TGFB1 and pulmonary fibrosis: TGF-β1 is one of the most notable and important profibrogenic factors that accelerates epithelial-mesenchymal transition, promotes fibroblast proliferation, increases extracellular matrix deposition, activates profibrotic pathways (Woodcock et al., 2019) and causes lung fibrosis (Saito, Horie & Nagase, 2018).