乙肝病毒核心蛋白人源单链抗体在大肠杆菌中的表达

Expression of soluble human single chain Fv antibody to hepatitis B core antigen in E.coli

目的获得可溶性的抗乙型肝炎病毒（HBV）核心蛋白（core ）的人源单链可变区抗体（ScFv），为得到纯度高、活力强的HBc-ScFv和进一步的抗HBV 治 疗奠定基础。方法采用噬菌体表面展示技术，以重组的HBV核心蛋白为包 被抗原，从噬菌体单链可变区抗体库中经过5轮“吸附-洗脱-扩增”筛选过程，获得抗原 结 合活性较强的乙型肝炎核心蛋白人源单链可变区抗体ScFv 片段克隆，并对其进行DNA序列及 免疫活性测定。从噬菌体抗体阳性克隆中提取质粒转化大肠杆菌HB2151，IPTG诱导表达乙型 肝炎核心蛋白可溶性人源单链可变区抗体，ELISA和western blot检测其抗原结合特异性。 结果克隆了乙型肝炎核心蛋白的单链可变区抗体基因；经DNA酶切和序列 分析表明，该抗体基因由771个碱基组成；ELISA 和western blot结果表明：在大肠杆菌HB2 151中经IPTG诱导表达的可溶性乙型肝炎核心蛋白的单链可变区抗体，具有结合乙型肝炎核 心蛋白的特异性和免疫活性。结论克隆、鉴定并在大肠杆菌HB2151中表 达了可溶性的HBc-ScFv。

Objective Expression of human single chain Fv antibody to hepatitis B core protein in E. coli. Methods The phage antibody library was panned by HBc antigen which was coated in a micro-titer plate, after five rounds of bio-panning, 60 clones were identified specific to HBc antigen. The specificity of ScFv was determined by ELISA. E.coli HB2151 were transformed and induced by IPTG. The specificity of ScFv was evaluated by ELISA and western blot hybridization. ResultsHBc-ScFv DNA digestion and sequence data showed that the ScFv gene is composed of 771 bp. ELISA and western blot demonstrated that the soluble human single chain Fv antibody to hepatitis B virus core antigen has a specific combination character with hepatitis B virus core ant igen. Conclusion Identification and expression of HBc antigen specific ScFv from E.coli were successfully achieved.