Previous studies in experimental colitis have demonstrated that MSC treatment stimulates upregulation of anti-inflammatory factors including interleukin (IL)-10, indoleamine 2,3-dioxygenase, prostaglandin E2, and transforming growth factor-β1, as well as a downregulation of pro-inflammatory mediators such as IL-1β, IL-6, IL-12, IL-17, interferon-γ and tumor necrosis factor-α [67, 92, 93]. This evidence concerns the gene IDO2 and colitis.