CXCL9 and chronic obstructive pulmonary disease: Taken together our analysis of COPD transplant lungs and corresponding plasma reveals a highly aberrant immune environment characterized by strong lymphocytic inflammation, which corresponds to increased levels of lymphocytic chemoattractants CCL5, CXCL9 and CXCL10 in the lung, and increased CCL5 and CXCL5 in the circulation, potentially indicating continuous cell recruitment and retention in the lungs.