Our current study not only confirmed that BLM‐induced pulmonary fibrosis is attenuated in Dpp4 KO mice (Soare et al., 2020), but it expands upon prior work by suggesting that the mechanisms responsible for these effects in vivo involve a decrease in fibroblasts and myofibroblasts, Tgfb downregulation in the lungs, and inhibitory effects on lung fibroblast activation. Here, TGFB1 is linked to pulmonary fibrosis.