Quantitative variations in the expression of H-2 antigens on murine leukemia virus-induced tumor cells can affect the H-2 restriction patterns of tumor-specific cytolytic T lymphocytes.
Comparative quantitative experiments were designed to study the expression of H-2Kd and H-2Dd antigens on three different leukemia cell lines induced by Gross murine leukemia virus (MuLV)in BALB/c (H-2d) mice. The H-2 restriction patterns of syngeneic cytolytic T lymphocytes (CTL) directed against Gross MuLV-induced tumors were correlated with these quantitations of H-2Kd and H-2Dd antigens, Our results obtained by quantitative absorption of monospecific antisera indicated that the three BALB/c tumor cell lines expressed different amounts of H-2Kd and H-2Dd antigens, with H-2Dd antigen showing the greatest variability in expression because it ranged from barely detectable levels to one-eighth the amount of H-2Dd antigen expressed on normal BALB/c spleen cells. The H-2 restriction patterns of Gross MuLV-specific CTL were directly affected by these quantitative modulations in the expression of H-2Kd and H-2Dd antigens, as revealed by three independent approaches: (a) inhibition of CTL activity by monospecific anti-H-2 sera in the absence of complement; (b)competitive inhibition of CTL-mediated cytotoxicity by the addition of excess tumor cells into the reaction mixture; and (c) analysis of CTL specificities using cloned CTL populations. Our results thus indicate that H-2 restriction of tumor-specific CTL activity can be directed at the target cell level by variations in the expression of H-2 antigens.
D000406:AKR murine leukemia virus / Q000276:immunology; D000818:Animals; D000951:Antigens, Neoplasm; D001667:Binding, Competitive; D002471:Cell Transformation, Neoplastic; D003165:Complement System Proteins; D003602:Cytotoxicity, Immunologic; D000939:Epitopes; D006183:H-2 Antigens; D007106:Immune Sera / Q000494:pharmacology; D007942:Leukemia, Experimental / Q000209:etiology / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D013601:T-Lymphocytes / Q000276:immunology*
D000951:Antigens, Neoplasm; D000939:Epitopes; D006183:H-2 Antigens; D007106:Immune Sera; D003165:Complement System Proteins