Using a previously described classification schema (Bronte et al., 2016), we quantified CD274 expression on live singlet CD33+CD11b+CD14−CD15+ cells (PMN‐MDSC, human) and found that cells from patients with ILD + PH displayed higher levels of the checkpoint protein, compared to both controls and patients with only interstitial lung disease (Figure 9a). The gene discussed is CD33; the disease is interstitial lung disease.