EpCAM-dependent extracellular vesicles from intestinal epithelial cells maintain intestinal tract immune balance

Nat Commun. 2016 Oct 10:7:13045. doi: 10.1038/ncomms13045.

Abstract

How the intestinal tract develops a tolerance to foreign antigens is still largely unknown. Here we report that extracellular vesicles (EVs) with TGF-β1-dependent immunosuppressive activity are produced by intestinal epithelial cells (IECs) under physiological conditions. Transfer of these EVs into inflammatory bowel disease (IBD) mice induced by dextran sulfate sodium salt decreases IBD severity by inducing regulatory T cells and immunosuppressive dendritic cells. In contrast, decreased endogenous EV production promotes IBD development. IECs produce EVs with increased levels of TGF-β1 upon IBD development in an ERK-dependent manner. Furthermore, these EVs tend to localize in the intestinal tract associated with epithelial cell adhesion molecule (EpCAM). Knockdown of EpCAM in vivo increases the severity of murine IBD, and the protective effect of EVs from IECs with decreased EpCAM on murine IBD is blunted. Therefore, our study indicates that EVs from IECs participate in maintaining the intestinal tract immune balance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Proliferation
  • Dendritic Cells / metabolism
  • Dendritic Cells / pathology
  • Epithelial Cell Adhesion Molecule / metabolism*
  • Epithelial Cells / metabolism*
  • Epithelial Cells / ultrastructure
  • Extracellular Signal-Regulated MAP Kinases / metabolism
  • Extracellular Vesicles / metabolism*
  • Extracellular Vesicles / ultrastructure
  • Female
  • Humans
  • Inflammatory Bowel Diseases / metabolism
  • Inflammatory Bowel Diseases / pathology
  • Inflammatory Bowel Diseases / prevention & control
  • Intestines / immunology*
  • Intestines / pathology*
  • Intestines / ultrastructure
  • Mice, Inbred C57BL
  • Phosphorylation
  • Severity of Illness Index
  • Signal Transduction
  • T-Lymphocytes, Regulatory / cytology
  • T-Lymphocytes, Regulatory / metabolism
  • Transforming Growth Factor beta1 / metabolism

Substances

  • Epithelial Cell Adhesion Molecule
  • Transforming Growth Factor beta1
  • Extracellular Signal-Regulated MAP Kinases