Shift of dominant genetic clusters of Japanese encephalitis virus in Kyushu areas.

九州地区乙型脑炎病毒显性基因簇的转变.

• 批准号: 16590477
• 负责人: MAKINO Yoshihiro
• 金额: $ 0.83万
• 依托单位: Oita University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16590477/
• 关键词: Japanese encephalitis virus; Genotype; Phylogenetic tree; Neutralization test; 日本脳炎ウィルス; 遺伝子系統樹; 遺伝子抗体現象; 遺伝型の交代現象

Japanese encephalitis virus (JEV)Japanese encephalitis virus (JEV) has been classified into 4 subtypes (G1-4) based on the molecular phylogenetic analysis of the C-prM gene region (240 base) and the location of isolation. The subtype of Japanese strains was believed to be G3. But, we found that since around 1994, the dominant strain had shifted from G3 to G1, which belonged to the northern Thailand subgroup. It is suggested that these G1 strains might be introduced into Japan from abroad. Phylogenetic analyses based on the C-prM gene region of 23 JEV strains isolated at Nagasaki, Okinawa, Osaka, Ishikawa and Tokyo during 1965-2001 indicated that G3 strains were further divided into 6 clusters (A, B, C, D, E1 and E2), each one of which became dominant during 1935-1994. Antigenic difference among the strains belong to different genetic clusters was examined by 50% plaque-reduction neutralization (NT) test. Six JEV strains and 20 swine sera naturally infected with JEV were used. The results indicated that NT reactivity showed significant difference (P<0.05) (1)between the JEV strains isolated in 1981 and 1989 ; (2)between the strains isolated in 1989 and 1995 ; and (3)between the two strains isolated in 1995. However, NT reactivity was not significantly different between strains isolated in 1981 and 1995. The results indicate that there is a possibility of introduction of antigenically distinct JEV strains into Japan. Continuous JEV surveillance is necessary.

日本脑炎病毒（Japanese encephalitis virus，JEV）根据C-prM基因区（240 bp）的分子系统发育分析和分离地点，将JEV分为4个亚型（G1-4）。日本株的亚型被认为是G3。但从1994年前后开始，优势株由G3转移到G1，属于泰国北方亚群。这些G1菌株可能是从国外传入日本的。对1965-2001年从日本长崎、冲绳、大坂、石川和东京分离的23株JEV的C-prM基因序列进行系统发育分析，结果表明G3株可进一步分为6个簇（A、B、C、D、E1和E2），每一簇在1935 ~ 1994年成为优势株。用50%空斑减少中和试验（NT）检测不同基因簇菌株的抗原性差异。使用6株JEV和20份自然感染JEV的猪血清。结果表明，1981年与1989年分离株、1989年与1995年分离株、1995年与1995年分离株之间的NT反应性差异有显著性（P<0.05）。然而，NT反应性在1981年和1995年分离的菌株之间没有显着差异。结果表明，有一种抗原性不同的JEV株引入日本的可能性。持续的JEV监测是必要的。

项目成果

Shift in Japanese encephalitis virus (JEV) genotype circulating in northern Vietnam: implications for frequent introductions of JEV from Southeast Asia to East Asia

• DOI: 10.1099/vir.0.79797-0
• 发表时间: 2004-06-01
• 期刊: JOURNAL OF GENERAL VIROLOGY
• 影响因子: 3.8
• 作者: Nga, PT;Parquet, MD;Morita, K
• 通讯作者: Morita, K