Subpopulations of Human T Cells Identified by Receptors for Immunoglobulins and Mitogen Responsiveness

Human T lymphocytes in peripheral blood have been shown to have receptors for IgG (Tgamma) or IgM (Tmu). Cultured Tgamma cells do not express receptors for IgM and purified Tmu cells do not have receptors for IgG, thus they appear to be distinct T cell populations. Although the two subpopulations show similar response patterns to concanavalin A, Tmu and Tgamma cells exhibit different dose-response curves to phytohemagglutinin. The normal response pattern to phytohemagglutinin requires a mixture of T cell subpopulations suggesting that synergistic interactions may occur.