利用流行性乙型脑炎病毒减毒株脑细胞吸附特征快速筛选减毒株的初步研究

QUlCH SELECTION OF ATTENUATED STRAINSOF JAPANESE ENCEPHALITIS (JE ) VIRUS BY THEIRADSORBENT CHARACTER TO CEREBRAL CELLS

实验证明,流行性乙型脑炎病毒减毒株的脑细胞吸附能力明显低于强毒株。据此,我们发展建立了一种从强毒SA14株中快速、简便地筛选减毒株的新方法。将3周鼠脑细胞37℃吸附SA14株1小时,从未吸附的病毒颗粒中挑出3个减毒株(C4、C5和B1)。将C5株再次吸附筛选,得到C563株。C563株已完全丧失对3周鼠的脑内毒力和皮下毒力,免疫小鼠一针即能诱导良好的抗体反应和保护力,经BHK21细胞盲传5代或乳鼠脑传一代,毒力没有明显回升。

It had been reported that the adsorbent ability to cerebral cells of attenuated JE virus strains was much lower than that of virulent strains. Based on this character of the attenuated strains, we developed a new quick and convenient method to select attenuated mutants from virulent JE virus SAl4 strain. After adsorption of SAl4 strain with cerebral cells of 3-week-old Swiss mice at 37℃ for 1 hr, 3 attenuated mutants ( C4, C5 and B1 ) were selected from the nonadsorbed supernatant. C563 strain was obtained by another cycle of adsorption of the C5 mutant.C563 strain had completely lost its virulence after incerebral and subcutaneous injection of 3-week-old Swiss mice, could induce good immune response and protective effect in mice and was stable after five passages in BHK21 cells or one passage in the brain of suckling mice.