山东省某些高危人群HIV-1感染者分子流行病学研究

目的 了解流行于山东境内ＨＩＶ－１毒株的亚型分布及变异情况,分析其来源并推测其流行趋势。方法 采集了２５份ＨＩＶ－１抗体阳性感染者的全血分离单核细胞（ＰＢＭＣ）,提取前病毒ＤＮＡ,经ｎｅｓｔｅｄ－ＰＣＲ扩增ＨＩＶ－１膜蛋白（ｅｎｖ）基因的Ｃ２－Ｖ３区并进行序列测定和亚型分析。结果 ２５例ＨＩＶ－１阳性感染者的ＰＢＭＣ样品中扩增到２４份可用于序列测定的ＨＩＶ－１ｅｎｖ基因片段,经序列测定和基因分析鉴     

中国人类免疫缺陷病毒（HIV—1）D亚型毒株gag,env和t …

目的 通过对ＨＩＶ－１毒株ｇａｇ,ｔａｔ,ｅｎｖ基因的序列分析,阐明Ｄ亚型ＨＩＶ－１毒株已在中国出现。方法 从１名四川非洲回国营务人员ＨＩＶ感染者（ＳＣ９ ７１２）淋巴细胞（ＰＢＭＣ）中提取前病毒ＤＮＡ,使用套式ＰＣＲ方法分别扩增ＨＩＶ－１的ｇａｇ基因区,ｅｎｖ基因的Ｃ２Ｖ３区和ｔａｔ基因的第一外显子。结果 发现ＳＣ９ ７１２在ｇａｇ区,ｅｎｖ区和ｔａｔ区与国际标准Ｄ亚型毒株的基因距离最近,其中在     

云南省陇川县HIV—1流行毒株膜蛋白基因C2—V3区序列测定…

使用ＰＣＲ对２１份采集于１９９５年中的云南陇川县ＨＩＶ－１阳性静脉吸毒者外周血单个核细胞（ＰＢＭＣｓ）样品进行扩增，从１７份样品中获得了ＨＩＶ－１膜蛋白（ｅｎｖ）基因的核酸片段，并对其Ｃ２－Ｖ３及邻区４５０个核苷酸序列进行了测定和分析。研究结果表明，１７份陇川样品中存在Ｂ和Ｃ两种亚型的ＨＩＶ－１毒株序列，各亚型内的基因离散率分别为４．７％和３．３％。与Ａ￣Ｅ参考亚型及部位Ｂ和Ｃ亚型代表株序列相比较     

云南省陇川县HIV-1流行毒株膜蛋白基因C2-V3区序列测定和分析

使用ＰＣＲ对２１份采集于１９９５年中的云南陇川县ＨＩＶ－１阳性静脉吸毒者外周血单个核细胞（ＰＢＭＣｓ）样品进行扩增，从１７份样品中获得了ＨＩＶ－１膜蛋白（ｅｎｖ）基因的核酸片段，并对其Ｃ２－Ｖ３及邻区４５０个核苷酸序列进行了测定和分析。研究结果表明，１７份陇川样品中存在Ｂ和Ｃ两种亚型的ＨＩＶ－１毒株序列，各亚型内的基因离散率分别为４．７％和３．３％。与Ａ～Ｅ参考亚型及部分Ｂ和Ｃ亚型代表株序列相比较，属陇川Ｂ亚型的１４个毒株与包括泰国、缅甸及云南瑞丽在内的Ｂ亚型毒株序列十分接近，基因离散率在３．９％～４．５％的范围内；属陇川Ｃ亚型的３个毒株则与代表印度毒株的Ｃ亚型共享序列及瑞丽Ｃ亚型毒株序列十分相似，其基因离散率均为２．５％。以上数据提示，ＨＩＶ－１在陇川的流行时间不长，且Ｂ和Ｃ亚型毒株的传入时间相差１年左右。对Ｂ亚型毒株Ｖ３环序列的分析还发现，位于Ｖ３环顶端的四肽序列中ＧＰＧＱ占６４．３％，ＧＰＧＲ则仅占２８．６％，且编码其精氨酸（Ｒ）的密码子均为ＣＧＡ而不是ＡＧＡ。此结果与作者根据早期瑞丽ＨＩＶ－１毒株序列研究结果得出的推测相吻合。     

深圳市HIV-1 E亚型感染毒株的分子流行病学分析

目的 了解人类免疫缺陷病毒１型Ｅ亚型毒株在深圳市不同人群中流行传播情况、流行时间和传播规律。方法 应用聚合酶链反应（ＰＣＲ）方法对１９９６年深圳市检出的３份人类免疫缺陷病毒１型（ＨＩＶ－１）感染者外周血单个核细胞样本进行扩增,获得ＨＩＶ－１膜蛋白（ｅｎｖ）基因片段,并对Ｃ２－Ｖ３及其邻区３５０～４５０个核苷酸序列进行测定和分析。结果 这３份血样为ＨＩＶ－１Ｅ亚型毒株感染（ｓｚ－Ｅ）,彼此间的基因离散率为２．６％;与Ａ－Ｅ国际参考亚型及国内部分地区流行的ＢＥ型代表株比较,ｓｚ－Ｅ与Ａ－Ｄ参考亚型共享序列及国内Ｂ亚型代表株间的基因离散率均大于２４％,而与主要代表泰国Ｅ亚型（Ｅｃｏｎ）间的基因离散率仅为６．２％。系统树分析显示,ｓｚ－Ｅ与Ｅｃｏｎ聚集在一起,远离其他国际亚型毒株序列。结论 ＨＩＶ－１Ｅ亚型在深圳的流行     

我国西南西北地区吸毒人群重组人类免疫缺陷病毒1？…

目的 寻找人类免疫缺陷病毒１型在中国可能的重组。方法从流行２种以上ＨＩＶ－１亚型的地区收集ＨＩＶ感染者的血样。从ＰＭＣｓ中应用套式聚合酶链反应方法,对ＨＩＶ病毒的ｔａｔ和ｅｎｖ基因进行扩增,ＰＣＲ产物直接测序并进行序列分析。结果 对中国Ｂ’亚型和Ｃ亚型浒区域收集的１４个ＨＩＶ－１毒株进行序列分析,对ｅｎｖ基因进行测序后没有发现重组毒株的证据。     

我国西南西北地区吸毒人群重组人类免疫缺陷病毒1型毒株的发现

目的寻找人类免疫缺陷病毒１型（ＨＩＶ１型）在中国可能的重组。方法从流行２种以上ＨＩＶ１亚型的地区收集ＨＩＶ感染者的血样。从ＰＭＣｓ中应用套式聚合酶链反应（ＰＣＲ）方法,对ＨＩＶ病毒的ｔａｔ和ｅｎｖ基因进行扩增,ＰＣＲ产物直接测序并进行序列分析。结果对中国Ｂ′亚型和Ｃ亚型流行区域收集的１４个ＨＩＶ１毒株进行序列分析,对ｅｎｖ基因进行测序后没有发现重组毒株的证据。对ｔａｔ基因的第一外显子进行序列分析时,１４个样品中的１０个样品发现了Ｂ′亚型和Ｃ亚型重组的ＨＩＶ１毒株。此外,四川省静脉吸毒者中发现了３个非重组的Ｂ′亚型毒株和１个非重组的Ｃ亚型毒株。结论首次在中国西南部的四川省和西部的新疆维吾尔自治区发现了Ｂ′亚型和Ｃ型的重组ＨＩＶ１毒株。相同的序列和重组方式,表明重组毒株具有相同的起源,同时表明这两个艾滋病流行区域密切相关。由于在新疆只发现了重组毒株,而在四川省则发现了Ｂ亚型、Ｃ亚型和Ｂ′／Ｃ重组毒株,重组很有可能发生在四川而不是新疆。     

人类免疫缺陷病毒1型云南株外膜蛋白原核表达克隆的构建

目的为研究我国云南１型人类免疫缺陷病毒（Ｈｕｍａｎｉｍｍｕｎｏｄｅｆｉｃｉｅｎｃｙｖｉｒｕｓｔｙｐｅ１，ＨＩＶ－１）流行株外膜蛋白（ｇｐ１２０）的有关抗原表位。方法采用套式聚合酶链式反应，以来自云南流行区ＨＩＶ－１感染者的外周血单核巨噬细胞基因组为模板，进行云南流行株外膜蛋白基因（ｅｎｖ）片段的扩增，并将ｅｎｖ基因片段与原核表达载体ｐＢＶ２２０进行重组，构建成质粒ｐＹＮｅｎｖ并在大肠杆菌（Ｅ．ｃｏｌｉＤＨ１０ｂ）中获得表达。采用限制性内切酶分析进行重组质粒的鉴定。结果含重组质粒的宿主菌经３０℃２０小时培养后，转入４２℃培养５小时，经ＳＤＳ－ＰＡＧＥ蛋白电泳分析有重组蛋白的表达。经Ｗｅｓｔｅｒｎｂｌｏｔ反应证实，该重组蛋白可与来自该流行区的ＨＩＶ－１感染者血清（含多克隆抗体）发生特异反应。结论该重组膜蛋白可作为抗原用于ＨＩＶ－１膜蛋白抗体的检测，并为进一步研究ＨＩＶ－１ｇｐ１２０的病理机制奠定了基础。     

1990～1997年云南IDUsHIV—1B亚型分离株膜蛋白V3环 …

目的 观察云南静脉药瘾（ＩＤＵｓ）ＨＩＶ－１分离株ｅｎｖ基因Ｖ３环顶端四肽氨基酸和相应核苷酸序列随时间推移的变化。方法 根据１９９０～１９７年间６２株ＨＩＶ－１分离株ｅｎｖ基因Ｃ２－Ｖ３区ＤＮＡ序列，对ＨＩＶ－１膜蛋白Ｖ３环顶端四肽基因序列（基序）及其编码核苷酸进行分析，并探讨其随时间推移的变化趋势。结果 １９９０～１９９７年间６２株ＨＩＶ－１毒株膜蛋白Ｖ３环顶端四肽基序有程度不同的氨基酸变异，主     

人免疫缺陷病毒1（HIV—1）膜蛋白基因片段在酵母中的克 …

目的 为获得足够量的膜糖蛋白，以便于对不同ＨＩＶ分离株膜糖蛋白的结构与功能进一步的研究。方法 从人免疫缺陷病毒１（ＨＩＶ－１）ＨＸＢ２分离株原病毒基因组的重组质粒ｐＨＸＢ２中克隆了两段膜糖蛋白基因（ＥＮＶ）片段。以酵母穿梭诱导表达质粒ｐＹＥＳ２为载体。构建了两个相应的重组表达质粒ｐＹＥＮＶ１和ｐＹＥＮＶ２；进一步利用大肠杆菌β－半乳糖苷酶基因（β－ｌａｃＺ）构建了ＨＩＶ－１膜外糖蛋白ＤＮＡ片段与β     

Development of an env gp41-based heteroduplex mobility assay for rapid human immunodeficiency virus type 1 subtyping

The gp120 region of the human immunodeficiency virus type 1 (HIV-1) envelope (env) gene exhibits a high level of genetic heterogeneity across the group M subtypes. The heteroduplex mobility assay (HMA) has successfully been used to assign subtype classifications, but C2V5 primers often fail to amplify African strains. We developed an env gp41-based HMA for which the target sequence is amplified with highly conserved gp41 primers, known to efficiently amplify nucleic acids from HIV-1 group M, N, and O viruses. By using gp41 from a new panel of reference strains, the subtype assignments made by our modified HMA were concordant with those obtained by sequencing and phylogenetic analysis of 34 field strains from 10 countries representing subtypes A to G. Testing of field strains from Nigeria further demonstrated the utility of this modified assay. Of 28 samples, all could be amplified with gp41 primers but only 17 (60.7%) could be amplified with the standard C2V5 primers. Therefore, gp41-based HMA can be a useful tool for the rapid monitoring of prevalent subtypes in countries with divergent strains of circulating HIV-1.     

Determination of human immunodeficiency virus type 1 subtypes in Taiwan by vpu gene analysis

The genetic diversity of human immunodeficiency virus (HIV) type 1 (HIV-1) has been characterized mainly by analysis of the env and gag genes. Information on the vpu genes in the HIV sequence database is very limited. In the present study, the nucleotide sequences of the vpu genes were analyzed, and the genetic subtypes determined by analysis of the vpu gene were compared with those previously determined by analysis of the gag and env genes. The vpu genes were amplified by nested PCR of proviral DNA extracted from 363 HIV-1-infected individuals and were sequenced directly by use of the PCR products. HIV-1 subtypes were determined by sequence alignment and phylogenetic analysis with reference strains. The strains in all except one of the samples analyzed could be classified as subtype A, B, C, E, or G. The vpu subtype of one strain could not be determined. Of the strains analyzed, genetic subtypes of 247 (68.0%) were also determined by analysis of the env or gag gene. The genetic subtypes determined by vpu gene analysis were, in general, consistent with those determined by gag and/or env gene analysis except for those for two AG recombinant strains. All the strains that clustered with a Thailand subtype E strain in the vpu phylogenetic analyses were subtype E by env gene analysis and subtype A by gag gene analysis. In summary, our genetic typing revealed that subtype B strains, which constituted 73.8% of all strains analyzed, were most prevalent in Taiwan. While subtype E strains constituted about one-quarter of the viruses, they were prevalent at a higher proportion in the group infected by heterosexual transmission. Genetic analysis of vpu may provide an alternate method for determination of HIV-1 subtypes for most of the strains, excluding those in which intersubtype recombination has occurred.     

A gag gene heteroduplex mobility assay for subtyping HIV-1

A heteroduplex mobility assay (HMA) using 753 and 446 base pair (bp) amplicons of the p17/p24 region of the gag gene of HIV-1 has been developed and validated with reference clones and clinical samples representative of subtypes A, B, C, D, E, G, and H. There was complete concordance between the gag HMA assigned subtype and the subtype known from gag or env sequence data or env HMA. The heteroduplexes from both amplicons can be clearly resolved on either MetaPhor XR agarose or MDE polyacrylamide gels. The MetaPhor XR gel system was the more convenient and is the preferred choice for routine HMA subtyping. This gag HMA provides a rapid, simple and inexpensive method for subtyping HIV-1 based on a genomic region other than the commonly used env gene target. The incorporation of gag HMA into subtype determination algorithms should allow the detection of gag/env recombinant strains of HIV-1.     

Study of HIV-1 subtypes in serodiscordant couples attending an integrated counselling and testing centre in Mumbai using heteroduplex mobility analysis and DNA sequencing

Aims: To determine the prevalent subtypes of HIV-1 in serodiscordant couples. Setting: Integrated Counselling and Testing Centre (ICTC), Department of Microbiology. Study Design: Prospective pilot study. Participants: Thirty HIV-1 serodiscordant couples. Inclusion Criteria: a) Documentation of HIV-1 infection in one partner and seronegative status in the other, current history of continued unprotected sexual activity within the partnership, demonstration that they have been in a partnership for at least 1 year and are not currently on highly active antiretroviral therapy HAART; b) willingness of both partners to provide written informed consent including consent to continued couple counselling for 3 months. Materials and Methods: HIV-1 subtyping was carried out by heteroduplex mobility analysis (HMA) by amplifying env region; and DNA sequencing by amplifying gag region. Results: HIV-1 env gene was amplified successfully in 10/30 samples; gag gene, in 25/30 samples; and both env and gag gene were amplified successfully in 5/30 samples. HIV-1 subtype C was detected from 21 samples; subtype B, from 7; and subtype A, from 2. Sample from 1 positive partner was detected as subtype C by env HMA and subtype B by gag sequencing. Conclusion: HIV-1 subtype C was found to be the predominant subtype of HIV-1 in serodiscordant couples attending our ICTC, followed by HIV-1 subtype B and HIV-1 subtype A, respectively. DNA sequencing was found to be the most reliable method for determining the subtypes of HIV-1.     

HIV-1 diversity in Brazil: genetic, biologic, and immunologic characterization of HIV-1 strains in three potential HIV vaccine evaluation sites. Brazilian Network for HIV Isolation and Characterization

The Brazilian Network for HIV Isolation and Characterization was established for the surveillance of HIV variability in Brazil. Here, we report characterization of HIV strains and virus-specific immune responses from 35 clinical samples collected from three potential HIV vaccine sites. Three genetic subtypes of HIV-1 were identified by heteroduplex mobility assay (HMA) B (in 82.9% of the samples), F (14.3%), and C (2.9%). Phylogenetic analysis based on the C2V3/env DNA sequence from all 25 specimens examined was 100% concordant with HMA results. Four variants of subtype B with different tetrapeptides at the tip of the V3 loop were found: the GPGR motif (North American), GWGR motif (Brazilian B"), and two minor variants, GFGR and GPGS, as previously detected. No significant association was found between HIV-1 subtypes and the mode of transmission or biologic properties of HIV-1 isolates (derived from 88.6% of the specimens). Only 5 of 16 isolates studied were neutralized by the autologous sera. Consistent with previous results, no relation between viral subtype and peptide enzyme-linked immunosorbent assay (ELISA) seroreactivity or neutralization was evident. This study also demonstrated the effectiveness of the collaborative approach followed by Brazilian scientists when addressing a complex subject such as HIV variability.     

Molecular epidemiology of vertical human immunodeficiency virus type 1 transmission in Greece: evidence of non-B subtypes

OBJECTIVES: To investigate the subtype classification of the circulating virus strains among human immunodeficiency virus type 1 (HIV-1)-infected children in Greece. STUDY DESIGN/METHODS: Since the beginning of the acquired immunodeficiency syndrome (AIDS) epidemic in Greece in 1982, 23 children have been reported to be vertically infected with HIV-1. Blood samples were available for 19 of these children, and the C2-C4 env region was successfully amplified by nested polymerase chain reaction (PCR) for 16 subjects. HIV-1 subtype was established by the heteroduplex mobility assay (HMA) in 16 subjects and confirmed by DNA sequencing and phylogenetic analysis in 8 subjects. RESULTS: Most subjects (9; 56%) fell into subtype B. However, a substantial proportion (44%) were classified as subtypes A (3; 19%), C (1; 6%), D (1; 6%), and I (2; 12%). According to epidemiologic information, 5 of 7 children infected with non-B HIV-1 subtypes were born to Greek parents. CONCLUSION: These findings clearly suggest that non-B strains have been introduced into Greece, providing evidence that HIV epidemic in this country will probably change profile over time. In addition, subtype I was identified in 2 HIV-1-infected children, both of whom were born to Greek parents.     

Discrimination of subtype B and non-subtype B strains of human immunodeficiency virus type 1 by serotyping: correlation with genotyping

The ability of a peptide-based serotyping assay to differentiate human immunodeficiency virus (HIV) type 1 (HIV-1) subtype B infections from non-subtype B infections was investigated with 166 anti-HIV-1- and HIV RNA-positive (by PCR) serum or plasma specimens. The specimens were divided genetically into those infected with subtype B and non-subtype B by application of a screening heteroduplex mobility assay (HMA) that used plasmids for subtypes A and B alone. Specimens that were not clearly infected with HIV-1 subtype B by HMA or for which the two methods had discordant results in distinguishing those infected with subtype B from those infected with non-subtype B were then investigated with a full HMA plasmid panel and, for selected specimens, env sequencing. For the 141 genotyped and serotypically reactive specimens, the correlation between genotyping and serotyping (all subtypes) was 69%. Of the 67 specimens that reacted monotypically as serotype B, 64 were shown to be infected with genotype B (positive predictive value, 96%). Of the 82 specimens that contained genotype B nucleic acid, 64 reacted monotypically as serotype B (sensitivity, 78%), and 4 specimens reacted with a single non-subtype B peptide; the viruses in 14 specimens could not be assigned a serotype. Initial screening results had indicated that 12 samples had results discordant between restricted HMA and serotyping. The V3 loop amino acids of the infecting HIV strains from the seven specimens with discordant serology results were analyzed. For five specimens discordance occurred when the amino acid sequence of the infecting virus closely resembled those of more than one consensus peptide antigen or when the observed V3 crown motif of the strain was atypical for the genetic subtype present. For the other two specimens no explanation for the discordance was identified. Five specimens gave unclear or discordant results in the initial HMA screen, but the results were resolved when the full plasmid panel was used. Serotyping, although of limited sensitivity, distinguishes between subtype B and non-subtype B infections with a high degree of specificity. However, it poorly differentiates the major non-subtype B subtypes, particularly subtypes A and C. When HIV-1 subtype B predominates, serological typing and/or subtype-restricted HMA screening usefully distinguishes between subtype B and non-subtype B infections.