title: Potentiating effect of murine interferon-gamma-containing lymphokine preparations on the antiviral and antiproliferative effects of murine interferon-alpha/beta: identification of the potentiation factor as murine interferon-gamma itself.
abstract: Mixed preparations of murine interferon-gamma (MuIFN-gamma) and murine interferon-alpha/beta (MuIFN-alpha/beta) have been shown to induce more than additive levels of antiviral protection, when compared to those induced by these interferons given separately. MuIFN-gamma preparations contain many lymphokines and several of these as well as MuIFN-gamma itself may participate in this potentiation. In the present study, natural as well as three recombinant DNA-derived MuIFN-gamma's, in combination with antibody to MuIFN-gamma have been employed to examine the precise role of MuIFN-gamma. The antiviral effect was examined with a single cycle virus yield reduction assay and the antiproliferative effect with a colony formation inhibition assay. Recombinant DNA-derived MuIFN-gamma was as effective as natural MuIFN-gamma at participating in the potentiation of both the antiviral and antiproliferative activities. Antibody to MuIFN-gamma effectively blocked the potentiation of both the antiviral and the antiproliferative activities of natural and recombinant DNA-derived MuIFN-gamma's. Since the recombinant DNA-derived preparations from E. colie can be assumed not to contain mammalian proteins other than MuIFN-gamma, the data conclusively demonstrate that the potentiation factor in MuIFN-gamma preparations is MuIFN-gamma itself.
mesh_terms: D000818:Animals; D002460:Cell Line; D006224:Cricetinae; D003412:Cricetulus; D004274:DNA, Recombinant; D004357:Drug Synergism; D005260:Female; D007370:Interferon Type I / Q000096:biosynthesis / Q000494:pharmacology*; D007371:Interferon-gamma / Q000235:genetics / Q000494:pharmacology*; D007739:L Cells / Q000502:physiology; D008214:Lymphocytes / Q000276:immunology; D008222:Lymphokines / Q000494:pharmacology*; D008545:Melanoma; D051379:Mice; D008810:Mice, Inbred C57BL; D009522:Newcastle disease virus / Q000502:physiology; D010053:Ovary; D014721:Vesicular stomatitis Indiana virus / Q000187:drug effects*
chemical_list: D004274:DNA, Recombinant; D007370:Interferon Type I; D008222:Lymphokines; D007371:Interferon-gamma