title: Adult serum cytokine concentrations and the persistence of asthma.
abstract: BACKGROUND
  Cytokines play a pivotal role in regulating the development and persistence of the inflammatory process in asthma. Our aim was to investigate whether asthma persistence or remission is associated with a specific cytokine profile.
  
  
  METHODS
  The Tasmanian Longitudinal Health Study followed participants from 7 to 44 years of age. Serum concentrations of interleukin (IL)-4, IL-5, IL-6, IL-8, IL-10 and tumor necrosis factor-alpha (TNF-α) were measured at age 44 years. Participants were categorized into five phenotypes (early-onset noncurrent asthma, early-onset current asthma, late-onset noncurrent asthma and late-onset current asthma). Those who had never had asthma formed the reference group. Multivariable linear regression was used to compare serum cytokine concentrations between each phenotype and the reference group.
  
  
  RESULTS
  IL-10 concentrations were significantly lower in serum from the early-onset current asthma group than in the reference group (ratio of geometric means 0.58; 95% confidence interval 0.33-0.99; p = 0.048). IL-6 concentrations for the late-onset remitted group were also significantly lower than in the reference group (p = 0.009). The TNF-α concentrations were significantly lower for both early-and late-onset remitted asthma phenotypes when compared with the reference group. No associations were detected between serum concentrations of IL-4, IL-5 or IL-8 and these specific longitudinal asthma phenotypes.
  
  
  CONCLUSIONS
  Our findings suggest a possible role for deficient IL-10 responses in the persistence of early-onset asthma. Lower IL-6 and TNF-α concentrations in serum from those with remitted asthma suggest that these proinflammatory cytokines may be actively suppressed during asthma remission.
authors.affiliation: Centre for MEGA Epidemiology, Melbourne School of Population Health, The University of Melbourne, Melbourne, Vic., Australia.
authors.forename: R K
authors.initials: RK
authors.lastname: Kandane-Rathnayake
authors.forename: M L K
authors.initials: ML
authors.lastname: Tang
authors.forename: J A
authors.initials: JA
authors.lastname: Simpson
authors.forename: J A
authors.initials: JA
authors.lastname: Burgess
authors.forename: D
authors.initials: D
authors.lastname: Mészáros
authors.forename: I
authors.initials: I
authors.lastname: Feather
authors.forename: M C
authors.initials: MC
authors.lastname: Southey
authors.forename: C J
authors.initials: CJ
authors.lastname: Schroen
authors.forename: J
authors.initials: J
authors.lastname: Hopper
authors.forename: S C
authors.initials: SC
authors.lastname: Morrison
authors.forename: G G
authors.initials: GG
authors.lastname: Giles
authors.forename: E H
authors.initials: EH
authors.lastname: Walters
authors.forename: S C
authors.initials: SC
authors.lastname: Dharmage
authors.forename: M C
authors.initials: MC
authors.lastname: Matheson
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D001249:Asthma / Q000453:epidemiology* / Q000276:immunology*; D002648:Child; D016207:Cytokines / Q000097:blood*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood*; D008297:Male; D012075:Remission, Spontaneous; D013648:Tasmania / Q000453:epidemiology; D055815:Young Adult
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators