Construction and Preclinical Evaluation of 124 I/ 125 I-Labeled Antibody Targeting T Cell Immunoglobulin and Mucin Domain-3

作者：Jinping Tao, Ziqing Zeng, Chengxue He, Meng Lin, Wenyuan Zhou, Yanan Ren, Xiaopan Ma, Zilei Wang, Jiayue Liu, Dapeng Li, Qian Zhang, Chuanke Zhao, Zhi Yang, Hua Zhu · 发表于：Molecular Pharmaceutics · 年份：2024 · DOI：10.1021/acs.molpharmaceut.3c01046 · 被引用次数：11 · 研究领域：Galectins and Cancer Biology、CAR-T cell therapy research、Cancer Immunotherapy and Biomarkers

T cell immunoglobulin and mucin domain-3 (TIM3; HAVCR2) is a transmembrane protein that exerts negative regulatory control over T cell responses. Studies have demonstrated an upregulation of TIM3 expression in tumor-infiltrating lymphocytes (TILs) in cancer patients. In this investigation, a series of monoclonal antibodies targeting TIM3 were produced by hybridoma technology. Among them, C23 exhibited favorable biological properties. To enable specific binding, we developed a 124 I/ 125 I-C23 radio-tracer via N -bromosuccinimide (NBS)-mediated labeling of the monoclonal antibody C23. Binding affinity and specificity were assessed using the 293T-TIM3 cell line, which overexpresses TIM3, and the parent 293T cells. Furthermore, biodistribution and in vivo imaging of 124 I/ 125 I-C23 were examined in HEK293TIM3 xenograft models and allograft models of 4T1 (mouse breast cancer cells) and CT26 (mouse colon cancer cells). Micro-PET/CT imaging was conducted at intervals of 4, 24, 48, 72, and/or 96 h post intravenous administration of 3.7–7.4 MBq 124 I-C23 in the respective model mice. Additionally, immunohistochemistry (IHC) staining of TIM3 expression in dissected tumor organs was performed, along with an assessment of the corresponding expression of Programmed Death 1 (PD1), CD3, and CD8 in the tumors. The C23 monoclonal antibody (mAb) specifically binds to TIM3 protein with a dissociation constant of 23.28 nM. The 124 I-C23 and 125 I-C23 radio-tracer were successfully prepared wit...