title: Soluble receptor for advanced glycation end products (sRAGE) is present at high concentrations in the lungs of children and varies with age and the pattern of lung inflammation.
abstract: OBJECTIVE
  The soluble receptor for advanced glycation end products (sRAGE) plays an important role in inflammation. Few studies have looked at sRAGE levels in human lungs, and there is no information in children. Therefore, this study aimed to compare bronchoalveolar lavage fluid (BALF) and plasma sRAGE concentrations in children in relation to age and inflammation.
  
  
  METHODS
  BAL was performed in 76 children, and BALF and plasma sRAGE levels were determined by enzyme-linked immunosorbent assay.
  
  
  RESULTS
  sRAGE levels were fourfold higher in BALF than in plasma (P < 0.001). BALF sRAGE was inversely proportional to age (r = -0.333, P = 0.008) and serum immunoglobulin A (r = -0.283, P = 0.028). Plasma sRAGE showed a positive correlation to the percentage of BAL macrophages and negative correlation to the percentage of neutrophils and lymphocytes (P < 0.05). Multivariate linear regression analysis identified that the percentage of BAL lymphocytes and neutrophils were significant independent predictors of plasma sRAGE levels, while age and the percentage of BAL macrophages independently predicted BALF sRAGE levels.
  
  
  CONCLUSIONS
  In children, sRAGE is present at higher concentrations in the lung compared with blood. It appears that sRAGE varies with age, and hence future studies of sRAGE in paediatric lung disease require age matching. The significant relationship between sRAGE and lung inflammation warrants further research.
authors.affiliation: School of Medicine, The University of Queensland Queensland Centre for Pulmonary Transplantation and Vascular Disease, The Prince Charles Hospital, Brisbane, Queensland, Australia.
authors.forename: Stephanie T
authors.initials: ST
authors.lastname: Yerkovich
authors.forename: Anne B
authors.initials: AB
authors.lastname: Chang
authors.forename: Melanie L
authors.initials: ML
authors.lastname: Carroll
authors.forename: Helen L
authors.initials: HL
authors.lastname: Petsky
authors.forename: Greta
authors.initials: G
authors.lastname: Scrivener
authors.forename: John W
authors.initials: JW
authors.lastname: Upham
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging / Q000378:metabolism*; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D001999:Bronchoscopy; D002648:Child; D005260:Female; D006801:Humans; D056724:Immunity, Humoral / Q000502:physiology; D007070:Immunoglobulin A / Q000097:blood; D008168:Lung / Q000378:metabolism*; D008297:Male; D015999:Multivariate Analysis; D011014:Pneumonia / Q000378:metabolism*; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic / Q000032:analysis / Q000378:metabolism*; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D007070:Immunoglobulin A; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic