title: Lack of distinctive surface antigen on cells transformed by murine sarcoma virus.
abstract: Some murine sarcoma virus (MSV)-transformed mouse 3T3 cells contain the MSV genome in the absence of infectious helper murine leukemia virus (MuLV) and MSV production. These cells, designated S+L- (sarcoma positive, leukemia negative), were analyzed for the presence of a possible MSV-determined membrane antigen by the mixed hemadsorption test and in vitro lymphocyte cytotoxicity assay. Two different serological approaches were used: (a) isoantibody-free sera were obtained by immunizing with MSV of syngeneic origin or by allowing primary, autologous MSV sarcomas to regress, or (b) alloantisera obtained by immunizing C57BL mice with S+L- cells were absorbed with the corresponding nontransformed 3T3 cells until all activity against 3T3 had been removed. While MuLV-superinfected S+L- cells and a culture line of an MSV sarcoma known to produce both MSV and MLV were highly reactive, normal 3T3 and S+L- cells were negative. Similarly, lymph node cells from MSV immune mice or rats did not kill S+L- cells, although they were cytotoxic against target cells known to carry MuLV-associated antigens. Thus, the present study gives no positive evidence for the existence of any MSV-induced new surface antigen in the transformed target cell, known to carry the viral genome.
mesh_terms: D000818:Animals; D000941:Antigens; D000951:Antigens, Neoplasm; D000956:Antigens, Viral; D002460:Cell Line / Q000276:immunology; D002471:Cell Transformation, Neoplastic / Q000276:immunology*; D003601:Cytotoxicity Tests, Immunologic; D006382:Hemadsorption; D007111:Immunity, Cellular; D008214:Lymphocytes / Q000276:immunology; D051379:Mice; D008815:Mice, Inbred Strains; D008979:Moloney murine leukemia virus / Q000276:immunology*
chemical_list: D000941:Antigens; D000951:Antigens, Neoplasm; D000956:Antigens, Viral