Differential regulation of porcine beta-defensins 1 and 2 upon Salmonella infection in the intestinal epithelial cell line IPI-2I.
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.
Veldhuizen
Edwin J A
EJ
Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, 3508 TD Utrecht, The Netherlands. E.Veldhuizen@vet.uu.nl
Hendriks
Henno G C J M
HG
Hogenkamp
Astrid
A
van Dijk
Albert
A
Gaastra
Wim
W
Tooten
Peter C J
PC
Haagsman
Henk P
HP
D000818:Animals; D001422:Bacterial Adhesion / Q000276:immunology; D002460:Cell Line; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D004847:Epithelial Cells; D005786:Gene Expression Regulation / Q000276:immunology*; D016209:Interleukin-8 / Q000276:immunology; D007410:Intestinal Diseases / Q000235:genetics / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D008855:Microscopy, Electron, Scanning / Q000662:veterinary; D012313:RNA / Q000737:chemistry / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D012481:Salmonella Infections, Animal / Q000235:genetics / Q000276:immunology* / Q000382:microbiology; D012486:Salmonella typhimurium / Q000276:immunology* / Q000648:ultrastructure; D018709:Statistics, Nonparametric; D013552:Swine; D013553:Swine Diseases / Q000235:genetics / Q000276:immunology / Q000382:microbiology*; D023083:beta-Defensins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology
D016209:Interleukin-8; D023083:beta-Defensins; D012313:RNA