The Receptor with High Affinity for Immunoglobulin E

This review is about one of the physiologically important macromolecules that interact with the Fc domains of immunoglobulins. Such substances (complement, "immunoglobulin binding factors," Fc receptors) can convert the simple binding of antigen to antibody into a biologically meaningful event. The protein reviewed--the Fc receptor with high affinity for monomeric immunoglobulin E (IgE)--is only one of several proteins that interact with IgE. In addition to high affinity, its special characteristic is its distribution on the plasma membrane of mast cells and basophils exclusively. Activation of this receptor initiates release of preformed mediators contained in intracellular granules and the biosynthesis of a variety of biologically active lipids such as the leukotrienes.