Mouse natural killer (NK) cell activity against human cell lines is not influenced by superinfection of the target cell with xenotropic murine C-type virus.
Mouse natural killer (NK) cells can lyse a variety of syngeneic, allogeneic and xenogeneic target cells in short-term 51Cr release assays. The target specificity of NK cells is not known, but endogenous C-type viral antigens have been suggested as possible target structures. To test this hypothesis, human lymphoid lines were superinfected with xenotropic mouse C-type virus either by repeated dosage through nude mice or by in vitro superinfection with the supernatants of nude-mouse-passaged lines. The appearance of surface-associated MuLV antigens after superinfection was confirmed in a complement-dependent cytotoxicity test. Subsequently, the NK sensitivity of each infected line was compared with its non-infected counterpart in direct cytolytic and competition assays. None of these two assay systems showed a consistent difference in NK sensitivity of infected and non-infected cell lines. These findings do not lend support to the concept tht murine C-type viral antigens are responsible for NK sensitivity.
D000818:Animals; D000956:Antigens, Viral; D002460:Cell Line; D003165:Complement System Proteins; D003601:Cytotoxicity Tests, Immunologic; D006801:Humans; D007106:Immune Sera; D007694:Killer Cells, Natural / Q000276:immunology*; D008223:Lymphoma / Q000276:immunology; D051379:Mice; D008819:Mice, Nude; D012190:Retroviridae / Q000276:immunology; D014412:Tumor Virus Infections / Q000276:immunology*
D000956:Antigens, Viral; D007106:Immune Sera; D003165:Complement System Proteins