Gut microbiome and inflammatory bowel disease

Normal flora is the term used to describe the various bacteria and fungi that are permanent residents of certain body sites, especially the skin, oropharynx, colon, and vagina. The normal flora organisms are often referred to as commensals. Commensals are organisms that derive benefit from another host but do not damage that host.(1) The intestinal microbiota is composed of 1013-14 microorganisms (Fig1). The gastrointestinal (GI) tract contains both “friendly” bugs, such as Gram-positive Lactobacilli and Bifidobacteria dominate (> 85% of total bacteria), and potential pathogenic bacteria.(2) The intestinal microbiota plays important role in certain autoimmune diseases such as the inflammatory bowel diseases, Crohn’s disease and ulcerative colitis