Experimental therapy of disseminated B-Cell lymphoma xenografts with 213Bi-labeled anti-CD74.
A (213)Bi-labeled antibody to CD74 was evaluated as a therapeutic agent for B-cell lymphoma. The alpha-particle emission, with a half-life of 46 min, is appropriate for therapy of micrometastases. The labeled Ab retained full immunoreactivity, and was potent at single-cell kill of the Raji B-lymphoma cell line. Approximately 30 decays of cell-bound (213)Bi was required for a cell kill of 99%, and dosimetry calculations suggested that the cGy dose delivered was sufficient to produce the level of toxicity observed. A non-reactive control Ab, labeled similarly, also produced toxicity, due to decays occurring in the medium, but was approximately 3-fold less potent than the reactive Ab. In a SCID mouse xenograft micrometastatic model, Ab injection at day 2 or day 5 after tumor inoculation resulted in strong, specific suppression of tumor growth, with some apparent cures.
D000818:Animals; D000906:Antibodies / Q000276:immunology / Q000627:therapeutic use*; D000944:Antigens, Differentiation, B-Lymphocyte / Q000276:immunology / Q000627:therapeutic use; D001729:Bismuth / Q000627:therapeutic use*; D045744:Cell Line, Tumor / Q000166:cytology / Q000473:pathology; D002470:Cell Survival / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D000949:Histocompatibility Antigens Class II / Q000276:immunology / Q000627:therapeutic use; D016393:Lymphoma, B-Cell / Q000276:immunology / Q000473:pathology / Q000532:radiotherapy*; D051379:Mice; D016513:Mice, SCID; D016499:Radioimmunotherapy / Q000379:methods*; D011868:Radioisotopes / Q000627:therapeutic use*; D019275:Radiopharmaceuticals; D011879:Radiotherapy Dosage; D013534:Survival; D016378:Tissue Transplantation; D014183:Transplantation, Heterologous; D016896:Treatment Outcome
D000906:Antibodies; D000944:Antigens, Differentiation, B-Lymphocyte; D000949:Histocompatibility Antigens Class II; D011868:Radioisotopes; D019275:Radiopharmaceuticals; C045084:invariant chain; D001729:Bismuth