A molecular genetic approach to the study of Venezuelan equine encephalitis virus pathogenesis.
A molecular genetic approach to the study of Venezuelan equine encephalitis virus pathogenesis.
复制标题
研究委内瑞拉马脑炎病毒发病机制的分子遗传学方法。
DOI：
10.1007/978-3-7091-9326-6_11
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
Johnston,RE
中科院分区：
文献类型：
--
作者：
Davis,NL;Grieder,FB;Smith,JF;Greenwald,GF;Valenski,ML;Sellon,DC;Charles,PC;Johnston,RE
病毒的发病机制可以描述为一系列步骤，类似于生化途径，其终点是受感染宿主的疾病。不同的病毒功能在每个所需步骤中可能是关键的。我们的遗传学方法是使用委内瑞拉马脑炎病毒（VEE）突变体在不同的步骤阻断描绘的发病过程。VEE强毒株的全长cDNA克隆用作体外诱变的模板以产生减毒的单位点突变体。通过感染性、免疫细胞化学、原位杂交和组织病理学监测分子克隆亲本或突变病毒在小鼠中的传播。毒力强的VEE通过淋巴系统传播，产生病毒血症并在几个内脏器官中复制。当病毒从这些部位被清除时，它开始出现在大脑中，通常是从嗅束开始。E2糖蛋白中的单位点突变似乎在非常早期的步骤中阻断发病机制，并且需要回复突变以扩散到接种部位之外。已经使用三种E2突变证明了组合减毒突变以产生稳定的VEE疫苗株的可行性。
Viral pathogenesis can be described as a series of steps, analogous to a biochemical pathway, whose endpoint is disease of the infected host. Distinct viral functions may be critical at each required step. Our genetic approach is to use Venezuelan equine encephalitis virus (VEE) mutants blocked at different steps to delineate the process of pathogenesis. A full-length cDNA clone of a virulent strain of VEE was used as a template for in vitro mutagenesis to produce attenuated single-site mutants. The spread of molecularly cloned parent or mutant viruses in the mouse was monitored by infectivity, immunocytochemistry, in situ hybridization and histopathology. Virulent VEE spread through the lymphatic system, produced viremia and replicated in several visceral organs. As virus was being cleared from these sites, it began to appear in the brain, frequently beginning in the olfactory tracts. A single-site mutant in the E2 glycoprotein appeared to block pathogenesis at a very early step, and required a reversion mutation to spread beyond the site of inoculation. The feasibility of combining attenuating mutations to produce a stable VEE vaccine strain has been demonstrated using three E2 mutations.