radioiodinated anti-carcinoembryonic antigen diabody

Radioiodinated anti-carcinoembryonic antigen (anti-CEA) diabody is a radiolabeled biologic imaging agent designed for the detection of CEA-expressing carcinomas. It consists of a diabody—a noncovalent dimer of single-chain variable fragments (scFv) with a molecular weight of approximately 55 kDa—derived from the T84.66 monoclonal antibody. The diabody is labeled with radioiodine isotopes (such as 123I, 124I, or 131I) for use in radioimmunoscintigraphy or positron emission tomography (PET). By targeting CEA, a cell-surface glycoprotein overexpressed in colorectal, lung, pancreatic, and other cancers, the agent enables high-contrast imaging due to its rapid tumor localization and fast systemic clearance compared to intact antibodies. It was primarily developed by researchers at the City of Hope National Medical Center.

Other names

radioiodinated anti-CEA diabody124I-anti-CEA diabody123I-anti-CEA diabody131I-anti-CEA diabodyradioiodinated T84.66 diabody