Perlman S, Jacobsen G, Afifi A
Department of Pediatrics, University of Iowa, Iowa City 52242.
Virology. 1989 Jun;170(2):556-60. doi: 10.1016/0042-6822(89)90446-7.
The route of entry into the central nervous system (CNS) of most neurtropic viruses has not been established. The coronavirus, mouse hepatitis virus strain JHM (MHV-JHM), causes acute encephalomyelitis and acute and chronic demyelinating diseases and is an important model system for virus-induced neurological disease. Suckling C57BL/6 mice infected intranasally with MHV-JHM develop either the acute encephalomyelitis or a late onset, symptomatic demyelinating encephalomyelitis, depending on whether they are nursed by unimmunized or immunized dams. Analysis by in situ hybridization was used to determine the route of entry of MHV-JHM into the CNS in these mice. At early times, viral RNA was detected only in the trigeminal and olfactory nerves and in their immediate connections in all mice. A few days later, MHV-JHM RNA was found throughout the brain in mice dying of the acute encephalomyelitis, but remained confined to the entry sites in mice which did not develop acute disease. These results suggest that MHV-JHM enters the CNS via an interneuronal route in all mice, but that the presence of maternal antibody prevents the dissemination of virus via extracellular fluid. In addition, MHV-JHM may establish low-level persistence in the trigeminal or olfactory nerve or in one of its connections in mice that do not develop acute encephalomyelitis.
大多数嗜神经病毒进入中枢神经系统（CNS）的途径尚未明确。冠状病毒，即小鼠肝炎病毒JHM株（MHV-JHM），可引发急性脑脊髓炎以及急慢性脱髓鞘疾病，是病毒诱导的神经疾病的重要模型系统。经鼻内感染MHV-JHM的乳鼠C57BL/6，会根据其是否由未免疫或免疫的母鼠哺育，而发展为急性脑脊髓炎或迟发性、有症状的脱髓鞘性脑脊髓炎。通过原位杂交分析来确定MHV-JHM在这些小鼠中进入CNS的途径。早期时，仅在所有小鼠的三叉神经和嗅神经及其直接连接部位检测到病毒RNA。几天后，在死于急性脑脊髓炎的小鼠的整个大脑中发现了MHV-JHM RNA，但在未患急性疾病的小鼠中，病毒RNA仍局限于进入部位。这些结果表明，在所有小鼠中，MHV-JHM均通过神经元间途径进入CNS，但母源抗体的存在可阻止病毒通过细胞外液传播。此外，在未发生急性脑脊髓炎的小鼠中，MHV-JHM可能在三叉神经或嗅神经或其连接部位之一建立低水平持续感染。
