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Autophagy proteins stabilize pathogen-containing phagosomes for prolonged MHC II antigen processing.

ABSTRACT: Antigen preservation for presentation is a hallmark of potent antigen-presenting cells. In this paper, we report that in human macrophages and dendritic cells, a subset of phagosomes gets coated with Atg8/LC3, a component of the molecular machinery of macroautophagy, and maintains phagocytosed antigens for prolonged presentation on major histocompatibility complex class II molecules. These Atg8/LC3-positive phagosomes are formed around the antigen with TLR2 agonists and require reactive oxygen species production by NOX2 for their generation. A deficiency in the NOX2-dependent formation of these antigen storage phagosomes could contribute to compromise antifungal immune control in chronic granulomatous disease patients.

SUBMITTER: Romao S

PROVIDER: S-EPMC3857489 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

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Autophagy proteins stabilize pathogen-containing phagosomes for prolonged MHC II antigen processing.

Romao Susana S Gasser Nathalie N Becker Andrea C AC Guhl Bruno B Bajagic Milica M Vanoaica Danusia D Ziegler Urs U Roesler Joachim J Dengjel Jörn J Reichenbach Janine J Münz Christian C

The Journal of cell biology 20131201 5

Antigen preservation for presentation is a hallmark of potent antigen-presenting cells. In this paper, we report that in human macrophages and dendritic cells, a subset of phagosomes gets coated with Atg8/LC3, a component of the molecular machinery of macroautophagy, and maintains phagocytosed antigens for prolonged presentation on major histocompatibility complex class II molecules. These Atg8/LC3-positive phagosomes are formed around the antigen with TLR2 agonists and require reactive oxygen s ...[more]

PMID: 24322427

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Autophagy proteins stabilize pathogen-containing phagosomes for prolonged MHC II antigen processing

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