title: Molecular characterization of wheat allergens specifically recognized by patients suffering from wheat-induced respiratory allergy.
abstract: BACKGROUND
  Wheat (Triticum aestivum) is an important allergen source responsible for various clinical manifestations of allergy (i.e. food allergy, pollen allergy, respiratory allergy to flour-Baker's asthma).
  
  
  OBJECTIVE
  The objective of this study was the molecular and immunological characterization of new recombinant wheat allergens and to evaluate their usefulness for the diagnosis of allergy to wheat.
  
  
  METHODS
  A T. aestivum cDNA library was constructed and screened with serum IgE from patients suffering from wheat allergy to identify cDNAs coding for new wheat allergens. The allergen-encoding cDNAs were expressed in Escherichia coli and purified to homogeneity. IgE reactivity of recombinant proteins was analysed in RAST-based, non-denaturing dot blot experiments and by ELISA with sera from wheat allergic patients and their allergenic activity was assessed in basophil degranulation experiments.
  
  
  RESULTS
  We report the molecular characterization, recombinant expression and purification of five wheat allergens, a thioredoxin h isoform, glutathione transferase, 1-Cys-peroxiredoxin, profilin and dehydrin. Homologous proteins were identified by sequence comparisons in various plants. 1-Cys-peroxiredoxin appeared to be the most relevant of the newly identified wheat allergens according to prevalence of IgE recognition and results from basophil degranulation experiments. It showed IgE cross-reactivity with seed proteins from barley, rye, rice, maize, soy, oat and spelt. 1-Cys-peroxiredoxin, glutathione transferase and dehydrin were mainly recognized by patients with baker's asthma but not wheat-induced food allergy.
  
  
  CONCLUSIONS
  The characterized recombinant wheat allergens may be useful for the development of serological tests which allow the discrimination of different clinical manifestations of wheat allergy.
authors.affiliation: Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna General Hospital, Waehringer Guertel 18-20, Vienna, Austria.
authors.forename: S
authors.initials: S
authors.lastname: Pahr
authors.forename: C
authors.initials: C
authors.lastname: Constantin
authors.forename: A
authors.initials: A
authors.lastname: Mari
authors.forename: S
authors.initials: S
authors.lastname: Scheiblhofer
authors.forename: J
authors.initials: J
authors.lastname: Thalhamer
authors.forename: C
authors.initials: C
authors.lastname: Ebner
authors.forename: S
authors.initials: S
authors.lastname: Vrtala
authors.forename: I
authors.initials: I
authors.lastname: Mittermann
authors.forename: R
authors.initials: R
authors.lastname: Valenta
mesh_terms: D000328:Adult; D000485:Allergens / Q000737:chemistry* / Q000276:immunology / Q000302:isolation & purification*; D000595:Amino Acid Sequence; D001249:Asthma / Q000276:immunology; D015550:Cell Degranulation / Q000276:immunology; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D015151:Immunoblotting; D007073:Immunoglobulin E; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry* / Q000276:immunology / Q000302:isolation & purification*; D011994:Recombinant Proteins / Q000737:chemistry / Q000276:immunology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D021182:Wheat Hypersensitivity / Q000276:immunology*; D055815:Young Adult
chemical_list: D000485:Allergens; D010940:Plant Proteins; D011994:Recombinant Proteins; D007073:Immunoglobulin E