In vitro Growth Inhibition of Plasmodium Falciparum by Sera from DifferentRegions of the Philippines

摘要

Sera from different malaria endemic regions of the Republic of the Philippineswere compared for their ability to inhibit growth of Plasmodium falciparum in vitro. Dialyzed serum was added to synchronous cultures containing schizonts for either the total 48 hr test period or only the last 24 hr period in order to analyze the effects on erythrocytic invasion and intraerythrocytic growth, respectively. Reduction in 3H-hypoxanthine uptake was used to determine the percent inhibition compared to nonimmune serum. One hundred seventy sera from Mindanao and Palawan in South, the centrally located island of Mindoro, and Luzon in the North, were tested against 4 P. falciparum strains from the Philippines and 1 from Africa. Indirect fluorescent antibody titers were not predictive of inhibition. Inhibition of merozoite invasion rather than intraerythrocytic parasite growth is suggested by this study.