Elevated MPO levels associated with increased morbidityMPO levels are higher in the stool of patients with active IBDMPO impairs resolution of mucosal injury via suppression of IEC migration and proliferationMPO inhibition limits severity of colitisMPO released on NETs exacerbates colitis, promotes tissue damage, and is positively correlated with severity of Crohn’s disease. Here, MPO is linked to colitis.