Cultivation of exoerythrocytic stages of Plasmodium cynomolgi, P. knowlesi, P. coatneyi, and P. inui in Macaca mulatta hepatocytes.

Exoerythrocytic stage parasites of Plasmodium cynomolgi, P. knowlesi, P. coatneyi, and P. inui were cultured by inoculating primary cultures of hepatocytes from Macaca mulatta with sporozoites. Less than 1% of inoculated sporozoites survived. Morphology and size of the liver stages in all 4 species were similar to in vivo descriptions and the time required for in vitro maturation correlated well with prepatent periods described.