It is generally acknowledged that STAT3 affects the production of pro-inflammatory cytokines by binding and activating the NF-κB subunit RelA/p65 in the nucleus (20, 21) However, as STAT3 deficiency in macrophages and neutrophils causes chronic colitis in mice, it is also assumed that STAT3 is a negative regulator of inflammation (22). Here, STAT3 is linked to Chronic colitis.