is indicated by their reversion, for instance, to iymphoc3H:es after the inflammatory stimulus is over (Grimani). We should thus picture to ourselves a periodic flooding of the ceU-body with nuclear acids, leading to the obscuration of the cytoplasmic structure. Against this theory are the facts that : — (a). Basophilia is not due to functional irritation, but to the absorption of the substrate (Enderlen and Justi). (6). The cell may be in a pathological state — sclerosis of the spongioplasm. Expressed in a nutshell, the Schridde cell is the plasmoid large lymphocyte, while the Marschalko cell is the plasmoid micro- leucoblast, arising in the spleen, e.g., from the granulopotential lymphoid cells of the pulpar tissue.es The Plasma Cell, 275 The following chart may express the possible effect of a plastic irritation of the cells covering in the walls of the capillaries : — Adventitial cell Myeloplastic stimulus Saxer primary wandering (Lymphoidocyte) i Tissue l3^mphocyte (micTomyeloblast) cell Marschaiko plasma cell -!■ Micro- lymphoid cell Unna's daughter plasma cell i Lymphoblastic stimulus Lymphoblastic macrolymphocyte Tissue lymphocjrte i Direct change Ljrmphocytoid Schridde into plasma plasma cell plasma cell ceU \ i May enter blood as irritation cell Functions of the Plasma Cell. — ^The main purpose of the plasma cell appears to be connected with the deposition of fibrous tissue in the affected area. Whether it has anything to do with the formation of antitoxic substances (Maciesco-Jalenskass), or not (Wolf^e), whether it serves to transport substances away from the zone of iaflammation or not (Wolf), is difficult to establish. The analogous appearance to that of the pancreatic or other secretory gland cell during the resting stage may be drawn attention to as indicating that the granular appearance is due to the storage of substances within it which are of use when discharged into the surrounding medium. That these cells possess migratory powers (Alegnoss) is easily shown by the observation of the epithelium of the tonsil or intestinal villus (Joannovics and Pirone^s). The duration of life is variable. Schridde believed them to be very long-lived, and certainly from one's observations of inflam- matory infiltrations of surgical tissues, and especially such a condition as linitis plastica, one would be prepared to beUeve that they remain apparently stationary for months. Fate of the Plasma Cell. — ^The cells may enter the blood as Tiirk irritation cells, as already mentioned. They may become fixed connective-tissue cells, for they disappear from an inflammatory 276 Biology of the Blood-cells focus as scar formation takes place. They may undergo regression to lymphocyte-like cells after the plastic stimulus has passed off. Or they may undergo the following degenerative changes : — 1. Cells with feebly staining c5d;oplasm, of any grade up to complete loss of basophUe property. Nucleus remains clearly defined. 2. Cells with normal cytoplasm, but a large nucleus which has lost its wheel structure and chromatin network. 3. Cells with vacuoles (Wolfee). 4. Cells with hyaline, granular or chromatic degeneration. The intracellular Russell bodies are considered the result of myelin degeneration of the ceU-substance (Millers?). 5. Fragmentation of the cell-body with the appearance of free nuclei in the tissue. SCHEME SHOWING THE FATE OF THE PLASMA CELL. Lymphoblast y Intermediate stages- Pulp lymphocyte T *Splenocyte-' * Sclilesinger. ' Granular degeneration .Chromatinic degeneration -Russel body formation Anaplastic change into a tissue lymphocyte •Fixed connective-tissue cell ■Epithelioid cell ■Macrophage ^Daughter plasma cell Bits of cytoplasm in lymphatic clelts Formation of free nuclei in tissue clefts •■Anaplastic change into a tissue lymphocyte Comparative CytologY. — The most valuable contribution on this subject is that by Downey,7o who investigated the ganoid fish polyodon, amblystoma, frogs, the garter snake, various mammals, and man, using specimens which were to all intents and purposes The Plasma Cell 277 quite healthy. This author found that plasma cells are abundant in certain definite regions of cold-blooded animals : thus, in the lympho-renal tissue of polyodon, in the mesentery of the frog, in the lung of the garter snake. In all cases they were formed from the clasmatocytes. He concludes that the various types are merely functional conditions of the same species of cell, and that a descrip- tion of their cytology is no more than one of the cytology of other hsemopoietic cells with the characteristic plasmoid change super- added. 278 Biology of the Blood-cells v.— THE CLASMATOCYTE. The Clasmatocyte and other purely connective tissue cells* — The giant celL The clasmatocyte, mesenchymal or adventitial cell appears in many forms. As shown by the method of vital staining first described by Goldmann.^z the same ceU comes to notice as a " pyrrhol ceU," which is not only found in chronic inflammatory tissues, but also in the intestinal waU, and interstitial tissues of glandular organs. This cell has a variable shape, being sometimes elongated into a spindle form, at other times exhibiting a branching form as if it were amoeboid. The ceU-body is rich in granoplasm, and dark or dusky in appearance. Its contour is clearly defined. There is never any metachromatic staining. The nucleus is rather large, dark, irregular, and usually shows dense chromatic structure, though leptochromatic forms occasionally occur. Transition forms between this and a fibroblast may be observed by the method of vital staining. Strictly speaking, this cell would be classed as a primordial cell, and the remarks made in Chapter I. would become applicable to it. {See Plate I, i ; Plate VII, 6 and 58.) The Giant Cell appears in various forms. The most important in connection with the haemopoietic tissues is the megakaryocyte already described. This occurs typically in the bone-marrow, but is also found in the spleen under certain conditions, and appears in the lymph-nodes in cases of Hodgkin's disease. The multiple nuclei may be the result of pluripolar mitosis, or of fragmentation. The so-called foreign-body giant cell appears to be the result of fusion of endothelioid cells or monocytic forms, but even the mega- karyocyte may be, in some cases at any rate, a derivative of the primary wandering cell of Saxer. t * " stroma,'' " stromatic " cells. t See also Gruner, " Diagnosis of Morbid Tissues," Medical Annual, 1911, p. 116. Inter-relations between Various Phlogocytes 279 VI.— THE CYTOPLASTIC INTER-RELATIONS BETWEEN THE VARIOUS PHLOGOCYTES. The mechanism of inflammatory cell infiltration may be better understood by a consideration of the processes which occur in the interstitial tissue of any vertebrate (or even of an invertebrate). Following the plan of describing microscopic fields of action of the various processes which go to make up what is termed haemopoiesis, we may describe the appearances seen in the vicinity of any capillary blood-channel, whether it be in the cellular tissue or in granulation- tissue (Fig. 67). We have the lining cells of the capillary waU, which may be the only structure separating the circulating cells from the tissue elements. As a rule, we may regard the presence of an outer layer of cells as essential. These are the perithelial or adven- titial cells, characterized by a relatively large oval vesicular nucleus, whose chromatin is in the form of punctate markings near the nuclear membrane, and an elongated cell-body. They are usually in a resting state, but may be roused into activity by certain chemical plastic stimuli. It is feasible, for instance, that an excess of a body with an amidine grouping oozing through the vascular wall, disturbs the equilibrium of the perivascular cells, and makes them first motile (now dignified by the name of primary wandering cell of Saxer), and then acquire or manifest other potentialities. The facts shown by the histological study of any chronic inflammatory mass reveal that this potentiality is dual. In other words, the slumbering perivascular cell acquires hsemopoietic tendencies, and is either lymphoblastic or myeloblastic. The exact effect depends rather on the character of the stimulus at work or on the degree \vith which the exit of lymph (and with it, the deleterious substance) is interfered with, and the consequent degree of concentration of the noxa — whether or not it is sufficient to set the cytometaplastic changes in motion. 280 Biology of the Blood-cells In a field such as is being considered, then, we notice the propor- tions of the different cells present, the endothelioid cells, the lymphocytes, the micromyeloblasts, the leucocytoid cells, the lymphoblasts, the plasma, mast, and eosinophile cells, etc. In this way we can draw up a cell formula for the tissue, and seek for a relation between noxious agent and certain types of ceU-formula. Heart J SpX c e 71. 1 ■^: ■^'- J .^.JBone,- marrow _r LyTTVph/ t Lymph I Tissue. node b: 1 Fig. 6gA. — Diagram to show the Double Action of Noxious Agents on Tissues AND Blood-forming Organs. Eosinophilia. . . . eosinophile cells ; 1, 1, ], eosinotaxic centres (e.g., in tlie appendix wall» Hodgkin's node). These centres are shown the seat of aggregations of locally-fomied eosinophiles, with blood- eosinophiles intermingled. S, eosinophile cells distal to 1, 1, 1, passing at S into the circulation (tissue- eosinophiles in the blood). -> circulating eosinotaxic substance. 4, fibroblastic centre, excited by the preceding ; 5, centres of eosinophile proliferation in the bone-marrow, produced by the action of the circulating eosinotaxic substance. 6, blood-eosinophilia (some adnuxture with tissue-eosinophiles). 7, centres of possible simultaneous eosinophile proliferation in the spleen. The processes taking place in the zone of inflammation are not completely considered as long as that particular region alone is being studied, because there is really a circle of vicious action. Thus, a noxious agent may not only excite eosinophilia of the tissue in which it lies, but it may also exert an action on the bone-marrow in the direction of causing an increased production of eosinophiles there Inter-relations between Various Phlogocytes 281 also. These new cells are then attracted back to the area affected, and constitute blood-eosinophiles as opposed to the local histiogenic cells. The latter are the result of the powerful attractive power of the noxa for the eosinophiles anywhere in the vicinity of the diseased area, and their very presence may be the means of flooding the ZympK Fig. 69B. — DiAGKAM TO SHOW THE DOUBLE ACTION OF NOXIOUS AGENTS ON TISSUES AND Blood-forming Organs, Lymphomatosis. . . . lymphocytes and other lymphoid cells. 1, 1, lymphotaxic centres. 2, lymphocyte that has wandered to that point, entering the attractive force of more than one lymphotaxic centre at once. S, wandering cdls being drawn towards 1, 1. k, tissue eosinophile also attracted to the same focus. The drawing shows a small lymphoma formed round 1, 1. 5, excreta of the proliferated cells, exciting. 6, more lymphomatous proliferation. ~-> circulating lymphotaxic substance. 7, possible course^'of lymphotaxic substances. 8,' exit of the same, with lymphocytes, to next node or to lalood tissue is not necessarily acted on. 10, enlarged Malpighian follicles. 9 and 10 would not occur if the lymphotaxic material did not pass 7 or 8. In the aleilkaemic proliferation there is no passage of cells at 7, but the noxious material may excite 9 or 10, or both. tissue with metabolic products which themselves act in a baneful manner by exciting further cell-proliferation locally or at a distance. The cell-proliferation is peculiar to this extent, that the initial stages of the process are very vigorous, and promise to end in the 282 Biology of the Blood-cells same way as in any blood-forming organ. Yet they fail to do so, and deviate along lines ordinarily quite unknown in the last-named type of tissue. Cytometaflasia has taken place, and a neoplastic transformation has been the result, the " neoplasm " tending to pass into a mass of fibrous tissue in some cases, into a mass of inert structureless material in others, and so on. If the field of battle could be mentally limited to two adjacent capiUary channels with a viscid interstitial substance, we should picture the stream in each side of the field as consisting of blood-cells and plasma — containing lymphoblastic, eosinoblastic, and other plastic substances. The intervening material contains the attractive force for all these substances, and the surplus, having diffused through the area in question, passes out of sight, but ultimately comes in contact with blood-formative cells, and excites eosinophilia, lymphocytosis, etc., as the case may be. Migratotaxic substances would account for the mobilization of potentially wandering cells to this field of activity. Meanwhile, the adventitial cells have succimibed to the influence of the stimuli in their vicinity, and have undergone active proliferation, and their excreta may contain auxetic substances which incite local cell-metaplasia. Some of the cells so formed may turn into fibroblasts of different kinds, and ultimately produce a scar, or they may escape from the scene of action, or they may undergo degeneration, or pass along other lines of development (plasmoid, eosinoid, etc.). The diagrams on pages 280, 281 may make this clearer. It may be noted that there is no finality about the meta- plastic changes. It does not follow, because fibroblastic tendencies have appeared, and a quantity of fibrous tissue has been formed, that therefore there is no escape from the fibrosis or cheloid formation. It is well known that agents such as A;-rays, and certain bacterial toxins, may lead to the disappearance of scar tissue. Consequently we are faced with the fact that a chronically inflamed area, no matter how long a time has elapsed since its first inception, no matter how indolent it may have been, may be excited to resolve so soon as adequate lymph-flow from the affected area is assured, phlogoblastic substances have been removed, and anaplastic stimuli are brought to bear. Inter-relations between Various Phlogocytes 283 The following scheme more clearly indicates the inter-relations between the cells : — BLOOD Cytoplastic differentiation without division. Possible or doubtful connections. Mitosis. Amitosis. Fig. 70. — Chart representing the Inter-relations between the Phlogocytes. I. — Resting perithelial cell ; i ', Endothelial cell. 2. — Wandering cell of Saxer (pyrrho cell). 3. — Lymphoidocyte. 4. — Lymphoprimitive cell. 5. Monocyte (is double-ringed to show its subjection to inflammatory stimuli). 6. — Polyblast of Maximow, Schridde, and Neumann, f. — Lymphoblastic macrolymphocyte. 9. — Microlymphoidocyte. 10. — Micro- leucoblast. 11. — Monocytoid macrophage. 13. — Mesolymphocyte. 14. — ^Tissue lympho- cyte (one of these is doubled-ringed to emphasize its subjection to unusual conditions). 14', Leucocytoid microlymphocyte. i5.--Schridde-Hodara plasma cell. le.^^Large mononuclear leucocyte. 17. — ^Transitional cell. 18. — Promyelocytar eosinophile cell ; 18', a-micromyelocyte. 19. — ^Eosinophile cell. 20. — Mast cell. 21. — Senile leucoblast. 22. — Plasma cell. 23. — Older plasma cell. 25. — Rieder cell (double-ringed to show that it is abnormal to blood). 27. — Megakaryocyte; 27', Marchand wandering cell. 28. — Mesenchymal cell. 29. — Fibroblast. 30. — Foreign body giant cell. 31. — Giant cell with hollow nucleus. 32. — Caryolytic giant cell. 33. — Cytolytic giant cell. 34. — Epithelioid cell of Marschalko, Krompecher, Schottlander. 35. — Mast cell with plasma nucleus, Krompecher plasma-mast cell. 36. — Martinotti's desmoid pseudoplasma cell. 37. — Fibro- blastic plasma cell. 38. — Unna daughter plasma cell ; 38' , Plasma cell containing Russell (myelin) body. 39. — Atrophic plasma cell (granoplasm breaks up into dots) ; 39', Ditto, but naked nucleus. 40. — Large lymphocyte of Botkin, Deganello. 41. Cell in state of hyaline degeneration : found in chronic inflammatory processes. The spongioplasm and nucleus remain intact. 42. — Foam cell of oedematous granulation tissue. 43. — Polynuclear cell of inflammatory cell infiltration. 44. Michaelis' spherinucleate cell (undergoing pycnosis). 45. — Pseudolymphooyte of Ehrlich, which has lost its granules. Produced from 43, or 44, by cytorrhexis. 46. — Daughter myelocyte of Tiirk and Pappenheim. The connection from ringed 14 to 6 is due to Lindberg (Upsala Lakareforenings Fiirhandlingar, vol. xvi., No. 3). The connection from 3 to 11 is by vacuolation. The connection from ringed 14 to 18 is based on Pascheff. The connection from ringed 14 to ringed 5 is based on Weidenreich, Maximow, Schridde, Patella. 284 CHAPTER VII. THE CYTOPLASTIC PHENOMENA OF BLOOD-FORMING TISSUES. Section I. — (i) On Metaplasia in General — Meaning of the term metaplasia — Metaplastic changes in epithelium and skeletal tissues — Evidences of metaplasia in hsemopoietic tissues — Errors to be avoided in studying these tissues — Anaplasia — Transportation versus local manufacture — Metahyperplasia — The question of inventing artificial means of influencing the process — The study of cytoplasia is essential to a comprehension of tissue-metaplasia — (2) The Mechanism of Meta- plasia — (3) The Exciting Agents of Metaplasia. Section II. — Special Examples of Metaplasia in Hemopoietic Tissues— (^) Myeloid— (5) Lymphoid— (C) Megakaryocytomatotic— (D) Mast cell— (£) Plasma cell— (i^) Splenoid— (G) Sarcoid— (H) Erythroblastic. Section III. — Survey of the Hyperplastic, Metaplastic, Meta- hyperplastic, and Allied Processes in the Pulpar and Follicular Tissues. — The play between parenchyma and stromatic elements in different diseases — Schemata illustrating the causes of enlargement of («) lymphatic glands, (6) spleen. Metaplasia in General 285 I.— METAPLASIA IN GENERAL. (i). On Metaplasia in General — ^Meaning of the term metaplasia — Metaplastic changes in epithelium and skeletal tissues — Evidences of metaplasia in haemo- poietic tissues — Errors to be avoided in studying these tissues — Anaplasia — Transportation versus local manufacture — Metahyperplasia — The question of inventing artificial means of influencing the process — The study of cytoplasia is essential to a comprehension of tissue-metaplasia — (2). The Mechanism of Metaplasia — (3). The Exciting Agents of Metaplasia. I- — On Metaplasia in General. BY the term " metaplasia " is generally understood the process by which a fully differentiated tissue becomes converted into another allied and equally differentiated tissue-form, without the agency of an intermediate stage of cell-interpolation.* While this process is usually studied by observing the tissue as a whole, it is an advantage to replace the word " tissue " in the definition by " cell," and consider the individual cells as isolated units ; for it is in this way that the phenomena of metaplasia in the pulpar tissue (lymph-node or spleen) become much more intelligible, and the word " cytoplasia " appropriate, inasmuch as it emphasises the importance of studying cell metabolism before theorizing upon such diseases as pseudo-leukaemia, splenomegaly, or hyperplastic tuberculosis of lymph-nodes. The literaturei confines itself almost exclusively to those instances of metaplasia that are exhibited by epithelial tissues under certain conditions, and those occurring in skeletal tissues undergoing regenerative repair after injury. f Much attention has been paid to the former, because it was hoped that herein would lie some explanation of the development of carcinoma in epithelium. The further question arose, as to whether epithelium can undergo metaplasia into connective tissue and thus account for the occurrence * The transformation of one definite tissue into another which is functionally different from the first (Orthi). t Thus, Borst, Schridde, and many others, have written upon metaplasia in epithelium. In a recent article (March, igrs) by G. M. Smith, references to this subject are made, as if epithelium were the only tissue to consider in such connection. 286 Biology of the Blood-cells of a sarcomatous tumour in tissues apparently epithelial. This question has always been answered by a definite negative in the halls of orthodox pathology, and yet anyone who examines a microscopic section of a tonsil cannot fail to notice that there is so intimate an association between the so-called epithelium of the crypt and the primordial adventitial cell of the follicles, that a denial of an inter-relation between epi- and meso-thelium cannot be dismissed lightly. Analysis of the apparently similar metaplastic processes in epithelium and bone, reveals the existence of subtle differences between them, and the invention of terms to express these has become necessary. Thus we have the term " allomorphism " or " dysmorphism " applied to such a process as the conversion of a columnar into a squamous epithelium by mechanical agencies; " prosoplasia," where there is a pathological differentiation of one form of epithelium into another of higher type than that exhibited under normal conditions ; " heteroplasia " where epithehum is deposited in sub-epithelial tissues during either embryonic or later life. " Normoplasia " is the usual physiological differentiation of a ceU.* Ribbert objects to the word metaplasia on the ground that the so-called examples are really not distinct from any of the known processes met with in general pathology. The objection cannot be entertained by those who see in metaplasia and its allies the only true explanation of the multiform protean metamorphoses met with in the tissues we are considering. Indeed, it may be truly said that the seats of hsemogenesis constitute the most accurate examples of the processes of cytoplasia, so that it is easier to discuss them in connection with hsemogenesis than with any other tissue-changes. The familiarity of the reader with the changes set up in the course of repair to a bone after injury, or in response to inflammatory or neoplastic activity, nevertheless affords a convenient starting-point for a discussion of the hsemopoietic cytoplasias. The periosteum, for instance, is usually fibrillar, but has a natural tendency to form osseous tissue by passing through a phase * Thus, if oesophageal epithelium becomes keratchyaliu, this is normoplasia. If vesical or vaginal epithelium does so, this is prosoplasia. Metaplasia in General 287 in which the fibrillje are embedded in hyaline material, whose con- stituent particles (colloidal) become more and more dense by- successive aggregation until the staining properties become similar to, and ultimately identical with, those exhibited by osteoid bone. The deposition of lime salts through this material may be described as completing the change of the osteoid tissue into bone, but in truth the salt deposition and the aggregation of the coUoidal particles are reaUy one and the same process, so closely are they interdependent. The mutations which may arise are the following : Firstly, the dense hyaline tissue may lose its lime salts, and simul- taneously lose the power of staining to such an extent that the product is colourable by acid dyes even less than is the original hyaline matrix. The constituent cells lose their shape, become ovoid, larger, paler, and are enclosed in fluid lymph, and the material is now recognizable as ordinary cartilage. Secondly, after the osseous tissue has lost its lime salts, it may undergo liquefaction to a greater extent, and reveal the presence of fibril- lations through it, the fibrillar form having been reassumed by its constituent cells. Thirdly, the metaplastic process may be complicated by the concurrent existence of proliferation and of inflammation, as is well seen in such bone-diseases as syphilis, rickets, Paget's disease, chronic deforming arthritis. In each of these cases the complexity of the changes may be interpreted to be the result of the excreta, as it were, of the new cells themselves, modifying, as they might, the processes of regeneration in the original tissue elements. The dawning light upon colloidal changes in the human organism shows us with no uncertain signs that the appearance in a tissue of such bodies as amidine compounds, imido compounds, and even diazo-groupings, may bring about a long chain of sequent reactions which result in colloidal interchanges between cytoplasm and intercellular material, and are of the most profound significance in the problems of lympho- poietic cytoplasias. Turning now to the bone-marrow, we find this tissue to be the subject of a constant and definite sequence of metabolic changes {p. 199). The transformation of adipose into mucoid tissue, or vice versa, brings about the appearance and disappearance of " gelatinous 288 Biology of the Blood-cells degeneration " of the marrow. More constant than this is the process of atrophy of the fat cells with hypertrophy of the hsemo- poietic cells, and vice versa. The phenomena which take place within the cells themselves are genuinely metaplastic in character, and, as we have seen in the successive chapters of this book, are liable to manifest variations of detail according to the changes in the stimuh which may reach the haematic parenchymal ceUs in these regions, endowed as they are with " multivalent " or multiple potentiaHties. In this way we find a ready explanation for the varying appearances set forth in the literature as characteristic of the various diseases of the bone-marrow as a blood-forming organ. If such interpretation be allowable for the changes in the bone- marrow, it is equally legitimate for the other centres of blood- formation. As a consequence, we shall seek for strictly metaplastic changes in such tissues as the lymph-nodes, the lymphoid follicles disseminated through the body, and in the spleen. Seeking for such cytoplasias, we find them indeed. For, just as the last decade has performed the great service of throwing light upon the meaning and nature of the " small round cells " characteristic of the inter- stitial tissues, so we are able to understand those in the lymph-nodes and spleen more clearly now than a few years ago. The modem literature replaces the words " small round cell " with others that more definitely express their significance and purpose in the tissue, although it is one thing to pass over the short stage from the phrase quoted to "lymphoid cells," and quite another to pass the long educational journey which would enable us to pick out the cells, classify them into microlymphocytes, microlymphoidocytes, macro- lymphocytes, macrolymphoidocytes, splenoblastic lymphocytes, monocytoid cells, pseudoplasma cells, eosinoid cells, etc., and then count them out and write out the cell-formula that expresses the tissue- reaction to one or other toxin, or toxoid* That is one lesson which has to be mastered before we can intelligently produce artificial anaplasia in these cell-clusters, and finally bring about the cute (by fibrosis) of any lesion that we desire. The other lesson is easy to learn, because it is only one of recognition of a fundamental truth, * Benda suggested that grauulosarcoma was produced by a toxoid. Metaplasia in General 289 that all the cells of the blood-forming organs are neither similar, nor constantly or persistently the same in function, destiny, or origin. On this view the influence of new stimuli may lead a blood- cell parent to pass along a collateral line of development, and its progeny may acquire the habit of passing along this line, so that ultimately a tissue is produced whose cells are all different in type from the original. While the basis of such a conception is afforded by careful preparations of any lymph-node (oil-immersion lens!), the inter- pretation of the histological appearances is always difficult, and liable to vary with different observers. It is not easy to decide whether the cells present are really the result of cytoplasia of hsemopoietic cells, and are not produced by multiplication of indifferent or non-haemopoietic tissue-elements (i.e., a productive " inflammatory " process, with subsequent pressure atrophy of the specific parenchymal cells). The classical references to metaplasias of the pulp tissues in the spleen or lymph-node nevertheless show that there is a consensus of opinion among those who Icnow best, to the effect that cjrtoplastic changes may actually take place, and that an interpretation in a phlogoblastic direction is not always justified. We should therefore conclude that in some of the so- caUed blood diseases, the tissue-changes partake of the character of local intracellular metamorphoses. In the second place, it is necessary to distinguish between metaplasias and degenerative processes. It is evident that a pre- ponderance of plasma ceUs in a lymphadenoid tissue, e.g., must be the result either of infiltration by extraneous cells, or of degeneration of existing cells, or, lastly, of a tendency, abnormal it is true, to develop along that line. If the change into a plasma cell is to be looked on as a degeneration, then the whole process must be described as degenerative and not metaplastic. But we have already seen that the conversion of lymphoid into plasma cells is not the whole story, because these in their turn are apt to become fibroblastic in certain cases, a fact which stamps the process as not itself degenerative. In the third place, a metaplastic process may be simulated by a hyperplastic one. In the example just referred to, one might 19 290 Biology of the Blood-cells interpret a change of type from lymphocytoid to plasmoid as the effect of hyperplasia of plasma cells. On the other hand, this would imply that the mass of the plasma cells was not advancing in differentiation, and would always remain in the same phase of development. Secondly, it would imply that the plasma cell was a physiological inhabitant of the given tissue. The term hyper- plasia may, however, be applied correctly, if we interpret the process as one of excessive multiplication along accustomed lines, peopling the tissue with cell-units which are usually only present at all, as a response to substances whose character are at present unknown, sometimes found in apparently healthy tissues (normal catabolic processes), but usually abundant in certain pathological lesions. In the same way, the question of anaplastic versus metaplastic or phlogoblastic changes largely depends on the view-point adopted about the individual cells. Those who see a retrograde process in the formation of plasma-cell accumulations would call the tissue change anaplastic, but the almost regular presence of amitosis in such inflammatory areas as are in mind, seem to contraindicate the theory of retrogression. There remains only one other possibility, that the cells present in the tissue are merely transported cells. Are plasma cells and eosinophiles carried thither, or are they formed on the spot ? This has been the burning question, especially in the case of the so-called myeloid metaplasia. There can be little doubt that both events take place in the latter instance. The blood of such cases may contain isolated myelocytes which possess the power of locomotion, and may easily congregate in the special regions where myeloid meta- plasia is met with. On the other hand, there is definite evidence in favour of the view that many myelocytic cells actually form from parental parenchymal cells pre-existent in the tissues. We have discussed these points seriatim, as the whole argument would necessarily be obscured in an attempt to show that there is no hard-and-fast line of distinction between any of the processes named, and that we may easily encounter combinations between them. If metaplasia be associated with hyperplasia we should speak of a metahyperplastic process without attempting to define Metaplasia in General 291 where the one ends and the other begins. There is no reason why a cell may not undergo anaplasia (descent in the scale of phylo- genetic differentiation, at the same time as the cell ages*) and then re-awaken and pursue another path of phylogenetic development. The most ardent and thorough exposition of the principles laid down above we owe to the labours of Pappenheim^ in the first instance, and the intricacies of his arguments dependent on cyto- Iqgical dye-reactions and other considerations afford a very con- vincing proof of his thesis, although the complexity of the termin- ology adopted by him renders the study of his contributions in the " Folia Hsematologica " rather toUsome. Other workers, well-known in the field of hsematology, have joined in the demonstration of the labile and protean character of the cell-constituents, principally of the pulpar tissues ; of the changes in type of development arising under noxious bacterial influences. We may further instance the observations of Tomaszewski,^ Miiller,* Marchand,^ Liidke,® Vos- winckel and Dunzelt,7 in reference to the production of hyperplastic processes in special cell-groups in the different forms of leukaemia ; the work of Kellings and Litten^ on the inter-relation between leuksemic changes and the myelotoxicoses of clinically pernicious anaemia ; the investigation of Amspergeri" on endemic leuksemic manifestations. Pappenheimn has pointed out the difference between the action of a phanerogenetic infection on the blood- forming tissues, and that of a cryptogenetic infection. The former sets up a pure metaplasia, the latter sets up hyperplasia in addition. The importance of this distinction lies in the fact that specific cell proliferation may be set up regardless of inborn tendencies on the part of the cells affected, because it leads to the conclusion that cytoplastic processes may be artificially induced. The converse may be reasonably expected, and curative treatment hoped for. The pure hyperplasia may be an inevitable result of the obscure infections, but the metaplastic change (as in leukaemic diseases, and in malignant granulomatosis)! depend entirely upon an exogenic agent, whether that be organismal or of the nature of an intoxication. * The question of time complicates tlie description of these phenomena. It is more convenient to ignore it as a merely relative idea, t One of the forms of Hodglcin's disease. 292 Biology of the Blood-cells Duval demonstrated an ability to produce a lesion analogous to the crytogenetic granulomatosis of Hodgkin's disease by the exhi- bition to a guinea-pig of an attenuated mallein. Podwyssozkii2 showed that talc injected intraperitoneally, produces nodules in the mesentery and peritoneum, rich in giant cells derived from the perithelial and adventitial cells, and forms a granuloma. He argued that here a substance acting mechanically (because it could not be digested), and not toxicaUy, would produce a strong formative stimulus on the cell nuclei and set up nuclear proliferation. Expressed in symbolic form, these different morbid lesions may be gathered together by taking cognizance of : A, the predisposition to develop neoplasms ; B, the predisposition to autonomous and unlimited proliferation common to all cells ; C, C, C", C", different stimuli to hyperplasia. In the case of malignant granuloma,* the addition of A and C leads to B. In the case of leukaemia, the addition of A and C leads to B. In the case of pseudoleuksemias, the addition of A and C" produces B. Chronic inflammatory processes, again, under the influence of A and C", will sometimes end in B, manifested in the formation of some neoplasm. The various processes designated by the letter B are also labelled variants or types of lymphosarcoma by the clinical or the surgical pathologist. One single noxa, one form of atom- group, or, as we shall see presently, some stereochemical position,* may be the ultimate reason for the different manifestations, work- ing as it would upon a variable material. At first sight it appears impossible that so many diverse tissue masses should be produced in a seemingly simple group of lymphoid cells. A little reflection will, however, show that in the haemo- poietic tissue, as in the solid portions of bone, we are dealing with a connective-tissue cell with multiple potentialities. If one such cell can secrete bone at one time, cartilage at another, fibrous tissue at another, there is no reason why the mesenchymal cell should not * Of. " conditions " of an experiment. Metaplasia in General 293 at one time develop myelo- at another lympho-potentialities. Once accept the view that the adventitial cell can withdraw its hold from a capillary, acquire powers of locomotion, and appear as a Saxer wandering ceU, and there is no difficulty in believing that different extraneous influences, different pabulum, and so forth, may lead to varying products of proliferation. In a sense this would be described as endowment of the mesenchymal cell with embryonic characters, but the word embryonic is apt to be mis- leading. The formation of a polyblast (Maximow), of the parent of small-round-celled infiltration, of mast cells, of plasma cells of various forms (Krompecheri^), of fibroblasts (Borst), or of epithelioid cells (Marschalko, Krompecher, Schottlander), and so on, is only on a par with the ability of indifferent connective-tissue cells taking on mucoid, chondroid, osseous, or any other allied character.* In the lymphadenoid tissue we have indifferent cells which usually run along a definite line of development, culminating in cells habitual to the blood-stream. Under abnormal stimiali they may be expected to enter on unusual lines of development, and even exhibit some of the metaplastoid or neoplastoid tendencies associated with subacute and chronic inflammatory processes else- where in the body. The key-note for the study of these changes, then, remains this : that the cell-individual itself must be investigated. When the mechanism and causes of metaplasia in a cell are understood, the gross effect of the tissue mass as a whole is readily understood, being, as it is, the outcome of cytoplastic change occurring simul- taneously in a number of cell -individuals of the same order. More than this, a given agent may set up changes, not merely in one order of cells, but may act on several varieties simultEineously. It may, for instance, act not only on the parenchymal cells, but also on the stromatic cells of the pulpar tissue.f 2. — The Mechanism of Metaplasia. When referring to the chemical questions arising in connection * It will be remembered that the indifferent connective-tissue cells of bone are stromatic, and not parenchymal. t Refer also to Section III. of Chapter I. 294 Biology of the Blood-cells with cell metabolism, the interaction between nuclear matter and spongio- or hyaloplasm was discussed. The most striking example of the kind was exhibited by the red cell during its conversion from a nucleated hsemoblast to a non-nucleated hsemoglobin-rich erythroc5rte. The steady oozing of the parachromatin (probably in an altered form) into the paraplasm, brings it in contact with amino- groups and leads to the synthesis of haemoglobin. Speaking in general terms, the chemical basis of metaplasia might be regarded as a conversion of paraplasm and parachromatin from basophilia to oxyphilia, plus loss of spongioplasm.i* The nuclear precedes the cytoplasmic differentiation in point of time.i^ If we deal with cells as if they were organic chemical compounds, we find ourselves able to draw some analogies between metaplastic processes as discussed above, and certain interactions met with in organic chemistry. Before doing so, however, it must be pointed out that the analogies are merely suggested, are not capable of logical proof, and must be associated with other factors (surface tension, etc.) ; for this reason they will only be given briefly. Certain substances endowed with stereochemical attributes are comparable with cells in process of metaplasia, because each may possess a given outward form (molecular formula : special morphology) under which are variants differing from one another in internal structural arrangements (structural or spacial formula : morphology of variants). Simple chemical agencies may bring about rearrangement of the atom-groups in one direction, or back to the original position (reversible reaction). We might label such processes as metaplastic, or anaplastic. Thus, the following simple example will suffice to indicate what is meant : Starting with ethyl nitrate and hydroxylamine, an interaction is possible with benz- aldehyde. The product is benzaldoxime, a body which exists in three stereo -isomeric forms. The y-compound passes into the a-compound under the influence of an ethereal solution of hydrochloric acid. The second isomer is convertible by the action of heat into the /3-oxime. The structural formula is the same in each, but the spacial one is different, as the atom-groups occupy different positions with respect to each other. This is an extreme example of a metaplastic process, in which the final product is only differen- Metaplasia in General 295 tiable by very subtle methods, just as the change from an indifferent pulpar cell into a leucoblastic cell is at first sight hypothetical. Each of the oximes may undergo a further and still more definitely metaplastic change by a process called Beckmann's substitution. The y-compound furnishes benzoyl phenyl urea, the a-compound becomes dibenzenylazoxime, and the /3-compound gives rise to oxanilid. This series of metamorphoses is very striking, because y-OxiME » Walker. Proc. Roy. Soc. B. Lxxviii. 1906. " Bunting. J. H. H. B., 1910. 12 Gruner. J. C. M. A. 1912, July. 13 Kolliker. Hdbch. d. Gewebelehre, Leipzig, 1889, vol. i. '* Sanfelice. Quoted by ref. 15. 15 Heidenhain. Plasma u. Zelle, 11, Jena, 1911. I' Ebner. Quoted by ref. 15. " Pappenheim. V. A. 1898, Bd. 151, p. 89. " FoA. Z. B. 1899. p. 376. 19 Werigo and Jaguinow. Pfliig. Arch. 1901, p. 457. 324 Biology of the Blood-cells '" LiFSCHiTZ. I. D. Ziirich, 1906. "1 Wright. Boston M. & S. Journal, 1906, p. 643. " Bunting. J. E. M. 1909 ; J- H. H. B. 1911, pp. 114, 369 ; Ogata. Z. B. 52. H. I. (1912). "3 Sternberg. In Krehl and Marchand (ref. 7, Chapter i) . 2« CiACCio. Quoted by Downey, F. H. ix. i. 81. "5 BizzozERO AND ToRRo. Moleschott's Untersuchungen, xi. 1881. 26DENYS. La Cellule, t. iv. 1888 ; Isaac and Mockel. Z. f. kl. M. 72, p. 3 14. " Maximow. a. f. m. A. Ixxxiii., 1909. "^ ScHAFER. In Quain's Anatomy, Vol. II, Part i. 1912. 29 His. Untersucli, 1868. 3" Maximow. A. 1 m. A. 76, H. i. 31 Engel. D. 1906. 29 ; Saxer, Anat. Hefte, 1896, vi ; Mollier, A. f. m. A. 74 ; Askanazy, V.A. 205, 3 ; Lobenhoffer, Z. B. 1908, Bd. 43 ; Kostanechi, Anat. Hefte, i8gi. i; Goodall, J. P. B. 1903, p. 191 ; T. H. Bryce, Quain's Anatomy, Vol. ii. Part i. p. 237 ; Pappenheim, quoted by Hirschfeld, F. H. vi. p. 388. 32 Grawitz. Klin. Path, des Blutes, Thieme, Leipzig, 1911. Taf. iii. 33 Grawitz. Ibid. p. 160. 3* Thayer. A. I. M. 1911, p. 223. 3' Sapegno. Pathologica, 1910, No. 33. 3° Schilling. M. 1911, p. 447. 3' Dietrich. B. H. G. Jan. 1910, ref. F. H. ix. 2, p. 170. 33 LoELE. . M. 1910, no. 46. *3» Schilling. Ref. 36 ; The latest and most fundamental article is F. H. xiv. i, pp. 96-244 (1912), with full literature upon the red blood cell. ^"Pappenheim. Atlas, Supplbd. p. 221; see ref. 37, Chapter i. 40a Freytag. Z. f. c Phys. Bd. vii. H. i ; Pappenheim's comment. F. 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I02, H. 5. 6. 166 DoNZELLO. Lo Sperimentale, 1906, 15. 16' Pappenheim. Comment on Krehl, Pathologische Physiologie, F. H. x. 2, p. bo (1911). 1'° Krehl. Pathologische Physiologie. F. C. W. Vogel, Leipzig, 1910. I'l Grawitz. Med. Record, 1910, Oct. 29. 1'" HiRSCHFELD. B. H. G., Oct. 10, 1911, ref. F. H., xii. 2, p. 235. 1" Gibelli. Arch. f. exp. P. Bd. 65, 3 4. 1'* Kapinow. B. Z. 30, p. 160. References to the Literature 327 1" Kramer. W. K. W. 1908, 34. "' Senator. Polyzythsemie v. Plethora, Hirschwald, Berlin, 191 1. 1" Pappenheim. Footnote commenting on Rubinstein (Russki Wratsch, 190S, 7, 8, in F. H. X. 2., p. 205.) Luce. Med. Klinik., 1909, 4, 5. ^" Rubinstein. Russki Wratsch 1908, 7, 8, 9. Good resumes on Pernicious Anaemia: Friedstein, xii. i, p. 239: Pappenheim Prolegomena, F. H. x. 2, p. 217; * B. H. G., 1911 (4 sessions), ref. F. H. xi. 2, p. 311, sqq. CHAPTER III. ' Weidenreich. Verhdl. d. anat. Gesell. Wiirzburg, 1907 (ref. F. H. v. 34) ; VerhdI. d. Berl. Haematol. Gesellschaft, March 5, 191 1 (ref. F. H. xi. 2. p. 22). ^ Ribbert. V. A. 150 (1897). ' Hedinger. F. Z. Bd. I., Nr. 3, 4. * Oehme. M. 1909, p. 446. ' Pappenheim. F. H. iv. Suppltbd. p. 297. ' Flemming. A. f. m. A. xxiv., 1885. ' Bunting. J. Anat. and Phys. xxxix., 1904-5. ' Baum and Halle. Anat. Anz. xxxii., 1908. " Naegeli. Blutkrankheiten und Blutdiagnostik, Leipzig, 1908. 1" PiRONE. Lo Sperimentale, jeuillet, 1907. 1' Keuthe. D., 1907, 15. 1' Schmidt, M. B. Z. f. allg. Path (Path.) 1907, xviii. 15. •^ CiACCio. F. H. viii. p. 135 (p. 151), 1909; CiAccio et Pizzini. A. de Med., Tome xvii. mars, 1905, p. 129. 1* Stheemann. Z. B. xlviii. i. 1* RuBENS-DuvAL ET Fage. Societe de Biologie, 1909, t. bcviii, 39, p. 696. "Metchnikoff and Tarassevitsch. Ann. de I'lnst. Past. 1902, xvi. p. 127. "MacLachlan. Tonsilhtis, a Histopathological Study, Publications from the University of Pittsburg, 1912. 18 Hertz. F. H. xiii. i, Tafel V. (1912). i» Andrews, F. W. Tr. Path. Soc. Lond., 1902, p. 305. 2" LoELE. C. xxii. 10, 1911. " Pascheff. M., 1911, p. 1937. '^ Marcuse. v. a. 160 (1900). 23 V. Wendt. F. Z. viii. 3, 19 11. 24 Hesse Thaysen. Z. B. 50, 3. 25 Schridde. In Lubarsch and Ostertag, Ergebnisse, ix. 2, p. 313 seq. 2« Borka. V. A. 205, 1-3 ; See Quain's Anatomy, Vol. i.. Embryology. 2'Maximow. V. d. anatom. Gesell. Brussels, 1910, p. 64. 2' Gruner. Studies in Puncture Fluids, H. K. Lewis, London, 1908. 2» Grawitz. Klin. Pathologie des Blutes, Georg Thieme, Leipzig, 1911, p. 201; see alsoJRASKiN, Marie, F. H. ix. i, p. 123 (1910), and Bergel, M. 1912, p. 634. '" Kallmark. F. H. xi. I, p. 411. " Caro. B. 1908, p. 1755. '" Galambos. F. H. xiii. i, 152 {with full literature). '' Rous. J. Exp. M., 1908, x., p. 329. ^* Harvey. J. Phys. Dec, 1906. '5 Bergel. M. 1912, p. 636. ^' LoEB AND MiCHAUD. B. Z., iii., p. 31, 317 ; LOEB, A. f. e. P. 1907. 56, p. 320. " Baldoni. Arch, di farmac. sperim. e scienze af&ni. 1905, p. 93 ; OppenheimeR; Handbuch der Biochemie, Bd. ii. 2, p. 171. " Erdely, quoted in Grawitz^', p. 271. 3' Goodall, Gulland and Paton. J. Phys. xxx., 1903. " Crescenzi. Lo Sperimentale, 1904 ; ^o^Burian and Schur., W. K. W. 1897, 6. " Pappenheim. F. H. vii. p. 167, footnote (1909). *2 Tschistowitsch. D., 1907, 13. 328 Biology of the Blood-cells *'Gerhartz, in Oppenheimer, Handbuch,^' p. Ii6. " CoHNHEiM, in Nagel, Handbuch der Physiologie, Bd. ii., p. 598, F. Vieweg und Sohn, Braunschweig, 1907. *^ FiscHEL. M., 1910, p. 1203. ■" Bergel. M., 1902, 2 ; 1910, 32. *' MiCHAELIS UND WOLFF-ElSNER. V. A. 167, 1902. *' *CiACCio, Fol. Clin. Chim. Microscop., Bd. ii., p. 224. ■" Pappenheim. F. H. ix. i, p. 321 (1910). *' Jagic. B. 1909, 26. *° Pappenheim und Ferrata. TJeber die verschiedenen lymphoiden Zellformen, etc., F. H. X. I, p. 78 (1910), published as a monograph in 1911, p. 76. '1 Klein. C, 1910, Bd. xxi., p. 677 ; Berl. Haemat. Gesell., May 3, 1910 (ref. F. H. ix. 2, p. 407). ^' Meves._ a. f. m. A., Ixxv. p. 642 (1910) ; Freidsohn. A. f. m. A., Ixxv., 1910. ^' Sabrazes et Muratet. F. H. vi. p. 167 (1908). "Downey. F. H., viii. p. 415 (1909). "' Fry. F. H. viii. p. 467 (1909). 5' Drzewina. a. d'anat. mic. 1910, xii. i, i. ^' Werzberg. F. H. xi. i. p. 17. ** Kasarinoff. F. H. x. I, p. 391 (1910). '9 Davis and Carlsson. Am. J. PJiys., 1909, xxv. '"Rosenthal. F. H., x. i, p. 278 {1910). "■ Selling. Z. B., 51, 3. "2 HoFMEisTER A. f. e. P. 1887, xxii. "^ Hammar. Anat. Anz. 1905, Bd. xxvii. ** Penny. B. M. J., 1909, June 12. '5 Proscher. F. H., vii. p. 107 (1909). " Bartel. Vers. deut. Naturforscheru. Artze, Salzburg, 1907 ; ref. F. H. x. 2, p. 109. " Kormoczi. Krankenvorstellung im Vereiu der Spitalarzte zu Budapest, May 4, 1910, ref. F. H. xi. 2, p. 297. PoHL. Arch. f. e. P. 1889, xxv. p. 51. , Jolly. C. R. de Tassoc. des anatomistes, 13 reunion, Paris, 1911, p. 164. LABsfe. La Presse Medicale, 1908, No. 97, p. 786. CHAPTER IV. The following references may be quoted as supplying very full information about the subject of this chapter : — Pappenheim, xii. 2, p. 382-411 ; B. H. G. xi. 2, p. 224. Monograph, ref. 50. Chapter iii. 1 Mangubi-Kudrjavtzewa, Anna. Inaug.-Dissert. Giessen, 1909 ; Anat. Hefte, 1900, p. 699. ^ Mollier. a. f. m. A., Bd. Ixxvi. ' Perlmeschko. Quoted by Pappenheim, editorial note to ref. No. 4^ F H vii p. 68. ^ ■ ■ ^Kalatschnikoff. Russki Wratsch, 1907, 27. Asai. Tokio Igakkai, 1908, 16. ' CiAccio and Pizzini. a. de Med., Tome xvii., mars, 1905, p. 129. ' PiRONE. Lo Sperimentale, jeuillet, 1907. ' CiAccio. V. A. Bd. 199, H. 2, 3. 8 LoELE. F. H. xiv. I, 38 ; F. H. xui., p. 331 and references ; C. B. 1911, xxii. 10 ; F. Z . ix. 3, p. 436 ; F. H. xi. 2, pp. 45-48. ' Siegfried. E. d. Phys. 1910, ix. p. 334. " Blumenthal. Bull. Acad. med. Belgique, 1904 ; Bull, de Soc. royale des sc. med. et nat. de Bruxelles, 1908, i. '1 Gross. Quoted by Kohlenberger, 1\I. igii, p. 2013. ^' Herzen. Quoted by Ciaccio, A. de Med. 1905, p. 129. References to the Literature 329 '' Pauliczek. F. H. ix.. i, p. 475 (1910). AzzuRiNi. Lo Sperimentale, 1906, vol. iv. fasc. 4. " AsHER. D. loii, p. 1310. ^^ Grossenbacher and Zimmermann. B. Z. xvii., pp. 7S, 297. ^' SzoKALSKi. Medycyne, 1908, No. 16. ^' JuNGANO. II Tommasi, 1906, No. 16. 1* AzzuRiNi. Lo Sperimentale, 1906, vol. iv., fasc. 4 ; Jarotzky, V. A. (1908), 191. ^' ScoTTi. Gazz. Internazionale, 1910, p. 51. ^^ Bergel. M. 1912, p. 635. " Braunstein. B. 1911, No. 45; M. 1911, p. 2465 ; "^Oser and Pribram, Z. e. P. 12, 2, ref. M., 1913, p. 770. '"^ PopiELSKi. M. 1912, p. 554. =" DiNKLER. M. I9II, p. I33I. ^* Winkler. Charkowski Medizinski, 1907. 25 Faltin. D. Z. Cliir. 1911, No. 1-3. 26 LiTTEN. Nothnagel's Handbuch, Krankheiten der Milz, 189S, p. 16. ^' Tizzoni, Mosler. Quoted by Paremusoff, F. H. xii. i, p. 234. 2' Faltin. M. 1911, p. 1738 (D. Z. Chir. no, 1-3). ^' Radford. J. Anat. and Phys. 1908, p. 288. ■^" FoURGEOT. C. R. de 1' Assoc, des anatomistes, iie reunion, Nancy, 1909, p. 133. ^1 Vincent and Harrison. Quoted in Quain's Anatomy, Vol. ii.. Part i., 1912. ^' Quain's Anatomy, Vol. ii.. Part i, 1912. ^3 Warthin. Meeting of Am. Assoc. Path, and Bacteriologists, Chicago, igii. ^' Lewis. Proc. Physiol. Soc, March, 1912. •''■ WOLTMANN. J. E. M., 1905. ^' Houston. B. M. J., 1904, Sept. 10. ^' Com. ThSse de Lyon, 1911. ^* Sapegus. Pathologica, 1910, No. 33. ^' Spadaro. Mononukleosi, endotehosi, linfocitosi, Verlag Fronusco Vallardi, Milano, 1908 ; ref. F. H. v. p. 454 (out of print, 1912). ^'' Grawitz. Klin. Pathologie des Blutes, Thieme. Leipzig, 1911, p. 206. ■*' KuRLOFF. Ehrlich, Anamie, Bd. i. p. 57. ■*2 Pappenhbim. F. H. v. p. 347 (364), 1908. -■^ Patella. F. H. v. p. 195 (1908). *" Patella. La genese endotheliale des leucocytes mononucleaires du sang. Siena, 191 o. -*5 Patella. Riforma Medica, 1907, No. 8-9. *' Cesaris Demel. Lo Sperimentale, 1905, vol. 59. " Cicacio. See ref. 7. ^' Gruneberg. Medizinisch-Naturwissenschaftliches Archiv, 1908, vol. i.. No. 3. ■*' Grawitz. See ref. 40. ^'' Pappenheim and Ferrata. See ref. 50, Chapter III. ■5' Spadaro. See ref. 39. °^ Paremusoff. F. H. xii. i, p. 236, and Taf. xi, Nos. 1-8. ■5' Jagic. B., 1909, No. 26. 5* Patella. D. 1910, 32; F. H. vii. p. 218 (full details) ; full discussion, Frvimldn, F. H. xii., I, 50 (1911). ^^ Patella. La genesi endotheliale dei leucociti mononucleati, etc., edit. S. Bernardino ; ref. F. H. v. 786. "= Patella. F. H, vii. p. 219. " Patella. Gaz. degl. Osped., 191 1, p. 94. ■'' Ferrata. Arch, per le scienze mediche, 1906, t. xxx. •" Carpi. Auto-riassunti, vol. v. No. 5. •"> Frumkin. F. H. xii. i, p. 50 (1911). ■»i Metchnikoff. L'Immunit6 dans les maladies infectieuses. Paris, 1901. "2 Bergel. M., 1912, p. 635. *°^ RiEUX. F. H. x., I, p. 209. ** Penny. B. M. J. June 12, 1909. ''5 ScHlFONE. Prima contribuzione alia genesi dei mononucleari del .sangue. Napoli, 1907 ; ref. F. H. ix. 2, p. 17^ 330 Biology of the Blood-cells '^* Pappenheim. F. H. ix., i, p. 560. " Hynek. Berl. Hjem. Gesell. March 5, 1911, ref. F. H. xi. 2, p. 224. " CiAccio. See ref. ^T; Chapter III. «* Bruntz. C. R. de la Soc. de Biol. t. Ix. p. 831. " PoLiCARD ET Mawas. C. R. de 1' Assoc, des Anat., ge reunion, Lille, 1907, p. 25. '" Mestral. Trav. Instit. path, de Lausanne, 1907, vol. iv. " Maximow. Ref. 27, Chapter III. '* Jolly. Soc. de Biol. 191 1, p. 259. "Werzberg. F. H. xi. I, p. 17. '* HiRSCHFELD-KossMANN. Beitrag z. vergleich. Morphol. d. weissen Blutkorperchen, Inaug. Dissert, Berlin, 1908. " Kasarinoff. F. H. X. I, p. 391. '« Paremusoff. F. H. xii. i, p. 195. " LiFSCHiTZ. I. D. Zurich, 1906. CHAPTER V. 1 Quoted by Maximow. Z. B., 1907, Bd. xli. H. i. * ^ Carnegie Dickson. The Bone-Marrow, A Cytological Study. Longmans, Green & Co., London, 1908. ' Walker, C. E. Proc. Roy. Soc. Ixxix. 1907 (Observations on the Life History of Leucocytes, iii.). * Ciaccio. F. H. vii. p. 321 (1909). ^ Cruikshank. J. P. B., 1911, p. 167. ' Gruner. J. C. M. A. July, 1912. ' LuciBELLi. Riforma Medica, 1909, 2. ' LoNGCOPE. Bull. Ayer Clin. Lab., 1907, No. 4, p. 6. • Ciaccio. Same as ref. 4. '" Minkowski. E. Bd. vii. p. 39. '' PiRONE. Lo Sperimentale, 1907; Fasc. i, 2, p. 83 ; and refs. in F. H. vii. pp. 67-71. " AuBERTiN AND Beaujard. F. H. vi., p. 31 (1908). BiLAMlONi. Lo Speri- mentale, 1906. ^' Pappenheim. F. H. v. p. 341, igoS. '* Helly. Verh. d. deutsch. Path. Gesell. 1910, p. 198. 1' Ciaccio. F. H. vii. p. 321 (igog), and see Schridde, M., 1906, p. 1885. "TsuNOTA. V. A. 202, H. I. 1' LossEN. M., 1907, 39. '' Dantschakoff, Wera. Verhandl. d. anat. Gesell. April, igo8. " Helly. Z. B., igo5, 2. "" Schridde. See ref. 35, to Chapter I. *' RiBBERT, MUIR, DOMINICI. 22 Blumenthal. Bull, de Soc. royale d. Sciences med. et nat. de Bruxelles, igo8. No. I. ^' Jagic. B. 1909, 26. "* Blumenthal. F. H. vii. p. 297 (igog). ?' Errera. Recueil de I'lnstitut botanique, igo8, Bruxelles, t. vii. 2° Heidenhain. a. f. m. A. xhii. i8g4. "' Neumann. V. A. 143, 174, p. 41. ^* Brugsch and Schilling. F. H. vi., p. 322 (igo8). 28 Deetjen. Quoted by ref. 28. " Arneth. D., 1904, 2, 3, and a number of papers given in extenso by Schilling- Torgau, F. H. xii. i, pp. 130 sqq. *'i Schilling. F. H. xii. i, 130 (igii). ^2 Russo. Soc. Med. des hop. de Lyon, 31 mai, igio. 3' Pappenheim. B. H. G. Jan. 11, igio, ref. F. H. ix. 2, p. 172. " Schilling. F. H. vi., p. 429 {1908). ^' Schafer. Quain's Anatomy, ref. 32 to Chapter IV. References to the Literature 331 3» PoLLiTZER. Z. f. H., 1907, Bd. 28, H. 10. ^' Weidenreich. a. f. m. A., Ixxii, p. 209. '' MiCHAELis. Berl. Haem. Gesell., 1909, ref. F. H. vii. p. 81. " Pappenheim and others, same ref. as 38. *" Massart et Bordet. Soc. royale des Sciences med. et nat. de Bruxelles, Feb. 1890. *' MiLKOWiTscH. Russki Wratsch, 191 1, 22. '^ ACHARD AND Ramond. C. R. t. Ixxi., No. 27, p. 260. " Winkler. F. H. ix. i, p. 94 (1910). ** LoEB. Same ref. as 38. *' GULLAND. J. Phys., xix. " Decastello and Krjukoff. Untersuchungen uber die Struktur der Blutzellen. Urban and Schwarzenberg, 191 1. •' MiJHLMANN. B. 1907, No. 8. *^ Downey. F. H., vii., p. 415 (1909). " LoEW and Bokorny. Die chemische Energie der lebenden Zellen. Stuttgart, 1906. ''' Schneider. M., 1908, p. 499. '1 Oxner. Bull, de I'lnst. Ocaenograph. Monaco, 1908 ; Kollmann, C. R. t. bcxi.. No. 27, p. 262. " LowiT. E. 1900, p. 36. 63 Drzewina. Soc. de Biol. 1908, t. Ixiv. p. 1039. " Fry. F. H. viii., p. 499. " CiACCio. See ref. 47* to Chapter III. " Marino. Ann. Past. 1903, p. 357. " Bogdanoff. B. Z., 1898, H. viii. " Sabrazes et Muratet. F. H. vii. p. 171, 1908. " Arnold. V. A., 159, p. loi. •0 ScHWARZ. W. K. W. 1901, 42. " Pappenheim. V. A. 151, 1898, p. 134, and criticism of Lefas, ref. F. H., vi. p. 70. '^ Commessatii. Rivist. critic, di clinica med. 1907, No. 47, 48. ^' Brown, W. H. Practitioner, Jan., 1910; see also refs. F. H. ix. 2, pp. 131-135, on iodophiha. '* Da Costa. Therapeutic Gazette, Oct. 5, 1906. »' Pappenheim. F. H. ix. i, p. 321 (370). ^' Abetti. II Policlinico, 1910, No. 8. " WosKRESSENSKi. Russ. med. Rundschau, 1907, No. 12. " Neukerich. Z. f. kl. Med. Bd. Ixx. 3, 4. " ClACCio. See ref. 55, and Fol. clin. chim. e microscop. 1910, p. 224. '" Gardella. La Ginecologia, 1909. '1 ToussET ET Troisier. Soc. de Biol., 1907, p. 104. "> Martelli. Pathologica, 1909, No. 23. " Leber. Die Enstehung der Entzundung, Leipzig, 1891. '" Erben. Z. f. H. 24 ; Z. f. kl. Med. 40 ; Hofmann's Beitr. 5. '* MiJLLER and Jochmann. M. 1906, Nos. 29, 31, 41, 43. "WiENS. E., 1911, I5te Jahrgang, i abt. " Meisner. Z. f. H., vol. 72, 1912 ; see also Proc. Roy. Soc. Med., Dec. 1912, on anti-diphtheritic serum and iodine. " Jochmann. V. A., 194, p. 342. '» Pappenheim. Atlas (ref. 12, Chapter I.), Suppltbd. p. 84. "> Cesaris-Demel. R. Academia di Med. di Torino, 1906 ; Arch, per la scienze mediche, 1905, t. xxix. " Kaplan. F. H., vii., p. 97 (1909)- 82 Weidenreich. A. f. m. A. Bd. Ixxii. p. 209. *3 Helly. Z. B., 1905, xxxvii, 2. *" Cesaris-Demel. V. A., 1909, 195, i ; see also F. H. viii., p. 155 (1909). *^ CiACCio. Same ref. as 47*, Chapter III. *° QuARELLi AND BoTTiNO. Giomo dell. R. Acad. d. Med. d. Torino, 1907. 8' Hardy. J. Phys., 1892. 332 Biology of the Blood-cells 8» Fry. F. H. viii., Plate 8, Fig. 2. *» KoLLMANN. Soc. de Biol. 1907, p. 226 ; Ann. deSci. Nat. Zool. 1908, t. viii, i, 4. <"> Bruntz. C. R. de la Soc. de Biol. vol. Ix. p. 835. »» Fry. F. H. viii., p. 472 (1909)- '2 Sabrazes et Muratet. F. H. vii. p. 171, 1908. " Downey. F. H. viii., p. 432. " Stephan. C. R., t. Ixi., p. 501. '"' Gruneberg. V. A., 1901, Bd. 163. "» HiRSCHFELD. B. H. G. Jan. 11, 1910 ; ref. F. H, ix. 2, p. 171. " Sabrazes, Muratet et Durrouz. Gaz. hebd. des Soc. med. de Bordeaux, 1908, p. 325 sqq. " Kasarinoff. F. H. X. I, p. 391-1910. '" ScHiFONE. Contributo alia morfologia comparata dei leucociti nei vertebrati. I. Mammiferi et Uccelli ; Napoli, Michele d'Auria, Tribunali 386, 1907 ; and Pappenheim, Z. f. klin. Med. 43, and V. A. 1899, Bd. 157, p. 74. 100 FuRNO. F. H. xi. I, p. 219, 1911. i(n Wernstedt. Nordisch. med. Archiv f. inn. Med. 1910, Abt. ii., H. 3. 1»2 DUNGKR. D. A. xci., 3, 4. '"' MiRANO. La riforma medica, 1907, 23. "* Keuthe. X>. 1907, 15. ">s Lepine and Popoff. Soc. de Biol., 1907, t. Ixiii., p. 364. i»« MiLKOWiTSCH. Russki Wratsch, 1911, No. 22. "' Gautier. Soc. de Biol., 1907, t. Ixii. p. 88. "" Krause. 3 Kongress der Deutsch. Rontgengesellschaft, 1907, ref. F. H. v. 450. 1™ Pappenheim. Grundriss d. haematolog. diagnostik u. praktischen Blutunter- suchung, Werner Kinkhardt, Leipzig, 191 1. '1° Manuchin. Russki Wratsch, 1910, Bd. ix. H. 11. "1 Selling. Z. B., 51, 3. "' Falte, Kriser, Zehner. M., 1912, p. 734. "' Magi. Arch, di Farmacol., 1908, 3. ^" Ross. Further Researches on Induced Cell Proliferation London, 1912 ; see also B. M. J. Jan. 23, 1909, p. 33, Lancet 1909, Jan. 30 ; Literature given here. "^ Zoja. F. H., x. I, p. 239 (1910). CHAPTER VI. ' Pappenheim. F. H. xi. 2, p. 129. ' Arneth. D. a., Bd. xcix. ' Roth. D. A., cii., H. 5, 6. * Arnold. V. A. 1907, cxc. i ; M. 1907, p. 2441 ; Pirone, Lo Sperimentale, 1907, Fasc V. ' LoELE. C. Path., 1911. * WiENS-ScHLECHT. Quoted by Pappenheim, remarks to ref. Kreibich, F. H. ix. 2, p. 390- ' Weiss. Haematologische Untersuchungen, 1896. Wien and Leipzig, Carl Prohaska. * Nickel. Die Farbenreaktionen der Kohlenstofiverbindungen, 1890, Berlin, H. Peters ; see also Pappenheim, F. H. iv. p. 328 (1907). ' Petry. M. 1912, p. 1092 ; B. Z. 38, p. 92. 1° Marwedel. Beit. z. Path. Anat., 22, 507. ^^ Kreibich. W. K. W., 1910, 19. ^" Arnold. Z. f. a. P., xxi. i, and M. 1907, p. 2441 ; see also Berka, Z. f. a. P. xxi. 8. ^' Bennachio. F. H. xi. i, p. 253. ^* ScHWARZ. W. K. W. 1901, 42. 1= Stephan. C. R. 1906, t. Ixi. No. 34. ^° Reicher. B. H. G. Ap. 12, 1910 ; ref. in F. H. ix. 2, p. 397. " Rous. J. E. M. 1908, X. p. 537. ^ ' Pirone. Lo Sperimentale, 1907, fasc. v. " Weidenreich. V. d. D. P. G., 1903. References in the Literature 333 " Kammerer. M., 1907, 29. '^ aschenheim und tomono. "^ Pascheff. F. H. xi. I, p. 430. '^ WOLTMANN. J. E. M. 1905, pp. 119, 162. " Berka. Z. f. a. P. xxi. 8. '' Pappenheim. Quoted by Proscher, F. H. ii. p. 547 {1905). "' Howard, C. P. J. M. R. 1907, p. 237. " Sansonow. Dissert. St. Petersburg, 1908. ** Foster. J. M. R., 1908, p. 837. ^' Pascheff. F. H. xi. i, 460, and Plate X. =» Howard, C. J. M. R., 1907 (Dec). '^ Leighton. J. P. B. 191 1, p. 463. =^ Opie. Am. J. M. S. 1904, Feb. =' Weidenreich. a. f. m. A., 1908, 72. " Werzberg. F. H. xi. I, p. 17 (1911). "^ Arnold. V. A. 1899, Bd. 150. '° Kasarinoff. F. H. X. I, p. 391 (1910). Literature on Mast Cells, see F. H. xi. i, pp. 252 and 269; Sabrazes et Lafon, F. H. vi. p. 3 (1908). " MiCHAELIS AND WOLFF. M., I902, p. 227. '" Weidenreich. F. H. v. p. 135 sqq. Gives list of literature. "' Ehrlich. Verhdl. d. Physiol. Gesell. Berlin, 1878-9. " Berka. V. A., 205, 1-3. " Unna. a. f. m. A. 191 1, Bd. 78 (Waldeyer Festschrift). *^ CiACCio. Fol. Clin. Chim. Microscop. Bd. II. p. 224. " Meirowsky. F. H. vi. p. 42 (1908). ** Pappenheim. On methyl-green pyronin reaction, F. H. vi. p. 51 (6). *^ Pappenheim. F. H. ix. i, p. 576, 1910. *° Pappenheim. F. H. ix. i, p. 596. *' Harris. Phil. Med. Journal, April, 1910. ** Bennachio. F. H. xi. I, p. 253 {1911). " Schreibkr. M. 1902, p. 2075. '" Proscher. F. H. vii. p. 107 (1909). " Sabrazes et Lafon. F. H. vi. p. 3 {1908), and Plate II., and Arnold, M. 1906, 13. Good on Mast Cells : Pappenheim and Szecsi, F. H. xiii. i, p. 34. *52 Hertz. F. H. xiii. i, p. 177 (1912). " Brotz. Z. f. a. P., 1910, No. 14. '* Pappenheim. F. H. xiii. 2, p. 334 (Prolegomena) (1912). "^ Pappenheim. F. H. ix. i, p. 569 (footnote) (1910). ^'-Schridde. Z. B., 1907, Bd. 41 ; consult also "Die eitrigen Entziindungen des Eileiters," Gustav Fischer, Jena, 1910. Good on Plasma Cells : Pappenheim, F. H. xiii. 2, pp. i-O, p. 334, and F. H. xi. 2, pp. 170-17S, xl. I, p. 310. " Wallgren. Z. B., Bd. 51, H. 2. 5' Hofmann. M., 1904, No. 47. '» Pappenheim on Schridde in F. H. iv., Suppltbd. p. 283 (p. 295, foot), (1907). '0 Harris. See ref. 47. "■ Proell. Z. f. a. P. xxii. 9. " Schridde. C. xvi., 11, 1905. "' Maciesko-Jalenska. M., 1907, p. 1790. " Enderlen and Justi. D. Z. Bd. 62. '' Pappenheim. F. H. xii. 2, Prolegomena, p. 4. «« Wolf. F. Z. v. H. 2. «' Miller. V. A. cxc. p. 482 (1910). " Alegno. V. A. 204, 2. " Joannovics. C, 1909, Bd. xx. ; and Z. f. H. 1899, Bd. xx. '0 Downey. F. H. xi. i, p. 275 (1911)- " Schlesinger. V. A. 169, p. 428. " Goldmann. B. z. k.- Ch. 1989, No. 64, p. 192. 334 Biology of the Blood-cells CHAPTER VII. '■ Orth. Ueber Metaplasie, xvi. Congres I. M. 4 section. M. BoRST. Metaplasie, Aschoff's Path. Anatomie, 1911, i, p. 599- ScHRiDDE. Die ortsfremden Epithelgewebe des Menschen. Untersuchungen und Betrachtungen. Samml. Anat. u. phys. Vortrage u. Aufsatze. Gaupp u. Nagel. Jena, igog, Heft 6. G. M. Smith. J. M. R. 1913, p. 147 ; Benda, B. H. G., Nov. 7, 1911, ref. F. H. xii., 2, p. 249 ; also Pappenheim, F. H. iv. pp. 150-160, 350-360, 539-542- 2 Pappenheim. F. H. vii. Prolegomena; ix. i, p. 572; and innumerable other works. ' Tomaszewski. F. H. xii. i, p. 115. « MiJLLER. M. 1911, p. 713. ' Marchand. M. 191 1, p. 924. « LiJDKE. D. A. Bd. c. 5, 8. ' VOSWINCKEL U. DUNZELT. D. A. Bd. C. 5. » Kelling. M. 1906, p. 1901. ' LiTTEN. B. 1877. 1" Arnsperger. M. 1905. " Pappenheim und Hirschfeld. F. H. v. p. 347 (1908) (especially pp. 371, 390). 12 PoDWYssozKi. B. z. p. A. Bd. 47, H. 2. 1' Krompecher. Z. B. 1898. i* Pappenheim. F. H. ix, p. 574. >= Pappenheim. F. H. ix. i, p. 346. i« Gruner, Scrimger, and Foster. A. I. M., 1912, p. 641. 1' See ref. 11. 1' Paltauf. M. 1912, p. 214. 1' AsKANAZY. V. A. 205, p. 3. 20 Neumann. V. A. 207, H. 3 (1910), p. 379- 21 Hirschfeld. B. 1906, No. 32. " Hirschfeld. B. 1902, p. 701. 2' Schatiloff. Charkowskij Medizinsky, 1908, T. v. No. 3. ^^ Werzberg. V. A. 204, H. 2, 3. 25 AcHARD ET Weil. Arch, de med. exp. et d'anat. path. 1907, p. 319. 2° Jarotsky. Vortrag d. Dorpater Naturforschergesellschaft, May, 1911, ref. F. H. xii. 2, p. 327. " Selling. Z. B. Bd. 51, H. 3. '^ Sternberg. W. K. W. 1911, p. 1623 (also literature in this paper). 2' Pappenheim. Prolegomena, F. H. xii. 2, p. 285. '» Frankel in Ehrlich, Anaemia, Bd. I. 31 Ehrlich and Lazarus, Ehrlich and Pincus, Schridde, Ziegler, Helly, LowiT. 32 Askanazy. V. A. 205, H. 3 ; M. 1912, p. 38. 33 Schwarz and Michaelis. Z. f. H. Bd. 32, p. 294 ; Verhdl. d. Kongress f. inn. Med. 19th Congress, 1901, p. 273.^ =" Neumann. V. A. 207, H. 3. 33 Banti. Z. f. path. Anat. 1904, H. i. 33 Dominici. a. d. Med., 1901, i. 3' Hertz. F. H. xii. i, p. 40. 33 Pappenheim. Ref. No. 15 (p. 352 sqq.). 33 Hertz. Z. f. kl. M. Ixxi. 40 Werzberg. Same as ref. 24. " Paremusoff. F. H. xii. i, p. 195 (1911). On Myeloid Metaplasia. Fischer. Julius Springer, Berlin, 1909. For Theories on Myeloid Metaplasia, Pappenheim, F. H. iv. Suppltd., p. 336. *3 Pappenheim. F. H. v. p. 396 (1908). « Rubinstein. Z. f. kl. M. Bd. 61, H. 5, 6. " Hirschfeld. F. H. vii., p. 144, 1909. 43 Pappenheim. Same ref. as preceding, footnote. References to the Literature 335 *« Frank and Isaak. M. 1912, p. 491 ; Z. f. kl. Med., Bd. 74, H. i, 2. " V. Decastello. F. H. xiii. i, p. 471 (1912). *** Fabian. C. 191 i, with full literature. " KuNDRAT. W. K. W. 1893. 5° Yamasaki. Z. f. H., 1904. " HiRSCHFELD. Ergeb. d. inn. Med. u. Kinderheilk. 191 1. " B. Fischer. M. 1911, p. 220. ^5 Meyer. F. Z. 19 ii, viii. " Dietrich. D. 190S, 27. *' Pappenheim. F. H. xii. i, p. 26 (1911). " Helly. Naturforscherversammlung, 1908, ref. F. H. x. 2, p. 60. " Mabee. Meeting of American Assoc, of Path, and Bact. at Chicago, 1911. ^'Milligan. Manch. Path. Soc, March 10, 1909. *' See ref. 50, Chapter III., refer to Plate IV., Fig. 193 in that ref. ™ Hertz. F. H. xiii. i, p. 177. •' Hedinger. F. Z. vii. No. 3. «2 Klose. B. z. k. Ch. Bd. 74, p. 20. •' Pappenheim's Comment on Paltauf. W. K. W. 1912, No. i (F. H. xii. 2, p. 272). " Buschke und Hirschfeld. F. H. xii. Plate v. •'Pappenheim. F. H. xii. i, Plate I. sub lb. ; Atlas, Supplbd. Taf. 36. •' Gruner. Bull. Roy. Vict. Hospital, No. 2, 1912, p. 59. " Pappenheim. Prolegomena, F. H. xii. 2, p. 257, and others. '* Kanter, Goldmann. F. H. vii. p. 46 (quoted by Pappenheim). " Lewin. F. H. viii. p. 21, 1909. Also, K. Ziegler, Die Hodgkinsche Krankheit, Gustav Fischer, Jena, 1911 (with full literature). Other references in F. H. vii. pp. 177-192 (on Lymphosarcoma), pp. 153 sqq. (on Pseudoleuksemia) . ™ See ref. 29, and 2. " M. B. Schmidt. Z. f. a. P. 1907, xviii. 15. '>' La Roy. Ann. de Soc. de Med. de Gand 89, p. 209 Pappenheim, Prolegomena, F. H. x. 2, p. 3. Micheli. Haemolytic Splenomegaly, W. K. W. 1911, p. 1269. " Aschenheim and Benjamin. D. A. Bd. 97, H. 5, 6. " FoA. Pathologica, 1910 (Note di ematologia). " Pappenheim. See ref. log. Chapter t. Recent good text-book should be consulted : Gulland and Goodall, The Blood, H. K. Lewis, London. 337 GLOSSARY OF HiEMATOLOGICAL TERMS. Adventitial Cell. Syn. : clasmatocyte, perithelial cell. The cell lying immediately external to the capillary wall. See Marchand's wandering cell. Agranuloplastic. Formation of non-granular cells. Inability to form granular cells. Aleukaemia. Syn. : lymphadenia ossium (Nothnagel). See Myeloma. A disease in which the organs show the histological changes of leukaemia, but the blood does not. It is a lymphadenoid metaplasia of the bone- marrow, displacing the erythroblastic tissue and so causing " anaemia." No outpour of abnormal cells, but cell-production increased. Aleuksemic Diffuse Marrow Hyperplasia. See Latent leukaemia. Aleuksemic Lyniphosarcoinatosis. See Lymphosarcoma. Aleukaemic Malignant Lymphadenoid Lymphadenoma. See Pseudo- leukaemia. Alibert' s Granulosarcoid. An anomalous form of sarcoma. o-Granule. Eosinophile granule. a-Prothrombin. See Prothrombin. a-Substance. Syn. : reticular substance of Cesaris-Demel (q.v.). Sub- stantia reticulo-filamentosa. Alymphopotent. Devoid of the power of giving rise to lymphoid cells. Amammalian Blood-cell. Such as occurs in animals other than mammals. Amblychromasia, Amblychromatic. Having a scanty amount of chromatin. The nucleus therefore stains faintly. Ametachromophile. See Orthochromophile. Ametaneutrophile. See Orthoneutrpphile. Amaeboididity. Having the power of locomotion. Amcebocyte. A cell having the power of amoeboid movement, e.g. neutrophile leucocyte. Amorphous Haemoglobin. See Schistocyte. Amphiblast. A term invented and solely used by Fr. Freytag to describe a ceU which he believes generates red cells from the stromata of old erythrocytes. Habitat : bone-marrow. Amphiblast = mitosis = free nucleus = red cell (!) Amphileukaemic. A leukaemic state in which the outpouring of cells corresponds to the degree of cell production. Correlated terms : sub- leukaemic, aleukaemic (q.v.). Amphipyrenin. A constituent of the nucleolus. Amphochromophilia. A dusky heliotrope colour due to the admixture within a cell of two colour constituents. Same as 22 338 Biology of the Blood-cells Amphophile. The colour effect produced by the same cell substance having material in it which can take up acid dyes, and also material which can take up basic dyes. Amphophile-basophile. The same as preceding, but with the basophile constituents in excess. Amphophile-oxyphile. The same as " Amphophile," but with the oxy- phile constituents preponderating. Amyeloic. Syn. : lymphatic. Ansemic Degeneration of Red Cells. (Ehrlich.) Syn. : polychromasia. Anaemia Pseudoleukaemia Infantum. Syn. : rachitic megalospleny. Analogues. The following examples may be instructive : — Caryogenic versus plasmatic leucocyte granule polynuclear leucocyte metamyelocyte stage large myelocyte leucoblast with myelocyte nucleus myelocyte daughter cell myelocjfte with oxyphile plasma phylogenetic promyelocyte myeloblast segmentation of nucleus autoparenchymatous metaplasia Diffuse haemoglobin Erythrocyte Jolly-body stage Megaloblast Lymphoid erythroblast Normoblast Orthochromatic erythroblast Ontogenetic Polychromoblast Protohaemoblast Pycnosis Substitutive metaplasia See also " Correlated Terms." Anaplasia. Syn. : reversionary atrophy, prosoplasia, reverse differentia- tion, embryonization, atavism. Anerythrocyte. Syn. : lympheiythrocyte, lymphoid erythrocyte. Anerythroplastic. Absence of formation of red cells. Anerythroregenerative. Absence of regeneration of red cells. Angioblast. Primitive formative vascular cell. Anisohypercytosis. The total white-cell count is increased, but abnormal neutrophile leucocytes are present. Anisohypocytosis. Syn. : leucolysis. The total white-cell count is diminished, and abnormal neutrophile leucocytes are present. Anisonormocytosis. The total white cell-count is normal, but abnormal neutrophile leucocytes are present. Aplastic. Syn. : aregenerative ; passive. Aplastic Leukaemia. (Wolff-Eisner.) See Pseudoleukaemia. Archoplasm. Syn. : paranuclear spherule. Archosoma. See Somosphere. Aregenerative. Absence of regeneration of blood-cells. See Aplastic. Astrosphere. Syn. : centrosome, attraction-sphere. A small area from which lines radiate to the neighbouring part of the protoplasm. In its centre is the centriole. Attraction Particle. See Centriole. Attraction Sphere. See Astrosphere. Glossary of Haematological Terms 339 Atypical MyelomonocYte. This cell has a dusky amphophile protoplasm. The nucleus has a structure hke that of a lymphatic large mononuclear leucoc5rte. There are no nucleoli. Auer's Bodies. Rod-like structures met with in acute leukaemic blood-cells. Augmentor (Ross). A substance which aids action of an auxetic or kinetic. Aurantiophile. Affinity for aurantia. Autochthonous. Derived from the body itself. Autonomous. Rampant, uncontrolled, independent, unbridled, and spontaneous. Autoparenchymatous Metaplasia. Metaplasia occurring in the paren- chymal cells proper to the tissues. See Analogues. Autotoxin. Toxin derived from the body tissues of the individual himself. Auxetic (Ross). A substance which excites cell proliferation. Basichromioles. The granules which enter into the composition of the caryomitom. Basicytoparaplastin. That form of basiparaplastin which occurs in the protoplasm. Basicaryoplastin. That form of basiparaplastin which occurs in the parachromatin. Includes : basiparachromatin : basophile nucleolus. Basiparachromatin. Syn. : basicaryoplastin (q.v.) Basiparaplastin. That form of paraplastin which occurs partly in the nucleus and partly in the cytoplasm. It includes : {a) Basicaryoplastin (parachromatin) and (6) Basicytoparaplastin (in the protoplasm). Basometachromophile. Staining another (metachromatic) colour with basic dyes. Basophile. Having an affinity for the basophile component of a neutral dye mixture. Basophile Bodies in Red Cells. Granules assigned the following names — Foa and Mondino's, Zenoni, Plehn's, Beck's, Heidenhain's central, Celli and Guarneri bodies, Schiiffner-Maurer-Ruze stippling, Horseley's spherules, Heinz bodies, Bloch bodies. Jolly body, Lavdowsky's nucleoids, Arnold's, Pappenheim's, Engel's nucleoids, Nissl's centrosome, C- bodies of Cesaris-Demel, Schur's basophile inclusions of Graves' disease. Weidenreich's chromatin dust, the endoglobar bodies named after Wlassow, Maximow, Bremer, Hirschfeld, Schultze, Schmauch, Mara- gliano-Castellino, Arnold-Schwalbe. Basophile Myelocyte (Dominici.) See Large lymphocyte. Basophile Nucleolus. See Basicaryoplastin. Basoplasm. The part of the cytoplasm having affinity for basic dyes. Benda Chondrosome. See Chondrosome. /3-Substance. Syn. : Heinz bodies, substantia metachromatico-granularis. /3-Granule. An amphophile granule. Bioblast (Altmann). Cell granule (q.v.). Blood Crisis, (a) Sudden appearance of large numbers of " blast " forms of red cells ; (&) Sudden appearance of leucocytes during the course of pernicious anaemia (v. Noorden) . 340 Biology of the Blood-cells Blood-disc. See Erythrocyte. Blood-dust. Syn. : Hsemoconia. Blood-pathological Monocyte See Leucoblast. Blood-plasma Cell. Syn. : Tiirk cell, phlogocyte, lymphoid marrovsr cell, irritation cell, stimulation cell, large mononuclear cell, hasmatic plasma cell, plasma cell. Blood-plastid (Minot). A red cell altered by concentrated salt solution. Blood-platelet (Bizzozzero). Syn. : elementary bodies (Zimmermann), globulins (Robin), hsematoblasts (Hayem), soterocyte. Bone-marrow Monocyte. See Myelolymphocyte. Bremer's Endoglobar Body. See Paranuclear spherule. Broad-'bodied Endothelioid Small Lymphocyte. See leucocytoid lymphocyte. Brood Cell. Mother cell. Cabot Ring. Chromatin rest. Caryogenic. Syn. : parachromatic. See Analogues. Caryolobic. Having a lobe-shaped nucleus. Caryolysis. The process of solution of nuclear matter. Caryomicrosome. See Cell granule. Caryomitom. The formed material of the nucleus, consisting of : {a} threads disposed in a network ; (6) nuclear membrane. Includes basichromatin, basichromioles, etc., nuclear network. Caryophilia. Affinity for thiazin ammonium dyes. Caryoplasm. Syn. : oxychromatin, achromatin. The formless substance: in the nucleus occupying the meshes of the caryomitom. Caryoplastin. Syn. : parachromatin, caryogenic plastin, nuclear plastin body. The plastin substances within the nucleus. Some are ampho- basophile, some are ampho-oxyphile. Caryorrhexis. The process of fragmentation of nuclear matter. Caryosome. Syn. : nucleolus, plasmosome. Caryospherical. Having a globular nucleus. Cell Granule. Syn. : ozonophore (Altmann) ; cytomicrosome, caryo- microsome ; bioblast (Altmann) , plasmome (Wiesner) ; plasmosome (Arnold) ; microsome (Hanstein), protomere (Heidenhain) . Cellule MeduUaire Incolore. See Large Lymphocyte. Cellule Rhagiocrine. See Marchand's wandering cell. Central Particle. See Centriole. Centriole. Syn.: central particle, attraction-particle; centrosome (in- correct). The particle occupying the centre of the attraction-sphere (it is frequently double). Centrosome. Syn. : attraction-sphere {see centriole) ; astrosphere. The clear halo immediately round the centriole. Chloranaemia. Diminution of haemoglobin content. Chloroanaemia. A myelopathic chlorosis with secondary degeneration of red cells (anisocytosis, poikilocytosis) , and occasionally with regenerative- phenomena (basophilia, polychromasia). Glossary of Heematological Terms 341 Chloroblast. Syn. : lymphoid erythroblast, q.v. Chlorolyniphosarcoma. A sarcomatous variant of chloroma. Chloroma. A disease characterized by : (i) Presence of lymphoid deposits in the orbits, temporal fossse, and periosteum of the bones of the skull, and the symptoms and signs arising therefrom ; (2) Green colour of the lesions ; (3) Profound blood change ; enormous numbers of lympho- cytes ; (4) Affection of the bone-marrow, spleen, lymph-glands, and organs throughout the body (infiltration with lymphoid deposits) as in lymphatic leukaemia. ChloromyeSs.' 1 ^"^^^^^^ *''"'°"'' '"^ ^°°^' °^ ^^'^^^ ''''^°^'- Chlorosarcolyniphadeny. See Chlorolymphosarcoma. Chlorosarcomyelosis. A sarcomatous variant of chloromyeloma. Chlorosis. A disease in which there is enfeebled power of assimilation of iron ; " hypoplasia of haemoglobin." Chondroconta. Syn. : mitochondria (q.v.), Schridde granule. A red- coloured granule (Altmann-Schridde) met with in a myeloblast. Said by Schridde to be different from 'the lymphocyte granule and from the large mononuclear leucocyte granule. Chondromitom. Syn. : paranucleus (q.v.). Chondrosome (Benda). Altmann - Schridde granule of lymphocyte, according to Meves. See Mitochondria. Chromatinic Nodal Points. Syn. : pseudonucleolus. Chromatinolysis. The process of solution of chromatin. Chromatinorrhexis. The process of fragmentation of the chromatin. Chromatokinesis. Rearrangement of the chromatin by metakinesis into wheel forms, etc. Chromatolysis. Syn. : chromatinolysis. The process of solution of chromatin. Chromidium. The central chromatic structure of the blood-platelet. Chromidia. Syn. : mitochondria, chondroconta, Schridde granule (but incorrect) . Chromidial. Derived from chromatin. Chromiole. The constituent particles of the chromosomes. Chromoblast. See Lymphoid erythroblast. Chromocyte. See Erythrocyte. Chromomere. A group of two or three chromioles bound together by linin. Chromophobic. Inability to take up a given dye. Chromoplast. A small mass of resting chromatic substance from which the chromosomes arise during division. Chromosome. The separate portions of the nuclear chromatin which appear when the nucleus is in process of division, though also present at other times. Chromotoxic Hyperchromsemia. Anaemia, associated with hyper- chromia, due to toxic action on the haemoglobin. Clasmatoblast. Syn. : mast cell. Clasmatocyte. See Marchand's wandering cell. 342 Biology of the Blood-cells Clasmatosis. The formation of pseudopodia-like processes by plasmolysis and not by true pseudopodia formation ; bud-like constrictions. Coctostable. Syn. : thermostable (not absolute syn.). Withstanding the temperature of boiling water without decomposition. Condensateur. See Plasmosome, cell granule. Cornil Lymphoid Marrow Cell. See Large Lymphocyte. Corps en demi-lune. See Fig. 27. Syn. : demi-lune body. Correlated Terms. The following are of interest : chromotoxic v. hsemo- toxic ; chromotoxanaemia v. haemotoxanaemia ; pernicious anaamia v. simple anaemia ; hjemotoxicosis v. myelotoxicosis. See Analogues. Cryptogenetic. Of obscure origin. Correlated term: phanerogenetic. Cyanophile. Having an af&nity for the blue-staining component of a neutral mixture. Cytochylem. Interspongioplastic substance. Cytode. The simplest form of cell. Cytogenesis. Cell formation. Cytokerastic. The process of " moulding " of a cell into a higher type. Cytomicrosome. Syn. : caryomicrosome ; bioblast. See Cell granule. Cytomitome. Syn. : spongioplasm. A bundle of fine fibrils traversing the cytoplasm (in a ciliated cell for instance). Cytophage. Examples are : erythrophage, leucophage, pigmentophage, protozoophage. Cytophyletic. Pertaining to the genealogy of a cell. Cytoplastin. The plastin bodies of the cytoplasm. They consist of spongioplastin and paraplastin (q.v.). Cytostromatic. Referring to the stroma of a cell. Cytozyme. Syn. : thrombokinase. Darier's Polyeidocyte. Large mononuclear leucocyte of normal spleen. o-Granule. A small mast granule. Demi-lune Body. Syn. : hsemodemilune. See Corps en demi-lune. Deviation to the left .... right. Applied to white-cell formulae to indicate prevalence (or absence) of immature forms. Deuteropathic. (a) Producing pathological effects along two directions ; (6) A secondary action of a toxic agent. Deuteroplasm. Syn. : paraplasm. The non-protoplasmic matter within a cell-body. Dihypercytosis. Syn. : hjrperhypercytosis (q.v.). Dinormocytosis. Syn. : normonormocytosis ; isonormocytosis. Dipotent. Having a potentiality for development along two directions. Discoplasm (Ehrhch). A part of the cytoplasm which possesses vital properties. Discostroma. The stroma of the red cell. Dwarf Leucocytes. Miniature forms. Elementary Bodies (Zimmermann). See Blood-platelet. Embryonic Erythroblast. Syn. : primary erythroblast (Schridde), megaloblast (Ehrlich). Glossary of Haematological Terms 343 Embryonization. Reversion of a cell or tissue into an embryonic form. See Anaplasia. Enchylema (Carnoy). See Hyaloplasm. Endoglobar Body (of red cell). See Nucleoid. Endointoxication. Intoxication of the tissue by an endogenous toxin. Endosoma. (Weidenreich). A hypothetical solution of hsemoglobin occupying the red cell. Endothelial Cell (fixed). Syn. : lymphatic clasmatocyte, mesenchymal ceU. Endothelial Lymphocyte (Patella). Syn. : leucocytoid lymphocyte, Schleip's hypertrophic lymphocyte ; Pappenheim's indent-nucleated leucocytoid lymphocyte ; senUe lymphocyte ; hyaline lymphocyte ; hyaline leucocyte ;* large mononuclear leucocyte (q.v.). Endothelial Micromonocyte. See Lymphocyte. Endothelioid Habit. A condition in which the nucleus is relatively small in volume compared with the cytoplasm (broad cell-body). Endothelioid Leucocyte. Syn. : leucocytoid leucocyte. Endothelioid Lympholeucocyte. Syn. : Schridde's lymphoblast. Endothelioid Pseudolymphocytar Micromonocyte (Patella)) is a large mononuclear leucocyte. Endothelio -vascular Cell. See Large mononuclear leucocyte. Endotoxicosis. Disease due to poisoning by endotoxin. Endotoxinsemia. The presence of endotoxin in the circulating blood. Engel's Fuchsinophile Cell is a polychromatic erythroblast, which takes on a pink colour with the fuchsia of triacid. Eosinoblast. Syn. : microleucoblast ; micromyeloblast. Fate — becomes a micropromyelocyte with alpha granules. Eosinopenia. A condition in which the number of eosinophiles in the circulating blood (or in a tissue) is diminished. Eosinophile Leucocyte. See text. Eosinophile Promyelocyte. An eosinophile cell whose nuclear charac- ters are those of a promyelocyte. Eosinotactic. Having an attractive or repulsive action on eosinophile cells. Epigenetic. Pertaining to the growth and differentiation of a single egg-cell. E-Leucocyte. See Neutrophile Leucocyte. ^-Myelocyte. See Neutrophile Myelocyte. Ergastoplasm (Ciaccio). The prezymogenic substance of basophile reaction which appears in glandular cells before the formation of vacuoles or secondary granules within them. Erythrsemia (Lowit, v.d. Stricht). Syn. : polycythaemia (q.v.). * It will be evident that each of this list of synonyms is not synonymous with every other 344 Biology of the Blood-cells Erythroblast. Syn. : lymphoid erj^hroblast ; chloroblast ; chromoblast : protohasmatoblast (Malassez) ; hematie secondaire (Jolly) ; hsemoblast (Pappenheim) ; erythroblastic erythrogonia (Helly) ; lymphocyte (Weidenreich) ; large lymphocyte (Maximow) ; lympherythroblast ; proerythroblast (Zoja, Ferrata, Dantschakofi) ; haemonormoblast ; hsemerythroblast ; lymphoid haemoblast ; normoblast. Erythrocyte. Syn. : erythrocytode ; mononuclear mammahan red blood- corpuscle : blood-disc ; chromocyte ; red cell. See Analogues. Erythrocytoblast (Zoja). Syn. : lymphoid haemoblast. Erythrocytode. See Erythroc5rte. Erythrocytosis. Syn. : polycythsemia (q.v.). Ery thro dysplasia (of bone-marrow). A state in which there is interference with the process of differentiation of the erjrthropoietic cells, due to : (i) Primary leukaemic change ; (2) Secondary to regenerative changes. Variant : aplastic anaemia (aregenerative anaemia). Erythrogonia (Helly). See Erythroblast. Erythrolysis. Solution of red cells ; globuUcidy ; effect of an erythrol5rtic agent. Erythroneocytosis. Appearance of regenerative immature forms of red cells in the blood. Erythrophile. Having an affinity for the fuchsin component of triacid. Erythrorrhectic. The fragmented condition of an erythrocyte discharged into the circulating blood, or taking place as a result of noxae. Eumorphism. A pathological change, but without disturbance of the natural form or shape of the ceU. Exotoxic. A toxic process introduced from without the body. ExtrameduUary (Heterotopic) Myeloid Tissue Formation. See Myeloid transformation. False Anaemia. Where the patient looks anaemic, but the blood-count is normal. Filar Mass. Syn. : See Reticular substance. Filar Structure. The reticular matter of young erythrocytes which stains by vital staining. See Reticular Substance. Fuchsinophile. Syn. : Erythrophile (Engel). Having affinity for the fuchsin of triacid. It is not the same as polychromatophil, and cannot be detected by Romanowsky stains. 7 -Granule. A large mast-cell granule. Germ-centre Cell. Syn. : lymphogonia (Benda), lymphoidocyte, inter- foUicular germ-centre cell, intrafoUicular germ-centre cell, monocyte, large lymphocyte. Ghost Corpuscle. A shadow form of blood-cell (whether red or white). Giant Leucocyte. A very large form of polynuclear leucocyte, occasion- ally encountered in blood smears. Gigantoblast. Possible Syn. : megaloblast. Gigantochromoblast. Syn. : gigantoblast. A large nucleated red cell. Glossary of Haematological Terms 345 Gigantocyte. A very large red cell. Gigantolymphocyte. Applied to Naegeli's lymphoblast, and to the meso- lymphocyte. Glass-body. See text and Fig. 23. Globulicidy. Syn. : er5rthrolysis. Globulin of Robin. See Blood-platelet. Granoplasm. The portion of the cell-substance which has a granular appearance, but is not possessed of true granules in the Ehrlich sense. Granular Pseudolymphocyte. Syn. : promyelocyte. Granuloblast. Syn. : large lymphocyte. The mother cell of a granulocyte. Granulocyte. A white cell of the blood which contains specific granules. Granuloplastic. Syn. : granulopotent. Having the potentiality of forming granules. Granulopotent. See Granuloplastic Granulopotent Leucoblast. See Leucoblast. Granulosarcoid. A form of sarcoma. Guaiac Reaction of the Blood. The blue colour obtained by addition of tincture of guaiac alone, found in chronic mixed leukaemia. Haematoblasts (Hayem). See Blood-platelets. Hsematogonia. See Haemogonta. Haemobasocyte. Basophile (immature) red cell devoid of nucleus. Haemoblast, Lymphoid. See Lymphoid Erythrocyte, Erythroblast. Hsemoconia. See Blood-dust. Haemogonia. See Large lymphocyte. HEemonormoblast. See Erythroblast. Haemosemeiological. Pertaining to the symptoms of blood-disease. Heinz Body. See text. Syn. : /3-substance, reticular substance (q.v.) : Howell nuclear rest; Schmauch's endoglobar body. Hematie Granuleuse. See Reticular Substance. Hematie Secondaire (Jolly). See Erythroblast. Hepatothrombin. A substance antagonistic to fibrinolysis. The action of leucothrombin derived from the liver. Heterometaplasia, Heterometaplastic. A metaplastic process resulting in the production of an apparently foreign tissue. Heteroplasia, Heteroplastic. A specific differentiation in another direction than physiological. This may be indicated by the admixture in the cell-body of lymphospongioplasm and oxyparaplasm. Heterotopia. The appearance in the blood of immature ancestors of the leucocytes. Also applied to the appearance of any cell in a region in which it is normally absent. Adj. : Heterotopic. Heterotopic Myeloid Tissue Formation. See Myeloid transformation. Histiogenic. Syn. : histioid. Arising in tissues, as opposed to the blood. Histiogenic Lymphocyte. Syn. : lymphocytiform microleucoblast ; myeloic lymphocyte, myelolymphocyte, pseudolymphocyte, microlymph- oidocyte ; small lymphocytoid cell, micromyeloblast, eosinoblast. See also under Permanent Lymphocyte. Properties : possession of granulo- plastic power. Fate = histiogenic eosinophile. 346 Biology of the Blood-cells Histioid. Syn. : histiogenic, histogenic. Histio-irritative. Tending to irritate or excite the connective tissues. Histiometaplastic. Having the power to give rise to metaplasia of tissue. Histothrombin. A thrombin derived from the connective-tissue cells. Holozyme (Fuld). Syn. : thrombin. Homogeny. Identical structure inherited from an ancestor common to two cells or organisms being compared. Homohyperplastic. Excessive overgrowth with production of similar cells. Homoioplastic (Pappenheim) . Where the daughter cells are exactly- like the mother cell. Homophane. Without optical differentiation. Homoplastic. Formation of a highly-developed tissue from an apparently undifferentiated cell. Homoplasy. Independent development of like structure along two different lines of descent. Hyaline Leucocyte. See under " EndotheUal Lymphocyte." Hyaloplasm (Leydig). Syn. : enchylema. The clear substance which occupies the meshes of the spongioplasm. Hyperchromatic Macrocytosis. Syn. : macrocytar hyperchromia. Hyperchromia. Syn. : pleiochromia. Hyperchromic Anaemia. When the colour index is greater than unity. Hyperchromophile Chromotoxic Anaemia. See Chromotoxic hyper- chromanjemia. Hypercytochromia. A sign of degeneration of the blood. Hypercytosis. Syn. : leucocytosis ; neutrophilia ; hyperorthocjrtosis. An increase in the number of leucocytes. Hypereosinophile Granulation (Miiller and Rieder). Granules that stain unduly brilliantly with eosin, but occur in cells otherwise classifi- able as neutrophile leucocytes. Hyperglobulism. Syn. : polycythasmia (q.v.). Hyperhypercytosis. Syn. : di-hypercytosis. The total white count is increased, the neutrophile percentage is excessive. Hyperhypocytosis. The total white count is diminished, the neutrophile percentage is increased. Hyperleucocytosis. See Leucocytosis. Hyperneocytosis. Syn. : hyperskaecytosis. The total white count is increased. Along with this is deviation to the left. Hypernomic. Pertaining to unduly vigorous independent and uncontrolled proliferation. Hypernormocytosis. The total white-cell count is normal. The neutrophiles are relatively increased. Hyperplasmia. An increase in the size of the red cell from imbibition. Alt. : an aleukemic excessive proliferation of the normal cells prevalent in the organ concerned. Hyperorthocytosis. See Hypercytosis. Glossary of Haematological Terms 347 Hyperplasia. The over-proliferation of normal cells, which are in any case predominant in the given tissue or organ. Hyperplastic Aleukaemia. Syn. : aleukaemic lymphocytomatosis ; aleukasmic leucocjrtomatosis ; malignant hyperplastic aleukemic lymphoma ; lymphomatosis (Trousseau) ; lymphadenomatosis ; lymphadeny; malignant lymphona (Orth). Generalized hyperplasia of the lymphadenoid tissue, or myeloid tissue. Hyperskaeocytosis. See Hypemeocytosis. Hypertrophic Lymphocyte (Schleip). See Endothelial lymphocyte. Hyperchromatin. The azurophile portion of chromatin. Hypochromic Anaemia. Where the colour index is less than unity. Hypochronological. Shifting back of the development of a blood-cell to an earlier period of time. Hypocytosis. The total white count is diminished. See Leucopenia. Hyponeocytosis. Syn. : hyposkaeocytosis. The total white count is diminished, and there is deviation to the left. Hyponeutrophile. Immature neutrophile granules. Hypo-orthocytosis. Syn. : hypocytosis, leucopenia. The total white count is diminished, but only mature cells are present. Hypoplastic Monster (Pappenheim). Applied to the lympherythrocyte. Hyposkaeocytosis. See Hyponeocytosis. Idiozome. A body occurring within red cells, leucocytes, and epithelial cells. Immature Cells (Grawitz). See Large lymphocyte. Immature Leucoblastic Parenchymal Cell. See Marchand's wander- ing cell. Immature Lymphoblastic Parenchymal Cell. See Marchand's wandering ceU. Immature Monocyte. A transitional form of monoc5rte. Immature Myelocyte. Syn. : leucoblast. Inclusion Body. See Nucleoid. Indenization. See Inniadation. Indifferent Cell. A cell capable of metaplasia. See Lymphoidocyte. Indifferent Lymphomyeloblast. See Large lymphocyte. Indifferent Marro^w Cell. A cell occurring in the marrow, having potentiality for development along different directions. It has a narrow reticular basophile protoplasm, and a large simple badly staining nucleus. See Large lymphocyte. Indifferent Mesenchymal Primordial Cell. See Large lymphocyte. Inniadation. Syn. : indenization, colonization, metastasis. Applied to ceUs which, carried from one part of the body to another, settle in the new situation, and multiply there. Interfollicular Germ-centre Cell. A cell in the resting stage, and yet capable of developing a new germ centre, on occasion. Interfollicular Tissue. Syn. : non-specific lymphadenoid tissue, cir- cumvenous perivascular tissue ; extra-parenchymatous tissue. 348 Biology of the Blood-cells Interphyletic. Morphological transitions between two kinds of cells during the course of metaplastic differentiation. Interspongioplastic Substance. Syn. : cytochylem. Intrafollicular Germ-centre Cell is one in a state of lymphoblastic metamorphosis (actively proliferating and differentiating). Intraphyletic. Morphological transitions of development during the course of life of one and the same kind of cell. Irritation Cell. See Blood-plasma cell. Irritation Cell Leucocytosis. Syn. : phlogocytosis, plasmacytosis, plasma-cell leucocytosis. Irritation Myelocytosis. An increase of the myelocytes with plasmoid change. Isochromatophile. Having the same affinity for a given dye. Isogenesis. Identity of morphological development. Isohypercytosis. The total white-cell count is increased, but the neutrophile percentage is normal. Correlated term : aniso-hyper- C3rtosis. Isohypocytosis. Syn. : leucopenia. The total white-cell count is diminished ; the neutrophile percentage is normal. Correlated term : anisohypocytosis. Isomorphous. Having the same morphological characters. Isomorphous Cells. Large mononuclear leucocyte with leucoblast. Leucocytoid large lymphocyte) fleucocytoid myeloblast of patho- of normal blood . . . . ) " 1 logical blood. (leucocytoid macrolymphocyte of Leucocytoid lymphocyte . . ,, j lymphsemic blood ; leucosar- I coma cell of Sternberg. Lymphoblast . . . . ,, lymphoidocyte f lymphaemic microlymphocyte Lymphocyte . . . . ,, i microlymphoidocyte ( myelaemic microlymphoidocyte Microlymphoidocyte . . „ ' small lymphoc3rte Monocyte (broad-bodied large] (broad-bodied leucocytoid leuco- lymphocyte) . . . . | " 1 blast macrolymphocytar lymphsemic Ljrmphoidocyte . . . . ,, ^ lymphadenoid leucosarcoma I cell Transition cell . . . . „ leucocjrtoid leucoblast Isonormocytosis. Syn. : normonormocytosis ; di-normocytosis. The total count is normal, and neutrophile percentage is normal. Correlated term : anisonormocytosis. Isotypical. Belonging to the same type. Jolly Body. See text. Syn. : nuclear spherule, chromatin rest. See Analogues. Glossary of Haematological Terms 34& K-Granule. The azur-granule. Karyogenic ] Karyogenic Plastin Karyolysis Karyomicrosome Karyomitom , „ ^ ■, u.^ r^ ■ Karyophilia ^ ^^^ """"^^^ ^^"^"^ ^ ^^ ^^^=1^ ''^^^■ Karyoplasm Karyoplastin Karyorrhexis Karyosome Kinetic (Ross). A substance which excites amoeboid movement. Kinoplastic. Pertaining to the process of laying down the " anlage " f or a locomotor tissue. Krompecher's Fibroblast. A form of plasma cell. Krompecher Mast Cell. A plasma cell with coarse basophile granules. Large Leucocytoid Lymphocyte (Helly). Syn. : Pappenheim's lymphoid leucocyte. Large Lymphocyte. For the most part the synonyms of this term are identical with those for the term Lymphoidocyte, and are entered under that heading. Large Mast-cell Lymphocyte. Syn. : lymphoidocytar mast cell. Large Monocyte. Syn. : monocytoid large lymphocyte. Large Mononuclear Leucocytes include (a) irritation forms ; (6) Naegeli's myeloblasts (Turk's lymphoid marrow cells) ; (c) neutrophile myelocytes ; (d) true large mononuclears. Other ,Syn. : leucomonocyte, pathological monocyte, lympholeucocyte (q.v.), monocyte, large lymphocyte, leucocytoid lymphoc5rte (Schridde, Helly), leucocytoid large lymphocyte, hyaline leucocyte, lymphoid leucocyte, macrocyte (Schafer), maker of macrocytase, splenocyte (Turk),. splenoblast, transitional cell. Patella's desquamated endothelial cell, endotheliovascular cell, protozoophage, cytophage, lymphomonocyte, normal monocyte, splenomonocyte. Large Myelocyte. See Analogues. Large Myelolymphocyte. See Lymphoidocyte. Latent Leukaemia. Syn. : medullary pseudoleukemia, aleukaemic diffuse bone-marrow hyperplasia, subleuksemic diffuse bone-marrow hyperplasia. Lavdowsky's Nucleoid. Syn.: paranuclear body, Bremer's endoglobar- body, centrosome. Leptochromatic. Having a delicate chromatin network. Leucaemia. See Leukaemia. Leucoblastic Lymphocyte. See Myelolymphocyte. Leucoblastic Monocyte. See Monocyte, myelolymphocyte. Leucoblastic Plasma-cell. A leucoblast which has changed into a plasma-cell. Leucoblast with Myelocyte Nucleus. Syn. : lymphoid myelocyte. 350 Biology of the Blood-cells Leucoblast. Syn.: blood-pathological monocyte, bone-marrow monocyte, granulopotential leucoblast, histiogenic lymphocyte, leucoblastic lymph- ocyte, leucoblastic monocyte, leucoblastic myelomonocyte, lymphoid ancestor of granulocyte, lymphoid bone-marrow cell, lymphoid myelo- cyte, lymphoidocyte undergoing granuloplasia, microleucoblast, micro- myeloblast, micromyelolymphocjrte, monoc3rte of pathological blood, myeloic leucoblast, myeloic monocyte, myeloic splenocytoid cell, myelolymphocjrte, myelomonocyte, eosinoblast, pathological leucocytoid (Marchand) monocyte, pathological monocytoid lympholeucocyte, myelogonium (Benda, Aubertin). See Lymphoidocyte, Histiogenic lymphocyte. Analogues. Leucocyte. See Neutrophile leucocyte ; large mononuclear leucocyte. Leucocytoblast (Zoja). Parent cell of leucocytes. Leucocytoblastoma. See Lymphosarcoma. Leucocytoid Habit. Where the ratio between nucleus and plasma is small owing to the enlargement of the cytoplasm. Leucocytoid Leucocyte. Syn. : endothelioid leucocyte. Leucocytoid Lymphocyte, Syn. : leucocytoid microlymphoc3rte. A senile lymphocyte. Leucocytoid Microlymphocyte. A senile lymphoc3rte. Leucocytoid Mesolymphocyte. A senile mesolymphocyte. Leucocytoid "Wandering Cell (Marchand). Syn. : Metchnikoff's endothelioid macrophage. See Marchand's wandering cell. Leucocytoid Wandering Cell (Sternberg). See Myeloblast. Leucocytosarcoma. See lymphosarcoma. Leucocytosis. Syn. : neutrophilia, hypercytosis, hyperleucocytosis poly- nucleosis, hyperorthocytosis. Variants : hypernormocytosis, hyper- hypocytosis, hyperhypercytosis, dihypercytosis, isohypercytosis. Con- ditions in which the total white-cell count is increased. Leucolysis. Syn. : anisohypocytosis. Leucoma. Correlated term: lymphoma. A tumour made up of cells belonging to the leucocyte series. Leucomonocytar Plasma-cell. A plasma-cell with nuclear characters as of a lympholeucocyte. Leucomonocyte. Syn. : lympholeucocyte, large mononuclear leucocyte (q.v.), pathological monocyte. Leucopenia. Syn. : hypocytosis, isohypocytosis. Variants : hyponeo- cytosis, hyposkasocytosis, hypo-orthocytosis, anisohypocytosis. Condi- tion in which the total white-cell count is diminished. Leucopoietic Tissues. Tissues concerned in the formation of white cells in general. Leucosarcoma Cell. Leucosarcoma cell of Sternberg. Syn. : Rieder cell. Leucosarcoma. Syn. : leukemia sarcomatosa, sarcoleukzemia, Kelly's leucocytoid lymphosarcoma. Leucosarcomatosis. An acute disease which is histologically sarcoma, cytologically a proliferation of large lymphoid leucocytes (lymphoido- cytes) (Sternberg). Glossary of Heematological Terms 351 Leucothrombin. A substance derived from the leucocytes, which unites with thrombokinase. Leukaemia. A malignant primary hyperplasia of the haemopoietic tissues clinically associated with blood changes of specific type. Syn. -. status leukseminicus. Leukaemic Lymphosarcomatosis. See Lymphosarcoma. Leukaemia Carcinomatosa. See Leucosarcoma. Leukaemia Correlations. Myelogenic leukaemia, myelaemia ] , , . , , (EhrHch) J '■Y^V"^'^^'^ leukaemia, lymphaemia Myelocyte leukaemia (Walz) . . lymphocyte leukaemia Mixed-ceU leukaemia (Pappenheim, ) , , . , , , Grawitz) ... . _ | lymphoid leukemia PoiMlocyte leukaemia (Lowit) . . homoiocyte leukaemia Bone-marrow leukaemia (Lazarus) . . lymphatic leukaemia Lieno-meduUary leukaemia of older! lymphatic leukaemia of older authors . . . . . . f authors Intermediate form = lymphoid-cell leukaemia of Wolff. Leukanaemia. A variant of the leukaemic process wherein the virus causes cytoplastic action + haemotoxic haemorrhagic change ; or, it may be described as a haemotoxic process in which the haemotoxic virus causes lymphoblastic or leucoblastic reaction just as with other infections and intoxications, but passes on to hyperplasia. Hypermetaplastic anaemia ; hasmointoxication ; metahyperplastic infection + anasmia ; myeloleukaemia associated with pernicious anaemia. Leukine (Schneider). Syn.-. endolysin (Petterson). A moderately thermo- stable bactericidal substance present in leucocyte extract. Linin. An oxyphilic material of thread-like form which joins the nodes of the nuclear network. Lipoferous Granules. (Ciaccio). Syn. : sudanophile granules. Lipoferous Leucocyte. (Ciaccio). Leucocyte containing granules stain- able with Sudan. Lymphadenoid Aleukaemia. See Pseudoleukemia. Lymphadenoid Cell. A cell derived from a lymphocyte-forming tissue. Lymphadenoid Leucocyte. A leucocyte derived from a lymphocyte- forming tissue. Lymphadenoid Tissue-cell. See Lymphocyte. Lymphadenomatosis is aleukaemic or leukaemic. Syn. : lymphadeny, lymphadenosis (Schridde) ; lymphocytomatosis (micro-, macro-), each of the latter is follicular or diffuse. Lymphatic. Syn. : amyeloic. Pertaining to the lymphocyte series of cells. Lymphatic Clasmatocyte. Syn. : fixed endothelial cell. See endothelial cell. Lymphatic Lymphocyte. See Lymphocjrte. Lymphatic Monocyte. Syn. : agranuloplastic monocyte of normal blood. A cell derived from the interfollicular tissue of glands, and lying in normal pulpar tissue. 352 Biology of the Blood-cells LYmphatomYelogenic LymphocYte. See Plasma-cell. LYHipherYthroblast. See Erythroblast. LYnipherYthrocYte. Syn. : lymphoid erythrocyte ; anerythrocyte ; " hypoplastic monster." A red cell without haemoglobin or nucleus. LYmplioblast. See Myeloblast. LiYmphoblast (Naegeli). Syn. : gigantolymphocjrte, mesolymphocyte. I/Ynaphoblastic MacrolYmphocYte. See Lymphoidocyte. Lymphocerastism. The process of formation of lymphoid cells. LYmphocyte. Syn. : blood- mature lymphocyte, endothelial micromonocyte (Patella), leucocytoicl lymphocyte, lymphadenoid-tissue cell, lymphatic lymphocyte, mature lymphocyte, merozooiform reversible product of proliferation (Pappenheim), microcyte (Schafer), microlymphocyte, micromyeloblast of Naegeli, permanent lymphocyte, sessile ceU of lymphadenoid tissue, small lymphocyte. See also Histiogenic lymphoc3rte. Lymphocyte (Weidenreich). Syn. : erjrthroblastic erjrthrogonia of Weidenreich, large lymphocyte of Maximow. Lymphocyte of Myeloid Tissue. Syn. : pseudolymphocytoid myelo- blast of dualists. Lymphocytiform Microleucoblast. See Histiogenic lymphocyte. Lymphocytoblast (Zoja). The parent cell of lymphoc3rtes. Lymphocytoid Cell. A lymphocyte-like cell with round nucleus, nucleoli, and strongly basophile cytoplasm. Lymphocytoid Lymphoidocyte. Syn. : pseudolymphocyte, myeloblast, myelolymphocyte, lymphoidocyte. Lymphocytoid Monocyte. See Monocyte. Lymphocytoid Plasma Cell. A lymphocytoid cell which has become plasmoid. Lymphocytomatosis. Syn. : lymphadenomatosis. Lymphoid. Syn. : lymphocytar myeloblastic cell. See Lymphoid cell. Lymphoid Ancestor of Granulocyte. See Lymphoidocyte. Lymphoid Bone-marrow Cell. See Myelolymphocyte. Lymphoid Cell. Any non-granular basophile cell. Includes the following : lymphoidocyte (q.v.), large lymphocyte of Ehrlich, myeloblast and lymphoblast of Naegeli and Schridde, Pappenheim's indifferent lympho- myeloblast, Troje's lymphoid marrow-cell, true lymphocyte, large mononuclear leucocytes, etc. Lymphoid Erythroblast. See Erythroblast ; Analogues. Lymphoid Erythrocyte. See Lympherythrocyte. Lymphoid Gigantohaemoblast. A giant megaloblast without haemoglobin. Its cytoplasm is absolutely basophile. Lymphoid Haemoblast. See Erythroblast. Lymphoididity. Having a lymphoid character. Lymphoid Leucoblast. Syn. : myeloblast, partly differentiated lym- phoidocyte. Lymphoid Leucocyte (Ehrhch). Syn. : monocyte, large leucocytoid lymphocyte. (Helly). A trachychromatic lymphocyte. Lymphoid Leucocyte. (Sternberg). See Myeloblast. Glossary of Heematological Terms 353 Lymphoid Marrow-cell. Syn. : blood-plasma cell, irritation cell, large mononuclear cell, phlogocyte, stimulation cell, Ttirk cell. See also Leucoblast. Lymphoid Myelocyte. Syn.: lymphomyelocyte ; leucoblast with myelo- cyte nucleus. Lymphoidocytar(-oid) Plasma-cell. A plasma-cell possessing the nuclear characters of a lymphoidocyte. Lymphoidocyte. The following synonyms are to be found in the literature : — Autoparenchymatous proliferating myeloid parent cell. Basophile mononuclear. Basophile myelocyte (Dominici). Benda's lymphogonia. Cellule medullaire of Cornil. Cellule medullaire incolore of Engel. CornU-Miiller non-granular marrow-cell. Endothelioid lymphoc5rte (Patella). Endothelioid macrophage (Metchnikofi) . Erythroblastic erythrogonia. Fleming's germ-centre cell. Germ-centre cell of Flemming. Giant lymphocyte. Gonocyte (Pappenheim) . Granuloblast. Grawitz immature cell. Haematogonia. Hasmogonoc5rte. Hsemocytoblast (Zoja). Hffimomacrophage (Metchnikoff). Homogeneous uninucleate cell (Schleip). Hyperplastic lymphocyte. Hypertrophic lymphocyte. Immature cell of Grawitz. Indifferent cell. Indifferent lymphoid cell (Michaelis). Indifferent lymphoid primitive cell (Wolff). Indifferent lymphomyeloblast (Pappenheim). Indifferent marrow-cell of Troje. Indifferent mesenchymatic parent cell. Indifferent parent cell. Large myelolymphocyte. Leucoblast. Leucocyte mother cell. Leucosarcoma cell (Sternberg). Lymphadenoid spleen pulp cell. Lymphoblast (Naegeli). Lymphoblastic macrolymphocyte. 23 354 Biology of the Blood-cells Lymphoidocyte. Synonyms {continued.) : — Lymphocjrte of Weidenreich. Lymphocytogonia. Lymphogonia (Benda, K. Ziegler). Lymphoid ancestor of granulocyte. Lymphoid cell (Turk). Lymphoid marrow-cell (Troje). Lymphoid primitive cell (Wolff). Lympholeucoblast. Lymphomacrophage (Metchnikoff) . Lymphomyeloblast. Macroly mphocy te . Marchand's leucocytoid wandering cell. Marrow-cell (Troje). Megakaryocyte (Maximow) . Megalymphocyte. Metchnikoff macrophage. Mother cell. Myeloblast (Schridde, Naegeli). Myelogonia (Benda, Aubertin). Myeloid large lymphocyte. Myelo-macrolymphocyte. Multivalent lymphomyeloblastic parent cell. Naegeli's lymphoblast ; myeloblast. Non-granular marrow-cell. Parenchymal cell of hemopoietic tissue. Parent cell. Patella's endothelioid lymphocyte. Perivenous endothelial cell. Perivenous perithelial cell. Polyeidocyte (Darier). Primary wandering cell of Saxer. Primeval cell. Primitive cell. Primitive lymphocyte. Primitive lymphoid cell. Primordial cell. Proliferating germ-centre cell. Proliferating lymphoblast. Pseudo-eosinophile myelocyte (Maximow). Schleip's homogeneous uninucleate cell. Splenoblastic macrolymphocyte. Splenocytar monocyte. Sternberg's leucosarcoma cell. Troje's marrow-cell. True eosinophile myelocyte. True parenchymal cell. Glossary of Hsematological Terms 355 Turk lymphoid cell. Wolff's lymphoid primitive cell. Lymphoidoma (la Roy). A tumour resulting from the proliferation of lymphoid elements. Clinically Uke sarcoma. Lympholeukaemia. A disease in which there is marked leucocjrtosis, the lymphocytes being increased ; atypical or ancestral forms occur as well. Lympholeucoblast. Syn. : immature differentiated lympholeucoblastic large primitive cell ; partly differentiated large lymphocytic myeloblast ; and all the terms given under lymphoidocyte. Lympholeucocytar(-oid) Monocyte. See Monocyte. Lympholeucocyte (Coie). Analogues : myelomonocyte, monocytoid leucoblast, pathological monocyte, K. Ziegler's myeloblast. See Large mononuclear leucocyte. Lymphomonocytar Plasma-cell. A plasma-cell originating in a large mononuclear leucocyte. Lymphomegaloblast. A megaloblast whose cell-body is devoid of haemo- globin. Lrymphomonocyte. See Monocyte, splenocyte, large mononuclear leucocyte. Lymphomyelocyte. Syn.: lymphoid myelocyte, leucoblast with myelocyte nucleus. Lymphopathy. (i) Disease of the lymphopoietic tissues. (2) Having a morbid action on the lymphatic tissues. Lymphoplasmia. Applied to red cells to express total absence of haemo- globin. Lymphoplasm. Syn. : spongioplasm. Lymphopotential. Propensity for developing along lymphoid lines. Correlated terms : myelopotential, leucopotential, haemopotential. Lymphosarcoma. Syn. : leucocytosarcoma ; leucocytoblastoma ; leukas- mic lymphosarcomatosis ; leukaemia on a sarcomatous basis ; generalized aleukaemic Kundrat's lymphosarcomatosis ; sarcoleukaemia, sarcoid variant of parenchymatous lymphocytoma formation ; aleuksemic lymphosarcomatosis. Lymphotaxis. Having the power of attracting or repelling lymphocytes. Macrocyte. See Large mononuclear leucocyte. Also, more familiarly, applied to a large specimen of a red cell. Macrocytar Hyperchromia. Syn. : hyperchromatic macrocytosis. A state in which the blood contains unduly large red cells with relative abundance of haemoglobin. Macroerythroblast. See Macronormoblast. Macroleucoblast. A leucoblast of unduly large size. Macroleucoblastic Plasma-cell. A plasma-cell derived from a macroleucoblast. MacrolymphocYtar(-oid) Lymphoblastic Plasma-cell. A plasma-cell derived from a macrolymphoblast. Macrolymphocyte. See Lymphoidocyte. 356 Biology of the Blood-cells MacrolymphocYtogenic. Giving rise to a macrolymphocyte. Macrolymphoid. Syn. : macrolymphocytar myeloblastic. Macromegaloblast. A megaloblast of unduly large size. Macromonocyte. A monocyte of unduly large size. Macronormoblast, Macronormochromoblast. Syn. : Maximow's megaloblast; macroerythroblast. A cell derived by mitosis from a mesolymphoidocyte. Macropromyelocyte. A promyelocyte derived from a macro- instead of a micro-ljTnphoidocyte. Malignant Lymphogranulomatosis. Syn. : multiple granulolymphade- nomatosis. Hodgkin's disease. Marchand's Wandering Cell. Syn. : adventitial cell, cellule rhagio- crine, clasmatocyte, immature lymphoblastic parenchymal cell, immature leucoblastic parenchymal cell, mast cell, primary wandering cell of Saxer, primitive leucocytoid wandering cell of Marchand, pyrrhol cell- Marrow Lymph Gland. Myeloid type of haeinolymphglaiid. Marschalko's Lymphocytoid Cell. See Plasma-cell. Marschalko's Plasma-cell. See Plasma-cell. Mast Cell. Syn. : clasmatocyte (Schridde). Mast Lymphocyte ) Mast Lymphoidocyte \ Cells containing mast-cell granules. Mast Myelocyte j Maturatio Antecedens Nuclei. Where maturation is relatively far advanced along ontogenetic lines ; the cell as a whole remains phylo- genetically immature. Maturatio Praecox Nuclei. Undue ontogenetic maturation. Mature Erythroblast. A non-mammalian erythrocyte with a permanent rod-like nucleus. Also inadvisedly applied to the mammalian non- nucleate erythrocyte. Mature Lymphocyte. See Leucoc5rtoid lymphocyte, lymphocyte. Mature Monocyte. Adult form of large mononuclear leucocjrte present in the blood-stream. Maximow's Megaloblast. Syn.: macronormoblast; mesoerythroblast. Medullary Pseudoleukaemia. Syn. : latent leukasmia, pseudoleukaemia. Megaloblast. Syn. : hematic primordiale (Jolly), primary erythroblast, metrocyte of first generation (Engel). See Analogues. Megakaryocyte. Syn. : myeloplax (Robin). Megalopathy. A morbid state of the bone-marrow in which megaloblasts appear in the blood. Merozoitiform Reversible Product of Proliferation. See Lymphoc5rte. Mesenchyme Cell. See Angioblast. Mesocyte. Syn. : mesolymphocyte. Mesoerythroblast. Syn. -. macronormoblast ; Maximow's megaloblast. Mesoleucoblast. A leucoblast of middle size. Mesolymphocytoid Plasma-cell. Syn. : mesolymphocytar irritation cell. Mesolymphocytoid Irritation-cell. See preceding. Mesolymphocyte. Syn. : lymphoblast (Naegeli) ; gigantolymphocyte. Glossary of Haematological Terms 357 MesolymphoidocYte. A lymphoidocyte of middle size. MesomicromYelolymphocYte. A redundance of terms, to express a secondary generation of myelolymphocyte. Mesonormoblast. A normoblast of middle size. Metabasophile Granules. Granules which stain violet with eosin- orange-toluidine blue. Metachromatin. The general basophile constituent of nuclear chromatin which has an affinity for methyl green (Pappenheim) . Metahyperplasia. Hyperplasia complicated by simultaneous metaplasia. Metakinesis. The process of separation of chromosomes at the height of mitosis. MetamyeloCYte. See Analogues. Metamyelocytoid. A cell like a metamyelocyte. Metaphase. The stage in division of the nucleus at the moment of division of the chromosomes. Metaplasia. Excessive proliferation of cells which normally do not play the chief part in the histology and function of the corresponding organ. Correlated term : metahyperplasia. See substitutive metaplasia. Metathrombin. Syn. : metazyme (Fuld), /3-prothrombin (Morawitz). A substance resulting from fibrin ferment during the process of contraction of blood-clot. It is inactive. Metazyme. See preceding. Methylgreenophobic. Inability to stain with methyl green. Metrocyte of First Generation. Syn. : primordial erythroblast. See Megaloblast in text. Metrocyte of Second Generation. Syn. : secondary erythroblast. See Megaloblast in text. Metrocyte. Syn. : premegaloblast (C. P. Jones), orthochromatic megalo- blast of embryonic blood-formation. MetchnikofFs Endothelial Macrophage. Syn. : first generation of lymphoidocyte. See Marchand's wandering cell. MetchnikofFs Microphage. Polynuclear leucocyte, pulpar cell. Microcyte. [a) A small red cell ; (6) A lymphocyte (Schafer). Microleucoblast. See Histiogenic lymphocyte, myelolymphocyte, eosino- blast, micromyeloblast. Microleucoblastic Plasma-cell. A plasma cell having the fundamental characters of a microleucoblast. Microlymphocyte. A more precise description of the true lymphocyte (q.v.). Microlymphoidocytar Myelolymphocytic Leukaemia. A redundance of terms. Leukaemia with preponderance of microlymphoidocytes in the blood. Microlymphoidocyte. Syn. : micromyeloblast, myelolymphocyte (q.v.). A daughter lymphoidocyte. Micromegaloblast. A daughter megaloblast. Micromyeloblast. See Histiogenic lymphocyte, myelolymphocyte. Micromyelocyte. A myelocyte daughter cell. 358 Biology of the Blood-cells MicromyelolyniphocYte. See leukoblast. Microphage. (Metchnikofi). See under Metchnikoff. Micropoikilocyte. A small poikilocyte. A good sign in pernicious anaemia. Micropromyelocyte. A daughter cell of a promyelocyte. Microsomes. (Hanstein). See Cell granule. Microsplenocyte. Syn. : leucocytoid lymphocyte. Mitochondria. Syn. : chrondrosome, chondroconta, Schridde granule, chromidia (according to some). Cell granules which tend to form fibrillffi, and are stainable with ease. Mitochrome. A longitudinal fold observed in the nucleus of spindle cells. Monochromatophile. Syn. : orthochromatic. Opposite of metachro- matism. Monocyte. A dual term to describe certain cell-forms : a senile form of large lymphoblastic lymphocjrte (Weidenreich, Helly), a senile form of myeloblast or leucoblast (Ziegler), a senile splenocyte. It is representa- tive of a third branch of differentiation of the lymphoidocytar parent cell (the other two being the lymphocyte and the neutrophile lines of development). Normal monocytes are : lymphatic monocyte {Syn. : large mononuclear of normal blood ; splenocyte), lymphocytar monocyte, lymphomonoc3rte, splenocytar monocyte or germ-centre cell, spleno- monocjrte. Pathological monocytes are : (a) Senile lymphoblastic macrolymphocyte ; (6) The myeloic leucoblast {see Leucoblast). Syn. : leucoblastic monocyte, myelomonocyte, lympholeucocytar mono- cyte, ancestor of polynuclear leucocyte, progeny of lymphoidocyte ; resting interfollicular cell ; spleen-pulp cell. Monocytoid Large Lymphocyte. Syn. : large mononuclear leucocyte of Ehrlich. Monocytopenia. Diminution of the number of monocytes in the blood. Monocytosis. Possible syn. : myeloblastic leukaemia. Preponderance of monoc5rtes in the blood. Mononuclear Mammalian Red Blood Corpuscle. Syn. : Erythrocyte. Monophyletism. The doctrine which derives all blood-cells from one ancestor. The two following schemes may be quoted : Old view (Maximow, Erik Meyer, v. Domarus, Hirschfeld) : Large lymphocjrte (= myeloblast + lymphoblast) ^myelocyte lymphocjrte leucocjrte More modern view : Lymphoblast or lymphoid cell (not in normal blood). / ! \ / ^ \ all blood cells Mother Cell. Syn. : brood cell, primordial cell. Miiller's Lymphoid Marrow Cell. See Lymphoidocjrte. Multiple Granulolymphadenomatosis. The same as mahgnant lym- phogranulomatosis, which is the most accurate designation for Hodgkin's disease of the Dorothy Reed type. Glossary of Haematological Terms 359 Myelaemia. Syn. : myeloid leukaemia, myeloleukaemia. Myeloblast. Closest syn. : leucoblast. See also LympIioidoc3rte. The wealth of synonyms is accounted for by the vagueness of the morphology of the cell form originally described, as well as by the fact that the cell is variable in appearance during the course of its normal life. See Analogues. Myeloblast of K. Ziegler is synonymous with Coie's lympholeucocyte, leucomonocyte, or pathological monoc3rte. Myelocyte. Syn. : mother myelocyte, myeloleucocyte, polymorphocyte (Schafer), polynu clear leucocyte (some authors, incorrect). Myelocyte Daughter Cell. See Analogues. Myelocytoblast (Zoja). The parent cell of the myelocyte. Myelocytosis. The presence of myelocytes in the blood. Myelogenic. Arising in the bone marrow ; giving rise to the myeloid series of cells. Myelogonia. Syn. : orthobasophile mononuclear, basophile myelocyte, leucoblast (q.v.). Myeloic. Belonging to that series of cells which normally terminates in a neutrophile leucocyte. Myeloic Granulation (Azur). Syn. : pseudo-azur granulation. Myeloic Leucoblast. Syn. : pathological monocyte. A redundance of terms, leucoblast being necessarily myeloic. See Leucoblast. Myeloic Lymphocyte. See Histiogenic lymphocyte. Myeloic Monocyte. See Leucoblast. Myeloic Small Lymphoid Cell. A small lymphoid cell having myeloic potentiality. Myeloic Splenocytoid Cell. See Leucoblast. Myeloid. Having myelocytar myeloblastic characters or potentialities, and not necessarily situated in the bone marrow (not necessarily " medullary "). Myeloid Aleukaemia. See Pseudoleuksemia. Myeloid Leukaemia. See Myelaemia. Myeloid Metaplasia. See Myeloid transformation. Myeloid Multiple Myeloma. A form of pseudoleukemia. Myeloidocyte. A term applied to the lymphoblast to indicate its morpho- logical resemblance to a myeloblast. Myeloid Splenocytoid Cell. See Leucoblast. Myeloid Transformation. Syn. : extramedullary myeloid tissue form- ation ; heterotopic myeloid tissue formation ; extramedullary heterotopic myeloid tissue formation ; myeloid mfetaplasia ; myelokinesis. The formation in a non-myeloid tissue of cell-aggregations which tend along the neutrophile line of development. Myeloleukaemia. A form of leukaemia in which ancestral cells of the myeloid series occur in the blood. Myelolymphoblast. See Lymphoidocyte. Myelolymphocyte. Syn. : lymphocytoid lymphoidocyte, microlymphoido- cjrte. See under Leucoblast. 360 Biology of the Blood-cells MyelomacrolymphocYte. See Lymphoidocyte. Myeloma. Syn.: lymphadenia ossium (Nothnagel), malignant plasmoma; mollities ossium (Macintyre and Down), multiple primary sarcomatosis of the bone-marrow (Buch), multiple sarcoma of ribs (Spiegelberg), myelogenous pseudoleukaemia (Zahn), primary multiple myelogenic sarcoma (Wieland), sarcomata cranii et medullas (Grawitz), sarco- matous ostitis (Hammer), senile osteomalacia (Marchand). Myelometaplastic Stimulus. An agent which excites metaplasia along myeloid lines. Myelomonocyte. See Leucoblast. Myelopathy, (i) Disease of the myeloid tissue. (2) Having a morbid action on myeloid tissue. Myelophthisic. Atrophic process in the bone-marrow whereby defective formation of red cells results. Myeloplastic. Producing myeloid tissue. Myeloplax (Robin). See Megakaryocyte. Myelopotent, Myelopotential. Having the power of giving rise to cells of the myeloid series. Myelopotentiality. See Myelopotential. Myelosarcoma. (Sternberg). Syn. : sarcomyelomatosis. Myelosis. Syn. : leukaemic myelosis, myeloic leukaemia, leukoemic lymphadenosis. Myelotorpidity. Sluggish activity of multiplication on the part of the bone-marrow cells. Myelotoxic Polynuclear. In cases in which the monoc3rtes in the blood are leucoblastic, the polynuclear leucocjrte is found to have much darker, denser, and flaky neutrophile granulation. Myelotoxicosis. A morbid condition caused by the action of a virus on myeloid tissue. Naegeli's Myeloblast. Syn.: GoodaU's primitive leucocyte; large lymphoid cell. See Leucoblast. Negative Anaemia. An anaemia shown by the presence of erythroblasts but without diminution of the red cells per cmm. (may even be increased) . Probably due to functional derangement of the spleen. Neocytosis. Syn. : skaeocytosis, normoneocytosis. Deviation to the left. Appearance of juvenile forms in the blood-stream. Variants : hyper- neocytosis, normoneocytosis, hyponeocytosis. Neodualist View. Parent cell, existing only in embryo wall of lymphatic vessel wall of blood-vessel ^-myeloblast I 4- 4. lymphoblast basophile erythroblast myelocyte ; * (true dualism, lymphocyte erythrocyte jjgiiy_ ^^^^ large lymphocyte (Schridde, Ziegler) Glossary of Haematological Terms 361 Neometaplasia. A metaplastic process in a tissue culminating in a "neo- plasm." Neoplasia. The process of formation of new growth. Neoskaeocytosis. Deviation to the left. Redundance of terms ; neo and skseo are co-equivalent. Neozyme. Activated metathrombin (by the transient action of decinormal alkali followed by neutralization with acid). Neutroleukaemia. Leukaemia in which cells with neutrophile granules are conspicuous. Neutrometachromatophile. Abihty to stain another colour with a neutral dye. Neutrophile Leucocyte. Syn. : polynuclear leucocyte, polymorpho- nuclear leucocjrte ; polymorphocyte ; Neumann's myelocyte. Neutrophile PromyelocYte. See text. Neutrophilia. Hypercytosis, leucocytosis, polynucleosis. Neutrotaxic. Having an attractive or repeUant action on neutrophile leucocytes. Normal Large Lymphocyte. Syn. : large mononuclear leucocyte. Normal Monocyte. See Monocyte. Normoblast. See text. Syn. : haemonormoblast, haemoblast, erythroblast, erythrogonia (Helly), lymphoid haemoblast, proerythroblast. See Analogues. Normocytosis. Syn. : normo-orthocytosis. The condition in which the number of white cells in the blood is normal. Normocyte. A normal red cell. Normoneocytosis. Syw. : neocytosis, skaeocytosis. The total white count is normal, but there is deviation to the left. Normonormocytosis. See Iso-normocytosis. Normomorphism. Having a normal shape of form. Normo-orthocytosis. Total white count increased, cell formula normal. See Normocytosis. Normoplasia. A specific differentiation characteristic of a cell, not exceeding the typical limits of differentiation under physiological conditions (Schridde) . Normoskaeocytosis. Total count normal, immature cells present. Noxotropic. Having an afi&nity for a particular noxious agent. Nuclear Network. Syn. : caryomitom. Nuclear Plastin Body. Syn. : caryoplastin, caryogenic plastin. Nuclear Spherule. Syn. : Jolly body. Nucleoid. Syn. : nuclear rests, inclusion-body, (a) A precipitation effect of haemoglobin ; (6) If basic, a special appearance of the basophile cell membrane. See Ladovsky's Nucleoid. Nucleolin. Syn. : pjnrenin, plastin. The constituent of nucleoli. Nucleolus. See Plasmosome, caryosome. -Oid. Suffix to imply similarity of morphology to the cell-type used as prefix. 362 Biology of the Blood-cells Oikoid. (Brucke). The supporting substance of red cells. Oligochromaemia. Diminished content in haemoglobin. Ontogenetic. Pertaining to the development of an individual cell. Depends on the formation of paraplasm. Analogue : phylogenetic Orthobasophile Granule. (Ciaccio). Granules which stain blue-black with eosin-orange-toluidin. Orthobasophile Mononuclear Cell. See Leucoblast. Orthochromasia. Total loss of basoplasm. Orthochromatic Erythroblast. See Analogues. Orthochromophile. Syn. : ametachromophile. Staining true with a neutral dye. Orthocytosis. The condition in which only mature cells are present. Variants : normo-, hyper-, hypo-. Orthoneutrophile. Syn. : ametaneutrophile. Staining true with a neutral dye. Oxycaryoplastin. Oxyphilic plastin substances in the nucleus. Oxychromatin. Syn. : oxyphile oxycaryoplastin. Example : oxjrphUe nucleolus. A substance arising from the basophile parachromatin. Oxychromiole. Oxyphile granules which enter into the composition of the caryoplasm. Oxyparaplastin is that form of paraplastin which occurs in the nucleus and in the cytoplasm. It includes (a) oxyphile oxychromatin (that part which is in the nucleus), and (6) ox3rphile oxyplastin (that part in the protoplasm). Oxyphile. Having affinity for the acid component of a neutral dye mixture. Oxyphile Intestinal Epithelial Cell. Syn. : Paneth cell. Oxyphile Nucleolus. Syn. : oxyphile oxycaryoplastin ; oxychromatin. Oxyphile Oxycaryoplastin. See preceding. Oxyphilia. Signifies replacement of basophile COOH groups in the amphophile plasma-molecule by oxyphile NHg side-chains (chromo- receptors) . Oxyplastin. Arises from basophile paraplastin. Ozonophore (Altmann). Cell granule. Pachychromatic. Having very coarse chromatin network. Pachydermia. Applied to a red cell, this term expresses increased resistance of the red cells in anasmia. Pander's Islands. Syn. : Wolff's islands. The primitive formative centres in the embryo for red cells. Paneth Cell. Oxyphile intestinal epithelial cell. Parablast (His). Syn. : mesenchyme cell, angioblast. Parachromatic. Syn. : caryogenic. See Parachromatin. Parachromatin. Syn. : basicaryoplastin, interchromatinic substance, caryoplastin. Adj. : Parachromatic. Parachromatinorrhexis. Syn.: basophile punctation (one view). Separ- ation of the parachromatin into fragments. Glossary of Haematological Terms 363 Parafunctional. Perversion of function. Paramyeloic, Paramyeloid. A tissue which, usually developing myeloid cells, now develops lymphoid cells. Paranuclear Body. See Lavdovsky's Nucleoid. Paranuclear Spherule. Syn. : archoplasm. In its centre is the centrosome. Paranucleolus. A small basophile particle attached to the nuclear envelope. Its significance is unknown. Paranucleus. Syn. : chondromitom. A spherical mass formed by the conglomerated fibrillas derived from mitochondria. Paraplasia. The analogue of aplasia {cf. aplastic anaemia versus pernicious anaemia). Paraplasm. Syn. : deuteroplasm. Is the functionating part of the cell- body. Ex. : the substance which makes hemoglobin, the substance which makes granules (oxyphile, neutrophile). Also defined as the non-protoplasmic matter within a cell-body. Paraplastin. A substance related to parachromatin. It includes the basoparaplastin and the oxyparaplastin. It is sometimes amphobaso- phile, and sometimes ampho-oxyphile. This and spongioplastin constitute cytoplastin. Paraplastin old. Having resemblance to paraplastin. Parasplenoid. Cf. accessory splenic tissue. Passive. When applied to anajmia is synonymous with aplastic. Patella's Endothelial Lymphocyte. See Endothelial Lymphocyte. Pathological Leucocytoid Monocyte (Marchand). See Leucoblast. Pathological Monocyte. See Lymphoblastic macrolymphocyte, myeloic leucoblast. Pathological Monocytoid Lympholeucocyte. S«e Leucoblast. Pathomonocyte. Syn. : rayelomonocyte, leucoblastic monocyte. Pathomorphic, Pathomorphism. Abnormal morphology. Perinuclear Granulation. (Neusser). Dark blue-black granules seen in the nuclear matter of the polynuclear leucocyte with triacid staining. It is regarded as a dye precipitation, because the granules only appear when unfiltered dye solution is used. Perithelial Cell. See Adventitial Cell. Permanent Lymphocyte. See Lymphocyte. Phanerogenetic. Applied to diseases whose etiology is known. Phlogocyte. See Blood-plasma Cell. Phlogocytosis. Syn. : plasma-cell leucocytosis. A condition in which the blood is rich in Ttirk irritation cells. Phyletic. Syn. : phylogenetic, phylogenic, pertaining to a sub-kingdom (a phylarch was the chief of a tribe). Genealogical history; evolution of a race or tribe of cells. Phylogeny. See the preceding. The process depends on conversion of paraplasm (which increases also) into oxyplasm. Analogue : ontogeny. 364 Biology of the Blood-cells Plasma-cells may be classified according to form and according to site. Syn. : Hodara-Schridde cell, Krompecher's fibroblast, Marschalko's large lymphocytiform plasma-cell (lymphocytoid cell) ; Unna's histioid fibroblastic plasma-cell. Any blood-cell may pass into a plasma-cell See text. Plasmacytosis. Syn. : plasma-cell leucocytosis. See Phlogocytosis. Plasma Daughter Cell. Syn. : lymphocjrte (incorrect). Plasmatic. See Analogues. Plasmatropinogenic. Producing effects on the plasma. Plasmobasophilia. Basophilia of the cytoplasm. Plasmodiblast. One of the constituents of the spindle cell according to Eisen. See Somosphere. Plasmolysis. Solution of cytoplasm. Plasmome (Weisner). Cell granule (q.v.) Plasmorrhexis. Fragmentation of the C3rtoplasm. Applied also to macrocytes when they break up into microcytes. Plasmosome (Arnold). See cell-granule. Syn. : condensateur (Gurwitch), vacuoles rhagiocrines de Renaut. Plasmotropic. The action of a poison on the blood by altering the hemo- globin (into metharmogoblin). Plasmozyme. Syn. : thrombogen. Plastin. See Pyrenin, Nucleolin. Plastin Bodies, -Substances. All bodies which have no ability to take up methyl green. They contain phosphorus or protein-lecithids. They include (i) spongioplastin, which is only in the C5rtoplasm ; (2) para- plastin, which is found both in the nucleus and in the cytoplasm : (fl) basiparaplastin (q.v.), (&) oxyparaplastin (q.v.) ; (3) basipara- chromatin, oxychromatin, oxyplastin, nucleolin are present in the nucleolus and not in the C5rtoplasm. Polychroinasia. Syn. : anaemic degeneration of red cell (Ehrlich). A condition in which oxyphile haemoglobin and basoplasm exist side by side. Polychromatic Erythroblast. Syn. : Polychromoblast. Polychromatic Erythrocyte. Syn. : polychromocyte. A red cell staining polychromatically. Polychromoblast. See Polychromatic Erythroblast, Analogues. Polychromocyte. See Polychromatic erjrthrocyte. Polycythaemia. Syn. : erythraemia ; erythrocytosis ; hyperglobulisni ; polycythaemia rubra megalosplenica ; polyglobulism ; Vaquez' disease (1892). Polyeidocyte (Darier). Large mononucleate cell in normal spleen. Polyglobulism. See Polyc5rthffimia. Polymorphocyte (Schafer). Syn. : polynuclear leucocyte (q.v.) Polymorphonuclear Leucocyte. Syn. : £-polynuclear. Polynuclear (ity). Syn. : polysegmented, hyperpolymorphous, poly- merization. Polynuclear Leucocyte. See text; Neutrophile leucocyte; Analogues. Polynucleosis. See Leucocyiosis. Glossary of Haematological Terms 365 Polyphyletic. Relating to several orders of cells. Polyphyletic Unitarianism. A doctrine accepting the existence of more or less indirect relationships and genetic interconnections between various orders of blood-cells. The transitions so resulting are gradual. Polyplasmia. An increase of plasma in the blood, such as occurs in chlorosis. Postpycnotic. Disappearance of the nucleus subsequently to the stage of pycnosis in the red cell (chromatolysis). Postpycnotic Chromatolysis. Ex. : Jolly body. Pre-agonic Staining. Syn. : vital staining. Premegaloblast. See Metrocyte. Primary Saxer Wandering Cell. See Lymphoidocyte. Primary Erythroblast. (Schridde). Syn. : Ehrlich's megaloblast. Primary Wandering Cell of Saxer. See Marchand's Wandering Cell. Primitive Leucocytoid Wandering Cell of Marchand. See preceding. Primordial Erythroblast. Syn. : (Ehrlich's) megaloblast. Primordial Red Cell. See preceding. Prochromatin. The special azurophile constituent of nuclear chromatin met with in protista. Proeosinophile Myeloblast (Zoja). The parent cell of the eosinophile before u-granules have appeared. Proerythroblast. (Ferrata, Zoja, Dantschakoff) . Syn. : hsemoblast. See Erythroblast . Proleukaemia. Syn. : leukanaemia. Prolymphocyte.* A cell between a lymphoidocyte and the mature lympho- cjTte. Promast Cell.* The predecessor of the mast cell. Promegaloblast.* The intermediate stage between lymphoidocyte and megaloblast. Its nucleus contains nucleoli and has a radial structure. Analogue : myeloblast. Promyelocyte.* A granular leucoblast. Syn. : granular pseudolympho- C3rte. See Analogues. Proneutrophile Myeloblast (Zoja).* The parent cell of the neutrophile before its granules have appeared. Prosoplasia. A differentiation exceeding beyond the phase of differentia- tion normal for physiological conditions. See Anaplasia. Ad], proso- plastic. Prothrombin. (Peckelharing). Syn. : a-proferment (Morawitz), a-pro- thrombin. Consists of thrombogen plus thrombokinase. Protoerythrocyte. See Protometrocyte. Protohaemoblast. (Malassez). The next generation to the primordial. cell (Jolly). See Erythroblast, Analogues. Protoleucocyte. See Protometrocyte. Protomeres (Heidenhain). A term applied to certain cell granules. * The prefix pre may be used, if preferred to pro. 366 Biology of the Blood-cells Protometrocyte (Ciaccio). The parent of the hasmoglobin and of the leucocyte series. It gives rise to (a) protoleucocyte with amblychromatic nucleus, (6) protoerythrocyte with trachychromatic nucleus. Protozoophage. A cell which ingests protozoa. Pseudo-azur Granulation. Syn. : myeloic granulation. Pseudo-leukaemia. Syn. : i, aleuksemic hyperplasia in the medullary tis.su a, 2, aleuksemic malignant lymphadenoid lymphadenoma ; 3, aplastic leu- kaemia ; 4, latent leukjemia ; 5, lymphadenoid aleukaemia ; 6, medullary hyperplastic pseudoleuksemia ; 7, myeloid aleukaemia ; 8, myeloid multiple myeloma : numbers 2, 5, 6, 7, 8 are synonymous with Cohnheim's pseudoleukasmia. PseudolyniphocYte. See Histiogenic Lymphocyte. Pseudolymphocyte (Patella). Syn. : small leucocytoid lymphocyte (Pappenheim) ; broad-bodied endothelioid small lymphocyte. Pseudolymphocytoid Myeloblast of dualists = lymphocyte of myeloid tissue. Pseudo-nucleolus. Syn. : chromatin nodal points ; chromatin inter- sections. Pseudo-oxyplasmatic. The oxyplasmic effect produced by over-staining with acid dyes. Pseudo-structure. A term applied to the filar mass. Pulpar Cell. Syn. : Metchnikoff's macrophage. The specific cell con- stituent of the spleen pulp. Punctate Basophilia. Syn. : parachromatin rest ; basophile punctation. Pycnotic. The clumping of the nucleus associated with increased intensity of staining. See Analogues. Pyrenin. Another name for plasmosome. Nucleolar matter. Syn. -. pyrenoid substance. Pyrenoid. Syn. : Meirowsky's pyrenin-plastin. Bodies having the same chemical and physical features as pyrenin. See Plastin bodies. Pyrrhol Cell. See Marchand's Wandering Cell. Rachitic Splenomegaly. Syn. : anaemia pseudoleukaemica infantum. Red Cell. Syn. : erythrocyte (q.v.). Resting InterfoUicular Cell. Syn. : splenocyte, spleen pulp cell ; normal monocyte ; lymphomonoc5rte ; splenoid cell. Reticular Substance (of Cesaris-Demel). Syn.: u-substance ; filar mass ; Rosin-Demel reticular substance ; substantia reticulofila- mentosa ; vital stainable reticular substance ; hematies granuleuses ; pseudo-structure ; vital punctation. Retroplasia. The conversion of a tissue into one further back in the stage of development. Reversionary Atrophy. The same as anaplasia. Rhagiocrine. A clasmatocyte ; a "resting" wandering cell (Maximow). Rieder Cell. The same as leucosarcoma cell. Rieder Lymphoidocyte. One having a deeply lobed trachychromatic nucleus. Glossary of Haematological Terms 367 Sarcoid Variant of Parenchymatous LYmphocytoma Formation. See Lymphosajrcoma. Sarcoleuksemia. Syn. : lymphosarcoma, leucosarcoma, leukaemia sar- comatosa. Sarcolymphadenia. Enlargement of the lymphatic glands, of sarcomatous character. Sarcomyelomatosis. Myelosarcoma of Sternberg. Sarcomyelosis. Multiple myeloma associated with sarcomatous change. Schistocyte. A fragmented erythrocyte. A burst cell whose granules are scattered some distance away. Amorphous hasmoglobin. Schizocytosis. The formation of microcytes out of macrocytes or megalo- cjrtes or gigantocytes. Fragments of red cells met with in the blood-film. Schleip's Hypertrophic Lymphocyte. See Endothelial lymphocyte (Patella). Schmauch's Endoglobar Body. See Heinz Body (sometimes synony- mous). Schridde-Hodara Plasma-cell. Syn- 1 pseudoplasma cell, hematogenic plasma-cell. See text. Schridde Granules. See Mitochondria. Schridde's Lymphoblast. Syn. : endothelioid lympholeucocyte. A large mononuclear cell with vesicular nucleus rich in chromatin. Schridde's Myeloblast. Differs from the preceding in the structure of the nucleus, the network being delicate. Schuffner Punctation. Seen in red cells in cases of tertian malaria. Secondary Erythroblast. Occurs in two forms : (a) of small size, (b) of large size. The latter is regarded by French writers as identical with the primitive erythroblast. Senile Lymphocyte. Syn. : hyaline leucocjrte ; leucocytoid lymphocyte ; indent-nucleate leucoc3rtoid lymphocyte ; Patella's endothelial lympho- cyte ; Schleip's hypertrophic lymphocyte. Sessile Cell of Lymphadenoid Tissue. See Histiogenic lymphoc3d:e ; lymphocyte. Shadow Corpuscle. Syn. : Ghost corpuscle. Applied to dying red cells, lymphocytes and other leucocytes. Skaeocytosis. Syn. : neocytosis. The same as deviation to the left. Small Leucocytoid Lymphocyte. Syn. : Patella's pseudo-lymphocyte. (•"■ See also Senile Lymphocyte. Small Lymphocyte. Syn. : microlymphocyte. See also Lymphocyte. Small Lymphocytoid Cell. A cell having morphological characters resembling those of a small lymphocyte, but not necessarily identical. See Histiogenic Lymphocyte. Somosphere (Eisen). One of the three constituents of the archosoma which enters into the structure of a spindle cell. The other two constituents are the centrosphere and the centrosome. Soterocyte. See Blood-platelet. Spermagonia. The parent cell of the spermatozoon. Spilling' s Transitional Cell. A form of transitional cell. 368 Biology of the Blood-cells Spirem. The threads of chromatin which appear during anaphase. Spleen-Pulp Cell. See Resting interfollicular cell. Splenoblast. The mother cell of the large mononuclear leucocyte. Splenoblastic Microlymphocyte. See Lymphoidocyte. Splenocleisis. Exciting the formation of fibrous tissue round the spleen by wrapping it in iodoform gauze. Splenocyte, See Resting Interfollicular Cell. Splenoid Cell. See preceding. Splenoidocyte. Syn. -. normal monocyte ; splenomonocyte ; splenoid monocyte. Splenomonocyte, See preceding, and Monocyte. Splenopathy,-ic, having a morbid action on the spleen : diseased condition of the spleen. Spongioplasm. Syn. : cytomitom, lymphoplasm. The supporting part of the cytoplasm. It consists of a globulin lecithid. Spongioplastin. See Cytoplastin. Status Leukaeminicus. See Leukemia. Stimulation Cell. See Blood-plasma Cell. Stromatocrater (Dekhuyzen). The concavity of the red cell, on the view that it has an inverted bell-form. Subleuksemic. Syn. : aplastic leukaemia, subleukaemic diffuse bone-marrow hyperplasia. A leukaemic state in which the outpour of abnormal cells is less than their production. A disease in which the blood-forming organs show leukaemic changes, the blood-film contains ancestral cell types, and yet the number of leucocytes is not increased. Subleukaemic Diffuse Bone-marrow Hyperplasia. Syn. : latent leu- kaemia. Sublymphaemia. A condition in which the total number of white cells is not increased, but there is an enormous increase in the number of lympho- C5rtes, and the blood-forming tissues show leukaemic change. Submyeleemic. Analogous to the preceding. The cell increase lies v/ith the myelocytes. Substantia Metachromatico-granularis. Syn. : Heinz body. Substantia Reticulo-filamentosa. See Reticular substance. Substitutive Metaplasia, Analogue : autoparenchymatous metaplasia (q.v.). Syn.: false metaplasia, pseudometaplasia. Sudanophile Granule. Ciaccio's lipoferous granule of the leucocyte. Sympathicotropic. Having special affinity for the sympathetic nerve substance. Sympexis, The deposition of red cells according to the laws of surface tension (M. Heidenhain). Thrombin. Syn. : Fuld's holozyme. The material which turns fibrinogen into fibrin. Thromboblast (Dantschakoff). A small basophile cell very similar to a small lymphocyte, with round nucleus. Differentiates into a thrombo- cyte with assumption of an oval shape by the nucleus. Glossary of Heematological Terms 369 Thrombocyte. (Dekhuyzen). Syn.: spindle cell, hsmatoblast (Hayem). Thromogen. Syn. : Plasmozyme. A substance present in the circulating plasma which, with thrombokinase and lime salts, forms thrombin. Thrombokinase. Syn. : cytozyme. Activator of thrombogen, supplied by the platelets and leucocytes. ThymocYte. A term introduced to indicate that the l5rmphocytoid cell of the thymus gland is not a true lymphocyte in function. Tigroid. A substance met with in nerve-cell cytoplasm. Trachychromatic. Applied to nuclei whose chromatin has the property of staining very deeply with nuclear dyes. Transitional Cell. A cell so named because it was once believed to be a transition form between the large mononuclear and the polynuclear leucocyte. See Monocyte. Troje Lymphoid Marrow-cell. See Lymphoidocyte. Trophospongium. Canaliculi traversing the cell body in some cells, and communicating with the lymph-canaliculi all round. Sometimes they are occupied by processes of connective-tissue cells. Tiirk Cell. See Blood-plasma cell. Unitarian View of Haemogenesis. lymphocyte leucoc3rtar lymphoid cell basophUe erythroblast myeloleucocyte red cell According to this, the blood is full of immature cells. Unna's Plasma-atrophic Lymphocytoid Daughter Plasma Cell. A form of plasma-cell. Unna's Plasma Cell. Any cell in an inflammatory cell infiltration which has a strongly basophile cytoplasm. It is strictly histioid. Syn. : young fibroblast, basoplasmatic fibroblast. Vacuolar Degeneration of Lymphocytes. The appearance of vacuoles in the cell-body, other than from the occurrence of plasma-cell change. Vacuoles Rhagiocrines (Renaut). See Cell granule. Vagotropic. Having special action or affinity for the vagus nerve substance. Vasothrombin. Thrombin derived from the endothelial cells lining the vessels. Vital Punctation. Syn. : filar mass. Wandering Cell. See Marchand's wandering cell. Weidenreich's Cromatin Dust. A minute Howell- Jolly body. 24 370 Biology of the Blood-cells Winkler- Schultze Oxydase Reaction. The blue colour produced within cells containing oxydase ferment, depending on a synthesis of indo- phenyl-blue out of the following reagents : (i) i per cent a-naphthol containing i per cent Nag CO 3 ; (2) i per cent aqueous dimethylpara- phenylenediainine . (NHa ,p f(i)N(CH3), It was regarded at one time as a specific means of differentiating lympho- blasts from myeloblasts. WolfPs Islands. Syn. : Pander's islands. WolfFs Pseudomast Cell. Leucocyte containing spermatozoon heads, which stain metachromatically. Xanthophile. Having affinity for the orange component of triacid. Zoja's Haemocytoblast. See Lymphoidocyte. Zooid (Briicke). Haemoglobin, which is supposed to have vital properties. 371 GENERAL INDEX. Figures in thick type indicate main references. N.B. — Consult also " Glossary," "Index of Diseases," "Index of Animals, and " Index of Authors " referred to in this Volume. Aberrant abortive hsmopoiesis, 244, 247 — cells, 136 Absolute leucocytosis, 237 Accessory factories, leucopoiesis, 282 lymphopoiesis, 122 pulp cell, 168 — spleen, 168 Achroglobins, 92 Acid granules in red cell, 84 Adipose tissue in bone, 197, 198 Adrenal cortex, 244 Adsorptoid function of lymphocytes, 141 Adventitial cell, 250, 273, 274, 279, 306, 317 Age, changes with, in blood cells, 148, 151, 174, 191, 205 Agglutinins in bone-marrow, 52 Aldehyde reaction, 251 Allomorphism, 286 Alterations of resistance, 75 — of shape, 91 — of size, gr (red cells) Altmarm-Schridde granules, 32, 49, 125, 274 Amidine grouping, 241, 279 Amitosis in blood cells, 128, r36, 151, 177. i8r, 214, 229, 256, 268, 271 Amoeboid movement of blooid ceUs, 141, 183, Z13 of megakaryocytes, 49 nature of, 221 Amphochromophile myeloblasts in reptiles, II Amphochromophflic change, 174 Anaplasia, 14, 245, 257, 310 — discussion of, 17, 38 — expressed graphically, 39 — versus metaplasia, 290 Ancestral memories of cell, 302 Ancestry of plasma cell, 272 Angioblast, 53, 57 An&ocytosis, 92 Anisotonia of serum, 66 Anthrax, eosinophiles in, 255 — spleen in, 299 Anti-auxetics, 192 Anti-bodies, formation of, 86 — in spleen, 192 Antitoxic function of lymphocytes, 154 Aplasia, 100, 104 Area vasculosa, 54 Arginase in lymphoctyes, 142 Arguments relating to dualism, 30 existence of primordial cell, 25-29 infective theory of leukaemia, 41 leuk£Bmia and sarcoma, 42 lipoid film over red cell, 72 myeloid metaplasia, 301 neutrophile granule, 221 primordial cell, 27 source of eosinophiles, 256 unitarianism, 33 {See also under Theories.) Artificial production of aplasia in bone- marrow, 107 Astrosphere in blood -cells, 133, 151, 176, 187, 204, 260, 268, 270, 271 Atrophic plasma cell, 283 Atrophy of spleen-follicle, 301 Attraction-sphere in primordial cell, 8 Atypical bone-marrow cells, 212 — forms of blood cells, 20, 131, 209, 212 — — eosinophiles, 209 metamyelocytes, 209 mother cells, 20 Auer bodies, 9 Autocytolysins, 74 Auto-isolytic substances in blood, 107 Autolytic changes in bone-marrow, 198, 199 monocytes, 182 (See Degenerative Changes.) — ferments, 142 — substances, 107 Autoparenchymal metaplasia, 303 Auxetic processes, 241 Azur granules, 32, 143, 176, 178, 181, 185, 304, 206 myeloic, 143, 227 origin of, 185, 204 Azurophile polychromatophilia, 78 AzurophiUa, 186 Bacterial action and cytoplasia 291 — substances and neutrophiles, 224 Basement membrane, 25 Basichromatin, 13 Basophile substances in cells, 14 Basophilia, cause of, 274 Basophilic granules in neutrophile, 225 Bastard cells, 212 Beckton granules, 133 Bedside study of an£emia, 106 372 General Index Bilinogea in urine, 75 BiUroth's malignant lymphoma, 310 Birth of large mononuclear leucocyte, 183 — of neutrophUe, 208, 212 — of red cell, 65 Blood cell, formula, 4 factories, 2, 45, in, 156, 195 — dust, 98 — in newly born, 109 — in infants, 236 — in various diseases, see Index to Diseases — - platelets, 70, 85 — supply, of hone, 195 lymph-node, 113 spleen, 119 — tumour cells in, 309 Bone marrow, 105, 254, 278 anaplasia, 310 — — as red-cell factory, 45 as source of lymphocytes, 112 (foot- note), 121 white cells, 195 eosinophiUa of, 252, 256 giant cells, 300 hyperplasia, 314 in megakaryocytomatosis, 306 in erythrsemia, 109 lymphoid cells of, 112 metaplasia, 304, 287 of fowls during hunger, 34 primitive, 56 structure of, 2, 45, 195 Bottcher crystals, 252 Cabot ring bodies, 76, 79, 83 — membranes, 66 Cancer extract and mast cells, 260 — juice, effect on lymphocytes, 153 Capsule body, 70, 85 Carcinoma cells, 145, 186 Caryolysis, 229 Caryorrhexis, 217, 220, 229 Cause of high colour index, 89 Cell constituents of splenic pulp, 161 — counts, ansmia, 92 bone marrow, 51 — couples, 137 — - formula of tissues, 280, 288, 319 abnormal, in birds, 11 — inclusions in primordial cell, 9 — proliferation in testis, 25 Central sinus of lymph gland, 130 Centriole of blood cells, 49, 70, 85, 88, 26 1 Centrosome, 97, 213, 220 Change in hsemoglobin content, 89 — in staining reaction, 13 Charcot-Leyden crystals, 251 Chart of anaemias, 104 — - Arneth's method, 219 — exudate cells, 216 — interrelations between follicle and pulp, 193 — (See also Scheme.) Chemical characters of blood-platelets, 85 cells, II neutrophiles, 222 — composition of lymph-node, 142 Chemistry of eosinophile granule, 251 — erythroblast, 62 — lymphocyte, 141 — phenolphilic substance, 166 — large mononuclear leucocyte, 184 — normoblast, 64 — red cell, 72 Chemotaxis, 31, 221 Chondriosome, 145 Chromatin, metaplasia of, 153 Chromatolysis, 65 Chromidial bodies, 9 — fragments, 79 Chromidium, 85 ChromoUnin granules, 83 Chromosomes, 13 Ciliated cells in spleen, 161 Clasmatocyte, 261, 264, 267, 274, 277, 278, 303 Classification of anaemias, loi, 105 — blood-cells, 5 — large mononuclear cells, 179 — lymphoid elements of blood-stream, 131 — lymphosarcoma, 310 — myeloic cells, 132 — neutrophiles, 217 — plasma cells, 267 — system diseases of blood-forming organs, 31S — (See also Table.) Clinical diagnosis from study of blood- films, 233, 309 — evidences of regeneration, 106 — significance of punctate basophilia, 81 — study of anasmia, 106 Colloidal action in metaplasia, 287 — character of red cell, 72 hyperchromia, 89 Colloids in spleen, 160 Comparative cytology, 9, 92, 94, 145, 186, 257, 265, 275 (See also Special Index of References TO Animals, or under appropriate blood-cell.l Comparison of Schridde with azur granule, 144 Connective-tissue spaces, 150 Contour of cell (see Morphology) Contrast between leukaemia and leucocy- tosis 240 — (See also Table) Couples of cells, 137 Cryptogenetic agents, 307 — infections, 291 Curvilinear character of cytoplasia, 153 CycUcal character of progress of haemopoiesis 14 — change in lymph follicle, 115 Cytology, laws of, 18 Cytolysis, 132 Cytolytic forms, 24 Cytometaplasia, 37, 148, 152, 282 Cytometaplastic processes, 30 Cytoplasias, 30, 37, 148, 152, 153, 188, 191, 233, 278, 284 — curvilinear character of, 153 General Index 373 Dark-ground iUumination, eosinophile, 251 neutrophile, 214 red cell, 72, 82, 145 Date of formation of blood cells, 55, 59 bone-marrow, 56 (footnote) Daughter myelocyte, 283 — plasma cell, 267 Death of leucocyte, 228, 229 — of primordial cell, 23 Defects of ordinary cell-count, 5 Degenerate spermatozoa, 233 Degenerative changes in lymphocyte, 264 bone-marrow, 199 myelocyte, 208 — • — plasma cell, 276 red cell, 73 -i spleen, 103 — character of sudanophile leucocyte, 227 neutrophile granule, 225 — forms of large mononuclear leucocyte, 179 lymphocyte, 137 plasma cell, 268 pulpar cell, 190 Demilune body, 88 Development of lymph nodes, 130 Deviation to the left, 106, 197, 217, 218, 238 Diazin green, 70 Diflerence between haemopoietic tissue and organ, 6 (footnote) Differential diagnosis of leucoblast, 205 lymphocyte, 135-137 lymphoidocyte, 20 megakaryocyte, 49 monocyte, 175, 176, 178, 179 neutrophile, 229 normoblast, 64 plasma cell, 272, 269 polychromatophilia, 78 — — transitional cell, 178 Differentiation, discussion of, 16 — signs of, 18 Digestion lyrnphocytosis, 142 — lymph follicle during, 115 — Malpighian body during, 120 — spleen during, 161 — sudanophile leucocyte in, 227 — leucocytosis, 140, 235 Diplococci, action on leucocytes, 229 Discoplasm, 82 Discussion of cell-descent, 38 Drugs, effects, 78, 79, 109, 147, 169, 236 anaesthetics, 236 antitoxic sera, 236 atropine, 239 auxetics, 24r benzol, r49, 239 blood poisons, 207 camphor, 236 cinnamate of soda, 236 colchicin, 38, 260 coUargol, 236 digitalis, 236 digitoxin, 237 ethereal oils, 236 hydatid fluid, 253 hydroxylamine, 22 r mesothorium, 104 nitrobenzol, 3S Drugs, effects, nucleinic acid, 236 organ extracts, 236 peptone, 239 pilocarpine, 253 potassium chlorate, 236 pyrodin, 260 pyrogallol, 236 quinine, 236, 239 phenylhydrazin, 82 radium, 99 saponin, 82, 221 on bone marrow, 52 thorium X, 239 toxins, 36, 239 • — • — turpentine, 236 trypsin, 239 tuberculin, 253, 260 ■ ;i;-rays (q.v.) on large mononuclears, r84 on lymphocyte, 139 on myelocytes, 207 on spleen, 300 -on tissue eosinophiles, 255 — leucoblastic action of 147, 169 Dualism, 29, 30 Duration of life of leucocyte, 229 of lymphocyte, 148 — — of plasma cell, 275 — ■ — of primordial cell, 20 Dwarf cells, 20, 134, 136, 212 — lymphocyte, 134, 136 — lymphoidocyte, 20, 136 — myelocyte, 134 — promyelocyte, 134 Dysmorphism, 286 Effect of hunger on bone-marrow, 34 — short-circuiting thoracic duct, 33 Elastic fibrils in spleen, 161 Embryology, bearing on existence of pri- mordial cell, 28 — of myeloid and lymphatic elements, 31 Embryonization, 63, 81, 310 Endothelial cell, 56, 115, 161, 173, 274, 283 isomorphism of, 56 — hyperplasia, 307 — theory of large mononuclear cell, 181 Endothelioid cells, 173, 191, 278 in germ centre, 306 Enterokinase, source of, 167 Eosinoid cell, 250, 317 — change, 154, 282 Eosinopenia, 239, 256 Eosinophile cell, r93, 209, 247, 249, 64, 283, 305, 316, 317 functions, 253 granules of, 14, 251 in bone marrow, 202 in hs3molymph gland, 170 in spleen, 121, r6o morphology, 249 normal percentage, 4 source, theories, 252 varieties, 249 — lymphosarcoma, 310 Eosinophilia, 218, 238, 280 — causes, 253 ■ — scheme, 280 374 General Index Epithelioid cells, 283, 293, 315, 316, 317 Epithelium, metaplasia in, 285 Erythroblastic metaplasia, 310 Erythroblasts, 56 — chemistry of, 62 — discharge of nucleus, 56 Erythrolysis, 170 Erythrophages, 74, 162, 190 Erythropoiesis in chick, 57 — ■ in spleen, 92, 167 Estimate of life of red cell', 73 Evidence of destruction of red cell, 74 Experimental alteration of blood-cell for- mula in birds, 11 — lymphocytosis, r3g Experiments by Werzberg, 35 Extractives of leucocytes, 227 Extrusion of nucleus of red cell, 55 {Fig.) Fabricius, pouch of, 147 Factories of blood cells, 2, 4, 45, in, 156, 195 Fallopian tube, lymphocytes in, 152 Fasting, effect on tissues, 115, 120, 184, 201 — {See Hunger, Starvation.) Fat, absorption of, 118 — in lymph nodes, 116, 118, 184 Fate of leucoblast, 205 — lymphocyte, 148, 154 — myelocyte, 207 — plasma cell, 275 — primordial cell, 15 — red cell, 73 Ferments in leucocytes, 223, 227 — lymphocytes, 144 Fibrinogen, seat of formation, 52 Fibroblastic plasma cell, 267, 283 Fibroblasts, 193, 245, 247, 283, 293, 308, 315, 316, 317 Fixed connective tissue cell, developmental sequence, 30 Flemming bodies, 132 Foam cell, 283 Follicle, Malpighian, 120, 174 — of intestine, 274 — of spleen, 274 — plasma cells round, 273 Foreign body giant cell, 278, 283 Formation of bone-marrow in embryo, 55 — in lymph-node, 50 — of hsemoglobin, 58 — of red cells in spleen, 59 Formative marrow, 45 Formula, blood-cell, 4 > — cell, of tissues, 280, 288, 319 Fraenkel-Much granules, 309 Fuchsinophile granules, 206 Functions of bone-marrow, 52 — eosiuophile, 253 — large mononuolear leucocyte, 183 — leucocyte, 238 — lymphocyte, 137 — lymph-nodes, 118 — myelocyte, 207 — neutrophiles, 221 — oxydase granules in neutrophiles, 227 — plasma cell, 275 — spleen, 167 Ganglion cells in spleen, 161 Gelatinous degeneration of bone-marrow, 199, 288 Genealogy of erythrocyte, 97 (birds) GentianophUe granules, 270, 272 Germ-centre cells, 124, 127, 115 endothelioid cells in, 306 locular arrangement in, 129 Giant cells, 46, 48, 59, 161, 250, 278, 283, 292 in bone-marrow, 48 in spleen, 59, 161 — leucocyte, 134, 212, 229 — large mononuclear cell, 178 — nuclei, 306 Gigantocyte, 91 Glass body, 70, 88 Glossary, reference to, 5 Glycogen granules in eosinophile, 252 — reaction, 226 Goblet cell, 152 Granoplasm, 223, 272 Granular cell of marrow, 46 Granules, 229, 270, 312 — acid, in red cell, 84 — Altmann, 274 — azur, 144, 185 — basophiUc in neutrophUe, 225 — Beckton, 133 — fuchsinophile, 206, 309 — gentianophile, 270, 272 — glycogen, 252 — mast, 263 — monocyte, 144, 185 — neutrophilic, 185, 213, 221 — phenolphUio, 166 — of leucocytes, 213, 232 — of plasma cell, 271 — of red cell, 84 Granulomatosis, 315 Granulosarcoma, 288 Graphic record of bone-marrow cytology, 196 — representation of Arneth's system, 215 H^MAL lymph glands, 170 Haemoblast, 54, 58 — metaplasia in, 294 Haemoglobin, formation of, 65 — mechanism of formation, 62 — percentage of, 4 — synthesis, 294 Heemokonia, 85, 98 Hasmolymph glands (nodes) 102, 168, 170, 254 types, 169 functions, 170 Hiemolysis in spleen, 162 Hsemo- versus spermogenesis, 27 Head kidney, 169 Heinz bodies, 82 Heteroplasia, 286 Histology of bone-marrow, 46 Histolysis of red cells in spleen, 74 Hodara plasma cell, 250 Hormone for bone-marrow, 201 Horse serum, 239 Hourly rate of cell multipUcation, 51 Hunger, effect of on bone-marrow of fowls, 34 General Index 375 Hunger, lymph-node in, 117 — (See Fasting, Starvation.) Hyaline ceU, 5, 137, 174 — leucocyte, 5 Hybrid cell, 134, 212, 251, 250 — mast cell, 252, 261, 264 Hyperchromia, 89 Hyperhypolymphocytosis, 138 Hyperleucocytosis, 236, 237 Hypermetaplasia, 154 Hjnpernomic secretion, 142 Hyperplasia, discussion of, 39, 289 — versus metaplasia, 289 Hyperplastic bone-marrow, 109 — processes in leucopoietic tissue, 239 Indeterminate cells, 45 Indifferent cells, 45 — marrow cells, 205 Infant, blood in, 236 Infective character of leukaemia, 41 — ■ granuloma, 309 Immunization, effect on bone-marrow, 52 Immunity, relation of spleen to, 167 Inanition [see Starvation) Innenkorper, 82 Irmer structure of cells {see Morphology) Internal secretions and bone-marrow, 52 Interfollicular cell, 193 — ground tissue, 304 — sinus of lymph gland, 113 — tissue, 316, 317 Intestinal mucosa, eosinophiles in, 252 — epithelial cell of salamander, 13 Intestine a source of lymphocytes, 140 Ionic concentration, 160 lodophilia, 226 lodophilic granule, 225 Iron in plasma cell, 272 Irritation cells, 24, 179, 188, 247, 266 (See Plasma Cells.) Jolly body, 66, 79, 82, 83, 84, 107 Juvenile large mononuclear cell, 190 — lymphocyte, 136 Karyolysis, 65 Klein-Gumprecht shadows, 24, 132, 148, 268 Krompecher plasma mast cell, 271, 283 Kundrat's lymphosarcomatosis, 312 Kurlofi bodies, 144, 176, 177, 181, 182 Large lymphocyte, meaning of term, 5, 127, 283 — mononuclear leucocyte, 134, 153, 171 drawing of, 190, 193 ' fate, 188 functions, 183 increase of in blood, 218 normal percentage, 4 — mononucleosis (see Monocytosis), 218 Laws of cytology, 18 Leucoblast, 20, 21, 48, 112, 132, 134, 178, 179, 193, 203 Leucoblastic cells, 250 — line of development, 209 Leucocyte (see Neutrophile) — death of, 228 Leucocyte, duration of life, 229 Leucolytic substances, 236 Leucocytoid cell, 132, 134, 135, 179, 193, 316, 317 — lymphocyte, 20 — macrolymphocyte, 20 — microlymphocyte, 283 Leucocytolysis, 230, 239 — determination of, 230 Leucocytophages, 237 Leucocytosis, 14, 52, 233-238 — phases of, 237, 238 — significance of, 235 Leucomonocyte, 250 Leucopenia, 14, 235, 238 — ■ drugs causing (see Drugs) Leucosarcoma cell, 20, 22, 23, 134, 316 Leukaemia (see Index of Diseases) Leukaemic mast cell, 264, 265 — monocytoid leucoblast, 193 Leukeemoid effects of colchicin, 38 Lienolymphatic system, 314 Life history of red cell, 69 Linin, 19 Lipase in large mononuclear leucocyte, 185 — in lymphocyte, 142 Lipoid granules in large mononuclear leucocyte, 186 Lipoids in eosinophile granule, 252 — plasma cell, 272 Lipolysis, 167 Lipolytic ferments in blood cells, 81, 164 — toxins on red cells, 81 Lipoferous leucocytes, 226 Liver, erythropoiesis, 55 — ■ red cell formation in, 56 Local eosinophilia, theories, 256 (see under Eosinophile) Locular arrangement of germ-centres, 129 Loss of nucleus of erythroblasts, 56 Lowit's bodies, 9 Lymphadenoid cell, in — hyperplasia, 304 — marrow, 102 — tissue, 293 Lymphaemic lymphocyte, 193 — microlymphocyte, 20 Lymphatic plasma cell, 267 — system, structure of, 3 Lympherythroblast, 30 Lymph follicle, cyclical changes in, 115 — nodes, 60, 278, 301 blood supply, 113 development from adipose tissue, 118, 130 effect of toxins, 118 functions, 118 in hunger, 117 purins in, 117 red cell formation in, 60 regressive changes in, 118, 130 structure, 3TI Lymphoblast, 32, 57, 125, 132, 164, 191, 271 — differential diagnosis, 32, 178, 191 — function, 164 — morphology, 125 — versus myeloblast, 32 Lymphoblastic cells, 247, 250 376 General Index Lymphoblastic cells, line of development, 124, 126 macrolymphocyte, 20, 21, 124, 179, 191. 193 monocyte, formation of, 162 Lymphocyte, 56, 57 — chemistry, 141 — definition, 11 1 — differential diagnosis, 135 — functions, 137 — in intestinal waU, 140 — in puncture fluid, 139 — in spleen pulp, 160 — in starvation, 140 — made in bone-marrow, 112 (footnote) — ■ morphology, 132 — normal percentage, 4 — nutrioid function, 139 — .of blood-stream, 131, 134 — of chronic lymphatic leukaemia, 133 — of foUicle, 190 — of tissue, I3r, 150 — relation to thrombocyte, 153 — with reniform nucleus, 135 Lymphocytoid cell, in — large mononuclear cell, 178 Lymphocytoma, 274 Lymphocytosis, 33, 138, 153, 218, 235 — causes, 138 — varieties, 138, 153 Lymphogenesis, scheme, 126 Lymphogranulomatosis, 302 Lymphoid elements of blood stream, classi- fication of, 131 — erythroblast, 46, 55 {Fig.), 60 morphology, 60 — follicle, 114 — hasmoblast, 20, 76, 134, 136, 195 — metaplasia, 303 Lymphoidocyte, 8, ri, 15, 47, 112, 134, 190, 193, 203, 247, 283 — azur granules, 32 — chemical characters, 11 — comparative cytology, fate, 15 — morphology, 8 — phases in life of, 15 Lympholeucocyte, 174, 187, 190 — comparative cytology, 187 Lymphoma, 273 Lymphoma cell, 193 — paramyeloid, 304 — perivascular, 122, 123, 154 function of, 123 Lymphomatosis, scheme, 281 Lymphopenia, 138, 139, 218, 239 — causes, 139 Lymphophilia, 238 Lymphopoiesis, accessory factories, 122 Lymphoprimitive cell, 192, 283 Macrocytase, 162, 183, 184 Macrocyte, 76, 91 Macroleucoblast, 250 Macrolymphocytar metaplasia, 304 Macrolymphocyte, 30, 117, 125, 132, 134, 137, 179, 283, 316, 317 — developmental sequence, 30 Macrolymphoidocyte, 203 Macromydoblast, 316, 317 Macronormoblast, 76 Macrophage, 66, 119, 120, 171, 190, 229 — in bone-marrow, 66 Macroplasma cell, 160 Malachite green on lymphocyte, 142. Malarial red cell, 70 Malpighian body, 3, 120, 161, 308 — follicle, 3, 120, 161, 308 Marchand cell, 171, 173, 250, 283 Marrow leucocyte, 45 Marrow lymph gland, 169 Marchalko cell, 250, 267, 274 Martinotti's pseudoplasma cell, 283 Massage, effect on lymphoctyes, 152 Mast cell, 4, 14, 19, 57, I53. 160, 193, 229, 247, 250, 251, 259, 260, 261, 262, 264, 283, 293, 307, 316 change, 19, 133, 307 chemistry, 251 function, 262 granules, 14, 229, 251, 262 metaplasia, 19, 153, 307 morphology, 260, 261 myelocyte, 260 normal percentage, 4 — ■ — table, 259 transformation {see Metaplasia) varieties, 259, 264 Maurer-Schiiffner punctation, 84 May-Giemsa stain, 62 Meaning of " diseases of blood," 6 Mechanism of extrusion of red cell nucleus, 65 — formation of haemoglobin, 62 — metaplasia, 293 Megakaryocytes, 45, 48, 49, 50, 87, 98, 161, 162, 193, 192, 201, 215, 250, 278, 283, 300, 305, 306, 312, 316, 317 — differential diagnosis, 49 — during digestion, 162 — functions, 49 — in bone-marrow, 201 — in liver, 58 — in spleen, 192 — in lymph nodes, 305 — occurrence, 49 — relation to himogenesis, 49 — significance, 49 — theories concerning, 50 Megakaryocytomatotic metaplasia, 305 Megaloblast, 46, 55, 62, 63, 76 — differential diagnosis, 63 — figure, 55 — forms, 62 — views as to nature, 63 Megaloblastic degeneration, 63 Meristem formation of red cells, 52 Meristematic proliferation, 15 Merozoites, 15 Mesenteric lymph nodes,- 184 Mesolymphocyte, 128, 134, 135, 147, 193, 250, 283, 317 Mesoleucoblast, 204 Mesenchymal cells, 130, 283, 312 — tissue, 130, 186 in invertebrates, 186 General Index 377 Metabolic changes in blood cells, 13 boue-marrow, 198 lymph nodes, 117 Metabolism in bone-marrow cells, 199 — spleen, 162 Metachromatin, 13, 263 — of granules, 229 Metahyperplasia, 100, 108 Metahyperplastic character of leukasmia, 4r Metamyelocyte, 134, 178, 190, 208, 209 — tjTjical forms, 209 Metaplasia, 23, 39, 52, 64, roo, 104, 108, 153. 169, 173, 201, 228, 239, 285, 289, 290, 293, 297, 298, 302, 303, . 304, 305, 307, 308, 310, 311 — curvilmear character, 153 — definition, 285 — discussion, 285, 31 r — erythroblastic, 310 — exciting agents, 297 — expressed graphically, 39 — in bone-marrow, 52 — lymphoid, 303 — macrolymphycotar, 304 — mast cell, 307 — mechanism, 293 — megakaryocytomatotic, 305 — microlymphocytar, 304 — of cells, 228 — of plasma cell, 307 — sarcoid, 23, 308 — special examples, list of, 298 — splenoid, 109, 308 — versus anaplasia, 290 degeneration, 289 h3rperplasia, 289 Metaplastic processes in leucopoietic tissue, 239 Metastatic nature of myeloid transformation, 302 Methylene blue -picric acid stain, 66, 70, 76 Methyl-green-pyronin, 32, 79, 84 Methyl-green-Giemsa-aurangeate, 13 Metrocyte, 61 Michaelis' spherinucleate cell, 283 Microcyte, 76, 82, gr Microleucoblast, 250 Microlymphocytar metaplasia, 304, 305 Microlymphocyte, 135, 193, 250, 316, 317 {See also Lymphocyte) Microlymphoidocyte, 9, 20, 193, 203, 283 Micromyeloblast, 105, 132, 273, 280, 316, 317 Micromyelocyte, rgs, 208 Micropromyelocyte, 206 Middle zone of lymphocyte, 133 Migratotaxic substances, 282 Miniature large mononuclear, 178 Mitochromes, 97 Mitosis of mast cell, 26r — of neutrophiles, 220 Monocyte, 5, 131, 132, 134, 144, 172, 173, 185, 187 — granulation, 144, 185 — in animals, 187 Monocytoid macrophage, xgs, 253 Monocytopoiesis, 167 Monocytosis, 182, 184, 238 Monopenia, 139, 184 Monophyletism, 29, 30 Morphology of blood platelets, 85 — endothelial cell, 18 r — eosinophile cell, 249 — large lymphocyte, 127 — large mononuclear leucocyte, 176 — leucoblast, ar, 203 — lymphoblast, 32, 125 — • lymphoblastic macrolymphocyte, 21 — lymphocyte, 132 — lymphoid erythroblast, 60 — lymphoidocyte, 8, 21 — mast cell, 251, 260 — megakaryocyte, 48 — • megaloblast, 61 — mesolymphocyte, 128 — monocyte, 174 — myeloblast, 32, 205 — myelocyte, 207 — myeloic cell, 203 — neutrophile leucocyte, 213 — normoblast, 64 — plasma cell, 267 — primordial cell, 8 — pulpar cell, 189 — red cell, 69, 74 — Rieder cell, 22 — Schridde-Hodara cell, 27r — spindle cell, 97 — tissue lymphoctye, 127, 150 Mother cell, 175, 189 MultipotentiaUty of cells, rgr, 288 — of pulpar cell, igr Muscular exertion, effect of, on lymphocytes, 149 Myelaemic microlymphoidoctye, 20 Myeloblast, 205, 3r7 Myelocyte, 56, 134, 207, 300 Myeloic azur granulation, 143, I5r, 206, 227 Myeloic cells, 132, 154 list of, r32 — plasma cell, 267 — pseudolymphocyte, 179 Myeloid metaplasia, 33, 36, 41, 52, 167, i6q, 173, 186, 192, 2or, 298, 300 nature of, 300 in pernicious anaemia, 4r (and see under names of diseases) in birds, 186 — tissue, 3r, 33 action of infective fevers on, 33 — transformation (see Myeloid Meta- plasia) Myeloleucocyte, 57 Myelolymphocyte, 21 Myelolymphoidocyte, 125, 134, 136, 179 Myelopathy, loi Myelopotential cell, 303 Myelotoxic sera, 301 Myelotoxins, 35 Myogenic leucocytosis, 152, 236 Nerve fibrils in spleen, 161 Neutropenia, 239 Neutrophile leucocyte, chemical characters, 222 death of, 228 378 General Index Neutrophile leucocyte, differential diagnosis, 231 duration of life, 229 function, 221 granules, 222, 145 morphology, 213 uninucleate, 316 — pseudolymphocyte, 136 Neutrophilia, table of, 237 Nile blue, 71, 75, 82, 85 Nomenclature, variation of, 5 (and see Glossary) Nongranular cells of marrow, 47 Normal process of extrusion of normoblast nucleus, 66 Normoblast, 161 — figure, 55 — chemistry, 64 — differential diagnosis, 64 — morphology, 64 — nucleolus, 64 Normoplasia, 286 Nuclear origin of mast granule, 263 Nucleases, 142 Nucleinic degeneration, 163 Nucleoid, 386 Nucleolus (see Morphology of Respective Cells) — fate, 60 — in megaloblasts, 61 Nucleophage, 190 Nucleus (see under Morphology of Respec- tive Cells) Objections to Arneth's theory, 216 (see also Theories) Old age of cell, 15 signs of, in cell, 18, 144, 15T Ontogenetic development, signs of (see Old Age) Origin of tissue-eosinophiles, 256 Orthochromatic megaloblast, 61, 62 Orth's leukaemic lymphadenoma, 310 Osmotic action, 67, 73, 91, 210, 222, 229 in extrusion of nucleus, 67 on myelocyte, 229 on neutrophile, 222 of phagocytosis, 210 in red cell, 73 Osteoclast, 48, 56 Outer form of cell (see Morphology) Oxydase, 32, 73, 163, 164, 185, 200, 227, 251 — granules, 125, r63, 174, 185, 227 — in bone marrow, 251 — in red cell, 31 — in eosinophile, 25 r Oxydase reaction, 31, 35, 61, 176, 185 Oxyphilic granules in neutrophiles, 225 Pachydermia of red cell, 89 Pander's islands, 53 Panoptic stain, 135 ■ method, 135 Parablast, 53 Paramyeloid lymphoma, 304 Paranuclear attraction-sphere (see Mor- phology OF THE Various Cells) Paraplasm (see Morphology) Parenchymal cells, 293 — tissue, 316, 317 Parent cell, 203 Paroxydase, 142 Pathological plasma cell, 267 — process of extrusion of normoblast nucleus, 66 Pathology of leucopenia, 239 Percentage composition of red cell, 73 Perichondrium and haemogenesis, 55 Perifollicular lymph-sinus, 113, 130 Perinuclear zone (see Morphology), 270 of lymphocyte, 151 Periosteum, 286 Perithelial cell, 193, 279, 283 Perithelium, 273 Perivascular lymphoma, 3, 122 — tissue, 247 Phagocytes, 115, 141, 161, 167, 170, 183 Phagocytic properties of marrow cells, 47 Phagocytosis and drugs, 222 Phanerogenetic agents, 307 — infection, 291 Phases of leucocytosis, 237, 238 — in life of primordial cell, 15 Phenolase, 164 Phenolphilia, r63, 253 — of eosinophiles, 251 — of mast granules, 263 Phenolphilic cells, 121 — ■ granule, action of, 166 of leucocyte, 227 in plasma cell, 272 — substance, 163 Phlogocyte, 243, 246, 266 Phlogocytosis, 243 Phlogopoiesis, 246 Phylogenetic development, signs of, 18 Physiological leucocytosis, 236 Pigment cell, 265 Pigmentophages, 47, 179, 183 Plasma cell, 57, 120, 134, r36, r53, 162, 186, 193, 247, 250, 264, 266, 283, 289, 290, 293, 315, 316, 317 change, 20 ■ comparative cytology, 276 degenerative change, 276 duration of life, 275 fate, 275 functions, 275 granules, 27r metaplasia, 307 myeloma, 274 Plasmocytoma, 308 Plasmoid cell, 146, 160, 190, 271, 274, 317 — change, 154, 245, 277, 282 — stimulus, 308 Plasmolysis, 24 Plasmosomes, 144, r76, 224, 225 Plastin matter, 84 Platelets, 132 — in anaemia, 86 Play between parenchymal and stromatic elements, 311 Plumbism, 80 Pneumotoxin, action on myeloid tissue, 36 Poikilocyte, 76 Poikilocytosis, 91 General Index 379 Poisons on blood (see Drugs), log, 147, 169 Polyblast, 154, 273, 283, 293 Polychromatophflia, 77, 78, 204 — difierential diagnosis, 78 — erythroblast, 57 Polychromatic gigantocyte, 76 — megaloblast, 61, 62 Polymorphonuclear leucocyte, normal per- centage, 4 [see Neutrophile) Polynucleosis in intestinal wall, 141 Pouch of Fabricius, 147 Prechromatophore cell, 263 Prespermatogonium, 27 Primitive bone-marrow, 56 — erythroblasts, 54 Primordial blood cell, 5, 7, 8, 15, 23, 131, 175. 179. 189, 201, 278 list of, 132 morphology, 8 fate, 15 death of, 23 phases in life of, 15 Prochromatin, 13 Progress only cydical, 14 Proliferation, meristematic, 15 — of cells in bone-marrow, 51 Promegaloblast, 60 Promyelocyte, 134, 137, 175, 179, 206, 209 Prosoplasia, 286 Protometrocyte of selacia, 33 Proteosomes, 224 Pseudo-eosinophUe cell, 250 Pseudolymphocyte, 136, 283 Pseudoplasma cell, 121 Pulp cord, 114, 157 — tissue {see Pulpar Tissue) Pulpar cell, 158, 188, 189, 190, 193 — tissue, 4, 113, 114, 156, 157, 158, 186, 274, 300, 312 in myeloid metaplasia, 300 in teleostean fish, 186 relation to venous channels, 158 Pulpocyte, 172 Punctate basophilia, 67, 71, 76, 77, 78, 79, 84, 107 Puncture fluid, lymphocytes in, 139 Purinic degeneration, 163 Purins, 117, 229 Pus cells, 229 Pycnosis of nucleus, 64, 200 Pycnotic megaloblast, 63 — nucleus, 200 Pyrrhol cell, 283 reaction, 251 Radium therapy, 99 Red blood-cell, 44 acid granules in, 84 alterations of shape, 91 of size, 91 of resistance, 75 birth of, 65 chemistry, 72 counts in animals, 96 fate, 73 formation in liver, 56 in lymph-node, 60 in spleen, 59 Red blood-cell, life history, 6g lipoids in, 62 number per c.mm., 4 — cell shadows, 82 Regenerative phase, 238 Regressive changes in lymph node, 118 Relative leucocytosis, 237 Reserve factories of blood-cells, 3 Resistance of red cells, 73 Reticular substance of red cell, 75, 177 Reticulum of lymph-node, 115 Reversible reaction, 16 Ribbert's lymphocytoma, 310 — - lymphoma, 112, 122, 168, 273 Rieder cell, 20, 22, 132, r34, 136, 179, 193, 203, 283, 3r6 Rules for studying auEemia, lto6 leucocytosis, 234-238 Russell bodies, 276 Sarcoid blastomatosis, 309 — metaplasia, 23, 308 Sarcoma cell, 113, 145, 167, 270 — injection of, 167 Sarcomatosis, 308 Scene of action in blood-forming tissues, 159, 196, 279 Scheme of development of neutrophile, 2ro, 211 — effect of plastic irritation, 275 — embryonic erythropoiesis, 57 — enlargement of lymph-glands, 316 -of spleen, 317 — eosinophilia, 280 — erythropoiesis, 68 — inter-relations between phlogocytes, 283 — lymphogenesis, 126 — fate of lymphocyte, 154 of plasma cell, 276 — lymphomatosis, 281 — monocytes, 174 Schridde granule, 133, 144, 145 comparison with azur granule, 144 Schridde-Hodara plasma cell, 193, 267, 271, 274, 283 Schizocyte, 89 Sclerosis of spongioplasm, 274 Seasonal periodicity of red cell formation, 94 Secondary erythroblasts, 62 Secretory character of neutrophile granule, 223 — vacuoles, 177 Senile change of myelocyte, 207 — leucoblast, 193, 283 — l5Tiiphoidocyte, 20 Sera, myelotoxic, 3or Sertoli cell, 15, 26, 51 Shape of cells {see Morphology) Significance of basophilia, 81 — blood film, 90 — iodophiUa, 226 — leucocytosis, 235 — macrocytes, 92 — mast cell granules, 14 — polychromatophiUa, 78 — small round-celled infiltration, 288 — tissue eosinophile, 255 Signs of death of leucocyte, 229 380 General Index Signs of ontogenetic development,' i8 {see also under Fate, Degenerative Changes) Sinus, central, ii8 Sinuses in lymph glands, 113 Sinusoids in liver, 58 Small-round-celled infiltration, 151, 244, 288 ■ significance of, 288 Soterocyte, 86 Source of eosinophile granule, 252 of tissue, 255 — ■ — of mast granule, 263 Spaces, connective tissue, 150 Specific granules, 32 Spermacytoma versus myeloblastoma, etc., 28 Spermatids, 26 Spermatocytes, 26 Spermatogenesis, 25, 37 Spermatogonia, 25, 27 Spindle cell, 96 Spirochete and Kurloff bodies, 177 Spleen, 119, 267, 278, 301 — blood supply, 119 — date of erythropoiesis, 55 — effect of severe injury, 138 — follicle, 274 — histolysis of red cells in, 74 — lymphoid cells, 112 — myeloid metaplasia, 299 — plasma cells in, 273 — pulp in myeloid metaplasia, 300 — red cell formation in, 59 — structure of, 3, iig, 1S7, 311 — syncytial formation in, 157 Splenocyte, 172, 189, 271, 304, 316 Splenoid metaplasia, 169, 308 Splenomonocyte, 173 Splenotoxins, 35 Spongioplasm {see Morphology) Spongioplasmatic cells, 112 Staining by thiazin, 147 — method, for Schilling's modification of Arneth, 217 Pappenheim, 135 — reaction of tingible bodies, 117 Starvation, blood ia, 150, 184, 253 — bone-marrow in, 199 Stereochemistry and metaplasia, 291 Sternberg leucosarcoma cell, 22 Streptococci and ceU-count, 38 — and eosinophHes, 255 Stroma of red cells, 71 Stromatic cells, 48, 161, 193, 278, 293, 305, 309, 312, 316, 317 of bone marrow, 48 reaction by, 309 — tissue, 316, 317 Substantia granulo-filamentosa, 71, 84 — ■ reticulosa, 62 Sudanophilic granule of neutrophile, 226 Surface tension and leucocyte, 209, 221 Syncytial character of marrow cells, 26 of testicular cells, 27 — formation, 158 System, lieno-lymphatic, 314 System-diseases of blood, table of, 319 Table of Arneth's system, 215 — blood cells, 211 • plasma cells, 269 — changes in white cell count, 234 — cells pathological to blood, 211 — comparison of vital stainable substance and basophilia, 81 — contrast between genetic relations of monocyte, 180 granules in lymphoid cells, 175 large mononuclear leucocyte and lymphocyte, 180 lymphoidocyte and leucoblast, 21 leucooytosis and leukffimia, 240 monocytes, 175 myeloic mother ceUs and lymphatic mother cells, 21 myeloid and lymphatic cells, 31 — genetic relations between monocytes, 180 — granules in lymphoid cells, 175 — enlargement of lymph-glands, 316 of spleen, 317 — forms of neutrophilia, 237 — granular structures in red cells, 83 — granules in lymphoid cells, 175 — mast cells, 259 — of theories of origin of large mono- nuclear cells, 179 — plasma cell versus connective tissue cell, 272 — 267, 268 — showing modes of extrusion of normo- blast nucleus, 81 views about extrusion of normoblast nucleus, 67 Testis, cell-proliferation in, 25 Theatre of action, 157, 196 Theories about nature of azur granulation, r44, 180, 185 germ-centre cell, r24 Kurloff bodies, 177 large mononuclear leucocyte, 180 megaloblast, 67 megakaryocyte, 50 myeloid metaplasia, 30T neutrophile granulation, 222 pernicious anemia, 103 origin of blood-platelets, 86 eosinophile, 252 large mononuclear leucocyte, 179 mast granule, 263 megakaryocyte, 50 plasma cell, 272 spindle cell, 98 tissue eosinophile, 256 significance of polychromatophilia, 78 Thiazia, 147 Thoracic duct a source of lymphocytes, 140 Thrombocytes, 57 — relation to lymphocyte, 153 (footnote) Thymic state, 154 Thymocyte, 112 Thymus, 112, 254 — myeloid metaplasia in, 299 Tigroid patches in megakaryocytes, 49 eosinophile, 250 Tingible bodies, ri7, 148 Tissue, cell-formula, 280, 288, 319 General Index 381 Tissue change in myeloid metaplasia, 300 — eosinophilia, 254 meaning of, 255 — eosinophile, source of, 255 — lymphocyte, 247, 250, 283 — mast cell, 260 — plasma cell, morphology, 270 Tonsil, 112, 152, 267, 286 — plasma cells in, 275 Toxins and leucocytosis, 239 — effect on bone-marrow, 52, 102, 108 lymph nodes, 118 lymphocytes, 153 — long continued, effect on bone-marrow, 52 Toxoids, action on blood-forming tissues, 43. 288 Transitional cell, 131, 171, 174, 178, 188, 190, 193, 283 Transition from leukaemia to sarcoma, 306 — forms, discussion of, 18 Transplantable leukaemia of hens, 35 Triacid stain, discussion of, 18 Trypsinogenic function of spleen, 167 Trypanosomes and Kurloff bodies, 177 Tryptic systems in spleen, 165 Tumour cells in blood, 309 differential diagnosis, 137 Tiirk cell, 63, 266 Typhoid toxin and eosinophiles, 255 Ultramicroscope, blood-cells in, 133, 145, 220 Ultraviolet light on blood-cells, 61, 71, 133, 144, r45, 177, 178, 220 Uninucleate neutrophile, 316 Unitarian view, 180 Unitarianism, 29 — graphic account of, 30 Unna daughter plasma cell, 283 — plasma cell, 267 Vaccine, smaU-pox, effect on lymphocytes, 154 Vacuolar structures in primordial cell, 9 Vacuoles in primordial cell, 24 Value of blood film, 233 Variants of large mononuclear cell, 178 {see also Atypical Cells) Venous channels, relation to pulpar tissue, 158 Villus, plasma cells in, 275 Vital staining, 62, 72, 73, 144, 207, 220. 223, 278 of azur granules, 144 neutrophile, 220 myelocyte, 207 red cell, 62, 72, 75 Wandering cells, 130, 171, 191, 192, 278,. 283, 293 Wheel structure of nucleus, 62 chemistry of, 62 White cells, number in normal blood, 4 White thrombi, 86 Winkler-Schultze granules, 61, 176, 185 in blood-platelets, 85 in red cell, 69 X-rays action, 104, 236, 245, 282, 314, 305 — on bone-marrow, 201 Yolk-sac, hsemogenesis in, 53 1 ZiNOWSKi's equation, 74 382 INDEX OF DISEASES REFERRED TO IN THIS VOLUME. [Figures in thick type indicate main references. Figures marked with a (*) indicate a reference to blood-cells ; those marked with a (t) refer to tissue-cells, and those not marked at all are references to histopathology.j Abscess, hepatic, 184* Acromegaly, 260* Acute heemorrhagic macrolymphocytar leukagmia, 60 — infections, 138, 163, 169, 184, 208, 217 action on spleen, 163 hsemolymph glands in, 169 large mononuclears in, 184 — leuksemia, 24, 35, 38 — sublymphffimia, 307 {see also under Leukemia) — yellow atrophy, 236* Addison's disease, anaemia in, 109 Agonic conditions, 218* Aleukffimia, discussion of, 4T, 107, 108, 281, 314-318 Aleukaemic lymphadenomatosis, discussion of, 23 Ansemia, 41, 64, 76*, 78*. 79*, 83*, 86*, 90, 92, 100, 101, 102, 103, 104, 105, 106, 184*, 199 (spleen), 208* {see also Pernicious Anemia) — experimental, myeloid metaplasia in, 299 — pseudoleuksemica infantum, 83* Aneurysm, bone-marrow in, 50 Ankylostomiasis, 218* Aplastic anaemia, 79, loi, 102, 103, 105, 217, 218 Appendicitis, bone-marrow in, 50, 122*, 217*, 226,t 254t, 262t Asphyxia, 208* Asthma, 253*, 256t Atheroma, spleen in, 119 Bacillus aerogenes capsulatus infection, spleen in, T92 Banti's disease, histopathology, 41, 90, 108, 167, 313, 317 large mononuclear leucocytes in, 184 Blood diseases, 6, 104, 105 Cancer, 41, 78*, 90, 105, 184*, 236*, 253*, 317 — bone-marrow in, 50, r99 — tissues in, 254, 267 — of bone, myeloid metaplasia in, 299 Cardio-vascular disease, 184* Chloroleucosarcoma, 42 Chloroma, 28, 42, 318 Chloromyeloleucosarcomatosis, 318 Chlorosarcomatosis, 22 Chlorosis, 79*, 106, 138, 217, 253* Cholera, 260 Chorea, 109 Chronic deforming arthritis, 287 — diseases, 184* — • nephritis, 109, 318 bone-maiTow in, 50 spleen in, 163 Cirrhosis of liver, 109, i64t, 236*, 253* Cryptogenetic anaemia, 103 Diabetes, 226* — spleen in, 164 Diarrhoea, bone-marrow in, zqg Diphtheria, 86*, 218*, 254* — spleen in, 299 Eclampsia, 318 Eczema, 253* Epilepsy, 253* Epithelioma, 184*, 255t, 261 Erysipelas, spleen in, 299 Erythema multiforme, 26it Erythraemia, bone-marrow in, 109 Gaucher splenomegaly, 41, 307, 317 General paralysis of insane, 262t German measles, 184* Gonorrhcea, 254* Gout, 236*, 254* Granulomatosis, 316, 317 Graves' disease, 122, 138*, 253* Hematic anaemia, loi Haemolytic anasmia, lor — splenomegaly, 317 Haemophilia, 138* Haemophthisic ansmia, 105 Haemorrhage, 236 * Haemoirhagic diseases, haemolymph glands in, 170 Haemotoxic anaemia, 105 Hemicrania, 253* Hepatic abscess, 184* Hodgkin's disease, 41, 142*, 218*, 250, 278t, 291, 292, 305, 306, 307, 310, 313, 316, 317 Hydatid disease, 255* Hyperchromic anemia, 105 Infant, 207*, 236* Infantile splenic anasmia, 108 Index of Diseases 383 Infections, acute, 33, 102, 138*, 208*, 217*, 260*, 270*, 318 bone-marrow in, 50 — chronic, 138*, 226* — experimental tissues in, 299 — mixed, 218* Infective granuloma, 309 Inflammatory conditions, 236* Influenza, 239* V. Jaksch anaemia, 41, 184*, 208,* 317 Kahler's disease, 105 Kala-azar, 41, 239*, 313, 315, 316, 317 Kundrat's lymphosarcoma, 316, 317 Leprosy, 184*, 253* Leucanaemia, 105, 107 Leucosarcoma versus chlororaa, 42 — versus myeloma, 42 Leucosarcomatosis, 22, 40, 309, 316, 317, 318 Leukaemia, 22, 35, 107, 108, 184*, 185*, 218*, 226*, 237*, 239*, 241, 252, 260, 267t, 291, 292, 316, 317 — acute, 24, 35 discussion of, 38 lymphatic, 309 macrolymphocytar, 63, 297 myeloic, 25 5 1 — chronic, 305 lymphatic, 23, 117, 133', 139*, 154, 167, 253 — discussion of, 39 — due to nitrobenzol, 38 — of hen, 35 — hyperplastic character of, 23 — infective character, 41 — lymphatic, 256t — metahyperplastio character of, 41 — modem view of, 41 — myeloid metaplasia, 299 — nature of, 301 — theory of, 313, 314 — versus chloroma and sarcoma, 42 Leukaemic lymphomatosis, 123, 310 Linitis plastica, 275t Liver abscess, 218* Lues (see Syphilis) Lupus, 26it Lymphadenomatosis, 316, 317 Lymphjemia, 184* — acute, 309 Lymphoblastoma, 28, 315 Lymphocytoma, 306, 317 Lymphogranuloma, 255 Lymphomatosis, 281 — blood-forming organs in, 299 — leukaemic, 123, sro Lymphosarcoma, 42, 123, 292, 306, 317 — eosinophile, 310 Malaria, 88, 105, 184*, 239*, 254t, 260*, 270*, 313, 316, 317 Malignant granuloma, 291, 292 Malnutrition, 239* Malta fever, 239* Mania, 208*, 253* Measles, 239*, 253* Melancholia, 253* Menstruation, 86* Miculicz's disease, 122 MoUuscum contagiosum, 255! Morbus maculosus, 105 Myeloblastoma, 28 Myeloid chloroleukaemia, 212* Myeloleuksemia, 212*, 253* Myeloma, 28, 105, 274t Myelopathic anaemia, 105 Myelophthisic ansemia, loi Myelosarcomatosis, 309, 316, 317 Myelotoxic anaemia, 102 Myelotoxicosis, 291 Nephritis, chronic, spleen in, 163 Neurasthenia, 109 Old age, 182*, 267t Osteomalacia, 254* Osteosclerosis, ro6 — bone-marrow in, 304 — myeloid metaplasia in, 299 Facet's disease, 287 Parasites, animal, 253* Paroxysmal haemoglobinuria, 109 Pemphigus, 253* Peritonitis, 217* — spleen in, 299 Pernicious anaemia, 33, 41, 63, 83*, 89*, 104, 105, ro7, 138*, 184*, 208*, 217*, 226*, 239*, 291 Phanerogenetic anemia, 105 Plasmogenic anaemia, 105 Plethora vera, spleen in, 299 Plumbism, 83*, 107 — spleen in, 299 Pneumonia, 218*, 226*, 274t — bone-marrow in, 50 — spleen in, 299 Polycythaemia, 109 — after splenectomy, 168 Polypus of nose, 255t Post-hamorrhagic anaemia, 105 Pregnancy, 208*, 236*, 318 Primary splenomegaly, 317 Protozoan disease, 217*, 218*, 239*, 316, 317 Pseudoleukaemia, 22, 124, 167, 217*, 237*, 292, 305, 307, 318 Psoriasis, 253* Puerperal fever, anaemia of, 105, 217*, — mania, 253' Pyaemia, 226* Rachitic splenomegaly, 317 Rheumatism, 226*, 254t, 318 Rhinophyma, 261 f Rhinoscleroma, 26it Rickets, 138*, r40*, 184*, 208*, 236* — metaplasia in, 287 Rodent ulcer, 25 5 f Rubeola, 184* 226*, 318 384 Index of Diseases Salpingitis, 247t Sarcoleukaemia, 308, 310, 316, 317 Sarcoma, 241 — theory of, 313 Sarcomyeloma, 42 Scarlet fever, 28, 85*, 184*, 253*, 270* myeloid metaplasia in, 299 relation to leulca;mia, 41 Scurvy, 109, 138* Septic infections, 164, 211, 217, 218*, 226*, 236* Septicsemia, 217*, 218* — bone-marrow in, 50 — spleen in, 299 Shock, 237* Skin diseases, 254! Small-pox, 184* — spleen in, 299 Splenectomy, 109, 138*, 140*, 157, 167, 168, 172 Splenic ansemia, 105 infantile, 108 — new growth, 217 Splenomegaly, 184*, 318 Sporotrichosis, 254* Spring catarrh, 254! Status lymphaticus, 122* Sternberg's anomalous tuberculosis, 316, 317 Subleukaemia, 108 Suppurative processes, 226*, 254* Syphilis, 79, 90, 138*, 2o8*,2i7*, 313, 316, 317 — congenital, 253*, 299 — metaplasia in, 287 — spleen in, 163, 299 — thymus in congenital, 299 Tetany, 253* Texas fever, hsmolymph glands in, 169 Thyroid enlargement, 122 Toxaemias, 239* Toxic anaemia, 64 Trachoma, 255! Trichinosis, 254t Trypanosomiasis, 239*, 315, 316, 317 Tuberculosis, 109, 139*, 184*, 217*, 219*, 226*, 239*, 253*, 254*, 274t, 316, 317 — bone-marrow in, 50 — pleural exudate in, 152 Tumours, 217*, 218* Typhoid fever, 88, 184*, 217*, 218*, 254t, 273t, 318 bone-marrov/ in, 199 spleen in, 192, 299 Ur-emia, 208*, 253* Urticaria, 253*, 25it ZosTEK, 253-' 385 INDEX OF ANIMALS REFERRED TO IN THIS VOLUME. ACANTHODACTYLUS, I47, liS? Actinia, i86 Agama lymphoidocyte, ii, 147, 187 Algiroides nigropunctatus, 11, 147 Amblystoma, 34, 276 Amphibia, 11, 33, 93, 146, 1S5, 186, 187, 231, 258, 265 Anguilla, 11, 146, 187, 190 Anguis, 147, 25S Anolis, 147, 187 Ape, 144, 232 Arthrostracea, 230 Axolotl, II, 94, 19S Bat, 262 Beetle, 168, 250 Bird, II, 51, 73, 78, 95, 97, 147, 169, 186, 187, 251, 252, 258 Camel, 96 Carassius, 187, 257 Carp, 186 Cat, 77, 83, 168, 232 Caterpillar, 28 Chameleon, 11, 95, 147, 187, 258 Chick, 57, 265 Child, 252, 253 Ciona intestinalis, 230 Cobitis, II, 146 Cod, 187, 190 Cow, 232 Crustacea, 92, 186, 230 Dog, 77, 83, 168, 232, 261 Dogfish, 146 Duck, 147 ECHINODERMS, 86, 92 Emys lutaria, 76, 190, 250, 258 Finch, 187, 232, 265 Fish, 9, 93, 146, 187, 224, 225, 230, 265 Fowl, II, 34, 76, 147, 190. 232, 250, 265 Frog, 76, 139, 147. 187, 190, 231, 232, 252, 258, 276, 277 Gadus lota, 187, 190 Garter snake, 276, 277 Genera], 10, 11, 92 Goat, 232 Gongylus, 231 Goose, 147, 232 . Grass snake, 187, 258 Guinea-pig, n, 78, 83, 89, 143, 344. I77, 232, 254, 261, 264, 300, 301, 303 Hedgehog, 261 Hemidactylus, 250 Hen, 35 Horse, 77, 168, 232, 262, 265 Hyla, 258 Iguana, 258 Infant, 207, 236 Invertebrates, 9, 92, 186 Kangaroo, 303 Kingcrab, 28, 230 Lacerta, II, 187, 190, 250, 258 Leuciscus, 187 Limulus, 28, 230 Lizard, 11, 95, 187, 257, 258 Mammals, 232, 258, 276 Mexican axolotl, 11 Molluscs, 92 Mouse, 77, 78, 83, 232, 303 Mudfish, 231 Nemertines, 224 Newly born, 109 Newt, II, 147, 186, 258 Ophiosaurus acanthodactylus, 11, 187, 25c Ox, 77 Perch, 146, 187 Petromyzon, 76, 93, 146 Pig, 232, 262 Pigeon, 77, 96, 231, 232, 265 Platydactylus, 11 Polyodon, 34, 146, 230, 276, 277 Proteus, 258 Protopterus, 252 Puppy, 161 Rabbit, 78, 83, 102, 199, 225, 232, 252, 261, 264, 270, 303 Rana (see Frog) Rat, 88, 120, 167, 168, 181, 232, 250, 262 Reptiles, 11, 94, 146, 187, 231, 232, 257 Ruminants, 169 Salamander, ii, 13, 97, 147, 190. 258 Scincoid lizard, 11 25 386 Index of Animals Scorpion, 230 Scyllium, 76, 93, 225 Selacia, 33 Senegal finch, 232 Shark, 186 Sheep, 59, 168, 232 Siredon, 11, 147, 231, Skink, 258 Sparrow, 76 Spelerpes, 258 Swan, 147 Swine, 169 250 Teal, 147 Tegenaria, 230 Teleosteans, 186, 230 Tinea, 11, 187 Torpedo, 93, 146, 230 Tortoise, 11, 147, 187, 224, 257, 258 Triton, ir, 76, 97, 147, 186, 231, 258 Tunicate, 230 Vertebrates, 143 White mouse, 232 Worms, 92 387 INDEX OF AUTHORS REFERRED TO IN THIS VOLUME. Abetti, 226, 331 Abrami, 75, 77, 325 Achard and Ramond, 222, 331 — and Weil, 300, 334 Adami, 313, 335 AfEanassiew, 85, 325 Alagno, 275. 334 Albrecht, 168 Alibert, 337 Altmann, 145, 339, 340, 362 Andrewes, 121, 327 Ameth, 78, 197, 214-217, 249, 330, 332 Arnold, 33, 225, 251, 252, 258, 331, 332, 333> 339. 340 Amot, 309 Amsperger, 291, 334 Asai, 161, 328 Ashenheim and Benjamin, 317, 335 — and Tomono, 253 Asher, 118, 141, 167, 329 Ashheim, 303 Askanazy, 55, 58, 78, 79, 80, 299, 301, 324, 334 Aubertin, 350, 354 — and Beaujard, 202, 330 Audry, 264 Auer, 9, 24, 323 Aynaud, 86, 326 Azzurini, 52, 167, 429 Baes and Lustig, 49 Baldoni, 139, 327 Banti, 40, 41, 301, 334 Bartel, 118, 141, 154, 328 Baum and Halle, 115, 130, 327 Baumgarten, 273 Beck, 339 Beckton, 145 Benacchio, 230, 252, 264, 332, 333 Benda, 70, 273, 288, 334, 341, 344, 350, 354 Bennecke, 235 Bergel, 31, 139, 142, 167, 184, 322, 327, 328, 329, 330 Berka, 254, 262, 333 Besredk^, 184 Besangon at Labbe, 299 Bezanfon, 118 Biebergeil, 75 Biedl and Decastello, 121 Biernacki, 91 Bilamioni, 202, 330 Bin, 184 Biondi, 77, 82, 325 Bizzozzero, 86, 326, 340 — and Salvioli, 55 — and Torro, 51, 324 Block, 63, 78 Blumenthal, 30, 40, 49, 67, 74, 93, 144, 167, 180, 208, 212, 323, 325, 329 Bogdanoa, 225, 331 Bbllke, 79, 325 Bonniger, 63 Borka, 327 Borst, 285, 293, 334 Botkin, 283 Bottino, 226, 229, 331, 332 Braunstein, 167, 329 Bremer, 339, 349 Brockbank, 86, 87, 326 Brodie and Russell, 85, 87, 325 Brotz, 267, 333 Brown, 226, 331 Browning, 28, 322 Briicke, 362, 370 Brugsch and Schilling, 213, 214, 216, 330 Brumpt, 88, 326 Bruntz, 186, 230, 330, 332 Bryce, 324 Buch, 360 Buckmaster, 88, 326 Bunge, 73, 325 Bunting, 50, 86, 87, 323, 324, 326, 327 Burian and Schur, 140 Buschke-Hirschfeld, 309, 335 Butterfield, 32, 274 Cabot, 83, 325, 340 Carletti, 270 Carnegie Dickson, 45, 195, 330 Carnoy, 343 Caro, 327 Carpi, 182, 329 CasteUino, 78, 339 Celli, 339 Centanni, 74 Cesare Biondi, 82, 325 Cesaris Demel, 75, 144, 229, 325, 331, 332, 366 Chauffard, 77 — and Fiessinger, 75, 325 Ciaccio, 51, 117, 120, 130, 142, 167, 177, 186, 198, 200, 205, 224, 225, 226, 227, 322, 324, 327—333. 343 351. 362, 365, 368 — and Pizzini, 161, 328 Cicaterri-Bono, 102, 326 Cohnheim, 142, 328, 366 Coie, 174. 329. 355 Coley, 309 Commessatti, 226, 331 Cornil, 353 Cottini, 98, 326 Creszenzi, 140, 167, 328 Cruikshank, 198, 330 388 Index of Authors Da Costa, 226, 331 Dantschakoff, 29, 34, 53, 57, 86, 206, 263, 322, 326, 330, 344, 365, 368 Danzelt, 35 Darier, 354, 361 David, 69, 324 Davis and Carlsson, 148, 328 V. Decastello, 305, 335 Decastello and Krjukoff, 87, 223, 331 Deetjen, 85, 214, 325, 330 Deganello, 273, 283 Dehler, 92, 144 Dekhuyzen, 326, 368 Demel (see Cesaris Demel) Denys, 51, 118, 324 Deutschmann, 256 Dickson, Carnegie, 45, 195, 330 Dietrich, 62, 70, 72, 75, 80, 82, 306, 309, 324, 325. 335 Dinkier, 168, 329 Dixon and Maiden, 38, 323 V. Domarus, 41, 42, 323, 358 Dominici, 33, 55, 273, Z99> 303, 3i4. 330, 339. 353 DonzeUo, loi, 326 Downey, 34, 146, 223, 230, 276, 322, 323, 328, 331, 332, 334 Drozsda, 42, 309, 323 Drzewina, 34, 146, 224, 322, 328, 331 Duesberg, 49, 323 Dumas, 299 Dunger, 236, 332 Dutton, 9, 323 Duval, 292 Ebeehardt, 95, 147, 326 Eberth, 86, 326 Ebner, 50, 303, 324 Ehrlich, 18, 19, 30, 41, 63, 66, 67, 71, 78, 79, 82, 91, 103, 136, 144, 171, 180, 222, 262, 264, 271, 333, 338, 342, 35i> 352, 364. 365 Ehrlich-Lazarus, 103, 301, 334 Ehrlich-Pincus, 334 Eisen, 86, 326, 364, 367 Ellerraann, 35, 41, 323 Eminet, 86, 326 Enderlen and Justi, 272, 273, 274, 333 Engel, 55, 56, 63, 66, 67, 78, 79, 87, 94, 103, 324, 344, 353, 356 Engel and Griineberg, 28, 322 Eppinger, 253 Erben, 227, 331 Erdely, 140, 327 Erdmann, 299 Errera, 210, 2r2, 330 Ewing, 309 Fabian, 42, 306, 323, 335 Fahr, 262 Falte, 239, 253, 332 Faltin, 168, 329 Ferrata, 73, 75, 79, 90, 108, 144, 145, 176, 182, 325, 328, 329, 344, 365 — and Pappenheim, 178, 328, 329 — and VigUoli, 76, 78, 83, 325 Fiessinger, 77, 325 Fischel, 142, 328 Fischer, 71, 306, 335 Fleischmann, 35 Flemming, 114, 117, 303, 327, 353 Foa, 50, 75, 107, 199, 267, 317, 324, 335, 338 Foster, G., 255 — L, 297, 334 Fourgeot, 168, 329 Frank and Isaac, 305, 335 Frankel-Much, 309 Freidsohn, 94, 146, 326, 328 Freytag, 65, 324, 337 Friedstein, 63, 82, 325, 327 Frumkin, 182, 329 Fry, 93, 146, 224, 230, 326, 328, 331, 332 Fuchs, 252 Fuld, 346, 357, 368 Fumo, 232, 332 Gabriel, 83, loi Gabritschewsky, 78 Galambos, 139, 327 Gardella, 227, 331 Gautier, 236, 332 Gerhartz, 142, 328 Ghedini, 197 Ghika, 299 Gibelli, 107, 327 GigUo Tos, 75, 84, 325 Gluzinski, 267 Goldmann, 278, 333 Gollasch, 251 Goodall, 59, 324, 335, 360 — and Guliand, 121 and Paton, 140, 328 Grawitz, 32, 33, 61, 63, 71, 72, 77-80, 103, 104, 112, 133, 140, 144, 145, 146, 177, 178, 180, 220, 309, 324, 325, 327, 347. 351. 353. 360 — and Rosenthal, 148 Griesbach, 71 Grimani, 274 Gross, 138, 167, 329 Grossenbacher, 167, 329 Griineberg, 28, 78, 80, 178, 184, 231, 322, 332 Gruner, 50, 132, 199, 278, 298, 309, 322, 323. 327, 330, 334,335 Griinsky, 184 Guarneri, 339 Guliand, 130, 144, 223, 331, 335 Hamel, 79 Hamer, 150, 328, 360 Hanstein, 340, 358 Hardy, 230, 332 Harris, 264, 272, 333 Hartwich, 82, 325 Harvey, 139, 327 Hayem, 88, 97, 326, 340, 345, 368 Hecker, 299 Hedinger, 112, 308, 327, 335 Heidenhaim, 13, 18, 50, 92, 213, 324, 326, 330, 339, 340, 365, 368 Heinecke, 32, 256, 299, 302 Heinz, 82, 325, 326, 367, 368 Helly, 30, 42, III, 180, 205, 208, 212, 229, 273. 306, 330, 332. 334, 335. 344 349. 350, 352, 358, 360, 361 Index of Authors 389 Hertz, 80, 250, 267, 270, 271, 303, 304, 307, 308, 325, 327, 333> 334, 335 Herzog, 82, 325 Hesse Thaysen, 123, 327 Hirschfeld, 24, 33, 41, 55, 62, 86, 102, 105, 232, 252, 297-299, 302, 303, 305, 306, 309, 323, 326, 327, 332, 334, 335, 339, 358 Hirschfeld Kossmann, 147, 187, 330 Hirt, 236 His, 53, 324, 362 Hofmann, 270, 333 Hofmeister, 150, 32S Horbaczewski, 230 Houston, 329 Howard, 255, 256, 333 Howell, 50, 83 Hoyer, 263 Huxley, i Hynek, 9, 114, 185, 323, 330 Isaac and Mockel, 52, 63, 103, 324 Israel, 141 Israel and Lazarus, 309 — and Pappenheim, 84, 325 Jadassohn, 273 Jagic, 133, 144, 181, 208, 328, 329, 330 Japha and Frankel, 300, 334 Jarotzky, 300, 334 Jawein, 79 Joannovics, 272, 275, 334 Jochmann, 227, 331 — and Bliihdorn, 24, 323 — and Schumm, 42 Jolly, 66, 69, 83, 147, 180, 186, 25i, 324, 328, 344, 345, 356, 361, 365 Jones, 357 Jordan, 69, 70, 324 Jungano, 167, 329 Kallmark, 150, 327 Kammerer, 253, 333 Kanitz, 323 Kanter and Goldmann, 310, 335 Kapinow, 107, 327 Kaplan, 229, 331 Kasarinoff, 10, 76, 96, 147, 187, 232, 250, 258, 265, 323, 326, 328, 330, 332, 333 Kasomoto, 82, 325 Kastanuchi, 50 Kalatsclmikoff, 161, 328 Kelling, 291, 334 Kemp, 85, 325 Ketterer, 130 Keuthe, 116, 138, 139, 236, 327, 332 Kimla, 299 Klein, 32, 125, I34, I45, 250, 252, 274, 299, 322, 328 Kling, 130 Klose, 308, 335 Knoll, 13, 323 Koeppe, 71 KoUiker, 50, 67, 323 Kollmann, 224, 230, 332 Konig, 78 Kormbczi, 154, 328 Kostaneckl, 59, 324 Kramer, 109, 327 Krause, 236, 332 Krehl, 103, 326 Kreibich, 252, 332 Kriser, 239, 332 Krompecher, 260, 263, 273, 283, 293, 334,3^4 Kronberger, 70, 142, 324 Kundrat, 41, 306, 335, 355 Kurloff, 329 Kurpjuweit, 299, 303 Labbe, 118, 328 Langaron, 89 La Roy, 314, 335, 355 Lavdovsky, 361, 363 Lazarus, 79, 351 Leber, 227, 331 Lehndorff, 30, 41, 42, 323 Leighton, 256, 323, 333 Leo, 272 Lepine and Popofi, 236, 332 Levaditi, 141, 144, 260 Levy, 38, 323 Lewin, 310, 335 Lewis, 169, 324, 329 Leydig, 346 Lieberkiihn, 70, 169, 324 Lifschitz, 50, 192, 324, 330 Lindberg, 34, 283, 322 Litten, 91, 168, 291, 329, 334 Liubomadrow, 150 Lobenhoffer, 59, 324 Loeb, 28, 221, 222, 322, 33r Loebe and Michaud, 139, 327 Loele, 62, 121, 163, 227, 251, 263, 324, 327, 328, 332 Loew and Bokorny, 223, 331 Lohner, 69, 71, 324 Longcope, 199, 330 Lortol- Jacob, 184 Lessen, 207, 330 Lowit, 9, 33, 88, 112, 225, 236, 323, 331, 334, 343, 351 Luce, 109, 327 Lucibelli, 199, 330 Liidke, 38, 291, 323, 334 Luksch, 267 Luzet, 88, 326 Mabee, 307, 335 MacCallum, 141 McDonagh, 177 Maciesco-Jalenska, 274, 275, 333 Macintyre and Down, 360 Maclachlan, 118, 327 Magi, 223, 239 Malassez, 344, 365 Mangubi-Kudrjavtzewa, 158, 328 Manuchin, 239, 332 Maragliano, 78, 339 Marchand, 247, 291, 303, 334, 35°, 356, on*? Qfin. QftA. ^fifi Marchiafava, 182 Marcuse, r22, 327 Mareiwitz, 302 '^Di OOH, JJ^t JJ"> 357, 360, 364, 366 390 Index of Authors Marino, 225, 331 Marlin, 5 Marschalko, 268, 273, 283, 293, 356, 364 Martelli, 227, 331 Martinotti, 283 Marwedel, 252, 332 Massart and Bordet, 221, 331 Maurer, 77, 325 Maximow, 29, 32, 33, 52, 53, 55, 57, 59, 66, 80, 87, III, 180, 186, 198, 247, 261, 273, 283, 293, 322, 327, 330, 339> 344, 354> 356, 358, 366 Meirowsky, 263, 333, 366 Meisner, 227, 331 Mestral, 186, 330 Metchnikoff, 162, 171, 183, 186, 221, 231, 329, 353. 354. 357, 366 — and Tarassewitch, 118, 327 Meves, 92, 97, 145, 326, 328 Meyer, Erik, 32, 33, 41, 63, 92, 236, 299, 302, 306, 335, 358 Michaeli, 267, 314, 335 Michaelis, 221, 261, 267, 283, 331, 353 — and Wolff, 260, 333 — and Wolff Eisner, 143, 328 Milkowitsch, 222, 236, 331, 332 Miller, 276, 333 MUligan, 307, 335 Minkowski, 200, 330 Minor and Ringer, 218 Minot, 340 Mirano, 236, 332 Mollier, 58, 158, 324, 328 Mondino, 97, 339 Morawitz, 30, 357, 365 Morris, 83 Morse, 24, 85, 323, 325 Mosler, r68, 329 Mosse, 41, 86, 326 MiiUman, 98, 223, 331 Muir, 85, 325. 330 Miiller, 52, 98, 99, 29r, 326, 334 Miiller and Jochmann, 227, 331 Miiller and Rieder, 346 Mya, 63 NaEGELI, 24, 28, 30, 31, 41, 63, 79, 92, III, 115, 144, 171, 205, 247, 256, 299, 303, 322, 323, 352, 353, 354, 356 Nattan-Larier, 299 Nauwerk and Moritz, 299 Negri, 75 Neisser, 273 Neukerich, 226, 331 Neumann, 29, 33, 41, 46, 67, 97, 98, 214, 216, 299, 3or, 303, 304, 322, 323, 326, 327, 330, 334, 361 Neusser, 253, 363 Nicholas, 326 Nickel, 251, 332 Niegolewski, 147, 232 V. Noorden, 72, 325 Norris, 72, 325 Nothnagel, 42, 337, 360 Oehme, 112, 327 Ogata, 50, 324 Opie, 253, 254, 256, 300, 333 Orsos, 69, 324 Orth, 285, 334, 347 Oser and Pribram, 167 Overton, 72 Oxner, 33, 224 Pachon and Gachet, 167 Palma, 42, 309, 323 Paltauf, 41, 299, 334 Pander, 362, 370 Paneth, 362 Pappenheim, 5, 9, xo, 12, 13, 18, 19, 23, 24, 28, 30, 33, 35, 41, 50. 54, 60, 62, 63, 66, 67, 75-78, 82-84, 89, 92, 94, 97, 98, 100, loi, 103, 104, 109, III, 114, 116, 130, 142, 143, 144, 145. 153, 172. 174, 177, 180, 186, 205, 210, 220, 221, 225, 226, 228, 232, 233, 234, 247, 250, 263, 267, 268, 271, 274, 283, 291, 294, 297, 300, 303, 304, 305, 306, 309, 310, 314, 315, 322-335, 344, 346, 347- 351, 353, 357, 366 — and Ferrata, 328, 329 Paremusoff, 179, 190, 191, 304, 329, 330, 335 Pascheff, 122, 255, 283, 327, 333 Patella, 171, 177, 181, 182, 283, 329, 343, 352-354, 363, 367 Pauliczek, 167, 317, 329 Pavy, 139 Pawlow, 167 Peckelharing, 365 Penny, 150, 184, 328, 330 Perlmeschko, 49, i6r, 323, 328 Petry, 251, 252, 253, 332 Petterson, 351 Pfeiffer and Wassermann, 141 Pincus, 30, 41 Pirone, 115, 162, 201, 252, 255, 275, 327, 328, 330, 332, 333, 334 Plehn, 91, 339 Podwyssozlci, 292, 334 Poggi, 75 Pohl, 139, 328 Pol, 83 Poletaew, 150 Policard and Mawas, 186, 330 PoUitzer, 220, 223, 331 Popielski, 167, 329 Porter, 98, 326 Pratt, 85, 325 Preisisch and Helm, 86, 326 Proell, 272, 333 Proscher, 141, 153, 254, 265, 328, 333 Pugliese, 49, 323 Qdain, 169, 329 Quarelli and Bottino, 226, 229, 33r, 332 Radasch, 324 Radford, 168, 329 Randnitz, 263 Rawitz, 98, 326 Rechzeli, 78 Recklinghausen, 96, 326 Reed, 358 Reichenstein, 267 Index of Authors 391 Reicher, 98, 252, 326, 333 Reid, 85, 325 Renaud, 369 Rheindorf, 265, 274 Ribadeau, 299 Ribbert, 42, 286, 297, 306, 327, 330 Rieder, 350, 366 Rieux, 184, 330 Rindfleisch, 66, 323 Ringer, 218 Riva and Zoja, 75, 325 Roberts, 70, 324 Robertson, 170 Rollett, 71, 324 Romanowsky, 143 Rona and Takhaschi, 73, 325 Roscoe King, 69, 85, 324, 326 Rosenthal, 73, 82, 98, 132, 149, 325, 326, 328 Rosin, 75, 340, 345, 356, 360 Rosin Demel, 366 Ross, 65, 80, 132, 137, 241, 325, 332, 339, 349 Roth, 249, 332 Rous, 139, 252, 254, 327, 333 Roux and Driesch, 74 Rubens, Duval et Fage, 118, 327 Rubinstein, 109, 304, 327, 335 Runeberg, 42 Russo, 220, 331 Saar, 80 Sabin, 130 Sabrazes, 79, 94, 96, 326 — et Lafon, 265, 333 — et Muratet, 93, 96, 146, 225, 230, 231, 232, 326, 328, 332 u, et Durroux, 232, ,332 Sacharofi, 252 Sala, 97, 326 Sanfelice, 50, 323 Sansanow, 255, 333 Sapegno, 61, 69, 85, 176, 227, 324, 329 Sattler, 73. 325 Saxer, 58, 130, 324, 354> 356 Schafer, 53, 69, 71, 85, 86, 220, 324, 326, 331. 349. 352, 357, 359. 364 Schatiloff, 299, 334 Schaumann, 79, 92 Schifone, 184, 232, 330, 332 Schilling, 61, 64, 65, 69, 70, 77. 80, 87, 88, 89, 213, 214, 216, 218, 220, 324, 325. 326, 331 Schimmelbusch, 86, 326 Schleip, 33, 83, 325, 347, 353, 354 Schlesinger, 273, 276, 334 Schlicht, 254 Schmauch, 339 Schmidt, 12, 42, 78, 80, 83, 117, 123, 301, 323, 327, 335 Schmorl, 112 Schneider, 224, 264, 331, 351 Schottlander, 273, 283, 293 Schreiber, 264 Schridde, 19, 3°. 32. 41, 49. 5o. 87, m, 122, 123, 150, 180, 206, 207, 247, 251, 256, 264, 268, 271. 273, 283, 285, 299, 322, 323. 327. 330. 334. 341. 342. 349. 351, 354. 356, 360. 361. 365 Schwalbe, 339 — and SoUey, 82, 325 Schwenter-Trechler, 263 Schiiffner, 77, 325 Schuhmacher, 122 Schultz, 71 Schultze, 35, 89, 339 Schumberg, 148 Schur and Grawitz, 225 Schwarz, 225, 252, 255, 331, 332, 333 — and Micheelis, 301, 334 Scott, 303 Scotti, 167, 329 Scrimger, 297, 334 Selling, 149, 239, 300, 328, 332, 334 Senator, 109, 327 Sergent, 88, 326 Sherrington and Balance, 272 Siegfried, 164, 328 Simon, 255, 299 Sirensky, 141 Sluka, 83, 325 Smith, 285, 333 Spadaro, 179, 329 Spiegelberg, 360 Spilling, 367 Spodara, 85, 325 Staffel, 271 — and Rheindorf, 265 Stephan, 231, 252, 332, 333 Sternberg, 28, 30, 33, 41, 42, 50, 87, 134, 300, 303, 322, 326, 334, 350, 353, 354. 360, 367 Stewart, 72, 324 Stheemann, 118, 327 Stohr, 112, 255 Strausz, 42, 309, 323 V. d. Stricht, 50, 343 Swart, 299 Swingle, 85, 325 Szokalski, 167, 329 Tettenhamer, 253 Thayer, 61, 324 Thoma, 119 Thomson, 5 Timofijwsky, 51 (footnote) Tomaszewski, 291, 334 Tommassi, 49, 50, 323 Torday and Schwartz, 141 Tos, 75, 84, 325 Tousset and Troisier, 227, 331 Trincas, 100, 326 Troje, 352-354 Trousseau, 347 Tschistowitsch, 142, 328 Tsunota, 330 Tiirk, 33, 41, 63, 78, in, 114, i7r. 246, 283, 349. 353. 354. 355, 363 Unna, 261, 262, 268, 271, 272, 333, 364, Uskoff, 299 369 Vaquez, 364 Vassale, 75 Verson, 49, 323 392 Index of Authors Vincent and Harrison, i6o, 329 Virchow, 42, 195, 309, 323 Voswinckd, 35 — and Dimzelt, 291, 334 Waldeyer, 268 Walker, 49, 77, 198, 323, 330 — Ross and Moore, 70, 84, 324, 325 Wallgren, 32, 270, 274, 333 Walz, 303, 351 Wanters, 141 Warthin, 169, 309, 329 Washburn, 91 Wassermann, 118 Weichselbaum, 24, 323 Weidenreich, 33, 38, 67, 69, 71, 75, 78, 87, III, 114, 146, 180, 216, 221, 229, 252, 257, 261, 263, 264, 283, 303, 323, 324, 327, 343. 344. 352, 354, 358, 369 Weil, 299 Weiss, 251, 332 V. Wendt, 123, 327 Wenzlaff, 96, 326 Werigo and Jaguinow, 50, 324 Werner, 295 Wernstedt, 236, 332 Werzberg, g, 10, 35, 76, 88, 92, 97, gS, 145, 147, 187, 190, 250, 257, 300, 301, 304. 323. 326, 328, 330, 333, 334 Widal, 75, 77 — et Abrami. 75, n, loi, 325, 326 Wieland, 360 Wiener, 98, 326 Wiens, 227, 331 Wiens-Schlecht, 251, 332 Wiesner, 340 Winkler, 168, 222, 329, 331 Wlassow, 339 Wolf, 275, 276, 333 Wolff, 180, 29g, 303. 351, 353. 354, 355. 362, 370 Wolff and Arpad, 141 Wolff-Eisner, 338 Woltmann, 170, 254, 329, 333 Wooldridge, 88 Woskressenski, 226, 331 Wright, 50, 85, 87, g8, 323, 324, 325, 326 Yamasaki, 306, 309, 335 Zahn, 360 Zehner, 239, 332 Zenoni, 339 Ziegler, 30, 35, 41, 42, 63, 103, in, 180, 247. 273, 334, 335, 354, 355, 358, 359. 360 Zimmermann, 167, 329, 340, 342 Zoja, 22, 29, 38, 51, 73, 74, 107, 229, 236, 237. 322, 323, 325, 332, 344, 350, 352, 353. 359. 365, 370 Zuntz, 148 3979.13 JOHN WRIGHT AND SONS LTD., PRINTERS AND PUBLISHERS, BRISTOL. CO or CD LU GO or o >- or >~ ■< cc or UJ L^l