Abstract
WEHI 164 sarcoma cells cultured with monocyte-released cytotoxin (CF) for 4 weeks became resistant to CF-induced cytolysis and were concomitantly rendered resistant to monocyte-induced cytolysis. The resistant cell line (R-WEHI 164) has been stable with respect to resistance to monocyte- and CF-induced lysis for more than 7 months. WEHI 164 and R-WEHI 164 cells adsorbed CF and no significant difference in CF adsorption was observed. The results indicate that CF may be an effector molecule in monocyte-mediated cytolysis.