CON-A-INDUCED SUPPRESSOR ACTIVITY OF LYMPHOCYTES DISTINGUISHED BY THE PRESENCE OR ABSENCE OF THE FC RECEPTOR

Lymphocytes bearing a receptor for the Fc region of the IgG molecule (Fcγ+) were separated from those lacking the receptor (Fcγ-) by a two-step procedure involving adherence to antibody-coated bovine erythrocyte monolayers followed by rosetting with antibody-coated bovine erythrocytes and separation on a Ficoll-Metrizoate gradient. Using this procedure, we confirmed previous work showing that cytotoxicity induced by the graft versus host reaction was mediated by cells bearing the Fc receptor. Separated cell populations were cultured with Con-A for 48 hr and then tested for their ability to mediate nonspecific suppression of both primary and secondary responses to SRBC in vitro. Suppressor cells were generated from both Fcγ+ and Fcγ- cells following culture with Con-A. Therefore, no distinct functional differences in the ability to mediate nonspecific suppression can be attributed to subclasses of T-cells on the basis of possession of the FcR. © 1979.