Gastro-duodenal digestion products of the major peanut allergen Ara h 1 retain an allergenic potential

• Published in: Clinical and experimental allergy Vol. 36; no. 10; pp. 1281 - 1288
• Main Authors: Eiwegger, T., Rigby, N., Mondoulet, L., Bernard, H., Krauth, M.-T., Boehm, A., Dehlink, E., Valent, P., Wal, J. M., Mills, E. N. C., Szépfalusi, Z.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.10.2006; Blackwell
• Subjects: Allergens - immunology; Allergens - metabolism; Allergic diseases; Antigens, Plant; Ara h 1; Arachis hypogaea; Basophils - immunology; Biological and medical sciences; Case-Control Studies; Cell Proliferation; Cross Reactions; Cytokines - metabolism; Digestion; Digestive allergic diseases; Duodenum - metabolism; Electrophoresis, Polyacrylamide Gel; food allergy; Food Hypersensitivity - immunology; Food Hypersensitivity - metabolism; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Gastric Mucosa - metabolism; Glycoproteins - immunology; Glycoproteins - metabolism; Histamine Release; Humans; Immunoglobulin E - metabolism; Immunopathology; Medical sciences; Membrane Proteins; peanut allergy; Plant Proteins - immunology; Plant Proteins - metabolism; Research Design; T cell reactivity; T-Lymphocytes - immunology; Immunopathology; Food allergy; Peanut; Duodenum; Digestive system; Arachis hypogaea; Digestion; Small intestine; Ara h 1; peanut allergy; Immunology; Reactivity; Leguminosae; Dicotyledones; T cell reactivity; Angiospermae; T-Lymphocyte; Digestive diseases; Spermatophyta; Groundnut
• ISSN: 0954-7894; 1365-2222
• DOI: 10.1111/j.1365-2222.2006.02565.x

Summary Background The process of gastro‐duodenal digestion may play a role in determining the allergenic properties of food proteins. The sensitizing and allergenic potential of digestion products of highly degraded allergens, such as the major peanut allergen Ara h 1, is currently under debate. We evaluated the effect of in vitro gastro‐duodenal digestion of Ara h 1 on T cell reactivity and basophil histamine release. Methods An in vitro model of gastro‐duodenal digestion was used to investigate changes in the allergenic properties of Ara h 1 using in vitro assays monitoring T cell reactivity (proliferation, cytokine production) and histamine release of basophils from peanut allergic individuals. The digestion process was monitored using an SDS‐PAGE gel. Results In vitro gastric digestion led to rapid degradation of Ara h 1 into small fragments Mr L5600. Gastric digestion did not affect the ability of Ara h 1 to stimulate cellular proliferation. Gastro‐duodenal digestion significantly reduced its ability to stimulate clonal expansion (P<0,05; Wilxocon's signed rank test). The Th‐2 type cytokine polarization of T cells from peanut allergic donors (IFN‐γ/IL‐13 ratio and IFN‐γ/IL‐4 ratio of CFSElow CD4+ T cells) remained unchanged regardless of the level of digestion. Histamine release of basophils from peanut allergic individuals was induced to the same extent by native Ara h 1 and its digestion products. Conclusion Gastro‐duodenal digestion fragments of Ara h 1 retain T cell stimulatory and IgE‐binding and cross‐linking properties of the intact protein.