HBV X基因-HCV C基因cDNA融合基因真核表达载体的构建及其表达

目的：构建HBV X-HCV C融合基因真核表达载体，并获得稳定表达该基因的HepG2细胞株。方法：双酶切质粒pXT1-X，得到完整的HBV X基因片段后，将其插入到质粒PBK-CMV和PBK-HCVC的相应酶切位点，得到重组质粒PBK-X和PBK-X-C；再将质粒RBK-CMV、PBK-X、PBK-HCV C和PBK-X-C分别导入肝癌细胞株HepG2中，G418筛选，RT-PCR、蛋白印迹鉴定HBV X和HCV C蛋白表达。结果：质粒PBK-CMV、PBK-X、PBK-HCV C和PBK-X-C在HepG2细胞中有稳定表达。结论：成功构建HBV X-HCVC融合基因真核表达载体，并获得稳定表达该基因的HepG2细胞株。     

乙型肝炎病毒X基因-丙型肝炎病毒C基因共表达对血管内皮细胞生长因子的影响

目的建立乙型肝炎病毒X基因-丙型肝炎病毒C基因（HBV X—HCV C）共表达HepG2细胞模型，并探讨其对血管内皮细胞生长因子表达的影响。方法双酶切质粒pXT1—X，得到完整的HBV X基因片段后，将其插入到质粒PBK—CMV和PBK—HCV C的相应酶切位点，得到重组质粒PBK—X和PBK—X—C；再将质粒PBK—CMV、PBK—X、PBK—HCV C和PBK—X—C分别导入肝癌细胞株HepG2中，G418筛选，逆转录聚合酶链反应、Western blot鉴定HBV X和HCV C蛋白表达，免疫组织化学、Western blot检测血管内皮细胞生长因子蛋白质表达。结果质粒PBK—CMV、PBK—X、PBK—HCV C和PBK—X—C在HepG2细胞中有稳定表达。共表达HBV X—HCV C蛋白的细胞血管内皮细胞生长因子蛋白质表达较转染空载体的细胞及单独表达HBV X、HCV C蛋白的细胞明显升高。结论HBV X—HCV C共表达能显著上调血管内皮细胞生长因子蛋白质表达，提示HBV、HCV可能具有协同致癌作用。     

乙型肝炎病毒X基因对痉挛性截瘫蛋白21表达的影响

目的 探讨HBV X基因对痉挛性截瘫蛋白(SPG)21表达的影响.方法 采用RT-PCR和Western blot检测HepG2和HepG2.2.15细胞mRNA和蛋白表达的差异,将带有SPG21基因启动子的报告质粒pGL3-SPG21分别与表达HBV基因组的单个基因的质粒共转染HepG2细胞,测定荧光色素酶的活性,以相对光单元(RUL)表达;RT-PCR和Western blot分别检测SPG21 mRNA和蛋白表达的变化.组间比较采用t检验.结果 HepG2.2.15细胞中SPG21 mRNA和蛋白的表达水平明显高于HepG2细胞,相对表达量(与β-肌动蛋白的灰度比值)为0.36±0.06对比0.21±0.05,P＜0.05.转染pCMV-S、pCMV-E、pCMV-C、pCMV-X、pCMV-P和pCMV-ag2B后的HepG2细胞中,荧光素酶的活性分别为每微克蛋白(86±12)RUL、(75±12)RUL、(69±11)RUL、(875±27)RUL、(104±16)RUL和(67±12)RUL;与转染pCMV-tag2B组细胞相比,转染X基因者荧光素酶活性明显升高(P＜0.01).HBV X基因在mRNA和蛋白水平上调SPG21的表达,这种激活作用随着X基因浓度的增加而增强.结论 HBV X基因能特异性地激活SPG21的表达.     

miRNA干扰质粒的构建及其对肝癌HepG2细胞IGF-Ⅱ表达的抑制作用

目的:研究miRNA干扰质粒对胰岛素样生长因子Ⅱ(IGF-Ⅱ)在肝细胞癌表达的抑制作用,探讨IGF-Ⅱ在肝细胞癌治疗中的价值.方法:以人IGF-Ⅱ基因序列设计并合成4条miRNA,将miRNAA插入质粒构建pcDNA<'TA>6.2-GW/EmGFP miR 1-4干扰载体;筛选、转染HepG2细胞,以荧光定量PCR分...     

丙型肝炎病毒核心蛋白激活肝癌细胞血管内皮生长因子的表达

目的 探讨丙型肝炎病毒（HCV）核心蛋白对肝瘤细胞血管内皮生长因子（vascular endothelial growth factor,VEGF)表达的影响。方法 将HCV核心基因cDNA插入真核表达载体PBK－CMV的Hind Ⅲ和BamH I位点间，构建重组质粒PBK－HCVc。再将重组质粒PBK－HCVc和空载体分别导入肝癌细胞株HepG2中，G418筛选，RT－PCR、蛋白印迹鉴定HCV核心蛋白表达。免疫组织化学，蛋白印迹检测VEGF蛋白表达；原位杂交，RT－PCR检测VEGF mRNA。结果 重组质粒PBK－HCVc在HepG2细胞中有稳定表达；表达HCV核心蛋白的细胞HepG2-C的VEGF在蛋白水平和mRNA水平较转染空载体的细胞HepG2-CMV明显升高。结论 HCV核心蛋白能激活VEGF表达，可能对肝细胞癌的生长具有促进作用。     

丙型肝炎病毒F蛋白反式激活蛋白2基因在酵母细胞中的表达

目的为探讨丙型肝炎病毒(HCV)F蛋白反式激活蛋白2(HCV FTP2)的功能,在真核生物酵母细胞中表达HCV FTP2基因.方法以HepG2细胞来源的mRNA作为模板,经过逆转录聚合酶链反应(RT-PCR)扩增HCV FFP2基因,克隆到pGEM-T载体中,双酶切后回收连接到酵母表达质粒pGBKT7中表达.提取酵母蛋白质,进行十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)和Western blot免疫印迹分析.结果成功构建HCV FTP2基因酵母表达载体,Western blot免疫印迹显示HCV FTP2基因在酵母细胞中表达成功.表达产物相对分子质量27kD.结论HCV FTP2在酵母中表达成功.     

慢病毒介导HBV X基因稳定表达HepG2细胞系的建立

目的:构建乙型肝炎病毒X基因(HBV X)重组慢病毒表达载体,建立稳定表达HBVX蛋白(HBx)的HepG2细胞系.方法:应用PCR法从质粒pIERES2-EGFP-HBV中扩增X基因片段,克隆至慢病毒载体pZac2.1,应用PCR、酶切和测序鉴定正确后,经病毒包装,感染HepG2细胞,经嘌呤霉素筛选稳定表达细胞株,RT-PCR、免疫组织化学、Western blot鉴定HBx的表达.结果:酶切鉴定和基因序列测定证实长度为489bp的HBx基因成功克隆至慢病毒表达载体pZac2.1-HBx;重组慢病毒经包装、纯化后获得滴度为1×108TU/mL,通过感染HepG2细胞株和嘌呤霉素筛选,8-10d形成生长形态良好的单克隆细胞株HepG2-HBx;RT-PCR鉴定显示细胞株HepG2-HBx在3d,14d,30d和2mo后均可见稳定表达的HBx mRNA;利用免疫组织化学和蛋白免疫印迹法鉴定,细胞株HepG2-HBx可稳定表达HBx蛋白.结论:成功构建了HBV X重组慢病毒载体,获得稳定表达HBx的HepG2细胞系,为进一步研究HBx的生物学功能及致病机制提供细胞模型.     

丙型肝炎病毒1b基因型核心蛋白对HepG2细胞Bax与Bcl-2基因表达的影响

目的研究丙型肝炎病毒（HCV）1b基因型核心蛋白（C）对HepG2细胞B细胞淋巴瘤-2基因（Bcl-2）与Bcl-2相关X蛋白（Bax）表达的影响,以探索1b型HCV C蛋白与HepG2细胞凋亡的关系。方法利用RT-PCR扩增出HCV-1b-C基因,经双酶切后连接pcDNA3.1（-）,成功构建真核表达载体pcDNA3.1（-）/HCV-1b-C。利用脂质体转染HepG2细胞,RT-PCR及Western Blot检测其mRNA及蛋白的表达,RT-PCR及Western Blot检测转染成功后HCV-1b-C对HepG2细胞Bax与Bcl-2表达的影响,并设转染空质粒组及未处理组作对照。结果成功构建真核表达载体pcDNA3.1（-）/HCV-1b-C;瞬时转染HepG2细胞,成功表达HCV C mRNA及蛋白;转染C基因组的Bax的mRNA及蛋白相对表达量减少,与转染空质粒组及未处理组比较差异均有统计学意义（P〈0.01）;转染C基因组的Bcl-2的mRNA及蛋白相对表达量增多,与转染空质粒组及未处理组比较差异均有统计学意义（P〈0.01）。结论 1b基因型HCV C蛋白转染HepG2细胞会导致Bax表达减少及Bcl-2表达增多,降低Bax/Bcl-2比值,可能是抑制HepG2细胞凋亡的机制之一。     

HBV pre-X转染HepG2细胞后差异表达基因的筛选

目的:检测HBV Pre-X在真核表达栽体PcDNA3.1-myc-his-HBV pre-X转染的HepG2细胞中的表达,并筛选其中的代谢相关差异表达基因.方法:将构建的真核表达载体pcDNA3.1-mychis-HBV pre-X转染HepG2细胞后蛋白免疫印迹检测:将pcDNA3.1-myc-his-HBV pre-X和pcDNA3.1-myc-his载体分别转染HepG2细胞后,提取mRNA后逆转录为cDNA,运用基因表达谱芯片技术分析差异表达基因.结果:构建的真核表达载体经ApsI、BstXI双酶切鉴定,转染HepG2细胞后HBV pre-X表达经蛋白免疫印迹证实:经基因表达谱芯片分析发现,其中基因表达水平显著上调和下调的分别是200个和62个.结论:筛选HBV pre-X转染HepG2细胞后的代谢相关差异表达基因,从而为乙型肝炎病毒合并糖尿病、脂肪肝等代谢性疾病的分子生物学机制的研究提供了重要依据.     

HCV核心基因转染HepG2细胞后基因表达差异筛选

目的将真核表达载体pcDNA3.1(-)HCV core转染到HepG2细胞,在HepG2细胞中表达HCV核心蛋白,并筛选其中的差异表达基因。方法将构建的真核表达载体pCDNA3.1(-)HCVcore转染HepG2细胞后进行蛋白免疫印迹检测;将pcDNA3.1(-)HCVcore和pcDNA3.1(-)载体分别转染HepG2细胞后,提取mRNA并逆转录为cDNA,运用基因表达谱芯片技术分析差异表达基因。结果构建的真核表达载体经双酶切鉴定;转染HepG2细胞后HCV核心蛋白表达经蛋白免疫印迹证实;经基因表达谱芯片分析发现,其中基因表达水平显著上调和下调的分别是181个和48个。结论筛选HCV核心基因转染HepG2细胞后的糖类和脂类物质代谢相关的差异表达基因,从而为丙型肝炎病毒合并糖尿病、脂肪肝等代谢性疾病的分子生物学机制的研究提供了重要依据。     

bcl-2 and immunoglobulin gene rearrangement in patients with hepatitis C virus infection

An association between chronic hepatitis C virus (HCV) infection and clonal proliferation of B cells, including B cell lymphoma, has recently been demonstrated. However, the mechanism of malignant transformation is still unknown. It has been shown that B cells from patients with type II mixed cryoglobulinaemia (MC), strongly express the antiapoptotic bcl-2 oncogene product. Therefore, we investigated a possible mechanism of lymphomagenesis, the occurrence of bcl-2 and immunoglobulin gene rearrangement (IgH) in HCV-infected patients. Three groups of patients were studied: (1) 44 patients with HCV and MC (anti-HCV and HCV RNA positive); (2) 59 patients with chronic HCV infection without MC; (3) 50 patients with chronic liver disease (CLD) not related to HCV infection. The t(14;18) translocation (MBR bcl-2-JH) and IgH rearrangement (FR3/JH) were detected by polymerase chain reaction (PCR) in peripheral mononuclear cells. bcl-2 translocation was detected in 17/44 (39%), 7/59 (12%) and in none of the patients of groups 1, 2 and 3 respectively (P < 0.01). Monoclonal IgH rearrangement was detected in 15/44 (34%), 5/59 (8.5%) and 2/50 (4%) patients of groups 1, 2 and 3 respectively (P < 0.05). HCV-infected patients had a higher prevalence of monoclonal IgH rearrangement and bcl-2 translocation than patients with CLD of other aetiologies. These data suggest that HCV may play a role in the multistep mechanism of lymphomagenesis by inducing clonal proliferation of B cells and inhibition of apoptosis.     

乙型肝炎病毒和丙型肝炎病毒对纤维连接蛋白基因表达的调节

乙型肝炎病毒(HBV)和丙型肝炎病毒(HCV)感染是病毒性肝炎的主要病原体，感染后引起慢性化的频率较高。在我国，HBV或HCV的感染也是肝硬化和肝细胞癌(HCC)发病的主要原因。纤维连接蛋白(Fibronectin，Fn)是一种存在于血液、体液及各种组织中的具有多种功能的糖蛋白，来源于肝细胞，枯否细胞和内皮细胞，通过与整合素结合调节细胞间的粘附、免疫、凝血和血小板的聚集^[1]，另外在肿瘤与纤维化的发展与发病机制中，Fn也起着重要的作用^[2]。     

反义寡脱氧核苷酸对丙型肝炎病毒基因表达的抑制作用

为了解丙型肝炎病毒（ＨＣＶ）基因调控方式、探索反义寡脱氧核苷酸对丙型肝炎病毒基因表达的体外抑制作用。构建了由ＨＣＶ５′非翻译区（５′ＵＴＲ）翻译启动报道基因－虫荧光素酶（ｌｕｃ）基因的真核表达载体；人工合成了针对ＨＣＶ５′ＵＴＲ及非结构蛋白５（ＮＳ５）区的反义寡脱氧核苷酸（ＯＤＮ）。借助脂质体将ＯＤＮ分别与所构建的载体一同转染人癌细胞系，短期培养后制备细胞提取液，以荧光发光法检测ｌｕｃ基因的表达．     

Similar hepatitis C virus RNA kinetics in HIV/hepatitis C virus monoinfected genotype 2 or 3 matched controls during hepatitis C virus combination therapy

We prospectively studied early hepatitis C virus kinetics and sustained virological response rates in HIV/HCV coinfected (n = 13) and HCV monoinfected matched controls (n = 26) with HCV genotype 2/3 treated with pegylated interferon (peg-IFN) alpha-2a 135 microg/week plus ribavirin 11 mg/kg daily during 24 weeks. No significant difference in HCV-RNA decay was seen at any time point during the initial 12 weeks of therapy. Sustained virological response was achieved in 9/13 (69%) versus 20/26 (77%) patients (intent-to-treat), respectively. The lower-than-standard peg-IFN dose offered high compliance and reasonable sustained virological response rates.     

Production and pathogenicity of hepatitis C virus core gene products

Hepatitis C virus (HCV) is a major cause of chronic liver diseases, including steatosis, cirrhosis and hepatocellular carcinoma, and its infection is also associated with insulin resistance and type 2 diabetes mellitus. HCV, belonging to the Flaviviridae family, is a small enveloped virus whose positive-stranded RNA genome encoding a polyprotein. The HCV core protein is cleaved first at residue 191 by the host signal peptidase and further cleaved by the host signal peptide peptidase at about residue 177 to generate the mature core protein (a.a. 1-177) and the cleaved peptide (a.a. 178-191). Core protein could induce insulin resistance, steatosis and even hepatocellular carcinoma through various mechanisms. The peptide (a.a. 178-191) may play a role in the immune response. The polymorphism of this peptide is associated with the cellular lipid drop accumulation, contributing to steatosis development. In addition to the conventional open reading frame (ORF), in the +1 frame, an ORF overlaps with the core protein-coding sequence and encodes the alternative reading frame proteins (ARFP or core+1). ARFP/core+1/F protein could enhance hepatocyte growth and may regulate iron metabolism. In this review, we briefly summarized the current knowledge regarding the production of different core gene products and their roles in viral pathogenesis.     

Biological impact of hepatitis B virus X-hepatitis C virus core fusion gene on

AIM: To investigate the biological impact of hepatitis B virus X- hepatitis C virus core (HBV X-HCV C) fusion gene on hepatoma cells.METHODS: The recombinant adenoviruses AdXC,Ad-X and Ad-C expressing HBV X-HCV C fusion gene,HBVX gene and HCV C gene were constructed,respectively.Hepatoma cells were infected with different recombinant adenoviruses.MTT,colonyforming experiment,FCM,TUNEL assay were performed to observe the biological impact of the HBV X-HCV C fusion gene on liver cells.RESULTS: MTT showed that the Ad-XC group cells grew faster than the other group cells.Colony-forming experiment showed that the colony-forming rate for the Ad-XC group cells was significantly higher than that for the other group cells.FCM analysis showed that Ad-XC/Ad-X/Ad-C infection enhanced the progression of GIS phase in the HepG2 cell cycle.The apoptosis index of the Ad-XC,Ad-X,Ad-C group cells was significantly lower than that of the AdO and control group cells.Semi-quantitative RT-PCR showed that the expression level of c-myc was the highest in AdXC infected cells.Tumor formation was found at the injected site of mice inoculated with Ad-XC-infected LO2 cells,but not in control mice.CONCLUSION: Ad-XC,Ad-X and Ad-C facilitate the proliferation activity of HepG2 cells and inhibit their apoptosis in vitro.The effect of Ad-XC is significantly stronger than that of Ad-X and Ad-C.Up-regulation of c-myc may be one of the mechanisms underlying the synergism of HBVX and HCV C genes on hepatocarcinogenesis in athymic nude mice.