TGFB1 and pulmonary fibrosis: In the pseudostratified monocultures of the HBECs we observed the TGF-β1–induced EMT program described in lung fibrosis leading to the enhancement of the expression of mesenchymal genes as ACTA2, CDH2 and EMT-related transcription factors SNAI1 and SNAIL2 [10, 31, 40, 54, 55].