title: Lack of H-2Ld locus products on a BALB/c fibrosarcoma expressing H-2k-like alien antigens.
abstract: The presence of H-2Ld antigens was evaluated in methylcholanthrene-induced BALB/c fibrosarcomas by a variety of approaches. Transplantation experiments showed that BALB/c-H-2dm2 mice, a mutant strain whose cells do not express H-2Ld antigens, after immunization with BALB/c normal tissues developed a resistance to the growth of two tumours (C-3 and GI-17), but not to a third neoplasm, C-1, which is known to have H-2d- as well as H-2k-like alien antigens. In vitro experiments with cytotoxic T lymphocytes generated against Ld antigens confirmed a loss of Ld antigens on C-1 but not on C-3 tumour cells. Serological experiments with an anti-Ld serum again revealed the presence of H-2Ld determinants on C-3 but not on C-1 cells. Biochemical analysis in SDS-PAGE of immunoprecipitates obtained by specific anti-H-2 sera with NP40 lysates of the tumours studied could detect H-2Kd, H-2Dd and H-2Ld antigens in C-3 fibrosarcoma cells whereas Kd and Dd were the only H-2d molecules found in C-1 lysate along with the H-2k-like specificities. The possible genetic mechanisms which may explain this apparent gain and loss modification of the H-2 profile of C-1 are discussed.
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm / Q000032:analysis*; D003602:Cytotoxicity, Immunologic; D005354:Fibrosarcoma / Q000276:immunology; D006183:H-2 Antigens / Q000032:analysis*; D007111:Immunity, Cellular; D007114:Immunization; D051379:Mice; D008807:Mice, Inbred BALB C; D012513:Sarcoma, Experimental / Q000276:immunology
chemical_list: D000951:Antigens, Neoplasm; D006183:H-2 Antigens