CADM1 and idiopathic interstitial pneumonia: A scatter plot of all cases and Spearman correlation analyses revealed that the full-length CADM1 level per epithelial cell was inversely correlated with the α-shedding rate (Fig. 1d), suggesting that increased α-shedding contributed to the decreased levels of full-length CADM1 in lung epithelial cells of patients with IIP.