A relatively new form of therapy for IgE-mediated allergic diseases is the periodic injection of patients with anti-IgE antibody. This antibody binds to the Fc portion of IgE antibodies, and prevents the IgE antibodies from binding to both high affinity and low affinity IgE receptors on inflammatory cells. IgE bound to the high affinity IgE receptor on mast cells and basophils stimulates degranulation of these cells and their production of inflammatory mediators, following antigen encounter. In contrast, the low affinity IgE receptor is expressed on dendritic cells, and functions to trap allergen-IgE complexes for uptake, degradation, and presentation to T cells. Given these functions, individuals treated with this anti-IgE therapy would be expected to show:

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Quizplus · Accepted Answer

The periodic injection of anti-IgE antibodies would block the binding of IgE to mast cells and basophils, preventing their degranulation and the release of inflammatory mediators. This would result in a reduced allergic response and no progressive worsening of the disease. However, this therapy would not cure the underlying allergy or prevent future sensitization, so rebound reactions might occur but would not cause as severe symptoms as before the therapy. The therapy would also be expected to have a beneficial effect on allergic asthma, as it involves the inflammation of the airways, but may have limited effects on food or skin allergies which involves mast cells located in the tissue instead of blood circulation. Anti-IgE therapy would not affect mucus production in the airways or GI tract, as it does not target the production of the mucus. Lastly, the therapy would not affect the response to helminthic parasite infections, as this is mediated by different types of immune cells and antibodies.

A Relatively New Form of Therapy for IgE-Mediated Allergic Diseases