title: Exhaled breath condensate levels of eotaxin and macrophage-derived chemokine in stable adult asthma patients.
abstract: BACKGROUND
  Asthma is associated with esoinophilic airway inflammation and overproduction of T-helper type 2 (Th2) lymphocyte-related cytokines.
  
  
  OBJECTIVE
  This study assessed the eosinophil chemoattractant eotaxin and Th2-specific macrophage-derived chemokine (MDC) in the adult asthmatic airway. Eotaxin and MDC levels were determined in exhaled breath condensate (EBC) obtained from adult patients with asthma.
  
  
  METHODS
  Fifty-four asthmatics (20 male, mean (SD) age 40 (12) years and percentage predicted forced expiratory volume in 1 s (FEV(1)) 81.7 (20.8)) and 20 age- and sex-matched controls were studied. EBC was collected using EcoScreen by 10 min of tidal breathing with a nose clip. Concentrations of eotaxin and MDC were measured by ELISA.
  
  
  RESULTS
  Asthma patients on inhaled corticosteroid (ICS) had a higher median interquartile range (IQR) level of eotaxin than the steroid-naïve asthmatics (18.5 (17.7-20.1) vs. 17.9 (17.0-18.6) pg/mL, P=0.02) and controls (18.5 (17.7-20.1) pg/mL vs 17.4 (16.3-18.0) pg/mL, P=0.001). Eotaxin level in EBC had a significant negative correlation with the FEV(1)/forced vital capacity ratio (r=-0.43, P=0.03) in steroid-naïve asthmatics. EBC MDC level was higher in subjects on ICS than the steroid naïve asthmatics (120 (118-125) vs. 117 (116-119) pg/mL, P=0.01) and the controls (120 (118-125) vs. 117 (116-120) pg/mL, P=0.02).
  
  
  CONCLUSIONS
  Eotaxin and MDC could be measured in EBC of adults with asthma. EBC eotaxin and MDC levels were higher in asthmatics on ICS than the steroid-naïve asthmatics or controls. Exhaled chemokines may be potential non-invasive markers for assessing airway inflammation in asthmatics.
authors.affiliation: Departments of Medicine and Therapeutics, Paediatrics and Chemical Pathology, The Chinese University of Hong Kong, Hong Kong, China. fannyko@cuhk.edu.hk
authors.forename: F W S
authors.initials: FW
authors.lastname: Ko
authors.forename: C Y K
authors.initials: CY
authors.lastname: Lau
authors.forename: T F
authors.initials: TF
authors.lastname: Leung
authors.forename: G W K
authors.initials: GW
authors.lastname: Wong
authors.forename: C W K
authors.initials: CW
authors.lastname: Lam
authors.forename: C K W
authors.initials: CK
authors.lastname: Lai
authors.forename: D S C
authors.initials: DS
authors.lastname: Hui
mesh_terms: D000280:Administration, Inhalation; D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000328:Adult; D001249:Asthma / Q000188:drug therapy / Q000276:immunology*; D015415:Biomarkers / Q000032:analysis; D001944:Breath Tests; D016022:Case-Control Studies; D054413:Chemokine CCL11; D054422:Chemokine CCL22; D019742:Chemokines, CC / Q000032:analysis*; D003430:Cross-Sectional Studies; D004804:Eosinophils / Q000276:immunology; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008168:Lung / Q000276:immunology*; D008297:Male; D012882:Skin Tests; D018709:Statistics, Nonparametric
chemical_list: D000305:Adrenal Cortex Hormones; D015415:Biomarkers; C515456:CCL11 protein, human; C515482:CCL22 protein, human; D054413:Chemokine CCL11; D054422:Chemokine CCL22; D019742:Chemokines, CC