Radiometal Labeling of Antibodies and Antibody Fragments for Imaging and Therapy

Monoclonal antibodies (MAbs) are highly selective agents for delivering radiation to tumors both for in vivo imaging (radioimmunoscintigraphy, RIS) and for therapy (radioimmunotherapy, RIT). Antibody-based radiopharmaceuticals can be labeled with iodine nuclides (123 I for imaging, 131 I for therapy) or with metallic nuclides such as the γ radiation-emitting nuclides 111 In and 199m Tc for imaging or the β′ particle-emitting nuclides 90 Y, 67 Cu, and 188/186 Re for therapy. The labeling of antibodies with three metallic nuclides is described here: 67 Cu for both imaging and therapy, 99m Tc for imaging, and 188/186 Re for therapy.