非特异性抗体80R的改造对SARS-CoV-2识别增强的研究

CDRH3 modifications improve the recognition of nonspecific antibody 80R against SARS-CoV-2

目的利用抗体工程技术快速获得严重急性呼吸综合征冠状病毒2(severe acute respiratory syndrome coronavirus 2,SARS-CoV-2)的识别抗体。方法针对SARS-CoV抗体80R,因其不能很好地识别SARS-CoV-2-S蛋白,通过不同长度氨基酸重复和延伸等策略对80R的重链功能区进行了突变改造。结果改造共获得了12个突变抗体,通过ELISA检测表达的抗体,发现Mu8对SARS-CoV-2的S蛋白识别增强,微量热泳动检测显示Mu8具备了相应的抗体亲和力,K_(d)为(7.29±2.34)μmol/L。结论获得的突变抗体Mu8能够识别、结合SARS-CoV-2的S抗原,该策略为新发病原体识别抗体的快速制备提供了一种可行思路。

Objective Quick preparation of the specific antibody of SARS-CoV-2 by antibody engineering for rapid identification and diagnosis for the pathogen is critical for the prevention and treatment of SARS-CoV-2.Methods In this study,with the purpose to obtain specific antibody against SARS-CoV-2,we modified the existing non-specific parental antibodies,SARS-CoV antibody 80 R,which cannot recognize the S protein of SARS-CoV-2,and reconstructed the heavy chain of 80 R by amino acids extension with different lengths.Results Totally,12 antibody mutants were obtained by amino acids mutation.The mutant antibody Mu8 exhibited better recognition with the S spike protein of SARS-CoV-2 by ELISA and improved affinity with K_(d) at(7.29±2.34)μmol/L by microscale thermophoresis.Conclusion The study provided a feasible strategy for the rapid preparation of specific antibodies for the identification of emerging pathogens.