title: Characterization of determinants encoded by four Qa-1 genotypes and their recognition by cloned cytotoxic T lymphocytes.
abstract: The alloantigens encoded by the four defined Qa-1 genotypes were characterized by cloned cytotoxic T lymphocyte (CTL) recognition. CTL clones specific for Qa-1a- and for Qa-1b-encoded antigens were generated. Examination of the reactivity of these clones with target cells from H-2r and H-2f strains provided the strongest evidence to date for the designation of the Qa-1c and Qa-1d genotypes, respectively, for these strains. Qa-1c-encoded antigens were recognized by most, but not all CTL clones that specifically lysed Qa-1b target cells, thus demonstrating that these antigens lack a Qa-1b-associated determinant. Similarly, Qa-1d encoded antigens were recognized by only half of the CTL clones that lysed Qa-1a target cells. In addition, one CTL clone that was cytotoxic for Qa-1b and Qa-1c target cells demonstrated low affinity, cross-reactive recognition of a Qa-1d encoded antigen. The reactivity patterns of the monoclonal CTL defined five Qa-1 determinants. Qa-1a, Qa-1b, and Qa-1d each encode multiple determinants. Two Qa-1d encoded determinants probably reside on different molecular species. Finally, large numbers of CTL clones tested on panels of target cells indicated that the Qa-1a strains expressed indistinguishable Qa-1.1 antigens and the Qa-1b strains expressed indistinguishable Qa-1.2 antigens. Therefore, additional polymorphism among these strains is improbable.
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000235:genetics*; D002999:Clone Cells / Q000276:immunology; D003429:Cross Reactions; D000939:Epitopes / Q000032:analysis* / Q000235:genetics; D005815:Genetic Code; D005838:Genotype; D006183:H-2 Antigens / Q000235:genetics; D015395:Histocompatibility Antigens Class I; D051379:Mice; D008805:Mice, Inbred A; D008806:Mice, Inbred AKR; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D008814:Mice, Inbred NZB; D011110:Polymorphism, Genetic; D014176:Protein Biosynthesis; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
chemical_list: D000954:Antigens, Surface; D000939:Epitopes; D006183:H-2 Antigens; D015395:Histocompatibility Antigens Class I; C032907:Q surface antigens