HBV转录后调节序列中与干扰素α应答有关位点的初步鉴定与分析

目的筛选乙型肝炎病毒(HBV)感染者转录后调节序列中与干扰素α治疗应答有关的差异位点。方法采用PCR反应产物直接测序法,对31例HBV感染者血清中HBV DNA上的转录后调节序列(HPRE)片段扩增后测序,与GenBank中来源于欧美人群的乙型肝炎序列进行比较,并结合临床资料进行分析。结果在中国慢性HBV感染者HPRE的β2区,存在3个位点变化,分别为nt1 504 (T→C),占75.0%;nt1 508 (C→T),占57.1%,C→G,占10.7%;nt1509 (C→T),占60.7%。而在欧美HBV感染者的HBV DNA序列中均不存在上述位点变化。HPRE位点差异的发生率与HBV DNA水平未见明显相关。结论不同种族HBV感染者转录后调节序列的差异可能与干扰素α治疗的应答性有关。     

高效抗逆转录病毒治疗的HIV/HBV重叠感染者耐药HBV毒株C区和P区基因序列分析

目的：进一步研究乙肝病毒(HBV)耐高效抗逆转录疗法(HAART)的耐药机制。方法：用HBV—DNA荧光定量试剂盒，定量检测36例HAART治疗的HIV／HBV重叠感染者中HBV—DNA，用HBV—DNAC区和P区引物常规扩增HBV—DNAC区和P区产物，PCR产物纯化后测序，用BLAST软件分析序列，与国际HBV基因库对比。结果：36例HAART治疗的HIV／HBV重叠感染者中，HBV—DNA阳性4例(11．1％)，血清中HBV—DNA拷贝数3例在10^4copies／ml级，1例在10^7copies／ml级。对1例HBV—DNA在10^7copies／ml级标本进行HBVDNAC区和P区序列测定，用BLAST软件与国际基因库对比，结果，C区nt2412位T→C，nt2413位T→C，P区nt741位A→G(YMDD→YVDD)。结论：HAART治疗的HIV／HBV重叠感染者，HBV耐药可能与HBV—DNAC区和P区联合变异有关。     

HBV转录后调节序列中与干扰素α应答有关位点的鉴定及生物学意义初探

乙型肝炎病毒(Hepatitis B virus,HBV)的遗传多样性是否影响不同种族的HBV感染者对干扰素α的应答,目前尚不十分清楚。据CMJ报道。第一军医大学附属南方医院感染内科邢同京等人的研究表明:HBV感染者转录后调节序列中存在与干扰素α治疗应答有     

乙型肝炎病毒C基因启动子变异、HBV DNA及细胞因子与原发性肝癌的关系

目的：探讨乙型肝炎病毒C基因启动子（HBVBCP）变异、HBVDNA及细胞因子与原发性肝癌（HCC）的关系。方法：将176例HBV慢性感染者分为慢性肝病组（156例）和HCC组（20例）。采用PCR微板核酸杂交结合ELISA检测显示技术检测HBVBCP区核苷酸（nt）1762碱基A→T和1764碱基G→A联合突变。并检测两组患者的血清HBVDNA含量及细胞因子白细胞介素-10（IL-10）、IL-12、肿瘤坏死因子α（TNF—α）、γ干扰素（IFN-γ）水平。结果：HBVBCP变异在HCC组的阳性率（70．0％）显著高于慢性肝病组（37．8％，P〈0．01）。HCC组的血清HBVDNA含量、TNF—α水平均显著高于慢性肝病组（P〈0．05，P〈0．01），而血清IL-10、IL-12和IFN-γ水平与慢性肝病组无显著性差异（均P〉0．05）。结论：HBV BCP变异与原发性肝癌关系密切．且血清TNF—α及HBV DNA复制水平在原发性肝癌的发生中可能也起到主要的作用．     

HBV DNA PreC／C和BCP片段基因多态性研究

目的：研究乙肝患者HBV DNA核苷酸（nt）1735～1965片段突变及其临床意义。方法：PCR扩增HBV DNA nt1735～1965片段，将产物进行HBV DNA测序。结果：在68例乙肝患者中。nt1735～1965突变阳性率为48．5％，检出点突变总数168个，频率前10位的是nt1764（58．8％）、1762（44．1％）、1799（20．6％）、1766（14．7％）、1896（13．2％）、1754（8．8％）、1899（8．8％）、1768（7．4％）、1814（7．4％）及1913（7．4％）。同时，首次检出nt1907、1922、1923位点突变。     

隐匿性HBV感染者血清中HBVS基因变异分析

目的分析隐匿性HBV感染者的HBV DNA基因序列,查找基因变异位点,探讨隐匿性HBV感染的分子生物学机制。方法选择不明原因肝病患者76例,分离患者血清,采用巢式PCR检测患者血清HBV DNA,阳性者随机抽取8例扩增nt56-nt767 HBV S区DNA片段并采用直接测序法检测S区基因的变异情况。结果本组76例不明原因肝病患者中16例血清HBV DNA阳性,随机选择8例测序比对发现,a决定簇内nt587出现G→A的突变,推导氨基酸由甘氨酸变异为精氨酸,即较为常见的G145R突变。a决定簇外nt355、nt484碱基均由A→C,推导氨基酸无变化,nt512碱基由C→A,推导氨基酸由脯氨酸变异为苏氨酸。结论 HBV S区的变异影响了体内HBV清除,导致病毒的低水平复制,其中G145R突变是隐匿性HBV感染发生的原因之一。     

我国特有三个小型猪品系PPARα基因的多态性分析

目的分析我国特有三个小型猪品系巴马小型猪、五指山小型猪,中国农大小型猪过氧化物酶体增殖物激活受体α（PPARα）基因exon5-intron5这段序列的单核苷酸多态性（SNPs）分布特点,为我国小型猪在糖尿病和代谢性疾病的研究中提供基础资料。方法提取三个品系小型猪血液基因组DNA,以基因组DNA为模板,应用多聚合酶链式反应（PCR）技术在合成的特异性引物引导下扩增,将PCR产物纯化,然后进行测序,再将测序结果在NCBI中进行BLAST比对分析。结果测序结果显示：在PPARα基因exon 5-intron 5中存在12个单核苷酸位点,分别为83G→A,133C→T,134G→T,141C→G,146T→G,150T→G,179C→A,196C→T,205C→T,212C→T,218T→C,219T→C,其中只有83G→A这一单核苷酸突变位点位于编码区内,密码子TCA→TCG,氨基酸为Ser163Ser。结论在三个品系小型猪中PPARα基因多态位点的分布存在差异,表明小型猪的品种不同多态情况不同。     

乙型肝炎病毒C基因启动子变异与基因型和肝硬化的关系

目的 研究HBV C基因启动子(CP)和前C基因变异与HBV基因型和病情的关系。方法 通过DNA扩增、基因序列分析检测44例慢性乙型肝炎(CH)，29例肝硬化(LC)患者的血清HBV S基因序列以确定其基因型，测定HBVCP和前C区序列以确定其变异状况。结果 (1)CP双变异(nt 1762A→T和1764G→A)的发生率肝硬化组为75．9％，慢性乙型肝炎组为45.5%，两组间差别有显著性意义(P＜0.05)。(2)LC患者的C基因型检出率为69．0%，CH患者的C基因型检出率为43.2％，二者间差别有显著性意义(P＜0.05)。(3)C基因型HBV感染者CP双变异发生率为69.2％，B基因型HBV感染者CP双变异发生率为44．1％，二者间差别有显著性意义(P＜0.05)。结论 CP双变异与C基因型密切相关，并且导致病情向肝硬化发展。     

IFN-γ基因多态性与HBV感染不同结局之间的关系

目的：探讨IFN-γ基因多态性与HBV感染不同临床转归之间的相关性。方法：应用聚合酶链反应-序列特异性引物法（PCR-SSP）检测60例自限性HBV感染者（SR组）和118例慢性持续性HBV感染者[包括无症状HBV携带者（AsC组）36例和进展性肝病者82例（慢性乙型肝炎50例、乙肝后肝硬化32例）]的IFN-γ基因＋874 T→A、＋2109 A→G两个位点的多态性，比较各组间基因型和等位基因频率。结果：①＋874 T→A位点多态性中，慢性持续性感染者总从基因型频率比SR组显著升高（P〈0．05），差异有显著性。等位基因A的频率，进展性肝病组均显著高于SR组（P〈0．05）。②＋2109 A→G位点多态性中，进展性肝病组总GG基因型显著高于SR组（P〈0．05），而肝硬化和慢乙肝组之间，SR和AsC组之间差别无显著性。结论：IFN-γ基因＋874 T→A、＋2109 A→G两个位点的多态性，与HBV感染不同结局之间有关，携带＋874 T→A从基因型和A等位基因的HBV感染者容易发展为慢性，A等位基因更趋向于进展性肝病，而携带＋2109 A→GGG基因型患者则容易进展为慢性乙型肝炎甚至肝硬化。     

HBV亚基因型B和C体外重组中间体的检测

目的:检测HBV亚基因型B和C的体外重组中间体.方法:将基因型B和C序列插入载体Plenti6/V5-D-topo-X后,共转染HepG2细胞,克隆,测定转染后HBV的核酸序列,而后用软件包RDP3Beta40进行序列比对.结果:发现存在3种重组中间体,重组中间体的重组位置为1740-1838至2443-2485.R1...     

Hepatitis B virus S gene mutants in infants infected despite immunoprophylaxis

Objective　To assess the correlation between hepatitis B virus (HBV) surface gene mutant infection and hepatitis B (HB) vaccination failure. Methods　Using sera from 106 infants who were born to HBV carrier mothers and failed in HB immunoprophylaxis, HBV S gene was amplified by PCR, transferred to nylon membranes for Southern blots, and then hybridized with oligonucleotide probes. Eleven of non-hybridizing samples were used for DNA sequencing. Results　93.4% (99/106) of the samples were HBV DNA positive, and 30.3% (30/99) failed to hybridize with at least one of the four probes. DNA sequencing confirmed that 10 of the 11 samples had an S gene mutation with amino acid (aa) change. The identified mutants included nucleotide (nt) 546T→A(aa131N→T), nt531T→C (aa126I→T), nt491A→C (aa113T→P), nt491T→A (aa113S→T), nt533C→A (aa127P→T), nt581T→A (aa143S→T), nt636A→T (aa161Y→F), and nt679A→C (aa175L→F). The sequence in one mother-infant pair was completely the same, with mutations at aa131 and aa161. Conclusions　The prevalence of HBV surface mutants is about 30% in the children failing in HB vaccination. HBV mutants can infect infants by maternal-infant transmission.     

Relation between hepatitis B virus genotypes and gene mutation of basic core promoter in Li nationality

Objective:To investigate the relation between hepatitis B virus(HBV) genotypes and the double mutation of A-to-T nucleotide(nt) 1762 and G-to-A nt 1764 in basic core promoter(BCP T1762/A1764) in patients of the Li nationality. Methods:Subjects were 125 HBV DNA positive patients that belong to the Li nationality on Hainan Island. HBV DNA genotype was determined by real time fluorimetry polymerase chain reaction. BCP T1762/A1764 mutation was performed using the direct sequencing method. Results:The prevalence rates of genotype B, genotype C, genotype D, genotype C and D mixed infection(genotype C＋D) and genotype B and D mixed infection (genotype B＋C) were 31.20%, 53.60%, 12.00%, 2.40% and 0.80% respectively. Mutation frequencies in patients infected with HBV genotype C(58.21%) were significantly higher than in those infected with other genotypes (P ＜0.01). The serum viral load of the patients with genotype C(5.74±1.21) was also higher than that of those with genotype B(P ＜0.01). Conclusion:The major genotypes in the Li nationality were genotype C and genotype B. The infection of genotype D and mixed infection also occurred in the Li nationality. Genotype C HBV has a higher replication rate, and the different degrees of pathogenecity among HBV genotypes may be related to BCP T1762/A1764 mutation frequency.     

RANTES gene single nucleotide polymorphisms and expression in patients with chronic hepatitis B virus infection

Background Regulated on activation, normal T-cell expressed and secreted (RANTES) plays a critical role in T-lymphocyte activation and proliferation. The process is involved in both acute and chronic phases of inflammation. The present study was to ascertain the possible correlations between chronic hepatitis B virus (HBV) infection and the RANTES gene polymorphisms and their expression. Methods The study included 130 HBV negative healthy donors and 152 patients with chronic hepatitis B (CHB) virus infection. The polymerase chain reaction (PCR) and restriction fragment length polymorphisms (RFLPs) were used to detect RANTES gene single nucleotide polymorphisms (SNPs). RANTES levels in the platelet depleted plasma were detected by enzyme linked immunosorbent assay (ELISA). Results RANTES alleles -403G, -28C and In1.1T were the predominant alleles in the subjects studied. No significant correlation was found between CHB infection and the RANTES alleles, while a significant correlation was found between CHB infection and increased RANTES expression in platelet depleted plasma (P<0.05). Conclusions SNPs in RANTES gene do not affect chronic HBV infection or the outcome of interferon-α treatment in patients positive for HBV “e” antigen (HBeAg+). However, patients with CHB infection express the higher levels of plasma RANTES, which is thus associated with CHB infection.     

TGF-β1基因多态性与乙型肝炎肝硬化的相关性研究

目的探讨转化生长因子-β1（TGF-β1）基因多态性是否与慢性HBV感染人群肝硬化发生的遗传易感相关。方法收集173例中国汉族慢性HBV感染患者（肝硬化组42例和非肝硬化组131例）和52例健康对照者的外周血标本,提取白细胞DNA,基因直接测序法检测TGF-β1基因4个多态性（869T/C、915G/C、-800 G/A、-509 C/T）,ELISA法检测TGF-β1血清浓度,比较各组TGF-β1基因型分布频率、等位基因频率及TGF-β1血清水平的差异。结果 （1）乙型肝炎肝硬化组TGF-β1869位点以TT基因型为主（47.6%）,高于非肝硬化组（25.2%）和对照组（19.2%）,差异有统计学意义（P〈0.05）;869T等位基因频率（63.1%）明显高于正常对照组（44.2%）,差异有统计学意义（P〈0.05）,乙型肝炎肝硬化组与慢性HBV感染非肝硬化组（53.8%）、慢性HBV感染非肝硬化组与正常组869T等位基因携带率相比,差异无统计学意义（P〉0.05）。（2）所检其余多态性位点基因型及基因频率未见组间统计学差异。（3）869T/C不同基因型患者的血清TGF-β1水平不一,T/T型携带者较T/C和C/C型可见明显增高（P〈0.017）。结论 TGF-β1869T可能与汉族人群乙型肝炎肝硬化的遗传易感相关,其机制可能与该多态性对TGF-β1血清水平的影响有关。     

乙型肝炎病毒基因多态性检测芯片的临床应用

目的:评价临床应用乙型肝炎病毒(HBV)基因多态性芯片(中科院上海微系统和信息技术研究所等研制),检测HBV基因前C区1896、1814,基本C区启动子(BCP)1762和1764,P区的YMDD基序552位等的点突变的效能。方法:以该芯片检测49例不同临床类型乙型肝炎病人血清,并对部分血清的PCR扩增产物进行测序分析。结果:HBV前C区1896位在血清HBeAg阳性病例中,野生株、混合(野生/突变)株、突变株和未确定(无杂交信号)的检出率,分别为57.7％,38.5％,0和3.8％;血清抗HBe阳性病例中,相应为33.3％,22.2％,33.3％和11％,后者突变株显著高于前者(P<0.01)。所有病例HBV前C区的1814位均为野生,未检出突变。BCP 1762和1764双突变在慢性重型肝炎和肝炎肝硬化的检出率分别为66.7％和69.2％,显著高于慢性肝炎的19%(P<0.01)。10例拉米夫定治疗6月以上,HBV DNA仍阳性者中,7例检出P区YIDD或YVDD突变,1例兼有YIDD和YVDD突变,余2例无杂交信号。7例1 896,4例BCP,6例YMDD的测序和芯片检测结果一致,6例无信号位点的测序结果显示,这些位点附近,出现了与杂交探针错配的突变。结论:初步结果提示,该芯片适用于临床检测HBV前C区、P区一些已知热点的突变,并可用于研究这些突变与疾病严重性,及产生抗HBV药物耐药间的相互关系。     

T3098C and T53C Mutations of HBV Genotype C Is Associated with HBV Infection Progress1

Objective To analyze the association between mutation(s) in preS region of HBV and hepatitis B disease progress in Chinese patients with genotype C chronic HBV infection. Methods Ninety-three patients with chronic genotype C HBV infection, including 24 asymptomatic carriers (ASC), 26 patients with chronic hepatitis B (CHB), 22 patients with liver cirrhosis (LC) and 21 HCC patients were investigated. Levels of HBV DNA, HBeAg, alanine aminotransferase (ALT), asparate transaminase (AST) were measured. HBV preS region was analyzed by PCR direct sequencing. Results The prevalence of lareS T3098C and T53C mutations of genotype C HBV was significantly higher in LC and HCC patients than ASC and CHB patients. The rate of T3098C mutation in ASC, CHB, LC, and HCC patients were 0.00% (0/24), 3.85% (1/26), 9.09% (2/22),and 30.77% (8/22), respectively (P=-0.0015), while the rate of T53C mutation was 12.50% (3/24), 3.85% (1/26), 40.91% (9/22),and 42.31% (11/26), respectively (P=0.0012). Conclusion The frequency of genotype C HBV preS T3098C and T53Cmutations is associated with hepatitis B infection progression.