title: Interleukin-23/Th17 pathways and inflammatory bowel disease.
abstract: The IL-23/Th17 pathway has recently been identified to play a critical role in a number of chronic inflammatory diseases including inflammatory bowel disease (IBD). The identification in IBD patients of associations in IL23R and regions that include other genes in the IL-23/Th17 pathway has highlighted the importance of proper IL-23/Th17 pathway regulation in intestinal immune homeostasis. IL-23 plays a role in CD4+ Th17 lineage cells, characterized by IL-17 secretion and the expression of the transcription factor retinoic acid-related orphan receptor (ROR)gamma tau, and in other immune and nonimmune cells. The balance between effector T cell subsets, such as Th17 cells, and CD4+ T regulatory subsets is finely regulated; dysregulation of this balance can lead to inflammation and autoimmunity. As such, the IL-23/Th17 pathway contributes to immune responses that play a role in defenses to microbial infection, as well as in the intestinal inflammation observed in both animal models of colitis and human IBD.
authors.affiliation: Department of Medicine, Digestive Diseases, Yale University, New Haven, Connecticut 06520, USA. clara.abraham@yale.edu
authors.forename: Clara
authors.initials: C
authors.lastname: Abraham
authors.forename: Judy
authors.initials: J
authors.lastname: Cho
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000276:immunology* / Q000378:metabolism*; D020381:Interleukin-17 / Q000276:immunology / Q000378:metabolism*; D053759:Interleukin-23 / Q000276:immunology / Q000378:metabolism*; D015398:Signal Transduction / Q000276:immunology*
chemical_list: D020381:Interleukin-17; D053759:Interleukin-23