title: In vivo reexpression of H-2 antigens in B16 melanoma cells.
abstract: We have previously shown that B16-A (H-2b) murine melanoma cells, when cultured in vitro for more than ten passages, have an undetectable or reduced expression of H-2Kb and Db antigens, respectively. We have now studied the possibility to restore H-2 expression (measured by quantitative antisera absorption) in B16-A cells either by a limited (30 days) period of in vivo growth or by treatment with immune interferon. In vivo transplants in allogeneic H-2k or H-2d mice and in H-2-compatible but Mls and multiple non-H-2 loci incompatible mice restored the normal expression of Kb and Db antigens. Cells obtained from tumors grown in syngeneic or in minor histocompatibility antigens-allogeneic mice showed only a weak increase in Db antigens. Such induction of H-2 expression appears to be mediated by the host's immune system, since (1) cells obtained from tumors grown in allogeneic BALB/c nude mice expressed much lower levels of H-2 antigens than those from tumors grown in normal BALB/c mice, and (2) it was possible to induce H-2 expression by growing B16 cells in syngeneic C57Bl/6 mice previously allostimulated with unrelated BALB/c tumor. In vitro treatment with immune interferon restored the expression of both Kb and Db antigens. We hypothesize that H-2 reexpression on B16 cells grown in allogeneic hosts could take place via the nonspecific components of the immune response, such as immune interferon.
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm / Q000096:biosynthesis*; D015972:Gene Expression Regulation, Neoplastic; D006183:H-2 Antigens / Q000096:biosynthesis*; D007371:Interferon-gamma / Q000494:pharmacology; D008297:Male; D008546:Melanoma, Experimental / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C / Q000276:immunology; D008809:Mice, Inbred C3H / Q000276:immunology; D008810:Mice, Inbred C57BL / Q000276:immunology; D008819:Mice, Nude / Q000276:immunology; D009368:Neoplasm Transplantation; D014184:Transplantation, Homologous; D014407:Tumor Cells, Cultured / Q000276:immunology* / Q000637:transplantation
chemical_list: D000951:Antigens, Neoplasm; D006183:H-2 Antigens; D007371:Interferon-gamma