The rates of CD44 expression of CTD‐ILD‐LFs, BOS‐LFs, A549, Calu‐3, and 16HBE are reported in Figure 2B, which shows that cells recovered from interstitial lung disease (ILD) cells and A549 cells, a type II alveolar epithelial cell line derived from lung adenocarcinoma, express CD44 at the highest rates.[21, 22]. The gene discussed is CD44; the disease is lung adenocarcinoma.