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True Food Allergies

As noted above, true food allergies involve abnormal immunological responses of the body to substances in foods. The allergens are typically naturally occurring proteins that are present in certain foods. However, the true food allergies can be divided into two categories: antibody-mediated or cell-mediated reactions. The antibody-mediated food allergies are usually mediated by allergen-specific immunoglobulin E (IgE) antibodies, while cell-mediated food allergies are mediated by sensitized lymphocytes (2).

IgE-Mediated Food Allergies

IgE-mediated food allergies are also referred to as immediate hypersensitivity reactions. Symptoms develop within a few minutes to a few hours after the inadvertent ingestion of the offending food. In IgE-mediated food allergies (Fig. 14.1), susceptible individuals will form allergen-specific IgE antibodies upon exposure to an allergen (8). The IgE attaches itself to mast cells in various tissues of the body and basophils in the blood. Mast cells and basophils are specialized cells in the body that contain a host of physiologically active molecules (mediators) including histamine, prostaglandins and leukotrienes. The process of IgE

Mechanism of IgE-mediated allergic reactions to food.

Mechanism of IgE-mediated allergic reactions to food.

Food Allergies

Food Allergies

Peanuts can leave you breathless. Cat dander can lead to itchy eyes, a stuffy nose, coughing and sneezing. And most of us have suffered through those seasonal allergies with horrible pollen counts. Learn more...

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