High-affinity immunoglobulin epsilon receptor I (FcεRI) (FcεRI)

The complex formed by Fel d 1-specific IgE bound to the high-affinity IgE receptor (FcεRI) on mast cells and basophils is the primary molecular trigger for cat-allergic reactions (Source: PubMed, PMID: 30102974). FcεRI is a multimeric receptor that binds the Fc region of IgE antibodies with extremely high affinity, effectively sensitizing the host's immune cells to specific allergens (Source: UniProt P12319). When the major cat allergen, Fel d 1, enters the system, it cross-links these receptor-bound IgE molecules, initiating an intracellular signaling cascade that results in the rapid release of inflammatory mediators such as histamine and leukotrienes (Source: Journal of Allergy and Clinical Immunology, 2016). This degranulation process causes the clinical manifestations of allergy, including rhinoconjunctivitis and asthma. Therapeutic interventions like Omalizumab target this pathway by sequestering free IgE, thereby preventing the formation of the IgE-FcεRI complex (Source: StatPearls, Omalizumab). Additionally, novel monoclonal antibodies like REGN1908 and REGN1909 are designed to bind Fel d 1 directly, preventing it from cross-linking the IgE already present on the receptor surface (Source: Regeneron Pharmaceuticals).

Other names

FCER1High-affinity IgE receptorFceRIIgE-FcεRI complexFc epsilon RI

Inhibition of IgE binding to the high-affinity receptor or prevention of allergen-induced receptor cross-linking.