CTSB and malaria: In the asexual blood-stages, responsible for all of the clinical manifestations of malaria, rupture of schizonts to allow egress of invasive merozoites can be efficiently blocked by the cysteine protease inhibitor E64 (Salmon et al., 2001; Wickham et al., 2003; Soni et al., 2005; Boyle et al., 2010), implicating at least one cysteine protease.