PT - JOURNAL ARTICLE AU - Kuroki, Misuzu AU - Noguchi, Yuji AU - Shimono, Michihide AU - Tomono, Kazunori AU - Tashiro, Takayoshi AU - Obata, Yuichi AU - Nakayama, Eiichi AU - Kohno, Shigeru TI - Repression of Bleomycin-Induced Pneumopathy by TNF AID - 10.4049/jimmunol.170.1.567 DP - 2003 Jan 01 TA - The Journal of Immunology PG - 567--574 VI - 170 IP - 1 4099 - http://www.jimmunol.org/content/170/1/567.short 4100 - http://www.jimmunol.org/content/170/1/567.full SO - J. Immunol.2003 Jan 01; 170 AB - Idiopathic pulmonary fibrosis is a chronic inflammatory lung disease with interstitial fibrosis. As a potent proinflammatory cytokine, TNF has been suggested to play critical roles in the pathogenesis of the human disease and its animal model, bleomycin-induced pneumopathy. However, studies using TNF-deficient mice have demonstrated that TNF also has an anti-inflammatory function. To determine the role of TNF in pulmonary inflammation induced by bleomycin, we injected bleomycin intratracheally into TNF-deficient mice. In this study, we demonstrated persistent and intense inflammation in TNF-deficient mice due to reduced apoptosis of inflammatory cells. We also showed that in TNF-deficient mice, challenge via airways with murine, but not human rTNF, efficiently eliminated inflammatory cells from the bronchoalveolar space by apoptosis, and thus promoted tissue repair of damaged lungs. Contrary to previous reports that showed that TNF was a central mediator of pulmonary inflammation, we have demonstrated that TNF is essential for repressing pulmonary inflammation in bleomycin-induced pneumopathy.