辽宁省乙脑病毒的分离与鉴定

目的 对2002年辽宁省采集的蚊虫标本进行病毒分离与鉴定。方法 从辽宁省采集蚊虫标本4927只，用细胞培养的方法分离病毒，对新分离的病毒进行血清学（ELISA和IFA方法）、分子生物学鉴定。结果 本实验共研磨蚊虫标本50批，分离到2株病毒，命名为LN02-102、LN02，104。这2株病毒均可致BHK-21细胞病变（CPE）（2—3d），致Vero细胞病变（2—4d），也可致C6／36细胞病变（2—4d）。对3日龄乳鼠2—3d可致死。这2株病毒可与标准乙脑病毒抗体反应。利用病毒PrM区段（基因组456-695核苷酸）进行基因分型分析。新分离的2株病毒属于基因Ⅰ型乙脑病毒。对这2株病毒的E基因区段进行分析，它们之间核苷酸和氨基酸的同源性为100％，与疫苗株SA14-14-2相比，核苷酸差异为4．11％，氨基酸差异在0．60％。结论 在辽宁省采集的蚊虫标本中分离到2株病毒，经血清学和分子生物学鉴定为基因Ⅰ型乙脑病毒，是近年来在辽宁省首次分离到基因Ⅰ型的乙脑病毒。

Isolation and Identification of Japanese encephalitis virus in Liaoning Province

BACKGROUND: To study arboviruses carried by mosquitoes in Liaoning Province in 2002. METHODS: Totally 4927 mosquitoes were collected from Liaoning Province in July 2002. Virus strains were isolated by inoculating BHK-21, C6/36 and Vero cells. The newly isolated strains were identified by serological (ELISA and IFA) and molecular methods (Real-Time PCR and RT-PCR). RESULTS: Two strains were isolated from mosquitoes causing cytopathogenic effect (CPE) on cells and were fatal to suckling mice. Serological tests showed that both were positive for the antibody to JEV. The PrM and E gene were cloned and sequenced. The phylogenetic analysis showed that the new isolates belonged to genotype I, JEV. Sequence analysis showed that the homology of nucleotide sequences and amino acid (AA) sequences between the two strains was 100%. Compared with the nucleotide sequences between the two strains and the standard JEV vaccine strain SA14-14-2, the difference was up to 4.11%, and the difference of AA was 0.6%. CONCLUSION: Two strains of JEV were isolated and identified in Liaoning province, both belonged to genotype I JEV.