水泡性口炎病毒印第安纳株反基因操作系统的建立

负链RNA病毒作为活病毒载体具有巨大的优势。本研究构建了水泡性口炎病毒印第安纳株（VSV-Ind）基因组全长cDNA克隆，建立了反向遗传操作系统并成功救获病毒。通过免疫荧光、电镜观察、RT-PCR及生长动力学研究，证实救获病毒保持典型的VSV印第安纳株特点，救获VSV的基因组内G蛋白前、后非编码区分别引入两个用于进一步构建重组病毒时外源基因插入的两个限制酶位点。本研究为新型重组活病毒疫苗载体和肿瘤治疗载体的研制及基础病毒学相关研究提供了重要的技术平台。     

表达水疱性口炎病毒G基因重组新城疫病毒的构建及免疫原性研究

水疱性口炎是由水疱性口炎病毒(VSV)引起的人兽共患性传染病,在我国尚无可用疫苗。为研制安全有效的水疱性口炎疫苗,本研究以新城疫病毒(NDV)LaSota弱毒疫苗株反向遗传操作系统为基础,构建并拯救出表达VSV糖蛋白(GP)的重组病毒(rLa-VSV-G)。间接免疫荧光、激光共聚焦、western blot等试验证明VSV-GP在重组病毒中正确表达;体外致病试验结果表明,rLa-VSV-G保持了LaSota亲本株的低致病性和高滴度的鸡胚生长特性;rLa-VSV-G接种4周龄~5周龄BALB/c雌性小鼠后,可以诱导显著的VSV中和抗体反应。本研究表明,重组病毒rLa-VSV-G具有作为防控VSV储备性疫苗的潜力。     

表达鸡传染性支气管炎病毒S基因的重组新城疫病毒构建

为构建以新城疫病毒(NDV)为活毒载体表达鸡传染性支气管炎病毒(IBV)S基因的重组病毒,本研究利用RT-PCR技术,以IBV的Massachusetts41株RNA为模板,通过RT-PCR扩增得到IBV S基因(3534bp),将其插入到NDV感染性克隆pBRN-FL中,构建了含有IBV S基因的重组NDV cDNA克隆pBRN-FL-IBVS。利用磷酸钙转染法,在辅助质粒pBS-NP、pBS-P和pBS-L的共同作用下,将pBRN-FL-IBVS转染表达T7聚合酶重组痘病毒感染的BSR细胞,救获重组NDV(rL-IBVS)。采用RT-PCR检测接种重组病毒的鸡胚尿囊液,结果表明rL-IBVS中含有相应外源基因。IFA试验表明,rL-IBVS可与鸡抗IBV的高免血清发生特异性反应,证明S蛋白在感染的BSR细胞中得到表达。其鸡胚平均致死时间、脑内致病指数和静脉内致病指数等指标显示rL-IBVS保持了亲本疫苗株高滴度的鸡胚生长特性和低致病力特性。本研究采用反向遗传操作技术构建了表达IBV S蛋白的重组NDV,为进一步研制IBV和NDV的重组基因工程活载体疫苗奠定了基础。     

埃博拉和马尔堡病毒囊膜糖蛋白嵌合型重组水泡性口炎病毒的构建及鉴定

埃博拉病毒(EBOV)和马尔堡病毒(MARV)属于丝状病毒科,能够导致人和动物发生致命的埃博拉出血热和马尔堡出血热,这两种病是重要的尚未传入我国的烈性人兽共患病。为研制安全有效的储备疫苗,本研究利用水泡性口炎病毒(VSV)反向遗传操作技术,将VSV自身糖蛋白(GP)分别替换为EBOV或MARV的GP,构建了表达扎伊尔型EBOV、苏丹型EBOV及MARV GP的嵌合VSV重组病毒r VSV△G/ZEBOVGP、r VSV△G/SEBOVGP及r VSV△G/MARVGP。Western blot和间接免疫荧光试验表明这3种GP蛋白在重组病毒感染的细胞中均能够正确表达。电镜观察结果显示,3种重组病毒均与亲本病毒具有相同形态特征,表明这3种外源GP蛋白均能够嵌合在重组病毒粒子表面。本研究构建的这3种重组病毒为进一步的动物免疫试验并评价其免疫效果奠定了基础。     

水泡性口炎病毒N蛋白的原核表达和鉴定

根据GenBank已公布的水泡性口炎病毒(Vesicular stomatitis virus,VSV)N基因序列,设计上、下游引物,以VSV-NJ核酸为模板进行RT-PCR扩增,扩增产物克隆至pET52 3C/LIC载体中,成功构建了pET52-VSV N表达载体。将pET52-VSV N重组质粒转化大肠杆菌BL21(DE3)进行融合表达,经SDS-PAGE电泳分析,可见VSV N蛋白成功得到了表达,融合蛋白的分子量约为50KD,Western blot分析表明所表达的重组蛋白可与VSV阳性羊血清发生特异性反应,表达的VSV N蛋白可以作为建立VSV抗体检测方法的抗原。     

水泡性口炎病毒M基因的克隆表达及多克隆抗体的制备

为制备水泡性口炎病毒(vesicular stomatitis virus,VSV)重组M蛋白的鼠源多克隆抗体,本研究将扩增的VSV-M基因插入到pET-28a载体中,构建了pET-28a-VSV-M原核表达载体,将其转化至大肠杆菌表达菌株E.coli BL21(DE3)后,用IPTG进行诱导表达;SDS-PAGE和Western blot检测结果发现重组蛋白主要以包涵体形式存在,相对分子质量约为31 000。之后应用His GraviTrap 10prepacked gravity flow columns纯化重组M蛋白,并将其免疫小鼠,制备VSV重组M蛋白的多克隆抗体;间接ELISA方法检测其抗体效价为1∶12 800。将该抗体应用于VSV的检测,在稀释倍数为1∶800时仍可检测到清晰的条带,且大小与预期的一致,证实了其与病毒的特异性结合。结果表明,本研究成功构建了VSV-M蛋白的原核表达载体,将表达纯化后的VSV-M蛋白免疫小鼠成功制备了VSV-M蛋白的多克隆抗体,这为后期检测VSV-M基因的表达分布、功能特性及开发诊断试剂和疫苗的研制奠定了基础。     

表达水泡性口炎病毒双血清型G蛋白重组腺病毒的构建及对小鼠的免疫原性分析

旨在以人5型复制缺陷型腺病毒为表达载体,构建表达水泡性口炎病毒(VSV)双血清型G蛋白的重组腺病毒。利用融合PCR技术扩增VSV-IN-G-NJ-G基因并将其克隆至腺病毒穿梭载体pacAd-CMV K-NpA中。通过PacⅠ酶线性化后,与同样经PacⅠ酶线性化的骨架载体pacAd5 9.2-100共转染AAV-293细胞,获得重组腺病毒rAd-VSV-IN-G-NJ-G。该重组腺病毒于AAV-293细胞连续传代至20代效价稳定。经间接免疫荧光和Western blot检测,G蛋白获得正确表达。将重组腺病毒接种小鼠,利用间接ELISA及病毒中和试验检测其体液免疫水平,结果显示可诱导产生VSV特异性抗体,其中和抗体水平在1∶32;利用淋巴细胞增殖试验检测细胞免疫水平,结果表明可以引起接种小鼠强烈的淋巴细胞增殖。构建的重组腺病毒免疫小鼠后可以引起一定的体液免疫和细胞免疫反应,为表达VSV糖蛋白重组腺病毒疫苗的深入研究奠定了基础。     

表达扎伊尔型埃博拉病毒囊膜糖蛋白重组水泡性口炎病毒的构建

埃博拉病毒(EBOV)能够引起一种人畜共患急性出血性传染病,即埃博拉出血热.研制安全、有效的抗病毒疫苗具有重要意义.本研究利用水泡性口炎病毒(VSV)印第安纳株反向遗传操作系统,构建并拯救得到表达扎伊尔型埃博拉病毒(ZEBOV)囊膜糖蛋白GP的重组VSV (rVSV-ZEBOV-GP),通过westemblot和免疫荧光试验证明在重组病毒中ZEBOV GP蛋白获得正确表达;动物试验显示重组病毒对小鼠高度安全;中和试验结果表明重组病毒能诱导小鼠产生针对ZEBOV囊膜糖蛋白GP嵌合VSV假病毒粒的特异性中和抗体.本研究表明rVSV-ZEBOV-GP作为防控ZEBOV的储备性疫苗具有潜在的应用价值.     

Matrix蛋白和G蛋白双位点突变型水泡性口炎病毒的构建及生物学活性观察

重组水泡性口炎病毒(Vesiclar stomatitis virs,VSV)是一种具有良好应用前景的病毒载体,可应用于制备疫苗和治疗肿瘤,但该载体仍存在安全性问题,高剂量注射实验动物可导致产生神经毒性.为减低乃至去除野生型VSV的致病性,作者针对VSV毒力因子,构建了Matrix蛋白和G蛋白双位点突变型重组VSV,该病毒敲除了原来Matrix蛋白的第51位精氨酸和G蛋白C末端的28个氨基酸.相比野生型VSV,新病毒的致病性显著降低.试验也证实这个致弱的病毒是由于2种不同弱化机理共同作用所致,即Ⅰ型干扰素作用和复制能力减低.新型VSV病毒载体有希望成为一个更安全、有效的疫苗载体.     

表达犬瘟热病毒H基因重组新城疫病毒的构建及其免疫原性研究

为研制安全、有效的新型犬瘟热疫苗,本研究利用新城疫病毒(NDV) LaSota弱毒疫苗株反向遗传操作系统,构建出表达犬瘟热病毒(CDV)弱毒疫苗株Rockborn-20/8血凝素(H)蛋白的重组病毒rLa-CDV-H,并对其生物学特性进行鉴定,评估其作为犬瘟热活载体疫苗的安全性和有效性.通过免疫荧光和western blot试验证明了CDV H蛋白的正确表达;重组病毒株保持了LaSota亲本株的低致病性和高滴度鸡胚生长特性;重组病毒rLa-CDV-H接种12周龄比格犬后,可以诱导显著的CDV中和抗体反应.本研究表明重组病毒rLa-CDV-H具有作为犬瘟热重组病毒活载体疫苗的潜力.     

TaqMan~T-PCR对水疱性口炎病毒的鉴定检测

水疱性口炎分为印第安那型 ( Indiana)和新泽西型 ( New Jersey)。这两种血清型病毒的快速和可靠的鉴别对该病的诊断、检疫、分子流行病学调查和监测至关重要。文章按照 VSV核蛋白基因序列 ,设计了一对两型通用引物和两型各自特异性探针。研究建立了 VSV实时荧光定量 PCR检测方法 ,对 VSV细胞培养物、人工感染实验动物组织、血清样品 ,以及系列稀释的不同 TCID50 样品、其它相关或相似病毒进行鉴定 ,同时与常规 PCR、病毒分离试验作了比较。Taq Man○R RT-PCR的特异性和敏感性相当于或优于对照方法。重复性和稳定性试验证实 ,该方法可靠。每个试验中设立阳性、阴性对照和标准稀释度对照 ,使试验结果可对病毒 RNA作准确定量 ,并可在 4h内获得结果。研究结果表明 ,Taq Man○R RT-PCR方法是一种特异性强、敏感性高、快速安全的定量检测方法。因此 ,可以作为 VSV的快速检测和定型。     

非节段负链RNA病毒作为疫苗载体研究进展

负链RAN病毒的反向遗传系统建立以后,非节段负链RNA病毒作为疫苗载体的研究取得了重要进展.文章从病毒载体的构建策略、插入基因在载体中的位置、插入片段的大小、数量以及外源基因的表达对载体的毒性作用进行了综述;对外源糖蛋白整合到病毒粒子上对载体的影响,通过不同的方法和途径来提高载体疫苗的免疫效果方面进行阐述.     

VSV的RT-PCR快速检测方法的建立

选取水泡性口炎病毒 N基因序列 ,设计 1对引物 ,建立检测水泡性口炎病毒的 RT- PCR方法。对VSV各毒株进行检测 ,结果均为阳性 ,而对反刍动物病毒性疾病相关病毒进行检测 ,结果均为阴性。结果表明所建立的 RT- PCR技术可用于水泡性口炎的诊断和流行病学调查     

Experimental vesicular stomatitis virus infection of swine: Extent of infection and immunological response

Swine, a natural host species for infection by vesicular stomatitis virus (VSV), were infected with VSV-New Jersey (VSV-NJ) serotype virus obtained from a recent field isolate. Tissues collected from the infected pigs were examined for the presence of infective virus, for viral antigens, and/or for viral nucleic acid. Infective virus could be recovered from tissues near the site of infection for as long as 6 days after the primary infection with VSV. However, no infective virus was recovered following hypothermia induced 11 weeks after infection, or following a secondary challenge with virus 22 weeks after initial infection. Immunofluorescence tests for viral antigens and nucleic acid hybridization assays failed to detect viral antigens or nucleic acids in tissues from which no infective virus could be recovered. Titers of serum-neutralizing antibody peaked 3–5 weeks after infection and then fell slightly until the secondary infection which caused a rapid anamnestic response. Peripheral blood mononuclear cells (PBM) tested 3, 5, 8 or 18 weeks after primary infection all produced readily detectable antigen-specific proliferative responses when cultured with VSV. Thus, although direct tests failed to demonstrate persistence of virus after infection, the humoral and cellular immune response remained elevated for months. Infective VSV was not required to stimulate the proliferative response since UV-inactivated VSV was immunogenic in these in vitro tests. Following primary infection, antigen-specific proliferative responses could be stimulated by several strains of VSV-NJ, but not by VSV-Indiana (VSV-Ind) serotype virus. Secondary infection had relatively little effect on the proliferative response to VSV-NJ strains, but it did cause the PBM to gain responsiveness to VSV-Ind.     

Vesicular stomatitis virus infection and neuropathogenesis in the murine model are associated with apoptosis

This study examines apoptosis and viral neuropathogenesis in a murine model infected with vesicular stomatitis virus (VSV). VSV induces apoptotic cell death in cultured cell lines, raising the possibility that apoptosis of infected neurons and other target cells may contribute to disease and mortality. To determine whether or not VSV induces apoptosis in neural tissues, mice were inoculated intranasally with VSV. At 24, 48, 72, 96, and 120 hours postinfection, brain tissues were assayed for the presence of viral RNA by in situ hybridization and viral antigen by immunohistochemistry. Apoptosis was identified by in situ terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling and electron microscopy. Viral replication and lesions were observed predominantly in central nervous system neurons. Apoptotic cell death was restricted to the same regions of the brain in which infected cells and tissue injury were identified. Results suggest that VSV-induced apoptosis is a mechanism causing cell death, tissue injury, and mortality in VSV-infected mice.     

An enzyme-linked immunosorbent assay for the detection of bovine antibodies to vesicular stomatitis virus

An indirect enzyme-linked immunosorbent assay (ELISA) was developed to detect bovine antibody to vesicular stomatitis virus (VSV). Serum samples from cows experimentally infected with the New Jersey serotype of VSV (VSV-NJ) were assayed by the ELISA and serum-neutralization (SN) assay. The ELISA was as sensitive as the SN assay in detecting bovine antibody to VSV. The correlation between SN titers and ELISA values at absorbance at 405 nm was statistically significant. The ELISA was not specific for VSV-NJ, however, and could detect serum samples positive to the Indiana serotype of VSV that had SN titers of greater than or equal to 480. Nonspecific reactions were due to cross-reactive group-specific viral proteins that are shared by both serotypes. The cross-reactivity allows the use of a single rapid test in identifying both serotypes of VSV from the other exotic vesicular diseases, especially foot-and-mouth disease. The ELISA titers of serum samples positive for VSV-NJ were comparable with the corresponding SN titers of each sample. The sensitivity, rapidity, and ease of the ELISA system and the use of a single test in identifying both serotypes of VSV from the other exotic vesicular diseases make this ELISA suitable as a rapid diagnostic assay for VS.     

Prokaryotic Expression and Immunogenicity Analysis of N Protein from Vesicular Stomatitis Virus

This study was aimed to clone and express the specific antigen nucleoprotein (N) of vesicular stomatitis virus (VSV), and then purify and analyze its immunogenicity. Based on published VSV genome N gene sequence in GenBank, two kinds of N genes of VSV with different serotypes were synthesized, respectively. After sequence analysis, one pair of specific primers was designed and synthesized, N gene fragment with about 1 300 bp length was amplified by PCR, and subcloned into pCold Ⅰ expression vector. The recombinant N protein was induced with IPTG and purified by Ni-NTA. The results of SDS-PAGE showed that the N gene was successfully expressed in E. coli and the molecular weight of protein was 50 ku; The results of Western blotting showed that this recombined protein specifically reacted with polyclonal antibody serum of VSV. The recombinant vector with VSV-IND and VSV-NJ were successfully constructed, and the N protein was solubly expressed in E. coli, and the purified protein demonstrated promising immunogenicity.     

水泡性口炎病毒N蛋白原核表达及免疫原性分析

本研究旨在克隆和表达水泡性口炎病毒（vesicular stomatitis virus,VSV）特异性抗原N蛋白,进而纯化并分析其免疫原性。根据GenBank中已发表的VSV基因组N基因序列,分别合成VSV两种不同血清型的N基因,经序列对比分析后,设计合成1对特异性引物,PCR扩增获得约1 300 bp的N基因片段,将目的片段亚克隆至pCold Ⅰ原核表达载体中,经IPTG诱导表达后,采用Ni-NTA树脂亲和层析法纯化重组N蛋白。SDS-PAGE分析表明,N基因在大肠杆菌中得到表达,蛋白大小约为50 ku;Western blotting检测结果表明,该重组蛋白与VSV多克隆抗体发生特异性反应。本试验成功构建了VSV-IND和VSV-NJ的原核表达载体,实现了N蛋白在大肠杆菌中的可溶性表达,纯化后的重组蛋白具有良好的免疫原性。