| Popis: |
The utility of radiolabeled monoclonal antibodies (Mabs) and Mab fragments in the radioimmunodetection (RAID) of cancer has been established with 131I, 111In, and 123I [1–9]. More recently, however, increasing efforts have been expended to label these reagents with 99mTc. Indeed, successful clinical application of commercial monoclonal antibody imaging products will probably be dependent on the development of simple, inexpensive methods to label antibody or antibody fragments with this radionuclide. When compared with other radionuclides used to label Mabs, 99mTc has the following advantages: low cost, ready availability, ideal nuclear properties for gamma cameras, and reduced patient radiation exposure per millicurie of radionuclide administered. Strategies employed by different investigators to label antibodies and antibody fragments with 99mTc fall into two major categories. In one approach, efforts have been made to use a ligand to attach 99mTc indirectly to the antibody. The second approach has been to bind the radionuclide directly to intrinsic receptor sites or to altered groups of the protein backbone of the antibody molecule. |
