title: T cell determinant mapping between K and I-A with I-region properties.
abstract: We investigated genes in the chromosomal segment between K and I-A. Recombination in strains AQR and A.TL previously established the right-hand K region and left-hand I-A subregion boundaries. This report provides evidence that strains AQR and A.TL differ in their intra-I-region crossover points; AQR has k haplotype genes between K and I-A which A.TL lacks. Using three different strain combinations, we produced antibodies specific for a T lymphocyte determinant, Iat.W41, encoded by genes in the Kk to I-Ak interval. Like A.TL, B10.MBR (an intra-I-region recombinant) lacks the Iat.W41-controlling gene. Immunofluorescence analysis and a cytotoxicity assay detected Iat.W41 determinants on mature T lymphocyte subset; thymocytes, bone marrow cells, B cells and macrophages do not express this specificity. Iat.W41-bearing lymphocytes display the Thy-1.2 antigen, but not Ly-1 or Ly-2 determinants. Iat.W41 expression is independent of non-H-2 genes. In addition to a strong mixed leukocyte reaction, genes between K and I-A contribute to a graft-versus-host reaction. The Iat.W41-controlling locus appears distinct from previously identified I-A loci.
mesh_terms: D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte / Q000235:genetics*; D001402:B-Lymphocytes / Q000276:immunology; D002874:Chromosome Mapping; D003601:Cytotoxicity Tests, Immunologic; D006087:Graft vs Host Reaction / Q000276:immunology; D006183:H-2 Antigens / Q000235:genetics*; D000949:Histocompatibility Antigens Class II / Q000235:genetics*; D051379:Mice; D008805:Mice, Inbred A / Q000235:genetics* / Q000276:immunology; D008810:Mice, Inbred C57BL / Q000235:genetics* / Q000276:immunology; D011995:Recombination, Genetic; D013154:Spleen / Q000637:transplantation; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D006183:H-2 Antigens; D000949:Histocompatibility Antigens Class II