Inducible and constitutive beta-defensins are differentially expressed in Crohn's disease and ulcerative colitis

Inflamm Bowel Dis. 2003 Jul;9(4):215-23. doi: 10.1097/00054725-200307000-00001.


Antimicrobial peptides such as defensins provide nonspecific mucosal defense against a multitude of microorganisms. Recently, it has been shown that luminal bacteria may invade the mucosa in inflammatory bowel diseases, suggesting a defect in innate mucosal immunity. The aim of this study was to investigate the expression of human beta-defensins (HBD) in controls, Crohn's disease (CD), ulcerative colitis (UC), and unspecific inflammation. Up to 4 biopsies were taken from 103 patients (33 controls, 24 with Crohn's disease, 36 with ulcerative colitis, 10 with unspecific colitis). Mucosal mRNA was measured using real-time fluorescence temperature cycler reverse-transcription polymerase chain reaction with primers for HBD-1, HBD-2, HBD-3, tumor necrosis factor alpha, and interleukin 8. Mucosal HBD-1 expression was marginally decreased in both CD and UC. HBD-2 was increased exclusively in UC but not in CD. The expression of the novel defensin HBD-3 was strongly correlated with HBD-2 and also raised predominantly in UC. The expression of both inducible beta-defensins was enhanced in the state of inflammation. Expression of HBD-2 showed a weak correlation with interleukin 8 only in inflamed CD biopsies but not with tumor necrosis factor alpha. The missing induction of both inducible beta-defensins in CD as compared with UC may cause a defect in barrier function that predisposes to bacterial invasion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Bacteria / pathogenicity
  • Biopsy
  • Child
  • Colitis, Ulcerative / immunology*
  • Colitis, Ulcerative / microbiology
  • Colitis, Ulcerative / physiopathology*
  • Crohn Disease / immunology*
  • Crohn Disease / microbiology
  • Crohn Disease / physiopathology*
  • Female
  • Gene Expression Regulation
  • Humans
  • Inflammation
  • Male
  • Middle Aged
  • RNA, Messenger / analysis
  • Reverse Transcriptase Polymerase Chain Reaction
  • beta-Defensins / biosynthesis*


  • RNA, Messenger
  • beta-Defensins