In vitro cultivation of exoerythrocytic stages of the human malaria parasite Plasmodium malariae.

Exoerythrocytic stage parasites of Plasmodium malariae were obtained in vitro by inoculating primary cultures of hepatocytes from a chimpanzee (Pan troglodytes) and a monkey (Aotus lemurinus griseimembra) with sporozoites. Schizonts were observed in chimpanzee hepatocytes 8, 11, and 13 days after inoculation. Only 1 schizont was seen in Aotus hepatocytes at day 13. The morphology and development rates of P. malariae exoerythrocytic stages obtained in vitro were similar to those previously described in vivo.