高致病性禽流感病毒H5N1中和抗体的单链抗体构建与活性鉴定

Preparation and Identification of a Single-chain Antibody Fragment Against High Pathogenic H5N1 Avian Influenza Virus

在本实验室研制出的多株针对H5N1血凝素的鼠单抗中,10F7对34株H5N1病毒株都有血凝抑制和中和活性,具有特异性高、反应性强、识别谱广的特点。通过基因工程构建10F7单链抗体(scFv)表达重组质粒,在大肠杆菌中表达并纯化scFv,经血凝抑制实验及中和实验检测其活性。结果在针对3株病毒的血凝抑制实验中,10F7scFv蛋白对其中2株H5N1病毒均显示出结合活性,而对H9毒株没有反应。在针对7株H5N1病毒的中和实验中,10F7scFv对5株病毒具有较好的中和能力。H5N1广谱中和抗体10F7的单链抗体构建,为进一步研制针对H5N1禽流感病毒的治疗性抗体奠定了基础。

Previously, an mAb 10F7 was developed against H5N1 hemagglutinin, which was highly specific to 34 different H5N1 strains and showed good neutralizing activity. In the present study, the single-chain fragment of the antibody was cloned into a prokaryotic vector and then expressed in E. coli. The activity of the scFv was tested in hemagglution inhibition and neutralization experiment. Two H5N1 virus strains were inhibited to bind erythrocyte cells by the scFv while the H9 virus was not. Also, five H5N1 virus strains were neutralized during infecting MDCK cells. These results showed an approachable method for developing therapeutic antibody to H5N1 virus.