A bispecific antibody is a monoclonal antibodies which is designed to bind to two different antigens.One benefit of this approach is that it is possible for such an antibody to simultaneously bind to a cytotoxic cell (using a receptor like CD3) and a target cell (like CD19.)
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An antibody developed in the laboratory to recognize more than one protein on the surface of different cells. Examples include bispecific antibodies 2B1, 520C9xH22, mDX-H210, and MDX447.