title: Anti-idiotypic antibodies to anti-HLA receptors induced by pregnancy.
abstract: We have previously shown that lymphoblasts alloactivated in vitro acquire the capacity of stimulating the autologous mixed lymphocyte response. This response is anti-idiotypic in nature because lymphocytes so primed display accelerated memory responses only when restimulated by autologous lymphoblasts that have been alloactivated against the same HLA-DR antigen. Based on this observation we have postulated that the absence of HLA antibodies in alloimmunized human subjects may be due to the development of autoantibodies that react with the anti-HLA receptors expressed by primed lymphocytes or by anti-HLA antibodies or both. This hypothesis has been confirmed in the present investigations which show that sera from parous women react with autologous T lymphoblasts primed in 5-day mixed lymphocyte culture against their husband-i.e., with lymphoblasts expressing receptors for the immunizing donor. Anti-HLA receptors expressed by T and B lymphocytes seem to share serologic determinants because sera that bind to autologous alloactivated lymphoblasts are also capable of inhibiting the anti-HLA activity of autologous and homologous sera. Auto-anti-idiotypic antibodies inhibit the autologous mixed lymphocyte response to autologous alloactivated lymphoblasts, a phenomenon whose in vivo correlate may reside in autoinhibition of anti-HLA antibody formation and of allograft immunity. Because auto-anti-idiotypic antibodies were found in sera from all parous women tested, the hypothesis that nonresponsiveness to alloantigens exists as a state per se is not likely. The passive transfer of antireceptor (idiotype) immunity by use of antibodies from pregnant women's sera may provide a powerful tool for specific suppression of allograft rejection.
mesh_terms: D000888:Antibodies, Anti-Idiotypic / Q000276:immunology; D005260:Female; D006680:HLA Antigens / Q000276:immunology*; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D006801:Humans; D007130:Immunoglobulin Idiotypes / Q000276:immunology*; D010298:Parity; D011247:Pregnancy; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*
chemical_list: D000888:Antibodies, Anti-Idiotypic; D006680:HLA Antigens; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II; D007130:Immunoglobulin Idiotypes; D011948:Receptors, Antigen, T-Cell