We also found that SOX9+ BC transplantation effectively blocked the progression of mouse pulmonary fibrosis manifested as fibronectin accumulation and α-SMA positive myofibroblast expansion (Phan, 2012) in the human cell-enriched area (Fig. 5A and 5B), suggesting that regenerated human lung can replace damaged tissue in mouse model. Here, SOX9 is linked to pulmonary fibrosis.