title: IgG or IgM monoclonal antibodies reactive with different determinants on the molecular complex bearing Lyt 2 antigen block T cell-mediated cytolysis in the absence of complement.
abstract: Five rat monoclonal antibodies have been derived that express specificities for determinants present on the molecular complex bearing the Lyt 2 antigen. SDS-polyacrylamide gel electrophoresis of 125I-labeled polypeptides precipitated by each of these antibodies reveal 3 components (150,000, 75,000, and 33,000 daltons), and 2 components (44,000 and 33,000 daltons) when analyzed under nonreducing and reducing conditions, respectively. Two of these antibodies are IgG and are specific for the Lyt 2.2 determinant; the other 3 are IgM and react with determinants other than Lyt 2.2, which are nonpolymorphic. Each of the 5 antibodies can block the cytolytic activities of 5-day MLC cells or of cloned cytolytic T cells in the absence of C. Treatment of responding spleen cells with any of these antibodies and C inhibits the generation of cytolytic activity in MLC.
mesh_terms: D000818:Animals; D000937:Antigen-Antibody Reactions; D001667:Binding, Competitive; D002459:Cell Fusion; D002999:Clone Cells / Q000276:immunology; D003165:Complement System Proteins / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D000939:Epitopes; D007074:Immunoglobulin G / Q000276:immunology*; D007075:Immunoglobulin M / Q000276:immunology*; D007519:Isoantigens; D007959:Lymphocyte Culture Test, Mixed; D051379:Mice; D008805:Mice, Inbred A; D008806:Mice, Inbred AKR; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008970:Molecular Weight; D010455:Peptides / Q000302:isolation & purification; D051381:Rats; D011917:Rats, Inbred Lew; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000939:Epitopes; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007519:Isoantigens; D010455:Peptides; D003165:Complement System Proteins