title: IgE antibodies to animal-derived lipocalin, kallikrein and secretoglobin are markers of bronchial inflammation in severe childhood asthma.
abstract: BACKGROUND
  Component-resolved allergy diagnostics enables the detection of crossreactive or species-specific allergen components. This study analysed Immunoglobulin E (IgE) profiles to single allergen components in relation to bronchial inflammation in severe childhood asthma.
  
  
  METHODS
  Ninety-five schoolchildren were assessed, 39 with controlled mild-to-moderate asthma and 56 uncontrolled severe asthmatics. Allergen components (n = 111) of food allergens, pollen and perennial aeroallergens were analysed using an immunosolid-phase allergen chip. Blood eosinophils (10(9) × l(-1)), bronchial inflammation (FeNO, ppb), lung function (FEV(1)%) and bronchial hyper-responsiveness (BHR) (dose-response slope of methacholine challenge) were measured.
  
  
  RESULTS
  A specific IgE response to more than three animal-derived components--lipocalin (nMus m 1, rEqu c 1, Fel d 4, rCan f 1, 2), kallikrein (rCan f 5) and secretoglobin (rFel d 1)--was more common among severe asthmatics compared to children with controlled asthma (n = 14 vs n = 3, P = 0.030). These subjects also displayed higher blood eosinophils (0.65 vs 0.39, P = 0.021), higher Fractional exhaled nitric oxide (38 ppb vs 25 ppb, P = 0.021) and increased BHR (112 vs 28, P = 0.002) compared to other severe asthmatics positive to fewer lipocalin/kallikrein/secretoglobin components. Among all sensitized subjects, there were correlations between specific IgE levels for rFel d 4 and nMus m 1 (r = 0.751, P ≤ 0.001) and for rFel d 4 and rEqu c 1 (r = 0.850, P ≤ 0.001).
  
  
  CONCLUSIONS
  Multi-sensitization towards lipocalin, kallikrein and secretoglobin components is associated with increased bronchial inflammation in severe asthmatics. In addition, crossreactive patterns were observed between different lipocalin components.
authors.affiliation: Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden. bjorn.nordlund@karolinska.se
authors.forename: B
authors.initials: B
authors.lastname: Nordlund
authors.forename: J R
authors.initials: JR
authors.lastname: Konradsen
authors.forename: I
authors.initials: I
authors.lastname: Kull
authors.forename: M P
authors.initials: MP
authors.lastname: Borres
authors.forename: A
authors.initials: A
authors.lastname: Önell
authors.forename: G
authors.initials: G
authors.lastname: Hedlin
authors.forename: H
authors.initials: H
authors.lastname: Grönlund
mesh_terms: D000293:Adolescent; D000485:Allergens / Q000276:immunology*; D000818:Animals; D001249:Asthma / Q000175:diagnosis* / Q000276:immunology*; D015415:Biomarkers; D001991:Bronchitis / Q000175:diagnosis / Q000276:immunology; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology*; D007610:Kallikreins / Q000276:immunology*; D054834:Lipocalins / Q000276:immunology*; D008297:Male; D060765:Secretoglobins / Q000276:immunology*
chemical_list: D000485:Allergens; D015415:Biomarkers; D054834:Lipocalins; D060765:Secretoglobins; D007073:Immunoglobulin E; D007610:Kallikreins