African swine fever virus uses macropinocytosis to enter host cells.
African swine fever virus uses macropinocytosis to enter host cells.
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DOI：
10.1371/journal.ppat.1002754
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发表时间：
2012
期刊：
影响因子：
6.7
通讯作者：
Revilla Y
中科院分区：
文献类型：
--
作者：
Sánchez EG;Quintas A;Pérez-Núñez D;Nogal M;Barroso S;Carrascosa ÁL;Revilla Y
非洲猪瘟(ASF)是由一种大而高致病性的DNA病毒--非洲猪瘟病毒(ASFV)引起的，造成严重的经济损失和蔓延威胁。目前，没有针对ASF的特定保护措施或疫苗，尽管这种疾病在撒哈拉以南非洲持续发生、2007年在高加索地区最近爆发以及可能向邻国传播的风险很高。尽管病毒进入是开发保护工具的一个重要目标，但对ASFV进入机制的了解仍然非常有限。虽然早期的研究表明，病毒是通过受体介导的内吞作用进入细胞的，但ASFV使用的具体机制仍然不确定。在这里，我们使用适应于在Vero细胞中生长的ASFV强毒株Ba71(Ba71V)和强毒株E70来证明ASFV的进入和内化包括大吞噬的大部分特征。通过光学显微镜和电子显微镜的结合，我们发现该病毒引起细胞膜扰动、起泡和皱纹。我们还发现，病毒粒子的内化依赖于肌动蛋白重组，Na+/H+交换器的活性，以及典型的大胞内吞饮机制的信号事件。病毒进入细胞似乎直接刺激葡聚糖摄取、肌动蛋白极化和EGFR、PI3K-Akt、Ak1和rac1的激活。抑制巨噬细胞吞噬的这些关键调节因子，以及药物EIPA的治疗，导致ASFV进入和感染的显著减少。总之，这项研究首次确定了ASFV进入的整个途径，包括感染病毒所需的关键细胞因子和涉及的细胞信号。ASFV是一种高致病性人畜共患病病毒，可造成严重的经济损失和生物恐怖主义威胁。到目前为止，还没有针对ASFV的疫苗。最近出现了从高加索地区通过欧盟国家传播ASFV的强烈危险，因此迫切需要获得预防这种病毒的知识和工具。尽管如此，我们对ASFV如何进入宿主细胞的了解非常有限。彻底了解这一过程将使设计有针对性的抗病毒疗法和疫苗开发成为可能。本研究清楚地定义了ASFV细胞吸收的关键步骤，以及导致病毒进入细胞的宿主因素。我们的结果表明，ASFV摄取的主要机制是一个类似大胞吞饮的过程，涉及细胞膜扰动、肌动蛋白极化、Na+/H+膜通道的活动，以及典型的大胞吞机制的信号过程，如rac1-pak1途径、PI3K和酪氨酸激酶激活。这些发现有助于理解ASFV是如何感染细胞的，并表明巨噬细胞吞噬功能障碍可能有助于损害感染和疫苗开发。
African swine fever (ASF) is caused by a large and highly pathogenic DNA virus, African swine fever virus (ASFV), which provokes severe economic losses and expansion threats. Presently, no specific protection or vaccine against ASF is available, despite the high hazard that the continued occurrence of the disease in sub-Saharan Africa, the recent outbreak in the Caucasus in 2007, and the potential dissemination to neighboring countries, represents. Although virus entry is a remarkable target for the development of protection tools, knowledge of the ASFV entry mechanism is still very limited. Whereas early studies have proposed that the virus enters cells through receptor-mediated endocytosis, the specific mechanism used by ASFV remains uncertain. Here we used the ASFV virulent isolate Ba71, adapted to grow in Vero cells (Ba71V), and the virulent strain E70 to demonstrate that entry and internalization of ASFV includes most of the features of macropinocytosis. By a combination of optical and electron microscopy, we show that the virus causes cytoplasm membrane perturbation, blebbing and ruffles. We have also found that internalization of the virions depends on actin reorganization, activity of Na+/H+ exchangers, and signaling events typical of the macropinocytic mechanism of endocytosis. The entry of virus into cells appears to directly stimulate dextran uptake, actin polarization and EGFR, PI3K-Akt, Pak1 and Rac1 activation. Inhibition of these key regulators of macropinocytosis, as well as treatment with the drug EIPA, results in a considerable decrease in ASFV entry and infection. In conclusion, this study identifies for the first time the whole pathway for ASFV entry, including the key cellular factors required for the uptake of the virus and the cell signaling involved. ASFV is a highly pathogenic zoonotic virus, which can cause severe economic losses and bioterrorism threats. No vaccine against ASFV is available so far. A strong hazard of ASFV dissemination through EU countries from Caucasian areas has recently emerged, thus making urgent to acquire knowledge and tools for protection against this virus. Despite that, our understanding of how ASFV enters host cells is very limited. A thorough understanding of this process would enable to design targeted antiviral therapies and vaccine development. The present study clearly defines key steps of ASFV cellular uptake, as well as the host factors responsible for permitting virus entry into cells. Our results indicate that the primary mechanism of ASFV uptake is a macropinocytosis-like process, that involves cellular membrane perturbation, actin polarization, activity of Na+/H+ membrane channels, and signaling proceedings typical of the macropinocytic mechanism of endocytosis, such as Rac1-Pak1 pathways, PI3K and tyrosine-kinases activation. These findings help understanding how ASFV infects cells and suggest that disturbance of macropinocytosis may be useful in the impairment of infection and vaccine development.
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影响因子：
6.7
作者：
Castelló A;Quintas A;Sánchez EG;Sabina P;Nogal M;Carrasco L;Revilla Y
通讯作者：
Revilla Y
影响因子：
6.4
作者：
Aleksandrowicz, Paulina;Marzi, Andrea;Schnittler, Hans-Joachim
通讯作者：
Schnittler, Hans-Joachim
DOI：
10.1073/pnas.0803711105
发表时间：
2008-08-19
影响因子：
11.1
作者：
Chen Chen;Zhuang, Xiaowei
通讯作者：
Zhuang, Xiaowei
影响因子：
3.7
作者：
ALCAMI, A;CARRASCOSA, AL;VINUELA, E
通讯作者：
VINUELA, E
影响因子：
5.4
作者：
CARRASCOSA, JL;GONZALEZ, P;VINUELA, E
通讯作者：
VINUELA, E