CD274 and idiopathic pulmonary fibrosis: Median PD-L1% expression was significantly lower in lymphocytes of patients with IPF compared to lung cancer (IPF: 0.0, 95% CI: 0.0 to 0.5 vs. lung cancer: 1.3, 95% CI: 0.0 to 34.8, p = 0.04), (Fig. 3, Panel B).