To further explore whether pretreatment with a low concentration of transforming growth factor-β1 (TGF-β1) was favourable for MSC survival in vivo, a rat model of LPS-induced ALI was generated, and the results showed that an increased number of MSCs were observed in the lung 2 weeks following transplantation, indicating that TGF-β1-treated MSCs may enhance their long-term therapeutic effect when applied to tissue repair [76]. Here, TGFB1 is linked to acute respiratory distress syndrome.