CCL21 and inflammatory bowel disease: Controlled clinical studies have also shown that CCL20, CXCL10, CXCL16, and CCL25 are more highly expressed in inflamed intestinal tissues than in normal intestinal tissues (31), and IBD patients have a significant increase in an array of chemokines including CCL25, CCL23, CXCL5, CXCL13, CXCL10, CXCL11, and CCL21 in IBD patients as compared to normal healthy donors (11, 32).