A set of single-cell data from IPF patients (GSE135893) was obtained, and analysis of this dataset revealed significantly decreased expression of YAP1 in AT1 and AT2 cells from IPF patients compared with those from control donors, while the expression of YAP1 was significantly increased in lung fibroblasts, in accordance with our previous finding that the upregulation of YAP1 in lung fibroblasts promoted pulmonary fibrosis (Fig. 1a, b). This evidence concerns the gene YAP1 and idiopathic pulmonary fibrosis.