title: Relationship between sputum clusterin levels and childhood asthma.
abstract: Clusterin is a sensitive cellular biosensor of oxidative stress and has been studied as a biomarker for inflammation-associated diseases. Clusterin levels in childhood asthma have not been evaluated.
  
  
  
  (1) To evaluate sputum clusterin levels in children with asthma compared to a control group. (2) To assess the relationships between sputum clusterin levels and airway inflammation, pulmonary function, and bronchial hyperresponsiveness.
  
  
  
  This study included 170 children aged 5-18 years with stable asthma (n = 91), asthma exacerbation (n = 29), or no asthma (healthy controls; n = 50). Induced sputum, pulmonary function, and methacholine challenge tests were performed. Stable asthma was classified into two groups according to the severity. Clusterin levels in sputum were measured using an enzyme-linked immunosorbent assay.
  
  
  
  Children with stable asthma had a higher clusterin level than healthy controls [4540 (3872-5651) pg/mL vs. 3857 (1054-4369) pg/mL, P < 0.001]. The clusterin level was also more elevated in eosinophil-dominant sputum than in non-eosinophilic sputum in stable asthma [5094 (4243-6257) pg/mL vs. 4110 (1871-4839) pg/mL, P = 0.0017]. Clusterin levels were associated with asthma severity. Paradoxically, clusterin levels were lower during asthma exacerbation than in stable asthma [1838 (350-4790] pg/mL vs. 4540 (3872-5651) pg/mL, P < 0.001]. Clusterin levels were strongly correlated with the methacholine concentration that caused a 20% decrease in the forced expiratory volume in 1 s (r = -0.617, P < 0.001); there was no significant correlation between clusterin levels and other pulmonary function parameters.
  
  
  
  Clusterin levels were altered in children with stable asthma and asthma exacerbation because of its antioxidant and anti-inflammatory effects. Clusterin may be a marker that reflects airway inflammation and severity of symptoms, and it can be used in the assessment and management of childhood asthma.
authors.affiliation: Department of Pediatrics, Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: I S
authors.initials: IS
authors.lastname: Sol
authors.affiliation: Department of Pediatrics, Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Y H
authors.initials: YH
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Y A
authors.initials: YA
authors.lastname: Park
authors.affiliation: Department of Pediatrics, Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: K E
authors.initials: KE
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: J Y
authors.initials: JY
authors.lastname: Hong
authors.affiliation: Department of Pediatrics, Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: M N
authors.initials: MN
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Y S
authors.initials: YS
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: M S
authors.initials: MS
authors.lastname: Oh
authors.affiliation: Department of Pediatrics, Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: S H
authors.initials: SH
authors.lastname: Yoon
authors.affiliation: Department of Pediatrics, Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: M J
authors.initials: MJ
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: K W
authors.initials: KW
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: M H
authors.initials: MH
authors.lastname: Sohn
authors.affiliation: Department of Pediatrics, Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: K E
authors.initials: KE
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000175:diagnosis / Q000276:immunology* / Q000378:metabolism*; D015415:Biomarkers; D001985:Bronchial Provocation Tests; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D051152:Clusterin / Q000378:metabolism*; D018450:Disease Progression; D004804:Eosinophils; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D013147:Spirometry; D013183:Sputum / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D051152:Clusterin
keywords: airway inflammation; asthma exacerbation; clusterin; stable asthma