immunoglobulin complex IgE immunoglobulin complex Note that an IgE immunoglobulin complex has the function of antigen binding if a suitable antigen is available. GO:0071742 cellular_component 2010-03-24T01:44:53Z A protein complex composed of two identical immunoglobulin heavy chains of the IgE isotype and two identical immunoglobulin light chains, held together by disulfide bonds. An IgE immunoglobulin complex may be embedded in the plasma membrane or present in the extracellular space, in mucosal areas or other tissues, or circulating in the blood or lymph.