TGFB1 and pulmonary fibrosis: Experimentally, Andronegui et al. [45] have shown adenoviral treatment of mice with both Igf and Tgf-β to increase pulmonary fibrosis over mice receiving Tgf-β alone, while Yasuoka et al. [46] demonstrated adenoviral treatment with Igfbp5 to have the same effect, thus directly implicating the IGF-1 pathway in fibrosis development.