Polymorphonuclear leucocytes consume oxygen in sputum from chronic Pseudomonas aeruginosa pneumonia in cystic fibrosis

TY - JOUR

T1 - Polymorphonuclear leucocytes consume oxygen in sputum from chronic Pseudomonas aeruginosa pneumonia in cystic fibrosis

AU - Kolpen, Mette

AU - Hansen, C. R.

AU - Bjarnsholt, Thomas

AU - Moser, C

AU - Hultqvist, Louise Dahl

AU - van Gennip, M

AU - Ciofu, O

AU - Mandsberg, L

AU - Kharazmi, A

AU - Döring, G

AU - Givskov, M

AU - Høiby, N

AU - Jensen, Peter Østrup

N1 - Keywords: Adult; Bronchi; Chronic Disease; Cystic Fibrosis; Female; Humans; Male; Middle Aged; NADPH Oxidase; Neutrophils; Oxygen Consumption; Phagocytosis; Pseudomonas Infections; Pseudomonas aeruginosa; Reactive Oxygen Species; Respiratory Burst; Sputum; Superoxides; Young Adult

PY - 2010/1/1

Y1 - 2010/1/1

N2 - Background: Chronic lung infection with Pseudomonas aeruginosa is the most severe complication for patients with cystic fibrosis (CF). This infection is characterised by endobronchial mucoid biofilms surrounded by numerous polymorphonuclear leucocytes (PMNs). The mucoid phenotype offers protection against the PMNs, which are in general assumed to mount an active respiratory burst leading to lung tissue deterioration. An ongoing respiratory burst by the PMNs has, however, not been demonstrated previously in endobronchial secretions from chronically infected patients with CF. Objective: Based on the accumulating evidence for depletion of molecular oxygen (O2) in the mucus in infected CF bronchi, it was hypothesised that the O2 depletion in the mucus in infected CF bronchi may be accelerated by the respiratory burst of the PMNs due to the reduction of O2 to the superoxide anion (O -2) by the phagocyte NADPH oxidase (Phox). Methods: Methods were established to isolate the O2 consumption by the respiratory burst from aerobic respiration in freshly expectorated sputum from chronically infected patients with CF. Results: Inhibition of the Phox with diphenylene iodonium (DPI) delayed O2 depletion, nearly abolished staining of O-2-producing PMNs with hydroethidine and inhibited the rapid luminol-enhanced chemiluminescence in sputum. Furthermore, the total O2 consumption was correlated to the concentration of PMNs in the sputum samples. Conclusion: The results demonstrate that CF sputum contains PMNs with an active consumption of O2 for O- 2 production and suggest that the respiratory burst is ongoing and causes accelerated O2 depletion due to formation of O -2 in the lungs of chronically infected patients with CF.

AB - Background: Chronic lung infection with Pseudomonas aeruginosa is the most severe complication for patients with cystic fibrosis (CF). This infection is characterised by endobronchial mucoid biofilms surrounded by numerous polymorphonuclear leucocytes (PMNs). The mucoid phenotype offers protection against the PMNs, which are in general assumed to mount an active respiratory burst leading to lung tissue deterioration. An ongoing respiratory burst by the PMNs has, however, not been demonstrated previously in endobronchial secretions from chronically infected patients with CF. Objective: Based on the accumulating evidence for depletion of molecular oxygen (O2) in the mucus in infected CF bronchi, it was hypothesised that the O2 depletion in the mucus in infected CF bronchi may be accelerated by the respiratory burst of the PMNs due to the reduction of O2 to the superoxide anion (O -2) by the phagocyte NADPH oxidase (Phox). Methods: Methods were established to isolate the O2 consumption by the respiratory burst from aerobic respiration in freshly expectorated sputum from chronically infected patients with CF. Results: Inhibition of the Phox with diphenylene iodonium (DPI) delayed O2 depletion, nearly abolished staining of O-2-producing PMNs with hydroethidine and inhibited the rapid luminol-enhanced chemiluminescence in sputum. Furthermore, the total O2 consumption was correlated to the concentration of PMNs in the sputum samples. Conclusion: The results demonstrate that CF sputum contains PMNs with an active consumption of O2 for O- 2 production and suggest that the respiratory burst is ongoing and causes accelerated O2 depletion due to formation of O -2 in the lungs of chronically infected patients with CF.

U2 - 10.1136/thx.2009.114512

DO - 10.1136/thx.2009.114512

M3 - Journal article

C2 - 19846469

SN - 0040-6376

VL - 65

SP - 57

EP - 62

JO - Thorax

JF - Thorax

IS - 1

ER -