CCL2 and chronic obstructive pulmonary disease: n=6 independent experiments (D) CCL2, CXCL2, and CXCL8 levels in CD8+ T cells supernatants from non-smoking control subjects (CtlNS) or patients with COPD (COPD) using BioPlex (CCL2, CXCL2) or ELISA (CXCL1, 3, 5, 6, 8).