CXCL12 and autoimmune thrombocytopenic purpura: UC-MSCs could effectively enhance the decreased proportion of Bregs from ITP; different doses of SDF-1α have different effects on the proliferation, apoptosis, and survival of UC-MSCs, and at appropriate concentrations, SDF-1α may further promote the proliferating and survival ability of UC-MSCs and improve the production of Bregs induced by UC-MSCs through controlling the miRNA-133 expression in the exosomes, which displays a novel solution in improving the immunoregulatory capacity of MSCs for ITP management.