抗A型肉毒毒素人源单链抗体融合蛋白的重组设计

Recombinant Design of Fc Fusion Protein of Human ScFv Against BoNTa

以获得的抗A型肉毒毒素单链抗体为模板,进行融合改构,将人IgG1的Fc片段连接到ScFv的C端,在大肠杆菌中实现抗体融合蛋白ScFv-Fc的表达,表达量30%以上,蛋白以包含体形式存在,经过体外变复性的抗体融合蛋白ScFv-Fc,进行Protein G Sepharose柱亲和层析纯化,纯度达90%～95%.体外活性检测结果表明,重组抗体融合蛋白ScFv-Fc可以特异结合A型肉毒类毒素抗原,其相对亲和力近似于母本单链抗体,其稳定性高于母本单链抗体.

Human ScFv against botulinum neurotoxin serotype A （BoNTa） was modified by fusing human IgGl Fc to C terminal of ScFv. ScFv-Fc fusion protein was expressed at high level over 30% of total host cell proteins in E. coli Recombinant protein existed in inclusion body form. Renatured ScFv-Fc was purified to 90% - 95% by Protein G Sepharose column. In vitro ScFv-Fc could bind specific to toxiod BoNTa in ELISA. Recombinant ScFv-Fc had similar relative affinity to parent ScFv and had improved stability.