title: Acquisition of syngeneic I-A determinants by T cells proliferating in response to poly (Glu60Ala30Tyr10).
abstract: The T cell proliferative response in mice to the synthetic polymer GAT is under Ir gene control, mapping to the I-A subregion of the H-2 major histocompatibility complex (MHC). Antigen-dependent proliferation in vitro of in vivo GAT-primed lymph node cells can be inhibited by a monoclonal antibody to Ia-17, an I-A public determinant. Using this antibody for direct immunofluorescent analysis, T cells in GAT-stimulated proliferative culture are identified that express syngeneic I-A during culture. This expression is strictly antigen dependent, requires restimulation in vitro, and requires the presence of I-A-positive adherent antigen-presenting cells. T cells bearing I-A can be enriched by a simple affinity procedure, and I-A-positive cells separated on a FACS are shown to retain antigen-specific reactivity. The acquisition of I-A determinants by T cells under these culture conditions is not nonspecific. The Ia determinants borne by T cell blasts appear to be dictated by the I subregion to which the relevant Ir gene maps, and which codes for the Ia molecule involved in presentation of the antigen. Thus, (B6A)F1 (H-2b X H-2a)F1 LNC express I-Ak antigens when proliferating to GAT but not when stimulated by GLPhe, the response to which is under I-E subregion control. The relation of Ir gene function to Ia-restricted antigen presentation and self-Ia recognition is discussed.
mesh_terms: D000818:Animals; D000939:Epitopes; D005802:Genes, MHC Class II; D006183:H-2 Antigens / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000235:genetics; D007518:Isoantibodies; D008198:Lymph Nodes / Q000276:immunology; D008213:Lymphocyte Activation; D051379:Mice; D008805:Mice, Inbred A; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D010455:Peptides / Q000494:pharmacology*; D011108:Polymers; D011817:Rabbits; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000939:Epitopes; D006183:H-2 Antigens; D000949:Histocompatibility Antigens Class II; D007518:Isoantibodies; D010455:Peptides; D011108:Polymers; C020749:GAT