| [ Summary ] |
Inflammatory bowel diseases (IBD), ulcerative colitis (UC) and Crohn's disease (CD), are chronic intestinal disorders of unknown etiology in which, in genetically susceptible individuals, the mucosal immune system shows an aberrant response towards commensal bacteria. The gastrointestinal tract has developed ingenious mechanisms to coexist with its autologous microflora, but rapidly respond to invading pathogens and then return to homeostasis with its commensal bacteria after the pathogenic infection is cleared. If these tightly regulated homeostatic mechanisms are disturbed, chronic intestinal inflammation may be induced. Previous studies have demonstrated that some commensal bacteria are detrimental, and others have no effect or are protective. In addition, each host has a genetically determined response to detrimental or protective bacterial species. |