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Sample records for virus protein expression

  1. Protection against myxomatosis and rabbit viral hemorrhagic disease with recombinant myxoma viruses expressing rabbit hemorrhagic disease virus capsid protein.

    OpenAIRE

    Bertagnoli, Stéphane; Gelfi, Jacqueline; Le Gall, Ghislaine; Boilletot, Eric; Vautherot, Jean-François; Rasschaert, Denis; Laurent, Sylvie; Petit, Frédérique; Boucraut-Baralon, Corine; Milon, Alain

    1996-01-01

    Two myxoma virus-rabbit hemorrhagic disease virus (RHDV) recombinant viruses were constructed with the SG33 strain of myxoma virus to protect rabbits against myxomatosis and rabbit viral hemorrhagic disease. These recombinant viruses expressed the RHDV capsid protein (VP60). The recombinant protein, which is 60 kDa in size, was antigenic, as revealed by its reaction in immunoprecipitation with antibodies raised against RHDV. Both recombinant viruses induced high levels of RHDV- and myxoma vir...

  2. Parainfluenza virus 5 expressing the G protein of rabies virus protects mice after rabies virus infection.

    Science.gov (United States)

    Huang, Ying; Chen, Zhenhai; Huang, Junhua; Fu, ZhenFang; He, Biao

    2015-03-01

    Rabies remains a major public health threat around the world. Once symptoms appear, there is no effective treatment to prevent death. In this work, we tested a recombinant parainfluenza virus 5 (PIV5) strain expressing the glycoprotein (G) of rabies (PIV5-G) as a therapy for rabies virus infection: we have found that PIV5-G protected mice as late as 6 days after rabies virus infection. PIV5-G is a promising vaccine for prevention and treatment of rabies virus infection. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. Protection against myxomatosis and rabbit viral hemorrhagic disease with recombinant myxoma viruses expressing rabbit hemorrhagic disease virus capsid protein.

    Science.gov (United States)

    Bertagnoli, S; Gelfi, J; Le Gall, G; Boilletot, E; Vautherot, J F; Rasschaert, D; Laurent, S; Petit, F; Boucraut-Baralon, C; Milon, A

    1996-08-01

    Two myxoma virus-rabbit hemorrhagic disease virus (RHDV) recombinant viruses were constructed with the SG33 strain of myxoma virus to protect rabbits against myxomatosis and rabbit viral hemorrhagic disease. These recombinant viruses expressed the RHDV capsid protein (VP60). The recombinant protein, which is 60 kDa in size, was antigenic, as revealed by its reaction in immunoprecipitation with antibodies raised against RHDV. Both recombinant viruses induced high levels of RHDV- and myxoma virus-specific antibodies in rabbits after immunization. Inoculations by the intradermal route protected animals against virulent RHDV and myxoma virus challenges.

  4. Assessing the expression of chicken anemia virus proteins in plants

    NARCIS (Netherlands)

    Lacorte, C.C.; Lohuis, H.; Goldbach, R.W.; Prins, M.W.

    2007-01-01

    Chicken anemia virus (CAV) is an important pathogen of chicken worldwide, causing severe anemia and immunodeficiency. Its small single-stranded DNA genome (2.3 kb) encodes three proteins: VP1, the only structural protein, VP2, a protein phosphatase, and VP3, also known as apoptin, which induces

  5. A DNA vaccine expressing PB1 protein of influenza A virus protects mice against virus infection.

    Science.gov (United States)

    Košík, Ivan; Krejnusová, Ingrid; Práznovská, Margaréta; Poláková, Katarína; Russ, Gustáv

    2012-05-01

    Although influenza DNA vaccine research has focused mainly on viral hemagglutinin and has led to promising results, other virion proteins have also shown some protective potential. In this work, we explored the potential of a DNA vaccine based on the PB1 protein to protect BALB/c mice against lethal influenza A virus infection. The DNA vaccine consisted of pTriEx4 plasmid expressing PB1. As a positive control, a pTriEx4 plasmid expressing influenza A virus HA was used. Two weeks after three subcutaneous doses of DNA vaccine, the mice were challenged intranasally with 1 LD50 of A/Puerto Rico/8/34 (H1N1) virus, and PB1- and HA-specific antibodies, survival rate, body weight change, viral mRNA load, infectious virus titer in the lungs, cytokines IL-2, IL-4 and IL-10, and granzyme-B were measured. The results showed that (i) the PB1-expressing DNA vaccine provided a fair protective immunity in the mouse model and (ii) viral structural proteins such as PB1 represent promising antigens for DNA vaccination against influenza A.

  6. High-efficiency protein expression in plants from agroinfection-compatible Tobacco mosaic virus expression vectors

    Directory of Open Access Journals (Sweden)

    Lindbo John A

    2007-08-01

    Full Text Available Abstract Background Plants are increasingly being examined as alternative recombinant protein expression systems. Recombinant protein expression levels in plants from Tobacco mosaic virus (TMV-based vectors are much higher than those possible from plant promoters. However the common TMV expression vectors are costly, and at times technically challenging, to work with. Therefore it was a goal to develop TMV expression vectors that express high levels of recombinant protein and are easier, more reliable, and more cost-effective to use. Results We have constructed a Cauliflower mosaic virus (CaMV 35S promoter-driven TMV expression vector that can be delivered as a T-DNA to plant cells by Agrobacterium tumefaciens. Co-introduction (by agroinfiltration of this T-DNA along with a 35S promoter driven gene for the RNA silencing suppressor P19, from Tomato bushy stunt virus (TBSV resulted in essentially complete infection of the infiltrated plant tissue with the TMV vector by 4 days post infiltration (DPI. The TMV vector produced between 600 and 1200 micrograms of recombinant protein per gram of infiltrated tissue by 6 DPI. Similar levels of recombinant protein were detected in systemically infected plant tissue 10–14 DPI. These expression levels were 10 to 25 times higher than the most efficient 35S promoter driven transient expression systems described to date. Conclusion These modifications to the TMV-based expression vector system have made TMV vectors an easier, more reliable and more cost-effective way to produce recombinant proteins in plants. These improvements should facilitate the production of recombinant proteins in plants for both research and product development purposes. The vector should be especially useful in high-throughput experiments.

  7. Cutting Edge: Innate Immune Augmenting Vesicular Stomatitis Virus Expressing Zika Virus Proteins Confers Protective Immunity.

    Science.gov (United States)

    Betancourt, Dillon; de Queiroz, Nina M G P; Xia, Tianli; Ahn, Jeonghyun; Barber, Glen N

    2017-04-15

    Zika virus (ZIKV) has become a serious public health concern because of its link to brain damage in developing human fetuses. Recombinant vesicular stomatitis virus (rVSV) was shown to be a highly effective and safe vector for the delivery of foreign immunogens for vaccine purposes. In this study, we generated rVSVs (wild-type and attenuated VSV with mutated matrix protein [VSVm] versions) that express either the full length ZIKV envelope protein (ZENV) alone or include the ZENV precursor to the membrane protein upstream of the envelope protein, and our rVSV-ZIKV constructs showed efficient immunogenicity in murine models. We also demonstrated maternal protective immunity in challenged newborn mice born to female mice vaccinated with VSVm-ZENV containing the transmembrane domain. Our data indicate that rVSVm may be a suitable strategy for the design of effective vaccines against ZIKV. Copyright © 2017 by The American Association of Immunologists, Inc.

  8. Differential Protein Expressions in Virus-Infected and Uninfected Trichomonas vaginalis.

    Science.gov (United States)

    He, Ding; Pengtao, Gong; Ju, Yang; Jianhua, Li; He, Li; Guocai, Zhang; Xichen, Zhang

    2017-04-01

    Protozoan viruses may influence the function and pathogenicity of the protozoa. Trichomonas vaginalis is a parasitic protozoan that could contain a double stranded RNA (dsRNA) virus, T. vaginalis virus (TVV). However, there are few reports on the properties of the virus. To further determine variations in protein expression of T. vaginalis, we detected 2 strains of T. vaginalis; the virus-infected (V+) and uninfected (V-) isolates to examine differentially expressed proteins upon TVV infection. Using a stable isotope N-terminal labeling strategy (iTRAQ) on soluble fractions to analyze proteomes, we identified 293 proteins, of which 50 were altered in V+ compared with V- isolates. The results showed that the expression of 29 proteins was increased, and 21 proteins decreased in V+ isolates. These differentially expressed proteins can be classified into 4 categories: ribosomal proteins, metabolic enzymes, heat shock proteins, and putative uncharacterized proteins. Quantitative PCR was used to detect 4 metabolic processes proteins: glycogen phosphorylase, malate dehydrogenase, triosephosphate isomerase, and glucose-6-phosphate isomerase, which were differentially expressed in V+ and V- isolates. Our findings suggest that mRNA levels of these genes were consistent with protein expression levels. This study was the first which analyzed protein expression variations upon TVV infection. These observations will provide a basis for future studies concerning the possible roles of these proteins in host-parasite interactions.

  9. Recombinant measles viruses expressing respiratory syncytial virus proteins induced virus-specific CTL responses in cotton rats.

    Science.gov (United States)

    Yamaji, Yoshiaki; Nakayama, Tetsuo

    2014-07-31

    Respiratory syncytial virus (RSV) is a common cause of serious lower respiratory tract illnesses in infants. Natural infections with RSV provide limited protection against reinfection because of inefficient immunological responses that do not induce long-term memory. RSV natural infection has been shown to induce unbalanced immune response. The effective clearance of RSV is known to require the induction of a balanced Th1/Th2 immune response, which involves the induction of cytotoxic T lymphocytes (CTL). In our previous study, recombinant AIK-C measles vaccine strains MVAIK/RSV/F and MVAIK/RSV/G were developed, which expressed the RSV fusion (F) protein or glycoprotein (G). These recombinant viruses elicited antibody responses against RSV in cotton rats, and no infectious virus was recovered, but small amounts of infiltration of inflammatory cells were observed in the lungs following RSV challenge. In the present study, recombinant AIK-C measles vaccine strains MVAIK/RSV/M2-1 and MVAIK/RSV/NP were developed, expressing RSV M2-1 or Nucleoprotein (NP), respectively. These viruses exhibited temperature-sensitivity (ts), which was derived from AIK-C, and expressed respective RSV antigens. The intramuscular inoculation of cotton rats with the recombinant measles virus led to the induction of CD8(+) IFN-γ(+) cells. No infectious virus was recovered from a lung homogenate following the challenge. A Histological examination of the lungs revealed a significant reduction in inflammatory reactions without alveolar damage. These results support the recombinant measles viruses being effective vaccine candidates against RSV that induce RSV-specific CTL responses with or without the development of an antibody response. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Orsay virus utilizes ribosomal frameshifting to express a novel protein that is incorporated into virions

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Hongbing; Franz, Carl J.; Wu, Guang; Renshaw, Hilary; Zhao, Guoyan [Departments of Molecular Microbiology and Pathology and Immunology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110 (United States); Firth, Andrew E. [Department of Pathology, University of Cambridge, Cambridge CB2 1QP (United Kingdom); Wang, David, E-mail: davewang@borcim.wustl.edu [Departments of Molecular Microbiology and Pathology and Immunology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110 (United States)

    2014-02-15

    Orsay virus is the first identified virus that is capable of naturally infecting Caenorhabditis elegans. Although it is most closely related to nodaviruses, Orsay virus differs from nodaviruses in its genome organization. In particular, the Orsay virus RNA2 segment encodes a putative novel protein of unknown function, termed delta, which is absent from all known nodaviruses. Here we present evidence that Orsay virus utilizes a ribosomal frameshifting strategy to express a novel fusion protein from the viral capsid (alpha) and delta ORFs. Moreover, the fusion protein was detected in purified virus fractions, demonstrating that it is most likely incorporated into Orsay virions. Furthermore, N-terminal sequencing of both the fusion protein and the capsid protein demonstrated that these proteins must be translated from a non-canonical initiation site. While the function of the alpha–delta fusion remains cryptic, these studies provide novel insights into the fundamental properties of this new clade of viruses. - Highlights: • Orsay virus encodes a novel fusion protein by a ribosomal frameshifting mechanism. • Orsay capsid and fusion protein is translated from a non-canonical initiation site. • The fusion protein is likely incorporated into Orsay virions.

  11. Plant virus expression vectors set the stage as production platforms for biopharmaceutical proteins.

    Science.gov (United States)

    Hefferon, Kathleen Laura

    2012-11-10

    Transgenic plants present enormous potential as a cost-effective and safe platform for large-scale production of vaccines and other therapeutic proteins. A number of different technologies are under development for the production of pharmaceutical proteins from plant tissues. One method used to express high levels of protein in plants involves the employment of plant virus expression vectors. Plant virus vectors have been designed to carry vaccine epitopes as well as full therapeutic proteins such as monoclonal antibodies in plant tissue both safely and effectively. Biopharmaceuticals such as these offer enormous potential on many levels, from providing relief to those who have little access to modern medicine, to playing an active role in the battle against cancer. This review describes the current design and status of plant virus expression vectors used as production platforms for biopharmaceutical proteins. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Recombinant rabies virus expressing the H protein of canine distemper virus protects dogs from the lethal distemper challenge.

    Science.gov (United States)

    Wang, Feng-Xue; Zhang, Shu-Qin; Zhu, Hong-Wei; Yang, Yong; Sun, Na; Tan, Bin; Li, Zhen-Guang; Cheng, Shi-Peng; Fu, Zhen F; Wen, Yong-Jun

    2014-12-05

    The rabies virus (RV) vector LBNSE expressing foreign antigens have shown considerable promise as vaccines against viral and bacteria diseases, which is effective and safe. We produced a new RV-based vaccine vehicle expressing 1.824 kb hemagglutinin (H) gene of the canine distemper virus (CDV) by reverse genetics technology. The recombinant virus LBNSE-CDV-H retained growth properties similar to those of vector LBNSE both in BSR and mNA cell culture. The H gene of CDV was expressed and detected by immunostaining. To compare the immunogenicity of LBNSE-CDV-H, dogs were immunized with each of these recombinant viruses by intramuscular (i.m.). The dogs were bled at third weeks after the immunization for the measurement of virus neutralizing antibody (VNA) and then challenged with virulent virus (ZJ 7) at fourth weeks. The parent virus (LBNSE) without expression of any foreign molecules was included for comparison. Dogs inoculated with LBNSE-CDV-H showed no any signs of disease and exhibited seroconversion against both RV and CDV H protein. The LBNSE-CDV-H did not cause disease in dogs and conferred protection from challenge with a lethal wild type CDV strain, demonstrating its potential value for wildlife conservation efforts. Together, these studies suggest that recombinant RV expressing H protein from CDV stimulated high levels of adaptive immune responses (VNA), and protected all dogs challenge infection. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Temporal expression and immunogold localization of Plodia interpunctella granulosis virus structural proteins

    Science.gov (United States)

    Funk, C. J.; Consigli, R. A.; Spooner, B. S. (Principal Investigator)

    1993-01-01

    Monospecific antisera were produced against four structural proteins (VP12, VP17, VP31, and granulin) of the Plodia interpunctella granulosis virus using polypeptides derived by sodium dodecyl sulfate-polyacrylamide gel electrophoresis or acid extraction. The antisera were shown to be specific on immunoblots of SDS-PAGE separated granulosis virus and were further used to detect structural proteins in infected fat body lysates. Immunoblots of fat body lysates from early stages of infection indicated that VP12, VP17, VP31, and granulin were expressed by 2.5 days post-infection. Immunogold labeling of the virus using the monospecific antisera and electron microscopy confirmed earlier reports that granulin is located in the protein matrix, V17 is an envelope protein, and VP31 is a capsid protein.

  14. [Rapid selection of recombinant orf virus expression vectors using green fluorescent protein].

    Science.gov (United States)

    Zhang, Jiachun; Guo, Xianfeng; Zhang, Min; Wu, Feifan; Peng, Yongzheng

    2016-01-01

    To construct a universal, highly attenuated orf virus expression vector for exogenous genes using green fluorescent protein (GFP) as the reporter gene. The flanking regions of the ORFV132 of orf virus DNA were amplified by PCR to construct the shuttle plasmid pSPV-132LF-EGFP-132RF. The shuttle plasmid was transfected into OFTu cells and GFP was incorporated into orf virus IA82Delta 121 by homologous recombination. The recombinant IA82Delta121-V was selected by green fluorescent signal. The deletion gene was identified by PCR and sequencing. The effects of ORFV132 knockout were evaluated by virus titration and by observing the proliferation of the infected vascular endothelial cells in vitro. The recombinant orf virus IA82Delta121-V was obtained successfully and quickly, and the deletion of ORFV132 did not affect the replication of the virus in vitro but reduced its virulence. Green fluorescent protein is a selectable marker for rapid, convenient and stable selection of the recombinant viruses. Highly attenuated recombinant orf virus IA82Delta121-V can serve as a new expression vector for exogenous genes.

  15. Hepatitis C virus expressing reporter tagged NS5A protein

    DEFF Research Database (Denmark)

    2014-01-01

    Hepatitis C reporter viruses containing Core through NS2 of prototype isolates of all major HCV genotypes and the remaining genes of isolate JFH1, by insertion of reporter genes in domain III of HCV NS5A were developed. A deletion upstream of the inserted reporter gene sequence conferred favorable...... growth kinetics in Huh7.5 cells to these viruses. These reporter viruses can be used for high throughput analysis of drug and vaccine candidates as well as patient samples. JFH1-based intergenotypic recombinants with genotype specific homotypic 5'UTR, or heterotypic 5'UTR (either of genotype 1a (strain H...

  16. Expression of RNA virus proteins by RNA polymerase II dependent expression plasmids is hindered at multiple steps

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    Überla Klaus

    2007-06-01

    Full Text Available Abstract Background Proteins of human and animal viruses are frequently expressed from RNA polymerase II dependent expression cassettes to study protein function and to develop gene-based vaccines. Initial attempts to express the G protein of vesicular stomatitis virus (VSV and the F protein of respiratory syncytial virus (RSV by eukaryotic promoters revealed restrictions at several steps of gene expression. Results Insertion of an intron flanked by exonic sequences 5'-terminal to the open reading frames (ORF of VSV-G and RSV-F led to detectable cytoplasmic mRNA levels of both genes. While the exonic sequences were sufficient to stabilise the VSV-G mRNA, cytoplasmic mRNA levels of RSV-F were dependent on the presence of a functional intron. Cytoplasmic VSV-G mRNA levels led to readily detectable levels of VSV-G protein, whereas RSV-F protein expression remained undetectable. However, RSV-F expression was observed after mutating two of four consensus sites for polyadenylation present in the RSV-F ORF. Expression levels could be further enhanced by codon optimisation. Conclusion Insufficient cytoplasmic mRNA levels and premature polyadenylation prevent expression of RSV-F by RNA polymerase II dependent expression plasmids. Since RSV replicates in the cytoplasm, the presence of premature polyadenylation sites and elements leading to nuclear instability should not interfere with RSV-F expression during virus replication. The molecular mechanisms responsible for the destabilisation of the RSV-F and VSV-G mRNAs and the different requirements for their rescue by insertion of an intron remain to be defined.

  17. Transient Bluetongue virus serotype 8 capsid protein expression in Nicotiana benthamiana

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    Albertha R. van Zyl

    2016-03-01

    Full Text Available Bluetongue virus (BTV causes severe disease in domestic and wild ruminants, and has recently caused several outbreaks in Europe. Current vaccines include live-attenuated and inactivated viruses; while these are effective, there is risk of reversion to virulence by mutation or reassortment with wild type viruses. Subunit or virus-like particle (VLP vaccines are safer options: VLP vaccines produced in insect cells by expression of the four BTV capsid proteins are protective against challenge; however, this is a costly production method. We investigated production of BTV VLPs in plants via Agrobacterium-mediated transient expression, an inexpensive production system very well suited to developing country use. Leaves infiltrated with recombinant pEAQ-HT vectors separately encoding the four BTV-8 capsid proteins produced more proteins than recombinant pTRA vectors. Plant expression using the pEAQ-HT vector resulted in both BTV-8 core-like particles (CLPs and VLPs; differentially controlling the concentration of infiltrated bacteria significantly influenced yield of the VLPs. In situ localisation of assembled particles was investigated by using transmission electron microscopy (TEM and it was shown that a mixed population of core-like particles (CLPs, consisting of VP3 and VP7 and VLPs were present as paracrystalline arrays in the cytoplasm of plant cells co-expressing all four capsid proteins.

  18. Expression of measles virus nucleoprotein induces apoptosis and modulates diverse functional proteins in cultured mammalian cells.

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    Ashima Bhaskar

    Full Text Available BACKGROUND: Measles virus nucleoprotein (N encapsidates the viral RNA, protects it from endonucleases and forms a virus specific template for transcription and replication. It is the most abundant protein during viral infection. Its C-terminal domain is intrinsically disordered imparting it the flexibility to interact with several cellular and viral partners. PRINCIPAL FINDINGS: In this study, we demonstrate that expression of N within mammalian cells resulted in morphological transitions, nuclear condensation, DNA fragmentation and activation of Caspase 3 eventuating into apoptosis. The rapid generation of intracellular reactive oxygen species (ROS was involved in the mechanism of cell death. Addition of ascorbic acid (AA or inhibitor of caspase-3 in the extracellular medium partially reversed N induced apoptosis. We also studied the protein profile of cells expressing N protein. MS analysis revealed the differential expression of 25 proteins out of which 11 proteins were up regulated while 14 show signs of down regulation upon N expression. 2DE results were validated by real time and semi quantitative RT-PCR analysis. CONCLUSION: These results show the pro-apoptotic effects of N indicating its possible development as an apoptogenic tool. Our 2DE results present prima facie evidence that the MV nucleoprotein interacts with or causes differential expression of a wide range of cellular factors. At this stage it is not clear as to what the adaptive response of the host cell is and what reflects a strategic modulation exerted by the virus.

  19. Expression and Purification of Coat Protein of Citrus Tristeza Virus ...

    African Journals Online (AJOL)

    clearing, leaf mottling, leaf cupping, vein corking and symptomless are observed symptoms on infected plant ..... from a litter of culture is enough to immunize rabbit (one primary injection and six booster injection in ... The molecular basis for the antigenic diversity of CTV Implications for virus detection. Proc. Flo. State Hort.

  20. Expression and Functional Characterization of Bluetongue Virus VP2 Protein: Role in Cell Entry

    OpenAIRE

    Hassan, Sharifah S; Roy, Polly

    1999-01-01

    Segment 2 of bluetongue virus (BTV) serotype 10, which encodes the outer capsid protein VP2, was tagged with the S-peptide fragment of RNase A and expressed by a recombinant baculovirus. The recombinant protein was subsequently purified to homogeneity by virtue of the S tag, and the oligomeric nature of the purified protein was determined. The data obtained indicated that the majority of the protein forms a dimer and, to a lesser extent, some trimer. The recombinant protein was used to determ...

  1. [Nonstructural protein 1 of tick-borne encephalitis virus activates the expression of immunoproteasome subunits].

    Science.gov (United States)

    Kuzmenko, Y V; Starodubova, E S; Karganova, G G; Timofeev, A V; Karpov, V L

    2016-01-01

    The interaction of viral proteins with host cell components plays an important role in antiviral immune response. One of the key steps of antiviral defense is the formation of immunoproteasomes. The effect of nonstructural protein 1 (NS1) of tick-borne encephalitis virus on the immunoproteasome formation was studied. It was shown that cell expression of NS1 does not reduce the efficacy of the immunoproteasome generation in response to interferon-γ stimulation and even increases the content of the immunoproteasome subunits without the interferon-γ treatment. Thus, NS1 of tick-borne encephalitis virus activates, rather than blocks the mechanisms of immune defense in the cell.

  2. Production of Myxoma virus gateway entry and expression libraries and validation of viral protein expression.

    Science.gov (United States)

    Smallwood, Sherin E; Rahman, Masmudur M; Werden, Steven J; Martino, Maria Fernanda; McFadden, Grant

    2011-05-01

    Invitrogen's Gateway technology is a recombination-based cloning method that allows for rapid transfer of numerous open reading frames (ORFs) into multiple plasmid vectors, making it useful for diverse high-throughput applications. Gateway technology has been utilized to create an ORF library for Myxoma virus (MYXV), a member of the Poxviridae family of DNA viruses. MYXV is the prototype virus for the genus Leporipoxvirus, and is pathogenic only in European rabbits. MYXV replicates exclusively in the host cell cytoplasm, and its genome encodes 171 ORFs. A number of these ORFs encode proteins that interfere with or modulate host defense mechanisms, particularly the inflammatory responses. Furthermore, MYXV is able to productively infect a variety of human cancer cell lines and is being developed as an oncolytic virus for treating human cancers. MYXV is therefore an excellent model for studying poxvirus biology, pathogenesis, and host tropism, and a good candidate for ORFeome development.

  3. Antagonistic Effects of Cellular Poly(C) Binding Proteins on Vesicular Stomatitis Virus Gene Expression

    Science.gov (United States)

    Dinh, Phat X.; Beura, Lalit K.; Panda, Debasis; Das, Anshuman; Pattnaik, Asit K.

    2011-01-01

    Immunoprecipitation and subsequent mass spectrometry analysis of the cellular proteins from cells expressing the vesicular stomatitis virus (VSV) P protein identified the poly(C) binding protein 2 (PCBP2) as one of the P protein-interacting proteins. To investigate the role of PCBP2 in the viral life cycle, we examined the effects of depletion or overexpression of this protein on VSV growth. Small interfering RNA-mediated silencing of PCBP2 promoted VSV replication. Conversely, overexpression of PCBP2 in transfected cells suppressed VSV growth. Further studies revealed that PCBP2 negatively regulates overall viral mRNA accumulation and subsequent genome replication. Coimmunoprecipitation and immunofluorescence microscopic studies showed that PCBP2 interacts and colocalizes with VSV P protein in virus-infected cells. The P-PCBP2 interaction did not result in reduced levels of protein complex formation with the viral N and L proteins, nor did it induce degradation of the P protein. In addition, PCBP1, another member of the poly(C) binding protein family with homology to PCBP2, was also found to interact with the P protein and inhibit the viral mRNA synthesis at the level of primary transcription without affecting secondary transcription or genome replication. The inhibitory effects of PCBP1 on VSV replication were less pronounced than those of PCBP2. Overall, the results presented here suggest that cellular PCBP2 and PCBP1 antagonize VSV growth by affecting viral gene expression and highlight the importance of these two cellular proteins in restricting virus infections. PMID:21752917

  4. Expression and Purification of Z Protein from Junín Virus

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    S. E. Goñi

    2010-01-01

    Full Text Available Arenaviridae comprises 23 recognized virus species with a bipartite ssRNA genome and an ambisense coding strategy. The virions are enveloped and include nonequimolar amounts of each genomic RNA species, designated L and S, coding for four ORFs (N, GPC, L, and Z. The arenavirus Junín (JUNV is the etiological agent of Argentine Hemorrhagic Fever, an acute disease with high mortality rate. It has been proposed that Z is the functional counterpart of the matrix proteins found in other negative-stranded enveloped RNA viruses. Here we report the optimized expression of a synthetic gene of Z protein, using three expression systems (two bacterial and a baculoviral one. One of these recombinant proteins was used to generate antibodies. A bioinformatic analysis was made where Z was subdivided into three domains. The data presented contributes methodologies for Z recombinant production and provides the basis for the development of new experiments to test its function.

  5. Expression and purification of coat protein of citrus tristeza virus ...

    African Journals Online (AJOL)

    Six colonies of TOP10 E. coli were selected and checked for the appropriate insertion of cp gene with PCR using T7F (5' TAA TAC GAC TCA CTA TAG GG 3') as forward primer and CTVCP2 as reverse primer. Two colonies having appropriate insertion were selected for transformation into BLD21 star (DE3) expression E.

  6. 4EBP-Dependent Signaling Supports West Nile Virus Growth and Protein Expression

    Science.gov (United States)

    Shives, Katherine D.; Massey, Aaron R.; May, Nicholas A.; Morrison, Thomas E.; Beckham, J. David

    2016-01-01

    West Nile virus (WNV) is a (+) sense, single-stranded RNA virus in the Flavivirus genus. WNV RNA possesses an m7GpppNm 5′ cap with 2′-O-methylation that mimics host mRNAs preventing innate immune detection and allowing the virus to translate its RNA genome through the utilization of cap-dependent translation initiation effectors in a wide variety of host species. Our prior work established the requirement of the host mammalian target of rapamycin complex 1 (mTORC1) for optimal WNV growth and protein expression; yet, the roles of the downstream effectors of mTORC1 in WNV translation are unknown. In this study, we utilize gene deletion mutants in the ribosomal protein kinase called S6 kinase (S6K) and eukaryotic translation initiation factor 4E-binding protein (4EBP) pathways downstream of mTORC1 to define the role of mTOR-dependent translation initiation signals in WNV gene expression and growth. We now show that WNV growth and protein expression are dependent on mTORC1 mediated-regulation of the eukaryotic translation initiation factor 4E-binding protein/eukaryotic translation initiation factor 4E-binding protein (4EBP/eIF4E) interaction and eukaryotic initiation factor 4F (eIF4F) complex formation to support viral growth and viral protein expression. We also show that the canonical signals of mTORC1 activation including ribosomal protein s6 (rpS6) and S6K phosphorylation are not required for WNV growth in these same conditions. Our data suggest that the mTORC1/4EBP/eIF4E signaling axis is activated to support the translation of the WNV genome. PMID:27763553

  7. 4EBP-Dependent Signaling Supports West Nile Virus Growth and Protein Expression

    Directory of Open Access Journals (Sweden)

    Katherine D. Shives

    2016-10-01

    Full Text Available West Nile virus (WNV is a (+ sense, single-stranded RNA virus in the Flavivirus genus. WNV RNA possesses an m7GpppNm 5′ cap with 2′-O-methylation that mimics host mRNAs preventing innate immune detection and allowing the virus to translate its RNA genome through the utilization of cap-dependent translation initiation effectors in a wide variety of host species. Our prior work established the requirement of the host mammalian target of rapamycin complex 1 (mTORC1 for optimal WNV growth and protein expression; yet, the roles of the downstream effectors of mTORC1 in WNV translation are unknown. In this study, we utilize gene deletion mutants in the ribosomal protein kinase called S6 kinase (S6K and eukaryotic translation initiation factor 4E-binding protein (4EBP pathways downstream of mTORC1 to define the role of mTOR-dependent translation initiation signals in WNV gene expression and growth. We now show that WNV growth and protein expression are dependent on mTORC1 mediated-regulation of the eukaryotic translation initiation factor 4E-binding protein/eukaryotic translation initiation factor 4E-binding protein (4EBP/eIF4E interaction and eukaryotic initiation factor 4F (eIF4F complex formation to support viral growth and viral protein expression. We also show that the canonical signals of mTORC1 activation including ribosomal protein s6 (rpS6 and S6K phosphorylation are not required for WNV growth in these same conditions. Our data suggest that the mTORC1/4EBP/eIF4E signaling axis is activated to support the translation of the WNV genome.

  8. 4EBP-Dependent Signaling Supports West Nile Virus Growth and Protein Expression.

    Science.gov (United States)

    Shives, Katherine D; Massey, Aaron R; May, Nicholas A; Morrison, Thomas E; Beckham, J David

    2016-10-18

    West Nile virus (WNV) is a (+) sense, single-stranded RNA virus in the Flavivirus genus. WNV RNA possesses an m7GpppNm 5' cap with 2'-O-methylation that mimics host mRNAs preventing innate immune detection and allowing the virus to translate its RNA genome through the utilization of cap-dependent translation initiation effectors in a wide variety of host species. Our prior work established the requirement of the host mammalian target of rapamycin complex 1 (mTORC1) for optimal WNV growth and protein expression; yet, the roles of the downstream effectors of mTORC1 in WNV translation are unknown. In this study, we utilize gene deletion mutants in the ribosomal protein kinase called S6 kinase (S6K) and eukaryotic translation initiation factor 4E-binding protein (4EBP) pathways downstream of mTORC1 to define the role of mTOR-dependent translation initiation signals in WNV gene expression and growth. We now show that WNV growth and protein expression are dependent on mTORC1 mediated-regulation of the eukaryotic translation initiation factor 4E-binding protein/eukaryotic translation initiation factor 4E-binding protein (4EBP/eIF4E) interaction and eukaryotic initiation factor 4F (eIF4F) complex formation to support viral growth and viral protein expression. We also show that the canonical signals of mTORC1 activation including ribosomal protein s6 (rpS6) and S6K phosphorylation are not required for WNV growth in these same conditions. Our data suggest that the mTORC1/4EBP/eIF4E signaling axis is activated to support the translation of the WNV genome.

  9. Construction and characterisation of a recombinant fowlpox virus that expresses the human papilloma virus L1 protein

    Directory of Open Access Journals (Sweden)

    Zanotto Carlo

    2011-11-01

    Full Text Available Abstract Background Human papilloma virus (HPV-16 is the most prevalent high-risk mucosal genotype. Virus-like-particle (VLP-based immunogens developed recently have proven to be successful as prophylactic HPV vaccines, but are still too expensive for developing countries. Although vaccinia viruses expressing the HPV-16 L1 protein (HPV-L1 have been studied, fowlpox-based recombinants represent efficient and safer vectors for immunocompromised hosts due to their ability to elicit a complete immune response and their natural host-range restriction to avian species. Methods A new fowlpox virus recombinant encoding HPV-L1 (FPL1 was engineered and evaluated for the correct expression of HPV-L1 in vitro, using RT-PCR, immunoprecipitation, Western blotting, electron microscopy, immunofluorescence, and real-time PCR assays. Results The FPL1 recombinant correctly expresses HPV-L1 in mammalian cells, which are non-permissive for the replication of this vector. Conclusion This FPL1 recombinant represents an appropriate immunogen for expression of HPV-L1 in human cells. The final aim is to develop a safe, immunogenic, and less expensive prophylactic vaccine against HPV.

  10. Intraventricular injection of myxoma virus results in transient expression of viral protein in mouse brain ependymal and subventricular cells.

    Science.gov (United States)

    France, Megan R; Thomas, Diana L; Liu, Jia; McFadden, Grant; MacNeill, Amy L; Roy, Edward J

    2011-01-01

    Oncolytic viruses that selectively infect and lyse cancer cells have potential as therapeutic agents. Myxoma virus, a poxvirus that is known to be pathogenic only in rabbits, has not been reported to infect normal tissues in humans or mice. We observed that when recombinant virus was injected directly into the lateral ventricle of the mouse brain, virally encoded red fluorescent protein was expressed in ependymal and subventricular cells. Cells were positive for nestin, a marker of neural stem cells. Rapamycin increased the number of cells expressing the virally encoded protein. However, protein expression was transient. Cells expressing the virally encoded protein did not undergo apoptosis and the ependymal lining remained intact. Myxoma virus appears to be safe when injected into the brain despite the transient expression of virally derived protein in a small population of periventricular cells.

  11. Avian adeno-associated virus-based expression of Newcastle disease virus hemagglutinin-neuraminidase protein for poultry vaccination.

    Science.gov (United States)

    Perozo, F; Villegas, P; Estevez, C; Alvarado, I R; Purvis, L B; Saume, E

    2008-06-01

    The avian adeno-associated virus (AAAV) is a replication-defective nonpathogenic virus member of the family Parvoviridae that has been proved to be useful as a viral vector for gene delivery. The use of AAAV for transgenic expression of Newcastle disease virus (NDV) hemagglutinin-neuraminidase (HN) protein and its ability to induce immunity in chickens were assessed. Proposed advantages of this system include no interference with maternal antibodies, diminished immune response against the vector, and the ability to accommodate large fragments of genetic information. In this work the generation of recombinant AAAV virions expressing the HN protein (rAAAV-HN) was demonstrated by electron microscopy, immunocytochemistry, and western blot analysis. Serological evidence of HN protein expression after in ovo or intramuscular inoculation of the recombinant virus in specific-pathogen-free chickens was obtained. Serum from rAAAV-HN-vaccinated birds showed a systemic immune response evidenced by NDV-specific enzyme-linked immunosorbent assay and hemagglutination inhibition testing. Positive virus neutralization in embryonated chicken eggs and indirect immunofluorescence detection of NDV infected cells by serum from rAAAV-HN vaccinated birds is also reported. A vaccine-challenge experiment in commercial broiler chickens using a Venezuelan virulent viscerotropic strain of NDV was performed. All unvaccinated controls died within 5 days postchallenge. Protection up to 80% was observed in birds vaccinated in ovo and revaccinated at 7 days of age with the rAAAV-HN. The results demonstrate the feasibility of developing and using an AAAV-based gene delivery system for poultry vaccination.

  12. Production of Polyclonal Antibody against Grapevine fanleaf virus Movement Protein Expressed in Escherichia coli

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    Davoud Koolivand

    2016-10-01

    Full Text Available The genomic region of Grapevine fanleaf virus (GFLV encoding the movement protein (MP was cloned into pET21a and transformed into Escherichia coli strain BL21 (DE3 to express the protein. Induction was made with a wide range of isopropyl-β-D-thiogalactopyranoside (IPTG concentrations (1, 1.5, and 2 mM each for duration of 4, 6, or 16 h. However, the highest expression level was achieved with 1 mM IPTG for 4 h. Identity of the expressed protein was confirmed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE followed by Western blotting. The expressed 41 kDa protein was purified under denaturing condition by affinity chromatography, reconfirmed by Western blotting and plate-trapped antigen enzyme-linked immunosorbent assay (PTA-ELISA before being used as a recombinant antigen to raise polyclonal antibodies in rabbits. Purified anti-GFLV MP immunoglobulines (IgGs and conjugated IgGs detected the expressed MP and GFLV virions in infected grapevines when used in PTA-ELISA, double antibody sandwich-ELISA, and Western blotting. This is the first report on the production of anti-GFLV MP polyclonal antibodies and application for the virus detection.

  13. Assembly of SIV virus-like particles containing envelope proteins using a baculovirus expression system.

    Science.gov (United States)

    Yamshchikov, G V; Ritter, G D; Vey, M; Compans, R W

    1995-12-01

    The requirements for SIV particle assembly and envelope incorporation were investigated using a baculovirus expression system. The Pr56gag precursor protein expressed under control of the polyhedrin promoter (pPolh) produced high levels of immature retrovirus-like particles (VLP) upon expression in Sf9 insect cells. To determine the optimal conditions for envelope protein (Env) incorporation into VLP, two recombinant baculoviruses expressing the SIV envelope protein under control of a very late pPolh or a hybrid late/very late capsid/polyhedrin (Pcap/polh) promoter and a recombinant expressing a truncated form of the SIV envelope protein (Envt) under the hybrid Pcap/polh promoter were compared. We have observed that utilization of the earlier hybrid promoter resulted in higher levels of Env expression on the cell surface and its incorporation into budding virus particles. We have also found that the Envt protein is transported to the cell surface of insect cells and incorporated into VLP more efficiently than full-length Env. In addition, we examined the effect of coexpression of the protease furin, which has been implicated in the proteolytic cleavage of the Env precursor gp160 in mammalian cells. Coexpression of furin in insect cells resulted in more efficient proteolytic cleavage into gp120 and gp41, and the cleaved proteins were incorporated into VLP.

  14. Proteomic analysis of differentially expressed proteins in hepatitis B virus-related hepatocellular carcinoma tissues

    OpenAIRE

    Li, Ning; Long, Yunzhu; Fan, Xuegong; Liu, Hongbo; Li, Cui; Chen, Lizhang; Wang, Zhiming

    2009-01-01

    Abstract Background Hepatocellular carcinoma (HCC), a major cause of cancer death in China, is preceded by chronic hepatitis and liver cirrhosis (LC). Although hepatitis B virus (HBV) has been regarded as a clear etiology of human hepatocarcinogenesis, the mechanism is still needs to be further clarified. In this study, we used a proteomic approach to identify the differential expression protein profiles between HCC and the adjacent non-tumorous liver tissues. Methods Eighteen cases of HBV-re...

  15. Expression of Separate Proteins in the Same Plant Leaves and Cells Using Two Independent Virus-Based Gene Vectors

    Directory of Open Access Journals (Sweden)

    Maria R. Mendoza

    2017-11-01

    Full Text Available Plant viral vectors enable the expression of proteins at high levels in a relatively short time. For many purposes (e.g., cell biological interaction studies it may be desirable to express more than one protein in a single cell but that is often not feasible when using a single virus vector. Such a co-expression strategy requires the simultaneous delivery by two compatible and non-competitive viruses that can co-exist to each express a separate protein. Here, we report on the use of two agro-launchable coat-protein gene substitution GFP-expressing virus vector systems based on Tomato bushy stunt virus (TBSV referred to as TG, and Tobacco mosaic virus (TMV annotated as TRBO-G. TG expressed GFP in Nicotiana benthamiana, tomato, lettuce and cowpea, whereas expression from TRBO-G was detected only in the first two species. Upon co-infiltration of the two vectors co-expression was monitored by: molecular detection of the two slightly differently sized GFPs, suppressor-complementation assays, and using TG in combination with TRBO-RFP. All the results revealed that in N. benthamiana and tomato the TBSV and TMV vectors accumulated and expressed proteins in the same plants, the same leaves, and in the same cells. Therefore, co-expression by these two vectors provides a platform for fast and high level expression of proteins to study their cell biology or other properties.

  16. Expression of Separate Proteins in the Same Plant Leaves and Cells Using Two Independent Virus-Based Gene Vectors.

    Science.gov (United States)

    Mendoza, Maria R; Payne, Alexandria N; Castillo, Sean; Crocker, Megan; Shaw, Brian D; Scholthof, Herman B

    2017-01-01

    Plant viral vectors enable the expression of proteins at high levels in a relatively short time. For many purposes (e.g., cell biological interaction studies) it may be desirable to express more than one protein in a single cell but that is often not feasible when using a single virus vector. Such a co-expression strategy requires the simultaneous delivery by two compatible and non-competitive viruses that can co-exist to each express a separate protein. Here, we report on the use of two agro-launchable coat-protein gene substitution GFP-expressing virus vector systems based on Tomato bushy stunt virus (TBSV) referred to as TG, and Tobacco mosaic virus (TMV) annotated as TRBO-G. TG expressed GFP in Nicotiana benthamiana, tomato, lettuce and cowpea, whereas expression from TRBO-G was detected only in the first two species. Upon co-infiltration of the two vectors co-expression was monitored by: molecular detection of the two slightly differently sized GFPs, suppressor-complementation assays, and using TG in combination with TRBO-RFP. All the results revealed that in N. benthamiana and tomato the TBSV and TMV vectors accumulated and expressed proteins in the same plants, the same leaves, and in the same cells. Therefore, co-expression by these two vectors provides a platform for fast and high level expression of proteins to study their cell biology or other properties.

  17. Differential cellular protein expression in continuous porcine alveolar macrophages regulated by the porcine reproductive and respiratory syndrome virus nucleocapsid protein.

    Science.gov (United States)

    Sagong, Mingeun; Lee, Changhee

    2010-07-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) is a leading cause of significant economic losses in the pig industry worldwide. PRRSV infects preferentially porcine alveolar macrophages (PAMs) and subsequently utilizes the host cell biosynthetic machinery for its own replication. To date, a number of studies have been conducted to investigate compensatory changes of cellular gene expression of PAMs upon PRRSV infection. However, very little information exists about differential cellular protein expression of the natural target cells regulated by each viral protein. This study was therefore designed to examine the dynamics of host protein expression of continuous PAM cells by the PRRSV nucleocapsid (N) protein that is the most abundant and multifunctional viral component. We first established sublines of PAM cells to stably express the PRRSV N protein and assessed alterations in cellular protein productions of N-expressing PAM (PAM-pCD163-N) cells at different time courses by the use of proteomic analysis. A total of 23 protein spots were initially found to be differentially expressed in PAM-pCD163-N cells compared with normal PAM cells by high-resolution two-dimensional gel electrophoresis (2DE). Of these spots, 15 protein spots with statistically significant alteration, including 4 up-regulated and 11 down-regulated protein spots, were picked out for subsequent protein identification by peptide mass fingerprinting after matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS). The altered cellular proteins identified in this study were classified into the functions involved in a variety of cellular processes such as cell division, metabolism, inflammation response, stress response, ubiquitin-proteasome pathway, protein folding and synthesis, and transportation. Notably, heat shock 27kDa protein (HSP27) was found to be up-regulated in PAM-pCD163-N cells. The proteomics data will provide insights into the specific

  18. Expression and partial characterisation of rabbit haemorrhagic disease virus non-structural proteins.

    Science.gov (United States)

    Urakova, Nadya; Frese, Michael; Hall, Robyn N; Liu, June; Matthaei, Markus; Strive, Tanja

    2015-10-01

    The intracellular replication and molecular virulence mechanisms of Rabbit haemorrhagic disease virus (RHDV) are poorly understood, mainly due to the lack of an effective cell culture system for this virus. To increase our understanding of RHDV molecular biology, the subcellular localisation of recombinant non-structural RHDV proteins was investigated in transiently transfected rabbit kidney (RK-13) cells. We provide evidence for oligomerisation of p23, and an ability of the viral protease to cleave the p16:p23 junction in trans, outside the context of the nascent polyprotein chain. Notably, expression of the viral polymerase alone and in the context of the entire RHDV polyprotein resulted in a redistribution of the Golgi network. This suggests that, similar to other positive-strand RNA viruses, RHDV may recruit membranes of the secretory pathway during replication, and that the viral polymerase may play a critical role during this process. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Recombinant capripoxviruses expressing proteins of bluetongue virus: evaluation of immune responses and protection in small ruminants.

    Science.gov (United States)

    Perrin, Aurélie; Albina, Emmanuel; Bréard, Emmanuel; Sailleau, Corinne; Promé, Sylvie; Grillet, Colette; Kwiatek, Olivier; Russo, Pierre; Thiéry, Richard; Zientara, Stephan; Cêtre-Sossah, Catherine

    2007-09-17

    The development of recombinant capripoxviruses for protective immunization of ruminants against bluetongue virus (BTV) infection is described. Sheep (n=11) and goats (n=4) were immunized with BTV recombinant capripoxviruses (BTV-Cpox) individually expressing four different genes encoding two capsid proteins (VP2 and VP7) and two non-structural proteins (NS1, NS3) of BTV serotype 2 (BTV-2). Seroconversion was observed against NS3, VP7 and VP2 in both species and a lymphoproliferation specific to BTV antigens was also demonstrated in goats. Finally, partial protection of sheep challenged 3 weeks after BTV-Cpox administration with a virulent strain of BTV-2, was observed.

  20. Expression, characterisation and antigenicity of a truncated Hendra virus attachment protein expressed in the protozoan host Leishmania tarentolae.

    Science.gov (United States)

    Fischer, Kerstin; dos Reis, Vinicius Pinho; Finke, Stefan; Sauerhering, Lucie; Stroh, Eileen; Karger, Axel; Maisner, Andrea; Groschup, Martin H; Diederich, Sandra; Balkema-Buschmann, Anne

    2016-02-01

    Hendra virus (HeV) is an emerging zoonotic paramyxovirus within the genus Henipavirus that has caused severe morbidity and mortality in humans and horses in Australia since 1994. HeV infection of host cells is mediated by the membrane bound attachment (G) and fusion (F) glycoproteins, that are essential for receptor binding and fusion of viral and cellular membranes. The eukaryotic unicellular parasite Leishmania tarentolae has recently been established as a powerful tool to express recombinant proteins with mammalian-like glycosylation patterns, but only few viral proteins have been expressed in this system so far. Here, we describe the purification of a truncated, Strep-tag labelled and soluble version of the HeV attachment protein (sHeV G) expressed in stably transfected L. tarentolae cells. After Strep-tag purification the identity of sHeV G was confirmed by immunoblotting and mass spectrometry. The functional binding of sHeV G to the HeV cell entry receptor ephrin-B2 was confirmed in several binding assays. Generated polyclonal rabbit antiserum against sHeV G reacted with both HeV and Nipah virus (NiV) G proteins in immunofluorescence assay and efficiently neutralised NiV infection, thus further supporting the preserved antigenicity of the purified protein. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  1. Expression and characterization of Escherichia coli derived hepatitis C virus ARFP/F protein.

    Science.gov (United States)

    Baghbani-arani, F; Roohvand, F; Aghasadeghi, M R; Eidi, A; Amini, S; Motevalli, F; Sadat, S M; Memarnejadian, A; Khalili, G

    2012-01-01

    Genome of the hepatitis C virus (HCV) contains a long open reading frame encoding a polyprotein that is cleaved into 10 proteins. Recently, a novel, so called "ARFP/F", or "core+1", protein, which is expressed through a ribosomal frame shift within the capsid-coding sequence, has been described. Herein, to produce and characterize a recombinant form of this protein, the DNA sequence corresponding to the ARFP/F protein (amino acid 11-161) was amplified using a frame-shifted forward primer exploiting the capsid sequence of the 1b-subtype as a template. The amplicon was cloned into the pET-24a vector and expressed in different Escherichia coli strains. The expressed protein (mostly as insoluble inclusion bodies) was purified under denaturing conditions on a nickel-nitrilotriacetic acid (Ni-NTA) affinity column in a single step with a yield of 5 mg/L of culture media. After refolding steps, characterization of expressed ARFP/F was performed by SDS-PAGE and Western blot assay using specific antibodies. Antigenic properties of the protein were verified by ELISA using HCV-infected human sera and by its ability for a strong and specific interaction with sera of mice immunized with the peptide encoding a dominant ARFP/F B-cell epitope. The antigenicity plot revealed 3 major antigenic domains in the first half of the ARFP/F sequence. Immunization of BALB/c mice with the ARFP/F protein elicited high titers of IgG indicating the relevance of produced protein for induction of a humoral response. In conclusion, possibility of ARFP/F expression with a high yield and immunogenic potency of this protein in a mouse model have been demonstrated.

  2. Induction of feline immunodeficiency virus specific antibodies in cats with an attenuated Salmonella strain expressing the Gag protein.

    NARCIS (Netherlands)

    E.J. Tijhaar (Edwin); C.H.J. Siebelink (Kees); J.A. Karlas (Jos); M.C. Burger; F.R. Mooi (Frits); A.D.M.E. Osterhaus (Albert)

    1997-01-01

    textabstractSalmonella typhimurium aroA strains (SL3261), expressing high levels of the Gag protein of feline immunodeficiency virus (FIV) fused with maltose binding protein (SL3261-MFG), were constructed using an invertible promoter system that allows the stable expression of heterologous antigens

  3. Stable human lymphoblastoid cell lines constitutively expressing hepatitis C virus proteins.

    Science.gov (United States)

    Wölk, Benno; Gremion, Christel; Ivashkina, Natalia; Engler, Olivier B; Grabscheid, Benno; Bieck, Elke; Blum, Hubert E; Cerny, Andreas; Moradpour, Darius

    2005-06-01

    The cellular immune response plays a central role in virus clearance and pathogenesis of liver disease in hepatitis C. The study of hepatitis C virus (HCV)-specific immune responses is limited by currently available cell-culture systems. Here, the establishment and characterization of stable human HLA-A2-positive B-lymphoblastoid x T hybrid cell lines constitutively expressing either the NS3-4A complex or the entire HCV polyprotein are reported. These cell lines, termed T1/NS3-4A and T1/HCVcon, respectively, were maintained in continuous culture for more than 1 year with stable characteristics. HCV structural and non-structural proteins were processed accurately, indicating that the cellular and viral proteolytic machineries are functional in these cell lines. Viral proteins were found in the cytoplasm in dot-like structures when expressed in the context of the HCV polyprotein or in a perinuclear fringe when the NS3-4A complex was expressed alone. T1/NS3-4A and T1/HCVcon cells were lysed efficiently by HCV-specific cytotoxic T lymphocytes from patients with hepatitis C and from human HLA-A2.1 transgenic mice immunized with a liposomal HCV vaccine, indicating that viral proteins are processed endogenously and presented efficiently via the major histocompatibility complex class I pathway. In conclusion, these cell lines represent a unique tool to study the cellular immune response, as well as to evaluate novel vaccine and immunotherapeutic strategies against HCV.

  4. Proteomic analysis of differentially expressed proteins in hepatitis B virus-related hepatocellular carcinoma tissues

    Directory of Open Access Journals (Sweden)

    Li Cui

    2009-08-01

    Full Text Available Abstract Background Hepatocellular carcinoma (HCC, a major cause of cancer death in China, is preceded by chronic hepatitis and liver cirrhosis (LC. Although hepatitis B virus (HBV has been regarded as a clear etiology of human hepatocarcinogenesis, the mechanism is still needs to be further clarified. In this study, we used a proteomic approach to identify the differential expression protein profiles between HCC and the adjacent non-tumorous liver tissues. Methods Eighteen cases of HBV-related HCC including 12 cases of LC-developed HCC and 6 cases of chronic hepatitis B (CHB-developed HCC were analyzed by two-dimensional electrophoresis (2-DE combined with matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS, and the results were compared to those of paired adjacent non-tumorous liver tissues. Results A total of 17 differentially expressed proteins with diverse biological functions were identified. Among these, 10 proteins were up-regulated, whereas the other 7 proteins were down-regulated in cancerous tissues. Two proteins, c-Jun N-terminal kinase 2 and ADP/ATP carrier protein were found to be up-regulated only in CHB-developed HCC tissues. Insulin-like growth factor binding protein 2 and Rho-GTPase-activating protein 4 were down-regulated in LC-developed and CHB-developed HCC tissues, respectively. Although 11 out of these 17 proteins have been already described by previous studies, or are already known to be involved in hepatocarcinogenesis, this study revealed 6 new proteins differentially expressed in HBV-related HCC. Conclusion These findings elucidate that there are common features between CHB-developed HCC and LC-developed HCC. The identified proteins are valuable for studying the hepatocarcinogenesis, and may be potential diagnostic markers or therapeutic targets for HBV-related HCC.

  5. Proteomic analysis of differentially expressed proteins in hepatitis B virus-related hepatocellular carcinoma tissues.

    Science.gov (United States)

    Li, Ning; Long, Yunzhu; Fan, Xuegong; Liu, Hongbo; Li, Cui; Chen, Lizhang; Wang, Zhiming

    2009-08-28

    Hepatocellular carcinoma (HCC), a major cause of cancer death in China, is preceded by chronic hepatitis and liver cirrhosis (LC). Although hepatitis B virus (HBV) has been regarded as a clear etiology of human hepatocarcinogenesis, the mechanism is still needs to be further clarified. In this study, we used a proteomic approach to identify the differential expression protein profiles between HCC and the adjacent non-tumorous liver tissues. Eighteen cases of HBV-related HCC including 12 cases of LC-developed HCC and 6 cases of chronic hepatitis B (CHB)-developed HCC were analyzed by two-dimensional electrophoresis (2-DE) combined with matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS), and the results were compared to those of paired adjacent non-tumorous liver tissues. A total of 17 differentially expressed proteins with diverse biological functions were identified. Among these, 10 proteins were up-regulated, whereas the other 7 proteins were down-regulated in cancerous tissues. Two proteins, c-Jun N-terminal kinase 2 and ADP/ATP carrier protein were found to be up-regulated only in CHB-developed HCC tissues. Insulin-like growth factor binding protein 2 and Rho-GTPase-activating protein 4 were down-regulated in LC-developed and CHB-developed HCC tissues, respectively. Although 11 out of these 17 proteins have been already described by previous studies, or are already known to be involved in hepatocarcinogenesis, this study revealed 6 new proteins differentially expressed in HBV-related HCC. These findings elucidate that there are common features between CHB-developed HCC and LC-developed HCC. The identified proteins are valuable for studying the hepatocarcinogenesis, and may be potential diagnostic markers or therapeutic targets for HBV-related HCC.

  6. Enhanced-Transient Expression of Hepatitis C Virus Core Protein in Nicotiana tabacum, a Protein With Potential Clinical Applications.

    Science.gov (United States)

    Mohammadzadeh, Sara; Khabiri, Alireza; Roohvand, Farzin; Memarnejadian, Arash; Salmanian, Ali Hatef; Ajdary, Soheila; Ehsani, Parastoo

    2014-11-01

    Hepatitis C virus (HCV) is major cause of liver cirrhosis in humans. HCV capsid (core) protein (HCVcp) is a highly demanded antigen for various diagnostic, immunization and pathogenesis studies. Plants are considered as an expression system for producing safe and inexpensive biopharmaceutical proteins. Although invention of transgenic (stable) tobacco plants expressing HCVcp with proper antigenic properties was recently reported, no data for "transient-expression" that is currently the method of choice for rapid, simple and lower-priced protein expression in plants is available for HCVcp. The purpose of this study was to design a highly codon-optimized HCVcp gene for construction of an efficient transient-plant expression system for production of HCVcp with proper antigenic properties in a regional tobacco plant (Iranian Jafarabadi-cultivar) by evaluation of different classes of vectors and suppression of gene-silencing in tobacco. A codon-optimized gene encoding the Kozak sequence, 6xHis-tag, HCVcp (1-122) and KDEL peptide in tandem (from N- to C-terminal) was designed and inserted into potato virus-X (PVX) and classic pBI121 binary vectors in separate cloning reactions. The resulted recombinant plasmids were transferred into Agrobacterium tumefaciens and vacuum infiltrated into tobacco leaves. The effect of gene silencing suppressor P19 protein derived from tomato bushy stunt virus on the expression yield of HCVcp by each construct was also evaluated by co-infiltration in separate groups. The expressed HCVcp was evaluated by dot and western blotting and ELISA assays. The codon-optimized gene had an increased adaptation index value (from 0.65 to 0.85) and reduced GC content (from 62.62 to 51.05) in tobacco and removed the possible deleterious effect of "GGTAAG" splice site in native HCVcp. Blotting assays via specific antibodies confirmed the expression of the 15 kDa HCVcp. The expression level of HCVcp was enhanced by 4-5 times in P19 co-agroinfiltrated plants

  7. Expression and functional characterization of bluetongue virus VP2 protein: role in cell entry.

    Science.gov (United States)

    Hassan, S S; Roy, P

    1999-12-01

    Segment 2 of bluetongue virus (BTV) serotype 10, which encodes the outer capsid protein VP2, was tagged with the S-peptide fragment of RNase A and expressed by a recombinant baculovirus. The recombinant protein was subsequently purified to homogeneity by virtue of the S tag, and the oligomeric nature of the purified protein was determined. The data obtained indicated that the majority of the protein forms a dimer and, to a lesser extent, some trimer. The recombinant protein was used to determine various biological functions of VP2. The purified VP2 was shown to have virus hemagglutinin activity and was antigenically indistinguishable from the VP2 of the virion. Whether VP2 is responsible for BTV entry into permissive cells was subsequently assessed by cell surface attachment and internalization studies with an immunofluorescence assay system. The results demonstrated that VP2 alone is responsible for virus entry into mammalian cells. By competition assay, it appeared that both VP2 and the BTV virion attached to the same cell surface molecule(s). The purified VP2 also had a strong affinity for binding to glycophorin A, a sialoglycoprotein component of erythrocytes, indicating that VP2 may be responsible for BTV transmission by the Culicoides vector to vertebrate hosts during blood feeding. Further, by various enzymatic treatments of BTV-permissive L929 cells, preliminary data have been obtained which indicated that the BTV receptor molecule(s) is likely to be a glycoprotein and that either the protein moiety of the glycoprotein or a second protein molecule could also serve as a coreceptor for BTV infection.

  8. Constitutively Expressed IFITM3 Protein in Human Endothelial Cells Poses an Early Infection Block to Human Influenza Viruses.

    Science.gov (United States)

    Sun, Xiangjie; Zeng, Hui; Kumar, Amrita; Belser, Jessica A; Maines, Taronna R; Tumpey, Terrence M

    2016-12-15

    A role for pulmonary endothelial cells in the orchestration of cytokine production and leukocyte recruitment during influenza virus infection, leading to severe lung damage, has been recently identified. As the mechanistic pathway for this ability is not fully known, we extended previous studies on influenza virus tropism in cultured human pulmonary endothelial cells. We found that a subset of avian influenza viruses, including potentially pandemic H5N1, H7N9, and H9N2 viruses, could infect human pulmonary endothelial cells (HULEC) with high efficiency compared to human H1N1 or H3N2 viruses. In HULEC, human influenza viruses were capable of binding to host cellular receptors, becoming internalized and initiating hemifusion but failing to uncoat the viral nucleocapsid and to replicate in host nuclei. Unlike numerous cell types, including epithelial cells, we found that pulmonary endothelial cells constitutively express a high level of the restriction protein IFITM3 in endosomal compartments. IFITM3 knockdown by small interfering RNA (siRNA) could partially rescue H1N1 virus infection in HULEC, suggesting IFITM3 proteins were involved in blocking human influenza virus infection in endothelial cells. In contrast, selected avian influenza viruses were able to escape IFITM3 restriction in endothelial cells, possibly by fusing in early endosomes at higher pH or by other, unknown mechanisms. Collectively, our study demonstrates that the human pulmonary endothelium possesses intrinsic immunity to human influenza viruses, in part due to the constitutive expression of IFITM3 proteins. Notably, certain avian influenza viruses have evolved to escape this restriction, possibly contributing to virus-induced pneumonia and severe lung disease in humans. Avian influenza viruses, including H5N1 and H7N9, have been associated with severe respiratory disease and fatal outcomes in humans. Although acute respiratory distress syndrome (ARDS) and progressive pulmonary endothelial damage

  9. Tumor Suppressor p53 Stimulates the Expression of Epstein-Barr Virus Latent Membrane Protein 1.

    Science.gov (United States)

    Wang, Qianli; Lingel, Amy; Geiser, Vicki; Kwapnoski, Zachary; Zhang, Luwen

    2017-10-15

    Epstein-Barr virus (EBV) is associated with multiple human malignancies. EBV latent membrane protein 1 (LMP1) is required for the efficient transformation of primary B lymphocytes in vitro and possibly in vivo The tumor suppressor p53 plays a seminal role in cancer development. In some EBV-associated cancers, p53 tends to be wild type and overly expressed; however, the effects of p53 on LMP1 expression is not clear. We find LMP1 expression to be associated with p53 expression in EBV-transformed cells under physiological and DNA damaging conditions. DNA damage stimulates LMP1 expression, and p53 is required for the stimulation. Ectopic p53 stimulates endogenous LMP1 expression. Moreover, endogenous LMP1 blocks DNA damage-mediated apoptosis. Regarding the mechanism of p53-mediated LMP1 expression, we find that interferon regulatory factor 5 (IRF5), a direct target of p53, is associated with both p53 and LMP1. IRF5 binds to and activates a LMP1 promoter reporter construct. Ectopic IRF5 increases the expression of LMP1, while knockdown of IRF5 leads to reduction of LMP1. Furthermore, LMP1 blocks IRF5-mediated apoptosis in EBV-infected cells. All of the data suggest that cellular p53 stimulates viral LMP1 expression, and IRF5 may be one of the factors for p53-mediated LMP1 stimulation. LMP1 may subsequently block DNA damage- and IRF5-mediated apoptosis for the benefits of EBV. The mutual regulation between p53 and LMP1 may play an important role in EBV infection and latency and its related cancers.IMPORTANCE The tumor suppressor p53 is a critical cellular protein in response to various stresses and dictates cells for various responses, including apoptosis. This work suggests that an Epstein-Bar virus (EBV) principal viral oncogene is activated by cellular p53. The viral oncogene blocks p53-mediated adverse effects during viral infection and transformation. Therefore, the induction of the viral oncogene by p53 provides a means for the virus to cope with infection and DNA

  10. Visualizing viral dissemination in the mouse nervous system, using a green fluorescent protein-expressing Borna disease virus vector.

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    Ackermann, Andreas; Guelzow, Timo; Staeheli, Peter; Schneider, Urs; Heimrich, Bernd

    2010-05-01

    Borna disease virus (BDV) frequently persists in the brain of infected animals. To analyze viral dissemination in the mouse nervous system, we generated a mouse-adapted virus that expresses green fluorescent protein (GFP). This viral vector supported GFP expression for up to 150 days and possessed an extraordinary staining capacity, visualizing complete dendritic arbors as well as individual axonal fibers of infected neurons. GFP-positive cells were first detected in cortical areas from where the virus disseminated through the entire central nervous system (CNS). Late in infection, GFP expression was found in the sciatic nerve, demonstrating viral spread from the central to the peripheral nervous system.

  11. Construction and immune efficacy of recombinant pseudorabies virus expressing PrM-E proteins of Japanese encephalitis virus genotype І.

    Science.gov (United States)

    Qian, Ping; Zhi, Xianwei; Wang, Bo; Zhang, Huawei; Chen, Huanchun; Li, Xiangmin

    2015-12-10

    Japanese encephalitis (JE) is an arboviral disease with high case fatality rates and neurologic or psychiatric sequelae among survivors in Asia, western Pacific countries and northern Australia. Japanese encephalitis virus (JEV) is the cause of JE and the emergence of genotype І (GI) JEV has displaced genotype III (GIII) as the dominant strains circulating in some Asian regions. The currently available JE vaccines are safe and effective in preventing this disease, but they are developed based on the GIII JEV strains. The recombinant virus PRV TK(-)/gE(-)/PrM-E(+) which expressed the premembrane (prM) and envelope (E) proteins of JEV SX09S-01 strain (genotype I, GI) was constructed by homologous recombination between the genome of PRV TK(-)/gE(-)/LacZ(+) digested with EcoRI and plasmid pIE-CAG-PrM-E-BGH. Expression of JEV PrM and E proteins was analyzed by Western blot analysis. Immune efficacy of PRV TK(-)/gE(-)/PrM-E(+) was further evaluated in mouse model. A recombinant pseudorabies virus (PRV TK(-)/gE(-)/PrM-E(+)) was successfully constructed. Mice experiments showed that PRV TK(-)/gE(-)/PrM-E(+) could induce a high level of ELISA antibodies against PRV and JEV, as well as high titer of PRV neutralizing antibodies. After challenge with 1 × 10(7) PFU virulent JEV SX09S-01 strain, the time of death was delayed and the survival rate was improved in PRV TK(-)/gE(-)/PrM-E(+) vaccinated mice. PRV TK(-)/gE(-)/PrM-E(+) is a potential vaccine candidate against PRV and JEV GI infection in the future.

  12. Method for rapid optimization of recombinant GPCR protein expression and stability using virus-like particles.

    Science.gov (United States)

    Ho, Thao T; Nguyen, Jasmine T; Liu, Juping; Stanczak, Pawel; Thompson, Aaron A; Yan, Yingzhuo G; Chen, Jasmine; Allerston, Charles K; Dillard, Charles L; Xu, Hao; Shoger, Nicholas J; Cameron, Jill S; Massari, Mark E; Aertgeerts, Kathleen

    2017-05-01

    Recent innovative approaches to stabilize and crystallize GPCRs have resulted in an unprecedented breakthrough in GPCR crystal structures as well as application of the purified receptor protein in biophysical and biochemical ligand binding assays. However, the protein optimization process to enable these technologies is lengthy and requires iterative overexpression, solubilization, purification and functional analysis of tens to hundreds of protein variants. Here, we report a new and versatile method to screen in parallel hundreds of GPCR variants in HEK293 produced virus-like particles (VLPs) for protein yield, stability, functionality and ligand binding. This approach reduces the time and resources during GPCR construct optimization by eliminating lengthy protein solubilization and purification steps and by its adaptability to many binding assay formats (label or label-free detection). We exemplified the robustness of our VLP method by screening 210 GALR3-VLP variants in a radiometric agonist-based binding assay and a subset of 88 variants in a label-free antagonist-based assay. The resulting GALR3 agonist or antagonist stabilizing variants were then further used for recombinant protein expression in transfected insect cells. The final purified protein variants were successfully immobilized on a biosensor chip and used in a surface plasmon resonance binding assay. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Loss of P16 Protein Expression and Its Association with Epstein-Barr Virus LMP-1 Expression in Hodgkin's Lymphoma.

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    Irshaid, Fawzi; Tarawneh, Khaled; Alshdefat, Aisha; Dilmi, Fatiha; Jaran, Adnan; Al-Hadithi, Raji; Al-Khatib, Ahad

    2013-01-01

    Expression of Epstein-Barr virus Latent Member Protein-1 (EBV LMP-1) and loss of P16 protein expression are documented in lymphoma, indicating a relationship between them, but this relationship is not clear and sometimes contradictory. Thus, this study was conducted to examine the relationship between the loss of P16 and EBV LMP-1 expression in Jordanian patients diagnosed with lymphoma. Sections were made from archival formalin-fixed and paraffin-embedded blocks from 55 patients diagnosed with lymphoma. P16 expression and LMP-1 expression were detected by immunohistochemistry using monoclonal antibodies. In Hodgkin's Lymphoma (HL), the loss of P16 was higher in LMP-1 positive cases (61%) than LMP-1 negative cases (25%; P = 0.072). Conversely, in Non-Hodgkin's Lymphoma (NHL), none of LMP-1 positive samples showed loss of P16. Furthermore, among LMP-1 HL positive cases, the loss of P16 was more frequent in male (75%) than female (33%). Also, there was a significantly higher proportion of LMP-1 positive cases showing loss of P16 in HL (11:18), compared to those in NHL (0:8, P < 0.001), confirming a difference between HL and NHL, concerning the LMP-1/P16 relationship. A trend for an association between loss of P16 and LMP-1 expression was observed in HL but not NHL patients. These findings suggest that there are molecular and clinical differences in the pathogenesis and development of different subtypes of lymphoma.

  14. Recombinant expression and purification of 'virus-like' bacterial encapsulin protein cages

    NARCIS (Netherlands)

    Rurup, W.F.; Cornelissen, Jeroen Johannes Lambertus Maria; Koay, M.S.T.; Orner, Brendan P.

    2014-01-01

    Ultracentrifugation, particularly the use of sucrose or cesium chloride density gradients, is a highly reliable and efficient technique for the purification of virus-like particles and protein cages. Since virus-like particles and protein cages have a unique size compared to cellular macromolecules

  15. Recombinant expression and purification of 'virus-like' bacterial encapsulin protein cages

    NARCIS (Netherlands)

    Rurup, W.F.; Cornelissen, Jeroen Johannes Lambertus Maria; Koay, M.S.T.; Orner, Brendan P.

    2015-01-01

    Ultracentrifugation, particularly the use of sucrose or cesium chloride density gradients, is a highly reliable and efficient technique for the purification of virus-like particles and protein cages. Since virus-like particles and protein cages have a unique size compared to cellular macromolecules

  16. Immunodiagnosis of Citrus leprosis virus C using a polyclonal antibody to an expressed putative coat protein.

    Science.gov (United States)

    Choudhary, Nandlal; Roy, Avijit; Guillermo, Leon M; Picton, D D; Wei, G; Nakhla, M K; Levy, L; Brlansky, R H

    2013-11-01

    Citrus leprosis virus C (CiLV-C), a causal agent for citrus leprosis disease, is present in South and Central America and is a threat for introduction into the U.S. citrus industry. A specific, inexpensive and reliable antibody based detection system is needed for the rapid identification of CiLV-C. The CiLV-C is very labile and has not been purified in sufficient amount for antibody production. The p29 gene of CiLV-C genome that codes for the putative coat protein (PCP) was codon optimized for expression in Escherichia coli and synthesized in vitro. The optimized gene was sub-cloned into the bacterial expression vector pDEST17 and transferred into E. coli BL21AI competent cells. The expression of PCP containing N-terminal His-tag was optimized by induction with l-arabinose. Induced cells were disrupted by sonication and expressed PCP was purified by affinity chromatography using Ni-NTA agarose. The purified expressed PCP was then used as an immunogen for injections into rabbits to produce polyclonal antibody (PAb). The PAb specific to the expressed PCP was identified using Western blotting. The antibody was successfully used to detect CiLV-C in the symptomatic CiLV-C infected tissues using double antibody sandwich-enzyme-linked-immunosorbent (DAS-ELISA), indirect ELISA and dot-blot immunoassay (DBIA) formats. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Capsid protein expression and adeno-associated virus like particles assembly in Saccharomyces cerevisiae

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    Backovic Ana

    2012-09-01

    Full Text Available Abstract Background The budding yeast Saccharomyces cerevisiae supports replication of many different RNA or DNA viruses (e.g. Tombusviruses or Papillomaviruses and has provided means for up-scalable, cost- and time-effective production of various virus-like particles (e.g. Human Parvovirus B19 or Rotavirus. We have recently demonstrated that S. cerevisiae can form single stranded DNA AAV2 genomes starting from a circular plasmid. In this work, we have investigated the possibility to assemble AAV capsids in yeast. Results To do this, at least two out of three AAV structural proteins, VP1 and VP3, have to be simultaneously expressed in yeast cells and their intracellular stoichiometry has to resemble the one found in the particles derived from mammalian or insect cells. This was achieved by stable co-transformation of yeast cells with two plasmids, one expressing VP3 from its natural p40 promoter and the other one primarily expressing VP1 from a modified AAV2 Cap gene under the control of the inducible yeast promoter Gal1. Among various induction strategies we tested, the best one to yield the appropriate VP1:VP3 ratio was 4.5 hour induction in the medium containing 0.5% glucose and 5% galactose. Following such induction, AAV virus like particles (VLPs were isolated from yeast by two step ultracentrifugation procedure. The transmission electron microscopy analysis revealed that their morphology is similar to the empty capsids produced in human cells. Conclusions Taken together, the results show for the first time that yeast can be used to assemble AAV capsid and, therefore, as a genetic system to identify novel cellular factors involved in AAV biology.

  18. Solubility as a limiting factor for expression of hepatitis A virus proteins in insect cell-baculovirus system

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    Haroldo Cid da Silva Junior

    2016-08-01

    Full Text Available The use of recombinant proteins may represent an alternative model to inactivated vaccines against hepatitis A virus (HAV. The present study aimed to express the VP1 protein of HAV in baculovirus expression vector system (BEVS. The VP1 was expressed intracellularly with molecular mass of 35 kDa. The VP1 was detected both in the soluble fraction and in the insoluble fraction of the lysate. The extracellular expression of VP1 was also attempted, but the protein remained inside the cell. To verify if hydrophobic characteristics would also be present in the HAV structural polyprotein, the expression of P1-2A protein was evaluated. The P1-2A polyprotein remained insoluble in the cellular extract, even in the early infection stages. These results suggest that HAV structural proteins are prone to form insoluble aggregates. The low solubility represents a drawback for production of large amounts of HAV proteins in BEVS.

  19. Bacterial-based systems for expression and purification of recombinant Lassa virus proteins of immunological relevance

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    Cashman Kathleen A

    2008-06-01

    Full Text Available Abstract Background There is a significant requirement for the development and acquisition of reagents that will facilitate effective diagnosis, treatment, and prevention of Lassa fever. In this regard, recombinant Lassa virus (LASV proteins may serve as valuable tools in diverse antiviral applications. Bacterial-based systems were engineered for expression and purification of recombinant LASV nucleoprotein (NP, glycoprotein 1 (GP1, and glycoprotein 2 (GP2. Results Full-length NP and the ectodomains of GP1 and GP2 were generated as maltose-binding protein (MBP fusions in the Rosetta strains of Escherichia coli (E. coli using pMAL-c2x vectors. Average fusion protein yields per liter of culture for MBP-NP, MBP-GP1, and MBP-GP2 were 10 mg, 9 mg, and 9 mg, respectively. Each protein was captured from cell lysates using amylose resin, cleaved with Factor Xa, and purified using size-exclusion chromatography (SEC. Fermentation cultures resulted in average yields per liter of 1.6 mg, 1.5 mg, and 0.7 mg of purified NP, GP1 and GP2, respectively. LASV-specific antibodies in human convalescent sera specifically detected each of the purified recombinant LASV proteins, highlighting their utility in diagnostic applications. In addition, mouse hyperimmune ascitic fluids (MHAF against a panel of Old and New World arenaviruses demonstrated selective cross reactivity with LASV proteins in Western blot and enzyme-linked immunosorbent assay (ELISA. Conclusion These results demonstrate the potential for developing broadly reactive immunological assays that employ all three arenaviral proteins individually and in combination.

  20. Differential expression of the Ebola virus GP(1,2) protein and its fragments in E. coli.

    Science.gov (United States)

    Das, Dipankar; Jacobs, Fred; Feldmann, Heinz; Jones, Steven M; Suresh, Mavanur R

    2007-07-01

    Bacterial expression platforms are frequently used for the expression and production of different recombinant proteins. The full length Ebola virus (EBOV) GP(1,2) gene and subfragments of the GP(1) gene were cloned in a bacterial expression vector as a C-terminal His(6) fusion protein. Surprisingly, the full length EBOV GP(1,2) gene could not be expressed in Escherichia coli. The subfragments of GP(1) were only expressed in small amounts with the exception of one small fragment (subfragment D) which was expressed at very high levels as inclusion bodies. This was seen even in the in vitro translation system with no expression of full length GP(1,2), GP(1) subfragments A and C and low level expression of subfragment B. Only the subfragment D showed high level of expression. In E. coli (Top10), the recombinant GP(1) subfragment D protein was expressed exclusively as an insoluble approximately 25 kDa His(6) fusion protein, which is the expected size for a non-glycosylated recombinant protein. The IMAC purified and refolded non-glycosylated protein was used to immunize mice for the development of monoclonal anti-EBOV antibodies which successfully yielded several monoclonal antibodies with different specificities. The monoclonal and polyclonal antiserum derived from the animals immunized with this recombinant GP(1) subfragment D protein was found to specifically recognize the full length glycosylated EBOV GP(1,2) protein expressed in mammalian 293T cells, thus, demonstrating the immunogenicity of the recombinant subfragment.

  1. Varicella-Zoster Virus glycoprotein expression differentially induces the unfolded protein response in infected cells.

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    John Earl Carpenter

    2014-07-01

    Full Text Available Varicella-zoster virus (VZV is a human herpesvirus that spreads to children as varicella or chicken pox. The virus then establishes latency in the nervous system and re-emerges, typically decades later, as zoster or shingles. We have reported previously that VZV induces autophagy in infected cells as well as exhibiting evidence of the Unfolded Protein Response (UPR: XBP1 splicing, a greatly expanded Endoplasmic Reticulum (ER and CHOP expression. Herein we report the results of a UPR specific PCR array that measures the levels of mRNA of 84 different components of the UPR in VZV infected cells as compared to tunicamycin treated cells as a positive control and uninfected, untreated cells as a negative control. Tunicamycin is a mixture of chemicals that inhibits N-linked glycosylation in the ER with resultant protein misfolding and the UPR. We found that VZV differentially induces the UPR when compared to tunicamycin treatment. For example, tunicamycin treatment moderately increased (8 fold roughly half of the array elements while downregulating only three (one ERAD and two FOLD components. VZV infection on the other hand upregulated 33 components including a little described stress sensor CREB-H (64 fold as well as ER membrane components INSIG and gp78, which modulate cholesterol synthesis while downregulating over 20 components mostly associated with ERAD and FOLD. We hypothesize that this expression pattern is associated with an expanding ER with downregulation of active degradation by ERAD and apoptosis as the cell attempts to handle abundant viral glycoprotein synthesis.

  2. Transgenic plums (Prunus domestica L.) express the plum pox virus coat protein gene.

    Science.gov (United States)

    Scorza, R; Ravelonandro, M; Callahan, A M; Cordts, J M; Fuchs, M; Dunez, J; Gonsalves, D

    1994-11-01

    Plum hypocotyl slices were transformed with the coat protein (CP) gene of plum pox virus (PPV-CP) following cocultivation with Agrobacterium tumefaciens containing the plasmid pGA482GG/PPVCP-33. This binary vector carries the PPV-CP gene construct, as well as the chimeric neomycin phosphotransferase and β-glucuronidase genes. Integration and expression of the transferred genes into regenerated plum plants was verified through kan resistance, GUS assays, and PCR amplification of the PPV-CP gene. Twenty-two transgenic clones were identified from approximately 1800 hypocotyl slices. DNA, mRNA, and protein analyses of five transgenic plants confirmed the integration of the engineered CP gene, the accumulation of CP mRNA and of PPV-CP-immunoreactive protein. CP mRNA levels ranged from high to undetectable levels, apparently correlated with gene structure, as indicated by DNA blot analysis. Western analysis showed that transgenic plants produced amounts of CP which generally correlated with amounts of detected mRNA.

  3. Infectious bursal disease virus as a replication-incompetent viral vector expressing green fluorescent protein.

    Science.gov (United States)

    Mosley, Yung-Yi C; Wu, Ching Ching; Lin, Tsang Long

    2017-01-01

    Infectious bursal disease virus (IBDV) has been established as a replication-competent viral vector capable of carrying an epitope at multiple loci in the genome. To enhance the safety and increase the insertion capacity of IBDV as a vector, a replication-incompetent IBDV vector was developed in the present study. The feasibility of replacing one of the viral gene loci, including pvp2, vp3, vp1, or the polyprotein vp243, with the sequence of green fluorescent protein (GFP) was explored. A method combining TCID50 and immunoperoxidase monolayer assay (IPMA) determined the most feasible locus for gene replacement to be pvp2. The genomic segment containing gfp at the pvp2 locus was able to be encapsidated into IBDV particles. Furthermore, the expression of GFP in GFP-IBDV infected cells was confirmed by Western blotting and GFP-IBDV particles showed similar morphology and size to that of wildtype IBDV by electron microscopy. By providing the deleted protein in trans in a packaging cell line (pVP2-DF1), replication-incompetent GFP-IBDV particles were successfully plaque-quantified. The gfp sequence from the plaque-forming GFP-IBDV in pVP2-DF1 was confirmed by RT-PCR and sequencing. To our knowledge, GFP-IBDV developed in the present study is the first replication-incompetent IBDV vector which expresses a foreign protein in infected cells without the capability to produce viral progeny. Additionally, such replication-incompetent IBDV vectors could serve as bivalent vaccine vectors for conferring protection against infections with IBDV and other economically important, or zoonotic, avian pathogens.

  4. Ebola virus infection inversely correlates with the overall expression levels of promyelocytic leukaemia (PML protein in cultured cells

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    Szekely Laszlo

    2003-04-01

    Full Text Available Abstract Background Ebola virus causes severe, often fatal hemorrhagic fever in humans. The mechanism of escape from cellular anti-viral mechanisms is not yet fully understood. The promyelocytic leukaemia (PML associated nuclear body is part of the interferon inducible cellular defense system. Several RNA viruses have been found to interfere with the anti-viral function of the PML body. The possible interaction between Ebola virus and the PML bodies has not yet been explored. Results We found that two cell lines, Vero E6 and MCF7, support virus production at high and low levels respectively. The expression of viral proteins was visualized and quantified using high resolution immunofluorescence microscopy. Ebola encoded NP and VP35 accumulated in cytoplasmic inclusion bodies whereas VP40 was mainly membrane associated but it was also present diffusely in the cytoplasm as well as in the euchromatic areas of the nucleus. The anti-VP40 antibody also allowed the detection of extracellular virions. Interferon-alpha treatment decreased the production of all three viral proteins and delayed the development of cytopathic effects in both cell lines. Virus infection and interferon-alpha treatment induced high levels of PML protein expression in MCF7 but much less in Vero E6 cells. No disruption of PML bodies, a common phenomenon induced by a variety of different viruses, was observed. Conclusion We have established a simple fixation and immunofluorescence staining procedure that allows specific co-detection and precise sub-cellular localization of the PML nuclear bodies and the Ebola virus encoded proteins NP, VP35 and VP40 in formaldehyde treated cells. Interferon-alpha treatment delays virus production in vitro. Intact PML bodies may play an anti-viral role in Ebola infected cells.

  5. TMV-Gate vectors: Gateway compatible tobacco mosaic virus based expression vectors for functional analysis of proteins

    Science.gov (United States)

    Kagale, Sateesh; Uzuhashi, Shihomi; Wigness, Merek; Bender, Tricia; Yang, Wen; Borhan, M. Hossein; Rozwadowski, Kevin

    2012-01-01

    Plant viral expression vectors are advantageous for high-throughput functional characterization studies of genes due to their capability for rapid, high-level transient expression of proteins. We have constructed a series of tobacco mosaic virus (TMV) based vectors that are compatible with Gateway technology to enable rapid assembly of expression constructs and exploitation of ORFeome collections. In addition to the potential of producing recombinant protein at grams per kilogram FW of leaf tissue, these vectors facilitate either N- or C-terminal fusions to a broad series of epitope tag(s) and fluorescent proteins. We demonstrate the utility of these vectors in affinity purification, immunodetection and subcellular localisation studies. We also apply the vectors to characterize protein-protein interactions and demonstrate their utility in screening plant pathogen effectors. Given its broad utility in defining protein properties, this vector series will serve as a useful resource to expedite gene characterization efforts. PMID:23166857

  6. PSITE vectors for stable integration or transient expression of autofluorescent protein fusions in plants: probing Nicotiana benthamiana-virus interactions.

    Science.gov (United States)

    Chakrabarty, Romit; Banerjee, Rituparna; Chung, Sang-Min; Farman, Mark; Citovsky, Vitaly; Hogenhout, Saskia A; Tzfira, Tzvi; Goodin, Michael

    2007-07-01

    Plant functional proteomics research is increasingly dependent upon vectors that facilitate high-throughput gene cloning and expression of fusions to autofluorescent proteins. Here, we describe the pSITE family of plasmids, a new set of Agrobacterium binary vectors, suitable for the stable integration or transient expression of various autofluorescent protein fusions in plant cells. The pSITE vectors permit single-step Gateway-mediated recombination cloning for construction of binary vectors that can be used directly in transient expression studies or for the selection of transgenic plants on media containing kanamycin. These vectors can be used to express native proteins or fusions to monmeric red fluorescent protein or the enhanced green fluorescent protein and its cyan and yellow-shifted spectral variants. We have validated the vectors for use in transient expression assays and for the generation of transgenic plants. Additionally, we have generated markers for fluorescent highlighting of actin filaments, chromatin, endoplasmic reticulum, and nucleoli. Finally, we show that pSITE vectors can be used for targeted gene expression in virus-infected cells, which should facilitate high-throughput characterization of protein dynamics in host-virus interactions.

  7. Human parainfluenza virus type 3 (HPIV-3); Construction and rescue of an infectious, recombinant virus expressing the enhanced green fluorescent protein (EGFP).

    Science.gov (United States)

    The ability to rescue an infectious, recombinant, RNA virus from a cDNA clone, has led to new opportunities for measuring viral replication from a viral expressed reporter gene. In this protocol, the process of inserting enhanced green fluorescent protein (EGFP) gene into the human parainfluenza vi...

  8. High Expression of Antiviral Proteins in Mucosa from Individuals Exhibiting Resistance to Human Immunodeficiency Virus.

    Science.gov (United States)

    Gonzalez, Sandra Milena; Taborda, Natalia Andrea; Feria, Manuel Gerónimo; Arcia, David; Aguilar-Jiménez, Wbeimar; Zapata, Wildeman; Rugeles, María Teresa

    2015-01-01

    Several soluble factors have been reported to have the capacity of inhibiting HIV replication at different steps of the virus life cycle, without eliminating infected cells and through enhancement of specific cellular mechanisms. Yet, it is unclear if these antiviral factors play a role in the protection from HIV infection or in the control of viral replication. Here we evaluated two cohorts: i) one of 58 HIV-exposed seronegative individuals (HESNs) who were compared with 59 healthy controls (HCs), and ii) another of 13 HIV-controllers who were compared with 20 HIV-progressors. Peripheral blood, oral and genital mucosa and gut-associated lymphoid tissue (GALT) samples were obtained to analyze the mRNA expression of ELAFIN, APOBEC3G, SAMHD1, TRIM5α, RNase 7 and SerpinA1 using real-time PCR. HESNs exhibited higher expression of all antiviral factors in peripheral blood mononuclear cells (PBMCs), oral or genital mucosa when compared with HCs. Furthermore, HIV-controllers exhibited higher levels of SerpinA1 in GALT. These findings suggest that the activity of these factors is compartmentalized and that these proteins have a predominant role depending on the tissue to avoid the infection, reduce the viral load and modulate the susceptibility to HIV infection.

  9. High Expression of Antiviral Proteins in Mucosa from Individuals Exhibiting Resistance to Human Immunodeficiency Virus.

    Directory of Open Access Journals (Sweden)

    Sandra Milena Gonzalez

    Full Text Available Several soluble factors have been reported to have the capacity of inhibiting HIV replication at different steps of the virus life cycle, without eliminating infected cells and through enhancement of specific cellular mechanisms. Yet, it is unclear if these antiviral factors play a role in the protection from HIV infection or in the control of viral replication. Here we evaluated two cohorts: i one of 58 HIV-exposed seronegative individuals (HESNs who were compared with 59 healthy controls (HCs, and ii another of 13 HIV-controllers who were compared with 20 HIV-progressors. Peripheral blood, oral and genital mucosa and gut-associated lymphoid tissue (GALT samples were obtained to analyze the mRNA expression of ELAFIN, APOBEC3G, SAMHD1, TRIM5α, RNase 7 and SerpinA1 using real-time PCR.HESNs exhibited higher expression of all antiviral factors in peripheral blood mononuclear cells (PBMCs, oral or genital mucosa when compared with HCs. Furthermore, HIV-controllers exhibited higher levels of SerpinA1 in GALT.These findings suggest that the activity of these factors is compartmentalized and that these proteins have a predominant role depending on the tissue to avoid the infection, reduce the viral load and modulate the susceptibility to HIV infection.

  10. [Targeted inhibition of Rabies virus gene expression by a chimeric multidomain protein mediated shRNA delivery].

    Science.gov (United States)

    Yang, Ruimei; Wang, Hualei; Shan, Hu; Yang, Songtao; Xia, Xianzhu

    2016-01-04

    In this study, a new chimeric protein SEG expressed in previous work was applied to evaluate its translocating efficiency of shRNA to rabies virus infected cells in mice, meanwhile, the capability of anti-rabies virus was investigated. Rabies virus strain CVS-24 was inoculated into the hind leg to establish a mouse model of rabies in a dose of 50 LD₅₀; 12 h thereafter the mice were injected intravenously with shRNA-producing plasmid mixed with SEG. To test shRNA delivery, single-cell suspensions from brain, spleen and liver were examined by flow cytometry. Rabies virus in brain tissue of mice was detected by qRT-PCR, RT-PCR, western blot and directed immunofluorescence assay. Mice were monitored for survival and serum samples were tested for IFN-α levels. No green fluorescent protein (GFP) was seen in the spleen or liver, suggesting that SEG allows specific targeting of RV-infected cells. RT-PCR and western blot showed that mice treated with SEG-shRNA had lower rabies virus RNA and protein levels than the controls. Real-time PCR showed that rabies virus was reduced 4.88 fold compared to the mock cells. Survival of RV-infected mouse showed a significant protection from rabies virus infection by SEG-shRNA treatment. The survival was up to 50% whereas the control group all died. IFN was not induced in SEG-shRNA treated animals. shRNA-producing plasmid was specifically delivered into rabies virus infected cells using the SEG protein, and effectively inhibited rabies virus geneexpression and replication in vivo. SEG-shRNA can be used for adjuvant treatment for rabies.

  11. DNA vaccine expressing the non-structural proteins of hepatitis C virus diminishes the expression of HCV proteins in a mouse model.

    Science.gov (United States)

    Wada, Takeshi; Kohara, Michinori; Yasutomi, Yasuhiro

    2013-12-05

    Most of the people infected with hepatitis C virus (HCV) develop chronic hepatitis, which in some cases progresses to cirrhosis and ultimately to hepatocellular carcinoma. Although various immunotherapies against the progressive disease status of HCV infection have been studied, a preventive or therapeutic vaccine against this pathogen is still not available. In this study, we constructed a DNA vaccine expressing an HCV structural protein (CN2), non-structural protein (N25) or the empty plasmid DNA as a control and evaluated their efficacy as a candidate HCV vaccine in C57BL/6 and novel genetically modified HCV infection model (HCV-Tg) mice. Strong cellular immune responses to several HCV structural and non-structural proteins, characterized by cytotoxicity and interferon-gamma (IFN-γ) production, were observed in CN2 or N25 DNA vaccine-immunized C57BL/6 mice but not in empty plasmid DNA-administered mice. The therapeutic effects of these DNA vaccines were also examined in HCV-Tg mice that conditionally express HCV proteins in their liver. Though a reduction in cellular immune responses was observed in HCV-Tg mice, there was a significant decrease in the expression of HCV protein in mice administered the N25 DNA vaccine but not in mice administered the empty plasmid DNA. Moreover, both CD8(+) and CD4(+) T cells were required for the decrease of HCV protein in the liver. We found that the N25 DNA vaccine improved pathological changes in the liver compared to the empty plasmid DNA. Thus, these DNA vaccines, especially that expressing the non-structural protein gene, may be an alternative approach for treatment of individuals chronically infected with HCV. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Production of polyclonal antibodies against Pelargonium zonate spot virus coat protein expressed in Escherichia coli and application for immunodiagnosis.

    Science.gov (United States)

    Gulati-Sakhuja, Anju; Sears, John L; Nuñez, Alberto; Liu, Hsing-Yeh

    2009-09-01

    Pelargonium zonate spot virus (PZSV) is identified recently in tomato plants in the United States. To develop serological diagnostic tools for the detection of this virus, the production of good quality antibodies is a necessity. The coat protein (CP) gene of a California isolate of PZSV was cloned into a bacterial expression vector (pTriEX-4 Ek/LIC). The plasmid pTriEX-4-PZSV-CP was transformed into Escherichia coli Rosetta 2(DE3)pLacI and the recombinant PZSV-CP was expressed as a fusion protein containing N-terminal hexa-histidine and S tags. Expressed PZSV-CP was purified under denaturing conditions by affinity chromatography yielding 3mg refolded protein per 200mL of bacterial culture, and used as an antigen for raising PZSV-CP antiserum in rabbits. Specificity of the antiserum to PZSV was shown by Western blot and ELISA. When used in Western blot analysis, the antiserum was able to detect the recombinant protein, the PZSV coat protein and PZSV infected plant samples. The antiserum was successfully used in indirect-ELISA at dilutions of up to 1:16,000 to detect PZSV in infected leaf samples. Direct ELISA was successful only with denatured antigens. This is the first report on production of polyclonal antiserum against recombinant coat protein of PZSV and its use for detection and diagnosis of virus using serological methods.

  13. Virus replicon particles expressing porcine reproductive and respiratory syndrome virus proteins elicit immune priming but do not confer protection from viremia in pigs.

    Science.gov (United States)

    Eck, Melanie; Durán, Margarita García; Ricklin, Meret E; Locher, Samira; Sarraseca, Javier; Rodríguez, María José; McCullough, Kenneth C; Summerfield, Artur; Zimmer, Gert; Ruggli, Nicolas

    2016-02-19

    Porcine reproductive and respiratory syndrome virus (PRRSV) is the causative agent of one of the most devastating and economically significant viral disease of pigs worldwide. The vaccines currently available on the market elicit only limited protection. Recombinant vesicular stomatitis virus (VSV) replicon particles (VRP) have been used successfully to induce protection against influenza A virus (IAV) in chickens and bluetongue virus in sheep. In this study, VSV VRP expressing the PRRSV envelope proteins GP5, M, GP4, GP3, GP2 and the nucleocapsid protein N, individually or in combination, were generated and evaluated as a potential vector vaccine against PRRSV infection. High level expression of the recombinant PRRSV proteins was demonstrated in cell culture. However, none of the PRRSV antigens expressed from VRP, with the exception of the N protein, did induce any detectable antibody response in pigs before challenge infection with PRRSV. After challenge however, the antibody responses against GP5, GP4 and GP3 appeared in average 2 weeks earlier than in pigs vaccinated with the empty control VRP. No reduction of viremia was observed in the vaccinated group compared with the control group. When pigs were co-vaccinated with VRP expressing IAV antigens and VRP expressing PRRSV glycoproteins, only antibody responses to the IAV antigens were detectable. These data show that the VSV replicon vector can induce immune responses to heterologous proteins in pigs, but that the PRRSV envelope proteins expressed from VSV VRP are poorly immunogenic. Nevertheless, they prime the immune system for significantly earlier B-cell responses following PRRSV challenge infection.

  14. Development of a reverse genetics system to generate a recombinant Ebola virus Makona expressing a green fluorescent protein

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    Albariño, César G., E-mail: calbarino@cdc.gov; Wiggleton Guerrero, Lisa; Lo, Michael K.; Nichol, Stuart T.; Towner, Jonathan S.

    2015-10-15

    Previous studies have demonstrated the potential application of reverse genetics technology in studying a broad range of aspects of viral biology, including gene regulation, protein function, cell entry, and pathogenesis. Here, we describe a highly efficient reverse genetics system used to generate recombinant Ebola virus (EBOV) based on a recent isolate from a human patient infected during the 2014–2015 outbreak in Western Africa. We also rescued a recombinant EBOV expressing a fluorescent reporter protein from a cleaved VP40 protein fusion. Using this virus and an inexpensive method to quantitate the expression of the foreign gene, we demonstrate its potential usefulness as a tool for screening antiviral compounds and measuring neutralizing antibodies. - Highlights: • Recombinant Ebola virus (EBOV) derived from Makona variant was rescued. • New protocol for viral rescue allows 100% efficiency. • Modified EBOV expresses a green fluorescent protein from a VP40-fused protein. • Modified EBOV was tested as tool to screen antiviral compounds and measure neutralizing antibodies.

  15. A novel borna disease virus vector system that stably expresses foreign proteins from an intercistronic noncoding region.

    Science.gov (United States)

    Daito, Takuji; Fujino, Kan; Honda, Tomoyuki; Matsumoto, Yusuke; Watanabe, Yohei; Tomonaga, Keizo

    2011-12-01

    Borna disease virus (BDV), a nonsegmented, negative-strand RNA virus, infects a wide variety of mammalian species and readily establishes a long-lasting, persistent infection in brain cells. Therefore, this virus could be a promising candidate as a novel RNA virus vector enabling stable gene expression in the central nervous system (CNS). Previous studies demonstrated that the 5' untranslated region of the genome is the only site for insertion and expression of a foreign gene. In this study, we established a novel BDV vector in which an additional transcription cassette has been inserted into an intercistronic noncoding region between the viral phosphoprotein (P) and matrix (M) genes. The recombinant BDV (rBDV) carrying green fluorescent protein (GFP) between the P and M genes, rBDV P/M-GFP, expressed GFP efficiently in cultured cells and rodent brains for a long period of time without attenuation. Furthermore, we generated a nonpropagating rBDV, ΔGLLP/M, which lacks the envelope glycoprotein (G) and a splicing intron within the polymerase gene (L), by the transcomplementation system with either transient or stable expression of the G gene. Interestingly, rBDV ΔGLLP/M established a persistent infection in cultured cells with stable expression of GFP in the absence of the expression of G. Using persistently infected rBDV ΔGLLP/M-infected cells, we determined the amino acid region in the cytoplasmic tail (CT) of BDV G important for the release of infectious rBDV particles and also demonstrated that the CT region may be critical for the generation of pseudotyped rBDV having vesicular stomatitis virus G protein. Our results revealed that the newly established BDV vector constitutes an alternative tool not only for stable expression of foreign genes in the CNS but also for understanding the mechanism of the release of enveloped virions.

  16. A Novel Borna Disease Virus Vector System That Stably Expresses Foreign Proteins from an Intercistronic Noncoding Region▿

    Science.gov (United States)

    Daito, Takuji; Fujino, Kan; Honda, Tomoyuki; Matsumoto, Yusuke; Watanabe, Yohei; Tomonaga, Keizo

    2011-01-01

    Borna disease virus (BDV), a nonsegmented, negative-strand RNA virus, infects a wide variety of mammalian species and readily establishes a long-lasting, persistent infection in brain cells. Therefore, this virus could be a promising candidate as a novel RNA virus vector enabling stable gene expression in the central nervous system (CNS). Previous studies demonstrated that the 5′ untranslated region of the genome is the only site for insertion and expression of a foreign gene. In this study, we established a novel BDV vector in which an additional transcription cassette has been inserted into an intercistronic noncoding region between the viral phosphoprotein (P) and matrix (M) genes. The recombinant BDV (rBDV) carrying green fluorescent protein (GFP) between the P and M genes, rBDV P/M-GFP, expressed GFP efficiently in cultured cells and rodent brains for a long period of time without attenuation. Furthermore, we generated a nonpropagating rBDV, ΔGLLP/M, which lacks the envelope glycoprotein (G) and a splicing intron within the polymerase gene (L), by the transcomplementation system with either transient or stable expression of the G gene. Interestingly, rBDV ΔGLLP/M established a persistent infection in cultured cells with stable expression of GFP in the absence of the expression of G. Using persistently infected rBDV ΔGLLP/M-infected cells, we determined the amino acid region in the cytoplasmic tail (CT) of BDV G important for the release of infectious rBDV particles and also demonstrated that the CT region may be critical for the generation of pseudotyped rBDV having vesicular stomatitis virus G protein. Our results revealed that the newly established BDV vector constitutes an alternative tool not only for stable expression of foreign genes in the CNS but also for understanding the mechanism of the release of enveloped virions. PMID:21937656

  17. Influenza A virus protein PB1-F2 exacerbates IFN-beta expression of human respiratory epithelial cells.

    Science.gov (United States)

    Le Goffic, Ronan; Bouguyon, Edwige; Chevalier, Christophe; Vidic, Jasmina; Da Costa, Bruno; Leymarie, Olivier; Bourdieu, Christiane; Decamps, Laure; Dhorne-Pollet, Sophie; Delmas, Bernard

    2010-10-15

    The PB1-F2 protein of the influenza A virus (IAV) contributes to viral pathogenesis by a mechanism that is not well understood. PB1-F2 was shown to modulate apoptosis and to be targeted by the CD8(+) T cell response. In this study, we examined the downstream effects of PB1-F2 protein during IAV infection by measuring expression of the cellular genes in response to infection with wild-type WSN/33 and PB1-F2 knockout viruses in human lung epithelial cells. Wild-type virus infection resulted in a significant induction of genes involved in innate immunity. Knocking out the PB1-F2 gene strongly decreased the magnitude of expression of cellular genes implicated in antiviral response and MHC class I Ag presentation, suggesting that PB1-F2 exacerbates innate immune response. Biological network analysis revealed the IFN pathway as a link between PB1-F2 and deregulated genes. Using quantitative RT-PCR and IFN-β gene reporter assay, we determined that PB1-F2 mediates an upregulation of IFN-β expression that is dependent on NF-κB but not on AP-1 and IFN regulatory factor-3 transcription factors. Recombinant viruses knocked out for the PB1-F2 and/or the nonstructural viral protein 1 (the viral antagonist of the IFN response) genes provide further evidence that PB1-F2 increases IFN-β expression and that nonstructural viral protein 1 strongly antagonizes the effect of PB1-F2 on the innate response. Finally, we compared the effect of PB1-F2 variants taken from several IAV strains on IFN-β expression and found that PB1-F2-mediated IFN-β induction is significantly influenced by its amino acid sequence, demonstrating its importance in the host cell response triggered by IAV infection.

  18. Expression and stability of foreign epitopes introduced into 3A nonstructural protein of foot-and-mouth disease virus.

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    Pinghua Li

    Full Text Available Foot-and-mouth disease virus (FMDV is an aphthovirus that belongs to the Picornaviridae family and causes one of the most important animal diseases worldwide. The capacity of other picornaviruses to express foreign antigens has been extensively reported, however, little is known about FMDV. To explore the potential of FMDV as a viral vector, an 11-amino-acid (aa HSV epitope and an 8 aa FLAG epitope were introduced into the C-terminal different regions of 3A protein of FMDV full-length infectious cDNA clone. Recombinant viruses expressing the HSV or FLAG epitope were successfully rescued after transfection of both modified constructs. Immunofluorescence assay, Western blot and sequence analysis showed that the recombinant viruses stably maintained the foreign epitopes even after 11 serial passages in BHK-21 cells. The 3A-tagged viruses shared similar plaque phenotypes and replication kinetics to those of the parental virus. In addition, mice experimentally infected with the epitope-tagged viruses could induce tag-specific antibodies. Our results demonstrate that FMDV can be used effectively as a viral vector for the delivery of foreign tags.

  19. Expression of particulate-form of Japanese encephalitis virus envelope protein in a stably transfected Drosophila cell line

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    Zhang Li

    2007-02-01

    Full Text Available Abstract Background Japanese encephalitis virus (JEV, a member of the family Flaviviridae, is an important mosquito-borne human pathogen. Its envelope glycoprotein (E is the major determinant of the pathogenicity and host immune responses. In the present study, we explored the feasibility of producing recombinant JEV E protein in the virus-free Drosophila expression system. Results The coding sequence for the signal sequence of premembrane and E protein was cloned into the Drosophila expression vector pAc5.1/V5-His. A Drosophila cell line S2 was cotransfected with this construct as well as a plasmid providing hygromycin B resistance. A cell line expressing the JEV E protein was selected by immunofluoresence, confocal microscopy, and western blot analysis using three different monoclonal antibodies directed against JEV E protein. This cell line was stable in the yield of JEV E protein during two months in vitro maintenance in the presence of hygromycin B. The results showed that the recombinant E protein had an expected molecular weight of about 50 kilodalton, was immunoreactive with all three monoclonal antibodies, and found in both the cytoplasm and culture supernatant. Sucrose gradient ultracentrifugation analysis revealed that the secreted E protein product was in a particulate form. It migrated to the sucrose fraction with a density of 1.13 g/ml. Balb/c mice immunised with the sucrose fraction containing the E protein particles developed specific antibodies. These data show that functioning JEV E protein was expressed in the stable S2 cell line. Conclusion The Drosophila expression system is a more convenient, cheaper and safer approach to the production of vaccine candidates and diagnostic reagents for JEV.

  20. Expression and Immunogenicity of Two Recombinant Fusion Proteins Comprising Foot-and-Mouth Disease Virus Structural Protein VP1 and DC-SIGN-Binding Glycoproteins.

    Science.gov (United States)

    Liu, Xinsheng; Lv, Jianliang; Fang, Yuzhen; Zhou, Peng; Lu, Yanzhen; Pan, Li; Zhang, Zhongwang; Ma, Junwu; Zhang, Yongguang; Wang, Yonglu

    2017-01-01

    Improving vaccine immunogenicity by targeting antigens to dendritic cells has recently emerged as a new design strategy in vaccine development. In this study, the VP1 gene of foot-and-mouth disease virus (FMDV) serotype A was fused with the gene encoding human immunodeficiency virus (HIV) membrane glycoprotein gp120 or C2-V3 domain of hepatitis C virus (HCV) envelope glycoprotein E2, both of which are DC-SIGN-binding glycoproteins. After codon optimization, the VP1 protein and the two recombinant VP1-gp120 and VP1-E2 fusion proteins were expressed in Sf9 insect cells using the insect cell-baculovirus expression system. Western blotting showed that the VP1 protein and two recombinant VP1-gp120 and VP1-E2 fusion proteins were correctly expressed in the Sf9 insect cells and had good reactogenicity. Guinea pigs were then immunized with the purified proteins, and the resulting humoral and cellular immune responses were analyzed. The VP1-gp120 and VP1-E2 fusion proteins induced significantly higher specific anti-FMDV antibody levels than the VP1 protein and stronger cell-mediated immune responses. This study provides a new perspective for the development of novel FMDV subunit vaccines.

  1. Expression and Immunogenicity of Two Recombinant Fusion Proteins Comprising Foot-and-Mouth Disease Virus Structural Protein VP1 and DC-SIGN-Binding Glycoproteins

    Directory of Open Access Journals (Sweden)

    Xinsheng Liu

    2017-01-01

    Full Text Available Improving vaccine immunogenicity by targeting antigens to dendritic cells has recently emerged as a new design strategy in vaccine development. In this study, the VP1 gene of foot-and-mouth disease virus (FMDV serotype A was fused with the gene encoding human immunodeficiency virus (HIV membrane glycoprotein gp120 or C2-V3 domain of hepatitis C virus (HCV envelope glycoprotein E2, both of which are DC-SIGN-binding glycoproteins. After codon optimization, the VP1 protein and the two recombinant VP1-gp120 and VP1-E2 fusion proteins were expressed in Sf9 insect cells using the insect cell-baculovirus expression system. Western blotting showed that the VP1 protein and two recombinant VP1-gp120 and VP1-E2 fusion proteins were correctly expressed in the Sf9 insect cells and had good reactogenicity. Guinea pigs were then immunized with the purified proteins, and the resulting humoral and cellular immune responses were analyzed. The VP1-gp120 and VP1-E2 fusion proteins induced significantly higher specific anti-FMDV antibody levels than the VP1 protein and stronger cell-mediated immune responses. This study provides a new perspective for the development of novel FMDV subunit vaccines.

  2. Structural characterization by transmission electron microscopy and immunoreactivity of recombinant Hendra virus nucleocapsid protein expressed and purified from Escherichia coli.

    Science.gov (United States)

    Pearce, Lesley A; Yu, Meng; Waddington, Lynne J; Barr, Jennifer A; Scoble, Judith A; Crameri, Gary S; McKinstry, William J

    2015-12-01

    Hendra virus (family Paramyxoviridae) is a negative sense single-stranded RNA virus (NSRV) which has been found to cause disease in humans, horses, and experimentally in other animals, e.g. pigs and cats. Pteropid bats commonly known as flying foxes have been identified as the natural host reservoir. The Hendra virus nucleocapsid protein (HeV N) represents the most abundant viral protein produced by the host cell, and is highly immunogenic with naturally infected humans and horses producing specific antibodies towards this protein. The purpose of this study was to express and purify soluble, functionally active recombinant HeV N, suitable for use as an immunodiagnostic reagent to detect antibodies against HeV. We expressed both full-length HeV N, (HeV NFL), and a C-terminal truncated form, (HeV NCORE), using a bacterial heterologous expression system. Both HeV N constructs were engineered with an N-terminal Hisx6 tag, and purified using a combination of immobilized metal affinity chromatography (IMAC) and size exclusion chromatography (SEC). Purified recombinant HeV N proteins self-assembled into soluble higher order oligomers as determined by SEC and negative-stain transmission electron microscopy. Both HeV N proteins were highly immuno-reactive with sera from animals and humans infected with either HeV or the closely related Nipah virus (NiV), but displayed no immuno-reactivity towards sera from animals infected with a non-pathogenic paramyxovirus (CedPV), or animals receiving Equivac® (HeV G glycoprotein subunit vaccine), using a Luminex-based multiplexed microsphere assay. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

  3. Expression of hepatitis B virus large envelope protein in Escherichia coli and Saccharomyces cerevisiae.

    Science.gov (United States)

    Korec, E; Korcová, J; Palková, Z; Vondrejs, V; Korínek, V; Reinis, M; Bichko, V V; Hlozánek, I

    1989-01-01

    The gene coding for hepatitis B large envelope protein was cloned under the lac promoter in bacterial vector pUC-8 and under the ADH1 promoter in yeast expression shuttle vector pVT103-U, and expression of HBsAg in bacteria and yeast was determined. The strongest expression of large envelope protein was obtained after transformation of the protease-deficient yeast strain BJ1991. The recombinant large envelope protein did not form complex 22-nm particles and was not secreted into medium.

  4. Bovine parainfluenza virus type 3 (PIV3) expressing the respiratory syncytial virus (RSV) attachment and fusion proteins protects hamsters from challenge with human PIV3 and RSV.

    Science.gov (United States)

    Haller, Aurelia A; Mitiku, Misrach; MacPhail, Mia

    2003-08-01

    Parainfluenza virus type 3 (PIV3) and respiratory syncytial virus (RSV) are the main causes of ubiquitous acute respiratory diseases of infancy and early childhood, causing 20-25 % of pneumonia and 45-50 % of bronchiolitis in hospitalized children. The primary goal of this study was to create an effective and safe RSV vaccine based on utilizing attenuated bovine PIV3 (bPIV3) as a virus vector backbone. bPIV3 had been evaluated in human clinical trials and was shown to be attenuated and immunogenic in children as young as 2 months of age. The ability of bPIV3 to function as a virus vaccine vector was explored further by introducing the RSV attachment (G) and fusion (F) genes into the bPIV3 RNA genome. The resulting virus, bPIV3/RSV(I), contained an insert of 2900 nt, comprising two translationally competent transcription units. Despite this increase in genetic material, the virus replicated to high titres in Vero cells. This recombinant virus expressed the RSV G and F proteins sufficiently to evoke a protective immune response in hamsters upon challenge with RSV or human PIV3 and to elicit RSV neutralizing and PIV3 haemagglutinin inhibition serum antibodies. In effect, a bivalent vaccine was produced that could protect vaccinees from RSV as well as PIV3. Such a vaccine would vastly reduce the respiratory disease burden, the associated hospitalization costs and, most importantly, decrease morbidity and mortality of infants, immunocompromised individuals and the elderly.

  5. A Role for Protein Phosphatase 2A in Regulating p38 Mitogen Activated Protein Kinase Activation and Tumor Necrosis Factor-Alpha Expression during Influenza Virus Infection

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    Anna H. Y. Law

    2013-04-01

    Full Text Available Influenza viruses of avian origin continue to pose pandemic threats to human health. Some of the H5N1 and H9N2 virus subtypes induce markedly elevated cytokine levels when compared with the seasonal H1N1 virus. We previously showed that H5N1/97 hyperinduces tumor necrosis factor (TNF-alpha through p38 mitogen activated protein kinase (MAPK. However, the detailed mechanisms of p38MAPK activation and TNF-alpha hyperinduction following influenza virus infections are not known. Negative feedback regulations of cytokine expression play important roles in avoiding overwhelming production of proinflammatory cytokines. Here we hypothesize that protein phosphatases are involved in the regulation of cytokine expressions during influenza virus infection. We investigated the roles of protein phosphatases including MAPK phosphatase-1 (MKP-1 and protein phosphatase type 2A (PP2A in modulating p38MAPK activation and downstream TNF-alpha expressions in primary human monocyte-derived macrophages (PBMac infected with H9N2/G1 or H1N1 influenza virus. We demonstrate that H9N2/G1 virus activated p38MAPK and hyperinduced TNF-alpha production in PBMac when compared with H1N1 virus. H9N2/G1 induced PP2A activity in PBMac and, with the treatment of a PP2A inhibitor, p38MAPK phosphorylation and TNF-alpha production were further increased in the virus-infected macrophages. However, H9N2/G1 did not induce the expression of PP2A indicating that the activation of PP2A is not mediated by p38MAPK in virus-infected PBMac. On the other hand, PP2A may not be the targets of H9N2/G1 in the upstream of p38MAPK signaling pathways since H1N1 also induced PP2A activation in primary macrophages. Our results may provide new insights into the control of cytokine dysregulation.

  6. Recombinant Canine Distemper Virus Strain Snyder Hill Expressing Green or Red Fluorescent Proteins Causes Meningoencephalitis in the Ferret

    Science.gov (United States)

    Ludlow, M.; Nguyen, D. T.; Silin, D.; Lyubomska, O.; de Vries, R. D.; von Messling, V.; McQuaid, S.; De Swart, R. L.

    2012-01-01

    The propensity of canine distemper virus (CDV) to spread to the central nervous system is one of the primary features of distemper. Therefore, we developed a reverse genetics system based on the neurovirulent Snyder Hill (SH) strain of CDV (CDVSH) and show that this virus rapidly circumvents the blood-brain and blood-cerebrospinal fluid (CSF) barriers to spread into the subarachnoid space to induce dramatic viral meningoencephalitis. The use of recombinant CDVSH (rCDVSH) expressing enhanced green fluorescent protein (EGFP) or red fluorescent protein (dTomato) facilitated the sensitive pathological assessment of routes of virus spread in vivo. Infection of ferrets with these viruses led to the full spectrum of clinical signs typically associated with distemper in dogs during a rapid, fatal disease course of approximately 2 weeks. Comparison with the ferret-adapted CDV5804P and the prototypic wild-type CDVR252 showed that hematogenous infection of the choroid plexus is not a significant route of virus spread into the CSF. Instead, viral spread into the subarachnoid space in rCDVSH-infected animals was triggered by infection of vascular endothelial cells and the hematogenous spread of virus-infected leukocytes from meningeal blood vessels into the subarachnoid space. This resulted in widespread infection of cells of the pia and arachnoid mater of the leptomeninges over large areas of the cerebral hemispheres. The ability to sensitively assess the in vivo spread of a neurovirulent strain of CDV provides a novel model system to study the mechanisms of virus spread into the CSF and the pathogenesis of acute viral meningitis. PMID:22553334

  7. Generation and characterization of a potentially applicable Vero cell line constitutively expressing the Schmallenberg virus nucleocapsid protein.

    Science.gov (United States)

    Zhang, Yongning; Wu, Shaoqiang; Song, Shanshan; Lv, Jizhou; Feng, Chunyan; Lin, Xiangmei

    2017-02-01

    Schmallenberg virus (SBV) is a Culicoides-transmitted orthobunyavirus that poses a threat to susceptible livestock species such as cattle, sheep and goats. The nucleocapsid (N) protein of SBV is an ideal diagnostic antigen for the detection of viral infection. In this study, a stable Vero cell line, Vero-EGFP-SBV-N, constitutively expressing the SBV-N protein was established using a lentivirus system combined with puromycin selection. This cell line spontaneously emitted green fluorescent signals distributed throughout the cytoplasm, in which the expression of SBV-N fusion protein was confirmed by western blot analysis. The expression of SBV-N protein in Vero-EGFP-SBV-N cells was stable for more than fifty passages without puromycin pressure. The SBV-N fusion protein contained both an N-terminal enhanced green fluorescent protein (EGFP) tag and a C-terminal hexa-histidine (6 × His) tag, by which the N protein was successfully purified using Ni-NTA affinity chromatography. The cell line was further demonstrated to be reactive with SBV antisera and an anti-SBV monoclonal antibody in indirect immunofluorescence assays. Taken together, our results demonstrate that the Vero-EGFP-SBV-N cell line has potential for application in the serological diagnosis of SBV infection.

  8. Codon-Optimized Expression and Purification of Truncated ORF2 Protein of Hepatitis E Virus in Escherichia coli.

    Science.gov (United States)

    Farshadpour, Fatemeh; Taherkhani, Reza; Makvandi, Manoochehr; Rajabi Memari, Hamid; Samarbafzadeh, Ali Reza

    2014-07-01

    Hepatitis E virus (HEV) is a causative agent of acute hepatitis among people of different age groups and has high mortality rate of up to 30% among pregnant women. Therefore, primary prevention of HEV infection is essential. The aim of this study was to obtain the highly purified truncated open reading frames 2 (ORF2) protein, which might be a future HEV vaccine candidate. The truncated orf2 gene (orf2.1), encoding the 112-660 amino acid of HEV capsid protein sequence, was optimized, synthesized, and cloned into pBluescript II SK(+) vector. After subcloning into expression vector pET-30a (+), a 193-nucleotide fragment was deleted from the construct and the recombinant plasmid pET-30a-ORF2.2 (orf2.2 encodes 112-608 amino acid sequence of HEV capsid protein) was constructed and used for transformation of Escherichia coli BL21 cells. After induction with isopropyl-β-D-thiogalactopyranoside (IPTG) and optimizing the conditions of expression, the target protein was highly expressed and purified by Ni(2+)-chelate affinity chromatography. The expressed and purified protein was analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. The subcloning was confirmed by PCR, restriction enzyme digestion, and DNA sequencing of recombinant plasmid pET30a-ORF2.2. The results obtained from optimizing the expression conditions showed that the highest expression of the protein was obtained by adding IPTG at a final concentration of 1 mM at 37℃ for four hours. The expression and purification of truncated ORF2 protein was confirmed by SDS-PAGE and western blotting. SDS-PAGE analysis showed a protein band of about 55 kDa. SDS-PAGE of the purified protein revealed that the highest amount of target protein in elution buffer at the pH of 4.5 was obtained. The yield of the purified protein was about 1 mg/L of culture media. In this study, the optimized truncated ORF2 protein was expressed in E. coli successfully and the highly purified

  9. Mayaro virus proteins

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    J. M. S. Mezencio

    1993-06-01

    Full Text Available Mayaro virus was grown in BHK-21 cells and purified by centrifugation in a potassium-tartrate gradient (5-50%. The electron microscopy analyses of the purified virus showed an homogeneous population of enveloped particles with 69 ñ 2.3 nm in diameter. Three structural virus proteins were identified and designated pl, p2 and p3. Their average molecular weight were p1, 54 KDa; p2, 50 KDa and p3, 34 KDa. In Mayaro virus infected. Aedes albopictus cells and in BHK-21 infected cells we detected six viral proteins, in wich three of them are the structural virus proteins and the other three were products from processing of precursors of viral proteins, whose molecular weights are 62 KDa, 64 KDa and 110 KDa. The 34 KDa protein was the first viral protein sinthesized at 5 hours post-infection in both cell lines studied.

  10. Two potential recombinant rabies vaccines expressing canine parvovirus virion protein 2 induce immunogenicity to canine parvovirus and rabies virus.

    Science.gov (United States)

    Luo, Jun; Shi, Hehe; Tan, Yeping; Niu, Xuefeng; Long, Teng; Zhao, Jing; Tian, Qin; Wang, Yifei; Chen, Hao; Guo, Xiaofeng

    2016-08-17

    Both rabies virus (RABV) and canine parvovirus (CPV) cause lethal diseases in dogs. In this study, both high egg passage Flury (HEP-Flury) strains of RABV and recombinant RABV carrying double RABV glycoprotein (G) gene were used to express the CPV virion protein 2 (VP2) gene, and were designated rHEP-VP2 and, rHEP-dG-VP2 respectively. The two recombinant RABVs maintained optimal virus titration according to their viral growth kinetics assay compared with the parental strain HEP-Flury. Western blotting indicated that G protein and VP2 were expressed in vitro. The expression of VP2 in Crandell feline kidney cells post-infection by rHEP-VP2 and rHEP-dG-VP2 was confirmed by indirect immunofluorescence assay with antibody against VP2. Immunogenicity of recombinant rabies viruses was tested in Kunming mice. Both rHEP-VP2 and rHEP-dG-VP2 induced high levels of rabies antibody compared with HEP-Flury. Mice immunized with rHEP-VP2 and rHEP-dG-VP2 both had a high level of antibodies against VP2, which can protect against CPV infection. A challenge experiment indicated that more than 80% mice immunized with recombinant RABVs survived after infection of challenge virus standard 24 (CVS-24). Together, this study showed that recombinant RABVs expressing VP2 induced protective immune responses to RABV and CPV. Therefore, rHEP-VP2 and rHEP-dG-VP2 might be potential combined vaccines for RABV and CPV. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Infectious bursal disease virus recovery from Vero cells transfected with RNA transcripts is enhanced by expression of the structural proteins in trans.

    Science.gov (United States)

    Peters, M A; Lin, T L; Wu, C C

    2005-11-01

    Positive sense RNA transcripts of infectious bursal disease (IBD) virus genome segments A and B have previously been shown to be infectious. In this study we demonstrate that recovery of IBD virus from the transfection of Vero cells with positive sense RNA transcripts of genome segments A and B was enhanced by expression of the viral structural proteins VP2 with VP3 or by expression of viral polyprotein VP243 from DNA plasmids in trans. Expression of individual viral proteins VP2, VP3, or VP4 alone from DNA plasmids did not enhance IBD virus recovery. Earliest virus recovery from transfection of positive sense RNA transcripts of genomic segments A and B was at 36 h and mean titers were 10(1.8) pfu/ml. IBD virus was recovered 6 hours after transfection in cells concurrently expressing either VP2 with VP3 or VP243 and mean titers were 10(8.5) pfu/ml or 10(9.2) pfu/ml, respectively. Likewise, expression of the viral polyprotein from DNA plasmid increased the permissiveness of Vero cells for infection with non-culture adapted IBD virus. The titer of recovered non-culture adapted virus from 10(3.3) pfu/ml to 10(10.3) pfu/ml with expression of the viral polyprotein. This report is the first to describe a reverse genetics model for IBD virus with high efficiency of virus recovery for non-culture adapted strains.

  12. Characterization of oligosaccharide structures on a chimeric respiratory syncytial virus protein expressed in insect cell line Sf9

    Energy Technology Data Exchange (ETDEWEB)

    Wathen, M.W.; Aeed, P.A.; Elhammer, A.P. (Upjohn Co., Kalamazoo, MI (United States))

    1991-03-19

    The oligosaccharide structures added to a chimeric protein (FG) composed of the extracellular domains of respiratory syncytial virus F and G proteins, expressed in the insect cell line Sf9, were investigated. Cells were labeled in vivo with ({sup 3}H)glucosamine and infected wit a recombinant baculovirus containing the FG gene. The secreted chimeric protein was isolated by immunoprecipitation and subjected to oligosaccharide analysis. The FG protein contains two types of O-linked oligosaccharides: GalNAc and Gal{beta}1-3GalNAc constituting 17 and 66% of the total number of structures respectively. Only one type of N-linked oligosaccharide, constituting the remaining 17% of the structures on FG, was detected: a trimannosyl core structure with a fucose residue linked {alpha}1-6 to the asparagine-linked N-acetylglucosamine.

  13. Combined expression of p20 and p23 proteins from Citrus tristeza virus show enhanced local silencing suppressor activity

    Directory of Open Access Journals (Sweden)

    Ângela A. COSTA

    2016-07-01

    Full Text Available Viruses developed a strategy to counter-defence the posttranscriptional gene silencing mechanism (PTGS based on the activity of silencing suppressor proteins. Citrus tristeza virus (CTV, a member of the genus Closterovirus, has two suppressor proteins (p20 and p23 that target the local RNA silencing response of the host. In GFP transient co-expression assays performed on Nicotiana benthamiana 16C plants, local suppressor activity of p23 and p20 was similar. Co-expression of both proteins from a mild or a stem pitting CTV isolate showed stronger local suppression activity than either suppressor alone, with an increased GFP transcript level six- (for Gp M to nine-fold (for Gp 3a higher than non-inoculated 16C plants, in parallel with low accumulation of siRNAs. Further, GFP brightness of leaves infiltrated with Agrobacterium cultures at an OD600 of 0.5 was comparable to those infiltrated with OD600 0.25. These findings indicate that combined action of p20 and p23 proteins results in enhanced suppressor activity.

  14. Hepatitis B Virus X Upregulates HuR Protein Level to Stabilize HER2 Expression in Hepatocellular Carcinoma Cells

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    Chao-Ming Hung

    2014-01-01

    Full Text Available Hepatitis B virus- (HBV- associated hepatocellular carcinoma (HCC is the most common type of liver cancer. However, the underlying mechanism of HCC tumorigenesis is very complicated and HBV-encoded X protein (HBx has been reported to play the most important role in this process. Activation of downstream signal pathways of epidermal growth factor receptor (EGFR family is known to mediate HBx-dependent HCC tumor progression. Interestingly, HER2 (also known as ErbB2/Neu/EGFR2 is frequently overexpressed in HBx-expressing HCC patients and is associated with their poor prognosis. However, it remains unclear whether and how HBx regulates HER2 expression. In this study, our data showed that HBx expression increased HER2 protein level via enhancing its mRNA stability. The induction of RNA-binding protein HuR expression by HBx mediated the HER2 mRNA stabilization. Finally, the upregulated HER2 expression promoted the migration ability of HBx-expressing HCC cells. These findings deciphered the molecular mechanism of HBx-mediated HER2 upregulation in HBV-associated HCC.

  15. Expression of innate immune genes, proteins and microRNAs in lung tissue and leukocytes of pigs infected with influenza virus

    DEFF Research Database (Denmark)

    Skovgaard, Kerstin; Cirera, Susanna; Vasby, Ditte

    This study aimed at providing a better understanding of the involvement of innate immune factors including microRNA (miRNA) in the local and systemic host response to influenza virus infection. Twenty pigs were challenged by influenza A virus subtype H1N2. Expression of miRNA, mRNA and proteins w...

  16. Production of dengue virus envelope protein domain III-based antigens in tobacco chloroplasts using inducible and constitutive expression systems.

    Science.gov (United States)

    Gottschamel, Johanna; Lössl, Andreas; Ruf, Stephanie; Wang, Yanliang; Skaugen, Morten; Bock, Ralph; Clarke, Jihong Liu

    2016-07-01

    Dengue fever is a disease in many parts of the tropics and subtropics and about half the world's population is at risk of infection according to the World Health Organization. Dengue is caused by any of the four related dengue virus serotypes DEN-1, -2, -3 and -4, which are transmitted to people by Aedes aegypti mosquitoes. Currently there is only one vaccine (Dengvaxia(®)) available (limited to a few countries) on the market since 2015 after half a century's intensive efforts. Affordable and accessible vaccines against dengue are hence still urgently needed. The dengue envelop protein domain III (EDIII), which is capable of eliciting serotype-specific neutralizing antibodies, has become the focus for subunit vaccine development. To contribute to the development of an accessible and affordable dengue vaccine, in the current study we have used plant-based vaccine production systems to generate a dengue subunit vaccine candidate in tobacco. Chloroplast genome engineering was applied to express serotype-specific recombinant EDIII proteins in tobacco chloroplasts using both constitutive and ethanol-inducible expression systems. Expression of a tetravalent antigen fusion construct combining EDIII polypeptides from all four serotypes was also attempted. Transplastomic EDIII-expressing tobacco lines were obtained and homoplasmy was verified by Southern blot analysis. Northern blot analyses showed expression of EDIII antigen-encoding genes. EDIII protein accumulation levels varied for the different recombinant EDIII proteins and the different expression systems, and reached between 0.8 and 1.6 % of total cellular protein. Our study demonstrates the suitability of the chloroplast compartment as a production site for an EDIII-based vaccine candidate against dengue fever and presents a Gateway(®) plastid transformation vector for inducible transgene expression.

  17. Transient expression of the influenza A virus PB1-F2 protein using a plum pox virus-based vector in Nicotiana benthamiana.

    Science.gov (United States)

    Kamencayová, M; Košík, I; Hunková, J; Subr, Z W

    2014-01-01

    PB1-F2 protein of influenza A virus (IAV) was cloned in a plum pox virus (PPV) genome-based vector and attempts to express it in biolistically transfected Nicotiana benthamiana plants were performed. The vector-insert construct replicated in infected plants properly and was stable during repeated passage by mechanical inoculation, as demonstrated by disease symptoms and immunoblot detection of PPV capsid protein, while PB1-F2-specific band was more faint. We showed that it was due its low solubility. Modification of sample preparation (denaturation/solubilization preceding the centrifugation of cell debris) led to substantial signal enhancement. Maximal level of PB1-F2 expression in plants was observed 12 days post inoculation (dpi). Only 1% SDS properly solubilized the protein, other detergents were much less efficient. Solubilization with 8M urea released approximately 50% of PB1-F2 from the plant tissues, thus the treatment with this removable chaotropic agent may be a good starting point for the purification of the protein for eventual functional studies in the future.

  18. Characterization of the ectodomain of the envelope protein of dengue virus type 4: expression, membrane association, secretion and particle formation in the absence of precursor membrane protein.

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    Szu-Chia Hsieh

    Full Text Available The envelope (E of dengue virus (DENV is the major target of neutralizing antibodies and vaccine development. After biosynthesis E protein forms a heterodimer with precursor membrane (prM protein. Recent reports of infection enhancement by anti-prM monoclonal antibodies (mAbs suggest anti-prM responses could be potentially harmful. Previously, we studied a series of C-terminal truncation constructs expressing DENV type 4 prM/E or E proteins and found the ectodomain of E protein alone could be recognized by all 12 mAbs tested, suggesting E protein ectodomain as a potential subunit immunogen without inducing anti-prM response. The characteristics of DENV E protein ectodomain in the absence of prM protein remains largely unknown.In this study, we investigated the expression, membrane association, glycosylation pattern, secretion and particle formation of E protein ectodomain of DENV4 in the presence or absence of prM protein. E protein ectodomain associated with membrane in or beyond trans-Golgi and contained primarily complex glycans, whereas full-length E protein associated with ER membrane and contained high mannose glycans. In the absence of prM protein, E protein ectodomain can secrete as well as form particles of approximately 49 nm in diameter, as revealed by sucrose gradient ultracentrifugation with or without detergent and electron microscopy. Mutational analysis revealed that the secretion of E protein ectodomain was affected by N-linked glycosylation and could be restored by treatment with ammonia chloride.Considering the enhancement of DENV infectivity by anti-prM antibodies, our findings provide new insights into the expression and secretion of E protein ectodomain in the absence of prM protein and contribute to future subunit vaccine design.

  19. Designing, Construction and Expression of a Recombinant Fusion Protein Comprising the Hepatitis E Virus ORF2 and Rotavirus NSP4 in the Baculovirus Expression System

    Science.gov (United States)

    Makvandi, Manoochehr; Teimoori, Ali; Neisi, Niloofar; Samarbafzadeh, Alireza

    2016-01-01

    Background The hepatitis E virus (HEV) accounts for hepatitis E infection with relatively high mortality rate in pregnant women that can lead to fulminant hepatitis. The baculovirus expression system (BES) has the capability to produce high-level recombinant proteins and could be useful for vaccine designing. Objectives The aim of this study was designing a recombinant hepatitis E virus ORF2 and Rotavirus NSP4 (ORF2-NSP4) and to evaluating construction these recombinant proteins in the BES. Methods The truncated ORF2 gene (112-607) and truncated ORF2-NSP4 were subcloned in pFastBac1 plasmid, separately, followed by digestion and confirmed by digestion and sequencing. Then the products were transformed into Escherichia coli DH5α and retransformed in DH10Bac competent cells. Finally the white colonies containing Bacmid DNA subjected to PCR for confirming transformation. Bacmid DNA containing HEV truncated ORF2 and HEV truncated ORF2-NSP4 genes were transfected into SF9 cells using BES. The expressed proteins in the cell lysate were evaluated by SDS-PAGE and determined by the western blot assay. Results The lengths of subcloned genes, truncated ORF2 and truncated ORF2-NSP4 were 1500 and 2000bp, respectively. After retransforming in DH10Bac, the size of PCR products were 300 bp in Bacmid DNA without recombination while it was 4300 and 3800 bp in Bacmid truncated ORF2-NSP4 and Bacmid truncated ORF2 PCR products. The analysis of protein expression by SDS-PAGE and immunoblotting revealed the presence of 56 KDa for truncated ORF2 and 74.5 KDa for truncated ORF2-NSP4 proteins. Conclusions The results of the present study showed that the baculovirus expression system (SF9 cells) was able to express truncated ORF2 and truncated ORF2-NSP4 proteins as a potential candidate vaccine. PMID:28138375

  20. Cloning and expression of functional single-chain Fv antibodies directed against NIa and coat proteins of potato virus Y.

    Science.gov (United States)

    Rouis, Souad; Lafaye, Pierre; Jaoua-Aydi, Leila; Sghaier, Zidani; Ayadi, Hammadi; Gargouri-Bouzid, Radhia

    2006-10-01

    Three single-chain variable fragment (scFv) antibodies recognizing the nuclear inclusion a (NIa) and capsid proteins of potato virus Y were obtained from two mouse derived hybridoma clones secreting, respectively, an anti-NIa (22-1) and an anti-coat protein (136-13) monoclonal antibodies. The first monoclonal antibody was able to inhibit in vitro the PVY polyprotein cleavage by blocking the NIa protease activity. The amplified scFv cDNAs were first inserted into the TOPO vector and then sequenced. Several recombinant E. coli clones carrying the accurate scFv sequences were selected and the corresponding cDNAs were subcloned in pHEN phagemid and transferred in E. coli strain. The expressed scFv fragments showed an antibody activity that recognized the viral target proteins in infected tissues. Their activity was comparable to the parental monoclonal antibodies.

  1. Expression and characterization of the UL31 protein from duck enteritis virus

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    Zhu Dekang

    2009-02-01

    Full Text Available Abstract Background Previous studies indicate that the UL31 protein and its homology play similar roles in nuclear egress of all herpesviruses. However, there is no report on the UL31 gene product of DEV. In this study, we expressed and presented the basic properties of the DEV UL31 product. Results The entire ORF of the UL31 was cloned into pET 32a (+ prokaryotic expression vector. Escherichia coli BL21(DE3 competent cells were transformed with the construct followed by the induction of protein expression by the addition of IPTG. Band corresponding to the predicted sizes (55 kDa was produced on the SDS-PAGE. Over expressed 6×His-UL31 fusion protein was purified by nickel affinity chromatography. The DEV UL31 gene product has been identified by using a rabbit polyclonal antiserum raised against the purified protein. A protein of approximate 35 kDa that reacted with the antiserum was detected in immunoblots of DEV-infected cellular lysates, suggesting that the 35 kDa protein was the primary translation product of the UL31 gene. RT-PCR analyses revealed that the UL31 gene was transcribed most abundantly during the late phase of replication. Subsequently, Immunofluorescence analysis revealed that the protein was widespread speckled structures in the nuclei of infected cells. Western blotting of purified virion preparations showed that UL31 was a component of intracellular virions but was absent from mature extracellular virions. Finally, an Immunofluorescence assay was established to study the distribution of the UL31 antigen in tissues of artificially DEV infected ducks. The results showed that the UL31 antigen was primarily located in the cells of digestive organs and immunological organs. Conclusion In this work, we present the basic properties of the DEV UL31 product. The results indicate that DEV UL31 shares many similarities with its HSV or PRV homolog UL31 and suggest that functional cross-complementation is possible between members of the

  2. Myxoma virus expressing a fusion protein of interleukin-15 (IL15 and IL15 receptor alpha has enhanced antitumor activity.

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    Vesna Tosic

    Full Text Available Myxoma virus, a rabbit poxvirus, can efficiently infect various types of mouse and human cancer cells. It is a strict rabbit-specific pathogen, and is thought to be safe as a therapeutic agent in all non-rabbit hosts tested including mice and humans. Interleukin-15 (IL15 is an immuno-modulatory cytokine with significant potential for stimulating anti-tumor T lymphocytes and NK cells. Co-expression of IL15 with the α subunit of IL15 receptor (IL15Rα greatly enhances IL15 stability and bioavailability. Therefore, we engineered a new recombinant myxoma virus (vMyx-IL15Rα-tdTr, which expresses an IL15Rα-IL15 fusion protein plus tdTomato red fluorescent reporter protein. Permissive rabbit kidney epithelial (RK-13 cells infected with vMyx-IL15Rα-tdTr expressed and secreted the IL15Rα-IL15 fusion protein. Functional activity was confirmed by demonstrating that the secreted fusion protein stimulated proliferation of cytokine-dependent CTLL-2 cells. Multi-step growth curves showed that murine melanoma (B16-F10 and B16.SIY cell lines were permissive to vMyx-IL15Rα-tdTr infection. In vivo experiments in RAG1-/- mice showed that subcutaneous B16-F10 tumors treated with vMyx-IL15Rα-tdTr exhibited attenuated tumor growth and a significant survival benefit for the treated group compared to the PBS control and the control viruses (vMyx-IL15-tdTr and vMyx-tdTr. Immunohistological analysis of the subcutaneous tumors showed dramatically increased infiltration of NK cells in vMyx-IL15Rα-tdTr treated tumors compared to the controls. In vivo experiments with immunocompetent C57BL/6 mice revealed a strong infiltrate of both NK cells and CD8+ T cells in response to vMyx-IL15Rα-tdTr, and prolonged survival. We conclude that delivery of IL15Rα-IL15 in a myxoma virus vector stimulates both innate and adaptive components of the immune system.

  3. Myxoma virus expressing a fusion protein of interleukin-15 (IL15) and IL15 receptor alpha has enhanced antitumor activity.

    Science.gov (United States)

    Tosic, Vesna; Thomas, Diana L; Kranz, David M; Liu, Jia; McFadden, Grant; Shisler, Joanna L; MacNeill, Amy L; Roy, Edward J

    2014-01-01

    Myxoma virus, a rabbit poxvirus, can efficiently infect various types of mouse and human cancer cells. It is a strict rabbit-specific pathogen, and is thought to be safe as a therapeutic agent in all non-rabbit hosts tested including mice and humans. Interleukin-15 (IL15) is an immuno-modulatory cytokine with significant potential for stimulating anti-tumor T lymphocytes and NK cells. Co-expression of IL15 with the α subunit of IL15 receptor (IL15Rα) greatly enhances IL15 stability and bioavailability. Therefore, we engineered a new recombinant myxoma virus (vMyx-IL15Rα-tdTr), which expresses an IL15Rα-IL15 fusion protein plus tdTomato red fluorescent reporter protein. Permissive rabbit kidney epithelial (RK-13) cells infected with vMyx-IL15Rα-tdTr expressed and secreted the IL15Rα-IL15 fusion protein. Functional activity was confirmed by demonstrating that the secreted fusion protein stimulated proliferation of cytokine-dependent CTLL-2 cells. Multi-step growth curves showed that murine melanoma (B16-F10 and B16.SIY) cell lines were permissive to vMyx-IL15Rα-tdTr infection. In vivo experiments in RAG1-/- mice showed that subcutaneous B16-F10 tumors treated with vMyx-IL15Rα-tdTr exhibited attenuated tumor growth and a significant survival benefit for the treated group compared to the PBS control and the control viruses (vMyx-IL15-tdTr and vMyx-tdTr). Immunohistological analysis of the subcutaneous tumors showed dramatically increased infiltration of NK cells in vMyx-IL15Rα-tdTr treated tumors compared to the controls. In vivo experiments with immunocompetent C57BL/6 mice revealed a strong infiltrate of both NK cells and CD8+ T cells in response to vMyx-IL15Rα-tdTr, and prolonged survival. We conclude that delivery of IL15Rα-IL15 in a myxoma virus vector stimulates both innate and adaptive components of the immune system.

  4. Recombinant influenza virus expressing a fusion protein neutralizing epitope of respiratory syncytial virus (RSV) confers protection without vaccine-enhanced RSV disease.

    Science.gov (United States)

    Lee, Yu-Na; Hwang, Hye Suk; Kim, Min-Chul; Lee, Young-Tae; Lee, Jong Seok; Moore, Martin L; Kang, Sang-Moo

    2015-03-01

    Respiratory syncytial virus (RSV) is the leading cause of viral bronchiolitis in both children and the elderly. There is no vaccine available for the prevention of RSV infection. Here, we generated recombinant influenza virus (PR8/RSV.HA-F) expressing an RSV F243-294 neutralizing epitope in the hemagglutinin (HA) as a chimeric protein. Neutralizing antibodies specific for both RSV and influenza virus were induced by a single intranasal immunization of mice with PR8/RSV.HA-F. Mice that were immunized with PR8/RSV.HA-F were protected against RSV infection comparable with live RSV as evidenced by significant reduction of RSV lung viral loads, as well as the absence of lung eosinophilia and RSV-specific cellular immune responses. In contrast, formalin-inactivated RSV-immunized mice showed severe disease and high cellular immune responses in lungs after RSV infection. These findings support a concept that recombinant influenza virus carrying the RSV F243-294 neutralizing epitope can be developed as a promising RSV vaccine candidate which induces protective neutralizing antibodies but avoids lung immunopathology. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. [Differential display of messenger RNA and identification of selenocysteine lyase gene in hepatocellular carcinoma cells transiently expressing hepatitis C virus core protein].

    Science.gov (United States)

    Yepes, Jesús Orlando; Luz Gunturiz, María; Henao, Luis Felipe; Navas, María Cristina; Balcázar, Norman; Gómez, Luis Alberto

    2006-06-01

    Hepatitis C virus is associated with diverse liver diseases including acute and chronic hepatitis, steatosis, cirrhosis and hepatocellular carcinoma. Several studies have explored viral mechanisms involved in the establishment of persistent infection and oncogenic Hepatitis C virus. Expression assays of Hepatitis C virus core protein suggest that this protein has transforming and carcinogenic properties with multifunctional activities in host cells. Characterization of expressed genes in cells expressing Core protein is important in order to identify candidate genes responsible for these pathogenic alterations. To compare and identify gene expression profiles in the human hepatocarcinoma derived cell line, HepG2, with transient expression of Hepatitis C virus Core protein. We have used comparative PCR-mediated differential display of mRNA from HepG2 hepatocarcinoma with and without transient expression of HCV Core protein or green fluorescent protein, previously obtained using the Semliki Forest Virus-based expression, through transduction of recombinant particles, rSFV-Core and rSFV-GFP, respectively. We observed differences in band intensities of mRNA in HepG2 cells transduced with rSFV-Core compared with those detected in cells without transduction, and transduced with rSFV-GFP. Cloning and sequencing of a gene fragment (258 bp) that was expressed differentially in HepG2 cells transduced with rSFV-Core, was identified as selenocystein lyase. The results confirm that HCV Core protein expressed in HepG2 is associated with specific changes in mRNA expression, including the gene for selenocystein lyase. This gene may be involved in the pathophysiology of hepatocellular carcinoma.

  6. Vesicular stomatitis virus replicon expressing the VP2 outer capsid protein of bluetongue virus serotype 8 induces complete protection of sheep against challenge infection.

    Science.gov (United States)

    Kochinger, Stefanie; Renevey, Nathalie; Hofmann, Martin A; Zimmer, Gert

    2014-06-13

    Bluetongue virus (BTV) is an arthropod-borne pathogen that causes an often fatal, hemorrhagic disease in ruminants. Different BTV serotypes occur throughout many temperate and tropical regions of the world. In 2006, BTV serotype 8 (BTV-8) emerged in Central and Northern Europe for the first time. Although this outbreak was eventually controlled using inactivated virus vaccines, the epidemic caused significant economic losses not only from the disease in livestock but also from trade restrictions. To date, BTV vaccines that allow simple serological discrimination of infected and vaccinated animals (DIVA) have not been approved for use in livestock. In this study, we generated recombinant RNA replicon particles based on single-cycle vesicular stomatitis virus (VSV) vectors. Immunization of sheep with infectious VSV replicon particles expressing the outer capsid VP2 protein of BTV-8 resulted in induction of BTV-8 serotype-specific neutralizing antibodies. After challenge with a virulent BTV-8 strain, the vaccinated animals neither developed signs of disease nor showed viremia. In contrast, immunization of sheep with recombinant VP5 - the second outer capsid protein of BTV - did not confer protection. Discrimination of infected from vaccinated animals was readily achieved using an ELISA for detection of antibodies against the VP7 antigen. These data indicate that VSV replicon particles potentially represent a safe and efficacious vaccine platform with which to control future outbreaks by BTV-8 or other serotypes, especially in previously non-endemic regions where discrimination between vaccinated and infected animals is crucial.

  7. A GFP expressing influenza A virus to report in vivo tropism and protection by a matrix protein 2 ectodomain-specific monoclonal antibody.

    Science.gov (United States)

    De Baets, Sarah; Verhelst, Judith; Van den Hoecke, Silvie; Smet, Anouk; Schotsaert, Michael; Job, Emma R; Roose, Kenny; Schepens, Bert; Fiers, Walter; Saelens, Xavier

    2015-01-01

    The severity of influenza-related illness is mediated by many factors, including in vivo cell tropism, timing and magnitude of the immune response, and presence of pre-existing immunity. A direct way to study cell tropism and virus spread in vivo is with an influenza virus expressing a reporter gene. However, reporter gene-expressing influenza viruses are often attenuated in vivo and may be genetically unstable. Here, we describe the generation of an influenza A virus expressing GFP from a tri-cistronic NS segment. To reduce the size of this engineered gene segment, we used a truncated NS1 protein of 73 amino acids combined with a heterologous dimerization domain to increase protein stability. GFP and nuclear export protein coding information were fused in frame with the truncated NS1 open reading frame and separated from each other by 2A self-processing sites. The resulting PR8-NS1(1-73)GFP virus was successfully rescued and replicated as efficiently as the parental PR8 virus in vitro and was slightly attenuated in vivo. Flow cytometry-based monitoring of cells isolated from PR8-NS1(1-73)GFP virus infected BALB/c mice revealed that GFP expression peaked on day two in all cell types tested. In particular respiratory epithelial cells and myeloid cells known to be involved in antigen presentation, including dendritic cells (CD11c+) and inflammatory monocytes (CD11b+ GR1+), became GFP positive following infection. Prophylactic treatment with anti-M2e monoclonal antibody or oseltamivir reduced GFP expression in all cell types studied, demonstrating the usefulness of this reporter virus to analyze the efficacy of antiviral treatments in vivo. Finally, deep sequencing analysis, serial in vitro passages and ex vivo analysis of PR8-NS1(1-73)GFP virus, indicate that this virus is genetically and phenotypically stable.

  8. [Construction and identification of non-replication recombinant vaccinia virus co-expressing human papillomavirus type 16 L1/L2/E6/E7 proteins].

    Science.gov (United States)

    Huang, Wei; Tian, Hou-wen; Ren, Jiao; Fan, Jiang-tao; Zhao, Li; Bian, Tao; Lu, Zhen-hua; Ruan, Li

    2005-09-01

    To generate a human papillomavirus (HPV16) prophylactic and therapeutic vaccine candidate for cervical cancer. HPV16 major capsid protein L1 gene/minor capsid protein L2 gene and HPV16 early E6/E7 genes were inserted into a vaccinia virus expression vector. A strain of non-recombinant vaccinia virus containing the sequences was obtained through a homologous recombination and identified. DNA hybridization confirmed that the HPV16L1/L2/E6/E7 genes were integrated into vaccinia virus DNA. Western Blot result showed that full-length L1/L2/E6/E7 proteins were co-expressed in CEF cells infected with the recombinant virus. NTVJE6E7CKL1L2 could be taken as a candidate of prophylactic and therapeutic vaccine for HPV-associated tumors and their precancerous transformations.

  9. Expression of recombinant Newcastle disease virus F protein in Pichia pastoris and its immunogenicity using flagellin as the adjuvant.

    Science.gov (United States)

    Kang, Xilong; Wang, Jing; Jiao, Yang; Tang, Peipei; Song, Li; Xiong, Dan; Yin, Yuelan; Pan, Zhiming; Jiao, Xinan

    2016-12-01

    Newcastle disease (ND), a highly contagious, acute, and potent infectious disease caused by Newcastle disease virus (NDV), has a considerable impact on the global poultry industry. Although both live attenuated and inactivated vaccines are used to prevent and control the spread of ND among chickens, the increasing number of ND outbreaks in commercial poultry flocks worldwide indicates that routine vaccinations are insufficient to control ND. Hence, efforts are being invested into developing alternative and more effective vaccination strategies. In this study, we focus on F protein, the neutralizing and protective antigen of NDV, and flagellin (FliC), a toll-like receptor 5 (TLR5) agonist that is an effective inducer of innate immune responses. We amplified F gene from velogenic NDV strain F48E8. The recombinant histidine (His)-tagged F protein was efficiently expressed in a Pichia pastoris (P. pastoris) eukaryotic system and verified by sodium dodecyl sulfate polyacrylamide gel electrophoresis and western blotting. The conditions for F protein expression in P. pastoris were optimal. The immunogenicity of F protein with FliC as the adjuvant was evaluated in a C3H/HeJ mouse model. FliC was found to enhance both F-specific and NDV-specific IgG responses and F-specific cellular immune responses following intraperitoneal co-administration with F protein. Thus, the recombinant F protein expressed by P. pastoris when used with flagellin as the adjuvant has potential as a subunit vaccine candidate. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Self-assembly of virus-like particles of porcine circovirus type 2 capsid protein expressed from Escherichia coli

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    Cai Xuepeng

    2010-07-01

    Full Text Available Abstract Background Porcine circovirus 2 (PCV2 is a serious problem to the swine industry and can lead to significant negative impacts on profitability of pork production. Syndrome associated with PCV2 is known as porcine circovirus closely associated with post-weaning multisystemic wasting syndrome (PMWS. The capsid (Cap protein of PCV2 is a major candidate antigen for development of recombinant vaccine and serological diagnostic method. The recombinant Cap protein has the ability to self-assemble into virus-like particles (VLPs in vitro, it is particularly opportunity to develop the PV2 VLPs vaccine in Escherichia coli,(E.coli , because where the cost of the vaccine must be weighed against the value of the vaccinated pig, when it was to extend use the VLPs vaccine of PCV2. Results In this report, a highly soluble Cap-tag protein expressed in E.coli was constructed with a p-SMK expression vector with a fusion tag of small ubiquitin-like modifiers (SUMO. The recombinant Cap was purified using Ni2+ affinity resins, whereas the tag was used to remove the SUMO protease. Simultaneously, the whole native Cap protein was able to self-assemble into VLPs in vitro when viewed under an electron microscope. The Cap-like particles had a size and shape that resembled the authentic Cap. The result could also be applied in the large-scale production of VLPs of PCV2 and could be used as a diagnostic antigen or a potential VLP vaccine against PCV2 infection in pigs. Conclusion we have, for the first time, utilized the SUMO fusion motif to successfully express the entire authentic Cap protein of PCV2 in E. coli. After the cleavage of the fusion motif, the nCap protein has the ability to self-assemble into VLPs, which can be used as as a potential vaccine to protect pigs from PCV2-infection.

  11. A role for protein kinase PKR in the mediation of Epstein-Barr virus latent membrane protein-1-induced IL-6 and IL-10 expression.

    Science.gov (United States)

    Lin, San San; Lee, Davy C W; Law, Anna H Y; Fang, Jun Wei; Chua, Daniel T T; Lau, Allan S Y

    2010-05-01

    Expression of Epstein-Barr virus-encoded oncogenic latent membrane protein 1 (LMP1) has been substantially associated with tumorigenic transformation in the virus-infected cells. The pathogenic complexity of LMP1 is partly due to the cytokine dysregulation including IL-6 and IL-10 in perturbing the host immune responses. Here we have identified an important signaling event mediated by a dsRNA-dependent serine/threonine protein kinase, PKR, in regulating LMP1-induced IL-6 and IL-10 expression. We first demonstrated that PKR plays a significant role in mediating LMP1-induced cytokine expression by using a PKR inhibitor 2-aminopurine, and the specific role of PKR involved was confirmed by the use of siRNA oligos targeting PKR and/or a dominant-negative PKR mutant. We next revealed that PKR activity mediates LMP1-enhanced NF-kappaB nuclear translocation resulting in cytokine induction. We further demonstrated at the chromatin level that LMP1 can significantly elevate the phosphorylation of histone H3 on serine 10 (Ser 10), and the process was dependent on PKR activity. Our findings thus suggest that PKR plays an important role in mediating the cytokine gene expression induced by LMP1 through NF-kappaB activation and histone H3 Ser 10 phosphorylation. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  12. Baculovirus vectors expressing F proteins in combination with virus-induced signaling adaptor (VISA) molecules confer protection against respiratory syncytial virus infection.

    Science.gov (United States)

    Zhang, Yuan; Qiao, Lei; Hu, Xiao; Zhao, Kang; Zhang, Yanwen; Chai, Feng; Pan, Zishu

    2016-01-04

    Baculovirus has been exploited for use as a novel vaccine vector. To investigate the feasibility and efficacy of recombinant baculoviruses (rBVs) expressing respiratory syncytial virus (RSV) fusion (F) proteins, four constructs (Bac-tF/64, Bac-CF, Bac-CF/tF64 and Bac-CF/tF64-VISA) were generated. Bac-tF64 displays the F ectodomain (tF) on the envelope of rBVs, whereas Bac-CF expresses full-length F protein in transduced mammalian cells. Bac-CF/tF64 not only displays tF on the envelope but also expresses F in cells. Bac-CF/tF64-VISA comprises Bac-CF/tF64 harboring the virus-induced signaling adaptor (VISA) gene. After administration to BALB/c mice, all four vectors elicited RSV neutralizing antibody (Ab), systemic Ab (IgG, IgG1, and IgG2a), and cytokine responses. Compared with Bac-tF64, mice inoculated with Bac-CF and Bac-CF/tF64 exhibited an increased mixed Th1/Th2 cytokine response, increased ratios of IgG2a/IgG1 antibody responses, and reduced immunopathology upon RSV challenge. Intriguingly, co-expression of VISA reduced Th2 cytokine (IL-4, IL-5, and IL-10) production induced by Bac-CF/tF64, thus relieving lung pathology upon a subsequent RSV challenge. Our results indicated that the Bac-CF/tF64 vector incorporated with the VISA molecule may provide an effective vaccine strategy for protection against RSV. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Functional expression, purification, characterization, and membrane reconstitution of non-structural protein 2 from hepatitis C virus.

    Science.gov (United States)

    Fogeron, Marie-Laure; Paul, David; Jirasko, Vlastimil; Montserret, Roland; Lacabanne, Denis; Molle, Jennifer; Badillo, Aurélie; Boukadida, Célia; Georgeault, Sonia; Roingeard, Philippe; Martin, Annette; Bartenschlager, Ralf; Penin, François; Böckmann, Anja

    2015-12-01

    Non-structural protein 2 (NS2) of the hepatitis C virus (HCV) is an integral membrane protein that contains a cysteine protease and that plays a central organizing role in assembly of infectious progeny virions. While the crystal structure of the protease domain has been solved, the NS2 full-length form remains biochemically and structurally uncharacterized because recombinant NS2 could not be prepared in sufficient quantities from cell-based systems. We show here that functional NS2 in the context of the NS2-NS3pro precursor protein, ensuring NS2-NS3 cleavage, can be efficiently expressed by using a wheat germ cell-free expression system. In this same system, we subsequently successfully produce and purify milligram amounts of a detergent-solubilized form of full-length NS2 exhibiting the expected secondary structure content. Furthermore, immuno-electron microscopy analyses of reconstituted proteoliposomes demonstrate NS2 association with model membranes. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Efficient Transient Expression of Recombinant Proteins in Plants by the Novel pEff Vector Based on the Genome of Potato Virus X.

    Science.gov (United States)

    Mardanova, Eugenia S; Blokhina, Elena A; Tsybalova, Liudmila M; Peyret, Hadrien; Lomonossoff, George P; Ravin, Nikolai V

    2017-01-01

    Agroinfiltration of plant leaves with binary vectors carrying a gene of interest within a plant viral vector is a rapid and efficient method for protein production in plants. Previously, we constructed a self-replicating vector, pA7248AMV, based on the genetic elements of potato virus X (PVX), and have shown that this vector can be used for the expression of recombinant proteins in Nicotiana benthamiana. However, this vector is almost 18 kb long and therefore not convenient for genetic manipulation. Furthermore, for efficient expression of the target protein it should be co-agroinfiltrated with an additional binary vector expressing a suppressor of post-transcriptional gene silencing. Here, we improved this expression system by creating the novel pEff vector. Its backbone is about 5 kb shorter than the original vector and it contains an expression cassette for the silencing suppressor, P24, from grapevine leafroll-associated virus-2 alongside PVX genetic elements, thus eliminating the need of co-agroinfiltration. The pEff vector provides green fluorescent protein expression levels of up to 30% of total soluble protein. The novel vector was used for expression of the influenza vaccine candidate, M2eHBc, consisting of an extracellular domain of influenza virus M2 protein (M2e) fused to hepatitis B core antigen. Using the pEff system, M2eHBc was expressed to 5-10% of total soluble protein, several times higher than with original pA7248AMV vector. Plant-produced M2eHBc formed virus-like particles in vivo, as required for its use as a vaccine. The new self-replicating pEff vector could be used for fast and efficient production of various recombinant proteins in plants.

  15. Reduced expression of Jak-1 and Tyk-2 proteins leads to interferon resistance in Hepatitis C virus replicon

    Directory of Open Access Journals (Sweden)

    Luftig Ronald

    2007-09-01

    Full Text Available Abstract Background Alpha interferon in combination with ribavirin is the standard therapy for hepatitis C virus infection. Unfortunately, a significant number of patients fail to eradicate their infection with this regimen. The mechanisms of IFN-resistance are unclear. The aim of this study was to determine the contribution of host cell factors to the mechanisms of interferon resistance using replicon cell lines. Results HCV replicons with high and low activation of the IFN-promoter were cultured for a prolonged period of time in the presence of interferon-alpha (IFN-alpha2b. Stable replicon cell lines with resistant phenotype were isolated and characterized by their ability to continue viral replication in the presence of IFN-alpha. Interferon resistant cell colonies developed only in replicons having lower activation of the IFN promoter and no resistant colonies arose from replicons that exhibit higher activation of the IFN promoter. Individual cell clones were isolated and nine IFN resistant cell lines were established. HCV RNA and protein levels in these cells were not altered by IFN- alpha2b. Reduced signaling and IFN-resistant phenotype was found in all Huh-7 cell lines even after eliminating HCV, suggesting that cellular factors are involved. Resistant phenotype in the replicons is not due to lack of interferon receptor expression. All the cell lines show defect in the JAK-STAT signaling and phosphorylation of STAT 1 and STAT 2 proteins were strongly inhibited due to reduced expression of Tyk2 and Jak-1 protein. Conclusion This in vitro study provides evidence that altered expression of the Jak-Stat signaling proteins can cause IFN resistance using HCV replicon cell clones.

  16. Expression of innate immune genes, proteins and microRNAs in lung tissue of pigs infected experimentally with influenza virus (H1N2)

    DEFF Research Database (Denmark)

    Skovgaard, Kerstin; Cirera, Susanna; Vasby, Ditte

    2013-01-01

    This study aimed at providing a better understanding of the involvement of innate immune factors, including miRNA, in the local host response to influenza virus infection. Twenty pigs were challenged by influenza A virus subtype H1N2. Expression of microRNA (miRNA), mRNA and proteins were...... results suggest that, in addition to a wide range of innate immune factors, miRNAs may also be involved in controlling acute influenza infection in pigs....

  17. High yield expression in a recombinant E. coli of a codon optimized chicken anemia virus capsid protein VP1 useful for vaccine development

    OpenAIRE

    Lee, Meng-Shiou; Hseu, You-Cheng; Lai, Guan-Hua; Chang, Wen-Te; Chen, Hsi-Jien; Huang, Chi-Hung; Lee, Meng-Shiunn; Wang, Min-Ying; Kao, Jung-Yie; You, Bang-Jau; Lin, Wen- Hsin; Lien, Yi-Yang; Lin, Ming-Kuem

    2011-01-01

    Abstract Background Chicken anemia virus (CAV), the causative agent chicken anemia, is the only member of the genus Gyrovirus of the Circoviridae family. CAV is an immune suppressive virus and causes anemia, lymph organ atrophy and immunodeficiency. The production and biochemical characterization of VP1 protein and its use in a subunit vaccine or as part of a diagnostic kit would be useful to CAV infection prevention. Results Significantly increased expression of the recombinant full-length V...

  18. SIRT1 sensitizes hepatocellular carcinoma cells expressing hepatitis B virus X protein to oxidative stress-induced apoptosis.

    Science.gov (United States)

    Srisuttee, Ratakorn; Koh, Sang Seok; Malilas, Waraporn; Moon, Jeong; Cho, Il-Rae; Jhun, Byung Hak; Horio, Yoshiyuki; Chung, Young-Hwa

    2012-12-07

    We previously showed that SIRT1 deacetylase inhibits proliferation of hepatocellular carcinoma cells expressing hepatitis B virus (HBV) X protein (HBX), by destabilization of β-catenin. Here, we report another role for SIRT1 in HBX-mediated resistance to oxidative stress. Ectopic expression and enhanced activity of SIRT1 sensitize Hep3B cells stably expressing HBX to oxidative stress-induced apoptosis. SIRT1 mutant analysis showed that nuclear localization of SIRT1 is not required for sensitization of oxidation-mediated apoptosis. Furthermore, ectopic expression of SIRT1 and treatment with resveratrol (a SIRT1 activator) attenuated JNK phosphorylation, which is a prerequisite for resistance to oxidative stress-induced apoptosis. Conversely, suppression of SIRT1 activity with nicotinamide inhibited the effect of resveratrol on JNK phosphorylation, leading to restoration of resistance to oxidation-induced apoptosis. Taken together, these results suggest that up-regulation of SIRT1 under oxidative stress may be a therapeutic strategy for treatment of hepatocellular carcinoma cells related to HBV through inhibition of JNK activation. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. SIRT1 sensitizes hepatocellular carcinoma cells expressing hepatitis B virus X protein to oxidative stress-induced apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Srisuttee, Ratakorn [WCU, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Koh, Sang Seok [Immunotherapy Research Center, Korea Research Institute of Bioscience and Biotechnology, University of Science and Technology, Daejeon 305-333 (Korea, Republic of); Department of Functional Genomics, University of Science and Technology, Daejeon 305-333 (Korea, Republic of); Malilas, Waraporn; Moon, Jeong; Cho, Il-Rae [WCU, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Jhun, Byung Hak [Department of Applied Nanoscience, Pusan National University, Busan 609-735 (Korea, Republic of); Horio, Yoshiyuki [Department of Pharmacology, Sapporo Medical University, Sapporo 060-8556 (Japan); Chung, Young-Hwa, E-mail: younghc@pusan.ac.kr [WCU, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-735 (Korea, Republic of)

    2012-12-07

    Highlights: Black-Right-Pointing-Pointer Up-regulation of SIRT1 protein and activity sensitizes Hep3B-HBX cells to oxidative stress-induced apoptosis. Black-Right-Pointing-Pointer Nuclear localization of SIRT1 is not required for oxidation-induced apoptosis. Black-Right-Pointing-Pointer Ectopic expression and enhanced activity of SIRT1 attenuate JNK phosphorylation. Black-Right-Pointing-Pointer Inhibition of SIRT1 activity restores resistance to oxidation-induced apoptosis through JNK activation. -- Abstract: We previously showed that SIRT1 deacetylase inhibits proliferation of hepatocellular carcinoma cells expressing hepatitis B virus (HBV) X protein (HBX), by destabilization of {beta}-catenin. Here, we report another role for SIRT1 in HBX-mediated resistance to oxidative stress. Ectopic expression and enhanced activity of SIRT1 sensitize Hep3B cells stably expressing HBX to oxidative stress-induced apoptosis. SIRT1 mutant analysis showed that nuclear localization of SIRT1 is not required for sensitization of oxidation-mediated apoptosis. Furthermore, ectopic expression of SIRT1 and treatment with resveratrol (a SIRT1 activator) attenuated JNK phosphorylation, which is a prerequisite for resistance to oxidative stress-induced apoptosis. Conversely, suppression of SIRT1 activity with nicotinamide inhibited the effect of resveratrol on JNK phosphorylation, leading to restoration of resistance to oxidation-induced apoptosis. Taken together, these results suggest that up-regulation of SIRT1 under oxidative stress may be a therapeutic strategy for treatment of hepatocellular carcinoma cells related to HBV through inhibition of JNK activation.

  20. High yield expression in a recombinant E. coli of a codon optimized chicken anemia virus capsid protein VP1 useful for vaccine development

    Directory of Open Access Journals (Sweden)

    You Bang-Jau

    2011-07-01

    Full Text Available Abstract Background Chicken anemia virus (CAV, the causative agent chicken anemia, is the only member of the genus Gyrovirus of the Circoviridae family. CAV is an immune suppressive virus and causes anemia, lymph organ atrophy and immunodeficiency. The production and biochemical characterization of VP1 protein and its use in a subunit vaccine or as part of a diagnostic kit would be useful to CAV infection prevention. Results Significantly increased expression of the recombinant full-length VP1 capsid protein from chicken anemia virus was demonstrated using an E. coli expression system. The VP1 gene was cloned into various different expression vectors and then these were expressed in a number of different E. coli strains. The expression of CAV VP1 in E. coli was significantly increased when VP1 was fused with GST protein rather than a His-tag. By optimizing the various rare amino acid codons within the N-terminus of the VP1 protein, the expression level of the VP1 protein in E. coli BL21(DE3-pLysS was further increased significantly. The highest protein expression level obtained was 17.5 g/L per liter of bacterial culture after induction with 0.1 mM IPTG for 2 h. After purification by GST affinity chromatography, the purified full-length VP1 protein produced in this way was demonstrated to have good antigenicity and was able to be recognized by CAV-positive chicken serum in an ELISA assay. Conclusions Purified recombinant VP1 protein with the gene's codons optimized in the N-terminal region has potential as chimeric protein that, when expressed in E. coli, may be useful in the future for the development of subunit vaccines and diagnostic tests.

  1. High yield expression in a recombinant E. coli of a codon optimized chicken anemia virus capsid protein VP1 useful for vaccine development.

    Science.gov (United States)

    Lee, Meng-Shiou; Hseu, You-Cheng; Lai, Guan-Hua; Chang, Wen-Te; Chen, Hsi-Jien; Huang, Chi-Hung; Lee, Meng-Shiunn; Wang, Min-Ying; Kao, Jung-Yie; You, Bang-Jau; Lin, Wen- Hsin; Lien, Yi-Yang; Lin, Ming-Kuem

    2011-07-23

    Chicken anemia virus (CAV), the causative agent chicken anemia, is the only member of the genus Gyrovirus of the Circoviridae family. CAV is an immune suppressive virus and causes anemia, lymph organ atrophy and immunodeficiency. The production and biochemical characterization of VP1 protein and its use in a subunit vaccine or as part of a diagnostic kit would be useful to CAV infection prevention. Significantly increased expression of the recombinant full-length VP1 capsid protein from chicken anemia virus was demonstrated using an E. coli expression system. The VP1 gene was cloned into various different expression vectors and then these were expressed in a number of different E. coli strains. The expression of CAV VP1 in E. coli was significantly increased when VP1 was fused with GST protein rather than a His-tag. By optimizing the various rare amino acid codons within the N-terminus of the VP1 protein, the expression level of the VP1 protein in E. coli BL21(DE3)-pLysS was further increased significantly. The highest protein expression level obtained was 17.5 g/L per liter of bacterial culture after induction with 0.1 mM IPTG for 2 h. After purification by GST affinity chromatography, the purified full-length VP1 protein produced in this way was demonstrated to have good antigenicity and was able to be recognized by CAV-positive chicken serum in an ELISA assay. Purified recombinant VP1 protein with the gene's codons optimized in the N-terminal region has potential as chimeric protein that, when expressed in E. coli, may be useful in the future for the development of subunit vaccines and diagnostic tests.

  2. Canine parvovirus VP2 protein expressed in silkworm pupae self-assembles into virus-like particles with high immunogenicity.

    Science.gov (United States)

    Feng, Hao; Hu, Gui-qiu; Wang, Hua-lei; Liang, Meng; Liang, Hongru; Guo, He; Zhao, Pingsen; Yang, Yu-jiao; Zheng, Xue-xing; Zhang, Zhi-fang; Zhao, Yong-kun; Gao, Yu-wei; Yang, Song-tao; Xia, Xian-zhu

    2014-01-01

    The VP2 structural protein of parvovirus can produce virus-like particles (VLPs) by a self-assembly process in vitro, making VLPs attractive vaccine candidates. In this study, the VP2 protein of canine parvovirus (CPV) was expressed using a baculovirus expression system and assembled into parvovirus-like particles in insect cells and pupae. Electron micrographs of VLPs showed that they were very similar in size and morphology when compared to the wild-type parvovirus. The immunogenicity of the VLPs was investigated in mice and dogs. Mice immunized intramuscularly with purified VLPs, in the absence of an adjuvant, elicited CD4(+) and CD8(+) T cell responses and were able to elicit a neutralizing antibody response against CPV, while the oral administration of raw homogenates containing VLPs to the dogs resulted in a systemic immune response and long-lasting immunity. These results demonstrate that the CPV-VLPs stimulate both cellular and humoral immune responses, and so CPV-VLPs may be a promising candidate vaccine for the prevention of CPV-associated disease.

  3. Canine parvovirus VP2 protein expressed in silkworm pupae self-assembles into virus-like particles with high immunogenicity.

    Directory of Open Access Journals (Sweden)

    Hao Feng

    Full Text Available The VP2 structural protein of parvovirus can produce virus-like particles (VLPs by a self-assembly process in vitro, making VLPs attractive vaccine candidates. In this study, the VP2 protein of canine parvovirus (CPV was expressed using a baculovirus expression system and assembled into parvovirus-like particles in insect cells and pupae. Electron micrographs of VLPs showed that they were very similar in size and morphology when compared to the wild-type parvovirus. The immunogenicity of the VLPs was investigated in mice and dogs. Mice immunized intramuscularly with purified VLPs, in the absence of an adjuvant, elicited CD4(+ and CD8(+ T cell responses and were able to elicit a neutralizing antibody response against CPV, while the oral administration of raw homogenates containing VLPs to the dogs resulted in a systemic immune response and long-lasting immunity. These results demonstrate that the CPV-VLPs stimulate both cellular and humoral immune responses, and so CPV-VLPs may be a promising candidate vaccine for the prevention of CPV-associated disease.

  4. Respiratory syncytial virus fusion glycoprotein expressed in insect cells form protein nanoparticles that induce protective immunity in cotton rats.

    Directory of Open Access Journals (Sweden)

    Gale Smith

    Full Text Available Respiratory Syncytial Virus (RSV is an important viral agent causing severe respiratory tract disease in infants and children as well as in the elderly and immunocompromised individuals. The lack of a safe and effective RSV vaccine represents a major unmet medical need. RSV fusion (F surface glycoprotein was modified and cloned into a baculovirus vector for efficient expression in Sf9 insect cells. Recombinant RSV F was glycosylated and cleaved into covalently linked F2 and F1 polypeptides that formed homotrimers. RSV F extracted and purified from insect cell membranes assembled into 40 nm protein nanoparticles composed of multiple RSV F oligomers arranged in the form of rosettes. The immunogenicity and protective efficacy of purified RSV F nanoparticles was compared to live and formalin inactivated RSV in cotton rats. Immunized animals induced neutralizing serum antibodies, inhibited virus replication in the lungs, and had no signs of disease enhancement in the respiratory track of challenged animals. RSV F nanoparticles also induced IgG competitive for binding of palivizumab neutralizing monoclonal antibody to RSV F antigenic site II. Antibodies to this epitope are known to protect against RSV when passively administered in high risk infants. Together these data provide a rational for continued development a recombinant RSV F nanoparticle vaccine candidate.

  5. Expression of surface-bound nonstructural 1 (NS1) protein of influenza virus A H5N1 on Lactobacillus casei strain C1.

    Science.gov (United States)

    Tan, T S; Syed Hassan, S; Yap, W B

    2017-06-01

    The study aimed to construct a recombinant Lactobacillus casei expressing the nonstructural (NS) 1 protein of influenza A virus H5N1 on its cell wall. The NS1 gene was first amplified and fused to the pSGANC332 expression plasmid. The NS1 protein expression was carried out by Lact. casei strain C1. PCR screening and DNA sequencing confirmed the presence of recombinant pSG-NS1-ANC332 plasmid in Lact. casei. The plasmid was stably maintained (98·94 ± 1·65%) by the bacterium within the first 20 generations without selective pressure. The NS1 was expressed as a 49-kDa protein in association with the anchoring peptide. The yield was 1·325 ± 0·065 μg mg(-1) of bacterial cells. Lactobacillus casei expressing the NS1 on its cell wall was red-fluorescently stained, but the staining was not observed on Lact. casei carrying the empty pSGANC332. The results implied that Lact. casei strain C1 is a promising host for the expression of surface-bound NS1 protein using the pSGANC332 expression plasmid. The study has demonstrated, for the first time, the expression of nonstructural 1 (NS1) protein of influenza A virus H5N1 on the cell wall of Lactobacillus casei using the pSGANC332 expression plasmid. Display of NS1 protein on the bacterial cell wall was evident under an immunofluorescence microscopic observation. Lactobacillus casei carrying the NS1 protein could be developed into a universal oral influenza vaccine since the NS1 is highly conserved among influenza viruses. © 2017 The Society for Applied Microbiology.

  6. Expression of contactin associated protein-like 2 in a subset of hepatic progenitor cell compartment identified by gene expression profiling in hepatitis B virus-positive cirrhosis.

    Science.gov (United States)

    Wang, Huafeng; Gao, Yabo; Jin, Xiaolong; Xiao, Jiacheng

    2010-01-01

    Hepatic progenitor cells (HPC), a cell compartment capable of differentiating into hepatocytic and biliary lineages, may give rise to the formation of intermediate hepatobiliary cells (IHBC) or ductular reactions (DR). The aim of this study was to analyse the gene expression profiles of DR in cirrhosis and further investigate novel proteins expressed by HPC and their intermediate progeny. DR in hepatitis B virus (HBV)-positive cirrhotic liver tissues adjacent to hepatocellular carcinoma and interlobular bile ducts (ILBDs) in normal liver tissues were isolated by laser capture microdissection and then subjected to microarray analysis. Differential gene expression patterns were verified by quantitative reverse transcriptase-polymerase chain reaction and immunohistochemistry on serial sections. HPC and their intermediate progeny were recognized by immunostaining with hepatocytic and biliary markers [HepPar1, cytokeratin (CK)7, CK19, neural cell adhesion molecule (NCAM), epithelial cell adhesion molecule (EpCAM)]. A total of 88 genes showed upregulation in DR compared with ILBDs. Gene ontology analyses revealed that these upregulated genes were mostly associated with cell adhesion, immune response and the metabolic process. Contactin associated protein-like 2 (CNTNAP2) was first confirmed to be a novel protein expressed in a subpopulation of DR that was positive for CK7, NCAM or EpCAM. In addition, immunoreactivity for CNTNAP2 was also noted in a subset of isolated CK7-positive HPC as well as some ductular IHBC positive for CK19 and HepPar1 in DR. CNTNAP2 is specifically associated with the emergence of ductular populations and may be identified as a novel protein for defining a subset of HPC and their intermediate progeny in cirrhosis.

  7. Allergenicity assessment of the Papaya ringspot virus coat protein expressed in transgenic Rainbow papaya

    Science.gov (United States)

    The virus-resistant, transgenic commercial papaya cultivars Rainbow and SunUp (Carica papaya L.) have been consumed locally in Hawaii and elsewhere in the mainland US and Canada since their release to planters in Hawaii in 1998. These cultivars are derived from transgenic papaya line 55-1 and carry ...

  8. Expression of interleukin-10 activity by Epstein-Barr virus protein BCRF1

    NARCIS (Netherlands)

    Hsu, D. H.; de Waal Malefyt, R.; Fiorentino, D. F.; Dang, M. N.; Vieira, P.; de Vries, J.; Spits, H.; Mosmann, T. R.; Moore, K. W.

    1990-01-01

    Cytokine synthesis inhibitory factor (CSIF; interleukin-10), a product of mouse TH2 T cell clones that inhibits synthesis of cytokines by mouse TH1 T cell clones, exhibits extensive sequence similarity to an uncharacterized open reading frame in the Epstein-Barr virus BCRF1. Recombinant BCRF1

  9. Immunological characterization of a modified vaccinia virus Ankara vector expressing the human papillomavirus 16 E1 protein.

    Science.gov (United States)

    Remy-Ziller, Christelle; Germain, Claire; Spindler, Anita; Hoffmann, Chantal; Silvestre, Nathalie; Rooke, Ronald; Bonnefoy, Jean-Yves; Préville, Xavier

    2014-02-01

    Women showing normal cytology but diagnosed with a persistent high-risk human papillomavirus (HR-HPV) infection have a higher risk of developing high-grade cervical intraepithelial neoplasia and cervical cancer than noninfected women. As no therapeutic management other than surveillance is offered to these women, there is a major challenge to develop novel targeted therapies dedicated to the treatment of these patients. As such, E1 and E2 antigens, expressed early in the HPV life cycle, represent very interesting candidates. Both proteins are necessary for maintaining coordinated viral replication and gene synthesis during the differentiation process of the epithelium and are essential for the virus to complete its normal and propagative replication cycle. In the present study, we evaluated a new active targeted immunotherapeutic, a modified vaccinia virus Ankara (MVA) vector containing the E1 sequence of HPV16, aimed at inducing cellular immune responses with the potential to help and clear persistent HPV16-related infection. We carried out an extensive comparative time course analysis of the cellular immune responses induced by different schedules of immunization in C57BL/6 mice. We showed that multiple injections of MVA-E1 allowed sustained HPV16 E1-specific cellular immune responses in vaccinated mice and had no impact on the exhaustion phenotype of the generated HPV16 E1-specific CD8⁺ T cells, but they led to the differentiation of multifunctional effector T cells with high cytotoxic capacity. This study provides proof of concept that an MVA expressing HPV16 E1 can induce robust and long-lasting E1-specific responses and warrants further development of this candidate.

  10. High-level HIV-1 Nef transient expression in Nicotiana benthamiana using the P19 gene silencing suppressor protein of Artichoke Mottled Crinckle Virus

    Directory of Open Access Journals (Sweden)

    Bianco Linda

    2009-11-01

    Full Text Available Abstract Background In recent years, different HIV antigens have been successfully expressed in plants by either stable transformation or transient expression systems. Among HIV proteins, Nef is considered a promising target for the formulation of a multi-component vaccine due to its implication in the first steps of viral infection. Attempts to express Nef as a single protein product (not fused to a stabilizing protein in transgenic plants resulted in disappointingly low yields (about 0.5% of total soluble protein. In this work we describe a transient expression system based on co-agroinfiltration of plant virus gene silencing suppressor proteins in Nicotiana benthamiana, followed by a two-step affinity purification protocol of plant-derived Nef. Results The effect of three gene silencing viral suppressor proteins (P25 of Potato Virus X, P19 of either Artichoke Mottled Crinckle virus and Tomato Bushy Stunt virus on Nef transient expression yield was evaluated. The P19 protein of Artichoke Mottled Crinckle virus (AMCV-P19 gave the highest expression yield in vacuum co-agroinfiltration experiments reaching 1.3% of total soluble protein, a level almost three times higher than that previously reported in stable transgenic plants. The high yield observed in the co-agroinfiltrated plants was correlated to a remarkable decrease of Nef-specific small interfering RNAs (siRNAs indicating an effective modulation of RNA silencing mechanisms by AMCV-P19. Interestingly, we also showed that expression levels in top leaves of vacuum co-agroinfiltrated plants were noticeably reduced compared to bottom leaves. Moreover, purification of Nef from agroinfiltrated tissue was achieved by a two-step immobilized metal ion affinity chromatography protocol with yields of 250 ng/g of fresh tissue. Conclusion We demonstrated that expression level of HIV-1 Nef in plant can be improved using a transient expression system enhanced by the AMCV-P19 gene silencing suppressor

  11. High-level HIV-1 Nef transient expression in Nicotiana benthamiana using the P19 gene silencing suppressor protein of Artichoke Mottled Crinckle Virus.

    Science.gov (United States)

    Lombardi, Raffaele; Circelli, Patrizia; Villani, Maria Elena; Buriani, Giampaolo; Nardi, Luca; Coppola, Valentina; Bianco, Linda; Benvenuto, Eugenio; Donini, Marcello; Marusic, Carla

    2009-11-20

    In recent years, different HIV antigens have been successfully expressed in plants by either stable transformation or transient expression systems. Among HIV proteins, Nef is considered a promising target for the formulation of a multi-component vaccine due to its implication in the first steps of viral infection. Attempts to express Nef as a single protein product (not fused to a stabilizing protein) in transgenic plants resulted in disappointingly low yields (about 0.5% of total soluble protein). In this work we describe a transient expression system based on co-agroinfiltration of plant virus gene silencing suppressor proteins in Nicotiana benthamiana, followed by a two-step affinity purification protocol of plant-derived Nef. The effect of three gene silencing viral suppressor proteins (P25 of Potato Virus X, P19 of either Artichoke Mottled Crinckle virus and Tomato Bushy Stunt virus) on Nef transient expression yield was evaluated. The P19 protein of Artichoke Mottled Crinckle virus (AMCV-P19) gave the highest expression yield in vacuum co-agroinfiltration experiments reaching 1.3% of total soluble protein, a level almost three times higher than that previously reported in stable transgenic plants. The high yield observed in the co-agroinfiltrated plants was correlated to a remarkable decrease of Nef-specific small interfering RNAs (siRNAs) indicating an effective modulation of RNA silencing mechanisms by AMCV-P19. Interestingly, we also showed that expression levels in top leaves of vacuum co-agroinfiltrated plants were noticeably reduced compared to bottom leaves. Moreover, purification of Nef from agroinfiltrated tissue was achieved by a two-step immobilized metal ion affinity chromatography protocol with yields of 250 ng/g of fresh tissue. We demonstrated that expression level of HIV-1 Nef in plant can be improved using a transient expression system enhanced by the AMCV-P19 gene silencing suppressor protein. Moreover, plant-derived Nef was purified, with

  12. Role of hepatitis B virus X protein in regulating LIM and SH3 protein 1 (LASP-1 expression to mediate proliferation and migration of hepatoma cells

    Directory of Open Access Journals (Sweden)

    Tang Renxian

    2012-08-01

    Full Text Available Abstract Background Hepatitis B virus X protein (HBx has been shown to be responsible for the development of hepatocellular carcinoma (HCC caused by Hepatitis B virus infection. However, its potential effect on the progression of hepatocellular carcinoma remains yet unclear. LIM and SH3 protein 1 (LASP-1, a focal adhesion protein, is expressed in an up-regulation manner in the HCC tissues. LASP-1 plays an important role in the regulation of proliferation and migration of HCC. In this study, we investigated the effect of LASP-1 involved in HBx-related tumor progression. Methods LASP-1 levels in the HBx stable transfected HepG2 and Huh-7 cells were detected by RT-PCR and western blot analysis. The cellular localization of LASP-1 was assessed by immunofluorescence analysis. The activity of phosphatidylinositol 3-kinase (PI3-K pathway was demonstrated by western blot assay. The HBx-expressing cells were transfected with specific small interference RNA (siRNA against LASP-1. The proliferation and migration ability of cells were evaluated by cell viability assay and plate clone formation assay. The migration ability of cells was detected by transwell assay and wound healing assay. Results RT-PCR and western blot analysis indicated the expression of LASP-1 was increased in the stable HBx-expressing cells compared with the control cells. Immunofluorescence study revealed that the distributions of LASP-1 in HepG2-HBX cells were mainly in pseudopods and the cytoplasm while they were mainly localized in the cytoplasm of HepG2-Mock cells. The cellular localizations of LASP-1 in Huh-7-HBX cells were in the perinuclear fractions while they were mainly localized in the cytoplasm of Huh-7-Mock cells. The upregulation of LASP-1 was inhibited after treatment with LY294002, PI3-K pathway inhibitor. Overexpression of LASP-1 in the stable HBx-expressing cells enhanced the proliferation and migration ability of hepatocellular cells. siRNA-mediated LASP-1 knowdown in

  13. Immune responses induced by recombinant Bacillus subtilis expressing the spike protein of transmissible gastroenteritis virus in pigs.

    Science.gov (United States)

    Mou, Chunxiao; Zhu, Liqi; Xing, Xianping; Lin, Jian; Yang, Qian

    2016-07-01

    Transmissible gastroenteritis (TGE) causes severe diarrhea in suckling piglets, results in enormous economic loss in swine-producing areas of the world. To develop an effective, safe, and convenient vaccine for the prevention of TGE, we have constructed a recombinant Bacillus subtilis strain (B. subtilis CotGSG) displaying the transmissible gastroenteritis virus (TGEV) spike (S) protein and discussed its immune function to intestinal submucosal dendritic cells (DCs). Our results showed that the recombinant B. subtilis had the ability to recruit more DCs to sample B. subtilis CotGSG, migrate to MLNs, and induce immune responses. Immunized piglets with B. subtilis CotGSG could significantly elevate the specific SIgA titers in feces, IgG titers and neutralizing antibodies in serum. Collectively, our results suggested that recombinant B. subtilis CotGSG expressing the TGEV S protein could effectively induce immune responses via DCs, and provided a perspective on potential novel strategy and approach that may be applicable to the development of the next generation of TGEV vaccines. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Hepatitis C virus core protein overcomes H2O2-induced apoptosis by downregulating p14 expression via DNA methylation.

    Science.gov (United States)

    Seo, Young Lan; Heo, Shinhee; Jang, Kyung Lib

    2015-04-01

    Infection with hepatitis C virus (HCV) is characterized by systemic oxidative stress that is caused by either viral core protein or chronic inflammation. It is well recognized that reactive oxygen species (ROS) such as H2O2 can induce apoptotic cell death and can therefore function as anti-tumorigenic species. However, the detailed mechanisms by which ROS induce apoptotic cell death and HCV copes with the oxidative conditions are largely unknown. In the present study, we found that H2O2 induced apoptotic cell death in p53-positive human hepatocytes, but not in p53-negative human hepatocytes. For this effect, H2O2 upregulated levels of p14, increased ubiquitin-dependent degradation of mouse double minute 2 (MDM2), and reduced the interaction between MDM2 and p53 to prevent p53 degradation, resulting in accumulation of p53 and subsequent activation of p53-dependent apoptotic pathways. Interestingly, HCV core repressed p14 expression via promoter hypermethylation to abolish the potential of H2O2 to activate the p14-MDM2-p53 pathway. As a consequence, HCV core-expressing cells could overcome p53-mediated apoptosis provoked by H2O2. Taken together, HCV core could contribute to hepatocellular carcinoma formation by removing deleterious roles of ROS inducing cell death. © 2015 The Authors.

  15. Hepatitis C virus NS2 and NS3/4A proteins are potent inhibitors of host cell cytokine/chemokine gene expression

    Directory of Open Access Journals (Sweden)

    Hiscott John

    2006-09-01

    Full Text Available Abstract Background Hepatitis C virus (HCV encodes several proteins that interfere with the host cell antiviral response. Previously, the serine protease NS3/4A was shown to inhibit IFN-β gene expression by blocking dsRNA-activated retinoic acid-inducible gene I (RIG-I and Toll-like receptor 3 (TLR3-mediated signaling pathways. Results In the present work, we systematically studied the effect of all HCV proteins on IFN gene expression. NS2 and NS3/4A inhibited IFN gene activation. NS3/4A inhibited the Sendai virus-induced expression of multiple IFN (IFN-α, IFN-β and IFN-λ1/IL-29 and chemokine (CCL5, CXCL8 and CXCL10 gene promoters. NS2 and NS3/4A, but not its proteolytically inactive form NS3/4A-S139A, were found to inhibit promoter activity induced by RIG-I or its adaptor protein Cardif (or IPS-1/MAVS/VISA. Both endogenous and transfected Cardif were proteolytically cleaved by NS3/4A but not by NS2 indicating different mechanisms of inhibition of host cell cytokine production by these HCV encoded proteases. Cardif also strongly colocalized with NS3/4A at the mitochondrial membrane, implicating the mitochondrial membrane as the site for proteolytic cleavage. In many experimental systems, IFN priming dramatically enhances RNA virus-induced IFN gene expression; pretreatment of HEK293 cells with IFN-α strongly enhanced RIG-I expression, but failed to protect Cardif from NS3/4A-mediated cleavage and failed to restore Sendai virus-induced IFN-β gene expression. Conclusion HCV NS2 and NS3/4A proteins were identified as potent inhibitors of cytokine gene expression suggesting an important role for HCV proteases in counteracting host cell antiviral response.

  16. The generation of Turnip crinkle virus-like particles in plants by the transient expression of wild-type and modified forms of its coat protein

    Directory of Open Access Journals (Sweden)

    Keith eSaunders

    2015-12-01

    Full Text Available Turnip crinkle virus (TCV, a member of the genus carmovirus of the Tombusviridae family, has a genome consisting of a single positive-sense RNA molecule that is encapsidated in an icosahedral particle composed of 180 copies of a single type of coat protein. We have employed the CPMV-HT transient expression system to investigate the formation of TCV-like particles following the expression of the wild-type coat protein or modified forms of it that contain either deletions and/or additions insertions. Transient expression of the coat protein in plants results in the formation of capsid structures that morphologically resemble TCV virions (T=3 structure but encapsidate heterogeneous cellular RNAs, rather than the specific TCV coat protein messenger RNA. Expression of an amino-terminal deleted form of the coat protein resulted in the formation of smaller T=1 structures that are free of RNA. The possibility of utilising TCV as a carrier for the presentation of foreign proteins on the particle surface was also explored by fusing the sequence of GFP to the C-terminus of the coat protein. The expression of coat protein-GFP hybrids permitted the formation of VLPs but the yield of particles is diminished compared to the yield obtained with unmodified coat protein. Our results confirm the importance of the N-terminus of the coat protein for the encapsidation of RNA and show that the coat protein’s exterior P domain plays a key role in particle formation.

  17. Membrane and envelope virus proteins co-expressed as lysosome associated membrane protein (LAMP fused antigens: a potential tool to develop DNA vaccines against flaviviruses

    Directory of Open Access Journals (Sweden)

    Rafael Dhalia

    2009-12-01

    Full Text Available Vaccination is the most practical and cost-effective strategy to prevent the majority of the flavivirus infection to which there is an available vaccine. However, vaccines based on attenuated virus can potentially promote collateral side effects and even rare fatal reactions. Given this scenario, the developent of alternative vaccination strategies such as DNA-based vaccines encoding specific flavivirus sequences are being considered. Endogenous cytoplasmic antigens, characteristically plasmid DNA-vaccine encoded, are mainly presented to the immune system through Major Histocompatibility Complex class I - MHC I molecules. The MHC I presentation via is mostly associated with a cellular cytotoxic response and often do not elicit a satisfactory humoral response. One of the main strategies to target DNA-encoded antigens to the MHC II compartment is expressing the antigen within the Lysosome-Associated Membrane Protein (LAMP. The flavivirus envelope protein is recognized as the major virus surface protein and the main target for neutralizing antibodies. Different groups have demonstrated that co-expression of flavivirus membrane and envelope proteins in mammalian cells, fused with the carboxyl-terminal of LAMP, is able to induce satisfactory levels of neutralizing antibodies. Here we reviewed the use of the envelope flavivirus protein co-expression strategy as LAMP chimeras with the aim of developing DNA vaccines for dengue, West Nile and yellow fever viruses.A vacinação é a estratégia mais prática e o melhor custo-benefício para prevenir a maioria das infecções dos flavivirus, para os quais existe vacina disponível. Entretanto, as vacinas baseadas em vírus atenuados podem potencialmente promover efeitos colaterais e, mais raramente, reações fatais. Diante deste cenário, o desenvolvimento de estratégias alternativas de vacinação, como vacinas baseadas em DNA codificando seqüências específicas dos flavivirus, está sendo considerado

  18. Lichen planus remission is associated with a decrease of human herpes virus type 7 protein expression in plasmacytoid dendritic cells

    NARCIS (Netherlands)

    de Vries, H.J.C.; Teunissen, M.B.M.; Zorgdrager, F.; Picavet, D.; Cornelissen, M

    2007-01-01

    The cause of lichen planus is still unknown. Previously we showed human herpes virus 7 (HHV-7) DNA and proteins in lesional lichen planus skin, and significantly less in non-lesional lichen planus, psoriasis or healthy skin. Remarkably, lesional lichen planus skin was infiltrated with plasmacytoid

  19. Live-attenuated auxotrophic mutant of Salmonella Typhimurium expressing immunogenic HA1 protein enhances immunity and protective efficacy against H1N1 influenza virus infection.

    Science.gov (United States)

    Kamble, Nitin Machindra; Hyoung, Kim Je; Lee, John Hwa

    2017-07-01

    To evaluate the efficacy of attenuated Salmonella Typhimurium (JOL912) as a live bacterial vaccine vector. The JOL912 engineered to deliver HA1 protein from influenza A/Puerto Rico/8/1934 (H1N1; PR8) virus was coined as JOL1635 and further evaluated for immunogenicity and protective efficacy. The JOL1635 stably harbored the HA1 gene within pMMP65 plasmid with periplasmic expression and effective delivery of HA1 protein to RAW264.7 cells. The JOL1635 immunized chickens showed the significant increase in HA1-specific IgG, sIgA antibody, IFN-γ, IL-6 cytokine and cellular immune responses. The postoral challenge, the JOL1635-immunized chickens showed a faster clearance of PR8 virus cloacal shedding than the control group. Generated JOL1635 can establish specific immunogenicity and protection against the PR8 virus in chickens.

  20. Protective role of amantadine in mitochondrial dysfunction and oxidative stress mediated by hepatitis C virus protein expression.

    Science.gov (United States)

    Quarato, Giovanni; Scrima, Rosella; Ripoli, Maria; Agriesti, Francesca; Moradpour, Darius; Capitanio, Nazzareno; Piccoli, Claudia

    2014-06-15

    Amantadine is an antiviral and antiparkinsonian drug that has been evaluated in combination therapies against hepatitis C virus (HCV) infection. Controversial results have been reported concerning its efficacy, and its mechanism of action remains unclear. Data obtained in vitro suggested a role of amantadine in inhibiting HCV p7-mediated cation conductance. In keeping with the fact that mitochondria are responsible to ionic fluxes and that HCV infection impairs mitochondrial function, we investigated a potential role of amantadine in modulating mitochondrial function. Using a well-characterized inducible cell line expressing the full-length HCV polyprotein, we found that amantadine not only prevented but also rescued HCV protein-mediated mitochondrial dysfunction. Specifically, amantadine corrected (i) overload of mitochondrial Ca²⁺; (ii) inhibition of respiratory chain activity and oxidative phosphorylation; (iii) reduction of membrane potential; and (iv) overproduction of reactive oxygen species. The effects of amantadine were observed within 15 min following drug administration and confirmed in Huh-7.5 cells transfected with an infectious HCV genome. These effects were also observed in cells expressing subgenomic HCV constructs, indicating that they are not mediated or only in part mediated by p7. Single organelle analyzes carried out on isolated mouse liver mitochondria demonstrated that amantadine induces hyperpolarization of the membrane potential. Moreover, amantadine treatment increased the calcium threshold required to trigger mitochondrial permeability transition opening. In conclusion, these results support a role of amantadine in preserving cellular bioenergetics and redox homeostasis in HCV-infected cells and unveil an effect of the drug which might be exploited for a broader therapeutic utilization. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. A novel two-component Tobacco mosaic virus-based vector system for high-level expression of multiple therapeutic proteins including a human monoclonal antibody in plants.

    Science.gov (United States)

    Roy, Gourgopal; Weisburg, Sangeetha; Rabindran, Shailaja; Yusibov, Vidadi

    2010-09-15

    Expression of multiple therapeutic proteins from Tobacco mosaic virus (TMV)-based vectors was not successful when plants were coinoculated with a mixture of two TMV vectors engineered to express two foreign genes individually. Here, we have engineered and developed a defective RNA (dRNA)-based TMV vector (dRT-V) that utilizes two components of the same virus, with the dRNA component depending on the helper virus for replication. Agrobacterium-mediated coinoculation of Nicotiana benthamiana plants with both components of the dRT-V resulted in high-level expression of a human growth hormone and a lichenase-fused lethal factor protein of Bacillus anthracis. Furthermore, both heavy and light chains were expressed and assembled into a monoclonal antibody (mAb) specific to the protective antigen of B. anthracis, and the average yield of the purified antibody obtained was 120 mg/kg of fresh tissue. Our data suggest that dRT-V has a potential for rapid, cost-effective, large-scale manufacturing of multiple therapeutic proteins including mAbs in response to any biological emergencies. Copyright 2010 Elsevier Inc. All rights reserved.

  2. Structure and Immunogenicity of Alternative Forms of the Simian Immunodeficiency Virus Gag Protein Expressed Using Venezuelan Equine Encephalitis Virus Replicon Particles

    OpenAIRE

    Cecil, Chad; West, Ande; Collier, Martha; Jurgens, Christy; Madden, Victoria; Whitmore, Alan; Johnston, Robert; Moore, Dominic T.; Swanstrom, Ronald; Davis, Nancy L.

    2007-01-01

    Venezuelan equine encephalitis virus replicon particles (VRP) were engineered to express different forms of SIV Gag to compare expression in vitro, formation of intra- and extracellular structures and induction of humoral and cellular immunity in mice. The three forms examined were full-length myristylated SIV Gag (Gagmyr+), full-length Gag lacking the myristylation signal (Gagmyr-), or a truncated form of Gagmyr- comprising only the matrix and capsid domains (MA/CA). Comparison of VRP-infect...

  3. The Central Conserved Region (CCR) of Respiratory Syncytial Virus (RSV) G Protein Modulates Host miRNA Expression and Alters the Cellular Response to Infection

    Science.gov (United States)

    Haynes, Lia M.; Anderson, Larry J.

    2017-01-01

    Respiratory Syncytial Virus (RSV) infects respiratory epithelial cells and deregulates host gene expression by many mechanisms including expression of RSV G protein (RSV G). RSV G protein encodes a central conserved region (CCR) containing a CX3C motif that functions as a fractalkine mimic. Disruption of the CX3C motif (a.a. 182–186) located in the CCR of the G protein has been shown to affect G protein function in vitro and the severity of RSV disease pathogenesis in vivo. We show that infection of polarized Calu3 respiratory cells with recombinant RSV having point mutations in Cys173 and 176 (C173/176S) (rA2-GC12), or Cys186 (C186S) (rA2-GC4) is associated with a decline in the integrity of polarized Calu-3 cultures and decreased virus production. This is accompanied with downregulation of miRNAs let-7f and miR-24 and upregulation of interferon lambda (IFNλ), a primary antiviral cytokine for RSV in rA2-GC12/rA2-GC4 infected cells. These results suggest that residues in the cysteine noose region of RSV G protein can modulate IFN λ expression accompanied by downregulation of miRNAs, and are important for RSV G protein function and targeting. PMID:28671606

  4. Quantitative analysis of differentially expressed saliva proteins in human immunodeficiency virus type 1 (HIV-1) infected individuals

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Nawei; Zhang, Zhenyu [Beijing Chaoyang Hospital Affiliated Capital Medical University, Beijing (China); Feng, Shan [MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing (China); Wang, Qingtao [Beijing Chaoyang Hospital Affiliated Capital Medical University, Beijing (China); Malamud, Daniel [NYU College of Dentistry, 345 East 24th Street, New York, NY 10010 (United States); Deng, Haiteng, E-mail: dht@mail.tsinghua.edu.cn [MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing (China)

    2013-04-24

    Highlights: ► A high-throughput method for profiling and quantification of the differentially expressed proteins in saliva samples was developed. ► Identified that DMBT1, S100A7, S100A8, S100A9 and alpha defensin were up-regulated in saliva from HIV-1 seropositive patients. ► Established analytical strategies are translatable to the clinical setting. -- Abstract: In the present study, we have established a new methodology to analyze saliva proteins from HIV-1-seropositive patients before highly active antiretroviral therapy (HAART) and seronegative controls. A total of 593 and 601 proteins were identified in the pooled saliva samples from 5 HIV-1 subjects and 5 controls, respectively. Forty-one proteins were found to be differentially expressed. Bioinformatic analysis of differentially expressed salivary proteins showed an increase of antimicrobial proteins and decrease of protease inhibitors upon HIV-1 infection. To validate some of these differentially expressed proteins, a high-throughput quantitation method was established to determine concentrations of 10 salivary proteins in 40 individual saliva samples from 20 seropositive patients before HAART and 20 seronegative subjects. This method was based on limited protein separation within the zone of the stacking gel of the 1D SDS PAGE and using isotope-coded synthetic peptides as internal standards. The results demonstrated that a combination of protein profiling and targeted quantitation is an efficient method to identify and validate differentially expressed salivary proteins. Expression levels of members of the calcium-binding S100 protein family and deleted in malignant brain tumors 1 protein (DMBT1) were up-regulated while that of Mucin 5B was down-regulated in HIV-1 seropositive saliva samples, which may provide new perspectives for monitoring HIV-infection and understanding the mechanism of HIV-1 infectivity.

  5. Goose parvovirus structural proteins expressed by recombinant baculoviruses self-assemble into virus-like particles with strong immunogenicity in goose

    Energy Technology Data Exchange (ETDEWEB)

    Ju, Huanyu; Wei, Na; Wang, Qian; Wang, Chunyuan; Jing, Zhiqiang; Guo, Lu; Liu, Dapeng; Gao, Mingchun; Ma, Bo [College of Veterinary Medicine, Northeast Agricultural University, Harbin, Heilongjiang 150030 (China); Wang, Junwei, E-mail: jwwang@neau.edu.cn [College of Veterinary Medicine, Northeast Agricultural University, Harbin, Heilongjiang 150030 (China)

    2011-05-27

    Highlights: {yields} All three capsid proteins can be expressed in insect cells in baculovirus expression system. {yields} All three recombinant proteins were spontaneously self-assemble into virus-like particles whose size and appearance were similar to those of native purified GPV virions. {yields} The immunogenicity of GPV-VLPs was better than commercial inactivated vaccine and attenuated vaccine. -- Abstract: Goose parvovirus (GPV), a small non-enveloped ssDNA virus, can cause Derzsy's disease, and three capsid proteins of VP1, VP2, and VP3 are encoded by an overlapping nucleotide sequence. However, little is known on whether recombinant viral proteins (VPs) could spontaneously assemble into virus-like particles (VLPs) in insect cells and whether these VLPs could retain their immunoreactivity and immunogenicity in susceptible geese. To address these issues, genes for these GPV VPs were amplified by PCR, and the recombinant VPs proteins were expressed in insect cells using a baculovirus expression system for the characterization of their structures, immunoreactivity, and immunogenicity. The rVP1, rVP2, and rVP3 expressed in Sf9 cells were detected by anti-GPV sera, anti-VP3 sera, and anti-His antibodies, respectively. Electron microscopy revealed that these rVPs spontaneously assembled into VLPs in insect cells, similar to that of the purified wild-type GPV virions. In addition, vaccination with individual types of VLPs, particularly with the rVP2-VLPs, induced higher titers of antibodies and neutralized different strains of GPVs in primary goose and duck embryo fibroblast cells in vitro. These data indicated that these VLPs retained immunoreactivity and had strong immunogenicity in susceptible geese. Therefore, our findings may provide a framework for development of new vaccines for the prevention of Derzsy's disease and vehicles for the delivery of drugs.

  6. Retention of a recombinant GFP protein expressed by the yellow fever 17D virus in the E/NS1 intergenic region in the endoplasmic reticulum

    Directory of Open Access Journals (Sweden)

    Gisela Freitas Trindade

    2012-03-01

    Full Text Available The flaviviral envelope proteins, E protein and precursor membrane protein, are mainly associated with the endoplasmic reticulum (ER through two transmembrane (TM domains that are exposed to the luminal face of this compartment. Their retention is associated with the viral assembly process. ER-retrieval motifs were mapped at the carboxy terminus of these envelope proteins. A recombinant yellow fever (YF 17D virus expressing the reporter green fluorescent protein (GFP with the stem-anchor (SA region of E protein fused to its carboxy terminus was subjected to distinct genetic mutations in the SA sequence to investigate their effect on ER retention. Initially, we introduced progressive deletions of the stem elements (H1, CS and H2. In a second set of mutants, the effect of a length increase for the first TM anchor region was evaluated either by replacing it with the longer TM of human LAMP-1 or by the insertion of the VALLLVA sequence into its carboxy terminus. We did not detect any effect on the GFP localisation in the cell, which remained associated with the ER. Further studies should be undertaken to elucidate the causes of the ER retention of recombinant proteins expressed at the intergenic E/NS1 region of the YF 17D virus polyprotein.

  7. Novel Strategy to Control Transgene Expression Mediated by a Sendai Virus-Based Vector Using a Nonstructural C Protein and Endogenous MicroRNAs.

    Directory of Open Access Journals (Sweden)

    Masayuki Sano

    Full Text Available Tissue-specific control of gene expression is an invaluable tool for studying various biological processes and medical applications. Efficient regulatory systems have been utilized to control transgene expression in various types of DNA viral or integrating viral vectors. However, existing regulatory systems are difficult to transfer into negative-strand RNA virus vector platforms because of significant differences in their transcriptional machineries. In this study, we developed a novel strategy for regulating transgene expression mediated by a cytoplasmic RNA vector based on a replication-defective and persistent Sendai virus (SeVdp. Because of the capacity of Sendai virus (SeV nonstructural C proteins to specifically inhibit viral RNA synthesis, overexpression of C protein significantly reduced transgene expression mediated by SeVdp vectors. We found that SeV C overexpression concomitantly reduced SeVdp mRNA levels and genomic RNA synthesis. To control C expression, target sequences for an endogenous microRNA were incorporated into the 3' untranslated region of the C genes. Incorporation of target sequences for miR-21 into the SeVdp vector restored transgene expression in HeLa cells by decreasing C expression. Furthermore, the SeVdp vector containing target sequences for let-7a enabled cell-specific control of transgene expression in human fibroblasts and induced pluripotent stem cells. Our findings demonstrate that SeV C can be used as an effective regulator for controlling transgene expression. This strategy will contribute to efficient and less toxic SeVdp-mediated gene transfer in various biological applications.

  8. Incidence of Lettuce mosaic virus in lettuce and its detection by polyclonal antibodies produced against recombinant coat protein expressed in Escherichia coli.

    Science.gov (United States)

    Sharma, Prachi; Sharma, Susheel; Singh, Jasvir; Saha, Swati; Baranwal, V K

    2016-04-01

    Lettuce mosaic virus (LMV), a member of the genus Potyvirus of family Potyviridae, causes mosaic disease in lettuce has recently been identified in India. The virus is seed borne and secondary infection occurs through aphids. To ensure virus freedom in seeds it is important to develop diagnostic tools, for serological methods the production of polyclonal antibodies is a prerequisite. The coat protein (CP) gene of LMV was amplified, cloned and expressed using pET-28a vector in Escherichia coli BL21DE3 competent cells. The LMV CP was expressed as a fusion protein containing a fragment of the E. coli His tag. The LMV CP/His protein reacted positively with a commercial antiserum against LMV in an immunoblot assay. Polyclonal antibodies purified from serum of rabbits immunized with the fusion protein gave positive results when LMV infected lettuce (Lactuca sativa) was tested at 1:1000 dilution in PTA-ELISA. These were used for specific detection of LMV in screening lettuce accessions. The efficacy of the raised polyclonal antiserum was high and it can be utilized in quarantine and clean seed production. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Transient expression of Human papillomavirus type 16 L2 epitope fused to N- and C-terminus of coat protein of Potato virus X in plants.

    Science.gov (United States)

    Cerovska, Noemi; Hoffmeisterova, Hana; Moravec, Tomas; Plchova, Helena; Folwarczna, Jitka; Synkova, Helena; Ryslava, Helena; Ludvikova, Viera; Smahel, Michal

    2012-03-01

    Transient expression of foreign genes based on plant viral vectors is a suitable system for the production of relevant immunogens that can be used for the development of a new generation of vaccines against a variety of infectious diseases. In the present study the epitope derived from HPV-16 L2 minor capsid protein (amino acids 108-120) was expressed from Potato virus X (PVX)-based vector pGR106 as N- or C-terminal fusion with the PVX coat protein (PVX CP) in transgenic Nicotiana benthamiana plants. The fusion protein L2 108-120-PVX CP was successfully expressed in plants at a level of 170 mg/kg of fresh leaf tissue. The C-terminal fusion protein PVX CP- L2 108-120 was expressed using mutated vector sequence to avoid homologous recombination at a level of 8 mg/kg of fresh leaf tissue. Immunogenicity of L2 108-120-PVX CP virus-like particles was tested after immunization of mice by subcutaneous injection or tattoo administration. In animal sera the antibodies against the PVX CP and the L2 108-120 epitope were found after both methods of vaccine delivery.

  10. Diffusion of information throughout the host interactome reveals gene expression variations in network proximity to target proteins of hepatitis C virus.

    Directory of Open Access Journals (Sweden)

    Ettore Mosca

    Full Text Available Hepatitis C virus infection is one of the most common and chronic in the world, and hepatitis associated with HCV infection is a major risk factor for the development of cirrhosis and hepatocellular carcinoma (HCC. The rapidly growing number of viral-host and host protein-protein interactions is enabling more and more reliable network-based analyses of viral infection supported by omics data. The study of molecular interaction networks helps to elucidate the mechanistic pathways linking HCV molecular activities and the host response that modulates the stepwise hepatocarcinogenic process from preneoplastic lesions (cirrhosis and dysplasia to HCC. Simulating the impact of HCV-host molecular interactions throughout the host protein-protein interaction (PPI network, we ranked the host proteins in relation to their network proximity to viral targets. We observed that the set of proteins in the neighborhood of HCV targets in the host interactome is enriched in key players of the host response to HCV infection. In opposition to HCV targets, subnetworks of proteins in network proximity to HCV targets are significantly enriched in proteins reported as differentially expressed in preneoplastic and neoplastic liver samples by two independent studies. Using multi-objective optimization, we extracted subnetworks that are simultaneously "guilt-by-association" with HCV proteins and enriched in proteins differentially expressed. These subnetworks contain established, recently proposed and novel candidate proteins for the regulation of the mechanisms of liver cells response to chronic HCV infection.

  11. Diffusion of Information throughout the Host Interactome Reveals Gene Expression Variations in Network Proximity to Target Proteins of Hepatitis C Virus

    Science.gov (United States)

    Milanesi, Luciano

    2014-01-01

    Hepatitis C virus infection is one of the most common and chronic in the world, and hepatitis associated with HCV infection is a major risk factor for the development of cirrhosis and hepatocellular carcinoma (HCC). The rapidly growing number of viral-host and host protein-protein interactions is enabling more and more reliable network-based analyses of viral infection supported by omics data. The study of molecular interaction networks helps to elucidate the mechanistic pathways linking HCV molecular activities and the host response that modulates the stepwise hepatocarcinogenic process from preneoplastic lesions (cirrhosis and dysplasia) to HCC. Simulating the impact of HCV-host molecular interactions throughout the host protein-protein interaction (PPI) network, we ranked the host proteins in relation to their network proximity to viral targets. We observed that the set of proteins in the neighborhood of HCV targets in the host interactome is enriched in key players of the host response to HCV infection. In opposition to HCV targets, subnetworks of proteins in network proximity to HCV targets are significantly enriched in proteins reported as differentially expressed in preneoplastic and neoplastic liver samples by two independent studies. Using multi-objective optimization, we extracted subnetworks that are simultaneously “guilt-by-association” with HCV proteins and enriched in proteins differentially expressed. These subnetworks contain established, recently proposed and novel candidate proteins for the regulation of the mechanisms of liver cells response to chronic HCV infection. PMID:25461596

  12. Expression and Immunogenicity of Two Recombinant Fusion Proteins Comprising Foot-and-Mouth Disease Virus Structural Protein VP1 and DC-SIGN-Binding Glycoproteins

    OpenAIRE

    Xinsheng Liu; Jianliang Lv; Yuzhen Fang; Peng Zhou; Yanzhen Lu; Li Pan; Zhongwang Zhang; Junwu Ma; Yongguang Zhang; Yonglu Wang

    2017-01-01

    Improving vaccine immunogenicity by targeting antigens to dendritic cells has recently emerged as a new design strategy in vaccine development. In this study, the VP1 gene of foot-and-mouth disease virus (FMDV) serotype A was fused with the gene encoding human immunodeficiency virus (HIV) membrane glycoprotein gp120 or C2-V3 domain of hepatitis C virus (HCV) envelope glycoprotein E2, both of which are DC-SIGN-binding glycoproteins. After codon optimization, the VP1 protein and the two recombi...

  13. Hepatitis C Virus NS5A Protein Down-regulates the Expression of Spindle Gene Aspm through PKR-p38 Signaling Pathway*S⃞

    Science.gov (United States)

    Wu, Shun-Chi; Chang, Shin C.; Wu, Hung-Yi; Liao, Pei-Ju; Chang, Ming-Fu

    2008-01-01

    Hepatitis C virus often causes persistent infection and hepatocellular carcinoma. Studies have demonstrated the roles of viral nonstructural protein 5A (NS5A) in the induction of chromosome aneuploidy, but the molecular mechanisms are not clear. In this study, hydrodynamics-based in vivo transfection was applied to a mouse system. Mouse hepatocytes that successfully expressed NS5A protein were isolated by laser capture microdissection. Gene expression profiles of the NS5A-expressing hepatocytes were examined by an Affymetrix oligonucleotide microarray system. Aspm (abnormal spindle-like, microcephaly associated), which encodes the mitotic spindle protein ASPM, was identified to be differentially expressed in the absence and the presence of NS5A. The down-regulation of Aspm mRNA and ASPM protein was confirmed by real time polymerase chain reaction and Western blot analysis, respectively, both in mouse model systems and in viral subgenomic replicon and in vitro transfection culturing systems. In addition, cultured cells that constitutively expressed NS5A protein showed G2/M cell cycle block and chromosome aneuploidy. Overexpression of ASPM relieved the G2/M cell cycle block. Furthermore, NS5A protein repressed the promoter activity of Aspm gene in a dose-dependent manner. The regulatory effect was abolished when amino acid substitutions P2209L, T2214A, and T2217G known to interrupt the NS5A-PKR interaction were introduced into the NS5A protein. This indicates that the down-regulation of Aspm expression is via the PKR-p38 signaling pathway. These results suggest that NS5A protein down-regulates the expression of the mitotic spindle protein ASPM and induces aberrant mitotic cell cycle associated with chromosome instability and hepatocellular carcinoma. PMID:18728014

  14. Hepatitis C virus NS5A protein down-regulates the expression of spindle gene Aspm through PKR-p38 signaling pathway.

    Science.gov (United States)

    Wu, Shun-Chi; Chang, Shin C; Wu, Hung-Yi; Liao, Pei-Ju; Chang, Ming-Fu

    2008-10-24

    Hepatitis C virus often causes persistent infection and hepatocellular carcinoma. Studies have demonstrated the roles of viral nonstructural protein 5A (NS5A) in the induction of chromosome aneuploidy, but the molecular mechanisms are not clear. In this study, hydrodynamics-based in vivo transfection was applied to a mouse system. Mouse hepatocytes that successfully expressed NS5A protein were isolated by laser capture microdissection. Gene expression profiles of the NS5A-expressing hepatocytes were examined by an Affymetrix oligonucleotide microarray system. Aspm (abnormal spindle-like, microcephaly associated), which encodes the mitotic spindle protein ASPM, was identified to be differentially expressed in the absence and the presence of NS5A. The down-regulation of Aspm mRNA and ASPM protein was confirmed by real time polymerase chain reaction and Western blot analysis, respectively, both in mouse model systems and in viral subgenomic replicon and in vitro transfection culturing systems. In addition, cultured cells that constitutively expressed NS5A protein showed G(2)/M cell cycle block and chromosome aneuploidy. Overexpression of ASPM relieved the G(2)/M cell cycle block. Furthermore, NS5A protein repressed the promoter activity of Aspm gene in a dose-dependent manner. The regulatory effect was abolished when amino acid substitutions P2209L, T2214A, and T2217G known to interrupt the NS5A-PKR interaction were introduced into the NS5A protein. This indicates that the down-regulation of Aspm expression is via the PKR-p38 signaling pathway. These results suggest that NS5A protein down-regulates the expression of the mitotic spindle protein ASPM and induces aberrant mitotic cell cycle associated with chromosome instability and hepatocellular carcinoma.

  15. Human papillomavirus L1 protein expressed in Escherichia coli self-assembles into virus-like particles that are highly immunogenic.

    Science.gov (United States)

    Chen, Yumei; Liu, Yunchao; Zhang, Gaiping; Wang, Aiping; Dong, Ziming; Qi, Yanhua; Wang, Jucai; Zhao, Baolei; Li, Ning; Jiang, Min

    2016-07-15

    HPV vaccines based on L1 virus-like particles (VLPs) provided a high degree of protection against HPVs infection. In this study, the codon optimized HPV16 L1 gene were sub-cloned into five procaryotic expression vectors (pET-28a, pET-32a, pGEX-4T-2, pE-sumo and pHSIE), and fused with different protein tags. No recombinant proteins were expressed in pET-28a-L1 and pHSIE-L1, and the proteins expressed by pET-32a-L1 plasmid with TRX-tag were in the form of inclusion body. Only SUMO-tagged and GST-tagged L1 proteins expressed by pE-Sumo-L1 or pGEX-4T-L1 were soluble. The yield of SUMO-L1 protein reached 260mg/L fermentation medium in shake flask. After SUMO tags were eliminated, a 90% purity of L1 proteins was generated by ion-exchange and Ni-NTA affinity chromatography. The purified HPV16 L1 protein self-assembled into virus-like particles (VLPs) and showed a haemagglutination activity. High titers specific and neutralizing antibodies were detected in HPV 16 L1VLPs vaccinated mice. Cytokines such as IFN-γ and IL-2 showed significant higher in VLPs vaccinated mice compared with negative control (p<0.05, p=0.055). Thus, the expression of recombinant HPV16 L1 VLPs in Escherichia coli was feasible, which could potentially be used for a VLP-based HPV vaccine. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. PSITE vectors for stable integration or transient expression of autofluorescent protein fusions in plants: probing Nicotiana benthamiana-virus interactions

    National Research Council Canada - National Science Library

    Chakrabarty, Romit; Banerjee, Rituparna; Chung, Sang-Min; Farman, Mark; Citovsky, Vitaly; Hogenhout, Saskia A; Tzfira, Tzvi; Goodin, Michael

    2007-01-01

    .... Here, we describe the pSITE family of plasmids, a new set of Agrobacterium binary vectors, suitable for the stable integration or transient expression of various autofluorescent protein fusions in plant cells...

  17. A vaccinia virus recombinant transcribing an alphavirus replicon and expressing alphavirus structural proteins leads to packaging of alphavirus infectious single cycle particles.

    Directory of Open Access Journals (Sweden)

    Juana M Sánchez-Puig

    Full Text Available Poxviruses and Alphaviruses constitute two promising viral vectors that have been used extensively as expression systems, or as vehicles for vaccine purposes. Poxviruses, like vaccinia virus (VV are well-established vaccine vectors having large insertion capacity, excellent stability, and ease of administration. In turn, replicons derived from Alphaviruses like Semliki Forest virus (SFV are potent protein expression and immunization vectors but stocks are difficult to produce and maintain. In an attempt to demonstrate the use of a Poxvirus as a means for the delivery of small vaccine vectors, we have constructed and characterized VV/SFV hybrid vectors. A SFV replicon cDNA was inserted in the VV genome and placed under the control of a VV early promoter. The replicon, transcribed from the VV genome as an early transcript, was functional, and thus capable of initiating its own replication and transcription. Further, we constructed a VV recombinant additionally expressing the SFV structural proteins under the control of a vaccinia synthetic early/late promoter. Infection with this recombinant produced concurrent transcription of the replicon and expression of SFV structural proteins, and led to the generation of replicon-containing SFV particles that were released to the medium and were able to infect additional cells. This combined VV/SFV system in a single virus allows the use of VV as a SFV delivery vehicle in vivo. The combination of two vectors, and the possibility of generating in vivo single-cycle, replicon containing alphavirus particles, may open new strategies in vaccine development or in the design of oncolytic viruses.

  18. Expression of Foot-and-Mouth Disease Virus Non-Structural Protein, 3D in Insect Cells and its Application in Detection of Anti-FMDV Antibodies

    OpenAIRE

    Kumar, Rakesh; M Hosamani; Sreenivasa, B. P.; Kotyal, Anil; Venkataramanan, R.

    2012-01-01

    Non-structural proteins (NSPs) based diagnostics are useful for large-scale sero-surveillance of foot-and-mouth disease (FMD) and to monitor viral activity as a follow up to the vaccination campaign in FMD endemic countries like India which aim at disease control through vaccination. These diagnostics are also handy in the serology of import/export of cloven-footed animals. In the present study, non-structural protein RNA polymerase (3D gene) of FMD virus (FMDV) was expressed using baculoviru...

  19. Upregulation of insulin-like growth factor binding protein 3 in astrocytes of transgenic mice that express Borna disease virus phosphoprotein.

    Science.gov (United States)

    Honda, Tomoyuki; Fujino, Kan; Okuzaki, Daisuke; Ohtaki, Naohiro; Matsumoto, Yusuke; Horie, Masayuki; Daito, Takuji; Itoh, Masayuki; Tomonaga, Keizo

    2011-05-01

    In a previous study, we demonstrated that transgenic mice that express Borna disease virus (BDV) phosphoprotein (P) in astrocytes show striking neurobehavioral abnormalities resembling those in BDV-infected animals. To understand the molecular disturbances induced by the expression of P in astrocytes, we performed microarray analysis with cultured astroglial cells transiently expressing P. We showed that expression of insulin-like growth factor binding protein 3 mRNA increases not only in P-expressing cultured cells but also in astrocytes from the cerebella of P transgenic mice (P-Tg). Furthermore, we demonstrated that insulin-like growth factor signaling is disturbed in the P-Tg cerebellum, a factor that might be involved in the increased vulnerability of Purkinje cell neurons in the brain.

  20. Differential regulation of hepatitis B virus core protein expression and genome replication by a small upstream open reading frame and naturally occurring mutations in the precore region.

    Science.gov (United States)

    Zong, Li; Qin, Yanli; Jia, Haodi; Ye, Lei; Wang, Yongxiang; Zhang, Jiming; Wands, Jack R; Tong, Shuping; Li, Jisu

    2017-05-01

    Hepatitis B virus (HBV) transcribes two subsets of 3.5-kb RNAs: precore RNA for hepatitis B e antigen (HBeAg) expression, and pregenomic RNA for core and P protein translation as well as genome replication. HBeAg expression could be prevented by mutations in the precore region, while an upstream open reading frame (uORF) has been proposed as a negative regulator of core protein translation. We employed replication competent HBV DNA constructs and transient transfection experiments in Huh7 cells to verify the uORF effect and to explore the alternative function of precore RNA. Optimized Kozak sequence for the uORF or extra ATG codons as present in some HBV genotypes reduced core protein expression. G1896A nonsense mutation promoted more efficient core protein expression than mutated precore ATG, while a +1 frameshift mutation was ineffective. In conclusion, various HBeAg-negative precore mutations and mutations affecting uORF differentially regulate core protein expression and genome replication. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Expression, purification, crystallization and preliminary X-ray analysis of a C-terminal fragment of the Epstein–Barr virus ZEBRA protein

    Energy Technology Data Exchange (ETDEWEB)

    Morand, Patrice [European Molecular Biology Laboratory, Grenoble Outstation, BP 181, 38042 Grenoble CEDEX 9 (France); Laboratoire de Virologie Moléculaire et Structurale, EA 2939, Université Joseph Fourier, Grenoble (France); Budayova-Spano, Monika [European Molecular Biology Laboratory, Grenoble Outstation, BP 181, 38042 Grenoble CEDEX 9 (France); Perrissin, Monique [Laboratoire de Virologie Moléculaire et Structurale, EA 2939, Université Joseph Fourier, Grenoble (France); Müller, Christoph W., E-mail: mueller@embl-grenoble.fr; Petosa, Carlo [European Molecular Biology Laboratory, Grenoble Outstation, BP 181, 38042 Grenoble CEDEX 9 (France)

    2006-03-01

    A C-terminal fragment of the Epstein–Barr virus lytic switch protein ZEBRA has been crystallized in complex with DNA. A C-terminal fragment of the Epstein–Barr virus immediate-early transcription factor ZEBRA has been expressed as a recombinant protein in Escherichia coli and purified to homogeneity. The fragment behaves as a dimer in solution, consistent with the presence of a basic region leucine-zipper (bZIP) domain. Crystals of the fragment in complex with a DNA duplex were grown by the hanging-drop vapour-diffusion technique using polyethylene glycol 4000 and magnesium acetate as crystallization agents. Crystals diffract to better than 2.5 Å resolution using synchrotron radiation (λ = 0.976 Å). Crystals belong to space group C2, with unit-cell parameters a = 94.2, b = 26.5, c = 98.1 Å, β = 103.9°.

  2. Large-scale analysis of protein expression changes in human keratinocytes immortalized by human papilloma virus type 16 E6 and E7 oncogenes

    Directory of Open Access Journals (Sweden)

    Arnouk Hilal

    2009-08-01

    Full Text Available Abstract Background Infection with high-risk type human papilloma viruses (HPVs is associated with cervical carcinomas and with a subset of head and neck squamous cell carcinomas. Viral E6 and E7 oncogenes cooperate to achieve cell immortalization by a mechanism that is not yet fully understood. Here, human keratinocytes were immortalized by long-term expression of HPV type 16 E6 or E7 oncoproteins, or both. Proteomic profiling was used to compare expression levels for 741 discrete protein features. Results Six replicate measurements were performed for each group using two-dimensional difference gel electrophoresis (2D-DIGE. The median within-group coefficient of variation was 19–21%. Significance of between-group differences was tested based on Significance Analysis of Microarray and fold change. Expression of 170 (23% of the protein features changed significantly in immortalized cells compared to primary keratinocytes. Most of these changes were qualitatively similar in cells immortalized by E6, E7, or E6/7 expression, indicating convergence on a common phenotype, but fifteen proteins (~2% were outliers in this regulatory pattern. Ten demonstrated opposite regulation in E6- and E7-expressing cells, including the cell cycle regulator p16INK4a; the carbohydrate binding protein Galectin-7; two differentially migrating forms of the intermediate filament protein Cytokeratin-7; HSPA1A (Hsp70-1; and five unidentified proteins. Five others had a pattern of expression that suggested cooperativity between the co-expressed oncoproteins. Two of these were identified as forms of the small heat shock protein HSPB1 (Hsp27. Conclusion This large-scale analysis provides a framework for understanding the cooperation between E6 and E7 oncoproteins in HPV-driven carcinogenesis.

  3. Stable expression of foot-and-mouth disease virus protein VP1 fused with cholera toxin B subunit in the potato (Solanum tuberosum).

    Science.gov (United States)

    He, Dong-Mei; Qian, Kai-Xian; Shen, Gui-Fang; Li, Yi-Nü; Zhang, Zhi-Fang; Su, Zhong-Liang; Shao, Hong-Bo

    2007-04-01

    The expression vector, pBI121CTBVP1, containing the fusion of the foot and mouth disease virus (FMDV) VP1 gene and the cholera toxin B subunit (CTB) gene was constructed by fused PCR and transferred into potato (Solanum tuberosum L.) by Agrobacterium-mediated transformation. Transformed plants were obtained by selecting on kanamycin-resistant medium strictly and regenerated. The transgenic plantlets were identified by PCR, Southern-blot and the production of fused protein was confirmed and quantified by Western-blot and ELISA assays. The results showed that the fused genes were expressed stablely under the control of specific-tuber patatin promoter. The expressed fused proteins have a certain degree of immunogenicity.

  4. Improved long-term expression from helper virus-free HSV-1 vectors packaged using combinations of mutated HSV-1 proteins that include the UL13 protein kinase and specific components of the VP16 transcriptional complex

    Directory of Open Access Journals (Sweden)

    Geller Alfred I

    2009-06-01

    Full Text Available Abstract Background Herpes Simplex Virus (HSV-1 gene expression is thought to shut off recombinant gene expression from HSV-1 vectors; however, in a helper virus-free HSV-1 vector system, a number of promoters support only short-term expression. These results raise the paradox that recombinant gene expression remains short-term even in the absence of almost all (~99% of the HSV-1 genome, HSV-1 genes, and HSV-1 gene expression. To resolve this paradox, we hypothesized that specific proteins in the HSV-1 virus particle shut off recombinant gene expression. In two earlier studies, we examined the effects on recombinant gene expression of packaging vectors using specific mutated HSV-1 proteins. We found that vectors packaged using mutated UL13 (a protein kinase, or VP16, or UL46 and/or UL47 (components of the VP16 transcriptional complex supported improved long-term expression, and vectors packaged using mutated UL46 and/or UL47 also supported improved gene transfer (numbers of cells at 4 days. These results suggested the hypothesis that specific proteins in the HSV-1 particle act by multiple pathways to reduce recombinant gene expression. To test this hypothesis, we examined combinations of mutated proteins that included both UL13 and specific components of the VP16 transcriptional complex. Results A HSV-1 vector containing a neuronal-specific promoter was packaged using specific combinations of mutated proteins, and the resulting vector stocks were tested in the rat striatum. For supporting long-term expression, the preferred combination of mutated HSV-1 proteins was mutated UL13, UL46, and UL47. Vectors packaged using this combination of mutated proteins supported a higher efficiency of gene transfer and high levels expression for 3 months, the longest time examined. Conclusion Vector particles containing this combination of mutated HSV-1 proteins improve recombinant gene expression. Implications of these results for strategies to further improve

  5. Improved long-term expression from helper virus-free HSV-1 vectors packaged using combinations of mutated HSV-1 proteins that include the UL13 protein kinase and specific components of the VP16 transcriptional complex.

    Science.gov (United States)

    Liu, Meng; Wang, Xiaodan; Geller, Alfred I

    2009-06-16

    Herpes Simplex Virus (HSV-1) gene expression is thought to shut off recombinant gene expression from HSV-1 vectors; however, in a helper virus-free HSV-1 vector system, a number of promoters support only short-term expression. These results raise the paradox that recombinant gene expression remains short-term even in the absence of almost all (approximately 99%) of the HSV-1 genome, HSV-1 genes, and HSV-1 gene expression. To resolve this paradox, we hypothesized that specific proteins in the HSV-1 virus particle shut off recombinant gene expression. In two earlier studies, we examined the effects on recombinant gene expression of packaging vectors using specific mutated HSV-1 proteins. We found that vectors packaged using mutated UL13 (a protein kinase), or VP16, or UL46 and/or UL47 (components of the VP16 transcriptional complex) supported improved long-term expression, and vectors packaged using mutated UL46 and/or UL47 also supported improved gene transfer (numbers of cells at 4 days). These results suggested the hypothesis that specific proteins in the HSV-1 particle act by multiple pathways to reduce recombinant gene expression. To test this hypothesis, we examined combinations of mutated proteins that included both UL13 and specific components of the VP16 transcriptional complex. A HSV-1 vector containing a neuronal-specific promoter was packaged using specific combinations of mutated proteins, and the resulting vector stocks were tested in the rat striatum. For supporting long-term expression, the preferred combination of mutated HSV-1 proteins was mutated UL13, UL46, and UL47. Vectors packaged using this combination of mutated proteins supported a higher efficiency of gene transfer and high levels expression for 3 months, the longest time examined. Vector particles containing this combination of mutated HSV-1 proteins improve recombinant gene expression. Implications of these results for strategies to further improve long-term expression are discussed

  6. Pichia pastoris-expressed dengue 2 envelope forms virus-like particles without pre-membrane protein and induces high titer neutralizing antibodies.

    Directory of Open Access Journals (Sweden)

    Shailendra Mani

    Full Text Available Dengue is a mosquito-borne viral disease with a global prevalence. It is caused by four closely-related dengue viruses (DENVs 1-4. A dengue vaccine that can protect against all four viruses is an unmet public health need. Live attenuated vaccine development efforts have encountered unexpected interactions between the vaccine viruses, raising safety concerns. This has emphasized the need to explore non-replicating dengue vaccine options. Virus-like particles (VLPs which can elicit robust immunity in the absence of infection offer potential promise for the development of non-replicating dengue vaccine alternatives. We have used the methylotrophic yeast Pichia pastoris to develop DENV envelope (E protein-based VLPs. We designed a synthetic codon-optimized gene, encoding the N-terminal 395 amino acid residues of the DENV-2 E protein. It also included 5' pre-membrane-derived signal peptide-encoding sequences to ensure proper translational processing, and 3' 6× His tag-encoding sequences to facilitate purification of the expressed protein. This gene was integrated into the genome of P. pastoris host and expressed under the alcohol oxidase 1 promoter by methanol induction. Recombinant DENV-2 protein, which was present in the insoluble membrane fraction, was extracted and purified using Ni(2+-affinity chromatography under denaturing conditions. Amino terminal sequencing and detection of glycosylation indicated that DENV-2 E had undergone proper post-translational processing. Electron microscopy revealed the presence of discrete VLPs in the purified protein preparation after dialysis. The E protein present in these VLPs was recognized by two different conformation-sensitive monoclonal antibodies. Low doses of DENV-2 E VLPs formulated in alum were immunogenic in inbred and outbred mice eliciting virus neutralizing titers >1,1200 in flow cytometry based assays and protected AG129 mice against lethal challenge (p<0.05. The formation of immunogenic DENV-2 E

  7. Genomic Methylation Inhibits Expression of Hepatitis B Virus Envelope Protein in Transgenic Mice: A Non-Infectious Mouse Model to Study Silencing of HBV Surface Antigen Genes.

    Science.gov (United States)

    Graumann, Franziska; Churin, Yuri; Tschuschner, Annette; Reifenberg, Kurt; Glebe, Dieter; Roderfeld, Martin; Roeb, Elke

    2015-01-01

    The Hepatitis B virus genome persists in the nucleus of virus infected hepatocytes where it serves as template for viral mRNA synthesis. Epigenetic modifications, including methylation of the CpG islands contribute to the regulation of viral gene expression. The present study investigates the effects of spontaneous age dependent loss of hepatitis B surface protein- (HBs) expression due to HBV-genome specific methylation as well as its proximate positive effects in HBs transgenic mice. Liver and serum of HBs transgenic mice aged 5-33 weeks were analyzed by Western blot, immunohistochemistry, serum analysis, PCR, and qRT-PCR. From the third month of age hepatic loss of HBs was observed in 20% of transgenic mice. The size of HBs-free area and the relative number of animals with these effects increased with age and struck about 55% of animals aged 33 weeks. Loss of HBs-expression was strongly correlated with amelioration of serum parameters ALT and AST. In addition lower HBs-expression went on with decreased ER-stress. The loss of surface protein expression started on transcriptional level and appeared to be regulated epigenetically by DNA methylation. The amount of the HBs-expression correlated negatively with methylation of HBV DNA in the mouse genome. Our data suggest that methylation of specific CpG sites controls gene expression even in HBs-transgenic mice with truncated HBV genome. More important, the loss of HBs expression and intracellular aggregation ameliorated cell stress and liver integrity. Thus, targeted modulation of HBs expression may offer new therapeutic approaches. Furthermore, HBs-transgenic mice depict a non-infectious mouse model to study one possible mechanism of HBs gene silencing by hypermethylation.

  8. Protein expression-yeast.

    Science.gov (United States)

    Nielsen, Klaus H

    2014-01-01

    Yeast is an excellent system for the expression of recombinant eukaryotic proteins. Both endogenous and heterologous proteins can be overexpressed in yeast (Phan et al., 2001; Ton and Rao, 2004). Because yeast is easy to manipulate genetically, a strain can be optimized for the expression of a specific protein. Many eukaryotic proteins contain posttranslational modifications that can be performed in yeast but not in bacterial expression systems. In comparison with mammalian cell culture expression systems, growing yeast is both faster and less expensive, and large-scale cultures can be performed using fermentation. While several different yeast expression systems exist, this chapter focuses on the budding yeast Saccharomyces cerevisiae and will briefly describe some options to consider when selecting vectors and tags to be used for protein expression. Throughout this chapter, the expression and purification of yeast eIF3 is shown as an example alongside a general scheme outline. © 2014 Elsevier Inc. All rights reserved.

  9. Oral immunization with transgenic rice seeds expressing VP2 protein of infectious bursal disease virus induces protective immune responses in chickens.

    Science.gov (United States)

    Wu, Jianxiang; Yu, Lian; Li, Long; Hu, Jinqiang; Zhou, Jiyong; Zhou, Xueping

    2007-09-01

    The expression of infectious bursal disease virus (IBDV) host-protective immunogen VP2 protein in rice seeds, its immunogenicity and protective capability in chickens were investigated. The VP2 cDNA of IBDV strain ZJ2000 was cloned downstream of the Gt1 promoter of the rice glutelin GluA-2 gene in the binary expression vector, pCambia1301-Gt1. Agrobacterium tumefaciens containing the recombinant vector was used to transform rice embryogenic calli, and 121 transgenic lines were obtained and grown to maturity in a greenhouse. The expression level of VP2 protein in transgenic rice seeds varied from 0.678% to 4.521% microg/mg of the total soluble seed protein. Specific pathogen-free chickens orally vaccinated with transgenic rice seeds expressing VP2 protein produced neutralizing antibodies against IBDV and were protected when challenged with a highly virulent IBDV strain, BC6/85. These results demonstrate that transgenic rice seeds expressing IBDV VP2 can be used as an effective, safe and inexpensive vaccine against IBDV.

  10. Goose parvovirus structural proteins expressed by recombinant baculoviruses self-assemble into virus-like particles with strong immunogenicity in goose.

    Science.gov (United States)

    Ju, Huanyu; Wei, Na; Wang, Qian; Wang, Chunyuan; Jing, Zhiqiang; Guo, Lu; Liu, Dapeng; Gao, Mingchun; Ma, Bo; Wang, Junwei

    2011-05-27

    Goose parvovirus (GPV), a small non-enveloped ssDNA virus, can cause Derzsy's disease, and three capsid proteins of VP1, VP2, and VP3 are encoded by an overlapping nucleotide sequence. However, little is known on whether recombinant viral proteins (VPs) could spontaneously assemble into virus-like particles (VLPs) in insect cells and whether these VLPs could retain their immunoreactivity and immunogenicity in susceptible geese. To address these issues, genes for these GPV VPs were amplified by PCR, and the recombinant VPs proteins were expressed in insect cells using a baculovirus expression system for the characterization of their structures, immunoreactivity, and immunogenicity. The rVP1, rVP2, and rVP3 expressed in Sf9 cells were detected by anti-GPV sera, anti-VP3 sera, and anti-His antibodies, respectively. Electron microscopy revealed that these rVPs spontaneously assembled into VLPs in insect cells, similar to that of the purified wild-type GPV virions. In addition, vaccination with individual types of VLPs, particularly with the rVP2-VLPs, induced higher titers of antibodies and neutralized different strains of GPVs in primary goose and duck embryo fibroblast cells in vitro. These data indicated that these VLPs retained immunoreactivity and had strong immunogenicity in susceptible geese. Therefore, our findings may provide a framework for development of new vaccines for the prevention of Derzsy's disease and vehicles for the delivery of drugs. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Cell-free expression, purification, and membrane reconstitution for NMR studies of the nonstructural protein 4B from hepatitis C virus

    Energy Technology Data Exchange (ETDEWEB)

    Fogeron, Marie-Laure [Université de Lyon, Institut de Biologie et Chimie des Protéines, Bases Moléculaires et Structurales des Systèmes Infectieux, Labex Ecofect, UMR 5086 CNRS (France); Jirasko, Vlastimil; Penzel, Susanne [ETH Zurich, Physical Chemistry (Switzerland); Paul, David [Heidelberg University, Department of Infectious Diseases, Molecular Virology (Germany); Montserret, Roland; Danis, Clément; Lacabanne, Denis; Badillo, Aurélie [Université de Lyon, Institut de Biologie et Chimie des Protéines, Bases Moléculaires et Structurales des Systèmes Infectieux, Labex Ecofect, UMR 5086 CNRS (France); Gouttenoire, Jérôme; Moradpour, Darius [University of Lausanne, Division of Gastroenterology and Hepatology, Centre Hospitalier Universitaire Vaudois (Switzerland); Bartenschlager, Ralf [Heidelberg University, Department of Infectious Diseases, Molecular Virology (Germany); Penin, François [Université de Lyon, Institut de Biologie et Chimie des Protéines, Bases Moléculaires et Structurales des Systèmes Infectieux, Labex Ecofect, UMR 5086 CNRS (France); Meier, Beat H., E-mail: beme@ethz.ch [ETH Zurich, Physical Chemistry (Switzerland); and others

    2016-06-15

    We describe the expression of the hepatitis C virus nonstructural protein 4B (NS4B), which is an integral membrane protein, in a wheat germ cell-free system, the subsequent purification and characterization of NS4B and its insertion into proteoliposomes in amounts sufficient for multidimensional solid-state NMR spectroscopy. First spectra of the isotopically [{sup 2}H,{sup 13}C,{sup 15}N]-labeled protein are shown to yield narrow {sup 13}C resonance lines and a proper, predominantly α-helical fold. Clean residue-selective leucine, isoleucine and threonine-labeling is demonstrated. These results evidence the suitability of the wheat germ-produced integral membrane protein NS4B for solid-state NMR. Still, the proton linewidth under fast magic angle spinning is broader than expected for a perfect sample and possible causes are discussed.

  12. Elicitation of strong immune responses by a DNA vaccine expressing a secreted form of hepatitis C virus envelope protein E2 in murine and porcine animal models

    DEFF Research Database (Denmark)

    Li, Yiping; Kang, H.N.; Babiuk, L.A.

    2006-01-01

    AIM: To characterize the immunogenicity of a hepatitis C virus (HCV) E2 DNA vaccine alone or with a protein vaccine boost in murine and porcine animal models. METHODS: A DNA vaccine expressing a secreted form of HCV E2 protein was constructed and used to vaccinate mice and piglets with or without...... boosting with a recombinant E2 protein vaccine formulated with CpG ODN and 10% Emulsigen. The immunogenicity of HCV E2 vaccines was analyzed by ELISA for antibody responses, MTT assay for lymphocyte proliferation, ELISPOT for the number of interferon-gamma secreting cells, and cytotoxic T lymphocyte assays....... RESULTS: Intradermal injection of E2 DNA vaccine induced strong Th1-like immune responses in mice. In piglets, E2 DNA vaccine elicited moderate and more balanced immune responses. A DNA vaccine prime and protein boost vaccination, strategy induced significantly higher E2-specific antibody levels...

  13. Isolation of highly purified, functional carboxy-terminally truncated hepatitis B virus middle surface protein activators from eucaryotic expression systems.

    Science.gov (United States)

    Hildt, E; Urban, S; Eckerskorn, C; Hofschneider, P H

    1996-09-01

    Carboxy-terminally truncated hepatitis B virus (HBV) middle surface proteins (MHBst) show a transcriptional activator function. Two different subtypes of MHBst activators can be distinguished: an ER-localized type, represented here by MHBst76 (truncated at amino acid 76), and a cytosol-localized type, represented here by MHBst63. To characterize the MHBst activator on the protein level and to analyze posttranslational modifications, we established recombinant baculoviruses encoding for fusion proteins of MHBst76 or MHBst63 and of an amino terminal hexa-his tag. Both proteins could be obtained in high purity by affinity chromatography using Ni-nitrilo-tri-acetate agarose. In addition, 6H-MHBst76 was also isolated from transiently transfected HepG2 cells. Both the Spodoptera frugiperda (Sf9) cell-derived and the HepG2 cell-derived MHBst proteins were found to be unglycosylated. A detailed analysis of Sf9 cell-derived 6H-MHFBst76 by electrospray-ionization mass spectrometry showed that a fraction of this protein is N-terminally acetylated and phosphorylated or sulfated. Electric-field-mediated transfer of the highly purified proteins into reporter cells demonstrated that the isolated proteins are functional transcriptional activators. These experiments further showed that Sf9 cell-derived and HepG2 cell-derived 6H-MHBst do not differ in their functionality. This system allowed production and purification of functional 6H-MHBst in amounts sufficient enough to allow a further detailed analysis of MHBst activators on the protein level.

  14. Oral Delivery of a Novel Attenuated Salmonella Vaccine Expressing Influenza A Virus Proteins Protects Mice against H5N1 and H1N1 Viral Infection.

    Directory of Open Access Journals (Sweden)

    Zenglin Pei

    Full Text Available Attenuated strains of invasive enteric bacteria, such as Salmonella, represent promising gene delivery agents for nucleic acid-based vaccines as they can be administrated orally. In this study, we constructed a novel attenuated strain of Salmonella for the delivery and expression of the hemagglutinin (HA and neuraminidase (NA of a highly pathogenic H5N1 influenza virus. We showed that the constructed Salmonella strain exhibited efficient gene transfer activity for HA and NA expression and little cytotoxicity and pathogenicity in mice. Using BALB/c mice as the model, we evaluated the immune responses and protection induced by the constructed Salmonella-based vaccine. Our study showed that the Salmonella-based vaccine induced significant production of anti-HA serum IgG and mucosal IgA, and of anti-HA interferon-γ producing T cells in orally vaccinated mice. Furthermore, mice orally vaccinated with the Salmonella vaccine expressing viral HA and NA proteins were completely protected from lethal challenge of highly pathogenic H5N1 as well as H1N1 influenza viruses while none of the animals treated with the Salmonella vaccine carrying the empty expression vector with no viral antigen expression was protected. These results suggest that the Salmonella-based vaccine elicits strong antigen-specific humoral and cellular immune responses and provides effective immune protection against multiple strains of influenza viruses. Furthermore, our study demonstrates the feasibility of developing novel attenuated Salmonella strains as new oral vaccine vectors against influenza viruses.

  15. West nile virus-induced activation of mammalian target of rapamycin complex 1 supports viral growth and viral protein expression.

    Science.gov (United States)

    Shives, Katherine D; Beatman, Erica L; Chamanian, Mastooreh; O'Brien, Caitlin; Hobson-Peters, Jody; Beckham, J David

    2014-08-01

    Since its introduction in New York City, NY, in 1999, West Nile virus (WNV) has spread to all 48 contiguous states of the United States and is now the leading cause of epidemic encephalitis in North America. As a member of the family Flaviviridae, WNV is part of a group of clinically important human pathogens, including dengue virus and Japanese encephalitis virus. The members of this family of positive-sense, single-stranded RNA viruses have limited coding capacity and are therefore obligated to co-opt a significant amount of cellular factors to translate their genomes effectively. Our previous work has shown that WNV growth was independent of macroautophagy activation, but the role of the evolutionarily conserved mammalian target of rapamycin (mTOR) pathway during WNV infection was not well understood. mTOR is a serine/threonine kinase that acts as a central cellular censor of nutrient status and exercises control of vital anabolic and catabolic cellular responses such as protein synthesis and autophagy, respectively. We now show that WNV activates mTOR and cognate downstream activators of cap-dependent protein synthesis at early time points postinfection and that pharmacologic inhibition of mTOR (KU0063794) significantly reduced WNV growth. We used an inducible Raptor and Rictor knockout mouse embryonic fibroblast (MEF) system to further define the role of mTOR complexes 1 and 2 in WNV growth and viral protein synthesis. Following inducible genetic knockout of the major mTOR cofactors raptor (TOR complex 1 [TORC1]) and rictor (TORC2), we now show that TORC1 supports flavivirus protein synthesis via cap-dependent protein synthesis pathways and supports subsequent WNV growth. Since its introduction in New York City, NY, in 1999, West Nile virus (WNV) has spread to all 48 contiguous states in the United States and is now the leading cause of epidemic encephalitis in North America. Currently, the mechanism by which flaviviruses such as WNV translate their genomes in

  16. Induction of antigen-specific immune responses in mice by recombinant baculovirus expressing premembrane and envelope proteins of West Nile virus

    Directory of Open Access Journals (Sweden)

    Zhu Bibo

    2012-07-01

    Full Text Available Abstract Background West Nile Virus (WNV is an emerging arthropod-born flavivirus with increasing distribution worldwide that is responsible for a large proportion of viral encephalitis in humans and horses. Given that there are no effective antiviral drugs available for treatment of the disease, efforts have been directed to develop vaccines to prevent WNV infection. Recently baculovirus has emerged as a novel and attractive gene delivery vehicle for mammalian cells. Results In the present study, recombinant baculoviruses expressing WNV premembrane (prM and envelope (E proteins under the cytomegalovirus (CMV promoter with or without vesicular stomatitis virus glycoprotein (VSV/G were constructed. The recombinant baculoviruses designated Bac-G-prM/E and Bac-prM/E, efficiently express E protein in mammalian cells. Intramuscular injection of the two recombinant baculoviruses (at doses of 108 or 109 PFU/mouse induced the production of WNV-specific antibodies, neutralizing antibodies as well as gamma interferon (IFN-γ in a dose-dependent pattern. Interestingly, the recombinant baculovirus Bac-G-prM/E was found to be a more efficient immunogen than Bac-prM/E to elicit a robust immune response upon intramuscular injection. In addition, inoculation of baculovirus resulted in the secretion of inflammatory cytokines, such as TNF-α, IL-2 and IL-6. Conclusions These recombinant baculoviruses are capable of eliciting robust humoral and cellular immune responses in mice, and may be considered as novel vaccine candidates for West Nile Virus.

  17. Hepatitis E virus ORF2 protein over-expressed by baculovirus in hepatoma cells, efficiently encapsidates and transmits the viral RNA to naïve cells

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    Emerson Suzanne U

    2011-04-01

    Full Text Available Abstract A recombinant baculovirus(vBacORF2 that expressed the full-length ORF2 capsid protein of a genotype 1 strain of hepatitis E virus(HEV was constructed. Transduction of S10-3 human hepatoma cells with this baculovirus led to large amounts of ORF2 protein production in ~50% of the cells as determined by immune fluorescence microscopy. The majority of the ORF2 protein detected by Western blot was 72 kDa, the size expected for the full-length protein. To determine if the exogenously-supplied ORF2 protein could transencapsidate viral genomes, S10-3 cell cultures that had been transfected the previous day with an HEV replicon of genotype 1 that contained the gene for green fluorescent protein(GFP, in place of that for ORF2 protein, were transduced with the vBacORF2 virus. Cell lysates were prepared 5 days later and tested for the ability to deliver the GFP gene to HepG2/C3A cells, another human hepatoma cell line. FACS analysis indicated that lysates from cell cultures receiving only the GFP replicon were incapable of introducing the replicon into the HepG2/C3A cells whereas ~2% of the HepG2/C3A cells that received lysate from cultures that had received both the replicon and the baculovirus produced GFP. Therefore, the baculovirus-expressed ORF2 protein was able to trans-encapsidate the viral replicon and form a particle that could infect naïve HepG2/C3A cells. This ex vivo RNA packaging system should be useful for studying many aspects of HEV molecular biology.

  18. The K186E Amino Acid Substitution in the Canine Influenza Virus H3N8 NS1 Protein Restores Its Ability To Inhibit Host Gene Expression.

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    Nogales, Aitor; Chauché, Caroline; DeDiego, Marta L; Topham, David J; Parrish, Colin R; Murcia, Pablo R; Martínez-Sobrido, Luis

    2017-11-15

    Canine influenza viruses (CIVs) are the causative agents of canine influenza, a contagious respiratory disease in dogs, and include the equine-origin H3N8 and the avian-origin H3N2 viruses. Influenza A virus (IAV) nonstructural protein 1 (NS1) is a virulence factor essential for counteracting the innate immune response. Here, we evaluated the ability of H3N8 CIV NS1 to inhibit host innate immune responses. We found that H3N8 CIV NS1 was able to efficiently counteract interferon (IFN) responses but was unable to block general gene expression in human or canine cells. Such ability was restored by a single amino acid substitution in position 186 (K186E) that resulted in NS1 binding to the 30-kDa subunit of the cleavage and polyadenylation specificity factor (CPSF30), a cellular protein involved in pre-mRNA processing. We also examined the frequency distribution of K186 and E186 among H3N8 CIVs and equine influenza viruses (EIVs), the ancestors of H3N8 CIV, and experimentally determined the impact of amino acid 186 in the ability of different CIV and EIV NS1s to inhibit general gene expression. In all cases, the presence of E186 was responsible for the control of host gene expression. In contrast, the NS1 protein of H3N2 CIV harbors E186 and blocks general gene expression in canine cells. Altogether, our results confirm previous studies on the strain-dependent ability of NS1 to block general gene expression. Moreover, the observed polymorphism on amino acid 186 between H3N8 and H3N2 CIVs might be the result of adaptive changes acquired during long-term circulation of avian-origin IAVs in mammals.IMPORTANCE Canine influenza is a respiratory disease of dogs caused by two CIV subtypes, the H3N8 and H3N2 viruses, of equine and avian origins, respectively. Influenza NS1 is the main viral factor responsible for the control of host innate immune responses, and changes in NS1 can play an important role in host adaptation. Here we assessed the ability of H3N8 CIV NS1 to inhibit

  19. Human T cell leukaemia virus type 2 tax protein mediates CC-chemokine expression in peripheral blood mononuclear cells via the nuclear factor kappa B canonical pathway

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    Barrios, C S; Castillo, L; Zhi, H; Giam, C-Z; Beilke, M A

    2014-01-01

    Retroviral co-infections with human immunodeficiency virus type-1 (HIV-1) and human T cell leukaemia virus type 1 (HTLV-1) or type 2 (HTLV-2) are prevalent in many areas worldwide. It has been observed that HIV-1/HTLV-2 co-infections are associated with slower rates of CD4+ T cell decline and delayed progression to AIDS. This immunological benefit has been linked to the ability of Tax2, the transcriptional activating protein of HTLV-2, to induce the expression of macrophage inflammatory protein (MIP)-1α/CCL3, MIP-1β/CCL4 and regulated upon activation normal T cell expressed and secreted (RANTES)/CCL5 and to down-regulate the expression of the CCR5 co-receptor in peripheral blood mononuclear cells (PBMCs). This study aimed to assess the role of Tax2-mediated activation of the nuclear factor kappa B (NF-κB) signalling pathway on the production of the anti-viral CC-chemokines MIP-1α, MIP-1β and RANTES. Recombinant Tax1 and Tax2 proteins, or proteins expressed via adenoviral vectors used to infect cells, were tested for their ability to activate the NF-κB pathway in cultured PBMCs in the presence or absence of NF-κB pathway inhibitors. Results showed a significant release of MIP-1α, MIP-1β and RANTES by PBMCs after the activation of p65/RelA and p50. The secretion of these CC-chemokines was significantly reduced (P Tax2 protein may promote innate anti-viral immune responses through the activation of the canonical NF-κB pathway. PMID:24116893

  20. Dengue virus induces expression of CXC chemokine ligand 10/IFN-gamma-inducible protein 10, which competitively inhibits viral binding to cell surface heparan sulfate.

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    Chen, Jia-Perng; Lu, Hsin-Lin; Lai, Szu-Liang; Campanella, Gabriele S; Sung, Jui-Ming; Lu, Mei-Yi; Wu-Hsieh, Betty A; Lin, Yi-Ling; Lane, Thomas E; Luster, Andrew D; Liao, Fang

    2006-09-01

    Dengue virus is an arthropod-borne flavivirus that causes a mild febrile illness, dengue fever, or a potentially fatal syndrome, dengue hemorrhagic fever/dengue shock syndrome. Chemokines primarily orchestrate leukocyte recruitment to the areas of viral infection, which makes them critical mediators of immune and inflammatory responses. In the present study, we investigated the induction and function of chemokines in mice early after infection with dengue virus in vivo. We found that CXCL10/IFN-gamma-inducible protein 10 (IP-10) expression was rapidly and transiently induced in liver following infection. The expressed CXCL10/IP-10 likely mediates the recruitment of activated NK cells, given that anti-CXCL10/IP-10-treated mice showed diminished NK cell infiltration and reduced hepatic expression of effector molecules in activated NK cells after dengue virus infection. Of particular interest, we found that CXCL10/IP-10 also was able to inhibit viral binding to target cells in vitro. Further investigation revealed that various CXCL10/IP-10 mutants, in which the residues that mediate the interaction between the chemokine and heparan sulfate were substituted, failed to exert the inhibitory effect on dengue binding, which suggests that CXCL10/IP-10 competes with dengue virus for binding to heparan sulfate on the cell surface. Moreover, subsequent plaque assays showed that this inhibition of dengue binding blocked viral uptake and replication. The inhibitory effect of CXCL10/IP-10 on the binding of dengue virus to cells may represent a novel contribution of this chemokine to the host defense against viral infection.

  1. Suppression of RNA silencing by a plant DNA virus satellite requires a host calmodulin-like protein to repress RDR6 expression.

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    Fangfang Li

    2014-02-01

    Full Text Available In plants, RNA silencing plays a key role in antiviral defense. To counteract host defense, plant viruses encode viral suppressors of RNA silencing (VSRs that target different effector molecules in the RNA silencing pathway. Evidence has shown that plants also encode endogenous suppressors of RNA silencing (ESRs that function in proper regulation of RNA silencing. The possibility that these cellular proteins can be subverted by viruses to thwart host defense is intriguing but has not been fully explored. Here we report that the Nicotiana benthamiana calmodulin-like protein Nbrgs-CaM is required for the functions of the VSR βC1, the sole protein encoded by the DNA satellite associated with the geminivirus Tomato yellow leaf curl China virus (TYLCCNV. Nbrgs-CaM expression is up-regulated by the βC1. Transgenic plants over-expressing Nbrgs-CaM displayed developmental abnormities reminiscent of βC1-associated morphological alterations. Nbrgs-CaM suppressed RNA silencing in an Agrobacterium infiltration assay and, when over-expressed, blocked TYLCCNV-induced gene silencing. Genetic evidence showed that Nbrgs-CaM mediated the βC1 functions in silencing suppression and symptom modulation, and was required for efficient virus infection. Moreover, the tobacco and tomato orthologs of Nbrgs-CaM also possessed ESR activity, and were induced by betasatellite to promote virus infection in these Solanaceae hosts. We further demonstrated that βC1-induced Nbrgs-CaM suppressed the production of secondary siRNAs, likely through repressing RNA-DEPENDENT RNA POLYMERASE 6 (RDR6 expression. RDR6-deficient N. benthamiana plants were defective in antiviral response and were hypersensitive to TYLCCNV infection. More significantly, TYLCCNV could overcome host range restrictions to infect Arabidopsis thaliana when the plants carried a RDR6 mutation. These findings demonstrate a distinct mechanism of VSR for suppressing PTGS through usurpation of a host ESR, and

  2. Lentiviral Gag assembly analyzed through the functional characterization of chimeric simian immunodeficiency viruses expressing different domains of the feline immunodeficiency virus capsid protein.

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    María J Esteva

    Full Text Available To gain insight into the functional relationship between the capsid (CA domains of the Gag polyproteins of simian and feline immunodeficiency viruses (SIV and FIV, respectively, we constructed chimeric SIVs in which the CA-coding region was partially or totally replaced by the equivalent region of the FIV CA. The phenotypic characterization of the chimeras allowed us to group them into three categories: the chimeric viruses that, while being assembly-competent, exhibit a virion-associated unstable FIV CA; a second group represented only by the chimeric SIV carrying the N-terminal domain (NTD of the FIV CA which proved to be assembly-defective; and a third group constituted by the chimeric viruses that produce virions exhibiting a mature and stable FIV CA protein, and which incorporate the envelope glycoprotein and contain wild-type levels of viral genome RNA and reverse transcriptase. Further analysis of the latter group of chimeric SIVs demonstrated that they are non-infectious due to a post-entry impairment, such as uncoating of the viral core, reverse transcription or nuclear import of the preintegration complex. Furthermore, we show here that the carboxyl-terminus domain (CTD of the FIV CA has an intrinsic ability to dimerize in vitro and form high-molecular-weight oligomers, which, together with our finding that the FIV CA-CTD is sufficient to confer assembly competence to the resulting chimeric SIV Gag polyprotein, provides evidence that the CA-CTD exhibits more functional plasticity than the CA-NTD. Taken together, our results provide relevant information on the biological relationship between the CA proteins of primate and nonprimate lentiviruses.

  3. A stable cytosolic expression of VH antibody fragment directed against PVY NIa protein in transgenic potato plant confers partial protection against the virus.

    Science.gov (United States)

    Bouaziz, Donia; Ayadi, Malika; Bidani, Amira; Rouis, Souad; Nouri-Ellouz, Oumèma; Jellouli, Raïda; Drira, Noureddine; Gargouri-Bouzid, Radhia

    2009-04-01

    The expression of recombinant antibodies in transgenic plants has been proved to be an efficient approach for large-scale production. However, the stability of these molecules and their accumulation level depend on their molecular properties and cellular targeting. The expression of single-domain antibody fragment (VH) can be advantageous since it offers small length, high expression, solubility and stability. It can therefore be preferred to other antibody derivatives avoiding the expression difficulties related to immunoglobulin domain folding via the formation of disulfide bridge. This report describes the production of transgenic potato plants expressing a VH antibody directed against the NIa protease of potato virus Y. The antibody was driven by the constitutive CaMV 35S RNA promoter. The expression cassette was transferred into potato plants via Agrobacterium tumefaciens mediated transformation. All transgenic lines showed detectable levels of VH protein confirming the efficient translation and stability of this protein. The cellular localisation of the VH antibody was investigated. Transgenic and control plants were transferred in the greenhouse and mechanically inoculated by PVY(o) suspension. Some of the transgenic lines showed delayed symptoms at the first period post inoculation and then displayed a recovery phenomenon while the virions were still detected in the leaves. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

  4. Development of a new vector using Soybean yellow common mosaic virus for gene function study or heterologous protein expression in soybeans.

    Science.gov (United States)

    Lim, Seungmo; Nam, Moon; Kim, Kil Hyun; Lee, Su-Heon; Moon, Jung-Kyung; Lim, Hyoun-Sub; Choung, Myoung-Gun; Kim, Sang-Mok; Moon, Jae Sun

    2016-02-01

    A new vector using Soybean yellow common mosaic virus (SYCMV) was constructed for gene function study or heterologous protein expression in soybeans. The in vitro transcript with a 5' cap analog m7GpppG from an SYCMV full-length infectious vector driven by a T7 promoter infected soybeans (pSYCMVT7-full). The symptoms observed in the soybeans infected with either the sap from SYCMV-infected leaves or pSYCMVT7-full were indistinguishable, suggesting that the vector exhibits equivalent biological activity as the virus itself. To utilize the vector further, a DNA-based vector driven by the Cauliflower mosaic virus (CaMV) 35S promoter was constructed. The complete sequence of the SYCMV genome was inserted into a binary vector flanked by a CaMV 35S promoter at the 5' terminus of the SYCMV genome and a cis-cleaving ribozyme sequence followed by a nopaline synthase terminator at the 3' terminus of the SYCMV genome (pSYCMV-full). The SYCMV-derived vector was tested for use as a virus-induced gene silencing (VIGS) vector for the functional analysis of soybean genes. VIGS constructs containing either a fragment of the Phytoene desaturase (PDS) gene (pSYCMV-PDS1) or a fragment of the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (RbcS) gene (pSYCMV-RbcS2) were constructed. Plants infiltrated with each vector using the Agrobacterium-mediated inoculation method exhibited distinct symptoms, such as photo-bleaching in plants infiltrated with pSYCMV-PDS1 and yellow or pale green coloring in plants infiltrated with pSYCMV-RbcS2. In addition, down-regulation of the transcripts of the two target genes was confirmed via northern blot analysis. Particle bombardment and direct plasmid DNA rubbing were also confirmed as alternative inoculation methods. To determine if the SYCMV vector can be used for the expression of heterologous proteins in soybean plants, the vector encoding amino acids 135-160 of VP1 of Foot-and-mouth disease virus (FMDV) serotype O1 Campos (O1C

  5. Kaposi's sarcoma-associated herpesvirus noncoding polyadenylated nuclear RNA interacts with virus- and host cell-encoded proteins and suppresses expression of genes involved in immune modulation.

    Science.gov (United States)

    Rossetto, Cyprian C; Pari, Gregory S

    2011-12-01

    During lytic infection, Kaposi's sarcoma-associated herpesvirus (KSHV) expresses a polyadenylated nuclear RNA (PAN RNA). This noncoding RNA (ncRNA) is localized to the nucleus and is the most abundant viral RNA during lytic infection; however, to date, the role of PAN RNA in the virus life cycle is unknown. Many examples exist where ncRNAs have a defined key regulatory function controlling gene expression by various mechanisms. Our goal for this study was to identify putative binding partners for PAN RNA in an effort to elucidate a possible function for the transcript in KSHV infection. We employed an in vitro affinity protocol where PAN RNA was used as bait for factors present in BCBL-1 cell nuclear extract to show that PAN RNA interacts with several virus- and host cell-encoded factors, including histones H1 and H2A, mitochondrial and cellular single-stranded binding proteins (SSBPs), and interferon regulatory factor 4 (IRF4). RNA chromatin immunoprecipitation (ChIP) assays confirmed that PAN RNA interacted with these factors in the infected cell environment. A luciferase reporter assay showed that PAN RNA expression interfered with the ability of IRF4/PU.1 to activate the interleukin-4 (IL-4) promoter, strongly suggesting a role for PAN RNA in immune modulation. Since the proteomic screen and functional data suggested a role in immune responses, we investigated if constitutive PAN RNA expression could affect other genes involved in immune responses. PAN RNA expression decreased expression of gamma interferon, interleukin-18, alpha interferon 16, and RNase L. These data strongly suggest that PAN RNA interacts with viral and cellular proteins and can function as an immune modulator.

  6. Conditional Human Immunodeficiency Virus Transactivator of Transcription Protein Expression Induces Depression-like Effects and Oxidative Stress.

    Science.gov (United States)

    McLaughlin, Jay P; Paris, Jason J; Mintzopoulos, Dionyssios; Hymel, Kristen A; Kim, Jae K; Cirino, Thomas J; Gillis, Timothy E; Eans, Shainnel O; Vitaliano, Gordana D; Medina, Jessica M; Krapf, Richard C; Stacy, Heather M; Kaufman, Marc J

    2017-10-01

    The prevalence of major depression in those with HIV/AIDS is substantially higher than in the general population. Mechanisms underlying this comorbidity are poorly understood. HIV-transactivator of transcription (Tat) protein, produced and excreted by HIV, could be involved. We determined whether conditional Tat protein expression in mice is sufficient to induce depression-like behaviors and oxidative stress. Further, as oxidative stress is associated with depression, we determined whether decreasing or increasing oxidative stress by administering methylsulfonylmethane (MSM) or diethylmaleate (DEM), respectively, altered depression-like behavior. GT-tg bigenic mice received intraperitoneal saline or doxycycline (Dox, 25-100 mg/kg/day) to induce Tat expression. G-tg mice, which do not express Tat protein, also received Dox. Depression-like behavior was assessed with the tail suspension test (TST) and the two-bottle saccharin/water consumption task. Reactive oxygen/nitrogen species (ROS/RNS) were assessed ex vivo. Medial frontal cortex (MFC) oxidative stress and temperature were measured in vivo with 9.4-Tesla proton magnetic resonance spectroscopy (MRS). Tat expression increased TST immobility time in an exposure-dependent manner and reduced saccharin consumption. MSM decreased immobility time while DEM increased it in saline-treated GT-tg mice. Tat and MSM behavioral effects persisted for 28 days. Tat and DEM increased while MSM decreased ROS/RNS levels. Tat expression increased MFC glutathione levels and temperature. Tat expression induced rapid and enduring depression-like behaviors and oxidative stress. Increasing/decreasing oxidative stress increased/decreased, respectively, depression-like behavior. Thus, Tat produced by HIV may contribute to the high depression prevalence among those with HIV. Further, mitigation of oxidative stress could reduce depression severity.

  7. Host-range restriction of vaccinia virus E3L deletion mutant can be overcome in vitro, but not in vivo, by expression of the influenza virus NS1 protein.

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    Susana Guerra

    Full Text Available During the last decades, research focused on vaccinia virus (VACV pathogenesis has been intensified prompted by its potential beneficial application as a vector for vaccine development and anti-cancer therapies, but also due to the fear of its potential use as a bio-terrorism threat. Recombinant viruses lacking a type I interferon (IFN antagonist are attenuated and hence good vaccine candidates. However, vaccine virus growth requires production in IFN-deficient systems, and thus viral IFN antagonists that are active in vitro, yet not in vivo, are of great value. The VACV E3 and influenza virus NS1 proteins are distinct double-stranded RNA-binding proteins that play an important role in pathogenesis by inhibiting the mammalian IFN-regulated innate antiviral response. Based on the functional similarities between E3 and NS1, we investigated the ability of NS1 to replace the biological functions of E3 of VACV in both in vitro and in vivo systems. For this, we generated a VACV recombinant virus lacking the E3L gene, yet expressing NS1 (VVΔE3L/NS1. Our study revealed that NS1 can functionally replace E3 in cultured cells, rescuing the protein synthesis blockade, and preventing apoptosis and RNA breakdown. In contrast, in vivo the VVΔE3L/NS1 virus was highly attenuated after intranasal inoculation, as it was unable to spread to the lungs and other organs. These results indicate that there are commonalities but also functional differences in the roles of NS1 and E3 as inhibitors of the innate antiviral response, which could potentially be utilized for vaccine production purposes in the future.

  8. Design and evaluation of protein expression in a recombinant plasmid encoding epitope gp 350/220 of the Epstein-Barr virus (EBV)

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    Himmah, Karimatul; Dluha, Nurul; Anyndita, Nadya V. M.; Rifa'i, Muhaimin; Widodo

    2017-05-01

    The Epstein - Barr virus (EBV) causes severe infections that may lead to cancers such as nasopharyngeal carcinoma. Development of effective EBV vaccines is necessary to prevent the virus spreading throughout the community. TheEBV has a surface protein gp 350/220, which serves as an antigen to help interact with host cells. Epitopes of the protein can potentially serve as bases for a vaccine. In a previous study, we have found a conserved epitope of gp 350/220 from all strains EBV through an in silico approach. The aim of this study is to design and overproduce a recombinant peptide of epitope gp 350/220 in E. coli. DNA encoding the conserved epitope was synthesized and cloned into plasmid pET-22b(+); the recombinant plasmid was transformed into E. coli strains DH5α and BL21. The transformed plasmid DNA was isolated and confirmed by restriction using XbaI and PstI enzymes followed by DNA sequencing. Protein expression was induced by isopropyl-D-thiogalactopyranoside (IPTG) with final concentrations of 0.1, 0.2, 1, and 2 mM in consecutive times. An osmotic shock method was used to isolate protein from periplasmic fraction of E. coli DH5α and BL21. The SDS-PAGE analysis was carried out to detect peptide target (3.4 kDa). Based on this result, the induction process did not work properly, and thus needs further investigation.

  9. Single-dose, therapeutic vaccination of mice with vesicular stomatitis virus expressing human papillomavirus type 16 E7 protein.

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    Liao, John B; Publicover, Jean; Rose, John K; DiMaio, Daniel

    2008-05-01

    We are developing recombinant attenuated vesicular stomatitis virus (VSV) as a vaccine vector to generate humoral and cell-mediated immune responses. Here, we explore the use of VSV vaccines for cancer immunotherapy. Immunotherapy targeting high-risk human papillomavirus (HPV) lesions has the potential to benefit HPV-infected individuals and cervical cancer patients by generating cytotoxic T cells that kill tumor cells that express viral antigens. A single dose of VSV expressing the HPV type 16 (HPV16) E7 oncogene was used for therapeutic vaccination of mice bearing TC-1 syngeneic tumors, which express HPV16 E7. HPV16 E7-specific T cells were generated and displayed cytotoxic activity against the tumor cells. By 14 days postvaccination, average tumor volumes were 10-fold less in the vaccinated group than in mice that received the empty-vector VSV, and regression of preexisting tumors occurred in some cases. This antitumor effect was CD8 T-cell dependent. Our results demonstrate antitumor responses to HPV16 E7 and suggest that recombinant-VSV-based vaccination should be explored as a therapeutic strategy for cervical carcinoma and other HPV-associated cancers.

  10. Expression of Foot-and-Mouth Disease Virus Non-Structural Protein, 3D in Insect Cells and its Application in Detection of Anti-FMDV Antibodies.

    Science.gov (United States)

    Kumar, Rakesh; Hosamani, M; Sreenivasa, B P; Kotyal, Anil; Venkataramanan, R

    2012-12-01

    Non-structural proteins (NSPs) based diagnostics are useful for large-scale sero-surveillance of foot-and-mouth disease (FMD) and to monitor viral activity as a follow up to the vaccination campaign in FMD endemic countries like India which aim at disease control through vaccination. These diagnostics are also handy in the serology of import/export of cloven-footed animals. In the present study, non-structural protein RNA polymerase (3D gene) of FMD virus (FMDV) was expressed using baculovirus expression system. Protein expression was analyzed by SDS-PAGE and confirmed by its immuno-reactivity with serum from a FMDV infected bovine, in the western blot. Recombinant 3D protein was purified and evaluated in the indirect ELISA with 1072 cattle serum samples. Diagnostic sensitivity and specificity of the assay were found to be 92 and 100 %, respectively, when tested with cattle sera of known FMD status. The 3D based ELISA developed here is useful for screening the animals as an adjunct to other NSP based diagnostics available for routine serosurveillance of FMD.

  11. Protective and immunogenic effects of Escherichia coli-expressed infectious pancreatic necrosis virus (IPNV) VP2-VP3 fusion protein in rainbow trout.

    Science.gov (United States)

    Dadar, Maryam; Memari, Hamid Rajabi; Vakharia, Vikram N; Peyghan, Rahim; Shapouri, MasodReza Seifi Abad; Mohammadian, Takavar; Hasanzadeh, Reza; Ghasemi, Mohades

    2015-11-01

    Infectious Pancreatic Necrosis Virus (IPNV) is a member of the family Birnaviridae which causes significant losses in the aquaculture industry. To develop a recombinant vaccine for IPNV, a cDNA construct of IPNV VP2-VP3 fusion gene was prepared and cloned into an Escherichia coli (E. coli) expression vector (pET-26b) to obtain recombinant protein products. A study was conducted to determine the antibody responses and protective capacity of this recombinant vaccine expressing VP2-VP3 fusion protein. Subsequently, juvenile rainbow trout were inoculated by injecting purified recombinant IPNV VP2-VP3 proteins, followed by challenge with virulent IPNV in rainbow trout. Our results demonstrate that recombinant E. coli derived VP2-VP3 fusion protein induced a strong and significantly (P rainbow trout challenged with virulent IPNV. This result was confirmed by measuring the viral loads of IPNV in immunized rainbow trout which was drastically reduced, as analyzed by real-time RT-PCR. In summary, we demonstrate that E. coli-expressed IPNV VP2-VP3 injectable vaccine is highly immunogenic and protective against IPNV infection. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Vero/BC-F: an efficient packaging cell line stably expressing F protein to generate single round-infectious human parainfluenza virus type 2 vector.

    Science.gov (United States)

    Ohtsuka, J; Fukumura, M; Tsurudome, M; Hara, K; Nishio, M; Kawano, M; Nosaka, T

    2014-08-01

    A stable packaging cell line (Vero/BC-F) constitutively expressing fusion (F) protein of the human parainfluenza virus type 2 (hPIV2) was established for production of the F-defective and single round-infectious hPIV2 vector in a strategy for recombinant vaccine development. The F gene expression has not evoked cytostatic or cytotoxic effects on the Vero/BC-F cells and the F protein was physiologically active to induce syncytial formation with giant polykaryocytes when transfected with a plasmid expressing hPIV2 hemagglutinin-neuraminidase (HN). Transduction of the F-defective replicon RNA into the Vero/BC-F cells led to the release of the infectious particles that packaged the replicon RNA (named as hPIV2ΔF) without detectable mutations, limiting the infectivity to a single round. The maximal titer of the hPIV2ΔF was 6.0 × 10(8) median tissue culture infections dose per ml. The influenza A virus M2 gene was inserted into hPIV2ΔF, and the M2 protein was found to be highly expressed in a human lung cancer cell line after transduction. Furthermore, in vivo airway infection experiments revealed that the hPIV2ΔF was capable of delivering transgenes to hamster tracheal cells. Thus, non-transmissible or single round-infectious hPIV2 vector will be potentially applicable to human gene therapy or recombinant vaccine development.

  13. [Recombinant expression of hantaan virus protein N with application of Western-blot in detecting anti-hantavirus antibody].

    Science.gov (United States)

    Yao, P P; Xu, F; Sun, Y S; Yang, Z R; Zhang, Y; Yue, M; Zhu, H P

    2017-04-10

    Objective: S gene of hantavirus(HV) was expressed in insect cells by genetic engineering technology. The expression product of S gene was used as antigen to detect anti-HV specific antibody IgG in serum. Methods: Gene encoding NP of the strain HV-Z10 was amplified by PCR and then its eukaryotic expression system rBAC-Z10S-TN was constructed by using the routine genetic engineering method. SDS-PAGE was applied to measure the expression of rNP.Ion-exchange plus Ni-NTA-affinity chromatography was performed to purify the recombinant product. Indirect immuno-fluorescence assay (IFA) was used to determine the specific immune-reactivity of rNP. WB assay was established to detect the serum samples from 95 confirmed HFRS patients. Parameters related to the outcomes of detection were compared with the routine HV-IgG IFA method. Results: rBAC-Z10S-TN was able to express rNP with high efficiency. The purified rNP only showed a single protein fragment in the gel after SDS-PAGE. HV IgG could efficiently recognize rNP and hybridize with the recombinant protein. 97.67% of the serum samples from the HFRS patients were positive confirmed by WB. Conclusions: We successfully constructed a high efficient prokaryotic expression system of NP encoding gene from hantavirus strain HV-Z10. WB assay which was established in this study could be used as a new serological test for HFRS diagnosis, thanks to the simplicity, safety, sensitivity and specificity of this method.

  14. Combined prime-boost vaccination against tick-borne encephalitis (TBE using a recombinant vaccinia virus and a bacterial plasmid both expressing TBE virus non-structural NS1 protein

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    Zakharova LG

    2005-08-01

    Full Text Available Abstract Background Heterologous prime-boost immunization protocols using different gene expression systems have proven to be successful tools in protecting against various diseases in experimental animal models. The main reason for using this approach is to exploit the ability of expression cassettes to prime or boost the immune system in different ways during vaccination procedures. The purpose of the project was to study the ability of recombinant vaccinia virus (VV and bacterial plasmid, both carrying the NS1 gene from tick-borne encephalitis (TBE virus under the control of different promoters, to protect mice against lethal challenge using a heterologous prime-boost vaccination protocol. Results The heterologous prime-boost vaccination protocol, using a VV recombinant and bacterial plasmid, both containing the NS1 TBE virus protein gene under the control of different promoters, achieved a high level of protection in mice against lethal challenge with a highly pathogenic TBE virus strain. No signs of pronounced TBE infection were detected in the surviving animals. Conclusion Heterologous prime-boost vaccination protocols using recombinant VV and bacterial plasmids could be used for the development of flavivirus vaccines.

  15. Cloning of fusion protein gene of Newcastle disease virus into a baculovirus derived bacmid shuttle vector, in order to express it in insect cell line

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    Hashemzadeh MS

    2015-05-01

    Full Text Available Abstract Background: Newcastle disease virus (NDV is one of the major pathogens in poultry and vaccination is intended to control the disease, as an effective solution, yet. Fusion protein (F on surface of NDV, has a fundamental role in virus pathogenicity and can induce protective immunity, alone. With this background, here our aim was to construct a baculovirus derived recombinant bacmid shuttle vector (encoding F-protein in order to express it in insect cell line. Materials and Methods: In this experimental study, at first complete F gene from avirulent strain La Sota of NDV was amplified by RT-PCR to produce F cDNA. The amplicon was cloned into T/A cloning vector and afterwards into pFastBac Dual donor plasmid. After the verification of cloning process by two methods, PCR and enzymatic digestion analysis, the accuracy of F gene sequence was confirmed by sequencing. Finally, F-containing recombinant bacmid was subsequently generated in DH10Bac cell and the construct production was confirmed by a special PCR panel, using F specific primers and M13 universal primers. Results: Analysis of confirmatory tests showed that the recombinant bacmid, expressing of F-protein gene in correct sequence and framework, has been constructed successfully. Conclusion: The product of this F-containing recombinant bacmid, in addition to its independent application in the induction of protective immunity, can be used with the other individual recombinant baculoviruses, expressing HN and NP genes to produce NDV-VLPs in insect cell line.

  16. Prognostic significance of catalase expression and its regulatory effects on hepatitis B virus X protein (HBx) in HBV-related advanced hepatocellular carcinomas

    Science.gov (United States)

    Cho, Mi-Young; Cheong, Jae Youn; Lim, Wonchung; Jo, Sujin; Lee, Youngsoo; Wang, Hee-Jung; Han, Kyou-Hoon; Cho, Hyeseong

    2014-01-01

    Hepatitis B virus X protein (HBx) plays a role in liver cancer development. We previously showed that ROS increased HBx levels and here, we investigated the role of antioxidants in the regulation of HBx expression and their clinical relevance. We found that overexpression of catalase induced a significant loss in HBx levels. The cysteine null mutant of HBx (Cys−) showed a dramatic reduction in its protein stability. In clonogenic proliferation assays, Huh7-X cells produced a significant number of colonies whereas Huh7-Cys− cells failed to generate them. The Cys at position 69 of HBx was crucial to maintain its protein stability and transactivation function in response to ROS. Among 50 HBV-related hepatocellular carcinoma (HCC) specimens, 72% of HCCs showed lower catalase levels than those of surrounding non-tumor tissues. In advanced stage IV, catalase levels in non-tumor tissues were increased whereas those in tumors were further reduced. Accordingly, patients with a high T/N ratio for catalase showed significantly longer survival than those with a low T/N ratio. Together, catalase expression in HCC patients can be clinically useful for prediction of patient survival, and restoration of catalase expression in HCCs could be an important strategy for intervention in HBV-induced liver diseases. PMID:25361011

  17. Comparative proteomics reveals that YK51, a 4-Hydroxypandurantin-A analogue, downregulates the expression of proteins associated with dengue virus infection

    Directory of Open Access Journals (Sweden)

    Wei-Lian Tan

    2018-01-01

    Full Text Available Dengue is endemic throughout tropical and subtropical regions of the world. Currently, there is no clinically approved therapeutic drug available for this acute viral infection. Although the first dengue vaccine Dengvaxia has been approved for use in certain countries, it is limited to those without a previous dengue infection while the safety and efficacy of the vaccine in those elderly and younger children still need to be identified. Therefore, it is becoming increasingly important to develop therapeutics/drugs to combat dengue virus (DENV infection. YK51 is a synthetic analogue of 4-Hydroxypandurantin A (a compound found in the crude extract of the rhizomes of Boesenbergia rotunda that has been extensively studied by our research group. It has been shown to possess outstanding antiviral activity due to its inhibitory activity against NS2B/NS3 DENV2 protease. However, it is not known how YK51 affects the proteome of DENV infected cells. Therefore, we performed a comparative proteomics analysis to identify changes in protein expression in DENV infected HepG2 cells treated with YK51. Classical two-dimensional gel electrophoresis followed by protein identification using tandem mass spectrometry was employed in this study. Thirty proteins were found to be down-regulated with YK51 treatment. In silico analysis predicted that the down-regulation of eight of these proteins may inhibit viral infection. Our results suggested that apart from inhibiting the NS2B/NS3 DENV2 protease, YK51 may also be causing the down-regulation of a number of proteins that may be responsible in, and/or essential to virus infection. However, functional characterization of these proteins will be necessary before we can conclusively determine their roles in DENV infection.

  18. Display of disparate transcription phenotype by the phosphorylation negative P protein mutants of vesicular stomatitis virus, Indiana serotype, expressed in E. coli and eucaryotic cells.

    Science.gov (United States)

    Mathur, M; Das, T; Chen, J L; Chattopadhyay, D; Banerjee, A K

    1997-01-01

    The phosphoprotein (P) of vesicular stomatitis virus (VSV) is a subunit of the RNA polymerase (L) that transcribes the negative strand genome RNA into mRNAs both in vitro and in vivo. We have recently shown that the P protein of VSV, New Jersey serotype (PNJ), expressed in E. coli, is biologically inactive unless phosphorylated at specific serine residues by cellular casein kinase II (CKII). In the present work, we are studying the role of phosphorylation in the activation of the P protein of Indiana serotype (PIND), which is highly nonhomologous in amino acid sequence yet structurally similar to its New Jersey counterpart. Despite the fact that E. coli-expressed PIND required phosphorylation by CKII for activation, the phosphorylation negative P protein mutants generated by altering the phosphate acceptors S and T to alanine, surprisingly, showed transcription activity similar to wild-type in vitro. Alteration of S and T residues to phenylalanine, similarly, supported substantial transcription activity (approx. 60% of wild-type), whereas substitution with arginine residue abrogated transcription (approx. 5% of wild-type). In contrast, the same mutants, when expressed in eucaryotic cells, exhibited greatly reduced transcription activity in vitro. This disparate display of transcription phenotype by the PIND mutants expressed in bacteria and eucaryotic cells suggests that these mutants are unique in assuming different secondary structure or conformation when synthesized in two different cellular milieu. The findings that, unless phosphorylated by CKII, the bacterially expressed unphosphorylated (P0) form of PIND, as well as the phosphorylation negative mutants expressed in eucaryotic cells, demonstrates transcription negative phenotype indicate that, like PNJ, phosphorylation of PIND is essential for its activity.

  19. Triptolide inhibits proliferation of Epstein–Barr virus-positive B lymphocytes by down-regulating expression of a viral protein LMP1

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Heng [Department of Pathogen Biology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Guo, Wei [Department of Pathology and Physiology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Long, Cong; Wang, Huan; Wang, Jingchao [Department of Pathogen Biology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Sun, Xiaoping, E-mail: xsun6@whu.edu.cn [Department of Pathogen Biology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); State Key Laboratory of Virology, Wuhan University, Wuhan 430072 (China)

    2015-01-16

    Highlights: • Triptolide inhibits proliferation of EBV-positive lymphoma cells in vitro and in vivo. • Triptolide reduces expression of LMP1 by decreasing its transcription level. • Triptolide inhibits ED-L1 promoter activity. - Abstract: Epstein–Barr virus (EBV) infects various types of cells and mainly establishes latent infection in B lymphocytes. The viral latent membrane protein 1 (LMP1) plays important roles in transformation and proliferation of B lymphocytes infected with EBV. Triptolide is a compound of Tripterygium extracts, showing anti-inflammatory, immunosuppressive, and anti-cancer activities. In this study, it is determined whether triptolide inhibits proliferation of Epstein–Barr virus-positive B lymphocytes. The CCK-8 assays were performed to examine cell viabilities of EBV-positive B95-8 and P3HR-1 cells treated by triptolide. The mRNA and protein levels of LMP1 were examined by real time-PCR and Western blotting, respectively. The activities of two LMP1 promoters (ED-L1 and TR-L1) were determined by Dual luciferase reportor assay. The results showed that triptolide inhibited the cell viability of EBV-positive B lymphocytes, and the over-expression of LMP1 attenuated this inhibitory effect. Triptolide decreased the LMP1 expression and transcriptional levels in EBV-positive B cells. The activity of LMP1 promoter ED-L1 in type III latent infection was strongly suppressed by triptolide treatment. In addition, triptolide strongly reduced growth of B95-8 induced B lymphoma in BALB/c nude mice. These results suggest that triptolide decreases proliferation of EBV-induced B lymphocytes possibly by a mechanism related to down-regulation of the LMP1 expression.

  20. Expression of foot-and-mouth disease virus capsid proteins in silkworm-baculovirus expression system and its utilization as a subunit vaccine.

    Directory of Open Access Journals (Sweden)

    Zhiyong Li

    Full Text Available BACKGROUND: Foot-and-mouth disease (FMD is a highly contagious disease of livestock that causes severe economic loss in susceptible cloven-hoofed animals. Although the traditional inactivated vaccine has been proved effective, it may lead to a new outbreak of FMD because of either incomplete inactivation of FMDV or the escape of live virus from vaccine production workshop. Thus, it is urgent to develop a novel FMDV vaccine that is safer, more effective and more economical than traditional vaccines. METHODOLOGY AND PRINCIPAL FINDINGS: A recombinant silkworm baculovirus Bm-P12A3C which contained the intact P1-2A and 3C protease coding regions of FMDV Asia 1/HNK/CHA/05 was developed. Indirect immunofluorescence test and sandwich-ELISA were used to verify that Bm-P12A3C could express the target cassette. Expression products from silkworm were diluted to 30 folds and used as antigen to immunize cattle. Specific antibody was induced in all vaccinated animals. After challenge with virulent homologous virus, four of the five animals were completely protected, and clinical symptoms were alleviated and delayed in the remaining one. Furthermore, a PD(50 (50% bovine protective dose test was performed to assess the bovine potency of the subunit vaccine. The result showed the subunit vaccine could achieve 6.34 PD(50 per dose. CONCLUSION: The results suggest that this strategy might be used to develop the new subunit FMDV vaccine.

  1. Interferon-α inhibits cell migration and invasion and induces the expression of antiviral proteins in Huh-7 cells transfected with hepatitis B virus X gene-expressing lentivirus.

    Science.gov (United States)

    Yang, Qian; Li, Xiao-Peng; Zhong, Yuan-Bin; Xiang, Tian-Xin; Zhang, Lun-Li

    2017-12-01

    Hepatitis B virus (HBV) X protein (HBx) serves an important role in HBV infection and the development of HBV-related liver cancer. Interferon-α (IFN-α) is used to treat patients with HBV; however, the role of IFN-α in the development of HBV-related liver cancer remains unclear. The present study established a new HBV-related liver cancer model (Huh-7-HBx) by transfecting the hepatoma cell line Huh-7, with HBx-expressing lentivirus. Following IFN-α treatment, cell viability, migration and invasion, as well as the expression of antiviral proteins in Huh-7-HBx, were subsequently determined. The results demonstrated that HBx-expressing lentivirus had no significant effect on cell viability but promoted the migration and invasion of Huh-7 cells. The expression of the antiviral genes IFN α and β receptor subunit 1 (IFNAR1), IFNAR2, IFN-stimulated gene factor 3, double-stranded RNA-activated protein kinase and ribonuclease L, was also increased. Following treatment of Huh-7-HBx cells with IFN-α, the expression of antiviral genes was increased at the level of transcription and translation, whereas cell migration and invasion was decreased. The present study suggests that IFN-α may attenuate the development of HBV-related liver cancer by reducing cell migration and invasion and promoting the expression of antiviral proteins.

  2. Molecular principles of human virus protein-protein interactions.

    Science.gov (United States)

    Halehalli, Rachita Ramachandra; Nagarajaram, Hampapathalu Adimurthy

    2015-04-01

    Viruses, from the human protein-protein interaction network perspective, target hubs, bottlenecks and interconnected nodes enriched in certain biological pathways. However, not much is known about the general characteristic features of the human proteins interacting with viral proteins (referred to as hVIPs) as well as the motifs and domains utilized by human-virus protein-protein interactions (referred to as Hu-Vir PPIs). Our study has revealed that hVIPs are mostly disordered proteins, whereas viral proteins are mostly ordered proteins. Protein disorder in viral proteins and hVIPs varies from one subcellular location to another. In any given viral-human PPI pair, at least one of the two proteins is structurally disordered suggesting that disorder associated conformational flexibility as one of the characteristic features of virus-host interaction. Further analyses reveal that hVIPs are (i) slowly evolving proteins, (ii) associated with high centrality scores in human-PPI network, (iii) involved in multiple pathways, (iv) enriched in eukaryotic linear motifs (ELMs) associated with protein modification, degradation and regulatory processes, (v) associated with high number of splice variants and (vi) expressed abundantly across multiple tissues. These aforementioned findings suggest that conformational flexibility, spatial diversity, abundance and slow evolution are the characteristic features of the human proteins targeted by viral proteins. Hu-Vir PPIs are mostly mediated via domain-motif interactions (DMIs) where viral proteins employ motifs that mimic host ELMs to bind to domains in human proteins. DMIs are shared among viruses belonging to different families indicating a possible convergent evolution of these motifs to help viruses to adopt common strategies to subvert host cellular pathways. Hu-Vir PPI data, DDI and DMI data for human-virus PPI can be downloaded from http://cdfd.org.in/labpages/computational_biology_datasets.html. Supplementary data are

  3. Visualization of X4- and R5-Tropic HIV-1 Viruses Expressing Fluorescent Proteins in Human Endometrial Cells: Application to Tropism Study.

    Science.gov (United States)

    Terrasse, Rachel; Memmi, Meriam; Palle, Sabine; Heyndrickx, Leo; Vanham, Guido; Pozzetto, Bruno; Bourlet, Thomas

    2017-01-01

    Worldwide most HIV infections occur through heterosexual transmission, involving complex interactions of cell-free and cell-associated particles with cells of the female genital tract mucosa. The ability of HIV-1 to "infect" epithelial cells remains poorly understood. To address this question, replicative-competent chimeric constructs expressing fluorescent proteins and harboring the envelope of X4- or R5-tropic HIV-1 strains were used to "infect" endometrial HEC1-A cells. The virus-cell interactions were visualized using confocal microscopy (CM) at various times post infection. Combined with quantification of viral RNA and total HIV DNA in infected cells, the CM pictures suggest that epithelial cells do not support a complete viral replication cycle: X4-tropic viruses are imported into the nucleus in a non-productive way, whereas R5-tropic viruses transit through the cytoplasm without replication and are preferentially transmitted to susceptible activated peripheral blood mononuclear cells. Within the limit of experiments conducted in vitro on a continued cell line, these results indicate that the epithelial mucosa may participate to the selection of HIV-1 strains at the mucosal level.

  4. Production of recombinant non-structural protein-3 hydrophobic domain deletion (NS3ΔHD) protein of bluetongue virus from prokaryotic expression system as an efficient diagnostic reagent.

    Science.gov (United States)

    Mohanty, Nihar Nalini; Chacko, Nirmal; Biswas, Sanchay Kumar; Chand, Karam; Pandey, Awadh Bihari; Mondal, Bimalendu; Hemadri, Divakar; Shivachandra, Sathish Bhadravati

    2016-09-01

    Serological diagnostics for bluetongue (BT), which is an infectious, non-contagious and arthropod-borne virus disease of ruminants, are primarily dependent on availability of high quality native or recombinant antigen(s) based on either structural/non-structural proteins in sufficient quantity. Non-structural proteins (NS1-NS4) of BT virus are presumed candidate antigens in development of DIVA diagnostics. In the present study, NS3 fusion gene encoding for NS3 protein containing the N- and C-termini with a deletion of two hydrophobic domains (118A to S141 aa and 162S to A182 aa) and intervening variable central domain (142D to K161 aa) of bluetongue virus 23 was constructed, cloned and over-expressed using prokaryotic expression system. The recombinant NS3ΔHD fusion protein (∼38 kDa) including hexa-histidine tag on its both termini was found to be non-cytotoxic to recombinant Escherichia coli cells and purified by affinity chromatography. The purified rNS3ΔHD fusion protein was found to efficiently detect BTV-NS3 specific antibodies in indirect-ELISA format with diagnostic sensitivity (DSn = 94.4%) and specificity (DSp = 93.9%). The study indicated the potential utility of rNS3ΔHD fusion protein as candidate diagnostic reagent in developing an indirect-ELISA for sero-surveillance of animals for BTV antibodies under DIVA strategy, wherever monovalent/polyvalent killed BT vaccine formulations devoid of NS proteins are being practiced for immunization. Copyright © 2016 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  5. Hepatitis C virus expressing flag-tagged envelope protein 2 has unaltered infectivity and density, is specifically neutralized by flag antibodies and can be purified by affinity chromatography

    DEFF Research Database (Denmark)

    Prentø, Jannick Cornelius; Bukh, Jens

    2011-01-01

    Hepatitis C virus (HCV) purification by ultracentrifugation is difficult because of the low and heterogeneous density of native and cultured viruses. It was recently shown that inserting flag tag into envelope protein 2 (E2) of HCV permitted virus purification by affinity chromatography. However...... to the original virus. Flag-tagged virus was susceptible to flag-specific antibody neutralization, and infected cells could be immuno-stained by anti-flag antibodies. Using affinity chromatography with anti-flag resin we repeatedly obtained ~30% recovery of infectious particles. The full viability and unaltered...

  6. Hepatitis C virus core protein targets 4E-BP1 expression and phosphorylation and potentiates Myc-induced liver carcinogenesis in transgenic mice.

    Science.gov (United States)

    Abdallah, Cosette; Lejamtel, Charlène; Benzoubir, Nassima; Battaglia, Serena; Sidahmed-Adrar, Nazha; Desterke, Christophe; Lemasson, Matthieu; Rosenberg, Arielle R; Samuel, Didier; Bréchot, Christian; Pflieger, Delphine; Le Naour, François; Bourgeade, Marie-Françoise

    2017-08-22

    Hepatitis C virus (HCV) is a leading cause of liver diseases including the development of hepatocellular carcinoma (HCC). Particularly, core protein has been involved in HCV-related liver pathologies. However, the impact of HCV core on signaling pathways supporting the genesis of HCC remains largely elusive. To decipher the host cell signaling pathways involved in the oncogenic potential of HCV core, a global quantitative phosphoproteomic approach was carried out. This study shed light on novel differentially phosphorylated proteins, in particular several components involved in translation. Among the eukaryotic initiation factors that govern the translational machinery, 4E-BP1 represents a master regulator of protein synthesis that is associated with the development and progression of cancers due to its ability to increase protein expression of oncogenic pathways. Enhanced levels of 4E-BP1 in non-modified and phosphorylated forms were validated in human hepatoma cells and in mouse primary hepatocytes expressing HCV core, in the livers of HCV core transgenic mice as well as in HCV-infected human primary hepatocytes. The contribution of HCV core in carcinogenesis and the status of 4E-BP1 expression and phosphorylation were studied in HCV core/Myc double transgenic mice. HCV core increased the levels of 4E-BP1 expression and phosphorylation and significantly accelerated the onset of Myc-induced tumorigenesis in these double transgenic mice. These results reveal a novel function of HCV core in liver carcinogenesis potentiation. They position 4E-BP1 as a tumor-specific target of HCV core and support the involvement of the 4E-BP1/eIF4E axis in hepatocarcinogenesis.

  7. Defining Optimized Properties of Modified mRNA to Enhance Virus- and DNA- Independent Protein Expression in Adult Stem Cells and Fibroblasts

    Directory of Open Access Journals (Sweden)

    Frauke Hausburg

    2015-02-01

    Full Text Available Background: By far, most strategies for cell reprogramming and gene therapy are based on the introduction of DNA after viral delivery. To avoid the high risks accompanying these goals, non-viral and DNA-free delivery methods for various cell types are required. Methods: Relying on an initially established PCR-based protocol for convenient template DNA production, we synthesized five differently modified EGFP mRNA (mmRNA species, incorporating various degrees of 5-methylcytidine-5'-triphosphate (5mC and pseudouridine-5'-triphosphate (Ψ. We then investigated their effect on i protein expression efficiencies and ii cell viability for human mesenchymal stem cells (hMSCs and fibroblasts from different origins. Results: Our protocol allows highly efficient mmRNA production in vitro, enabling rapid and stable protein expression after cell transfection. However, our results also demonstrate that the terminally optimal modification needs to be defined in pilot experiments for each particular cell type. Transferring our approach to the conversion of fibroblasts into skeletal myoblasts using mmRNA encoding MyoD, we confirm the huge potential of mmRNA based protein expression for virus- and DNA-free reprogramming strategies. Conclusion: The achieved high protein expression levels combined with good cell viability not only in fibroblasts but also in hMSCs provides a promising option for mmRNA based modification of various cell types including slowly proliferating adult stem cells. Therefore, we are confident that our findings will substantially contribute to the improvement of efficient cell reprogramming and gene therapy approaches.

  8. Cytotoxic effect of co-expression of human hepatitis A virus 3C protease and bifunctional suicide protein FCU1 genes in a bicistronic vector.

    Science.gov (United States)

    Komissarov, Alexey; Demidyuk, Ilya; Safina, Dina; Roschina, Marina; Shubin, Andrey; Lunina, Nataliya; Karaseva, Maria; Kostrov, Sergey

    2017-08-01

    Recent reports on various cancer models demonstrate a great potential of cytosine deaminase/5-fluorocytosine suicide system in cancer therapy. However, this approach has limited success and its application to patients has not reached the desirable clinical significance. Accordingly, the improvement of this suicide system is an actively developing trend in gene therapy. The purpose of this study was to explore the cytotoxic effect observed after co-expression of hepatitis A virus 3C protease (3C) and yeast cytosine deaminase/uracil phosphoribosyltransferase fusion protein (FCU1) in a bicistronic vector. A set of mono- and bicistronic plasmid constructs was generated to provide individual or combined expression of 3C and FCU1. The constructs were introduced into HEK293 and HeLa cells, and target protein synthesis as well as the effect of 5-fluorocytosine on cell death and the time course of the cytotoxic effect was studied. The obtained vectors provide for the synthesis of target proteins in human cells. The expression of the genes in a bicistronic construct provide for the cytotoxic effect comparable to that observed after the expression of genes in monocistronic constructs. At the same time, co-expression of FCU1 and 3C recapitulated their cytotoxic effects. The combined effect of the killer and suicide genes was studied for the first time on human cells in vitro. The integration of different gene therapy systems inducing cell death (FCU1 and 3C genes) in a bicistronic construct allowed us to demonstrate that it does not interfere with the cytotoxic effect of each of them. A combination of cytotoxic genes in multicistronic vectors can be used to develop pluripotent gene therapy agents.

  9. Targeting CTCF to Control Virus Gene Expression: A Common Theme amongst Diverse DNA Viruses.

    Science.gov (United States)

    Pentland, Ieisha; Parish, Joanna L

    2015-07-06

    All viruses target host cell factors for successful life cycle completion. Transcriptional control of DNA viruses by host cell factors is important in the temporal and spatial regulation of virus gene expression. Many of these factors are recruited to enhance virus gene expression and thereby increase virus production, but host cell factors can also restrict virus gene expression and productivity of infection. CCCTC binding factor (CTCF) is a host cell DNA binding protein important for the regulation of genomic chromatin boundaries, transcriptional control and enhancer element usage. CTCF also functions in RNA polymerase II regulation and in doing so can influence co-transcriptional splicing events. Several DNA viruses, including Kaposi's sarcoma-associated herpesvirus (KSHV), Epstein-Barr virus (EBV) and human papillomavirus (HPV) utilize CTCF to control virus gene expression and many studies have highlighted a role for CTCF in the persistence of these diverse oncogenic viruses. CTCF can both enhance and repress virus gene expression and in some cases CTCF increases the complexity of alternatively spliced transcripts. This review article will discuss the function of CTCF in the life cycle of DNA viruses in the context of known host cell CTCF functions.

  10. Recombinant canine distemper virus strain snyder hill expressing green or red fluorescent proteins causes meningoencephalitis in the ferret

    NARCIS (Netherlands)

    M. Ludlow (Martin); D.T. Nguyen (Tien); D. Silin; O. Lyubomska; R.D. de Vries (Rory); V. von Messling; S. McQuaid (Stephen); R.L. de Swart (Rik); W.P. Duprex (Paul)

    2012-01-01

    textabstractThe propensity of canine distemper virus (CDV) to spread to the central nervous system is one of the primary features of distemper. Therefore, we developed a reverse genetics system based on the neurovirulent Snyder Hill (SH) strain of CDV (CDVSH) and show that this virus rapidly

  11. Effect of latent membrane protein 1 expression on overall survival in Epstein-Barr virus-associated cancers: a literature-based meta-analysis.

    Science.gov (United States)

    Chen, Yu-Pei; Zhang, Wen-Na; Chen, Lei; Tang, Ling-Long; Mao, Yan-Ping; Li, Wen-Fei; Liu, Xu; Zhou, Guan-Qun; Sun, Ying; Kang, Tie-Bang; Zeng, Mu-Sheng; Liu, Na; Ma, Jun

    2015-10-06

    Latent membrane protein 1 (LMP1) is identified as the main transforming oncoprotein of Epstein-Barr virus (EBV). LMP1 is frequently expressed in a variety of EBV-associated cancers, including nasopharyngeal carcinoma (NPC), non-Hodgkin lymphoma (NHL), Hodgkin disease (HD), and gastric cancer (GC). However, due to conflicting results, the prognostic value of LMP1 expression on clinical outcomes in EBV-associated cancers remains unclear. We performed a meta-analysis on 32 studies with a total of 3752 patients to explore the association between LMP1 expression and overall survival (OS) in EBV-associated cancers. Overall, LMP1 expression was significantly associated with poorer OS (hazard ratio, HR = 1.51, 95% confidence interval, CI, 1.13-2.03), irrespective of cancer type. Further analyses showed that LMP1 expression correlated with poorer OS in NPC (HR = 2.48, 95% CI, 1.77-3.47) and NHL patients (HR = 1.83, 95% CI, 1.07-3.15), but not in HD patients (HR = 0.98, 95% CI, 0.60-1.62) or GC patients (HR = 0.70, 95% CI, 0.44-1.12). Subgroup analyses indicated that the age and geographical factors seemed to have an effect on the clinical outcomes of HD patients with positive LMP1 expression. In conclusion, LMP1 expression can be used as a prognostic biomarker in NPC, NHL, and certain HD patients. This data suggests that novel therapies targeting LMP1 may improve clinical outcomes for EBV-associated cancer patients.

  12. Recombinant human adenovirus-5 expressing capsid proteins of Indian vaccine strains of foot-and-mouth disease virus elicits effective antibody response in cattle

    Science.gov (United States)

    Recombinant adenovirus-5 vectored foot-and-mouth disease constructs (Ad5- FMD) were made for three Indian vaccine virus serotypes O,A and Asia 1. Constructs co-expressing foot-and- mouth disease virus (FMDV) capsid and viral 3C protease sequences, were evaluated for their ability to induce a neutral...

  13. Abundant synthesis of functional human T-cell leukemia virus type I p40x protein in eucaryotic cells by using a baculovirus expression vector.

    Science.gov (United States)

    Jeang, K T; Giam, C Z; Nerenberg, M; Khoury, G

    1987-01-01

    The human T-cell leukemia virus type I (HTLV-I) p40x protein is a 40-kilodalton polypeptide encoded in the 3'-terminal region of the virus. This protein is responsible for positive transcriptional trans-activation of promoter elements located within the HTLV-I long terminal repeat. We introduced the protein-coding region of HTLV-I p40x into the genome of the baculovirus Autographa californica nuclear polyhedrosis virus. After infection of the insect Spodoptera frugiperda (SF9) cell line, this recombinant strain of baculovirus produced approximately 200 mg of intact p40x protein per 2.5 X 10(8) cells. The protein was biologically active in trans-activation of an HTLV-I long terminal repeat-human beta-globin construct. Biochemical analyses of the protein suggest that the p40x polypeptide underwent posttranslational modification in these eucaryotic SF9 cells. Images PMID:3027397

  14. Free fatty acids or high-concentration glucose enhances hepatitis A virus replication in association with a reduction in glucose-regulated protein 78 expression.

    Science.gov (United States)

    Nwe Win, Nan; Kanda, Tatsuo; Nakamura, Masato; Nakamoto, Shingo; Okamoto, Hiroaki; Yokosuka, Osamu; Shirasawa, Hiroshi

    2017-01-29

    Although the interaction between host and hepatitis A virus (HAV) factors could lead to severe hepatitis A, the exact mechanism of acute liver failure caused by HAV infection is not yet fully understood. The effects of metabolic diseases such as dyslipidemia or diabetes mellitus on HAV replication are still unknown. Here, we examined the effects of free fatty acids or high-concentration glucose on HAV replication and the effects on mitogen-activated protein kinase signaling pathway-related genes in human hepatocytes. We discovered a novel effect of free fatty acids or high-concentration glucose on HAV replication in association with a reduction in the expression of glucose-regulated protein 78 (GRP78). We also observed that thapsigargin induced GRP78 expression and inhibited HAV replication. These findings may provide a new interpretation of the relationship between metabolic diseases and severity of hepatitis A and suggest a new understanding of the mechanism of severe HAV infection. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Replication-competent fluorescent-expressing influenza B virus.

    Science.gov (United States)

    Nogales, Aitor; Rodríguez-Sánchez, Irene; Monte, Kristen; Lenschow, Deborah J; Perez, Daniel R; Martínez-Sobrido, Luis

    2016-02-02

    Influenza B viruses (IBVs) cause annual outbreaks of respiratory illness in humans and are increasingly recognized as a major cause of influenza-associated morbidity and mortality. Studying influenza viruses requires the use of secondary methodologies to identify virus-infected cells. To this end, replication-competent influenza A viruses (IAVs) expressing easily traceable fluorescent proteins have been recently developed. In contrast, similar approaches for IBV are mostly lacking. In this report, we describe the generation and characterization of replication-competent influenza B/Brisbane/60/2008 viruses expressing fluorescent mCherry or GFP fused to the C-terminal of the viral non-structural 1 (NS1) protein. Fluorescent-expressing IBVs display similar growth kinetics and plaque phenotype to wild-type IBV, while fluorescent protein expression allows for the easy identification of virus-infected cells. Without the need of secondary approaches to monitor viral infection, fluorescent-expressing IBVs represent an ideal approach to study the biology of IBV and an excellent platform for the rapid identification and characterization of antiviral therapeutics or neutralizing antibodies using high-throughput screening approaches. Lastly, fluorescent-expressing IBVs can be combined with the recently described reporter-expressing IAVs for the identification of novel therapeutics to combat these two important human respiratory pathogens. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Insertions in the gG Gene of Pseudorabies Virus Reduce Expression of the Upstream Us3 Protein and Inhibit Cell-to-Cell Spread of Virus Infection

    OpenAIRE

    Demmin, Gretchen L.; Clase, Amanda C.; Randall, Jessica A.; Enquist, L.W.; Banfield, Bruce W.

    2001-01-01

    The alphaherpesvirus Us4 gene encodes glycoprotein G (gG), which is conserved in most viruses of the alphaherpesvirus subfamily. In the swine pathogen pseudorabies virus (PRV), mutant viruses with internal deletions and insertions in the gG gene have shown no discernible phenotypes. We report that insertions in the gG locus of the attenuated PRV strain Bartha show reduced virulence in vivo and are defective in their ability to spread from cell to cell in a cell-type-specific manner. Similar i...

  17. Relationship of intratumoural protein expression patterns to age and Epstein-Barr virus status in classical Hodgkin lymphoma

    DEFF Research Database (Denmark)

    Ludvigsen, Maja; Kamper, Peter; Hamilton-Dutoit, Stephen Jacques

    2015-01-01

    In Western countries, the age distribution of Hodgkin lymphoma (HL) follows a characteristic bimodal curve showing an early and a late peak at approximately 35 and 70 yr, respectively. Furthermore, the presence of latent Epstein-Barr virus (EBV) genome in the Hodgkin Reed-Sternberg cells, the tum......In Western countries, the age distribution of Hodgkin lymphoma (HL) follows a characteristic bimodal curve showing an early and a late peak at approximately 35 and 70 yr, respectively. Furthermore, the presence of latent Epstein-Barr virus (EBV) genome in the Hodgkin Reed-Sternberg cells...

  18. Hepatitis B virus X protein promotes interleukin-7 receptor expression via NF-κB and Notch1 pathway to facilitate proliferation and migration of hepatitis B virus-related hepatoma cells

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    Fanyun Kong

    2016-11-01

    Full Text Available Abstract Background Interleukin-7 receptor (IL-7R is involved in the abnormal function of solid tumors, but the role and regulatory mechanisms of IL-7R in HBV-related hepatocellular carcinoma (HCC are still unclear. Methods Gene and protein expression levels of IL-7R were examined in hepatoma cells transfected with hepatitis B virus (HBV plasmids and in hepatoma cells transfected with the multifunctional nonstructural protein X (HBX. The expression of HBX and IL-7R was measured by immunohistochemical analysis in HBV-related HCC tissues. The role of NF-κB and Notch1 pathways in HBX-mediated expression of IL-7R in hepatoma cells was examined. Activation of IL-7R downstream of intracellular signaling proteins AKT, JNK, STAT5, and the associated molecules CyclinD1 and matrix metalloproteinase-9 (MMP-9, was assessed in HBX-positive cells with or without treatment with IL-7R short hairpin RNA (shRNA. Additionally, the role of IL-7R in HBX-mediated proliferation and migration of hepatoma cells was investigated. Results The expression of IL-7R was increased in hepatoma cells transfected with HBV plasmids; HBX was responsible for the HBV-mediated upregulation of IL-7R. Compared to adjacent tissues, the expression of HBX and IL-7R was increased in HBV-related HCC tissues. Additionally, the relative expression levels of HBX were associated with IL-7R in HBV-related HCC tissues. The activation of NF-κB pathways and expression of Notch1 were increased in hepatoma cells transfected with HBX, and inhibition of NF-κB and Notch1 pathways significantly decreased HBX-mediated expression of IL-7R. The activation of AKT and JNK and the expression of CyclinD1 and MMP-9 were increased in HBX-positive cells. When cells were treated with IL-7R shRNA, the activation of AKT and JNK, as well as the expression of CyclinD1 and MMP-9, were significantly inhibited. Additionally, IL-7R was responsible for HBX-induced proliferation and migration ability of hepatoma cells

  19. Packaging and Prefusion Stabilization Separately and Additively Increase the Quantity and Quality of Respiratory Syncytial Virus (RSV)-Neutralizing Antibodies Induced by an RSV Fusion Protein Expressed by a Parainfluenza Virus Vector.

    Science.gov (United States)

    Liang, Bo; Ngwuta, Joan O; Herbert, Richard; Swerczek, Joanna; Dorward, David W; Amaro-Carambot, Emerito; Mackow, Natalie; Kabatova, Barbora; Lingemann, Matthias; Surman, Sonja; Yang, Lijuan; Chen, Man; Moin, Syed M; Kumar, Azad; McLellan, Jason S; Kwong, Peter D; Graham, Barney S; Schaap-Nutt, Anne; Collins, Peter L; Munir, Shirin

    2016-11-01

    Human respiratory syncytial virus (RSV) and human parainfluenza virus type 3 (HPIV3) are major pediatric respiratory pathogens that lack vaccines. A chimeric bovine/human PIV3 (rB/HPIV3) virus expressing the unmodified, wild-type (wt) RSV fusion (F) protein from an added gene was previously evaluated in seronegative children as a bivalent intranasal RSV/HPIV3 vaccine, and it was well tolerated but insufficiently immunogenic for RSV F. We recently showed that rB/HPIV3 expressing a partially stabilized prefusion form (pre-F) of RSV F efficiently induced "high-quality" RSV-neutralizing antibodies, defined as antibodies that neutralize RSV in vitro without added complement (B. Liang et al., J Virol 89:9499-9510, 2015, doi:10.1128/JVI.01373-15). In the present study, we modified RSV F by replacing its cytoplasmic tail (CT) domain or its CT and transmembrane (TM) domains (TMCT) with counterparts from BPIV3 F, with or without pre-F stabilization. This resulted in RSV F being packaged in the rB/HPIV3 particle with an efficiency similar to that of RSV particles. Enhanced packaging was substantially attenuating in hamsters (10- to 100-fold) and rhesus monkeys (100- to 1,000-fold). Nonetheless, TMCT-directed packaging substantially increased the titers of high-quality RSV-neutralizing serum antibodies in hamsters. In rhesus monkeys, a strongly additive immunogenic effect of packaging and pre-F stabilization was observed, as demonstrated by 8- and 30-fold increases of RSV-neutralizing serum antibody titers in the presence and absence of added complement, respectively, compared to pre-F stabilization alone. Analysis of vaccine-induced F-specific antibodies by binding assays indicated that packaging conferred substantial stabilization of RSV F in the pre-F conformation. This provides an improved version of this well-tolerated RSV/HPIV3 vaccine candidate, with potently improved immunogenicity, which can be returned to clinical trials. Human respiratory syncytial virus (RSV) and

  20. Increased in vitro glial fibrillary acidic protein expression, telomerase activity, and telomere length after productive human immunodeficiency virus-1 infection in murine astrocytes.

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    Ojeda, Diego; López-Costa, Juan José; Sede, Mariano; López, Ester María; Berria, María Isabel; Quarleri, Jorge

    2014-02-01

    Although HIV-associated neurocognitive disorders (HAND) result from injury and loss of neurons, productive infection routinely takes place in cells of macrophage lineage. In such a complex context, astrocytosis induced by local chemokines/cytokines is one of the hallmarks of HIV neuropathology. Whether this sustained astrocyte activation is able to alter telomere-aging process is unknown. We hypothesized that interaction of HIV with astrocytes may impact astrocyte telomerase activity (TA) and telomere length in a scenario of astrocytic activation measured by expression of glial fibrillary acidic protein (GFAP). To test this hypothesis, cultured murine astrocytes were challenged with pseudotyped HIV/vesicular stomatitis virus (HIV/VSV) to circumvent the absence of viral receptors; and GFAP, telomerase activity, and telomere length were quantified. As an early and transient event after HIV infection, both TA activity and telomere length were significantly augmented (P < 0.001). Later, a strong negative correlation (-0.8616, P < 0.0001) between virus production and telomerase activity was demonstrated. Once HIV production had reached a peak (7 dpi), the TA decreased, showing levels similar to those of noninfected cells. In contrast, the astrocyte became activated, exhibiting significantly increased levels of GFAP expression directly related to the level of HIV/VSV replication (P < 0.0001). Our results suggest that HIV-infected astrocytes exhibit early disturbance in their cellular functions, such as telomerase activity and telomere length, that may attenuate cell proliferation and enhance the astrocyte dysregulation, contributing to HIV neuropathogenesis. Understanding the mechanisms involved in HIV-mediated persistence by altering the telomere-related aging processes could aid in the development of therapeutic modalities for neurological complications of HIV infection. Copyright © 2013 Wiley Periodicals, Inc.

  1. Nucleocytoplasmic Shuttling of Influenza A Virus Proteins

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    Jing Li

    2015-05-01

    Full Text Available Influenza viruses transcribe and replicate their genomes in the nuclei of infected host cells. The viral ribonucleoprotein (vRNP complex of influenza virus is the essential genetic unit of the virus. The viral proteins play important roles in multiple processes, including virus structural maintenance, mediating nucleocytoplasmic shuttling of the vRNP complex, virus particle assembly, and budding. Nucleocytoplasmic shuttling of viral proteins occurs throughout the entire virus life cycle. This review mainly focuses on matrix protein (M1, nucleoprotein (NP, nonstructural protein (NS1, and nuclear export protein (NEP, summarizing the mechanisms of their nucleocytoplasmic shuttling and the regulation of virus replication through their phosphorylation to further understand the regulation of nucleocytoplasmic shuttling in host adaptation of the viruses.

  2. Recombinant subgroup B human respiratory syncytial virus expressing enhanced green fluorescent protein efficiently replicates in primary human cells and is virulent in cotton rats.

    Science.gov (United States)

    Lemon, Ken; Nguyen, D Tien; Ludlow, Martin; Rennick, Linda J; Yüksel, Selma; van Amerongen, Geert; McQuaid, Stephen; Rima, Bert K; de Swart, Rik L; Duprex, W Paul

    2015-03-01

    Human respiratory syncytial virus (HRSV) is the most important viral cause of severe respiratory tract disease in infants. Two subgroups (A and B) have been identified, which cocirculate during, or alternate between, yearly epidemics and cause indistinguishable disease. Existing in vitro and in vivo models of HRSV focus almost exclusively on subgroup A viruses. Here, a recombinant (r) subgroup B virus (rHRSV(B05)) was generated based on a consensus genome sequence obtained directly from an unpassaged clinical specimen from a hospitalized infant. An additional transcription unit containing the gene encoding enhanced green fluorescent protein (EGFP) was introduced between the phosphoprotein and matrix genes (position 5) of the genome to generate rHRSV(B05)EGFP(5). The recombinant viruses replicated efficiently in both HEp-2 cells and in well-differentiated normal human bronchial cells grown at air-liquid interface. Intranasal infection of cotton rats (Sigmodon hispidus) resulted in high numbers of EGFP(+) cells in epithelia of the nasal septum and conchae. When administered in a relatively large inoculum volume, the virus also replicated efficiently in bronchiolar epithelial cells and spread extensively in both the upper and lower respiratory tracts. Virus replication was not observed in ciliated epithelial cells of the trachea. This is the first virulent rHRSV strain with the genetic composition of a currently circulating wild-type virus. In vivo tracking of infected cells by means of EGFP fluorescence in the absence of cytopathic changes increases the sensitivity of virus detection in HRSV pathogenesis studies. Virology as a discipline has depended on monitoring cytopathic effects following virus culture in vitro. However, wild-type viruses isolated from patients often do not cause significant changes to infected cells, necessitating blind passage. This can lead to genetic and phenotypic changes and the generation of high-titer, laboratory-adapted viruses with

  3. Vaccination with recombinant adenovirus expressing peste des petits ruminants virus-F or -H proteins elicits T cell responses to epitopes that arises during PPRV infection.

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    Rojas, José Manuel; Avia, Miguel; Pascual, Elena; Sevilla, Noemí; Martín, Verónica

    2017-11-21

    Peste des petits ruminants virus (PPRV) causes an economically important disease that limits productivity in small domestic ruminants and often affects the livestock of the poorest populations in developing countries. Animals that survive PPRV develop strong cellular and humoral responses, which are probably necessary for protection. Vaccination should thus aim at mimicking these natural responses. Immunization strategies against this morbillivirus using recombinant adenoviruses expressing PPRV-F or -H proteins can protect PPRV-challenged animals and permit differentiation of infected from vaccinated animals. Little is known of the T cell repertoire these recombinant vaccines induce. In the present work, we identified several CD4+ and CD8+ T cell epitopes in sheep infected with PPRV. We also show that recombinant adenovirus vaccination induced T cell responses to the same epitopes, and led to memory T cell differentiation. T cells primed by these recombinant adenovirus vaccines expanded after PPRV challenge and probably contributed to protection. These data validate the use of recombinant adenovirus expressing PPRV genes as DIVA strategies to control this highly contagious disease.

  4. Vaccination with recombinant modified vaccinia virus Ankara expressing bovine respiratory syncytial virus (bRSV) proteins protects calves against RSV challenge

    NARCIS (Netherlands)

    Antonis, A.F.G.; Most, van der R.G.; Suezer, Y.; Stockhofe-Zurwieden, N.; Daus, F.J.; Sutter, G.; Schrijver, R.S.

    2007-01-01

    Respiratory syncytial virus (RSV) is a major cause of severe respiratory disease in infants and calves. Bovine RSV (bRSV) is a natural pathogen for cattle, and bRSV infection in calves shares many features with the human infection. Thus, bRSV infection in cattle provides the ideal setting to

  5. [Hepatitis B virus X protein promotes insulin-like growth factor II gene expression by inducing hypomethylation of the P3 promoter in hepatocellular carcinoma].

    Science.gov (United States)

    Tang, Shaohui; Zhang, Shaohua; Zhang, Xiaojuan; Wu, Shenglan; Li, Junfeng; Jiang, Xiangwu; Zhou, Hongke; Luo, Yuhong; Cao, Mingrong

    2014-04-01

    To explore the involvement of hepatitis B X protein (HBx) in promoter 3 (P3)-driven mRNA overexpression of the insulin-like growth factor II gene (IGF-II) and investigate the underlying epigenetic mechanism. Levels of P3 and HBx mRNA and status of P3 methylation were analyzed in human hepatocellular carcinoma (HCC) samples, with and without hepatitis B virus (HBV) infection, using quantitative reverse transcription-PCR and bisulfite sequencing. In addition, the levels of P3 mRNA and P3 methylation were examined in HepG2 cells stably overexpressing HBx (HepG2-HBx). Finally, P3 promoter-luciferase constructs were cotransfected into HepG2 cells along with an HBx-expressing plasmid, and the effects of HBx on transcriptional activity and methylation of P3 were analyzed. Statistical analyses of the data were conducted by chi square test, Fisher's exact test, Student's t-test, Marn-Whitney U test, and Pearson's correlation coefficient test. The HBV-positive HCC specimens had significantly higher levels of P3 mRNA than the HBV-negative HCC specimens (-9.59 ± 3.22 vs. -12.97 ± 3.08 delta CT; P=0.006) but significantly lower levels of P3 methylation (mean values for the 17 CpG sites (36.9% ± 15.5% vs. 52.1% ± 19.1%; P=0.025). The P3 transcript abundance was positively correlated with the level of HBx expression and negatively correlated with the level of P3 methylation. The epigenetic results from experiments with the HepG2-HBx cells were similar. Transfection of HBx significantly decreased P3 methylation level and increased its activity. HBx expression may promote IGF-II expression by inducing hypomethylation of its P3 promoter in hepatocellular carcinoma.

  6. A Sequence-Independent, Unstructured Internal Ribosome Entry Site Is Responsible for Internal Expression of the Coat Protein of Turnip Crinkle Virus.

    Science.gov (United States)

    May, Jared; Johnson, Philip; Saleem, Huma; Simon, Anne E

    2017-04-15

    To maximize the coding potential of viral genomes, internal ribosome entry sites (IRES) can be used to bypass the traditional requirement of a 5' cap and some/all of the associated translation initiation factors. Although viral IRES typically contain higher-order RNA structure, an unstructured sequence of about 84 nucleotides (nt) immediately upstream of the Turnip crinkle virus (TCV) coat protein (CP) open reading frame (ORF) has been found to promote internal expression of the CP from the genomic RNA (gRNA) both in vitro and in vivo An absence of extensive RNA structure was predicted using RNA folding algorithms and confirmed by selective 2'-hydroxyl acylation analyzed by primer extension (SHAPE) RNA structure probing. Analysis of the IRES region in vitro by use of both the TCV gRNA and reporter constructs did not reveal any sequence-specific elements but rather suggested that an overall lack of structure was an important feature for IRES activity. The CP IRES is A-rich, independent of orientation, and strongly conserved among viruses in the same genus. The IRES was dependent on eIF4G, but not eIF4E, for activity. Low levels of CP accumulated in vivo in the absence of detectable TCV subgenomic RNAs, strongly suggesting that the IRES was active in the gRNA invivo Since the TCV CP also serves as the viral silencing suppressor, early translation of the CP from the viral gRNA is likely important for countering host defenses. Cellular mRNA IRES also lack extensive RNA structures or sequence conservation, suggesting that this viral IRES and cellular IRES may have similar strategies for internal translation initiation.IMPORTANCE Cap-independent translation is a common strategy among positive-sense, single-stranded RNA viruses for bypassing the host cell requirement of a 5' cap structure. Viral IRES, in general, contain extensive secondary structure that is critical for activity. In contrast, we demonstrate that a region of viral RNA devoid of extensive secondary

  7. A Single-Dose Recombinant Parainfluenza Virus 5-Vectored Vaccine Expressing Respiratory Syncytial Virus (RSV) F or G Protein Protected Cotton Rats and African Green Monkeys from RSV Challenge.

    Science.gov (United States)

    Wang, Dai; Phan, Shannon; DiStefano, Daniel J; Citron, Michael P; Callahan, Cheryl L; Indrawati, Lani; Dubey, Sheri A; Heidecker, Gwendolyn J; Govindarajan, Dhanasekaran; Liang, Xiaoping; He, Biao; Espeseth, Amy S

    2017-06-01

    Human respiratory syncytial virus (RSV) is a common cause of severe respiratory disease among infants, immunocompromised individuals, and the elderly. No licensed vaccine is currently available. In this study, we evaluated two parainfluenza virus 5 (PIV5)-vectored vaccines expressing RSV F (PIV5/F) or G (PIV5/G) protein in the cotton rat and African green monkey models for their replication, immunogenicity, and efficacy of protection against RSV challenge. Following a single intranasal inoculation, both animal species shed the vaccine viruses for a limited time but without noticeable clinical symptoms. In cotton rats, the vaccines elicited RSV F- or G-specific serum antibodies and conferred complete lung protection against RSV challenge at doses as low as 103 PFU. Neither vaccine produced the enhanced lung pathology observed in animals immunized with formalin-inactivated RSV. In African green monkeys, vaccine-induced serum and mucosal antibody responses were readily detected, as well. PIV5/F provided nearly complete protection against RSV infection in the upper and lower respiratory tract at a dose of 106 PFU of vaccine. At the same dose levels, PIV5/G was less efficacious. Both PIV5/F and PIV5/G were also able to boost neutralization titers in RSV-preexposed African green monkeys. Overall, our data indicated that PIV5/F is a promising RSV vaccine candidate.IMPORTANCE A safe and efficacious respiratory syncytial virus (RSV) vaccine remains elusive. We tested the recombinant parainfluenza virus 5 (PIV5) vectors expressing RSV glycoproteins for their immunogenicity and protective efficacy in cotton rats and African green monkeys, which are among the best available animal models to study RSV infection. In both species, a single dose of intranasal immunization with PIV5-vectored vaccines was able to produce systemic and local immunity and to protect animals from RSV challenge. The vaccines could also boost RSV neutralization antibody titers in African green monkeys

  8. Hepatitis B virus X protein induces EpCAM expression via active DNA demethylation directed by RelA in complex with EZH2 and TET2.

    Science.gov (United States)

    Fan, H; Zhang, H; Pascuzzi, P E; Andrisani, O

    2016-02-11

    Chronic hepatitis B virus (HBV) infection is a major risk factor for developing hepatocellular carcinoma (HCC), and HBV X protein (HBx) acts as cofactor in hepatocarcinogenesis. In liver tumors from animals modeling HBx- and HBV-mediated hepatocarcinogenesis, downregulation of chromatin regulating proteins SUZ12 and ZNF198 induces expression of several genes, including epithelial cell adhesion molecule (EpCAM). EpCAM upregulation occurs in HBV-mediated HCCs and hepatic cancer stem cells, by a mechanism not understood. Herein we demonstrate HBx induces EpCAM expression via active DNA demethylation. In hepatocytes, EpCAM is silenced by polycomb repressive complex 2 (PRC2) and ZNF198/LSD1/Co-REST/HDAC1 chromatin-modifying complexes. Cells with stable knockdown of SUZ12, an essential PRC2 subunit, upon HBx expression demethylate a CpG dinucleotide located adjacent to NF-κB/RelA half-site. This NF-κB/RelA site is in a CpG island downstream from EpCAM transcriptional start site (TSS). Chromatin immunoprecipitation (ChIP) assays demonstrate HBx-dependent RelA occupancy of NF-κB half-site, whereas RelA knockdown suppresses CpG demethylation and EpCAM expression. Tumor necrosis factor-α activates RelA, propagating demethylation to nearby CpG sites, shown by sodium bisulfite sequencing. RelA-dependent demethylation occurring upon HBx expression requires methyltrasferase EZH2, TET2 a key factor in cytosine demethylation and inactive DNMT3L, shown by knockdown assays and sodium bisulfite sequencing. Co-immunoprecipitations and sequential ChIP assays demonstrate that RelA in the presence of HBx forms a complex with EZH2, TET2 and DNMT3L, although the role of DNMT3L remains to be understood. Interestingly, the human EpCAM gene also has a CpG island downstream from its TSS, and a NF-κB-binding site flanked by CpGs. HepG2 cells derived from human HCC exhibit demethylation of these NF-κB-flanking CpG sites, and HBV replication propagates demethylation to nearby CpG sites. DLK

  9. Hepatitis B Virus X Protein Up-Regulates AKR1C1 Expression Through Nuclear Factor-Y in Human Hepatocarcinoma Cells.

    Science.gov (United States)

    Li, Kai; Ding, Shijia; Chen, Ke; Qin, Dongdong; Qu, Jialin; Wang, Sen; Sheng, Yanrui; Zou, Chengcheng; Chen, Limin; Tang, Hua

    2013-01-01

    The hepatitis B virus X (HBx) protein has long been recognized as an important transcriptional transactivator of several genes. Human aldo-keto reductase family 1, member C1 (AKR1C1), a member of the family of AKR1CS, is significantly increased in HBx-expressed cells. This study aimed to investigate the possible mechanism of HBx in regulating AKR1C1 expression in HepG2.2.15 cells and the role of AKR1C1 for HBV-induced HCC. RT-PCR was performed to detect AKR1C1 expression on mRNA level in HepG2 and HepG2.2.15 cell. The promoter activity of AKR1C1 was assayed by transient transfection and Dual-luciferase reporter assay system. The AKR1C1 promoter sequence was screened using the TFSEARCH database and the ALIBABA 2.0 software. The potential transcription factors binding sites were identified using 5' functional deletion analysis and site-directed mutagenesis. In this study, we found that HBx promoted AKR1C1 expression in HepG2.2.15 cells. Knockdown of HBx inhibited AKR1C1 activation. The role of HBx expression in regulating the promoter activity of human AKR1C1 gene was analyzed. The 5'functional deletion analysis identified that the region between -128 and -88 was the minimal promoter region of HBx to activate AKR1C1 gene expression. Site-directed mutagenesis studies suggested that nuclear factor-Y (NF-Y) plays an important role in this HBx-induced AKR1C1 activation. In HepG2.2.1.5 cell, HBx can promote AKR1C1 promoter activity and thus activates the basal transcription of AKR1C1 gene. This process is mediated by the transcription factor NF-Y. This study explored the mechanism for the regulation of HBV on AKR1C1 expression and has provided a new understanding of HBV-induced HCC.

  10. Biological and immunological characterization of recombinant Yellow Fever 17D Viruses expressing a Trypanosoma cruzi Amastigote Surface Protein-2 CD8+ T cell epitope at two distinct regions of the genome

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    Bonaldo Myrna C

    2011-03-01

    Full Text Available Abstract Background The attenuated Yellow fever (YF 17D vaccine virus is one of the safest and most effective viral vaccines administered to humans, in which it elicits a polyvalent immune response. Herein, we used the YF 17D backbone to express a Trypanosoma cruzi CD8+ T cell epitope from the Amastigote Surface Protein 2 (ASP-2 to provide further evidence for the potential of this virus to express foreign epitopes. The TEWETGQI CD8+ T cell epitope was cloned and expressed based on two different genomic insertion sites: in the fg loop of the viral Envelope protein and the protease cleavage site between the NS2B and NS3. We investigated whether the site of expression had any influence on immunogenicity of this model epitope. Results Recombinant viruses replicated similarly to vaccine virus YF 17D in cell culture and remained genetically stable after several serial passages in Vero cells. Immunogenicity studies revealed that both recombinant viruses elicited neutralizing antibodies to the YF virus as well as generated an antigen-specific gamma interferon mediated T-cell response in immunized mice. The recombinant viruses displayed a more attenuated phenotype than the YF 17DD vaccine counterpart in mice. Vaccination of a mouse lineage highly susceptible to infection by T. cruzi with a homologous prime-boost regimen of recombinant YF viruses elicited TEWETGQI specific CD8+ T cells which might be correlated with a delay in mouse mortality after a challenge with a lethal dose of T. cruzi. Conclusions We conclude that the YF 17D platform is useful to express T. cruzi (Protozoan antigens at different functional regions of its genome with minimal reduction of vector fitness. In addition, the model T. cruzi epitope expressed at different regions of the YF 17D genome elicited a similar T cell-based immune response, suggesting that both expression sites are useful. However, the epitope as such is not protective and it remains to be seen whether expression

  11. Extensive co-operation between the Epstein-Barr virus EBNA3 proteins in the manipulation of host gene expression and epigenetic chromatin modification.

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    Robert E White

    2010-11-01

    Full Text Available Epstein-Barr virus (EBV is able to drive the transformation of B-cells, resulting in the generation of lymphoblastoid cell lines (LCLs in vitro. EBV nuclear proteins EBNA3A and EBNA3C are necessary for efficient transformation, while EBNA3B is dispensable. We describe a transcriptome analysis of BL31 cells infected with a series of EBNA3-knockout EBVs, including one deleted for all three EBNA3 genes. Using Affymetrix Exon 1.0 ST microarrays analysed with the MMBGX algorithm, we have identified over 1000 genes whose regulation by EBV requires one of the EBNA3s. Remarkably, a third of the genes identified require more than one EBNA3 for their regulation, predominantly EBNA3C co-operating with either EBNA3B, EBNA3A or both. The microarray was validated by real-time PCR, while ChIP analysis of a selection of co-operatively repressed promoters indicates a role for polycomb group complexes. Targets include genes involved in apoptosis, cell migration and B-cell differentiation, and show a highly significant but subtle alteration in genes involved in mitosis. In order to assess the relevance of the BL31 system to LCLs, we analysed the transcriptome of a set of EBNA3B knockout (3BKO LCLs. Around a third of the genes whose expression level in LCLs was altered in the absence of EBNA3B were also altered in 3BKO-BL31 cell lines.Among these are TERT and TCL1A, implying that EBV-induced changes in the expression of these genes are not required for B-cell transformation. We also identify 26 genes that require both EBNA3A and EBNA3B for their regulation in LCLs. Together, this shows the complexity of the interaction between EBV and its host, whereby multiple EBNA3 proteins co-operate to modulate the behaviour of the host cell.

  12. Lab-Attenuated Rabies Virus Causes Abortive Infection and Induces Cytokine Expression in Astrocytes by Activating Mitochondrial Antiviral-Signaling Protein Signaling Pathway

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    Bin Tian

    2018-01-01

    Full Text Available Rabies is an ancient disease but remains endemic in most parts of the world and causes approximately 59,000 deaths annually. The mechanism through which the causative agent, rabies virus (RABV, evades the host immune response and infects the host central nervous system (CNS has not been completely elucidated thus far. Our previous studies have shown that lab-attenuated, but not wild-type (wt, RABV activates the innate immune response in the mouse and dog models. In this present study, we demonstrate that lab-attenuated RABV causes abortive infection in astrocytes, the most abundant glial cells in the CNS. Furthermore, we found that lab-attenuated RABV produces more double-stranded RNA (dsRNA than wt RABV, which is recognized by retinoic acid-inducible gene I (RIG-I or melanoma differentiation-associated protein 5 (MDA5. Activation of mitochondrial antiviral-signaling protein (MAVS, the common adaptor molecule for RIG-I and MDA5, results in the production of type I interferon (IFN and the expression of hundreds of IFN-stimulated genes, which suppress RABV replication and spread in astrocytes. Notably, lab-attenuated RABV replicates in a manner identical to that of wt RABV in MAVS−/− astrocytes. It was also found that lab-attenuated, but not wt, RABV induces the expression of inflammatory cytokines via the MAVS- p38/NF-κB signaling pathway. These inflammatory cytokines increase the blood–brain barrier permeability and thus enable immune cells and antibodies infiltrate the CNS parenchyma, resulting in RABV control and elimination. In contrast, wt RABV restricts dsRNA production and thus evades innate recognition by RIG-I/MDA5 in astrocytes, which could be one of the mechanisms by which wt RABV evades the host immune response in resident CNS cells. Our findings suggest that astrocytes play a critical role in limiting the replication of lab-attenuated RABV in the CNS.

  13. Baculovirus-expressed virus-like particle vaccine in combination with DNA encoding the fusion protein confers protection against respiratory syncytial virus.

    Science.gov (United States)

    Lee, Jong Seok; Kwon, Young-Man; Hwang, Hye Suk; Lee, Yu-Na; Ko, Eun-Ju; Yoo, Si-Eun; Kim, Min-Chul; Kim, Ki-Hye; Cho, Min Kyoung; Lee, Young-Tae; Lee, You Ri; Quan, Fu-Shi; Kang, Sang-Moo

    2014-10-07

    Respiratory syncytial virus (RSV) is a major viral agent causing significant morbidity and mortality in young infants and the elderly. There is no licensed vaccine against RSV and it is a high priority to develop a safe RSV vaccine. We determined the immunogenicity and protective efficacy of combined virus-like particle and DNA vaccines presenting RSV glycoproteins (Fd.VLP) in comparison with formalin inactivated RSV (FI-RSV). Immunization of mice with Fd.VLP induced higher ratios of IgG2a/IgG1 antibody responses compared to those with FI-RSV. Upon live RSV challenge, Fd.VLP and FI-RSV vaccines were similarly effective in clearing lung viral loads. However, FI-RSV immunized mice showed a substantial weight loss and high levels of T helper type 2 (Th2) cytokines as well as extensive lung histopathology and eosinophil infiltration. In contrast, Fd.VLP immunized mice did not exhibit Th2 type cytokines locally and systemically, which might contribute to preventing vaccine-associated RSV lung disease. These results indicate that virus-like particles in combination with DNA vaccines represent a potential approach for developing a safe and effective RSV vaccine. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Vectors expressing chimeric Japanese encephalitis dengue 2 viruses.

    Science.gov (United States)

    Wei, Y; Wang, S; Wang, X

    2014-01-01

    Vectors based on self-replicating RNAs (replicons) of flaviviruses are becoming powerful tool for expression of heterologous genes in mammalian cells and development of novel antiviral and anticancer vaccines. We constructed two vectors expressing chimeric viruses consisting of attenuated SA14-14-2 strain of Japanese encephalitis virus (JEV) in which the PrM/M-E genes were replaced fully or partially with those of dengue 2 virus (DENV-2). These vectors, named pJED2 and pJED2-1770 were transfected to BHK-21 cells and produced chimeric viruses JED2V and JED2-1770V, respectively. The chimeric viruses could be passaged in C6/36 but not BHK-21 cells. The chimeric viruses produced in C6/36 cells CPE 4-5 days after infection and RT-PCR, sequencing, immunofluorescence assay (IFA) and Western blot analysis confirmed the chimeric nature of produced viruses. The immunogenicity of chimeric viruses in mice was proved by detecting DENV-2 E protein-specific serum IgG antibodies with neutralization titer of 10. Successful preparation of infectious clones of chimeric JEV-DENV-2 viruses showed that JEV-based expression vectors are fully functional.

  15. Expression of the rice hoja blanca virus (RHBV) non-structural protein 3 (NS3) in Escherichia coli and its in situ localization in RHBV-infected rice tissues.

    Science.gov (United States)

    Muñoz, Miguel; Bolaños, Isela; Arrieta-Espinoza, Griselda; Espinoza, Ana M

    2004-09-01

    The non-structural NS3 protein gene from the rice hoja blanca virus (RHBV) was fused to the glutathione-S-transferase carboxilic end and expressed in Escherichia coli strain JM83. Large quantities of fusion protein were produced in insoluble form. The fusion protein was fractionated in SDS-PAGE and purified by electroelution, polyclonal antibodies were raised in rabbit and the antiserum was absorbed with bacterial crude extract. A band of similar size as that of NS3 protein was observed in Western blots using extracts from RHBV-infected rice plants. Immunoelectron microscopy with colloidal gold-labeled antibodies against NS3 protein and the viral nucleocapsid protein revealed in situ accumulation of NS3 protein in the cytoplasm but not in the viral inclusion bodies, vacuoles or chloroplasts of RHBV-infected plants, following the same pattern of distribution as the RHBV nucleocapsid protein.

  16. Infection of the upper respiratory tract of hamsters by the bovine parainfluenza virus type 3 BN-1 strain expressing enhanced green fluorescent protein.

    Science.gov (United States)

    Ohkura, Takashi; Minakuchi, Moeko; Sagai, Mami; Kokuho, Takehiro; Konishi, Misako; Kameyama, Ken-Ichiro; Takeuchi, Kaoru

    2015-02-01

    Bovine parainfluenza virus type 3 (BPIV3) is an important pathogen associated with bovine respiratory disease complex (BRDC). We have generated a recombinant BPIV3 expressing enhanced green fluorescent protein (rBPIV3-EGFP) based on the BN-1 strain isolated in Japan. After intranasal infection of hamsters with rBPIV3-EGFP, EGFP fluorescence was detected in the upper respiratory tract including the nasal turbinates, pharynx, larynx, and trachea. In the nasal turbinates, rBPIV3-EGFP attained high titers (>10(6) TCID50/g of tissue) 2-4 days after infection. Ciliated epithelial cells in the nasal turbinates and trachea were infected with rBPIV3-EGFP. Histopathological analysis indicated that mucosal epithelial cells in bronchi were shed by 6 days after infection, leaving non-ciliated cells, which may have increased susceptibility to bacterial infection leading to the development of BRDC. These data indicate that rBPIV3-EGFP infection of hamsters is a useful small animal model for studying the development of BPIV3-associated BRDC. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Concurrent alterations of RAGE, RECK, and MMP9 protein expression are relevant to Epstein-Barr virus infection, metastasis, and survival in nasopharyngeal carcinoma.

    Science.gov (United States)

    Zhou, Dong-Ni; Deng, Yan-Fei; Li, Rong-Hua; Yin, Ping; Ye, Chun-Sheng

    2014-01-01

    This study aimed to concurrently investigate the expressions of receptor for advanced glycation end products (RAGE), reversion inducing cysteine-rich protein with Kazal motifs (RECK) and matrix metalloproteinase 9 (MMP9) in nasopharyngeal carcinoma (NPC) and their correlations with clinicopathological properties. Using immunohistochemistry, we found that RECK expression was downregulated in NPC tissues compared with chronic nasopharyngitis (CNT) tissues, while RAGE and MMP9 expressions were upregulated. We further found that RECK expression level was inversely correlated with MMP9 expression level in NPC, whereas RAGE expression level was positively correlated with MMP9 expression level. Moreover, aberrant expressions of these proteins had a positive correlation with the titers of EBVCA-IgA, lymphatic metastasis, recurrence and survival. Together, these findings suggest that dysregulations of RECK and RAGE expressions may be collectively involved in tumor progression of NPC by regulating MMP9 expression and that they may be a good prognostic predictors for NPC.

  18. Comparative interactomics for virus-human protein-protein interactions: DNA viruses versus RNA viruses.

    Science.gov (United States)

    Durmuş, Saliha; Ülgen, Kutlu Ö

    2017-01-01

    Viruses are obligatory intracellular pathogens and completely depend on their hosts for survival and reproduction. The strategies adopted by viruses to exploit host cell processes and to evade host immune systems during infections may differ largely with the type of the viral genetic material. An improved understanding of these viral infection mechanisms is only possible through a better understanding of the pathogen-host interactions (PHIs) that enable viruses to enter into the host cells and manipulate the cellular mechanisms to their own advantage. Experimentally-verified protein-protein interaction (PPI) data of pathogen-host systems only became available at large scale within the last decade. In this study, we comparatively analyzed the current PHI networks belonging to DNA and RNA viruses and their human host, to get insights into the infection strategies used by these viral groups. We investigated the functional properties of human proteins in the PHI networks, to observe and compare the attack strategies of DNA and RNA viruses. We observed that DNA viruses are able to attack both human cellular and metabolic processes simultaneously during infections. On the other hand, RNA viruses preferentially interact with human proteins functioning in specific cellular processes as well as in intracellular transport and localization within the cell. Observing virus-targeted human proteins, we propose heterogeneous nuclear ribonucleoproteins and transporter proteins as potential antiviral therapeutic targets. The observed common and specific infection mechanisms in terms of viral strategies to attack human proteins may provide crucial information for further design of broad and specific next-generation antiviral therapeutics.

  19. Eradication of established HPV16-transformed tumours after immunisation with recombinant Semliki Forest virus expressing a fusion protein of E6 and E7

    NARCIS (Netherlands)

    Daemen, T; Riezebos-Brilman, A; Bungener, L; Regts, J; Dontje, B; Wischut, J

    2003-01-01

    Previously, we described the efficacy of immunisation with recombinant Semliki Forest virus (SFV), expressing the human papillomavirus 16 (HPV) oncoproteins E6 and E7, in inducing HPV-specific CTLs and anti-tumour responses. Recently, we developed a novel recombinant SFV construct encoding a

  20. Quantitative analysis of Nipah virus proteins released as virus-like particles reveals central role for the matrix protein

    Directory of Open Access Journals (Sweden)

    Eaton Bryan T

    2007-01-01

    Full Text Available Abstract Background Nipah virus (NiV is an emerging paramyxovirus distinguished by its ability to cause fatal disease in both animal and human hosts. Together with Hendra virus (HeV, they comprise the genus Henipavirus in the Paramyxoviridae family. NiV and HeV are also restricted to Biosafety Level-4 containment and this has hampered progress towards examining details of their replication and morphogenesis. Here, we have established recombinant expression systems to study NiV particle assembly and budding through the formation of virus-like particles (VLPs. Results When expressed by recombinant Modified Vaccinia virus Ankara (rMVA or plasmid transfection, individual NiV matrix (M, fusion (F and attachment (G proteins were all released into culture supernatants in a membrane-associated state as determined by sucrose density gradient flotation and immunoprecipitation. However, co-expression of F and G along with M revealed a shift in their distribution across the gradient, indicating association with M in VLPs. Protein release was also altered depending on the context of viral proteins being expressed, with F, G and nucleocapsid (N protein reducing M release, and N release dependent on the co-expression of M. Immunoelectron microscopy and density analysis revealed VLPs that were similar to authentic virus. Differences in the budding dynamics of NiV proteins were also noted between rMVA and plasmid based strategies, suggesting that over-expression by poxvirus may not be appropriate for studying the details of recombinant virus particle assembly and release. Conclusion Taken together, the results indicate that NiV M, F, and G each possess some ability to bud from expressing cells, and that co-expression of these viral proteins results in a more organized budding process with M playing a central role. These findings will aid our understanding of paramyxovirus particle assembly in general and could help facilitate the development of a novel vaccine

  1. HCVpro: Hepatitis C virus protein interaction database

    KAUST Repository

    Kwofie, Samuel K.

    2011-12-01

    It is essential to catalog characterized hepatitis C virus (HCV) protein-protein interaction (PPI) data and the associated plethora of vital functional information to augment the search for therapies, vaccines and diagnostic biomarkers. In furtherance of these goals, we have developed the hepatitis C virus protein interaction database (HCVpro) by integrating manually verified hepatitis C virus-virus and virus-human protein interactions curated from literature and databases. HCVpro is a comprehensive and integrated HCV-specific knowledgebase housing consolidated information on PPIs, functional genomics and molecular data obtained from a variety of virus databases (VirHostNet, VirusMint, HCVdb and euHCVdb), and from BIND and other relevant biology repositories. HCVpro is further populated with information on hepatocellular carcinoma (HCC) related genes that are mapped onto their encoded cellular proteins. Incorporated proteins have been mapped onto Gene Ontologies, canonical pathways, Online Mendelian Inheritance in Man (OMIM) and extensively cross-referenced to other essential annotations. The database is enriched with exhaustive reviews on structure and functions of HCV proteins, current state of drug and vaccine development and links to recommended journal articles. Users can query the database using specific protein identifiers (IDs), chromosomal locations of a gene, interaction detection methods, indexed PubMed sources as well as HCVpro, BIND and VirusMint IDs. The use of HCVpro is free and the resource can be accessed via http://apps.sanbi.ac.za/hcvpro/ or http://cbrc.kaust.edu.sa/hcvpro/. © 2011 Elsevier B.V.

  2. Functional Carboxy-Terminal Fluorescent Protein Fusion to Pseudorabies Virus Small Capsid Protein VP26.

    Science.gov (United States)

    Hogue, Ian B; Jean, Jolie; Esteves, Andrew D; Tanneti, Nikhila S; Scherer, Julian; Enquist, Lynn W

    2018-01-01

    Fluorescent protein fusions to herpesvirus capsids have proven to be a valuable method to study virus particle transport in living cells. Fluorescent protein fusions to the amino terminus of small capsid protein VP26 are the most widely used method to visualize pseudorabies virus (PRV) and herpes simplex virus (HSV) particles in living cells. However, these fusion proteins do not incorporate to full occupancy and have modest effects on virus replication and pathogenesis. Recent cryoelectron microscopy studies have revealed that herpesvirus small capsid proteins bind to capsids via their amino terminus, whereas the carboxy terminus is unstructured and therefore may better tolerate fluorescent protein fusions. Here, we describe a new recombinant PRV expressing a carboxy-terminal VP26-mCherry fusion. Compared to previously characterized viruses expressing amino-terminal fusions, this virus expresses more VP26 fusion protein in infected cells and incorporates more VP26 fusion protein into virus particles, and individual virus particles exhibit brighter red fluorescence. We performed single-particle tracking of fluorescent virus particles in primary neurons to measure anterograde and retrograde axonal transport, demonstrating the usefulness of this novel VP26-mCherry fusion for the study of viral intracellular transport.IMPORTANCE Alphaherpesviruses are among the very few viruses that are adapted to invade the mammalian nervous system. Intracellular transport of virus particles in neurons is important, as this process underlies both mild peripheral nervous system infection and severe spread to the central nervous system. VP26, the small capsid protein of HSV and PRV, was one of the first herpesvirus proteins to be fused to a fluorescent protein. Since then, these capsid-tagged virus mutants have become a powerful tool to visualize and track individual virus particles. Improved capsid tags will facilitate fluorescence microscopy studies of virus particle intracellular

  3. Leptospira Protein Expression During Infection

    Science.gov (United States)

    We are characterizing protein expression in vivo during experimental leptospirosis using immunofluorescence microscopy. Coding regions for several proteins were identified through analysis of Leptospira interrogans serovar Copenhageni and L. borgpetersenii serovar Hardjo genomes. In addition, codi...

  4. Motor-coordination-dependent learning, more than others, is impaired in transgenic mice expressing pseudorabies virus immediate-early protein IE180.

    Directory of Open Access Journals (Sweden)

    Juan C López-Ramos

    Full Text Available The cerebellum in transgenic mice expressing pseudorabies virus immediate-early protein IE180 (TgIE96 was substantially diminished in size, and its histoarchitecture was severely disorganized, resulting in severe ataxia. TgIE96 mice can therefore be used as an experimental model to study the involvement of cerebellar circuits in different learning tasks. The performance of three-month-old TgIE96 mice was studied in various behavioral tests, including associative learning (classical eyeblink conditioning, object recognition, spatial orientation (water maze, startle response and prepulse inhibition, and passive avoidance, and compared with that of wild-type mice. Wild-type and TgIE96 mice presented similar reflexively evoked eyeblinks, and acquired classical conditioned eyelid responses with similar learning curves for both trace and delay conditioning paradigms. The two groups of mice also had similar performances during the object recognition test. However, they showed significant differences for the other three tests included in this study. Although both groups of animals were capable of swimming, TgIE96 mice failed to learn the water maze task during the allowed time. The startle response to a severe tone was similar in both control and TgIE96 mice, but the latter were unable to produce a significant prepulse inhibition. TgIE96 mice also presented evident deficits for the proper accomplishment of a passive avoidance test. These results suggest that the cerebellum is not indispensable for the performance of classical eyeblink conditioning and for object recognition tasks, but seems to be necessary for the proper performance of water maze, prepulse inhibition, and passive avoidance tests.

  5. Retraction: "An enhanced transient expression system in plants based on suppression of gene silencing by the p19 protein of tomato bushy stunt virus".

    Science.gov (United States)

    2015-11-01

    Retracted: An enhanced transient expression system in plants based on suppression of gene silencing by the p19 protein of tomato bushy stunt virus Volume 33, Issue 5, 949–956, Article first published online: 28 February 2003. The above article, first published online on 28 February 2003 in Wiley Online Library (wileyonlinelibrary.com), and in volume 33, pp. 949–956, has been retracted by agreement between the authors, the journal Editor in Chief, Christoph Benning, and John Wiley & Sons Ltd.This notice updates and replaces a recent correction notice, published on 8 June 2015.In the above article, it has recently been noted that the original Figure 3b in this paper was assembled incorrectly and included image duplications. As the original data are no longer available for assembly of a corrected figure, the experiment was repeated, in agreement with the editors, by co-author S. Rivas. The data from the repeated experiment, presented below together with the original figure legend, lead to the same interpretation and conclusions as in the original paper.Since publication of the above notice the corresponding author has become aware of additional image duplications involving the loading control lanes of Figures 2g, 3a, 4e and 4f. The authors accept that integrity of the scientific literature is compromised by the data manipulation and, for that reason, they wish to retract the article. However, researchers wishing to use the method described in this paper can still obtain the necessary clones from the corresponding author (dcb40@cam.ac.uk). The authors apologise for having allowed this flawed article to be published.

  6. Vaccination of mice with plasmids expressing processed capsid protein of foot-and-mouth disease virus - Importance of dominant and subdominant epitopes for antigenicity and protection

    DEFF Research Database (Denmark)

    Frimann, Tine; Barfoed, Annette Malene; Aasted, Bent

    2007-01-01

    example of a dominant and variable site. This variability is a problem when designing vaccines against this disease, because it necessitates a close match between vaccine strain and virus in an outbreak. We have introduced a series of mutations into viral capsid proteins with the aim of selectively...... as compared to mice vaccinated with wild type epitopes. Most of the modifications did not adversely affect the ability of the plasmids to induce complete protection of mice against homologous challenge....

  7. Radioimmunoassay of measles virus hemagglutinin protein G

    Energy Technology Data Exchange (ETDEWEB)

    Lund, G.A.; Salmi, A.A. (Turku Univ. (Finland))

    1982-08-01

    Guinea pig and rabbit antisera from animals immunized with purified measles virus hemagglutinin (G) protein were used to establish a solid-phase four-layer radioimmunoassay for quantitative measurement of the G protein. The sensitivity of the assay was 2 ng of purified G protein, and 200 ..mu..g of protein from uninfected Vero cells neither decreased the sensitivity nor reacted non-specifically in the assay. Radioimmunoassay standard dose-response curves were established and unknown values interpolated from these using the logit program of a desktop computer. Using this procedure, a measles virus growth curve in infected Vero cells was determined by measurement of G protein production. Under these same conditions, hemagglutination was not sensitive enough to detect early hemagglutinin production. Viral antigens in canine distemper virus, Newcastle disease virus, parainfluenza viruses 1-4, simian virus 5, and respiratory syncytial virus-infected cell lysates did not cross-react in the radioimmunoassay. A small degree of cross-reactivity was detected with mumps viral antigens, both with Vero cell-derived (wild-type strain) and egg-derived (Enders strain) purified virus preparations and with a cell lysate antigen prepared from wild-type mumps virus-infected Vero cells.

  8. Expression of a recombinant Human papillomavirus 16 E6GT oncoprotein fused to N- and C-termini of Potato virus X coat protein in Nicotiana benthamiana

    Czech Academy of Sciences Publication Activity Database

    Čeřovská, Noemi; Moravec, Tomáš; Hoffmeisterová, Hana; Plchová, Helena; Synková, Helena; Poláková, I.; Dušková, M.; Šmahel, M.

    2013-01-01

    Roč. 113, č. 1 (2013), s. 81-90 ISSN 0167-6857 R&D Projects: GA ČR GA521/09/1525; GA ČR(CZ) GAP501/12/1761 Institutional research plan: CEZ:AV0Z50380511 Keywords : Transient expression * Molecular farming * Potato virus X Subject RIV: EE - Microbiology, Virology Impact factor: 2.612, year: 2013

  9. Development of transgenic papayas expressing the coat protein gene from a Brazilian isolate of Papaya ringspot virus (PRSV) = Desenvolvimento de mamoeiros transgênicos resistentes a vírus expressando o gene da capa protéica de um isolado brasileiro de Papaya ringspot virus

    NARCIS (Netherlands)

    Souza, M.T.; Níckel, O.; Gonsalves, D.

    2005-01-01

    Translatable and nontranslatable versions of the coat protein (cp) gene of a Papaya ringspot virus (PRSV) isolate collected in the state of Bahia, Brazil, were engineered for expression in Sunrise and Sunset Solo varieties of papaya (Carica papaya). The biolistic system was used to transform

  10. Expression and structural properties of a chimeric protein based on the ectodomains of E1 and E2 hepatitis C virus envelope glycoproteins

    OpenAIRE

    Tello, Daniel; Rodríguez-Rodríguez, Mar; Yélamos, Belén; Gómez-Gutiérrez, Julián; Ortega, Sara; Pacheco, Beatriz; Peterson, Darrell L.; Gavilanes, Francisco

    2010-01-01

    Hepatitis C virus encodes two enveloped glycoproteins, E1 and E2, which are involved in viral attachment and entry into target cells. We have obtained in insect cells infected by recombinant baculovirus a chimeric secreted recombinant protein, E1341E2661, containing the ectodomains of E1 and E2. The described procedure allows the purification of approximately 2 mg of protein from 1 L of culture media. Sedimentation velocity experiments and SDS-PAGE in the absence of reducing agents indicate t...

  11. Immunogenicity of an adeno-vector vaccine expressing the F protein of a respiratory syncytial virus manufactured from serum-free suspension culture.

    Science.gov (United States)

    Shao, Hsiao-Yun; Hsu, Huai-Sheng; Yu, Shu-Ling; Wu, Shang-Rung; Hu, Kai-Chieh; Chang, Ching-Kun; Liu, Chia-Chyi; Chow, Yen-Hung

    2016-06-01

    We have developed an efficient cell culture process to scale up the production of a recombinant adenovirus that expresses the membrane-trunked fusion protein of respiratory syncytial virus (RSV; Ad-F0ΔTM). Adherent cells of human embryonic kidney (HEK) 293-derived cell, 293A, which supports the production of E1/E3-deleted Ad-F0ΔTM when cultured in the presence of fetal bovine serum (FBS), were adapted to suspension growth under serum-free medium. In doing so, we studied the immunogenicity of Ad-F0ΔTMsus, which propagated in a bioreactor that was cultured with serum-free suspension of 293A, in comparison with Ad-F0ΔTMadh, which was produced from parental 293A cells that were adherently cultured in medium containing FBS. The size and morphology of Ad-F0ΔTMsus and Ad-F0ΔTMadh virions were identical upon inspection with electron microscopy. The results showed that anti-F IgG and RSV-neutralizing titer were raised in the serum of both mice that were intranasally immunized twice with Ad-F0ΔTMsus or Ad-F0ΔTMadh at two-week injection intervals. Furthermore, the immune responses persisted for six months after vaccination. Activation of F protein-specific CD8(+) T cell's epitope associated IFN-ɣ and IL-4 was induced in both Ad-F0ΔTMsus- and Ad-F0ΔTMadh, but not in Ad-LacZsus, -immunized mouse splenocytes. No vaccine-enhanced lung inflammation, airway mucus occlusion or eosinophils infiltration were observed in Ad-immunized mice followed by RSV challenge; however, these symptoms were observed following immunization with formalin-inactivated RSV vaccine. These results indicate that the safety and potency of Ad-F0ΔTM produced from either adherent cells or suspension and serum-free cells are the same. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Concurrent alterations of RAGE, RECK, and MMP9 protein expression are relevant to Epstein-Barr virus infection, metastasis, and survival in nasopharyngeal carcinoma

    OpenAIRE

    Zhou, Dong-Ni; Deng, Yan-Fei; Li, Rong-Hua; Yin, Ping; Ye, Chun-Sheng

    2014-01-01

    This study aimed to concurrently investigate the expressions of receptor for advanced glycation end products (RAGE), reversion inducing cysteine-rich protein with Kazal motifs (RECK) and matrix metalloproteinase 9 (MMP9) in nasopharyngeal carcinoma (NPC) and their correlations with clinicopathological properties. Using immunohistochemistry, we found that RECK expression was downregulated in NPC tissues compared with chronic nasopharyngitis (CNT) tissues, while RAGE and MMP9 expressions were u...

  13. Validation of reference genes for quantifying changes in gene expression in virus-infected tobacco.

    Science.gov (United States)

    Baek, Eseul; Yoon, Ju-Yeon; Palukaitis, Peter

    2017-10-01

    To facilitate quantification of gene expression changes in virus-infected tobacco plants, eight housekeeping genes were evaluated for their stability of expression during infection by one of three systemically-infecting viruses (cucumber mosaic virus, potato virus X, potato virus Y) or a hypersensitive-response-inducing virus (tobacco mosaic virus; TMV) limited to the inoculated leaf. Five reference-gene validation programs were used to establish the order of the most stable genes for the systemically-infecting viruses as ribosomal protein L25 > β-Tubulin > Actin, and the least stable genes Ubiquitin-conjugating enzyme (UCE) genes were EF1α > Cysteine protease > Actin, and the least stable genes were GAPDH genes, three defense responsive genes were examined to compare their relative changes in gene expression caused by each virus. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Recombinant human adenovirus-5 expressing capsid proteins of Indian vaccine strains of foot-and-mouth disease virus elicits effective antibody response in cattle.

    Science.gov (United States)

    Sreenivasa, B P; Mohapatra, J K; Pauszek, S J; Koster, M; Dhanya, V C; Tamil Selvan, R P; Hosamani, M; Saravanan, P; Basagoudanavar, Suresh H; de Los Santos, T; Venkataramanan, R; Rodriguez, L L; Grubman, M J

    2017-05-01

    Recombinant adenovirus-5 vectored foot-and-mouth disease constructs (Ad5- FMD) were made for three Indian vaccine virus serotypes O, A and Asia 1. Constructs co-expressing foot-and- mouth disease virus (FMDV) capsid and viral 3C protease sequences, were evaluated for their ability to induce a neutralizing antibody response in indigenous cattle (Bos indicus). Purified Ad5-FMD viruses were inoculated in cattle as monovalent (5×109 pfu/animal) or trivalent (5×109 pfu/animal per serotype) vaccines. Animals vaccinated with monovalent Ad5-FMD vaccines were boosted 63days later with the same dose. After primary immunization, virus neutralization tests (VNT) showed seroconversion in 83, 67 and 33% of animals vaccinated with Ad5-FMD O, A and Asia 1, respectively. Booster immunization elicited seroconversion in all of the animals (100%) in the monovalent groups. When used in a trivalent form, the Ad5-FMD vaccine induced neutralizing antibodies in only 33, 50 and 16% of animals against serotypes O, A and Asia 1, respectively on primo-vaccination, and titers were significantly lower than when the same vectors were used in monovalent form. Neutralizing antibody titers differed by serotype for both Ad5-FMD monovalent and trivalent vaccines, with Asia 1 serotype inducing the lowest titers. Antibody response to Ad5 vector in immunized cattle was also assessed by VNT. It appeared that the vector immunity did not impact the recall responses to expressed FMDV antigens on booster immunization. In summary, the study suggested that the recombinant Ad5-FMD vaccine has a potential use in monovalent form, while its application in multivalent form is not currently encouraging. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Virus-derived transgenes expressing hairpin RNA give immunity to Tobacco mosaic virus and Cucumber mosaic virus

    Directory of Open Access Journals (Sweden)

    Liu Yong

    2011-01-01

    Full Text Available Abstract Background An effective method for obtaining resistant transgenic plants is to induce RNA silencing by expressing virus-derived dsRNA in plants and this method has been successfully implemented for the generation of different plant lines resistant to many plant viruses. Results Inverted repeats of the partial Tobacco mosaic virus (TMV movement protein (MP gene and the partial Cucumber mosaic virus (CMV replication protein (Rep gene were introduced into the plant expression vector and the recombinant plasmids were transformed into Agrobacterium tumefaciens. Agrobacterium-mediated transformation was carried out and three transgenic tobacco lines (MP16-17-3, MP16-17-29 and MP16-17-58 immune to TMV infection and three transgenic tobacco lines (Rep15-1-1, Rep15-1-7 and Rep15-1-32 immune to CMV infection were obtained. Virus inoculation assays showed that the resistance of these transgenic plants could inherit and keep stable in T4 progeny. The low temperature (15℃ did not influence the resistance of transgenic plants. There was no significant correlation between the resistance and the copy number of the transgene. CMV infection could not break the resistance to TMV in the transgenic tobacco plants expressing TMV hairpin MP RNA. Conclusions We have demonstrated that transgenic tobacco plants expressed partial TMV movement gene and partial CMV replicase gene in the form of an intermolecular intron-hairpin RNA exhibited complete resistance to TMV or CMV infection.

  16. HCVpro: hepatitis C virus protein interaction database.

    Science.gov (United States)

    Kwofie, Samuel K; Schaefer, Ulf; Sundararajan, Vijayaraghava S; Bajic, Vladimir B; Christoffels, Alan

    2011-12-01

    It is essential to catalog characterized hepatitis C virus (HCV) protein-protein interaction (PPI) data and the associated plethora of vital functional information to augment the search for therapies, vaccines and diagnostic biomarkers. In furtherance of these goals, we have developed the hepatitis C virus protein interaction database (HCVpro) by integrating manually verified hepatitis C virus-virus and virus-human protein interactions curated from literature and databases. HCVpro is a comprehensive and integrated HCV-specific knowledgebase housing consolidated information on PPIs, functional genomics and molecular data obtained from a variety of virus databases (VirHostNet, VirusMint, HCVdb and euHCVdb), and from BIND and other relevant biology repositories. HCVpro is further populated with information on hepatocellular carcinoma (HCC) related genes that are mapped onto their encoded cellular proteins. Incorporated proteins have been mapped onto Gene Ontologies, canonical pathways, Online Mendelian Inheritance in Man (OMIM) and extensively cross-referenced to other essential annotations. The database is enriched with exhaustive reviews on structure and functions of HCV proteins, current state of drug and vaccine development and links to recommended journal articles. Users can query the database using specific protein identifiers (IDs), chromosomal locations of a gene, interaction detection methods, indexed PubMed sources as well as HCVpro, BIND and VirusMint IDs. The use of HCVpro is free and the resource can be accessed via http://apps.sanbi.ac.za/hcvpro/ or http://cbrc.kaust.edu.sa/hcvpro/. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. The vaccinia virus E6 protein influences virion protein localization during virus assembly

    Energy Technology Data Exchange (ETDEWEB)

    Condit, Richard C., E-mail: condit@mgm.ufl.edu; Moussatche, Nissin

    2015-08-15

    Vaccinia virus mutants in which expression of the virion core protein gene E6R is repressed are defective in virion morphogenesis. E6 deficient infections fail to properly package viroplasm into viral membranes, resulting in an accumulation of empty immature virions and large aggregates of viroplasm. We have used immunogold electron microscopy and immunofluorescence confocal microscopy to assess the intracellular localization of several virion structural proteins and enzymes during E6R mutant infections. We find that during E6R mutant infections virion membrane proteins and virion transcription enzymes maintain a normal localization within viral factories while several major core and lateral body proteins accumulate in aggregated virosomes. The results support a model in which vaccinia virions are assembled from at least three substructures, the membrane, the viroplasm and a “pre-nucleocapsid”, and that the E6 protein is essential for maintaining proper localization of the seven-protein complex and the viroplasm during assembly. - Highlights: • Mutation of E6 disrupts association of viral membranes with viral core proteins • Mutation of E6 does not perturb viral membrane biosynthesis • Mutation of E6 does not perturb localization of viral transcription enzymes • Mutation of E6 causes mis-localization and aggregation of viral core proteins • Vaccinia assembly uses three subassemblies: membranes, viroplasm, prenucleocapsid.

  18. Expression of VP1 protein of serotype A and O of foot-and-mouth disease virus in transgenic sunnhemp plants and its immunogenicity for guinea pigs.

    Science.gov (United States)

    Rao, J P; Agrawal, P; Mohammad, R; Rao, S K; Reddy, G R; Dechamma, H J; S Suryanarayana, V V

    2012-01-01

    Recently, transgenic plants expressing immunogenic proteins of foot-and-mouth disease virus (FMDV) have been used as oral or parenteral vaccines against foot-and-mouth disease (FMD). They exhibit advantages like cost effectiveness, absence of processing, thermostability, and easy oral application. FMDV VP1 protein of single serotype has been mostly used as immunogen. Here we report the development of a bivalent vaccine with tandem-linked VP1 proteins of two serotypes, A and O, present in transgenic forage crop Crotalaria juncea. The expression of the bivalent protein in the transgenic plants was confirmed by Western blot analysis. Guinea pig reacted to orally or parenterally applied vaccine by humoral as well as cell-mediated immune responses including serum antibodies and stimulated lymphocytes, respectively. The vaccine protected the animals against a challenge with the virus of serotype A as well as O. This is the first report on the development of a bivalent FMD vaccine using a forage crop. foot-and-mouth disease; sunnhemp; Agrobacterium tumefaciens; FMDV-VP1 gene; serotype O and A; in planta transformation; transgenic plants; bivalent vaccine.

  19. In vitro expression of native H5 and N1 genes of avian influenza virus by using Green Fluorescent Protein as reporter

    Directory of Open Access Journals (Sweden)

    Risza Hartawan

    2011-10-01

    Full Text Available The hemagglutinin and neuraminidase are important immunogen of avian influenza virus that are suitable for recombinant experimentation. However, both genes have been experienced rapid mutation resulting in diverse variety of genotypes. Hence, gene expression in recombinant systems will be difficult to predict. The objective of the study was to examine expression level of H5 and N1 genes from a field isolate by cloning the genes into expression vector pEGFP-C1. Two clones respresenting fulllength of H5 and N1 gene in plasmid pEGFP-C1 were transfected into chicken embryo fibroblasts (CEF, rabbit kidney (RK13 and African green monkey kidney (VERO cells using Lipofectamine ‘Plus’ reagent. The experiment showed level of gene expression in the VERO cell was higher than in the RK13 and CEF cells. Observations using fluorescent microscopy and Western blotting revealed that the N1 gene was expressed better in all cells compared to the H5 gene.

  20. Epstein - Barr virus transforming protein LMP-1 alters B cells gene expression by promoting accumulation of the oncoprotein ΔNp73α.

    Directory of Open Access Journals (Sweden)

    Rosita Accardi

    2013-03-01

    Full Text Available Many studies have proved that oncogenic viruses develop redundant mechanisms to alter the functions of the tumor suppressor p53. Here we show that Epstein-Barr virus (EBV, via the oncoprotein LMP-1, induces the expression of ΔNp73α, a strong antagonist of p53. This phenomenon is mediated by the LMP-1 dependent activation of c-Jun NH2-terminal kinase 1 (JNK-1 which in turn favours the recruitment of p73 to ΔNp73α promoter. A specific chemical inhibitor of JNK-1 or silencing JNK-1 expression strongly down-regulated ΔNp73α mRNA levels in LMP-1-containing cells. Accordingly, LMP-1 mutants deficient to activate JNK-1 did not induce ΔNp73α accumulation. The recruitment of p73 to the ΔNp73α promoter correlated with the displacement of the histone-lysine N-methyltransferase EZH2 which is part of the transcriptional repressive polycomb 2 complex. Inhibition of ΔNp73α expression in lymphoblastoid cells (LCLs led to the stimulation of apoptosis and up-regulation of a large number of cellular genes as determined by whole transcriptome shotgun sequencing (RNA-seq. In particular, the expression of genes encoding products known to play anti-proliferative/pro-apoptotic functions, as well as genes known to be deregulated in different B cells malignancy, was altered by ΔNp73α down-regulation. Together, these findings reveal a novel EBV mechanism that appears to play an important role in the transformation of primary B cells.

  1. The C-terminal end of parainfluenza virus 5 NP protein is important for virus-like particle production and M-NP protein interaction.

    Science.gov (United States)

    Schmitt, Phuong Tieu; Ray, Greeshma; Schmitt, Anthony P

    2010-12-01

    Enveloped virus particles are formed by budding from infected-cell membranes. For paramyxoviruses, viral matrix (M) proteins are key drivers of virus assembly and budding. However, other paramyxovirus proteins, including glycoproteins, nucleocapsid (NP or N) proteins, and C proteins, are also important for particle formation in some cases. To investigate the role of NP protein in parainfluenza virus 5 (PIV5) particle formation, NP protein truncation and substitution mutants were analyzed. Alterations near the C-terminal end of NP protein completely disrupted its virus-like particle (VLP) production function and significantly impaired M-NP protein interaction. Recombinant viruses with altered NP proteins were generated, and these viruses acquired second-site mutations. Recombinant viruses propagated in Vero cells acquired mutations that mainly affected components of the viral polymerase, while recombinant viruses propagated in MDBK cells acquired mutations that mainly affected the viral M protein. Two of the Vero-propagated viruses acquired the same mutation, V/P(S157F), found previously to be responsible for elevated viral gene expression induced by a well-characterized variant of PIV5, P/V-CPI(-). Vero-propagated viruses caused elevated viral protein synthesis and spread rapidly through infected monolayers by direct cell-cell fusion, bypassing the need to bud infectious virions. Both Vero- and MDBK-propagated viruses exhibited infectivity defects and altered polypeptide composition, consistent with poor incorporation of viral ribonucleoprotein complexes (RNPs) into budding virions. Second-site mutations affecting M protein restored interaction with altered NP proteins in some cases and improved VLP production. These results suggest that multiple avenues are available to paramyxoviruses for overcoming defects in M-NP protein interaction.

  2. Ekspresi Rekombinan Gen Protein Selubung Pepper vein yellows virus

    Directory of Open Access Journals (Sweden)

    Rita Kurnia Apindiati

    2015-09-01

    Full Text Available Pepper vein yellows virus (PeVYV isolate from Bali have been identified from pepper plants with chlorosis symptoms. Specific antiserum of PeVYV had not available yet commercially. One of the advance techniques in providing a source of abundant antigen for antiserum production is through molecular approach by overexpressed the coat protein gene in suitable bacterial expression system. PeVYV coat protein gene of ~650 bp in size was amplified using specific primers, then was cloned into pQE30 expression vector and was over expressed in E. coli strain M15 [pREP4]. SDS-PAGE analysis showed that the recombinant coat protein gene of PeVYV was successfully expressed protein band with size of ~25 kDa at 6 hours after induction by 0.5 mM IPTG on 37 °C.

  3. Cloning and expression of antiviral/ribosome-inactivating protein ...

    Indian Academy of Sciences (India)

    2008-02-02

    Feb 2, 2008 ... The ORF was cloned into an expression vector and expressed in E. coli as a fusion protein of ∼78 kDa. The cleaved and purified recombinant BBAP1 exhibited ribosome-inhibiting rRNA -glycosidase activity, and imparted a high level of resistance against the tobacco mosaic virus (TMV).

  4. Elevated Dengue Virus Nonstructural Protein 1 Serum Levels and Altered Toll-Like Receptor 4 Expression, Nitric Oxide, and Tumor Necrosis Factor Alpha Production in Dengue Hemorrhagic Fever Patients

    Directory of Open Access Journals (Sweden)

    Denise Maciel Carvalho

    2014-01-01

    Full Text Available Background. During dengue virus (DV infection, monocytes produce tumor necrosis factor alpha (TNF-α and nitric oxide (NO which might be critical to immunopathogenesis. Since intensity of DV replication may determine clinical outcomes, it is important to know the effects of viral nonstructural protein 1 (NS1 on innate immune parameters of infected patients. The present study investigates the relationships between dengue virus nonstructural protein 1 (NS1 serum levels and innate immune response (TLR4 expression and TNF-α/NO production of DV infected patients presenting different clinical outcomes. Methodology/Principal Findings. We evaluated NO, NS1 serum levels (ELISA, TNF-α production by peripheral blood mononuclear cells (PBMCs, and TLR4 expression on CD14+ cells from 37 dengue patients and 20 healthy controls. Early in infection, increased expression of TLR4 in monocytes of patients with dengue fever (DF was detected compared to patients with dengue hemorrhagic fever (DHF. Moreover, PBMCs of DHF patients showed higher NS1 and lower NO serum levels during the acute febrile phase and a reduced response to TLR4 stimulation by LPS (with a reduced TNF-α production when compared to DF patients. Conclusions/Significance. During DV infection in humans, some innate immune parameters change, depending on the NS1 serum levels, and phase and severity of the disease which may contribute to development of different clinical outcomes.

  5. Solenopsis invicta virus 3: mapping of structural proteins, ribosomal frameshifting, and similarities to Acyrthosiphon pisum virus and Kelp fly virus.

    Directory of Open Access Journals (Sweden)

    Steven M Valles

    Full Text Available Solenopsis invicta virus 3 (SINV-3 is a positive-sense single-stranded RNA virus that infects the red imported fire ant, Solenopsis invicta. We show that the second open reading frame (ORF of the dicistronic genome is expressed via a frameshifting mechanism and that the sequences encoding the structural proteins map to both ORF2 and the 3' end of ORF1, downstream of the sequence that encodes the RNA-dependent RNA polymerase. The genome organization and structural protein expression strategy resemble those of Acyrthosiphon pisum virus (APV, an aphid virus. The capsid protein that is encoded by the 3' end of ORF1 in SINV-3 and APV is predicted to have a jelly-roll fold similar to the capsid proteins of picornaviruses and caliciviruses. The capsid-extension protein that is produced by frameshifting, includes the jelly-roll fold domain encoded by ORF1 as its N-terminus, while the C-terminus encoded by the 5' half of ORF2 has no clear homology with other viral structural proteins. A third protein, encoded by the 3' half of ORF2, is associated with purified virions at sub-stoichiometric ratios. Although the structural proteins can be translated from the genomic RNA, we show that SINV-3 also produces a subgenomic RNA encoding the structural proteins. Circumstantial evidence suggests that APV may also produce such a subgenomic RNA. Both SINV-3 and APV are unclassified picorna-like viruses distantly related to members of the order Picornavirales and the family Caliciviridae. Within this grouping, features of the genome organization and capsid domain structure of SINV-3 and APV appear more similar to caliciviruses, perhaps suggesting the basis for a "Calicivirales" order.

  6. Development of Virus-Induced Gene Expression and Silencing Vector Derived from Grapevine Algerian Latent Virus.

    Science.gov (United States)

    Park, Sang-Ho; Choi, Hoseong; Kim, Semin; Cho, Won Kyong; Kim, Kook-Hyung

    2016-08-01

    Grapevine Algerian latent virus (GALV) is a member of the genus Tombusvirus in the Tombusviridae and infects not only woody perennial grapevine plant but also herbaceous Nicotiana benthamiana plant. In this study, we developed GALV-based gene expression and virus-induced gene silencing (VIGS) vectors in N. benthamiana. The GALV coat protein deletion vector, pGMG, was applied to express the reporter gene, green fluorescence protein (GFP), but the expression of GFP was not detected due to the necrotic cell death on the infiltrated leaves. The p19 silencing suppressor of GALV was engineered to inactivate its expression and GFP was successfully expressed with unrelated silencing suppressor, HC-Pro, from soybean mosaic virus. The pGMG vector was used to knock down magnesium chelatase (ChlH) gene in N. benthamaina and the silencing phenotype was clearly observed on systemic leaves. Altogether, the GALV-derived vector is expected to be an attractive tool for useful gene expression and VIGS vectors in grapevine as well as N. benthamiana.

  7. Construction and characterization of recombinant human adenovirus type 5 expressing foot-and-mouth disease virus capsid proteins of Indian vaccine strain, O/IND/R2/75

    Directory of Open Access Journals (Sweden)

    Ramesh Kumar

    2015-02-01

    Full Text Available Aim: Generation of recombinant human adenovirus type 5 expressing foot-and-mouth disease virus (FMDV capsid protein genes along with full-length 2B, 3B and 3Cpro and its characterization. Materials and Methods: FMD viral RNA isolation, cDNA synthesis, and polymerase chain reaction were performed to synthesize expression cassettes (P1-2AB3BCwt and P1-2AB3BCm followed by cloning in pShuttle-CMV vector. Chemically competent BJ5183-AD-1 cells were transformed with the recombinant pShuttle-CMV to produce recombinant adenoviral plasmids. HEK-293 cells were transfected with the recombinant adenoviral plasmids to generate recombinant adenoviruses (hAd5/P1-2AB3BCwt and hAd5/P1-2AB3BCm. Expression of the target proteins was analyzed by sandwich ELISA and indirect immunofluorescence assay. The recombinant adenoviruses were purified and concentrated by CsCl density gradient ultracentrifugation. Growth kinetics and thermostability of the recombinant adenoviruses were compared with that of non-recombinant replication-defective adenovirus (dAd5. Results: The recombinant adenoviruses containing capsid protein genes of the FMDV O/IND/R2/75 were generated and amplified in HEK-293 cells. The titer of the recombinant adenoviruses was approximately 108, 109.5 and 1011 TCID50/ml in supernatant media, cell lysate and CsCl purified preparation, respectively. Expression of the FMDV capsid protein was detectable in sandwich ELISA and confirmed by immunofluorescence assay. Growth kinetics of the recombinant adenoviruses did not reveal a significant difference when compared with that of dAd5. A decrement of up to 10-fold at 4°C and 21-fold at 37°C was recorded in the virus titers during 60 h incubation period and found to be statistically significant (p<0.01. Conclusion: Recombinant adenoviruses expressing capsid proteins of the FMDV O/IND/R2/75 were constructed and produced in high titers. In vitro expression of the target proteins in the adenovirus vector system was

  8. Analysis of hepatitis C virus core/NS5A protein co-localization using novel cell culture systems expressing core-NS2 and NS5A of genotypes 1-7

    DEFF Research Database (Denmark)

    Galli, Andrea; Scheel, Troels K H; Prentoe, Jannick C

    2013-01-01

    Hepatitis C virus (HCV) is an important human pathogen infecting hepatocytes. With the advent of infectious cell culture systems, the HCV particle assembly and release processes are finally being uncovered. The HCV core and NS5A proteins co-localize on cytoplasmic lipid droplets (cLDs) or on the ......Hepatitis C virus (HCV) is an important human pathogen infecting hepatocytes. With the advent of infectious cell culture systems, the HCV particle assembly and release processes are finally being uncovered. The HCV core and NS5A proteins co-localize on cytoplasmic lipid droplets (c...... JFH1-based recombinants expressing core-NS2 and NS5A from genotypes 1-7, and analysed core and NS5A co-localization in infected cells. Huh7.5 cells were transfected with RNA of core-NS2/NS5A recombinants and putative adaptive mutations were analysed by reverse genetics. Adapted core-NS2/NS5A...... recombinants produced infectivity titres of 10(2.5)-10(4.5) f.f.u. ml(-1). Co-localization analysis demonstrated that the core and NS5A proteins from all genotypes co-localized extensively, and there was no significant difference in protein co-localization among genotypes. In addition, we found that the core...

  9. Kaposi's sarcoma herpesvirus K15 protein contributes to virus-induced angiogenesis by recruiting PLCγ1 and activating NFAT1-dependent RCAN1 expression.

    Science.gov (United States)

    Bala, Kiran; Bosco, Raffaella; Gramolelli, Silvia; Haas, Darya A; Kati, Semra; Pietrek, Marcel; Hävemeier, Anika; Yakushko, Yuri; Singh, Vivek Vikram; Dittrich-Breiholz, Oliver; Kracht, Michael; Schulz, Thomas F

    2012-09-01

    Kaposi's Sarcoma (KS), caused by Kaposi's Sarcoma Herpesvirus (KSHV), is a highly vascularised angiogenic tumor of endothelial cells, characterized by latently KSHV-infected spindle cells and a pronounced inflammatory infiltrate. Several KSHV proteins, including LANA-1 (ORF73), vCyclin (ORF72), vGPCR (ORF74), vIL6 (ORF-K2), vCCL-1 (ORF-K6), vCCL-2 (ORF-K4) and K1 have been shown to exert effects that can lead to the proliferation and atypical differentiation of endothelial cells and/or the secretion of cytokines with angiogenic and inflammatory properties (VEGF, bFGF, IL6, IL8, GROα, and TNFβ). To investigate a role of the KSHV K15 protein in KSHV-mediated angiogenesis, we carried out a genome wide gene expression analysis on primary endothelial cells infected with KSHV wildtype (KSHVwt) and a KSHV K15 deletion mutant (KSHVΔK15). We found RCAN1/DSCR1 (Regulator of Calcineurin 1/Down Syndrome critical region 1), a cellular gene involved in angiogenesis, to be differentially expressed in KSHVwt- vs KSHVΔK15-infected cells. During physiological angiogenesis, expression of RCAN1 in endothelial cells is regulated by VEGF (vascular endothelial growth factor) through a pathway involving the activation of PLCγ1, Calcineurin and NFAT1. We found that K15 directly recruits PLCγ1, and thereby activates Calcineurin/NFAT1-dependent RCAN1 expression which results in the formation of angiogenic tubes. Primary endothelial cells infected with KSHVwt form angiogenic tubes upon activation of the lytic replication cycle. This effect is abrogated when K15 is deleted (KSHVΔK15) or silenced by an siRNA targeting the K15 expression. Our study establishes K15 as one of the KSHV proteins that contribute to KSHV-induced angiogenesis.

  10. Kaposi's sarcoma herpesvirus K15 protein contributes to virus-induced angiogenesis by recruiting PLCγ1 and activating NFAT1-dependent RCAN1 expression.

    Directory of Open Access Journals (Sweden)

    Kiran Bala

    2012-09-01

    Full Text Available Kaposi's Sarcoma (KS, caused by Kaposi's Sarcoma Herpesvirus (KSHV, is a highly vascularised angiogenic tumor of endothelial cells, characterized by latently KSHV-infected spindle cells and a pronounced inflammatory infiltrate. Several KSHV proteins, including LANA-1 (ORF73, vCyclin (ORF72, vGPCR (ORF74, vIL6 (ORF-K2, vCCL-1 (ORF-K6, vCCL-2 (ORF-K4 and K1 have been shown to exert effects that can lead to the proliferation and atypical differentiation of endothelial cells and/or the secretion of cytokines with angiogenic and inflammatory properties (VEGF, bFGF, IL6, IL8, GROα, and TNFβ. To investigate a role of the KSHV K15 protein in KSHV-mediated angiogenesis, we carried out a genome wide gene expression analysis on primary endothelial cells infected with KSHV wildtype (KSHVwt and a KSHV K15 deletion mutant (KSHVΔK15. We found RCAN1/DSCR1 (Regulator of Calcineurin 1/Down Syndrome critical region 1, a cellular gene involved in angiogenesis, to be differentially expressed in KSHVwt- vs KSHVΔK15-infected cells. During physiological angiogenesis, expression of RCAN1 in endothelial cells is regulated by VEGF (vascular endothelial growth factor through a pathway involving the activation of PLCγ1, Calcineurin and NFAT1. We found that K15 directly recruits PLCγ1, and thereby activates Calcineurin/NFAT1-dependent RCAN1 expression which results in the formation of angiogenic tubes. Primary endothelial cells infected with KSHVwt form angiogenic tubes upon activation of the lytic replication cycle. This effect is abrogated when K15 is deleted (KSHVΔK15 or silenced by an siRNA targeting the K15 expression. Our study establishes K15 as one of the KSHV proteins that contribute to KSHV-induced angiogenesis.

  11. The expression of essential components for human influenza virus internalisation in Vero and MDCK cells.

    Science.gov (United States)

    Ugiyadi, Maharani; Tan, Marselina I; Giri-Rachman, Ernawati A; Zuhairi, Fawzi R; Sumarsono, Sony H

    2014-05-01

    MDCK and Vero cell lines have been used as substrates for influenza virus replication. However, Vero cells produced lower influenza virus titer yield compared to MDCK. Influenza virus needs molecules for internalisation of the virus into the host cell, such as influenza virus receptor and clathrin. Human influenza receptor is usually a membrane protein containing Sia(α2,6) Gal, which is added into the protein in the golgi apparatus by α2,6 sialyltransferase (SIAT1). Light clathrin A (LCA), light clathrin B (LCB) and heavy clathrin (HC) are the main components needed for virus endocytosis. Therefore, it is necessary to compare the expression of SIAT1 and clathrin in Vero and MDCK cells. This study is reporting the expression of SIAT1 and clathrin observed in both cells with respect to the levels of (1) RNA by using RT-PCR, (2) protein by using dot blot analysis and confocal microscope. The results showed that Vero and MDCK cells expressed both SIAT1 and clathrin proteins, and the expression of SIAT1 in MDCK was higher compared to Vero cells. On the other hand, the expressions of LCA, LCB and HC protein in MDCK cells were not significantly different to Vero cells. This result showed that the inability of Vero cells to internalize H1N1 influenza virus was possibly due to the lack of transmembrane protein receptor which contained Sia(α2,6) Gal.

  12. Susceptibility of domestic animals to a pseudotype virus bearing RD-114 virus envelope protein.

    Science.gov (United States)

    Miyaho, Rie Nakaoka; Nakagawa, So; Hashimoto-Gotoh, Akira; Nakaya, Yuki; Shimode, Sayumi; Sakaguchi, Shoichi; Yoshikawa, Rokusuke; Takahashi, Mahoko Ueda; Miyazawa, Takayuki

    2015-08-10

    Retroviral vectors are used for gene transduction into cells and have been applied to gene therapy. Retroviral vectors using envelope protein (Env) of RD-114 virus, a feline endogenous retrovirus, have been used for gene transduction. In this study, we investigated the susceptibility to RD-114 Env-pseudotyped virus in twelve domestic animals including cattle, sheep, horse, pig, dog, cat, ferret, mink, rabbit, rat, mouse, and quail. Comparison of nucleotide sequences of ASCT2 (SLC1A5), a receptor of RD-114 virus, in 10 mammalian and 2 avian species revealed that insertion and deletion events at the region C of ASCT2 where RD-114 viral Env interacts occurred independently in the mouse and rat lineage and in the chicken and quail lineage. By the pseudotype virus infection assay, we found that RD-114 Env-pseudotyped virus could efficiently infect all cell lines except those from mouse and rat. Furthermore, we confirmed that bovine ASCT2 (bASCT2) functions as a receptor for RD-114 virus infection. We also investigated bASCT2 mRNA expression in cattle tissues and found that it is expressed in various tissues including lung, spleen and kidney. These results indicate that retrovirus vectors with RD-114 virus Env can be used for gene therapy in large domestic animals in addition to companion animals such as cat and dog. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Regulation of Ebola virus VP40 matrix protein by SUMO

    National Research Council Canada - National Science Library

    Maite Baz-martínez; Ahmed El Motiam; Paula Ruibal; Gabriela N Condezo; Carlos F De La Cruz-herrera; Valerie Lang; Manuel Collado; Carmen San Martín; Manuel S Rodríguez; Cesar Muñoz-fontela; Carmen Rivas

    2016-01-01

    The matrix protein of Ebola virus (EBOV) VP40 regulates viral budding, nucleocapsid recruitment, virus structure and stability, viral genome replication and transcription, and has an intrinsic ability to form virus-like particles...

  14. Expression and immunogenic analysis of recombinant polypeptides derived from capsid protein VP1 for developing subunit vaccine material against hepatitis A virus.

    Science.gov (United States)

    Jang, Kyoung Ok; Park, Jong-Hwa; Lee, Hyun Ho; Chung, Dae Kyun; Kim, Wonyong; Chung, In Sik

    2014-08-01

    Three recombinant polypeptides, VP1-His, VP1-3N-His, and 3D2-His, were produced by Escherichia coli expression system. Recombinant VP1-His, VP1-3N-His, and 3D2-His were expressed as bands with molecular weights of 32, 38, and 30 kDa, respectively. These were purified by affinity chromatography using Ni-NTA Fast-flow resin and/or ion-exchange chromatography using DEAE-Sepharose Fast-flow resin. Intraperitoneal immunizations of recombinant polypeptides successfully elicited the productions of VP1-His, VP1-3N-His, and 3D2-His specific IgG antibodies (IgG subclass distribution of IgG1>IgG2a>IgG2b>IgG3) in sera and induced the secretions of cytokines IFN-γ and IL-6 in spleen cells. Sera from recombinant VP1-His-, VP1-3N-His-, and 3D2-His-immunized mice neutralized the propagation of HAV. The highest neutralizing activity was shown in sera from recombinant VP1-3N-His-immunized mice. These results suggest that recombinant VP1-3N-His can be a useful source for developing hepatitis A virus (HAV) subunit vaccine candidates. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Recombinant low-seroprevalent adenoviral vectors Ad26 and Ad35 expressing the respiratory syncytial virus (RSV) fusion protein induce protective immunity against RSV infection in cotton rats.

    Science.gov (United States)

    Widjojoatmodjo, Myra N; Bogaert, Lies; Meek, Bob; Zahn, Roland; Vellinga, Jort; Custers, Jerome; Serroyen, Jan; Radošević, Katarina; Schuitemaker, Hanneke

    2015-10-05

    RSV is an important cause of lower respiratory tract infections in children, the elderly and in those with underlying medical conditions. Although the high disease burden indicates an urgent need for a vaccine against RSV, no licensed RSV vaccine is currently available. We developed an RSV vaccine candidate based on the low-seroprevalent human adenovirus serotypes 26 and 35 (Ad26 and Ad35) encoding the RSV fusion (F) gene. Single immunization of mice with either one of these vectors induced high titers of RSV neutralizing antibodies and high levels of F specific interferon-gamma-producing T cells. A Th1-type immune response was indicated by a high IgG2a/IgG1 ratio of RSV-specific antibodies, strong induction of RSV-specific interferon-gamma and tumor necrosis factor-alpha cytokine producing CD8 Tcells, and low RSV-specific CD4 T-cell induction. Both humoral and cellular responses were increased upon a boost with RSV-F expressing heterologous adenovirus vector (Ad35 boost after Ad26 prime or vice versa). Both single immunization and prime-boost immunization of cotton rats induced high and long-lasting RSV neutralizing antibody titers and protective immunity against lung and nasal RSV A2 virus load up to at least 30 weeks after immunization. Cotton rats were also completely protected against challenge with a RSV B strain (B15/97) after heterologous prime-boost immunization. Lungs from vaccinated animals showed minimal damage or inflammatory infiltrates post-challenge, in contrast to animals vaccinated with formalin-inactivated virus. Our results suggest that recombinant human adenoviral Ad26 and Ad35 vectors encoding the RSV F gene have the potential to provide broad and durable protection against RSV in humans, and appear safe to be investigated in infants. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. The Zika virus envelope protein glycan loop regulates virion antigenicity.

    Science.gov (United States)

    Goo, Leslie; DeMaso, Christina R; Pelc, Rebecca S; Ledgerwood, Julie E; Graham, Barney S; Kuhn, Richard J; Pierson, Theodore C

    2018-01-02

    Because antibodies are an important component of flavivirus immunity, understanding the antigenic structure of flaviviruses is critical. Compared to dengue virus (DENV), the loop containing the single N-linked glycosylation site on Zika virus (ZIKV) envelope (E) proteins extends further towards the DII fusion loop (DII-FL) on neighboring E proteins within E dimers on mature viruses. Although ZIKV is poorly neutralized by DII-FL antibodies, we demonstrated significantly increased neutralization sensitivity of ZIKV particles incorporating the DENV glycan loop. Increased neutralization sensitivity was independent of E protein glycosylation: ZIKV lacking E protein glycans remained poorly neutralized, whereas ZIKV loop chimeras with or without an E protein glycan were potently neutralized. ZIKV particles lacking the E protein glycan were capable of infecting Raji cells expressing the lectin DC-SIGNR, suggesting the prM glycan of partially mature particles can facilitate entry. Our study provides insight into the determinants of ZIKV E protein function and antigenicity. Copyright © 2017. Published by Elsevier Inc.

  17. Expression of the rice hoja blanca virus (RHBV non-structural protein 3 (NS3 in Escherichia coli and its in situ localization in RHBV-infected rice tissues

    Directory of Open Access Journals (Sweden)

    Miguel Muñoz

    2004-09-01

    Full Text Available The non-structural NS3 protein gene from the rice hoja blanca virus (RHBV was fused to the glutathione- S-transferase carboxilic end and expressed in Escherichia coli strain JM83. Large quantities of fusion protein were produced in insoluble form. The fusion protein was fractionated in SDS-PAGE and purified by electroelution, polyclonal antibodies were raised in rabbit and the antiserum was absorbed with bacterial crude extract. A band of similar size as that of NS3 protein was observed in Western blots using extracts from RHBV-infected rice plants. Immunoelectron microscopy with colloidal gold-labeled antibodies against NS3 protein and the viral nucleocapsid protein revealed in situ accumulation of NS3 protein in the cytoplasm but not in the viral inclusion bodies, vacuoles or chloroplasts of RHBV-infected plants, following the same pattern of distribution as the RHBV nucleocapsid protein. Rev. Biol. Trop. 52(3: 765-775. Epub 2004 Dic 15.El gen que codifica por la proteína no estructural NS3 del virus de la hoja blanca de arroz (RHBV se fusionó al extremo carboxilo del gen de la glutationa-S-transferasa y se expresó en la cepa JM83 de Escherichia coli. Se obtuvieron altas concentraciones de la proteína de fusion (GST-NS3 en forma insoluble. La proteína de fusión se fraccionó en geles de SDS-PAGE, se purificó por electroelución, y se utilizó para producir anticuerpos policlonales en conejo . El antisuero producido se absorbió con extractos crudos de E. coli. Extractos crudos de plantas de arroz sanas e infectadas con el RHBV se evaluaron por Western blots detectándose una banda de peso molecular similar al estimado para la proteína NS3 (23KDa en las plantas infectadas con el virus. Los tejidos provenientes de plantas infectadas con el RHBV se analizaron por medio de microscopia inmunoelectrónica con oro colloidal marcado con anticuerpos contra la proteína NS3 y la nucleoproteína viral N. Se observó una acumulación in situ de la

  18. Immune properties of recombinant vaccinia virus encoding CD154 (CD40L) are determined by expression of virally encoded CD40L and the presence of CD40L protein in viral particles.

    Science.gov (United States)

    Bereta, Michal; Bereta, Joanna; Park, Jonas; Medina, Freddy; Kwak, Heesun; Kaufman, Howard L

    2004-12-01

    Expression of costimulatory molecules by recombinant poxviruses is a promising strategy for enhancing therapeutic vaccines. CD40-CD40L interactions are critical for conditioning dendritic cells (DC) and priming T- and B-cell immunity. We constructed a vaccinia virus expressing murine CD40L (rV-CD40L) and studied its immunomodulatory properties in vitro. Direct DC infection with control vaccinia or psoralen/UV-inactivated rV-CD40L stimulated high levels of interleukin 12 (IL-12) release. However, replication-competent rV-CD40L did not stimulate IL-12 under similar conditions. We observed a high level of CD40L protein on purified viral particles and demonstrated that induction of IL-12 by nonreplicating rV-CD40L was blocked by anti-CD40 antibodies suggesting that functional CD40L on viral particles contributed to alterations in IL-12 synthesis. Since cross-presentation of tumor-associated antigens by DC is augmented by viral infection of tumor cells, we infected MC38 murine colon carcinoma cells with rV-CD40L. Infected cells stimulated IL-12 secretion by DC and proliferation of B cells and DX5(+) (NK/NKT) cells through direct CD40-CD40L interaction. A subpopulation of NKT cells expressing CD40 (NK1.1(+), CD3(lo)) appeared to be a major effector population responding to MC38/rV-CD40L. These results highlight the complex immune regulatory effects of rV-CD40L defined by the cumulative effects of CD40L expression, presence of CD40L protein in viral particles, and the replication potential of the virus.

  19. Proteins of purified Epstein-Barr virus.

    Science.gov (United States)

    Johannsen, Eric; Luftig, Micah; Chase, Michael R; Weicksel, Steve; Cahir-McFarland, Ellen; Illanes, Diego; Sarracino, David; Kieff, Elliott

    2004-11-16

    Mature Epstein-Barr virus (EBV) was purified from the culture medium of infected lymphocytes made functionally conditional for Zta activation of lytic replication by an in-frame fusion with a mutant estrogen receptor. Proteins in purified virus preparations were separated by gradient gel electrophoresis and trypsin-digested; peptides were then analyzed by tandem hydrophobic chromatography, tandem MS sequencing, and MS scans. Potential peptides were matched with EBV and human gene ORFs. Mature EBV was mostly composed of homologues of proteins previously found in a herpes virion. However, EBV homologues to herpes simplex virus capsid-associated or tegument components UL7 (BBRF2), UL14 (BGLF3), and EBV BFRF1 were not significantly detected. Instead, probable tegument components included the EBV and gamma-herpesvirus-encoded BLRF2, BRRF2, BDLF2 and BKRF4 proteins. Actin was also a major tegument protein, and cofilin, tubulin, heat shock protein 90, and heat shock protein 70 were substantial components. EBV envelope glycoprotein gp350 was highly abundant, followed by glycoprotein gH, intact and furin-cleaved gB, gM, gp42, gL, gp78, gp150, and gN. BILF1 (gp64) and proteins associated with latent EBV infection were not detected in virions.

  20. Triggering of the Newcastle Disease Virus Fusion Protein by a Chimeric Attachment Protein That Binds to Nipah Virus Receptors*

    Science.gov (United States)

    Mirza, Anne M.; Aguilar, Hector C.; Zhu, Qiyun; Mahon, Paul J.; Rota, Paul A.; Lee, Benhur; Iorio, Ronald M.

    2011-01-01

    The fusion (F) proteins of Newcastle disease virus (NDV) and Nipah virus (NiV) are both triggered by binding to receptors, mediated in both viruses by a second protein, the attachment protein. However, the hemagglutinin-neuraminidase (HN) attachment protein of NDV recognizes sialic acid receptors, whereas the NiV G attachment protein recognizes ephrinB2/B3 as receptors. Chimeric proteins composed of domains from the two attachment proteins have been evaluated for fusion-promoting activity with each F protein. Chimeras having NiV G-derived globular domains and NDV HN-derived stalks, transmembranes, and cytoplasmic tails are efficiently expressed, bind ephrinB2, and trigger NDV F to promote fusion in Vero cells. Thus, the NDV F protein can be triggered by binding to the NiV receptor, indicating that an aspect of the triggering cascade induced by the binding of HN to sialic acid is conserved in the binding of NiV G to ephrinB2. However, the fusion cascade for triggering NiV F by the G protein and that of triggering NDV F by the chimeras can be distinguished by differential exposure of a receptor-induced conformational epitope. The enhanced exposure of this epitope marks the triggering of NiV F by NiV G but not the triggering of NDV F by the chimeras. Thus, the triggering cascade for NiV G-F fusion may be more complex than that of NDV HN and F. This is consistent with the finding that reciprocal chimeras having NDV HN-derived heads and NiV G-derived stalks, transmembranes, and tails do not trigger either F protein for fusion, despite efficient cell surface expression and receptor binding. PMID:21460213

  1. Triggering of the newcastle disease virus fusion protein by a chimeric attachment protein that binds to Nipah virus receptors.

    Science.gov (United States)

    Mirza, Anne M; Aguilar, Hector C; Zhu, Qiyun; Mahon, Paul J; Rota, Paul A; Lee, Benhur; Iorio, Ronald M

    2011-05-20

    The fusion (F) proteins of Newcastle disease virus (NDV) and Nipah virus (NiV) are both triggered by binding to receptors, mediated in both viruses by a second protein, the attachment protein. However, the hemagglutinin-neuraminidase (HN) attachment protein of NDV recognizes sialic acid receptors, whereas the NiV G attachment protein recognizes ephrinB2/B3 as receptors. Chimeric proteins composed of domains from the two attachment proteins have been evaluated for fusion-promoting activity with each F protein. Chimeras having NiV G-derived globular domains and NDV HN-derived stalks, transmembranes, and cytoplasmic tails are efficiently expressed, bind ephrinB2, and trigger NDV F to promote fusion in Vero cells. Thus, the NDV F protein can be triggered by binding to the NiV receptor, indicating that an aspect of the triggering cascade induced by the binding of HN to sialic acid is conserved in the binding of NiV G to ephrinB2. However, the fusion cascade for triggering NiV F by the G protein and that of triggering NDV F by the chimeras can be distinguished by differential exposure of a receptor-induced conformational epitope. The enhanced exposure of this epitope marks the triggering of NiV F by NiV G but not the triggering of NDV F by the chimeras. Thus, the triggering cascade for NiV G-F fusion may be more complex than that of NDV HN and F. This is consistent with the finding that reciprocal chimeras having NDV HN-derived heads and NiV G-derived stalks, transmembranes, and tails do not trigger either F protein for fusion, despite efficient cell surface expression and receptor binding. © 2011 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. Hepatitis C virus core protein activates autophagy through EIF2AK3 and ATF6 UPR pathway-mediated MAP1LC3B and ATG12 expression

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    Wang, Ji; Kang, Rongyan; Huang, He; Xi, Xueyan; Wang, Bei; Wang, Jianwei; Zhao, Zhendong

    2014-01-01

    HCV infection induces autophagy, but how this occurs is unclear. Here, we report the induction of autophagy by the structural HCV core protein and subsequent endoplasmic reticular (ER) stress in Huh7 hepatoma cells. During ER stress, both the EIF2AK3 and ATF6 pathways of the unfolded protein response (UPR) were activated by HCV core protein. Then, these pathways upregulated transcription factors ATF4 and DDIT3. The ERN1-XBP1 pathway was not activated. Through ATF4 in the EIF2AK3 pathway, the autophagy gene ATG12 was upregulated. DDIT3 upregulated the transcription of autophagy gene MAP1LC3B (LC3B) by directly binding to the –253 to –99 base region of the LC3B promoter, contributing to the development of autophagy. Collectively, these data suggest not only a novel role for the HCV core protein in autophagy but also offer new insight into detailed molecular mechanisms with respect to HCV-induced autophagy, specifically how downstream UPR molecules regulate key autophagic gene expression. PMID:24589849

  3. Systematic analysis of protein identity between Zika virus and other arthropod-borne viruses.

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    Chang, Hsiao-Han; Huber, Roland G; Bond, Peter J; Grad, Yonatan H; Camerini, David; Maurer-Stroh, Sebastian; Lipsitch, Marc

    2017-07-01

    To analyse the proportions of protein identity between Zika virus and dengue, Japanese encephalitis, yellow fever, West Nile and chikungunya viruses as well as polymorphism between different Zika virus strains. We used published protein sequences for the Zika virus and obtained protein sequences for the other viruses from the National Center for Biotechnology Information (NCBI) protein database or the NCBI virus variation resource. We used BLASTP to find regions of identity between viruses. We quantified the identity between the Zika virus and each of the other viruses, as well as within-Zika virus polymorphism for all amino acid k-mers across the proteome, with k ranging from 6 to 100. We assessed accessibility of protein fragments by calculating the solvent accessible surface area for the envelope and nonstructural-1 (NS1) proteins. In total, we identified 294 Zika virus protein fragments with both low proportion of identity with other viruses and low levels of polymorphisms among Zika virus strains. The list includes protein fragments from all Zika virus proteins, except NS3. NS4A has the highest number (190 k-mers) of protein fragments on the list. We provide a candidate list of protein fragments that could be used when developing a sensitive and specific serological test to detect previous Zika virus infections.

  4. A novel recombinant pseudorabies virus expressing parvovirus VP2 gene: Immunogenicity and protective efficacy in swine.

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    Chen, Yang; Guo, Wanzhu; Xu, Zhiwen; Yan, Qigui; Luo, Yan; Shi, Qian; Chen, Dishi; Zhu, Ling; Wang, Xiaoyu

    2011-06-16

    Porcine parvovirus (PPV) VP2 gene has been successfully expressed in many expression systems resulting in self-assembly of virus-like particles (VLPs) with similar morphology to the native capsid. Here, a pseudorabies virus (PRV) system was adopted to express the PPV VP2 gene. A recombinant PRV SA215/VP2 was obtained by homologous recombination between the vector PRV viral DNA and a transfer plasmid. Then recombinant virus was purified with plaque purification, and its identity confirmed by PCR amplification, Western blot and indirect immunofluorescence (IFA) analyses. Electronic microscopy of PRV SA215/VP2 confirmed self-assembly of both pseudorabies virus and VLPs from VP2 protein. Immunization of piglets with recombinant virus elicited PRV-specific and PPV-specific humoral immune responses and provided complete protection against a lethal dose of PRV challenges. Gilts immunized with recombinant viruses induced PPV-specific antibodies, and significantly reduced the mortality rate of (1 of 28) following virulent PPV challenge compared with the control (7 of 31). Furthermore, PPV virus DNA was not detected in the fetuses of recombinant virus immunized gilts. In this study, a recombinant PRV SA215/VP2 virus expressing PPV VP2 protein was constructed using PRV SA215 vector. The safety, immunogenicity, and protective efficacy of the recombinant virus were demonstrated in piglets and primiparous gilts. This recombinant PRV SA215/VP2 represents a suitable candidate for the development of a bivalent vaccine against both PRV and PPV infection.

  5. Localization and dynamic expression of a 27.8 kDa receptor protein for lymphocystis disease virus infection in sea bass ( Lateolabrax japonicus) tissues

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    Wu, Ronghua; Sheng, Xiuzhen; Tang, Xiaoqian; Xing, Jing; Zhan, Wenbin

    2017-10-01

    Lymphocystis disease virus (LCDV) infects target cells by attaching to a 27.8 kDa receptor (27.8R) protein in flounder Paralichthys olivaceus, and anti-27.8R monoclonal antibodies (MAbs) have been developed. However, the 27.8R existence in tissues of sea bass ( Lateolabrax japonicus) and its role in LCDV infection have remained unclear. In this study, the results of western blotting demonstrated that the same 27.8R was shared by flounder and sea bass. LCDV-free sea bass individuals were intramuscularly injected with LCDV, and viral copies were detected in tissues from 3 h post infection and showed a time-dependent increase during 9 days infection. Distribution and synthesis of 27.8R in sea bass tissues were investigated by using anti-27.8R MAbs as probes. It was found that 27.8R was distributed in all the tested tissues. The levels of 27.8R protein were highest in gill and skin, then a bit lowly in stomach, head kidney and heart, followed by spleen, intestine, blood cells, gonad and liver, and least in kidney and brain in healthy sea bass. Upon LCDV infection, 27.8R synthesis was up-regulated in each tissue, and higher in the tissues with higher LCDV copies. The 27.8R and LCDV were detected in some peripheral blood leukocytes but not in red blood cells. These results suggested that 27.8R was widely distributed in sea bass tissues, and it served as a receptor and correlated with tissue tropism of LCDV infection. Furthermore, leukocytes had the potential of being a LCDV carrier and were responsible for a systemic infection of LCDV in sea bass.

  6. Epstein-Barr virus infection induces indoleamine 2,3-dioxygenase expression in human monocyte-derived macrophages through p38/mitogen-activated protein kinase and NF-κB pathways: impairment in T cell functions.

    Science.gov (United States)

    Liu, Wan-li; Lin, Yue-hao; Xiao, Han; Xing, Shan; Chen, Hao; Chi, Pei-dong; Zhang, Ge

    2014-06-01

    Epstein-Barr virus (EBV) infection has been observed in tumor-infiltrated macrophages, but its infection effects on macrophage immune functions are poorly understood. Here, we showed that some macrophages in the tumor stroma of nasopharyngeal carcinoma (NPC) tissue expressed the immunosuppressive protein indoleamine 2,3-dioxygenase (IDO) more strongly than did tumor cells. EBV infection induced mRNA, protein, and enzymatic activity of IDO in human monocyte-derived macrophages (MDMs). Infection increased the production of tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6), whereas the neutralizing antibodies against TNF-α and IL-6 inhibited IDO induction. EBV infection also activated the mitogen-activated protein kinase (MAPK) p38 and NF-κB, and the inhibition of these two pathways with SB202190 and SN50 almost abrogated TNF-α and IL-6 production and inhibited IDO production. Moreover, the activation of IDO in response to EBV infection of MDMs suppressed the proliferation of T cells and impaired the cytotoxic activity of CD8(+) T cells, whereas the inhibition of IDO activity with 1-methyl-l-tryptophan (1-MT) did not affect T cell proliferation and function. These findings indicate that EBV-induced IDO expression in MDMs is substantially mediated by IL-6- and TNF-α-dependent mechanisms via the p38/MAPK and NF-κB pathways, suggesting that a possible role of EBV-mediated IDO expression in tumor stroma of NPC may be to create a microenvironment of suppressed T cell immune responses. CD8(+) cytotoxic T lymphocytes (CTLs) play an important role in the control of viral infections and destroy tumor cells. Activation of the tryptophan-catabolizing enzyme indoleamine 2,3-dioxygenase (IDO) in cancer tissues facilitates immune escape by the impairment of CTL functions. IDO expression was observed in some macrophages of the tumor stroma of nasopharyngeal carcinoma (NPC) tissue, and IDO could be induced in Epstein-Barr virus (EBV)-infected human monocyte

  7. Involvement of C4 protein of beet severe curly top virus (family Geminiviridae in virus movement.

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    Kunling Teng

    Full Text Available BACKGROUND: Beet severe curly top virus (BSCTV is a leafhopper transmitted geminivirus with a monopartite genome. C4 proteins encoded by geminivirus play an important role in virus/plant interaction. METHODS AND FINDINGS: To understand the function of C4 encoded by BSCTV, two BSCTV mutants were constructed by introducing termination codons in ORF C4 without affecting the amino acids encoded by overlapping ORF Rep. BSCTV mutants containing disrupted ORF C4 retained the ability to replicate in Arabidopsis protoplasts and in the agro-inoculated leaf discs of N. benthamiana, suggesting C4 is not required for virus DNA replication. However, both mutants did not accumulate viral DNA in newly emerged leaves of inoculated N. benthamiana and Arabidopsis, and the inoculated plants were asymptomatic. We also showed that C4 expression in plant could help C4 deficient BSCTV mutants to move systemically. C4 was localized in the cytosol and the nucleus in both Arabidopsis protoplasts and N. benthamiana leaves and the protein appeared to bind viral DNA and ds/ssDNA nonspecifically, displaying novel DNA binding properties. CONCLUSIONS: Our results suggest that C4 protein in BSCTV is involved in symptom production and may facilitate virus movement instead of virus replication.

  8. Modulation of apoptosis by V protein mumps virus

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    Herrera-Camacho Irma

    2011-05-01

    Full Text Available Abstract Background The Urabe AM9 vaccine strain of mumps virus contains two variants of V protein: VWT (of HN-A1081 viral population and VGly (of HN-G1081. The V protein is a promoting factor of viral replication by blocking the IFN antiviral pathway. Findings We studied the relationship between V protein variants and IFN-α2b-induced apoptosis. V proteins decrease activation of the extrinsic IFN-α2b-induced apoptotic pathway monitored by the caspase 8 activity, being the effect greater with the VWT protein. Both V proteins decrease the activity of caspase 9 of the intrinsic apoptotic pathway. In a system without IFN, the VWT and VGly proteins expression promotes activation of caspases 3 and 7. However, when the cellular system was stimulated with IFN-α, this activity decreased partially. TUNEL assay shows that for treatment with IFN-α and ibuprofen of cervical adenocarcinoma cells there is nuclear DNA fragmentation but the V protein expression reduces this process. Conclusions The reduction in the levels of caspases and DNA fragmentation, suggesting that V protein, particularly VWT protein of Urabe AM9 vaccine strain, modulates apoptosis. In addition, the VWT protein shows a protective role for cell proliferation in the presence of antiproliferative signals.

  9. Expression of human papilloma virus type 16 E5 protein in amelanotic melanoma cells regulates endo-cellular pH and restores tyrosinase activity

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    Coccia Raffaella

    2009-01-01

    Full Text Available Abstract Background Melanin synthesis, the elective trait of melanocytes, is regulated by tyrosinase activity. In tyrosinase-positive amelanotic melanomas this rate limiting enzyme is inactive because of acidic endo-melanosomal pH. The E5 oncogene of the Human Papillomavirus Type 16 is a small transmembrane protein with a weak transforming activity and a role during the early steps of viral infections. E5 has been shown to interact with 16 kDa subunit C of the trans-membrane Vacuolar ATPase proton pump ultimately resulting in its functional suppressions. However, the cellular effects of such an interaction are still under debate. With this work we intended to explore whether the HPV16 E5 oncoprotein does indeed interact with the vacuolar ATPase proton pump once expressed in intact human cells and whether this interaction has functional consequences on cell metabolism and phenotype. Methods The expression of the HPV16-E5 oncoproteins was induced in two Tyrosinase-positive amelanotic melanomas (the cell lines FRM and M14 by a retroviral expression construct. Modulation of the intracellular pH was measured with Acridine orange and fluorescence microscopy. Expression of tyrosinase and its activity was followed by RT-PCR, Western Blot and enzyme assay. The anchorage-independence growth and the metabolic activity of E5 expressing cells were also monitored. Results We provide evidence that in the E5 expressing cells interaction between E5 and V-ATPase determines an increase of endo-cellular pH. The cellular alkalinisation in turn leads to the post-translational activation of tyrosinase, melanin synthesis and phenotype modulation. These effects are associated with an increased activation of tyrosine analogue anti-blastic drugs. Conclusion Once expressed within intact human cells the HPV16-E5 oncoprotein does actually interact with the vacuolar V-ATPase proton pump and this interaction induces a number of functional effects. In amelanotic melanomas these

  10. Integrated process for the purification and immobilization of the envelope protein domain III of dengue virus type 2 expressed in Rachiplusia nu larvae and its potential application in a diagnostic assay.

    Science.gov (United States)

    Smith, María Emilia; Targovnik, Alexandra Marisa; Cerezo, Julieta; Morales, María Alejandra; Miranda, María Victoria; Talou, Julián Rodríguez

    2017-03-01

    Dengue incidence has grown dramatically in the last years, with about 40% of the world population at risk of infection. Recently, a vaccine developed by Sanofi Pasteur has been registered, but only in a few countries. Moreover, specific antiviral drugs are not available. Thus, an efficient and accurate diagnosis is important for disease management. To develop a low-cost immunoassay for dengue diagnosis, in the present study we expressed the envelope protein domain III of dengue virus type 2 in Rachiplusia nu larvae by infection with a recombinant baculovirus. The antigen was expressed as a fusion to hydrophobin I (DomIIIHFBI) to easily purify it by an aqueous two-phase system (ATPS) and to efficiently immobilize it in immunoassay plates. A high level of recombinant DomIIIHFBI was obtained in R. nu, where yields reached 4.5 mg per g of larva. Also, we were able to purify DomIIIHFBI by an ATPS with 2% of Triton X-114, reaching a yield of 73% and purity higher than 80% in a single purification step. The recombinant DomIIIHFBI was efficiently immobilized in hydrophobic surface plates. The immunoassay we developed with the immobilized antigen was able to detect IgG specific for dengue virus type 2 in serum samples and not for other serotypes. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Herpes simplex virus induces the marked up-regulation of the zinc finger transcriptional factor INSM1, which modulates the expression and localization of the immediate early protein ICP0

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    Kimura Hiroshi

    2011-05-01

    Full Text Available Abstract Background Herpes simplex viruses (HSVs rapidly shut off macromolecular synthesis in host cells. In contrast, global microarray analyses have shown that HSV infection markedly up-regulates a number of host cell genes that may play important roles in HSV-host cell interactions. To understand the regulatory mechanisms involved, we initiated studies focusing on the zinc finger transcription factor insulinoma-associated 1 (INSM1, a host cell protein markedly up-regulated by HSV infection. Results INSM1 gene expression in HSV-1-infected normal human epidermal keratinocytes increased at least 400-fold 9 h after infection; INSM1 promoter activity was also markedly stimulated. Expression and subcellular localization of the immediate early HSV protein ICP0 was affected by INSM1 expression, and chromatin immunoprecipitation (ChIP assays revealed binding of INSM1 to the ICP0 promoter. Moreover, the role of INSM1 in HSV-1 infection was further clarified by inhibition of HSV-1 replication by INSM1-specific siRNA. Conclusions The results suggest that INSM1 up-regulation plays a positive role in HSV-1 replication, probably by binding to the ICP0 promoter.

  12. Prediction of virus-host protein-protein interactions mediated by short linear motifs.

    Science.gov (United States)

    Becerra, Andrés; Bucheli, Victor A; Moreno, Pedro A

    2017-03-09

    Short linear motifs in host organisms proteins can be mimicked by viruses to create protein-protein interactions that disable or control metabolic pathways. Given that viral linear motif instances of host motif regular expressions can be found by chance, it is necessary to develop filtering methods of functional linear motifs. We conduct a systematic comparison of linear motifs filtering methods to develop a computational approach for predicting motif-mediated protein-protein interactions between human and the human immunodeficiency virus 1 (HIV-1). We implemented three filtering methods to obtain linear motif sets: 1) conserved in viral proteins (C), 2) located in disordered regions (D) and 3) rare or scarce in a set of randomized viral sequences (R). The sets C,D,R are united and intersected. The resulting sets are compared by the number of protein-protein interactions correctly inferred with them - with experimental validation. The comparison is done with HIV-1 sequences and interactions from the National Institute of Allergy and Infectious Diseases (NIAID). The number of correctly inferred interactions allows to rank the interactions by the sets used to deduce them: D∪R and C. The ordering of the sets is descending on the probability of capturing functional interactions. With respect to HIV-1, the sets C∪R, D∪R, C∪D∪R infer all known interactions between HIV1 and human proteins mediated by linear motifs. We found that the majority of conserved linear motifs in the virus are located in disordered regions. We have developed a method for predicting protein-protein interactions mediated by linear motifs between HIV-1 and human proteins. The method only use protein sequences as inputs. We can extend the software developed to any other eukaryotic virus and host in order to find and rank candidate interactions. In future works we will use it to explore possible viral attack mechanisms based on linear motif mimicry.

  13. Expressed protein ligation for a large dimeric protein

    NARCIS (Netherlands)

    Karagöz, G.E.; Sinnige, T; Hsieh, O.; Rüdiger, S.G.D.

    2011-01-01

    Expressed protein ligation (EPL) is a protein engineering tool for post-translational ligation of protein or peptide fragments. This technique allows modification of specific parts of proteins, opening possibilities for incorporating probes for biophysical applications such as nuclear magnetic

  14. Production of FMDV virus-like particles by a SUMO fusion protein approach in Escherichia coli

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    Liang Shu-Mei

    2009-08-01

    Full Text Available Abstract Virus-like particles (VLPs are formed by the self-assembly of envelope and/or capsid proteins from many viruses. Some VLPs have been proven successful as vaccines, and others have recently found applications as carriers for foreign antigens or as scaffolds in nanoparticle biotechnology. However, production of VLP was usually impeded due to low water-solubility of recombinant virus capsid proteins. Previous studies revealed that virus capsid and envelope proteins were often posttranslationally modified by SUMO in vivo, leading into a hypothesis that SUMO modification might be a common mechanism for virus proteins to retain water-solubility or prevent improper self-aggregation before virus assembly. We then propose a simple approach to produce VLPs of viruses, e.g., foot-and-mouth disease virus (FMDV. An improved SUMO fusion protein system we developed recently was applied to the simultaneous expression of three capsid proteins of FMDV in E. coli. The three SUMO fusion proteins formed a stable heterotrimeric complex. Proteolytic removal of SUMO moieties from the ternary complexes resulted in VLPs with size and shape resembling the authentic FMDV. The method described here can also apply to produce capsid/envelope protein complexes or VLPs of other disease-causing viruses.

  15. Complementing defective viruses that express separate paramyxovirus glycoproteins provide a new vaccine vector approach.

    Science.gov (United States)

    Chattopadhyay, Anasuya; Rose, John K

    2011-03-01

    Replication-defective vaccine vectors based on vesicular stomatitis virus (VSV) lacking its envelope glycoprotein gene (G) are highly effective in animal models. However, such ΔG vectors are difficult to grow because they require complementation with the VSV G protein. In addition, the complementing G protein induces neutralizing antibodies in animals and thus limits multiple vector applications. In the process of generating an experimental Nipah virus (a paramyxovirus) vaccine, we generated two defective VSVΔG vectors, each expressing one of the two Nipah virus (NiV) glycoproteins (G and F) that are both required for virus entry to host cells. These replication-defective VSV vectors were effective at generating NiV neutralizing antibody in mice. Most interestingly, we found that these two defective viruses could be grown together and passaged in tissue culture cells in the absence of VSV G complementation. This mixture of complementing defective viruses was also highly effective at generating NiV neutralizing antibody in animals. This novel approach to growing and producing a vaccine from two defective viruses could be generally applicable to vaccine production for other paramyxoviruses or for other viruses where the expression of at least two different proteins is required for viral entry. Such an approach minimizes biosafety concerns that could apply to single, replication-competent VSV recombinants expressing all proteins required for infection.

  16. Citrus tristeza virus p23: a unique protein mediating key virus-host interactions.

    Science.gov (United States)

    Flores, Ricardo; Ruiz-Ruiz, Susana; Soler, Nuria; Sánchez-Navarro, Jesús; Fagoaga, Carmen; López, Carmelo; Navarro, Luis; Moreno, Pedro; Peña, Leandro

    2013-01-01

    The large RNA genome of Citrus tristeza virus (CTV; ca. 20 kb) contains 12 open reading frames, with the 3'-terminal one corresponding to a protein of 209 amino acids (p23) that is expressed from an abundant subgenomic RNA. p23, an RNA-binding protein with a putative zinc-finger domain and some basic motifs, is unique to CTV because no homologs have been found in other closteroviruses, including the type species of the genus Beet yellows virus (despite both viruses having many homologous genes). Consequently, p23 might have evolved for the specific interaction of CTV with its citrus hosts. From a functional perspective p23 has been involved in many roles: (i) regulation of the asymmetrical accumulation of CTV RNA strands, (ii) induction of the seedling yellows syndrome in sour orange and grapefruit, (iii) intracellular suppression of RNA silencing, (iv) elicitation of CTV-like symptoms when expressed ectopically as a transgene in several Citrus spp., and (v) enhancement of systemic infection (and virus accumulation) in sour orange and CTV release from the phloem in p23-expressing transgenic sweet and sour orange. Moreover, transformation of Mexican lime with intron-hairpin constructs designed for the co-inactivation of p23 and the two other CTV silencing suppressors results in complete resistance against the homologous virus. From a cellular point of view, recent data indicate that p23 accumulates preferentially in the nucleolus, being the first closterovirus protein with such a subcellular localization, as well as in plasmodesmata. These major accumulation sites most likely determine some of the functional roles of p23.

  17. Oligomerization of Uukuniemi virus nucleocapsid protein

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    Katz Anna

    2010-08-01

    Full Text Available Abstract Background Uukuniemi virus (UUKV belongs to the Phlebovirus genus in the family Bunyaviridae. As a non-pathogenic virus for humans UUKV has served as a safe model bunyavirus in a number of studies addressing fundamental questions such as organization and regulation of viral genes, genome replication, structure and assembly. The present study is focused on the oligomerization of the UUKV nucleocapsid (N protein, which plays an important role in several steps of virus replication. The aim was to locate the domains involved in the N protein oligomerization and study the process in detail. Results A set of experiments concentrating on the N- and C-termini of the protein was performed, first by completely or partially deleting putative N-N-interaction domains and then by introducing point mutations of amino acid residues. Mutagenesis strategy was based on the computer modeling of secondary and tertiary structure of the N protein. The N protein mutants were studied in chemical cross-linking, immunofluorescence, mammalian two-hybrid, minigenome, and virus-like particle-forming assays. The data showed that the oligomerization ability of UUKV-N protein depends on the presence of intact α-helices on both termini of the N protein molecule and that a specific structure in the N-terminal region plays a crucial role in the N-N interaction(s. This structure is formed by two α-helices, rich in amino acid residues with aromatic (W7, F10, W19, F27, F31 or long aliphatic (I14, I24 side chains. Furthermore, some of the N-terminal mutations (e.g. I14A, I24A, F31A affected the N protein functionality both in mammalian two-hybrid and minigenome assays. Conclusions UUKV-N protein has ability to form oligomers in chemical cross-linking and mammalian two-hybrid assays. In mutational analysis, some of the introduced single-point mutations abolished the N protein functionality both in mammalian two-hybrid and minigenome assays, suggesting that especially the N

  18. Nuclear proteins hijacked by mammalian cytoplasmic plus strand RNA viruses

    Energy Technology Data Exchange (ETDEWEB)

    Lloyd, Richard E., E-mail: rlloyd@bcm.edu

    2015-05-15

    Plus strand RNA viruses that replicate in the cytoplasm face challenges in supporting the numerous biosynthetic functions required for replication and propagation. Most of these viruses are genetically simple and rely heavily on co-opting cellular proteins, particularly cellular RNA-binding proteins, into new roles for support of virus infection at the level of virus-specific translation, and building RNA replication complexes. In the course of infectious cycles many nuclear-cytoplasmic shuttling proteins of mostly nuclear distribution are detained in the cytoplasm by viruses and re-purposed for their own gain. Many mammalian viruses hijack a common group of the same factors. This review summarizes recent gains in our knowledge of how cytoplasmic RNA viruses use these co-opted host nuclear factors in new functional roles supporting virus translation and virus RNA replication and common themes employed between different virus groups. - Highlights: • Nuclear shuttling host proteins are commonly hijacked by RNA viruses to support replication. • A limited group of ubiquitous RNA binding proteins are commonly hijacked by a broad range of viruses. • Key virus proteins alter roles of RNA binding proteins in different stages of virus replication.

  19. Expression and characterization of highly antigenic domains of chicken anemia virus viral VP2 and VP3 subunit proteins in a recombinant E. coli for sero-diagnostic applications.

    Science.gov (United States)

    Lai, Guan-Hua; Lin, Ming-Kuem; Lien, Yi-Yang; Fu, Jiun-Hau; Chen, Hsi-Jien; Huang, Chi-Hung; Tzen, Jason T C; Lee, Meng-Shiou

    2013-08-13

    Chicken anemia virus (CAV) is an important viral pathogen that causes anemia and severe immunodeficiency syndrome in chickens worldwide. Generally, CAV infection occurs via vertical transmission in young chicks that are less than two weeks old, which are very susceptible to the disease. Therefore, epidemiological investigations of CAV infection and/or the evaluation of the immunization status of chickens is necessary for disease control. Up to the present, systematically assessing viral protein antigenicity and/or determining the immunorelevant domain(s) of viral proteins during serological testing for CAV infection has never been performed. The expression, production and antigenic characterization of CAV viral proteins such as VP1, VP2 and VP3, and their use in the development of diagnostic kit would be useful for CAV infection prevention. Three CAV viral proteins VP1, VP2 and VP3 was separately cloned and expressed in recombinant E. coli. The purified recombinant CAV VP1, VP2 and VP3 proteins were then used as antigens in order to evaluate their reactivity against chicken sera using indirect ELISA. The results indicated that VP2 and VP3 show good immunoreactivity with CAV-positive chicken sera, whereas VP1 was found to show less immunoreactivity than VP2 and VP3. To carry out the further antigenic characterization of the immunorelevant domains of the VP2 and VP3 proteins, five recombinant VP2 subunit proteins (VP2-435N, VP2-396N, VP2-345N, VP2-171C and VP2-318C) and three recombinant VP3 subunit proteins (VP3-123N, VP3-246M, VP3-366C), spanning the defined regions of VP2 and VP3 were separately produced by an E. coli expression system. These peptides were then used as antigens in indirect ELISAs against chicken sera. The results of these ELISAs using truncated recombinant VP2 and VP3 subunit proteins as coating antigen showed that VP2-345N, VP2-396N and VP3-246M gave good immunoreactivity with CAV-positive chicken sera compared to the other subunit proteins

  20. Tobacco mosaic virus-directed reprogramming of auxin/indole acetic acid protein transcriptional responses enhances virus phloem loading.

    Science.gov (United States)

    Collum, Tamara D; Padmanabhan, Meenu S; Hsieh, Yi-Cheng; Culver, James N

    2016-05-10

    Vascular phloem loading has long been recognized as an essential step in the establishment of a systemic virus infection. In this study, an interaction between the replication protein of tobacco mosaic virus (TMV) and phloem-specific auxin/indole acetic acid (Aux/IAA) transcriptional regulators was found to modulate virus phloem loading in an age-dependent manner. Promoter expression studies show that in mature tissues TMV 126/183-kDa-interacting Aux/IAAs predominantly express and accumulate within the nuclei of phloem companion cells (CCs). Furthermore, CC Aux/IAA nuclear localization is disrupted upon infection with an interacting virus. In situ analysis of virus spread shows that the inability to disrupt Aux/IAA CC nuclear localization correlates with a reduced ability to load into the vascular tissue. Subsequent systemic movement assays also demonstrate that a virus capable of disrupting Aux/IAA localization is significantly more competitive at moving out of older plant tissues than a noninteracting virus. Similarly, CC expression and overaccumulation of a degradation-resistant Aux/IAA-interacting protein was found to inhibit TMV accumulation and phloem loading selectively in flowering plants. Transcriptional expression studies demonstrate a role for Aux/IAA-interacting proteins in the regulation of salicylic and jasmonic acid host defense responses as well as virus-specific movement factors, including pectin methylesterase, that are involved in regulating plasmodesmata size-exclusion limits and promoting virus cell-to-cell movement. Combined, these findings indicate that TMV directs the reprogramming of auxin-regulated gene expression within the vascular phloem of mature tissues as a means to enhance phloem loading and systemic spread.

  1. Generation of Recombinant Modified Vaccinia Virus Ankara Encoding VP2, NS1, and VP7 Proteins of Bluetongue Virus.

    Science.gov (United States)

    Marín-López, Alejandro; Ortego, Javier

    2016-01-01

    Modified Vaccinia Virus Ankara (MVA) is employed widely as an experimental vaccine vector for its lack of replication in mammalian cells and high expression level of foreign/heterologous genes. Recombinant MVAs (rMVAs) are used as platforms for protein production as well as vectors to generate vaccines against a high number of infectious diseases and other pathologies. The portrait of the virus combines desirable elements such as high-level biological safety, the ability to activate appropriate innate immune mediators upon vaccination, and the capacity to deliver substantial amounts of heterologous antigens. Recombinant MVAs encoding proteins of bluetongue virus (BTV), an Orbivirus that infects domestic and wild ruminants transmitted by biting midges of the Culicoides species, are excellent vaccine candidates against this virus. In this chapter we describe the methods for the generation of rMVAs encoding VP2, NS1, and VP7 proteins of bluetongue virus as a model example for orbiviruses. The protocols included cover the cloning of VP2, NS1, and VP7 BTV-4 genes in a transfer plasmid, the construction of recombinant MVAs, the titration of virus working stocks and the protein expression analysis by immunofluorescence and radiolabeling of rMVA infected cells as well as virus purification.

  2. Expression, purification and crystallization of a lyssavirus matrix (M) protein

    Energy Technology Data Exchange (ETDEWEB)

    Assenberg, René [Division of Structural Biology and Oxford Protein Production Facility, The Henry Wellcome Building for Genomic Medicine, Oxford University, Roosevelt Drive, Oxford OX3 7BN (United Kingdom); Delmas, Olivier [UPRE Lyssavirus Dynamics and Host Adaptation, WHO Collaborating Centre for Reference and Research on Rabies, Institut Pasteur, 28 Rue du Docteur Roux, 75724 Paris CEDEX 15 (France); Graham, Stephen C.; Verma, Anil; Berrow, Nick; Stuart, David I.; Owens, Raymond J. [Division of Structural Biology and Oxford Protein Production Facility, The Henry Wellcome Building for Genomic Medicine, Oxford University, Roosevelt Drive, Oxford OX3 7BN (United Kingdom); Bourhy, Hervé [UPRE Lyssavirus Dynamics and Host Adaptation, WHO Collaborating Centre for Reference and Research on Rabies, Institut Pasteur, 28 Rue du Docteur Roux, 75724 Paris CEDEX 15 (France); Grimes, Jonathan M., E-mail: jonathan@strubi.ox.ac.uk [Division of Structural Biology and Oxford Protein Production Facility, The Henry Wellcome Building for Genomic Medicine, Oxford University, Roosevelt Drive, Oxford OX3 7BN (United Kingdom)

    2008-04-01

    The expression, purification and crystallization of the full-length matrix protein from three lyssaviruses is described. The matrix (M) proteins of lyssaviruses (family Rhabdoviridae) are crucial to viral morphogenesis as well as in modulating replication and transcription of the viral genome. To date, no high-resolution structural information has been obtained for full-length rhabdovirus M. Here, the cloning, expression and purification of the matrix proteins from three lyssaviruses, Lagos bat virus (LAG), Mokola virus and Thailand dog virus, are described. Crystals have been obtained for the full-length M protein from Lagos bat virus (LAG M). Successful crystallization depended on a number of factors, in particular the addition of an N-terminal SUMO fusion tag to increase protein solubility. Diffraction data have been recorded from crystals of native and selenomethionine-labelled LAG M to 2.75 and 3.0 Å resolution, respectively. Preliminary analysis indicates that these crystals belong to space group P6{sub 1}22 or P6{sub 5}22, with unit-cell parameters a = b = 56.9–57.2, c = 187.9–188.6 Å, consistent with the presence of one molecule per asymmetric unit, and structure determination is currently in progress.

  3. Novel vector vaccine against Brucella abortus based on influenza A viruses expressing Brucella L7/L12 or Omp16 proteins: evaluation of protection in pregnant heifers.

    Science.gov (United States)

    Tabynov, Kaissar; Yespembetov, Bolat; Sansyzbay, Abylai

    2014-10-14

    The present study provides the first information about the protection of a novel influenza viral vector vaccine expressing the Brucella proteins ribosomal L7/L12 or Omp16 containing the adjuvant Montanide Gel01 in pregnant heifers. Immunization of pregnant heifers was conducted via the conjunctival (n=10) or subcutaneous (n=10) route using cross prime and booster vaccination schedules at an interval of 28 days. The vector vaccine was evaluated in comparison with positive control groups vaccinated with Brucella abortus S19 (n=10) or B. abortus RB51 (n=10) and a negative (PBS+Montanide Gel01; n=10) control group. Via both the conjunctival or subcutaneous route, evaluation of protectiveness against abortion, effectiveness of vaccination and index of infection (in heifers and their fetuses or calves) demonstrated the vector vaccine provided good protection against B. abortus 544 infection compared to the negative control group (PBS+Montanide Gel01) and comparable protection to commercial vaccines B. abortus S19 or B. abortus RB51. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Induction of protective immunity in swine by recombinant bamboo mosaic virus expressing foot-and-mouth disease virus epitopes

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    Lin Na-Sheng

    2007-09-01

    Full Text Available Abstract Background Plant viruses can be employed as versatile vectors for the production of vaccines by expressing immunogenic epitopes on the surface of chimeric viral particles. Although several viruses, including tobacco mosaic virus, potato virus X and cowpea mosaic virus, have been developed as vectors, we aimed to develop a new viral vaccine delivery system, a bamboo mosaic virus (BaMV, that would carry larger transgene loads, and generate better immunity in the target animals with fewer adverse environmental effects. Methods We engineered the BaMV as a vaccine vector expressing the antigenic epitope(s of the capsid protein VP1 of foot-and-mouth disease virus (FMDV. The recombinant BaMV plasmid (pBVP1 was constructed by replacing DNA encoding the 35 N-terminal amino acid residues of the BaMV coat protein with that encoding 37 amino acid residues (T128-N164 of FMDV VP1. Results The pBVP1 was able to infect host plants and to generate a chimeric virion BVP1 expressing VP1 epitopes in its coat protein. Inoculation of swine with BVP1 virions resulted in the production of anti-FMDV neutralizing antibodies. Real-time PCR analysis of peripheral blood mononuclear cells from the BVP1-immunized swine revealed that they produced VP1-specific IFN-γ. Furthermore, all BVP1-immunized swine were protected against FMDV challenge. Conclusion Chimeric BaMV virions that express partial sequence of FMDV VP1 can effectively induce not only humoral and cell-mediated immune responses but also full protection against FMDV in target animals. This BaMV-based vector technology may be applied to other vaccines that require correct expression of antigens on chimeric viral particles.

  5. Construction of PVX virus-expression vector to express enterotoxin ...

    African Journals Online (AJOL)

    Potato X potyvirus (PVX)-based vector has been comprehensively applied in transient expression system. In order to produce the heterologous proteins more quickly and stably, the ClaI and NotI enzyme sites were introduced into the Enterotoxin fusion gene LTB-ST by polymerase chain reaction (PCR) and the LTB-ST ...

  6. Citrus tristeza virus p23: a unique protein mediating key virus-host interactions

    Directory of Open Access Journals (Sweden)

    Ricardo eFlores

    2013-05-01

    Full Text Available The large RNA genome of CTV (ca. 20 kb contains 12 open reading frames (ORFs, with the 3’-terminal one corresponding to a protein of 209 amino acids (p23 that is expressed from an abundant subgenomic RNA. p23, an RNA-binding protein with a putative Zn-finger domain and some basic motifs, is unique to CTV because no homologues have been found in other closteroviruses, including the type species of the genus Beet yellows virus (despite both viruses having many homologous genes. Consequently, p23 might have evolved for the specific interaction of CTV with its citrus hosts. From a functional perspective p23 has been involved in many roles: i regulation of the asymmetrical accumulation of CTV RNA strands, ii induction of the seedling yellows syndrome in sour orange and grapefruit, iii intracellular suppression of RNA silencing, iv elicitation of CTV-like symptoms when expressed ectopically as a transgene in several Citrus spp., and v enhancement of systemic infection (and virus accumulation in sour orange and CTV release from the phloem in p23-expressing transgenic sweet and sour orange. Moreover, transformation of Mexican lime with intron-hairpin constructs designed for the co-inactivation of p23 and the two other CTV silencing suppressors results in complete resistance against the homologous virus. From a cellular point of view, recent data indicate that p23 accumulates preferentially in the nucleolus, being the first closterovirus protein with such a subcellular localization, as well as in plasmodesmata. These major accumulation sites most likely determine some of the functional roles of p23.

  7. Hepatitis C virus core protein induces hepatic steatosis via Sirt1-dependent pathway.

    Science.gov (United States)

    Zhang, Chuanhai; Wang, Jingjing; Zhang, Hanlin; Liu, Shunai; Lee, Hyuek Jong; Jin, Wanzhu; Cheng, Jun

    2017-09-12

    Hepatic steatosis is a common feature of patients with chronic hepatitis C. Previous reports have shown that the overexpression of hepatitis C virus core-encoding sequences (hepatitis C virus genotypes 3a and 1b) significantly induces intracellular triglyceride accumulation. However, the underlying mechanism has not yet been revealed. To investigate whether Sirt1 is involved in hepatitis C virus-mediated hepatic steatosis, the overexpression of hepatitis C virus core 1b protein and Sirt1 and the knockdown of Sirt1 in HepG2 cells were performed. To confirm the results of the cellular experiment liver-specific Sirt1 KO mice with lentivirus-mediated hepatitis C virus core 1b overexpression were studied. Our results show that hepatitis C virus core 1b protein overexpression led to the accumulation of triglycerides in HepG2 cells. Notably the expression of PPARγ2 was dramatically increased at both the mRNA and protein levels by hepatitis C virus core 1b overexpression. The protein expression of Sirt1 is an upstream regulator of PPARγ2 and was also significantly increased after core 1b overexpression. In addition, the overexpression or knockdown of Sirt1 expression alone was sufficient to modulate p300-mediated PPARγ2 deacetylation. In vivo studies showed that hepatitis C virus core protein 1b-induced hepatic steatosis was attenuated in liver-specific Sirt1 KO mice by downregulation of PPARγ2 expression. Sirt1 mediates hepatitis C virus core protein 1b-induced hepatic steatosis by regulation of PPARγ2 expression. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Identification, cloning, and expression analysis of three putative Lymantria dispar nuclear polyhedrosis virus immediate early genes

    Science.gov (United States)

    James M. Slavicek; Nancy Hayes-Plazolles

    1991-01-01

    Viral immediate early gene products are usually regulatory proteins that control expression of other viral genes at the transcriptional level or are proteins that are part of the viral DNA replication complex. The identification and functional characterization of the immediate early gene products of Lymantria dispar nuclear polyhedrosis virus (LdNPV...

  9. Diversity of matrix protein in subacute sclerosing panencephalitis and measles virus-infected cells.

    Science.gov (United States)

    Haga, T; Yoshikawa, Y; Yamanouchi, K

    1990-01-01

    Expression of the viral matrix (M) proteins in Vero cells infected with 18 strains of subacute sclerosing panencephalitis (SSPE) virus and measles virus was examined by immunocytochemistry and Western blot analysis using an anti-M monospecific serum and two sera against the M protein specific synthetic peptides. By immunocytochemistry using the anti-M monospecific serum, M protein was detected in all of the virus-infected cells regardless of cell-free virus production. M proteins of the seven non-productive strains were found to vary significantly in their epitope, in their reactivity to different assay systems, and in their molecular weight, whereas M proteins of the other 11 productive strains were detected consistently. These results suggest diversification of M protein of the non-productive strains.

  10. A protein kinase binds the C-terminal domain of the readthrough protein of Turnip yellows virus and regulates virus accumulation

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Medina, Caren; Boissinot, Sylvaine [UMR 1131 SVQV INRA-UDS, 28 rue de Herrlisheim, 68021 Colmar (France); Chapuis, Sophie [Institut de Biologie Moléculaire des Plantes, Laboratoire propre du CNRS conventionné avec l’Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg (France); Gereige, Dalya; Rastegar, Maryam; Erdinger, Monique [UMR 1131 SVQV INRA-UDS, 28 rue de Herrlisheim, 68021 Colmar (France); Revers, Frédéric [INRA, Université de Bordeaux, UMR 1332 de Biologie du Fruit et Pathologie, 33882 Villenave d’Ornon (France); Ziegler-Graff, Véronique [Institut de Biologie Moléculaire des Plantes, Laboratoire propre du CNRS conventionné avec l’Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg (France); Brault, Véronique, E-mail: veronique.brault@colmar.inra.fr [UMR 1131 SVQV INRA-UDS, 28 rue de Herrlisheim, 68021 Colmar (France)

    2015-12-15

    Turnip yellows virus (TuYV), a phloem-limited virus, encodes a 74 kDa protein known as the readthrough protein (RT) involved in virus movement. We show here that a TuYV mutant deleted of the C-terminal part of the RT protein (TuYV-∆RT{sub Cter}) was affected in long-distance trafficking in a host-specific manner. By using the C-terminal domain of the RT protein as a bait in a yeast two-hybrid screen of a phloem cDNA library from Arabidopsis thaliana we identified the calcineurin B-like protein-interacting protein kinase-7 (AtCIPK7). Transient expression of a GFP:CIPK7 fusion protein in virus-inoculated Nicotiana benthamiana leaves led to local increase of wild-type TuYV accumulation, but not that of TuYV-∆RT{sub Cter}. Surprisingly, elevated virus titer in inoculated leaves did not result in higher TuYV accumulation in systemic leaves, which indicates that virus long-distance movement was not affected. Since GFP:CIPK7 was localized in or near plasmodesmata, CIPK7 could negatively regulate TuYV export from infected cells. - Highlights: • The C-terminal domain of TuYV-RT is required for long-distance movement. • CIPK7 from Arabidopsis interacts with RT{sub Cter} in yeast and in plants. • CIPK7 overexpression increases virus titer locally but not virus systemic movement. • CIPK7 localizes to plasmodesmata. • CIPK7 could be a defense protein regulating virus export.

  11. Transgenic plums expressing the plum pox virus (PPV) coat protein gene do not assist the development of PPV recombinants under field conditions

    Science.gov (United States)

    The serological and molecular variability of Plum pox virus (PPV) detected in transgenic plum trees harboring PPV capsid gene versus those found in conventional plums were analyzed. Strain characterization was serologically determined by TAS-ELISA using PPV-D and PPV-M specific monoclonal antibodie...

  12. Field plot assessments demonstrate that transgenic plums expressing Plum pox virus (PPV) coat protein gene do not affect the PPV strain composition or produce PPV recombinants

    Science.gov (United States)

    The serological and molecular variability of Plum pox virus (PPV) detected in transgenic plum trees harboring PPV capsid gene versus those found in conventional plums were analyzed. Strain characterization was serologically determined by TAS-ELISA using PPV-D and PPV-M specific monoclonal antibodie...

  13. Recombinant subgroup B human respiratory syncytial virus expressing enhanced green fluorescent protein efficiently replicates in primary human cells and is virulent in cotton rats

    NARCIS (Netherlands)

    K. Lemon (Ken); D.T. Nguyen (Tien); M. Ludlow (Martin); L.J. Rennick (Linda); S. Yüksel (Selma); G. van Amerongen (Geert); S. McQuaid (Stephen); B.K. Rima (Bert); R.L. de Swart (Rik); W.P. Duprex (Paul)

    2015-01-01

    textabstractHuman respiratory syncytial virus (HRSV) is the most important viral cause of severe respiratory tract disease in infants. Two subgroups (A and B) have been identified, which cocirculate during, or alternate between, yearly epidemics and cause indistinguishable disease. Existing in vitro

  14. Data Mining for Expressivity of Recombinant Protein Expression

    Science.gov (United States)

    Kira, Satoshi; Isoai, Atsushi; Yamamura, Masayuki

    We analyzed the expressivity of recombinant proteins by using data mining methods. The expression technique of recombinant protein is a key step towards elucidating the functions of genes discovered through genomic sequence projects. We have studied the productive efficiency of recombinant proteins in fission yeast, Schizosaccharomyces pombe (S.pombe), by mining the expression results. We gathered 57 proteins whose expression levels were known roughly in the host. Correlation analysis, principal component analysis and decision tree analysis were applied to these expression data. Analysis featuring codon usage and amino acid composition clarified that the amino acid composition affected to the expression levels of a recombinant protein strongly than the effect of codon usage. Furthermore, analysis of amino acid composition showed that protein solubility and the metabolism cost of amino acids correlated with a protein expressivity. Codon usage was often interesting in the field of recombinant expressions. However, our analysis found the weak correlation codon features with expressivities. These results indicated that ready-made indices of codon bias were irrelevant ones for modeling the expressivities of recombinant proteins. Our data driven approach was an easy and powerful method to improve recombinant protein expression, and this approach should be concentrated attention with the huge amount of expression data accumulating through the post-genome era.

  15. Enhanced Transgene Expression in Sugarcane by Co-Expression of Virus-Encoded RNA Silencing Suppressors

    Science.gov (United States)

    Park, Jong-Won; Beyene, Getu; Buenrostro-Nava, Marco T.; Molina, Joe; Wang, Xiaofeng; Ciomperlik, Jessica J.; Manabayeva, Shuga A.; Alvarado, Veria Y.; Rathore, Keerti S.; Scholthof, Herman B.; Mirkov, T. Erik

    2013-01-01

    Post-transcriptional gene silencing is commonly observed in polyploid species and often poses a major limitation to plant improvement via biotechnology. Five plant viral suppressors of RNA silencing were evaluated for their ability to counteract gene silencing and enhance the expression of the Enhanced Yellow Fluorescent Protein (EYFP) or the β-glucuronidase (GUS) reporter gene in sugarcane, a major sugar and biomass producing polyploid. Functionality of these suppressors was first verified in Nicotiana benthamiana and onion epidermal cells, and later tested by transient expression in sugarcane young leaf segments and protoplasts. In young leaf segments co-expressing a suppressor, EYFP reached its maximum expression at 48–96 h post-DNA introduction and maintained its peak expression for a longer time compared with that in the absence of a suppressor. Among the five suppressors, Tomato bushy stunt virus-encoded P19 and Barley stripe mosaic virus-encoded γb were the most efficient. Co-expression with P19 and γb enhanced EYFP expression 4.6-fold and 3.6-fold in young leaf segments, and GUS activity 2.3-fold and 2.4-fold in protoplasts compared with those in the absence of a suppressor, respectively. In transgenic sugarcane, co-expression of GUS and P19 suppressor showed the highest accumulation of GUS levels with an average of 2.7-fold more than when GUS was expressed alone, with no detrimental phenotypic effects. The two established transient expression assays, based on young leaf segments and protoplasts, and confirmed by stable transgene expression, offer a rapid versatile system to verify the efficiency of RNA silencing suppressors that proved to be valuable in enhancing and stabilizing transgene expression in sugarcane. PMID:23799071

  16. Overexpression of Ebola virus envelope GP1 protein.

    Science.gov (United States)

    Zou, Zhongcheng; Misasi, John; Sullivan, Nancy; Sun, Peter D

    2017-07-01

    Ebola virus uses its envelope GP1 and GP2 for viral attachment and entry into host cells. Due to technical difficulty expressing full-length envelope, many structural and functional studies of Ebola envelope protein have been carried out primarily using GP1 lacking its mucin-like domain. As a result, the viral invasion mechanisms involving the mucin-like domain are not fully understood. To elucidate the role of the mucin-like domain of GP1 in Ebola-host attachment and infection and to facilitate vaccine development, we constructed a GP1 expression vector containing the entire attachment region (1-496). Cysteine 53 of GP1, which forms a disulfide bond with GP2, was mutated to serine to avoid potential disulfide bond mispairing. Stable expression clones using codon optimized open reading frame were developed in human 293-H cells with yields reaching ∼25 mg of GP1 protein per liter of spent medium. Purified GP1 was functional and bound to Ebola attachment receptors, DC-SIGN and DC-SIGNR. The over-expression and easy purification characteristic of this system has implications in Ebola research and vaccine development. To further understand the differential expression yields between the codon optimized and native GP1, we analyzed the presence of RNA structural motifs in the first 100 nucleotides of translational initiation AUG site. RNA structural prediction showed the codon optimization removed two potential RNA pseudoknot structures. This methodology is also applicable to the expression of other difficult virus envelope proteins. Published by Elsevier Inc.

  17. Plant RNA binding proteins for control of RNA virus infection

    Directory of Open Access Journals (Sweden)

    Sung Un eHuh

    2013-12-01

    Full Text Available Plant RNA viruses have effective strategies to infect host plants through either direct or indirect interactions with various host proteins, thus suppressing the host immune system. When plant RNA viruses enter host cells exposed RNAs of viruses are recognized by the host immune system through processes such as siRNA-dependent silencing. Interestingly, some host RNA binding proteins have been involved in the inhibition of RNA virus replication, movement, and translation through RNA-specific binding. Host plants intensively use RNA binding proteins for defense against viral infections in nature. In this mini review, we will summarize the function of some host RNA binding proteins which act in a sequence-specific binding manner to the infecting virus RNA. It is important to understand how plants effectively suppresses RNA virus infections via RNA binding proteins, and this defense system can be potentially developed as a synthetic virus defense strategy for use in crop engineering.

  18. Vaccinia Virus Recombinants: Expression of VSV Genes and Protective Immunization of Mice and Cattle

    Science.gov (United States)

    Mackett, M.; Yilma, T.; Rose, J. K.; Moss, B.

    1985-01-01

    Vesicular stomatitis virus (VSV) causes a contagious disease of horses, cattle, and pigs. When DNA copies of messenger RNA's for the G or N proteins of VSV were linked to a vaccinia virus promoter and inserted into the vaccinia genome, the recombinants retained infectivity and synthesized VSV polypeptides. After intradermal vaccination with live recombinant virus expressing the G protein, mice produced VSV-neutralizing antibodies and were protected against lethal encephalitis upon intravenous challenge with VSV. In cattle, the degree of protection against intradermalingually injected VSV was correlated with the level of neutralizing antibody produced following vaccination.

  19. Functional Evolution of Influenza Virus NS1 Protein in Currently Circulating Human 2009 Pandemic H1N1 Viruses.

    Science.gov (United States)

    Clark, Amelia M; Nogales, Aitor; Martinez-Sobrido, Luis; Topham, David J; DeDiego, Marta L

    2017-09-01

    In 2009, a novel H1N1 influenza virus emerged in humans, causing a global pandemic. It was previously shown that the NS1 protein from this human 2009 pandemic H1N1 (pH1N1) virus was an effective interferon (IFN) antagonist but could not inhibit general host gene expression, unlike other NS1 proteins from seasonal human H1N1 and H3N2 viruses. Here we show that the NS1 protein from currently circulating pH1N1 viruses has evolved to encode 6 amino acid changes (E55K, L90I, I123V, E125D, K131E, and N205S) with respect to the original protein. Notably, these 6 residue changes restore the ability of pH1N1 NS1 to inhibit general host gene expression, mainly by their ability to restore binding to the cellular factor CPSF30. This is the first report describing the ability of the pH1N1 NS1 protein to naturally acquire mutations that restore this function. Importantly, a recombinant pH1N1 virus containing these 6 amino acid changes in the NS1 protein (pH1N1/NSs-6mut) inhibited host IFN and proinflammatory responses to a greater extent than that with the parental virus (pH1N1/NS1-wt), yet virus titers were not significantly increased in cell cultures or in mouse lungs, and the disease was partially attenuated. The pH1N1/NSs-6mut virus grew similarly to pH1N1/NSs-wt in mouse lungs, but infection with pH1N1/NSs-6mut induced lower levels of proinflammatory cytokines, likely due to a general inhibition of gene expression mediated by the mutated NS1 protein. This lower level of inflammation induced by the pH1N1/NSs-6mut virus likely accounts for the attenuated disease phenotype and may represent a host-virus adaptation affecting influenza virus pathogenesis.IMPORTANCE Seasonal influenza A viruses (IAVs) are among the most common causes of respiratory infections in humans. In addition, occasional pandemics are caused when IAVs circulating in other species emerge in the human population. In 2009, a swine-origin H1N1 IAV (pH1N1) was transmitted to humans, infecting people then and up

  20. TIM-family proteins promote infection of multiple enveloped viruses through virion-associated phosphatidylserine.

    Directory of Open Access Journals (Sweden)

    Stephanie Jemielity

    2013-03-01

    Full Text Available Human T-cell Immunoglobulin and Mucin-domain containing proteins (TIM1, 3, and 4 specifically bind phosphatidylserine (PS. TIM1 has been proposed to serve as a cellular receptor for hepatitis A virus and Ebola virus and as an entry factor for dengue virus. Here we show that TIM1 promotes infection of retroviruses and virus-like particles (VLPs pseudotyped with a range of viral entry proteins, in particular those from the filovirus, flavivirus, New World arenavirus and alphavirus families. TIM1 also robustly enhanced the infection of replication-competent viruses from the same families, including dengue, Tacaribe, Sindbis and Ross River viruses. All interactions between TIM1 and pseudoviruses or VLPs were PS-mediated, as demonstrated with liposome blocking and TIM1 mutagenesis experiments. In addition, other PS-binding proteins, such as Axl and TIM4, promoted infection similarly to TIM1. Finally, the blocking of PS receptors on macrophages inhibited the entry of Ebola VLPs, suggesting that PS receptors can contribute to infection in physiologically relevant cells. Notably, infection mediated by the entry proteins of Lassa fever virus, influenza A virus and SARS coronavirus was largely unaffected by TIM1 expression. Taken together our data show that TIM1 and related PS-binding proteins promote infection of diverse families of enveloped viruses, and may therefore be useful targets for broad-spectrum antiviral therapies.

  1. TIM-family proteins promote infection of multiple enveloped viruses through virion-associated phosphatidylserine.

    Science.gov (United States)

    Jemielity, Stephanie; Wang, Jinyize J; Chan, Ying Kai; Ahmed, Asim A; Li, Wenhui; Monahan, Sheena; Bu, Xia; Farzan, Michael; Freeman, Gordon J; Umetsu, Dale T; Dekruyff, Rosemarie H; Choe, Hyeryun

    2013-03-01

    Human T-cell Immunoglobulin and Mucin-domain containing proteins (TIM1, 3, and 4) specifically bind phosphatidylserine (PS). TIM1 has been proposed to serve as a cellular receptor for hepatitis A virus and Ebola virus and as an entry factor for dengue virus. Here we show that TIM1 promotes infection of retroviruses and virus-like particles (VLPs) pseudotyped with a range of viral entry proteins, in particular those from the filovirus, flavivirus, New World arenavirus and alphavirus families. TIM1 also robustly enhanced the infection of replication-competent viruses from the same families, including dengue, Tacaribe, Sindbis and Ross River viruses. All interactions between TIM1 and pseudoviruses or VLPs were PS-mediated, as demonstrated with liposome blocking and TIM1 mutagenesis experiments. In addition, other PS-binding proteins, such as Axl and TIM4, promoted infection similarly to TIM1. Finally, the blocking of PS receptors on macrophages inhibited the entry of Ebola VLPs, suggesting that PS receptors can contribute to infection in physiologically relevant cells. Notably, infection mediated by the entry proteins of Lassa fever virus, influenza A virus and SARS coronavirus was largely unaffected by TIM1 expression. Taken together our data show that TIM1 and related PS-binding proteins promote infection of diverse families of enveloped viruses, and may therefore be useful targets for broad-spectrum antiviral therapies.

  2. Programmed ribosomal frameshift alters expression of west nile virus genes and facilitates virus replication in birds and mosquitoes.

    Directory of Open Access Journals (Sweden)

    Ezequiel Balmori Melian

    2014-11-01

    Full Text Available West Nile virus (WNV is a human pathogen of significant medical importance with close to 40,000 cases of encephalitis and more than 1,600 deaths reported in the US alone since its first emergence in New York in 1999. Previous studies identified a motif in the beginning of non-structural gene NS2A of encephalitic flaviviruses including WNV which induces programmed -1 ribosomal frameshift (PRF resulting in production of an additional NS protein NS1'. We have previously demonstrated that mutant WNV with abolished PRF was attenuated in mice. Here we have extended our previous observations by showing that PRF does not appear to have a significant role in virus replication, virion formation, and viral spread in several cell lines in vitro. However, we have also shown that PRF induces an over production of structural proteins over non-structural proteins in virus-infected cells and that mutation abolishing PRF is present in ∼11% of the wild type virus population. In vivo experiments in house sparrows using wild type and PRF mutant of New York 99 strain of WNV viruses showed some attenuation for the PRF mutant virus. Moreover, PRF mutant of Kunjin strain of WNV showed significant decrease compared to wild type virus infection in dissemination of the virus from the midgut through the haemocoel, and ultimately the capacity of infected mosquitoes to transmit virus. Thus our results demonstrate an important role for PRF in regulating expression of viral genes and consequently virus replication in avian and mosquito hosts.

  3. Influence of temperature on symptom expression, detection of host factors in virus infected Piper nigrum L.

    Science.gov (United States)

    Umadevi, P; Bhat, A I; Krishnamurthy, K S; Anandaraj, M

    2016-05-01

    Expression of symptoms in black pepper plants (Piper nigrum) infected with Piper yellow mottle virus (PYMoV) vary depending on the season, being high during summer months. Here, we explored the influence of temperature on symptom expression in PYMoV infected P. nigrum. Our controlled environment study revealed increase in virus titer, total proteins, IAA and reducing sugars when exposed to temperature stress. There was change in the 2-D separated protein before and after exposure. The 2-D proteomics LC-MS identified host and viral proteins suggesting virus-host interaction during symptom expression. The analysis as well as detection of host biochemical compounds may help in understanding the detailed mechanisms underlying the viral replication and damage to the crop, and thereby plan management strategies.

  4. Attenuation of vaccinia virus by the expression of human Flt3 ligand

    Directory of Open Access Journals (Sweden)

    Sanda Miloslav

    2010-05-01

    Full Text Available Abstract Background Vaccinia virus, one of the best known members of poxvirus family, has a wide host range both in vivo and in vitro. The expression of Flt3 ligand (FL by recombinant vaccinia virus (rVACV highly influenced properties of the virus in dependence on the level of expression. Results High production of FL driven by the strong synthetic promoter decreased the growth of rVACV in macrophage cell line J774.G8 in vitro as well as its multiplication in vivo when inoculated in mice. The inhibition of replication in vivo was mirrored in low levels of antibodies against vaccinia virus (anti-VACV which nearly approached to the negative serum level in non-infected mice. Strong FL expression changed not only the host range of the recombinant but also the basic protein contents of virions. The major proteins - H3L and D8L - which are responsible for the virus binding to the cells, and 28 K protein that serves as a virulence factor, were changed in the membrane portion of P13-E/L-FL viral particles. The core virion fraction contained multiple larger, uncleaved proteins and a higher amount of cellular proteins compared to the control virus. The overexpression of FL also resulted in its incorporation into the viral core of P13-E/L-FL IMV particles. In contrary to the equimolar ratio of glycosylated and nonglycosylated FL forms found in cells transfected with the expression plasmid, the recombinant virus incorporated mainly the smaller, nonglycosylated FL. Conclusions It has been shown that the overexpression of the Flt3L gene in VACV results in the attenuation of the virus in vivo.

  5. Pseudotype formation of murine leukemia virus with the G protein of vesicular stomatitis virus.

    OpenAIRE

    Emi, N; Friedmann, T; Yee, J K

    1991-01-01

    Mixed infection of a cell by vesicular stomatitis virus (VSV) and retroviruses results in the production of progeny virions bearing the genome of one virus encapsidated by the envelope proteins of the other. The mechanism for the phenomenon of pseudotype formation is not clear, although specific recognition of a viral envelope protein by the nucleocapsid of an unrelated virus is presumably involved. In this study, we used Moloney murine leukemia virus (MoMLV)-based retroviral vectors encoding...

  6. Protein and modified vaccinia virus Ankara-based influenza virus nucleoprotein vaccines are differentially immunogenic in BALB/c mice.

    Science.gov (United States)

    Altenburg, A F; Magnusson, S E; Bosman, F; Stertman, L; de Vries, R D; Rimmelzwaan, G F

    2017-10-01

    Because of the high variability of seasonal influenza viruses and the eminent threat of influenza viruses with pandemic potential, there is great interest in the development of vaccines that induce broadly protective immunity. Most probably, broadly protective influenza vaccines are based on conserved proteins, such as nucleoprotein (NP). NP is a vaccine target of interest as it has been shown to induce cross-reactive antibody and T cell responses. Here we tested and compared various NP-based vaccine preparations for their capacity to induce humoral and cellular immune responses to influenza virus NP. The immunogenicity of protein-based vaccine preparations with Matrix-M™ adjuvant as well as recombinant viral vaccine vector modified Vaccinia virus Ankara (MVA) expressing the influenza virus NP gene, with or without modifications that aim at optimization of CD8 + T cell responses, was addressed in BALB/c mice. Addition of Matrix-M™ adjuvant to NP wild-type protein-based vaccines significantly improved T cell responses. Furthermore, recombinant MVA expressing the influenza virus NP induced strong antibody and CD8 + T cell responses, which could not be improved further by modifications of NP to increase antigen processing and presentation. © 2017 British Society for Immunology.

  7. Fabrication and characterization of gold nano-wires templated on virus-like arrays of tobacco mosaic virus coat proteins

    Science.gov (United States)

    Wnęk, M.; Górzny, M. Ł.; Ward, M. B.; Wälti, C.; Davies, A. G.; Brydson, R.; Evans, S. D.; Stockley, P. G.

    2013-01-01

    The rod-shaped plant virus tobacco mosaic virus (TMV) is widely used as a nano-fabrication template, and chimeric peptide expression on its major coat protein has extended its potential applications. Here we describe a simple bacterial expression system for production and rapid purification of recombinant chimeric TMV coat protein carrying C-terminal peptide tags. These proteins do not bind TMV RNA or form disks at pH 7. However, they retain the ability to self-assemble into virus-like arrays at acidic pH. C-terminal peptide tags in such arrays are exposed on the protein surface, allowing interaction with target species. We have utilized a C-terminal His-tag to create virus coat protein-templated nano-rods able to bind gold nanoparticles uniformly. These can be transformed into gold nano-wires by deposition of additional gold atoms from solution, followed by thermal annealing. The resistivity of a typical annealed wire created by this approach is significantly less than values reported for other nano-wires made using different bio-templates. This expression construct is therefore a useful additional tool for the creation of chimeric TMV-like nano-rods for bio-templating.

  8. Vaccinia virus as an expression vector.

    Science.gov (United States)

    Talavera, A; Rodriguez, J M

    1992-01-01

    Vaccinia virus (Vv) is a member of the genus Orthopoxvirus, one of seven genera included in the family Poxviridae. Most of these viruses infect vertebrates (Orthopoxvirus, Avipoxvirus, Capripoxvirus, Leporipoxvirus, Suipoxvirus, and Parapoxvirus), but one genus, Entomopoxvirus, infects insects. It is interesting to note that the Fibroma and Mixoma viruses of the leporipoxvirus genus cause tumors in their hosts (rabbits), these being the only tumorigenic viruses in the family (1,2).

  9. Recent patents involving virus nucleotide sequences; host defense, RNA silencing and expression vector strategies.

    Science.gov (United States)

    Ahmad, Tauqeer; AbouHaidar, Mounir; Hefferon, Kathleen L

    2011-12-01

    Improved knowledge of the molecular biology of viruses, including recent gains in virus sequence data analysis, has greatly contributed to recent innovations in medical diagnostics, therapeutics, drug development and other related areas. Virus sequences have been used for the development of vaccines and antiviral agents to block the spread of viral infections, as well as to target and battle chronic diseases such as cancer. Virus sequences are now routinely employed in a wide array of RNA silencing technologies. Viruses can also be engineered into expression vectors which in turn can be used as protein production platforms as well as delivery vehicles for gene therapies. This review article outlines a number of patents that have been recently issued with respect to virus sequence data and describes some of their biotechnological applications.

  10. Intracellular localization and movement phenotypes of alfalfa mosaic virus movement protein mutants

    NARCIS (Netherlands)

    Huang, M.; Jongejan, L.; Zheng, H.; Zhang, L.; Bol, J. F.

    2001-01-01

    Thirteen mutations were introduced in the movement protein (MP) gene of Alfalfa mosaic virus (AMV) fused to the green fluorescent protein (GFP) gene and the mutant MP-GFP fusions were expressed transiently in tobacco protoplasts, tobacco suspension cells, and epidermal cells of tobacco leaves. In

  11. Tomato spotted wilt virus Gc and N proteins interact in vivo

    NARCIS (Netherlands)

    Snippe, M.; Borst, J.W.; Goldbach, R.W.; Kormelink, R.J.M.

    2007-01-01

    Tomato spotted wilt virus (TSWV) virions consist of a nucleocapsid core surrounded by a membrane containing glycoproteins Gn and Gc. To unravel the protein interactions involved in the membrane acquisition of RNPs, TSWV nucleocapsid protein (N), Gn and Gc were expressed and analyzed in BHK21 cells.

  12. The Major Capsid Protein of Herpes Simplex Virus-1 Affects its

    African Journals Online (AJOL)

    rate rose to 85 % compared with virus control. Knocking down VP5 expression abrogated the changes to F-actin that were induced by HSV-1 infection. Conclusion: Interfering with UL19 gene expression inhibits HSV-1 replication efficiently in vitro. The results indicate that the major capsid protein VP5 encoding gene UL19 ...

  13. Expression of an extracellular ribonuclease gene increases resistance to Cucumber mosaic virus in tobacco

    Directory of Open Access Journals (Sweden)

    Teppei Sugawara

    2016-11-01

    Full Text Available Abstract Background The apoplast plays an important role in plant defense against pathogens. Some extracellular PR-4 proteins possess ribonuclease activity and may directly inhibit the growth of pathogenic fungi. It is likely that extracellular RNases can also protect plants against some viruses with RNA genomes. However, many plant RNases are multifunctional and the direct link between their ribonucleolytic activity and antiviral defense still needs to be clarified. In this study, we evaluated the resistance of Nicotiana tabacum plants expressing a non-plant single-strand-specific extracellular RNase against Cucumber mosaic virus. Results Severe mosaic symptoms and shrinkage were observed in the control non-transgenic plants 10 days after inoculation with Cucumber mosaic virus (CMV, whereas such disease symptoms were suppressed in the transgenic plants expressing the RNase gene. In a Western blot analysis, viral proliferation was observed in the uninoculated upper leaves of control plants, whereas virus levels were very low in those of transgenic plants. These results suggest that resistance against CMV was increased by the expression of the heterologous RNase gene. Conclusion We have previously shown that tobacco plants expressing heterologous RNases are characterized by high resistance to Tobacco mosaic virus. In this study, we demonstrated that elevated levels of extracellular RNase activity resulted in increased resistance to a virus with a different genome organization and life cycle. Thus, we conclude that the pathogen-induced expression of plant apoplastic RNases may increase non-specific resistance against viruses with RNA genomes.

  14. Mumps Virus Decreases Testosterone Production and Gamma Interferon-Induced Protein 10 Secretion by Human Leydig Cells

    OpenAIRE

    Le Goffic, Ronan; Mouchel, Thomas; Ruffault, Annick; Patard, Jean-Jacques; Jégou, Bernard; Samson, Michel

    2003-01-01

    Mumps virus is responsible for sterility. Here, we show that the mumps virus infects Leydig cells in vitro and totally inhibits testosterone secretion and that ribavirin in mumps virus-infected Leydig cell cultures completely restores testosterone production. Moreover, we show that gamma interferon-induced protein 10 (IP-10) is highly expressed by mumps virus-infected Leydig cells and that ribavirin does not block IP-10 production.

  15. Nanoparticulate architecture of protein-based artificial viruses is supported by protein-DNA interactions.

    Science.gov (United States)

    Domingo-Espín, Joan; Vazquez, Esther; Ganz, Javier; Conchillo, Oscar; García-Fruitós, Elena; Cedano, Juan; Unzueta, Ugutz; Petegnief, Valérie; Gonzalez-Montalbán, Nuria; Planas, Anna M; Daura, Xavier; Peluffo, Hugo; Ferrer-Miralles, Neus; Villaverde, Antonio

    2011-08-01

    AIM & METHODS: We have produced two chimerical peptides of 10.2 kDa, each contain four biologically active domains, which act as building blocks of protein-based nonviral vehicles for gene therapy. In solution, these peptides tend to aggregate as amorphous clusters of more than 1000 nm, while the presence of DNA promotes their architectonic reorganization as mechanically stable nanometric spherical entities of approximately 80 nm that penetrate mammalian cells through arginine-glycine-aspartic acid cell-binding domains and promote significant transgene expression levels. The structural analysis of the protein in these hybrid nanoparticles indicates a molecular conformation with predominance of α-helix and the absence of cross-molecular, β-sheet-supported protein interactions. The nanoscale organizing forces generated by DNA-protein interactions can then be observed as a potentially tunable, critical factor in the design of protein-only based artificial viruses for gene therapy.

  16. A novel recombinant pseudorabies virus expressing parvovirus VP2 gene: Immunogenicity and protective efficacy in swine

    Science.gov (United States)

    2011-01-01

    Background Porcine parvovirus (PPV) VP2 gene has been successfully expressed in many expression systems resulting in self-assembly of virus-like particles (VLPs) with similar morphology to the native capsid. Here, a pseudorabies virus (PRV) system was adopted to express the PPV VP2 gene. Methods A recombinant PRV SA215/VP2 was obtained by homologous recombination between the vector PRV viral DNA and a transfer plasmid. Then recombinant virus was purified with plaque purification, and its identity confirmed by PCR amplification, Western blot and indirect immunofluorescence (IFA) analyses. Electronic microscopy of PRV SA215/VP2 confirmed self-assembly of both pseudorabies virus and VLPs from VP2 protein. Results Immunization of piglets with recombinant virus elicited PRV-specific and PPV-specific humoral immune responses and provided complete protection against a lethal dose of PRV challenges. Gilts immunized with recombinant viruses induced PPV-specific antibodies, and significantly reduced the mortality rate of (1 of 28) following virulent PPV challenge compared with the control (7 of 31). Furthermore, PPV virus DNA was not detected in the fetuses of recombinant virus immunized gilts. Conclusions In this study, a recombinant PRV SA215/VP2 virus expressing PPV VP2 protein was constructed using PRV SA215 vector. The safety, immunogenicity, and protective efficacy of the recombinant virus were demonstrated in piglets and primiparous gilts. This recombinant PRV SA215/VP2 represents a suitable candidate for the development of a bivalent vaccine against both PRV and PPV infection. PMID:21679423

  17. A novel recombinant pseudorabies virus expressing parvovirus VP2 gene: Immunogenicity and protective efficacy in swine

    Directory of Open Access Journals (Sweden)

    Chen Dishi

    2011-06-01

    Full Text Available Abstract Background Porcine parvovirus (PPV VP2 gene has been successfully expressed in many expression systems resulting in self-assembly of virus-like particles (VLPs with similar morphology to the native capsid. Here, a pseudorabies virus (PRV system was adopted to express the PPV VP2 gene. Methods A recombinant PRV SA215/VP2 was obtained by homologous recombination between the vector PRV viral DNA and a transfer plasmid. Then recombinant virus was purified with plaque purification, and its identity confirmed by PCR amplification, Western blot and indirect immunofluorescence (IFA analyses. Electronic microscopy of PRV SA215/VP2 confirmed self-assembly of both pseudorabies virus and VLPs from VP2 protein. Results Immunization of piglets with recombinant virus elicited PRV-specific and PPV-specific humoral immune responses and provided complete protection against a lethal dose of PRV challenges. Gilts immunized with recombinant viruses induced PPV-specific antibodies, and significantly reduced the mortality rate of (1 of 28 following virulent PPV challenge compared with the control (7 of 31. Furthermore, PPV virus DNA was not detected in the fetuses of recombinant virus immunized gilts. Conclusions In this study, a recombinant PRV SA215/VP2 virus expressing PPV VP2 protein was constructed using PRV SA215 vector. The safety, immunogenicity, and protective efficacy of the recombinant virus were demonstrated in piglets and primiparous gilts. This recombinant PRV SA215/VP2 represents a suitable candidate for the development of a bivalent vaccine against both PRV and PPV infection.

  18. The E4 protein; structure, function and patterns of expression

    Energy Technology Data Exchange (ETDEWEB)

    Doorbar, John, E-mail: jdoorba@nimr.mrc.ac.uk

    2013-10-15

    The papillomavirus E4 open reading frame (ORF) is contained within the E2 ORF, with the primary E4 gene-product (E1{sup ∧}E4) being translated from a spliced mRNA that includes the E1 initiation codon and adjacent sequences. E4 is located centrally within the E2 gene, in a region that encodes the E2 protein′s flexible hinge domain. Although a number of minor E4 transcripts have been reported, it is the product of the abundant E1{sup ∧}E4 mRNA that has been most extensively analysed. During the papillomavirus life cycle, the E1{sup ∧}E4 gene products generally become detectable at the onset of vegetative viral genome amplification as the late stages of infection begin. E4 contributes to genome amplification success and virus synthesis, with its high level of expression suggesting additional roles in virus release and/or transmission. In general, E4 is easily visualised in biopsy material by immunostaining, and can be detected in lesions caused by diverse papillomavirus types, including those of dogs, rabbits and cattle as well as humans. The E4 protein can serve as a biomarker of active virus infection, and in the case of high-risk human types also disease severity. In some cutaneous lesions, E4 can be expressed at higher levels than the virion coat proteins, and can account for as much as 30% of total lesional protein content. The E4 proteins of the Beta, Gamma and Mu HPV types assemble into distinctive cytoplasmic, and sometimes nuclear, inclusion granules. In general, the E4 proteins are expressed before L2 and L1, with their structure and function being modified, first by kinases as the infected cell progresses through the S and G2 cell cycle phases, but also by proteases as the cell exits the cell cycle and undergoes true terminal differentiation. The kinases that regulate E4 also affect other viral proteins simultaneously, and include protein kinase A, Cyclin-dependent kinase, members of the MAP Kinase family and protein kinase C. For HPV16 E1{sup

  19. Development of dengue virus replicons expressing HIV-1 gp120 and other heterologous genes: a potential future tool for dual vaccination against dengue virus and HIV

    Directory of Open Access Journals (Sweden)

    Dayton Andrew I

    2001-11-01

    Full Text Available Abstract Background Toward the goals of providing an additional vector to add to the armamentarium available to HIV vaccinologists and of creating a bivalent vaccine effective against dengue virus and HIV, we have attempted to create vectors which express dengue virus non-structural proteins and HIV immunogens. Previously we reported the successful construction of dengue virus replicons which lack structural genes necessary for virion release and spreading infection in culture but which can replicate intracellularly and abundantly produce dengue non-structural proteins. Here we attempted to express heterologous genetic material from these replicons. Results We cloned into a Δpre-M/E dengue virus replicon genes for either green fluorescent protein (GFP, HIV gp160 or HIV gp120 and tested the ability of these constructs to express dengue virus proteins as well as the heterologous proteins in tissue culture after transfection of replicon RNA. Conclusions Heterologous proteins were readily expressed from these constructs. GFP and gp120 demonstrated minimal or no toxicity. Gp160 expressing replicons were found to express proteins abundantly at 36 hours post transfection, but after 50 hrs of transfection, few replicon positive cells could be found despite the presence of cellular debris positive for replicon proteins. This suggested that gp160 expressed from dengue virus replicons is considerably more toxic than either GFP or gp120. The successful expression of heterologous proteins, including HIV gp120 for long periods in culture suggests this vector system may be useful as a vaccine vector, given appropriate delivery methods.

  20. Effect of Phosphorylation of CM2 Protein on Influenza C Virus Replication.

    Science.gov (United States)

    Goto, Takanari; Shimotai, Yoshitaka; Matsuzaki, Yoko; Muraki, Yasushi; Sho, Ri; Sugawara, Kanetsu; Hongo, Seiji

    2017-11-15

    CM2 is the second membrane protein of the influenza C virus and has been demonstrated to play a role in the uncoating and genome packaging processes in influenza C virus replication. Although the effects of N-linked glycosylation, disulfide-linked oligomerization, and palmitoylation of CM2 on virus replication have been analyzed, the effect of the phosphorylation of CM2 on virus replication remains to be determined. In this study, a phosphorylation site(s) at residue 78 and/or 103 of CM2 was replaced with an alanine residue(s), and the effects of the loss of phosphorylation on influenza C virus replication were analyzed. No significant differences were observed in the packaging of the reporter gene between influenza C virus-like particles (VLPs) produced from 293T cells expressing wild-type CM2 and those from the cells expressing the CM2 mutants lacking the phosphorylation site(s). Reporter gene expression in HMV-II cells infected with VLPs containing the CM2 mutants was inhibited in comparison with that in cells infected with wild-type VLPs. The virus production of the recombinant influenza C virus possessing CM2 mutants containing a serine-to-alanine change at residue 78 was significantly lower than that of wild-type recombinant influenza C virus. Furthermore, the virus growth of the recombinant viruses possessing CM2 with a serine-to-aspartic acid change at position 78, to mimic constitutive phosphorylation, was virtually identical to that of the wild-type virus. These results suggest that phosphorylation of CM2 plays a role in efficient virus replication, probably through the addition of a negative charge to the Ser78 phosphorylation site. IMPORTANCE It is well-known that many host and viral proteins are posttranslationally modified by phosphorylation, which plays a role in the functions of these proteins. In influenza A and B viruses, phosphorylation of viral proteins NP, M1, NS1, and the nuclear export protein (NEP), which are not integrated into the

  1. Modulation of the myxoma virus plaque phenotype by vaccinia virus protein F11.

    Science.gov (United States)

    Irwin, Chad R; Evans, David H

    2012-07-01

    Vaccinia virus (VACV) produces large plaques consisting of a rapidly expanding ring of infected cells surrounding a lytic core, whereas myxoma virus (MYXV) produces small plaques that resemble a focus of transformed cells. This is odd, because bioinformatics suggests that MYXV carries homologs of nearly all of the genes regulating Orthopoxvirus attachment, entry, and exit. So why does MYXV produce foci? One notable difference is that MYXV-infected cells produce few of the actin microfilaments that promote VACV exit and spread. This suggested that although MYXV carries homologs of the required genes (A33R, A34R, A36R, and B5R), they are dysfunctional. To test this, we produced MYXV recombinants expressing these genes, but we could not enhance actin projectile formation even in cells expressing all four VACV proteins. Another notable difference between these viruses is that MYXV lacks a homolog of the F11L gene. F11 inhibits the RhoA-mDia signaling that maintains the integrity of the cortical actin layer. We constructed an MYXV strain encoding F11L and observed that, unlike wild-type MYXV, the recombinant virus disrupted actin stress fibers and produced plaques up to 4-fold larger than those of controls, and these plaques expanded ∼6-fold faster. These viruses also grew to higher titers in multistep growth conditions, produced higher levels of actin projectiles, and promoted infected cell movement, although neither process was to the extent of that observed in VACV-infected cells. Thus, one reason for why MYXV produces small plaques is that it cannot spread via actin filaments, although the reason for this deficiency remains obscure. A second reason is that leporipoxviruses lack vaccinia's capacity to disrupt cortical actin.

  2. Proteomic analysis of the herpes simplex virus 1 virion protein 16 transactivator protein in infected cells.

    Science.gov (United States)

    Suk, Hyung; Knipe, David M

    2015-06-01

    The herpes simplex virus 1 virion protein 16 (VP16) tegument protein forms a transactivation complex with the cellular proteins host cell factor 1 (HCF-1) and octamer-binding transcription factor 1 (Oct-1) upon entry into the host cell. VP16 has also been shown to interact with a number of virion tegument proteins and viral glycoprotein H to promote viral assembly, but no comprehensive study of the VP16 proteome has been performed at early times postinfection. We therefore performed a proteomic analysis of VP16-interacting proteins at 3 h postinfection. We confirmed the interaction of VP16 with HCF-1 and a large number of cellular Mediator complex proteins, but most surprisingly, we found that the major viral protein associating with VP16 is the infected cell protein 4 (ICP4) immediate-early (IE) transactivator protein. These results raise the potential for a new function for VP16 in associating with the IE ICP4 and playing a role in transactivation of early and late gene expression, in addition to its well-documented function in transactivation of IE gene expression. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Functional characterization of the vaccinia virus I5 protein

    Directory of Open Access Journals (Sweden)

    Stanitsa Eleni S

    2008-12-01

    Full Text Available The I5L gene is one of ~90 genes that are conserved throughout the chordopoxvirus family, and hence are presumed to play vital roles in the poxvirus life cycle. Previous work had indicated that the VP13 protein, a component of the virion membrane, was encoded by the I5L gene, but no additional studies had been reported. Using a recombinant virus that encodes an I5 protein fused to a V5 epitope tag at the endogenous locus (vI5V5, we show here that the I5 protein is expressed as a post-replicative gene and that the ~9 kDa protein does not appear to be phosphorylated in vivo. I5 does not appear to traffic to any cellular organelle, but ultrastructural and biochemical analyses indicate that I5 is associated with the membranous components of assembling and mature virions. Intact virions can be labeled with anti-V5 antibody as assessed by immunoelectron microscopy, indicating that the C' terminus of the protein is exposed on the virion surface. Using a recombinant virus which encodes only a TET-regulated copy of the I5V5 gene (vΔindI5V5, or one in which the I5 locus has been deleted (vΔI5, we also show that I5 is dispensable for replication in tissue culture. Neither plaque size nor the viral yield produced in BSC40 cells or primary human fibroblasts are affected by the absence of I5 expression.

  4. Oncogenic Potential of Hepatitis C Virus Proteins

    Directory of Open Access Journals (Sweden)

    Ranjit Ray

    2010-09-01

    Full Text Available Chronic hepatitis C virus (HCV infection is a major risk factor for liver disease progression, and may lead to cirrhosis and hepatocellular carcinoma (HCC. The HCV genome contains a single-stranded positive sense RNA with a cytoplasmic lifecycle. HCV proteins interact with many host-cell factors and are involved in a wide range of activities, including cell cycle regulation, transcriptional regulation, cell proliferation, apoptosis, lipid metabolism, and cell growth promotion. Increasing experimental evidences suggest that HCV contributes to HCC by modulating pathways that may promote malignant transformation of hepatocytes. At least four of the 10 HCV gene products, namely core, NS3, NS5A and NS5B play roles in several potentially oncogenic pathways. Induction of both endoplasmic reticulum (ER stress and oxidative stress by HCV proteins may also contribute to hepatocyte growth promotion. The current review identifies important functions of the viral proteins connecting HCV infections and potential for development of HCC. However, most of the putative transforming potentials of the HCV proteins have been defined in artificial cellular systems, and need to be established relevant to infection and disease models. The new insight into the mechanisms for HCV mediated disease progression may offer novel therapeutic targets for one of the most devastating human malignancies in the world today.

  5. Optimization the expression of human papilloma virus E6 and E7 polytopic construct in E. coli expression system

    Directory of Open Access Journals (Sweden)

    Arian Rahimi

    2015-12-01

    Full Text Available Background: Human papilloma virus is a DNA virus from the papillomavirus family that is most prevalent in human cervical cancers and many studies showed the E6 and E7 proteins are present in the majority of cervical cancer cases. Development of universal HPV peptide-based vaccine with more serotypes coverage has considerable value. The aim of the study was to design a multi-epitope universal vaccine for major HPV based on E6 and E7 proteins and optimization the expression of polytopic construct contains E6 and E7 genes from different genotypes of human papilloma virus as a candid vaccine. Methods: In this experimental study that was carried out in Pasteur Institute of Iran, Virology Department from October 2013 to November 2014. In order to design the polytypic construct, we predicted the most probable immunogenic epitopes of E6 and E7 from common high risk HPV16, 18, 31, 45 along with high prevalent type 6 and 11 using bioinformatics methods. The synthetic pET28a expression vector harboring E6 and E7 protein was transformed into Escherichia coli hosts and its expression was analyzed by SDS-PAGE and western blotting. Finally, in order to expression optimization of recombinant protein, cell density, induction time, growth temperature, IPTG (Isopropyl β-D-1-thiogalactopyranoside concentration and cultures media were studied. Results: In the present study the recombinant fusion protein was expressed successfully and the highest expression of target protein was achieved in super broth medium containing 0.1% glucose and 0.2% L-arabinose. In Super broth medium, the optimum condition for recombinant protein expression was occurred at OD600 of 0.8, 0.1mM IPTG, one hour’s incubation time at 37 °C and BL21 (A1 host. Conclusion: The results of this study show that the optimum expression of E6 and E7 proteins from different genotypes of human papilloma virus can be performed. Moreover, by purification of recombinant protein and evaluation of its

  6. Generation of Recombinant Schmallenberg Virus Nucleocapsid Protein in Yeast and Development of Virus-Specific Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Justas Lazutka

    2014-01-01

    Full Text Available Schmallenberg virus (SBV, discovered in continental Europe in late 2011, causes mild clinical signs in adult ruminants, including diarrhoea and reduced milk yield. However, fetal infection can lead to severe malformation in newborn offspring. To develop improved reagents for SBV serology, a high-level yeast expression system was employed to produce recombinant SBV nucleocapsid (N protein. Recombinant SBV N protein was investigated as an antigen in SBV-specific IgG enzyme immunoassay and used for generation of monoclonal antibodies (MAbs. Yeast-expressed SBV N protein was reactive with anti-SBV IgG-positive cow serum specimens collected from different farms of Lithuania. After immunization of mice with recombinant SBV N protein, four MAbs were generated. The MAbs raised against recombinant SBV N protein reacted with native viral nucleocapsids in SBV-infected BHK cells by immunofluorescence assay. The reactivity of recombinant N protein with SBV-positive cow serum specimens and the ability of the MAbs to recognize virus-infected cells confirm the antigenic similarity between yeast-expressed SBV N protein and native viral nucleocapsids. Our study demonstrates that yeast expression system is suitable for high-level production of recombinant SBV N protein and provides the first evidence on the presence of SBV-specific antibodies in cow serum specimens collected in Lithuania.

  7. Expression of Human papillomavirus 16 E7ggg oncoprotein on N- and C-terminus of Potato virus X coat protein in bacterial and plant cells

    Czech Academy of Sciences Publication Activity Database

    Plchová, Helena; Moravec, Tomáš; Hoffmeisterová, Hana; Folwarczna, Jitka; Čeřovská, Noemi

    2011-01-01

    Roč. 77, č. 2 (2011), s. 146-152 ISSN 1046-5928 R&D Projects: GA ČR GA521/09/1525 Institutional research plan: CEZ:AV0Z50380511 Keywords : Bacterial expression * Human papillomavirus * Oncoprotein E7 Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.587, year: 2011

  8. Development of a versatile oncolytic virus platform for local intra-tumoural expression of therapeutic transgenes.

    Science.gov (United States)

    Marino, Nalini; Illingworth, Sam; Kodialbail, Prithvi; Patel, Ashvin; Calderon, Hugo; Lear, Rochelle; Fisher, Kerry D; Champion, Brian R; Brown, Alice C N

    2017-01-01

    Oncolytic viruses which infect and kill tumour cells can also be genetically modified to express therapeutic genes that augment their anti-cancer activities. Modifying oncolytic viruses to produce effective cancer therapies is challenging as encoding transgenes often attenuates virus activity or prevents systemic delivery in patients due to the risk of off-target expression of transgenes in healthy tissues. To overcome these issues we aimed to generate a readily modifiable virus platform using the oncolytic adenovirus, enadenotucirev. Enadenotucirev replicates in human tumour cells but not cells from healthy tissues and can be delivered intravenously because it is stable in human blood. Here, the enadenotucirev genome was used to generate plasmids into which synthesised transgene cassettes could be directly cloned in a single step reaction. The platform enabled generation of panels of reporter viruses to identify cloning sites and transgene cassette designs where transgene expression could be linked to the virus life cycle. It was demonstrated using these viruses that encoded transgene proteins could be successfully expressed in tumour cells in vitro and tumours in vivo. The expression of transgenes did not impact either the oncolytic activity or selective properties of the virus. The effectiveness of this approach as a drug delivery platform for complex therapeutics was demonstrated by inserting multiple genes in the virus genome to encode full length anti-VEGF antibodies. Functional antibody could be synthesised and secreted from infected tumour cells without impacting the activity of the virus particle in terms of oncolytic potency, manufacturing yields or selectivity for tumour cells. In vivo, viral particles could be efficaciously delivered intravenously to disseminated orthotopic tumours.

  9. [Differences of the regulation on the expression of mucin 1 induced by two single-strand RNA viruses, respiratory syncytial virus and influenza virus].

    Science.gov (United States)

    Lu, Xin; Ni, Shu-Yuan; Li, Yu-Sheng

    2012-11-01

    To investigate whether influenza virus (IFZ) could up-regulate the expression of mucin 1 (MUC1) which exists in epithelial cells of upper respiratory track to restrict the inflammation, as respiratory syncytial virus (RSV) does. Quantitative RT-PCR and Western Blot were performed to detect the expression level of MUC1 induced by two single-strand RNA viruses in A549 cell lines. HEp-2 and MDCK cells were used respectively to culture RSV and IFZ. At 24h post A549 cells infection with the same titer of RSV or IFZ, the total RNA was harvest, qRT-PCR was then performed to observe the expression level of MUC1 mRNA. Meanwhile, at 24 h and 48 h post A549 cells infection with the same titer of RSV or IFZ, the total protein and supernatant were collected respectively after cell lysis, Western Blot was then used to detect the expression level of MUC1. Results showed that RSV could up-regulate the expression of MUC1 in airway epithelial cells with a significant dose-effect correlation, whereas IFZ could not. This study firstly investigated the differences of the regulation on the expression of MUC1 induced by two single-strand RNA viruses, and demonstrated initially that the mechanism of IFZ self-limiting differed from RSV, which attributed to up-regulation of the expression level of MUC1.

  10. Tubule-forming capacity of the movement proteins of alfalfa mosaic virus and brome mosaic virus

    NARCIS (Netherlands)

    Kasteel, D. T.; van der Wel, N. N.; Jansen, K. A.; Goldbach, R. W.; van Lent, J. W.

    1997-01-01

    The structural phenotype of the movement proteins (MPs) of two representatives of the Bromoviridae, alfalfa mosaic virus (AMV) and brome mosaic virus (BMV), was studied in protoplasts. Immunofluorescence microscopy showed that the MPs of these viruses, for which there has been no evidence of a

  11. Proteins synthesized in tobacco mosaic virus infected protoplasts

    NARCIS (Netherlands)

    Huber, R.

    1979-01-01

    The study described here concerns the proteins, synthesized as a result of tobacco mosaic virus (TMV) multiplication in tobacco protoplasts and in cowpea protoplasts. The identification of proteins involved in the TMV infection, for instance in the virus RNA replication, helps to elucidate

  12. The use of fluorescence microscopy to visualise homotypic interactions of tomato spotted wilt virus nucleocapsid protein in living cells

    NARCIS (Netherlands)

    Snippe, M.; Borst, J.W.; Goldbach, R.W.; Kormelink, R.J.M.

    2005-01-01

    Fluorescence resonance energy transfer (FRET) and fluorescence lifetime imaging microscopy (FLIM) were employed to study homotypic protein¿protein interactions in living cells. To this end, the nucleocapsid (N) protein of tomato spotted wilt virus (TSWV) was expressed as a fusion protein with either

  13. Transient expression of Human papillomavirus type 16 L2 epitope fused to N- and C-terminus of coat protein of Potato virus X in plants

    Czech Academy of Sciences Publication Activity Database

    Čeřovská, Noemi; Hoffmeisterová, Hana; Moravec, Tomáš; Plchová, Helena; Folwarczna, Jitka; Synková, Helena; Ryšlavá, H.; Ludvíková, V.; Šmahel, M.

    2012-01-01

    Roč. 37, č. 1 (2012), s. 125-133 ISSN 0250-5991 R&D Projects: GA ČR GA521/06/0973; GA ČR GA521/09/1525 Institutional research plan: CEZ:AV0Z50380511 Keywords : Human papillomavirus (HPV-16) * L2-and E7-derived epitopes * transient expression Subject RIV: FD - Oncology ; Hematology Impact factor: 1.759, year: 2012

  14. Efficient expression of Human papillomavirus 16 E7 oncoprotein fused to C-terminus of Tobacco mosaic virus (TMV) coat protein using molecular chaperones in Escherichia coli

    Czech Academy of Sciences Publication Activity Database

    Folwarczna, Jitka; Moravec, Tomáš; Plchová, Helena; Hoffmeisterová, Hana; Čeřovská, Noemi

    2012-01-01

    Roč. 85, č. 1 (2012), s. 152-157 ISSN 1046-5928 R&D Projects: GA ČR GA521/09/1525; GA ČR GAP501/12/1761 Institutional research plan: CEZ:AV0Z50380511 Keywords : Bacterial expression * Human papillomavirus * E7 oncoprotein Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.429, year: 2012

  15. Functional characterization of protein domains common to animal viruses and mouse.

    Science.gov (United States)

    Kinjo, Akira R; Kumagai, Yutaro; Dinh, Huy; Takeuchi, Osamu; Standley, Daron M

    2011-11-30

    Many viruses contain genes that originate from their hosts. Some of these acquired genes give viruses the ability to interfere with host immune responses by various mechanisms. Genes of host origin that appear commonly in viruses code for proteins that span a wide range of functions, from kinases and phosphotases, to cytokines and their receptors, to ubiquitin ligases and proteases. While many important cases of such lateral gene transfer in viruses have been documented, there has yet to be a genome-wide survey of viral-encoded genes acquired from animal hosts. Here we carry out such a survey in order to gain insight into the host immune system. We made the results available in the form of a web-based tool that allows viral-centered or host-centered queries to be performed (http://imm.ifrec.osaka-u.ac.jp/musvirus/). We examine the relationship between acquired genes and immune function, and compare host-virus homology with gene expression data in stimulated dendritic cells and T-cells. We found that genes whose expression changes significantly during the innate antiviral immune response had more homologs in animal virus than genes whose expression did not change or genes involved in the adaptive immune response. Statistics gathered from the MusVirus database support earlier reports of gene transfer from host to virus and indicate that viruses are more likely to acquire genes involved in innate antiviral immune responses than those involved in acquired immune responses.

  16. Ceftriaxone protects against the neurotoxicity of human immunodeficiency virus proteins.

    Science.gov (United States)

    Rumbaugh, Jeffrey A; Li, Guanhan; Rothstein, Jeffrey; Nath, Avindra

    2007-04-01

    Human immunodeficiency virus (HIV) proteins Tat and gp120 have been implicated in the pathogenesis of HIV dementia by various mechanisms, including down-regulation of excitatory amino acid transporter-2 (EAAT2), which is responsible for inactivation of synaptic glutamate. Recent work indicates that beta-lactam antibiotics are potent stimulators of EAAT2 expression. The authors treated mixed human fetal neuronal cultures with recombinant gp120 or Tat, in the presence or absence of ceftriaxone, and determined neurotoxicity by measuring mitochondrial membrane potential and neuronal cell death. Ceftriaxone produced dose-dependent attenuation of the neurotoxicity and neuronal cell death caused by both viral proteins. This study demonstrates that this class of drugs may have therapeutic efficacy in HIV dementia.

  17. Pericentriolar Targeting of the Mouse Mammary Tumor Virus GAG Protein.

    Directory of Open Access Journals (Sweden)

    Guangzhi Zhang

    Full Text Available The Gag protein of the mouse mammary tumor virus (MMTV is the chief determinant of subcellular targeting. Electron microscopy studies show that MMTV Gag forms capsids within the cytoplasm and assembles as immature particles with MMTV RNA and the Y box binding protein-1, required for centrosome maturation. Other betaretroviruses, such as Mason-Pfizer monkey retrovirus (M-PMV, assemble adjacent to the pericentriolar region because of a cytoplasmic targeting and retention signal in the Matrix protein. Previous studies suggest that the MMTV Matrix protein may also harbor a similar cytoplasmic targeting and retention signal. Herein, we show that a substantial fraction of MMTV Gag localizes to the pericentriolar region. This was observed in HEK293T, HeLa human cell lines and the mouse derived NMuMG mammary gland cells. Moreover, MMTV capsids were observed adjacent to centrioles when expressed from plasmids encoding either MMTV Gag alone, Gag-Pro-Pol or full-length virus. We found that the cytoplasmic targeting and retention signal in the MMTV Matrix protein was sufficient for pericentriolar targeting, whereas mutation of the glutamine to alanine at position 56 (D56/A resulted in plasma membrane localization, similar to previous observations from mutational studies of M-PMV Gag. Furthermore, transmission electron microscopy studies showed that MMTV capsids accumulate around centrioles suggesting that, similar to M-PMV, the pericentriolar region may be a site for MMTV assembly. Together, the data imply that MMTV Gag targets the pericentriolar region as a result of the MMTV cytoplasmic targeting and retention signal, possibly aided by the Y box protein-1 required for the assembly of centrosomal microtubules.

  18. The Tat protein of human immunodeficiency virus-1 enhances hepatitis C virus replication through interferon gamma-inducible protein-10

    Directory of Open Access Journals (Sweden)

    Qu Jing

    2012-04-01

    Full Text Available Abstract Background Co-infection with human immunodeficiency virus-1 (HIV-1 and hepatitis C virus (HCV is associated with faster progression of liver disease and an increase in HCV persistence. However, the mechanism by which HIV-1 accelerates the progression of HCV liver disease remains unknown. Results HIV-1/HCV co-infection is associated with increased expression of interferon gamma-induced protein-10 (IP-10 mRNA in peripheral blood mononuclear cells (PBMCs. HCV RNA levels were higher in PBMCs of patients with HIV-1/HCV co-infection than in patients with HCV mono-infection. HIV-1 Tat and IP-10 activated HCV replication in a time-dependent manner, and HIV-1 Tat induced IP-10 production. In addition, the effect of HIV-1 Tat on HCV replication was blocked by anti-IP-10 monoclonal antibody, demonstrating that the effect of HIV-1 Tat on HCV replication depends on IP-10. Taken together, these results suggest that HIV-1 Tat protein activates HCV replication by upregulating IP-10 production. Conclusions HIV-1/HCV co-infection is associated with increased expression of IP-10 mRNA and replication of HCV RNA. Furthermore, both HIV-1 Tat and IP-10 activate HCV replication. HIV-1 Tat activates HCV replication by upregulating IP-10 production. These results expand our understanding of HIV-1 in HCV replication and the mechanism involved in the regulation of HCV replication mediated by HIV-1 during co-infection.

  19. Virus-like particles that display Zika virus envelope protein domain III induce potent neutralizing immune responses in mice.

    Science.gov (United States)

    Yang, Ming; Lai, Huafang; Sun, Haiyan; Chen, Qiang

    2017-08-09

    Several Zika virus (ZIKV) vaccine candidates have recently been described which use inactivated whole virus, DNA or RNA that express the virus' Envelope (E) glycoprotein as the antigen. These were successful in stimulating production of virus-targeted antibodies that protected animals against ZIKV challenges, but their use potentially will predispose vaccinated individuals to infection by the related Dengue virus (DENV). We have devised a virus like particle (VLP) carrier based on the hepatitis B core antigen (HBcAg) that displays the ZIKV E protein domain III (zDIII), and shown that it can be produced quickly and easily purified in large quantities from Nicotiana benthamiana plants. HBcAg-zDIII VLPs are shown to be highly immunogenic, as two doses elicited potent humoral and cellular responses in mice that exceed the threshold correlated with protective immunity against multiple strains of Zika virus. Notably, HBcAg-zDIII VLPs-elicited antibodies did not enhance the infection of DENV in Fc gamma receptor-expressing cells, offsetting the concern of ZIKV vaccines inducing cross-reactive antibodies and sensitizing people to subsequent DENV infection. Thus, our zDIII-based vaccine offers improved safety and lower cost production than other current alternatives, with equivalent effectiveness.

  20. Tagging of the vaccinia virus protein F13 with mCherry causes aberrant virion morphogenesis.

    Science.gov (United States)

    Carpentier, David C J; Hollinshead, Michael S; Ewles, Helen A; Lee, Stacey-Ann; Smith, Geoffrey L

    2017-09-20

    Vaccinia virus produces two distinct infectious virions; the single-enveloped intracellular mature virus (IMV), which remains in the cell until cell lysis, and the double-enveloped extracellular enveloped virus (EEV), which mediates virus spread. The latter is derived from a triple-enveloped intracellular enveloped virus (IEV) precursor, which is transported to the cell periphery by the kinesin-1 motor complex. This transport involves the viral protein A36 as well as F12 and E2. A36 is an integral membrane protein associated with the outer virus envelope and is the only known direct link between virion and kinesin-1 complex. Yet in the absence of A36 virion egress still occurs on microtubules, albeit at reduced efficiency. In this paper double-fluorescent labelling of the capsid protein A5 and outer-envelope protein F13 was exploited to visualize IEV transport by live-cell imaging in the absence of either A36 or F12. During the generation of recombinant viruses expressing both A5-GFP and F13-mCherry a plaque size defect was identified that was particularly severe in viruses lacking A36. Electron microscopy showed that this phenotype was caused by abnormal wrapping of IMV to form IEV, and this resulted in reduced virus egress to the cell surface. The aberrant wrapping phenotype suggests that the fluorescent fusion protein interferes with an interaction of F13 with the IMV surface that is required for tight association between IMVs and wrapping membranes. The severity of this defect suggests that these viruses are imperfect tools for characterizing virus egress.

  1. Development and application of hepatitis C reporter viruses with genotype 1 to 7 core-nonstructural protein 2 (NS2) expressing fluorescent proteins or luciferase in modified JFH1 NS5A

    DEFF Research Database (Denmark)

    Gottwein, Judith M; Jensen, Tanja B; Mathiesen, Christian K

    2011-01-01

    of these reporter viruses for high-throughput fluorescence- and luminescence-based studies of HCV-receptor interactions and serum-neutralizing antibodies was demonstrated. Finally, using RLuc viruses, we showed that the genotype-specific core-NS2 sequence did not influence the response to alfa-2b interferon (IFN-alfa...

  2. Alfalfa mosaic virus replicase proteins, P1 and P2, localize to the tonoplast in the presence of virus RNA

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, Amr [Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907 (United States); Present address: Genomics Facility, Agricultural Genetic Engineering Research Institute, Agricultural Research Center, Giza 12619 (Egypt); Hutchens, Heather M. [Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907 (United States); Howard Berg, R. [Integrated Microscopy Facility, Donald Danforth Plant Science Center, Saint Louis, MO 63132 (United States); Sue Loesch-Fries, L., E-mail: loeschfr@purdue.edu [Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907 (United States)

    2012-11-25

    To identify the virus components important for assembly of the Alfalfa mosaic virus replicase complex, we used live cell imaging of Arabidopsis thaliana protoplasts that expressed various virus cDNAs encoding native and GFP-fusion proteins of P1 and P2 replicase proteins and full-length virus RNAs. Expression of P1-GFP alone resulted in fluorescent vesicle-like bodies in the cytoplasm that colocalized with FM4-64, an endocytic marker, and RFP-AtVSR2, RabF2a/Rha1-mCherry, and RabF2b/Ara7-mCherry, all of which localize to multivesicular bodies (MVBs), which are also called prevacuolar compartments, that mediate traffic to the lytic vacuole. GFP-P2 was driven from the cytosol to MVBs when expressed with P1 indicating that P1 recruited GFP-P2. P1-GFP localized on the tonoplast, which surrounds the vacuole, in the presence of infectious virus RNA, replication competent RNA2, or P2 and replication competent RNA1 or RNA3. This suggests that a functional replication complex containing P1, P2, and a full-length AMV RNA assembles on MVBs to traffic to the tonoplast.

  3. Predictable tuning of protein expression in bacteria

    DEFF Research Database (Denmark)

    Bonde, Mads; Pedersen, Margit; Klausen, Michael Schantz

    2016-01-01

    We comprehensively assessed the contribution of the Shine-Dalgarno sequence to protein expression and used the data to develop EMOPEC (Empirical Model and Oligos for Protein Expression Changes; http://emopec.biosustain.dtu.dk). EMOPEC is a free tool that makes it possible to modulate the expressi...

  4. The V Protein of Mumps Virus Plays a Critical Role in Pathogenesis

    Science.gov (United States)

    Xu, Pei; Luthra, Priya; Li, Zhuo; Fuentes, Sandra; D'Andrea, James Alexander; Wu, Jianguo; Rubin, Steven; Rota, Paul A.

    2012-01-01

    Mumps virus (MuV) causes an acute infection in humans characterized by a wide array of symptoms ranging from relatively mild manifestations, such as parotitis, to more-severe complications, such as meningitis and encephalitis. Widespread mumps vaccination has reduced mumps incidence dramatically; however, outbreaks still occur in vaccinated populations. The V protein of MuV, when expressed in cell culture, blocks interferon (IFN) expression and signaling and interleukin-6 (IL-6) signaling. In this work, we generated a recombinant MuV incapable of expressing the V protein (rMuVΔV). The rescued MuV was derived from a clinical wild-type isolate from a recent outbreak in the United States (MuVIowa/US/06, G genotype). Analysis of the virus confirmed the roles of V protein in blocking IFN expression and signaling and IL-6 signaling. We also found that the rMuVIowa/US/06ΔV virus induced high levels of IL-6 expression in vitro, suggesting that V plays a role in reducing IL-6 expression. In vivo, the rMuVIowa/US/06ΔV virus was highly attenuated, indicating that the V protein plays an essential role in viral virulence. PMID:22090137

  5. The V protein of mumps virus plays a critical role in pathogenesis.

    Science.gov (United States)

    Xu, Pei; Luthra, Priya; Li, Zhuo; Fuentes, Sandra; D'Andrea, James Alexander; Wu, Jianguo; Rubin, Steven; Rota, Paul A; He, Biao

    2012-02-01

    Mumps virus (MuV) causes an acute infection in humans characterized by a wide array of symptoms ranging from relatively mild manifestations, such as parotitis, to more-severe complications, such as meningitis and encephalitis. Widespread mumps vaccination has reduced mumps incidence dramatically; however, outbreaks still occur in vaccinated populations. The V protein of MuV, when expressed in cell culture, blocks interferon (IFN) expression and signaling and interleukin-6 (IL-6) signaling. In this work, we generated a recombinant MuV incapable of expressing the V protein (rMuVΔV). The rescued MuV was derived from a clinical wild-type isolate from a recent outbreak in the United States (MuV(Iowa/US/06), G genotype). Analysis of the virus confirmed the roles of V protein in blocking IFN expression and signaling and IL-6 signaling. We also found that the rMuV(Iowa/US/06)ΔV virus induced high levels of IL-6 expression in vitro, suggesting that V plays a role in reducing IL-6 expression. In vivo, the rMuV(Iowa/US/06)ΔV virus was highly attenuated, indicating that the V protein plays an essential role in viral virulence.

  6. Immunohistochemical expression of latent membrane protein 1 ...

    African Journals Online (AJOL)

    Background: Nasopharyngeal carcinoma (NPC) is a malignant epithelial tumor intimately associated with Epstein-Barr virus (EBV). NPC is a characteristic tumor displaying epidemiological, genetic and regional distribution properties that makes it unique by its natural behavior. Objectives: To assess the expression pattern ...

  7. [Construction and expression of recombinant adeno-associated virus expressing brain-derived neurotrophic factor].

    Science.gov (United States)

    Li, Huiming; Qiu, Wei; Wang, Feng; Wei, Fang; Chen, Xiafang; Wu, Xiaobing; Huang, Qian

    2008-02-01

    A fusion gene called Ig-BDNF, in which brain-derived neurotrophic factor cDNA fused to the 3' end of signal peptide of Ig coding sequence, was constructed by PCR, digested and subcloned into shuttle plasmid pSNAV to obtain a recombinant plasmid pSNAV-Ig-BDNF. Then the plasmid encoding fusion protein was transfected into 293 cell lines and the stably transfected clones were selected with neomycin. AAV1 containing Ig-BDNF fusion gene vectors were obtained by super-infection by Herpes virus. The resultant adeno-associated virus vectors AAV-Ig-BDNF were confirmed by PCR, Western blotting and a sandwich enzyme-linked immunosorbent assay (ELISA) after infection of 293 cell lines. The results indicated that AAV-Ig-BDNF contained the target gene, and infected cells and produced the fusion protein into the supernatant. The content of BDNF in medium per 5x104 cells over a 24 h incubation period reached 1000 pg/mL. With the help of non-replicative adenovirus during AAV-Ig-BDNF infection, the expression of BDNF increased 7-8 fold, and the enhancement of BDNF gene expression was observed in a concentration-dependent manner. These results suggested that a functional AAV-Ig-BDNF was successfully constructed and it offers basis for further study for gene therapy of neural degeneration diseases.

  8. Bluetongue Virus NS4 Protein Is an Interferon Antagonist and a Determinant of Virus Virulence.

    Science.gov (United States)

    Ratinier, Maxime; Shaw, Andrew E; Barry, Gerald; Gu, Quan; Di Gialleonardo, Luigina; Janowicz, Anna; Varela, Mariana; Randall, Richard E; Caporale, Marco; Palmarini, Massimo

    2016-06-01

    Bluetongue virus (BTV) is the causative agent of bluetongue, a major infectious disease of ruminants with serious consequences to both animal health and the economy. The clinical outcome of BTV infection is highly variable and dependent on a variety of factors related to both the virus and the host. In this study, we show that the BTV nonstructural protein NS4 favors viral replication in sheep, the animal species most affected by bluetongue. In addition, NS4 confers a replication advantage on the virus in interferon (IFN)-competent primary sheep endothelial cells and immortalized cell lines. We determined that in cells infected with an NS4 deletion mutant (BTV8ΔNS4), there is increased synthesis of type I IFN compared to cells infected with wild-type BTV-8. In addition, using RNA sequencing (RNA-seq), we show that NS4 modulates the host IFN response and downregulates mRNA levels of type I IFN and interferon-stimulated genes. Moreover, using reporter assays and protein synthesis assays, we show that NS4 downregulates the activities of a variety of promoters, such as the cytomegalovirus immediate-early promoter, the IFN-β promoter, and a promoter containing interferon-stimulated response elements (ISRE). We also show that the NS4 inhibitory activity on gene expression is related to its nucleolar localization. Furthermore, NS4 does not affect mRNA splicing or cellular translation. The data obtained in this study strongly suggest that BTV NS4 is an IFN antagonist and a key determinant of viral virulence. Bluetongue is one of the main infectious diseases of ruminants and is caused by bluetongue virus (BTV), an arthropod-borne virus transmitted from infected to susceptible animals by Culicoides biting midges. Bluetongue has a variable clinical outcome that can be related to both virus and host factors. It is therefore critical to understand the interplay between BTV and the host immune responses. In this study, we show that a nonstructural protein of BTV (NS4) is

  9. The Heterologous Expression of the p22 RNA Silencing Suppressor of the Crinivirus Tomato Chlorosis Virus from Tobacco Rattle Virus and Potato Virus X Enhances Disease Severity but Does Not Complement Suppressor-Defective Mutant Viruses.

    Science.gov (United States)

    Landeo-Ríos, Yazmín; Navas-Castillo, Jesús; Moriones, Enrique; Cañizares, M. Carmen

    2017-11-24

    To counteract host antiviral RNA silencing, plant viruses express suppressor proteins that function as pathogenicity enhancers. The genome of the Tomato chlorosis virus (ToCV) (genus Crinivirus, family Closteroviridae) encodes an RNA silencing suppressor, the protein p22, that has been described as having one of the longest lasting local suppressor activities when assayed in Nicotiana benthamiana. Since suppression of RNA silencing and the ability to enhance disease severity are closely associated, we analyzed the effect of expressing p22 in heterologous viral contexts. Thus, we studied the effect of the expression of ToCV p22 from viral vectors Tobacco rattle virus (TRV) and Potato virus X (PVX), and from attenuated suppressor mutants in N. benthamiana plants. Our results show that although an exacerbation of disease symptoms leading to plant death was observed in the heterologous expression of ToCV p22 from both viruses, only in the case of TRV did increased viral accumulation occur. The heterologous expression of ToCV p22 could not complement suppressor-defective mutant viruses.

  10. The Heterologous Expression of the p22 RNA Silencing Suppressor of the Crinivirus Tomato Chlorosis Virus from Tobacco Rattle Virus and Potato Virus X Enhances Disease Severity but Does Not Complement Suppressor-Defective Mutant Viruses

    Directory of Open Access Journals (Sweden)

    Yazmín Landeo-Ríos

    2017-11-01

    Full Text Available To counteract host antiviral RNA silencing, plant viruses express suppressor proteins that function as pathogenicity enhancers. The genome of the Tomato chlorosis virus (ToCV (genus Crinivirus, family Closteroviridae encodes an RNA silencing suppressor, the protein p22, that has been described as having one of the longest lasting local suppressor activities when assayed in Nicotiana benthamiana. Since suppression of RNA silencing and the ability to enhance disease severity are closely associated, we analyzed the effect of expressing p22 in heterologous viral contexts. Thus, we studied the effect of the expression of ToCV p22 from viral vectors Tobacco rattle virus (TRV and Potato virus X (PVX, and from attenuated suppressor mutants in N. benthamiana plants. Our results show that although an exacerbation of disease symptoms leading to plant death was observed in the heterologous expression of ToCV p22 from both viruses, only in the case of TRV did increased viral accumulation occur. The heterologous expression of ToCV p22 could not complement suppressor-defective mutant viruses.

  11. Sequences within the VP6 molecule of bluetongue virus that determine cytoplasmic and nuclear targeting of the protein.

    OpenAIRE

    Yi, C K; Bansal, O B; Hong, M L; Chatterjee, S.; Roy, P

    1996-01-01

    Genome segment 9 of bluetongue virus serotype 10 encodes the minor protein VP6. The protein is abundant with basic residues particularly in two regions of the carboxy half of the molecule. A series of amino- and carboxy-terminal deletion mutants was expressed in mammalian cells by using a vaccinia virus T7 polymerase-driven transient expression system, and the intracellular fate of the products was monitored by both immunofluorescence staining and cell fractionation techniques. Data obtained ...

  12. Virus-Like Particles That Can Deliver Proteins and RNA | NCI Technology Transfer Center | TTC

    Science.gov (United States)

    The present invention describes novel virus-like particles (VLPs) that are capable of binding to and replicating within a target mammalian cell, including human cells. The claimed VLPs are safer than viral delivery because they are incapable of re-infecting target cells. The National Cancer Institute's Protein Expression Laboratory seeks parties interested in licensing the novel delivery of RNA to mammalian cells using virus-like particles.

  13. Cell-based analysis of Chikungunya virus membrane fusion using baculovirus-expression vectors.

    Science.gov (United States)

    Kuo, Szu-Cheng; Chen, Ying-Ju; Wang, Yu-Ming; Kuo, Ming-Der; Jinn, Tzyy-Rong; Chen, Wen-Shuo; Chang, Yen-Chung; Tung, Kuo-Lun; Wu, Tzong-Yuan; Lo, Szecheng J

    2011-08-01

    Chikungunya virus infection has emerged in many countries over the past decade. There are no effective drugs for controlling the disease. To develop cell-based system for screening anti-virus drugs, a bi-cistronic baculovirus expression system was utilized to co-express viral structural proteins C (capsid), E2 and E1 and the enhanced green fluorescence protein (EGFP) in Spodoptera frugiperda insect cells (Sf21). The EGFP-positive Sf21 cells fused with each other and with uninfected cells to form a syncytium, allowing characterization of cholesterol and low pH requirements for syncytium formation. Western blot analysis showed three structural proteins were expressed in baculovirus infected cells. The structural proteins of Chikungunya virus that is required for cell fusion was determined with various recombinant baculoviruses bearing different lengths of the viral structural protein genes. Protein E1 was required for cell fusion and indicating that Chikungunya viral membrane fusion was a class II membrane fusion. It was also demonstrated that the heterologous expression of alphavirus monomeric E1 can induce insect cell fusions. Furthermore, this cell-based system provides a model for studying class II viral membrane fusion. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Matrix proteins of Nipah and Hendra viruses interact with beta subunits of AP-3 complexes.

    Science.gov (United States)

    Sun, Weina; McCrory, Thomas S; Khaw, Wei Young; Petzing, Stephanie; Myers, Terrell; Schmitt, Anthony P

    2014-11-01

    Paramyxoviruses and other negative-strand RNA viruses encode matrix proteins that coordinate the virus assembly process. The matrix proteins link the viral glycoproteins and the viral ribonucleoproteins at virus assembly sites and often recruit host machinery that facilitates the budding process. Using a co-affinity purification strategy, we have identified the beta subunit of the AP-3 adapter protein complex, AP3B1, as a binding partner for the M proteins of the zoonotic paramyxoviruses Nipah virus and Hendra virus. Binding function was localized to the serine-rich and acidic Hinge domain of AP3B1, and a 29-amino-acid Hinge-derived polypeptide was sufficient for M protein binding in coimmunoprecipitation assays. Virus-like particle (VLP) production assays were used to assess the relationship between AP3B1 binding and M protein function. We found that for both Nipah virus and Hendra virus, M protein expression in the absence of any other viral proteins led to the efficient production of VLPs in transfected cells, and this VLP production was potently inhibited upon overexpression of short M-binding polypeptides derived from the Hinge region of AP3B1. Both human and bat (Pteropus alecto) AP3B1-derived polypeptides were highly effective at inhibiting the production of VLPs. VLP production was also impaired through small interfering RNA (siRNA)-mediated depletion of AP3B1 from cells. These findings suggest that AP-3-directed trafficking processes are important for henipavirus particle production and identify a new host protein-virus protein binding interface that could become a useful target in future efforts to develop small molecule inhibitors to combat paramyxoviral infections. Henipaviruses cause deadly infections in humans, with a mortality rate of about 40%. Hendra virus outbreaks in Australia, all involving horses and some involving transmission to humans, have been a continuing problem. Nipah virus caused a large outbreak in Malaysia in 1998, killing 109 people

  15. Endogenous expression of proteases in colon cancer cells facilitate influenza A viruses mediated oncolysis.

    Science.gov (United States)

    Sturlan, Sanda; Stremitzer, Stefan; Bauman, Suzann; Sachet, Monika; Wolschek, Markus; Ruthsatz, Tanja; Egorov, Andrej; Bergmann, Michael

    2010-09-15

    Previously we have developed a prototype for conditionally replicating oncolytic influenza A virus which is based on deletions in the non-structural (NS1) protein. Multi-cycle replication of influenza A virus in malignant tissue is critically dependent on a protease which cleaves the viral entry protein. Here we demonstrate that the malignant colon cancer cell lines Caco-2, HT-29 and SW-620 can endogenously provide a virus-activating protease, which allows lytic multi-cycle replication of NS1 deletion viruses in those cancer cells in vitro. The oncolytic potency of an influenza NS1 deletion virus (NS1-80) was further tested in SCID mice bearing HT-29 derived tumors. The intra-tumoral injection of live, but not of heat inactivated NS1-80 virus significantly inhibited progression of established tumors. We conclude that a selected set of human cancer expressing virus activating- proteases will be a preferred target for oncolytic tumor therapy using influenza A virus mutants.

  16. Proteomic analysis of membrane proteins of vero cells: exploration of potential proteins responsible for virus entry.

    Science.gov (United States)

    Guo, Donghua; Zhu, Qinghe; Zhang, Hong; Sun, Dongbo

    2014-01-01

    Vero cells are highly susceptible to many viruses in humans and animals, and its membrane proteins (MPs) are responsible for virus entry. In our study, the MP proteome of the Vero cells was investigated using a shotgun LC-MS/MS approach. Six hundred twenty-seven proteins, including a total of 1839 peptides, were identified in MP samples of the Vero cells. In 627 proteins, 307 proteins (48.96%) were annotated in terms of biological process of gene ontology (GO) categories; 356 proteins (56.78%) were annotated in terms of molecular function of GO categories; 414 proteins (66.03%) were annotated in terms of cellular components of GO categories. Of 627 identified proteins, seventeen proteins had been revealed to be virus receptor proteins. The resulting protein lists and highlighted proteins may provide valuable information to increase understanding of virus infection of Vero cells.

  17. [Detection of human papilloma virus (HPV) in liquid-based cervical samples. Correlation with protein p16INK4a expression].

    Science.gov (United States)

    Toro de Méndez, Morelva; Ferrández Izquierdo, Antonio

    2011-03-01

    The liquid-based cervical cytology improves the quality of the sample and the residual sample could be used efficiently to carry out complementary tests, such as the detection of HPV DNA and the immunocytochemical biomarkers study. The purpose of this study was to correlate the presence of HPV and immunoexpression of p16INK4a in liquid-based cervical samples to examine the utility of these new tools in the detection of cervical cancer. The included patients (n = 67) presented an abnormal cytology or previous cervical pathology. The HPV detection and genotyping were carried out with PCR-SPF10/LiPA (INNOLiPA Extra Amp) and for p16INK4a immunodetection was used antibody clone E6H4. The conventional cytology provided the same cytologic interpretations that those of liquid-based cytology. The overall HPV prevalence was 43.3% (29/67). HPV16 was the most frequent viral type (31.03%) and 48.3% of the cases were infected with multiple HPV types. p16INK4a immunoexpression was observed in 35.8% of liquid-based cytological samples and this was significantly (p HPV presence. These results support the evidence that the implementation of new technologies in the daily routine of the laboratory, contribute significantly in the early detection of cervical cancer and provide important data to help in the patient's efficient management. The combined use of HPV detection and p16INK4a expression could be used for evaluation of patients with more risk to develop significant cervical lesions.

  18. Attenuated Human Parainfluenza Virus Type 1 Expressing Ebola Virus Glycoprotein GP Administered Intranasally Is Immunogenic in African Green Monkeys.

    Science.gov (United States)

    Lingemann, Matthias; Liu, Xueqiao; Surman, Sonja; Liang, Bo; Herbert, Richard; Hackenberg, Ashley D; Buchholz, Ursula J; Collins, Peter L; Munir, Shirin

    2017-05-15

    The recent 2014-2016 Ebola virus (EBOV) outbreak prompted increased efforts to develop vaccines against EBOV disease. We describe the development and preclinical evaluation of an attenuated recombinant human parainfluenza virus type 1 (rHPIV1) expressing the membrane-anchored form of EBOV glycoprotein GP, as an intranasal (i.n.) EBOV vaccine. GP was codon optimized and expressed either as a full-length protein or as an engineered chimeric form in which its transmembrane and cytoplasmic tail (TMCT) domains were replaced with those of the HPIV1 F protein in an effort to enhance packaging into the vector particle and immunogenicity. GP was inserted either preceding the N gene (pre-N) or between the N and P genes (N-P) of rHPIV1 bearing a stabilized attenuating mutation in the P/C gene (CΔ170). The constructs grew to high titers and efficiently and stably expressed GP. Viruses were attenuated, replicating at low titers over several days, in the respiratory tract of African green monkeys (AGMs). Two doses of candidates expressing GP from the pre-N position elicited higher GP neutralizing serum antibody titers than the N-P viruses, and unmodified GP induced higher levels than its TMCT counterpart. Unmodified EBOV GP was packaged into the HPIV1 particle, and the TMCT modification did not increase packaging or immunogenicity but rather reduced the stability of GP expression during in vivo replication. In conclusion, we identified an attenuated and immunogenic i.n. vaccine candidate expressing GP from the pre-N position. It is expected to be well tolerated in humans and is available for clinical evaluation.IMPORTANCE EBOV hemorrhagic fever is one of the most lethal viral infections and lacks a licensed vaccine. Contact of fluids from infected individuals, including droplets or aerosols, with mucosal surfaces is an important route of EBOV spread during a natural outbreak, and aerosols also might be exploited for intentional virus spread. Therefore, vaccines that protect

  19. Identification of Epstein-Barr Virus Replication Proteins in Burkitt’s Lymphoma Cells

    Directory of Open Access Journals (Sweden)

    Chris Traylen

    2015-10-01

    Full Text Available The working model to describe the mechanisms used to replicate the cancer-associated virus Epstein-Barr virus (EBV is partly derived from comparisons with other members of the Herpes virus family. Many genes within the EBV genome are homologous across the herpes virus family. Published transcriptome data for the EBV genome during its lytic replication cycle show extensive transcription, but the identification of the proteins is limited. We have taken a global proteomics approach to identify viral proteins that are expressed during the EBV lytic replication cycle. We combined an enrichment method to isolate cells undergoing EBV lytic replication with SILAC-labeling coupled to mass-spectrometry and identified viral and host proteins expressed during the OPEN ACCESS Pathogens 2015, 4 740 EBV lytic replication cycle. Amongst the most frequently identified viral proteins are two components of the DNA replication machinery, the single strand DNA binding protein BALF2, DNA polymerase accessory protein BMRF1 and both subunits of the viral ribonucleoside-diphosphate reductase enzyme (BORF2 and BaRF1. An additional 42 EBV lytic cycle proteins were also detected. This provides proteomic identification for many EBV lytic replication cycle proteins and also identifies post-translational modifications.

  20. Effects of poliovirus 2A(pro) on vaccinia virus gene expression.

    Science.gov (United States)

    Feduchi, E; Aldabe, R; Novoa, I; Carrasco, L

    1995-12-15

    The effects of transient expression of poliovirus 2A(pro) on p220 cleavage in COS cells have been analyzed. When 2A(pro) was cloned in plasmid pTM1 and transiently expressed in COS cells, efficient cleavage of p220 occurred after infection of these cells with a recombinant vaccinia virus bearing phage T7 RNA polymerase. High numbers of COS cells were transfected with pTM1-2A, as judged by p220 cleavage, thereby allowing an analysis of the effects of poliovirus 2A(pro) on vaccinia virus gene expression. A 40-50% cleavage of p220 by transfected poliovirus 2A(pro) was observed ten hours post infection and cleavage was almost complete (80-90%) 20-25 hours post infection with vaccinia virus. Profound inhibition of vaccinia virus protein synthesis was detectable ten hours post infection and was maximal 20-25 hours post infection. This inhibition resulted from neither a blockade of transcription of vaccinia virus nor a lack of translatability of the mRNAs present in cells that synthesize poliovirus 2A(pro). Addition of ara-C inhibited the replication of vaccinia virus and allowed the continued synthesis of cellular proteins. Under these conditions, 2A(pro) is expressed and blocks cellular translation. Finally, p220 cleavage by 2A(pro) did not inhibit the translation of a mRNA encoding poliovirus protein 2C, as directed by the 5' leader sequences of encephalomiocarditis virus. Therefore, these findings show a correlation between p220 cleavage and inhibition of translation from newly made mRNAs. Our results are discussed in the light of present knowledge of p220 function, and new approaches are considered that might provide further insights into the function(s) of initiation factor eIF-4F.

  1. Adeno-associated virus rep protein synthesis during productive infection

    Energy Technology Data Exchange (ETDEWEB)

    Redemann, B.E.; Mendelson, E.; Carter, B.J.

    1989-02-01

    Adeno-associated virus (AAV) Rep proteins mediate viral DNA replication and can regulate expression from AAV genes. The authors studied the kinetics of synthesis of the four Rep proteins, Rep78, Rep68, Rep52, and Rep40, during infection of human 293 or KB cells with AAV and helper adenovirus by in vivo labeling with (/sup 35/S)methionine, immunoprecipitation, and immunoblotting analyses. Rep78 and Rep52 were readily detected concomitantly with detection of viral monomer duplex DNA replicating about 10 to 12 h after infection, and Rep68 and Rep40 were detected 2 h later. Rep78 and Rep52 were more abundant than Rep68 and Rep40 owing to a higher synthesis rate throughout the infectious cycle. In some experiments, very low levels of Rep78 could be detected as early as 4 h after infection. The synthesis rates of Rep proteins were maximal between 14 and 24 h and then decreased later after infection. Isotopic pulse-chase experiments showed that each of the Rep proteins was synthesized independently and was stable for at least 15 h. A slower-migrating, modified form of Rep78 was identified late after infection. AAV capsid protein synthesis was detected at 10 to 12 h after infection and also exhibited synthesis kinetics similar to those of the Rep proteins. AAV DNA replication showed at least two clearly defined stages. Bulk duplex replicating DNA accumulation began around 10 to 12 h and reached a maximum level at about 20 h when Rep and capsid protein synthesis was maximal. Progeny single-stranded DNA accumulation began about 12 to 13 h, but most of this DNA accumulated after 24 h when Rep and capsid protein synthesis had decreased.

  2. The conundrum of a unique protein encoded by citrus tristeza virus that is dispensable for infection of most hosts yet shows characteristics of a viral movement protein.

    Science.gov (United States)

    Bak, Aurélie; Folimonova, Svetlana Y

    2015-11-01

    Citrus tristeza virus (CTV), one of the most economically important viruses, produces a unique protein, p33, which is encoded only in the genomes of isolates of CTV. Recently, we demonstrated that membrane association of the p33 protein confers virus ability to extend its host range. In this work we show that p33 shares characteristics of viral movement proteins. Upon expression in a host cell, the protein localizes to plasmodesmata and displays the ability to form extracellular tubules. Furthermore, p33 appears to traffic via the cellular secretory pathway and the actin network to plasmodesmata locations and is likely being recycled through the endocytic pathway. Finally, our study reveals that p33 colocalizes with a putative movement protein of CTV, the p6 protein. These results suggest a potential role of p33 as a noncanonical viral movement protein, which mediates virus translocation in the specific hosts. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Bovine parainfluenza virus type 3 accessory proteins that suppress beta interferon production.

    Science.gov (United States)

    Komatsu, Takayuki; Takeuchi, Kenji; Gotoh, Bin

    2007-07-01

    The paramyxovirus P gene encodes accessory proteins antagonistic to interferon (IFN). Viral proteins responsible for the IFN antagonism, however, are distinct among paramyxoviruses. Here we determine bovine parainfluenza virus type 3 (bPIV3) IFN antagonists that suppress IFN-beta production, and investigate the underlying molecular mechanism. Of bPIV3 P gene products, C and V proteins were found to suppress double-stranded RNA-stimulated IFN-beta production. The V protein of bPIV3 and Sendai virus in the same genus Respirovirus significantly inhibits double-stranded RNA-stimulated IFN-beta production and the IFN-beta promoter activation enhanced by overexpression of MDA5 but not RIG-I, and yet does not suppress IFN-beta production induced by TRIF, TBK1, and IKKi. The V protein of both viruses specifically binds to MDA5 but not RIG-I. These results suggest that the V protein targets MDA5 for blockage of the IFN-beta gene activation signal. On the other hand, both bPIV3 and Sendai virus C proteins modestly inhibited IFN-beta production irrespective of a species of the signaling molecules used as an inducer. Interestingly, reporter gene expression driven by various promoters was also suppressed by the C proteins irrespective of the promoter species. These results demonstrate that the target of the respirovirus C protein is undoubtedly different from that of the V protein.

  4. Molecular characterization and coat protein serology of watermelon leaf mottle virus (Potyvirus).

    Science.gov (United States)

    De Sa, P B; Hiebert, E; Purcifull, D E

    2000-01-01

    A cDNA library was generated from purified RNA of watermelon leaf mottle virus (WLMV) (Genus Potyvirus). Two overlapping clones totaling 2,316 nucleotides at the 3' terminus of the virus were identified by immunoscreening with coat protein antiserum. The sequence analyses of the clones indicated an open reading frame (ORF) of 2,050 nucleotides which encoded part of the replicase and the coat protein, a 243-nucleotide non-coding region (3'UTR), and 23 adenine residues of the poly (A) tail. The taxonomic status of WLMV was determined by comparisons of the sequence of the cloned coat protein gene and 3'UTR with potyvirus sequences obtained from GenBank. The nucleotide sequence identities of WLMV compared with 17 other potyviruses ranged from 55.6 to 63.5% for the coat protein, and from 37.2 to 48.3% for the 3'UTR. Phylogenetic analyses of the coat protein region and the 3'UTR indicated that WLMV did not cluster with other potyviruses in a clade with high bootstrap support. The coat protein gene was expressed in Escherichia coli and a polyclonal antiserum was prepared to the expressed coat protein. In immunodiffusion tests, WLMV was found to be serologically distinct from papaya ringspot virus type W, watermelon mosaic virus 2, zucchini yellow mosaic virus, and Moroccan watermelon mosaic virus. In Western blots and ELISA, serological cross-reactivity with other cucurbit potyviruses was observed. Serological and sequence comparisons indicated that watermelon leaf mottle virus is a distinct member of the Potyvirus genus.

  5. Protection against respiratory syncytial virus by inactivated influenza virus carrying a fusion protein neutralizing epitope in a chimeric hemagglutinin.

    Science.gov (United States)

    Lee, Yu-Na; Hwang, Hye Suk; Kim, Min-Chul; Lee, Young-Tae; Kim, Yu-Jin; Lee, F Eun-Hyung; Kang, Sang-Moo

    2016-04-01

    A desirable vaccine against respiratory syncytial virus (RSV) should induce neutralizing antibodies without eliciting abnormal T cell responses to avoid vaccine-enhanced pathology. In an approach to deliver RSV neutralizing epitopes without RSV-specific T cell antigens, we genetically engineered chimeric influenza virus expressing RSV F262-276 neutralizing epitopes in the globular head domain as a chimeric hemagglutinin (HA) protein. Immunization of mice with formalin-inactivated recombinant chimeric influenza/RSV F262-276 was able to induce RSV protective neutralizing antibodies and lower lung viral loads after challenge. Formalin-inactivated RSV immune mice showed high levels of pulmonary inflammatory cytokines, macrophages, IL-4-producing T cells, and extensive histopathology. However, RSV-specific T cell responses and enhancement of pulmonary histopathology were not observed after RSV infection of inactivated chimeric influenza/RSV F262-276. This study provides evidence that an inactivated vaccine platform of chimeric influenza/RSV virus can be developed into a safe RSV vaccine candidate without priming RSV-specific T cells and immunopathology. Respiratory syncytial virus (RSV) is a major cause of respiratory tract illness and morbidity in children. Hence, there is a need to develop an effective vaccine against this virus. In this article, the authors engineered chimeric influenza virus to express RSV neutralizing epitopes. The positive findings in in-vivo experiments provide a beginning for future clinical trials and perhaps eventual product realization. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Respiratory Syncytial Virus Attachment Glycoprotein Contribution to Infection Depends on the Specific Fusion Protein.

    Science.gov (United States)

    Meng, Jia; Hotard, Anne L; Currier, Michael G; Lee, Sujin; Stobart, Christopher C; Moore, Martin L

    2015-10-14

    Human respiratory syncytial virus (RSV) is an important pathogen causing acute lower respiratory tract disease in children. The RSV attachment glycoprotein (G) is not required for infection, as G-null RSV replicates efficiently in several cell lines. Our laboratory previously reported that the viral fusion (F) protein is a determinant of strain-dependent pathogenesis. Here, we hypothesized that virus dependence on G is determined by the strain specificity of F. We generated recombinant viruses expressing G and F, or null for G, from the laboratory A2 strain (Katushka RSV-A2GA2F [kRSV-A2GA2F] and kRSV-GstopA2F) or the clinical isolate A2001/2-20 (kRSV-2-20G2-20F and kRSV-Gstop2-20F). We quantified the virus cell binding, entry kinetics, infectivity, and growth kinetics of these four recombinant viruses in vitro. RSV expressing the 2-20 G protein exhibited the greatest binding activity. Compared to the parental viruses expressing G and F, removal of 2-20 G had more deleterious effects on binding, entry, infectivity, and growth than removal of A2 G. Overall, RSV expressing 2-20 F had a high dependence on G for binding, entry, and infection. RSV is the leading cause of childhood acute respiratory disease requiring hospitalization. As with other paramyxoviruses, two major RSV surface viral glycoproteins, the G attachment protein and the F fusion protein, mediate virus binding and subsequent membrane fusion, respectively. Previous work on the RSV A2 prototypical strain demonstrated that the G protein is functionally dispensable for in vitro replication. This is in contrast to other paramyxoviruses that require attachment protein function as a prerequisite for fusion. We reevaluated this requirement for RSV using G and F proteins from clinical isolate 2-20. Compared to the laboratory A2 strain, the G protein from 2-20 had greater contributions to virus binding, entry, infectivity, and in vitro growth kinetics. Thus, the clinical isolate 2-20 F protein function depended

  7. The Role of Severe Acute Respiratory Syndrome (SARS)-Coronavirus Accessory Proteins in Virus Pathogenesis

    Science.gov (United States)

    McBride, Ruth; Fielding, Burtram C.

    2012-01-01

    A respiratory disease caused by a novel coronavirus, termed the severe acute respiratory syndrome coronavirus (SARS-CoV), was first reported in China in late 2002. The subsequent efficient human-to-human transmission of this virus eventually affected more than 30 countries worldwide, resulting in a mortality rate of ~10% of infected individuals. The spread of the virus was ultimately controlled by isolation of infected individuals and there has been no infections reported since April 2004. However, the natural reservoir of the virus was never identified and it is not known if this virus will re-emerge and, therefore, research on this virus continues. The SARS-CoV genome is about 30 kb in length and is predicted to contain 14 functional open reading frames (ORFs). The genome encodes for proteins that are homologous to known coronavirus proteins, such as the replicase proteins (ORFs 1a and 1b) and the four major structural proteins: nucleocapsid (N), spike (S), membrane (M) and envelope (E). SARS-CoV also encodes for eight unique proteins, called accessory proteins, with no known homologues. This review will summarize the current knowledge on SARS-CoV accessory proteins and will include: (i) expression and processing; (ii) the effects on cellular processes; and (iii) functional studies. PMID:23202509

  8. TRPM4 protein expression in prostate cancer

    DEFF Research Database (Denmark)

    Berg, Kasper Drimer; Soldini, Davide; Jung, Maria

    2016-01-01

    BACKGROUND: Transient receptor potential cation channel, subfamily M, member 4 (TRPM4) messenger RNA (mRNA) has been shown to be upregulated in prostate cancer (PCa) and might be a new promising tissue biomarker. We evaluated TRPM4 protein expression and correlated the expression level.......79-2.62; p = 0.01-0.03 for the two observers) when compared to patients with a lower staining intensity. CONCLUSIONS: TRPM4 protein expression is widely expressed in benign and cancerous prostate tissue, with highest staining intensities found in PCa. Overexpression of TRPM4 in PCa (combination of high...

  9. Comprehensive Analysis of Varicella-Zoster Virus Proteins Using a New Monoclonal Antibody Collection

    Science.gov (United States)

    Lenac Roviš, Tihana; Bailer, Susanne M.; Pothineni, Venkata R.; Ouwendijk, Werner J. D.; Šimić, Hrvoje; Babić, Marina; Miklić, Karmela; Malić, Suzana; Verweij, Marieke C.; Baiker, Armin; Gonzalez, Orland; von Brunn, Albrecht; Zimmer, Ralf; Früh, Klaus; Verjans, Georges M. G. M.

    2013-01-01

    Varicella-zoster virus (VZV) is the etiological agent of chickenpox and shingles. Due to the virus's restricted host and cell type tropism and the lack of tools for VZV proteomics, it is one of the least-characterized human herpesviruses. We generated 251 monoclonal antibodies (MAbs) against 59 of the 71 (83%) currently known unique VZV proteins to characterize VZV protein expression in vitro and in situ. Using this new set of MAbs, 44 viral proteins were detected by Western blotting (WB) and indirect immunofluorescence (IF); 13 were detected by WB only, and 2 were detected by IF only. A large proportion of viral proteins was analyzed for the first time in the context of virus infection. Our study revealed the subcellular localization of 46 proteins, 14 of which were analyzed in detail by confocal microscopy. Seven viral proteins were analyzed in time course experiments and showed a cascade-like temporal gene expression pattern similar to those of other herpesviruses. Furthermore, selected MAbs tested positive on human skin lesions by using immunohistochemistry, demonstrating the wide applicability of the MAb collection. Finally, a significant portion of the VZV-specific antibodies reacted with orthologs of simian varicella virus (SVV), thus enabling the systematic analysis of varicella in a nonhuman primate model system. In summary, this study provides insight into the potential function of numerous VZV proteins and novel tools to systematically study VZV and SVV pathogenesis. PMID:23596286

  10. Nasopharyngeal Protein Biomarkers of Acute Respiratory Virus Infection

    Directory of Open Access Journals (Sweden)

    Thomas W. Burke

    2017-03-01

    Full Text Available Infection of respiratory mucosa with viral pathogens triggers complex immunologic events in the affected host. We sought to characterize this response through proteomic analysis of nasopharyngeal lavage in human subjects experimentally challenged with influenza A/H3N2 or human rhinovirus, and to develop targeted assays measuring peptides involved in this host response allowing classification of acute respiratory virus infection. Unbiased proteomic discovery analysis identified 3285 peptides corresponding to 438 unique proteins, and revealed that infection with H3N2 induces significant alterations in protein expression. These include proteins involved in acute inflammatory response, innate immune response, and the complement cascade. These data provide insights into the nature of the biological response to viral infection of the upper respiratory tract, and the proteins that are dysregulated by viral infection form the basis of signature that accurately classifies the infected state. Verification of this signature using targeted mass spectrometry in independent cohorts of subjects challenged with influenza or rhinovirus demonstrates that it performs with high accuracy (0.8623 AUROC, 75% TPR, 97.46% TNR. With further development as a clinical diagnostic, this signature may have utility in rapid screening for emerging infections, avoidance of inappropriate antibacterial therapy, and more rapid implementation of appropriate therapeutic and public health strategies.

  11. Gene silencing and gene expression in phytopathogenic fungi using a plant virus vector.

    Science.gov (United States)

    Mascia, Tiziana; Nigro, Franco; Abdallah, Alì; Ferrara, Massimo; De Stradis, Angelo; Faedda, Roberto; Palukaitis, Peter; Gallitelli, Donato

    2014-03-18

    RNA interference (RNAi) is a powerful approach for elucidating gene functions in a variety of organisms, including phytopathogenic fungi. In such fungi, RNAi has been induced by expressing hairpin RNAs delivered through plasmids, sequences integrated in fungal or plant genomes, or by RNAi generated in planta by a plant virus infection. All these approaches have some drawbacks ranging from instability of hairpin constructs in fungal cells to difficulties in preparing and handling transgenic plants to silence homologous sequences in fungi grown on these plants. Here we show that RNAi can be expressed in the phytopathogenic fungus Colletotrichum acutatum (strain C71) by virus-induced gene silencing (VIGS) without a plant intermediate, but by using the direct infection of a recombinant virus vector based on the plant virus, tobacco mosaic virus (TMV). We provide evidence that a wild-type isolate of TMV is able to enter C71 cells grown in liquid medium, replicate, and persist therein. With a similar approach, a recombinant TMV vector carrying a gene for the ectopic expression of the green fluorescent protein (GFP) induced the stable silencing of the GFP in the C. acutatum transformant line 10 expressing GFP derived from C71. The TMV-based vector also enabled C. acutatum to transiently express exogenous GFP up to six subcultures and for at least 2 mo after infection, without the need to develop transformation technology. With these characteristics, we anticipate this approach will find wider application as a tool in functional genomics of filamentous fungi.

  12. The nucleocapsid protein of an enveloped plant virus, Tomato spotted wilt virus, facilitates long-distance movement of Tobacco mosaic virus hybrids.

    Science.gov (United States)

    Zhang, Yongqiang; Zhang, Chao; Li, Weimin

    2012-01-01

    To investigate the potential role(s) of the nucleocapsid (N) protein of Tomato spotted wilt virus (TSWV), the open reading frame for the N protein was expressed from a Tobacco mosaic virus (TMV)-based vector encoding only the TMV replicase proteins. In the absence of other TSWV-encoded proteins, the transiently expressed N protein facilitated long-distance movement of the TMV-based hybrids in transgenic Nicotiana benthamiana [NB-MP(+)] expressing movement protein of TMV, thus providing the functional demonstration of the N protein in long-distance RNA movement. Removal of the N-terminal 39 amino acids (N-NΔ39), the C-terminal 26 amino acids (N-CΔ26) or both of them (N-NΔ39CΔ26) abolished the long-distance movement function, indicating the essential role of both N- and C-terminus. In contrast, alanine substitution of the phenylalanines at positions 242 and 246 (N242/262A), two crucial amino acids for homotypic interaction of the N protein, had little effect, suggesting that the N protein could function in long-distance movement in the form of monomers. In addition, both the wild type N and the alanine mutant N242/262A hardly induced local symptoms in NB-MP(+) plants and TMV-MP transgenic N. tabacum cv. Xanthi. The deletion mutants N-NΔ39, N-CΔ26 and N-NΔ39CΔ26, however, induced apparent symptoms of necrotic ringspots, necrosis or chlorotic spots in all inoculated leaves. On the basis of these findings, the potential role of N during the TSWV infection was discussed. To our knowledge, this is the first report that the N protein of an enveloped plant virus functioned in long-distance movement. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Preparation of quadri-subtype influenza virus-like particles using bovine immunodeficiency virus gag protein

    Energy Technology Data Exchange (ETDEWEB)

    Tretyakova, Irina; Hidajat, Rachmat; Hamilton, Garrett; Horn, Noah; Nickols, Brian; Prather, Raphael O. [Medigen, Inc., 8420 Gas House Pike, Suite S, Frederick, MD (United States); Tumpey, Terrence M. [Influenza Division, Centers for Disease Control and Prevention, 1600 Clifton Road N.E., Atlanta, GA (United States); Pushko, Peter, E-mail: ppushko@medigen-usa.com [Medigen, Inc., 8420 Gas House Pike, Suite S, Frederick, MD (United States)

    2016-01-15

    Influenza VLPs comprised of hemagglutinin (HA), neuraminidase (NA), and matrix (M1) proteins have been previously used for immunological and virological studies. Here we demonstrated that influenza VLPs can be made in Sf9 cells by using the bovine immunodeficiency virus gag (Bgag) protein in place of M1. We showed that Bgag can be used to prepare VLPs for several influenza subtypes including H1N1 and H10N8. Furthermore, by using Bgag, we prepared quadri-subtype VLPs, which co-expressed within the VLP the four HA subtypes derived from avian-origin H5N1, H7N9, H9N2 and H10N8 viruses. VLPs showed hemagglutination and neuraminidase activities and reacted with specific antisera. The content and co-localization of each HA subtype within the quadri-subtype VLP were evaluated. Electron microscopy showed that Bgag-based VLPs resembled influenza virions with the diameter of 150–200 nm. This is the first report of quadri-subtype design for influenza VLP and the use of Bgag for influenza VLP preparation. - Highlights: • BIV gag protein was configured as influenza VLP core component. • Recombinant influenza VLPs were prepared in Sf9 cells using baculovirus expression system. • Single- and quadri-subtype VLPs were prepared by using BIV gag as a VLP core. • Co-localization of H5, H7, H9, and H10 HA was confirmed within quadri-subtype VLP. • Content of HA subtypes within quadri-subtype VLP was determined. • Potential advantages of quadri-subtype VLPs as influenza vaccine are discussed.

  14. Epstein Barr virus latent membrane protein-1 in Hodgkin's ...

    African Journals Online (AJOL)

    Epstein-Barr virus latent membrane protein-1 (LMP-1), CD15 and CD30 immunohistochemistry was also performed. The clinical characteristics of each patient were documented. Objectives: To document the frequency of involvement of Epstein-Barr virus in cases of HL seen in a university hospital in Nigeria. Results: Out of ...

  15. Multiple proteins of White spot syndrome virus involved in ...

    Indian Academy of Sciences (India)

    The recognition and attachment of virus to its host cell surface is a critical step for viral infection. Recent research revealed that -integrin was involved in White spot syndrome virus (WSSV) infection. In this study, the interaction of -integrin with structure proteins of WSSV and motifs involved in WSSV infection was ...

  16. Multiple proteins of White spot syndrome virus involved in ...

    Indian Academy of Sciences (India)

    2014-03-20

    Mar 20, 2014 ... The recognition and attachment of virus to its host cell surface is a critical step for viral infection. Recent research revealed that β-integrin was involved in White spot syndrome virus (WSSV) infection. In this study, the interaction of β-integrin with structure proteins of WSSV and motifs involved in WSSV ...

  17. X: On the molecular biology of the hepatitis B virus X protein

    NARCIS (Netherlands)

    van de Klundert, M.A.A.

    2016-01-01

    Expression of the hepatitis B virus (HBV) accessory protein HBx is a requirement for viral replication. In this thesis, we investigated how HBx supports HBV replication, and we performed studies to identify its function. In chapter 2 we show that the overlap of reading frames in the HBV genome

  18. Kinetics of Antigen Expression and Epitope Presentation during Virus Infection

    Science.gov (United States)

    Croft, Nathan P.; Smith, Stewart A.; Wong, Yik Chun; Tan, Chor Teck; Dudek, Nadine L.; Flesch, Inge E. A.; Lin, Leon C. W.; Tscharke, David C.; Purcell, Anthony W.

    2013-01-01

    Current knowledge about the dynamics of antigen presentation to T cells during viral infection is very poor despite being of fundamental importance to our understanding of anti-viral immunity. Here we use an advanced mass spectrometry method to simultaneously quantify the presentation of eight vaccinia virus peptide-MHC complexes (epitopes) on infected cells and the amounts of their source antigens at multiple times after infection. The results show a startling 1000-fold range in abundance as well as strikingly different kinetics across the epitopes monitored. The tight correlation between onset of protein expression and epitope display for most antigens provides the strongest support to date that antigen presentation is largely linked to translation and not later degradation of antigens. Finally, we show a complete disconnect between the epitope abundance and immunodominance hierarchy of these eight epitopes. This study highlights the complexity of viral antigen presentation by the host and demonstrates the weakness of simple models that assume total protein levels are directly linked to epitope presentation and immunogenicity. PMID:23382674

  19. The African Swine Fever Virus Virion Membrane Protein pE248R Is Required for Virus Infectivity and an Early Postentry Event ▿

    Science.gov (United States)

    Rodríguez, Irene; Nogal, María L.; Redrejo-Rodríguez, Modesto; Bustos, María J.; Salas, María L.

    2009-01-01

    The African swine fever virus (ASFV) protein pE248R, encoded by the gene E248R, is a late structural component of the virus particle. The protein contains intramolecular disulfide bonds and has been previously identified as a substrate of the ASFV-encoded redox system. Its amino acid sequence contains a putative myristoylation site and a hydrophobic transmembrane region near its carboxy terminus. We show here that the protein pE248R is myristoylated during infection and associates with the membrane fraction in infected cells, behaving as an integral membrane protein. Furthermore, the protein localizes at the inner envelope of the virus particles in the cytoplasmic factories. The function of the protein pE248R in ASFV replication was investigated by using a recombinant virus that inducibly expresses the gene E248R. Under repressive conditions, the ASFV polyproteins pp220 and pp62 are normally processed and virus particles with morphology indistinguishable from that of those produced in a wild-type infection or under permissive conditions are generated. Moreover, the mutant virus particles can exit the cell as does the parental virus. However, the infectivity of the pE248R-deficient virions was reduced at least 100-fold. An investigation of the defect of the mutant virus indicated that neither virus binding nor internalization was affected by the absence of the protein pE248R, but a cytopathic effect was not induced and early and late gene expression was impaired, indicating that the protein is required for some early postentry event. PMID:19793823

  20. The African swine fever virus virion membrane protein pE248R is required for virus infectivity and an early postentry event.

    Science.gov (United States)

    Rodríguez, Irene; Nogal, María L; Redrejo-Rodríguez, Modesto; Bustos, María J; Salas, María L

    2009-12-01

    The African swine fever virus (ASFV) protein pE248R, encoded by the gene E248R, is a late structural component of the virus particle. The protein contains intramolecular disulfide bonds and has been previously identified as a substrate of the ASFV-encoded redox system. Its amino acid sequence contains a putative myristoylation site and a hydrophobic transmembrane region near its carboxy terminus. We show here that the protein pE248R is myristoylated during infection and associates with the membrane fraction in infected cells, behaving as an integral membrane protein. Furthermore, the protein localizes at the inner envelope of the virus particles in the cytoplasmic factories. The function of the protein pE248R in ASFV replication was investigated by using a recombinant virus that inducibly expresses the gene E248R. Under repressive conditions, the ASFV polyproteins pp220 and pp62 are normally processed and virus particles with morphology indistinguishable from that of those produced in a wild-type infection or under permissive conditions are generated. Moreover, the mutant virus particles can exit the cell as does the parental virus. However, the infectivity of the pE248R-deficient virions was reduced at least 100-fold. An investigation of the defect of the mutant virus indicated that neither virus binding nor internalization was affected by the absence of the protein pE248R, but a cytopathic effect was not induced and early and late gene expression was impaired, indicating that the protein is required for some early postentry event.

  1. MOPED: Model Organism Protein Expression Database

    OpenAIRE

    Kolker, Eugene; Higdon, Roger; Haynes, Winston; Welch, Dean; Broomall, William; Lancet, Doron; Stanberry, Larissa; Kolker, Natali

    2011-01-01

    Large numbers of mass spectrometry proteomics studies are being conducted to understand all types of biological processes. The size and complexity of proteomics data hinders efforts to easily share, integrate, query and compare the studies. The Model Organism Protein Expression Database (MOPED, htttp://moped.proteinspire.org) is a new and expanding proteomics resource that enables rapid browsing of protein expression information from publicly available studies on humans and model organisms. M...

  2. Phloem protein partners of Cucurbit aphid borne yellows virus: possible involvement of phloem proteins in virus transmission by aphids.

    Science.gov (United States)

    Bencharki, B; Boissinot, S; Revollon, S; Ziegler-Graff, V; Erdinger, M; Wiss, L; Dinant, S; Renard, D; Beuve, M; Lemaitre-Guillier, C; Brault, V

    2010-06-01

    Poleroviruses are phytoviruses strictly transmitted by phloem-feeding aphids in a circulative and nonpropagative mode. During ingestion, aphids sample virions in sieve tubes along with sap. Therefore, any sap protein bound to virions will be acquired by the insects and could potentially be involved in the transmission process. By developing in vitro virus-overlay assays on sap proteins collected from cucumber, we observed that approximately 20 proteins were able to bind to purified particles of Cucurbit aphid borne yellows virus (CABYV). Among them, eight proteins were identified by mass spectrometry. The role of two candidates belonging to the PP2-like family (predominant lectins found in cucurbit sap) in aphid transmission was further pursued by using purified orthologous PP2 proteins from Arabidopsis. Addition of these proteins to the virus suspension in the aphid artificial diet greatly increased virus transmission rate. This shift was correlated with an increase in the number of viral genomes in insect cells and with an increase of virion stability in vitro. Surprisingly, increase of the virus transmission rate was also monitored after addition of unrelated proteins in the aphid diet, suggesting that any soluble protein at sufficiently high concentration in the diet and acquired together with virions could stimulate virus transmission.

  3. Evasion of antiviral innate immunity by Theiler's virus L* protein through direct inhibition of RNase L.

    Directory of Open Access Journals (Sweden)

    Frédéric Sorgeloos

    Full Text Available Theiler's virus is a neurotropic picornavirus responsible for chronic infections of the central nervous system. The establishment of a persistent infection and the subsequent demyelinating disease triggered by the virus depend on the expression of L*, a viral accessory protein encoded by an alternative open reading frame of the virus. We discovered that L* potently inhibits the interferon-inducible OAS/RNase L pathway. The antagonism of RNase L by L* was particularly prominent in macrophages where baseline oligoadenylate synthetase (OAS and RNase L expression levels are elevated, but was detectable in fibroblasts after IFN pretreatment. L* mutations significantly affected Theiler's virus replication in primary macrophages derived from wild-type but not from RNase L-deficient mice. L* counteracted the OAS/RNase L pathway through direct interaction with the ankyrin domain of RNase L, resulting in the inhibition of this enzyme. Interestingly, RNase L inhibition was species-specific as Theiler's virus L* protein blocked murine RNase L but not human RNase L or RNase L of other mammals or birds. Direct RNase L inhibition by L* and species specificity were confirmed in an in vitro assay performed with purified proteins. These results demonstrate a novel viral mechanism to elude the antiviral OAS/RNase L pathway. By targeting the effector enzyme of this antiviral pathway, L* potently inhibits RNase L, underscoring the importance of this enzyme in innate immunity against Theiler's virus.

  4. Evasion of Antiviral Innate Immunity by Theiler's Virus L* Protein through Direct Inhibition of RNase L

    Science.gov (United States)

    Sorgeloos, Frédéric; Jha, Babal Kant; Silverman, Robert H.; Michiels, Thomas

    2013-01-01

    Theiler's virus is a neurotropic picornavirus responsible for chronic infections of the central nervous system. The establishment of a persistent infection and the subsequent demyelinating disease triggered by the virus depend on the expression of L*, a viral accessory protein encoded by an alternative open reading frame of the virus. We discovered that L* potently inhibits the interferon-inducible OAS/RNase L pathway. The antagonism of RNase L by L* was particularly prominent in macrophages where baseline oligoadenylate synthetase (OAS) and RNase L expression levels are elevated, but was detectable in fibroblasts after IFN pretreatment. L* mutations significantly affected Theiler's virus replication in primary macrophages derived from wild-type but not from RNase L-deficient mice. L* counteracted the OAS/RNase L pathway through direct interaction with the ankyrin domain of RNase L, resulting in the inhibition of this enzyme. Interestingly, RNase L inhibition was species-specific as Theiler's virus L* protein blocked murine RNase L but not human RNase L or RNase L of other mammals or birds. Direct RNase L inhibition by L* and species specificity were confirmed in an in vitro assay performed with purified proteins. These results demonstrate a novel viral mechanism to elude the antiviral OAS/RNase L pathway. By targeting the effector enzyme of this antiviral pathway, L* potently inhibits RNase L, underscoring the importance of this enzyme in innate immunity against Theiler's virus. PMID:23825954

  5. Tinkering with Translation: Protein Synthesis in Virus-Infected Cells

    Science.gov (United States)

    Walsh, Derek; Mathews, Michael B.; Mohr, Ian

    2013-01-01

    Viruses are obligate intracellular parasites, and their replication requires host cell functions. Although the size, composition, complexity, and functions encoded by their genomes are remarkably diverse, all viruses rely absolutely on the protein synthesis machinery of their host cells. Lacking their own translational apparatus, they must recruit cellular ribosomes in order to translate viral mRNAs and produce the protein products required for their replication. In addition, there are other constraints on viral protein production. Crucially, host innate defenses and stress responses capable of inactivating the translation machinery must be effectively neutralized. Furthermore, the limited coding capacity of the viral genome needs to be used optimally. These demands have resulted in complex interactions between virus and host that exploit ostensibly virus-specific mechanisms and, at the same time, illuminate the functioning of the cellular protein synthesis apparatus. PMID:23209131

  6. Expression, Delivery and Function of Insecticidal Proteins Expressed by Recombinant Baculoviruses

    Directory of Open Access Journals (Sweden)

    Jeremy A. Kroemer

    2015-01-01

    Full Text Available Since the development of methods for inserting and expressing genes in baculoviruses, a line of research has focused on developing recombinant baculoviruses that express insecticidal peptides and proteins. These recombinant viruses have been engineered with the goal of improving their pesticidal potential by shortening the time required for infection to kill or incapacitate insect pests and reducing the quantity of crop damage as a consequence. A wide variety of neurotoxic peptides, proteins that regulate insect physiology, degradative enzymes, and other potentially insecticidal proteins have been evaluated for their capacity to reduce the survival time of baculovirus-infected lepidopteran host larvae. Researchers have investigated the factors involved in the efficient expression and delivery of baculovirus-encoded insecticidal peptides and proteins, with much effort dedicated to identifying ideal promoters for driving transcription and signal peptides that mediate secretion of the expressed target protein. Other factors, particularly translational efficiency of transcripts derived from recombinant insecticidal genes and post-translational folding and processing of insecticidal proteins, remain relatively unexplored. The discovery of RNA interference as a gene-specific regulation mechanism offers a new approach for improvement of baculovirus biopesticidal efficacy through genetic modification.

  7. The cellular endosomal protein stannin inhibits intracellular trafficking of human papillomavirus during virus entry.

    Science.gov (United States)

    Lipovsky, Alex; Erden, Asu; Kanaya, Eriko; Zhang, Wei; Crite, Mac; Bradfield, Clinton; MacMicking, John; DiMaio, Daniel; Schoggins, John W; Iwasaki, Akiko

    2017-10-23

    Human papillomaviruses (HPVs) are the most common sexually transmitted viruses and one of the most important infectious causes of cancers worldwide. While prophylactic vaccines are effective against certain strains of HPV, established infections still cause deadly cancers in both men and women. HPV traffics to the nucleus via the retrograde transport pathway, but the mechanism of intracellular transport of non-enveloped viruses such as HPV is incompletely understood. Using an overexpression screen, we identify several genes that control HPV16 entry. We focused on the mechanism by which one of the screen hits, stannin, blocks HPV16 infection. Stannin has not been previously implicated in virus entry. Overexpression of stannin specifically inhibits infection by several HPV types, but not other viruses tested. Stannin is constitutively expressed in human keratinocytes, and its basal levels limit entry by HPV16. Stannin is localized to the endolysosomal compartment and does not affect HPV16 binding to cells, virus uptake, or virus uncoating, but inhibits the entry of HPV into the trans-Golgi network (TGN) and stimulates HPV degradation. We further show that stannin interacts with L1 major capsid protein and impairs the interaction of the L2 minor capsid protein with retromer, which is required for virus trafficking to the TGN. Our findings shed light on a novel cellular protein that interferes with HPV entry and highlight the role of retrograde transport in HPV entry.

  8. Functional Analysis of Glycosylation of Zika Virus Envelope Protein

    OpenAIRE

    Camila R. Fontes-Garfias; Chao Shan; Huanle Luo; Muruato, Antonio E.; Medeiros, Daniele B.A.; Elizabeth Mays; Xuping Xie; Jing Zou; Roundy, Christopher M; Maki Wakamiya; Rossi, Shannan L.; Tian Wang; Weaver, Scott C.; Pei-Yong Shi

    2017-01-01

    Summary: Zika virus (ZIKV) infection causes devastating congenital abnormities and Guillain-Barré syndrome. The ZIKV envelope (E) protein is responsible for viral entry and represents a major determinant for viral pathogenesis. Like other flaviviruses, the ZIKV E protein is glycosylated at amino acid N154. To study the function of E glycosylation, we generated a recombinant N154Q ZIKV that lacks the E glycosylation and analyzed the mutant virus in mammalian and mosquito hosts. In mouse models...

  9. Recombinant measles virus vaccine expressing the Nipah virus glycoprotein protects against lethal Nipah virus challenge.

    Directory of Open Access Journals (Sweden)

    Misako Yoneda

    Full Text Available Nipah virus (NiV is a member of the genus Henipavirus, which emerged in Malaysia in 1998. In pigs, infection resulted in a predominantly non-lethal respiratory disease; however, infection in humans resulted in over 100 deaths. Nipah virus has continued to re-emerge in Bangladesh and India, and person-to-person transmission appeared in the outbreak. Although a number of NiV vaccine studies have been reported, there are currently no vaccines or treatments licensed for human use. In this study, we have developed a recombinant measles virus (rMV vaccine expressing NiV envelope glycoproteins (rMV-HL-G and rMV-Ed-G. Vaccinated hamsters were completely protected against NiV challenge, while the mortality of unvaccinated control hamsters was 90%. We trialed our vaccine in a non-human primate model, African green monkeys. Upon intraperitoneal infection with NiV, monkeys showed several clinical signs of disease including severe depression, reduced ability to move and decreased food ingestion and died at 7 days post infection (dpi. Intranasal and oral inoculation induced similar clinical illness in monkeys, evident around 9 dpi, and resulted in a moribund stage around 14 dpi. Two monkeys immunized subcutaneously with rMV-Ed-G showed no clinical illness prior to euthanasia after challenge with NiV. Viral RNA was not detected in any organ samples collected from vaccinated monkeys, and no pathological changes were found upon histopathological examination. From our findings, we propose that rMV-NiV-G is an appropriate NiV vaccine candidate for use in humans.

  10. Recombinant measles virus vaccine expressing the Nipah virus glycoprotein protects against lethal Nipah virus challenge.

    Science.gov (United States)

    Yoneda, Misako; Georges-Courbot, Marie-Claude; Ikeda, Fusako; Ishii, Miho; Nagata, Noriyo; Jacquot, Frederic; Raoul, Hervé; Sato, Hiroki; Kai, Chieko

    2013-01-01

    Nipah virus (NiV) is a member of the genus Henipavirus, which emerged in Malaysia in 1998. In pigs, infection resulted in a predominantly non-lethal respiratory disease; however, infection in humans resulted in over 100 deaths. Nipah virus has continued to re-emerge in Bangladesh and India, and person-to-person transmission appeared in the outbreak. Although a number of NiV vaccine studies have been reported, there are currently no vaccines or treatments licensed for human use. In this study, we have developed a recombinant measles virus (rMV) vaccine expressing NiV envelope glycoproteins (rMV-HL-G and rMV-Ed-G). Vaccinated hamsters were completely protected against NiV challenge, while the mortality of unvaccinated control hamsters was 90%. We trialed our vaccine in a non-human primate model, African green monkeys. Upon intraperitoneal infection with NiV, monkeys showed several clinical signs of disease including severe depression, reduced ability to move and decreased food ingestion and died at 7 days post infection (dpi). Intranasal and oral inoculation induced similar clinical illness in monkeys, evident around 9 dpi, and resulted in a moribund stage around 14 dpi. Two monkeys immunized subcutaneously with rMV-Ed-G showed no clinical illness prior to euthanasia after challenge with NiV. Viral RNA was not detected in any organ samples collected from vaccinated monkeys, and no pathological changes were found upon histopathological examination. From our findings, we propose that rMV-NiV-G is an appropriate NiV vaccine candidate for use in humans.

  11. Temporal protein expression pattern in intracellular signalling ...

    Indian Academy of Sciences (India)

    2015-09-28

    Sep 28, 2015 ... 1. Introduction. Exhibition of diverse patterns in the biological world has been ... molecular biology, genomics and proteomics experiments have come up with ..... proteins at 0, 2, 4 and 6 h, (B) temporal protein expression pattern observed in synchronous update up to 21 time points (0 to 10 h), (C) temporal ...

  12. Evaluation of Measles Vaccine Virus as a Vector to Deliver Respiratory Syncytial Virus Fusion Protein or Epstein-Barr Virus Glycoprotein gp350.

    Science.gov (United States)

    Mok, Hoyin; Cheng, Xing; Xu, Qi; Zengel, James R; Parhy, Bandita; Zhao, Jackie; Wang, C Kathy; Jin, Hong

    2012-01-01

    Live attenuated recombinant measles vaccine virus (MV) Edmonston-Zagreb (EZ) strain was evaluated as a viral vector to express the ectodomains of fusion protein of respiratory syncytial virus (RSV F) or glycoprotein 350 of Epstein-Barr virus (EBV gp350) as candidate vaccines for prophylaxis of RSV and EBV. The glycoprotein gene was inserted at the 1(st) or the 3(rd) position of the measles virus genome and the recombinant viruses were generated. Insertion of the foreign gene at the 3(rd) position had a minimal impact on viral replication in vitro. RSV F or EBV gp350 protein was secreted from infected cells. In cotton rats, EZ-RSV F and EZ-EBV gp350 induced MV- and insert-specific antibody responses. In addition, both vaccines also induced insert specific interferon gamma (IFN-γ) secreting T cell response. EZ-RSV F protected cotton rats from pulmonary replication of RSV A2 challenge infection. In rhesus macaques, although both EZ-RSV F and EZ-EBV gp350 induced MV specific neutralizing antibody responses, only RSV F specific antibody response was detected. Thus, the immunogenicity of the foreign antigens delivered by measles vaccine virus is dependent on the nature of the insert and the animal models used for vaccine evaluation.

  13. Molecular Characterizations of Surface Proteins Hemagglutinin and Neuraminidase from Recent H5Nx Avian Influenza Viruses

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hua; Carney, Paul J.; Mishin, Vasiliy P.; Guo, Zhu; Chang, Jessie C.; Wentworth, David E.; Gubareva, Larisa V.; Stevens, James; Schultz-Cherry, S.

    2016-04-06

    ABSTRACT

    During 2014, a subclade 2.3.4.4 highly pathogenic avian influenza (HPAI) A(H5N8) virus caused poultry outbreaks around the world. In late 2014/early 2015, the virus was detected in wild birds in Canada and the United States, and these viruses also gave rise to reassortant progeny, composed of viral RNA segments (vRNAs) from both Eurasian and North American lineages. In particular, viruses were found with N1, N2, and N8 neuraminidase vRNAs, and these are collectively referred to as H5Nx viruses. In the United States, more than 48 million domestic birds have been affected. Here we present a detailed structural and biochemical analysis of the surface antigens of H5N1, H5N2, and H5N8 viruses in addition to those of a recent human H5N6 virus. Our results with recombinant hemagglutinin reveal that these viruses have a strict avian receptor binding preference, while recombinantly expressed neuraminidases are sensitive to FDA-approved and investigational antivirals. Although H5Nx viruses currently pose a low risk to humans, it is important to maintain surveillance of these circulating viruses and to continually assess future changes that may increase their pandemic potential.

    IMPORTANCEThe H5Nx viruses emerging in North America, Europe, and Asia pose a great public health concern. Here we report a molecular and structural study of the major surface proteins of several H5Nx influenza viruses. Our results improve the understanding of these new viruses and provide important information on their receptor preferences and susceptibilities to antivirals, which are central to pandemic risk assessment.

  14. A single vertebrate DNA virus protein disarms invertebrate immunity to RNA virus infection

    Science.gov (United States)

    Gammon, Don B; Duraffour, Sophie; Rozelle, Daniel K; Hehnly, Heidi; Sharma, Rita; Sparks, Michael E; West, Cara C; Chen, Ying; Moresco, James J; Andrei, Graciela; Connor, John H; Conte, Darryl; Gundersen-Rindal, Dawn E; Marshall, William L; Yates, John R; Silverman, Neal; Mello, Craig C

    2014-01-01

    Virus-host interactions drive a remarkable diversity of immune responses and countermeasures. We found that two RNA viruses with broad host ranges, vesicular stomatitis virus (VSV) and Sindbis virus (SINV), are completely restricted in their replication after entry into Lepidopteran cells. This restriction is overcome when cells are co-infected with vaccinia virus (VACV), a vertebrate DNA virus. Using RNAi screening, we show that Lepidopteran RNAi, Nuclear Factor-κB, and ubiquitin-proteasome pathways restrict RNA virus infection. Surprisingly, a highly conserved, uncharacterized VACV protein, A51R, can partially overcome this virus restriction. We show that A51R is also critical for VACV replication in vertebrate cells and for pathogenesis in mice. Interestingly, A51R colocalizes with, and stabilizes, host microtubules and also associates with ubiquitin. We show that A51R promotes viral protein stability, possibly by preventing ubiquitin-dependent targeting of viral proteins for destruction. Importantly, our studies reveal exciting new opportunities to study virus-host interactions in experimentally-tractable Lepidopteran systems. DOI: http://dx.doi.org/10.7554/eLife.02910.001 PMID:24966209

  15. Hemagglutinin-esterase-fusion (HEF protein of influenza C virus

    Directory of Open Access Journals (Sweden)

    Mingyang Wang

    2015-07-01

    Full Text Available ABSTRACT Influenza C virus, a member of the Orthomyxoviridae family, causes flu-like disease but typically only with mild symptoms. Humans are the main reservoir of the virus, but it also infects pigs and dogs. Very recently, influenza C-like viruses were isolated from pigs and cattle that differ from classical influenza C virus and might constitute a new influenza virus genus. Influenza C virus is unique since it contains only one spike protein, the hemagglutinin-esterase-fusion glycoprotein HEF that possesses receptor binding, receptor destroying and membrane fusion activities, thus combining the functions of Hemagglutinin (HA and Neuraminidase (NA of influenza A and B viruses. Here we briefly review the epidemiology and pathology of the virus and the morphology of virus particles and their genome. The main focus is on the structure of the HEF protein as well as on its co- and post-translational modification, such as N-glycosylation, disulfide bond formation, S-acylation and proteolytic cleavage into HEF1 and HEF2 subunits. Finally, we describe the functions of HEF: receptor binding, esterase activity and membrane fusion.

  16. Faster replication and higher expression levels of viral glycoproteins give the vesicular stomatitis virus/measles virus hybrid VSV-FH a growth advantage over measles virus.

    Science.gov (United States)

    Ayala-Breton, Camilo; Russell, Luke O J; Russell, Stephen J; Peng, Kah-Whye

    2014-08-01

    VSV-FH is a hybrid vesicular stomatitis virus (VSV) with a deletion of its G glycoprotein and encoding the measles virus (MV) fusion (F) and hemagglutinin (H) envelope glycoproteins. VSV-FH infects cells expressing MV receptors and is fusogenic and effective against myeloma xenografts in mice. We evaluated the fusogenic activities of MV and VSV-FH in relationship to the density of receptor on the target cell surface and the kinetics of F and H expression in infected cells. Using a panel of cells expressing increasing numbers of the MV receptor CD46, we evaluated syncytium size in MV- or VSV-FH-infected cells. VSV-FH is not fusogenic at low CD46 density but requires less CD46 for syncytium formation than MV. The size of each syncytium is larger in VSV-FH-infected cells at a specific CD46 density. While syncytium size reached a plateau and did not increase further in MV-infected CHO cells expressing ≥4,620 CD46 copies/cell, there was a corresponding increase in syncytium size with increases in CD46 levels in VSV-FH-infected CD46-expressing CHO (CHO-CD46) cells. Further analysis in VSV-FH-infected cell lines shows earlier and higher expression of F and H mRNAs and protein. However, VSV-FH cytotoxic activity was reduced by pretreatment of the cells with type I interferon. In contrast, the cytopathic effects are not affected in MV-infected cells. In summary, VSV-FH has significant advantages over MV as an oncolytic virus due to its higher viral yield, faster replication kinetics, and larger fusogenic capabilities but should be used in cancer types with defective interferon signaling pathways. We studied the cytotoxic activity of a vesicular stomatitis/measles hybrid virus (VSV-FH), which is superior to that of measles virus (MV), in different cancer cell lines. We determined that viral RNA and protein were produced faster and in higher quantities in VSV-FH-infected cells. This resulted in the formation of larger syncytia, higher production of infectious particles, and

  17. Using Resurrected Ancestral Proviral Proteins to Engineer Virus Resistance

    Directory of Open Access Journals (Sweden)

    Asunción Delgado

    2017-05-01

    Full Text Available Proviral factors are host proteins hijacked by viruses for processes essential for virus propagation such as cellular entry and replication. Pathogens and their hosts co-evolve. It follows that replacing a proviral factor with a functional ancestral form of the same protein could prevent viral propagation without fatally compromising organismal fitness. Here, we provide proof of concept of this notion. Thioredoxins serve as general oxidoreductases in all known cells. We report that several laboratory resurrections of Precambrian thioredoxins display substantial levels of functionality within Escherichia coli. Unlike E. coli thioredoxin, however, these ancestral thioredoxins are not efficiently recruited by the bacteriophage T7 for its replisome and therefore prevent phage propagation in E. coli. These results suggest an approach to the engineering of virus resistance. Diseases caused by viruses may have a devastating effect in agriculture. We discuss how the suggested approach could be applied to the engineering of plant virus resistance.

  18. Unfolded protein response in hepatitis C virus infection

    Directory of Open Access Journals (Sweden)

    Shiu-Wan eChan

    2014-05-01

    Full Text Available Hepatitis C virus (HCV is a single-stranded, positive-sense RNA virus of clinical importance. The virus establishes a chronic infection and can progress from chronic hepatitis, steatosis to fibrosis, cirrhosis and hepatocellular carcinoma. The mechanisms of viral persistence and pathogenesis are poorly understood. Recently the unfolded protein response (UPR, a cellular homeostatic response to endoplasmic reticulum (ER stress, has emerged to be a major contributing factor in many human diseases. It is also evident that viruses interact with the host UPR in many different ways and the outcome could be pro-viral, anti-viral or pathogenic, depending on the particular type of infection. Here we present evidence for the elicitation of chronic ER stress in HCV infection. We analyze the UPR signaling pathways involved in HCV infection, the various levels of UPR regulation by different viral proteins and finally, we propose several mechanisms by which the virus provokes the UPR.

  19. Viroporin Activity of the Foot-and-Mouth Disease Virus Non-Structural 2B Protein.

    Directory of Open Access Journals (Sweden)

    Da Ao

    Full Text Available Viroporins are a family of low-molecular-weight hydrophobic transmembrane proteins that are encoded by various animal viruses. Viroporins form transmembrane pores in host cells via oligomerization, thereby destroying cellular homeostasis and inducing cytopathy for virus replication and virion release. Among the Picornaviridae family of viruses, the 2B protein encoded by enteroviruses is well understood, whereas the viroporin activity of the 2B protein encoded by the foot-and-mouth disease virus (FMDV has not yet been described. An analysis of the FMDV 2B protein domains by computer-aided programs conducted in this study revealed that this protein may contain two transmembrane regions. Further biochemical, biophysical and functional studies revealed that the protein possesses a number of features typical of a viroporin when it is overexpressed in bacterial and mammalian cells as well as in FMDV-infected cells. The protein was found to be mainly localized in the endoplasmic reticulum (ER, with both the N- and C-terminal domains stretched into the cytosol. It exhibited cytotoxicity in Escherichia coli, which attenuated 2B protein expression. The release of virions from cells infected with FMDV was inhibited by amantadine, a viroporin inhibitor. The 2B protein monomers interacted with each other to form both intracellular and extracellular oligomers. The Ca(2+ concentration in the cells increased, and the integrity of the cytoplasmic membrane was disrupted in cells that expressed the 2B protein. Moreover, the 2B protein induced intense autophagy in host cells. All of the results of this study demonstrate that the FMDV 2B protein has properties that are also found in other viroporins and may be involved in the infection mechanism of FMDV.

  20. Relative contributions of measles virus hemagglutinin- and fusion protein- specific serum antibodies to virus neutralization.

    NARCIS (Netherlands)

    R.L. de Swart (Rik); S. Yüksel (Selma); A.D.M.E. Osterhaus (Albert)

    2005-01-01

    textabstractThe relative contribution of measles virus hemagglutinin (H)- or fusion protein (F)-specific antibodies to virus neutralization (VN) has not been demonstrated. We have depleted these specific antibodies from sera collected from young adults, who had been vaccinated during childhood, by

  1. Expression of multidrug resistance proteins in retinoblastoma

    Directory of Open Access Journals (Sweden)

    Swati Shukla

    2017-11-01

    Full Text Available AIM: To elucidate the mechanism of multidrug resistance in retinoblastoma, and to acquire more insights into in vivo drug resistance. METHODS: Three anticancer drug resistant Y79 human RB cells were generated against vincristine, etoposide or carboplatin, which are used for conventional chemotherapy in RB. Primary cultures from enucleated eyes after chemotherapy (PCNC were also prepared. Their chemosensitivity to chemotherapeutic agents (vincristine, etoposide and carboplatin were measured using MTT assay. Western blot analysis was performed to evaluate the expression of p53, Bcl-2 and various multidrug resistant proteins in retinoblastoma cells. RESULTS: Following exposure to chemotherapeutic drugs, PCNC showed less sensitivity to drugs. No significant changes observed in the p53 expression, whereas Bcl-2 expression was found to be increased in the drug resistant cells as well as in PCNC. Increased expression of P-glycoprotein (P-gp was observed in drug resistant Y79 cells; however there was no significant change in the expression of P-gp found between primary cultures of primarily enucleated eyes and PCNC. Multidrug resistance protein 1 (Mrp-1 expression was found to be elevated in the drug resistant Y79 cells as well as in PCNC. No significant change in the expression of lung resistance associated protein (Lrp was observed in the drug resistant Y79 cells as well as in PCNC. CONCLUSION: Our results suggest that multidrug resistant proteins are intrinsically present in retinoblastoma which causes treatment failure in managing retinoblastoma with chemotherapy.

  2. Expression of multidrug resistance proteins in retinoblastoma.

    Science.gov (United States)

    Shukla, Swati; Srivastava, Arpna; Kumar, Sunil; Singh, Usha; Goswami, Sandeep; Chawla, Bhavna; Bajaj, Mandeep Singh; Kashyap, Seema; Kaur, Jasbir

    2017-01-01

    To elucidate the mechanism of multidrug resistance in retinoblastoma, and to acquire more insights into in vivo drug resistance. Three anticancer drug resistant Y79 human RB cells were generated against vincristine, etoposide or carboplatin, which are used for conventional chemotherapy in RB. Primary cultures from enucleated eyes after chemotherapy (PCNC) were also prepared. Their chemosensitivity to chemotherapeutic agents (vincristine, etoposide and carboplatin) were measured using MTT assay. Western blot analysis was performed to evaluate the expression of p53, Bcl-2 and various multidrug resistant proteins in retinoblastoma cells. Following exposure to chemotherapeutic drugs, PCNC showed less sensitivity to drugs. No significant changes observed in the p53 expression, whereas Bcl-2 expression was found to be increased in the drug resistant cells as well as in PCNC. Increased expression of P-glycoprotein (P-gp) was observed in drug resistant Y79 cells; however there was no significant change in the expression of P-gp found between primary cultures of primarily enucleated eyes and PCNC. Multidrug resistance protein 1 (Mrp-1) expression was found to be elevated in the drug resistant Y79 cells as well as in PCNC. No significant change in the expression of lung resistance associated protein (Lrp) was observed in the drug resistant Y79 cells as well as in PCNC. Our results suggest that multidrug resistant proteins are intrinsically present in retinoblastoma which causes treatment failure in managing retinoblastoma with chemotherapy.

  3. RAGE inhibits human respiratory syncytial virus syncytium formation by interfering with F-protein function

    OpenAIRE

    Tian, Jane; Huang, Kelly; Krishnan, Subramaniam; Svabek, Catherine; Rowe, Daniel C.; Brewah, Yambasu; Sanjuan, Miguel; Patera, Andriani C.; Kolbeck, Roland; Herbst, Ronald; Sims, Gary P.

    2013-01-01

    Human respiratory syncytial virus (RSV) is a major cause of severe lower respiratory tract infection. Infection is critically dependent on the RSV fusion (F) protein, which mediates fusion between the viral envelope and airway epithelial cells. The F protein is also expressed on infected cells and is responsible for fusion of infected cells with adjacent cells, resulting in the formation of multinucleate syncytia. The receptor for advanced glycation end products (RAGE) is a pattern-recognitio...

  4. Analysis of VSV pseudotype virus infection mediated by rubella virus envelope proteins

    National Research Council Canada - National Science Library

    Masafumi Sakata; Hideki Tani; Masaki Anraku; Michiyo Kataoka; Noriyo Nagata; Fumio Seki; Maino Tahara; Noriyuki Otsuki; Kiyoko Okamoto; Makoto Takeda; Yoshio Mori

    2017-01-01

    .... To establish an infection the host cells must be susceptible and permissible. To assess the susceptibility of individual cell lines, we generated a pseudotype vesicular stomatitis virus bearing RV envelope proteins (VSV-RV/CE2E1...

  5. Transient Protein Expression by Agroinfiltration in Lettuce.

    Science.gov (United States)

    Chen, Qiang; Dent, Matthew; Hurtado, Jonathan; Stahnke, Jake; McNulty, Alyssa; Leuzinger, Kahlin; Lai, Huafang

    2016-01-01

    Current systems of recombinant protein production include bacterial, insect, and mammalian cell culture. However, these platforms are expensive to build and operate at commercial scales and/or have limited abilities to produce complex proteins. In recent years, plant-based expression systems have become top candidates for the production of recombinant proteins as they are highly scalable, robust, safe, and can produce complex proteins due to having a eukaryotic endomembrane system. Newly developed "deconstructed" viral vectors delivered via Agrobacterium tumefaciens (agroinfiltration) have enabled robust plant-based production of proteins with a wide range of applications. The leafy Lactuca sativa (lettuce) plant with its strong foundation in agriculture is an excellent host for pharmaceutical protein production. Here, we describe a method for agroinfiltration of lettuce that can rapidly produce high levels of recombinant proteins in a matter of days and has the potential to be scaled up to an agricultural level.

  6. [Internal epidemic influenza virus proteins: isolation and investigation].

    Science.gov (United States)

    Ivanova, V T; Rakutina, R O; Kordiukova, L V; Manykin, A A; Fedorova, N V; Ksenofontov, A L; Slepushkin, A N

    2006-01-01

    The internal influenza virus proteins M1 and RNP free from surface protein impurities were isolated from subviral particles (virions free from HA and NA ectomenes). The spikeless particles had no propensity to aggregate in the solution at pH 5.0 as compared with native viruses. The subviral particles of B/Hong Kong/330/01 influenza virus, which belonged to B/Victoria/2/87-lineage, were obtained by proteolytic treatment with the enzyme bromelain under the same conditions as in cases of influenza B viruses of B/Jamagata/16/88 lineage. A chromatographic analysis of the tryptic hydrolyzates obtained for matrix (M1) proteins of A(H1N1) and A(H3N2) influenza viruses revealed differences that were greatest between the protein M1 molecules isolated from influenza viruses of different subtypes of hemagglutinine. These findings suggest there are variations in the structure of this conservative internal viral protein M1 during evolution.

  7. Glycoprotein is enough for sindbis virus-derived DNA vector to express heterogenous genes

    Directory of Open Access Journals (Sweden)

    Fu Juanjuan

    2011-07-01

    Full Text Available Abstract To investigate the necessity and potential application of structural genes for expressing heterogenous genes from Sindbis virus-derived vector, the DNA-based expression vector pVaXJ was constructed by placing the recombinant genome of sindbis-like virus XJ-160 under the control of the human cytomegalovirus (CMV promoter of the plasmid pVAX1, in which viral structural genes were replaced by a polylinker cassette to allow for insertion of heterologous genes. The defect helper plasmids pVaE or pVaC were developed by cloning the gene of glycoprotein E3E26KE1 or capsid protein of XJ-160 virus into pVAX1, respectively. The report gene cassette pVaXJ-EGFP or pV-Gluc expressing enhanced green fluorescence protein (EGFP or Gaussia luciferase (G.luc were constructed by cloning EGFP or G.luc gene into pVaXJ. EGFP or G.luc was expressed in the BHK-21 cells co-transfected with report gene cassettes and pVaE at levels that were comparable to those produced by report gene cassettes, pVaC and pVaE and were much higher than the levels produced by report gene cassette and pVaC, suggesting that glycoprotein is enough for Sindbis virus-derived DNA vector to express heterogenous genes in host cells. The method of gene expression from Sindbis virus-based DNA vector only co-transfected with envelop E gene increase the conveniency and the utility of alphavirus-based vector systems in general.

  8. Inhibition of Translation Initiation by Protein 169: A Vaccinia Virus Strategy to Suppress Innate and Adaptive Immunity and Alter Virus Virulence.

    Directory of Open Access Journals (Sweden)

    Pavla Strnadova

    2015-09-01

    Full Text Available Vaccinia virus (VACV is the prototypic orthopoxvirus and the vaccine used to eradicate smallpox. Here we show that VACV strain Western Reserve protein 169 is a cytoplasmic polypeptide expressed early during infection that is excluded from virus factories and inhibits the initiation of cap-dependent and cap-independent translation. Ectopic expression of protein 169 causes the accumulation of 80S ribosomes, a reduction of polysomes, and inhibition of protein expression deriving from activation of multiple innate immune signaling pathways. A virus lacking 169 (vΔ169 replicates and spreads normally in cell culture but is more virulent than parental and revertant control viruses in intranasal and intradermal murine models of infection. Intranasal infection by vΔ169 caused increased pro-inflammatory cytokines and chemokines, infiltration of pulmonary leukocytes, and lung weight. These alterations in innate immunity resulted in a stronger CD8+ T-cell memory response and better protection against virus challenge. This work illustrates how inhibition of host protein synthesis can be a strategy for virus suppression of innate and adaptive immunity.

  9. Inhibition of Translation Initiation by Protein 169: A Vaccinia Virus Strategy to Suppress Innate and Adaptive Immunity and Alter Virus Virulence.

    Science.gov (United States)

    Strnadova, Pavla; Ren, Hongwei; Valentine, Robert; Mazzon, Michela; Sweeney, Trevor R; Brierley, Ian; Smith, Geoffrey L

    2015-09-01

    Vaccinia virus (VACV) is the prototypic orthopoxvirus and the vaccine used to eradicate smallpox. Here we show that VACV strain Western Reserve protein 169 is a cytoplasmic polypeptide expressed early during infection that is excluded from virus factories and inhibits the initiation of cap-dependent and cap-independent translation. Ectopic expression of protein 169 causes the accumulation of 80S ribosomes, a reduction of polysomes, and inhibition