广西HIV-1重组毒株env区快速基因分型方法的建立

目的建立一种快速简便的基因分型方法，对广西HIV-1重组毒株env基因区进行亚型鉴定。方法从HIV阳性样品中提取核酸，使用HIV-1M组通用引物对env区进行第一轮扩增，第二轮则使用分别检测B′/C或C亚型和CRF01-AE亚型的二套特异性引物放入同一反应管中进行扩增，根据不同亚型扩增的目的带位置不同来判断亚型。将通用引物扩增出的所有样本均进行基因测序和系统树分析以验证结果。结果50份样本中，经基因测序和系统树分析证实CRF08-BC样本3份（6％），CRF01-AE样本43份（86％），4份（8％）样本无法确定亚型。经亚型特异性引物PCR法检测得出B′/C或C亚型样本3份（100％），CRF01-AE样本39份（90．7％），灵敏度为91．3％，特异度为100％。两种方法检测结果经差异性检验显示X^2=2．25，P〉0.05，差异无统计学意义，结果一致者占92％。与基因分析结果吻合。重复实验显示CRF08-BC平均重复性为100％（10／10），CRF01．AE为93．8％（61／65）。结论该方法是一种简便、快速、低成本，具有高度灵敏性和特异性的HIV-1毒株env基因区分型法，能够直接对广西HIV-1 CRF01-AE重组毒株进行鉴定。     

我国HIV-1主要流行株外膜蛋白(env)基因V3～V4区变异及其与生物学特性的关系

目的　研究我国HIV 1主要流行毒株亚型的envV3～V4区变异与生物学特性的关系。方法　应用nested PCR对 1 57份获自我国 1 2个省份的HIV 1毒株env区序列进行扩增 ,并使用ABI 377型测序仪测序 ,然后应用BLAST、GCG和MEGA等生物学软件或程序对env基因V3～V4区序列进行分析。结果　B′亚型毒株V3顶端四肽存在着 4种类型 :GPGR ( 54% )、GPGQ ( 2 8% )、GPGK( 1 6 % )和GPGA( 2 % ) ,B′/C重组毒株全部为GPGQ( 1 0 0 % ) ,CRF0 1 AE重组毒株呈现GPGQ( 95% )和GPGR( 5% )两种类型 ;B′/C和CRF0 1 AE重组毒株V3～V4区及其临近区域N 糖基化位点比B′亚型毒株N 糖基化位点保守。而B′亚型毒株V3环的净电荷分别显著高于B′/C和CRF0 1 AE毒株 (P <0 .0 1 ) ;根据V3环关键氨基酸推测辅助受体使用情况的结果显示 :B′亚型毒株有 9.2 6 %可能使用CCR5,7.4 1 %可能使用CXCR4 ,其余 83.33%不能对辅助受体的使用作出预测。所有B′/C重组毒株被预测可能使用CCR5。CRF0 1 AE重组毒株有 90 .4 8%被预测可能使用CCR5,没有被预测为使用CXCR4的序列 ,9.52 %不能作出预测。结论　B′亚型毒株大部分可能为NSI型 ,少部分可能为SI型 ,而B′/C和CRF0 1 AE重组毒株绝大部分为NSI型。我国主要流行株的V3～V4区尤其是V3环的氨基酸     

湖北省HIV-1流行株gag基因序列测定及亚型分析

目的 了解湖北省HIV-1感染者流行毒株亚型分布和流行趋势.方法 随机采集湖北省HIV-1感染者的抗凝全血标本,分离血浆,提取病毒RNA,用套式聚合酶链反应扩增HIV-1病毒gag基因,并进行序列测定和亚型分析.结果 对80份HIV-1感染者的样品进行扩增,得到了62份样品的HIV-1基因片段.共发现7种HIV-1亚型和流行重组株.泰国B'亚型占11.3％ (7/62),欧美B亚型占4.8％ (3/62),G亚型占4.8％ (3/62),CRF07-BC占22.6％ (14/62),CRF08-BC占6.5％(4/62),CRF01-AE占48.4％(30/62),CRF15-01B占1.6％ (1/62).在湖北省发现了CRF15-01B和G亚型.结论 湖北省存在多种HIV-1亚型和流行重组型,CRF01-AE、CRF07-BC两种重组亚型毒株为目前湖北省HIV-1流行优势毒株,应加强对HIV-1毒株亚型变异的监测,及时调整防治策略.     

26例有偿献血员HIV-1基因分型与变异特征

目的分析某地区有偿献血人员中流行的人免疫缺陷病毒1型（HIV-1）gag、pol、env基因亚型及基因变异特征。方法提取HIV-1感染者外周血单核细胞（PBMC）DNA,经巢式PCR（NestedPCR）扩增gag（p17-p24）、pol（PR＊RT）、env（C2-V5）基因片段,纯化测序后用MEGA5．0等生物学软件对核苷酸序列进行分析。结果23份样本为B亚型,2份为B亚型与C亚型重组,1份为CRF01-AE与B亚型重组。PR区未发现蛋白酶抑制剂主要耐药性突变,RT区检测到核苷类逆转录酶抑制剂耐药性突变M184V和非核苷类逆转录酶抑制剂耐药性突变K101E,G190A。结论流行于该地区的HIV-1毒株以B亚型为主。大多数毒株对常规抗病毒药物仍然敏感,使用HARRT治疗方案依然有效。CXCR4型辅助受体的毒株顶端四肽多为GPGR（91．7％）,提示GPGR可能与疾病的进展有关。     

2006年北京市外来人口中HIV-1感染者流行毒株gag基因序列测定和亚型分析

目的了解北京市外来人口中HIV-1亚型的特点和流行规律。方法随机采集北京市2006年外来人口中新确证HIV-1感染者的抗凝全血标本80份，分离血浆，提取病毒RNA，用套式聚合酶链反应扩增病毒gag基因，并进行序列测定和亚型分析。结果系统进化分析确定北京市外来人口HIV-1毒株属于8个亚型，分别为B亚型4份，泰国B亚型15份，C亚型1份，CRF01-AE亚型5份，CRF02-AG亚型1份，CRF07-BC亚型29份，CRF08-BC亚型3份，CRFl5—01B亚型1份。结论北京市外来人口中己存在8种HIV-1亚型和流行重组型，应该加强对HIV-1亚型变异的监测。     

26例有偿献血员HIV-1基因分型与变异特征

目的 分析某地区有偿献血人员中流行的人免疫缺陷病毒1型( HIV-1) gag、pol、env基因亚型及基因变异特征.方法 提取HIV-1感染者外周血单核细胞(PBMC) DNA,经巢式PCR( Nested PCR)扩增gag(p17-p24)、pol( PR-RT)、env(C2-V5)基因片段,纯化测序后用MEGA5.0等生物学软件对核苷酸序列进行分析.结果 23份样本为B亚型,2份为B亚型与C亚型重组,1份为CRF01_AE与B亚型重组.PR区未发现蛋白酶抑制剂主要耐药性突变,RT区检测到核苷类逆转录酶抑制剂耐药性突变M184V和非核苷类逆转录酶抑制剂耐药性突变K101E,G190A.结论 流行于该地区的HIV-1毒株以B亚型为主.大多数毒株对常规抗病毒药物仍然敏感,使用HARRT治疗方案依然有效.CXCR4型辅助受体的毒株顶端四肽多为GPGR(91.7％),提示GPGR可能与疾病的进展有关.     

河北省HIV-1流行株基因序列测定及亚型分析

目的 了解河北省HIV-1流行株的亚型分布和流行趋势.方法 从感染者的血浆样品中提取病毒RNA,逆转录后采用套式PCR扩增HIV-1 gag和env基因的部分片段,对PCR产物直接进行核苷酸序列测定,所获序列与各亚型国际参考株序列比对,确定基因型并进行系统进化树分析.结果 对154份HIV-1感染者的样品进行扩增,得到了148份样品的HIV-1基因片段.发现6种HIV-1亚型和重组型,以及2例未定型.其中B'亚型61例(41.2%)、CRF01_AE 59例(39.9%)、CRF07_BC 16例(10.8%)、CRF08_BC 6例(4.1%)、C亚和B01亚型各2例(1.4%).在河北省首次发现了B01亚型.结论 2009年河北省存在多种HIV-1亚型和流行重组型,主要是B'亚型和CRF01_AE重组型,应加强对HIV-1毒株亚型变异的监测,及时调整防治策略.     

山东省部分HIV-1流行株的亚型分析和序列特征研究

目的　对山东省HIV 1流行毒株进行亚型分析 ,并研究其变异特征。方法　采集 2 6份HIV 1感染者的外周静脉抗凝血 ,提取前病毒DNA进行体外扩增 ,获得包膜蛋白 (env)基因的核酸片段 ,并对其C2 V3及邻区的核苷酸进行测定和分析。结果　基因和氨基酸序列分析表明 ,2 6份标本中存在 4种亚型和重组毒株 (B′、C、A、A/E) ,其中B′ 17株 ,其组内基因距离为 11.6 9± 4 .19。V3环顶端四肽有 6种形式 ,最多的是GPGQ(15株 )、GPGR(6株 )。V3环第 11、2 5位氨基酸出现变异 ,并有 1株呈电荷双阳性。结论　山东省HIV 1流行株亚型较多 ,有重组毒株出现的可能 ,基因发生较大变异 ,HIV 1传播在山东省有加快的趋势。     

广州市吸毒强戒人员HIV-1基因亚型分布的初步研究

目的分析吸毒人群HIV感染者中HIV-1的基因序列特征,初步确定其感染的基因亚型和各亚型的流行趋势。方法在Genbank中查找HIVgag基因的序列,设计巢式PCR引物。从全血中提取样本的基因组DNA,进行巢式PCR,对PCR产物进行琼脂糖凝胶电泳和测序,所获序列与国际参考株序列进行比对,确定基因型或亚型。结果对36例HIV-1感染者样本进行扩增,PCR共检测出29例阳性样本,27例测序成功,其中16例为CRF08-BC重组亚型、7例为CRF07-BC重组亚型、4例为CRF01-AE重组亚型,15例阴性对照均无目的条带。结论在广州吸毒强戒人员HIV-1型中以CRFBC亚型为主,其次为CRF01-AE亚型。应加强对HIV-1毒株亚型的监测,以制定更好的防治策略。     

江西省部分吸毒人群HIV-1分子流行病学调查

目的对江西省吸毒人群进行HIV-1分子流行病学调查研究,了解HIV-1流行情况、亚型种类、毒株来源、变异情况等,为政府部门制定预防控制决策提供技术资料。方法传统流行病学与分子流行病学相结合,对江西省9例吸毒人员进行流行病相关因素分析和基因序列、系统进化分析。结果江西省部分吸毒人群不仅共用注射器,同时伴有不洁性交史。流行毒株主要为HIV-1 CRF01-AE,序列分析表明与越南和我国广西吸毒人群流行毒株相似性较高,与越南株U90087平均基因距离为9.00±2.27。系统进化分析表明,江西省吸毒人群的毒株来源完全一致。结论目前江西省吸毒人群中HIV流行已从局部向全省蔓延,流行毒株为HIV-1CRF01-AE。为阻止蔓延,应加强对吸毒人群和性乱人群的行为干预。     

A genotypic resistance assay for the detection of drug resistance in the human immunodeficiency virus type 1 envelope gene

Since it is not clear yet whether enfuvirtide resistance is restricted to gp41, it was decided to develop a genotypic assay for the detection of drug resistance in the entire human immunodeficiency virus type 1 (HIV-1) env gene. Given the increasing prevalence of HIV-1 non-B subtypes in Europe, it is important to evaluate the performance of the assay on a panel of genetically divergent samples. A panel of 1 laboratory and 10 clinical isolates from 10 patients was tested, all enfuvirtide naive and chosen according to the subtype as determined in the pol region (A, B, C, H, CRF01-AE, CRF02-AG, CRF05-DF, CRF11-cpx and U), while their env sequences belonged to subtypes A, B, C, H, A/G recombinant, B/H recombinant, CRF01-AE, CRF02-AG, CRF05-DF and CRF11-cpx. The detection limits of the gp120 and the gp41 PCRs ranged between 500 and 5000 RNA copies/ml plasma. The highest sensitivity was obtained for the laboratory strain, whereas the detection limit for all patient samples, except for the subtype C sample, was 1000 RNA copies/ml. The numerous insertions and deletions in the gp120 gene, that were often present as quasi-species, necessitated the sequencing of cloned PCR products. The gp41 gene displayed less diversity and less insertions/deletions. Especially, the heptad repeat 1 was highly conserved and none of the enfuvirtide naive samples contained any of the already known enfuvirtide resistance mutations at amino acid positions 36-45. This study demonstrates that the assay is able to genotype genetically diverse HIV-1 strains with a good sensitivity.     

The sequential introduction of HIV-1 subtype B and CRF01AE in Singapore by sexual transmission: accelerated V3 region evolution in a subpopulation of Asian CRF01 viruses

The rapid spread of the human immunodeficiency virus type 1 (HIV-1) circulating recombinant form (CRF) 01AE throughout Asia demonstrates the dynamic nature of emerging epidemics. To further characterize the dissemination of these strains regionally, we sequenced 58 strains from Singapore and found that subtype B and CRF01 were introduced separately, by homosexual and heterosexual transmission, respectively. Protein similarity scores of the Singapore CRF01, as well as all Asian strains, demonstrated a complex distribution of scores in the V3 loop--some strains had very similar V3 loop sequences, while others were highly divergent. Furthermore, we found a strong correlation between the loss of a V3 glycosylation site and the divergent strains. This suggests that loss of this glycosylation site may make the V3 loop more susceptible to immune surveillance. The identification of a rapidly evolving population of CRF01AE variants should be considered when designing new candidate vaccines and when evaluating breakthrough strains from current vaccine trials.     

北京市男男性接触HIV-1感染者膜蛋白基因序列测定及亚型分析

目的 了解北京市男男性接触人群(MSM)中HIV-1的最新流行趋势及膜蛋白V3环序列特征.方法 巢式聚合酶链式反应(n-PER)扩增2007年提取的北京市男男性接触HIV感染者基因组DNA样品,对膜蛋白基因C2-V3区测序,进行病毒亚型及V3环序列特点分析.结果 11例样本中,4例是欧美B亚型,5例是AE重组亚型,1例是BC重组亚型,1例是01B重组亚型.V3环顶端四肽以GPGQ和GPGR为主.结论 北京市男男性接触HIV-1感染者中重组亚型呈蔓延流行趋势.     

Biological and genetic characteristics of HIV infections in Cameroon reveals dual group M and O infections and a correlation between SI-inducing phenotype of the predominant CRF02_AG variant and disease stage

In Yaounde, Cameroon, HIV-1 group-specific V3 serology on 1469 HIV-positive samples collected between 1996 and 2001 revealed that group O infections remained constant around 1% for 6 years. Only one group N sample was identified and 4.3% reacted with group M and O peptides. Although the sensitivity of the group-specific polymerase chain reaction (PCR) in two genomic regions was not optimal, we confirmed, in at least 6 of 49 (12.2%) dual O/M seropositive samples and in 1 of 9 group O samples, dual infection with group O and M viruses (n = 4) or with group O or M virus and an intergroup recombinant virus (n = 3). Partial env (V3-V5) sequences on a subset of 295 samples showed that at least eight subtypes and five circulating recombinant forms (CRFs) of HIV-1 group M co-circulate; more than 60% were CRF02_AG and 11% had discordant subtype/CRF designations between env and gag. Similarly as for subtype B, the proportion of syncytium-inducing strains increased when CD4 counts were low in CRF02_AG-infected patients. The V3-loop charge was significantly lower for non-syncytium-inducing strains than for syncytium-inducing strains but cannot be used as an individual marker to predict phenotype. The two predominant HIV-1 variants in Africa, CRF02_AG and subtype C, thus have different biological characteristics.     

Genetic diversity of HIV type 1 in rural eastern Cameroon

To monitor the presence of genotypic HIV-1 variants circulating in eastern Cameroon, blood samples from 57 HIV-1-infected individuals attending 3 local health centers in the bordering rural villages with Central African Republic (CAR) were collected and analyzed phylogenetically. Out of the 40 HIV-1 strains with positive polymerase chain reaction (PCR) profile for both gag and env-C2V3,12 (30.0%) had discordant subtype or CRF designation: 2 subtype B/A (gag/env), 1 B/CRF01, 2 B/CRF02, 1 CRF01/CRF01.A, 2 CRF11/CRF01, 1 CRF13/A, 1 CRF13/CRF01, 1 CRF13/CRF11, and 1 G/U (unclassified). Twenty-eight strains (70.0%) had concordant subtypes or CRF designation between gag and env: 27 subtype A and 1 F2. Out of the remaining 17HIV-1 strains negative for PCR with the env-C2V3 primers used, 10 (58.8%) had discordant subtype or CRF, and 7 (41.2%) had concordant one based on gag/pol/env-gp41 analysis. Altogether, a high proportion (22/57, 38.6%) of the isolates were found to be recombinant strains. In addition, an emergence of new forms of HIV-1 strains, such as subtype B/A (gag/env), B/CRF01 and B/CRF02, was identified. The epidemiologic pattern of HIV-1 in eastern Cameroon, relatively low and high prevalence of CRF02 and CRF11, respectively, was more closely related to those of CAR and Chad than that of other regions of Cameroon, where CRF02 is the most predominant HIV-1 strain. These findings strongly suggest that this part of Cameroon is a potential hotspot of HIV-1 recombination, with a likelihood of an active generation of new forms of HIV-1 variants, though epidemiologic significance of new HIV-1 forms is unknown.     

使用多重巢式PCR对我国HIV-1主要流行株亚型鉴定方法的建立

目的 建立一套新的亚型鉴定方法，仅仅使用巢式PCR，一次扩增，即可对我国HIV-1主要流行株B、C和CRF01-AE进行亚型鉴定。方法 从HIV阳性样本中提取核酸，使用能覆盖HIV-1型M组gag区的引物进行第一轮扩增，第二轮扩增则使用分别检测B、C、CRF01-AE亚型的三套特异性引物进行扩增，三套引物放在同一个反应管中。反应产物经琼脂糖电泳后观察，不同亚型的位置不同，以此来判断亚型。另外设计一套引物，专门检测我国重组株CRF07-BC和CRF08-BC。所有样品均经过基因测序、系统进化树分析，以进行结果验证。结果 在检测的119份样品中，经基因测序和系统进化树分析证实B亚型样品43份(欧美B11份，泰国B32份)，C、CRF01-AE、A和D亚型样品分别为54份、17份、3份和2份。其中C亚型的样品，有52份属于CRF07-BC和CRF08-BC。而经过上述多重巢式PCR方法检测到的B亚型样品为35份(81．4％)，C亚型46份(85．2％)和CRF01-AE13份(76．5％)。另外，检测CRF07-BC和CRF08-BC重组株的引物特异性地检测到43份(82．7％)样品。上述结果与基因分析结果吻合，各个亚型之间无交叉，一种亚型的特异性引物只对该亚型有反应，而对其他亚型无反应，特异性达到100％。虽然有时会有非特异扩增带，但一般不影响结果判断。结论 我们建立了一套简单快速的H1V-1亚型鉴定方法，不需基因测序，即可检测我国主要流行株B、C、CRF01-AE、CRF07-BC和CRF08-BC。该方法具有高度特异性和敏感性，可以作为初筛方法在我国及其他国家HIV-1实验室推广使用。     

Fifteen years of env C2V3C3 evolution in six individuals infected clonally with human immunodeficiency virus type 1

The study of the evolution of human immunodeficiency virus type 1 (HIV-1) requires blood samples collected longitudinally and data on the approximate time point of infection. Although these requirements were fulfilled in several previous studies, the infectious sources were either unknown or heterogeneous genetically. In the present study, HIV-1 env C2V3C3 (nt 7029-7315) evolution was examined retrospectively in a cohort of hemophiliacs. Compared to other cohorts, the area of interest here was the infection of six hemophiliacs by the same virus strain, that is, the infecting viruses shared an identical genome. As expected, divergence from the founder sequence as well as interpatient divergence of the predominant virus strains increased significantly over time. Based on the V3 nucleotide sequences, CCR5 usage was predicted exclusively throughout the whole period of infection in all patients. Interestingly, common patterns of viral evolution were detected in the patients of the cohort. Four amino acid substitutions within the V3 loop emerged and persisted subsequently in five (positions 305 and 308 of the HXB2 gp120 reference sequence) and six patients (positions 325 and 328 in HXB2 gp120), respectively. These common changes within the V3 loop are likely to be enforced by HIV-1 specific immune response.