Jin Qiu, Yao Zhangyu, Liu Fangzhou, Di Yaxuan, Gao Jun, Zhang Xiao
Key Laboratory of Antibody Technology, National Health Commission, Nanjing Medical University, Nanjing, Jiangsu, China.
Department of Basic Medicine, Jiangsu College of Nursing, Huai`an, Jiangsu, China.
Hum Vaccin Immunother. 2022 Dec 31;18(1):2035118. doi: 10.1080/21645515.2022.2035118. Epub 2022 Mar 3.
The highly pathogenic avian influenza H5N1 virus poses a serious threat to humans. Due to its antiviral activity, antibody-based therapy is one of the possible effective countermeasures. Here, a combination of intracellular and extracellular human antibodies was investigated and showed an improved protective effect.
The scFv4F5-based intracellular antibody vectors and IgG1 extracellular antibody were constructed and expressed, respectively, and the sensitivity, specificity, and affinity of these antibodies were determined in vitro. In vivo, the protective effect of IgG1 and the combination of antibodies were tested respectively. Furthermore, the dynamics of viral replication, the related cytokines and apoptosis-related proteins were detected.
In vitro, the expressed intracellular antibody inhibited H5N1 virus propagation and the IgG1 exhibited high specificity, sensitivity, and affinity against the H5N1 virus. In vivo, the extracellular antibody could inhibit viral propagation in a dose-dependent manner. The protective effect of IgG1 was good in a mouse model, and the survival was 100% at a dose of 15 mg/kg under infection with 100 TCID virus. When the intracellular antibody was pre-transfected in combination with IgG1, it had a better protective effect. The survival was 16.67% under treatment with IgG1 alone and up to 83.33% under treatment with the combination of antibodies when challenge of 500 TCID virus. Furthermore, the levels of cytokines IFN-γ, IL-6, IL-10 and some apoptosis-related proteins increased.
This antibody combination technique could be used as an appropriate and powerful alternative to antiviral therapy.
高致病性禽流感H5N1病毒对人类构成严重威胁。基于其抗病毒活性，基于抗体的疗法是可能有效的对策之一。在此，研究了细胞内和细胞外人类抗体的组合，并显示出改善的保护作用。
分别构建并表达基于单链抗体片段4F5的细胞内抗体载体和IgG1细胞外抗体，并在体外测定这些抗体的敏感性、特异性和亲和力。在体内，分别测试了IgG1和抗体组合的保护作用。此外，检测了病毒复制的动态、相关细胞因子和凋亡相关蛋白。
在体外，表达的细胞内抗体抑制H5N1病毒的传播，IgG1对H5N1病毒表现出高特异性、敏感性和亲和力。在体内，细胞外抗体可以剂量依赖性方式抑制病毒传播。IgG1在小鼠模型中的保护作用良好，在感染100个半数组织培养感染剂量病毒时，15mg/kg剂量下的存活率为100%。当细胞内抗体与IgG1联合预先转染时，具有更好的保护作用。在500个半数组织培养感染剂量病毒攻击时，单独使用IgG1治疗的存活率为16.67%，联合抗体治疗时高达83.33%。此外，细胞因子IFN-γ、IL-6、IL-10的水平和一些凋亡相关蛋白增加。
这种抗体组合技术可作为抗病毒治疗的一种合适且有效的替代方法。
