title: Effects of autoclaving and high pressure on allergenicity of hazelnut proteins.
abstract: BACKGROUND
  Hazelnut is reported as a causative agent of allergic reactions. However it is also an edible nut with health benefits. The allergenic characteristics of hazelnut-samples after autoclaving (AC) and high-pressure (HHP) processing have been studied and are also presented here. Previous studies demonstrated that AC treatments were responsible for structural transformation of protein structure motifs. Thus, structural analyses of allergen proteins from hazelnut were carried out to observe what is occurring in relation to the specific-IgE recognition of the related allergenic proteins. The aims of this work are to evaluate the effect of AC and HHP processing on hazelnut in vitro allergenicity using human-sera and to analyse the complexity of hazelnut allergen-protein structures.
  
  
  METHODS
  Hazelnut-samples were subjected to AC and HHP processing. The specific IgE- reactivity was studied in 15 allergic clinic-patients via western blotting analyses. A series of homology-based-bioinformatics 3D-models (Cora 1, Cora 8, Cora 9 and Cora 11) were generated for the antigens included in the study to analyse the co mplexity of their protein structure. This study is supported by the Declaration of Helsinki and subsequent ethical guidelines.
  
  
  RESULTS
  A severe reduction in vitro in allergenicity to hazelnut after AC processing was observed in the allergic clinic-patients studied. The specific-IgE binding of some of the described immunoreactive hazelnut protein-bands: Cora 1 ~18KDa, Cora 8 ~9KDa, Cora 9 ~35-40KDa and Cora 11 ~47-48 KDa decreases. Furthermore a relevant glycosylation was assigned and visualized via structural analysis of proteins (3D-modelling) for the first time in the protein-allergen Cora 11 showing a new role which could open a new door for allergenicity-unravellings.
  
  
  CONCLUSIONS
  Hazelnut allergenicity-studies in vivo via Prick-Prick and other means using AC processing are crucial to verify the data we observed via in vitro analyses. Glycosylation studies provided us with clues to elucidate, in the near future, mechanisms of the structures that contribute to hazelnut allergenicity, which thus, in turn, help alleviate food allergens.
authors.affiliation: Centro de Investigación (i + 12) del Hospital Universitario 12 de Octubre, Avda de Córdoba, s/n, 28041, Madrid, Spain. elena.lopez.villar@gmail.com.
authors.forename: Elena
authors.initials: E
authors.lastname: López
authors.forename: Carmen
authors.initials: C
authors.lastname: Cuadrado
authors.forename: Carmen
authors.initials: C
authors.lastname: Burbano
authors.forename: Maria Aranzazu
authors.initials: MA
authors.lastname: Jiménez
authors.forename: Julia
authors.initials: J
authors.lastname: Rodríguez
authors.forename: Jesús F
authors.initials: JF
authors.lastname: Crespo