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。     

重庆市HIV-1样本的亚型分析及G亚型HIV-1毒株在我国的发现

目的 分析重庆市高危人群中HIV-1亚型的流行情况。方法 对采自重庆市经性传播和静脉吸毒途径感染的3份HIV-1阳性外周血分离PBMC,扩增env基因C_2-V_3区核酸片段,并进行核苷酸序列分析。结果 在其中一孕妇体内发现一株G亚型HIV-1毒株序列的存在,这是G亚型HIV-1毒株首次在中国被发现,同时有母婴传播的可能;另外两例被证明为E亚型和C亚型HIV-1毒株。结论 这表明HIV在重庆市高危人群中已有流行并且流行情况复杂。     

山东省HIV-1流行毒株的基因特征和系统树分析

从13名山东省HIV感染者的淋巴细胞(PBMC)中提取前病毒DNA,使用套式PCR方法扩增HIV-lenv基因的C2-V3区。经序列分析发现13份样品均为B′,亚型(泰国B亚型),其与国际参考序列Bcon、泰国代表株93th067A、中国云南省代表株RL42、云南省共享序列96Yn-Bcon的基因离散率分别为7.31％、5.72％、4.25％、3.76％,而远离其它亚型。由系统树可以更清楚看到13个毒株全部与93th067A、RL42等B,亚型流行株聚在一起。通过GCG软件包计算这些毒株彼此间的基因离散率的变异系数为2.71％。以上数据提示HIV-1在山东省的流行时间不长。且与云南省相同亚型的HIV-1毒株密切相关。     

湖北地区人类免疫缺陷病毒-1主要流行株外膜蛋白基因V3-V4区序列变异分析

目的 分析湖北地区HIV-1主要流行株外膜蛋白V3-V4区序列特征,了解其流行特点和变异规律.方法 对湖北地区HIV-1主要流行区域进行流行病学调查,应用套式PCR对102例HIv-1感染者的env基因V3-V4区进行扩增,对阳性扩增样本进行基因测序和序列分析.比较基因距离的差异用卡方检验;基因距离的变异性分析使用描述性分析法.结果 湖北地区共发现4种HIV亚型和重组亚型,其中B'亚型占82.69%,B'/C重组毒株、CRF01_AE重组毒株各占7.69%,C亚型占1.92%.湖北地区HIV-1B'亚型与来源于云南和河南等地的HIV-1B'亚型代表株之间的基因距离分别为7.08±2.19和7.88±2.28.其流行时间约为10年;氨基酸序列变异分析显示,HIV-1B'亚型毒株env基因V3、C3、V4区域均发生不同程度变异,其中以V4区的变异程度最大,V3环顶端四肽表现为GPGR、GPGK、GPGQ和GQGR,分别占46.5%、30.2%、13.6%和9.3%;V3环辅助受体预测显示,其中16.28%为CCR5型,13.95%为CXCR4型,69.77%无法预测;糖基化位点分析显示.湖北地区HIV-1主要流行株env V3-V4区9个糖基化位点有8个存在不同程度丢失.结论 B'亚型仍是湖北地区HIV优势流行株,与来源于云南和河南等地的毒株有较高同源性.     

武汉市HIV-1相关基因序列分析及亚型分布

目的研究武汉市HIV感染人群中的HIV毒株的亚型分布特点和流行规律。方法采集武汉市60名已被确认为HIV-1感染者的抗凝全血样品,提取前病毒DNA,用巢式聚合酶链反应方法（nested-PCR）扩增病毒膜蛋白env基因的C2-V5区及gag基因的部分区段,对PCR纯化产物直接测序,并应用GCG软件对序列进行分析。结果通过PCR扩增得到60份样品的结果,其中env基因序列45份、gag基因序列52份。依据env和gag区基因序列,与HIV-1各个亚型国际参考株比较,通过系统进化分析,最后确定武汉市样品分属5个亚型,分别为HIV-1B亚型中的泰国B（B’）亚型32份,流行重组型CRF07-BC12份,流行重组型CRF01-AE9份,A亚型1份和C亚型6份。结论武汉市存在多种HIV-1亚型,应加强对HIV-1毒株亚型变异的监测,及时调整防治策略。     

出入境人群HIV-1型env C2-V3区段基因序列分析和亚型研究

目的 了解出入境人群艾滋病病毒Ⅰ型(HIV-1)感染者毒株基因亚型分布及流行特征.方法 收集2001年以来上海口岸HIV抗体检测确认阳性的血样标本,提取前病毒DNA,使用套式聚合酶链反应进行体外扩增,获得包膜蛋白区基因(env)的核酸片段,测定其序列和进行亚型分析.结果 获得20例标本的亚型分析结果,共检出8个亚型,包括B亚型7例,CRF02-AG 3例,C亚型3例,CRF01-AE 2例,A亚型2例,B、CRF07-BC和CRF08-BC亚型各1例.上海口岸HIV-1毒株亚型分布于11个国家和地区,主要流行B亚型.结论 上海口岸流行的HIV-1毒株复杂多样,出入境人员是我国HIV毒株输入的主要渠道,流行毒株以性接触传播为主.     

中国首例HIV-1 J亚型毒株的鉴定

目的通过对1例来自刚果的人类免疫缺陷病毒Ⅰ型（HIV-1）感染者样品进行序列分析，鉴定其亚型种类。方法从该感染者血浆样品中提取RNA，经逆转录后采用套式PCR扩增HIV env、gag及pol基因的部分区段，PCR产物直接测序，将所获序列与参考序列进行比对分析，计算基因距离及构建系统进化树。结果该感染毒株样品序列与HIV-1J亚型国际参考株J．SE．93及J．SE．94聚在一起，与两参考株序列在env基因区距离均为8．2％，pol基因区距离分别为6．4％和6．3％，gag基因区距离分别为8．9％和8．0％，证实其为HIV-1J亚型。这是国内首次报道检出HIV-1J亚型。结论HIV-1J亚型毒株已随国际旅行者传人我国，加强对国际旅行人员中HIV毒株亚型的监测具有重要意义。     

九江市HIV-1流行毒株基因序列测定和亚型分析

目的了解九江市艾滋病病毒1型(HIV-1)流行毒株的亚型分布情况。方法对采集的6份九江市HIV-1感染者的血浆样品进行RT-PCR扩增,获得gag基因的核酸片断进行核苷酸序列分析。结果在6份样品中发现B’亚型HIV-1毒株4株,B亚型和A/E重组亚型HIV-1毒株各1株。结论HIV-1流行毒株亚型在九江市分布情况复杂,防控形势严峻。     

广西西部地区吸毒人群HIV-1毒株基因序列测定和亚型分析

目的了解吸毒人群HIV-1流行毒株的亚型类型和变异特征，为艾滋病的疫苗预防、诊治提供依据。方法采集血清和外周血单个核细胞，用ELISA法检测HIV-1的抗体；PEIA检测HIV-1血清亚型；PCR扩增HIV-1膜蛋白基因片段，荧光标记未端终止物循环测序法进行测序反应，自动DNA序列分析仪测定产物序列。结果HIV-1毒株至少有C、E两个亚型。C为优势亚型，其株间基因离散率最大为2．93％，与A亚型等其他9个亚型参考株相比较，基因离散率为12．42～19．05％，gp120 V3环多肽序列相似。还可能存在其它亚型或混合感染。结论吸毒人群HIV-1流行毒株亚型呈现多样性，应加强对HIV-1亚型及其变异的监测和研究，指导疫苗预防、诊断和治疗。     

北京市同性恋HIV-1感染者的包膜基因C2-V3区序列测定和亚型分析

目的 了解北京市同性恋HIV-1感染者HIV-1的亚型类型及传播来源和流行时间。方法 应用套式聚合酶链式反应（PCR）对12份1993～2001年北京市HIV-1阳性同性恋者外周血单个核细胞（PBMC）的核酸样品进行扩增,并对其包膜区的C2-V3段的306个核酸序列进行测定和分析。结果12份样品全部是B亚型的HIV-1毒株序列,其亚型内的基因离散率为 10.35± 2.06,与国际 A-E亚型共享序列比较后发现其与 A、C、D、E亚型的共享序列的基因离散率均大于 25％,而与国际 B亚型共享序列的基因离散率仅为11.25±3.60。系统树分析显示,12个毒株与B亚型共享序列聚在一起并远离其它国际亚型,并且12个毒株与SF162紧密相连,而与国际B亚型共享序列和泰国B亚型代表株TH14可以分开。对gp120中最重要的中和抗体决定簇V3环序列进行对比分析发现,12毒株在V3环中变化较大,其中4毒株带有GPGR这一欧美B亚型V3环顶端四肽序列特征,占33.33％,1个毒株带有GLGR,占8.33％,而其它7个毒株为GWGR,占58.34％。结论HIV-1在北京市同性恋人群中流行的为B亚型,流行来源为欧美,流行时间10年左右,V3环顶端四肽序列特征以GWGR为主。     

Genetic similarity of HIV type 1 subtype E in a recent outbreak among injecting drug users in northern Vietnam to strains in Guangxi Province of southern China.

To investigate the molecular epidemiology of a recent HIV-1 outbreak in northern Vietnam and its relation to the epidemic in surrounding areas, we analyzed 17 HIV-positive blood specimens from 3 heterosexuals, 2 sexually transmitted disease patients, and 12 injecting drug users (IDUs), collected in 4 provinces near Hanoi in 1998. These were compared with the specimens from Ho Chi Minh City (n = 10) and An Giang Province (n = 10) in southern Vietnam and with published sequences from neighboring countries. Genetic subtyping based on the env C2/V3 sequences revealed that HIV-1 subtype E predominated throughout Vietnam in all risk populations; the exception was one typical United States-European-type HIV-1 subtype B detected in a patient in Ho Chi Minh City, the first case of HIV infection identified in Vietnam in 1990. The HIV-1 subtype E sequences identified in 9 of the 12 IDUs from northern provinces were closely related phylogenetically to those in IDUs in nearby Guangxi Province of China, and also shared a common amino acid signature downstream of the env V3 loop region. The low interperson nucleotide diversity among IDUs in northern Vietnam supports the view that HIV-1 subtype E was introduced recently among IDUs in northern Vietnam. These data indicate a linkage between HIV-1 circulating among IDUs in northern Vietnam and southern China, and suggest recent transborder introductions as the likely source of HIV-1 subtype E in northern Vietnam.     

Genotypic subtyping of the HIV-1 polymerase gene in 30 naåve patients from Thailand

To investigate the subtype classification of the circulating virus strains among infected Thai patients with human immunodeficiency virus type 1 (HIV-1). A random population of patients who were HIV-1 antibody positive after two independent screening assays was selected. HIV RNA from plasma samples was reverse-transcribed and amplified with specific primers that annealed to conserve regions of the HIV-1 pol gene. Amplified products were sequenced directly by using an automated sequencer. The sequencing products represent about 1.2 kb of the pol gene from each patient and they were phylogenetically analyzed and compared to the corresponding pol sequences of the published HIV-1 sequences of known genotypes. Genotype E was found in 25 of 30 patients (83.3%), and 5 patients (16.7%) were HIV-1 genotype B. The result confirmed that HIV-1 subtype E is still predominant in Thailand. Genotype B is found frequently, but there have been no examples of genotype A. In concordance with the serotypic assay, which was previously reported using the V3-peptide enzyme immunoassay (V3-PEIA), the genotypic assay of subtype E was high, at 80% and 83.3% in serotyping and genotyping, respectively. These findings of two subtypes with low heterogeneity indicate that Thailand may be a desirable site for evaluating candidate HIV-1 antiretroviral drugs and vaccines. The mixture of subtype E and B' strains also offers the opportunity to study phenotypic differences between the two subtypes.     

福建省HIV-1流行毒株序列测定与亚型分析

使用PCR技术对 19份福建省HIV - 1阳性感染者或病人的外周血淋巴细胞 (PBMCs)进行扩增 ,获得HIV - 1膜蛋白 (env)基因的部分核酸片段 ,并对其V3及邻区～ 30 0个核酸序列进行测定及分析。结果表明 ,19份样品中 11份为E亚型 ,5份为B亚型 ,1份为A亚型 ,1份为C亚型。上述资料表明 ,到目前为止流行于福建省的HIV - 1毒株的特点为以E、B亚型为主 ,多种亚型并存。两者型内以及与国际标准亚型序列的基因离散率均比较大。与其他省份的比较表明我省的毒株的传入与其他省份没有相关     

Phylogenetic analysis of env, gag, and tat genes of HIV type 1 detected among the injecting drug users in West Bengal, India

A recent occurrence of HIV-1 seropositivity among a group of injecting drug users (IDUs) in Darjeeling, a hilly district in northern West Bengal, revealed overall 11.8% HIV seroprevalence. Our study based on env (C2-V3), gag (p24-p7), and tat (exon-1) genomic regions of HIV-1 detected among this population showed that Darjeeling IDU sequences belonged to subtype C. Interestingly, the IDU sequences from Darjeeling were again found to be closer to the C strains from Manipur, a northeastern state in India, which is linked to the Golden Triangle via the Manipur-Myanmar border, rather than the IDU C sequences from Nepal, a neighboring country of India. The outgroup reference strains from different sites of IDU-driven epidemics in the world like Russia, Vietnam, Thailand, and Spain belonged to the nonsubtype C group and formed separate clusters from the subtype C cluster in our analysis. These results indicate a rapid spread of HIV-1 by possible drug trafficking along international boundaries, which might also help in the invasion of HIV-1 among IDUs of Darjeeling through the Manipur-Myanmar border of India.     

深圳市HIV—1B亚型感染毒株env基因序列测定和分析

应用巢式-PCR方法,对深圳检出的2份HIV-1感染者的外周血单核细胞样本进行扩增,获得HIV-1膜蛋白(env)基因核酸片段,并对其C_2-V_3区及邻区350～450个核苷酸序列进行测定和分析.结果表明这2份血样为HIV-1B亚型毒株感染(sz-B),彼此间的基因离散率为10.2%;与A-E国际参考亚型序列比较,sz-B与A及C-E参考亚型共享序列间的基因离散率均大于22%,而与欧美B亚型(Boon)间的基因离散率仅为7.5%;与国内部分地区流行的B亚型代表株比较其基因离散率为11%～12%.提示HIV-1B亚型在深圳的流行时间约为10年,主要经性途径由境外传入,且经性传播途径在人群中流行.     

Genetic evidence of multiple transmissions of HIV type 1 subtype F within Romania from adult blood donors to children

We studied the phylogeny of HIV-1 subtype F viruses from children and adults in Romania in order to (1) clarify whether the Romanian subtype F epidemic was caused by one or several virus introductions and (2) gain insight into the route of spread of the HIV-1 subtype F virus among children and adults in Romania. env (V3), gag (p17/half p24), and pol (prot/half RT) sequences were obtained from three districts in Romania: Tirgu Mures (n = 9, children), Craiova (n = 15, children), and Bucharest (n = 13, adults). Of 37 HIV V3 sequences from Romania, 35 belonged to the genetic subtype F in the neighbor-joining tree, whereas 2 sequences from adults clustered with subtypes A and C. Within the subtype F cluster, no bootstrap-supported subclusters were observed according to geographic area in Romania. Two of the adult V3 sequences that clustered with the children were obtained from individuals who tested HIV seropositive in 1989 and 1990, showing that the subtype F virus was present among adults when the HIV epidemic began among children in Romania. The HIV-1 subtype F viruses obtained from children showed a mean pairwise V3 nucleotide distance of 7.9% and maximum distances of between 18 and 19%; both are higher than previously described. The mean V3 distances (overall, synonymous, and nonsynonymous) were significantly higher for adults than for children. One V3 sequence from the Democratic Republic of Congo clustered within the Romanian sequences, suggesting that the subtype F virus in Romania may originate from this area. Our data also suggest that HIV-1 subtype F was present among Romanian adults before it appeared in 1989 among institutionalized children. The juvenile population was most likely infected with the HIV-1 subtype F virus on more than one occasion, presumably through HIV-contaminated blood (products) obtained from adults.     

Genetic characterization of incident HIV type 1 subtype E and B strains from a prospective cohort of injecting drug users in Bangkok, Thailand

We obtained specimens from 128 HIV-1 seroconverters identified from 1995 through 1998 in a prospective cohort study of 1,209 HIV-negative injecting drug users (IDUs) in Bangkok, Thailand. Epidemiologic data indicated that parenteral transmission accounted for nearly all infections. HIV-1 DNA from the C2-V4 env region was sequenced, and phylogenetic analyses determined that 102 (79.7%) of the specimens were subtype E and 26 (20.3%) subtype B strains. All subtype B strains clustered with strains often referred to in previous studies as Thai B or B'. The interstrain nucleotide distance (C2-V4) within subtype E strains was low (mean, 6.8%), and pairwise comparisons with a prototype subtype E strain, CM244, showed limited divergence (mean, 5.6%). The subtype B stains showed greater interstrain divergence (mean, 9.2%) and were significantly divergent from the prototype B strain HIV-MN (mean, 13.0%; p < 0.0001). The subtype E strains had significantly lower mean V3 loop charge than did subtype B strains (p = 0.017) and, on the basis of analysis of amino acid sequences, were predicted to be predominantly (91%) non-syncytium-inducing (NSI), chemokine coreceptor CCR5-using (CCR5+) viruses. The subtype B strains had a higher mean V3 loop charge, and a smaller proportion (23%) were predicted to be NSI/CCR5+ viruses. This study demonstrates that most incident HIV1 infections among Bangkok IDUs are due to subtype E viruses, with a narrow spectrum of genetic diversity. The characterization of incident HIV-1 strains from 1995 to 1998 will provide important baseline information for comparison with any breakthrough infections that occur among IDUs in Bangkok who are participating in an HIV-1 vaccine efficacy trial initiated in 1999.     

Genetic characterization of CRF01_AE full-length human immunodeficiency virus type 1 sequences from Fujian, China

HIV-1 CRF01_AE is the main prevalent HIV-1 recombinant strain in China and the dominant strain in Fujian as well; therefore, obtaining and understanding the genetic characterization of this clade become important. To date only a few full-length HIV-1 CRF01_AE genomes from China have been sequenced. We reported 13 full-length HIV-1 CRF01_AE isolate sequences from Fujian, China. DNA was extracted, the 5' and 3' halves of each genome were separately amplified, and the PCR products were cloned and sequenced. The phylogenetic analysis of the 13 sequences showed that they clustered with HIV-1 CRF01_AE isolates; these isolates were separated into a few distinct subgroups and were dispersed among the Thailand isolates, and the intersample diversity among Fujian isolates was significantly high. The high gene diversity among Fujian HIV-1 CRF01_AE isolates indicates that the HIV-1 CRF01_AE viruses in Fujian may be transmitted from multiple introductions. The work is essential for the design and development of an effective AIDS vaccine for China.