title: The role of N-glycosylation in kiwi allergy.
abstract: The physical, biochemical, and immunological characteristics of plant allergens have been widely studied, but no definite conclusion has been reached about what actually makes a protein an allergen. In this sense, N-glycosylation is an exclusive characteristic of plant allergens not present in mammals and it could be implied in allergenic sensitization. With this aim, we evaluated and compared the allergenic activity of the protein fraction and the N-glycan fraction of the thaumatin-like protein and the main kiwi allergen, Act d 2. The natural allergen, Act d 2, was deglycosylated by trifluoromethanesulfonic acid treatment; the N-glycan fraction was obtained by extended treatment with proteinase K. N-glycan- and protein- fractions were recognized by specific IgE of kiwi-allergic patients. By contrast, the sugar moiety showed a reduced capacity to activate basophils and T cells, but not dendritic cells derived from patients' monocytes. Related to this, the production of cytokines such as IL6 and IL10 was increased by the incubation of dendritic cells with sugar moiety. Thus, the sugar moiety plays a significant role in sensitization, inducing the activation of antigen-presenting cells, but it is the protein fraction that is responsible for the allergic reactions.
authors.affiliation: Centre for Plant Biotechnology and Genomics U.P.M. - I.N.I.A., Campus de Montegancedo Pozuelo de Alarcón, Madrid, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Garrido-Arandia
authors.affiliation: Centre for Plant Biotechnology and Genomics U.P.M. - I.N.I.A., Campus de Montegancedo Pozuelo de Alarcón, Madrid, Spain.
authors.forename: Amaya
authors.initials: A
authors.lastname: Murua-García
authors.affiliation: Centre for Plant Biotechnology and Genomics U.P.M. - I.N.I.A., Campus de Montegancedo Pozuelo de Alarcón, Madrid, Spain.
authors.forename: Aranzazu
authors.initials: A
authors.lastname: Palacin
authors.affiliation: Centre for Plant Biotechnology and Genomics U.P.M. - I.N.I.A., Campus de Montegancedo Pozuelo de Alarcón, Madrid, Spain.
authors.forename: Leticia
authors.initials: L
authors.lastname: Tordesillas
authors.affiliation: Centre for Plant Biotechnology and Genomics U.P.M. - I.N.I.A., Campus de Montegancedo Pozuelo de Alarcón, Madrid, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Gómez-Casado
authors.affiliation: Allergy Service, Hospital Infanta Leonor Madrid, Spain.
authors.forename: Natalia
authors.initials: N
authors.lastname: Blanca-Lopez
authors.affiliation: Health Research Institute La Princesa (IP) Madrid, Spain.
authors.forename: Tania
authors.initials: T
authors.lastname: Ramos
authors.affiliation: Allergy Service, Hospital Infanta Leonor Madrid, Spain.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Canto
authors.affiliation: Health Research Institute La Princesa (IP) Madrid, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Blanco
authors.affiliation: IIS-Allergy Service, Fundación Jiménez Díaz Madrid, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Cuesta-Herranz
authors.affiliation: Centre for Plant Biotechnology and Genomics U.P.M. - I.N.I.A., Campus de Montegancedo Pozuelo de Alarcón, Madrid, Spain.
authors.forename: Rosa
authors.initials: R
authors.lastname: Sánchez-Monge
authors.affiliation: Centre for Plant Biotechnology and Genomics U.P.M. - I.N.I.A., Campus de Montegancedo Pozuelo de Alarcón, Madrid, Spain ; Biotechnology Department, ETSI de Montes, Technical University Madrid, Spain.
authors.forename: Luis F
authors.initials: LF
authors.lastname: Pacios
authors.affiliation: Centre for Plant Biotechnology and Genomics U.P.M. - I.N.I.A., Campus de Montegancedo Pozuelo de Alarcón, Madrid, Spain.
authors.forename: Araceli
authors.initials: A
authors.lastname: Díaz Perales
keywords: Act d 2; N-glycosylation; allergen sensitization; carbohydrate complex determinant; plant food allergy; thaumatin-like protein