Different Profiles of Wheat Antigens Are Recognised by Patients Suffering from Coeliac Disease and IgE-Mediated Food Allergy

Abstract

Background: Dietary intake of wheat can cause two distinct immunologically mediated diseases with severe gastrointestinal manifestations, coeliac disease (CD) and IgE-mediated food allergy. The pathomechanisms underlying these diseases are different, but the profile of the target antigens in wheat has not been compared for the two diseases. Methods: We compared IgA- and IgE-reactive antigens in wheat using sera from patients with coeliac disease (n = 35) and food allergy to wheat (n = 16) by one- and two-dimensional immunoblotting. Furthermore, the IgG subclass (IgG1–IgG4) reactivity to wheat antigens was studied by enzyme-linked immunosorbent assay. Results: IgA antibodies from CD patients and IgE antibodies from allergic patients recognised distinct profiles of wheat antigens. Furthermore, the IgG subclass responses to wheat antigens were different in CD and wheat-allergic patients. Conclusion: This study thus demonstrates that wheat contains antigens/epitopes which are preferentially recognised by CD patients, whereas others elicit IgE-mediated food allergy. This finding suggests that the nature of a food antigen may influence the quality of the pathological immune response in the gut and has implications for the diagnosis and therapy of hypersensitivity to wheat.

Evaluation of an in vitro Mast Cell Degranulation Test in the Context of Food Allergy to Wheat

“…Characterization of IgE responses to wheat flour allergens showed a broad spectrum [48]. It raised questions about the ability of all these antigens to activate mast cells in view of their clinical relevance.…”

Molecular and Immunological Characterization of a Wheat Serine Proteinase Inhibitor as a Novel Allergen in Baker's Asthma

“…Michael were obtained from the Ö sterreichische Agentur für Gesundheit und Ernährungssicherheit and planted in a glasshouse. Immature seeds were harvested 7,10,15,20,25,30, and 35 days after the onset of pollination directly into liquid nitrogen and stored at Ϫ80°C until use. Wheat pollen was obtained from Allergon.…”

“…Additionally, serum from a nonallergic individual, sera from four patients suffering from food allergy to wheat, and and sera from four grass pollen-allergic patients without baker's asthma but with serum IgE reactivity to wheat and rye flour were included in the experiments (Table II). Sera from grass pollen-allergic patients had been analyzed for total serum IgE levels and IgE-specific for timothy grass pollen by the CAP-FEIA system, and patients with food allergy to wheat were characterized as described previously (30). The specificity of the clone 10-derived allergen for baker's asthma was confirmed by testing additional sera from 20 celiac disease patients, 119 food allergic patients, 23 grass pollen-allergic patients, and 25 baker's asthma patients by gene chip analysis (C. Constantin and R. Valenta, unpublished data).…”

“…After blocking with 1% (w/v) BSA in PBS, 0.05% (v/v) Tween 20 (PBST), plates were incubated with sera diluted 1/50 in PBST, 0.5% (w/v) BSA for measurement of IgG1, IgG2, IgG3, and IgG4 as described (34). Bound Abs were detected by incubating first with monoclonal mouse anti-human IgG subclass Abs (BD Biosciences) diluted 1/1000 in PBST, 0.5% (w/v) BSA, and then with a horseradish-peroxidase-coupled sheep anti-mouse antiserum (GE Healthcare) diluted 1/2000 in PBST, 0.5% (w/v) BSA as previously described (30). All determinations were performed as duplicates, and results are expressed as mean values.…”

“…To remove insoluble particles, the extracts were centrifuged at 10,000 ϫ g for 10 min at 4°C, and the supernatants were stored in aliquots at Ϫ20°C. Additionally, a PBS-protein extract from wheat seeds was prepared as previously described (30). Triticum aestivum pollen (500 mg) was extracted at 4°C overnight in 5 ml PBS, 2 mM EDTA, 1 mM PMSF.…”