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Along with peanuts and shellfish, tree nuts are one of the food allergens most often linked to anaphylaxis — a serious, rapid-onset allergic reaction that may be ... to determine the presence ofallergen-specific immunoglobulin E, an antibody that binds to allergens and triggers the release of chemicals that cause symptoms
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Usually they are affected by a certain PROTEIN in a food or ingredient, such as peanuts and/or shellfish.