Demonstration of Fc Receptors on the Surface of B Lymphocytes

Human blood lymphocytes were tested by an immunofluorescence technique for surface immunoglobulin and by a rosette test with IgG-sensitised red cells for Fc receptors. From combined tests and experiments involving fractionation of lymphocyte populations it is concluded that Fc receptors are demonstrable on most B lymphocytes by the rosette test, but only if the red cells are optimally sensitised. These observations are advanced as an explanation of the discrepant results of surface marker tests on B cells.