Microbial compounds induce the expression of pro-inflammatory cytokines, chemokines and human beta-defensin-2 in vaginal epithelial cells

Microbes Infect. 2005 Jul;7(9-10):1117-27. doi: 10.1016/j.micinf.2005.03.016. Epub 2005 Apr 19.

Abstract

Vaginal epithelium has a powerful innate immune system that protects the female reproductive organs from bacterial and fungal infections. In the present study, we aimed to explore whether the Toll-like receptor (TLR) signaling pathway and the induction of pro-inflammatory cytokines and antimicrobial peptides could contribute to the protection against pathogenic microorganisms in vaginal epithelia, using an immortalized vaginal epithelial cell line PK E6/E7 as a model. We found that TLR2 and TLR4 receptors are expressed in vivo in the vaginal epithelia and in vitro in PK E6/E7 vaginal epithelial cell line. The Gram-negative cell wall compound lipopolysaccharide (LPS), the Gram-positive compound peptidoglycan (PGN), heat-killed Candida albicans and zymosan significantly (P<0.05) induced the expression of pro-inflammatory cytokines and chemokines such as TNF-alpha and IL-8/CXCL8 in vaginal epithelial cells. Furthermore, the expression and production of human beta-defensin-2 (hBD2), an antimicrobial peptide with chemotactic functions, was also up-regulated in PK E6/E7 cells after treatment with LPS, PGN or C. albicans. Treatment of vaginal epithelial cells with microbial compounds induced the activation and nuclear translocation of NF-kappaB transcription factor, a key element of innate and adaptive immune responses. In our work, we provide evidence that microbial compounds induce the production of pro-inflammatory cytokines, chemokines and antimicrobial peptides in vaginal epithelial cells. In vivo, vaginal epithelial cell-derived inflammatory mediators and antimicrobial peptides may play important roles in vaginal immune responses and in the elimination of pathogens from the female reproductive tract.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Candida albicans / immunology
  • Cell Line
  • Chemokines / biosynthesis*
  • Cytokines / biosynthesis*
  • Epithelial Cells / drug effects
  • Epithelial Cells / immunology*
  • Female
  • Gene Expression
  • Humans
  • Immunohistochemistry
  • Lipopolysaccharides / immunology
  • NF-kappa B / analysis
  • Peptidoglycan / immunology
  • RNA, Messenger / analysis
  • Reverse Transcriptase Polymerase Chain Reaction
  • Toll-Like Receptor 2 / analysis
  • Toll-Like Receptor 2 / genetics
  • Toll-Like Receptor 4 / analysis
  • Toll-Like Receptor 4 / genetics
  • Vagina / drug effects
  • Vagina / immunology*
  • Zymosan / immunology
  • beta-Defensins / biosynthesis*

Substances

  • Chemokines
  • Cytokines
  • DEFB4A protein, human
  • Lipopolysaccharides
  • NF-kappa B
  • Peptidoglycan
  • RNA, Messenger
  • TLR2 protein, human
  • TLR4 protein, human
  • Toll-Like Receptor 2
  • Toll-Like Receptor 4
  • beta-Defensins
  • Zymosan