Viral tools and monosynaptic tracers for studying SARS-CoV2 neurotropism and neuronal transmission

越来越多的证据表明，大流行的SARS-CoV2可以感染中枢神经系统细胞。新冠肺炎危重症患者呼吸衰竭，嗅觉神经元感染可能是味觉、嗅觉丧失和脑干感染的主要原因。从周围神经到中枢神经系统的跨神经元转移在SARS-CoV1中已有描述。由于对BSL3实验室的要求和小鼠（神经生物学中主要的动物模型）的低许可性，严重阻碍了SARS病毒神经向性和跨神经元传播的实验研究。我们之前已经建立了缺陷狂犬病毒的单突触示踪，并将在这里应用该系统来研究SARS-CoV2跨膜刺突蛋白(S)在人细胞中介导的嗜神经性，以及S突变体在小鼠细胞中适应小鼠受体mACE2。除了鉴定S靶细胞外，还将确定S介导的病毒RNPs的跨突触传递能力。

There is accumulating evidence that the pandemic SARS-CoV2 can infect cells of the CNS. Infection of olfactory neurons may be responsible for the loss of taste and smell and infection of the brainstem for respiratory failure of critically ill COVID-19 patients. Transneuronal transfer from peripheral nerves to the CNS has been described before for SARS-CoV1. Experimental investigation of the neurotropism and transneuronal spread, by SARS viruses is severely hampered by the requirement for BSL3 laboratories and the low permissivity of mice, which are the major animal models in neurobiology. We have previously established monosynaptic tracing with defective rabies viruses and will here adapt the system to study the neurotropism mediated by the SARS-CoV2 transmembrane Spike protein (S) in human cells, and of S mutants adapted to the mouse receptor mACE2 in mouse cells. In addition to the identification of S target cells, the capacity of S-mediated transsynaptic transmission of viral RNPs will be determined.