Indoleamine 2,3-Dioxygenase in Intestinal Immunity and Inflammation

Indoleamine 2,3-dioxygenase (IDO) is a tryptophan catabolizing enzyme that has a number Of immunoregulatory effects. It is expressed at high levels in the gastrointestinal tract, p,particularly ill the small intestine, and has been implicated in the control of intestinal inflammation. However, its, precise role in intestinal immunity is not well Understood. This review will summarize the current state of knowledge about IDO function, particularly as it pertains to inflammatory responses in the gut.