A third class I major histocompatibility complex antigen encoded by a gene in the D region of the H-2d haplotype recognized by cytotoxic T lymphocytes.
The D region of the H-2d haplotype contains five class I genes: H-2Dd, D2d, D3d, D4d and H-2Ld. Although previous studies have suggested the presence of D-end encoded class I molecules in addition to H-2Dd and H-2Ld, segregation of genes encoding such molecules has not been demonstrated. In this report we have used cytotoxic T lymphocytes (CTL) to examine the D region of the H-2d haplotype for the presence of additional class I molecules. CTL generated in (C3H x B6.K1)F1 (KkDk, KbDb) mice against the hybrid class I gene product Q10d/Ld expressed on L cells cross-react with H-2Ld but not H-2Dd molecules, as determined by lysis of transfected cells expressing H-2Ld but not H-2Dd. Although H-2Ld-specific monoclonal antibodies (mAb) completely inhibit H-2Ld-specific CTL from killing B10.A(3R) (KbDdLd) target cells, only partial inhibition of anti-Q10 CTL-mediated lysis was observed, suggesting the presence of an additional D-end molecule as a target for these latter CTL. To identify the region containing the gene encoding the Q10 cross-reactive molecule, we show that anti-Q10 CTL lyse target cells from a D-region recombinant strain B10.RQDB, which has H-2Dd, D2d, D3d, D4d, and H-2Db but not the H-2Ld H-2d, and H-2Ld (including D2d, D3d, and D4d), lacks this anti-Q10 CTL target molecule. Together, these data demonstrate that a class I gene mapping between H-2Dd and H-2Ld encodes an antigen recognized by anti-Q10 CTL. A likely candidate for this gene is D2d, D3d, or D4d.
Mann
D W
DW
Department of Microbiology, University of Texas Southwestern Medical Center, Dallas 75235-9048.
Forman
J
J
D000818:Animals; D000954:Antigens, Surface / Q000235:genetics / Q000276:immunology; D005805:Genes, MHC Class I; D006183:H-2 Antigens / Q000235:genetics* / Q000276:immunology; D064532:Histocompatibility Antigen H-2D; D006649:Histocompatibility Antigens / Q000235:genetics / Q000276:immunology; D015395:Histocompatibility Antigens Class I; D051379:Mice; D008815:Mice, Inbred Strains / Q000235:genetics* / Q000276:immunology; D011995:Recombination, Genetic; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
D000954:Antigens, Surface; D006183:H-2 Antigens; D064532:Histocompatibility Antigen H-2D; D006649:Histocompatibility Antigens; D015395:Histocompatibility Antigens Class I; C032907:Q surface antigens