skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Bismuth-212-labeled anti-Tac monoclonal antibody: alpha-particle-emitting radionuclides as modalities for radioimmunotherapy

Journal Article · · Proc. Natl. Acad. Sci. U.S.A.; (United States)

Anti-Tac, a monoclonal antibody directed to the human interleukin 2 (IL-2) receptor, has been successfully conjugated to the alpha-particle-emitting radionuclide bismuth-212 by use of a bifunctional ligand, the isobutylcarboxycarbonic anhydride of diethylenetriaminepentaacetic acid. The physical properties of 212Bi are appropriate for radioimmunotherapy in that it has a short half-life, deposits its high energy over a short distance, and can be obtained in large quantities from a radium generator. Antibody specific activities of 1-40 microCi/microgram (1 Ci = 37 GBq) were achieved. Specificity of the 212Bi-labeled anti-Tac was demonstrated for the IL-2 receptor-positive adult T-cell leukemia line HUT-102B2 by protein synthesis inhibition and clonogenic assays. Activity levels of 0.5 microCi or the equivalent of 12 rad/ml of alpha radiation targeted by anti-Tac eliminated greater than 98% the proliferative capabilities of HUT-102B2 cells with more modest effects on IL-2 receptor-negative cell lines. Specific cytotoxicity was blocked by excess unlabeled anti-Tac but not by human IgG. In addition, an irrelevant control monoclonal antibody of the same isotype labeled with 212Bi was unable to target alpha radiation to cell lines. Therefore, 212Bi-labeled anti-Tac is a potentially effective and specific immunocytotoxic reagent for the elimination of IL-2 receptor-positive cells. These experiments thus provide the scientific basis for use of alpha-particle-emitting radionuclides in immunotherapy.

Research Organization:
National Cancer Institute, Bethesda, MD
OSTI ID:
5802195
Journal Information:
Proc. Natl. Acad. Sci. U.S.A.; (United States), Vol. 2
Country of Publication:
United States
Language:
English

Similar Records

Radioimmunotherapy of peritoneal human colon cancer xenografts with site-specifically modified sup 212 Bi-labeled antibody
Journal Article · Thu Feb 01 00:00:00 EST 1990 · Cancer Research; (USA) · OSTI ID:5802195

The multichain interleukin 2 receptor: A target for immunotherapy in lymphoma, autoimmune disorders, and organ allografts
Journal Article · Fri Jan 12 00:00:00 EST 1990 · JAMA, Journal of the American Medical Association; (USA) · OSTI ID:5802195

Alpha particle radioimmunotherapy: Animal models and clinical prospects
Journal Article · Thu Jun 01 00:00:00 EDT 1989 · International Journal of Radiation Oncology, Biology and Physics; (USA) · OSTI ID:5802195