化学学报 ›› 2015, Vol. 73 ›› Issue (1): 36-40.DOI: 10.6023/A14120832 上一篇    下一篇

研究论文

111In-DOTA-mAb109单克隆抗体探针的制备及其分子显像的研究

朱华a, 李囡a, 张宏b, 林新峰a, 李振甫b, 杨志a   

  1. a 北京大学肿瘤医院暨北京市肿瘤防治研究所 核医学科 恶性肿瘤发病机制及转化研究教育部重点实验室 阜成路52号 100142;
    b 北京大学肿瘤医院暨北京市肿瘤防治研究所 中心实验室 恶性肿瘤发病机制及转化研究教育部重点实验室 阜成路52号 100142
  • 收稿日期:2014-12-02 出版日期:2015-01-14 发布日期:2014-12-11
  • 通讯作者: 杨志 E-mail:pekyz@163.com
  • 基金资助:

    项目受国家自然科学基金(Nos. 81172083, 81371592, 81401467), 北京自然科学基金(Nos. 7132040, 81401467), 北京大学医学-工学联合研究种子基金(2014医-工-12)资助.

Synthesis and Evaluation of 111In-DOTA-mAb109 Monoclonal Antibody for Potential SPECT Molecular Imaging

Zhu Huaa, Li Nana, Zhang Hongb, Lin Xinfenga, Li Zhenfub, Yang Zhia   

  1. a Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Nuclear Medicine, Peking University Cancer Hospital & Institute, Beijing 100142;
    b Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Central Laboratory, Peking University Cancer Hospital & Institute, Beijing 100142
  • Received:2014-12-02 Online:2015-01-14 Published:2014-12-11
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 81172083, 81371592, 81401467) & Beijing Natural Science Foundation (Nos. 7132040, 81401467), the Seeding Grant for Medicine and Engineering Sciences of Peking University (2014-ME-12).

以具有肿瘤靶向的新型单克隆抗体mAb109, 借助其表面的氨基偶联双功能螯合剂获得可用于放射标记的DOTA-mAb109, 制备了111In-DOTA-mAb109分子探针. Radio-HPLC分析结果表明, 其标记率96%, 放化纯度大于98%. 体外稳定性实验结果表明111In-DOTA-mAb109在NaAc、PBS缓冲溶液以及5%人血清白蛋白溶液中均具有很高的稳定性. 建立 PANC-1胰腺癌裸鼠模型, 通过Nano-SPECT设备观察其在模型动物体内的代谢情况: 在静脉注射18.5 MBq 111In-DOTA-mAb109探针分别于24 h, 48 h, 72 h进行SPECT/CT的显像, 随着时间的延长, 其在肿瘤组织表现出代谢摄取的增高. 通过断层显像, 进一步分析, 可见从特点层面观察到肿瘤组织具有明显的放射性摄取. 上述研究结果表明, 111In-DOTA-mAb109分子探针有望发展成为一种具有肿瘤靶向性的新型分子探针.

关键词: mAb109分子探针, 肿瘤靶向, 单光子发射断层显像, 铟-111

Peroxiredoxin-I is a protein encoded by the Peroxiredoxin I gene, which highly expressed in many tumor tissues, such as lung cancer, breast cancer, rectal cancer, stomach cancer. Peroxiredoxin-I has a proliferative effect and plays a role in cancer development, recurrence or progression. The mAb 109 antibody can specific binding to Peroxiredoxin-I protein. We recently reported the synthesis 99mTc-labeled mAb109 for Single-photon emission computed tomography (SPECT) imaging. Those studies have showed that 99mTc-mAb 109 still preserved its biological functions and specifically binding to the target tumors. The aim of this research was to develop new radionuclide labeled mAb109 antibody for prolonged tumor targeted molecular imaging. In this paper, the precursor compound 2-(4-isothiocyanatobenzyl)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-mAb 109 (DOTA-mAb109) was synthesized for potential radioactive imaging agents. Then, a radioisotope indium-111 (t1/2=67.3 h) was labeling to DOTA-mAb109 for further radio-biological evaluation. The DOTA is chelated to the 111In3+ center through four nitrogens and four carboxylate oxygens, resulting in an eight-coordinate complex. The labeling efficiency of 111In-DOTA-mAb109 was tested by Radio-TLC/HPLC. The radiolabeling yield was over 96%, the radio chemical purity was over 99% by PD-10 column purification. The in vitro stability tests were presented in 5% Human serum albumin (HSA) for 72 h at 25 ℃. Less than 5% 111In dissociation was detected by Radio-HPLC. 111In-DOTA- mAb109 shows excellent radiochemical property. Nano-SPECT imaging of pancreatic carcinoma-1 tumor-bearing nude mice revealed that tumor uptake of 111In-DOTA-mAb109 got a gradual accumulation from 24 h, 48 h to 72 h after post-injection of 18.5 MBq radiolabeled antibody. The cardiac area was clearly seen up to 48 h post injection, reflecting a long blood circulation time for 111In-DOTA-mAb109. Uptake in the tumor was clearly visualized by emission computed tomography. These results suggest that the 111In-DOTA-mAb109 molecular probe is a promising tracer for tumor diagnosis.

Key words: mAb 109 molecular probe, tumor target, SPECT imaging, indium-111