Heat processing of peanut seed enhances the sensitization potential of the major peanut allergen Ara h 6. Issue 12 (6th October 2016)

• Record Type: Journal Article
• Authors: Guillon, Blanche; Bernard, Hervé; Drumare, Marie‐Françoise; Hazebrouck, Stéphane; Adel‐Patient, Karine
• Is Part Of: Molecular nutrition & food research. Volume 60:Issue 12(2016)
• Page Start: 2722
• Page End: 2735
• Publication Date: 2016-10-06
• Subjects: Allergenicity assessment -- Ara h 6 -- Food processing -- IgE induction -- in vitro digestion test; Food -- Biotechnology -- Periodicals; Food -- Microbiology -- Periodicals; Nutrition -- Periodicals; Food -- Toxicology -- Periodicals; Nutrition -- Periodicals; Food Microbiology -- Periodicals; Food Technology -- Periodicals; Molecular Biology -- Periodicals; 664.0705
• DOI: 10.1002/mnfr.201500923
• Languages: English
• ISSNs: 1613-4125

Abstract

Abstract : Different structures are responsible for sensitization and elicitation to Ara h 6 and heating is essential to sensitization potency of Ara h 6. Roasting of peanut seed induces partial denaturation and cross‐linking of Ara h 6 with other peanut allergens, notably Ara h 1. The increased susceptibility to proteolytic degradation of the corresponding structures of Ara h 6 increases the immunogenicity of Ara h 6. Conversely, free monomeric Ara h 6, also found in peanut seed, is not immunogenic but is the support of IgE binding and elicitation of the allergic reaction. Abstract : Scope: Processing of food has been shown to impact IgE binding and functionality of food allergens. In the present study, we investigated the impact of heat processing on the sensitization capacity of Ara h 6, a major peanut allergen and one of the most potent elicitors of the allergic reaction. Methods and results: Peanut extracts obtained from raw or heat‐processed peanut and some fractions thereof were biochemically and immunochemically characterized. These extracts/fractions, purified Ara h 6, or recombinant Ara h 6 including Ara h 6 mutants lacking disulfide bridges were used in in vitro digestion tests and mouse models of experimental sensitization. Peanut roasting led to the formation of complexes of high molecular weight, notably between Ara h 6 and Ara h 1, which supported the induction of IgE specific to native Ara h 6. On the contrary, a fraction containing free monomeric 2S albumins or purified native Ara h 6 displayed no intrinsic allergenicity. In addition to complex formation, heat denaturation and/or partial destabilization enhanced Ara h 6 immunogenicity and increased its sensitivity to digestion. Conclusion: These results suggest that sensitization potency and IgE binding capacity can be supported by different structures, modified and/or produced during food processing in interaction with other food constituents.