TGFB1 and idiopathic pulmonary fibrosis: Pro-fibrotic growth factors including transforming growth factor-beta 1 (TGF-β1) and platelet-derived growth factor (PDGF) are believed to drive the fibro-proliferative process in IPF and promote fibroblast-to-myofibroblast differentiation and collagen deposition [9, 10].