ERIE VIOLET BW 



91 



ERYTHROCYTES 



Erie Violet BW (CI, 387) of NAC is an acid 

 disazo dye of light fastness 2 to 3. 

 Directions for use in making prepara- 

 tions of animal and plant tissues are 

 described (Emig, p. 40). 



Erie Violet 3R (CI, 394) of NAC is a direct 

 disazo dye of light fastness 3 not as 

 satisfactory for microscopic work as 

 Erie Violet BW (Emig, p. 40). 



Eriochrome Azurol V (CI, 720), a mordant 

 dye of acid fastness 3 to 4. Gives color 

 like that of Niagara Sky Blue. Direc- 

 tions for use (Emig, p. 52). 



Erythroblasts, see Erythrocytes, Develop- 

 mental Series. 



Erythrocyte Counts do not fall in the scope 

 of this book. It is sufficient to state 

 that they are going out of fashion be- 

 cause of the large experimental error 

 involved and since it is so easy to detect 

 variations in shape, size and maturity 

 of erythrocytes in smears and to measure 

 hemoglobin content of blood by hemo- 

 globinometers. See Reticulocytes. 



Erythrocytes. For chemical and physical 

 studies erythrocytes are particularly 

 adapted, because they can be collected 

 in enormous numbers free from other 

 kinds of cells and from intercellular 

 substances. In order to determine 

 marked differences in size and shape 

 and hemoglobin content examination of 

 fresh blood with direct illumination, or 

 in the dark field, is probably the best 

 procedure. An interesting photographic 

 method for the stereoscopic visualiza- 

 tion of the shape of erythrocytes has 

 been described and illustrated by 

 Haden, R. L., J. Lab. & Clin. Med., 

 1936-37, 22, 1262-1263. For more accu- 

 rate techniques see Wintrobe, M. M., 

 Clinical Hematology, Philadelphia : Lea 

 & Febiger, 1942, 792 pp. A new aniso- 

 cytosis index is proposed by van den 

 Berghe, L., and Weinberger, E., Am. J. 

 Med. Sci., 1940, 199, 478-481. The 

 refractile body of Isaacs (R., Anat. Rec, 

 1925, 29, 299-313) can also be well 

 studied in fresh blood. See Flagella. 



Smears, colored by Giemsa or Wright's 

 stain, are satisfactory for Howell-Jolly 

 bodies, Cabot rings, basophilic stippling 

 and polychromatophilia. For resistance 

 to hemolysis in hypotonic sodium chloride 

 solutions, see Daland, G. A., and Worth- 

 ley, K., J. Lab. & Clin. Med., 1934-35, 

 20, 1122-1136. A lysolecithin fragility 

 test is described by Singer, K., Am. J. 

 Med. Sci., 1940, 199, 466-477. For 

 microfragility tests see K^to, K., J. Lab. 

 & Clin. Med., 1940, 26, 703-713 and for 

 basophilic erythrocytes of the newborn 

 see McCord, C. P., and Bradley, W. R., 

 Am. J. Clin. Path., 1939, Tech. Suppl., 

 2, 329-338. A thorough investigation of 

 erythrocytes in fetus and newborn has 



been made by Wintrobe, M. M. and 

 Schumacker, H. B., Jr., Am. J. Anat., 

 1936, 58, 313-328. A simple method for 

 determination of specific gravity of 

 erythrocytes is described by Reznikoff, 

 P., J. Exper. Med., 1923, 38, 441-444. 

 After hemolysis the stroma remains and 

 can be studied microscopically or chemi- 

 cally. Lipid analyses are particularly 

 significant (Erickson, B. N., et al., J. 

 Biol. Chem., 1937-38, 122, 515-528). 



Experiments have been made with 

 radioactive iron as a means of tagging 

 red blood cells (Cruz, W. O., Hahn, 

 R. F., Bale, W. F. and Balfour, W. M., 

 Ani. J. Med. Sci., 1941, 202, 157-162) 

 which open up a new field for study of 

 age changes because the cells are thereby 

 dated. Stratification of contents of 

 erythrocytes by ultracentrifugation 

 (Beams, H. W., and Hines, E. H., Anat. 

 Rec, 1944, 89, 531). Special methods 

 are given under Hemoglobin, Flagella 

 and Reticulocytes. 

 Erythrocytes, Developmental Series. The 

 technique employed apparently makes 

 a great deal of difference in the conclu- 

 sions reached. See Cowdry's His- 

 tology, 1938 p. 99. 



1. Maximow and Bloom employing 

 mainly permanent preparations list: 



Hemocytoblasts: "... large (up to 

 15m) ameboid, non-granular basophil 

 cells of Ij^mphoid nature." Occur ex- 

 tra vascularly. 



Basophil erythroblasts: The youngest 

 erythroblasts, characterized by the 

 intense basophilia of their cytoplasm. 

 Also called megaloblasts, but "this term 

 is misleading because it was first used 

 for the erythroblasts of pernicious 

 anemia which are cells of quite different 

 nature." 



Polychromatic erythroblasts: So-called 

 because after "fixation and staining with 

 the Romano wsky mixture, especially in 

 dry smears, the protoplasm has a mixed 

 color varying from purplish-blue to lilac 

 or gray." This is due to the presence 

 of two substances, a basophile material 

 and hemoglobin. 



Orthochromatic erythroblasts or normo- 

 blasts : These are smaller "and only 

 slightly larger than the mature, non- 

 nucleated erythrocytes." Since the 

 basophile substance diminishes and the 

 hemoglobin increases, the protoplasm 

 becomes acidophilic "and stains a bright 

 pink with the Romanowsky mixture." 

 They continue to divide mitotically for 

 an unknown number of generations until 

 the nucleus disappears. 



2. Sabin and associates relying chiefly 

 on supravital stains list : 



Endothelial cells: Occur in special 

 "erythrogenic capillaries." 



