In vitro growth of Trypanosoma musculi in cellfree medium conditioned by rodent macrophages and mercaptoethanol

Abstract

Studies of the roles of certain components of an in vitro culture system for Trypanosoma musculi were conducted. Mouse macrophages were shown to be highly effective in supporting trypanosome growth; the magnitude of growth was proportional to the number of macrophages. Addition of 2-mercaptoethanol to cultures significantly enhanced the rate of parasite growth. Rat spleen cells were only slightly less efficient than mouse spleen cells in supporting growth of T. musculi. Addition of mouse serum to cultures containing mouse spleen cells slightly enhanced growth of T. musculi but depressed the support afforded by rat spleen cells. Conditioned medium, prepared by separately culturing mouse spleen or peritoneal exudate cells, was capable of supporting extensive trypanosome growth. Conditioning was dependent upon the number of cells cultured and the time of culture, an excess of either resulting in medium containing inhibitors of trypanosome growth. Considerable importance is assigned to the future characterization of the trypanosome growth-promoting substances elaborated by macrophages.