title: Allergologic exploration of germins and germin-like proteins, a new class of plant allergens.
abstract: BACKGROUND
  Germins and the related germin-like proteins (GLPs) are glycoproteins expressed in many plants in response to biotic and abiotic stress. To test the potential impact of germins and GLPs, recombinant germin from Triticum aestivum (tGermin) and GLPs from Arabidopsis thaliana (tGLP), both produced in transformed tobacco plants, were used.
  
  
  METHODS
  Sera from 82 patients with type I allergy to birch, grass or mugwort pollen and/or wheat were tested in immunoblot for IgE binding to tGermin and tGLP, and the IgE reactivity after chemical and enzymatic deglycosylation was analysed. The biological activity of tGermin and tGLP was determined in a histamine release assay and in skin prick testing (SPT).
  
  
  RESULTS
  In an immunoblotting assay, 24 out of 82 tested sera (29.26%) from allergic patients showed IgE-binding to tGermin, and 18 of these sera (21.95%) displayed also IgE-binding to tGLP. The deglycosylation experiments indicated that glycan moieties contribute significantly to the IgE-binding of tGermin and tGLP. Both tGermins and tGLP induced specifically histamine release in an in vitro assay as well as in SPT.
  
  
  CONCLUSIONS
  Our in vitro and in vivo findings demonstrate that germin and GLPs are capable to bind IgE most likely via carbohydrate determinants, and represent allergenic molecules.
authors.affiliation: Department of Pathophysiology, Vienna Medical School, Austria.
authors.forename: E
authors.initials: E
authors.lastname: Jensen-Jarolim
authors.forename: B
authors.initials: B
authors.lastname: Schmid
authors.forename: F
authors.initials: F
authors.lastname: Bernier
authors.forename: A
authors.initials: A
authors.lastname: Berna
authors.forename: T
authors.initials: T
authors.lastname: Kinaciyan
authors.forename: M
authors.initials: M
authors.lastname: Focke
authors.forename: C
authors.initials: C
authors.lastname: Ebner
authors.forename: O
authors.initials: O
authors.lastname: Scheiner
authors.forename: G
authors.initials: G
authors.lastname: Boltz-Nitulescu
mesh_terms: D000328:Adult; D000485:Allergens / Q000276:immunology*; D017360:Arabidopsis / Q000737:chemistry / Q000276:immunology; D005260:Female; D006023:Glycoproteins / Q000276:immunology* / Q000378:metabolism; D006636:Histamine Release; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000175:diagnosis / Q000276:immunology*; D015151:Immunoblotting; D007073:Immunoglobulin E / Q000378:metabolism; D008297:Male; D010940:Plant Proteins / Q000276:immunology* / Q000378:metabolism; D011058:Pollen / Q000276:immunology; D011485:Protein Binding; D012882:Skin Tests; D014908:Triticum / Q000737:chemistry* / Q000276:immunology
chemical_list: D000485:Allergens; D006023:Glycoproteins; D010940:Plant Proteins; C058814:germin; D007073:Immunoglobulin E