Xiang Xinchu, Liu Xue, Hu Yaokai, Zhao Chengjun, Luo Wenxin
State key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China.
Sheng Wu Gong Cheng Xue Bao. 2020 Dec 25;36(12):2860-2867. doi: 10.13345/j.cjb.200180.
Glypican-3 (GPC3) is a key member of Glypican family and plays an important role in the development, angiogenesis and metastasis of hepatocellular carcinoma (HCC). Most HCC overexpresses GPC3, but GPC3 is hardly detected in normal adult liver and benign liver lesions, so it is regarded as a highly specific diagnostic marker and an ideal therapeutic target for HCC. In this study, we cloned the heavy and light chain variable region gene from the monoclonal antibody targeted to GPC3 screened in the previous stage, and linked it with a segment of flexible peptide (Linker) to obtain the single chain antibody against GPC3. The single chain antibody gene was cloned into vector for prokaryotic expression and purified to obtain high purity protein. Detection shows that the single-chain antibody produced by us has the same binding activity with the full-length antibody, and can accurately target the tumor site of Huh7 tumor-bearing model mice after coupling Cy5.5 fluorescence, suggesting that the single-chain antibody has the potential to realize multi-directional liver cancer precise surgical navigation under the guidance of a probe.
磷脂酰肌醇蛋白聚糖-3(GPC3)是磷脂酰肌醇蛋白聚糖家族的关键成员,在肝细胞癌(HCC)的发生发展、血管生成和转移中发挥重要作用。大多数肝癌细胞中GPC3呈过表达,但在正常成人肝脏和良性肝病变中几乎检测不到,因此它被视为一种高度特异性的诊断标志物以及肝癌的理想治疗靶点。在本研究中,我们从前期筛选出的靶向GPC3的单克隆抗体中克隆出重链和轻链可变区基因,并将其与一段柔性肽(Linker)连接,从而获得抗GPC3单链抗体。将单链抗体基因克隆到载体中进行原核表达并纯化,以获得高纯度蛋白。检测表明,我们制备的单链抗体与全长抗体具有相同的结合活性,并且在偶联Cy5.5荧光后能够准确靶向荷Huh7瘤模型小鼠的肿瘤部位,这表明该单链抗体具有在探针引导下实现多方位肝癌精准手术导航的潜力。