GIANT CELLS 



107 



GIEMSA'S STAIN 



by various counler stains as for Acid 

 Fast Bacilli are recommended. The 

 following is a much abbreviated classi- 

 fication of Giant Cells from Cowdry's 

 Histology 1938 Edition : 



1. Megakaryocytes of bone marrow, 

 granules in cytoplasm, best demon- 

 strated by Gienisa's Stain. 



2. Foreign body giant cells formed 

 probably by a fusion of cells of mesen- 

 chymatous' origin, perhaps of non- 

 granular leucocytes, in response to 

 foreign materials of many kinds- 

 tubercular giant cells, foam cells in 

 leprosy, lympsocystic giant cells of fish 

 (Weissenberg), and possibly Reed- 

 Sternberg cells in Hodgkin's disease. 



3. Osteoclasts (polykaryocytes) of 

 bone marrow and Langhans' giant cells 

 of placenta are normal inhabitants of 

 these organs. Myeloplague and Myelo- 

 plax are other terms for osteoclast. 

 Chorioplague is a plate like giant cell 

 of the chorion. See original account 

 for lack of specific properties of so- 

 called Langhans' cells which designa- 

 tion should be abandoned. 



4. Epithelial giant cells are clearly of 

 epithelial origin. Found in epidermis 

 in chicken-pox and other diseases, oc- 

 casionally in the liver and in kidney in 

 many conditions. Often show nuclear 

 irregularity and evidence of nuclear 

 budding. 



5. H ypertrophied cells can be either 

 normal to meet physiological demands, 

 as enormously enlarged smooth muscle 

 cells of pregnant uterus, or due to vari- 

 ous pathological conditions. Mauth- 

 ner's Giant Cell in the fish brain is al- 

 ways of tremendous size in adults. 



Giemsa's corrosive sublimate fixative. Sat. 

 aq. corrosive sublimate 2 parts, absolute 

 alcohol 1 part. 



Giemsa's Stain. 1. For blood or bacteria 

 in smears. Fix air dried smears in 

 methyl alcohol in a covered dish 3-4 

 minutes. Remove and blot dry. Di- 

 lute stock solution of Giemsa in propor- 

 tion of 1 drop to 1 cc. aq. dest. and stain 

 for 15 minutes. Then wash in aq. dest., 

 blot and dry. If a precipitate is formed 

 in the smear by the stain, invert the 

 slide, support both ends, and the stain 

 will adhere like a hanging drop, kept 

 away from the ends by lines ruled in 

 wax or paraffin . The pH of the aq . dest . 

 used to dilute the stain may be altered 

 by adding very dilute acid or alkali. 

 Optimum pH of 6.4 is given by the 

 McJunkin-Haden buffer. This may be 

 used as diluting medium in place of aq. 

 dest. Usually the azurophile are 

 stained more distinctly and the neutro- 

 phile granules less sharply than by 

 Wright's stain. Bacteria and intra- 



cellular protozoa are better colored than 

 by Wright's stain. The May-Giemsa, 

 and Jenner-Giemsa and the panchrome 

 stains of Pappenheim are important 

 modifications. They are listed sepa- 

 rately. Present situation concerning 

 Giemsa's stain is that American 

 products give equally good results with 

 thin films but the German product 

 appears to be better for thick ones 

 (Conn, H. J., Stain Techn., 1940, 15, 

 41-43). 



2. For sections. Much depends upon 

 the choice of fixative. Formalin, gener- 

 ally employed in 10% solution, acts as 

 a sort of mordant for the blue component 

 so that the blue coloration is particularly 

 strong. Fixation in Regaud's gives good 

 results particularly with Rickettsia, 

 Zenker's fluid is recommended by 

 Wolbach. When this is used it is neces- 

 sary to remove the mercuric chloride by 

 treating the sections with Lugol's solu- 

 tion. They are then washed in 95% 

 alcohol and the last traces of iodine are 

 extracted by 0.5% aqueous sodium 

 hyposulphite for 10-15 min. The hypo- 

 sulphite in turn is washed out in run- 

 ning water about 5 min. and rinsing 

 in aq. dest. See Cowdry's colored 

 figures of Rickettsia, J. Exper. Med., 

 1925, 42, 231-252. Bouin's fluid (75 

 cc. saturated aq. picric acid, 25 cc. 

 commercial formalin and 4 cc. glacial 

 acetic acid) is suggested for intracellular 



Erotozoa (East Coast fever parasites) 

 y Cowdry and Danks (Parasitology, 

 1933, 25, 1-63) because after Giemsa 

 staining it gives the chromatin a 

 desirable purple color (see colored 

 plate). Stain sections placed vertically 

 in staining jars in 1.5 cc. Giemsa's 

 solution plus 50 cc. aq. dest., changed 

 during the first hour, overnight. Dif- 

 ferentiate in 95% alcohol, dehydrate 

 quickly in absolute alcohol, clear in 

 xylol and mount in balsam. 



If the sections are not blue enough add 

 1-2 drops 0.5% sodium bicarbonate and 

 1.5 cc. methyl alcohol to the stain; or 

 remove excess of mordanting potassium 

 bichromate from Zenker fixation by 

 rinsing 1 min. in 1% potassium per- 

 manganate followed by 5% oxalic acid 

 4 min. and thorough washing in aq. 

 dest., or do both. If on the contrary 

 they are too blue mordant in 5% potas- 

 sium bichromate 15 min., rinse in aq. 

 dest. until no more yellow is removed 

 and stain; or add a little colophonium 

 to the alcohol used in differentiating 

 and dehydrating of the sections, as 

 advised by Wolbach, or again do both. 

 Usually Giemsa's stain gives satis- 

 factory results without any special pre- 



