title: An improved method of direct labeling monoclonal antibodies with 99mTc.
abstract: An improved method of direct labeling MAbs with 99mTc is described. Two murine monoclonal antibodies, designated Lym-1 and B72.3, have been successfully labeled with 99mTc in 0.1 M borate buffer at pH 9.3. The choice of buffer and pH was essential for obtaining a radiolabeling yield greater than or equal to 98%. In vitro studies demonstrated that the radiolabeled antibodies were stable and retained their immunoreactivity. Imaging and biodistribution studies using Raji and LS174T human tumor-bearing nude mice demonstrated a significant tumor uptake at 24-h post-injection of 99mTc-labeled MAbs. This improved labeling method showed better stability than those of previously published methods and resulted in significant improvement in the uptake of antibody in tumor. External images at 24 h post-injection revealed clearly visible tumors demonstrating the benefit of this method for tumor immunoscintigraphy.
authors.affiliation: Department of Pathology, University of Southern California, School of Medicine, Los Angeles 90033.
authors.forename: M M
authors.initials: MM
authors.lastname: Alauddin
authors.forename: L A
authors.initials: LA
authors.lastname: Khawli
authors.forename: A L
authors.initials: AL
authors.lastname: Epstein
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D002051:Burkitt Lymphoma / Q000000981:diagnostic imaging; D002851:Chromatography, High Pressure Liquid; D002854:Chromatography, Paper; D005260:Female; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D015609:Organotechnetium Compounds / Q000737:chemistry / Q000493:pharmacokinetics; D004369:Pentetic Acid; D016719:Radioimmunodetection; D012709:Serum Albumin; D014018:Tissue Distribution
chemical_list: D000911:Antibodies, Monoclonal; D015609:Organotechnetium Compounds; D012709:Serum Albumin; D004369:Pentetic Acid