Characterization of uncultivable bat influenza virus using a replicative synthetic virus.-猫眼课题宝

使用复制性合成病毒对不可培养的蝙蝠流感病毒的表征。

DOI：

10.1371/journal.ppat.1004420

发表时间：

2014-10

期刊：

PLoS pathogens

影响因子：

6.7

通讯作者：

中科院分区：

医学1区

文献类型：

作者：

Zhou B;Ma J;Liu Q;Bawa B;Wang W;Shabman RS;Duff M;Lee J;Lang Y;Cao N;Nagy A;Lin X;Stockwell TB;Richt JA;Wentworth DE;Ma W

来源链接：

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4183581/?report=classic

蝙蝠携带许多病毒，这些病毒会定期传播给人类，导致疾病爆发（例如埃博拉病毒、SARS-CoV）。最近，在蝙蝠中发现了流感病毒样序列；然而，病毒无法培养。这一发现引起了人们对了解蝙蝠流感的进化历史和大流行潜力的极大兴趣。使用合成基因组学，我们无法拯救野生型蝙蝠病毒，但可以拯救一种改良的蝙蝠流感病毒，该病毒的 HA 和 NA 编码区被 A/PR/8/1934 (H1N1) 的编码区取代。这种改良的蝙蝠流感病毒在体外和小鼠体内能有效复制，导致严重的疾病。使用具有 A/swine/Texas/4199-2/1998 (H3N2) HA 和 NA 的蝙蝠流感病毒进行的其他研究表明，PR8 HA 和 NA 有助于对小鼠的致病性。与其他流感病毒不同，假设的工程截断可以减少 NS1 蛋白的干扰素拮抗作用，但并没有减弱蝙蝠流感。相比之下，替换蝙蝠流感PB2的假定毒力突变可显着减弱小鼠体内的病毒，并且引入假定毒力突变会增加其致病性。微型基因组复制研究和病毒重配实验表明，蝙蝠流感与 A 型或 B 型流感病毒的遗传和蛋白质相容性非常有限，但它很容易与另一种不同的蝙蝠流感病毒重配，这表明蝙蝠流感谱系可能代表正粘病毒科中的一个新属/种。总的来说，我们的数据表明，最近发现的蝙蝠流感病毒是真正的病毒，对人类构成的大流行威胁即使有，也很少。然而，它们为流感病毒的进化和基础生物学提供了新的见解。在两种不同蝙蝠物种中鉴定出流感病毒样序列，引起了人们对了解它们的生物学、与其他流感病毒混合的能力以及它们的公共卫生威胁的极大兴趣。不幸的是，无法从含有流感样核酸的样本中培养出蝙蝠流感病毒。我们使用合成基因组学策略来创建野生型蝙蝠流感病毒，或通过用甲型流感病毒模型取代表面糖蛋白来修饰的蝙蝠流感病毒。尽管流感病毒样颗粒是由两种合成基因组产生的，但只能培养改良的蝙蝠流感病毒。改良的蝙蝠流感病毒在体外可以有效复制，而 H1N1 流感病毒的改良版本会在小鼠体内引起严重的疾病。总的来说，我们的数据显示：（1）其他研究中鉴定的两种蝙蝠流感基因组具有复制能力，表明宿主细胞特异性是蝙蝠流感传播的主要限制，（2）蝙蝠流感NS1比甲型流感病毒模型更有效地拮抗宿主干扰素反应，（3）蝙蝠流感与甲型或乙型流感病毒在遗传和蛋白质上均不相容，（4）这些蝙蝠流感谱系几乎不会造成大流行威胁。

Bats harbor many viruses, which are periodically transmitted to humans resulting in outbreaks of disease (e.g., Ebola, SARS-CoV). Recently, influenza virus-like sequences were identified in bats; however, the viruses could not be cultured. This discovery aroused great interest in understanding the evolutionary history and pandemic potential of bat-influenza. Using synthetic genomics, we were unable to rescue the wild type bat virus, but could rescue a modified bat-influenza virus that had the HA and NA coding regions replaced with those of A/PR/8/1934 (H1N1). This modified bat-influenza virus replicated efficiently in vitro and in mice, resulting in severe disease. Additional studies using a bat-influenza virus that had the HA and NA of A/swine/Texas/4199-2/1998 (H3N2) showed that the PR8 HA and NA contributed to the pathogenicity in mice. Unlike other influenza viruses, engineering truncations hypothesized to reduce interferon antagonism into the NS1 protein didn't attenuate bat-influenza. In contrast, substitution of a putative virulence mutation from the bat-influenza PB2 significantly attenuated the virus in mice and introduction of a putative virulence mutation increased its pathogenicity. Mini-genome replication studies and virus reassortment experiments demonstrated that bat-influenza has very limited genetic and protein compatibility with Type A or Type B influenza viruses, yet it readily reassorts with another divergent bat-influenza virus, suggesting that the bat-influenza lineage may represent a new Genus/Species within the Orthomyxoviridae family. Collectively, our data indicate that the bat-influenza viruses recently identified are authentic viruses that pose little, if any, pandemic threat to humans; however, they provide new insights into the evolution and basic biology of influenza viruses. The identification of influenza virus-like sequences in two different bat species has generated great interest in understanding their biology, ability to mix with other influenza viruses, and their public health threat. Unfortunately, bat-influenza viruses couldn't be cultured from the samples containing the influenza-like nucleic acids. We used synthetic genomics strategies to create wild type bat-influenza, or bat-influenza modified by substituting the surface glycoproteins with those of model influenza A viruses. Although influenza virus-like particles were produced from both synthetic genomes, only the modified bat-influenza viruses could be cultured. The modified bat-influenza viruses replicated efficiently in vitro and an H1N1 modified version caused severe disease in mice. Collectively our data show: (1) the two bat-flu genomes identified in other studies are replication competent, suggesting that host cell specificity is the major limitation for propagation of bat-influenza, (2) bat-influenza NS1 antagonizes host interferon response more efficiently than that of a model influenza A virus, (3) bat-influenza has both genetic and protein incompatibility with influenza A or B viruses, and (4) that these bat-influenza lineages pose little pandemic threat.