We focused on the role of E4BP4 in macrophages as a paradigm of immunoregulation of the colon because macrophages play a critical role in colitis by secreting many cytokines and regulating tissue repair, and because whole body E4BP4 knockout mice develop spontaneous colitis modulating potentially susceptible loci associated with Crohn’s disease and ulcerative colitis16,17. This evidence concerns the gene NFIL3 and Crohn disease.