Chemiluminescence response of peritoneal macrophages to parasitized erythrocytes and lysed erythrocytes from Plasmodium berghei-infected mice

The chemiluminescence response of normal mouse peritoneal macrophages to parasitized erythrocytes isolated from mice 3 weeks after infection with Plasmodium berghei was examined. Only 4 of 12 animals showed positive responses, whereas 8 showed negative responses. Photomicrographs revealed that only in chemiluminescence-positive animals were parasitized erythrocytes attached to or phagocytized by macrophages. When lysed parasitized-erythrocyte cell suspensions were added to the peritoneal macrophages, chemiluminescence could be induced in all cases. The response was enhanced remarkably by the addition of very small amounts of immune serum. Normal macrophages activated in vitro by supernatant from antigen-stimulated spleen cells from immune mice showed much higher parasite-induced chemiluminescence responses than did nonactivated macrophages, especially in the presence of immune serum.