CD19 and autoimmune thrombocytopenic purpura: To determine whether miR-133 plays an important role in Breg differentiation induced by UC-MSCs, PBMCs of ITP were cocultured with the US-MSCs transfected by the miR-133 inhibitor for 48 h, and Bregs were detected; the results exhibit that B10 cells differentiated from ITP decreased (3.21 ± 0.54% vs. 5.78 ± 0.86%) evidently compared to the nontransfected group (Figure 5(a), Supplementary 5), and correspondingly, CD19+/CD24hi/CD38hi cells differentiated from ITP decreased (2.1 ± 0.33% vs. 5.02 ± 0.57%) evidently (Figure 5(b), Supplementary 5).