SMAD3 and idiopathic pulmonary fibrosis: These include TGFβ/SMAD3-targeted genes Col1a2, Fn1 and Vim, Keratin 14 (Krt14, which is absent in distal airways of healthy lungs, but increased specifically in distal airways and alveolar regions of idiopathic pulmonary fibrosis (IPF) lungs) (93), Nodal growth differentiation factor (TGFβ super family protein, activator of SMAD family transcription factors), SRY-box containing gene 10 (Sox10, transcription factors involved in development and in cell fate outcomes).