How the Novel Coronavirus Attacks the Brain

SARS-CoV-2感染患者的神经学表现是多样和独特的 表现形式，包括嗅觉丧失、精神错乱和精神状态改变，当小说的过程 冠状病毒病(新冠肺炎)因神经系统受到侮辱而变得复杂。鼻咽部和 鼻腔是高病毒载量的蓄水池，嗅觉组织含有关键的受体和蛋白酶 可以促进病毒在细胞水平上的进入和复制。脑细胞的下游机制 入侵和整合仍然知之甚少，特别是SARS-CoV-2可能如何煽动扩散 对神经的影响。新冠肺炎患者持续严重的细胞因子风暴，两者之间的相互作用 炎症和凝血与内皮损伤相结合，可能导致血栓栓子事件，以及 小胶质细胞激活导致神经元损伤。患者还存在长期的脑部后遗症 新冠肺炎的症状包括“大脑迷雾”、注意力难以集中、短期和工作记忆受损、疲劳、 头痛、自主神经障碍和失眠，以及这些症状的神经病理学基础尚不清楚。 新冠肺炎患者死亡前后特定脑区的适当评估 出现神经症状将有助于更好地理解限制大脑的可能目标 损坏。此外，SARS-CoV-2如何影响大脑的教训可能会为我们提供对可推广的 神经炎症在神经退行性疾病中的作用机制。我们的目标是确定： 1.新冠肺炎患者摄入时出现神经系统症状(NP-CoV)是否发生变化 炎症和凝血调节基因的脑表达与无(COVS)和 年龄和性别匹配的非新冠肺炎对照组(续)。我们将把整个转录组绘制成 脑组织切片采用单核RNA测序(sn-RNA-seq，10X基因组学)。我们将验证并 使用双链技术量化神经元、神经胶质细胞和血管相关细胞上候选mRNAs的表达 RNAScope®(ACDBio)，正如我们在CONT.2.NP-Cov是否有大脑升高 促炎标记物。我们将运行人类细胞因子/趋化因子/生长因子小组(48 Plex Kit， 并对细胞因子、趋化因子和生长因子进行量化。我们将把它们的表达映射到神经元上 和胶质细胞，使用双重免疫组织化学(IHC)，正如我们在CONT.3.如果NP-cov升高 脑部小胶质细胞激活。双免疫组化法检测小胶质细胞标志物TSPO、CD11b、Iba1 (电离钙结合接头分子)、神经元标志物和细胞定量的体视学。 将计算激活的(变形体)和静息的(小细胞体和精细的细突起)小胶质细胞，以及 将空间关系映射到神经元。4.NP-Cov是否存在神经元密度降低和树突分枝现象。 用双免疫组织化学法检测神经元标志物NeuN和神经丝、立体视探测器和神经荧光素(MBF) Inc.)，将量化神经元密度、树突长度和树枝形成，就像我们的初步研究中一样。

Presentations of patients infected with SARS-CoV-2 are varied and unique in their neurological manifestations, including loss of smell, confusion, and altered mental status, when the course of the novel coronavirus disease (COVID-19) is complicated by insults to the neurological system. The nasopharynx and nasal cavities are reservoirs for high viral load and olfactory tissue contains key receptors and proteases that may facilitate viral entry and replication at the cellular level. Downstream mechanisms of brain cellular invasion and integration remain poorly understood, particularly how SARS-CoV-2 may be instigating diffuse neurological effects. Patients with COVID-19 sustain a severe cytokine storm, the interplay between inflammation and coagulation combined with endothelial damage, may lead to thrombo-embolic events, and microglia activation leading to neuronal damage. Patients also present with long-term brain sequela of COVID-19, including “brain fog,” difficulties concentrating, impaired short-term and working memory, fatigue, headache, dysautonomia, and insomnia, and the neuropathological bases of these symptoms are unknown. Appropriate evaluation of specific brain regions from deceased patients with COVID-19 who did and did not present with neurological symptoms will allow for improved comprehension of possible targets to limit brain damage. Additionally, lessons from how SARS-CoV-2 affects the brain may provide insight into generalizable mechanisms for effects of neuroinflammation on neurodegenerative diseases. We aim to determine: 1. Whether COVID-19 patients with neurological presentations at the time of intake (NP-COVs) have altered brain expression of genes regulating inflammation and coagulation compared to those without (COVs) and non-COVID-19 age and sex matched controls (CONT). We will map the whole transcriptome in the entire brain tissue section using single nuclei RNA sequencing (sn-RNA-seq, 10X Genomics). We will validate and quantify candidate mRNAs expression on neurons, glia, and vasculature-associated cells, using Duplex RNAscope® (ACDBio), as we successfully performed in CONT. 2. Whether NP-COVs have elevated brain pro-inflammatory markers. We will run a Human Cytokine/Chemokine/Growth Factor Panel (48 Plex Kit, Milliopre) and quantify cytokines, chemokines and growth factors. We will map their expression on neurons and glia, using double immunohistochemistry (IHC), as we piloted in CONT. 3. If NP-COVs have elevated brain microglia activation. Using double-IHC for microglia markers TSPO (translocator protein), CD11b, Iba1 (Ionized calcium binding adaptor molecule), and neuronal markers, and stereology for cell quantification, we will compute activated (amoeboid) and resting (small cell body and elaborated thin processes) microglia, and map spatial relationship to neurons. 4. If NP-COVs have reduced neuronal density and dendrite arborization. Using double-IHC for neuronal marker NeuN and neurofilament, Stereoinvestigator and Neurolucida (MBF Inc.), will quantify neuron density, dendrite length and arborization, as in our pilot studies.