title: Cytokine profiling in exhaled breath condensate after exercise challenge in asthmatic children with post-exercise symptoms.
abstract: BACKGROUND
  Markers of exhaled breath condensate (EBC) correlate with lung function impairment, airway remodeling and different aspects of the disease such as exercise-induced bronchoconstriction (EIB). Aim of the study was to determine the cytokine profile in EBC of children with asthma after an exercise treadmill challenge in order to obtain clinically useful information about mechanisms of EIB; also, to assess correlations between cytokine concentrations in EBC and clinical characteristics of the patients.
  
  
  METHODS
  The study population consisted of 25 randomly selected children, aged 8 to 19 years, with asthma and EIB symptoms despite the use of control medications. Patients on the day of the study visit underwent fractional exhaled nitric oxide measurement (FeNO) and baseline spirometry, performed an exercise treadmill challenge (ETC), and EBC samples were obtained at the end of the ETC.
  
  
  RESULTS
  In asthmatic children with positive ETC, monocyte hemotactic protein-1 (MCP-1) and IL-16 adjusted to pre-EBC forced expiratory volume in 1 s (FEV1) were significantly higher compared to children with negative ETC (p = 0.022 and p = 0.017 respectively). After adjustment to pre-EBC FEV1 other cytokines (IL-4, IL-5, IL-6, IL-8, MIG, TNF-α) were not related to post-exercise changes in FEV1.
  
  
  CONCLUSIONS
  We observed a specific inflammatory profile in the airways of asthmatic children with bronchoconstriction induced by exercise. The concentration of cytokines in EBC depended on the post-exercise decrease in FEV1, which was measured by the area under the curve (AUC). MCP-1 and IL-16, adjusted to pre-EBC FEV1, were significantly higher in children with a positive exercise challenge compared to those with a negative one.
authors.affiliation: Department of Internal Medicine, Asthma and Allergy, Barlicki University Hospital, Medical University of Lodz, Lodz, Poland.
authors.forename: Paweł
authors.initials: P
authors.lastname: Majak
authors.affiliation: Department of Paediatrics and Allergy, Medical University of Lodz, Lodz, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Jerzyńska
authors.affiliation: Department of Paediatrics and Allergy, Medical University of Lodz, Lodz, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Bojo
authors.affiliation: Department of Paediatrics and Allergy, Medical University of Lodz, Lodz, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Brzozowska
authors.affiliation: Department of Biology and Genetics, Medical University of Gdansk, Gdansk, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Koczkowska
authors.affiliation: Faculty of Mathematics and Computer Science, University of Lodz, Lodz, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Sielski
authors.affiliation: Department of Social and Preventive Medicine, Medical University of Lodz, Lodz, Poland.
authors.forename: Włodzimierz
authors.initials: W
authors.lastname: Stelmach
authors.affiliation: Institute of Dental Surgery, Faculty of Medicine and Dentistry, Medical University of Lodz, Lodz, Poland.
authors.forename: Rafał
authors.initials: R
authors.lastname: Stelmach
authors.affiliation: Institute of Dental Surgery, Faculty of Medicine and Dentistry, Medical University of Lodz, Lodz, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Janas
authors.affiliation: Department of Paediatrics and Allergy, Medical University of Lodz, Lodz, Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Stelmach
keywords: asthma; children; cytokines; exercise-induced bronchoconstriction; exhaled breath condensate