[The role of neutrophils and interleukin-8 in pathogenesis of asthma].
OBJECTIVE
To investigate the role of neutrophils and interleukin-8 (IL-8) in pathogenesis of asthma.


METHODS
Pulmonary function and bronchial provocation test were performed to identify and evaluate asthma. Superoxide anion O(2)(-.) generation of peripheral blood neutrophils, IL-8 and malondialhyde (MDA) levels in plasma and induced sputum were measured.


RESULTS
The O(2)(-.) generation [(20.9 +/- 5.1) nmol] of peripheral blood neutrophils from moderate-severe asthmatics were significantly higher than that [(15.2 +/- 4.2) nmol] from mild asthmatics (P < 0.01), in which that was still significantly higher than that [(11.3 +/- 2.4) nmol] from normal subjects (P < 0.05). The O(2)(-.) generation of peripheral blood neutrophils had significantly negative correlation with PD(20)FEV(1) (r = -0.693, P < 0.05). The levels of IL-8 [(585 +/- 75) ng/L, (791 +/- 103) ng/L] and MDA levels [(6.3 +/- 1.6) mmol/L, (21.8 +/- 6.3) mmol/L] in plasma and induced sputum from unstable asthmatics were higher than those [(227 +/- 54) ng/L, (322 +/- 95) ng/L and (5.4 +/- 1.0) mmol/L, (15.1 +/- 5.6) mmol/L] from stable asthmatics (P < 0.01), more over, in the latter group, they were still significantly higher than those (188 +/- 46) ng/L, (224 +/- 51) ng/L and [(4.1 +/- 0.4) mmol/L, (9.5 +/- 4.2) mmol/L] from normal subjects (P < 0.05). The levels of MDA in the induced sputum from stable asthmatics showed a negative correlation with PD(20)FEV(1) (r = -0.708, P < 0.01). The levels of IL-8 in the induced sputum showed a positive correlation with percentage of neutrophils in the induced sputum (r = 0.838, P < 0.01).


CONCLUSIONS
IL-8 and oxygen free radicals generated by neutrophils might participate in development of airway inflammation and airway hyperresponsiveness in asthma.
Zhang
H
H
Department of Respiratory Disease, Peking Union Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China.
Lin
Y
Y
Ding
C
C
D000328:Adult; D001249:Asthma / Q000097:blood / Q000209:etiology / Q000276:immunology*; D005260:Female; D006801:Humans; D016209:Interleukin-8 / Q000032:analysis / Q000276:immunology*; D008168:Lung / Q000503:physiopathology; D008297:Male; D008315:Malondialdehyde / Q000032:analysis; D009504:Neutrophils / Q000166:cytology / Q000276:immunology*; D013183:Sputum / Q000276:immunology; D013481:Superoxides / Q000378:metabolism
D016209:Interleukin-8; D013481:Superoxides; D008315:Malondialdehyde