Differential regulation of porcine beta-defensins 1 and 2 upon Salmonella infection in the intestinal epithelial cell line IPI-2I

Vet Immunol Immunopathol. 2006 Nov 15;114(1-2):94-102. doi: 10.1016/j.vetimm.2006.07.012. Epub 2006 Aug 30.

Abstract

Intestinal epithelial cells represent the first line of defence against pathogenic bacteria in the lumen of the gut. Besides acting as a physical barrier, epithelial cells orchestrate the immune response through the production of several innate immune mediator molecules including beta-defensins. Here, we establish the porcine intestinal cell line IPI-2I as a new model system to test the regulation of porcine beta-defensins 1 and 2. Gene expression of both defensins was highly upregulated by foetal calf serum components in normal growth medium. In serum-free medium, baseline expression remained low, but pBD-2 gene expression was increased 10-fold upon infection with Salmonella Typhimurium. Arcobacter cryaerophilus and Salmonella Enteritidis, pathogenic bacteria with comparable adhesion and invasion characteristics, failed to increase pBD-2 mRNA levels. Heat killed or colistin-treated Salmonella Typhimurium had no effect, showing that the upregulation of pBD-2 was dependent on the viability of the Salmonella Typhimurium. Gene expression of pBD-1 was regulated differently since an increase in pBD-1 mRNA was observed by Salmonella Enteritidis infection. We conclude that the IPI-2I cells can serve as a new model to study porcine beta-defensin regulation and that pBD-1 and pBD-2 are differentially regulated in this cell line.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacterial Adhesion / immunology
  • Cell Line
  • Enzyme-Linked Immunosorbent Assay / veterinary
  • Epithelial Cells
  • Gene Expression Regulation / immunology*
  • Interleukin-8 / immunology
  • Intestinal Diseases / genetics
  • Intestinal Diseases / immunology
  • Intestinal Diseases / microbiology
  • Intestinal Diseases / veterinary*
  • Microscopy, Electron, Scanning / veterinary
  • RNA / chemistry
  • RNA / genetics
  • Reverse Transcriptase Polymerase Chain Reaction / veterinary
  • Salmonella Infections, Animal / genetics
  • Salmonella Infections, Animal / immunology*
  • Salmonella Infections, Animal / microbiology
  • Salmonella typhimurium / immunology*
  • Salmonella typhimurium / ultrastructure
  • Statistics, Nonparametric
  • Swine
  • Swine Diseases / genetics
  • Swine Diseases / immunology
  • Swine Diseases / microbiology*
  • beta-Defensins / biosynthesis*
  • beta-Defensins / genetics
  • beta-Defensins / immunology

Substances

  • Interleukin-8
  • beta-Defensins
  • RNA