CXCL12 and colitis: To identify the effect of the SDF-1-pretreated ERCs in DSS-induced colitis in mice, we investigated the percentage of Th2 through double-positive staining of the anti-mouse CD4 and IL-4 antibodies and Tregs through triple-positive staining of the anti-mouse CD4, CD25, and Foxp3 antibodies in the splenocytes of each group by flow cytometry.