Covalent polyphenol modification of a reactive cysteine in the major apple allergen Mal d 1.

Naturally occurring polyphenols can modify the molecular properties of food allergens. For the major apple allergen Mal d 1 it has been postulated that chemical reactions with polyphenols cause permanent changes in the tertiary structure, causing a loss of conformational IgE epitopes and reducing allergenicity. In our study, we investigated the effect that reactions with oxidized polyphenols have on the structure of Mal d 1 by mass spectrometry and NMR spectroscopy.

Ascorbylation of a Reactive Cysteine in the Major Apple Allergen Mal d 1.

The protein Mal d 1 is responsible for most allergic reactions to apples () in the northern hemisphere. Mal d 1 contains a cysteine residue on its surface, with its reactive side chain thiol exposed to the surrounding food matrix. We show that, in vitro, this cysteine residue is prone to spontaneous chemical modification by ascorbic acid (vitamin C).

Oral birch pollen immunotherapy with apples: Results of a phase II clinical pilot study.

Background: Seventy percent of patients suffering from birch pollen allergy (BPA) develop a pollen-related food allergy (prFA), especially to apples, due to a clinically relevant cross-reactivity between the major allergen in birch Bet v 1 and Mal d 1 in apples. Therefore allergen-specific immunotherapy with fresh apples (AITA) could be a promising natural treatment of both BPA and prFA.

Objective: To assess the clinical efficacy of immunotherapy by daily apple consumption for patients with BPA and prFA.

Inverse relation between structural flexibility and IgE reactivity of Cor a 1 hazelnut allergens.

A major proportion of allergic reactions to hazelnuts (Corylus avellana) are caused by immunologic cross-reactivity of IgE antibodies to pathogenesis-related class 10 (PR-10) proteins. Intriguingly, the four known isoforms of the hazelnut PR-10 allergen Cor a 1, denoted as Cor a 1.0401-Cor a 1.