title: IgE binding to peanut components by four different techniques: Ara h 2 is the most relevant in peanut allergic children and adults.
abstract: BACKGROUND
  Several studies have analysed the diagnostic value of specific IgE (sIgE) for individual peanut allergens. However, little is known about the concordance between different techniques available in both children and adults.
  
  
  OBJECTIVE
  To evaluate the value of individual peanut allergens by different techniques, i.e. multi-plexed microarray, single-plexed IgE assay, skin prick test (SPT) and immunoblot in both peanut allergic adults and children.
  
  
  METHODS
  Sensitization patterns to peanut allergens Ara h 1, 2, 3, and 8 were evaluated using four different techniques: multi-plexed microarray immunoassay, single-plexed IgE assay, SPT and immunoblot. Twenty-two peanut allergic adults and 15 children scored on clinical severity according to double-blind, placebo-controlled food challenges and 27 atopic control patients were included.
  
  
  RESULTS
  Comparable sensitivity values were found between all four techniques in adults, with the highest sensitivity for Ara h 2 (76.2-95.5%, compared to 100% with all techniques in children). The multi-plexed assay to Ara h 1 (93.3%) demonstrated a higher sensitivity compared with the other three techniques (P = 0.04) in children, but absolute values were perfectly correlated. There were no differences between adults and children. The area under the receiver operating characteristic curve (AUC) of sIgE to Ara h 1 was higher with the multi-plexed assay compared with the single-plexed assay (0.91 vs. 0.75). In adults, sIgE to Ara h 1, 2, and 3 was correlated with clinical severity. No such correlation was found in children.
  
  
  CONCLUSIONS
  In conclusion, the single- and multi-plexed assay, SPT and immunoblot perform equally in both peanut allergic adults and children, with Ara h 2 being most often recognized with all techniques. Specific IgE to Ara h 1, 2, and 3 in adults was correlated with severity.
authors.affiliation: Department of Dermatology/Allergology, University Medical Center Utrecht, Utrecht, The Netherlands. r.j.b.klemans-3@umcutrecht.nl
authors.forename: R J B
authors.initials: RJ
authors.lastname: Klemans
authors.forename: X
authors.initials: X
authors.lastname: Liu
authors.forename: A C
authors.initials: AC
authors.lastname: Knulst
authors.forename: M J
authors.initials: MJ
authors.lastname: Knol
authors.forename: F
authors.initials: F
authors.lastname: Gmelig-Meyling
authors.forename: E
authors.initials: E
authors.lastname: Borst
authors.forename: S G M A
authors.initials: SG
authors.lastname: Pasmans
authors.forename: E F
authors.initials: EF
authors.lastname: Knol
mesh_terms: D055516:2S Albumins, Plant / Q000276:immunology; D000328:Adult; D000367:Age Factors; D052179:Antigens, Plant / Q000276:immunology*; D010367:Arachis / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006023:Glycoproteins / Q000276:immunology; D006801:Humans; D007108:Immune Tolerance; D007118:Immunoassay / Q000379:methods; D007073:Immunoglobulin E / Q000276:immunology*; D008297:Male; D008565:Membrane Proteins; D021183:Peanut Hypersensitivity / Q000175:diagnosis* / Q000276:immunology*; D010940:Plant Proteins / Q000276:immunology; D055314:Seed Storage Proteins / Q000276:immunology; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
chemical_list: D055516:2S Albumins, Plant; D052179:Antigens, Plant; C500889:Ara h 1 protein, Arachis hypogaea; C500890:Ara h 2 allergen, Arachis hypogaea; D006023:Glycoproteins; D008565:Membrane Proteins; D010940:Plant Proteins; D055314:Seed Storage Proteins; C118207:allergen Ara h3; D007073:Immunoglobulin E
keywords: immunoblot; multi-plexed microarray immunoassay; peanut allergy; single-plexed IgE assay; skin prick test