Lack of an obligate role for IFN-gamma in the primary in vitro mixed lymphocyte response.
We have investigated the relative importance of two lymphokines, IL-2 and IFN-gamma, in the primary murine MLR. Three separate lines of evidence indicate that IL-2 and not IFN-gamma is the relevant lymphokine for both proliferation and activation of CTL in these cultures. No obligate role for IFN-gamma was found. First, CTL activation in the presence of high dose cyclosporin A was partially reconstituted with IL-2, although no detectable IFN-gamma was produced in such cultures. In addition, IFN-gamma could not reconstitute cyclosporin-inhibited cultures. Second, inclusion of a high concentration of several distinct anti-IFN-gamma antibodies failed to inhibit MLR cultures. Third, CTL activation by stimulator cells inactivated by UV irradiation was reconstituted by IL-2, but not by IFN-gamma. These data do not support an autocrine role of IFN-gamma in CTL activation and confirm the importance of IL-2 in the primary murine MLR.
D000818:Animals; D003524:Cyclosporins / Q000494:pharmacology; D007371:Interferon-gamma / Q000096:biosynthesis / Q000502:physiology*; D007376:Interleukin-2 / Q000096:biosynthesis / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects; D007959:Lymphocyte Culture Test, Mixed; D051379:Mice; D011994:Recombinant Proteins / Q000494:pharmacology; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects / Q000276:immunology*
D003524:Cyclosporins; D007376:Interleukin-2; D011994:Recombinant Proteins; D007371:Interferon-gamma