ACTA1 and Bloom syndrome: Western blotting results in vivo showed that LR-MSCs could not effectively decrease the levels of α-SMA and Collagen I in the lungs of BLM mice, while LR-MSCs (LV-SENP1-shRNA) downregulated the levels of α-SMA and Collagen I in the lung of BLM mice significantly (Fig. 6B).