Neutrophil phagocytic activity in AECOPD

Abstract

Background: Neutrophils are the major inflammatory cells in pathogenesis of chronic obstructive pulmonary disease (COPD). It is known that phagocytic activity of these cells is decreased during stable COPD (SCOPD). Otherwise, it is unknown how neutrophils act in acute exacerbation of COPD (AECOPD). Aim: To investigate neutrophils phagocytic activity in AECOPD. Methods: 10 patients with SCOPD, 7 with AECOPD and 10 healthy individuals (HI) were studied. Neutrophils were isolated from peripheral blood by high-density gradient Ficoll. Phagocytosis was investigated using different concentrations of FITC labeled S. aureus bacteria (1-167 bacteria/neutrophil (b/n)). Phagocytic activity was analyzed using flow cytometer assessing the cellular immunofluorescence intensity in neutrophil population. Results: Neutrophil phagocytic activity was decreased in patients with AECOPD in comparison with SCOPD and HI. The highest phagocytosis was obtained using 167 b/n concentration in AECOPD and SCOPD groups (6.52±2.5-fold and 8.84±1.8-fold), but phagocytic activity was lower compared with HI (13.5±2.2- fold) (p<0.05). Conclusion: Our results shows that neutrophils phagocytosis is decreased during AECOPD.