title: Impact of glutathione on the allergenicity of the peach lipid transfer protein Pru p 3.
abstract: OBJECTIVE
  The allergenic potential of proteins can be altered under various physicochemical conditions. Glutathione (GSH) is a reducing agent that is used as an antioxidant in food products. We aimed to characterize the natural folding of peach proteins and test the allergenicity of reduced and natural Pru p 3, the major peach allergen.
  
  
  METHODS
  Pru p 3 was purified from peach, and its conformation was analyzed by means of circular dichroism. Using a thiol fluorescent probe, reduced proteins were detected in fresh peach. GSH-reduced Pru p 3 was tested in vitro for T-cell proliferation and in vivo using skin prick testing.
  
  
  RESULTS
  GSH-reduced Pru p 3 produced variable skin prick reactions in peach-allergic patients. The proliferative response of peripheral blood mononuclear cells from allergic patients to reduced Pru p 3 tended to be less intense, whereas secretion of the cytokines IFN-γ, IL-5, and IL-10 was comparable. In a pool of sera from peach-allergic patients, reduction hardly impaired IgE-binding. Moreover, the stability of reduced Pru p 3 to gastrointestinal digestion was similar to that of the natural form.
  
  
  CONCLUSIONS
  GSH can at least transiently reduce Pru p 3. We found that the effect of reduction on the allergenicity of Pru p 3 varied. Therefore, as an additive, GSH does not seem to eliminate the risk of reactions for peach-allergic patients.
authors.forename: C
authors.initials: C
authors.lastname: Gómez-Casado
authors.forename: L
authors.initials: L
authors.lastname: Tordesillas
authors.forename: J
authors.initials: J
authors.lastname: Kinkel
authors.forename: P
authors.initials: P
authors.lastname: Starkl
authors.forename: J
authors.initials: J
authors.lastname: Cuesta-Herranz
authors.lastname: Roth-Walter F
authors.forename: A
authors.initials: A
authors.lastname: Díaz-Perales
authors.forename: E
authors.initials: E
authors.lastname: Jensen-Jarolim
mesh_terms: D000328:Adult; D000485:Allergens / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D052179:Antigens, Plant / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D002352:Carrier Proteins / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D049109:Cell Proliferation; D002942:Circular Dichroism; D016207:Cytokines / Q000276:immunology; D005260:Female; D005512:Food Hypersensitivity / Q000276:immunology; D005978:Glutathione / Q000378:metabolism*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008297:Male; D008875:Middle Aged; D010940:Plant Proteins / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D011487:Protein Conformation; D027861:Prunus / Q000276:immunology* / Q000378:metabolism; D012882:Skin Tests
chemical_list: D000485:Allergens; D052179:Antigens, Plant; D002352:Carrier Proteins; D016207:Cytokines; D010940:Plant Proteins; C463181:Pru p 3 allergen; C030363:lipid transfer protein; D005978:Glutathione