Veto cell H-2 antigens: veto cell activity is restricted by determinants encoded by K, D, and I MHC regions.
Responder cells from primary syngeneic and allogeneic one-way mixed-lymphocyte cultures (MLC) specifically inhibit the development of cytotoxic T lymphocytes (CTL) directed against the major histocompatibility complex (MHC) antigens of the MLC responder cells. This special kind of suppressor activity is known as veto suppression. Ia+ cells with veto activity obtained from H-2 recombinant mouse strains were shown to downregulate alloantigen (class II)-specific helper activity for class I-specific CTL development in a primary MLC provided that the veto cells expressed the same I-E alpha subregion as the MLC stimulator cells. The veto-induced suppression of allo-help was prevented by the addition of supernatant from concanavalin A-stimulated spleen cells (Con A-SN) and was inhibited considerably by very high amounts of recombinant interleukin-2 (IL-2). In the presence of Con A-SN, CTL precursors recognizing either the K end or the D end of the veto cell MHC were found to be inactivated. Thus, our results indicate that MLC responder cells include active veto cells expressing Ia region-encoded restriction elements for allospecific T helper cells, as well as K- or D-encoded restriction elements for allospecific T cytotoxic cells.
D000818:Animals; D002460:Cell Line; D003602:Cytotoxicity, Immunologic; D000939:Epitopes / Q000235:genetics*; D006183:H-2 Antigens / Q000235:genetics*; D006801:Humans; D007376:Interleukin-2 / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology*; D008285:Major Histocompatibility Complex; D051379:Mice; D008815:Mice, Inbred Strains; D051381:Rats; D011919:Rats, Inbred Strains; D011994:Recombinant Proteins / Q000276:immunology; D013045:Species Specificity; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014709:Vero Cells / Q000276:immunology*
D000939:Epitopes; D006183:H-2 Antigens; D007376:Interleukin-2; D011994:Recombinant Proteins