title: Antigen-specific human T lymphocyte clones: mechanisms of inhibition of proliferative responses by xenoantiserum to human nonpolymorphic HLA-DR antigens.
abstract: We studied the effects of xenoantiserum to human nonpolymorphic Ia-like antigens upon in vitro antigen-specific T cell proliferative responses in unfractionated PBL populations and at the monoclonal level. Our findings suggest that the xenoantiserum, although it inhibits the antigen-specific response of unfractionated PBL and allospecific T cell clones, does not inhibit the proliferative response to cloned influenza virus immune human T lymphocytes, and therefore may be mediating inhibition by dual mechanisms: direct inhibition of alloantigen recognition and induction of nonspecific suppression. Kinetic differences may explain these phenomena. In cocultivation experiments with a virus-specific clone, the RaIa antiserum appears to induce an OKT3+,8+,4-, radiosensitive regulatory subset of lymphocytes. When adoptively transferred, these induced cells inhibit the TLC response in an antigen-nonspecific and genetically nonrestricted manner. We discuss the various modes and levels of inhibition of antigen-specific proliferation by anti-Ia antisera and their multiple activities.
mesh_terms: D002999:Clone Cells; D000939:Epitopes; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D006801:Humans; D007518:Isoantibodies; D008213:Lymphocyte Activation; D009975:Orthomyxoviridae / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000939:Epitopes; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II; D007518:Isoantibodies