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Receptor-mediated phagocytosis elicits cross-presentation in nonprofessional antigen-presenting cells.

ABSTRACT: In cross-presentation by dendritic cells (DCs), internalized proteins are retrotranslocated into the cytosol, degraded by the proteasome, and the generated antigenic peptides bind to MHC class I molecules for presentation on the cell surface. Endoplasmic reticulum (ER) contribution to phagosomal membranes is thought to provide antigen access to the ER-associated degradation (ERAD) machinery, allowing cytosolic dislocation. Because the ERAD pathway is present in all cell types and exogenous antigens encounter an ER-containing compartment during phagocytosis, we postulated that forcing phagocytosis in cell types other than DCs would render them competent for cross-presentation. Indeed, FcRgammaIIA expression endowed 293T cells with the capacity for both phagocytosis and ERAD-mediated cross-presentation of an antigen provided as an immune complex. The acquisition of this ability by nonprofessional antigen-presenting cells suggests that a function potentially available in all cell types has been adapted by DCs for presentation of exogenous antigens by MHC class I molecules.

SUBMITTER: Giodini A

PROVIDER: S-EPMC2642664 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature

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Receptor-mediated phagocytosis elicits cross-presentation in nonprofessional antigen-presenting cells.

Giodini Alessandra A Rahner Christoph C Cresswell Peter P

Proceedings of the National Academy of Sciences of the United States of America 20090213 9

In cross-presentation by dendritic cells (DCs), internalized proteins are retrotranslocated into the cytosol, degraded by the proteasome, and the generated antigenic peptides bind to MHC class I molecules for presentation on the cell surface. Endoplasmic reticulum (ER) contribution to phagosomal membranes is thought to provide antigen access to the ER-associated degradation (ERAD) machinery, allowing cytosolic dislocation. Because the ERAD pathway is present in all cell types and exogenous antig ...[more]

PMID: 19218463

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Receptor-mediated phagocytosis elicits cross-presentation in nonprofessional antigen-presenting cells.

Publications

Receptor-mediated phagocytosis elicits cross-presentation in nonprofessional antigen-presenting cells.

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