Influence of human chorionic gonadotropin (hCG) on in vitro growth of Plasmodium falciparum

Abstract Background During pregnancy, women are more susceptible to Plasmodium falciparum infections and frequently have a higher parasitaemia than non-pregnant women. Several mechanisms are responsible for their increased susceptibility, including down-modulation of immune responses that aid in par...

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Bibliographic Details
Published in:Malaria Journal
Main Authors: Taylor Diane, Zhou James, Thévenon Audrey, Pong Clinton K
Format: Article in Journal/Newspaper
Language:English
Published: BMC 2009
Subjects:
Online Access:https://doi.org/10.1186/1475-2875-8-101
https://doaj.org/article/6813e93a973049589e7b756a0358f59e
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Summary:Abstract Background During pregnancy, women are more susceptible to Plasmodium falciparum infections and frequently have a higher parasitaemia than non-pregnant women. Several mechanisms are responsible for their increased susceptibility, including down-modulation of immune responses that aid in parasite clearance and sequestration of infected erythrocytes in the placenta. Early in pregnancy, a third mechanism may contribute to higher parasitaemia, since it has been reported that addition of human chorionic gonadotropin (hCG) to in vitro cultures of the NF54-strain of P. falciparum results in increased parasite growth rates. The goal of this study was to further examine the effect of hCG on P. falciparum growth. Methods The NF54-3D7, FVO and 7G8 strains of P. falciparum were cultured in vitro with various physiological concentrations of hCG purchased from three sources. Infected erythrocytes were also co-cultured with a human cell line that naturally secretes hCG. Results Results from 14 experiments using different combinations of parasite strains and concentrations of hCG from different sources, as well as the co-culture studies, failed to provide convincing evidence that hCG enhances parasite growth in vitro . Conclusion Based on these data, it seems unlikely that hCG has a direct effect on the rate of parasite growth early in pregnancy.