Interestingly, upregulation of the same gene set, including CD151, SPATA1, DEFA4, SERPINE3, FBXO3, and SART3, was linearly associated with elevated counts of macrophages and lymphocytes and conversely decreased number of neutrophils in sputum from COPD patients. This evidence concerns the gene DEFA4 and chronic obstructive pulmonary disease.