Cytochemistry of the Lymphocytes 39 



was employed. Formalin vapor and Formalin fixatives yield better cellular 

 fixation and staining but tend to bind the glycogen to cellular proteins, 

 making the glycogen resistant to both saliva and purified amylase diges- 

 tion. 9 



In contrast to the normal lymphocytes, the glycogen content of the 

 lymphoid cells of chronic lymphocytic leukemia (Fig. 3-28) and lympho- 

 sarcoma (Fig. 3-29) possess relatively large amounts of glycogen. 1 ' 8 - 70 ' 74> 

 !,! * 114 The glycogen content of nucleolated lymphocytes in chronic lympho- 

 cytic leukemia is greater than in nonnucleolated lymphocytes, 11 although 

 other investigators 70 have found no differences. The lymphoid cells of acute 

 lymphoblastic leukemia (Fig. 3-30) differ from those of chronic lymphocytic 

 leukemia and lymphosarcoma in that the lymphoblasts possess little or no 

 demonstrable glycogen with the PAS reaction. 8 ' 70 This finding has been 

 correlated with the absence of phosphorylase activity in the lymphoblasts in 

 acute lymphoblastic leukemia 70 while the phosphorylase activity of the cells 

 of lymphosarcoma and chronic lymphocytic leukemia is present, frequently 

 in relatively large amounts. It has been observed that while in most instances 

 the glycogen content of the cells of lymphosarcoma is increased, the cells 

 from certain patients with this disease may exhibit very little glycogen in 

 their cytoplasm. 8 ' 70 It has been stated 11 ' 7 " that in leukemia glycogen tends 

 to appear relatively early in the maturation of the lymphocyte and increases 

 during cellular differentiation. 



The presence of glycogen in leukemic cells is a significant finding and can 

 be used with discretion as an aid in diagnosis of normal and various lympho- 

 cytic diseases, although it must be remembered that glycogen may also be 

 present in increased amounts in certain nonleukemic conditions exhibiting 

 lymphocytoses, e.g., infectious mononucleosis. 1 - 52, 70 - " Also, glycogen is de- 

 creased in lymphoblastic leukemia 8 ' 70 and in certain cases of lymphosar- 

 coma. s 7 " 



Lipids 



Although most investigators 17 - 46 - 50 - 62 - 74 > 83 ' 86 - 92 - 93 - 100 ' 113 have failed to 

 demonstrate lipids in either normal or abnormal lymphocytes following- 

 staining with fat soluble dyes, e.g., Sudan black, Sudan orange, and oil red O, 

 sudanophilic granules can be seen in the cytoplasm of both mature and 

 developing lymphocytes and lymphoblasts in human lymph nodes. 1 • - These 

 sudanophilic granules are small and inconspicuous and tend to localize near 

 the nuclear hof. They appear to be slightly more numerous and prominent 

 in the lymphoblast than in the mature lymphocyte and probably represent 

 mitochondria and/or cytoplasmic granules or vacuoles. 1 There is no ap- 

 parent difference in the number of sudanophilic granules present in the 



