In vitro anti-Plasmodium activity assays of gametocyte-stage P. falciparum.

A P. falciparum NF54 gametocyte culture was initiated at 0.5% asexual parasitaemia and 4% haematocrit, as previously described⁵⁷. Bacteria were physically separated from parasites by a 0.22-μm porous membrane using a Transwell system (Corning). Filtered bacterial suspension was added to the top chamber and the gametocyte culture was added to the bottom chamber. Gametocytaemia was determined three days post incubation. Over 1,000 erythrocytes were examined for gametocytes in Giemsa-stained blood films. The Plasmodium PI4K inhibitor KDU691 (20 μM; ref. ⁵⁸) was used as a positive control.