title: The high molecular weight glutenin subunit Bx7 allergen from wheat contains repetitive IgE epitopes.
abstract: BACKGROUND
  Wheat is one of the most common food allergen sources for children and adults. The aim of this study was to characterize new wheat allergens using an IgE discovery approach and to investigate their IgE epitopes.
  
  
  METHODS
  A cDNA expression library representing the wheat transcriptome was constructed in phage lambda gt11 and screened with IgE antibodies from wheat food allergic patients. IgE-reactive cDNA clones coding for portions of high molecular weight (HMW) glutenin subunits were identified by sequence analysis of positive clones. IgE epitopes were characterized using recombinant fragments from the HMW Bx7 and synthetic peptides thereof for testing of allergic patients' sera and in basophil degranulation assays.
  
  
  RESULTS
  We found that the major IgE-reactive areas of HMW glutenins are located in the repetitive regions of the protein and could show that two independent IgE-reactive fragments from HMW Bx7 contained repetitive IgE epitopes.
  
  
  CONCLUSIONS
  Our results demonstrate that IgE antibodies from wheat food allergic patients can recognize repetitive epitopes in one of the important wheat food allergens. Recombinant HMW Bx7 may be included into the panel of allergens for component-resolved diagnosis of wheat food allergy.
authors.affiliation: Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology & Immunology, Vienna General Hospital, Medical University of Vienna, Vienna, Austria; Christian Doppler Laboratory for the Development of Allergen Chips, Medical University of Vienna, Vienna, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Baar
authors.forename: S
authors.initials: S
authors.lastname: Pahr
authors.forename: C
authors.initials: C
authors.lastname: Constantin
authors.forename: S
authors.initials: S
authors.lastname: Giavi
authors.forename: N G
authors.initials: NG
authors.lastname: Papadopoulos
authors.forename: A S
authors.initials: AS
authors.lastname: Pelkonen
authors.forename: M J
authors.initials: MJ
authors.lastname: Mäkelä
authors.forename: S
authors.initials: S
authors.lastname: Scheiblhofer
authors.forename: J
authors.initials: J
authors.lastname: Thalhamer
authors.forename: M
authors.initials: M
authors.lastname: Weber
authors.forename: C
authors.initials: C
authors.lastname: Ebner
authors.forename: A
authors.initials: A
authors.lastname: Mari
authors.forename: S
authors.initials: S
authors.lastname: Vrtala
authors.forename: R
authors.initials: R
authors.lastname: Valenta
mesh_terms: D000485:Allergens / Q000276:immunology*; D000595:Amino Acid Sequence; D015549:Basophil Degranulation Test; D004797:Enzyme-Linked Immunosorbent Assay; D018985:Epitopes, B-Lymphocyte / Q000276:immunology*; D005983:Glutens / Q000737:chemistry* / Q000276:immunology*; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000276:immunology; D021182:Wheat Hypersensitivity / Q000276:immunology*
chemical_list: D000485:Allergens; D018985:Epitopes, B-Lymphocyte; D011994:Recombinant Proteins; D007073:Immunoglobulin E; D005983:Glutens; C037302:glutenin
keywords: allergy; component-resolved diagnosis; recombinant wheat allergens; repetitive IgE epitope; wheat food allergy