Macrophage activation: priming activity from a T-cell hybridoma is attributable to interferon-gamma.
Antiviral and macrophage-priming activities in the supernatant medium of a subclone of a concanavalin A-stimulated mouse T-cell hybridoma were investigated. The two activities were associated with a molecular weight of approximately 50,000 and could not be separated by various approaches. Both activities were eliminated by a highly specific neutralizing antibody against mouse interferon-gamma, but not by antibody against interferon-alpha and -beta. The ratio of priming to antiviral activity in the hybridoma culture supernate was indistinguishable from the ratio obtained with mouse interferon-gamma prepared by recombinant DNA technology. It was concluded from these data that the priming activity in hybridoma culture supernates was attributable to interferon-gamma and that this mediator is one form of the lymphokine macrophage-activating factor. Interferon-gamma was greater than 800 times more efficient at priming mouse macrophages for tumor cell killing than was a mixture of interferon-alpha and -beta. This finding contributes to growing awareness that type II interferon may have greater immunoregulatory potential than type I interferons.
D000818:Animals; D000906:Antibodies; D002478:Cells, Cultured; D003208:Concanavalin A; D006825:Hybridomas / Q000276:immunology*; D007370:Interferon Type I / Q000276:immunology; D007371:Interferon-gamma / Q000276:immunology*; D008262:Macrophage Activation; D008264:Macrophages / Q000276:immunology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D013601:T-Lymphocytes / Q000276:immunology*
D000906:Antibodies; D007370:Interferon Type I; D003208:Concanavalin A; D007371:Interferon-gamma