MUC5AC and idiopathic pulmonary fibrosis: Notably, three of the six IPF cell makers (KRT5, NGFR, MUC5B) showed significantly up-regulation in advanced-stage of IPF and the other two makers (SCGB1A1, MUC5AC) were marginally significantly up-expressed in advanced-stage of IPF compared with early-stage of IPF (Supplementary Fig. S5).