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目的 了解重型乙型肝炎( 乙肝) 病人血清乙肝病毒(HBV)DNAC基因启动子(CP) 的变异。方法 对用聚合酶链反应(PCR) 法扩增的血清HBVDNA 直接测序。结果 7 例亚急性重型肝炎病人的HBV 分离株CP区分别有2~12 个替代变异,1 例病人有11bp 的碱基插入。CP变异主要发生于CP的第1 和第2 个AT丰富区,nt1 762 和nt1 764 的替代变异见于7 例亚急性重型肝炎病人的4 例中,是CP变异的热点,其中3 例HBeAg 阴性,说明和HBeAg 阴性表型相关。CP的第3 个AT丰富区、HBV逆转录起始位点(DR1) 和前C基因、前基因组转录起始位点未见变异。结论 重型肝炎病人的HBVCP区存在较多的变异,CP变异主要发生于和前C基因相关的第1 和第2 个AT丰富区,可能和HBeAg 阴性表型相关  相似文献   

3.
目的 探讨乙型肝炎病毒 (HBV)基本核心启动子 (BCP)及前C区突变与基因型之间的关系。方法 随机选取 113例慢性HBV感染者外周血 ,采用INNO LiPA法测定BCPT176 2 A176 4双突变及前C区A1896突变 ,测定HBVS基因序列明确基因型。结果 在C基因型感染者中BCPT176 2 A176 4双突变率明显高于B基因型感染者 ,差异有显著性 (34.2 %∶10 % ,χ2 =6 .74 ,P <0 .0 1) ,而前C区A1896突变率在B基因型和C基因型感染者中差异无显著性 (2 .5 %∶4 .1% ,χ2 =0 .0 0 ,P >0 .0 5 )。结论 与B基因型相比 ,C基因型感染者更易发生BCPT176 2 A176 4双突变。  相似文献   

4.
The evolution of precore stop codon mutation (A1896) and dinucleotide mutation (T1762/A1764) in the basic core promoter (BCP) of hepatitis B virus (HBV) genome during transient seroconversion and seroreversion of hepatitis B e antigen (HBeAg) remains unclarified. Five HBeAg-positive HBV carriers who experienced transient seroconversion followed by seroreversion of HBeAg (Group I, 3.3%) and 3 HBeAg-negative HBV carriers with documented reversion of HBeAg (Group II, 2.5%) in a prospective cohort of 272 patients with chronic hepatitis B were thus identified. The sequential changes at the precore nucleotide 1896 and BCP dinucleotide 1762/1764 were determined by polymerase chain reaction and direct sequencing. At enrollement, precore A1896 and BCP T1762/A1764 were noted in 4 (50%) and 1 (13%) of the eight patients. During a median follow-up period of 58 months (range: 31-76 months), 12 episodes of transient HBeAg seroconversion followed by seroreversion were encountered in Group I patients and 3 episodes of HBeAg seroreversion in Group II patients. Accompanying acute exacerbations were found in two-thirds of patients with either HBeAg seroconversion or seroreversion. Overall, precore nucleotide A1896 remained identical in 73% and 83% of the seroconversion and seroreversion events, respectively. BCP dinucleotide T1762/A1764 remained unchanged in 94% and 92% of the seroconversion and seroreversion events, respectively. At the end of follow-up, only one had both precore and BCP mutations. In conclusion, these data suggested that HBeAg seroreversion might be due to the lack of sustained precore and BCP mutations after HBeAg seroconversion. Although uncommon, HBeAg seroreversion can be associated with hepatitis exacerbation.  相似文献   

5.
慢性HBV C基因启动子变异的检测   总被引:3,自引:0,他引:3  
目的 了解慢性乙型肝炎病毒(HBV)C基因启动子变异的情况以及对病毒血清学的影响。方法 应用错配聚合酶链反应特异性扩增含有HBV C基因启动子的片段,扩增产物用限制性内切酶Bcl I酶切,琼脂糖凝胶电泳后,观察酶切后的限制性片段长度多态性(RFLP)图谱,分析C基因启动子区段的核苷酸(nt)1762由碱基A→T和(nt)1764碱基由G→A的变异,并经直接测序分析证实RFLP结果。结果 110例慢  相似文献   

6.
Background/AimsHepatitis B core antibody (anti-HBc)-positive donors are used as an extended donor pool, and current guidelines recommend the usage of nucleos(t)ide analogues (NAs) as prophylaxis for preventing de novo hepatitis B virus infection (DNH). We analyzed the long-term outcomes of a large cohort of liver transplantation (LT) patients receiving anti-HBc-positive grafts and evaluated the risk of DNH when hepatitis B immunoglobulin (HBIG) monotherapy was used as prophylaxis. We also compared the cost-effectiveness of HBIG and NAs.MethodsWe retrospectively reviewed 457 patients with anti-HBc-positive grafts and 898 patients with anti-HBc-negative grafts who underwent LT between January 2001 and December 2018. We compared recipient characteristics according to the anti-HBc status of the donor, and compared the costs of using NAs for the rest of the patient’s life and using HBIG to maintain hepatitis B surface antibody titers above 200 IU/L.ResultsThe 1-, 5-, and 10-year patient survival rates were 87.7%, 73.5%, and 67.7%, respectively, in patients with anti-HBc-positive grafts, and 88.5%, 77.4%, and 70.3%, respectively, in patients with anti-HBc-negative grafts (P=0.113). Among 457 recipients with anti-HBc-positive grafts, 117 (25.6%) were non-HBV recipients. The overall incidence of DNH was 0.9%. When using HBIG under insurance coverage, the cumulative cost was lower compared with using NA continuously without insurance coverage in Korea.ConclusionsAnti-HBc-positive grafts alone do not affect patient survival or graft survival. HBIG monoprophylaxis has good outcomes for preventing DNH, and the patient’s long-term cost burden is low in Korea because of the national insurance system in this cohort.  相似文献   

7.
The association of precore stop codon mutation (A1896), dinucleotide mutation (T1762/A1764) in the basic core promoter of hepatitis B virus (HBV) genome, and genotype of HBV with fulminant or subfulminant hepatitis remains controversial. We studied HBV genotypes as well as mutations in the precore and basic core promoter regions in 18 hepatitis B carriers with fulminant or subfulminant hepatitis. Genotyping of HBV was performed by polymerase chain reaction-restriction fragment length polymorphism. The presence of A1896 in the precore gene and T1762/A1764 in the basic core promoter gene was determined by the polymerase chain reaction and by direct sequencing. Eighteen age- and sex-matched patients with chronic active hepatitis B served as controls. The HBV was of genotype B in 14, genotype C in 3, and unclassified in 1. Precore A1896 mutation occurred in 12 (67%) of the 18 patients. In contrast, the prevalence of basic core promoter mutation was only 17%. Nevertheless, the distribution of HBV genotype and the prevalence of precore A1896 mutation in the fulminant and subfulminant hepatitis patients were similar to those in 18 control patients. In conclusion, the genomic variability of HBV does not seem to contribute to the fulminant and subfulminant exacerbation of chronic hepatitis B in Taiwanese HBV carriers.  相似文献   

8.
目的:设计特异性结合乙肝病毒核心启动子(HBVCp)的锌指蛋白(ZFP),观察ZFP在体外对HBV转录的抑制情况。方法:利用Zinc finger tools设计特异性结合HBV Cp的ZFP。将ZFP核苷酸序列人工合成后克隆至pEGFP-N1和pcDNA3.1(+),构建真核表达质粒pEGFP-N1/ZFP-Flag和pcDNA3.1(+)/ZFP。通过倒置荧光显微镜、RT-PCR和Western blot鉴定pEGFP-N1/ZFP-Flag在COS-7中的表达情况;将pcDNA3.1(+)/ZFP转入HepG2.2.15细胞后24 h,采用ELISA和FQ-PCR检测上清液中HBeAg和HBV DNA含量,RT-PCR检测细胞内HBV mRNA水平。结果:ZFP在COS-7细胞中能正常表达。与空质粒组相比,ZFP组细胞培养上清液中HBV DNA拷贝量和HBeAg含量明显降低(P<0.05),细胞内HBV mRNA也显著减少。结论:人工设计的ZFP可以在真核细胞内正常表达,并能有效抑制HBV的转录。  相似文献   

9.
目的探讨HBV前C区(PreC)及基本核心启动子(BCP)突变与慢性乙型肝炎病毒(HBV)感染者疾病进展的关系。方法收集88例慢性HBV感染者血清标本,包括36例无症状携带者(其中24例为HBV携带者,12例为HBsAg携带者)、36例慢性乙型肝炎(慢性乙肝)和16例肝硬化患者。所有标本均经型特异性引物PCR法鉴定为HBVC基因型,并用巢氏PCR法扩增HBVPreC和BCP基因片段,用PCR产物直接测序法测序,然后用ClustalW1.8软件进行序列分析。结果在50例HBeAg阳性患者中,无症状携带者、慢性乙肝和肝硬化组的T1762/A1764双突变率和T1846突变率分别为12.5%、42.1%、100%和0%、5.3%、28.6%,差异均有统计学意义(P值分别为0.03和0.02)。在38例HBeAg阴性HBV感染者中,无症状携带者、慢性乙肝和肝硬化组的T1762/A1764双突变率分别为16.7%、58.8%和66.7%,差异无统计学意义(P=0.08)。肝硬化组的C/G1753突变率显著高于无症状携带者及慢性乙肝组(分别为55.6%、8.3%、11.8%,P=0.01),其A1896突变率也高于无症状携带者组(分别为55.6%、8.3%,P=0.01)。结论HBVT1762/A1764双突变与C基因型HBV慢性感染者的疾病进展有关。  相似文献   

10.
乙型肝炎病毒C基因启动子及前C变异的动态研究   总被引:11,自引:0,他引:11  
目的明确乙型肝炎病毒(HBV)C基因启动子(BCP)与前C变异株在慢性乙型肝炎患者中的动态消长,及与HBeAg血清学状态的关系。方法对32例慢性乙型肝炎患者的105份系列血清进行错配聚合酶链反应(PCR)-限制性片段长度多态性分析,并对其中15例患者系列血清标本的PCR产物进行直接测序。结果BCP和A83变异株感染率均明显增高(62.5%>46.9%;31.3%>12.5%);BPC变异株更多地(14/16)表现为优势积累,且先于HBeAg血清阴转;BCP野株/变异株比例变化影响HBeAg血清学的稳定性。结论两种类型的变异株在炎症活动中均具有选择优势,最终造成HBeAg(-)的HBV感染;可能与HBV感染之持续有关。  相似文献   

11.
Genetic variability of hepatitis B virus (HBV) in the C gene and its association with the different stages of chronic liver disease has been studied inadequately with controversial results. The objectives of the current study were to determine the frequency of core promoter and precore mutations in chronic hepatitis B in Tunisia and to evaluate their impact on viral replication and disease progression. Sequencing was performed in upstream regulatory sequence (URS), pre‐core (PreC) and basal core promoter (BCP) regions for 123 chronic infected patients by HBV genotype D at different status of disease. Mutations were detected in 98.4% of cases, affecting URS, BCP and Pre‐C in 95.1%, 95.9% and 87.8% respectively. Multi‐mutations increased significantly from asymptomatic carrier to advanced liver disease status. G1896A (74.8%), G1764A/T/C (71.5%), G1899A (54.4%) and T1678C (52%) were the most common. Special attention should be paid to A1703T, T1678C/G‐A1703T, and A1652G‐A1679G mutations probably specific of Tunisians sequences; they were observed in 40.6%, 41.5% and 30.1% respectively. A1679G/C, T1753C/G/A, A1762T/G and A1762T‐G1764A were more prevalent in older patients. High DNA levels were associated with G1899A or G1764T/C‐C1766G‐C1799G and advanced liver disease with mutations at positions 1762, 1764 and/or 1899 alone or in double or triple mutations. It was also shown that substitutions at nucleotides 1762, 1764 and 1899 have an impact on the disease progression. It is the first report for specific mutations in the URS region for genotype D. It should be completed by studying eventual correlation with clinical progression and the response to treatment. J. Med. Virol. 84:1719–1726, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

12.
丙肝病毒(HCV)及乙肝病毒(HBV)双表达载体的构建及表达   总被引:3,自引:0,他引:3  
目的 :为探索HCV/HBV高效联合基因免疫策略 ,构建具有 2套独立表达单元的HCV/HBV真核表达载体。方法 :分别将与HCV核心区基因互补的cDNA和HBV核心区基因克隆于具有 2套独立表达单元的真核表达载体pRSC的巨细胞病毒启动子和RSV启动子下游 ,称为pRSC HBV/HCV ,转染SP2 / 0细胞 ,通过免疫荧光和Western印迹法观测蛋白的表达 ,免疫Balb/c小鼠 ,用酶联免疫小鼠体液免疫应答。结果 :pRSC HBV/HCV转染SP2 / 0细胞可见HBcAg及HCV核蛋白染色阳性荧光细胞 ,SDS Page电泳显示在 14kD及 2 1kD处均可见蛋白条带 ,与HBcAg及HCV核蛋白的的理论预期值一致 ,Western印迹分析显示在 14kD及 2 1kD处可见特异性的蛋白条带。 5只免疫鼠中全部出现抗 HCV及抗 HBV抗体 ,而对照组全阴性。结论 :pRSC HBV/HCV可分别表达HBcAg及HCV核蛋白 ,免疫Balb/c小鼠后可诱导其体液免疫应答 ,为进一步开展HCV/HBV联合基因免疫奠定了实验基础。  相似文献   

13.
Calcium ions affect the hepatitis B virus core assembly   总被引:2,自引:0,他引:2  
Choi Y  Gyoo Park S  Yoo JH  Jung G 《Virology》2005,332(1):454-463
Previous report showed that cytosolic Ca2+ induced by hepatitis B virus X protein (HBx) promotes HBV replication. In this study, in vitro experiments showed that (i) HBV core assembly in vitro was promoted by Ca2+ through the sucrose density gradient and the analytical ultracentrifuge analysis. Also, (ii) transmission electron microscope analysis demonstrated these assembled HBV core particles were the capsids. Ex vivo experiments showed that the treatment of BAPTA-AM and cyclosporine A (CsA) reduced HBV capsids in the transfected HepG2 cells. In addition to that, the treatment of Thapsigargin (TG) increased HBV capsids in the transfected HepG2 cells. Furthermore, we investigated the increased HBV core assembly by HBx. The results show that the increased cytosolic calcium ions by HBx promote the HBV core assembly.  相似文献   

14.
目的观察磷酸脂酶抑制剂环孢素A(CSA)对HBcAg表达和定位的影响,了解HBV生活的周期。方法以30μg/ml的CSA处理HepG2.2.15细胞2d或4d;共聚集显微镜观察细胞内HBcAg和HBsAg亚细胞定位;TUNEL方法检测细胞凋亡。结果对照组HepG2.2.15细胞中HBcAg主要定位于胞质。CSA处理2d后可使胞质中HBcAg和HBsAg水平下降,细胞核内HBcAg水平升高,可见约5%细胞发生凋亡。CSA处理4d后细胞核内HBcAg水平进一步提高,约25%细胞核内表达强度明显高于胞质,并约有30%细胞发生凋亡。结论CSA可促使HepG2.2.15细胞内HBcAg进入细胞核。HBcAg的核内表达定位增强可能与蛋白磷酸化水平增高,及细胞衰老或者凋亡有关。  相似文献   

15.
乙型肝炎病毒C基因启动子区准种与变异特点的研究   总被引:17,自引:0,他引:17  
目的 研究乙型肝炎病毒(HBV)C基因启动子区难种与变异的特点。方法 以中国株HBV基因序列为依据,设计特异性聚合酶链反应(PCR)引物,自3例慢性HBV感染患者外周血血清中扩增HBVCP序列,克隆入pGEM Teasy质粒,随机挑选克隆进行DNA测序以确定病毒的变异程度。结果 测序结果发现HBV CP序列高度保守,但在TATA样盒(1—3)可发生多种突变,其中184nt(T→C)位替换突变员为常见;在直接重复序列(DR)I上游存有一缺失突变高发区33.3%(5/15)。结论 CP区内有一缺失高变区,TATA样盒3的变异可能影响前C蛋白的表达。结果 提示HBV长期携带者体内有HBV准种共存。  相似文献   

16.
In chronic hepatitis B virus (HBV) infection, mutations develop frequently at nucleotides 1,762/1,764 in the X protein open reading frame, where the core promoter is also located. By using a modified allele-specific polymerase chain reaction method, the longitudinal emergence of the A→T mutation at nucleotide 1,762 was studied in relation to precore mutations, genotype, and liver damage. First, samples from 38 carriers that were drawn before and after hepatitis B e (HBe) seroconversion were tested. T-1,762 mutant strains increased during HBe seroconversion (P = 0.004). In the HBe antigen-negative (HBeAg) phase, T-1,762 mutants were found in 71% (12 of 17) of patients without compared with 33% (6 of 18) of patients with a concomitant precore mutation that prevents HBeAg synthesis (P = 0.08). Second, in 55 HBeAg+ patients, the T-1,762 mutant was found to be associated with more liver inflammation (P = 0.04) and fibrosis (P = 0.02), as measured by histology activity index (HAI) scores. The results show that the nucleotide (nt) 1,762 A→T mutation often develops during HBe seroconversion, particularly in strains without precore mutations that prevent HBeAg production. For unknown reasons, the T-1,762 mutant was rare in genotype B strains. The presence of a T-1,762 mutant in the HBeAg+ phase may be useful for identifying immunoactivation in previously immunotolerant carriers, which could be valuable for selecting patients for interferon therapy. J. Med. Virol. 55:185–190, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

17.
重组乙肝病毒核心基因DNA与表面抗原-抗体共免疫应答研究   总被引:13,自引:0,他引:13  
目的:了解小鼠对乙肝病毒核心抗原(HBcAg)基因免疫及与乙肝表面抗原-抗体复合物(HBsAg-抗HBs)联合免疫的应答。方法:用表达乙肝病毒核心抗原N端144个氨基酸的重组质粒DNA(简称pHBc144)100μg及含1μgHBsAg的重组乙肝表面抗原-鼠抗体组建的复合物(简称sIC)免疫Balb/c小鼠。用ELISA法检测血清抗体IgG和IgG1、IgG2a亚类的效价。用半定量PCR法分别检测鼠脾细胞IFN-γ及IL-4的mRNA。结果:pHBc144及sIC联合免疫鼠的抗HBs IgG、IgG1、IgG2a效价均显著高于sIC组(P<0.05)。同时小鼠还可产生抗HBc及由HBsAg、HBcAg特异诱生的IFN-γ及IL-4。但与sIC共免疫,小鼠对HBcAg诱生的IFN-γ mRNA有所降低。结论:可用HBcAg基因与sIC共免疫,以获得针对乙肝病毒2种结构蛋白的免疫应答。  相似文献   

18.
Adefovir dipivoxil (ADV) has demonstrated clinical activity against both wild-type and lamivudine-resistant hepatitis B virus (HBV). We analyzed the evolution of viral load and the changes of polymerase and precore/core promoter sequences in lamivudine-resistant virus during ADV therapy. The authors studied 14 patients who had breakthrough hepatitis after lamivudine therapy. Serial sera were obtained prior to adefovir administration and at 3, 6 and 12 months after ADV therapy. Nucleotide sequences of polymerase and the precore/core promoter from the hepatitis B virus were analyzed. The median serum HBV DNA decrease with adefovir treatment was 4.35 log(10) copies/mL at 12 months. Tyrosine-methionine-aspartate-aspartate (YMDD) mutants were found in 12 patients among the 14 patients with lamivudine resistance. The YMDD mutant viruses reversed to the wild-type in 6 patients out of the 12 patients after 3-6 months of ADV after discontinuing lamivudine therapy. In the analysis of the nucleotide sequences of the precore/core promoter gene, core promoter mutants in 12 patients were replaced by wild-type virus in three patients (25%), while precore mutants in four patients were replaced by the wild-type in three patients (75%). The results demonstrate the patterns of polymerase and precore/core promoter mutations in lamivudine-resistant hepatitis B viruses and the reversion from the mutant to the wild-type in some patients. In addition, despite several mutations in the polymerase during ADV therapy, ADV effectively suppressed HBV replication without the emergence of resistant viral mutants.  相似文献   

19.
The nucleotide sequences of the core upstream and precore regions (371 nucleotide length, nt. 1604-1974) of hepatitis B virus (HBV) were analysed sequentially in three subjects who were positive serorogically for anti-HBe and had acute clinical exacerbation after immunosuppressive treatment. These patients were asymptomatic HBV carriers before therapy. The results revealed that the mutant with an 8-bp deletion (nt. 1768–1775) located in the basic core promoter region was dominant in the asymptomatic HBV carrier phase in two of three subjects. After exacerbation, however, such mutant clones possessing 8-bp deletion disappeared or decreased in number and were replaced by the clones possessing a precore stop codon mutation G to A (nt. 1896) or by the clones possessing additional contiguous point mutations A to T (nt. 1762) and G to A (nt. 1764) and a new point mutation C to T (nt. 1653). Possible relationships between acute exacerbation of liver function accompanied by mutation and the transition of the dominant clones were discussed. J. Med. Virol. 53:266–272, 1997. © 1997 Wiley-Liss, Inc.  相似文献   

20.
Few studies have reported on the clinical characteristics of hepatocellular carcinoma (HCC) at the time of diagnosis with regard to pre-S and basal core promoter (BCP) mutations. In this study, the clinical features and prognosis of 126 Korean HCC patients were examined with respect to pre-S deletion and BCP mutations of hepatitis B virus. The proportion of HCC patients according to tumor-node-metastasis stage are as follows: 8.7% in stage I, 31% in stage II, 30.2% in stage III, 21.4% in stage IV-A, and 8.7% in stage IV-B. Overall, 40.5% of HCC patients were treated by surgery or ablation, 59.5% by other methods. Patients were divided according to pre-S deletion and BCP mutations (103 without pre-S deletion, 23 with pre-S deletion; 44 without BCP mutation, 82 with BCP mutation). The tumor characteristics and prognosis were evaluated between the groups, including size, number, type, vessel invasion, portal vein thrombosis, and metastasis. No significant difference in tumor characteristics between the HCC patients with pre-S deletion was observed, compared with the HCC patients without pre-S deletion. In contrast, the survival rate was lower in those with pre-S deletion than in those without it (P = 0.024). No difference in tumor characteristics was found in non-BCP and BCP mutation patients. Unlike the pre-S deletion group, no difference was observed in survival rate between the non-BCP and BCP patients. In conclusion, pre-S deletion and BCP mutations did not affect the initial tumor features. However, pre-S deletion was an independent risk factor affecting HCC survival.  相似文献   

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