Transplantation of amnion-derived MSCs (AMSCs) and conditioned medium (CM) via enema in a TNBS-induced colitis rat model provided a significant improvement in endoscopic score, a significant decrease in infiltration of neutrophils and monocytes/macrophages, and a decrease in expression levels of TNF-α, CXCL1, and CCL2, leading to a significant improvement in colitis injuries [43]. Here, CCL2 is linked to colitis.