Innate immunity in inflammatory bowel disease

World J Gastroenterol. 2007 Nov 14;13(42):5577-80. doi: 10.3748/wjg.v13.i42.5577.


The human intestinal tract is home to an enormous bacterial flora. The host defense against microorganisms can be divided into innate and adaptive immunity. The former is the most immediate line of response to immunologic challenges presented by bacteria, viruses, and fungi. The mucosal immune system has evolved to balance the need to respond to pathogens while co-existing with commensal bacteria and food antigens. In inflammatory bowel disease (IBD), this hyporesponsiveness or tolerance breaks down and inflammation supervenes driven by the intestinal microbial flora. Bacteria contain compounds and are recognized by a variety of receptors, including Toll-like receptors (TLRs) and NODs (a family of intracellular bacterial sensors) and are potent stimuli of innate immune responses. Several mutations in these receptors have been associated with development of IBD.

Publication types

  • Review

MeSH terms

  • Crohn Disease / immunology
  • Humans
  • Immunity, Innate*
  • Inflammatory Bowel Diseases / immunology*
  • Nod1 Signaling Adaptor Protein / physiology*
  • Nod2 Signaling Adaptor Protein / physiology*
  • Toll-Like Receptors / physiology*


  • NOD1 protein, human
  • NOD2 protein, human
  • Nod1 Signaling Adaptor Protein
  • Nod2 Signaling Adaptor Protein
  • Toll-Like Receptors