| First Author | Mi S | Year | 2011 |
| Journal | J Immunol | Volume | 187 |
| Issue | 6 | Pages | 3003-14 |
| PubMed ID | 21841134 | Mgi Jnum | J:179251 |
| Mgi Id | MGI:5301505 | Doi | 10.4049/jimmunol.1004081 |
| Citation | Mi S, et al. (2011) Blocking IL-17A promotes the resolution of pulmonary inflammation and fibrosis via TGF-beta1-dependent and -independent mechanisms. J Immunol 187(6):3003-14 |
| abstractText | Pulmonary fibrosis is the pathologic basis for a variety of incurable human chronic lung diseases. IL-17A, a glycoprotein secreted from IL-17-producing cells, has recently been shown to be a proinflammatory cytokine involved in chronic inflammation and autoimmune disease. In this study, we report that IL-17A increased the synthesis and secretion of collagen and promoted the epithelial-mesenchymal transition in alveolar epithelial cells in a TGF-beta1-dependent manner. Using in vivo fibrotic models, we found IL-17A expression to be elevated and IL-17A-associated signaling pathways to be activated in fibrotic lung tissues. Neutralization of IL-17A in vivo promoted the resolution of bleomycin-induced acute inflammation, attenuated pulmonary fibrosis, and increased survival. Additionally, IL-17A antagonism inhibited silica-induced chronic inflammation and pulmonary fibrosis. Targeting IL-17A resulted in a shift of the suppressive immune response in fibrotic lung tissue toward a Th1-type immune response, and it effectively induced autophagy, which promoted the autophagic degradation of collagen and autophagy-associated cell death. Moreover, IL-17A was found to attenuate the starvation-induced autophagy, and autophagy modulators regulated collagen degradation in the alveolar epithelial cells in a TGF-beta1-independent manner. Administration of 3-methylamphetamine, an autophagy inhibitor, reversed the therapeutic efficacy of IL-17A antagonism in pulmonary fibrosis. Our studies indicate that IL-17A participates in the development and progression of pulmonary fibrosis in both TGF-beta1-dependent and -independent manners and that the components of the IL-17A signaling pathway are potential therapeutic targets for the treatment of fibroproliferative lung diseases. |
