title: Proteomic identification of allergenic seed proteins, napin and cruciferin, from cold-pressed rapeseed oils.
abstract: In Finland and France atopic children commonly react to seeds of oilseed rape and turnip rape in skin prick tests (SPT) and open food challenges. These seeds are not as such in dietary use and therefore the routes of sensitization are unknown. Possible allergens were extracted from commercial cold-pressed and refined rapeseed oils and identified by gel-based tandem nanoflow liquid chromatography mass spectrometry (LC-MS/MS). Napin (a 2S albumin), earlier identified as a major allergen in the seeds of oilseed rape and turnip rape, and cruciferin (an 11S globulin), a new potential seed allergen, were detected in cold-pressed oils, but not in refined oils. Pooled sera from five children sensitized or allergic to oilseed rape and turnip rape seeds reacted to these proteins from cold-pressed oil preparations and individual sera from five children reacted to these proteins extracted from the seeds when examined with IgE immunoblotting. Hence cold-pressed rapeseed oil might be one possible route of sensitization for these allergens.
authors.affiliation: Haartman Institute, Department of Bacteriology and Immunology, University of Helsinki, Finland; Immune Response Unit, National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: T J
authors.initials: TJ
authors.lastname: Puumalainen
authors.affiliation: Unit of Immunotoxicology, Finnish Institute of Occupational Health, Helsinki, Finland.
authors.forename: A
authors.initials: A
authors.lastname: Puustinen
authors.affiliation: Department of Dermatology, Central Finland Health Care District, Jyväskylä, Finland.
authors.forename: S
authors.initials: S
authors.lastname: Poikonen
authors.affiliation: Department of Dermatology, Tampere University and University Hospital, Tampere, Finland.
authors.forename: K
authors.initials: K
authors.lastname: Turjanmaa
authors.affiliation: Immune Response Unit, National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: T
authors.initials: T
authors.lastname: Palosuo
authors.affiliation: Haartman Institute, Department of Bacteriology and Immunology, University of Helsinki, Finland; Department of Occupational Medicine, Haukeland University Hospital, Bergen, Norway. Electronic address: kirsi.vaali@helsinki.fi.
authors.forename: K
authors.initials: K
authors.lastname: Vaali
mesh_terms: D000485:Allergens / Q000737:chemistry* / Q000276:immunology; D029688:Brassica napus / Q000737:chemistry*; D002648:Child; D005229:Fatty Acids, Monounsaturated; D005512:Food Hypersensitivity; D006801:Humans; D010938:Plant Oils / Q000737:chemistry*; D040901:Proteomics / Q000379:methods; D000074262:Rapeseed Oil
chemical_list: D000485:Allergens; D005229:Fatty Acids, Monounsaturated; D010938:Plant Oils; D000074262:Rapeseed Oil
keywords: 11S globulin; 2S albumin; Canola; Food allergy; Oilseed rape; Proteomics; Turnip rape; Vegetable oil