Electron microscopic study of phagocytosis in human spleen in falciparum malaria.

The ultrastructure of the spleen of a patient who died of natural infection of Plasmodium falciparum was studied with emphasis on phagocytosis. Parasitized erythrocytes were shown to interact with the heterogenous populations of phagocytic cells. Phagocytosis occurred predominantly in macrophages than endothelial cells and immature forms of parasites were preferentially phagocytosed. Splenic trapping, pitting and destruction of both infected and noninfected erythrocytes were demonstrated. Other forms of interaction between phagocytic cells and parasitized erythrocytes observed include complex interdigitation, association of loose and tight phagosomes, and preferential sites of adherence, the significance of which need further investigation.