Heat-induced alterations in cashew allergen solubility and IgE binding

Publication date: Available online 14 January 2016 Source:Toxicology Reports Author(s): Christopher P. Mattison, Yvette Bren-Mattison, Barry Vant-Hull, Aurora M. Vargas, Richard L. Wasserman, Casey C. Grimm Cashew nuts are an increasingly common cause food allergy. We compared the soluble protein profile of cashew nuts following heating. SDS-PAGE indicated that heating can alter the solubility of cashew nut proteins. The 11S legumin, Ana o 2, dominates the soluble protein content in ready to eat and mildly heated cashew nuts. However, we found that in dark-roasted cashew nuts, the soluble protein profile shifts and the 2S albumin Ana o 3 composes up to 40% of the soluble protein. Analysis of trypsin-treated extracts by LC/MS/MS indicated changes in the relative number and intensity of peptides. The cumulative intensity of the 5 most commonly observed Ana o 1 and 2 peptides were altered by heating, while those of the 5 most commonly observed Ana o 3 peptides remained relatively constant. ELISA binding experiments indicated that there was a decrease in rabbit IgG and human serum IgE binding to soluble cashew proteins extracts following heating. Our findings indicate heating can alter the solubility of cashew allergens, resulting in altered IgE binding. Our results support the use of both Ana o 2 and Ana o 3as potential cashew allergen diagnostic targets.
Source: Toxicology Reports - Category: Toxicology Source Type: research