1996～1998年中国流行的E亚型艾滋病病毒1型毒株的分子流行病学研究

目的通过对1996～1998年采集的艾滋病病毒1型(HIV-1)毒株样本的env基因的序列分析,阐明在中国流行的E亚型HIV-1毒株的特点、来源和传播方式。为中国E亚型HIV-1疫苗的研制和应用提供基础资料。方法 从HIV感染者淋巴细胞(PBMC)中提取前病毒DNA.使用嵌套式聚合酶链反应(PCR)方法扩增HIV-1的env基因的C2V5区。PCR产物不经克隆直接测序并使用GCG软件包进行序列分析。结果样品采自1996～1998年中国29个省(自治区,直辖市),总共发现37个E亚型HIV-1感染者。他们中大部分是通过性途径感染(23人,占62.2％);部分在静脉吸毒人群中发现(10人,占27.0％);少数是在职业献血员中发现(4人,占10.8％)。经C2-V3区序列分析发现,大部分中国E亚型HIV-1毒株与泰国株很相近,而与非洲株相差很大。而来自广西壮族自治区的毒株与越南吸毒人群中的流行株U48720相一致;系统树分析结果发现,中国的E亚型HIV-1株与泰国(CM240X、H93TH966)、越南(U48720)的代表株聚在一起。结论 中国E亚型HIV-1毒株目前仅在东南沿海地区流行,涉及静脉吸毒、输供血和性乱等各种人群,通过env区的序列分析发现其主要来源于泰国,部分来源于与中国接壤的越南。

Molecular Epidemioiogical Study of a HIV-1 Strain of subtype E in China between 1996 and 1998

Objective To investigate the characteristics, origin and transmission pattern of the HIV-1 subtype E infection in China.Methods Blood was collected from HIV- 1 infected individuals in China.The DNA from peripheral blood mononuclear cells was used as template for amplification of C2-V5 region of HIV env gene. The genes were sequenced and analyzed together with epidemiologi-cal data. Results A total of 37 people infected with subtype E HIV-1 were found in China between 19% and 1998.The majority of them(23,62.2%)were infected through sexual contacts; some were through injecting drugs(10,27.0% )and a small number(4,10.8% ) through contaminated blood. The geographic location of the sexually transmitted subtype E cases were mainly in the southwest border and southeast coastal regions.There were two clusters of subtype E HIV- 1 strains on the phylogenetic tree.One group made by the subtype E sequences from Guangxi and Jiangxi provinces clustered with the subtype E sequences from Vietnam(U48720), and the other made by sequences from Guangdong,Shengzhen and Fujian clustered with the subtype E sequences of Thailand(CM240) .All the subtype E sequences from China were quite different from the African subtype E strain(CF40). Discussion It is concluded that the subtype E HIV - 1 is mainly circulating in the group of sexual transmission in China.Those subtype E HIV- 1 strains originated from two main directions, one from Thailand to the south east coastal regions(Guangdong, Shengzhen and Fujian), and the other from Vietnam to the southwest border regions.