Cytochemistry of the Lymphocytes 31 



teristic type of slow ameboid movement in which the nucleus advances ahead 

 of the cytoplasm, the so-called hand-mirror movement. 



Estimating the maturity of the lymphocyte from cell size alone is not 

 sufficient and may lead to erroneous interpretation of the lymphocytes' age. 

 Experience has indicated that the most reliable criteria for determining the 

 relative age of the lymphocyte are obtained by the correlation of several 

 morphologic features, e.g., degree of cytoplasmic basophilia, number of 

 mitochondria, cell size, and the chromatin pattern of the nucleus. 5, 112 



Leukemic Lymphocytes 



Lymphocytic Leukemia. Lymphocytes in chronic lymphocytic leukemia 

 (Figs. 3-10, 3-11) are small (9-12 /x) and possess a more dense chromatin 

 pattern than is usually seen in normal small lymphocytes. The hyperchro- 

 matic appearance of the nucleus is dependent, in part, upon the increase in 

 the number of small irregular nucleoli and the "nucleolar associated chro- 

 matin." The contour of the nucleus may vary from a smooth to an irregular 

 rounded form. The cytoplasm of the small lymphoid cells in chronic lympho- 

 cytic leukemia tends to be scantier than in the normal lymphocytes. The 

 number of mitochondria and cytoplasmic granules as well as the degree of 

 basophilia of the cytoplasm may frequently be slightly greater in the leu- 

 kemic than in the normal small mature lymphocyte. 



A complete maturation series of lymphoid cells can occasionally be seen in 

 the blood of certain patients with lymphocytic leukemia (subacute variety) . 

 These immature lymphoid cells tend to exhibit more dense nuclei and have 

 a somewhat greater number of mitochondria and nucleoli than the small 

 lymphocytes of lymphocytic leukemia and comparable normal lymphoid 

 cells at similar stages of maturation. In these cases larger lymphoid cells 

 exhibiting morphologic features of blast cells (Fig. 3-11) are present in 

 relatively small numbers in contrast with the small lymphocytes which pre- 

 dominate. The morphologic features of the lymphoblasts seen in lympho- 

 cytic leukemia differ from cells identified as lymphoblasts in normal 

 lymphatic tissue. 



Fig. 3-7. Normal human lymph node. Note the large lymphocyte with 2 nucleoli, 

 basophilic cytoplasm, and spherical mitochondria localized in the nuclear hof and distal 

 portion of the cytoplasm. Several small lymphocytes are present as well as a stellate 

 reticulum cell (arrow). Supravital preparation of lymph node scrapping. 



Fig. 3-8. Normal human lymph node. Lymphoblast with prominent nucleoli. Mitochon- 

 dria present in the nuclear hof and swollen mitochondria in the distal portion of the 

 cytoplasm. Supravital preparation of lymph node scrapping. 



Fig. 3-9. Normal human lymph node. Lymphoblast containing few mitochondria and 

 cytoplasmic granules. Cytoplasm appears opaque and deeply basophilic. Supravital prep- 

 aration of lymph node scrapping. 



