This work was supported in part by the Research Program on Hepatitis from Japan Agency for Medical Research and Development (AMED) and by Grants-in-Aids for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan.

1.生产重组乙型肝炎病毒的编码蛋白质记者<ol><li> HepG2细胞的制备 <ol><li>制备细胞培养基（Dulbecco改良的Eagle培养基（DMEM），补充有10％胎牛血清（FBS），100U / ml青霉素，100微克/毫升链霉素和100单位/毫升的非必需氨基酸）。 </li><li>板4×10 6个 HepG2细胞中在10ml培养基的转染前一天10厘米胶原包被的培养皿。孵育HepG2细胞于37℃在湿润的5％CO 2培养箱。 注意:当大约4×10 6个 HepG2细胞在10cm的胶原包被的培养皿铺板在10ml培养基中，它们将是70-90％汇合的第二天。 </li></ol></li><li> 转 <ol><li>转染HepG2细胞pUC1.2HBV增量小量15的5微克和pUC1.2HBV / NL 15 5微克使用染试剂根据制造商的说明。 </li><li>次日，除去培养基并加入10毫升的新鲜培养基。 </li><li>一周转染后，将含有重组乙肝培养基转移到50ml管，并进行到步骤1.3.1。 10毫升新鲜培养基添加到含转染的细胞的板。 注:重组乙肝病毒的产量保持4周。含有重组乙肝病毒的培养基可以储存在4℃下1个月。 </li></ol></li><li> 重组乙型肝炎病毒的分离纯化 <ol><li>从含有通过离心重组乙肝病毒（2300 xg离心5分钟）的培养基中除去细胞碎片。 </li><li>通过0.45μm膜过滤器传递上清液。 </li><li>的26％的PEG / 1.5 M氯化钠（聚乙二醇6000 130克，氯化钠49克，1 50ml的0.5M EDTA pH 8.0的和5ml的1M HEPES pH为7.6在500毫升）中加入等体积的培养基含重组HBV，轻轻混匀。在4℃孵育过夜。 </li><li>离心2300 XG在4℃下20分钟。 </li><li>弃去上清液并溶解沉淀在0.5ml TNE（10毫摩尔Tris，50mM NaCl中，1mM EDTA）中。 </li><li> 2,300 xg离心除去离心碎片5分钟。 </li><li>负载0.5毫升含重组乙肝TNE的拖到TNE0.8毫升20％的蔗糖。 </li><li>离心机在15℃100000×g下3小时。 </li><li>丢弃尽可能多上清尽可能的，并保存沉淀。悬浮它在1毫升每40 ml起始培养基的无血清DMEM中。 </li><li>在4℃孵育过夜。 </li><li>通过0.45微米的过滤器过滤。在-80℃制备各取一份0.5ml和存储。 注意:如果发现原来的病毒样本的记者蛋白污染，10万XG在TNE 5-30％的蔗糖密度梯度超离心纯化病毒2小时，或来回氯化铯密度离心平衡米1.1-1.6克/毫升15万XG为50小时。 </li></ol></li></ol> 2.重组乙肝病毒感染的<ol><li>培养HepG2细胞稳定表达NTCP（HepG2细胞/ NTCP）15易受HBV感染的DMEM补充有10％FBS，100U / ml青霉素，100微克/毫升链霉素，250微克/毫升的G-418和100U / ml的非必需氨基酸，在37℃在湿润的5％CO 2培养箱。 </li><li>感染前一天，板约5×10 4的HepG2 / NTCP细胞14进入在0.1ml培养基中的96孔胶原包被板。 </li><li>在37℃水浴解冻HBV重组，直到有剩余的小瓶冰小一点。 </li><li>由以下结合制备用于感染的培养基:在1×磷酸盐缓冲盐水（PBS），2微升二甲基亚砜（DMSO）中，加入10μl40％PEG8000的重组乙肝病毒的10微升和78微升新鲜培养基每一个96孔板的孔。 </li><li>加入100微升的重组乙肝病毒溶液的96孔板的一个孔中。 </li><li>感染后一天，洗净感染的细胞3次，用每孔300μl的PBS中，以从病毒级分除去的污染报告蛋白。 </li><li>孵育感染细胞在200μl含有2％DMS​​O的一周或更少的培养基。 </li></ol> 3.分析<ol><li>感染后一周，洗感染的细胞3次，用PBS。 </li><li>加入50μl裂解缓冲液的受感染的细胞。 </li><li>摇动培养板进行5分钟，然后在2000 xg离心离心5分钟。 </li><li>加入50微升记者基板进入光度计板。 </li><li>加入20μl的细胞裂解物与含记者基板光度计板。涡旋简要混合。 </li><li>放置在光度计板，并开始阅读15。 </li></ol>

<ol>
	<li>Fattovich, G., Stroffolini, T., Zagni, I., Donato, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hepatocellular+carcinoma+in+cirrhosis:+incidence+and+risk+factors.">Hepatocellular carcinoma in cirrhosis: incidence and risk factors.</a> Gastroenterology. 127 (5), 35-50 (2004).</li><li>Revill, P., Testoni, B., Locarnini, S., Zoulim, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Global+strategies+are+required+to+cure+and+eliminate+HBV+infection.">Global strategies are required to cure and eliminate HBV infection.</a> Nat. Rev. Gastroenterol. Hepatol. 13 (4), 239-248 (2016).</li><li>Wursthorn, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Peginterferon+alpha-2b+plus+adefovir+induce+strong+cccDNA+decline+and+HBsAg+reduction+in+patients+with+chronic+hepatitis+B.">Peginterferon alpha-2b plus adefovir induce strong cccDNA decline and HBsAg reduction in patients with chronic hepatitis B.</a> Hepatology. 44 (3), 675-684 (2006).</li><li>Stuyver, L. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nomenclature+for+antiviral-resistant+human+hepatitis+B+virus+mutations+in+the+polymerase+region.">Nomenclature for antiviral-resistant human hepatitis B virus mutations in the polymerase region.</a> Hepatology. 33 (3), 751-757 (2001).</li><li>Ochiya, T., Tsurimoto, T., Ueda, K., Okubo, K., Shiozawa, M., Matsubara, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+in+vitro+system+for+infection+with+hepatitis+B+virus+that+uses+primary+human+fetal+hepatocytes.">An in vitro system for infection with hepatitis B virus that uses primary human fetal hepatocytes.</a> Proc. Natl. Acad. Sci. USA. 86 (6), 1875-1879 (1989).</li><li>Galle, P. R., Hagelstein, J., Kommerell, B., Volkmann, M., Schranz, P., Zentgraf, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+experimental+infection+of+primary+human+hepatocytes+with+hepatitis+B+virus.">In vitro experimental infection of primary human hepatocytes with hepatitis B virus.</a> Gastroenterology. 106 (3), 664-673 (1994).</li><li>Gripon, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Infection+of+a+human+hepatoma+cell+line+by+hepatitis+B+virus.">Infection of a human hepatoma cell line by hepatitis B virus.</a> Proc. Natl. Acad. Sci. USA. 99 (24), 15655-15660 (2002).</li><li>Murakami, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Discovering+novel+direct+acting+antiviral+agents+for+HBV+using+in+silico+screening.">Discovering novel direct acting antiviral agents for HBV using in silico screening.</a> Biochem. Biophys. Res. Commun. 456 (1), 20-28 (2015).</li><li>Ladner, S. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inducible+expression+of+human+hepatitis+B+virus+(HBV)+in+stably+transfected+hepatoblastoma+cells:+a+novel+system+for+screening+potential+inhibitors+of+HBV+replication.">Inducible expression of human hepatitis B virus (HBV) in stably transfected hepatoblastoma cells: a novel system for screening potential inhibitors of HBV replication.</a> Antimicrob. Agents. Chemother. 41 (8), 1715-1720 (1997).</li><li>Yan, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sodium+taurocholate+cotransporting+polypeptide+is+a+functional+receptor+for+human+hepatitis+B+and+D+virus.">Sodium taurocholate cotransporting polypeptide is a functional receptor for human hepatitis B and D virus.</a> Elife. 3, (2012).</li><li>Wang, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Replication-competent+infectious+hepatitis+B+virus+vectors+carrying+substantially+sized+transgenes+by+redesigned+viral+polymerase+translation.">Replication-competent infectious hepatitis B virus vectors carrying substantially sized transgenes by redesigned viral polymerase translation.</a> PLoS. One. 8, 60306 (2013).</li><li>Chaisomchit, S., Tyrrell, D. L., Chang, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+replicative+and+nonreplicative+hepatitis+B+virus+vectors.">Development of replicative and nonreplicative hepatitis B virus vectors.</a> Gene. Ther. 4 (12), 1330-1340 (1997).</li><li>Hong, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+recombinant+hepatitis+B+virus+vectors+efficiently+deliver+protein+and+RNA+encoding+genes+into+primary+hepatocytes.">Novel recombinant hepatitis B virus vectors efficiently deliver protein and RNA encoding genes into primary hepatocytes.</a> J. Virol. 87 (12), 6615-6624 (2013).</li><li>Hall, M. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineered+luciferase+reporter+from+a+deep+sea+shrimp+utilizing+a+novel+imidazopyrazinone+substrate.">Engineered luciferase reporter from a deep sea shrimp utilizing a novel imidazopyrazinone substrate.</a> ACS. Chem. Biol. 7 (11), 1848-1857 (2012).</li><li>Nishitsuji, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+reporter+system+to+monitor+early+stages+of+the+hepatitis+B+virus+life+cycle.">Novel reporter system to monitor early stages of the hepatitis B virus life cycle.</a> Cancer. Sci. 106 (11), 1616-1624 (2015).</li><li>Sugiyama, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Influence+of+hepatitis+B+virus+genotypes+on+the+intra-+and+extracellular+expression+of+viral+DNA+and+antigens.">Influence of hepatitis B virus genotypes on the intra- and extracellular expression of viral DNA and antigens.</a> Hepatology. 44 (4), 915-924 (2006).</li><li>Seeger, C., Zoulim, F., Mason, W., Knipe, D., Howley, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hepadnaviruses.">Hepadnaviruses.</a> Field Virology. Volume 1. , 2185-2221 (2013).</li><li>Moolla, N., Kew, M., Arbuthnot, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulatory+elements+of+hepatitis+B+virus+transcription.">Regulatory elements of hepatitis B virus transcription.</a> J. Viral. Hepat. 9 (5), 323-331 (2002).</li><li>Cattaneo, R., Will, H., Schaller, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hepatitis+B+virus+transcription+in+the+infected+liver.">Hepatitis B virus transcription in the infected liver.</a> EMBO. J. 3 (9), 2191-2196 (1984).</li><li>Enders, G. H., Ganem, D., Varmus, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mapping+the+major+transcripts+of+ground+squirrel+hepatitis+virus:+the+presumptive+template+for+reverse+transcriptase+is+terminally+redundant.">Mapping the major transcripts of ground squirrel hepatitis virus: the presumptive template for reverse transcriptase is terminally redundant.</a> Cell. 42 (1), 297-308 (1985).</li><li>Haines, K. M., Loeb, D. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+sequence+of+the+RNA+primer+and+the+DNA+template+influence+the+initiation+of+plus-strand+DNA+synthesis+in+hepatitis+B+virus.">The sequence of the RNA primer and the DNA template influence the initiation of plus-strand DNA synthesis in hepatitis B virus.</a> J. Mol. Biol. 370 (3), 471-480 (2007).</li><li>Hirsch, R. C., Lavine, J. E., Chang, L. J., Varmus, H. E., Ganem, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polymerase+gene+products+of+hepatitis+B+viruses+are+required+for+genomic+RNA+packaging+as+well+as+for+reverse+transcription.">Polymerase gene products of hepatitis B viruses are required for genomic RNA packaging as well as for reverse transcription.</a> Nature. 344 (6266), 552-555 (1990).</li></ol>

The authors declare that they have no competing financial interests.

HBV基因组有四个主要的开放阅读框（ORFs），包括核心，聚合酶，表面和X的ORF（ 图1）。这四个HBV ORF的转录紧紧四个启动子调控:含有增强II的前核心/核心启动子，含有增强我18启动S1，S2启动子和X子。 3.5 kb和3.4 kb的mRNA的分别翻译成前C区和核心蛋白。大包膜蛋白（L）的从最大的亚基因组mRNA的（2.5kb的）产生的，而中间（M）和小的表面蛋白（S）是从短转录（2.1kb的）?...

乙型肝炎病毒（HBV）慢性感染是慢性肝病1的主要危险因素。虽然目前的治疗策略是基于抑制通过干扰素刺激基因功能2的HBV POL功能和/或激活在感染个体的免疫反应的I型干扰素的施用以及间接抑制HBV的增殖的核苷酸类似物，这些治疗不能消除HBV的DNA完全3。而且，对防聚合酶剂耐药HBVS的出现是关注4。合并的抗病毒剂直接针对人免疫缺陷病毒（HIV）或丙型肝炎病毒（HCV）的生命周期的不同步骤的管理被证明成功地抑制或根除病毒（ES）。类似这样的想法，即直接作用于H的不同阶段抗HBV剂的开发BV的生命周期是建立未来的乙肝治疗方法很重要。 在一般情况下，建立在目标病毒的体外培养系统中的简单的便于防病毒代理的发展。然而，有至少两个障碍的体外培养系统的发展，以筛选抗HBV剂。首先是缺乏一个方便的体外细胞培养HBV感染/扩散制度。不像其他的病毒，如HIV和HCV，其在建立的细胞系增殖，它是很难培养的HBV 体外因为实验的限制，包括一个窄的宿主范围的。使用具体的细胞培养系统，例如人肝癌细胞系HepaRG，这是易受HBV感染，5，6，7已经开发了克服了这些问题。此外，PXB的细胞，从尿激酶TY孤立PE纤溶酶原激活物的转基因/原发性人肝细胞（PHH）接种的SCID小鼠，被证明是容易受到HBV感染和复制8。然而，在HepaRG HBV复制的水平依赖于培养后的细胞的分化状态，这会导致HBV感染/复制水平的不一致和不可再现的结果。 PXB通常用于HBV感染实验，但是由它的可用性的限制。四环素诱导型HBV的表达细胞株，HepAD38，也被广泛用于研究HBV复制，但这种系统只允许转录后，而不是在HBV感染9的进入步骤评价。最近，牛磺胆酸钠cotransporting多肽的识别（NTCP）用作HBV的功能性受体已经允许可变的HBV培养系统10的开发。事实上，在非易感肝癌细胞如的Huh7 NTCP表达和肝癌使HBV感染10，因此，乙肝病毒易感细胞系的选择也不断扩大，解决许多实验的限制。第二个问题是缺少一种简单的测定系统来评估HBV感染和复制的。 HBV感染的评价通常是通过分析HBV DNA，RNA和蛋白质进行。但是，这些病毒标志物的定量是费时，常常是昂贵和不总是简单的。因此，一个简单的测定系统的发展，诸如使用报告基因，可能克服与HBV的测定系统相关的问题。 但是，因为可被包装成一个HBV衣壳基因组大小被限制-小于3.7 kb的11 -报告基因的大小应该尽可能地短。此外，分散在整个基因组中的多个顺式元件，其是病毒复制所必需的存在，限制了可用于在位置<html>报道基因到基因组中的插入可以。若干报告已经试图插入外源基因，包括HIV-1的Tat，绿色荧光蛋白，和红色荧光蛋白，成HBV基因组11，12，13。然而，这些重组HBVS不是用于筛选HBV感染/复制，或用于影响HBV感染/复制因子的高通量筛选是有用的。这主要是因为重组病毒的生产效率低而造成低效病毒产生报道基因表达的降低强度的。 为了克服这些问题，我们构建了记者乙肝病毒生产的高产率。这种病毒是用于监测HBV复制循环的早期阶段，从入口到转录高度敏感。为了实现这一目标，NanoLuc（NL）被选择作为标记基因，因为它是一个小的（171个氨基酸）工程改造发光报告类="外部参照"&gt; 14。另外，NL是约150倍萤火虫或Renilla荧光素酶亮，和发光反应是ATP的独立的，这表明假命中率将是低的为高通量筛选。重组乙肝病毒的生产效率为约1/5的父的HBV，和类似报告以前的HBV的重组病毒的水平;然而，NL的亮度克服病毒生产率的问题，因此它可以被用于抗HBV剂的大量筛选。 使用原代肝细胞的抗HBV剂的筛查，HepaRG，HepAD38和NTCP转导的肝细胞可能是抗HBV剂通过常规方法（多个）的筛选是有用的。然而，在这里所描述的系统具有各种优点，例如简单的处理，灵敏度高，且成本低的筛选。这些优势是适用于高通量分析制定和确定新HBV药物达到治疗目的。

<table border="0" cellpadding="0" cellspacing="0" width="781">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:332px;">Nano-Glo Luciferase Assay Regent</td>
			<td style="width:201px;">Promega</td>
			<td style="width:160px;">N1110</td>
			<td style="width:88px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Penicillin-Streptomycin Mixed Solution</td>
			<td>Nacalai tesque</td>
			<td>09367-34&#160;</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">MEM Non-Essential Amino Acids Solution</td>
			<td>Thermo Fisher Scientific</td>
			<td>11140050</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">DMEM</td>
			<td>Thermo Fisher Scientific</td>
			<td>11995065</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Opti-MEM I Reduced Serum Medium</td>
			<td>Thermo Fisher Scientific</td>
			<td>31985070</td>
			<td></td>
		</tr>
		<tr height="18">
			<td height="18" style="height:18px;width:332px;">100 mm/collagen-coated dish</td>
			<td>Iwaki</td>
			<td>4020-010</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Lipofectamine 3000 Transfection Reagent</td>
			<td>Thermo Fisher Scientific</td>
			<td>L3000001&#160;</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Polyethylene glycol (PEG) 6000&#160;</td>
			<td>Sigma-Aldrich</td>
			<td>81255</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Polyethylene glycol (PEG) 8000&#160;</td>
			<td>Sigma-Aldrich</td>
			<td>89510</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">NaCl</td>
			<td>Nacalai tesque</td>
			<td>31319-45&#160;</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">0.5 mol/l-EDTA Solution</td>
			<td>Nacalai tesque</td>
			<td>06894-14&#160;</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Tris-HCl</td>
			<td>Nacalai tesque</td>
			<td>35434-21</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Millex-HP, 0.45 &#956;m, polyethethersulfone, filter</td>
			<td>Merck Millipore</td>
			<td>SLHP033RS</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Dimethyl sulfoxide (DMSO)</td>
			<td>Sigma-Aldrich</td>
			<td>D2650</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Collagen coated 96-well plate</td>
			<td>Corning</td>
			<td>NO3585</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Passive Lysis 5xBuffer</td>
			<td>Promega</td>
			<td>E1941</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">GloMax 96 Microplate Luminometer</td>
			<td>Promega</td>
			<td>E6501</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Sucrose</td>
			<td>Nacalai tesque</td>
			<td>30403-55</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Luminometer plate</td>
			<td>Greiner bio-one</td>
			<td>655075</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">HepG2-NTCP1-myc-clone22</td>
			<td>-</td>
			<td>-</td>
			<td>Reference 15</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">pUC1.2HBV delta epsilon</td>
			<td>-</td>
			<td>-</td>
			<td>Reference 15</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">pUC1.2HBV/NL</td>
			<td>-</td>
			<td>-</td>
			<td>Reference 15</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">50 ml tube</td>
			<td>Violamo</td>
			<td>1-3500-02</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Anti-Myc antibody</td>
			<td>Sigma-Aldrich</td>
			<td>C3956</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">HBIG</td>
			<td>Japan Blood Products Organization</td>
			<td>-</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">IFN-&#946;</td>
			<td>Mochida Pharmaceutical</td>
			<td>14987224005413</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Heparin</td>
			<td>Sigma-Aldrich</td>
			<td>H3393</td>
			<td></td>
		</tr>
	</tbody>
</table>

development of a hepatitis b virus reporter system to monitor the early stages of the replication cycle

Currently, it is possible to construct recombinant forms of various viruses, such as human immunodeficiency virus 1 (HIV-1) and hepatitis C virus (HCV), that carry foreign genes such as a reporter or marker protein in their genomes. These recombinant viruses usually faithfully mimic the life cycle of the original virus in infected cells and exhibit the same host range dependence. The development of a recombinant virus enables the efficient screening of inhibitors and the identification of specific host factors. However, to date the construction of recombinant hepatitis B virus (HBV) has been difficult because of various experimental limitations. The main limitation is the compact genome size of HBV, and a fairly strict genome size that does not exceed 1.3 genome sizes, that must be packaged into virions. Thus, the size of a foreign gene to be inserted should be smaller than 0.4 kb if no deletion of the genome DNA is to be performed. Therefore, to overcome this size limitation, the deletion of some HBV DNA is required. Here, we report the construction of recombinant HBV encoding a reporter gene to monitor the early stage of the HBV replication cycle by replacing part of the HBV core-coding region with the reporter gene by deleting part of the HBV pol coding region. Detection of recombinant HBV infection, monitored by the reporter activity, was highly sensitive and less expensive than detection using the currently available conventional methods to evaluate HBV infection. This system will be useful for a number of applications including high-throughput screening for the identification of anti-HBV inhibitors, host factors and virus-susceptible cells.

图1显示了HBV基因组，转录的RNA，病毒蛋白和它们的编码区的基因组的示意图。在基因组中的报告基因和它的位置也被指示。 图2示出了包含报告基因的HBV报告质粒和辅助质粒。所述pUC1.2HBV / NL记者从pUC1.2HBV 16的前C mRNA的转录起始位点删除核苷酸位置223-811，然后插入报告基因构建。通过定点诱变PCR产生与包装信号序列的点突变的pU...

Watch this Scientific Journal Video about Development of a Hepatitis B Virus Reporter System to Monitor the Early Stages of the Replication Cycle at JoVE.com

Development of a Hepatitis B Virus Reporter System to Monitor the Early Stages of the Replication Cycle

这里，我们描述了新开发的乙型肝炎病毒（HBV）报告系统来监视HBV生命周期的早期阶段。 该体外系统的简化将在使用高通量策略抗HBV剂的筛选帮助。

乙型肝炎病毒记者系统的开发监控复制周期的早期阶段

Currently, it is possible to construct recombinant forms of various viruses, such as human immunodeficiency virus 1 (HIV-1) and hepatitis C virus (HCV), ...

development-hepatitis-b-virus-reporter-system-to-monitor-early-stages

Research

JoVE Journal

Immunology and Infection

13.1K 次观看.  National Center for Global Health and Medicine. 这里，我们描述了新开发的乙型肝炎病毒（HBV）报告系统来监视HBV生命周期的早期阶段。 该体外系统的简化将在使用高通量策略抗HBV剂的筛选帮助。 

视频: Development of a Hepatitis B Virus Reporter System to Monitor the Early Stages of the Replication Cycle

Development of a Negative Selectable Marker for Entamoeba histolytica

Entamoeba histolytica is the causative agent of amebiasis and infects up to 10% of the world's population. The molecular techniques that have enabled the up- and down-regulation of gene expression rely on the transfection of stably maintained plasmids. While these have increased our understanding of Entamoeba virulence factors, the capacity to integrate exogenous DNA into genome, which would allow reverse genetics experiments, would be a significant advantage in the study of this parasite. The challenges presented by this organism include inability to select for homologous recombination events and difficulty to cure episomal plasmid DNA from transfected trophozoites. The later results in a high background of exogenous DNA, a major problem in the identification of trophozoites in which a bona fide genomic integration event has occurred. We report the development of a negative selection system based upon transgenic expression of a yeast cytosine deaminase and uracil phosphoribosyl transferase chimera (FCU1) and selection with prodrug 5-fluorocytosine (5-FC). The FCU1 enzyme converts non-toxic 5-FC into toxic 5-fluorouracil and 5-fluorouridine-5'-monophosphate. E. histolytica lines expressing FCU1 were found to be 30 fold more sensitive to the prodrug compared to the control strain.

Development of a Negative Selectable Marker for Entamoeba histolytica

We report development of a negative selection system in E. histolytica based upon transgenic expression of a chimeric protein (FCU1) and selection with the prodrug 5-fluorocytosine. The FCU1 protein is a fusion of yeast cytosine deaminase and uracil phosphoribosyltransferase. Expression of FCU1 resulted in increased E. histolytica sensitivity towards 5-fluorocytosine.

一个负选择标记的发展阿米巴</em

Entamoeba histolytica is the causative agent of amebiasis and infects up to 10% of the world's population. The molecular techniques that have enabled the ...

科研

免疫与感染

Dissecting Host-virus Interaction in Lytic Replication of a Model Herpesvirus

In response to viral infection, a host develops various defensive responses, such as activating innate immune signaling pathways that lead to antiviral cytokine production1,2. In order to colonize the host, viruses are obligate to evade host antiviral responses and manipulate signaling pathways. Unraveling the host-virus interaction will shed light on the development of novel therapeutic strategies against viral infection.
Murine &gamma;HV68 is closely related to human oncogenic Kaposi's sarcoma-associated herpesvirus and Epsten-Barr virus3,4. &gamma;HV68 infection in laboratory mice provides a tractable small animal model to examine the entire course of host responses and viral infection in vivo, which are not available for human herpesviruses. In this protocol, we present a panel of methods for phenotypic characterization and molecular dissection of host signaling components in &gamma;HV68 lytic replication both in vivo and ex vivo. The availability of genetically modified mouse strains permits the interrogation of the roles of host signaling pathways during &gamma;HV68 acute infection in vivo. Additionally, mouse embryonic fibroblasts (MEFs) isolated from these deficient mouse strains can be used to further dissect roles of these molecules during &gamma;HV68 lytic replication ex vivo.
Using virological and molecular biology assays, we can pinpoint the molecular mechanism of host-virus interactions and identify host and viral genes essential for viral lytic replication. Finally, a bacterial artificial chromosome (BAC) system facilitates the introduction of mutations into the viral factor(s) that specifically interrupt the host-virus interaction. Recombinant &gamma;HV68 carrying these mutations can be used to recapitulate the phenotypes of &gamma;HV68 lytic replication in MEFs deficient in key host signaling components. This protocol offers an excellent strategy to interrogate host-pathogen interaction at multiple levels of intervention in vivo and ex vivo.
Recently, we have discovered that &gamma;HV68 usurps an innate immune signaling pathway to promote viral lytic replication5. Specifically, &gamma;HV68 de novo infection activates the immune kinase IKK&beta; and activated IKK&beta; phosphorylates the master viral transcription factor, replication and transactivator (RTA), to promote viral transcriptional activation. In doing so, &gamma;HV68 efficiently couples its transcriptional activation to host innate immune activation, thereby facilitating viral transcription and lytic replication. This study provides an excellent example that can be applied to other viruses to interrogate host-virus interaction.

We describe a protocol to identify key roles of host signaling molecules in lytic replication of a model herpesvirus, gamma herpesvirus 68 (&gamma;HV68). Utilizing genetically modified mouse strains and embryonic fibroblasts for &gamma;HV68 lytic replication, the protocol permits both phenotypic characterization and molecular interrogation of virus-host interactions in viral lytic replication.

解剖宿主 - 病毒相互作用模型疱疹病毒裂解性复制

In response to viral infection, a host develops various defensive responses, such as activating innate immune signaling pathways that lead to antiviral ...

A Protocol for Analyzing Hepatitis C Virus Replication

Hepatitis C Virus (HCV) affects 3% of the world&#8217;s population and causes serious liver ailments including&#160;chronic hepatitis, cirrhosis, and hepatocellular carcinoma. HCV is an enveloped RNA virus belonging to the family Flaviviridae. Current treatment is not fully effective and causes adverse side effects. There is no HCV vaccine available. Thus, continued effort is required for developing a vaccine and better therapy. An HCV cell culture system is critical for studying various stages of HCV growth including viral entry, genome replication, packaging, and egress. In the current procedure presented, we used a wild-type intragenotype 2a chimeric virus, FNX-HCV, and a recombinant FNX-Rluc virus carrying a Renilla luciferase reporter gene to study the virus replication. A human hepatoma cell line (Huh-7 based) was used for transfection of in vitro transcribed HCV genomic RNAs. Cell-free culture supernatants, protein lysates and total RNA were harvested at various time points post-transfection to assess HCV growth. HCV genome replication status was evaluated by quantitative RT-PCR and visualizing the presence of HCV double-stranded RNA. The HCV protein expression was verified by Western blot and immunofluorescence assays using antibodies specific for HCV NS3 and NS5A proteins. HCV RNA transfected cells released infectious particles into culture supernatant and the viral titer was measured. Luciferase assays were utilized to assess the replication level and infectivity of reporter HCV. In conclusion, we present various virological assays for characterizing different stages of the HCV replication cycle.

Hepatitis C Virus (HCV) is a major human pathogen that causes liver disorders, including cirrhosis and cancer. An HCV infectious cell culture system is essential for understanding the molecular mechanism of HCV replication and developing new therapeutic approaches. Here we describe a protocol to investigate various stages of the HCV replication cycle.

一个协议，用于分析丙型肝炎病毒复制

Hepatitis C Virus (HCV) affects 3% of the world&#8217;s population and causes serious liver ailments including&#160;chronic hepatitis, cirrhosis, and ...

Mouse Fetal Liver Culture System to Dissect Target Gene Functions at the Early and Late Stages of Terminal Erythropoiesis

Erythropoiesis involves a dynamic process that begins with committed erythroid burst forming units (BFU-Es) followed by rapidly dividing erythroid colony forming units (CFU-Es). After CFU-Es, cells are morphologically recognizable and generally termed terminal erythroblasts. One of the challenges for the study of terminal erythropoiesis is the lack of experimental approaches to dissect gene functions in a chronological manner. In this protocol, we describe a unique strategy to determine gene functions in the early and late stages of terminal erythropoiesis. In this system, mouse fetal liver TER119 (mature erythroid cell marker) negative erythroblasts were purified and transduced with exogenous expression of cDNAs or small hairpin RNAs (shRNAs) for the genes of interest. The cells were subsequently cultured in medium containing growth factors other than erythropoietin (Epo) to maintain their progenitor stage for 12 hr while allowing the exogenous cDNAs or shRNAs to express. The cells were changed to Epo medium after 12 hr to induce cell differentiation and proliferation while the exogenous genetic materials were already expressed. This protocol facilitates analysis of gene functions in the early stage of terminal erythropoiesis. To study late stage terminal erythropoiesis, cells were immediately cultured in Epo medium after transduction. In this way, the cells were already differentiated to the late stage of terminal erythropoiesis when the transduced genetic materials were expressed. We recommend a general application of this strategy that would help understand detailed gene functions in different stages of terminal erythropoiesis.

We present an in vitro mouse fetal liver erythroblast culture system that dissects the early and late stages of terminal erythropoiesis. This system facilitates functional analysis of specific genes in different developmental stages.

小鼠胎肝文化系统解剖靶基因功能的终端红细胞生成的早期和晚期

Erythropoiesis involves a dynamic process that begins with committed erythroid burst forming units (BFU-Es) followed by rapidly dividing erythroid colony ...

In Vitro Analysis of Myd88-mediated Cellular Immune Response to West Nile Virus Mutant Strain Infection

An attenuated West Nile virus (WNV), a nonstructural (NS) 4B-P38G mutant, induced higher innate cytokine and T cell responses than the wild-type WNV in mice. Recently, myeloid differentiation factor 88 (MyD88) signaling was shown to be important for initial T cell priming and memory T cell development during WNV NS4B-P38G mutant infection. In this study, two flow cytometry-based methods &#8211; an in vitro T cell priming assay and an intracellular cytokine staining (ICS) &#8211; were utilized to assess dendritic cells (DCs) and T cell functions. In the T cell priming assay, cell proliferation was analyzed by flow cytometry following co-culture of DCs from both groups of mice with carboxyfluorescein succinimidyl ester (CFSE) - labeled CD4+ T cells of OTII transgenic mice. This approach provided an accurate determination of the percentage of proliferating CD4+ T cells with significantly improved overall sensitivity than the traditional assays with radioactive reagents. A microcentrifuge tube system was used in both cell culture and cytokine staining procedures of the ICS protocol. Compared to the traditional tissue culture plate-based system, this modified procedure was easier to perform at biosafety level (BL) 3 facilities. Moreover, WNV- infected cells were treated with paraformaldehyde in both assays, which enabled further analysis outside BL3 facilities. Overall, these in vitro immunological assays can be used to efficiently assess cell-mediated immune responses during WNV infection.

In Vitro Analysis of Myd88-mediated Cellular Immune Response to West Nile Virus Mutant Strain Infection

Two flow cytometry-based methods &#8211; an in vitro T cell priming assay and intracellular cytokine staining were utilized to measure antigen presenting capacity of dendritic cells and antigen-specific T cell responses to a West Nile virus mutant infection in mice.

在 MyD88的介导的细胞免疫应答西尼罗河病毒变异株感染体外分析

An attenuated West Nile virus (WNV), a nonstructural (NS) 4B-P38G mutant, induced higher innate cytokine and T cell responses than the wild-type WNV in ...

Immunofluorescence to Monitor the Cellular Uptake of Human Lactoferrin and its Associated Antiviral Activity Against the Hepatitis C Virus

Immunofluorescence is a laboratory technique commonly used to study many aspects of biology. It is typically used to visualize the distribution and/or localization of a target molecule in cells and tissues. Immunofluorescence relies on the specificity of fluorescent-labelled antibodies against their corresponding antigens within a cell. Both direct and indirect immunofluorescence approaches can be used which rely on the use of antibodies linked with a fluorochrome. Direct immunofluorescence is less frequently used because it provides lower signal, involves higher cost and less flexibility. In contrast, indirect immunofluorescence is more commonly used because of its high sensitivity and provides an amplified signal since more than one secondary antibody can attach to each primary antibody. In this manuscript, both epifluorescence microscopy and confocal microscopy were used to monitor the internalization of human lactoferrin, an important component of the immune system, into hepatic cells. Moreover, we monitored the inhibitory potential of hLF on the intracellular replication of the Hepatitis C virus using immunofluorescence. Both the advantages and disadvantages associated with these approaches are discussed.

The human lactoferrin (hLF) is a component of the immune system. In this study, immunofluorescence assays are used to demonstrate both the hepatocellular uptake of hLF and a qualitative reduction in the hepatitis C virus replication upon treatment with hLF.

免疫监视人乳铁蛋白的细胞摄取及其相关抗病毒活性抗丙型肝炎病毒

Immunofluorescence is a laboratory technique commonly used to study many aspects of biology. It is typically used to visualize the distribution and/or ...

Rearing Ixodes scapularis, the Black-legged Tick: Feeding Immature Stages on Mice

Ixodes scapularis, the vector of Lyme disease, is one of the most important disease vectors in the eastern and Midwestern United States. This species is a three host tick that requires a blood meal from a vertebrate host for each development stage, and the adult females require a blood meal for reproduction. Larval ticks attach to their host for 3 - 5 days for feeding and drop off the host when fully engorged. This dependency on several different hosts and the lengthy attachment time for engorgement complicates tick rearing in the laboratory setting. However, to understand tick biology and tick-pathogen interactions, the production of healthy, laboratory-reared ticks is essential. Here, we demonstrate a simple, cost-effective protocol for immature tick feeding on mice. We modified the existing protocols for decreased stress on mice and increased tick feeding success and survival by using disposable cages without mesh bottoms to avoid contact of ticks with water contaminated with mice urine and feces.

Rearing Ixodes scapularis, the Black-legged Tick: Feeding Immature Stages on Mice

The production of healthy laboratory-reared ticks is essential to studies on tick biology, and tick-pathogen interactions. Here we demonstrate a simple protocol for immature tick feeding that is cost-effective and less stressful to mice.

饲养<em&gt;肩突硬蜱，</em&gt;黑腿蜱:饲养对小鼠未成熟阶段

Ixodes scapularis, the vector of Lyme disease, is one of the most important disease vectors in the eastern and Midwestern United States. This species is a ...

A Novel Feeder-free System for Mass Production of Murine Natural Killer Cells In Vitro

Natural killer (NK) cells belong to the innate immune system and are a first-line anti-cancer immune defense; however, they are suppressed in the tumor microenvironment and the underlying mechanism is still largely unknown. The lack of a consistent and reliable source of NK cells limits the research progress of NK cell immunity. Here, we report an in vitro system that can provide high quality and quantity of bone marrow-derived murine NK cells under a feeder-free condition. More importantly, we also demonstrate that siRNA-mediated gene silencing successfully inhibits the E4bp4-dependent NK cell maturation by using this system. Thus, this novel in vitro NK cell differentiating system is a biomaterial solution for immunity research.

A Novel Feeder-free System for Mass Production of Murine Natural Killer Cells In Vitro

Here, we present a protocol to mass-produce gene-silencing murine NK cells by using a feeder-free differentiation system for mechanistic study in vitro and in vivo.

一种新型大鼠自然杀伤细胞无饲养系统的研究体外

Natural killer (NK) cells belong to the innate immune system and are a first-line anti-cancer immune defense; however, they are suppressed in the tumor ...

Assembly and Purification of Prototype Foamy Virus Intasomes

A defining feature and necessary step of the retrovirus life cycle is the integration of the viral genome into the host genome. All retroviruses encode an integrase (IN) enzyme that catalyzes the covalent joining of viral to host DNA, which is known as strand transfer. Integration may be modeled in vitro with recombinant retroviral IN and DNA oligomers mimicking the ends of the viral genome. In order to more closely recapitulate the integration reaction that occurs in vivo, integration complexes are assembled from recombinant IN and synthetic oligomers by dialysis in a reduced salt concentration buffer. The integration complex, called an intasome, may be purified by size exclusion chromatography. In the case of prototype foamy virus (PFV), the intasome is a tetramer of IN and two DNA oligomers and is readily separated from monomeric IN and free oligomer DNA. The integration efficiency of PFV intasomes may be assayed under a variety of experimental conditions to better understand the dynamics and mechanics of retroviral integration.

Recombinant retroviral integrase and DNA oligomers mimicking viral DNA ends can form an enzymatically active complex known as an intasome. Intasomes may be used for biochemical, structural, and kinetic studies. This protocol details how to assemble and purify prototype foamy virus intasomes.

泡沫病毒 Intasomes 原型的组装与纯化

A defining feature and necessary step of the retrovirus life cycle is the integration of the viral genome into the host genome. All retroviruses encode an ...

Rapid, Safe, and Simple Manual Bedside Nucleic Acid Extraction for the Detection of Virus in Whole Blood Samples

The rapid diagnosis of an infection is essential for the outbreak management, risk containment, and patient care. We have previously shown a method for the rapid bedside inactivation of the Ebola virus during blood sampling for safe nucleic acid (NA) tests by adding a commercial lysis/binding buffer directly into the vacuum blood collection tubes. Using this bedside inactivation approach, we have developed a safe, rapid, and simplified bedside NA extraction method for the subsequent detection of a virus in lysis/binding buffer-inactivated whole blood. The NA extraction is directly performed in the blood collection tubes and requires no equipment or electricity. 
After the blood is collected into the lysis/binding buffer, the contents are mixed by flipping the tube by hand, and the mixture is incubated for 20 min at room temperature. Magnetic glass particles (MGPs) are added to the tube, and the contents are mixed by flipping the collection tube by hand. The MGPs are then collected on the side of the blood collection tube using a magnetic holder or a magnet and a rubber band. The MGPs are washed three times, and after the addition of elution buffer directly into the collection tube, the NAs are ready for NA tests, such as qPCR or isothermal loop amplification (LAMP), without the removal of the MGPs from the reaction. The NA extraction method is not dependent on any laboratory facilities and can easily be used anywhere (e.g., in field hospitals and hospital isolation wards). When this NA extraction method is combined with LAMP and a portable instrument, a diagnosis can be obtained within 40 min of the blood collection.

Here, we present a protocol for the rapid virus nucleic acid extraction from the virus-inactivated whole blood. The extraction is performed directly in the blood collection tubes and requires no equipment or electricity. The method is not dependent on laboratory facilities and can be used anywhere (e.g., in field hospitals).

快速、安全、简便的人工床边核酸提取法检测全血标本中的病毒

The rapid diagnosis of an infection is essential for the outbreak management, risk containment, and patient care. We have previously shown a method for ...