RT Journal Article SR Electronic T1 IL-8 and neutrophil elastase levels in the respiratory tract of infants with RSV bronchiolitis JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 139 OP 143 DO 10.1034/j.1399-3003.1999.14a23.x VO 14 IS 1 A1 M Abu-Harb A1 F Bell A1 A Finn A1 WH Rao A1 L Nixon A1 D Shale A1 ML Everard YR 1999 UL http://erj.ersjournals.com/content/14/1/139.abstract AB The aim of this study was to determine whether interleukin (IL)-8 is released within the upper respiratory tract of infants during respiratory syncytial virus (RSV) bronchiolitis and whether the large number of polymorphonuclear neutrophils (PMNs) present in the respiratory tract of these infants are contributing to the inflammation through release of inflammatory mediators. Twenty-seven infants with acute bronchiolitis were recruited during one winter epidemic and 20 infant control subjects were recruited from a cohort participating in a community-based vaccine study. Samples of airways fluid were obtained using nasal lavage. The lavage fluid was spun to remove the cells, and the supernatant was stored at -70 degrees C. The supernatants were subsequently assayed for the presence of IL-8, total human neutrophil elastase (HNE) and neutrophil elastase activity. In the children with bronchiolitis compared with control infants, elevated levels of IL-8 (median (range) 1.53 (0-153) versus 0 (0-5.6) ng x mL(-1)) HNE (136 (32-694) versus 14 (0-516) ng x mL(-1)) and elastase activity (4 (1-220) versus 1 (0-339) mU x mL(-1)) were found. These results indicate that interleukin-8 is released in the upper respiratory tract in response to respiratory syncytial virus infection and suggest that polymorphonuclear neutrophil products are playing an important role in the inflammatory response to respiratory syncytial virus infection in infants with acute bronchiolitis. This contrasts with the predominantly eosinophilic response evident in atopic upper and lower respiratory tract disease.