MPO and chronic obstructive pulmonary disease: MPO and NGAL, both neutrophil markers [14], [15], were increased with COPD disease severity and NGAL was correlated with FEV1/FVC by univariate and multivariate regression, consistent with the role of neutrophils in COPD pathogenesis [31] and recent reports that sputum neutrophilia increases with GOLD stage and is weakly associated with FEV1[32].