Comparative expression of discoidin domain receptors (DDRs) between healthy lung tissues and those from different types of interstitial lung disease (ILD): a) idiopathic pulmonary fibrosis (IPF) and b) non-IPF ILD. The disease-induced elevation of DDR2 dram... Comparative expression of discoidin domain receptors (DDRs) between healthy lung tissues and those from different types of interstitial lung disease (ILD): a) idiopathic pulmonary fibrosis (IPF) and b) non-IPF ILD. The disease-induced elevation of DDR2 dramatically exceeds that of DDR1 in both IPF and non-IPF ILD. Bar graphs represent the mean±sd of three individual experiments. Huan Bian et al. ERJ Open Res 2018;4:00138-2016 ©2018 by European Respiratory Society