Shrikant V. Deshpande

Effect of different linkages between chelates and monoclonal antibodies on levels of radioactivity in the liver

After injection of radiometal labeled antibodies, the radionuclide accumulates in the liver. This might be altered by a metabolizable linkage between metal chelate and antibody. Four benzyl-EDTA chelating agents were synthesized and conjugated to mouse monoclonal antibody Lym-1. Liver uptake of 111In in nontumored mice 72 h after injection was 2.2, 13.4, 7.6 and 20% for disulfide, thioether, thiourea or peptide linkages, respectively. 111In excreted in the urine was still in the benzyl-EDTA chelate form, as shown by binding to a specific anti-chelate antibody.

The Design of a Radiolabeled Monoclonal Antibody for Radioimmunodiagnosis and Radioimmunotherapy

Monoclonal antibodies have become recognized as promising carrier molecules for the development of target specific radiopharmaceuticals. Since the hybridoma technology can be used to discriminate small epitopes on products of either normal or abnormal cells and to produce antibodies which react uniquely with those epitopes, a new generation of biologic targets are being sought on hormones, hormone precursors, myosin, fibrin, blood cells, infectious agents, tumor cells, tumor associated antigen products and so forth. Although critical for ultimate imaging and therapeutic success, epitope recognition and appropriate target selection is only the first step toward immunologically derived radiopharmaceuticals.