Immunoelectron microscopy. Late-schizont stage parasites were incubated with anti-falstatin antibodies and gold-conjugated second antibody and then evaluated by electron microscopy. Labels show individual merozoites (M) and erythrocyte cytosol (EC). Falstatin localizes to the periphery of rings and early schizonts, is diffusely expressed in late schizonts and merozoites, and is released upon the rupture of mature schizonts.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.

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.