TGFB1 and pulmonary fibrosis: Finally, a study by Liu et al. (119) showed that the administration of the supernatant from a bone marrow-derived hMSC culture, which expressed higher level of TGF-β1, has a better therapeutic efficacy in improving the survival rate and reducing pulmonary inflammation and fibrosis in a bleomycin-induced pulmonary fibrosis mouse model when compared to umbilical cord-derived hMSCs, which secrete a lower level of TGF-β1.