Fig. 5.

Involvement of IL-17E in IPF. IL-17E is produced from injured epithelial cells. It acts on T cells, ILC2s, alveolar macrophages, DC and neutrophils, which can stimulate the secretion of cytokines such as IL-17E, IL-13, and TGF-β, drive lung fibrosis by mediating EMT, as well as recruit and activate lung fibroblasts. IL-17E can additionally activate a series of cell types, leading to lung inflammation, which is critical in the development of IPF. ILC2s type 2 innate lymphoid cells, IL-4 interleukin-4, IL-13 interleukin-13, TGF-β transforming growth factor-β, EMT epithelial–mesenchymal transition, ECM extracellular matrix, IPF idiopathic pulmonary fibrosis