title: Elevated metal concentrations in the CF airway correlate with cellular injury and disease severity.
abstract: BACKGROUND
  Bio-active trace metals have been identified in respiratory tract secretions of subjects with lung disease and may potentially influence bacterial virulence, inflammation and disease severity. We measured a diverse range of metal ions in sputum samples from subjects with CF and non-CF bronchiectasis (NCFB) compared to healthy controls and examined their relationship to airway inflammation, disease severity and the presence of bacterial pathogens.
  
  
  METHODS
  We studied 45 subjects with CF, 8 with NCFB and 8 healthy controls. Metal concentrations were measured in sputum supernatant by inductively-coupled plasma mass spectrometry and correlated with sputum inflammatory cell counts, lactate dehydrogenase (LDH) and interleukin (IL)-8 concentrations, atmospheric particulate matter, lung function, clinical status and participant demographics.
  
  
  RESULTS
  Sputum from subjects with CF and NCFB contained increased concentrations of magnesium, calcium, iron and zinc. Metal ion concentrations correlated positively with LDH levels. The concentrations of magnesium, iron and zinc positively correlated with IL-8. A sub-group of CF subjects with severe lung disease demonstrated increased sputum molybdenum concentrations.
  
  
  CONCLUSIONS
  Elevated concentrations of sputum metal ions appear to be associated with cell/tissue necrosis and inflammation in subjects with CF and NCFB. Sputum molybdenum concentrations may be a biomarker of severe CF airway disease.
authors.affiliation: Department of Thoracic Medicine, The Prince Charles Hospital, Rode Road, Chermside, Brisbane, Queensland 4032, Australia; School of Medicine, University of Queensland, 288 Herston Road, Herston, Brisbane, Queensland 4029, Australia; The Iron Metabolism Laboratory, Queensland Institute of Medical Research, 300 Herston Road, Herston, Queensland 4029, Australia. Electronic address: Daniel_j_smith@health.qld.gov.au.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Smith
authors.affiliation: School of Medicine, University of Queensland, 288 Herston Road, Herston, Brisbane, Queensland 4029, Australia; The Iron Metabolism Laboratory, Queensland Institute of Medical Research, 300 Herston Road, Herston, Queensland 4029, Australia.
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Anderson
authors.affiliation: Department of Thoracic Medicine, The Prince Charles Hospital, Rode Road, Chermside, Brisbane, Queensland 4032, Australia; School of Medicine, University of Queensland, 288 Herston Road, Herston, Brisbane, Queensland 4029, Australia; Queensland Children's Medical Research Institute, Royal Children's Hospital, Herston Road, Herston, Queensland 4029, Australia.
authors.forename: Scott C
authors.initials: SC
authors.lastname: Bell
authors.affiliation: Department of Thoracic Medicine, The Prince Charles Hospital, Rode Road, Chermside, Brisbane, Queensland 4032, Australia; School of Medicine, University of Queensland, 288 Herston Road, Herston, Brisbane, Queensland 4029, Australia; The Iron Metabolism Laboratory, Queensland Institute of Medical Research, 300 Herston Road, Herston, Queensland 4029, Australia.
authors.forename: David W
authors.initials: DW
authors.lastname: Reid
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D003430:Cross-Sectional Studies; D003550:Cystic Fibrosis / Q000175:diagnosis / Q000378:metabolism*; D005260:Female; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism; D007501:Iron / Q000378:metabolism*; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008274:Magnesium / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D008982:Molybdenum / Q000378:metabolism*; D012129:Respiratory Function Tests; D012720:Severity of Illness Index; D013183:Sputum / Q000378:metabolism; D055815:Young Adult; D015032:Zinc / Q000378:metabolism*
chemical_list: D015415:Biomarkers; C508606:CXCL8 protein, human; D016209:Interleukin-8; D008982:Molybdenum; D007501:Iron; D007770:L-Lactate Dehydrogenase; D008274:Magnesium; D015032:Zinc
keywords: Bio-metals; Cellular injury; Cystic Fibrosis; Inflammation