The cytotoxic effect of mouse macrophages on syngeneic and allogeneic erythrocytes.

A cytotoxic effect of mouse peritoneal macrophages against syngeneic and allogeneic erythrocytes was demonstrated by isotope release and release of hemoglobin. The cytotoxic effect was dependent on the contact between viable, activated macrophages and target cells. Activation was accomplished by prolonged cultivation of macrophages and by the presence of Zn(++) and Con-A. Immunization did not prove necessary. Morphological observations as well as experiments with various salt concentrations indicate that the cytotoxic reaction may involve some kind of osmotic effect upon the target cells.