慢病毒载体介导的肝细胞基因转移

慢病毒(lentivirus)具有可以感染低分裂细胞的独特优势,且基因转移效率高,操作相对简便,在多种疾病的基因治疗、转基因动物的制备等方面成为引人瞩目的病毒载体。本文就慢病毒载体(lentiviral vector,LV)的特点、构建、应用,尤其是慢病毒载体对于肝细胞的基因转移进行综述。     

慢病毒载体介导的肝细胞基因转移

慢病毒（lentivirus）具有可以感染低分裂细胞的独特优势,且基因转移效率高,操作相对简便,在多种疾病的基因治疗、转基因动物的制备等方面成为引人瞩目的病毒载体。本文就慢病毒载体（lentiviral vector,LV）的特点、构建、应用,尤其是慢病毒载体对于肝细胞的基因转移进行综述。     

成年大鼠胰岛的体外基因转染

目的 探讨携带外源基因的慢病毒在体外有效感染胰岛及外源基因在胰岛中的表达，为通过移植前向胰岛细胞转入特定的免疫调节分子基因诱导胰岛移植物耐受奠定基础。方法 将目的基因CTLA4Ig导入慢病毒载体pWPTS，构建成pWPTS-CTLA4Ig载体。用磷酸钙沉淀法将pWPTS-EGFP、pWPTS-CTLA4Ig分别和其辅助载体pMD2．G、pCMVΔ8．92共转染293T细胞，收获病毒上清液，测定病毒滴度后感染新分离的胰岛。通过Western Blot测定胰岛培养上清液中CTLA4Ig蛋白的表达。结果 ①成功构建了携带CTLA4Ig基因的慢病毒载体pWPTS-CTLA4Ig；②包装产生的慢病毒Lenti-EGFP、Lenti-CTLA4Ig在体外可以感染胰岛，其中在Lenti-EGFP慢病毒感染的胰岛观察到了绿色荧光，及在Lenti-CTLA4Ig慢病毒感染的胰岛培养上清液中检测到了CTLA4Ig蛋白的表达。结论 慢病毒在体外可以有效感染大鼠胰岛，且携带的外源基因可以在胰岛细胞中稳定表达，其中Lenti-CTLA4Ig慢病毒感染的胰岛为进行胰岛移植并诱导体内特异的胰岛移植物耐受奠定了基础。     

HIV-Ⅰ慢病毒载体的研究进展与应用

基因治疗是治疗肿瘤、遗传病等难治性疾病的最有效手段之一,但目前的基因转移方法存在一定的局限性,成为基因治疗和广泛应用的障碍.以1型人类免疫缺陷病毒(HIV-1)为基础构建的慢病毒载体(LV)具有感染分裂及非分裂细胞、使目的 基因产物表达稳定、表达时间长、载体自身免疫原性小等优点,尤其是LV能有效诱导免疫应答,抑制肿瘤生长,诱导移植免疫耐受等,是很有发展潜力的体内基因治疗新载体.     

人神经生长因子β亚基慢病毒载体的构建

背景：糖尿病神经源性膀胱的发病与神经生长因子缺乏有关,β亚基是构成神经生长因子(NGF)3种亚基中惟一具有生物活性的亚基,慢病毒载体是基因治疗的理想载体。 目的：构建过表达人神经生长因子β亚基(β-NGF)基因的慢病毒载体。 方法：通过目的基因的获得,载体质粒双酶切,载体质粒与目的基因的连接将人β-NGF基因克隆到慢病毒载体质粒pGC-FU中,构建重组慢病毒载体质粒pGC-FU-β-NGF。观察人β-NGF基因的克隆情况,并进行重组慢病毒载体质粒pGC-FU-β-NGF的PCR鉴定和测序。 结果与结论：构建的重组慢病毒载体质粒pGC-FU-β-NGF进行PCR实际获得的产物与预计PCR产物大小一致,即初步判断为构建成功的重组质粒。所获得的β-NGF基因经测序后与GenBank报道序列完全一致。说明pGC-FU-β-NGF中携带有正确的β-NGF基因。结果证实,实验成功构建了携带人β-NGF基因的重组慢病毒载体质粒。     

慢病毒载体与基因治疗

载体是供插入目的基因并将其导入宿主细胞内表达或复制的运载工具。常用的有SV40衍生载体、逆转录病毒载体、腺病毒载体、腺病毒相关病毒载体、细小病毒载体、疱疹病毒载体、痘苗病毒载体等。近几年来。慢病毒载体受到高度重视，慢病毒载体来源于人类免疫缺陷病毒HIV-1、HIV-2、SIV，具有转染分裂和非分裂的T细胞、树枝状细胞、造血干细胞及巨噬细胞^[1]，基因疗法是一种新方法。Hawley^[2]等的文章中指出。由于慢病毒载体可作用于细胞周期的G0／G1期。成为遗传性疾病治疗的有效手段。基因治疗的最初目的是传送特殊的基因至预定的靶细胞，并且直接表达该基因的性质，达到治疗效果。在治疗遗传性、代谢性、神经系统疾病、癌症及艾滋病方面有广泛的应用前景。     

感染靶向性重组腺相关病毒载体在基因治疗中的研究进展

重组腺相关病毒（rAAV）是一种非常有希望的人体细胞基因治疗载体.它既可以转染分裂细胞又可以转染非分裂细胞.rAAV在宿主体内以定向整合的方式存在.AAV重组体在细胞内能长期稳定地表达,且在体内不引起明显的病理变化,然而它广泛的宿主范围是体内基因治疗的一个缺点,因为它不具备组织特异性或器官局限性转导能力从而难以增加其在基因治疗中的安全性和效率.因此,开发具有组织或器官靶向性的重组腺相关载体是腺相关病毒载体发展的方向.本文就近年来感染靶向性腺相关病毒在基因治疗中的进展作一综述.     

大鼠微小RNA miR-16的克隆及其慢病毒表达载体的构建

目的 克隆微小RNA rno-miR-16,构建其慢病毒表达载体pLV-miR-16并包装成慢病毒颗粒,为进一步研究miR-16的功能奠定了实验基础.方法 从大鼠细胞基因组中用PCR 的方法扩增miR-16 的前体,构建了miR-16的重组表达载体pLV-miR-16,脂质体法将重组慢病毒载体和包装质粒混合物(pPACK-GAG、pPACK-REV和pVSV)共转染包装细胞293TN细胞,包装产生慢病毒,以293TN细胞绿色荧光蛋白(green fluorescent protein,GFP)的表达水平测定病毒滴度.结果 经PCR扩增检测阳性菌落和测序证实,成功构建携带大鼠miR-16基因重组慢病毒载体.倒置荧光显微镜下观察可见包装细胞293TN呈绿色荧光,并测得108＞ifu/ml.结论 成功构建大鼠慢病毒载体pLV-miR-16,为深入研究rno-miR-16的生物学功能奠定了基础.     

mTOR shRNA慢病毒载体的构建及包装

目的:构建mTORshRNA慢病毒表达载体,为探讨RNA干扰技术抑制T细胞mTOR基因的相关研究奠定基础.方法:设计合成针对小鼠mTOR基因的shRNA片段,与酶切后的pLKD.UBC.GFP.U6载体片段进行连接并转化DH5α,提取阳性克隆质粒,测序,转染293T细胞.通过GFP表达水平测定病毒滴度.结果:DNA测序结果及PCR鉴定证实成功构建小鼠mTOR-shRNA重组慢病毒载体,对其进行包装后测定慢病毒滴度为1.38E+ 08 TU/ml.结论:成功构建并包装小鼠mTOR-shRNA重组慢病毒表达载体.     

感染靶向性重组腺相关病毒载体在基因治疗中的研究进展

重组腺相关病毒(rAAV)是一种非常有希望的人体细胞基因治疗载体.它既可以转染分裂细胞又可以转染非分裂细胞.rAAV在宿主体内以定向整合的方式存在.AAV重组体在细胞内能长期稳定地表达,且在体内不引起明显的病理变化,然而它广泛的宿主范围是体内基因治疗的一个缺点,因为它不具备组织特异性或器官局限性转导能力从而难以增加其在基因治疗中的安全性和效率.因此,开发具有组织或器官靶向性的重组腺相关载体是腺相关病毒载体发展的方向.本文就近年来感染靶向性腺相关病毒在基因治疗中的进展作一综述.     

Anticancer activity of NOB1-targeted shRNA combination with TRAIL in epithelial ovarian cancer cells

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) based strategy is a promising targeted therapeutic approach for the treatment of ovarian cancer. However, the effectiveness of the treatment remains limited due to the inherent or acquired resistance of tumor cells to TRAIL. Our previously study demonstrated that downregulation of NOB1 (NIN1/RPN12 binding protein 1 homolog) expression by a lentiviral short hairpin RNA (shRNA) delivery system (Lv/sh-NOB1) suppressed ovarian cancer growth. Here, Lv/sh-NOB1 and TRAIL were combined and tested the effects of this combination on ovarian cancer cells to identify more effective therapeutics against ovarian cancer by several in vitro experiments. Tumor growth ability in SKVO3 xenograft nude mice was also determined to define this combination treatment effect in tumorigenesis in vivo. In vitro assay showed that Lv/sh-NOB1 in combination with TRAIL treatment in ovarian cancer cell synergistically suppressed the proliferation and colony formation, as well as induced cell apoptosis and increased the activity of caspase-3, -8 and -9. In vivo assay showed that Lv/sh-NOB1 combination with TRAIL synergistically suppressed tumor growth of nude mice model. Importantly, we found that downregulation of NOB1 could upregulate DR5 expression and active MAPK pathway, which might contribute to increase sensitivity TRAIL to ovarian cancer cells. These findings suggested that Lv/sh-NOB1 combination with TRAIL treatment may be a potential treatment approach for ovarian cancer.     

Heavy chain (LvH) and light chain (LvL) of lipovitellin (Lv) of zebrafish can both bind to bacteria and enhance phagocytosis

Lipovitellin (Lv) is an apoprotein in oviparous animals. Lv consists of a heavy chain (LvH) and a light chain (LvL) which are traditionally regarded as energy reserves for developing embryos. Recently, Lv has been shown to be involved in immune defense of developing embryos in fish. However, it remains unknown if each of LvH and LvL possesses immune activity; and if so, whether or not they function similarly. Here we clearly demonstrated that recombinant LvH (rLvH) and LvL (rLvL) from zebrafish vg1 gene bound to both the Gram-negative bacteria Escherichia coli and Vibrio anguillarum and the Gram-positive bacteria Staphylococcus aureus and Micrococcus luteus as well as the pathogen-associated molecular patterns LPS, LTA and PGN. In addition, both rLvH and rLvL were able to enhance the phagocytosis of bacteria E. coli and S. aureus by macrophages. All these data suggest that both LvH and LvL, in addition to being energy reserves, are also maternal immune-relevant factors capable of interacting with invading bacteria in zebrafish embryos/larvae.     

Comparative and mutational analyses of promoter regions of rinderpest virus

Comparative and mutational analysis of promoter regions of rinderpest virus was conducted. Minigenomic RNAs harboring the genomic and antigenomic promoter of the lapinized virulent strain (Lv) or an attenuated vaccine strain (RBOK) were constructed, and the expression of the reporter gene was examined. The activities of the antigenomic promoters of these strains were similar, whereas the activity of the genomic promoter (GP) of the RBOK strain was significantly higher than that of the Lv strain, regardless of cell type and the source of the N, P and L proteins. Increased replication (and/or encapsidation) activities were observed in the minigenomes that contained RBOK GP. Mutational analysis revealed that the nucleotides specific to the RBOK strain are responsible for the strong GP activity of the strain. It was also demonstrated that other virulent strains of RPV (Kabete O, Saudi/81 and Kuwait 82/1) have weaker GPs than that of the RBOK strain.     

Role of HIV-2 envelope in Lv2-mediated restriction

We have characterized envelope protein pseudotyped HIV-2 particles derived from two HIV-2 isolates termed prCBL23 and CBL23 in order to define the role of the envelope protein for the Lv2-mediated restriction to infection. Previously, it has been described that the primary isolate prCBL23 is restricted to infection of several human cell types, whereas the T cell line adapted isolate CBL23 is not restricted in these cell types. Molecular cloning of the two isolates revealed that the env and the gag gene are responsible for the observed phenotype and that this restriction is mediated by Lv2, which is distinct from Ref1/Lv1 (Schmitz, C., Marchant, D., Neil, S.J., Aubin, K., Reuter, S., Dittmar, M.T., McKnight, A., Kizhatil, K., Albritton, L.M., 2004. Lv2, a novel postentry restriction, is mediated by both capsid and envelope. J. Virol. 78 (4), 2006-2016). We generated pseudotyped viruses consisting of HIV-2 (ROD-ADeltaenv-GFP, ROD-ADeltaenv-RFP, or ROD-ADeltaenv-REN) and the prCBL23 or CBL23 envelope proteins as well as chimeric proteins between these envelopes. We demonstrate that a single amino acid exchange at position 74 in the surface unit of CBL23-Env confers restriction to infection. This single point mutation causes tighter CD4 binding, resulting in a less efficient fusion into the cytosol of the restricted cell line. Prevention of endosome formation and prevention of endosome acidification enhance infectivity of the restricted particles for GHOST/X4 cells indicating a degradative lysosomal pathway as a cause for the reduced cytosolic entry. The described restriction to infection of the primary isolate prCBL23 is therefore largely caused by an entry defect. A remaining restriction to infection (19-fold) is preserved when endosomal acidification is prevented. This restriction to infection is also dependent on the presence of the point mutation at position 74 (G74E).     

灭活柯萨奇B1病毒在原代培养骨骼肌细胞中促进基因转移 …

研究灭活后的柯萨奇病毒在原代培养骨骼肌细胞中，对报道基因ｐＣＤＮＡ３－ＬａｃＺ转移效率的影响。方法用聚乙二醇沉淀和蔗糖低温超速离心法提纯并用β－丙内酯灭活病毒，将灭活ＣＶＢ１，转铁蛋白聚赖氨和报道基因设计成不同浓度组合，观察肌肉细胞中β－乳糖苷酶染色阳性的细胞数。     

Inhibition of Taura syndrome virus replication in <Emphasis Type="Italic">Litopenaeus vannamei</Emphasis> through silencing the LvRab7 gene using double-stranded RNA

Taura syndrome virus (TSV) is a major cause of high mortality in Pacific white shrimp (Litopenaeus vannamei, Lv). Previously, silencing of Penaeus monodon Rab7 (PmRab7) by injecting double-stranded RNA corresponding to PmRab7 (dsRNA-PmRab7) prevented white spot syndrome virus or yellow head virus infection. Rab7 is proposed to be involved in intracellular trafficking of the viruses. This study aimed to investigate whether knockdown of Rab7 in L. vannamei by dsRNA-PmRab7 could inhibit replication of TSV. RNA interference (RNAi) technology using dsRNA targeting the LvRab7 gene was used to silence the mRNA expression of LvRab7. The silencing of the LvRab7 gene inhibited TSV replication dramatically when compared to groups receiving dsRNA-GFP or NaCl. This is the first demonstration that dsRNA targeting the endogenous shrimp gene LvRab7 strongly reduces TSV replication. It provides further evidence that LvRab7 is involved in the endosomal trafficking pathway of viruses infecting penaeid shrimp.     

A defective HIV-1 vector for gene transfer to human lymphocytes

Conclusions All practical development of HIV-1 vectors for in vivo testing will require high titers of recombinant virus free of helper virus. To date, an HIV-based vector system with an efficiency of gene transfer comparable to that achieved by the Mo-MuLV-based system has not yet been developed. Such development will require a better definition of the optimal placement of viral cis-acting sequences within the HIV-1 vector. The establishment of stable packaging cell lines should increase the efficiency of production of recombinant HIV-1 viruses for future use. T-lymphocytes are, in fact, an important potential target for therapeutic gene transfer. The possible advantages of such vectors over currently available retroviral vectors suggest that the continued study of HIV-1 vectors for gene transfer to human T-lymphocytes is warranted.Abbreviations HIV Human immunodeficiency virus - LTR Long terminal repeat     

脊髓血供的计量学观察

目的 :探讨脊髓内部血管构筑和分布 ,为脊髓缺血性的有关病变、治疗和预后提供形态学基础。方法 :应用碱性磷酸酶血管染色法 ,对脊髓内部血管 ,用体视学方法作计量和观察。结果 :在脊髓内部灰、白质的毛细血管体密度 ,表面积密度、长度密度存在着差异。结论 :灰质内毛细血管的体密度 ,表面积密度、长度密度均明显高于白质 ,灰质前角的毛细血管量明显多于后角 ,而白质毛细血管的体密度是 :前索 >侧索 >后索