title: Direct 99m Tc labeling of Herceptin (trastuzumab) by 99m Tc(I) tricarbonyl ion.
abstract: By simply incubating Herceptin (trastuzumab) with [99m Tc(CO)3(OH2)3]+ ion in saline, a significant yield of 99m Tc-labeled trastuzumab was found to be achievable. The effective labeling may be based on that trastuzumab is inherent with endogenous histidine group to which 99m Tc(I) tricarbonyl ion can be strongly bound. For practical 99m Tc labeling processing, trastuzumab was purified beforehand from the commercial product, Herceptin (Genentech) via size exclusion chromatography to remove the excipient, alpha-histidine and a high-labeled yield could be obtained by incubating the purified trastuzumab with [99m Tc(CO)3(OH2)3]+. Retention of bioactivity of the 99m Tc(I)-labeled trastuzumab was validated using a cell binding test.
authors.affiliation: Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan.
authors.forename: Wan-Jou
authors.initials: WJ
authors.lastname: Chen
authors.forename: Chao-Liang
authors.initials: CL
authors.lastname: Yen
authors.forename: Su-Tang
authors.initials: ST
authors.lastname: Lo
authors.forename: Kuo-Ting
authors.initials: KT
authors.lastname: Chen
authors.forename: Jem-Mau
authors.initials: JM
authors.lastname: Lo
mesh_terms: D000911:Antibodies, Monoclonal / Q000737:chemistry* / Q000493:pharmacokinetics / Q000502:physiology; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology; D001667:Binding, Competitive; D001943:Breast Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000532:radiotherapy; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D007553:Isotope Labeling / Q000379:methods; D019275:Radiopharmaceuticals / Q000138:chemical synthesis* / Q000493:pharmacokinetics / Q000494:pharmacology; D013667:Technetium / Q000737:chemistry*; D017556:Technetium Compounds / Q000138:chemical synthesis* / Q000493:pharmacokinetics / Q000494:pharmacology; D000068878:Trastuzumab
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D019275:Radiopharmaceuticals; D017556:Technetium Compounds; D013667:Technetium; D000068878:Trastuzumab