Cross-presentation of synthetic long peptides by human dendritic cells: a process dependent on ERAD component p97/VCP but Not sec61 and/or Derlin-1

PLoS One. 2014 Feb 27;9(2):e89897. doi: 10.1371/journal.pone.0089897. eCollection 2014.

Abstract

Antitumor vaccination using synthetic long peptides (SLP) is an additional therapeutic strategy currently under development. It aims to activate tumor-specific CD8(+) CTL by professional APCs such as DCs. DCs can activate T lymphocytes by MHC class I presentation of exogenous antigens - a process referred to as "cross-presentation". Until recently, the intracellular mechanisms involved in cross-presentation of soluble antigens have been unclear. Here, we characterize the cross-presentation pathway of SLP Melan-A16-40 containing the HLA-A2-restricted epitope26-35 (A27L) in human DCs. Using confocal microscopy and specific inhibitors, we show that SLP16-40 is rapidly taken up by DC and follows a classical TAP- and proteasome-dependent cross-presentation pathway. Our data support a role for the ER-associated degradation machinery (ERAD)-related protein p97/VCP in the transport of SLP16-40 from early endosomes to the cytoplasm but formally exclude both sec61 and Derlin-1 as possible retro-translocation channels for cross-presentation. In addition, we show that generation of the Melan-A26-35 peptide from the SLP16-40 was absolutely not influenced by the proteasome subunit composition in DC. Altogether, our findings propose a model for cross-presentation of SLP which tends to enlarge the repertoire of potential candidates for retro-translocation of exogenous antigens to the cytosol.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP-Binding Cassette Transporters / metabolism
  • Adenosine Triphosphatases / metabolism
  • Antigen Presentation / immunology*
  • Antigens / chemistry
  • Antigens / immunology*
  • Antigens, Neoplasm / chemistry
  • Antigens, Neoplasm / immunology
  • Cell Cycle Proteins / metabolism
  • Cross-Priming / immunology*
  • Dendritic Cells / immunology*
  • Dendritic Cells / metabolism
  • Endocytosis / immunology
  • Endoplasmic Reticulum-Associated Degradation
  • Endosomes / metabolism
  • Humans
  • Kinetics
  • Lysosomes / metabolism
  • MART-1 Antigen / chemistry
  • MART-1 Antigen / immunology
  • Membrane Proteins / metabolism
  • Models, Biological
  • Peptides / chemical synthesis
  • Peptides / chemistry
  • Peptides / immunology*
  • Proteasome Endopeptidase Complex / metabolism
  • Protein Transport
  • SEC Translocation Channels
  • Valosin Containing Protein

Substances

  • ATP-Binding Cassette Transporters
  • Antigens
  • Antigens, Neoplasm
  • Cell Cycle Proteins
  • DERL1 protein, human
  • MART-1 Antigen
  • Membrane Proteins
  • Peptides
  • SEC Translocation Channels
  • transporter associated with antigen processing (TAP)
  • Proteasome Endopeptidase Complex
  • Adenosine Triphosphatases
  • VCP protein, human
  • Valosin Containing Protein

Grants and funding

This work was supported by grants from the Ligue Nationale contre le Cancer and Comite 44, Institut National de la Santé et de la Recherche Médical, Institut National du Cancer (PL074), and the European Network for the Identification and Validation of Antigens and Biomarkers in Cancer and their Application in Clinical Tumor Immunology Network (503306). JM was supported by a doctoral fellowship from the Ministère de l’Ensiegnement Supérieur et de la Recherche. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.