title: Pomegranate ( Punica granatum L.) expresses several nsLTP isoforms characterized by different immunoglobulin E-binding properties.
abstract: BACKGROUND
  Pomegranate allergy is associated with sensitization to non-specific lipid transfer proteins (nsLTPs). Our aim was to identify and characterize the non-specific nsLTPs expressed in pomegranate at the molecular level and to study their allergenic properties in terms of immunoglobulin E (IgE)-binding and cross-reactivity with peach nsLTP (Pru p 3).
  
  
  METHODS
  A non-equilibrium two-dimensional (2-D) electrophoretic approach based on acid-urea PAGE and sodium dodecyl sulfate PAGE was set up to separate pomegranate nsLTPs. Their immunoreactivity was tested by immunoblotting carried out with anti-Pru p 3 polyclonal antibodies and sera from pomegranate-allergic patients. For final identification, pomegranate nsLTPs were purified by chromatography and subjected to trypsin digestion and mass spectrometry (MS) analysis. For this purpose, the sequences obtained by cDNA cloning of three pomegranate nsLTPs were integrated in the database that was subsequently searched for MS data interpretation.
  
  
  RESULTS
  Four nsLTPs were identified by 2-D immunoblotting. The detected proteins showed different IgE-binding capacity and partial cross-reactivity with Pru p 3. cDNA cloning and MS analyses led to the identification of three nsLTP isoforms with 66-68% amino acid sequence identity named Pun g 1.0101, Pun g 1.0201 and Pun g 1.0301.
  
  
  CONCLUSIONS
  By 2-D electrophoresis, we could separate different nsLTP isoforms possessing different IgE-binding properties, which might reflect peculiar allergenic potencies. The contribution of Pru p 3 to prime sensitization is not central as in other plant nsLTPs.
authors.affiliation: Department of Biotechnology, University of Verona, Verona, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Bolla
authors.forename: Sara
authors.initials: S
authors.lastname: Zenoni
authors.forename: Stephan
authors.initials: S
authors.lastname: Scheurer
authors.forename: Stefan
authors.initials: S
authors.lastname: Vieths
authors.forename: Maria Del Mar
authors.initials: Mdel M
authors.lastname: San Miguel Moncin
authors.forename: Mario
authors.initials: M
authors.lastname: Olivieri
authors.forename: Andrea
authors.initials: A
authors.lastname: Antico
authors.forename: Marta
authors.initials: M
authors.lastname: Ferrer
authors.forename: Felicia
authors.initials: F
authors.lastname: Berroa
authors.forename: Ernesto
authors.initials: E
authors.lastname: Enrique
authors.forename: Linda
authors.initials: L
authors.lastname: Avesani
authors.forename: Francesco
authors.initials: F
authors.lastname: Marsano
authors.forename: Gianni
authors.initials: G
authors.lastname: Zoccatelli
mesh_terms: D000328:Adult; D000485:Allergens / Q000235:genetics / Q000276:immunology; D000595:Amino Acid Sequence; D052179:Antigens, Plant / Q000276:immunology; D002352:Carrier Proteins / Q000235:genetics* / Q000276:immunology*; D003429:Cross Reactions / Q000276:immunology; D018076:DNA, Complementary / Q000235:genetics; D005260:Female; D005512:Food Hypersensitivity / Q000235:genetics / Q000276:immunology; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology*; D029561:Lythraceae / Q000235:genetics / Q000276:immunology*; D008875:Middle Aged; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics / Q000276:immunology; D020033:Protein Isoforms / Q000235:genetics* / Q000276:immunology*; D027861:Prunus / Q000235:genetics / Q000276:immunology; D016415:Sequence Alignment; D055815:Young Adult
chemical_list: D000485:Allergens; D052179:Antigens, Plant; D002352:Carrier Proteins; D018076:DNA, Complementary; D010940:Plant Proteins; D020033:Protein Isoforms; C072087:sterol carrier proteins; D007073:Immunoglobulin E