摘要： 为研究猪乙脑病毒(JEV)分离株遗传基因的稳定性,将JEV分离株BSF.ZZ-1和BSF.ZZ-3在BHK-21细胞上进行连续传代培养,并对其E基因的遗传稳定性进行了研究。结果表明,经连续传代60次后病毒E基因趋于稳定,BSF.ZZ-1毒株E蛋白氨基酸位点E21(A→V)、E200(T→A)、E244(G→E)、E279(M→K)和E426(G→D),以及BSF.ZZ-3毒株的E244(G→E)、E255(F→L)、E285(M→L)、E368(L→S)和E497(N→S)传代后发生稳定点突变。与JEV毒力相关的部分位点如E107、E138、E176、E177和E315遗传稳定性较高,经连续传代后均未发生突变,与疫苗株SA14-14-2相应位点完全一致。但是,另外一些位点的遗传稳定性较差,如BSF.ZZ-3的E279(M→K→M)出现反复突变。这些突变是否与JEV的宿主细胞适应性及毒力变化相关有待进一步研究。

关键词: 乙脑病毒, BSF.ZZ-1, BSF.ZZ-3, BHK-21细胞系, 传代培养, E基因, 序列分析

Abstract: In this paper, the genetic stability of E gene of JEV isolates BSF.ZZ-1 and BSF.ZZ-3 passaged in BHK-21 cells(Baby hamster kidney cell line ) was studied.The results showed that the E gene is becoming stable after 60 passages in BHK-21 cells.After serial sucultivation,stable amino acid(aa) mutation happened at the sites E21(F→L),E200(T→A),E244(G→E),E279(N→S) and E426(G→D) in isolate BSF.ZZ-1 and sites E244 (G→E),E255(F→L),E285(M→L),E368(L→S) and E97(N→S) in isolate BSF.ZZ-3.No mutations were ob-served at part of the virulence correlated aa sites, such as E107,E138,E176,E177 and E315,similar to those of vaccine strain SA14-14-2.However,mutations at the virulence correlated aa sites of E279(M→K→M)of BSF.ZZ-3 happened repeatedly.Whether these mutations are correlated with the virulence variation and adaptability of JEV to host cells needs to be further studied.

Key words: JEV, BSF.ZZ-1, BSF.ZZ-3, BHK-21 cell line, SeRial subcultivation, E gene, Sequence analysis

中图分类号: 

• S852.65