For example, cultured airway epithelial cells produce IL-6 and IL-8 in response to CS exposure [14-16], and TNF-α, IL-8, MCP-1, and macrophage inflammatory protein (MIP)-1α are upregulated in the bronchiolar epithelium of subjects with COPD [17-19]. This evidence concerns the gene CXCL8 and chronic obstructive pulmonary disease.