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Avirulent strains of Toxoplasma gondii infect macrophages by active invasion from the phagosome.

ABSTRACT: Unlike most intracellular pathogens that gain access into host cells through endocytic pathways, Toxoplasma gondii initiates infection at the cell surface by active penetration through a moving junction and subsequent formation of a parasitophorous vacuole. Here, we describe a noncanonical pathway for T. gondii infection of macrophages, in which parasites are initially internalized through phagocytosis, and then actively invade from within a phagosomal compartment to form a parasitophorous vacuole. This phagosome to vacuole invasion (PTVI) pathway may represent an intermediary link between the endocytic and the penetrative routes for host cell entry by intracellular pathogens. The PTVI pathway is preferentially used by avirulent strains of T. gondii and confers an infectious advantage over virulent strains for macrophage tropism.

SUBMITTER: Zhao Y

PROVIDER: S-EPMC4035997 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature

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Avirulent strains of Toxoplasma gondii infect macrophages by active invasion from the phagosome.

Zhao Yanlin Y Marple Andrew H AH Ferguson David J P DJ Bzik David J DJ Yap George S GS

Proceedings of the National Academy of Sciences of the United States of America 20140414 17

Unlike most intracellular pathogens that gain access into host cells through endocytic pathways, Toxoplasma gondii initiates infection at the cell surface by active penetration through a moving junction and subsequent formation of a parasitophorous vacuole. Here, we describe a noncanonical pathway for T. gondii infection of macrophages, in which parasites are initially internalized through phagocytosis, and then actively invade from within a phagosomal compartment to form a parasitophorous vacuo ...[more]

PMID: 24733931

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