Laboratory of Neuroimmunovirology, INRS-Institut Armand-Frappier, Institut national de la recherche scientifique, Université du Québec, 531 boulevard des Prairies, Laval, QC, H7V IB7, Canada,
Adv Exp Med Biol. 2014;807:75-96. doi: 10.1007/978-81-322-1777-0_6.
In humans, viral infections of the respiratory tract are a leading cause of morbidity and mortality worldwide. Several recognized respiratory viral agents have a neuroinvasive capacity since they can spread from the respiratory tract to the central nervous system (CNS). Once there, infection of CNS cells (neurotropism) could lead to human health problems, such as encephalitis and long-term neurological diseases. Among the various respiratory viruses, coronaviruses are important pathogens of humans and animals. Human Coronaviruses (HCoV) usually infect the upper respiratory tract, where they are mainly associated with common colds. However, in more vulnerable populations, such as newborns, infants, the elderly, and immune-compromised individuals, they can also affect the lower respiratory tract, leading to pneumonia, exacerbations of asthma, respiratory distress syndrome, or even severe acute respiratory syndrome (SARS). The respiratory involvement of HCoV has been clearly established since the 1960s. In addition, for almost three decades now, the scientific literature has also demonstrated that HCoV are neuroinvasive and neurotropic and could induce an overactivation of the immune system, in part by participating in the activation of autoreactive immune cells that could be associated with autoimmunity in susceptible individuals. Furthermore, it was shown that in the murine CNS, neurons are the main target of infection, which causes these essential cells to undergo degeneration and eventually die by some form of programmed cell death after virus infection. Moreover, it appears that the viral surface glycoprotein (S) represents an important factor in the neurodegenerative process. Given all these properties, it has been suggested that these recognized human respiratory pathogens could be associated with the triggering or the exacerbation of neurological diseases for which the etiology remains unknown or poorly understood.
在人类中，呼吸道病毒感染是全球发病率和死亡率的主要原因。一些已被认识的呼吸道病毒病原体具有神经侵袭能力，因为它们可以从呼吸道传播到中枢神经系统（CNS）。一旦到达那里，中枢神经系统细胞的感染（神经嗜性）可能导致人类健康问题，如脑炎和长期神经系统疾病。在各种呼吸道病毒中，冠状病毒是人类和动物的重要病原体。人类冠状病毒（HCoV）通常感染上呼吸道，主要与普通感冒有关。然而，在更脆弱的人群中，如新生儿、婴儿、老年人和免疫功能低下的个体，它们也可能感染下呼吸道，导致肺炎、哮喘恶化、呼吸窘迫综合征，甚至严重急性呼吸综合征（SARS）。自 20 世纪 60 年代以来，HCoV 的呼吸道感染已经得到明确证实。此外，近三十年来，科学文献还表明，HCoV 具有神经侵袭性和神经嗜性，并可能导致免疫系统过度激活，部分原因是参与激活自身反应性免疫细胞，这些细胞可能与易感个体的自身免疫有关。此外，研究表明，在鼠类中枢神经系统中，神经元是感染的主要靶标，这导致这些重要细胞在病毒感染后通过某种形式的程序性细胞死亡发生退化并最终死亡。此外，似乎病毒表面糖蛋白（S）是神经退行性过程中的一个重要因素。鉴于所有这些特性，有人提出，这些已被认识的人类呼吸道病原体可能与尚未明确或尚未充分了解的神经疾病的触发或恶化有关。
