Human corneal epithelial cells respond to ocular-pathogenic, but not to nonpathogenic-flagellin

Biochem Biophys Res Commun. 2006 Aug 18;347(1):238-47. doi: 10.1016/j.bbrc.2006.06.088. Epub 2006 Jun 22.

Abstract

In this study, we investigated the expression of TLR5 in human corneal epithelial cells (CEC), and the functional outcome of TLR5 triggering by flagellins of pathogenic- and nonpathogenic bacteria. Flagellins derived from Pseudomonas aeruginosa, Salmonella typhimurium, Serratia marcescense or Bacillus subtilis were used. The TLR5 protein and TLR5 specific mRNA expression was evident on human CEC. In human corneal epithelium tissues, TLR5 protein was detected at the basal and wing cells of the tissues. Ocular pathogenic bacteria, namely P. aeruginosa and S. marcescense, derived flagellin induced the significantly increased level of gene activation and IL-6 and IL-8 production. In contrast, ocular nonpathogenic S. typhimurium- and B. subtilis-derived flagellin induced neither the gene activation nor the increased production of IL-6 and IL-8 in human CEC. Human CEC would respond only to flagellin derived of ocular pathogenic bacteria, but not to those derived of ocular nonpathogenic bacteria, to generate pro-inflammatory cytokines.

MeSH terms

  • Bacterial Proteins / administration & dosage*
  • Cell Line
  • Cytokines / immunology*
  • Epithelial Cells / drug effects
  • Epithelial Cells / immunology*
  • Epithelium, Corneal / drug effects
  • Epithelium, Corneal / immunology*
  • Flagellin / administration & dosage*
  • Humans
  • Toll-Like Receptor 5 / immunology*

Substances

  • Bacterial Proteins
  • Cytokines
  • TLR5 protein, human
  • Toll-Like Receptor 5
  • Flagellin