Saechan Vannarat, Mori Atsumi, Mitarnun Winyou, Settheetham-Ishida Wannapa, Ishida Takafumi
Unit of Human Biology and Genetics, Department of Biological Sciences, Graduate, School of Science, University of Tokyo, Tokyo, Japan.
J Clin Virol. 2006 Jun;36(2):119-25. doi: 10.1016/j.jcv.2006.01.018. Epub 2006 Apr 17.
The latent membrane protein 1 (LMP1) of Epstein-Barr virus (EBV) has sequence heterogeneity. Some of the variants are associated with altered tumorigenic activity and show geographically specific localization. In Thailand, the EBV genome is frequently detected in circulating T cells of T-cell diseases.
To determine the role of EBV LMP1 variation in the genesis of T-cell diseases, we focused on virus factors and analyzed EBV strains in Thailand.
EBV DNA was extracted from 18 healthy individuals and 45 patients with T-cell diseases in Southern Thailand and 30 healthy individuals in Central Thailand. By using PCR-direct sequencing method, nucleotide sequences corresponding to the carboxyl terminus of the LMP1 were determined.
Four known strains, B95-8 prototype, China 1, China 2 and Mediterranean (Med) and two novel strains, Southeast Asia 1 (SEA 1) and Southeast Asia 2 (SEA 2) were identified. The prevalence of China 2 strain was significantly different (p=0.006) between Central and Southern Thailand. Higher prevalence (p=0.026) of 30-bp deletion type in the Southern Thais was observed. The LMP1 Med strain was associated with the worse prognosis (p=0.029). Among T-cell diseases patients, CD3(+)-cell oriented infection was recognized in SEA1 strain (p=0.025).
The distribution of EBV strains may be associated with geographic/ethnic and clinical background in the Thai population. Certain EBV strains defined by their LMP1 sequence may influence cell tropism, disease association, or disease severity.
爱泼斯坦-巴尔病毒（EBV）的潜伏膜蛋白1（LMP1）具有序列异质性。一些变体与致瘤活性改变有关，并显示出地理特异性定位。在泰国，EBV基因组在T细胞疾病的循环T细胞中经常被检测到。
为了确定EBV LMP1变异在T细胞疾病发生中的作用，我们聚焦于病毒因素并分析了泰国的EBV毒株。
从泰国南部的18名健康个体和45例T细胞疾病患者以及泰国中部的30名健康个体中提取EBV DNA。采用PCR直接测序法，测定与LMP1羧基末端相对应的核苷酸序列。
鉴定出四种已知毒株，即B95-8原型株、中国1株、中国2株和地中海（Med）株，以及两种新型毒株，即东南亚1（SEA 1）株和东南亚2（SEA 2）株。中国2株在泰国中部和南部的流行率有显著差异（p = 0.006）。在泰国南部人群中观察到30 bp缺失型的流行率较高（p = 0.026）。LMP1 Med株与较差的预后相关（p = 0.029）。在T细胞疾病患者中，SEA1株表现出以CD3(+)细胞为主的感染（p = 0.025）。
EBV毒株的分布可能与泰国人群的地理/种族和临床背景有关。某些由其LMP1序列定义的EBV毒株可能影响细胞嗜性、疾病关联或疾病严重程度。
