Purified anti-human FcepsilonRIalpha

High affinity IgE receptor (FcepsilonRI) plays a key role in IgE-mediated allergic immune response. FcepsilonRI is a tetrameric receptor complex, which is composed of one alpha-subunit (FcepsilonRIalpha), one beta-subunit, and two gamma-subunits. FcepsilonRIalpha directlybinds IgE with high affinity, while the beta- and gamma-chains are responsible for mediatingintracellular signals. FcepsilonRIalpha is a 50 kD transmembrane protein with Ig superfamily structure. It is primarily found on mast cells and basophils. Further studies have indicated that FcepsilonRIalpha is also expressed on many inflammatory cells including cutaneuos Langerhans cells, dendritic cells, monocytes of patients with allergic disorders, platelets, bronchial epithelial cells, eosinophils produced in hypereosinophilic syndrome, and neutrophils from allergy-induced asthma patients.