UC Davis

BACKGROUND: Entamoeba histolytica kills human cells by ingesting fragments of live cells until the cell eventually dies, a process termed amebic trogocytosis. In a previous study, we showed that acidified amebic lysosomes are required for both amebic trogocytosis and phagocytosis, as well as cell killing. METHODS: Amebic cysteine proteases (CPs) were inhibited using an irreversible inhibitor, E-64d. RESULTS: Interfering with amebic CPs decreased amebic trogocytosis and amebic cytotoxicity but did not impair phagocytosis. CONCLUSIONS: We show that amebic CPs are required for amebic trogocytosis and cell killing but not phagocytosis. These data suggest that amebic CPs play a distinct role in amebic trogocytosis and cell killing.