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Inhibition of Amebic Cysteine Proteases Blocks Amebic Trogocytosis but Not Phagocytosis.

ABSTRACT:

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.

SUBMITTER: Gilmartin AA

PROVIDER: S-EPMC7184912 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Inhibition of Amebic Cysteine Proteases Blocks Amebic Trogocytosis but Not Phagocytosis.

Gilmartin Allissia A AA Ralston Katherine S KS Petri William A WA

The Journal of infectious diseases 20200401 10

<h4>Background</h4>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.<h4>Methods</h4>Amebic cysteine proteases (CPs) were inhibited using an irreversible inhibitor, E-64d.<h4>Results</h4>Interfering with amebic CPs decreased amebic trogocytosis and amebic ...[more]

PMID: 31999350

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