title: Killing of untreated target cells by nonimmunized rat macrophages in vitro. I. Studies on the type of effector cells and their capacity to destroy allogeneic target cells.
abstract: Spleen cells derived from unsensitized Wistar rats lysed untreated, allogeneic liver cells of high passages (93rd until 159th subculture) as well as allogeneic tumor cells in mixed cultures. On the other hand, rat liver cells between passages 42 and 56 and allogeneic or xenogeneic fibroblasts were not destroyed by rat spleen cells in vitro. The degree of target cell lysis was dependent on the incubation time and effector-target cell ratio. In the rat spleen, the macrophages were detected as effector cells. Rat peritoneal cells showed the same effects as rat spleen cells. Trypsin treatment caused no loss of cytotoxicity of rat macrophages. Thymocytes and blood lymphocytes of rats were not cytotoxic against allogeneic or xenogeneic target cells. The macrophages apparently destroyed target cells by a nonphagocytic form of cell contact. Unstimulated spleen cells of guinea pigs, Syrian hamsters, CBA mice and rabbits were not capable to destroy target cells in allogeneic and xenogeneic systems.
mesh_terms: D000818:Animals; D002460:Cell Line; D006224:Cricetinae; D003602:Cytotoxicity, Immunologic; D006168:Guinea Pigs; D008264:Macrophages / Q000276:immunology*; D051379:Mice; D009374:Neoplasms, Experimental / Q000276:immunology; D011817:Rabbits; D051381:Rats; D013045:Species Specificity; D013154:Spleen / Q000276:immunology