Immunoglobulin E antibody (allergen-specific) (IgE)

Immunoglobulin E antibody (IgE) is a Y-shaped protein produced by plasma cells as part of the adaptive immune system. Allergen-specific IgEs are antibodies that recognize particular environmental antigens known as allergens. When these antibodies bind their specific allergen and attach to high-affinity receptors (FcεRI) on mast cells or basophils, they trigger cell activation and release mediators such as histamine—leading to immediate hypersensitivity reactions including urticaria, rhinitis, asthma exacerbations, or even systemic anaphylaxis. The same mechanism underlies defense against certain parasites but can become pathological in allergic disease. Measurement of serum allergen-specific IgEs is used clinically for allergy diagnosis; omalizumab is a monoclonal antibody drug that targets circulating free IgEs to reduce symptoms in severe allergic asthma and chronic urticaria patients. Safety concerns include the potential for severe acute reactions if large-scale degranulation occurs following widespread cross-linking by multivalent allergens.

Other names

Allergen-specific IgEIgE antibodyImmunoglobulin E (IgE)

Monoclonal antibodies that bind free IgE and prevent its interaction with FcεRI on effector cells, thereby reducing allergic inflammation and symptoms