Izard M E, Boniface G R, Hardiman K L, Brechbiel M W, Gansow O A, Walkers K Z
Biomedicine and Health Program, ANSTO, Lucas Heights, New South Wales, Australia.
Bioconjug Chem. 1992 Jul-Aug;3(4):346-50. doi: 10.1021/bc00016a015.
Samarium-153 (153Sm) radioimmunoconjugates of the monoclonal antibody K-1-21 were produced using the bifunctional chelate 2-(p-isothiocyanatobenzyl)-6- methyldiethylenetriaminepentaacetic acid (Mx-DTPA). The specific activity (up to 150 MBq mg-1) and percent retained immunoreactivity (greater than 75%) were similar to that of 153Sm-K-1-21 conjugates formed with cyclic DTPA anhydride (cDTPAa). In vivo biodistribution studies showed specific localization of 153Sm-Mx-DTPA-K-1-21 to target antigen implants and higher blood pool and lower uptake in liver, spleen, kidney, and bone when compared to 153Sm-cDTPAa-K-1-21. The improved in vivo distribution of 153Sm-Mx-DTPA-K-1-21 should result in lower radiotoxicity to nontarget tissues when used for radioimmunotherapy purposes.
使用双功能螯合剂2-(对异硫氰酸苄基)-6-甲基二乙三胺五乙酸（Mx-DTPA）制备了单克隆抗体K-1-21的钐-153（¹⁵³Sm）放射免疫缀合物。其比活度（高达150 MBq mg⁻¹）和保留的免疫反应性百分比（大于75%）与用环二乙三胺五乙酸酐（cDTPAa）形成的¹⁵³Sm-K-1-21缀合物相似。体内生物分布研究表明，与¹⁵³Sm-cDTPAa-K-1-21相比，¹⁵³Sm-Mx-DTPA-K-1-21可特异性定位于靶抗原植入物，且血池较高，在肝脏、脾脏、肾脏和骨骼中的摄取较低。¹⁵³Sm-Mx-DTPA-K-1-21体内分布的改善，在用于放射免疫治疗时，应会降低对非靶组织的放射毒性。
