However, the median serum KL-6 level was not different among patients with DILD, RP, and AE-ILD (353.7 vs. 281.9 vs. 761.5; p = 0.178), although patients with AE-ILD had the highest median serum KL-6 level at baseline (see Supplementary Fig. S2b online). Here, MUC1 is linked to interstitial lung disease.