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标题: AASLD2018[534]e抗原是一种干扰素抗性 允许乙型肝炎病毒感染的 [打印本页]

作者: StephenW    时间: 2018-10-24 19:45     标题: AASLD2018[534]e抗原是一种干扰素抗性 允许乙型肝炎病毒感染的

534
The e Antigen Is an Interferon Resistance
Protein That Allows the Hepatitis B Virus to
Evade the Early Immune Response.
Zina Valaydon1, Gregor Ebert2, Liana Mackiewicz3, Simon
Preston4, Paul V. Desmond5, Vitina Sozzi6, Peter Revill7,
Alexander J. V. Thompson8 and Marc Pellegrini2, (1)
Gastroenterology, St Vincent’s Hospital, Melbourne, (2)Walter
and Eliza Hall Institute, (3)Walter an Eliza Hall Institute, (4)
Wehi, (5)Gastroenterology, St Vincent’s Hospital Melbourne,
(6)Victorian Infectious Disease Reference Laboratory, (7)The
University of Melbourne, (8)Department of Gastroenterology,
St. Vincent’s Hospital
Background: The precore antigen, HBeAg, is thought
to be a tolerogen in the natural history of Hepatitis B virus
(HBV) infection. However, the exact underlying immune
mechanisms are unknown. The basal core promoter (BCP)
and precore (PC) variants of the hepatitis B reduce and
abolish HBeAg production, respectively, and are associated
with increased risk of cirrhosis and hepatocellular carcinoma.
We used a novel immunocompetent mouse model of HBV
infection to study viral kinetics and immunological differences
between wild type (WT) virus and HBV variants with little
or no HBeAg.Methods: An HBV 1.2 overlength genome
was flanked by adeno-associated virus inverted terminal
repeats within a plasmid vector. The genome was mutated
using site-directed mutagenesis to introduce dual A1762T/
G1764A BCP and G1896A PC mutations. WT, PC and
BCP plasmids were hydrodynamically injected in the tail
vein of C57/BL6 mice. Interferon-alpha receptor knockout
(IFNaR-KO) and interferon-gamma knockout mice were
used to investigate the role of Type 1 interferon (IFN) and
IFN-gamma respectively. To investigate the role of tumour
necrosis factor-alpha (TNF-a), mice were treated with TNF-a
neutralizing antibodies. Viral DNA was extracted from serum
and quantitated by qPCR and serology was performed.
Transcriptomic and proteomic studies were carried out on
liver tissue to determine differences in expression profile
between mutants and WT. Results: Significant differences
in viral kinetics were seen with the BCP and PC mutants
vs. WT (Fig1a). There was a rapid drop in viral load (VL) in
the mutants in the early phase of infection in weeks 1-7 (p
<0.03 vs. WT at week 2-7). ALT levels were also significantly
increased in mutants vs WT (Mean ALT 128 IU/ml vs 40 IU/
ml, p<0.02). To further interrogate the phenomenon a series
of immune experiments were performed. The experiment was
then performed in IFNaR-KO mice. There was a significant
increase in VL in both PC and BCP mutants (p <0.05) and the
early difference in VL between mutant and WT strains was
abolished when the influence of IFN-a was removed (Fig 1b).
No effect was seen with the neutralization of The IFN-gamma
or TNF pathways. Transcriptomic study of liver tissue showed
that there is a significant upregulation of the Type 1 interferon
pathway and gene signatures in HBeAg negative mutants vs.
WT (P=0.04)- Fig 2. Proteomic studies show that interferon
related proteins are significantly overexpressed in HBeAg
negative mutants (Fig 3). Conclusion: These studies shows
that in Type 1 IFN is a key mediator of the early innate immune
response and that in absence of HBeAg, HBV is much more
susceptible to Type 1 IFN. This is supported by viral kinetic
differences, immune studies as well as transcriptomic and
proteomics data. Collectively our studies show that HBeAg is
an IFN resistance protein.

作者: StephenW    时间: 2018-10-24 19:45

534
e抗原是一种干扰素抗性
允许乙型肝炎病毒感染的蛋白质
躲避早期免疫反应。
Zina Valaydon1,Gregor Ebert2,Liana Mackiewicz3,Simon
Preston4,Paul V. Desmond5,Vitina Sozzi6,Peter Revill7,
Alexander J. V. Thompson8和Marc Pellegrini2,(1)
墨尔本圣文森特医院消化内科,(2)沃尔特
和伊丽莎霍尔研究所,(3)沃尔特伊丽莎霍尔研究所,(4)
Wehi,(5)墨尔本圣文森特医院消化内科,
(6)维多利亚州传染病参考实验室,(7)
墨尔本大学,(8)消化系,
圣文森特医院
背景:人们认为前核心抗原HBeAg
成为乙型肝炎病毒自然史中的耐受原
(HBV)感染。然而,确切的潜在免疫
机制尚不清楚。基础核心启动子(BCP)
和乙型肝炎的前核心(PC)变异减少和
分别取消HBeAg的生产并与之相关
肝硬化和肝细胞癌的风险增加。
我们使用了一种新的HBV免疫活性小鼠模型
感染以研究病毒动力学和免疫学差异
野生型(WT)病毒与HBV变种之间的差异很小
或没有HBeAg.Methods:HBV 1.2超长基因组
两侧是腺相关病毒倒置末端
在质粒载体内重复。基因组发生了突变
利用定点诱变引入双A1762T /
G1764A BCP和G1896A PC突变。 WT,PC和
BCP质粒在尾部流体动力学注射
C57 / BL6小鼠的静脉。干扰素-α受体敲除
(IFNaR-KO)和干扰素-γ敲除小鼠
用于研究1型干扰素(IFN)和干扰素的作用
分别为IFN-γ。调查肿瘤的作用
用TNF-α处理小鼠坏死因子-α(TNF-α)
中和抗体。从血清中提取病毒DNA
并通过qPCR和血清学定量。
进行了转录组学和蛋白质组学研究
肝组织确定表达谱的差异
在突变体和WT之间。结果:显着差异
用BCP和PC突变体观察病毒动力学
与WT(图1a)。病毒载量(VL)迅速下降
第1-7周感染早期的突变体(p
在第2-7周时相对于WT <0.03)。 ALT水平也显着
突变体与WT相比增加(平均ALT 128 IU / ml vs 40 IU /
ml,p <0.02)。进一步询问一系列现象
进行了免疫实验。实验是
然后在IFNaR-KO小鼠中进行。有一个重要的
PC和BCP突变体中VL的增加(p <0.05)和
突变体和WT菌株之间VL的早期差异是
当IFN-α的影响被消除时废除(图1b)。
IFN-γ的中和没有看到效果
或TNF途径。肝组织的转录组学研究显示
1型干扰素显着上调
HBeAg阴性突变体的通路和基因特征
WT(P = 0.04) - 图2.蛋白质组学研究表明干扰素
相关蛋白在HBeAg中显着过表达
阴性突变体(图3)。结论:这些研究表明
在1型干扰素中,IFN是早期先天免疫的关键介质
反应和没有HBeAg,HBV更多
易患1型IFN。这是由病毒动力学支持的
差异,免疫研究以及转录组学和
蛋白质组学数据。总的来说,我们的研究表明HBeAg是
IFN抗性蛋白。
作者: 齐欢畅    时间: 2018-10-25 20:35

关注
作者: StephenW    时间: 2018-10-25 20:56

回复 齐欢畅 的帖子

研究Birinapant治疗HBV的科学家们(Pellegrini, Ebert)现在进行更多的HBV研究,与其他HBV专家.
作者: 齐欢畅    时间: 2018-10-25 21:38

StephenW 发表于 2018-10-25 20:56
回复 齐欢畅 的帖子

研究Birinapant治疗HBV的科学家们(Pellegrini, Ebert)现在进行更多的HBV研究,与其他H ...

有什么结果呢?
作者: sky8989    时间: 2018-10-25 21:44

哈哈,都是临床前呗。不过越多的投入就多一份攻克的可能。我比较心急吧,都是关注2期的。如果2期全部失败,那乙肝攻克就再等10年吧
作者: 齐欢畅    时间: 2018-10-25 21:50

越多越好,研究。
作者: StephenW    时间: 2018-10-26 14:28

回复 齐欢畅 的帖子

有什么结果呢?

我不完全理解他们的上述研究. 他们研究e-抗原与免疫系统的相互作用(干扰素α和γ).
作者: 齐欢畅    时间: 2018-10-26 20:15

e抗原可以刺激产生干扰素
作者: StephenW    时间: 2018-10-26 20:44

回复 齐欢畅 的帖子

在他们的研究中,他们表明HBeAg使干扰素效果降低.但为什么干扰素用于治疗HBeAg阳性患者?这就是干扰素需要至少治疗48周的原因吗?
作者: 齐欢畅    时间: 2018-10-26 21:02

StephenW 发表于 2018-10-26 20:44
回复 齐欢畅 的帖子

在他们的研究中,他们表明HBeAg使干扰素效果降低.但为什么干扰素用于治疗HBeAg阳性患 ...

e抗原可以刺激产生干扰素,也能抑制干扰素,这就是免疫耐受机制,
成也萧何败也萧何。
或者说,过犹不及
也可以说,量变引起质变
也可以说是,天之道,损有余以补不足。




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