title: Identification of IgE-binding peptides in hen egg ovalbumin digested in vitro with human and simulated gastroduodenal fluids.
abstract: The digestibility of the major egg allergen ovalbumin (OVA, Gal d 2) with human and simulated digestive fluids was assessed. Degradation of OVA was faster when treated with human fluids, particularly following duodenal digestion, leading to gastrointestinal digests with lower IgE binding. Gastric digestion with both systems yielded 52 identical cleavage sites and a similar peptide pattern with 47 peptides in common. Subsequent duodenal digestion showed that the human fluid released fewer and shorter peptides. Several high-frequency IgE-binding epitopes were detected among the fragments of molecular mass lower than 3 kDa identified in the digests: OVA (141-154) and OVA (164-176) in the gastrointestinal digests produced with human fluids; and OVA (125-134), OVA (159-172), OVA (141-154), OVA (188-198), OVA (326-336), and OVA (370-385) in the gastrointestinal digests produced with simulated fluids. The high binding frequency of the fragment OVA (370-385), which reacted with 80% of the sera from allergic patients used, was noteworthy.
authors.affiliation: Instituto de Investigación en Ciencias de la Alimentación (CIAL), CSIC-UAM , Nicolás Cabrera 9, 28049 Madrid, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Benedé
authors.forename: Iván
authors.initials: I
authors.lastname: López-Expósito
authors.forename: Rosina
authors.initials: R
authors.lastname: López-Fandiño
authors.forename: Elena
authors.initials: E
authors.lastname: Molina
mesh_terms: D000485:Allergens / Q000737:chemistry / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D002645:Chickens; D004063:Digestion; D004386:Duodenum / Q000378:metabolism*; D004531:Eggs / Q000032:analysis; D005260:Female; D005750:Gastric Juice / Q000378:metabolism; D041981:Gastrointestinal Tract / Q000378:metabolism; D006801:Humans; D007073:Immunoglobulin E / Q000737:chemistry* / Q000378:metabolism; D066298:In Vitro Techniques; D008954:Models, Biological; D008969:Molecular Sequence Data; D010047:Ovalbumin / Q000737:chemistry* / Q000378:metabolism; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism; D011485:Protein Binding
chemical_list: D000485:Allergens; D010455:Peptides; D007073:Immunoglobulin E; D010047:Ovalbumin
keywords: IgE; egg allergy; epitope; human digestive fluids; in vitro digestion; ovalbumin