IL6 and chronic obstructive pulmonary disease: The first pattern is described regarding the levels of IL-1β, TNF-α, IL-6, IFN-γ, MCP-1/CCL2, GM-CSF, and KC/CXCL1 for which we noted a consistent and significant increase of ~2-fold in the COPD group in comparison with the control group; only in the case of KC/CXCL1 a lower although still significant increase of ~1.4-fold was observed.