title: What Characteristics Confer Proteins the Ability to Induce Allergic Responses? IgE Epitope Mapping and Comparison of the Structure of Soybean 2S Albumins and Ara h 2.
abstract: Ara h 2, a peanut 2S albumin, is associated with severe allergic reactions, but a homologous protein, soybean 2S albumin, is not recognized as an important allergen. Structural difference between these proteins might explain this clinical discrepancy. Therefore, we mapped sequential epitopes and compared the structure of Ara h 2, Soy Al 1, and Soy Al 3 (Gly m 8) to confirm whether structural differences account for the discrepancy in clinical responses to these two proteins. Commercially synthesized peptides covering the full length of Ara h 2 and two soybean 2S albumins were analyzed by peptide microarray. Sera from 10 patients with peanut and soybean allergies and seven non-atopic controls were examined. The majority of epitopes in Ara h 2 identified by microarray are consistent with those identified previously. Several regions in the 2S albumins are weakly recognized by individual sera from different patients. A comparison of allergenic epitopes on peanut and soybean proteins suggests that loop-helix type secondary structures and some amino acids with a large side chain including lone electron pair, such as arginine, glutamine, and tyrosine, makes the peptides highly recognizable by the immune system. By utilizing the peptide microarray assay, we mapped IgE epitopes of Ara h 2 and two soybean 2S albumins. The use of peptide microarray mapping and analysis of the epitope characteristics may provide critical information to access the allergenicity of food proteins.
authors.affiliation: Division of Pediatric Allergy and Immunology and the Jaffe Food Allergy Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA. snuhan@skku.edu.|Department of Medical Science, Sungkyunkwan University School of Medicine, Seoul 06351, Korea. snuhan@skku.edu.
authors.forename: Youngshin
authors.initials: Y
authors.lastname: Han
authors.affiliation: Division of Pediatric Allergy and Immunology and the Jaffe Food Allergy Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA. jing.s.lin@mssm.edu.
authors.forename: Jing
authors.initials: J
authors.lastname: Lin
authors.affiliation: Division of Pediatric Allergy and Immunology and the Jaffe Food Allergy Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA. luda.bardina@mssm.edu.
authors.forename: Ludmilla
authors.initials: L
authors.lastname: Bardina
authors.affiliation: Division of Pediatric Allergy and Immunology and the Jaffe Food Allergy Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA. galina.grishina@mssm.edu.
authors.forename: Galina A
authors.initials: GA
authors.lastname: Grishina
authors.affiliation: Department of Food Science and Engineering, Ewha Woman's University, Seoul 03760, Korea. dntree03@naver.com.
authors.forename: Chaeyoon
authors.initials: C
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Korea University College of Medicine, Seoul 02841, Korea. wonny508@korea.ac.kr.
authors.forename: Won Hee
authors.initials: WH
authors.lastname: Seo
authors.affiliation: Division of Pediatric Allergy and Immunology and the Jaffe Food Allergy Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA. hugh.sampson@mssm.edu.
authors.forename: Hugh A
authors.initials: HA
authors.lastname: Sampson
mesh_terms: D055516:2S Albumins, Plant / Q000276:immunology*; D000485:Allergens / Q000276:immunology; D018604:Epitope Mapping; D000939:Epitopes / Q000276:immunology*; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology*; D007073:Immunoglobulin E / Q000276:immunology*; D030262:Soybean Proteins / Q000276:immunology; D013025:Glycine max / Q000737:chemistry / Q000276:immunology
chemical_list: D055516:2S Albumins, Plant; D000485:Allergens; D000939:Epitopes; D030262:Soybean Proteins; D007073:Immunoglobulin E
keywords: 2S albumins; Ara h 2; epitope mapping; peptide microarray; soybean