TGFB1 and idiopathic pulmonary fibrosis: More recently, Alsafadi et al. established an ex vivo human PCLS model of early fibrosis, which requires exposure of PCLS to a combination of profibrotic growth factors and signaling molecules (TGF-β1, TNF-α, platelet-derived growth factor-AB, and lysophosphatidic acid), paving a way to study early-stage IPF pathomechanisms and evaluate novel therapies [29].