动物水泡性口炎病毒的抗原性

动物水泡性口炎病毒(VSV)引起动物水泡性疾病.VSV有两个主要抗原群是核酸蛋白和G蛋白抗原.G蛋白因为能产生中和性抗体被认为是在发动抑制病毒感染方面起主要作用.已经证实VSV 的New Jersey 株中产生独立的中和性单克隆抗体的抗原决定蔟分布在G 蛋白的193～289氨基酸之间.     

Endosomal proteolysis of the Ebola virus glycoprotein is necessary for infection

Ebola virus (EboV) causes rapidly fatal hemorrhagic fever in humans and there is currently no effective treatment. We found that the infection of African green monkey kidney (Vero) cells by vesicular stomatitis viruses bearing the EboV glycoprotein (GP) requires the activity of endosomal cysteine proteases. Using selective protease inhibitors and protease-deficient cell lines, we identified an essential role for cathepsin B (CatB) and an accessory role for cathepsin L (CatL) in EboV GP-dependent entry. Biochemical studies demonstrate that CatB and CatL mediate entry by carrying out proteolysis of the EboV GP subunit GP1 and support a multistep mechanism that explains the relative contributions of these enzymes to infection. CatB and CatB/CatL inhibitors diminish the multiplication of infectious EboV-Zaire in cultured cells and may merit investigation as anti-EboV drugs.     

Conserved eukaryotic fusogens can fuse viral envelopes to cells

Caenorhabditis elegans proteins AFF-1 and EFF-1 [C. elegans fusion family (CeFF) proteins] are essential for developmental cell-to-cell fusion and can merge insect cells. To study the structure and function of AFF-1, we constructed vesicular stomatitis virus (VSV) displaying AFF-1 on the viral envelope, substituting the native fusogen VSV glycoprotein. Electron microscopy and tomography revealed that AFF-1 formed distinct supercomplexes resembling pentameric and hexameric "flowers" on pseudoviruses. Viruses carrying AFF-1 infected mammalian cells only when CeFFs were on the target cell surface. Furthermore, we identified fusion family (FF) proteins within and beyond nematodes, and divergent members from the human parasitic nematode Trichinella spiralis and the chordate Branchiostoma floridae could also fuse mammalian cells. Thus, FF proteins are part of an ancient family of cellular fusogens that can promote fusion when expressed on a viral particle.     

水泡性口炎的发病机理与防制

水泡性口炎(VS)是由水泡性口炎病毒(VSV)引起马、牛和猪等动物的一种重要传染病。临床表现为口腔黏膜、乳房和蹄部冠状带皮肤出现水泡和溃疡。水泡性口炎不但能感染动物,而且能够感染人,被国际兽医局(OIE)列为A类传染病。因此,对VSV致病机理的研究有着重要的社会经济和公共卫生意义。从病原、流行病学、病理变化、临床症状等方面对水泡性口炎进行综述。     

Identity of HeLa cell determinants acquired by vesicular stomatitis virus with a tumor antigen

Growth of vesicular stomatitis virus (VSV) in HeLa cells results in progeny containing non-VSV antigens with a molecular weight around 75,000. The non-VSV antigens were detected by antiserums to HeLa cell determinants. These antiserums precipitate whole virions but do not neutralize them. Because one of the antiserums is directed to a tumor-specific surface antigen of HeLa cells, it appears that VSV specifically acquires such antigens during its passage through human tumor cells.     

Crystal structure of the low-pH form of the vesicular stomatitis virus glycoprotein G

The vesicular stomatitis virus has an atypical membrane fusion glycoprotein (G) exhibiting a pH-dependent equilibrium between two forms at the virus surface. Membrane fusion is triggered during the transition from the high- to low-pH form. The structure of G in its low-pH form shows the classic hairpin conformation observed in all other fusion proteins in their postfusion conformation, in spite of a novel fold combining features of fusion proteins from classes I and II. The structure provides a framework for understanding the reversibility of the G conformational change. Unexpectedly, G is homologous to gB of herpesviruses, which raises important questions on viral evolution.     

Homologous viral interference: induction by RNA from defective particles of vesicular stomatitis virus

The viral RNA isolated from the defective particles of vesicular stomatitis virus was capable of interfering with the replication of this virus in chick embryo cells. The data indicate that the interfering ability of the defective particles of this virus is due to their nucleic acid component.     

Vesicular stomatitis virus replication in human leukocyte cultures: enhancement by phytohemagglutinin

The replication of vesicular stomatitis virus in human leukocyte cultures shows that virus yields can be enhanced 6-to 180-fold by treating the leukocyte cultures with phytohemagglutinin prior to virus inoculation. Data suggest that a substance is produced in phytohemagglutinin-treated leukocyte cultures which is capable, on transfer to fresh leukocytes, of inducing blast cell formation and enhancing virus replication.     

Mechanism of membrane anchoring affects polarized expression of two proteins in MDCK cells

The signals that direct membrane proteins to the apical or basolateral plasma membrane domains of polarized epithelial cells are not known. Several of the class of proteins anchored in the membrane by glycosyl-phosphatidylinositol (GPI) are expressed on the apical surface of such cells. However, it is not known whether the mechanism of membrane anchorage or the polypeptide sequence provides the sorting information. The conversion of the normally basolateral vesicular stomatitis virus glycoprotein (VSV G) to a GPI-anchored protein led to its apical expression. Conversely, replacement of the GPI anchor of placental alkaline phosphatase with the transmembrane and cytoplasmic domains of VSV G shifted its expression from the apical to the basolateral surface. Thus, the mechanism of membrane anchorage can determine the sorting of proteins to the apical or basolateral surface, and the GPI anchor itself may provide an apical transport signal.     

Crystal structure of glycoprotein B from herpes simplex virus 1

Glycoprotein B (gB) is the most conserved component of the complex cell-entry machinery of herpes viruses. A crystal structure of the gB ectodomain from herpes simplex virus type 1 reveals a multidomain trimer with unexpected homology to glycoprotein G from vesicular stomatitis virus (VSV G). An alpha-helical coiled-coil core relates gB to class I viral membrane fusion glycoproteins; two extended beta hairpins with hydrophobic tips, homologous to fusion peptides in VSV G, relate gB to class II fusion proteins. Members of both classes accomplish fusion through a large-scale conformational change, triggered by a signal from a receptor-binding component. The domain connectivity within a gB monomer would permit such a rearrangement, including long-range translocations linked to viral and cellular membranes.     

(S)-9-(2,3-Dihydroxypropyl)adenine: An Aliphatic Nucleoside Analog with Broad-Spectrum Antiviral Activity

(S)-9-(2,3-Dihydroxypropyl)adenine, a novel nucleoside analog, the sugar moiety of which is replaced by an aliphatic chain, inhibits the replication in vitro of several DNA and RNA viruses, including vaccinia, herpes simplex (types 1 and 2), measles, and vesicular stomatitis. It is also effective in vivo in reducing the mortality rate of mice inoculated intranasally with vesicular stomatitis virus.     

重组水泡性口炎病毒基质蛋白制备及ELISA检测方法的建立

水泡性口炎由水泡性口炎病毒(VSV)引起。VSV基因组编码5个结构蛋白,其中基质蛋白(matrix protein,M)是其重要毒力因子,可阻遏宿主细胞mRNA由胞核向细胞质的转运,并抑制感染病毒的细胞产生I型干扰素IFNα/β,使病毒得以快速繁殖。本实验克隆了印第安那型VSV的M基因,在大肠杆菌表达系统中表达制备重组M蛋白,以M蛋白为抗原建立了检测特异M蛋白抗体的间接ELISA方法。采用建立的ELISA方法分析了VSV感染小鼠体内M蛋白抗体的变化规律。     

两种细胞株滴定重组猪α干扰素效价的比较研究

采用水泡性口炎病毒（VSV）作为攻击病毒,以微量细胞病变抑制法对同批次不同浓度的8组重组猪α干扰素（rPoIFN-α）样品进行了效价检测,以中国药品生物制品检定所指定使用的标化重组人α干扰素为效价滴定的参比标准,对在牛肾细胞（MDBK）株和人喉癌上皮细胞（HEp-2）株所得结果进行比较,并对细胞与待测样品按＂一步法＂和先加细胞,待细胞长满单层再加待测样品的＂两步法＂所得的rPoIFN-α抗病毒效价进行比较。结果表明：MDBK细胞株与HEp-2细胞株对于rPoIFN-α抗病毒活性检测结果无显著性差异,均可用于rPoIFN-α抗病毒活性的检测,重组人α干扰素滴定系统可用于rPoIFN-α效价检测。两种加样方法所得结果基本相同,推荐使用＂一步法＂。     

抗水泡性口炎病毒的单克隆抗体制备及生物学特性鉴定

纯化浓缩水泡性口炎病毒(VSV-IN)作为免疫原,免疫Balb/c小鼠,当免疫抗体效价达到融合要求时,在融合前3d尾静脉加强注射免疫原,取免疫的Balb/c小鼠的脾脏与SP2/0细胞在PEG4000作用下,融合、筛选、克隆获得5株稳定分泌抗VSV单克隆抗体的杂交瘤细胞株。Balb/c小鼠腹腔注射杂交瘤细胞株,收集腹水初步纯化,获5株单克隆抗体,亚类鉴定分属IgG2a和IgM型。     

水泡性口炎病毒人工感染小白鼠的免疫病理学研究

[目的]探讨水泡性口炎病毒在动物体内的致病机制。[方法]利用H.E、免疫组织化学染色法,研究了水泡性口炎病毒感染小白鼠的免疫病理过程。[结果]病变以肺脏变化最明显,脑次之,呈肺淤血、出血、水肿及支气管肺炎变化,大脑皮质有脓性坏死灶。免疫组化染色显示,肺、脑部和脊髓出现了阳性反应,脑的阳性率高。[结论]水泡性口炎病毒对小白鼠的致病性主要表现在肺脏和脑部。     

水泡性口炎病毒诱导BHK-21细胞凋亡的初步研究

采用倒置相差显微镜、电子显微镜、琼脂糖凝胶电泳等技术研究水泡性口炎病毒诱导BHK-21细胞凋亡．形态学观察结果显示,水泡性口炎病毒感染BHK-21细胞的形态变化具有较典型的凋亡特征,如细胞膜内陷、核染色质凝集边聚等;琼脂糖凝胶电泳出现180-200bp整倍数的DNA梯形带．上述结果表明水泡性口炎病毒可诱导BHK-21细胞凋亡。     

水泡性口炎病毒感染BHK-21细胞的超微结构

应用电镜技术对水泡性口炎病毒在BHK-21上的形态发生和增殖规律进行观察．结果表明：VSV能导致BHK-21细胞圆缩,胞浆严重空泡化,线粒体嵴断裂及空泡化;病毒在细胞浆内复制、增殖,在细胞膜和线粒体膜以出芽方式获得囊膜而成熟．     

Vesicular stomatitis virus (Indiana serotype): transovarial transmission by phlebotomine sandlies

Transovarial transmission of vesicular stomatitis virus (Indiana serotype) by experimentally infected Lutzomyia trapidoi and Lutzomyia ylephiletrix to their progeny was demonstrated. Virus was recovered from all developmental stages; mean virus titers from egg to first generation adult showed a four-log increase, indicating that virus multiplication occurred during development of the sandflies. Virus titers in first generation adult females were comparable to those found in their parents. These infected female sandflies transmitted vesicular stomatitus virus Indiana by bite to susceptible animals and transmitted the virus transovarially to their offspring (second generation). Results demonstrate a possible mechanism for transmission and maintenance of this virus in nature without a vertebrate (heat) host reservoir.     

Transmission of vesicular stomatitis virus from infected to noninfected black flies co-feeding on nonviremic deer mice

Vesicular stomatitis is an economically important arboviral disease of livestock. Viremia is absent in infected mammalian hosts, and the mechanism by which insects become infected with the causative agents, vesicular stomatitis viruses, remains unknown. Because infected and noninfected insects potentially feed on the same host in nature, infected and noninfected black flies were allowed to feed on the same host. Viremia was not detected in the host after infection by a black fly bite, but because noninfected black flies acquired the virus while co-feeding on the same host with infected black flies, it is concluded that a viremic host is not necessary for an insect to be infected with the virus. Thus co-feeding is a mechanism of infection for an insect-transmitted virus.