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Vacuolar and plasma membrane stripping and autophagic elimination of Toxoplasma gondii in primed effector macrophages.

ABSTRACT: Apicomplexan protozoan pathogens avoid destruction and establish a replicative niche within host cells by forming a nonfusogenic parasitophorous vacuole (PV). Here we present evidence for lysosome-mediated degradation of Toxoplasma gondii after invasion of macrophages activated in vivo. Pathogen elimination was dependent on the interferon gamma inducible-p47 GTPase, IGTP, required PI3K activity, and was preceded by PV membrane indentation, vesiculation, disruption, and, surprisingly, stripping of the parasite plasma membrane. Denuded parasites were enveloped in autophagosome-like vacuoles, which ultimately fused with lysosomes. These observations outline a series of mechanisms used by effector cells to redirect the fate of a classically nonfusogenic intracellular pathogen toward a path of immune elimination.

SUBMITTER: Ling YM

PROVIDER: S-EPMC2118399 | biostudies-literature | 2006 Sep

REPOSITORIES: biostudies-literature

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Vacuolar and plasma membrane stripping and autophagic elimination of Toxoplasma gondii in primed effector macrophages.

Ling Yun M YM Shaw Michael H MH Ayala Carol C Coppens Isabelle I Taylor Gregory A GA Ferguson David J P DJ Yap George S GS

The Journal of experimental medicine 20060828 9

Apicomplexan protozoan pathogens avoid destruction and establish a replicative niche within host cells by forming a nonfusogenic parasitophorous vacuole (PV). Here we present evidence for lysosome-mediated degradation of Toxoplasma gondii after invasion of macrophages activated in vivo. Pathogen elimination was dependent on the interferon gamma inducible-p47 GTPase, IGTP, required PI3K activity, and was preceded by PV membrane indentation, vesiculation, disruption, and, surprisingly, stripping o ...[more]

PMID: 16940170

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