Fc- and complement-receptor rosette-forming cell ratios in human tonsils and peripheral blood.

Lymphocytes were investigated for both Fc- and complement-rosette-forming cell activities. At least three subpopulations differing in the relative activities of the Fc and complement receptors have been disclosed. In human tonsils a subpopulation of B lymphocytes had a higher complement-receptor activity than Fc-receptor activity. In contrast, the peripheral cells from a patient with a lymphoma and another with an undiagnosed lymphocytic disease contained a population of B lymphocytes with higher Fc-receptor than complement- receptor activity. In three patients with chronic lymphocytic leukemia, B lymphocytes contained both Fc- and complement-receptor activities. No differences between complement- and Fc-receptor activities were evident in normal human peripheral blood. Fc-receptor, but not complement-receptor activity was inhibited by 2% gamma-globulin, or 8 X 10(3) M iodoacetate. EDTA at 1.7 X 19(-2) M concentration has no effect upon Fc- or complement-rosette-forming cells. The activity of both receptors was diminished at 4 degrees C.