TNF-alpha upregulates the expression of transforming growth factor-beta 1 in vitro and in an animal model, resulting in chronic inflammation and lung fibrosis [93]; but, on the contrary, the TNF-alpha supplementation ameliorates the lung function and architecture in TNF-alpha (−/−) mice with bleomycin-induced lung fibrosis [95]. Here, TGFB1 is linked to pulmonary fibrosis.