title: Expression of the I-E target antigen for T-cell killing requires two genes.
abstract: The H-2Ik region encodes at least two different target antigens for unrestricted T-cell mediated killing. The first is controlled by the I-A region alone and the second depends on a pair of alleles, one located to the left of I-B (presumably in I-A) and the other to the right of I-J (presumably in I-E). Hence, effector cells nominally specific for a product of the I-E region do not kill target cells with the same I-E region as the stimulator unless the I-A region is also shared. Some effectors specific for H-2Ik, such as A.TH anti-A.TL and B10.A(4R) anti-B10.A(2R), cross-react with B10.A(3R) and B10.A(5R) target cells. A product of the H-2b haplotype was shown to complement products of the H-2d or H-2k haplotypes in forming this cross-reactive determinant. The results are consistent with recent biochemical data on the component chains of Ia antigens.
mesh_terms: D000818:Animals; D003429:Cross Reactions; D003602:Cytotoxicity, Immunologic; D005260:Female; D006183:H-2 Antigens / Q000235:genetics; D006239:Haplotypes; D000949:Histocompatibility Antigens Class II / Q000235:genetics*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
chemical_list: D006183:H-2 Antigens; D000949:Histocompatibility Antigens Class II; C024138:I-E-antigen