Cytoplasmic immunoglobulins in chronic lymphocytic leukemia B cells.
It is generally assumed that chronic lymphocytic leukemia of B cell origin (B-CLL) is characterized by the presence of surface membrane immunoglobulins (SmIg) and by the absence of cytoplasmic immunoglobulins (CyIg). In a variable number of cases SmIg are not detectable because of their low density on the cellular surface. Because a constant presence of CyIg in 20 subjects suffering from B-CLL has been reported recently, we reexamined 15 SmIg-negative and 10 SmIg-positive B-CLL patients by SmIg and CyIg determinations. We used a direct immunofluorescence method on peripheral blood mononuclear cells for the detection of SmIg and, after fixation, for CyIg. CyIg were detectable in 24 out of 25 cases, with a fluorescence intensity ranging from weak to moderate. The existence of frequent negative results for CyIg determination in B-CLL reported in the literature probably depends on the low sensitivity of the method used. We conclude that CyIg determination is useful in phenotyping every B-CLL patient, especially SmIg-negative ones.
D000951:Antigens, Neoplasm / Q000032:analysis; D000954:Antigens, Surface / Q000032:analysis; D001402:B-Lymphocytes / Q000276:immunology*; D002999:Clone Cells; D003593:Cytoplasm / Q000276:immunology; D005455:Fluorescent Antibody Technique; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000032:analysis; D007147:Immunoglobulin Light Chains / Q000032:analysis; D007136:Immunoglobulins / Q000032:analysis*; D007945:Leukemia, Lymphoid / Q000276:immunology*; D011947:Receptors, Antigen, B-Cell / Q000032:analysis
D000951:Antigens, Neoplasm; D000954:Antigens, Surface; D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D007136:Immunoglobulins; D011947:Receptors, Antigen, B-Cell