CXCL16 and chronic obstructive pulmonary disease: Because CXCL16/CXCR6 axis is a potential candidate for CVD prediction and a target for therapeutic intervention (13), we also examined the levels of circulating CXCR6-expressing platelets and different leukocyte subsets in patients with COPD, and evaluated the implication for leukocyte adhesion to the dysfunctional arterial endothelium, a key event preceding atherogenesis.