Anti-IgE Antibody Therapy

The defining feature of immediate hypersensitivity reactions is the presence of antigen-specific IgE antibodies. In the classic description of the reaction, the IgE is bound to tissue mast cells and reexposure to antigen triggers these cells to secrete a variety of mediators. Therapeutic targets to ameliorate the disease include everything from the immune response responsible for IgE generation to the end-organ response to secreted mediators. For any therapeutic approach that seeks to reduce circulating IgE levels, it is necessary to consider the sensitivity of the system to antigenic stimulation. There remain many unknown influences on the patient’s response to antigenic exposure, but there is enough quantitative information concerning one aspect of the IgE-mediated reaction to make some predictions about therapeutic requirements. For any therapeutic approach that seeks to decrease free IgE antibody levels in serum and tissue, there will be concerns that relate to the speculated protective effects of IgE antibody.