Upregulation of CXCL10, the ligand of the chemokine receptor CXCR3 found on macrophages, has been observed in the bronchiolar epithelium of patients with Chronic Obstructive Pulmonary Disease (COPD) compared to non-smokers or smokers with normal lung function (Saetta et al., 2002). Here, CXCL10 is linked to chronic obstructive pulmonary disease.