Abstract
The Fc receptor (FcR) on human lymphocytes is studied by using soluble immune complexes in antigen excess, prepared between ferritin and rabbit anti-ferritin, and a modification of Coombs’ antiglobulin reaction (double-coating indirect rosette formation). 12% of human blood lymphocytes are shown to have Fc receptors. The FcR on lymphocytes is sensitive to pronase treatment, partially sensitive to trypsin digestion, and is inactivated after short glutaraldehyde fixation of lymphocytes. By cell fractionation experiments, FcR-positive lymphocytes were enriched in cell populations enriched with B cells.