Lymphocyte subpopulations in man: relationship between four subpopulations identified by membrane markers

The interrelationship between four subpopulations of human lymphocytes was studied in eight normal persons. Double marking and fractionation experiments established that lymphocytes with receptors for AET-treated sheep erythrocytes constitute a population complementary to cells that carry surface membrane immunoglobulins as they are identified by polyvalent rabbit anti-human immunoglobulin; the latter includes nearly all cells with complement receptors. Two functionally different receptors for antigen-bound IgG are identified by their binding avidity for rabbit-antibody-sensitized ox erythrocytes, defining populations of lymphocytes with high-avidity and low-avidity receptors, indicating two valuable differentiation markers.