CD8+ T细胞在寨卡病毒诱发小头症过程中介导神经损伤机制研究

Zika virus infection increases the incidence of Guillain-Bahrain syndrome. CD8+ T cell is associated with Immune-mediated neuroinflammation, such as Guillain-Bahrain syndrome and Multiple Sclerosis. Current studies have shown that CD8+ T cells play an important role in the antiviral process of Zika virus infection. However, the mechanism of Zika-specific CD8+ T cell-induced nerve injury remains unclear. We previously studied the regulation of immune response in mice infected with different toxic Zika virus strains, and found that both strains caused up-regulation of CD8+ T cells, whereas virulent strains activated CD8+ T cells more strongly. We still don't know which are Zika-specific CD8+ T cell subsets, and how to be regulated? Therefore, the project plans to identify the Zika-specific CD8+ T cell subsets associated with nerve injury by single-cell sequencing, and identify the ZIKV-specific CD8+ T cell subtype-related expression genes and lncRNA profiles by means of totalRNA sequencing. Using these data and nerve injury degree data, we can identify the mechanism of CD8 T cells mediating nerve injury during Zika virus-induced microcephaly. This project provides a theoretical reference for the diagnosis and prevention of nerve damage caused by Zika virus, and helps to understand the mechanism of immune-mediated neuroinflammation.

寨卡病毒感染导致的格林-巴利综合症等神经性疾病发生与CD8+ T细胞功能有关。目前研究表明，CD8+ T细胞在寨卡病毒感染的抗病毒过程中起重要作用，但对其是否参与神经损伤过程还知之甚少。我们之前研究表明，不同毒性寨卡毒株感染小鼠大脑后，两种毒株都能引起CD8+ T细胞的上调，而强毒力毒株能引起更强的CD8+ T细胞活化。但是，我们仍旧不清楚寨卡毒株特异性的CD8+ T细胞亚型有哪些？它们是如何被调控的？因此本课题拟采用单细胞测序技术鉴定神经损伤关联的寨卡特异性CD8+ T细胞亚型，并结合total RNA测序的方法鉴定寨卡特异性的CD8+ T细胞亚型相关基因表达谱，构建基因调控网络，鉴定其诱发神经损伤的分子机制。本课题将为理解寨卡病毒导致的神经损伤提供理论参考，也有助于深入理解免疫介导的神经炎症发生机制。

寨卡病毒感染导致的格林-巴利综合症等神经性疾病发生与CD8+ T细胞功能有关。目前研究表明，CD8+ T细胞在寨卡病毒感染的抗病毒过程中起重要作用，但对其是否参与神经损伤过程还知之甚少。我们通过比较不同毒力寨卡毒株发现，两种毒株都能引起CD8+ T细胞的上调，而强毒力毒株能引起更强的CD8+ T细胞活化，同时刺激数个Tnf家族基因的上调表达。进一步我们通过单细胞测序技术，我们分析了基于弱毒株FSS构建S139N单突变株对免疫系统应答的影响，发现S139N突变株诱发的表达谱与GZ01毒株类似。毒性T细胞在感染7dpi与14dpi时的增殖数量都弱于FSS毒株。然而在21dpi时都高于FSS毒株。TCR分析显示出类似的结果。胶质细胞的结果显示GZ01毒株在早期诱发与神经疾病修复关联的小胶质细胞Microglia_active_Gpnmb亚群的增殖，同时应答感染的细胞亚群Microglia_active_Lyz2也在早期迅速增加。而S139N毒株仅Microglia_active_Lyz2亚群在7dpi数量高于FSS。这些结果显示S139N毒株侵染后更早的被小胶质细胞检测到。然而令人意外的是S139N不具备GZ01毒株中的免疫抑制相关基因，两者的适应性免疫应答却表现出极高的相似性。这些结果暗示S139N突变可能具有一定的免疫抑制能力，相关结论仍需实验验证。本课题的开展是我们更深入的理解了寨卡病毒导致神经损伤的机制，为寨卡病毒的抗病毒治疗提供理论参考。