title: Cytokine responses in primary and secondary respiratory syncytial virus infections.
abstract: Primary respiratory syncytial virus (RSV) infections are characterized by high levels of IL-8 and an intense neutrophilia. Little is known about the cytokine responses in secondary infections. Preschool children experiencing RSV secondary infections were recruited from the siblings of infants admitted to hospital with RSV acute bronchiolitis.
  
  
  
  Fifty-one infants with acute bronchiolitis (39 RSV positive, 12 RSV negative) and 20 age-matched control infants were recruited. In addition, seven older siblings of infants from the RSV-positive cohort and confirmed RSV infection were recruited. Samples of nasal secretions were obtained using a flocked swab, and secretions extracted using centrifugation. Cytokine bead array was used to obtain levels of interleukin (IL)-17A, IL-8, IL-6, IL-21, and tumor necrosis factor-α.
  
  
  
  Levels of IL-8 and IL-6 were significantly lower in the RSV-positive siblings compared with the RSV-positive infants. There were no significant differences between levels of the other cytokines in the primary and secondary infections.
  
  
  
  The very high levels of IL-8 and IL-6 response characteristic of the primary RSV infection was not observed in secondary RSV-positive infections and this did not appear to be due to a global reduction in cytokine production.
authors.affiliation: Department of Respiratory Medicine, Sheffield Children's Hospital, Sheffield, UK.
authors.forename: Kelechi
authors.initials: K
authors.lastname: Ugonna
authors.affiliation: Third Department of Paediatrics, Attikon Hospital, University of Athens School of Medicine, Athens, Greece.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Douros
authors.affiliation: Department of Infection and Immunity, University of Sheffield, Sheffield, UK.
authors.forename: Colin D
authors.initials: CD
authors.lastname: Bingle
authors.affiliation: School of Paediatrics and Child Health, University of Western Australia, Princess Margaret Hospital, Subiaco, Western Australia, Australia.
authors.forename: Mark L
authors.initials: ML
authors.lastname: Everard
mesh_terms: D001988:Bronchiolitis / Q000276:immunology* / Q000821:virology*; D016022:Case-Control Studies; D015331:Cohort Studies; D016207:Cytokines / Q000276:immunology*; D058872:Epidemics; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D015850:Interleukin-6 / Q000276:immunology; D016209:Interleukin-8 / Q000276:immunology; D008297:Male; D009504:Neutrophils / Q000276:immunology; D010343:Patient Admission; D018357:Respiratory Syncytial Virus Infections / Q000276:immunology*; D012136:Respiratory Syncytial Viruses; D012621:Seasons; D035781:Siblings
chemical_list: C508606:CXCL8 protein, human; D016207:Cytokines; C508600:IL6 protein, human; D015850:Interleukin-6; D016209:Interleukin-8