Herpes Simplex Virus 1 Enters Human Keratinocytes by a Nectin-1-Dependent, Rapid Plasma Membrane Fusion Pathway That Functions at Low Temperature
Herpes Simplex Virus 1 Enters Human Keratinocytes by a Nectin-1-Dependent, Rapid Plasma Membrane Fusion Pathway That Functions at Low Temperature
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DOI：
10.1128/jvi.01582-16
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发表时间：
2016-11-01
影响因子：
5.4
通讯作者：
Elliott, Gillian
中科院分区：
文献类型：
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作者：
Sayers, Charlotte L.;Elliott, Gillian
单纯疱疹病毒1（HSV-1）通过主要由角质形成细胞组成的复层上皮感染人类。HSV-1进入角质形成细胞的途径一直是有限研究的主题，但提出涉及pH依赖性内吞作用，需要gD结合受体nectin-1。在这里，我们已经利用nTERT人角质形成细胞系作为一个新的模型，用于解剖HSV-1进入宿主的机制。虽然是永生化的，但这些细胞仍然保留了原代细胞的正常生长和分化特性。使用短干扰RNA（siRNA）耗竭研究，我们证实，尽管nTERT细胞表达高水平的替代gD受体HVEM，HSV-1需要nectin-1，而不是HVEM，进入这些细胞。引人注目的是，病毒进入nTERT细胞发生不寻常的速度，使最大的渗透在5分钟内实现。此外，HSV-1能够进入角质形成细胞，但不是其他类型的细胞在温度低至7摄氏度，条件下，内吞作用被证明是完全抑制。在37 ℃和7 ℃的早期进入事件的透射电子显微镜鉴定了许多位于质膜下的裸露病毒衣壳的例子，没有证据表明细胞质囊泡中有病毒粒子。综上所述，这些结果表明，HSV-1使用nectin-1受体进入人角质形成细胞通过以前未表征的快速质膜融合途径，在低温下发挥作用。这些研究具有重要的意义，目前了解HSV-1和其相关的体内靶细胞之间的关系。重要的是，抗病毒治疗的黄金标准，任何人类病毒感染是防止病毒进入宿主细胞。在HSV-1的情况下，人类的原发性感染开始于皮肤的表皮或口腔粘膜，在那里病毒感染角质形成细胞，因此重要的是了解HSV-1进入这种细胞类型所涉及的分子事件。尽管如此，很少有研究专门研究进入这些相关的人类细胞。我们的研究结果揭示了一种新的病毒进入途径，该途径特异于角质形成细胞，涉及快速进入，并在低温下发挥作用。这可能反映了HSV-1通过皮肤进入宿主时所遇到的环境条件，并强调了在生理相关细胞中研究病毒-宿主相互作用的重要性。
Herpes simplex virus 1 (HSV-1) infects humans through stratified epithelia that are composed primarily of keratinocytes. The route of HSV-1 entry into keratinocytes has been the subject of limited investigation, but it is proposed to involve pH-dependent endocytosis, requiring the gD-binding receptor nectin-1. Here, we have utilized the nTERT human keratinocyte cell line as a new model for dissecting the mechanism of HSV-1 entry into the host. Although immortalized, these cells nonetheless retain normal growth and differentiation properties of primary cells. Using short interfering RNA (siRNA) depletion studies, we confirm that, despite nTERT cells expressing high levels of the alternative gD receptor HVEM, HSV-1 requires nectin-1, not HVEM, to enter these cells. Strikingly, virus entry into nTERT cells occurred with unusual rapidity, such that maximum penetration was achieved within 5 min. Moreover, HSV-1 was able to enter keratinocytes but not other cell types at temperatures as low as 7 degrees C, conditions where endocytosis was shown to be completely inhibited. Transmission electron microscopy of early entry events at both 37 degrees C and 7 degrees C identified numerous examples of naked virus capsids located immediately beneath the plasma membrane, with no evidence of virions in cytoplasmic vesicles. Taken together, these results imply that HSV-1 uses the nectin-1 receptor to enter human keratinocyte cells via a previously uncharacterized rapid plasma membrane fusion pathway that functions at low temperature. These studies have important implications for current understanding of the relationship between HSV-1 and its relevant in vivo target cell.IMPORTANCEThe gold standard of antiviral treatment for any human virus infection is the prevention of virus entry into the host cell. In the case of HSV-1, primary infection in the human begins in the epidermis of the skin or the oral mucosa, where the virus infects keratinocytes, and it is therefore important to understand the molecular events involved in HSV-1 entry into this cell type. Nonetheless, few studies have looked specifically at entry into these relevant human cells. Our results reveal a new route for virus entry that is specific to keratinocytes, involves rapid entry, and functions at low temperatures. This may reflect the environmental conditions encountered by HSV-1 when entering its host through the skin and emphasizes the importance of studying virus-host interactions in physiologically relevant cells.