We detected significantly increased concentrations of the neutrophil granule proteins NE (Figure 7A), MPO (Figure 7B), and NGAL (Figure 7C) in patients experiencing COPD exacerbation versus healthy control plasma (derived from an independent cohort 3) (Table E3), although there was no difference in the plasma content of resistin (Figure 7D). This evidence concerns the gene LCN2 and chronic obstructive pulmonary disease.