Plasmodium falciparum sexual differentiation in malaria patients is associated with host factors and GDV1-dependent genes

2019

English

Plasmodium sexual differentiation is required for malaria transmission, yet much remains unknown about its regulation. Here, we quantify early gametocyte-committed ring (gc-ring) stage, P. falciparum parasites in 260 uncomplicated malaria patient blood samples 10 days before maturation to transmissible stage V gametocytes using a gametocyte conversion assay (GCA). Seventy six percent of the samples have gc-rings, but the ratio of gametocyte to asexual-committed rings (GCR) varies widely (0–78%). GCR correlates positively with parasitemia and is negatively influenced by fever, not hematocrit, age or leukocyte counts. Higher expression levels of GDV1-dependent genes, ap2-g, msrp1 and gexp5, as well as a gdv1 allele encoding H217 are associated with high GCR, while high plasma lysophosphatidylcholine levels are associated with low GCR in the second study year. The results provide a view of sexual differentiation in the field and suggest key regulatory roles for clinical factors and gdv1 in gametocytogenesis in vivo.

Usui, M.; Prajapati, S. K.; Ayanful-Torgby, R.; Acquah, F. K.; Cudjoe, E.; Kakaney, J. A.; Amponsah, J. A.; Obboh, E. K.; Reddy, D. K.; Barbeau, M. C.; Simons, L. M.; Czesny, B.; Raiciulescu, S.; Olsen, C.; Abuaku, B. K.; Amoah, L. E.; Williamson, K. C.