Increased levels of activated neutrophils in the colon are a hallmark of active IBD,16 and neutrophil proteins calprotectin, lipocalin, and myeloperoxidase (Mpo) are used as disease biomarkers.36 We found increased neutrophils in the colon of LTβRΔN mice, but we did not find evidence for increased generation and mobilization of neutrophils at steady state or homing to the intestine in DSS-treated mice. Here, MPO is linked to inflammatory bowel disease.