不同表达系统来源的SARS-CoV-2 N蛋白以及联合S1蛋白的免疫效果评价  

Evaluation of immune effects of SARS-CoV-2 N proteins derived from different expression systems and combined with S1 protein

作　　者：杨燕 王慧娟[2] 单徐畅 郭晓炎 梁殷洁 祁振勇 邓瑶[2] 谭文杰[2] Yang Yan;Wang Hujuan;Shan Xuchang;Guo Xiaoyan;Liang Yinjie;Qi Zhenyong;Deng Yao;Tan Wenjie(Zhejiang Provincial Key Laboratory of Medical Genetics,Schoolof Laboratory Medicine and Life Sciences,Wenzhou Medical University,Wenzhou 325035,China;Key Laboratory of Biosafety,National Health Commission of the People's Republic of China,National Institute for Viral Disease Control and Prevention,Chinese Center for Disease Control and Prevention,Beijing 102206,China;School of Public Health,Xinxiang Medical University,Xinxiang 453003,China;School of Basic Medical Sciences,Inner Mongolia Medical University,Hohhot O10110,China;Collaborative Innovation Centre of Regenerative Medicine and Medical Bio-Resource Development and Application Co-constructed by the Province and Ministry,Guangxi Medical University,Nanning 530021,China)

机构地区：[1]温州医科大学检验医学院(生命科学学院)浙江省医学遗传学重点实验室,325035 [2]中国疾病预防控制中心病毒病预防控制所、国家卫生健康委员会生物安全重点实验室,北京102206 [3]新乡医学院公共卫生学院,453003 [4]内蒙古医科大学基础医学院,呼和浩特010110 [5]广西医科大学再生医学与医用生物资源开发应用省部共建协同创新中心,南宁530021

出　　处：《国际病毒学杂志》2024年第5期359-363,共5页International Journal of Virology

基　　金：国家重点研发计划(2022YFC2304101)。

摘　　要：目的对哺乳动物细胞真核系统来源以及大肠杆菌原核系统来源的SARS-CoV-2全长N蛋白以及联合S1蛋白在小鼠体内的免疫原性进行评价.方法将蛋白与氢氧化铝以及CpG佐剂混合后通过肌肉注射免疫小鼠,初次免疫后4 w进行加强免疫,通过ELISA和SARS-CoV-2假病毒检测结合以及中和抗体水平,通过IFN-γELISpot检测细胞免疫应答水平.结果免疫S1蛋白以及N蛋白加强免疫后均能诱导产生高滴度的IgG抗体,并且均高于初次免疫(P<0.05),且真核系统与原核系统来源的N蛋白诱导的IgG抗体滴度没有差异(P>0.05).N蛋白与S1蛋白分别联合氢氧化铝和CpG佐剂均诱导了较为平衡的Th免疫应答.假病毒中和试验结果显示S1蛋白能诱导产生中和抗体,但N蛋白无法诱导产生.从细胞免疫应答水平来看,S1蛋白以及N蛋白均能诱导IFN-γ分泌细胞的产生,真核系统来源的N蛋白相较于原核系统诱导作用更强,差异有统计学意义(P<0.05).N蛋白与S1蛋白联合免疫小鼠与仅免疫一种蛋白相比,无论是体液免疫还是细胞免疫均没有得到增强.结论本研究比较了不同表达系统来源的N蛋白以及联合N蛋白与S1蛋白的免疫原性,为进一步揭示SARS-CoV-2结构蛋白诱导的免疫应答特点以及疫苗的研发提供了参考.Objective To evaluate the in vivo immunogenicity of the full-length N protein of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)derived from mammalian cell eukaryotic system or E.coli prokaryotic system,as well as in the combination with S1 protein in mice.Methods The protein was mixed with aluminum hydroxide and CpG adjuvant and injected into muscle of the mice for immunization.A booster immunization was performed 4 weeks after the initial immunization.Binding and neutralizing antibody levels were detected by ELISA and SARS-CoV-2 pseudovirus assay.The level of cellular immune response was detected by IFN-γELISpot.Results Both S1 protein and N protein booster immunizations induced high titers of IgG antibodies which were both significantly higher than those induced by the primary immunization(P<0.05).No significant difference was observed in the IgG antibody titers induced by N proteins derived from eukaryotic or prokaryotic systems(P>0.05).N protein and S1 protein combined with aluminum hydroxide and CpG adjuvant respectively induced a relatively balanced Th immune response.The results of the SARS-CoV-2 pseudovirus neutralization test showed that the S1 protein can induce the production of neutralizing antibodies,but the N protein cannot.For cellular immune response levels,both S1 protein and N protein induced the production of IFN-γsecreting cells.The N protein from the eukaryotic system demonstrated a stronger inducing effect than that of the prokaryotic system,and the difference was statistically significant(P<0.05).Compared to immunization with a single protein,combined immunization with N protein and S1 protein did not enhance humoral or cellular immunity in mice.Conclusions This study compared the immunogenicity of N proteins derived from different expression systems and the combined effects of N protein and S1 protein,providing a reference for further revealing the characteristics of immune responses induced by SARS-CoV-2 structural proteins and the development of vaccines.

关 键 词：新型冠状病毒 核衣壳蛋白 S1蛋白 免疫原性 

分 类 号：R373[医药卫生—病原生物学]