In addition, growth factors (e.g., transforming growth factor [TGF]β1, connective tissue growth factor, platelet-derived growth factor), inflammatory cytokines (e.g., interleukin [IL]-13, tumor necrosis factor α [TNFα], IL-1β), chemokines (e.g., monocyte-chemoattractant protein-1 [MCP-1]), and clotting factors (e.g., thrombin) contribute to migration, recruitment, and activation of fibroblasts during pulmonary fibrosis [9,10,11,12]. This evidence concerns the gene CCL2 and pulmonary fibrosis.