Dropulić B, Masters C L
Department of Pathology, University of Western Australia, Nedlands.
J Infect Dis. 1990 Apr;161(4):685-91. doi: 10.1093/infdis/161.4.685.
Arbovirus infection of cerebral microvascular endothelial cells was investigated in an in vitro mouse brain endothelial (MBE) cell model. Alphaviruses replicated to a greater extent than did flaviviruses, indicating that viremia may be important in neuroinvasion. Also, some viruses (e.g., Semliki Forest virus) replicated to high titers while others (e.g., Murray Valley encephalitis virus) did not. Viruses that replicated to high titers showed luminal polarity of virus release, indicating that infection of the endothelium may be important in both maintenance of viremia and neuroinvasion; viruses that did not so replicate showed abluminal polarity of release, indicating that virus is actively transported across the endothelial monolayer, another mechanism for neuroinvasion. Infection of MBE cells with highly and less-neuroinvasive strains achieved similar results, indicating that the endothelium does not discriminate between neuroinvasive strains. However, the cerebral microvascular endothelium may be important in discriminating between viruses that invade the brain parenchyma and those that do not: neuron-tropic Ross River virus T48 replicated to higher titers than did ependymal-tropic Ross River virus NB5092. Thus, viruses probably use multiple cellular mechanisms to invade the central nervous system across the cerebral microvascular endothelium.
在体外小鼠脑内皮（MBE）细胞模型中研究了虫媒病毒对脑微血管内皮细胞的感染。甲病毒的复制程度高于黄病毒，这表明病毒血症可能在神经侵袭中起重要作用。此外，一些病毒（如Semliki森林病毒）复制到高滴度，而其他病毒（如墨累谷脑炎病毒）则不然。复制到高滴度的病毒显示出病毒释放的管腔极性，这表明内皮细胞感染在维持病毒血症和神经侵袭中可能都很重要；未如此复制的病毒显示出释放的管腔外极性，这表明病毒被主动转运穿过内皮单层，这是神经侵袭的另一种机制。用高神经侵袭性和低神经侵袭性毒株感染MBE细胞获得了相似的结果，这表明内皮细胞不会区分神经侵袭性毒株。然而，脑微血管内皮在区分侵入脑实质的病毒和未侵入脑实质的病毒方面可能很重要：嗜神经性罗斯河病毒T48的复制滴度高于室管膜嗜性罗斯河病毒NB5092。因此，病毒可能利用多种细胞机制穿过脑微血管内皮侵入中枢神经系统。
