IL-5 and IFN-gamma Levels in Nasopharyngeal Secretions from Non-Asthmatic Wheezing Children with Respiratory Syncytial Virus, Influenza A Virus Infection and Asthmatic Children / 소아알레르기및호흡기학회지

ABSTRACT

BACKGROUND: Infection with respiratory virus has been shown to exacerbate asthma. However, the role of a respiratory virus in the pathogenesis of chronic asthma and/or wheezing in young children has not been clearly defined. And it also has been debated whether virus-induced wheezing in young children is an entity different from allergic asthma, or just a different expression of the same disease. In this study, we attempted to evaluate the importance of eosinophilic inflammation, comparing IL-5 and IFN-gamma levels in nasopharyngeal secretions in wheezing children with or without viral infection and the controls. METHODS: We compared IL-5 and IFN-gamma levels in nasopharyngeal secretions from 38 non-asthmatic wheezing children with viral infections (RSV in 21 children, influenza A virus in 17 children), 12 asthmatic children without viral infections and 16 children as the controls. RESULTS: The present study reported that RSV infection in children induced more releasing of IL-5 in nasopharyngeal secretions than the influenza A virus infected ones and the controls. On the other hand, the releasing of IFN-gamma levels in nasopharyngeal secretions from children with influenza A virus infection was significantly higher than those of the children with RSV infection or asthmatic children. CONCLUSION: RSV infection in children may play a role in the immune response toward a Th2 phenotype as increasing IL-5 secretion in nasopharyngeal secretion. Increased IFN-gamma production in response to the influenza A virus infection may be related to the effective Th1 responses.