title: Characterization of lupin major allergens (Lupinus albus L.).
abstract: White lupin is considered to be a rich source of protein with a notable content of lysine and is being increasingly used in bakery, confectionery, snacks and pastry products due to its multifunctional properties, in addition to its potential hypocholesterolemic and hypoglycemic properties. However, lupin seed flour has been reported as a causative agent of allergic reactions, especially in patients with allergy to peanut since the risk of immunological cross-reactivity between lupin and peanut is higher than with other legumes. Previously, we had identified two proteins as major lupin allergens (34.5 and 20 kDa) as determined by IgE immunoblotting using sera of 23 patients with lupin-specific IgE. The aim of this study was to purify and characterize the two major lupin allergens. The results using in vitro IgE-binding studies and MS analysis have shown that the 34.5 kDa allergen (Lup-1) is a conglutin β (vicilin-like protein) while the 20 kDa allergen (Lup-2) corresponds to the conglutin α fraction (legumin-like protein). The high level of amino acid sequence homology of Lup-1 and Lup-2 with the major allergens of some legumes explains the IgE cross-reactivity and clinical cross-reactivity of lupin and other legumes.
authors.affiliation: Departamento de Tecnología de Alimentos, SGIT-INIA, Madrid, Spain. eva@inia.es
authors.forename: Eva
authors.initials: E
authors.lastname: Guillamón
authors.forename: Julia
authors.initials: J
authors.lastname: Rodríguez
authors.forename: Carmen
authors.initials: C
authors.lastname: Burbano
authors.forename: Mercedes
authors.initials: M
authors.lastname: Muzquiz
authors.forename: Mercedes M
authors.initials: MM
authors.lastname: Pedrosa
authors.forename: Beatriz
authors.initials: B
authors.lastname: Cabanillas
authors.forename: Jesús F
authors.initials: JF
authors.lastname: Crespo
authors.forename: Ana I
authors.initials: AI
authors.lastname: Sancho
authors.forename: E N Clare
authors.initials: EN
authors.lastname: Mills
authors.forename: Carmen
authors.initials: C
authors.lastname: Cuadrado
mesh_terms: D000485:Allergens / Q000032:analysis* / Q000276:immunology*; D000595:Amino Acid Sequence; D010367:Arachis / Q000737:chemistry; D003429:Cross Reactions / Q000276:immunology; D000939:Epitopes / Q000276:immunology; D007887:Fabaceae / Q000009:adverse effects / Q000737:chemistry; D005433:Flour / Q000009:adverse effects / Q000032:analysis; D005512:Food Hypersensitivity / Q000382:microbiology*; D037502:Galectin 3 / Q000276:immunology; D006801:Humans; D007073:Immunoglobulin E / Q000032:analysis / Q000276:immunology; D031297:Lupinus / Q000737:chemistry*; D008969:Molecular Sequence Data; D055314:Seed Storage Proteins / Q000032:analysis* / Q000276:immunology; D012639:Seeds / Q000009:adverse effects / Q000737:chemistry
chemical_list: D000485:Allergens; D000939:Epitopes; D037502:Galectin 3; D055314:Seed Storage Proteins; D007073:Immunoglobulin E; C015575:vicilin protein, plant