Polyphenol-Rich pomegranate juice reduces IgE binding to cashew nut allergens

Authors: LI, YICHEN - US Department Of Energy; Mattison, Chris

Submitted to: Journal of the Science of Food and Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/22/2017
Publication Date: 3/15/2018
Citation: Li, Y., Mattison, C.P. 2018. Polyphenol-Rich pomegranate juice reduces IgE binding to cashew nut allergens. Journal of the Science of Food and Agriculture. 98:1632-1638.

Interpretive Summary: People suffering from food allergy can have a reduced quality of life. Cashew nuts commonly cause severe reactions and only small amounts are needed. Polyphenols are large naturally occurring compounds found in many fruits and vegetables. Polyphenol rich juices and polyphenol compounds have been demonstrated to complex with peanut allergens. The interaction between cashew nut allergens and polyphenol rich juices from pomegranate (POM), blueberry (BB), and concord grape (CG) were evaluated biochemically and immunologically. POM juice showed a greater capacity to form large complexes with cashew proteins. A sharp increase in cashew protein extract particle size was observed after incubation with POM juice, and cashew proteins were removed from the solution after treatment with POM juice. Immunoassays demonstrated reduced antibody binding to cashew allergens treated with POM juice. These observations support the formation of complexes between polyphenols and cashew proteins that may prevent antibody recognition of cashew allergens. POM juice treatment of cashew extract could effectively reduce antibody binding, and these findings could be applied to the development of less allergenic cashew nut products and oral immunotherapy.

Technical Abstract: Cashew nut allergy is mediated by IgE binding to seed-storage proteins including Ana o 1, 2, and 3. Cashew nuts commonly cause severe reactions and only small amounts are needed. Polyphenol rich juices and polyphenol compounds have been demonstrated to complex with peanut allergens. The interaction between cashew nut allergens Ana o 1, 2, and 3 with polyphenol rich juices from pomegranate (POM), blueberry (BB), and concord grape (CG) was evaluated biochemically and immunologically. Polyphenols from POM juice showed a greater capacity to form complexes with cashew proteins. Dynamic light scattering (DLS) demonstrated a sharp increase in cashew protein extract particle size from 10-500 nm to approximately 3580 nm, and fewer cashew proteins were resolved by electrophoresis after treatment with POM juice. Immunoblot and ELISA assays demonstrated reduced IgG and IgE binding to cashew allergens treated with POM juice, although Ana o 3 was not bound as well as Ana o 1 and 2. These observations support the formation of complexes between polyphenol and cashew proteins that can prevent antibody recognition of cashew allergens. POM juice treatment of cashew extract effectively reduces antibody binding, and these findings could be applied to the development of less allergenic cashew nut products and oral immunotherapy.