TH17 Cells and IL-23 in Gut Inflammation
Gut inflammation in patients with inflammatory bowel disease (IBD) has traditionally been considered to be mediated by an exaggerated TH1 response (Crohn’s disease) or an atypical TH2 response (ulcerative colitis). Recent work however, has also shown that in both types of IBD there is enhanced synthesis of cytokines made by a distinct lineage of T helper cells, termed TH17 cells. Targeting these TH17 cells may be a new avenue for the development of therapeutic strategies in IBD. Interleukin (IL)-23, a heterodimeric cytokine produced by activated antigen presenting cells, is necessary for amplifying TH17 cell responses. Paradoxically, recent studies have also shown that TH17-related cytokines have protective effects in the gut. In this chapter, we review the available data regarding the role of TH17 cells in chronic intestinal inflammation in an attempt to resolve this conundrum.
KeywordsInflammatory Bowel Dieases Ulcerative Colitis TH17 Cell Inflammatory Bowel Dieases Patient Dextran Sulfate Sodium
The authors received support for their work from the “Fondazione Umberto di Mario”, Rome, the Broad Medical Research Program Foundation (Grant No. IBD-0154R), and Giuliani Spa, Milan, Italy.
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