In vivo activation of macrophages by T cell-derived lymphokines: killing of tumor cells and schistosomula of Schistosoma mansoni.
We investigated the role of T cell-derived lymphokines for macrophage activation in vivo. We show for the first time that macrophages from casein-pretreated mice can be primed in vivo by intraperitoneal injection of immune interferon (IFN-gamma) and can be triggered by lipopolysaccharide (LPS) in vitro to kill schistosomula of S. mansoni. Similar results were obtained for the activation of tumoricidal macrophages. Injection of casein-pretreated mice with concanavalin A (Con A)-induced supernatant of a long-term T cell clone containing IFN-gamma and macrophage cytotoxicity inducing factor 2 (MCIF2), however, induced macrophage activation in vivo without further addition of LPS in vitro. These experiments show that macrophages can be activated by lymphokines in vivo. In addition, the data suggest that a combination of IFN-gamma with MCIF2 might be more effective than IFN-gamma alone. These data may be relevant for the strategy of treating cancer and infectious diseases with lymphokines.
D000818:Animals; D003208:Concanavalin A / Q000494:pharmacology; D003602:Cytotoxicity, Immunologic; D005260:Female; D007111:Immunity, Cellular; D007371:Interferon-gamma / Q000502:physiology; D008222:Lymphokines / Q000502:physiology*; D008262:Macrophage Activation; D008264:Macrophages / Q000276:immunology*; D008297:Male; D051379:Mice; D008811:Mice, Inbred DBA / Q000276:immunology*; D012555:Schistosomiasis mansoni / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
D008222:Lymphokines; D003208:Concanavalin A; D007371:Interferon-gamma