title: Natural killer and T-cell potentiation by monoclonal IgG against natural killer cell FcR(IgG) or the T3 complex.
abstract: Treatment of human natural killer (NK) cells with monoclonal antibodies of the IgG isotype against NK cell-FcR(IgG) increased lysis of most haematopoietic target cell lines with high or intermediate background NK susceptibility. Treatment of normal non-adherent lymphocytes with an IgG anti-T3 monoclonal antibody also increased lysis against the same target cells. Potentiating anti-FcR antibodies rapidly modulated FcR activity and the capacity of the cells to act as antibody-dependent killers, although such antibodies were demonstrable for a long time at the cell surface. Anti-FcR treatment did not influence concanavalin A (Con A)-dependent killing, in contrast to anti-T3 treatment, which suppressed lectin-dependent lysis but did not influence antibody-dependent killing. The data is compatible with a 'pro-receptor' theory for FcR in NK killing, stating that such receptors may function in the same way as the T3 complex interacts with specific T cell receptors.
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology*; D000920:Antibody-Dependent Cell Cytotoxicity; D000954:Antigens, Surface / Q000276:immunology*; D003208:Concanavalin A / Q000494:pharmacology; D003602:Cytotoxicity, Immunologic; D006801:Humans; D007141:Immunoglobulin Fc Fragments / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology*; D007694:Killer Cells, Natural / Q000276:immunology*; D016169:Lymphocyte Function-Associated Antigen-1; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D016169:Lymphocyte Function-Associated Antigen-1; D003208:Concanavalin A