title: An epitope on class II antigens that is maintained across species barriers and important in immunologic functions.
abstract: Serological, functional, and chemical analyses of murine class II antigens were performed using a unique monoclonal antibody, 1E4, which was obtained from a rat-mouse hybridoma. 1E4, which is specific for a monomorphic determinant on HLA-DR antigens in humans and a polymorphic determinant on RT1-Da antigens in rats, detected class II antigens on the cells from mice carrying H-2 haplotypes of b, d, p, q, u, v, k, j, r, but not those with f or s haplotypes. Analysis of two-dimensional gel electrophoresis revealed that 1E4 monoclonal antibody recognized at least Ek/b, d, k and Ab, d molecules. 1E4 blocked the T cell proliferative responses to beef insulin and TGAL in B10 and BALB/c mice, as well as proliferative responses to GLT in BALB/c mice and to PPD in C3H/He mice, as had been demonstrated in other species. Furthermore 1E4 inhibited MLR to stimulator cells that expressed Ab, d or Ek/b, k, d molecules. Taken together, these findings indicate that an epitope detected by 1E4 on class II antigens has been well preserved across species barriers. This epitope may play a major role or be closely related to the functional site that is involved in recognition of nominal antigens by T cells.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000939:Epitopes / Q000276:immunology*; D006183:H-2 Antigens / Q000276:immunology; D006684:HLA-DR Antigens / Q000276:immunology; D006649:Histocompatibility Antigens / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D006801:Humans; D051379:Mice; D008809:Mice, Inbred C3H / Q000276:immunology; D008810:Mice, Inbred C57BL / Q000276:immunology; D008815:Mice, Inbred Strains / Q000276:immunology; D051381:Rats / Q000276:immunology; D013045:Species Specificity
chemical_list: D000911:Antibodies, Monoclonal; D000939:Epitopes; D006183:H-2 Antigens; D006684:HLA-DR Antigens; D006649:Histocompatibility Antigens; D000949:Histocompatibility Antigens Class II; C024138:I-E-antigen