SHORT REPORT - ROSETTE FORMATION IN PLASMODIUM-OVALE INFECTION

Red blood cells infected by mature stages of Plasmodium ovale obtained from a 56-year-old Thai patient formed rosettes readily with uninfect ed erythrocytes. Ex vivo, the ring stage-infected erythrocytes matured well under the in vitro conditions used for P. falciparum culture, an d the infected erythrocytes formed rosettes when the parasites became mature trophozoites. These rosettes were stable and remained intact un til completion of schizogony. Plasmodium ovale rosettes were similar t o those formed by P. falciparum- and P. vivax-infected erythrocytes. R osette formation appears to be a common property of three species of h uman plasmodia.