Activation of Toll-like receptors 2 and 4 in Aspergillus fumigatus keratitis

Innate Immun. 2009 Jun;15(3):155-68. doi: 10.1177/1753425908101521.

Abstract

Toll-like receptor (TLR) 2 and TLR4 are major receptors of Aspergillus fumigatus. Aspergillus fumigatus signaling in cornea induces the production of many pro-inflammatory molecules. In this study, we have shown that exposure of telomerase-immortalized human corneal epithelial cells (HCECs) to A. fumigatus antigens resulted in up-regulation of TLR2 and TLR4, and release of IL-1beta and IL-10 in HCECs, effects that could be inhibited by treatment with TLR2, and TLR4 antibodies. In addition, the A. fumigatus antigens-induced production of IL-1beta and IL-10 in supernatants of corneal epithelial cells was also attenuated by NF-kappaB inhibitor. Aspergillus fumigatus keratitis developed in Wistar rats, as evidenced by high SLE scores, influx of polymorphonuclear leukocytes (PMNs), activation of TLR2 and TLR4, and production of IL-1beta and IL-10 over controls. These findings indicate that the cornea has functional TLR2 and TLR4, and activation of TLR2 and TLR4 through NF-kappaB may contribute to pathogenesis of keratomycosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Fungal / immunology
  • Antigens, Fungal / metabolism
  • Aspergillosis / immunology*
  • Aspergillosis / pathology
  • Aspergillus fumigatus*
  • Cell Line
  • Epithelium, Corneal / immunology*
  • Epithelium, Corneal / metabolism
  • Epithelium, Corneal / microbiology
  • Female
  • Humans
  • Interleukin-10 / immunology
  • Interleukin-10 / metabolism
  • Interleukin-1beta / immunology
  • Interleukin-1beta / metabolism
  • Keratitis / immunology*
  • Keratitis / microbiology
  • Keratitis / pathology
  • NF-kappa B / immunology
  • NF-kappa B / metabolism
  • Rats
  • Rats, Wistar
  • Toll-Like Receptor 2 / agonists
  • Toll-Like Receptor 2 / genetics
  • Toll-Like Receptor 2 / immunology*
  • Toll-Like Receptor 4 / agonists
  • Toll-Like Receptor 4 / genetics
  • Toll-Like Receptor 4 / immunology*
  • Up-Regulation / immunology

Substances

  • Antigens, Fungal
  • Interleukin-1beta
  • NF-kappa B
  • Toll-Like Receptor 2
  • Toll-Like Receptor 4
  • Interleukin-10