Monoclonal antibodies against mouse gamma-interferon inhibit tumoricidal macrophage activation by T lymphocytes.
A monoclonal antibody, AN-18.17.24, specific for murine interferon-gamma (IFN-gamma) was produced by immunizing Wistar rats with IFN-gamma secreted by a T-cell lymphoma, L12-R4, upon stimulation with phorbol myristic acetate (PMA). Antiviral activity as well as tumoricidal activation induced by PMA-stimulated L12-R4 cell supernatant or by Con A-stimulated normal spleen cells were neutralized at the same extent by AN-18 monoclonal antibody. Moreover, depletion experiments showed that inhibition of tumoricidal macrophage activation must be ascribed to the direct binding of the IFN-gamma molecule by AN-18 MAb and not to the interference of the monoclonal antibody with the cell surface IFN-gamma receptor. These studies conclusively demonstrate that in supernatants of T lymphocytes stimulated with polyclonal activators IFN-gamma was the only molecule responsible for macrophage activation in tumor cell killing.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D002460:Cell Line; D003208:Concanavalin A / Q000494:pharmacology; D003602:Cytotoxicity, Immunologic; D005260:Female; D007371:Interferon-gamma / Q000276:immunology*; D008223:Lymphoma / Q000276:immunology; D008262:Macrophage Activation; D012515:Mast-Cell Sarcoma / Q000276:immunology; D051379:Mice; D051381:Rats; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D000911:Antibodies, Monoclonal; D003208:Concanavalin A; D007371:Interferon-gamma; D013755:Tetradecanoylphorbol Acetate