A Tri-Specific Binding Molecules are multi-chain polypeptide molecules that possess three Binding Domains and are thus capable of mediating coordinated binding to three epitopes. The Tri-Specific Binding Molecule can possess binding domains that permit it to immunospecifically bind to: (1) an epitope of a first Cancer Antigen, (2) an epitope of a second Cancer Antigen, and (3) an epitope of a molecule that is expressed on the surface of an immune system effector cell, and are thus capable of localizing an immune system effector cell to a cell that expresses a Cancer Antigen, so as to thereby facilitate the killing of such cancer cell.一種三特異性結合分子具有三個結合結構域的多鏈多肽分子，因此能夠介導與三個表位的協同結合。三特異性結合分子可具備允許其免疫特異性結合以下表位元的結合結構域：(1) 第一癌症抗原的表位、(2) 第二癌症抗原的表位和(3) 在免疫系統效應細胞的表面上表達的分子的表位，因此能夠將免疫系統效應細胞定位至表達癌症抗原的細胞，以便從而利於殺傷癌症細胞。
