TGFB1 and pulmonary fibrosis: Activation of TGF-β1 via αv integrins is central to fibrogenesis, with both genetic models using integrin β1−/− and integrin β6−/− mice as well as anti-β6 mAbs ameliorating bleomycin-induced lung fibrosis (17, 18, 19, 20, 21).