反义寡核苷酸抗乙型肝炎病毒表达诱导凋亡的体外研究

目的：研究反义脱氧寡核苷酸（ASON）抗乙型肝炎病毒（HBV）复制表达的作用。方法：设计合成针对HBV PreS2的ASON并设非互补序列作对照,以人肝癌细胞系2.2.15细胞为细胞模型,应用ELISA观察了ASON对HBV基因表达的抑制作用,流式细胞仪观察了ASON对宿主细胞凋亡和增殖的影响。应用RIA法和MTT法观察ASON对细胞代谢的影响。结果：ASON可有效地抑制HBV基因的表达,对HBsAg和HBeAg的抑制率分别为66%和91%,而非互补序列对照无抑制作用：ASON可诱导宿主细胞凋亡,用药后第3天和第6天凋亡率分别为6.10%和6.43%,增殖指数分别为37%和36%,RIA和MTT法表明ASON对宿主细胞无细胞毒性作用。结论：ASON不仅以序列特异性方式发挥抗病毒作用,而且可能以凋亡的方式清除HBV。     

三螺旋形成寡核苷酸抑制乙型肝炎病毒复制及抗原合成的实验研究

目的 探讨三螺旋形成寡核苷酸抗乙型肝炎病毒（ＨＢＶ）作用。方法 针对ＨＢＶ核心启动子ＳＰ１位点,合成２１ｍｅｒ硫代磷酸三螺旋形成寡核苷酸及２１ｍｅｒ无关对照寡核苷酸。采用ＬＥＩＳＡ,斑点杂交法分别检测了经寡核苷酸处理的ＨｅｐＧ２．２．１５细胞及空白对照组细胞培养上清ＨＢｓＡｇ,ＨＢｅＡｇ及ＨＢＶ ＤＮＡ水平。结果 ＴＦＯ２１组２．２．１５细胞ＨＢｓＡｇ及ＨＢＶ ＤＮＡ分泌量明显低于空白对照组。ＴＦ     

HepG2与HepG2．2．15细胞中P53表达及细胞生物学活性的差异

目的观察HBV对肝癌细胞生物学活性的影响，探讨HBV导致原发性肝癌发生的机制。方法用Western blot方法检测HepG2细胞以及稳定转染了HBV质粒的HepG2．2．15细胞中P53蛋白的表达情况，观察二种细胞某些生物学活性，如细胞周期、细胞凋亡的差异及细胞生长曲线以及裸鼠成瘤情况。结果HepG2．2．15细胞中P53蛋白表达水平及细胞凋亡率均高于HepG2细胞，细胞周期检测发现处于“S”期的细胞HepG2．2．15多于HepG2，细胞生长曲线显示其生长速度快于HepG2细胞，并且具有成瘤性。结论HBV在细胞内复制对细胞的凋亡与增殖均具有增强作用，其对细胞凋亡的促进作用可能通过使P53稳定性增强，进而使其活性增强。HBV感染的细胞存在凋亡与增殖的抗衡，当细胞增殖占优势时，则易于生成肿瘤。     

Inhibition of hepatitis B virus by retroviral vectors expressing antisense RNA

Two retroviral vectors carrying an antisense gene from the hepatitis B virus (HBV) preS/S or preC/C were constructed and used to infect the human hepatoblastoma cell line 2.2.15, which expresses HBV surface antigen (HBsAg), HBV e antigen (HBeAg) and releases HBV particles. The results showed that the inhibitory effects of antisense gene transfer, mediated by retroviral vectors on the expression of HBV antigens, appeared as early as day 3 after transduction, reached a maximum on day 5 and persisted for at least 11 days. Our data indicate that, on day 5 after introduction, antisense preS/S inhibited HBsAg and HBeAg expression by 71% and 23%, and the antisense preC/C inhibited HBsAg and HBeAg expression by 23% and 59%. HBV DNA production, in the supernatant of the 2.2.15 cells transduced with either antisense preS/S or preC/C, was also reduced on day 5, but the viability of the 2.2.15 cells was not affected. Our results demonstrate that the replication and expression of HBV can be inhibited through antisense gene transfer mediated by retroviral vectors and that the antisense-preC/C or antisense-preS/S may be potentially useful for clinical gene therapy against HBV.     

Antisense oligonucleotide targeting at the initiator of hTERT arrests growth of hepatoma cells

AIM:To evaluate the inhibitory effect of antisense phosphorothioate oligonucleotide (asON) complementary to the initiator of human telomerase catalytic subunit (hTERT) on the growth of hepatoma cells.METHODS:The as-hTERT was synthesized by using a DNA synthesizer. HepG2.2.15 cells were treated with ashTERT at the concentration of 10μmol/L. After 72h, these cells were obtained for detecting growth inhibition,telomerase activity using the methods of MTT,TRAP-PCR-ELISA, respectively. BALB/c(nu/nu) mice were injected HepG2.2.15 cells and a human-nude mice model was obtained. There were three groups for anti-tumor activity study. Once tumors were established, these animals in the first group were administered as-hTERT and saline.Apoptosis of tumor cells was detected by FCM. In the 2nd group, the animals were injected HepG2.2.15 cells together with as-hTERT. In the third group, the animals were given as-hTERT 24 hours postinjection of HepG2.2.15 cells. The anti-HBV effects were assayed with ELISA in vitro and in vivo.RESULTS: Growth inhibition was observed in cells treated with as-hTERT in vitro. A significant different in the value of A570-A630 was found between cells treated with as-hTERT and control (P<0.01) by MTT method. The telomerase activity of tumor cells treated with as-hTERT was reduced,the value of A4so nm was 0.42 compared to control (1.49) with TRAP-PCR-ELISA. The peak of apoptosis in tumor cells given as-hTERT was 21.12%, but not seen in saline-treated control. A prolonged period of carcinogenesis was observed in the second and third group animals. There was inhibitory effect on the expression of HBsAg and HBeAg in vivo and in vitro.CONCLUSION: As-hTERT has an anti-tumor activity, which may be useful for gene therapy of tumors.     

甲胎蛋白启动子介导反义乙型肝炎病毒X基因在肝癌细胞中的表达及其作用

目的 构建含甲胎蛋白(AFP)启动子和增强子的反义乙型肝炎病毒X基因(HBX)真核表达载体，研究其特异性和有效性，为开发肝癌细胞特异性HBX反义RNA基因治疗乙型肝炎病毒(HBV)奠定基础。方法 聚合酶链反应(PCR)扩增HBX(1370—1872nt)基因，克隆至EB病毒表达载体，双轮PCR筛选、鉴定基因插入方向。脂质体转染肝癌细胞和ECV304细胞，Northernblot检测HBX mRNA的表达，酶联免疫试验(ELISA)检测HBV抗原，荧光定量PCR检测HBV DNA。结果 成功构建正、反义RNA表达载体pEBAF—s—HBX、pEBAF—as—HBX。Northernblot证实反义RNA仅在AFP阳性的肝癌细胞中表达。pEBAF—as—HBX转染3d后，可显著抑制2．2．15细胞HBV复制和抗原表达，其HBsAg、HBeAg抗原表达较正义对照分别下降37．9％和36．8％，HBV DNA降低25％。结论 反义RNA表达载体pEBAF—as—HBX仅在肝癌细胞中特异表达、并可有效抑制HBV，有良好的开发应用前景。     

A novel HBV antisense RNA gene delivery system targeting hepatocellular carcinoma

AIM: To construct a novel HBV antisense RNA delivery system targeting hapatocellular carcinoma and study its inhibitory effect in vitro and in vivo.METHODS: GE7,a 16-peptide specific to EGFR, and HA20,a homologue of N-terminus of haemagglutinin of influenza viral envelope protein, were synthesized and conjugated with polylysin. The above conjugates were organized into the pEBAF-as-preS2, a hepatocarcinoma specific HBV antisense expression vector, to construct a novel HBV antisense RNA delivery system, named AFP-enhancing 4-element complex. Hepatocelluar carcinoma HepG2.2.15 cells was used to assay the in vitro inhibition of the complex on HBV. Expression of HBV antigen was assayed by ELISA.BALB/c nude mice bearing HepG2.2.15 cells were injected with AFP-enhancing 4-element complex. The expression of HBV antisense RNA was examined by RT-PCR and the size of tumor in nude mice were measured.RESULTS: The AFP-enhancing 4-element complex was constructed and DNA was completely trapped at the slot with no DNA migration when the ratio of polypeptide to plasmid was 1:1.The expression of HBsAg and HBeAg of HepG2.2.15 cells was greatly decreased after being transfected by AFP-enhancing 4-element complex. The inhibitory rates were 33.4 % and 58.5 % respectively. RT-PCR showed HBV antisense RNA expressed specifically in liver tumor cells of tumor-bearing nude mice. After 4 injections of AFP-enhancing 4-element complex containing 0.2 μg DNA, the diameter of the tumor was 0.995 cm±0.35,which was significantly smaller than that of the control groups (2.215 cm±025, P<0.05).CONCLUSION: AFP-enhancing 4-element complex could deliver HBV antisense RNA targeting on hepatocarcinoma and inhibit both HBV and liver tumor cells in vitro and in vivo.     

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.     

槲芪癥消汤对人肝癌细胞株HepG2.2.15增殖和凋亡的影响

目的:研究槲芪癥消汤对体外培养的人肝癌细胞株HepG2.2.15的增殖、凋亡、迁移能力、细胞内p53基因及蛋白表达量的影响,揭示该方可能的抗肿瘤机制。方法:应用不同浓度的槲芪癥消汤处理细胞,MTT法测定细胞增殖抑制率,Transwell检测细胞侵袭能力、流式细胞术检测细胞凋亡情况、rt-qPCR及Western blot检测细胞内p53的RNA及蛋白的表达变化。结果:槲芪癥消汤对HepG2.2.15细胞增殖有明显的抑制作用,使细胞的侵袭能力明显下降,并可促进细胞凋亡,同时细胞内p53的RNA及蛋白表达量明显增加,与对照组比较,差异均有统计学意义(均P<0.05)。结论:槲芪癥消汤能抑制肝癌HepG2.2.15细胞的增殖、侵袭,促进其凋亡,可能与促进细胞内的p53基因表达有关。     

核定位信号突变型P21真核表达载体的构建及其对HepG2.2.15细胞病毒复制的影响

目的构建核定位信号突变型P21基因的真核表达载体并初步探讨其对HBV复制的影响。方法采用基因定点诱变技术突变P21基因的核定位信号序列,采用DNA重组技术,亚克隆突变型P21基因至pDsRed1-C1真核表达载体中,重组为pDsRed1-C1-p21NLS-,酶切鉴定及DNA测序,脂质体转染HepG2.2.15细胞,RT-PCR检测目的基因pDsRed1-C1-p21NLS-的表达,荧光显微镜观测目的基因亚细胞定位,ELISA法检测培养上清液中HBsAg、HBeAg的水平。结果 pDsRed1-C1-p21NLS-质粒构建成功,与野生型相比,主要在胞浆表达,促进病毒的复制。二者差异有统计学意义（P〈0.01）。结论 P21的亚细胞定位,对HepG2.2.15细胞中病毒复制的影响具有明显差异。胞核P21抑制病毒的复制,而胞浆P21促进病毒复制。     

Sequencing of PCR amplified HBV DNA pre-c and c regions in the 2.2.15 cells and antiviral action by targeted antisense oligonucleotide directed against sequence

AIM:To study the specific inhibition of HBV gene expression by liver-targeting antisense oligonucleotide (ASON) directed against pre-c and cregious in a sequence specific manner.METHODS:According to the result of direct sequencing of PCR amplified products, a 16 mer phosphorothioate analogue of the antisense oligonucleotide (PS-ASOn) directed against the HBV U-5-like region was synthesized and then linked with one live-targeting ligand, the galactosylated poly-L-lysine.Their effect on the expression of HBV gene was observed using the 2.2.15 cells.RESULTS:HBV DNA in the 2.2.15 cells was from HBV with surface antigen subtype ayw 1 by sequencing so that antisense oligonucleotides could bind specifically to the target sequence through base piring. Under the same experimental conditions, the inhibitory rates of PS-ASON to HBsAg and HBeAg were 70% and 58% at a concentration of 10&mgr;mol/L, while by ligand-PS-ASON they were 96% and 82%, the amount of HBV DNA in cultured supernatant and cells was reduced significantly. An unrelated sequence oligonucleotide showed no effectiveness. All the oligonucleotides had no cytotoxicity.CONCLUSION:Antisense oligonucleotides complexed by the liver-targeting ligand can be targeted to cells via asialoglycoprotein receptors, resulting in supecific inhibition of HBV gene expression and replication.     

Sequencing of PCR amplified HBV DNA pre-c and c regions in the 2.2.15 cells and antiviral action by targeted antisense oligonucleotide directed against the sequence

AIM To study the specific inhibition of HBV gene expression by liver-targeting antisense oligonucleotide (ASON) directed against pre-c and c regious in a sequence-specific manner.METHODS According to the result of direct sequencing of PCR amplified products, a 16-mer phosphorothioate analogue of the antisense oligonucleotide (PS-ASOn) directed against the HBV U5-like region was synthesized and then linked with one live-targeting ligand, the galactosylated poly-L-lysine. Their effect on the expression of HBV gene was observed using the 2.2.15 cells.RESULTS HBV DNA in the 2.2.15 cells was from HBV with surface antigen subtype ayw1 by sequencing so that antisense oligonucleotides could bind specifically to the target sequence through base piring. Under the same experimental conditions, the inhibitory rates of PS-ASON to HBsAg and HBeAg were 70% and 58% at a concentration of 10μmol/L, while by ligand-PS-ASON they were 96% and 82%, the amount of HBV DNA in cultured supernatant and cells was reduced significantly. An unrelated sequence oligonucleotide showed no effectiveness. All the oligonucleotides had no cytotoxicity.CONCLUSION Antisense oligonucleotides complexed by the liver-targeting ligand can be targeted to cells via asialoglycoprotein receptors, resulting in supecific inhibition of HBV gene expression and replication.     

In vivo inhibition of hepatitis B viral gene expression by antisense phosphorothioate oligodeoxynucleotides in athymic nude mice

SUMMARY. Antisense oligodeoxynucleotides strategies have been used both to study normal gene function and to block gene expression therapeutically. We have previously shown that a number of antisense oligonu-cleotides against hepatitis B virus (HBV) mRNA are able to inhibit viral gene expression in vitro. Here we report the establishment of an animal model producing HBV markers in athymic nude mice and inhibition of HBV gene expression and replication by antisense DNA in vivo. 2.2.15 cells (Hep-G2 cell line transfected with HBV genomes) were injected subcutaneously (s.c.) into athymic BALB/c nude mice at a total cell number of 0.5–1×10⁸ per mouse. Transplanted tumours developed about 2 weeks after inoculation. Hepatitis B surface and e antigens (HBsAg and HBeAg), as well as HBV DNA, could be detected in the circulation of tumour-bearing mice. Hepatitis B surface antigen and hepatitis B core antigen (HBcAg) were demonstrated in tumour cells. After 10 days of tumour growth, antisense phosphorothioate oligonucleo-tide, complementary to the cap site of the SPII promoter of HBV mRNA, were injected by infiltration into or around the tumour as a daily dose of 20 μg per gram body weight. Treatment for a total of 10 days resulted in an effective inhibition of viral replication and gene expression. These results suggest therapeutic potential for antisense oligomers in the treatment of patients who are chronically infected with HBV.     

反义锁核酸与拉米夫定在HepG2.2.15细胞中抗HBV作用的比较

目的:应用反义锁核酸与拉米夫定作用HepG2.2.15细胞,对他们抗乙型肝炎病毒(hepatitis B virus,HBV)效果进行比较.方法:设计针对HBV翻译起始区S基因mRNA的反义寡核苷酸,并进行锁核酸修饰,以阳离子脂质体介导反义锁核酸转染HepG2.2.15细胞;拉米夫定组直接作用HepG2.2.15细胞;分别于用药后第2、4、6、8、10天收集细胞培养上清液.用ELISA法和FQ-PCR法检测收集上清液HBsAg、HBeAg和HBVDNA的含量.MTT法分别检测反义锁核酸与拉米夫定对细胞存活率的影响.结果:拉米夫定对HBVDNA具有明显抑制作用,最高可达46.52%,但对HBsAg、HBeAg影响较小;反义锁核酸对HBsAg、HBeAg及HBVDNA均有较强抑制作用,对HBsAg、HBeAg和HBVDNA的最高抑制率分别达67.69%、59.71%和62.96%(P<0.05),且抑制随时间呈增高趋势.反义锁核酸与拉米夫定对细胞代谢均无明显影响.结论:反义锁核酸抗HBV作用机制与拉米夫定不同,反义锁核酸抗HBV作用明显优于拉米夫定.     

Increased apoptosis in HepG2.2.15 cells with hepatitis B virus expression by synergistic induction of interferon‐γ and tumour necrosis factor‐α

Background: Interferon‐γ (IFN‐γ) and tumour necrosis factor‐α (TNF‐α) were thought to be important immune mediators in host defence against hepatitis B virus (HBV) infection. Aims: To examine the synergistic effect of IFN‐γ and TNF‐α on HBV‐expressing HepG2.2.15 cells and its potential mechanisms. Methods: Cell viability was quantitatively measured by 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyl tetrazolium bromide assay. Cell morphology was captured using light microscopy. The typical DNA ladder test was performed using agarose gel electrophoresis. HBsAg and HBeAg titre changes were quantified by the enzyme‐linked immunosorbent assay method. Gene expression was analysed using cDNA macroarrays. Results: Interferon‐γ (1000 U/ml) alone or combined with TNF‐α (5 ng/ml) treatment resulted in apoptosis in HepG2.2.15 cells, but no significant apoptosis in the parent non‐virus expressing HepG2 cells. IFN‐γ‐ and TNF‐α‐mediated apoptosis was reduced by lamivudine treatment in HepG2.2.15 cells. IFN‐γ combined with TNF‐α reduced the titre of hepatitis B surface antigen and hepatitis B e antigen in the HepG2.2.15 cell line. For apoptosis‐related gene changes, IFN regulatory factor 1 (IRF‐1) (12.2‐fold), c‐myc (V00568 4.7‐fold, L00058 2.4‐fold) and caspase 7 (2.3‐fold) genes were upregulated in the combination treatment group. Conclusion: Interferon‐γ and TNF‐α play a role in the cell death of HBV‐expressing HepG2.2.15 cells. Expression of HBV leads to IFN‐γ‐ and TNF‐α‐mediated apoptosis in the cells. Increased IRF‐1, c‐myc and caspase 7 gene expression may be responsible for the synergistic induction of apoptosis by IFN‐γ and TNF‐α.     

长片段RNA抑制HepG2.2.15细胞中HBV基因的表达和复制

目的 评估长的反义RNA干扰片段在培养细胞株中对HBV复制的抑制效应.方法将HBV基因组S区的全部核苷酸序列插入至pTARGETTM载体中,并将重组载体转染入HepG2.2.15细胞中.用酶联免疫吸附法检测HBsAg与HBeAg水平,用荧光定量PCR法检测HBVDNA水平.对数据采用多个独立样本Kruskal-Wallis检验与两两比较的Mann-Whitney U检验.结果 经过处理后,HepG2.2.15细胞上清液中HBsAg表达量(A值)在HBS2组(携带长片段反义RNA)为0.621±0.027,在HBS4组(携带正义RNA)为3.399±0.018,对照组为2.232±0.187;HBeAg表达量(A值)在HBS2组、HBS4组和对照组分别为0.749±0.019、1.548±0.025和1.570±0.044; HBV DNA水平(×104拷贝/ml)在HBS2组、HBS4组、对照组分别为1.597±0.082、3.381±0.297和3.610±0.063.与对照组相比,HBS2组HBsAg、HBeAg和HBV DNA表达量均降低,统计量Z值均为-2.309,P值均＜0.05; HBS4组HBsAg表达量增高(Z=-2.309,P＜0.05),而HBeAg和HBV DNA表达量无明显差异,统计量Z值分别为-0.866、-1.155,P值均＞0.05.结论 长片段反义RNA能抑制HBV基因的表达和病毒复制.

Abstract：

Objective To evaluate the inhibitory effects of long antisense RNA on HBV replication in HepG2.2.15 cells. Methods The coding region of HBV S gene was cloned into pTARGET vector in sense and antisense orientations and the recombinant plasmids were transfected into HepG2.2.15 cells which were divided into HBS2 (antisense RNA) group, HBS4 (sense RNA) group and control group. HBsAg and HBeAg in the culture supernant were detected by ELISA. The HBV DNA in the supernant was quantified by real-time PCR. Results After treatment, the levels of HBsAg in HepG2.2.15 cell supernatants of three groups were 0.621 ± 0.027, 3.399 ± 0.018 and 2.232 ± 0.187 respectively; the levels of HBeAg were 0.749 ± 0.019,1.548 ± 0.025 and 1.570 ± 0.044 respectively and the levels of HBV DNA were 1.597 ± 0.082, 3.381 ± 0.297 and 3.610 ± 0.063 respectively. The expressions of HBsAg and HBeAg and the HBV DNA level in HBS2 group were remarkably reduced as compared to the control (Z = -2.309, P ＜ 0.05); whereas the sense plasmid transfection (HBS4) did not affect HBeAg (Z= -0.866) and HBV DNA (Z = -1.155) levels in the culture supernant but slightly increased the HBsAg level (Z = -2.309). Conclusion Antisense RNA might be a useful tool to repress HBV replication.     

HepG2与HepG2．2．15细胞中P53表达及活性的比较

目的探讨HBV对抑癌基因P53表达及活性的影响。方法选用HepG2及转染了HBV表达质粒的HepG2．2．15细胞，采用Western blotting法检测两种细胞P53的表达状况；磷酸钙法将报告基因质粒PG13-CAT和P21-LUC分别转染细胞，通过检测报告基因的表达观察各细胞中P53的活性。结果HepG2．2．15细胞中P53蛋白表达水平高于HepG2细胞，而且两种报告基因的表达在HepG2．2．15细胞中也较高。结论HBV在肝癌细胞内的复制对P53的表达及功能具有一定的增强作用。     

VP22 fusion protein-based dominant negative mutant can inhibit hepatitis B virus replication

AIM: To investigate the inhibitory effect of VP22 fusion protein-based dominant negative (DN) mutant on Hepatitis Bvrus (HBV) replication. METHODS: Full-length or truncated fragment of VP22 was fused to C terminal of HBV core protein (HBc), and subcloned into pcDNA3.1 (-) vector, yielding eukaryotic expression plasmids of DN mutant. After transfection into HepG2.2.15 cells, the expression of DN mutant was identified by immunofluorescence staining. The inhibitory effect of DN mutant on HBV replication was indexed as the supernatant HBsAg concentration determined by RIA and HBV-DNA content by fluorescent quantification-PCR (FQ-PCR). Meanwhile, metabolism of HepG2.2.15 cells was evaluated by MTT colorimetry. RESULTS: VP22-based DN mutants and its truncated fragment were expressed in HepG2.2.15 cells, and had no toxic effect on host cells. DN mutants could inhibit HBV replication and the transduction ability of mutant-bearing protein had a stronger inhibitory effect on HBV replication. DN mutants with full length of VP22 had the strongest inhibitory effect on HBV replication, reducing the HBsAg concentration by 81.94%, and the HBV-DNA content by 72.30%. MTT assay suggested that there were no significant differences in cell metabolic activity between the groups. CONCLUSION: VP22-based DN mutant can inhibit HBV replication effectively.     

HBV preS1反基因锁核酸的设计及体外对病毒复制的抑制

目的:探讨针对乙型肝炎病毒(hepatitis Bvirus,HBV)preS1 dsDNA同聚嘌呤区设计反基因锁核酸分子,并观察其在HepG2 2.2.15细胞内抑制病毒复制的效果.方法:针对HBVpreS1 dsDNA的2941-2962 nt、3 015-3 036 nt和3 089-3 110 nt三个同聚嘌呤区,利用RNA structure软件分别设计合成锁核酸、硫代寡核苷酸、未修饰寡核苷酸及无关对照序列,以阳离子脂质体介导转染HepG22.2.15细胞,采用荧光定量聚合酶链反应技术(FQ-PCR)和时间分辨免疫荧光技术(TRFIA)分别监测1、3、5和7 d细胞培养上清液中HBV DNA和HBsAg的含量;四甲基偶氮唑蓝(MTT)法检测锁核酸对细胞代谢的影响.结果:反基因锁核酸对细胞内的HBV DNA复制与HBsAg表达有明显的抑制作用,且抑制率随时间呈增高趋势,7 d后抑制率分别为64.32%和67.51%.各实验组与对照组比较差异均具有统计学意义(均P<0.05),而封闭2 941-2 962 nt同聚嘌呤靶区的LNA抑制作用最强,且最适序列长度为20-30 bp.LNA对细胞代谢无明显影响.结论:针对preS1 dsDNA同聚嘌呤区的反基因锁核酸分子,体外能有效抑制HBV的复制,以封闭2 941-2 962 nt靶位效果最强,且合适序列长度为20-30 bp.