PLASMODIUM FALCIPARUM-ISOLATES FROM CAMEROONIAN PREGNANT-WOMEN DO NOTROSETTE

The placenta of pregnant women is frequently parasitized by erythrocyt es infected by mature stages of Plasmodium falciparum (IE), a phenomen on associated with low birth weight of the offspring. The cytoadherenc e phenotype of the parasites from pregnant women suggests that placent al sequestration may result from cytoadherence to the syncytiotrophobl ast. However, as anatomopathological studies report that cytoadherence in the placenta is a rare event, we investigated whether placental pa rasites may sequester by forming rosettes with uninfected erythrocytes , another possible sequestration mechanism. Parasites from placental b lood as well as parasites from the peripheral blood of pregnant and no n pregnant subjects were assessed for their ability to rosette. In non pregnant subjects, the rosetting capacity of parasites was as reporte d in litterature while, except in one case, parasites from pregnant wo men did not rosette. We conclude that the lack of rosetting is a new f eature of Ifs from pregnant women and that rosetting cannot be involve d in the plocental sequestration of IEs.