This invention relates to reconstructed polypeptides which have properties of inducing apoptosis of nucleated blood cells having Integrin Associated Protein (IAP) and causing no hemagglutination. The reconstructed polypeptides comprise two or more H chain V regions and two or more L chain V regions of a monoclonal antibody which induces apoptosis of nucleated blood cells having IAP. The reconstructed polypeptides are useful as a therapeutic agent for blood dyscrasia such as leukemia.