Project Number: 6054-43440-046-000-D
Project Type: In-House Appropriated
Start Date: Jul 7, 2015
End Date: Jul 6, 2020
Obective 1: Enable new commercial methods to reduce or eliminate the allergenic properties of peanut and tree nut products. Objective 2: Integrate overall oral and food allergenic properties of native and recombinant allergens with cross-reactivity among nuts, between nuts and pollens, and with pre and postharvest processing. Objective 3: Integrate allergenic properties and molecular changes with commercial tree nut development. Objective 4: Enable new commercial immunoassays for detection of allergens in processed foods.
The immunoglobulin E (IgE) binding sites that are responsible for the symptoms of allergic disease and cross-reactivity among peanut, tree nut and pollen allergens will be identified with peptide microarray technology. The IgE epitopes will be modeled on the surface of allergen structures to identify location and common or cross-reactive sequences and structural regions of allergens among nuts and pollens. Simultaneously, peanuts, tree nuts or purified allergens thereof (recombinant or native) will be subjected to existing and novel processing techniques (i.e. heat, chemical and enzymatic treatment). New allergens or changes in allergenic properties of existing allergens due to the processing methods will be identified by immunoassays with serum (containing IgE antibodies) from peanut and or tree nut allergic individuals. Proteins found to be immunologically altered by processing will be assessed within the food matrix or they will be purified and analyzed for alterations in size, structure, digestibility, binding to various antibodies, including, serum IgE, known anti-processing reaction products, and allergen specific antibodies. The specific amino acid residues, or peptides thought to be modified during different processing events, and to contribute to altered allergenic properties will be identified by mass spectrometry. Understanding the molecular basis of processing-induced alterations of allergens with respect to the IgE binding sights will guide the development of processing technologies towards reduced allergenicity of nuts and products thereof. This knowledge will also contribute to the development of better detection tools and labeling practices for industry and regulatory agencies resulting in better protection of consumers. As a possible early interventional method to reduce the allergenic potential of nuts, the expression and accumulation patterns of allergens in a model tree-nut (pecan) will be studied under various conditions, which may allow interference with their accumulation in the future.