title: Genetic control of the induction of cytolytic T lymphocyte responses to AKR/Gross viral leukemias. II. Negative control by the Fv-1 locus in AKR mice of responder H-2b haplotype.
abstract: To assess whether the presence of a responder H-2b haplotype would be sufficient to allow mice of nonresponder "high leukemic" phenotype to generate syngeneic anti-AKR/Gross virus cytolytic T lymphocytes (CTL), the AKR.H-2b strain was examined. Although capable of mounting vigorous apparent anti-minor histocompatibility-specific CTL responses, AKR.H-2b mice failed to produce anti-viral CTL after a variety of stimulation protocols. In contrast, the "doubly congenic" AKR.H-2b:Fv-1b strain was able to respond with substantial levels of H-2-restricted anti-AKR/Gross virus CTL activity. These results indicated that Fv-1n alleles could exert negative epistatic control over responder H-2b-encoded gene(s). Because the B6.Fv-1n congenic was also able to generate anti-viral CTL indistinguishable from the prototype B6 strain, however, it was apparent that other genes of AKR background were required for the Fv-1n-mediated inhibition in AKR.H-2b mice. The mechanism by which Fv-1 intereacted with other genes to override positive H-2b control appeared to be related to the expression of the CTL-defined, virus-associated antigens by normal AKR.H-2b cells. Thus, AKR.H-2b spleen cells but not thymus cells were able to stimulate the production of B6 anti-AKR/Gross virus CTL and were recognized as target cells by such anti-viral CTL. In contrast, both spleen cells and thymocytes from AKR.H-2b:Fv-1b mice were negative when tested as stimulator or target cells in these assays. In addition, AKR.H-2b but not AKR.H-2b:Fv-1b spleen cells were shown to display serologically defined gp70 determinants and the Gross cell surface antigen. Taking these data together, it appeared that the inhibition of anti-viral CTL responsiveness might be due to tolerance induced by the cell surface expression of virus-associated antigens by normal AKR.H-2b cells. Widespread display of viral antigens, in turn, may have been due to the permissive effects of Fv-1n on the spread of the early arising N-ecotropic, endogenous AKR leukemia virus controlled by other background genes. In this context, the implications of the multi-gene control of anti-AKR/Gross virus CTL production are discussed with respect to the induction of spontaneous leukemia in the high incidence AKR strain.
mesh_terms: D000406:AKR murine leukemia virus / Q000235:genetics / Q000276:immunology; D000818:Animals; D000956:Antigens, Viral / Q000032:analysis; D003602:Cytotoxicity, Immunologic; D005802:Genes, MHC Class II; D005838:Genotype; D006183:H-2 Antigens / Q000235:genetics* / Q000276:immunology; D006238:Haploidy; D064532:Histocompatibility Antigen H-2D; D007108:Immune Tolerance; D007942:Leukemia, Experimental / Q000235:genetics* / Q000276:immunology; D051379:Mice; D008806:Mice, Inbred AKR; D008810:Mice, Inbred C57BL; D013045:Species Specificity; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
chemical_list: D000956:Antigens, Viral; D006183:H-2 Antigens; D064532:Histocompatibility Antigen H-2D