Immunolocalization of Falstatin. Immunofluorescence microscopy. Erythrocytes infected with synchronized 3D7 or W2 parasites were collected every 8 h, stained with DAPI and anti-falstatin antibodies and FITC-second antibody, and then evaluated by immunofluorescence microscopy. Falstatin is present in schizonts, merozoites, and rings, but not in trophozoites, the stage at which the cysteine protease activity of P. falciparum is maximal.

Pandey KC, Singh N, Arastu-Kapur S, Bogyo M, Rosenthal PJ. Falstatin, a cysteine protease inhibitor of Plasmodium falciparum, facilitates erythrocyte invasion. PLoS Pathog. 2006 2(11):e117.