Its main roles include (1) providing chemotactic effects on monocytes and macrophages and promoting the expression of cytokines related to pulmonary fibrosis such as TNF-α, IL-1, IL-6, and PDGF [66]; (2) inducing epithelial-mesenchymal transition in alveolar epithelial cells [61, 67]; (3) promoting the migration, proliferation, differentiation of fibroblasts, and deposition of extracellular matrix [68]; and (4) protecting the stability of the extracellular matrix without degradation. Here, IL6 is linked to pulmonary fibrosis.