چکیده (انگلیسی):

Background: Little information is available regarding eosinophil activation and cytokine profiles in
relation to age in virus-induced bronchial asthma. We therefore explored the association between age,
respiratory viruses, serum eosinophil cationic protein (ECP), and cytokines/chemokines in acute exacerbations
of childhood asthma.
Methods: We investigated viruses in nasal secretions from 88 patients with acute exacerbation of
childhood asthma by using antigen detection kits and/or RT-PCR, followed by direct DNA sequencing
analysis. We also measured peripheral eosinophil counts, and the serum levels of ECP and 27 types of
cytokines/chemokines in 71 virus-induced acute asthma cases and 13 controls.
Results: Viruses were detected in 71(80.7%) of the 88 samples. The three major viruses detected were
rhinoviruses, RS viruses, and enteroviruses; enteroviruses were found to be dominant in patients aged

3 years. There was no change in the levels of rhinoviruses and RS viruses between the two age groups,
defined as children aged <3 years and children aged
3 years. Serum concentrations of ECP, IL-5, and IP-
10 were significantly elevated in virus-induced acute asthma cases compared with controls. Serum ECP
values were significantly higher in patients with virus-induced asthma at age
3 years compared with
those aged <3 years. Among the 27 cytokines/chemokines, serum IP-10 was significantly higher in virusinduced
asthma in patients <3 years than in those
3 years. Serum ECP and IL-5 production correlated
significantly with age, whereas serum IP-10 showed an inverse correlation with age.
Conclusions: Age-related differences in cytokine profiles and eosinophil activation may be related to
virus-induced acute exacerbations of childhood asthma.