一种简易的HIV-1病毒载量定量筛查方法的建立

目的 建立一种基于RT-PCR法的简易的HIV-1感染者或艾滋病患者血浆病毒载量筛查方法.方法 在广西南宁市采集18例HIV-1感染者和18例阴性对照者血液标本,提取RNA,以引物LTR-1/LTR-2对待测样本进行PCR扩增,获得Ct值.同时,应用Nuclisens EasyQ HIV-1 v1.2法作为对照对这些样本进行病毒载量检测.对Ct值与病毒载量之间进行相关性分析,获得相应的回归方程.结果 待测样本中HIV-1感染者Ct值在29.103～31.610个循环之间,阴性对照者未能扩增出产物.RT-PCR法Ct值与Nuclisens EasyQ HIV-1 v1.2法检测出的病毒载量对数值之间具有良好的线性关系（r=-0.51,P=0.03）,回归方程为logY（viral road）=57.55-1.56＆#215;（Ct value）.结论 所建立的HIV-1病毒载量RT-PCR检测方法操作简单,价格便宜,与商业化试剂盒具有较好的一致性,可用于HIV-1感染定量筛查.     

CCR5△32、CCR5m303、CCR2-64I、SDF1-3''A基因多态性对中国HIV-1感染者预后的影响

目的研究CCR5A32、CCR5m303、CCR2-64I、SDF1—3’A基因多态性对中国HIV-1感染者预后的影响。方法对在深圳地区发现的HIV-1感染者进行流行病学调查，应用PCR／RFLP技术分析感染者CCR5G32、CCR5m303、CCR2-64I、SDF1-3’A4种基因的多态性，对部分人群进行HIV-1血浆病毒载量和CD4^＋细胞计数的检测，判断感染者的潜伏期，使用SPSS11．0统计软件分析基因多态性对感染者病毒载量和潜伏期的影响。结果在189例HIV-1感染者中没有发现CCR5A32和CCR5-m303突变基因型，SDF1—3’A的等位基因频率为26．14％，CCR2—64I的等位基因频率为19．82％。方差分析发现，CCR2-64I基因野生型与杂合型的两组HIV-1感染者人群病毒载量对数的大小差异无统计学意义（P=0．272），两组人群潜伏期的长短差异无统计学意义（P=0．662）。SDF1基因野牛型、杂合型和纯合型的3组HIV-1感染者人群病毒载量对数的大小差异有统计学意义（P=0．001），但3组人群潜伏期的长短差异无统计学意义（P=0．228）。结论CCR2-64I基因突变对中国汉族HIV-1感染者病毒载量没有明显影响，因而也不影响感染者的潜伏期。SDF1-3’A基因突变对于病毒载量有降低作用，但对延长感染者潜伏期可能没有作用。     

我国主要HIV-1流行株耐药基因型检测方法的研究

目的研究针对中国主要HIV-1流行株优化的实验室自建耐药基因型实验室自建检测方法（in—house）的扩增效果及检测敏感度。方法选取中国主要流行亚型的B、CRF07-BC、CRF01-AE亚型各10份样本,这些样本为2007—2009年本实验室采集采自河南、新疆、湖南三地已接受抗病毒治疗患者的样本,并已确定亚型。选用生物梅里埃公司的NuclisensEasyQ方法对选取的30份样本的病毒载量平行进行3次病毒载量检测,取平均值作为载量数值。对每份样本用HIV阴性血浆进行5个浓度的梯度稀释,稀释为〉1000、401～1000、101～400、50～100和〈50拷贝／ml5个浓度梯度。提取核酸后,进行RT—PCR和巢式PCR扩增,对扩增结果进行统计扩增结果,确定每种亚型的扩增效果和最低检测限。随机选取12份样本的初浓度和最低浓度进行测序,对测序结果进行耐药结果分析和序列一致性分析。结果所选样本的病毒载量介于2．03×102～5．92×104拷贝／ml之间。自建的In—house法对载量50—1000拷贝／ml范围的样本仍可达到较高的扩增效果（86％）。样本稀释前后耐药位点相似,序列一致性在97％以上,在低病毒载量时优势病毒株的检测则更敏感。结论自建的实验室方法的灵敏度较高,对低病毒载量水平的样本仍有较高的扩增效果。     

我国主要HIV-1流行株耐药基因型检测方法的研究

目的 研究针对中国主要HIV-1流行株优化的实验室自建耐药基因型实验室自建检测方法( in-house)的扩增效果及检测敏感度.方法 选取中国主要流行亚型的B、CRF07 _BC、CRF01_AE亚型各10份样本,这些样本为2007 -2009年本实验室采集采自河南、新疆、湖南三地已接受抗病毒治疗患者的样本,并已确定亚型.选用生物梅里埃公司的Nuclisens Easy Q方法对选取的30份样本的病毒载量平行进行3次病毒载量检测,取平均值作为载量数值.对每份样本用HIV阴性血浆进行5个浓度的梯度稀释,稀释为＞ 1000、401～1000、101 ～400、50 ～100和＜50拷贝/ml 5个浓度梯度.提取核酸后,进行RT-PCR和巢式PCR扩增,对扩增结果进行统计扩增结果,确定每种亚型的扩增效果和最低检测限.随机选取12份样本的初浓度和最低浓度进行测序,对测序结果进行耐药结果分析和序列一致性分析.结果 所选样本的病毒载量介于2.03×102 ～5.92×104拷贝/ml之间.自建的In-house法对载量50 ～1000拷贝/ml范围的样本仍可达到较高的扩增效果(86％).样本稀释前后耐药位点相似,序列一致性在97％以上,在低病毒载量时优势病毒株的检测则更敏感.结论 自建的实验室方法的灵敏度较高,对低病毒载量水平的样本仍有较高的扩增效果.     

宁夏回族自治区HIV-1感染者抗病毒治疗前免疫学与病毒学指标调查

目的了解该地区部分HIV．1感染者抗病毒治疗前CD4^＋T淋巴细胞、病毒载量分布及耐药性毒株存在情况。方法利用流式细胞技术对CD4^＋T淋巴细胞计数，使用NASBA方法测定病毒载量，利用lit-PCR获得目的基因序列，登陆http：／／hivdb．stanford．edu分析耐药突变位点。结果该地区感染人群中66．66％的患者CD4^＋T淋巴细胞数〉350个／mm^3，患者病毒载量对数平均值为3．784±1．048，检测样本中有2例出现耐药性。结论该地区HIV-1感染者目前多为无症状期，但病毒拷贝数较高，耐药性毒株流行水平较低。应在该地区加强抗病毒治疗的宣传。     

慢性HIV-1感染人群血浆不同中和能力及与有关因素的研究

目的 探讨安徽省既往献血的HIV慢性感染人群血浆中和能力及其与CD4、病毒载量的关系.方法 从安徽省既往献血的294位HIV慢性感染人群静脉抽血,EDTA抗凝后进行血浆和外周血单个核细胞(PBMC)的分离、CD4和病毒载量的检测,采用拥有共享序列的临床分离病毒1597株和实验室株SF33病毒两种病毒分别做血浆的中和试验.用200TCID50病毒感染TZM-bl细胞,通过加入不同稀释度血浆,用Luciferase Assay System检测血浆的中和能力并计算中和50%的病毒进入细胞的血浆浓度(EC50).结果 294位患者血浆针对HIV-1实验株SF33和临床分离株1597的中和能力间差异有统计学意义(P<0.05),针对实验株的中和能力明显高于临床分离株,91%患者血浆对HIV-1实验株SF33具有一定的中和抗体,其中EC50>500的抗体水平较高的血浆占33%,对临床分离株1597的中和抗体阳性率为79%,其中EC50>500的占7%.方差分析显示,血浆中和能力在CIM不同水平之间没有显著差异.294位HIV-1B'亚型感染的血浆病毒载量(1g)平均为4.40(2.60～6.46).方差分析显示,血浆对SF33的中和能力在不同病毒载量水平之间有显著差异,病毒载量不同的各组血浆针对1597病毒的中和能力之间差异无统计学意义.经Spearman's B相关分析,对SF33株的中和水平与病毒载量呈正相关,对1597株的中和水平与病毒载量的相关性没有统计学意义.在病毒载量1g<4的患者中,10.53%血浆样品的EC50高于500;在病毒载量1g≥5的患者中,6.46%血浆样品的EC50高于500.结论 HIV-1慢性感染人群的血浆对实验株SF33的中和能力随着病毒复制能力的提高而增加,但对临床分离株1597的中和能力未见相关性.     

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。     

基于qPCR的两种试剂在HIV-1病毒载量检测中的比较研究

目的比较两种实时荧光定量PCR试剂检测HIV-1病毒载量间的相关性和一致性, 以及性能参数。方法两种检测试剂各采用3个批号对系列稀释的定值质控品检测, 分析两种检测试剂的检测线性度和精密度。再用两种试剂对166例HIV抗体阳性样品和27例阴性样品分别进行检测, 比较两者的相关性和一致性。结果 TaqMan病毒载量检测试剂与系列浓度定值质控品检测结果的决定系数为R2=0.978, Xpert病毒载量检测试剂与系列浓度定值质控品检测结果的决定系数为R2=0.987;对不同浓度定值质控品检测结果的不同批号间和总变异系数均<7%。两种试剂不同批号检测定值质控品的结果差异无统计学意义。两种试剂对血浆样本检测结果显示, 对阴性样品检测的符合率为100%, 在40 cps/mL的临界值处的观察一致性为50%, 在其量化下限附近缺乏一致性, 线性范围内检测结果之间的决定系数为R2=0.946。Bland-Altman分析显示, 偏差均值为0.41 log10(IU/mL)。结论两种试剂检测性能均良好, 在HIV-1病毒载量检测中具有较好的临床等效性。     

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。     

中国人群HIV-1B亚型Nef蛋白特异性细胞毒性T细胞反应的研究

目的探讨中国人群HIV-1B亚型Nef蛋白特异性细胞毒性T细胞(CTL)反应特征及其与病毒载量以及CD4细胞数量间的关系。方法选取33例HIV-1B亚型感染者。用合成的HIV-1B亚型Nef全基因序列肽库作为抗原,ELISPOT方法检测HIV-1B亚型Nef蛋白特异性CTL反应,同时测定病毒载量及CD4细胞数量。结果70％的感染者对Nef产生特异性CTL反应,单一肽段能够被识别的频率不超过40％,应答强度为(1102±2136)SFC(斑点形成细胞数)／106 PBMC。HIV-1B亚型Nef特异性CTL应答的强度和频率之间没有显著的相关性。HIV-1 Neff特异性CTL反应强度与病毒载量间存在显著负相关,与CD4细胞数量间存在显著正相关。结论初步确定了Nef蛋白CTL应答的优势区域。这些区域主要集中在一些高度保守的氨基酸序列。提示HIV-1B亚型Nef特异性CTL应答在疾病进展中对机体具有保护性作用。     

Impact of HIV-1 genetic diversity in China on the measurement of viral load

In this study, 190 HIV-positive samples were collected from different regions of China. The HIV clades of 153 samples were determined successfully based on env sequencing. Specifically, 48, 5, 87, and 13 isolates belonged to clades B', B, BC, and AE, respectively. The viral loads in all samples were measured using three commercial assays, Amplicor HIV-1 monitor v1.5, Nuclisens HIV-1 QT and NucliSens EasyQ HIV-1 assays. The differences and linear correlations for individual assays were compared, with expected 1:1 relationships. Significant differences were found for the following viral loads: clade BC measured by any two assays (P < 0.001); clade AE between Amplicor 1.5 and Easy Q (P = 0.005); clade B' between Amplicor 1.5 and Nuclisens QT (P = 0.002); clade AE between Amplicor 1.5 and Nuclisens QT (P = 0.025); and clade B' between Amplicor 1.5 and EasyQ (P = 0.04). The largest mean difference in the log(10) values was 0.9518, which was found between Amplicor 1.5 and Nuclisens QT. However, the viral loads for clades AE and B' measured by EasyQ and Nuclisens QT, and those for clade B measured by any two assays did not differ significantly. The degrees of correlation for clades B and B' between any two assays (R > 0.8) were higher that those for clades AE and BC between any two assays (R < 0.7), except for clade AE between Amplicor 1.5 and Easy Q. Thus, the clade types, especially clades BC and AE, are most likely to impact on the quantitation of viral load using differentassays.     

Evaluation of NucliSens EasyQ HIV-1 assay for quantification of HIV-1 subtypes prevalent in South-east Asia.

BACKGROUND: Monitoring anti-retroviral therapy requires that viral load assays for human immunodeficiency virus type 1 (HIV-1) be applicable to diverse HIV-1 subtypes. OBJECTIVES: To evaluate NucliSens EasyQ HIV-1 assay for quantitation of common HIV-1 subtypes prevalent in South-east Asia. STUDY DESIGN: One hundred and nineteen plasma samples collected in Hong Kong and Cambodia were used to compare the performance of NucliSens EasyQ HIV-1 and COBAS Amplicor HIV-1 Monitor version 1.5 assays. Viral RNA extracted from the NucliSens MiniMAG was also used for HIV-1 subtyping. RESULTS: Performance of NucliSens EasyQ correlated well with COBAS Amplicor (r=0.777, p<0.001) and the small mean difference (0.0462log(10)IU/mL) obtained in the Bland and Altman model indicated good agreement between two assays. The NucliSens EasyQ assay demonstrated a 95% sensitivity at 500IU/mL and 100% specificity. Reproducibility of this assay was within log(10)2-4IU/mL and had a coefficient of variation between 2.3% and 10.4%. Among the 109 specimens included in the analysis, HIV-1 subtyping identified 64 CRF01_AE, 38 subtype B, 3 subtype C, 3 CRF07_BC and 1 subtype G viruses. CONCLUSIONS: Performance of NucliSens EasyQ was comparable to COBAS Amplicor for HIV-1 viral load monitoring. RNA extracts from NucliSens MiniMAG could be used for HIV-1 viral load monitoring, subtyping and drug resistance mutations detection. Our findings highlight the versatility of both NucliSens EasyQ and COBAS Amplicor in monitoring prevalent subtypes and rare circulating recombinant forms (CRFs) in the South-east Asia region.     

Underevaluation of HIV-1 plasma viral load by a commercially available assay in a cluster of patients infected with HIV-1 A/G circulating recombinant form (CRF02)

The authors studied the correlation and agreement of commercially available assays in detection and quantification of the HIV-1 intersubtype A/G circulating recombinant form CRF02. The assays under comparison were Bayer Versant HIV-1 RNA, version 3.0; Roche Amplicor HIV-1 Monitor, version 1.5 (standard procedure); and Organon Teknika NucliSens HIV-1 RNA QT. Plasma samples from 114 patients infected with CRF02 were tested by the three assays under standard conditions. Although correlation among the assays was high and statistically significant for subtype B and CRF02, in the latter instance, NucliSens measured average viral load values (3.29 +/- 0.71 log(10) copies/mL) about 4 and >8 times lower than those obtained by Versant (3.90 +/- 0.90 log(10) copies/mL) and Amplicor (4.22 +/- 1.05 log(10) copies/mL), respectively. Furthermore, in a statistically significant percentage of CRF02-harboring samples, NucliSens produced viral load values undetectable or 1 log(10) lower than those obtained in Versant and Amplicor assays. Altogether, these data underline a low performance of NucliSens in detecting and quantifying viremia in plasma samples harboring the CRF02. These results are potentially important as global distribution of new HIV-1 subtypes is expanding, and recombinant strains, particularly CRF02, are emerging and becoming highly prevalent.     

Significant differences between plasma HIV-1 RNA assays in HIV-1 subtype E infected patients treated with antiretroviral therapy

A total of 72 HIV-1 infected Thai patients treated with didanosine (ddI) or stavudine (d4T) plus ddI at the time of interim analysis were analyzed. Sixty patients (83%) carried subtype E documented by HIV-1 V3 serotyping. HIV-1 RNA levels were measured using three commercial viral load assays. At baseline (n = 57), Quantiplex 2.0 and NucliSens 2.0 showed mean log10 HIV-1 RNA of 0.7 log10 or 5 fold lower than Amplicor 1.5 (mean 4.29 versus 5.0 log10, respectively, p < 0.001). At week 20 of treatment (n = 29), HIV-1 RNA levels were detected in 55.2%, 31%, and 33.5% of subjects tested by Amplicor 1.5, Quantiplex 2.0, and NucliSens 2.0, respectively. In conclusion: plasma HIV-1 RNA analyses showed comparable values with Quantiplex 2.0 and NucliSens 2.0 assays. In contrast, Amplicor 1.5 resulted in approximately 5 folds higher HIV-1 RNA levels and a 25% higher rate of detection of plasma HIV-1 RNA as compared to the other two assays. As the current goal of therapy is to suppress plasma viral load below the detection limit of the assays, the significant differences between the assays may influence antiretroviral efficacy evaluation and management.     

Comparative performance of the Amplicor HIV-1 Monitor Assay versus NucliSens EasyQ in HIV subtype C-infected patients

In facing global programs for treating HIV-infected patients in the developing countries, there is a real need for viral load assays that are accurate for the local subtypes. The present study was designed to evaluate viral load measurements using the newer version of the NASBA assay in subtype C-infected patients. The performances of this new version, a real-time nucleic acid sequence-based amplification HIV-1 assay (NucliSens EasyQ), were compared to Amplicor HIV-1 Monitor Assay version 1.5 in 79 samples of subtype C-infected patients originating from Ethiopia. Twenty HIV-1 subtype B-infected patients served as a control group. Blood samples from patients in both groups were tested by both assays. The results were compared by a paired, two-tailed Student's t-test. The disparity between the results of the two viral load assays was highly significant in subtype C samples (P = 0.005), such that in the vast majority, higher values of viral load were obtained by the Amplicor assay. However, no differences between the two assays were found in subtype B samples (P = 0.77). CD4 measurements were available for 78 samples of subtype C-infected patients. Of these, a CD4-to-viral load discrepancy (CD4 相似文献   

Measurement of HIV RNA in patients infected by subtype C by assays optimized for subtype B results in an underestimation of the viral load

Quantitation assays of HIV-1 RNA used currently were designed and optimized for subtype B viruses. However, infection with non-B HIV viruses has become more common worldwide. Unfortunately, little information is available regarding the suitability of these assays for measurement of viral load in specific non-B subtypes. The performance of two commercial HIV-1 RNA quantitation assays was evaluated in 82 HIV subtype C-infected patients and in 43 HIV-1 subtype B-infected patients. Blood samples were tested by the Amplicor HIV-1 Monitor Assay, Version 1.5, and by the nucleic acid sequence-based amplification HIV-1 assay (NucliSens). The results were compared by using a paired, two-tailed Student's t-test; the difference between the assays was found to be significant only for subtype C. Discordant results (>0.5 log difference) between the two assays were detected in 39% of subtype C samples, compared to 23.2% of subtype B samples. In all cases in which a discordant result was detected, the lower results were obtained by the NucliSens assay. Discordant results between CD4 and viral load (CD4 < 200 cells/ml with a viral load <5,000 copies/ml) were observed in eight of the subtype C-infected patients when a viral load was measured by NucliSens (9.7%), compared to three patients (3.6%) when measured by the Amplicor assay. In conclusion, in patients with HIV subtype C infection, measurement of HIV RNA by the NucliSens assay resulted in a significant underestimation of the viral load as compared to the Amplicor assay. As a consequence, such an underestimation may result in sub-optimal care of patients infected with HIV subtype C.     

Evaluation of the NucliSens EasyQ assay in HIV-1-infected individuals in South Africa

We compared the performance of the NucliSens EasyQ assay (bioMerieux) combined with the manual NucliSens miniMag extraction methodology to the Roche Cobas Ampliprep/Standard Amplicor Monitor methodology (Roche Diagnostics) for HIV-1 RNA quantitation in HIV-1-infected individuals in South Africa. Plasma samples (284) from HIV sero-positive patients at different stages of infection were analyzed. The distribution of results was typical of the clinical samples received at the laboratory where 20% have viral load results <400 copies/ml (2.6 log) and 18% have viral load results >750000 copies/ml (5.8 log) using the Roche Amplicor Monitor standard assay. All statistical analyses were performed using log10-transformed values for all the variables in the analyses, i.e. log10EasyQIU/ml, and log10RNA (log10 copies/ml, Amplicor). Roche values were converted from RNA copies per ml to IU/ml by multiplying the Roche value by 0.51. HIV RNA levels quantitated by the NucliSens EasyQ assay correlated significantly with those of the Roche Cobas Amplicor Monitor assay (r=0.874, p<0.0001). Reproducibility of the NucliSens EasyQ assay in the log6IU range yielded CV variance of 1.3-2.84% for two well-trained technologists. In addition, a retrospective evaluation of the performance of the NucliSens EasyQ assay in 102 runs (2448) samples was conducted in the laboratory over a 4-month interval. Factors considered during this evaluation included time taken to perform the assay, volume requirements, number of required repeats, potential for contamination.