Background: The hazelnut major allergens identified to date are an 18-kd protein homologous to Bet v 1 and a 14-kd allergen homologous to Bet v 2. No studies have reported hazelnut allergens recognized in patients with positive double-blind, placebo-controlled food challenge (DBPCFC) results or in patients allergic to hazelnut but not to birch. Objective: We characterized the hazelnut allergens by studying the IgE reactivity of 65 patients with positive DBPCFC results and 7 patients with severe anaphylaxis to hazelnut. Methods: Hazelnut allergens were identified by means of SDS-PAGE and IgE immunoblotting. Further characterization was done with amino acid sequencing, evaluation of the IgE-binding properties of raw and roasted hazelnut with enzyme allergosorbent test inhibition, assessment of cross-reactivity with different allergens by means of immunoblotting inhibition, and purification by means of HPLC. Results: All the sera from the patients with positive DBPCFC results recognized an 18- and a 47-kd allergen; other major allergens were at molecular weights of 32 and 35 kd. Binding to the 18-kd band was inhibited by birch extract, indicating its homology with the birch major allergen, and abolished in roasted hazelnut. The 47-kd allergen is a sucrose-binding protein, the 35-kd allergen is a legumin, and the 32-kd allergen is a 2S albumin. Patients with severe anaphylactic reactions to hazelnut showed specific IgE reactivity to a 9-kd allergen, totally inhibited by purified peach lipid-transfer protein (LTP), which was heat stable and, when purified, corresponded to an LTP. Conclusions: The major allergen of hazelnut is an 18-kd protein homologous to Bet v 1, and the 9-kd allergen is presumably an LTP. Other major allergens have molecular weights of 47, 32, and 35 kd.
Identification of hazelnut major allergens in sensitive patients with positive double-blind placebo-controlled food challenge results / E.A. Pastorello, S. Vieths, V. Pravettoni, L. Farioli, C. Trambaioli, D. Fortunato, D. Lüttkopf, M. Calamari, R. Ansaloni, J. Scibilia, B.K. Ballmer-Weber, L.K. Poulsen, B. Wütrich, K. Skamstrup Hansen, A.M. Robino, C. Ortolani, A. Conti. - In: JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY. - ISSN 0091-6749. - 109:3(2002 Mar), pp. 563-570.
|Titolo:||Identification of hazelnut major allergens in sensitive patients with positive double-blind placebo-controlled food challenge results|
PASTORELLO, ELIDE ANNA (Primo)
|Parole Chiave:||food allergy ; hazelnut ; immunoblotting ; major allergen|
|Settore Scientifico Disciplinare:||Settore MED/09 - Medicina Interna|
|Data di pubblicazione:||mar-2002|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1067/mai.2002.121946|
|Appare nelle tipologie:||01 - Articolo su periodico|