title: Macrophages as a source of tumoricidal activity (tumor-necrotizing factor).
abstract: Macrophage-enriched peritoneal exudate cells from mice infected with Mycobacterium bovis BCG, macrophage-like tumor cells (PU 5-1.8), and peritoneal macrophages propagated in vitro with macrophage growth factor released tumoricidal activity into the culture medium within 2 to 3 h after stimulation with nanogram quantities of bacterial lipopolysaccharide. The cytotoxic activities from each of the macrophage culture supernatants eluted from diethylaminoethyl-Sephacel columns at a sodium chloride concentration of 200 mM exhibited a molecular weight of 50,000 to 60,000 as estimated by gel filtration, were stable at 56 degrees C for 30 min, and were active at a pH range of 6 to 10. A rabbit antiserum directed against serum-derived cytotoxic activity (tumor-necrotizing factor) from BCG-infected and lipopolysaccharide-challenged mice inhibited all of the cytotoxic activities generated in vitro. This suggests that the macrophage-derived cytotoxins are identical with serum-derived cytotoxic factor, which further implies that the macrophage is the cellular source of tumor-necrotizing factor.
mesh_terms: D000818:Animals; D001202:Ascitic Fluid / Q000276:immunology; D002448:Cell Adhesion; D002460:Cell Line; D003602:Cytotoxicity, Immunologic; D005260:Female; D006133:Growth Substances / Q000494:pharmacology; D007111:Immunity, Cellular; D007739:L Cells; D008264:Macrophages / Q000276:immunology*; D051379:Mice; D009163:Mycobacterium bovis / Q000276:immunology; D009374:Neoplasms, Experimental / Q000276:immunology*; D013154:Spleen / Q000276:immunology
chemical_list: D006133:Growth Substances