IL-6 stimulates intestinal epithelial proliferation and repair after injury

PLoS One. 2014 Dec 5;9(12):e114195. doi: 10.1371/journal.pone.0114195. eCollection 2014.

IL-6 is an inflammatory cytokine known to contribute to a number of autoimmune diseases such as RA. Therapies targeting the soluble IL-6 receptor have now become effective treatments for RA. However, one unforeseen, yet rare, potential complication of anti-IL-6 therapy is bowel perforation. Yet within the intestine, IL-6 protects intestinal epithelial cells from apoptosis during prolonged inflammation.

The authors hypothesized that IL-6 may have beneficial properties in wound response/repair, surmising that the timing of the therapy with respect to injury was the critical factor that needed to be investigated. Using two murine models of bowel injury – wound by biopsy and bacterial triggered colitis, the investigators demonstrated that IL-6 is induced soon after bowel injury by multiple cell types including intraepithelial lymphocytes. Additionally, inhibition of IL-6 resulted in impaired wound healing due to decreased epithelial proliferation. Findings from these studies demonstrate a beneficial role of IL-6 for intestinal wound healing early after injury.