For the most part, this system works well. The body recognizes cells that are part of itself and cells that are not, and recognizes cells that are threatening (e.g., viruses and bacteria) and cells that are harmless (e.g., food and pollen). However, in allergic individuals, the immune system identifes a food as a germ or antigen and produces antibodies -- specifically, Immunoglobulin E, or IgE -- to it. A food that has been primed in this manner is called an allergen. The resulting IgE/mast cell complex recognizes and binds to allergens, and this reaction stimulates the release of histamine and other chemicals.
Allergic Reactions
When the body is exposed to an allergen, Immunoglobulin IgE attaches to what it perceives as a foreign invader and releases a number of chemicals as a form of attack. The most well-known chemical, which is responsible for a host of allergic symptoms, released in this reaction is called histamine. (Many drugs that treat allergies are called antihistamines because they treat the effects of this chemical). Histamine induces tissue swelling and can cause a host of local and systemic symptoms, including hives, rhinitis, and vomiting.
When the body is exposed to an allergen, Immunoglobulin IgE attaches to what it perceives as a foreign invader and releases a number of chemicals as a form of attack. The most well-known chemical, which is responsible for a host of allergic symptoms, released in this reaction is called histamine. (Many drugs that treat allergies are called antihistamines because they treat the effects of this chemical). Histamine induces tissue swelling and can cause a host of local and systemic symptoms, including hives, rhinitis, and vomiting.
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