Cross-talk between intestinal epithelial cells and immune cells in inflammatory bowel disease

Sci Rep. 2016 Jul 15:6:29783. doi: 10.1038/srep29783.

Abstract

Inflammatory bowel disease (IBD) involves functional impairment of intestinal epithelial cells (IECs), concomitant with the infiltration of the lamina propria by inflammatory cells. We explored the reciprocal paracrine and direct interaction between human IECs and macrophages (MΦ) in a co-culture system that mimics some aspects of IBD. We investigated the expression of intercellular junctional proteins in cultured IECs under inflammatory conditions and in tissues from IBD patients. IECs establish functional gap junctions with IECs and MΦ, respectively. Connexin (Cx26) and Cx43 expression in cultured IECs is augmented under inflammatory conditions; while, Cx43-associated junctional complexes partners, E-cadherin, ZO-1, and β-catenin expression is decreased. The expression of Cx26 and Cx43 in IBD tissues is redistributed to the basal membrane of IEC, which is associated with decrease in junctional complex proteins' expression, collagen type IV expression and infiltration of MΦ. These data support the notion that the combination of paracrine and hetero-cellular communication between IECs and MΦs may regulate epithelial cell function through the establishment of junctional complexes between inflammatory cells and IECs, which ultimately contribute to the dys-regulation of intestinal epithelial barrier.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Caco-2 Cells
  • Cadherins / metabolism
  • Cell Communication*
  • Cell Line, Tumor
  • Coculture Techniques
  • Connexins / genetics
  • Connexins / metabolism
  • Epithelial Cells / metabolism*
  • Gene Expression
  • HEK293 Cells
  • HT29 Cells
  • HeLa Cells
  • Humans
  • Inflammatory Bowel Diseases / genetics
  • Inflammatory Bowel Diseases / metabolism*
  • Inflammatory Bowel Diseases / pathology
  • Intestinal Mucosa / pathology
  • Macrophages / metabolism*
  • Zonula Occludens-1 Protein / metabolism
  • beta Catenin / metabolism

Substances

  • Cadherins
  • Connexins
  • TJP1 protein, human
  • Zonula Occludens-1 Protein
  • beta Catenin