Human Chronic Lymphocytic Leukaemia Surface Markers and Activation of Lymphocytes

Abstract
Cell surface markers and responses of lymphocytes to T [thymus-derived] and B [bone marrow-derived] cell mitogens were studied in 10 patients with CLL [chronic lymphocytic leukemia]. T cells were identified as cells rosetting with sheep red blood cells (SRBC), and S-Ig [surface-immunoglobulin] was used as a marker for B lymphocytes. Most cells from all patients had detectable amounts of S-Ig, and the percentage of cells rosetting with SRBC was low in all cases. Of the lymphocytes from these patients, 3-74% (mean 33%) were positive for the acid esterase (ANAE), which was claimed to be a T cell marker. Some patients had cells that were positive for S-Ig and ANAE. Acid esterase esterase staining was therefore not a valid T cell marker in CLL. In cultures containing the T cell mitogen leukoagglutinin (LA) and the T and B cell mitogen pokeweed mitogen (PWM) the reactivity of the lymphocytes was low. The cells responded vigorously to the T and B cell mitogen protein A (PA); the response was serum-dependent, being strong in a culture medium containing fetal calf serum (FCS), but impaired in the presence of human AB serum. Only 1 patient had cells that responded to the B cell mitogen LPS [lipopolysaccharide].