Figure 4.

Single-cell RNA-Seq analysis reveals distinct contributions of individual cell populations to pathways implicated in the pathogenesis of pulmonary fibrosis. (A) Expression of selected Wnt pathway, Notch pathway, and epithelial-to-mesenchymal transition–related genes is shown in fibroblasts, endothelial cells, alveolar type I cells, alveolar type II cells, ciliated cells, club cells, basal cells, and macrophages, separated by donor (blue) or pulmonary fibrosis (red) origin. Dot size corresponds to the percentage of cells in the cluster expressing a gene, and dot color corresponds to the average expression level for the gene in the cluster. (B) Violin plots of WNT2, WNT7B, AXIN2, and RSPO3 expression are shown, suggesting the presence of distinct Wnt-expressor and Wnt-responder cell populations in the human lung. AT 1/2 = alveolar type I/II; EMT = epithelial to mesenchymal transition.