Wu X, Xu L, Cheng Q, et al. - Researchers assessed whether serum soluble programmed death ligand 1(sPD-L1) levels associated with the development of interstitial lung disease (ILD) in patients with rheumatoid arthritis (RA). Via enzyme-linked immunosorbent assay, serum sPD-L1 were assessed. sPD-L1 levels were compared in RA with ILD, RA without ILD and healthy controls. Via logistic regression analysis, correlations between ILD and various markers including sPD-L1 and confounding factors were evaluated. Diagnostic values of sPD-L1 for the presence of ILD were investigated. Applying receiver operating characteristics curve analysis, diagnostic values of sPD-L1 for the presence of ILD were analyzed. There were significant improvement of serum sPD-L1 levels in RA patients with ILD. There were an association between aIncreased sPD-L1 levels and the presence of ILD.