HVR1-mediated antibody evasion of highly infectious in vivo adapted HCV in humanised mice.
HVR1-mediated antibody evasion of highly infectious in vivo adapted HCV in humanised mice.
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HVR1 介导的人源化小鼠体内高感染性 HCV 抗体逃避。
DOI：
10.1136/gutjnl-2015-310300
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发表时间：
2016
期刊：
影响因子：
24.5
通讯作者：
Bukh,Jens
中科院分区：
文献类型：
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作者：
Prentoe,Jannick;Verhoye,Lieven;VelázquezMoctezuma,Rodrigo;Buysschaert,Caroline;Farhoudi,Ali;Wang,Richard;Alter,Harvey;Meuleman,Philip;Bukh,Jens
HCV是全球慢性肝病的主要原因，但中和抗体（nAb）在其自然史中的作用仍然不清楚。我们分析了高变区1（HVR 1）在体内对HCV病毒粒子特性的作用，包括nAb易感性。设计分析感染细胞培养衍生的原型基因型2a重组J6/JFH 1或HVR 1缺失变体J6/JFH 1 Δ HVR 1的人肝嵌合小鼠的HCV，鉴定了适应性突变，并通过反向遗传学在Huh7.5和CD 81缺陷型S29细胞中进行了分析。结果在体内，J6/JFH 1和J6/JFH 1 Δ HVR 1依赖于非结构蛋白NS 2的867-876位氨基酸的单取代。鉴定的A876 P-取代导致基因组稳定性增加4.7倍。在体外，NS 2取代通过增加病毒组装而使感染性增强5-10倍。小鼠来源的mJ 6/JFH 1A 876 P和mJ 6/JFH 1 Δ HVR 1/A876 P病毒显示相似的异质密度，为1.02-1.1 g/mL。负载异源患者H（基因型1a）免疫球蛋白的人肝嵌合小鼠对mJ 6/JFH 1 A876 P具有部分保护作用，对mJ 6/JFH 1 Δ HVR 1/A876 P具有完全保护作用。有趣的是，我们在mJ 6/JFH 1A 876 P中发现了一个推定的逃逸突变D476 G。这种突变在高变区2赋予6.6倍的抗H 06 IgG在vitro.ConclusionsThe A876 P-取代桥梁在体外和体内研究使用J6/JFH 1为基础的重组体。我们提供了第一个体内证据表明HVR 1保护跨基因型保守的HCV中和表位，这主张使用HVR 1缺失的病毒作为疫苗抗原来增强广泛反应性保护性nAb应答的可能性。
ObjectiveHCV is a major cause of chronic liver disease worldwide, but the role of neutralising antibodies (nAbs) in its natural history remains poorly defined. We analysed the in vivo role of hypervariable region 1 (HVR1) for HCV virion properties, including nAb susceptibility.DesignAnalysis of HCV from human liver chimeric mice infected with cell-culture-derived prototype genotype 2a recombinant J6/JFH1 or HVR1-deleted variant J6/JFH1ΔHVR1identified adaptive mutations, which were analysed by reverse genetics in Huh7.5 and CD81-deficient S29 cells. The increased in vivo genomic stability of the adapted viruses facilitated ex vivo density analysis by ultracentrifugation and in vivo neutralisation experiments addressing the role of HVR1.ResultsIn vivo, J6/JFH1 and J6/JFH1ΔHVR1depended on single substitutions within amino acids 867–876 in non-structural protein, NS2. The identified A876P-substitution resulted in a 4.7-fold increase in genomic stability. In vitro, NS2 substitutions enhanced infectivity 5–10-fold by increasing virus assembly. Mouse-derived mJ6/JFH1A876Pand mJ6/JFH1ΔHVR1/A876Pviruses displayed similar heterogeneous densities of 1.02–1.1 g/mL. Human liver chimeric mice loaded with heterologous patient H (genotype 1a) immunoglobulin had partial protection against mJ6/JFH1A876Pand complete protection against mJ6/JFH1ΔHVR1/A876P. Interestingly, we identified a putative escape mutation, D476G, in mJ6/JFH1A876P. This mutation in hypervariable region 2 conferred 6.6-fold resistance against H06 IgG in vitro.ConclusionsThe A876P-substitution bridges in vitro and in vivo studies using J6/JFH1-based recombinants. We provide the first in vivo evidence that HVR1 protects cross-genotype conserved HCV neutralisation epitopes, which advocates the possibility of using HVR1-deleted viruses as vaccine antigens to boost broadly reactive protective nAb responses.