内蒙古地区乙型肝炎病毒的基因分型及临床意义

为了探讨乙型肝炎病毒在内蒙古地区的基因分型,为本地区乙型肝炎的临床治疗、病情进展和发病机制等方面研究提供有益的实验依据。2013年7月至2014年7月本研究在内蒙古自治区人民医院、内蒙古医科大学第一附属医院、通辽市医院的门诊及住院病例中随机选取已感染乙型肝炎病毒的253例。以荧光定量PCR法检测HBV基因分型和HBV病毒基因载量,Elisa法检测血清标志物HBeAg,全自动生化分析仪检测ALT、AST、TBA、TBIL和ALB。实验发现,内蒙古地区253例患者HBV基因分型结果以B型(49例,19.37%)、C型(188例,74.31%)为主,且C基因型显著多于B基因型(p<0.05);HBeAg阳性率为67.59%,且C基因型HBeAg阳性率高于B基因型;高载量病例中B型占31例(63.27%),而C型占162例(86.17%),C基因型组中HBV DNA载量显著高于B基因型组(p<0.01);B基因型与C基因型TBA、TBIL和ALB结果比较差异无统计学意义(p>0.05),但C基因型的ALT和AST这两项生化指标均显著高于B基因型组(p<0.05)。本研究结果初步说明,内蒙古地区HBV感染以B型和C型为主,尤以C型居多;且C型病毒的复制较活跃,致病力较强,HBV感染者更易转成严重肝病。     

高通量流式荧光微球悬液芯片检测乙肝病毒基因分型

目的:建立HBV基因分型高通量液相芯片检测技术,并探讨其应用价值.方法:对GenBank中收录的明确分型的HBV基因序列进行分析,选择preS2-S区设计引物和A、B、C和D型特异性探针.与荧光编码微球偶联的特异型探针与一条引物生物素标记的PCR产物直接杂交反应,然后结合亲和素标记的藻红蛋白,用流式检测仪(Bio-Plex 200)检测荧光信号.检测182份阳性乙肝患者血清DNA,其中35份样品检测结果与测序法比较.用B、C型质粒DNA倍比稀释及混合样品检测灵敏度来评估该方法.结果:建立了HBV基因分型的快速高通量液相芯片检测方法.182份患者血清检测结果为:B型占24.2％ (44/182),C型占71.4％(130/182),D型为6.6 ％(12/182),BC混合型4.4％(8/182).其中35份样本与测序法比较,除3份混合型测序法未检出外,其它32例结果均相同本方法的灵敏度检测下线为1×103 copies/mL.结论:应用悬液芯片技术进行乙肝病毒的基因分型分析,具有较好的特异性和较高的灵敏度,并有简便、灵活和高通量等优势.该检测系统不仅在科研中有广泛的前景,也有望成为临床推广的多重分子诊断和基因分型的新方法.     

应用TaqMan探针荧光定量PCR技术鉴定Lepr~(db/+)小鼠子代基因型

目的建立一种高效的应用Taq Man探针荧光定量PCR技术对Lepr~(db/+)小鼠子代基因分型的方法。方法提取228例Lepr~(db/+)小鼠子代鼠尾DNA,针对Lepr基因的突变位点(rs1801133)设计1对PCR引物和2条Taq Man探针。设定条件进行实时荧光PCR扩增,用SDS软件对SNP位点进行分型。通过2月龄动物的肥胖表现型验证并进行Hardy-Weinberg平衡检验。结果用建立的Taq Man探针荧光定量PCR方法对228份样本进行检测,其中GG基因型64份,基因型频率为0.1929;GT基因型123份,基因型频率为0.5395;TT基因型41份基因型频率为0.2807。Taq Man探针荧光定量PCR方法分型结果与通过肥胖表现型分型结果比较,灵敏度为97.56%,特异度为99.47%。结论应用Taq Man探针荧光定量PCR技术可实现对Lepr~(db/+)小鼠子代基因位点的早期分型检测,方法简便,高效。     

慢性乙型肝炎患者血清HBV基因分型

为了解长春市慢性乙型肝炎患者血清中的乙型肝炎病毒(HBV)基因型情况及其与临床特点的相关性,应用型特异性引物进行巢式PCR方法对长春市69例慢性乙型肝炎患者血清HBV进行基因分型检测。在69例血清标本中,B型10例(占14.5%);C型41例(占59.4%);B C混合型8例(占11.6%);未分型的患者共10例(占14.5%)。C基因型患者的HBV-DNA定量、HBeAg阳性率明显高于B基因型患者(HBV-DNA:P<0.01;HBeAg:χ2=3.98,P<0.05),C基因型患者肝功检查指标谷丙转氨酶(ALT)和总胆红素(TB IL)均较B基因型患者高(P<0.01)。长春地区存在HBV B基因型、C基因型、B C混合基因型及未分型,C基因型为优势基因,引起的肝脏活动性炎症较B基因型明显。     

双链探针实时荧光PCR核酸检测新技术研究*

目的:采用一种“双链探针”实时荧光PCR技术,提高HBV核酸检测灵敏度,并在同一反应管中实现代谢酶CYP2C19^*2基因型检测。方法:采用双链探针与TaqMan探针同时检测不同浓度HBV血清样本,使用上海宏石SLAN 96实时荧光PCR仪进行核酸Ct值检测和结果统计分析;采用双链探针检测代谢酶CYP2C19^*2不同基因型样本,使用上海宏石SLAN 96实时荧光PCR仪进行核酸Ct值检测和基因型确定。结果:不同浓度HBV血清样本检测,双链探针荧光本底低,检测灵敏度更高,与TaqMan探针检测结果相比,两者核酸检测Ct值存在显著性差异(P<0.05);双链探针检测36份样本的代谢酶CYP2C19^*2基因型,检测结果与Sanger测序结果完全一致。结论:双链探针实时荧光PCR检测技术可完成目的基因的高灵敏核酸检测,也可实现基因型分析。     

太原地区乙肝患者HBV基因分型与细胞免疫功能研究

了解太原地区乙肝病毒基因型分布情况,研究不同基因型乙肝病毒致病性与细胞免疫功能关系。选择慢性乙肝、乙肝肝硬化及乙肝病毒相关肝癌等乙肝病毒感染患者,采用PCR技术检测患者血清HBV-DNA和HBV基因型,用流式细胞仪直接免疫荧光法(FCM)检测患者外周血T淋巴细胞亚群百分率,分析不同病毒基因型与乙肝病程关系以及不同基因型病毒感染患者细胞免疫功能状态。检测136例乙肝病毒感染患者,其中B基因型感染38例,占总数27.9%;C基因型感染93例,占总数70.6%;B/C混合型感染3例,占总数2.2%;D基因型感染2例,占总数1.5%。B型与C型乙肝病毒感染患者的HBsAg水平无区别,B型患者血清HBeAg(+)%高于C型乙肝病毒感染者,慢性无症状乙肝携带者、慢性乙肝、乙肝肝硬化和乙肝病毒相关的原发性肝细胞癌各组中乙肝病毒基因型的分布无差异,但乙肝肝硬化患者与慢性无症状乙肝携带者、慢性乙肝患者的基因型有差异(P<0.01),C基因型感染者HBV-DNA水平、HBeAg阳性率、CD4+细胞和CD4+/CD8+T淋巴细胞比值低于B基因型感染者。太原地区临床乙肝病毒感染患者以C基因型为主,C基因型感染者比B基因型的肝脏功能损害严重,可能与细胞免疫功能降低HBV-DNA水平和HBeAg阳性率高有关。     

广西桂北地区HBV感染者不同免疫状态HBV基因型分布研究

为了了解广西桂北地区乙型肝炎病毒(Hepatitis B Virus,HBV)感染者基因型分布情况及探讨HBV感染不同免疫状态与基因型的关系。将HBV感染者按免疫耐受、免疫清除(应答)和免疫不全(病毒残留)三种免疫状态分类,各选150例,共450例,运用实时荧光定量PCR法检测HBV感染三种不同免疫状态者的HBV基因型。450例中B型为323例、C型为94例、B+C混合型为23例和非B非C型为10例;HBV感染三种免疫状态均B型占多数,分别为70.0%、78.0%和67.33%,不同免疫状态基因型构成比差异无统计学意义;免疫状态与基因型相关性无统计学意义;B型HBV-DNA载量高于C型,各组中年龄≥30岁者C型显著多于30岁者,差异有统计学意义;各基因型间丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、总胆红素(TBil)阳性率差别无统计学意义;男女基因型分布差异无统计学意义。结果表明,广西桂北地区HBV基因型以B型为主,C型占部分比例,少量B+C混合型,偶有未能分型;HBV感染免疫耐受、免疫清除(应答)和免疫不全(病毒残留)三种免疫状态均B型占多数,慢性HBV感染免疫状态与HBV基因型相关性无统计学意义。     

黑龙江地区400例乙型肝炎病毒基因分型与耐药突变研究

目的:运用基因芯片技术分析黑龙江地区乙型肝炎病毒(HBV)基因型分布特征及基因耐药变异情况。方法:随机选择2012年11月至2015年11月本医院乙型肝炎患者血清样本400例,应用PCR-反向点杂交的基因芯片技术对样本血清中HBV基因型及常见4类抗病毒药物耐药相关的多个位点进行检测,并进行数据分析。结果:400例样本中基因型分布以C型为主占83.25%(333例),B型7.25%(29例)、D型0.25%(1例)及混合基因型2.75%(11例);耐药突变位点检出188例,总耐药率为45.19%,其中突变位点236T(4.61%)提示阿德福韦酯单项耐药,耐药率为5.82%(10例),与拉米夫定耐药相关的为126例,突变位点以rt204I和(rt180M+rt240V)为主,显著高于其他抗病毒类药物,耐药风险较高。结论:黑龙江地区乙型肝炎基因分型以C为主,B型和其它混合型较少,且更容易对拉米夫定产生耐药。     

应用LNA-PCR法检测乙型肝炎病毒阿德福韦酯耐药位点基因突变

目的:建立简便、快速、灵敏的锁核酸(locked nucleic acid,LNA)探针实时荧光聚合酶链反应(PCR)检测方法,检测乙型肝炎病毒(hepatitis B virus,HBV)阿德福韦酯(Adefovir dipivoxil,ADV)耐药相关位点(rtA181V、rtN236T)突变。方法:通过基因测序筛选阳性样本,进而构建ADV rt181和rt236位点野生株和突变株重组质粒,设计包含扩增阿德福韦酯rtA181V和rtN236T耐药位点在内的特异性引物和LNA荧光探针,以构建的重组质粒为标准品建立实时荧光PCR反应体系,并通过与基因测序平行检测血清样本以判断检测方法的可行性与准确性。结果:所建立的LNA-PCR法能够检测102copies/ml的HBV中ADV基因突变,同时具备较高的特异性。通过对89例ADV治疗一年后HBV阳性临床样本进行检测,有8例(8.98%)rtA181V突变、5例(5.61%)rtN236T突变、2例(2.24%)rtA181V和rtN236T混合突变,检测结果与测序结果一致。结论:所建立的LNA-PCR法是一种简便、快速、灵敏的基因突变检测方法,能有效的区分单碱基突变,对慢性乙型肝炎患者德福韦治疗过程中耐药突变的监控和抗病毒药物的调整具有指导意义。     

内蒙古呼和浩特地区丙型肝炎病毒基因型分布

为了解内蒙古呼和浩特地区丙型肝炎病毒(HCV)基因型的分布特征,为本地区丙型肝炎的治疗、预防提供基础数据资料。收集呼和浩特地区2014年1月至2015年1月就诊的门诊和住院丙型肝炎患者血清采样标本149份,均为HCV抗体检测阳性且HCVRNA定量检测阳性。QIAGEN柱式病毒RNA提取法提取HCV RNA,反转录成cDNA,巢式PCR法扩增HCVNS5B区,对扩增片段进行测序,在NCBI BLAST上进行序列比对得到相似度最大的参考序列并确定基因型,用Megalign,Clustal W进行序列分析并建立同源关系树,分析呼和浩特地区HCV感染基因型的分布特征,以及基因型与宿主性别、年龄的关系。在测序成功的94份样本中,共检出6个基因型,1b型占73.40%(69/94),2a型占19.14%(18/94),3a、3b、6a型各占2.12%(2/94),6u型占1.06%(1/94)。性别资料明确的93例样本,男女基因型分布无显著差异(P0.05)。年龄资料明确的90例HCV样本,1+2型的患病年龄高于3+6型的患病年龄有统计学意义(P0.05)。得出内蒙古呼和浩特地区HCV感染的基因型1b为主,其次为2a型,但也有3型、6型等基因型的传入。HCV的基因型4型和5型未检测到。     

四种方法检测乙型肝炎病毒基因型的比较

目的比较四种方法检测乙型肝炎病毒基因型的差异性。方法对36例乙型肝炎患者的血清分别采用测序技术,荧光定量PCR技术,恒温扩增技术,基因芯片技术进行乙肝病毒基因型的检测。结果36份血清以测序技术为金标,观测荧光定量PCR技术特异性100%,敏感性83%,恒温扩增技术特异性100%,敏感性89%,基因芯片技术特异性100%,敏感度92%。结论目前临床采用的四种方法检测乙型肝炎病毒基因型的特异性相同,敏感度以测序为金标准,基因芯片技术最灵敏,其次为恒温扩增技术,最后为荧光定量PCR技术。     

Research on Hepatitis B virus Genotypes and Subgenotypes among Bai Nationality in Dali, Yunnan Province

To investigate the distribution of hepatitis B virus （HBV） genotypes and subgenotypes among the Bai nationality in Dali, a total of 100 serum samples from patients with chronic HBV-infection were collected for the detection of HBV genotypes and subgenotypes by genotype-specific primers and restriction fragment length polymorphism （RLFP）, respectively. Among the 100 samples, the proportions of genotype B, C and mixed genotype （B＋C） were 41%, 25% and 34%, respectively. All the genotype B strains belonged to subgenotype Ba In genotype C, 84% were Subgenotype Cs and 12% were subgenotype Ce. The distribution of genotypes B, C and B＋C showed no significant difference between male and female patients （P=0.182） and among the age groups of patients （P=0.812）. The rates of HBeAg/HBeAg positivity were no significantly different among genotypes B, genotype C and mixed genotype （B＋C） （P=0.077/P=0.663）. In Dali, genotypes B, B＋C and C existed among Bai nationality with chronic HBV-infection, and genotype B was the major genotype. Subgenotypes Ba and Cs were the predominant strains in patients with HBV genotype B/C infection. The most prominent characteristic was the higher prevalent rate of mixed genotype （B＋C） in patients.     

Research on hepatitis B virus genotypes and subgenotypes among Bai nationality in Dali, Yunnan Province

To investigate the distribution of hepatitis B virus (HBV) genotypes and subgenotypes among the Bai nationality in Dali, a total of 100 serum samples from patients with chronic HBV-infection were collected for the detection of HBV genotypes and subgenotypes by genotype-specific primers and restriction fragment length polymorphism (RLFP), respectively. Among the 100 samples, the proportions of genotype B, C and mixed genotype (B C) were 41%, 25% and 34%, respectively. All the genotype B strains belonged to subgenotype Ba. In genotype C, 84% were Subgenotype Cs and 12% were subgenotype Ce. The distribution of genotypes B, C and B C showed no significant difference between male and female patients (P=0.182) and among the age groups of patients (P=0.812). The rates of HBeAg/HBeAg positivity were no significantly different among genotypes B, genotype C and mixed genotype (B C) (P=0.077/P=0.663). In Dali, genotypes B, B C and C existed among Bai nationality with chronic HBV-infection, and genotype B was the major genotype. Subgenotypes Ba and Cs were the predominant strains in patients with HBV genotype B/C infection. The most prominent characteristic was the higher prevalent rate of mixed genotype (B C) in patients.     

部分肝病患者和健康人血清中HBV基因型分析

确定了内蒙古海拉尔地区乙型肝炎病毒 (HBV)感染者HBV基因型的分布情况。采用基因型特异引物的巢式聚合酶链式反应方法对 38例无症状HBV携带者 ,3例急性肝炎 ,41例慢性肝炎 ,3例肝硬化 ,3例肝癌患者和38例健康人血清中HBV基因型进行分析。结果显示 ,12 6例中有 91例检测到HBVDNA ,其中 ,HBVB型 ,C型分别为 11例 ( 12 .1% )和 6 8例 ( 74.7% ) ,同时检测到B型和C型者有 8例 ( 8.8% ) ,有 4例 ( 4.4% )尚未确定基因型别。可见 ,在海拉尔地区HBV感染同时存在HBVB型和C型 ,而且C型是这一地区流行的主要基因型。     

A type-specific nested PCR assay established and applied for investigation of HBV genotype and subgenotype in Chinese patients with chronic HBV infection

ABSTRACT: BACKGROUND: Many studies have suggested that hepatitis B virus (HBV) genotypes show not only geographical distribution and race specificity, but also are associated with disease progression and response to interferon treatment. The objective of this study was to develop a nested polymerase chain reaction (nPCR) assay for genotypes A-D and subgenotypes B1, B2, C1 and C2 of hepatitis B virus (HBV) and to investigate the distribution characteristics of HBV genotypes/subgenotype in China. METHODS: After redesigning the primers and optimizing the reaction conditions using common Taq polymerase, the sensitivity, specificity and reproducibility of the method were evaluated using plasmids and serum samples. In total, 642 serum samples from patients with chronic HBV infection were applied to investigate the distribution of HBV genotype and subgenotype in China. RESULTS: The genotype and subgenotype could be identified when the HBV DNA load of a sample was ≥10(2.3) IU/mL. For the 639 successfully genotyped samples, the sequencing results of 130 randomly selected samples (20.3%, 130/639) were consistent with those of the nPCR method. The present study showed that HBV genotype B (11.2%, 72/642), C (68.2%, 438/642) and D (7.2%, 46/642) were circulating in China, while genotype C was the dominant strain except for western region where genotype D was the prevalent strain. The main subgenotypes of genotypes B and C were B2 (87.5%, 63/72) and C2 (92.9%, 407/438), respectively. CONCLUSIONS: The low-cost nPCR method would be a useful tool for clinical and epidemiological investigation in the regions where genotypes A-D are predominant.     

An improved reverse dot hybridization for simple and rapid detection of adefovir dipivoxil-resistant hepatitis B virus

Early detection of adefovir dipivoxil-resistant mutants during long-term treatment of chronic hepatitis B virus (HBV) infection with this drug is of great clinical importance. We developed an improved reverse dot hybridization test for simple and rapid detection of the rtA181V/T and rtN236T mutations associated with adefovir dipivoxil resistance in chronic hepatitis B patients. Probes were designed for genotypes B, C, and D of this resistance characteristic; a total of 70 clinical samples were analyzed with this improved reverse dot hybridization assay. Its usefulness was validated by comparing with sequencing data. Discordant results were confirmed by subclone sequencing. This reverse dot hybridization assay was sufficiently sensitive to detect 10(3) copies/mL; it also detected adefovir dipivoxil-resistant mutant strains when they comprised more than 5% of a mixed virus population. This reverse dot hybridization array correctly identified adefovir dipivoxil-resistant mutants; it had high concordance (98.5%) with direct sequencing data. There was no clear relationship between the HBV genotype and the development of adefovir dipivoxil-resistant mutants. This reverse dot hybridization assay proved to be simple and rapid for detection of rtA181V/T and rtN236T mutations associated with resistance to adefovir dipivoxil.     

Response to treatment in Brazilian patients with chronic hepatitis C is associated with a single-nucleotide polymorphism near the interleukin-28B gene

A single-nucleotide polymorphism (SNP) upstream of interleukin (IL)28B was recently identified as an important predictor of the outcome of chronic hepatitis C patients treated with pegylated interferon plus ribavirin (PEG-IFN/RBV). The aim of this study was to investigate the association between the IL28B gene polymorphism (rs12979860) and virological response in chronic hepatitis C patients. Brazilian patients (n = 263) who were infected with hepatitis C virus (HCV) genotype 1 and were receiving PEG-IFN/RBV were genotyped. Early virological response (EVR) (12 weeks), end-of-treatment response (EOTR) (48 weeks), sustained virological response (SVR) (72 weeks) and relapse were evaluated using conventional and quantitative polymerase chain reaction (PCR) assays. The frequency of the C allele in the population was 39%. Overall, 43% of patients experienced SVR. The IL28B CC genotype was significantly associated with higher treatment response rates and a lower relapse rate compared to the other genotypes [84% vs. 58% EVR, 92% vs. 63% EOTR, 76% vs. 38% SVR and 17% vs. 40% relapse rate in CC vs. other genotypes (CT and TT), respectively]. Thus, the IL28B genotype appears to be a strong predictor of SVR following PEG-IFN/RBV therapy in treatment-naïve Brazilian patients infected with HCV genotype 1. This study, together with similar research examining other SNPs, should help to define adequate protocols for the treatment of patients infected with HCV genotype 1, especially those with a poor prognosis.     

Prevalence of HBV genotypes among Egyptian hepatitis patients

Phylogenetic analysis has led to the classification of hepatitis B virus into eight genotypes, designated A to H. The genotypes have differences in biological properties and show heterogeneity in their global distribution. These attributes of the genotypes may account not only for differences in the prevalence of hepatitis B virus mutants in various geographic regions, but also makes them responsible for differences in the clinical outcome and response to antiviral treatment in different population groups. Africa is one of the highly endemic regions of HBV with five genotypes (A–E) identified. Almost all patients in the Mediterranean area are infected with genotype D. However, there is little information of genotype distribution in Egypt. A total of 140 Egyptian patients with hepatitis B surface antigen (HBsAg) positive were enrolled in this study. Of the 140 patients, only 100 patients were HBV DNA positive and only these were included in the study. They were classified into 20 patients with acute hepatitis (AH), 75 patients with chronic active hepatitis (CAH) and 5 patients with hepatocellular carcinoma (HCC). HBV genotypes were determined using INNO-LiPA methodology which is based on the reversed hybridization principle. This study showed that genotype D constituted 87% of the total infections (75 CAH cases, 7 AH cases and 5 HCC cases). The other 13% showed mixed infections of D/F. These findings show that the most prevalent genotype in Egypt is genotype D especially in CAH and HCC patients while the mixed type D/F is only encountered in AH.