Role of nasal interleukin-8 in neutrophil recruitment and activation in children with virus-induced asthma.
Neutrophil infiltration is a major feature in the pathogenesis of the common cold, and respiratory viral infection is the major cause of asthma exacerbations. The factors regulating the neutrophil influx are unknown. Interleukin-8 (IL-8) is a potent neutrophil chemoattractant, which has been implicated in several inflammatory diseases. In this study, we investigated the presence of IL-8 chemokine in the nasal aspirates of asthmatic children (n = 12) in whom asthma was precipitated by proven viral infection. There were increased IL-8 levels in nasal aspirates from children during the virus-induced asthma exacerbations compared with samples from the same children when they had been asymptomatic for 2 wk (medians 863 and < 20 pg/ml, respectively, p < 0.01). Biological relevance was shown in that IL-8 levels correlate with increased nasal aspirate neutrophil myeloperoxidase levels and there was also a correlation between myeloperoxidase levels and upper respiratory symptom severity. Furthermore, we purified IL-8 from these samples, and demonstrated biological neutrophil chemotactic activity. These are the first in vivo data to suggest an important role for IL-8 in neutrophil influx in proven upper respiratory viral infection associated with asthma exacerbations. We suggest that IL-8 might provide a target for therapeutic intervention in virus-induced respiratory diseases.
Teran
L M
LM
University Medicine, University of Southampton, United Kingdom.
Johnston
S L
SL
Schröder
J M
JM
Church
M K
MK
Holgate
S T
ST
D001249:Asthma / Q000276:immunology / Q000821:virology*; D002634:Chemotaxis, Leukocyte; D002648:Child; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D016209:Interleukin-8 / Q000032:analysis / Q000502:physiology*; D008297:Male; D009297:Nasal Mucosa / Q000378:metabolism; D018375:Neutrophil Activation / Q000276:immunology*; D009504:Neutrophils / Q000201:enzymology / Q000276:immunology*; D009195:Peroxidase / Q000032:analysis; D012141:Respiratory Tract Infections / Q000150:complications* / Q000276:immunology / Q000821:virology; D014777:Virus Diseases / Q000150:complications* / Q000276:immunology
D016209:Interleukin-8; D009195:Peroxidase