Detection of IL-6, IL-8. IL-10, and rantes in the nasopharyngeal and tracheal aspirates of children with respiratory syncytial virus (RSV) Disease

Introduction RSV is the most common cause of tower respiratory tract disease in infants. The pathogènes of RSV disease, and specifically the role of inflammatory mediators, is not well understood. Because cytokines are believed to be important in the recruitment of white blood cells (WBCs), we sought lo determine the concentration of cytokines in nasopharyngeal (NP) and trachéal aspirate (TA) of children with RSV disease. Methods: During the 1996-1997 season, we prospectively studied 14 imubated and 14 non-intubated children (median age: 1.5 months; sex: 15 males, 13 females) admitted to Children's Medical Center, Dallas with RSV broadùolitis/pneumonia. NP and TA samples were obtained from inlubated patients on hospital days I, 3. and 5. NP samples were obtained from non-intnbated patients on hospital days 1 and 3. All samples were analyzed for 1) IL-6, O.-8, IL-10, and RANTES concentrations (ELISA); 2) WBC and PMN counts; and 3) quantitative RSV cultures. Comparisons were determined using the Spearman Rank Order Correlation and differences betweoi intubated and non-intubated patients were determined using the Mann-Whitney Rank Sum Test ResBhs We found that IL-6 (range 177-9617 pg/ml), IL-8 (501-2087 pg/ml). IL-10 (1-529 pg/ml), and RANTES (3-1426 pg/ml) were present in the NP and TA of ail patients evaluated. In NP samples, WBC and PMN counts significantly correlated with IL-6, IL-10, and RANTES concentrations. In TA samples, the WBC and PMN counts correlated significantly with IL-6 and IL-10 concentrations. RSV titers in NP correlated significantly with NP WBC counts and with concentrations of IL-6, IL-10, aad RANTES. And finally, NP RANTES concentrations were significantly greater in non-intubated patients compared to intubated patients. CoadMMM: IL-6, IL-8, IL-10, and RANTES are present in the NP and TA of patients with RSV disease and, therefore, may play a role in the inflammatory response induced by RSV infection. This would have implications for future therapeutic strategies aimed at inununomodulation of RSV disease.