IgE (Immunoglobulin E) is one of five immunoglobulins (IgM, IgG, IgD, IgA and IgE). It is the final product of the immunoglobulin family to be discovered. IgE not only has a unique chemical structure but also has many important physiological functions such as type I hypersensitivity reactions, parasitic infections, autoimmune processes, and is indispensable in the pathogenesis of allergic disorders.