We used the 2% DSS‐induced acute colitis model in mice, and used 5‐aminosalicylic acid (5‐ASA) as a positive control, which mainly exerts local anti‐inflammatory effects by acting on the intestinal mucosa, to explore the role of recombinant KLK1 (rKLK1) in colitis (Figure4A). The gene discussed is KLK1; the disease is colitis.