Immunoglobulin E specific for cat allergens (Cat-specific IgE)

Immunoglobulin E (IgE) specific for cat allergens, primarily targeting the major secretoglobin Fel d 1, is the central mediator of cat-induced allergic diseases (Source: NIH, PubMed). In sensitized individuals, these specific IgE antibodies are produced by B cells and subsequently bind to high-affinity FcεRI receptors on the surface of mast cells and basophils (Source: StatPearls). Upon re-exposure to cat dander, the allergen cross-links these surface-bound IgE molecules, triggering the immediate release of inflammatory mediators such as histamine, leukotrienes, and prostaglandins (Source: Journal of Allergy and Clinical Immunology). This physiological response results in the clinical symptoms of allergic rhinitis, conjunctivitis, and allergic asthma. Therapeutic interventions focus on neutralizing circulating IgE using monoclonal antibodies like Omalizumab or modulating the immune system's long-term response through allergen-specific immunotherapy (Source: FDA, World Allergy Organization). By reducing the availability of specific IgE or blocking its interaction with receptors, these treatments effectively diminish the allergic inflammatory cascade.

Other names

Cat-specific IgEFel d 1-specific IgEsIgE to cat danderAnti-cat IgE antibodiesImmunoglobulin E specific for Felis catus allergens

Monoclonal antibodies such as Omalizumab bind to the Cε3 domain of circulating IgE, which is the same site required for binding to the high-affinity IgE receptor (FcεRI) on mast cells and basophils (Source: PubChem, FDA). This sequestration prevents the IgE from sensitizing these effector cells. Additionally, the reduction in free serum IgE leads to a down-regulation of FcεRI expression on the cell surface, further raising the threshold for allergen-induced activation (Source: NIH). Allergen-specific immunotherapy (AIT) works by inducing immune tolerance through the production of IgG4 'blocking' antibodies that compete with IgE for allergen binding and by promoting regulatory T cell (Treg) activity (Source: World Allergy Organization).