Epidermal growth factor receptor signalling contributes to house dust mite-induced epithelial barrier dysfunction

Eur Respir J. 2010 Nov;36(5):1016-26. doi: 10.1183/09031936.00125809. Epub 2010 Mar 29.

Abstract

Impaired airway epithelial barrier function has emerged as a key factor in the pathogenesis of allergic asthma. We aimed to discern the involvement of the epidermal growth factor receptor (EGFR) in allergen-induced epithelial barrier impairment, as we previously observed that house dust mite (HDM) signals through EGFR. We investigated the junctional integrity of human bronchial epithelial cells using electric cell-substrate impedance sensing and immunofluorescent staining. HDM induced a rapid, transient fall in epithelial resistance, concomitant with delocalisation of E-cadherin and zona occludens (ZO)-1, and proteolytic cleavage of the latter. EGFR inhibition by AG1478 reduced the HDM-triggered decrease in epithelial resistance and improved restoration of epithelial junctions. Similarly, AG1478 increased epithelial barrier recovery upon electroporation-induced injury, although it delayed the migration phase of the wound healing response. HDM-promoted redistribution of E-cadherin was mediated via EGFR-dependent activation of protease-activated receptor (PAR)-2, while the concomitant ZO-1 degradation was PAR-2/EGFR-independent. Importantly, the fibrogenic cytokine transforming growth factor (TGF)-β prolonged HDM-induced EGFR phosphorylation and inhibited ligand-induced EGFR internalisation/degradation, which resulted in sustained E-cadherin and ZO-1 redistribution. Thus, allergen-induced, PAR-2/EGFR-mediated signalling decreases epithelial resistance and promotes junction disassembly. The TGF-β-enhanced EGFR signalling may be an important contributor to barrier dysfunction and increased epithelial vulnerability in response to HDM.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bronchi / cytology
  • Cadherins / metabolism
  • Cell Communication / immunology
  • Cell Line
  • Electroporation
  • ErbB Receptors / immunology
  • ErbB Receptors / metabolism*
  • Humans
  • Intercellular Junctions / immunology
  • Intercellular Junctions / metabolism
  • Membrane Proteins / metabolism
  • Permeability
  • Phosphoproteins / metabolism
  • Pyroglyphidae / immunology*
  • Respiratory Mucosa / cytology
  • Respiratory Mucosa / immunology*
  • Respiratory Mucosa / metabolism*
  • Signal Transduction / immunology*
  • Transforming Growth Factor beta / metabolism
  • Wound Healing / physiology
  • Zonula Occludens-1 Protein

Substances

  • Cadherins
  • Membrane Proteins
  • Phosphoproteins
  • TJP1 protein, human
  • Transforming Growth Factor beta
  • Zonula Occludens-1 Protein
  • EGFR protein, human
  • ErbB Receptors