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Sample records for antigens viral

  1. Radioimmunoassays of hidden viral antigens

    Energy Technology Data Exchange (ETDEWEB)

    Neurath, A.R. (Lindsley F. Kimbell Research Inst., New York, NY); Strick, N.; Baker, L.; Krugman, S.

    1982-07-01

    Antigens corresponding to infectious agents may be present in biological specimens only in a cryptic form bound to antibodies and, thus, may elude detection. We describe a solid-phase technique for separation of antigens from antibodies. Immune complexes are precipitated from serum by polyethylene glycol, dissociated with NaSCN, and adsorbed onto nitrocellulose or polystyrene supports. Antigens remain topographically separated from antibodies after removal of NaSCN and can be detected with radiolabeled antibodies. Genomes from viruses immobilized on nitrocellulose can be identified by nucleic acid hybridization. Nanogram quantities of sequestered hepatitis B surface and core antigens and picogram amounts of hepatitis B virus DNA were detected. Antibody-bound adenovirus, herpesvirus, and measles virus antigens were discerned by the procedure.

  2. Radioimmunoassays of hidden viral antigens.

    Science.gov (United States)

    Neurath, A R; Strick, N; Baker, L; Krugman, S

    1982-01-01

    Antigens corresponding to infectious agents may be present in biological specimens only in a cryptic form bound to antibodies and, thus, may elude detection. We describe a solid phase technique for separation of antigens from antibodies. Immune complexes are precipitated from serum by polyethylene glycol, dissociated with NaSCN, and adsorbed onto nitrocellulose or polystyrene supports. Antigens remain topographically separated from antibodies after removal of NaSCN and can be detected with radiolabeled antibodies. Genomes from viruses immobilized on nitrocellulose can be identified by nucleic acid hybridization. Nanogram quantities of sequestered hepatitis B surface and core antigens and picogram amounts of hepatitis B virus DNA were detected. Antibody-bond adenovirus, herpesvirus, and measles virus antigens were discerned by the procedure. Images PMID:6956871

  3. Viral immune evasion: Lessons in MHC class I antigen presentation.

    Science.gov (United States)

    van de Weijer, Michael L; Luteijn, Rutger D; Wiertz, Emmanuel J H J

    2015-03-01

    The MHC class I antigen presentation pathway enables cells infected with intracellular pathogens to signal the presence of the invader to the immune system. Cytotoxic T lymphocytes are able to eliminate the infected cells through recognition of pathogen-derived peptides presented by MHC class I molecules at the cell surface. In the course of evolution, many viruses have acquired inhibitors that target essential stages of the MHC class I antigen presentation pathway. Studies on these immune evasion proteins reveal fascinating strategies used by viruses to elude the immune system. Viral immunoevasins also constitute great research tools that facilitate functional studies on the MHC class I antigen presentation pathway, allowing the investigation of less well understood routes, such as TAP-independent antigen presentation and cross-presentation of exogenous proteins. Viral immunoevasins have also helped to unravel more general cellular processes. For instance, basic principles of ER-associated protein degradation via the ubiquitin-proteasome pathway have been resolved using virus-induced degradation of MHC class I as a model. This review highlights how viral immunoevasins have increased our understanding of MHC class I-restricted antigen presentation.

  4. Development of recombinant antigen array for simultaneous detection of viral antibodies.

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    Yi Liu

    Full Text Available Protein microarrays have been developed to study antibody reactivity against a large number of antigens, demonstrating extensive perspective for clinical application. We developed a viral antigen array by spotting four recombinant antigens and synthetic peptide, including glycoprotein G of herpes simplex virus (HSV type 1 and 2, phosphoprotein 150 of cytomegalovirus (CMV, Rubella virus (RV core plus glycoprotein E1 and E2 as well as a E1 peptide with the optimal concentrations on activated glass slides to simultaneously detect IgG and IgM against HSV1, HSV2, CMV and RV in clinical specimens of sera and cerebrospinal fluids (CSFs. The positive reference sera were initially used to measure the sensitivity and specificity of the array with the optimal conditions. Then clinical specimens of 144 sera and 93 CSFs were tested for IgG and IgM antibodies directed against HSV1, HSV2, CMV and RV by the antigen array. Specificity of the antigen array for viral antibodies detection was satisfying compared to commercial ELISA kits but sensitivity of the array varied relying on quality and antigenic epitopes of the spotting antigens. In short, the recombinant antigen array has potential to simultaneous detect multiple viral antibodies using minute amount (3 µl of samples, which holds the particularly advantage to detect viral antibodies in clinical CSFs being suspicious of neonatal meningitis and encephalitis.

  5. Detection of Avian Antigen-Specific T Cells Induced by Viral Vaccines

    DEFF Research Database (Denmark)

    Dalgaard, Tina Sørensen; Norup, Liselotte Rothmann; Juul-Madsen, Helle Risdahl

    2016-01-01

    Live attenuated viral vaccines are widely used in commercial poultry production, but the development of new effective inactivated/subunit vaccines is needed. Studies of avian antigen-specific T cells are primarily based on analyses ex vivo after activating the cells with recall antigen. There is ......Live attenuated viral vaccines are widely used in commercial poultry production, but the development of new effective inactivated/subunit vaccines is needed. Studies of avian antigen-specific T cells are primarily based on analyses ex vivo after activating the cells with recall antigen....... There is a particular interest in developing robust high-throughput assays as chicken vaccine trials usually comprise many individuals. In many respects, the avian immune system differs from the mammalian, and T cell assessment protocols must be adjusted accordingly to account for, e.g., differences in leukocyte...... responding to the stimulation. This method has been successfully applied to studies of chicken antigen-specific T cells....

  6. Identification, expression, and immunogenicity of Kaposi's sarcoma-associated herpesvirus-encoded small viral capsid antigen.

    OpenAIRE

    Lin, S F; Sun, R; Heston, L; Gradoville, L; Shedd, D; Haglund, K; Rigsby, M; Miller, G.

    1997-01-01

    We describe a recombinant antigen for use in serologic tests for antibodies to Kaposi's sarcoma (KS)-associated herpesvirus (KSHV). The cDNA for a small viral capsid antigen (sVCA) was identified by immunoscreening of a library prepared from the BC-1 body cavity lymphoma cell line induced into KSHV lytic gene expression by sodium butyrate. The cDNA specified a 170-amino-acid peptide with homology to small viral capsid proteins encoded by the BFRF3 gene of Epstein-Barr virus and the ORF65 gene...

  7. Potentiation of anthrax vaccines using protective antigen-expressing viral replicon vectors.

    Science.gov (United States)

    Wang, Hai-Chao; An, Huai-Jie; Yu, Yun-Zhou; Xu, Qing

    2015-02-01

    DNA vaccines require improvement for human use because they are generally weak stimulators of the immune system in humans. The efficacy of DNA vaccines can be improved using a viral replicon as vector to administer antigen of pathogen. In this study, we comprehensively evaluated the conventional non-viral DNA, viral replicon DNA or viral replicon particles (VRP) vaccines encoding different forms of anthrax protective antigen (PA) for specific immunity and protective potency against anthrax. Our current results clearly suggested that these viral replicon DNA or VRP vaccines derived from Semliki Forest virus (SFV) induced stronger PA-specific immune responses than the conventional non-viral DNA vaccines when encoding the same antigen forms, which resulted in potent protection against challenge with the Bacillus anthracis strain A16R. Additionally, the naked PA-expressing SFV replicon DNA or VRP vaccines without the need for high doses or demanding particular delivery regimens elicited robust immune responses and afforded completely protective potencies, which indicated the potential of the SFV replicon as vector of anthrax vaccines for use in clinical application. Therefore, our results suggest that these PA-expressing SFV replicon DNA or VRP vaccines may be suitable as candidate vaccines against anthrax.

  8. Bovine viral diarrhea virus antigen detection across whole cattle hides using two antigen-capture enzyme-linked immunosorbent assays.

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    Vander Ley, Brian L; Ridpath, Julia F; Sweiger, Shaun H

    2012-05-01

    Bovine viral diarrhea virus is a costly disease of cattle that can be controlled by vaccination, biosecurity, and removal of persistently infected cattle. Development and proficiency testing of assays to identify persistently infected cattle requires substantial quantities of known positive- and negative-sample material. The objective of this study was to determine what sections of bovine skin contained Bovine viral diarrhea virus antigen. Two commercially available antigen-capture enzyme-linked immunoassays were used to test subsamples representing the entire skin of 3 persistently infected calves. Both assays detected Bovine viral diarrhea virus antigen in the samples indicated for use by assay protocol. However, one assay identified all subsamples as positive, while the second assay identified 64.4% of subsamples as positive. These results show that use of samples other than those specified by the assay protocol must be validated for each individual assay. In this study, alternative sample sites and use of the entire hide for proficiency testing would be acceptable for only one of the assays tested.

  9. Viral hepatitis and hepatitis B antigen: recent advances

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    Krugman, Saul

    1974-01-01

    Recent advances in hepatitis research have shed new light on the etiology, pathogenesis, epidemiology and prevention of type B hepatitis infection. The so-called ‘Dane’ particle is probably the complete hepatitis B virion; its outer coat is the hepatitis B (Australia) antigen (HB Ag) and its inner core is an immunologically distinct particle. Subtypes of HB Ag (a, d, y, w and r) are useful indices for epidemiological surveys. Concepts of epidemiology have changed: type B hepatitis is transmissible by contact as well as by inoculation. The presence of HB Ag in blood is indicative of the presence of hepatitis B virus. Tests to detect antigen and use of voluntary blood donors have played a major role in the decreased incidence of post transfusion hepatitis. A special hepatitis B gammaglobulin preparation and a heat-inactivated hepatitis B vaccine have proved to be effective in preliminary studies. PMID:4219230

  10. Defining the HLA class I-associated viral antigen repertoire from HIV-1-infected human cells

    DEFF Research Database (Denmark)

    Ternette, Nicola; Yang, Hongbing; Partridge, Thomas

    2016-01-01

    % of the identified sequences originated from viral protein regions for which T-cell responses have previously been reported but for which the precise HLA class I-binding sequences have not yet been defined. These results validate and expand the current knowledge of virus-specific antigenic peptide presentation...

  11. Viral sequestration of antigen subverts cross presentation to CD8(+ T cells.

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    Eric F Tewalt

    2009-05-01

    Full Text Available Virus-specific CD8(+ T cells (T(CD8+ are initially triggered by peptide-MHC Class I complexes on the surface of professional antigen presenting cells (pAPC. Peptide-MHC complexes are produced by two spatially distinct pathways during virus infection. Endogenous antigens synthesized within virus-infected pAPC are presented via the direct-presentation pathway. Many viruses have developed strategies to subvert direct presentation. When direct presentation is blocked, the cross-presentation pathway, in which antigen is transferred from virus-infected cells to uninfected pAPC, is thought to compensate and allow the generation of effector T(CD8+. Direct presentation of vaccinia virus (VACV antigens driven by late promoters does not occur, as an abortive infection of pAPC prevents production of these late antigens. This lack of direct presentation results in a greatly diminished or ablated T(CD8+ response to late antigens. We demonstrate that late poxvirus antigens do not enter the cross-presentation pathway, even when identical antigens driven by early promoters access this pathway efficiently. The mechanism mediating this novel means of viral modulation of antigen presentation involves the sequestration of late antigens within virus factories. Early antigens and cellular antigens are cross-presented from virus-infected cells, as are late antigens that are targeted to compartments outside of the virus factories. This virus-mediated blockade specifically targets the cross-presentation pathway, since late antigen that is not cross-presented efficiently enters the MHC Class II presentation pathway. These data are the first to describe an evasion mechanism employed by pathogens to prevent entry into the cross-presentation pathway. In the absence of direct presentation, this evasion mechanism leads to a complete ablation of the T(CD8+ response and a potential replicative advantage for the virus. Such mechanisms of viral modulation of antigen presentation

  12. Antigen-loaded ER microsomes from APC induce potent immune responses against viral infection.

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    Sofra, Vassiliki; Mansour, Salah; Liu, Mengya; Gao, Bin; Primpidou, Elisavet; Wang, Ping; Li, Suling

    2009-01-01

    Although matured DC are capable of inducing effective primary and secondary immune responses in vivo, it is difficult to control the maturation and antigen loading in vitro. In this study, we show that ER-enriched microsomal membranes (microsomes) isolated from DC contain more peptide-receptive MHC I and II molecules than, and a similar level of costimulatory molecules to, their parental DC. After loading with defined antigenic peptides, the microsomes deliver antigenic peptide-MHC complexes (pMHC) to both CD4 and CD8 T cells effectively in vivo. The peptide-loaded microsomes accumulate in peripheral lymphoid organs and induce stronger immune responses than peptide-pulsed DC. The microsomal vaccines protect against acute viral infection. Our data demonstrate that peptide-MHC complexes armed microsomes from DC can be an important alternative to DC-based vaccines for protection from viral infection.

  13. Prevalence of African swine fever viral antigens in slaughter pigs at Nalukolongo abattoir, Kampala, Uganda

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    P. Sajjakambwe,

    2011-05-01

    Full Text Available The underdevelopment of the African pig industry is widely attributed to African swine fever (ASF. Outbreaks of the disease occur in different parts of Uganda almost annually although cases are rarely confirmed. We conducted an abattoir based survey of ASF associated lymph node lesions to establish the status of the disease in apparently healthy pigs. Highly suspicious lesions were subjected to immunohistochemistry for viral antigen detection. Most lymph nodes with follicular necrosis, parenchymal haemorrhage and lymphoid depletion were positive to ASF antigens. Up to 22 (0.1% of the 258 pigs from which samples were collected were positive to ASF viral antigens. We conclude that domestic pigs in Uganda can act as reservoirs of the disease i.e. sustenance of the disease in pig populations may not be entirely dependent on the sylvatic cycle.

  14. Pathology and viral antigen distribution following experimental infection of sheep and goats with capripoxvirus.

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    Embury-Hyatt, C; Babiuk, S; Manning, L; Ganske, S; Bowden, T R; Boyle, D B; Copps, J

    2012-01-01

    Current understanding of capripoxvirus pathogenesis is limited since there have been no detailed studies examining cell tropism at well-defined intervals following infection. We undertook time-course studies in sheep and goats following inoculation of sheeppox or goatpox viruses in their respective homologous hosts, and examined tissues by light microscopy. A monoclonal antibody generated to a sheeppox virus core protein was used for immunohistochemical detection of viral antigen in tissue sections. Lesions and virus antigen were observed consistently in the skin, lung and lymph nodes. Antigen was detected at 6 and 8 days post inoculation for skin and lung, respectively, within cells which appeared to be of monocyte/macrophage lineage. In sheep skin capripoxvirus immunoreactivity was detected within previously unreported large multinucleated cells. In the lung, double immunolabelling detected the simultaneous expression of capripoxvirus antigen and cytokeratin indicating the presence of virus within pneumocytes. Lung double immunolabelling also detected the expression of capripoxvirus antigen in CD68(+) cells, confirming the presence of viral antigen within macrophages. Based on early detection of infected macrophages, dissemination of virus within the host and localization to tissues likely occurred through cells of the monocyte/macrophage lineage. Histological findings revealed similarities with both monkeypox and smallpox, thus capripoxvirus infection in sheep and goats may represent useful models with which to study strategies for poxvirus-specific virus vaccine concepts and therapeutics.

  15. Comparison of E and NS1 antigens capture ELISA to detect dengue viral antigens from mosquitoes

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    Day-Yu Chao

    2015-01-01

    Interpretation & conclusion: With the future potential of antigen capture ELISA to be used in the resource deprived regions, the study showed that E-ELISA has similar sensitivity and antigen stability as NS1 Ag kit to complement the current established virological surveillance in human. The improvement of the sensitivity in detecting DENV-3/4 will be needed to incorporate this method into routine mosquito surveillance system.

  16. Uses of biosensors in the study of viral antigens.

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    Van Regenmortel, M H; Altschuh, D; Chatellier, J; Rauffer-Bruyère, N; Richalet-Sécordel, P; Saunal, H

    1997-01-01

    The introduction in 1990 of a new biosensor technology based on surface plasmon resonance has greatly simplified the measurement of binding interactions in biology. This new technology known as biomolecular interaction analysis makes it possible to visualize the binding process as a function of time by following the increase in refractive index that occurs when one of the interacting partners binds to its ligand immobilized on the surface of a sensor chip. None of the reactants needs to be labelled, which avoids the artefactual changes in binding properties that often result when the molecules are labelled. Biosensor instruments are well-suited for the rapid mapping of viral epitopes and for identifying which combinations of capturing and detector Mabs will give the best results in sandwich assays. Biosensor binding data are also useful for selecting peptides to be used in diagnostic solid-phase immunoassays. Very small changes in binding affinity can be measured with considerable precision which is a prerequisite for analyzing the functional effect and thermodynamic implications of limited structural changes in interacting molecules. On-rate (ka) and off-rate (kd) kinetic constants of the interaction between virus and antibody can be readily measured and the equilibrium affinity constant K can be calculated from the ratio ka/kd = K.

  17. Effect of BSA Antigen Sensitization during the Acute Phase of Influenza A Viral Infection on CD11c+ Pulmonary Antigen Presenting Cells

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    Fumitaka Sato

    2009-01-01

    Conclusions: BSA antigen sensitization during the acute phase of influenza A viral infection enhanced IL-10 production from naive CD4+ T cell interaction with CD11c+ pulmonary APCs. The IL-10 secretion evoked Th2 responses in the lungs with downregulation of Th1 responses and was important for the eosinophil recruitment into the lungs after BSA antigen challenge.

  18. Antigenic characterization of Brazilian bovine viral diarrhea virus isolates by monoclonal antibodies and cross-neutralization

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    Botton S.A.

    1998-01-01

    Full Text Available Nineteen Brazilian isolates of bovine viral diarrhea virus (BVDV were characterized antigenically with a panel of 19 monoclonal antibodies (mAbs (Corapi WV, Donis RO and Dubovi EJ (1990 American Journal of Veterinary Research, 55: 1388-1394. Eight isolates were further characterized by cross-neutralization using sheep monospecific antisera. Analysis of mAb binding to viral antigens by indirect immunofluorescence revealed distinct patterns of reactivity among the native viruses. Local isolates differed from the prototype Singer strain in recognition by up to 14 mAbs. Only two mAbs - one to the non-structural protein NS23/p125 and another to the envelope glycoprotein E0/gp48 - recognized 100% of the isolates. No isolate was recognized by more than 14 mAbs and twelve viruses reacted with 10 or less mAbs. mAbs to the major envelope glycoprotein E2/gp53 revealed a particularly high degree of antigenic variability in this glycoprotein. Nine isolates (47.3% reacted with three or less of 10 E2/gp53 mAbs, and one isolate was not recognized by any of these mAbs. Virus-specific antisera to eight isolates plus three standard BVDV strains raised in lambs had virus-neutralizing titers ranging from 400 to 3200 against the homologous virus. Nonetheless, many antisera showed significantly reduced neutralizing activity when tested against heterologous viruses. Up to 128-fold differences in cross-neutralization titers were observed for some pairs of viruses. When the coefficient of antigenic similarity (R was calculated, 49 of 66 comparisons (74.24% between viruses resulted in R values that antigenically distinguish strains. Moreover, one isolate had R values suggesting that it belongs to a distinct serologic group. The marked antigenic diversity observed among Brazilian BVDV isolates should be considered when planning diagnostic and immunization strategies.

  19. Viral Escape Mutant Epitope Maintains TCR Affinity for Antigen yet Curtails CD8 T Cell Responses.

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    Shayla K Shorter

    Full Text Available T cells have the remarkable ability to recognize antigen with great specificity and in turn mount an appropriate and robust immune response. Critical to this process is the initial T cell antigen recognition and subsequent signal transduction events. This antigen recognition can be modulated at the site of TCR interaction with peptide:major histocompatibility (pMHC or peptide interaction with the MHC molecule. Both events could have a range of effects on T cell fate. Though responses to antigens that bind sub-optimally to TCR, known as altered peptide ligands (APL, have been studied extensively, the impact of disrupting antigen binding to MHC has been highlighted to a lesser extent and is usually considered to result in complete loss of epitope recognition. Here we present a model of viral evasion from CD8 T cell immuno-surveillance by a lymphocytic choriomeningitis virus (LCMV escape mutant with an epitope for which TCR affinity for pMHC remains high but where the antigenic peptide binds sub optimally to MHC. Despite high TCR affinity for variant epitope, levels of interferon regulatory factor-4 (IRF4 are not sustained in response to the variant indicating differences in perceived TCR signal strength. The CD8+ T cell response to the variant epitope is characterized by early proliferation and up-regulation of activation markers. Interestingly, this response is not maintained and is characterized by a lack in IL-2 and IFNγ production, increased apoptosis and an abrogated glycolytic response. We show that disrupting the stability of peptide in MHC can effectively disrupt TCR signal strength despite unchanged affinity for TCR and can significantly impact the CD8+ T cell response to a viral escape mutant.

  20. Genetic and antigenic characterization of bovine viral diarrhea viruses isolated from cattle in Hokkaido, Japan.

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    Abe, Yuri; Tamura, Tomokazu; Torii, Shiho; Wakamori, Shiho; Nagai, Makoto; Mitsuhashi, Kazuya; Mine, Junki; Fujimoto, Yuri; Nagashima, Naofumi; Yoshino, Fumi; Sugita, Yukihiko; Nomura, Takushi; Okamatsu, Masatoshi; Kida, Hiroshi; Sakoda, Yoshihiro

    2016-01-01

    In our previous study, we genetically analyzed bovine viral diarrhea viruses (BVDVs) isolated from 2000 to 2006 in Japan and reported that subgenotype 1b viruses were predominant. In the present study, 766 BVDVs isolated from 2006 to 2014 in Hokkaido, Japan, were genetically analyzed to understand recent epidemics. Phylogenetic analysis based on nucleotide sequences of the 5'-untranslated region of viral genome revealed that 766 isolates were classified as genotype 1 (BVDV-1; 544 isolates) and genotype 2 (BVDV-2; 222). BVDV-1 isolates were further divided into BVDV-1a (93), 1b (371) and 1c (80) subgenotypes, and all BVDV-2 isolates were grouped into BVDV-2a subgenotype (222). Further comparative analysis was performed with BVDV-1a, 1b and 2a viruses isolated from 2001 to 2014. Phylogenetic analysis based on nucleotide sequences of the viral glycoprotein E2 gene, a major target of neutralizing antibodies, revealed that BVDV-1a, 1b and 2a isolates were further classified into several clusters. Cross-neutralization tests showed that BVDV-1b isolates were antigenically different from BVDV-1a isolates, and almost BVDV-1a, 1b and 2a isolates were antigenically similar among each subgenotype and each E2 cluster. Taken together, BVDV-1b viruses are still predominant, and BVDV-2a viruses have increased recently in Hokkaido, Japan. Field isolates of BVDV-1a, 1b and 2a show genetic diversity on the E2 gene with antigenic conservation among each subgenotype during the last 14 years.

  1. Human serum antibodies to a major defined epitope of human herpesvirus 8 small viral capsid antigen.

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    Tedeschi, R; De Paoli, P; Schulz, T F; Dillner, J

    1999-04-01

    The major antibody-reactive epitope of the small viral capsid antigen (sVCA) of human herpesvirus 8 (HHV-8) was defined by use of overlapping peptides. Strong IgG reactivity was found among approximately 50% of 44 human immunodeficiency virus-positive or -negative patients with Kaposi's sarcoma and 13 subjects who were seropositive by immunofluorescence assay (IFA) for the latent HHV-8 nuclear antigen. Only 1 of 106 subjects seronegative for both lytic and latent HHV-8 antigens and 10 of 81 subjects IFA-seropositive only for the lytic HHV-8 antigen had strong IgG reactivity to this epitope. Among 534 healthy Swedish women, only 1.3% were strongly seropositive. Comparison of the peptide-based and purified sVCA protein-based ELISAs found 55% sensitivity and 98% specificity. However, only 1 of 452 serum samples from healthy women was positive in both tests. In conclusion, the defined sVCA epitope was a specific, but not very sensitive, serologic marker of active HHV-8 infection. Such infection appears to be rare among Swedish women, even with sexual risk-taking behavior.

  2. Detection of Avian Antigen-Specific T Cells Induced by Viral Vaccines.

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    Dalgaard, Tina Sørensen; Norup, Liselotte Rothmann; Juul-Madsen, Helle Risdahl

    2016-01-01

    Live attenuated viral vaccines are widely used in commercial poultry production, but the development of new effective inactivated/subunit vaccines is needed. Studies of avian antigen-specific T cells are primarily based on analyses ex vivo after activating the cells with recall antigen. There is a particular interest in developing robust high-throughput assays as chicken vaccine trials usually comprise many individuals. In many respects, the avian immune system differs from the mammalian, and T cell assessment protocols must be adjusted accordingly to account for, e.g., differences in leukocyte subsets.The carboxyfluorescein succinimidyl ester (CFSE) method described in this chapter has been adapted to chicken cells. In this test, cells of interest are stained with CFSE. The succinimidyl ester group covalently binds to cellular amines forming fluorescent conjugates that are retained in the cells even throughout division. This leads to daughter cells containing half the fluorescence of their parents. When lymphocytes are loaded with CFSE prior to ex vivo stimulation with specific antigen, the measurement of serial halving of its fluorescence by flow cytometry identifies the cells responding to the stimulation. This method has been successfully applied to studies of chicken antigen-specific T cells.

  3. Identification, expression, and immunogenicity of Kaposi's sarcoma-associated herpesvirus-encoded small viral capsid antigen.

    Science.gov (United States)

    Lin, S F; Sun, R; Heston, L; Gradoville, L; Shedd, D; Haglund, K; Rigsby, M; Miller, G

    1997-04-01

    We describe a recombinant antigen for use in serologic tests for antibodies to Kaposi's sarcoma (KS)-associated herpesvirus (KSHV). The cDNA for a small viral capsid antigen (sVCA) was identified by immunoscreening of a library prepared from the BC-1 body cavity lymphoma cell line induced into KSHV lytic gene expression by sodium butyrate. The cDNA specified a 170-amino-acid peptide with homology to small viral capsid proteins encoded by the BFRF3 gene of Epstein-Barr virus and the ORF65 gene of herpesvirus saimiri. KSHV sVCA was expressed from a 0.85-kb mRNA present late in lytic KSHV replication in BC-1 cells. This transcript was sensitive to phosphonoacetic acid and phosphonoformic acid, inhibitors of herpesvirus DNA replication. KSHV sVCA expressed in mammalian cells or Escherichia coli or translated in vitro was recognized as an antigen by antisera from KS patients. Rabbit antisera raised to KSHV sVCA expressed in E. coli detected a 22-kDa protein in KSHV-infected human B cells. Overexpressed KSHV sVCA purified from E. coli and used as an antigen in immunoblot screening assay did not cross-react with EBV BFRF3. Antibodies to sVCA were present in 89% of 47 human immunodeficiency virus (HIV)-positive patients with KS, in 20% of 54 HIV-positive patients without KS, but in none of 122 other patients including children born to HIV-seropositive mothers and patients with hemophilia, autoimmune disease, or nasopharyngeal carcinoma. Low-titer antibody was detected in three sera from 28 healthy subjects. Antibodies to recombinant sVCA correlate with KS in high-risk populations. Recombinant sVCA can be used to examine the seroepidemiology of infection with KSHV in the general population.

  4. Treating cancer as an infectious disease--viral antigens as novel targets for treatment and potential prevention of tumors of viral etiology.

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    Xing Guo Wang

    Full Text Available BACKGROUND: Nearly 20% of human cancers worldwide have an infectious etiology with the most prominent examples being hepatitis B and C virus-associated hepatocellular carcinoma and human papilloma virus-associated cervical cancer. There is an urgent need to find new approaches to treatment and prevention of virus-associated cancers. METHODOLOGY/PRINCIPAL FINDINGS: Viral antigens have not been previously considered as targets for treatment or prevention of virus-associated cancers. We hypothesized that it was possible to treat experimental HPV16-associated cervical cancer (CC and Hepatitis B-associated hepatocellular carcinoma (HCC by targeting viral antigens expressed on cancer cells with radiolabeled antibodies to viral antigens. Treatment of experimental CC and HCC tumors with (188Re-labeled mAbs to E6 and HBx viral proteins, respectively, resulted in significant and dose-dependent retardation of tumor growth in comparison with untreated mice or mice treated with unlabeled antibodies. CONCLUSIONS/SIGNIFICANCE: This strategy is fundamentally different from the prior uses of radioimmunotherapy in oncology, which targeted tumor-associated human antigens and promises increased specificity and minimal toxicity of treatment. It also raises an exciting possibility to prevent virus-associated cancers in chronically infected patients by eliminating cells infected with oncogenic viruses before they transform into cancer.

  5. Antigenic variability in bovine viral diarrhea virus (BVDV) isolates from alpaca (Vicugna pacos), llama (Lama glama) and bovines in Chile.

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    Aguirre, I M; Quezada, M P; Celedón, M O

    2014-01-31

    Llamas and alpacas are domesticated South American camelids (SACs) important to ancestral population in the Altiplano region, and to different communities where they have been introduced worldwide. These ungulates have shown to be susceptible to several livestock viral pathogens such as members of the Pestivirus genus and mainly to bovine viral diarrhea virus (BVDV). Seventeen Chilean BVDV isolates were analyzed by serum cross neutralization with samples obtained from five llama, six alpacas, three bovines, plus three reference strains belonging to different subgroups and genotypes. The objective was to describe antigenic differences and similarities among them. Antigenic comparison showed significant differences between different subgroups. Consequently, antigenic similarities were observed among isolates belonging to the same subgroup and also between isolates from different animal species belonging the same subgroup. Among the analyzed samples, one pair of 1b subgroup isolates showed significant antigenic differences. On the other hand, one pair of isolates from different subgroups (1b and 1j) shared antigenic similarities indicating antigenic relatedness. This study shows for the first time the presence of antigenic differences within BVDV 1b subgroup and antigenic similarities within 1j subgroup isolates, demonstrating that genetic differences within BVDV subgroups do not necessary corresponds to differences on antigenicity.

  6. First report of Bovine Viral Diarrhea Virus antigen from pneumonic cattle in Sudan

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    Intisar Kamil Saeed

    2015-06-01

    Full Text Available To explore the expected role of Bovine Viral Diarrhea Virus (BVDV in pneumonia in cattle, cattle lungs (n=242 showing signs of pneumonia were collected from slaughter houses of three different localities located at Northern, Central and Western Sudan during 2010–2013. The collected samples were tested for the presence of BVDV antigen using Enzyme-Linked Immunosorbent Assay (ELISA, and Fluorescent Antibody Test (FAT. Twenty six (10.7% out of 242 samples were found to be positive for BVDV. Positive results were seen in all the three studied areas, with the highest prevalence (16.7%; n=4/24 at Gezira State in Central Sudan. BVDV genome could be detected in all ELISA positive samples. The results indicated the existence of BVDV infection in cattle in different areas in Sudan, and its possible association with respiratory infections in cattle. Analysis using BLAST indicated that the sequence was identical to the previously reported BVDV-1 (GenBank accession AF220247.1.; nucleotide A was found in our study at position 9 of our sequence, whereas T was present instead in the reference virus. This is the first report of detecting BVDV antigen, genome, and its sequence analysis collected from cattle lungs in Sudan.

  7. Chagasic patients are able to respond against a viral antigen from influenza virus

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    Lasso Paola

    2012-08-01

    Full Text Available Abstract Background Trypanosoma cruzi, the etiological agent of Chagas’ disease, is an obligate intracellular parasite which induces a CD8+ T cell immune response with secretion of cytokines and release of cytotoxic granules. Although an immune-suppressive effect of T. cruzi on the acute phase of the disease has been described, little is known about the capacity of CD8+ T cell from chronic chagasic patients to respond to a non-T. cruzi microbial antigen. Methods In the present paper, the frequency, phenotype and the functional activity of the CD8+ T cells specific from Flu-MP*, an influenza virus epitope, were determined in 13 chagasic patients and 5 healthy donors. Results The results show that Flu-MP* peptide specific CD8+ T cells were found with similar frequencies in both groups. In addition, Flu-MP* specific CD8+ T cells were distributed in the early or intermediate/late differentiation stages without showing enrichment of a specific sub-population. The mentioned Flu-MP* specific CD8+ T cells from chagasic patients were predominately TEM (CCR7- CD62L-, producing IL-2, IFNγ, CD107a/b and perforin, and did not present significant differences when compared with those from healthy donors. Conclusions Our results support the hypothesis that there is no CD8+ T cell nonspecific immune-suppression during chronic Chagas disease infection. Nonetheless, other viral antigens must be studied in order to confirm our findings.

  8. SIV antigen immunization induces transient antigen-specific T cell responses and selectively activates viral replication in draining lymph nodes in retroviral suppressed rhesus macaques

    Directory of Open Access Journals (Sweden)

    Barry Peter A

    2011-07-01

    Full Text Available Abstract Background HIV infection causes a qualitative and quantitative loss of CD4+ T cell immunity. The institution of anti-retroviral therapy (ART restores CD4+ T cell responses to many pathogens, but HIV-specific responses remain deficient. Similarly, therapeutic immunization with HIV antigens of chronically infected, ART treated subjects results in poor induction of HIV-specific CD4 responses. In this study, we used a macaque model of ART treatment during chronic infection to study the virologic consequences of SIV antigen stimulation in lymph nodes early after immunization. Rhesus CMV (RhCMV seropositive, Mamu A*01 positive rhesus macaques were chronically infected with SIVmac251 and treated with ART. The immune and viral responses to SIV gag and RhCMV pp65 antigen immunization in draining lymph nodes and peripheral blood were analyzed. Animals were immunized on contralateral sides with SIV gag and RhCMV pp65 encoding plasmids, which allowed lymph nodes draining each antigen to be obtained at the same time from the same animal for direct comparison. Results We observed that both SIV and RhCMV immunizations stimulated transient antigen-specific T cell responses in draining lymph nodes. The RhCMV-specific responses were potent and sustained (50 days post-immunization in the periphery, while the SIV-specific responses were transient and extinguished quickly. The SIV antigen stimulation selectively induced transient SIV replication in draining lymph nodes. Conclusions The data are consistent with a model whereby viral replication in response to SIV antigen stimulation limits the generation of SIV antigen-specific responses and suggests a potential mechanism for the early loss and poor HIV-specific CD4+ T cell response observed in HIV-infected individuals.

  9. Pelacakan Secara Imunohistokimiawi Antigen Virus pada Ayam yang Diinfeksi dengan Virus Penyakit Tetelo (IMMUNOHISTOCHEMICAL DETECTION OF VIRAL ANTIGEN IN TISSUE OF CHICKENS EXPERIMENTALLY INFECTED WITH NEWCASTLE DISEASE VIRUS

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    Anak Agung Ayu Mirah Adi

    2013-07-01

    Full Text Available In order to study the distribution of Newcastle disease virus (NDV following infection, chickenswere experimentally infected with visceretropic velogenic NDV isolate. Monoclonal antibodies (mAbsagainst the NDV LaSota vaccine strain were then produced to detect viral antigen in the infectedorgans. The mAbs were firstly tested for their specificity by enzyme linked immunosorbent assay(ELISA using NDV and normal allantoic fluids as antigens. Eight mAbs specific against NDVwere isolated and two mAbs were used for immunodetection of NDV antigen in chicken’s tissues.By immunohistochemistry labeled streptavidin-biotin (LSAB staining NDV–antigen was detectedin paraffin embedded tissues of NDV-infected chickens. NDV antigen was not detected in noninfected chickens. In the infected chickens, high intensity of NDV antigen was detected in thelymphoid tissues, lung and intestine. The NDV antigen with a lesser intensity was detected in thebrain, trachea, liver and myocardium. This study shows that although viscerotropic velogenicNDV isolate can infect almost all organs, the main target of infection are lung, intestine andlymphoids tissues

  10. Development of a sandwich Dot-ELISA for detecting bovine viral diarrhea virus antigen with E2 recombinant protein

    Institute of Scientific and Technical Information of China (English)

    Yuelan ZHAO; Yuzhu ZUO; Lei ZHANG; Jinghui FAN; Hanchun YANG; Jianhua QIN

    2009-01-01

    The IgG antibodies of rabbit anti-E2 protein of the bovine viral diarrhea virus were prepared by a general method from high efficiency serum immunized by E2 recombinant protein antigen expressed in E. coli prokaryotic expression system and were labeled to make enzymelabeled antibody with the method of NaIO4. A sandwich Dot enzyme-linked immunosorbent assay (Dot-ELISA) for the detection of BVDV was developed. The optimal reaction conditions of Dot-ELISAwere determined. The results show that optimal coating antibody was 300 μg·mL-1, the working concentration of HRP-labeled antibody was 1:50. The optimal blocking reagent and time were 5% bovine serum and 45 rain. The minimum detection of the content of antigen reached 1.35μg·mL-1. Compared with the routine IDEXX ELISA test kit with the whole virus, its specificity, sensitivity and coincidence rate were 90.48%, 96.55% and 95.24%, respectively. Compared with the sandwich Dot-ELISA with the negative staining electron microscope and RT-PCR, the coincidence rates were 90.9% and 93.1%, respectively. In addition, Bovine viral diarrhea virus (BVDV) antigen of 178 samples collected from cow farms in the Hebei Province, China, were detected by the developed Dot-ELISA and the IDEXX BVDV antigen Test Kit simultaneously, BVDV antigen positive rate was 39.89%-41.01%. The result of detecting clinical samples demonstrated that the established method showed its specificity, sensitivity and repeatability, whereas the results were easily interpreted without an ELISA reader.

  11. Localization of viral antigens in leaf protoplasts and plants by immunogold labelling.

    NARCIS (Netherlands)

    Lent, van J.W.M.

    1988-01-01

    This thesis describes the application of an immunocytochemical technique, immunogold labelling, new in the light and electron microscopic study of the plant viral infection. In Chapter 1 the present state of knowledge of the plant viral infection process, as revealed by insitu studies

  12. Understanding MHC class I presentation of viral antigens by human dendritic cells as a basis for rational design of therapeutic vaccines.

    Science.gov (United States)

    van Montfoort, Nadine; van der Aa, Evelyn; Woltman, Andrea M

    2014-01-01

    Effective viral clearance requires the induction of virus-specific CD8(+) cytotoxic T lymphocytes (CTL). Since dendritic cells (DC) have a central role in initiating and shaping virus-specific CTL responses, it is important to understand how DC initiate virus-specific CTL responses. Some viruses can directly infect DC, which theoretically allow direct presentation of viral antigens to CTL, but many viruses target other cells than DC and thus the host depends on the cross-presentation of viral antigens by DC to activate virus-specific CTL. Research in mouse models has highly enhanced our understanding of the mechanisms underlying cross-presentation and the dendritic cells (DC) subsets involved, however, these results cannot be readily translated toward the role of human DC in MHC class I-antigen presentation of human viruses. Here, we summarize the insights gained in the past 20 years on MHC class I presentation of viral antigen by human DC and add to the current debate on the capacities of different human DC subsets herein. Furthermore, possible sources of viral antigens and essential DC characteristics for effective induction of virus-specific CTL are evaluated. We conclude that cross-presentation is not only an efficient mechanism exploited by DC to initiate immunity to viruses that do not infect DC but also to viruses that do infect DC, because cross-presentation has many conceptual advantages and bypasses direct immune modulatory effects of the virus on its infected target cells. Since knowledge on the mechanism of viral antigen presentation and the preferred DC subsets is crucial for rational vaccine design, the obtained insights are very instrumental for the development of effective anti-viral immunotherapy.

  13. Understanding MHC class I presentation of viral antigens by human dendritic cells as a basis for rational design of therapeutic vaccines

    Directory of Open Access Journals (Sweden)

    Nadine eVan Montfoort

    2014-04-01

    Full Text Available Effective viral clearance requires the induction of virus-specific CD8+ cytotoxic T lymphocytes (CTL. Since dendritic cells (DC have a central role in initiating and shaping virus-specific CTL responses, it is important to understand how DC initiate virus-specific CTL responses. Some viruses can directly infect DC, which theoretically allows direct presentation of viral antigens to CTL, but many viruses target other cells than DC and thus the host depends on the cross-presentation of viral antigens by DC to activate virus-specific CTL.Research in mouse models has highly enhanced our understanding of the mechanisms underlying cross-presentation and the DC subsets involved, however, these results cannot be readily translated towards the role of human DC in MHC class I antigen presentation of human viruses. Here, we summarize the insights gained in the past 20 years on MHC class I presentation of viral antigen by human DC and add to the current debate on the capacities of different human DC subsets herein. Furthermore, possible sources of viral antigens and essential DC characteristics for effective induction of virus-specific CTL are evaluated.We conclude that cross-presentation is not only an efficient mechanism exploited by DC to initiate immunity to viruses that do not infect DC but also to viruses that do infect DC, because cross-presentation has many conceptual advantages and bypasses direct immune modulatory effects of the virus on its infected target cells. Since knowledge on the mechanism of viral antigen presentation and the preferred DC subsets is crucial for rational vaccine design, the obtained insights are very instrumental for the development of effective anti-viral immunotherapy.

  14. The herpes virus Fc receptor gE-gI mediates antibody bipolar bridging to clear viral antigens from the cell surface.

    Directory of Open Access Journals (Sweden)

    Blaise Ndjamen

    2014-03-01

    Full Text Available The Herpes Simplex Virus 1 (HSV-1 glycoprotein gE-gI is a transmembrane Fc receptor found on the surface of infected cells and virions that binds human immunoglobulin G (hIgG. gE-gI can also participate in antibody bipolar bridging (ABB, a process by which the antigen-binding fragments (Fabs of the IgG bind a viral antigen while the Fc binds to gE-gI. IgG Fc binds gE-gI at basic, but not acidic, pH, suggesting that IgG bound at extracellular pH by cell surface gE-gI would dissociate and be degraded in acidic endosomes/lysosomes if endocytosed. The fate of viral antigens associated with gE-gI-bound IgG had been unknown: they could remain at the cell surface or be endocytosed with IgG. Here, we developed an in vitro model system for ABB and investigated the trafficking of ABB complexes using 4-D confocal fluorescence imaging of ABB complexes with transferrin or epidermal growth factor, well-characterized intracellular trafficking markers. Our data showed that cells expressing gE-gI and the viral antigen HSV-1 gD endocytosed anti-gD IgG and gD in a gE-gI-dependent process, resulting in lysosomal localization. These results suggest that gE-gI can mediate clearance of infected cell surfaces of anti-viral host IgG and viral antigens to evade IgG-mediated responses, representing a general mechanism for viral Fc receptors in immune evasion and viral pathogenesis.

  15. Activated human nasal epithelial cells modulate specific antibody response against bacterial or viral antigens.

    Directory of Open Access Journals (Sweden)

    Chiou-Yueh Yeh

    Full Text Available Nasal mucosa is an immune responsive organ evidenced by eliciting both specific local secretory IgA and systemic IgG antibody responses with intra-nasal administration of antigens. Nevertheless, the role of nasal epithelial cells in modulating such responses is unclear. Human nasal epithelial cells (hNECs obtained from sinus mucosa of patients with chronic rhinosinusitis were cultured in vitro and firstly were stimulated by Lactococcus lactis bacterium-like particles (BLPs in order to examine their role on antibody production. Secondly, both antigens of immunodominant protein IDG60 from oral Streptococcus mutans and hemagglutinin (HA from influenza virus were tested to evaluate the specific antibody response. Stimulated hNECs by BLPs exhibited a significant increase in the production of interleukin-6 (IL-6, and thymic stromal lymphopoietin (TSLP. Conditioned medium of stimulated hNECs has effects on enhancing the proliferation of CD4+ T cells together with interferon-γ and IL-5 production, increasing the costimulatory molecules on dendritic cells and augmenting the production of IDG60 specific IgA, HA specific IgG, IgA by human peripheral blood lymphocytes. Such production of antigen specific IgG and IgA is significantly counteracted in the presence of IL-6 and TSLP neutralizing antibodies. In conclusion, properly stimulated hNECs may impart immuno-modulatory effects on the antigen-specific antibody response at least through the production of IL-6 and TSLP.

  16. Going viral: chimeric antigen receptor T-cell therapy for hematological malignancies.

    Science.gov (United States)

    Gill, Saar; June, Carl H

    2015-01-01

    On July 1, 2014, the United States Food and Drug Administration granted 'breakthrough therapy' designation to CTL019, the anti-CD19 chimeric antigen receptor T-cell therapy developed at the University of Pennsylvania. This is the first personalized cellular therapy for cancer to be so designated and occurred 25 years after the first publication describing genetic redirection of T cells to a surface antigen of choice. The peer-reviewed literature currently contains the outcomes of more than 100 patients treated on clinical trials of anti-CD19 redirected T cells, and preliminary results on many more patients have been presented. At last count almost 30 clinical trials targeting CD19 were actively recruiting patients in North America, Europe, and Asia. Patients with high-risk B-cell malignancies therefore represent the first beneficiaries of an exciting and potent new treatment modality that harnesses the power of the immune system as never before. A handful of trials are targeting non-CD19 hematological and solid malignancies and represent the vanguard of enormous preclinical efforts to develop CAR T-cell therapy beyond B-cell malignancies. In this review, we explain the concept of chimeric antigen receptor gene-modified T cells, describe the extant results in hematologic malignancies, and share our outlook on where this modality is likely to head in the near future.

  17. Enhanced expression of HIV and SIV vaccine antigens in the structural gene region of live attenuated rubella viral vectors and their incorporation into virions.

    Science.gov (United States)

    Virnik, Konstantin; Ni, Yisheng; Berkower, Ira

    2013-04-19

    Despite the urgent need for an HIV vaccine, its development has been hindered by virus variability, weak immunogenicity of conserved epitopes, and limited durability of the immune response. For other viruses, difficulties with immunogenicity were overcome by developing live attenuated vaccine strains. However, there is no reliable method of attenuation for HIV, and an attenuated strain would risk reversion to wild type. We have developed rubella viral vectors, based on the live attenuated vaccine strain RA27/3, which are capable of expressing important HIV and SIV vaccine antigens. The rubella vaccine strain has demonstrated safety, immunogenicity, and long lasting protection in millions of children. Rubella vectors combine the growth and immunogenicity of live rubella vaccine with the antigenicity of HIV or SIV inserts. This is the first report showing that live attenuated rubella vectors can stably express HIV and SIV vaccine antigens at an insertion site located within the structural gene region. Unlike the Not I site described previously, the new site accommodates a broader range of vaccine antigens without interfering with essential viral functions. In addition, antigens expressed at the structural site were controlled by the strong subgenomic promoter, resulting in higher levels and longer duration of antigen expression. The inserts were expressed as part of the structural polyprotein, processed to free antigen, and incorporated into rubella virions. The rubella vaccine strain readily infects rhesus macaques, and these animals will be the model of choice for testing vector growth in vivo and immunogenicity.

  18. Priming Cross-Protective Bovine Viral Diarrhea Virus-Specific Immunity Using Live-Vectored Mosaic Antigens

    Science.gov (United States)

    Fang, Xin; Waghela, Suryakant D.; Bray, Jocelyn; Njongmeta, Leo M.; Herring, Andy; Abdelsalam, Karim W.; Chase, Christopher; Mwangi, Waithaka

    2017-01-01

    Bovine viral diarrhea virus (BVDV) plays a key role in bovine respiratory disease complex, which can lead to pneumonia, diarrhea and death of calves. Current vaccines are not very effective due, in part, to immunosuppressive traits and failure to induce broad protection. There are diverse BVDV strains and thus, current vaccines contain representative genotype 1 and 2 viruses (BVDV-1 & 2) to broaden coverage. BVDV modified live virus (MLV) vaccines are superior to killed virus vaccines, but they are susceptible to neutralization and complement-mediated destruction triggered by passively acquired antibodies, thus limiting their efficacy. We generated three novel mosaic polypeptide chimeras, designated NproE2123; NS231; and NS232, which incorporate protective determinants that are highly conserved among BVDV-1a, 1b, and BVDV-2 genotypes. In addition, strain-specific protective antigens from disparate BVDV strains were included to broaden coverage. We confirmed that adenovirus constructs expressing these antigens were strongly recognized by monoclonal antibodies, polyclonal sera, and IFN-γ-secreting T cells generated against diverse BVDV strains. In a proof-of-concept efficacy study, the multi-antigen proto-type vaccine induced higher, but not significantly different, IFN-γ spot forming cells and T-cell proliferation compared to a commercial MLV vaccine. In regards to the humoral response, the prototype vaccine induced higher BVDV-1 specific neutralizing antibody titers, whereas the MLV vaccine induced higher BVDV-2 specific neutralizing antibody titers. Following BVDV type 2a (1373) challenge, calves immunized with the proto-type or the MLV vaccine had lower clinical scores compared to naïve controls. These results support the hypothesis that a broadly protective subunit vaccine can be generated using mosaic polypeptides that incorporate rationally selected and validated protective determinants from diverse BVDV strains. Furthermore, regarding biosafety of using a

  19. Psoralen Inactivation of Viruses: A Process for the Safe Manipulation of Viral Antigen and Nucleic Acid

    Directory of Open Access Journals (Sweden)

    Katherine Schneider

    2015-11-01

    Full Text Available High consequence human pathogenic viruses must be handled at biosafety level 2, 3 or 4 and must be rendered non-infectious before they can be utilized for molecular or immunological applications at lower biosafety levels. Here we evaluate psoralen-inactivated Arena-, Bunya-, Corona-, Filo-, Flavi- and Orthomyxoviruses for their suitability as antigen in immunological processes and as template for reverse transcription PCR and sequencing. The method of virus inactivation using a psoralen molecule appears to have broad applicability to RNA viruses and to leave both the particle and RNA of the treated virus intact, while rendering the virus non-infectious.

  20. A novel multi-antigen virally vectored vaccine against Mycobacterium avium subspecies paratuberculosis.

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    Tim J Bull

    Full Text Available BACKGROUND: Mycobacterium avium subspecies paratuberculosis causes systemic infection and chronic intestinal inflammation in many species including primates. Humans are exposed through milk and from sources of environmental contamination. Hitherto, the only vaccines available against Mycobacterium avium subspecies paratuberculosis have been limited to veterinary use and comprised attenuated or killed organisms. METHODS: We developed a vaccine comprising a fusion construct designated HAV, containing components of two secreted and two cell surface Mycobacterium avium subspecies paratuberculosis proteins. HAV was transformed into DNA, human Adenovirus 5 (Ad5 and Modified Vaccinia Ankara (MVA delivery vectors. Full length expression of the predicted 95 kDa fusion protein was confirmed. PRINCIPAL FINDINGS: Vaccination of naïve and Mycobacterium avium subspecies paratuberculosis infected C57BL/6 mice using DNA-prime/MVA-boost or Ad5-prime/MVA-boost protocols was highly immunogenic resulting in significant IFN-gamma ELISPOT responses by splenocytes against recombinant vaccine antigens and a range of HAV specific peptides. This included strong recognition of a T-cell epitope GFAEINPIA located near the C-terminus of the fusion protein. Antibody responses to recombinant vaccine antigens and HAV specific peptides but not GFAEINPIA, also occurred. No immune recognition of vaccine antigens occurred in any sham vaccinated Mycobacterium avium subspecies paratuberculosis infected mice. Vaccination using either protocol significantly attenuated pre-existing Mycobacterium avium subspecies paratuberculosis infection measured by qPCR in spleen and liver and the Ad5-prime/MVA-boost protocol also conferred some protection against subsequent challenge. No adverse effects of vaccination occurred in any of the mice. CONCLUSIONS/SIGNIFICANCE: A range of modern veterinary and clinical vaccines for the treatment and prevention of disease caused by Mycobacterium avium

  1. Role of very late antigen-1 in T-cell-mediated immunity to systemic viral infection

    DEFF Research Database (Denmark)

    Ørding Kauffmann, Susanne; Thomsen, Allan Randrup; Christensen, Jan Pravsgaard

    2006-01-01

    The T-cell response to lymphocytic choriomeningitis virus was studied in mice lacking very late antigen-1 (VLA-1). The generation of virus-specific effector T cells was unimpaired in VLA-1(-/-) mice. In the memory phase, VLA-1 deficiency did not influence the number of memory CD8(+) T cells or th......, the current findings indicate that the expression of VLA-1 is not pivotal for T-cell-mediated antiviral immunity to a systemic infection.......-cell-mediated inflammation, no significant influence of VLA-1 was found either in the primary response or in the memory phase. However, alpha-VLA-4 antibody reduced the DTH-like reaction in VLA-1(-/-) mice to a higher degree than in wt mice, suggesting a synergistic effect of blocking both integrins. Taken together...

  2. Human hepatitis B viral e antigen and its precursor P20 inhibit T lymphocyte proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Purvina, Maija; Hoste, Astrid; Rossignol, Jean-Michel [Universite de Versailles-Saint-Quentin-en-Yvelines, Laboratoire de Genetique et Biologie Cellulaire, EA 4589, 45 avenue des Etats-Unis, 78035 Versailles (France); Lagaudriere-Gesbert, Cecile, E-mail: cecile.lagaudriere-gesbert@u-psud.fr [Universite de Versailles-Saint-Quentin-en-Yvelines, Laboratoire de Genetique et Biologie Cellulaire, EA 4589, 45 avenue des Etats-Unis, 78035 Versailles (France)

    2012-01-27

    Highlights: Black-Right-Pointing-Pointer P20, precursor of the HBeAg, interacts with the cellular protein gC1qR. Black-Right-Pointing-Pointer HBeAg and P20 bind to T cell surface and inhibit mitogen-induced T cell division. Black-Right-Pointing-Pointer HBeAg and P20 inhibition of T cell proliferation is gC1qR and IL-1RAcP-independent. -- Abstract: The hepatitis B virus (HBV) Precore protein is processed through the secretory pathway directly as HBeAg or with the generation of an intermediate (P20). Precore gene has been shown to be implicated in viral persistence, but the functions of HBeAg and its precursors have not been fully elucidated. We show that the secreted proteins HBeAg and P20 interact with T cell surface and alter Kit-225 and primary T cells proliferation, a process which may facilitate the establishment of HBV persistence. Our data indicate that the N-terminal end of Precore is important for these inhibitory effects and exclude that they are dependent on the association of HBeAg and P20 with two characterized cell surface ligands, the Interleukin-1 Receptor Accessory Protein and gC1qR (present study).

  3. Cost-Effectiveness of Testing Hepatitis B–Positive Pregnant Women for Hepatitis B e Antigen or Viral Load

    Science.gov (United States)

    Fan, Lin; Owusu-Edusei, Kwame; Schillie, Sarah F.; Murphy, Trudy V.

    2015-01-01

    OBJECTIVE To estimate the cost-effectiveness of testing pregnant women with hepatitis B (hepatitis B surface antigen [HBsAg]-positive) for hepatitis B e antigen (HBeAg) or hepatitis B virus (HBV) DNA, and administering maternal antiviral prophylaxis if indicated, to decrease breakthrough perinatal HBV transmission from the U.S. health care perspective. METHODS A Markov decision model was constructed for a 2010 birth cohort of 4 million neonates to estimate the cost-effectiveness of two strategies: testing HBsAg-positive pregnant women for 1) HBeAg or 2) HBV load. Maternal antiviral prophylaxis is given from 28 weeks of gestation through 4 weeks postpartum when HBeAg is positive or HBV load is high (108 copies/mL or greater). These strategies were compared with the current recommendation. All neonates born to HBsAg-positive women received recommended active-passive immunoprophylaxis. Effects were measured in quality-adjusted life-years (QALYs) and all costs were in 2010 U.S. dollars. RESULTS The HBeAg testing strategy saved $3.3 million and 3,080 QALYs and prevented 486 chronic HBV infections compared with the current recommendation. The HBV load testing strategy cost $3 million more than current recommendation, saved 2,080 QALYs, and prevented 324 chronic infections with an incremental cost-effectiveness ratio of $1,583 per QALY saved compared with the current recommendations. The results remained robust over a wide range of assumptions. CONCLUSION Testing HBsAg-positive pregnant women for HBeAg or HBV load followed by maternal antiviral prophylaxis if HBeAg-positive or high viral load to reduce perinatal hepatitis B transmission in the United States is cost-effective. PMID:24785842

  4. Effects of hepatitis B virus precore and basal core promoter mutations on the expression of viral antigens: genotype B vs C.

    Science.gov (United States)

    Liu, C-J; Cheng, H-R; Chen, C-L; Chen, T-C; Tseng, T-C; Wang, Z-L; Chen, P-J; Liu, C-H; Chen, D-S; Kao, J-H

    2011-10-01

    Hepatitis B virus (HBV) genotypes/mutants are known to affect natural outcomes. The virologic differences among HBV genotype, precore and basal core promoter (BCP) mutations were investigated. HBV strains were isolated from 18 hepatitis B e antigen (HBeAg)-positive patients (nine genotype B and nine genotype C). All had precore and BCP wild-type sequences. After cloning of full-length HBV genome, the effects of viral genotype, precore and BCP mutations singly or additively on the expression of viral DNA and antigens were investigated by mutagenesis and transfection assays in Huh7 cells. Significant findings included the following: (i) expression of intracellular core protein increased when precore or BCP mutation was introduced in genotype C strains; (ii) expression of intracellular surface protein was lower in genotype C precore wild-type strain compared with genotype B; (iii) precore mutation was associated with a lower extracellular expression level of HBV DNA; (iv) secretion of hepatitis B surface antigen in genotype C was lower than that in genotype B; and (v) secretion of HBeAg in genotype B was lower than that in genotype C. No additive effect was observed by combining precore and BCP mutations. Hence, HBV genotype and precore/BCP mutations correlate with intrahepatic expression of viral antigens in vitro.

  5. Human platelets antigens influence the viral load of platelets after the interaction of the platelets with HCV and HIV in vitro

    Directory of Open Access Journals (Sweden)

    Rejane Maria Tommasini Grotto

    Full Text Available Abstract: INTRODUCTION: In this study, we evaluated hepatitis C virus (HCV and human immunodeficiency virus (HIV - platelet interactions in vitro as well as human platelets antigen (HPA polymorphisms. METHODS: Platelets were obtained from 100 healthy HPA-genotyped volunteer donors and incubated with HIV or HCV. The viral load after in vitro exposure was detected. RESULTS: The viral load in the platelets after exposure to the virus was higher in the HIV exposure than in the HCV exposure. CONCLUSIONS: HIV-platelet ligation could be more efficient than HCV-platelet interaction. Further, the HPA-1b allele seems to influence the interaction of platelets with HCV.

  6. [Diagnostico-prognostic significance of the analysis of anti-HIV antibodies and viral antigens in acquired immunodeficiency syndrome. Presentation of 2 paradigmatic cases].

    Science.gov (United States)

    Venturini, L; Serpelloni, G; Parolin, A; Mezzelani, P

    1989-05-01

    The authors, after reviewing the current literature about the serological pattern of anti-HIV antibodies detected with Western Blot and the research of the viral antigen in AIDS, report the study of the above mentioned parameters in two HIV seropositive drug addicts. Case 1 (symptomless seropositive) presented a reactivity against p24 and p55 a month after an acute HIV infection and a more delayed reactivity to the whole anti-HIV antibody pattern. Case 2 (which developed full-blown AIDS), together with clinical and immunological deterioration, had a decline and disappearance of antibodies to p24 and persistence of reactivity against gp41 and detection of viral antigen. Diagnostic and prognostic significance of these results are discussed.

  7. Cloning of the Rhesus Lymphocryptovirus Viral Capsid Antigen and Epstein-Barr Virus-Encoded Small RNA Homologues and Use in Diagnosis of Acute and Persistent Infections

    OpenAIRE

    Rao, Pasupuleti; Jiang, Hua; Wang, Fred

    2000-01-01

    Epstein-Barr virus (EBV) is the most common cause of infectious mononucleosis and is associated with the development of several human malignancies. A closely related herpesvirus in the same lymphocryptovirus (LCV) genera as EBV naturally infects rhesus monkeys and provides an important animal model for studying EBV pathogenesis. We cloned the small viral capsid antigen (sVCA) homologue from the rhesus LCV and developed a peptide enzyme-linked immunosorbent assay (ELISA) to determine whether e...

  8. A viral vectored prime-boost immunization regime targeting the malaria Pfs25 antigen induces transmission-blocking activity.

    Directory of Open Access Journals (Sweden)

    Anna L Goodman

    Full Text Available The ookinete surface protein Pfs25 is a macrogamete-to-ookinete/ookinete stage antigen of Plasmodium falciparum, capable of exerting high-level anti-malarial transmission-blocking activity following immunization with recombinant protein-in-adjuvant formulations. Here, this antigen was expressed in recombinant chimpanzee adenovirus 63 (ChAd63, human adenovirus serotype 5 (AdHu5 and modified vaccinia virus Ankara (MVA viral vectored vaccines. Two immunizations were administered to mice in a heterologous prime-boost regime. Immunization of mice with AdHu5 Pfs25 at week 0 and MVA Pfs25 at week 10 (Ad-MVA Pfs25 resulted in high anti-Pfs25 IgG titers, consisting of predominantly isotypes IgG1 and IgG2a. A single priming immunization with ChAd63 Pfs25 was as effective as AdHu5 Pfs25 with respect to ELISA titers at 8 weeks post-immunization. Sera from Ad-MVA Pfs25 immunized mice inhibited the transmission of P. falciparum to the mosquito both ex vivo and in vivo. In a standard membrane-feeding assay using NF54 strain P. falciparum, oocyst intensity in Anopheles stephensi mosquitoes was significantly reduced in an IgG concentration-dependent manner when compared to control feeds (96% reduction of intensity, 78% reduction in prevalence at a 1 in 5 dilution of sera. In addition, an in vivo transmission-blocking effect was also demonstrated by direct feeding of immunized mice infected with Pfs25DR3, a chimeric P. berghei line expressing Pfs25 in place of endogenous Pbs25. In this assay the density of Pfs25DR3 oocysts was significantly reduced when mosquitoes were fed on vaccinated as compared to control mice (67% reduction of intensity, 28% reduction in prevalence and specific IgG titer correlated with efficacy. These data confirm the utility of the adenovirus-MVA vaccine platform for the induction of antibodies with transmission-blocking activity, and support the continued development of this alternative approach to transmission-blocking malaria subunit

  9. Combination of autoantibodies against NY-ESO-1 and viral capsid antigen immunoglobulin A for improved detection of nasopharyngeal carcinoma.

    Science.gov (United States)

    Peng, Yu-Hui; Xu, Yi-Wei; Qiu, Si-Qi; Hong, Chao-Qun; Zhai, Tian-Tian; Li, En-Min; Xu, Li-Yan

    2014-09-01

    Nasopharyngeal carcinoma (NPC) is one of the most common malignant tumors in Southern China and Southeast Asia, and early detection remains a challenge. Autoantibodies have been found to precede the manifestations of symptomatic cancer by several months to years, making their identification of particular relevance for early detection. In the present study, the diagnostic value of serum autoantibodies against NY-ESO-1 in NPC patients was evaluated. The study included 112 patients with NPC and 138 normal controls. Serum levels of autoantibodies against NY-ESO-1 and classical Epstein-Barr virus marker, viral capsid antigen immunoglobulin A (VCA-IgA), were measured by enzyme-linked immunosorbent assay. Measurement of autoantibodies against NY-ESO-1 and VCA-IgA demonstrated a sensitivity/specificity of 42.9/94.9% [95% confidence interval (CI), 33.7-52.6/89.4-97.8%] and 55.4/95.7% (95% CI, 45.7-64.7/90.4-98.2%), respectively. The area under receiver operating characteristic curve for autoantibodies against NY-ESO-1 (0.821; 95% CI, 0.771-0.871) was marginally lower than that for VCA-IgA (0.860; 95% CI, 0.810-0.910) in NPC. The combination of autoantibodies against NY-ESO-1 and VCA-IgA yielded an enhanced sensitivity of 80.4% (95% CI, 71.6-87.0%) and a specificity of 90.6% (95% CI, 84.1-94.7%). Moreover, detection of autoantibodies against NY-ESO-1 could differentiate early-stage NPC patients from normal controls. Our results suggest that autoantibodies against NY-ESO-1 may serve as a potential biomarker, as a supplement to VCA-IgA, for the screening and diagnosis of NPC.

  10. Lesions and distribution of viral antigen following an experimental infection of young seronegative calves with virulent bovine virus diarrhea virus-type II.

    Science.gov (United States)

    Ellis, J A; West, K H; Cortese, V S; Myers, S L; Carman, S; Martin, K M; Haines, D M

    1998-07-01

    During the past several years, acute infections with bovine viral diarrhea virus (BVDV) have been causally linked to hemorrhagic and acute mucosal disease-like syndromes with high mortality. The majority of BVDVs isolated in such cases have been classified as type II on the basis of genetic and antigenic characteristics. It was our objective to examine clinical disease, lesions and potential sites of viral replication, following experimental BVDV type II infection in young calves. On approximately day 35 after birth, calves that had received BVDV-antibody-negative colostrum were infected by intranasal inoculation of 5 x 10(5) TCID50 of BVDV type II isolate 24,515 in 5 mL of tissue culture fluid (2.5 mL/nostril). Calves were monitored twice daily for signs of clinical disease. Approximately 48-72 h after infection, all calves developed transient pyrexia (39.4-40.5 degrees C) and leukopenia. Beginning on approximately day 7 after infection, all calves developed watery diarrhea, pyrexia (40.5-41.6 degrees C), marked leukopenia (> or = 75% drop from preinoculation values), variable thrombocytopenia, and moderate to severe depression. Calves were euthanized on days 10, 11, or 12 after infection due to severe disease. Gross and histological lesions consisted of multifocal bronchointerstitial pneumonia (involving 10%-25% of affected lungs), bone marrow hypoplasia and necrosis, and minimal erosive lesions in the alimentary tract. Immunohistochemical staining for BVDV revealed widespread viral antigen usually within epithelial cells, smooth muscle cells and mononuclear phagocytes in multiple organs, including lung, Peyer's patches, gastric mucosa, thymus, adrenal gland, spleen, lymph nodes, bone marrow, and skin. This BVDV type II isolate caused rapidly progressive, severe multisystemic disease in seronegative calves that was associated with widespread distribution of viral antigen and few gross or histological inflammatory lesions.

  11. Clinical evaluation of a new enzyme immunoassay for hepatitis B virus core-related antigen; a marker distinct from viral DNA for monitoring lamivudine treatment.

    Science.gov (United States)

    Rokuhara, A; Tanaka, E; Matsumoto, A; Kimura, T; Yamaura, T; Orii, K; Sun, X; Yagi, S; Maki, N; Kiyosawa, K

    2003-07-01

    We aimed to assess the clinical performance of a newly developed chemiluminescence enzyme immunoassay (CLEIA) for the detection of hepatitis B virus (HBV) core-related antigen (HBcrAg) in patients with chronic HBV infection. A total of 82 patients with chronic HBV infection and 167 HBV-negative controls were studied. HBcrAg was measured by CLEIA with monoclonal antibodies to hepatitis B e antigen (HBeAg) and hepatitis B core antigen (HBcAg), and HBV DNA was measured by transcription-mediated amplification assay (TMA) and in-house real-time detection polymerase chain reaction (RTD-PCR). The HBcrAg assay detected viremia in 189 of 216 samples (88%) collected from 72 patients whilst the TMA assay detected viremia in 178 of the 216 samples (82%) (P = 0.019). The HBcrAg concentration correlated linearly with the HBV DNA concentration (P HBcrAg assay was not affected by the absence of hepatitis B e antigen from the serum or the presence of precore mutations in the HBV genome. In patients without anti-viral drugs, changes in their serum HBcrAg concentration over time corresponded to their HBV DNA concentration. In six additional patients who were later treated with lamivudine, HBV DNA concentration declined more rapidly than their HBcrAg concentration. Three months after treatment commenced, the ratio of HBcrAg: HBV DNA had increased in all six patients (P = 0.031). The HBcrAg assay is a sensitive and useful test for the assessment of a patient's HBV load. When monitoring the anti-viral effect of lamivudine, HBcrAg provides a viral marker which is independent of HBV DNA.

  12. A mimotope of Pre-S2 region of surface antigen of viral hepatitis Bscreened by phage display

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    To acquire the phage-displayed mimotopes which mimic the specificity of hepatitis B virus surface antigen (HBsAg), a random peptide library expressing linear peptide with 12 amino acids in length were used to screen with the serum from a hepatitis B virus infected patient in the recovery phase. After 3 rounds of biopanning, the positive phages were confirmed by competitive ELISA using HBsAg/P33. Two phagotopes were identified and one of them was confirmed as mimotope by competition experiment. Based on the mimotpe, a multiple antigenic peptide with four branches was synthesized by solid phase peptide synthesis. The antiginicity and specificity of the synthesized antigen was tested in BALB/c mice compared with the native epitope-based antigen. The results showed that the mimotope-based antigen could evoke higher titer of antibodies with the same specificity of the epitope-based antigen. Those findings indicate mimotopes can be used in antigen and vaccine design.

  13. Analysis of precore/core covariances associated with viral kinetics and genotypes in hepatitis B e antigen-positive chronic hepatitis B patients.

    Directory of Open Access Journals (Sweden)

    Chun-Pei Cheng

    Full Text Available Hepatitis B virus (HBV is one of the most common DNA viruses that can cause aggressive hepatitis, cirrhosis and hepatocellular carcinoma. Although many people are persistently infected with HBV, the kinetics in serum levels of viral loads and the host immune responses vary from person to person. HBV precore/core open reading frame (ORF encoding proteins, hepatitis B e antigen (HBeAg and core antigen (HBcAg, are two indicators of active viral replication. The aim of this study was to discover a variety of amino acid covariances in responses to viral kinetics, seroconversion and genotypes during the course of HBV infection. A one year follow-up study was conducted with a total number of 1,694 clones from 23 HBeAg-positive chronic hepatitis B patients. Serum alanine aminotransferase, HBV DNA and HBeAg levels were measured monthly as criteria for clustering patients into several different subgroups. Monthly derived multiple precore/core ORFs were directly sequenced and translated into amino acid sequences. For each subgroup, time-dependent covariances were identified from their time-varying sequences over the entire follow-up period. The fluctuating, wavering, HBeAg-nonseroconversion and genotype C subgroups showed greater degrees of covariances than the stationary, declining, HBeAg-seroconversion and genotype B. Referring to literature, mutation hotspots within our identified covariances were associated with the infection process. Remarkably, hotspots were predominant in genotype C. Moreover, covariances were also identified at early stage (spanning from baseline to a peak of serum HBV DNA in order to determine the intersections with aforementioned time-dependent covariances. Preserved covariances, namely representative covariances, of each subgroup are visually presented using a tree-based structure. Our results suggested that identified covariances were strongly associated with viral kinetics, seroconversion and genotypes. Moreover

  14. Expression of VP7, a Bluetongue virus group specific antigen by viral vectors: analysis of the induced immune responses and evaluation of protective potential in sheep.

    Directory of Open Access Journals (Sweden)

    Coraline Bouet-Cararo

    Full Text Available Bluetongue virus (BTV is an economically important Orbivirus transmitted by biting midges to domestic and wild ruminants. The need for new vaccines has been highlighted by the occurrence of repeated outbreaks caused by different BTV serotypes since 1998. The major group-reactive antigen of BTV, VP7, is conserved in the 26 serotypes described so far, and its role in the induction of protective immunity has been proposed. Viral-based vectors as antigen delivery systems display considerable promise as veterinary vaccine candidates. In this paper we have evaluated the capacity of the BTV-2 serotype VP7 core protein expressed by either a non-replicative canine adenovirus type 2 (Cav-VP7 R0 or a leporipoxvirus (SG33-VP7, to induce immune responses in sheep. Humoral responses were elicited against VP7 in almost all animals that received the recombinant vectors. Both Cav-VP7 R0 and SG33-VP7 stimulated an antigen-specific CD4+ response and Cav-VP7 R0 stimulated substantial proliferation of antigen-specific CD8+ lymphocytes. Encouraged by the results obtained with the Cav-VP7 R0 vaccine vector, immunized animals were challenged with either the homologous BTV-2 or the heterologous BTV-8 serotype and viral burden in plasma was followed by real-time RT-PCR. The immune responses triggered by Cav-VP7 R0 were insufficient to afford protective immunity against BTV infection, despite partial protection obtained against homologous challenge. This work underscores the need to further characterize the role of BTV proteins in cross-protective immunity.

  15. Expression of VP7, a Bluetongue Virus Group Specific Antigen by Viral Vectors: Analysis of the Induced Immune Responses and Evaluation of Protective Potential in Sheep

    Science.gov (United States)

    Bouet-Cararo, Coraline; Contreras, Vanessa; Caruso, Agathe; Top, Sokunthea; Szelechowski, Marion; Bergeron, Corinne; Viarouge, Cyril; Desprat, Alexandra; Relmy, Anthony; Guibert, Jean-Michel; Dubois, Eric; Thiery, Richard; Bréard, Emmanuel; Bertagnoli, Stephane; Richardson, Jennifer; Foucras, Gilles; Meyer, Gilles; Schwartz-Cornil, Isabelle; Zientara, Stephan; Klonjkowski, Bernard

    2014-01-01

    Bluetongue virus (BTV) is an economically important Orbivirus transmitted by biting midges to domestic and wild ruminants. The need for new vaccines has been highlighted by the occurrence of repeated outbreaks caused by different BTV serotypes since 1998. The major group-reactive antigen of BTV, VP7, is conserved in the 26 serotypes described so far, and its role in the induction of protective immunity has been proposed. Viral-based vectors as antigen delivery systems display considerable promise as veterinary vaccine candidates. In this paper we have evaluated the capacity of the BTV-2 serotype VP7 core protein expressed by either a non-replicative canine adenovirus type 2 (Cav-VP7 R0) or a leporipoxvirus (SG33-VP7), to induce immune responses in sheep. Humoral responses were elicited against VP7 in almost all animals that received the recombinant vectors. Both Cav-VP7 R0 and SG33-VP7 stimulated an antigen-specific CD4+ response and Cav-VP7 R0 stimulated substantial proliferation of antigen-specific CD8+ lymphocytes. Encouraged by the results obtained with the Cav-VP7 R0 vaccine vector, immunized animals were challenged with either the homologous BTV-2 or the heterologous BTV-8 serotype and viral burden in plasma was followed by real-time RT-PCR. The immune responses triggered by Cav-VP7 R0 were insufficient to afford protective immunity against BTV infection, despite partial protection obtained against homologous challenge. This work underscores the need to further characterize the role of BTV proteins in cross-protective immunity. PMID:25364822

  16. High Programmed Death-1 levels on HCV specific T cells during acute infection are associated with viral persistence and require preservation of cognate antigen during chronic infection1

    Science.gov (United States)

    Rutebemberwa, Alleluiah; Ray, Stuart C.; Astemborski, Jacquie; Levine, Jordana; Liu, Lin; Dowd, Kimberly A.; Clute, Shalyn; Wang, Changyu; Korman, Alan; Sette, Alessandro; Sidney, John; Pardoll, Drew M.; Cox, Andrea L.

    2009-01-01

    HCV is an important human pathogen that represents a model for chronic infection since the majority of infected individuals fail to clear the infection despite generation of virus-specific T cell responses during the period of acute infection. While viral sequence evolution at targeted MHC class I restricted epitopes represents one mechanism for immune escape in HCV, many targeted epitopes remain intact under circumstances of viral persistence. In order to explore alternative mechanisms of HCV immune evasion, we analyzed patterns of expression of a major inhibitory receptor on T cells, programmed death-1 (PD-1), from the time of initial infection and correlated these with HCV RNA levels, outcome of infection, and sequence escape within the targeted epitope. We show that the level of PD-1 expression in early HCV infection is significantly higher on HCV-specific T cells from those who progress to chronic HCV infection compared to those who clear infection. This correlation is independent of HCV RNA levels, compatible with the notion that high PD-1 expression on HCV-specific CD8 T cells during acute infection inhibits viral clearance. Viral escape during persistent infection is associated with reduction in PD-1 levels on the surface of HCV specific T cells, supporting the necessity of ongoing antigenic stimulation of T cells for maintenance of PD-1 expression. These results support the idea that PD-1 expression on T cells specific for nonescaped epitopes contributes to viral persistence and suggest that PD-1 blockade may alter the outcome of HCV infection. PMID:19050238

  17. Tumor Antigen Specific Activation of Primary Human T-Cells Expressing a Virally Encoded Chimeric T-Cell Receptor Specific for p185HER2

    Institute of Scientific and Technical Information of China (English)

    杨建民; MichaelSFRIEDMAN; ChristopherMREYNOLDS; MarianneTHUBEN; LeeWILKE; JenniferFULLER; 李桥; ZeligESHHAR; JamesJMULE; KevimTMCDONAGH

    2004-01-01

    We have developed and tested chimeric T-cell receptors (TCR) specific for p185HER2. In these experiments,retroviral vectors expressing the N297 or N29ξ receptors were constructed in pRET6. Amphotropic viral producer cells were established in the GALV-based PG13 packaging cell line. Ficoll purified human peripheral blood lymphocytes (PBL) were vitally transduced using an optimized protocol incorporating activation with immobilized anti-CD3/anti-CD28 monoclonal antibodies, followed by viral infection in the presence of fibronectin fragment CH296. Transduced cells were co-cultured with human tumor cell lines that overexpress (SK-OV-3) or underexpress (MCF7) p185HER2 to assay for antigen specific immune responses. Both CD4+ and CD8+ T-cells transduced with the N297 or N29ξ chTCR demonstrated HER2-specific antigen responses, as determined by release of Th1 like cytokines, and cellular cytotoxicity assays. Our results support the feasibility of adoptive immunothempy with genetically modified T-cells expressing a chTCR specific for p185HER2.

  18. Local CD4 and CD8 T-cell reactivity to HSV-1 antigens documents broad viral protein expression and immune competence in latently infected human trigeminal ganglia.

    Directory of Open Access Journals (Sweden)

    Monique van Velzen

    2013-08-01

    Full Text Available Herpes simplex virus type 1 (HSV-1 infection results in lifelong chronic infection of trigeminal ganglion (TG neurons, also referred to as neuronal HSV-1 latency, with periodic reactivation leading to recrudescent herpetic disease in some persons. HSV-1 proteins are expressed in a temporally coordinated fashion during lytic infection, but their expression pattern during latent infection is largely unknown. Selective retention of HSV-1 reactive T-cells in human TG suggests their role in controlling reactivation by recognizing locally expressed HSV-1 proteins. We characterized the HSV-1 proteins recognized by virus-specific CD4 and CD8 T-cells recovered from human HSV-1-infected TG. T-cell clusters, consisting of both CD4 and CD8 T-cells, surrounded neurons and expressed mRNAs and proteins consistent with in situ antigen recognition and antiviral function. HSV-1 proteome-wide scans revealed that intra-TG T-cell responses included both CD4 and CD8 T-cells directed to one to three HSV-1 proteins per person. HSV-1 protein ICP6 was targeted by CD8 T-cells in 4 of 8 HLA-discordant donors. In situ tetramer staining demonstrated HSV-1-specific CD8 T-cells juxtaposed to TG neurons. Intra-TG retention of virus-specific CD4 T-cells, validated to the HSV-1 peptide level, implies trafficking of viral proteins from neurons to HLA class II-expressing non-neuronal cells for antigen presentation. The diversity of viral proteins targeted by TG T-cells across all kinetic and functional classes of viral proteins suggests broad HSV-1 protein expression, and viral antigen processing and presentation, in latently infected human TG. Collectively, the human TG represents an immunocompetent environment for both CD4 and CD8 T-cell recognition of HSV-1 proteins expressed during latent infection. HSV-1 proteins recognized by TG-resident T-cells, particularly ICP6 and VP16, are potential HSV-1 vaccine candidates.

  19. Performance evaluation of new automated hepatitis B viral markers in the clinical laboratory: two quantitative hepatitis B surface antigen assays and an HBV core-related antigen assay.

    Science.gov (United States)

    Park, Yongjung; Hong, Duck Jin; Shin, Saeam; Cho, Yonggeun; Kim, Hyon-Suk

    2012-05-01

    We evaluated quantitative hepatitis B surface antigen (qHBsAg) assays and a hepatitis B virus (HBV) core-related antigen (HBcrAg) assay. A total of 529 serum samples from patients with hepatitis B were tested. HBsAg levels were determined by using the Elecsys (Roche Diagnostics, Indianapolis, IN) and Architect (Abbott Laboratories, Abbott Park, IL) qHBsAg assays. HBcrAg was measured by using Lumipulse HBcrAg assay (Fujirebio, Tokyo, Japan). Serum aminotransferases and HBV DNA were respectively quantified by using the Hitachi 7600 analyzer (Hitachi High-Technologies, Tokyo, Japan) and the Cobas AmpliPrep/Cobas TaqMan test (Roche). Precision of the qHBsAg and HBcrAg assays was assessed, and linearity of the qHBsAg assays was verified. All assays showed good precision performance with coefficients of variation between 4.5% and 5.3% except for some levels. Both qHBsAg assays showed linearity from 0.1 to 12,000.0 IU/mL and correlated well (r = 0.9934). HBsAg levels correlated with HBV DNA (r = 0.3373) and with HBcrAg (r = 0.5164), and HBcrAg also correlated with HBV DNA (r = 0.5198; P HBcrAg assays.

  20. Targeting of non-dominant antigens as a vaccine strategy to broaden T-cell responses during chronic viral infection

    DEFF Research Database (Denmark)

    Holst, Peter Johannes; Jensen, Benjamin Anderschou Holbech; Ragonnaud, Emeline;

    2015-01-01

    challenge with live virus, the CD8+ T cells specific for vaccine-encoded epitopes, displayed a phenotype typically associated with prolonged/persistent antigenic stimulation marked by high levels of KLRG-1, as compared to T cells reacting to epitopes not included in the vaccine. Notably, this association...

  1. Ability of Lactococcus lactis to export viral capsid antigens: a crucial step for development of live vaccines

    NARCIS (Netherlands)

    Dieye, Y.; Hoekman, A.J.W.; Clier, F.; Juillard, V.; Boot, H.J.; Piard, J.C.

    2003-01-01

    Thefood grade bacterium Lactococcus lactis is a potential vehicle for protein delivery in the gastrointestinal tract. As a model, we constructed lactococcal strains producing antigens of infectious bursal disease virus (IBDV). IBDV infects chickens and causes depletion of B-lymphoid cells in the bur

  2. Human polyoma JC virus minor capsid proteins, VP2 and VP3, enhance large T antigen binding to the origin of viral DNA replication: evidence for their involvement in regulation of the viral DNA replication.

    Science.gov (United States)

    Saribas, A Sami; Mun, Sarah; Johnson, Jaslyn; El-Hajmoussa, Mohammad; White, Martyn K; Safak, Mahmut

    2014-01-20

    JC virus (JCV) lytically infects the oligodendrocytes in the central nervous system in a subset of immunocompromized patients and causes the demyelinating disease, progressive multifocal leukoencephalopathy. JCV replicates and assembles into infectious virions in the nucleus. However, understanding the molecular mechanisms of its virion biogenesis remains elusive. In this report, we have attempted to shed more light on this process by investigating molecular interactions between large T antigen (LT-Ag), Hsp70 and minor capsid proteins, VP2/VP3. We demonstrated that Hsp70 interacts with VP2/VP3 and LT-Ag; and accumulates heavily in the nucleus of the infected cells. We also showed that VP2/VP3 associates with LT-Ag through their DNA binding domains resulting in enhancement in LT-Ag DNA binding to Ori and induction in viral DNA replication. Altogether, our results suggest that VP2/VP3 and Hsp70 actively participate in JCV DNA replication and may play critical roles in coupling of viral DNA replication to virion encapsidation.

  3. Detection of liver HBc antigen and its antibody in sera from viral hepatitis by the immunofluorescent complement technique

    Directory of Open Access Journals (Sweden)

    Tsuji,Takao

    1976-02-01

    Full Text Available Hepatitis B core antigen (HBc Ag and hepatitis B surface antigen (HBs Ag were detected in the liver tissue of a patient with chronic aggressive hepatitis by the immunofluorescent complement technique. The presence of anti-HBc was examined by the same method in 67 human sera previously tested for HBs Ag, anti-HBs and s-GPT levels. HBc Ag was localized mainly in the nucleus and sometimes in the cytoplasm of the hepatic cells. HBs Ag was found only in the cytoplasm. The focal area of HBc Ag positive hepatic cells seemed to correspond to the HBs Ag positive cells. Double staining demonstrated the simultaneous presence of HBs Ag and HBc Ag in individual cells. Anti-HBc positive serum was found in 46 (68.7% cases. Forty-eight (71.6% indicated a combination of HBs Ag and anti-HBc.

  4. CD8 T cells in innate immune responses: using STAT4-dependent but antigen-independent pathways to gamma interferon during viral infection.

    Science.gov (United States)

    Suarez-Ramirez, Jenny E; Tarrio, Margarite L; Kim, Kwangsin; Demers, Delia A; Biron, Christine A

    2014-10-21

    The cytokine gamma interferon (IFN-γ), with antimicrobial and immunoregulatory functions, can be produced by T cells following stimulation through their T cell receptors (TCRs) for antigen. The innate cytokines type 1 IFNs and interleukin-12 (IL-12) can also stimulate IFN-γ production by natural killer (NK) but not naive T cells. High basal expression of signal transducer and activator of transcription 4 (STAT4), used by type 1 IFN and IL-12 to induce IFN-γ as well as CD25, contributes to the NK cell responses. During acute viral infections, antigen-specific CD8 T cells are stimulated to express elevated STAT4 and respond to the innate factors with IFN-γ production. Little is known about the requirements for cytokine compared to TCR stimulation. Primary infections of mice with lymphocytic choriomeningitis virus (LCMV) demonstrated that although the elicited antigen-specific CD8 T cells acquired STAT4-dependent innate cytokine responsiveness for IFN-γ and CD25 induction ex vivo, TCR stimulation induced these through STAT4-independent pathways. During secondary infections, LCMV-immune CD8 T cells had STAT4-dependent IFN-γ expression at times of innate cytokine induction but subsequently expanded through STAT4-independent pathways. At times of innate cytokine responses during infection with the antigen-distinct murine cytomegalovirus virus (MCMV), NK and LCMV-immune CD8 T cells both had activation of pSTAT4 and IFN-γ. The T cell IFN-γ response was STAT4 and IL-12 dependent, but antigen-dependent expansion was absent. By dissecting requirements for STAT4 and antigen, this work provides novel insights into the endogenous regulation of cytokine and proliferative responses and demonstrates conditioning of innate immunity by experience. Importance: Understanding the regulation and function of adaptive immunity is key to the development of new and improved vaccines. Its CD8 T cells are activated through antigen-specific receptors to contribute to long

  5. Promiscuous CTL recognition of viral epitopes on multiple human leukocyte antigens: biological validation of the proposed HLA A24 supertype.

    Science.gov (United States)

    Burrows, Scott R; Elkington, Rebecca A; Miles, John J; Green, Katherine J; Walker, Susan; Haryana, Sofia M; Moss, Denis J; Dunckley, Heather; Burrows, Jacqueline M; Khanna, Rajiv

    2003-08-01

    Multiple HLA class I alleles can bind peptides with common sequence motifs due to structural similarities in the peptide binding cleft, and these groups of alleles have been classified into supertypes. Nine major HLA supertypes have been proposed, including an A24 supertype that includes A*2301, A*2402, and A*3001. Evidence for this A24 supertype is limited to HLA sequence homology and/or similarity in peptide binding motifs for the alleles. To investigate the immunological relevance of this proposed supertype, we have examined two viral epitopes (from EBV and CMV) initially defined as HLA-A*2301-binding peptides. The data clearly demonstrate that each peptide could be recognized by CTL clones in the context of A*2301 or A*2402; thus validating the inclusion of these three alleles within an A24 supertype. Furthermore, CTL responses to the EBV epitope were detectable in both A*2301(+) and A*2402(+) individuals who had been previously exposed to this virus. These data substantiate the biological relevance of the A24 supertype, and the identification of viral epitopes with the capacity to bind promiscuously across this supertype could aid efforts to develop CTL-based vaccines or immunotherapy. The degeneracy in HLA restriction displayed by some T cells in this study also suggests that the dogma of self-MHC restriction needs some refinement to accommodate foreign peptide recognition in the context of multiple supertype alleles.

  6. Targeting of non-dominant antigens as a vaccine strategy to broaden T-cell responses during chronic viral infection

    DEFF Research Database (Denmark)

    Holst, Peter Johannes; Jensen, Benjamin Anderschou Holbech; Ragonnaud, Emeline

    2015-01-01

    In this study, we compared adenoviral vaccine vectors with the capacity to induce equally potent immune responses against non-dominant and immunodominant epitopes of murine lymphocytic choriomeningitis virus (LCMV). Our results demonstrate that vaccination targeting non-dominant epitopes facilita......In this study, we compared adenoviral vaccine vectors with the capacity to induce equally potent immune responses against non-dominant and immunodominant epitopes of murine lymphocytic choriomeningitis virus (LCMV). Our results demonstrate that vaccination targeting non-dominant epitopes...... by vaccination. In addition, our findings suggest that prior adenoviral vaccination is not likely to negatively impact the long-term and protective immune response induced and maintained by a vaccine-attenuated chronic viral infection....

  7. JC virus small T antigen binds phosphatase PP2A and Rb family proteins and is required for efficient viral DNA replication activity.

    Directory of Open Access Journals (Sweden)

    Brigitte Bollag

    Full Text Available BACKGROUND: The human polyomavirus, JC virus (JCV produces five tumor proteins encoded by transcripts alternatively spliced from one precursor messenger RNA. Significant attention has been given to replication and transforming activities of JCV's large tumor antigen (TAg and three T' proteins, but little is known about small tumor antigen (tAg functions. Amino-terminal sequences of tAg overlap with those of the other tumor proteins, but the carboxy half of tAg is unique. These latter sequences are the least conserved among the early coding regions of primate polyomaviruses. METHODOLOGY AND FINDINGS: We investigated the ability of wild type and mutant forms of JCV tAg to interact with cellular proteins involved in regulating cell proliferation and survival. The JCV P99A tAg is mutated at a conserved proline, which in the SV40 tAg is required for efficient interaction with protein phosphatase 2A (PP2A, and the C157A mutant tAg is altered at one of two newly recognized LxCxE motifs. Relative to wild type and C157A tAgs, P99A tAg interacts inefficiently with PP2A in vivo. Unlike SV40 tAg, JCV tAg binds to the Rb family of tumor suppressor proteins. Viral DNAs expressing mutant t proteins replicated less efficiently than did the intact JCV genome. A JCV construct incapable of expressing tAg was replication-incompetent, a defect not complemented in trans using a tAg-expressing vector. CONCLUSIONS: JCV tAg possesses unique properties among the polyomavirus small t proteins. It contributes significantly to viral DNA replication in vivo; a tAg null mutant failed to display detectable DNA replication activity, and a tAg substitution mutant, reduced in PP2A binding, was replication-defective. Our observation that JCV tAg binds Rb proteins, indicates all five JCV tumor proteins have the potential to influence cell cycle progression in infected and transformed cells. It remains unclear how these proteins coordinate their unique and overlapping functions.

  8. Impact of acute malaria on pre-existing antibodies to viral and vaccine antigens in mice and humans.

    Directory of Open Access Journals (Sweden)

    Simran Banga

    Full Text Available Vaccine-induced immunity depends on long-lived plasma cells (LLPCs that maintain antibody levels. A recent mouse study showed that Plasmodium chaubaudi infection reduced pre-existing influenza-specific antibodies--raising concerns that malaria may compromise pre-existing vaccine responses. We extended these findings to P. yoelii infection, observing decreases in antibodies to model antigens in inbred mice and to influenza in outbred mice, associated with LLPC depletion and increased susceptibility to influenza rechallenge. We investigated the implications of these findings in Malian children by measuring vaccine-specific IgG (tetanus, measles, hepatitis B before and after the malaria-free 6-month dry season, 10 days after the first malaria episode of the malaria season, and after the subsequent dry season. On average, vaccine-specific IgG did not decrease following acute malaria. However, in some children malaria was associated with an accelerated decline in vaccine-specific IgG, underscoring the need to further investigate the impact of malaria on pre-existing vaccine-specific antibodies.

  9. Analyzing titers of antibodies against bacterial and viral antigens, and bacterial toxoids in the intravenous immunoglobulins utilized in Taiwan.

    Science.gov (United States)

    Wu, Chi-Yu; Wang, Hsiu-Chi; Wang, Kun-Teng; Yang-Chih Shih, Daniel; Lo, Chi-Fang; Wang, Der-Yuan

    2013-03-01

    Intravenous immunoglobulin (IVIG) manufactured from human plasma contains IgG as the primary ingredient, and is used for indications such as immunodeficiency syndrome. Available IVIGs in Taiwan are either manufactured from Taiwanese or North American plasma. The effectiveness of the national immunization program of Taiwan can be evaluated by analyzing and comparing IVIG antibody titers that are induced through the corresponding vaccines (tetanus, diphtheria, and pertussis, measles, rubella, hepatitis A, hepatitis B and varicella). Both enzyme-linked immunosorbent assay (ELISA) and the in vitro neutralization test demonstrated that all IVIGs provide adequate clinical protection against diphtheria and tetanus toxins. ELISA results further revealed that plasma of Taiwanese subjects contains higher levels of pertussis toxin and filamentous hemagglutinin antibodies, when compared to foreign IVIGs. This may be related to the later adoption of acellular pertussis vaccine in Taiwan. Antibodies titers against measles, rubella, hepatitis A, and varicella-zoster virus were otherwise low. Low titers of hepatitis B surface antigen antibodies are present in Taiwanese plasma IVIG, indicating immune memory decline or loss. In conclusion, our results show that Taiwanese IVIG contains varying titers of vaccine-induced antibodies, and serves as a guide for future amendments to Taiwan's immunization program.

  10. Viral blips during long-term treatment with standard or double dose lamivudine in HBe antigen negative chronic hepatitis B

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To evaluate safety and effect on hepatitis B virus (HBV) suppression of a long-term treatment with lamivudine (LAM) at standard (100 mg/d) or double (200 mg/d) dose in chronic hepatitis B. METHODS: This was a case study with matched controls (1:3) in patients with chronic hepatitis B with anti-Hbe antibodies. RESULTS: Twelve patients received LAM 200 mg/d and 35 LAM 100 mg/d, for a median of 28 mo. A primary response (PR; I.e. Negative HBV-DNA with Amplicor assay) was achieved in 100% of LAM-200 patients and 83% of LAM-100 patients. A virological breakthrough occurred in 16.7 and 24.7%, respectively, of the PR-patients, with the appearance of typical LAM resistance mutations in all but one patient. Viremia blips (I.e. Transient HBV-DNA below 80 IU/Ml in patients who tested negative at Amplicor assay) were detected using a real time polymerase chain reaction (PCR) and occurred in seven out of nine patients with subsequent BT and in four out of 32 patients with end-of-study response (77.7% vs 12.5%; P = 0.001) at chi-square test). At the end of the study, 51.4% of LAM-100 patients and 83.3% of LAM-200 patients had remained stably HBV-DNA negative. Double-dose LAM was well tolerated. CONCLUSION: Long-term treatment of anti-Hbe positive chronic hepatitis B with double dose lamivudine causes a more profound and stable viral suppression as compared to conventional treatment.

  11. Development of an enhanced bovine viral diarrhea virus subunit vaccine based on E2 glycoprotein fused to a single chain antibody which targets to antigen-presenting cells.

    Science.gov (United States)

    Pecora, Andrea; Malacari, Darío A; Pérez Aguirreburualde, María S; Bellido, Demian; Escribano, José M; Dus Santos, María J; Wigdorovitz, Andrés

    2015-01-01

    Bovine viral diarrhea virus (BVDV) is an important cause of economic losses worldwide. E2 is an immunodominant protein and a promising candidate to develop subunit vaccines. To improve its immunogenicity, a truncated E2 (tE2) was fused to a single chain antibody named APCH, which targets to antigen-presenting cells. APCH-tE2 and tE2 proteins were expressed in the baculovirus system and their immunogenicity was firstly compared in guinea pigs. APCH-tE2 vaccine was the best one to evoke a humoral response, and for this reason, it was selected for a cattle vaccination experiment. All the bovines immunized with 1.5 μg of APCH-tE2 developed high levels of neutralizing antibodies against BVDV up to a year post-immunization, demonstrating its significant potential as a subunit vaccine. This novel vaccine is undergoing scale-up and was transferred to the private sector. Nowadays, it is being evaluated for registration as the first Argentinean subunit vaccine for cattle.

  12. Cloning of the rhesus lymphocryptovirus viral capsid antigen and Epstein-Barr virus-encoded small RNA homologues and use in diagnosis of acute and persistent infections.

    Science.gov (United States)

    Rao, P; Jiang, H; Wang, F

    2000-09-01

    Epstein-Barr virus (EBV) is the most common cause of infectious mononucleosis and is associated with the development of several human malignancies. A closely related herpesvirus in the same lymphocryptovirus (LCV) genera as EBV naturally infects rhesus monkeys and provides an important animal model for studying EBV pathogenesis. We cloned the small viral capsid antigen (sVCA) homologue from the rhesus LCV and developed a peptide enzyme-linked immunosorbent assay (ELISA) to determine whether epitopes in the rhesus LCV sVCA are a reliable indicator of rhesus LCV infection. In order to define a "gold standard" for rhesus LCV infection, we also cloned the EBV-encoded small RNA 1 (EBER1) and EBER2 homologues from rhesus LCV and developed a reverse transcription (RT)-PCR assay to detect persistent LCV infection in rhesus monkey peripheral blood lymphocytes. Animals from a conventional and a hand-reared colony were studied to compare the prevalence of rhesus LCV infection in the two groups. There was a 100% correlation between the peptide ELISA and EBER RT-PCR results for rhesus LCV infection. In addition, specificity for LCV infection and exclusion of potential cross-reactivity to the rhesus rhadinovirus sVCA homologue could be demonstrated using sera from experimentally infected animals. These studies establish two novel assays for reliable diagnosis of acute and persistent rhesus LCV infections. The rhesus LCV sVCA peptide ELISA provides a sensitive and reliable assay for routine screening, and these studies of the hand-reared colony confirm the feasibility of raising rhesus LCV-naive animals.

  13. Epstein-Barr virus glycoprotein gH/gL antibodies complement IgA-viral capsid antigen for diagnosis of nasopharyngeal carcinoma.

    Science.gov (United States)

    Li, Rui-Chen; Du, Yong; Zeng, Qiu-Yao; Tang, Lin-Quan; Zhang, Hua; Li, Yan; Liu, Wan-Li; Zhong, Qian; Zeng, Mu-Sheng; Huang, Xiao-Ming

    2016-03-29

    To determine whether measuring antibodies against Epstein-Barr virus (EBV) glycoprotein gH/gL in serum could improve diagnostic accuracy in nasopharyngeal carcinoma (NPC) cases, gH/gL expressed in a recombinant baculovirus system was used in an enzyme-linked immunosorbent assay (ELISA) to detect antibodies in two independent cohorts. Binary logistic regression analyses were performed using results from a training cohort (n = 406) to establish diagnostic mathematical models, which were validated in a second independent cohort (n = 279). Levels of serum gH/gL antibodies were higher in NPC patients than in healthy controls (p gH/gL ELISA had a sensitivity of 83.7%, specificity of 82.3% and area under the curve (AUC) of 0.893 (95% CI, 0.862-0.924) for NPC diagnosis. Furthermore, gH/gL maintained diagnostic capacity in IgA-VCA negative NPC patients (sensitivity = 78.1%, specificity = 82.3%, AUC = 0.879 [95% CI, 0.820 - 0.937]). Combining gH/gL and viral capsid antigen (VCA) detection improved diagnostic capacity as compared to individual tests alone in both the training cohort (sensitivity = 88.5%, specificity = 97%, AUC = 0.98 [95% CI, 0.97 - 0.991]), and validation cohort (sensitivity = 91.2%, specificity = 96.5%, AUC = 0.97 [95% CI, 0.951-0.988]). These findings suggest that EBV gH/gL detection complements VCA detection in the diagnosis of NPC and aids in the identification of patients with VCA-negative NPC.

  14. Collection of corneal impression cytology directly on a sterile glass slide for the detection of viral antigen: An inexpensive and simple technique for the diagnosis of HSV epithelial keratitis – A pilot study

    Directory of Open Access Journals (Sweden)

    Bandlapally Sesha

    2001-09-01

    Full Text Available Abstract Background Herpes simplex keratitis (HSK is a sight threatening ocular infection and occurs worldwide. A prompt laboratory diagnosis is often very useful. Conventional virology techniques are often expensive and time consuming. We describe here a highly economical, simple, rapid and sensitive technique for the collection of impression cytology, for the laboratory diagnosis of HSK. Methods Fifteen patients with a clinical diagnosis of HSK (either dendritic or geographic ulcers and five patients with other corneal infections (Mycotic keratitis, n = 3, Bacterial keratitis, n = 2 were included in the study. Corneal impression cytology specimens were collected using a sterile glass slide with polished edges instead of a membrane, by pressing the surface of one end of the slide firmly, but gently on the corneal lesion. Additionally, corneal scrapings were collected following the impression cytology procedure. Impression cytology and corneal scrapings were stained by an immunoperoxidase or immunofluorescence assay for the detection of HSV-1 antigen using a polyclonal antibody to HSV-1. Corneal scrapings were processed for viral cultures by employing a shell vial assay. Results This simple technique allowed the collection of adequate corneal epithelial cells for the detection of HSV-1 antigen in a majority of the patients. HSV-1 antigen was detected in 12/15 (80% cases while virus was isolated from 5/15 (33.3% patients with HSK. All the patients with a clinical diagnosis of HSK (n = 15 were confirmed by virological investigations (viral antigen detection and/or viral cultures. HSV-1 antigen was detected in the impression cytology smears and corneal scrapings in 11/15 (73.3% and 12/15 (80% of the patients, respectively (P = 1.00. None of the patients in the control group were positive for viral antigen or virus isolation. Minimal background staining was seen in impression cytology smears, while there was some background staining in corneal

  15. Análise antigênica e molecular de amostras citopáticas do vírus da diarréia viral bovina Antigenic and molecular analysis of cytopathic isolates of bovine viral diarrhea virus

    Directory of Open Access Journals (Sweden)

    Fernando Luiz Tobias

    2000-03-01

    Mucosas.Seven cytopathic isolates of bovine viral diarrhea virus (BVDV isolated from clinical cases and blood of calves from herds with reproductive problems were analysed. All isolates contained a mixture of cytopathic (cp and noncytopathic (ncp viruses which were biologically cloned yielding pure populations of viruses of either biotype. The cp and ncp viruses obtained by cloning were characterized antigenically with a panel of monoclonal antibodies (MAbs and regarding to the expression of the non-structural polypeptide NS3. The analysis of MAb binding revealed two patterns of reactivity: 1. In five isolates, the cp and ncp viruses from the same isolate were antigenically very similar to each other, suggesting they represent true "pairs"of viruses. 2. Two isolates, however, yielded cp and ncp viruses antigenically different from each other. Western immunoblot analysis of non-structural polypeptides of ncp viruses revealed a unique band of reactivity, with a mass of approximately 125kDa, corresponding to the NS23 of the standard BVDV Singer strain. In addition to NS23, the cp viruses expressed a polypeptide of approximatelly 80kDa, corresponding to the NS3. The NS23 of two cp viruses displayed an altered migration in SDS-PAGE compared to the other viruses. In one virus, the NS23 had a molecular mass lower than expected whereas in other virus, two bands of reactivity were observed: one smaller and another bigger than the standard NS23, respectively. Our findings confirm previous results that cytopathic BVDV field isolates usually contain a mixture of viruses of both biotypes and that cytopathogenicity correlates with the expression of NS3. The isolation of cp viruses from the blood of clinically normal cattle, however, demonstrates that their occurrence is not restricted to cases of mucosal disease.

  16. High-programmed death-1 levels on hepatitis C virus-specific T cells during acute infection are associated with viral persistence and require preservation of cognate antigen during chronic infection.

    Science.gov (United States)

    Rutebemberwa, Alleluiah; Ray, Stuart C; Astemborski, Jacquie; Levine, Jordana; Liu, Lin; Dowd, Kimberly A; Clute, Shalyn; Wang, Changyu; Korman, Alan; Sette, Alessandro; Sidney, John; Pardoll, Drew M; Cox, Andrea L

    2008-12-15

    Hepatitis C virus (HCV) is an important human pathogen that represents a model for chronic infection given that the majority of infected individuals fail to clear the infection despite generation of virus-specific T cell responses during the period of acute infection. Although viral sequence evolution at targeted MHC class I-restricted epitopes represents one mechanism for immune escape in HCV, many targeted epitopes remain intact under circumstances of viral persistence. To explore alternative mechanisms of HCV immune evasion, we analyzed patterns of expression of a major inhibitory receptor on T cells, programmed death-1 (PD-1), from the time of initial infection and correlated these with HCV RNA levels, outcome of infection, and sequence escape within the targeted epitope. We show that the level of PD-1 expression in early HCV infection is significantly higher on HCV-specific T cells from subjects who progress to chronic HCV infection than from those who clear infection. This correlation is independent of HCV RNA levels, compatible with the notion that high PD-1 expression on HCV-specific CD8 T cells during acute infection inhibits viral clearance. Viral escape during persistent infection is associated with reduction in PD-1 levels on the surface of HCV-specific T cells, supporting the necessity of ongoing antigenic stimulation of T cells for maintenance of PD-1 expression. These results support the idea that PD-1 expression on T cells specific for nonescaped epitopes contributes to viral persistence and suggest that PD-1 blockade may alter the outcome of HCV infection.

  17. The detection of infectious bronchitis viral antigen by means of immunohistochemical technique in broiler chicken infected with I-269 IB isolate or injected with H-120 live vaccine

    Directory of Open Access Journals (Sweden)

    Rini Damayanti

    2001-12-01

    Full Text Available A study was carried out to detect the antigen of infectious bronchitis vius (IBV in broiler chicken by means of immunohistochemical technique. A total of 150 - fourteen days old broiler chicken were divided into three groups i.e. 50 chicken were infected with an IB isolate of I-269, 50 chicken were injected with H-120 life vaccine, and 50 chicken served as un-treated control. Clinical signs and gross pathological changes were observed. Each of five chicken of each group were necropsied at 1, 2, 3, 4, 7, 10, 14, 21, 28, and 35 day(s post infection/vaccination. The antigen could be detected at one day through 35 days post vaccination/infection. In the vaccinated group, histopathological lesions and the detected antigen were minimal. In contrast, the infected chicken showed varied histolopathological lesion in accordance with the numerous antigens. The antigen were observed in the lymphocytes/macrophages in the trachea, lungs and kidney, and in the epithelium of trachea, alveoli, broncheolus and tubular sitoplasm of the kidney of both vaccinated and infected groups. In the infected group, antigen was also detected in the lymphocytes and macrophages of the affected organs.

  18. Understanding MHC class I presentation of viral antigens by human dendritic cells as a basis for rational design of therapeutic vaccines

    NARCIS (Netherlands)

    N. van Montfoort (Nadine); E. van der Aa (Evelyn); A.M. Woltman (Andrea)

    2014-01-01

    textabstractEffective viral clearance requires the induction of virus-specific CD8+ cytotoxic T lymphocytes (CTL). Since dendritic cells (DC) have a central role in initiating and shaping virus-specific CTL responses, it is important to understand how DC initiate virus-specific CTL responses. Some v

  19. INDUCTION OF A SECRETORY IGA RESPONSE IN THE MURINE FEMALE UROGENITAL TRACT BY IMMUNIZATION OF THE LUNGS WITH LIPOSOME-SUPPLEMENTED VIRAL SUBUNIT ANTIGEN

    NARCIS (Netherlands)

    DEHAAN, A; RENEGAR, KB; SMALL, PA; WILSCHUT, J

    1995-01-01

    This study demonstrates that liposomes administered to the lower respiratory tract of mice have the capacity to stimulate secretory IgA (s-IgA) antibody production in the female urogenital system. Total respiratory tract immunization of mice with influenza virus subunit antigen simply mixed with neg

  20. Viral Hepatitis

    Science.gov (United States)

    ... Public Home » For Veterans and the Public Viral Hepatitis Menu Menu Viral Hepatitis Viral Hepatitis Home For ... the Public Veterans and Public Home How is Hepatitis C Treated? Find the facts about the newest ...

  1. Preliminary X-ray diffraction analysis of crystals from the recombinantly expressed human major histocompatibility antigen HLA-B*2704 in complex with a viral peptide and with a self-peptide

    Energy Technology Data Exchange (ETDEWEB)

    Loll, Bernhard [Institut für Chemie/Kristallographie, Freie Universität Berlin, Takustrasse 6, 14195 Berlin (Germany); Zawacka, Anna [Institut für Immungenetik, Charité-Universitätsmedizin Berlin, Campus Virchow-Klinikum, Humboldt-Universität zu Berlin, Spandauer Damm 130, 14050 Berlin (Germany); Biesiadka, Jacek [Institut für Chemie/Kristallographie, Freie Universität Berlin, Takustrasse 6, 14195 Berlin (Germany); Petter, Cordula; Rückert, Christine [Institut für Immungenetik, Charité-Universitätsmedizin Berlin, Campus Virchow-Klinikum, Humboldt-Universität zu Berlin, Spandauer Damm 130, 14050 Berlin (Germany); Saenger, Wolfram [Institut für Chemie/Kristallographie, Freie Universität Berlin, Takustrasse 6, 14195 Berlin (Germany); Uchanska-Ziegler, Barbara; Ziegler, Andreas, E-mail: andreas.ziegler@charite.de [Institut für Immungenetik, Charité-Universitätsmedizin Berlin, Campus Virchow-Klinikum, Humboldt-Universität zu Berlin, Spandauer Damm 130, 14050 Berlin (Germany); Institut für Chemie/Kristallographie, Freie Universität Berlin, Takustrasse 6, 14195 Berlin (Germany)

    2005-10-01

    Crystallization of HLA-B*2704 in complex with two peptides. The product of the human leukocyte antigen (HLA) gene HLA-B*2704 differs from that of the prototypical subtype HLA-B*2705 by three amino acids at heavy-chain residues 77 (Ser instead of Asp), 152 (Glu instead of Val) and 211 (Gly instead of Ala). In contrast to the ubiquitous HLA-B*2705 subtype, HLA-B*2704 occurs only in orientals. Both subtypes are strongly associated with spondyloarthropathies and the peptides presented by these subtypes are suspected to play a role in disease pathogenesis. HLA-B*2704 was crystallized in complex with a viral peptide and with a self-peptide using the hanging-drop vapour-diffusion method with PEG as a precipitant. Both crystals belong to space group P2{sub 1}2{sub 1}2{sub 1}. Data sets were collected to 1.60 Å (complex with the self-peptide pVIPR) or to 1.90 Å (complex with the viral peptide pLMP2) resolution using synchrotron radiation. With HLA-B*2705 complexed with pVIPR as a search model, unambiguous molecular-replacement solutions were found for the complexes of HLA-B*2704 with both peptides.

  2. Influence of plasminogen activator inhibitor-1 (SERPINE1) 4G/5G polymorphism on circulating SERPINE-1 antigen expression in HCC associated with viral infection.

    Science.gov (United States)

    Divella, Rosa; Mazzocca, Antonio; Gadaleta, Cosimo; Simone, Giovanni; Paradiso, Angelo; Quaranta, Michele; Daniele, Antonella

    2012-01-01

    Hepatocarcinogenesis is heavily influenced by chronic hepatitis B (HBV) and C (HCV) infection. Elevated levels of plasminogen activator inhibitor-1 (SERPINE1/PAI-1) have been reported in patients with hepatocellular carcinoma (HCC) associated with viral infection. The gene encoding SERPINE1 is highly polymorphic and the frequently associated 4/5 guanosine (4G/5G) polymorphism in the gene promoter may influence its expression. Here, we investigated the distribution of genotypes and the frequency of alleles of the 4G/5G polymorphism in patients with HCC, the influence of the 4G/5G polymorphism on plasma SERPINE1 levels and its association with viral infection. A total of 75 patients with HCC were enrolled: 32 (42.6%) were HBV(+)/HCV(+), 11 (14.6%) were only HCV(+), and 32 (42.6%) were negative for both viruses. A control group of healthy donors was also enrolled (n=50). SERPINE1 plasma concentrations were determined by ELISA and the detection of the promoter 4G/5G polymorphism was performed by an allele-specific PCR analysis. We found that the frequency of both the 4G/4G genotype (p=0.02) and the 4G allele (p=0.006) were significantly higher in patients with HCC compared to the control group, and particularly higher in patients with HCC co-infected with HBV(+)/HCV(+) than in those with no viral infection. We also found that patients with the 4G/4G genotype had significantly higher plasma SERPINE1 protein levels when compared with patients with the 4G/5G or 5G/5G genotype (p5G SERPINE1 polymorphism with a higher level of SERPINE1 protein in patients with HCC with HBV(+)/HCV(+) than those without infection, suggest the presence of two distinct pathogenic mechanisms in hepatocarcinogenesis, depending on the etiology.

  3. Improving Mycobacterium bovis bacillus Calmette-Guerin as a vaccine delivery vector for viral antigens by incorporation of glycolipid activators of NKT cells.

    Directory of Open Access Journals (Sweden)

    Manjunatha M Venkataswamy

    Full Text Available Recombinant Mycobacterium bovis bacillus Calmette-Guèrin (rBCG has been explored as a vector for vaccines against HIV because of its ability to induce long lasting humoral and cell mediated immune responses. To maximize the potential for rBCG vaccines to induce effective immunity against HIV, various strategies are being employed to improve its ability to prime CD8+ T cells, which play an important role in the control of HIV infections. In this study we adopted a previously described approach of incorporating glycolipids that activate CD1d-restricted natural killer T (NKT cells to enhance priming of CD8+ T cells by rBCG strains expressing an SIV Gag antigen (rBCG-SIV gag. We found that the incorporation of the synthetic NKT activating glycolipid α-galactosylceramide (α-GC into rBCG-SIV gag significantly enhanced CD8+ T cell responses against an immunodominant Gag epitope, compared to responses primed by unmodified rBCG-SIV gag. The abilities of structural analogues of α-GC to enhance CD8+ T cell responses to rBCG were compared in both wild type and partially humanized mice that express human CD1d molecules in place of mouse CD1d. These studies identified an α-GC analogue known as 7DW8-5, which has previously been used successfully as an adjuvant in non-human primates, as a promising compound for enhancing immunogenicity of antigens delivered by rBCG.vectors. Our findings support the incorporation of synthetic glycolipid activators of NKT cells as a novel approach to enhance the immunogenicity of rBCG-vectored antigens for induction of CD8+ T cell responses. The glycolipid adjuvant 7DW8-5 may be a promising candidate for advancing to non-human primate and human clinical studies for the development of HIV vaccines based on rBCG vectors.

  4. Improving Mycobacterium bovis Bacillus Calmette-Guèrin as a Vaccine Delivery Vector for Viral Antigens by Incorporation of Glycolipid Activators of NKT Cells

    Science.gov (United States)

    Kharkwal, Shalu S.; Carreño, Leandro J.; Johnson, Alison J.; Kunnath-Velayudhan, Shajo; Liu, Zheng; Bittman, Robert; Jervis, Peter J.; Cox, Liam R.; Besra, Gurdyal S.; Wen, Xiangshu; Yuan, Weiming; Tsuji, Moriya; Li, Xiangming; Ho, David D.; Chan, John; Lee, Sunhee; Frothingham, Richard; Haynes, Barton F.; Panas, Michael W.; Gillard, Geoffrey O.; Sixsmith, Jaimie D.; Korioth-Schmitz, Birgit; Schmitz, Joern E.; Larsen, Michelle H.; Jacobs, William R.; Porcelli, Steven A.

    2014-01-01

    Recombinant Mycobacterium bovis bacillus Calmette-Guèrin (rBCG) has been explored as a vector for vaccines against HIV because of its ability to induce long lasting humoral and cell mediated immune responses. To maximize the potential for rBCG vaccines to induce effective immunity against HIV, various strategies are being employed to improve its ability to prime CD8+ T cells, which play an important role in the control of HIV infections. In this study we adopted a previously described approach of incorporating glycolipids that activate CD1d-restricted natural killer T (NKT) cells to enhance priming of CD8+ T cells by rBCG strains expressing an SIV Gag antigen (rBCG-SIV gag). We found that the incorporation of the synthetic NKT activating glycolipid α-galactosylceramide (α-GC) into rBCG-SIV gag significantly enhanced CD8+ T cell responses against an immunodominant Gag epitope, compared to responses primed by unmodified rBCG-SIV gag. The abilities of structural analogues of α-GC to enhance CD8+ T cell responses to rBCG were compared in both wild type and partially humanized mice that express human CD1d molecules in place of mouse CD1d. These studies identified an α-GC analogue known as 7DW8-5, which has previously been used successfully as an adjuvant in non-human primates, as a promising compound for enhancing immunogenicity of antigens delivered by rBCG.vectors. Our findings support the incorporation of synthetic glycolipid activators of NKT cells as a novel approach to enhance the immunogenicity of rBCG-vectored antigens for induction of CD8+ T cell responses. The glycolipid adjuvant 7DW8-5 may be a promising candidate for advancing to non-human primate and human clinical studies for the development of HIV vaccines based on rBCG vectors. PMID:25255287

  5. Long-term outcome of hepatitis B e antigen-positive patients with compensated cirrhosis treated with interferon alfa. European Concerted Action on Viral Hepatitis (EUROHEP)

    DEFF Research Database (Denmark)

    Fattovich, G; Giustina, G; Realdi, G;

    1997-01-01

    The aim of this study was to evaluate whether interferon alfa (IFN-alpha) treatment-associated virological and biochemical remission improves survival in a cohort of 90 white patients with compensated cirrhosis caused by hepatitis B (Child A) followed for a mean period of 7 years. Inclusion...... criteria were biopsy-proven cirrhosis, hepatitis B e antigen (HBeAg) positivity, abnormal serum aminotransferase levels, exclusion of hepatitis delta virus, and absence of complications of cirrhosis. Of the 40 IFN-treated patients, 27 (67%) showed sustained HBeAg loss with alanine aminotransferase (ALT...

  6. Sharing the burden: antigen transport and firebreaks in immune responses

    OpenAIRE

    Handel, Andreas; Yates, Andrew; Pilyugin, Sergei S.; Antia, Rustom

    2008-01-01

    Communication between cells is crucial for immune responses. An important means of communication during viral infections is the presentation of viral antigen on the surface of an infected cell. Recently, it has been shown that antigen can be shared between infected and uninfected cells through gap junctions, connexin-based channels, that allow the transport of small molecules. The uninfected cell receiving antigen can present it on its surface. Cells presenting viral antigen are detected and ...

  7. Combining viral vectored and protein-in-adjuvant vaccines against the blood-stage malaria antigen AMA1: report on a phase 1a clinical trial.

    Science.gov (United States)

    Hodgson, Susanne H; Choudhary, Prateek; Elias, Sean C; Milne, Kathryn H; Rampling, Thomas W; Biswas, Sumi; Poulton, Ian D; Miura, Kazutoyo; Douglas, Alexander D; Alanine, Daniel Gw; Illingworth, Joseph J; de Cassan, Simone C; Zhu, Daming; Nicosia, Alfredo; Long, Carole A; Moyle, Sarah; Berrie, Eleanor; Lawrie, Alison M; Wu, Yimin; Ellis, Ruth D; Hill, Adrian V S; Draper, Simon J

    2014-12-01

    The development of effective vaccines against difficult disease targets will require the identification of new subunit vaccination strategies that can induce and maintain effective immune responses in humans. Here we report on a phase 1a clinical trial using the AMA1 antigen from the blood-stage Plasmodium falciparum malaria parasite delivered either as recombinant protein formulated with Alhydrogel adjuvant with and without CPG 7909, or using recombinant vectored vaccines--chimpanzee adenovirus ChAd63 and the orthopoxvirus MVA. A variety of promising "mixed-modality" regimens were tested. All volunteers were primed with ChAd63, and then subsequently boosted with MVA and/or protein-in-adjuvant using either an 8- or 16-week prime-boost interval. We report on the safety of these regimens, as well as the T cell, B cell, and serum antibody responses. Notably, IgG antibody responses primed by ChAd63 were comparably boosted by AMA1 protein vaccine, irrespective of whether CPG 7909 was included in the Alhydrogel adjuvant. The ability to improve the potency of a relatively weak aluminium-based adjuvant in humans, by previously priming with an adenoviral vaccine vector encoding the same antigen, thus offers a novel vaccination strategy for difficult or neglected disease targets when access to more potent adjuvants is not possible.

  8. Purified JC virus T antigen derived from insect cells preferentially interacts with binding site II of the viral core origin under replication conditions.

    Science.gov (United States)

    Bollag, B; Mackeen, P C; Frisque, R J

    1996-04-01

    The human polyomavirus JC virus (JCV) establishes persistent, asymptomatic infections in most individuals, but in severely immunocompromised hosts it may cause the fatal demyelinating brain disease progressive multifocal leukoencephalopathy. In cell culture JCV multiplies inefficiently and exhibits a narrow host range. This restricted behavior occurs, in part, at the level of DNA replication, which is regulated by JCV's multifunctional large tumor protein (TAg). To prepare purified JCV TAg (JCT) for biochemical analyses, the recombinant baculovirus B-JCT was generated by cotransfection of insect cells with wild-type baculovirus and the vector pVL-JCT(Int-) containing the JCT-coding sequence downstream of the efficient polyhedrin promoter. JCT expressed in infected cells was immunoaffinity purified using the anti-JCT monoclonal antibody PAb 2000. Characterization of the viral oncoprotein indicated that it exists in solution as a mixture of monomeric and oligomeric species. With the addition of ATP, the population of monomers decreased and that of hexamers and double hexamers increased. A DNA mobility shift assay indicated that origin binding occurred primarily with the double-hexamer form. A comparison of the specific DNA-binding activities of JCT and SV40 TAg (SVT) revealed that JCT generally exhibited greater affinity for binding site II relative to binding site I (B.S. I) of both viral origin regions, whereas SVT preferentially bound B.S. I. Furthermore, JCT bound nonviral DNA more efficiently than did SVT. These functional differences between the two TAgs may contribute to the reduced DNA replication potential of JCV in vitro, and to the virus' ability to establish persistent infections in vivo.

  9. Análisis de técnicas de recuperación antigénica para la detección inmunohistoquímica del virus de la diarrea viral bovina Analysis of antigen retrieval techniques for the immunohistochemical detection of the Bovine Viral Diarrhea virus

    Directory of Open Access Journals (Sweden)

    M.R. Marini

    2006-12-01

    Full Text Available En el presente trabajo se evaluaron diferentes métodos de recuperación antigénica para permitir la inmunodetección del virus de la Diarrea Viral Bovina (vDVB en materiales fijados con formol. Se analizó el efecto de la aplicación de digestión proteolítica (ficina, tripsina, pepsina, proteinasa K y su combinación con tratamiento en un horno microondas empleando diferentes concentraciones y tiempos de incubación para el anticuerpo primario. El tratamiento más efectivo fue el realizado con proteinasa K, utilizando diluciones de 1:30 para los anticuerpos primarios, con incubación durante toda la noche a temperatura ambiente. Concluimos que la fijación formólica afecta la antigenicidad del vDVB pero estos efectos pueden ser revertidos por digestión proteolítica específica permitiendo la utilización de la inmunohistoquímica como técnica de rutina para el diagnóstico de la enfermedad.In the present work different methods of antigen retrieval were evaluated to allow the immunodetection of the Bovine Viral Diarrhea virus (BVDv in materials fixed with formol. The effect of the application of proteolytic digestion was analyzed (ficin, trypsin, pepsin, proteinase K and its combination with treatment in a microwave oven using different concentrations and times of incubation for the primary antibody. The most effective treatment was the one carried out with proteinase K, using 1:30 dilution for the primary antibodies, with overnight incubation at room temperature. We conclude that the formol fixation affects the antigenicity of the BVDv but these effects can be reverted by specific proteolytic digestion allowing the use of the immunohistochemical routine technique for the diagnosis of the disease.

  10. Viral marketing

    OpenAIRE

    Král, Jiří

    2015-01-01

    Bachelor's Thesis deals with effective promotional tools called viral marketing. The main contribution of the thesis is the definition and history of viral marketing, making analysis of process of viral marketing, progresses definition and rules for creating a viral campaign. And also aspects are necessary for a successful viral spread. There are analysis of the characteristics of social media which are dividing according to the orientation and marketing tactics. Thesis is especially about so...

  11. Diagnóstico rápido de citomegalovirus (CMV en pacientes inmunocomprometidos mediante anticuerpos monoclonales que reconocen proteinas precoces virales Rapid diagnosis of cytomegalovirus infection in immunocompromised patients by using monoclonal antibodies against early viral antigens

    Directory of Open Access Journals (Sweden)

    Maritza Alvarez

    1989-06-01

    Full Text Available Se aplicó la técnica de detección de antigenos precoces fluorescentes (DAPF usando el anticuerpo monoclonal E-13 McAb, mediante el cual se lograron detectar 15 casos positivos a CMV de 75 muestras de orina o sangre ("buffy coat" tomadas de 52 pacientes inmunocomprometidos ingresados en el Instituto de Nefrología de ciudad Habana. Aplicando las técnicas clásicas de aislamiento en fibroblastos humanos diploides (MRC-5, se lograron aislar 12 cepas de CMV de casos previamente positivos por DAPF; lográndose además un aislamiento en una muestra reportada negativa por fluorescencia. Se observó una coincidencia de un 80% entre ambas técnicas. Se detectó la presencia de anticuerpos IgG contra CMV en todos los casos estudiados, utilizando para ello la técnica ELISA.A technique was applied to detect early fluorescent antigens (DEFA of cytomegalovirus (CMV using the E13 monoclonal antibodies in 52 immunocompromised patients hospitalized in the Nephrology Institute of Havana. Of the 75 urine or blood (buffy coat samples taken, 15 were found positive to CMV. Using classical diploide human fibroblast isolation technique, 12 CMV strains were isloation of previously detected positive samples by DEFA. In addition, CMV was isolated from one sample reported to be negative by DEFA. A coincidence of 80% was found between both techniques. With the ELISA test, all the sample studied have IgG antibodies to CMV.

  12. Small molecule inhibition of Epstein-Barr virus nuclear antigen-1 DNA binding activity interferes with replication and persistence of the viral genome.

    Science.gov (United States)

    Lee, Eun Kyung; Kim, Sun Young; Noh, Ka-Won; Joo, Eun Hye; Zhao, Bo; Kieff, Elliott; Kang, Myung-Soo

    2014-04-01

    The replication and persistence of extra chromosomal Epstein-Barr virus (EBV) episome in latently infected cells are primarily dependent on the binding of EBV-encoded nuclear antigen 1 (EBNA1) to the cognate EBV oriP element. In continuation of the previous study, herein we characterized EBNA1 small molecule inhibitors (H20, H31) and their underlying inhibitory mechanisms. In silico docking analyses predicted that H20 fits into a pocket in the EBNA1 DNA binding domain (DBD). However, H20 did not significantly affect EBNA1 binding to its cognate sequence. A limited structure-relationship study of H20 identified a hydrophobic compound H31, as an EBNA1 inhibitor. An in vitro EBNA1 EMSA and in vivo EGFP-EBNA1 confocal microscopy analysis showed that H31 inhibited EBNA1-dependent oriP sequence-specific DNA binding activity, but not sequence-nonspecific chromosomal association. Consistent with this, H31 repressed the EBNA1-dependent transcription, replication, and persistence of an EBV oriP plasmid. Furthermore, H31 induced progressive loss of EBV episome. In addition, H31 selectively retarded the growth of EBV-infected LCL or Burkitt's lymphoma cells. These data indicate that H31 inhibition of EBNA1-dependent DNA binding decreases transcription from and persistence of EBV episome in EBV-infected cells. These new compounds might be useful probes for dissecting EBNA1 functions in vitro and in vivo.

  13. Association of cytotoxic T-lymphocyte antigen 4 genetic polymorphism, hepatitis C viral infection and B-cell non-Hodgkin lymphoma: an Egyptian study.

    Science.gov (United States)

    Khorshied, Mervat Mamdooh; Gouda, Heba Mahmoud; Khorshid, Ola M Reda

    2014-05-01

    Abstract Genetic and environmental factors are involved in the pathogenesis of non-Hodgkin lymphoma (NHL). The present study aimed to investigate the association between cytotoxic T-lymphocyte antigen 4 (CTLA-4) genetic polymorphism, hepatitis C virus (HCV) infection and B-cell NHL risk in Egypt. Genotyping of CTLA-4 single nucleotide polymorphisms (SNPs) was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay for 181 adult patients with B-NHL and 200 controls. Our study revealed that CTLA-4 + 49 A/G polymorphism conferred increased risk of B-NHL (odds ratio [OR] = 1.7, 95% confidence interval [CI] = 1.36-2.565). The prevalence of HCV infection in individuals harboring the mutant genotype + 49 A/G and - 318 C/T SNPs was higher in patients with B-NHL and was associated with increased risk of B-NHL (OR = 2.79, 95% CI = 1.24-6.93 for + 49 A/G and OR = 3.9, 95% CI = 1.01-15.98 for - 318 C/T). In conclusion, some SNPs of CTLA-4 are genetic risk factors for B-NHL. Moreover, this study identified an association of CTLA-4 + 49 A/G and - 318 C/T promoter polymorphisms with HCV infection.

  14. Epstein–Barr virus nuclear antigen 3C interact with p73: Interplay between a viral oncoprotein and cellular tumor suppressor

    Energy Technology Data Exchange (ETDEWEB)

    Sahu, Sushil Kumar; Mohanty, Suchitra; Kumar, Amit [Division of Infectious Disease Biology, Institute of Life Sciences, Nalco Square, Chandrasekharpur, Bhubaneswar 751023 (India); Kundu, Chanakya N. [School of Biotechnology, KIIT University, Bhubaneswar (India); Verma, Subhash C. [Department of Microbiology and Immunology, University of Nevada, School of Medicine, Reno, NV 89557 (United States); Choudhuri, Tathagata, E-mail: tatha@ils.res.in [Division of Infectious Disease Biology, Institute of Life Sciences, Nalco Square, Chandrasekharpur, Bhubaneswar 751023 (India); Department of Biotechnology, Siksha Bhavana, Visva Bharati, Santiniketan, Bolpur (India)

    2014-01-05

    The p73 protein has structural and functional homology with the tumor suppressor p53, which plays an important role in cell cycle regulation, apoptosis, and DNA repair. The p73 locus encodes both a tumor suppressor (TAp73) and a putative oncogene (ΔNp73). p73 May play a significant role in p53-deficient lymphomas infected with Epstein–Barr virus (EBV). EBV produces an asymptomatic infection in the majority of the global population, but it is associated with several human B-cell malignancies. The EBV-encoded Epstein–Barr virus nuclear antigen 3C (EBNA3C) is thought to disrupt the cell cycle checkpoint by interacting directly with p53 family proteins. Doxorubicin, a commonly used chemotherapeutic agent, induces apoptosis through p53 and p73 signaling such that the lowΔNp73 level promotes the p73-mediated intrinsic pathway of apoptosis. In this report, we investigated the mechanism by which EBV infection counters p73α-induced apoptosis through EBNA3C. - Highlights: • EBV-encoded EBNA3C suppresses doxorubicin-induced apoptosis in B-cell lymphomas. • EBNA3C binds to p73 to suppress its apoptotic effect. • EBNA3C maintains latency by regulating downstream mitochondrial pathways.

  15. Viral encephalitis

    Directory of Open Access Journals (Sweden)

    Marcus Tulius T Silva

    2013-09-01

    Full Text Available While systemic viral infections are exceptionally common, symptomatic viral infections of the brain parenchyma itself are very rare, but a serious neurologic condition. It is estimated that viral encephalitis occurs at a rate of 1.4 cases per 100.000 inhabitants. Geography is a major determinant of encephalitis caused by vector-borne pathogens. A diagnosis of viral encephalitis could be a challenge to the clinician, since almost 70% of viral encephalitis cases are left without an etiologic agent identified. In this review, the most common viral encephalitis will be discussed, with focus on ecology, diagnosis, and clinical management.

  16. Species-specific and cross-reactive IgG1 antibody binding to viral capsid protein 1 (VP1 antigens of human rhinovirus species A, B and C.

    Directory of Open Access Journals (Sweden)

    Jua Iwasaki

    Full Text Available BACKGROUND: Human rhinoviruses (HRV are associated with upper and lower respiratory illnesses, including severe infections causing hospitalization in both children and adults. Although the clinical significance of HRV infections is now well established, no detailed investigation of the immune response against HRV has been performed. The purpose of this study was to assess the IgG1 antibody response to the three known HRV species, HRV-A, -B and -C in healthy subjects. METHODS: Recombinant polypeptides of viral capsid protein 1 (VP1 from two genotypes of HRV-A, -B and -C were expressed as glutathione S-transferase (GST fusion proteins and purified by affinity and then size exclusion chromatography. The presence of secondary structures similar to the natural antigens was verified by circular dichroism analysis. Total and species-specific IgG1 measurements were quantitated by immunoassays and immunoabsorption using sera from 63 healthy adults. RESULTS: Most adult sera reacted with the HRV VP1 antigens, at high titres. As expected, strong cross-reactivity between HRV genotypes of the same species was found. A high degree of cross-reactivity between different HRV species was also evident, particularly between HRV-A and HRV-C. Immunoabsorption studies revealed HRV-C specific titres were markedly and significantly lower than the HRV-A and HRV-B specific titres (P<0.0001. A truncated construct of HRV-C VP1 showed greater specificity in detecting anti-HRV-C antibodies. CONCLUSIONS: High titres of IgG1 antibody were bound by the VP1 capsid proteins of HRV-A, -B and -C, but for the majority of people, a large proportion of the antibody to HRV-C was cross-reactive, especially to HRV-A. The improved specificity found for the truncated HRV-C VP1 indicates species-specific and cross-reactive regions could be defined.

  17. Evaluation of the Architect Epstein-Barr Virus (EBV) viral capsid antigen (VCA) IgG, VCA IgM, and EBV nuclear antigen 1 IgG chemiluminescent immunoassays for detection of EBV antibodies and categorization of EBV infection status using immunofluorescence assays as the reference method.

    Science.gov (United States)

    Corrales, Isabel; Giménez, Estela; Navarro, David

    2014-05-01

    Commercial immunoassays for detecting IgG and IgM antibodies against Epstein-Barr virus (EBV), viral capsid antigens (VCA), and IgGs toward EBV nuclear antigen-1 (EBNA-1) are routinely used in combination to categorize EBV infection status. In this study, we evaluated the performances of the Architect EBV VCA IgG, VCA IgM, and EBNA-1 IgG chemiluminescent microparticle assays (CMIAs) in EBV serological analyses using indirect immunofluorescence assays and anticomplement immunofluorescence assays as the reference methods for VCA IgG, VCA IgM, and EBNA-1 IgG antibody detection, respectively. A total of 365 serum samples representing different EBV serological profiles were included in this study. The κ values (concordances between the results) obtained in the Architect CMIA and those in the reference assays were 0.905 (P EBV infection, and 92.42% and 97.82% for diagnosing the absence of an EBV infection. In summary, we demonstrated that the Architect EBV antibody panel performs very well for EBV antibody detection and correctly categorizes clinically relevant EBV infection states.

  18. Binding of the heterogeneous ribonucleoprotein K (hnRNP K to the Epstein-Barr virus nuclear antigen 2 (EBNA2 enhances viral LMP2A expression.

    Directory of Open Access Journals (Sweden)

    Henrik Gross

    Full Text Available The Epstein-Barr Virus (EBV -encoded EBNA2 protein, which is essential for the in vitro transformation of B-lymphocytes, interferes with cellular processes by binding to proteins via conserved sequence motifs. Its Arginine-Glycine (RG repeat element contains either symmetrically or asymmetrically di-methylated arginine residues (SDMA and ADMA, respectively. EBNA2 binds via its SDMA-modified RG-repeat to the survival motor neurons protein (SMN and via the ADMA-RG-repeat to the NP9 protein of the human endogenous retrovirus K (HERV-K (HML-2 Type 1. The hypothesis of this work was that the methylated RG-repeat mimics an epitope shared with cellular proteins that is used for interaction with target structures. With monoclonal antibodies against the modified RG-repeat, we indeed identified cellular homologues that apparently have the same surface structure as methylated EBNA2. With the SDMA-specific antibodies, we precipitated the Sm protein D3 (SmD3 which, like EBNA2, binds via its SDMA-modified RG-repeat to SMN. With the ADMA-specific antibodies, we precipitated the heterogeneous ribonucleoprotein K (hnRNP K. Specific binding of the ADMA- antibody to hnRNP K was demonstrated using E. coli expressed/ADMA-methylated hnRNP K. In addition, we show that EBNA2 and hnRNP K form a complex in EBV- infected B-cells. Finally, hnRNP K, when co-expressed with EBNA2, strongly enhances viral latent membrane protein 2A (LMP2A expression by an unknown mechanism as we did not detect a direct association of hnRNP K with DNA-bound EBNA2 in gel shift experiments. Our data support the notion that the methylated surface of EBNA2 mimics the surface structure of cellular proteins to interfere with or co-opt their functional properties.

  19. Binding of the heterogeneous ribonucleoprotein K (hnRNP K) to the Epstein-Barr virus nuclear antigen 2 (EBNA2) enhances viral LMP2A expression.

    Science.gov (United States)

    Gross, Henrik; Hennard, Christine; Masouris, Ilias; Cassel, Christian; Barth, Stephanie; Stober-Grässer, Ute; Mamiani, Alfredo; Moritz, Bodo; Ostareck, Dirk; Ostareck-Lederer, Antje; Neuenkirchen, Nils; Fischer, Utz; Deng, Wen; Leonhardt, Heinrich; Noessner, Elfriede; Kremmer, Elisabeth; Grässer, Friedrich A

    2012-01-01

    The Epstein-Barr Virus (EBV) -encoded EBNA2 protein, which is essential for the in vitro transformation of B-lymphocytes, interferes with cellular processes by binding to proteins via conserved sequence motifs. Its Arginine-Glycine (RG) repeat element contains either symmetrically or asymmetrically di-methylated arginine residues (SDMA and ADMA, respectively). EBNA2 binds via its SDMA-modified RG-repeat to the survival motor neurons protein (SMN) and via the ADMA-RG-repeat to the NP9 protein of the human endogenous retrovirus K (HERV-K (HML-2) Type 1). The hypothesis of this work was that the methylated RG-repeat mimics an epitope shared with cellular proteins that is used for interaction with target structures. With monoclonal antibodies against the modified RG-repeat, we indeed identified cellular homologues that apparently have the same surface structure as methylated EBNA2. With the SDMA-specific antibodies, we precipitated the Sm protein D3 (SmD3) which, like EBNA2, binds via its SDMA-modified RG-repeat to SMN. With the ADMA-specific antibodies, we precipitated the heterogeneous ribonucleoprotein K (hnRNP K). Specific binding of the ADMA- antibody to hnRNP K was demonstrated using E. coli expressed/ADMA-methylated hnRNP K. In addition, we show that EBNA2 and hnRNP K form a complex in EBV- infected B-cells. Finally, hnRNP K, when co-expressed with EBNA2, strongly enhances viral latent membrane protein 2A (LMP2A) expression by an unknown mechanism as we did not detect a direct association of hnRNP K with DNA-bound EBNA2 in gel shift experiments. Our data support the notion that the methylated surface of EBNA2 mimics the surface structure of cellular proteins to interfere with or co-opt their functional properties.

  20. Recombinant viral-vectored vaccines expressing Plasmodium chabaudi AS apical membrane antigen 1: mechanisms of vaccine-induced blood-stage protection.

    Science.gov (United States)

    Biswas, Sumi; Spencer, Alexandra J; Forbes, Emily K; Gilbert, Sarah C; Holder, Anthony A; Hill, Adrian V S; Draper, Simon J

    2012-05-15

    Apical membrane Ag 1 (AMA1) is one of the leading candidate Ags for inclusion in a subunit vaccine against blood-stage malaria. However, the efficacy of Ab-inducing recombinant AMA1 protein vaccines in phase IIa/b clinical trials remains disappointing. In this article, we describe the development of recombinant human adenovirus serotype 5 and modified vaccinia virus Ankara vectors encoding AMA1 from the Plasmodium chabaudi chabaudi strain AS. These vectors, when used in a heterologous prime-boost regimen in BALB/c mice, are capable of inducing strong transgene-specific humoral and cellular immune responses. We show that this vaccination regimen is protective against a nonlethal P. chabaudi chabaudi strain AS blood-stage challenge, resulting in reduced peak parasitemias. The role of vaccine-induced, AMA1-specific Abs and T cells in mediating the antiparasite effect was investigated by in vivo depletion of CD4(+) T cells and adoptive-transfer studies into naive and immunodeficient mice. Depletion of CD4(+) T cells led to a loss of vaccine-induced protection. Adoptive-transfer studies confirmed that efficacy is mediated by both CD4(+) T cells and Abs functioning in the context of an intact immune system. Unlike previous studies, these results confirm that Ag-specific CD4(+) T cells, induced by a clinically relevant vaccine-delivery platform, can make a significant contribution to vaccine blood-stage efficacy in the P. chabaudi model. Given that cell-mediated immunity may also contribute to parasite control in human malaria, these data support the clinical development of viral-vectored vaccines that induce both T cell and Abs against Plasmodium falciparum blood-stage malaria Ags like AMA1.

  1. Treatment of viral encephalitis.

    Science.gov (United States)

    Domingues, Renan Barros

    2009-03-01

    Several viruses may cause central nervous system diseases with a broad range of clinical manifestations. The time course of the viral encephalitis can be acute, subacute, or chronic. Pathologically there are encephalitis with direct viral entry into the CNS in which brain parenchyma exhibits neuronal damaging and viral antigens and there are postinfectious autoimmune encephalitis associated with systemic viral infections with brain tissue presenting perivascular aggregation of immune cells and myelin damaging. Some virus affect previously healthy individuals while others produce encephalitis among imunocompromised ones. Factors such evolving lifestyles and ecological changes have had a considerable impact on the epidemiology of some viral encephalitis [e.g. West-Nile virus, and Japanese B virus]. Citomegalovirus and JC virus are examples of infections of the brain that have been seen more frequently because they occur in immunocompromised patients. In the other hand many scientific achievements in neuroimaging, molecular diagnosis, antiviral therapy, immunomodulatory treatments, and neurointensive care have allowed more precise and earlier diagnoses and more efficient treatments, resulting in improved outcomes. In this article, we will present the current drug options in the management of the main acute and chronic viral infection of the central nervous system of immunocompetent and immunocompromised adults, focusing on drugs mechanisms of action, efficacy, and side effects. The early diagnosis and correct management of such diseases can reduce mortality and neurological sequelae; however, even with recent treatment advances, potentially devastating outcomes are still possible.

  2. X-ray diffraction analysis of crystals from the human major histocompatibility antigen HLA-B*2706 in complex with a viral peptide and with a self-peptide

    Energy Technology Data Exchange (ETDEWEB)

    Zawacka, Anna [Institut für Immungenetik, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum, Humboldt-Universität zu Berlin, Spandauer Damm 130, 14050 Berlin (Germany); Loll, Bernhard; Biesiadka, Jacek; Saenger, Wolfram [Institut für Chemie und Biochemie/Kristallographie, Freie Universität Berlin, Takustrasse 6, 14195 Berlin (Germany); Uchanska-Ziegler, Barbara; Ziegler, Andreas, E-mail: andreas.ziegler@charite.de [Institut für Immungenetik, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum, Humboldt-Universität zu Berlin, Spandauer Damm 130, 14050 Berlin (Germany)

    2005-12-01

    The crystallization of HLA-B*2706 in complex with two peptides is reported. The human leukocyte antigen (HLA) alleles HLA-B*2704 and HLA-B*2706 show an ethnically restricted distribution and are differentially associated with ankylosing spondylitis, with HLA-B*2706 lacking association with this autoimmune disease. However, the products of the two alleles differ by only two amino acids, at heavy-chain residues 114 (His in HLA-B*2704; Asp in HLA-B*2706) and 116 (Asp in HLA-B*2704; Tyr in HLA-B*2706). Both residues could be involved in contacting amino acids of a bound peptide, suggesting that peptides presented by these subtypes play a role in disease pathogenesis. Two HLA-B*2706–peptide complexes were crystallized using the hanging-drop vapour-diffusion method with PEG as precipitant. Data sets were collected to resolutions of 2.70 Å (viral peptide pLMP2, RRRWRRLTV; space group P2{sub 1}2{sub 1}2{sub 1}) and 1.83 Å (self-peptide pVIPR, RRKWRRWHL; space group P2{sub 1}). Using HLA-B*2705 complexed with the pGR peptide (RRRWHRWRL) as a search model, unambiguous molecular-replacement solutions were found for both HLA-B*2706 complexes.

  3. Myosins 1 and 6, myosin light chain kinase, actin and microtubules cooperate during antibody-mediated internalisation and trafficking of membrane-expressed viral antigens in feline infectious peritonitis virus infected monocytes.

    Science.gov (United States)

    Dewerchin, Hannah L; Desmarets, Lowiese M; Noppe, Ytse; Nauwynck, Hans J

    2014-02-12

    Monocytes infected with feline infectious peritonitis virus, a coronavirus, express viral proteins in their plasma membranes. Upon binding of antibodies, these proteins are quickly internalised through a new clathrin- and caveolae-independent internalisation pathway. By doing so, the infected monocytes can escape antibody-dependent cell lysis. In the present study, we investigated which kinases and cytoskeletal proteins are of importance during internalisation and subsequent intracellular transport. The experiments showed that myosin light chain kinase (MLCK) and myosin 1 are crucial for the initiation of the internalisation. With co-localisation stainings, it was found that MLCK and myosin 1 co-localise with antigens even before internalisation started. Myosin 6 co-localised with the internalising complexes during passage through the cortical actin, were it might play a role in moving or disintegrating actin filaments, to overcome the actin barrier. One minute after internalisation started, vesicles had passed the cortical actin, co-localised with microtubules and association with myosin 6 was lost. The vesicles were further transported over the microtubules and accumulated at the microtubule organising centre after 10 to 30 min. Intracellular trafficking over microtubules was mediated by MLCK, myosin 1 and a small actin tail. Since inhibiting MLCK with ML-7 was so efficient in blocking the internalisation pathway, this target can be used for the development of a new treatment for FIPV.

  4. Viral marketing

    OpenAIRE

    BLÁHOVÁ, Adéla

    2012-01-01

    The aim of my thesis is to provide a comprehensive overview of the viral marketing and to analyze selected viral campaigns. There is a description of advantages and disadvantages of this marketing tool. In the end I suggest for which companies viral marketing is an appropriate form of the promotion.

  5. Dengue viruses cluster antigenically but not as discrete serotypes

    NARCIS (Netherlands)

    L. Katzelnick (Leah); J.M. Fonville (Judith); G.D. Gromowski (Gregory D.); J.B. Arriaga (Jose Bustos); A. Green (Angela); S.L. James (Sarah ); L. Lau (Louis); M. Montoya (Magelda); C. Wang (Chunling); L.A. Van Blargan (Laura A.); C.A. Russell (Colin); H.M. Thu (Hlaing Myat); T.C. Pierson (Theodore C.); P. Buchy (Philippe); J.G. Aaskov (John G.); J.L. Muñoz-Jordán (Jorge L.); N. Vasilakis (Nikos); R.V. Gibbons (Robert V.); R.B. Tesh (Robert B.); A.D.M.E. Osterhaus (Albert); R.A.M. Fouchier (Ron); A. Durbin (Anna); C.P. Simmons (Cameron P.); E.C. Holmes (Edward C.); E. Harris (Eva); S.S. Whitehead (Stephen S.); D.J. Smith (Derek James)

    2015-01-01

    textabstractThe four genetically divergent dengue virus (DENV) types are traditionally classified as serotypes. Antigenic and genetic differences among the DENV types influence disease outcome, vaccine-induced protection, epidemic magnitude, and viral evolution.We scharacterized antigenic diversity

  6. Expression, purification and preliminary X-ray crystallographic analysis of the human major histocompatibility antigen HLA-B*1402 in complex with a viral peptide and with a self-peptide

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Pravin [Institut für Immungenetik, Charité - Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, Thielallee 73, 14195 Berlin (Germany); Vahedi-Faridi, Ardeschir [Institut für Chemie und Biochemie/Kristallographie, Freie Universität Berlin, Takustrasse 6, 14195 Berlin (Germany); Merino, Elena; López de Castro, José A. [Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Cientificas, Universidad Autónoma de Madrid, Facultad de Ciencias, Universidad Autónoma, 28049 Madrid (Spain); Volz, Armin; Ziegler, Andreas [Institut für Immungenetik, Charité - Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, Thielallee 73, 14195 Berlin (Germany); Saenger, Wolfram, E-mail: saenger@chemie.fu-berlin.de [Institut für Chemie und Biochemie/Kristallographie, Freie Universität Berlin, Takustrasse 6, 14195 Berlin (Germany); Uchanska-Ziegler, Barbara, E-mail: saenger@chemie.fu-berlin.de [Institut für Immungenetik, Charité - Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, Thielallee 73, 14195 Berlin (Germany)

    2007-07-01

    The crystallization of HLA-B*1402 in complex with two peptides is reported. The product of the human major histocompatibility (HLA) class I allele HLA-B*1402 only differs from that of allele HLA-B*1403 at amino-acid position 156 of the heavy chain (Leu in HLA-B*1402 and Arg in HLA-B*1403). However, both subtypes are known to be differentially associated with the inflammatory rheumatic disease ankylosing spondylitis (AS) in black populations in Cameroon and Togo. HLA-B*1402 is not associated with AS, in contrast to HLA-B*1403, which is associated with this disease in the Togolese population. The products of these alleles can present peptides with Arg at position 2, a feature shared by a small group of other HLA-B antigens, including HLA-B*2705, the prototypical AS-associated subtype. Complexes of HLA-B*1402 with a viral peptide (RRRWRRLTV, termed pLMP2) and a self-peptide (IRAAPPPLF, termed pCatA) were prepared and were crystallized using polyethylene glycol as precipitant. The complexes crystallized in space groups P2{sub 1} (pLMP2) and P2{sub 1}2{sub 1}2{sub 1} (pCatA) and diffracted synchrotron radiation to 2.55 and 1.86 Å resolution, respectively. Unambiguous solutions for both data sets were obtained by molecular replacement using a peptide-complexed HLA-B*2705 molecule (PDB code) as a search model.

  7. Viral induced demyelination.

    Science.gov (United States)

    Stohlman, S A; Hinton, D R

    2001-01-01

    oligodendroglia or the myelin sheath; or 4) infection initiates activation of an immune response specific for either oligodendroglia or myelin components. Virus-induced inflammation may be associated with the processing of myelin or oligodendroglial components and their presentation to the host's own T cell compartment. Alternatively, antigenic epitopes derived from the viral proteins may exhibit sufficient homology to host components that the immune response to the virus activates autoreactive T cells, i.e. molecular mimicry. Although it is not clear that each of these potential mechanisms participates in the pathogenesis of human demyelinating disease, analysis of the diverse demyelinating viral infections of both humans and rodents provides examples of many of these potential mechanisms.

  8. Effect of cell culture system on the production of human viral antigens Efeito do sistema de cultura celular na produção de antígenos virais humanos

    Directory of Open Access Journals (Sweden)

    Ronaldo Zucatelli Mendonça

    2004-06-01

    Full Text Available A comparative study was performed in the production of different viral antigens by using microcarrier systems and traditional systems. Vero, BHK and MA 104 cells were cultivated in microcarriers (2mg/ml using a bioreactor with a working capacity of 3.7 liters, in parallel with conventional Roux bottles. After four days (BHK cells, and seven days of culture (Vero and MA-104 cells, the cells were infected with 0.1 MOI (multiplicity of infection of rabies virus, measles virus, poliovirus and rotavirus. The yields of the cells and virus in microcarriers and in the conventional system were determined. It was observed that in the microcarrier system, an average increase of twenty-fold more cells/ml was obtained in relation to the conventional monolayer culture, using Roux bottle. On the other hand, cells grown in Roux bottles presented 1.3 to 6.7 more viruses/ml culture than those in the microcarrier systems. However, the overall data showed that yieldings, in terms of viruses per batch, were statistically similar for both systems (p > 0.05. The amount of viral antigen production seems to depend not only on cell concentration, but also on other culture factors such as the characteristic of the cell-growth surface. Thus, the present findings provide a baseline for further improvements and strategies to be established for a scaling-up virus production since depending on the type of virus the optimal conditions found for a small-scale virus production seem unsuitable for large-scale production, requiring new standardization and evaluation.Foi realizado estudo comparativo na produção de diferentes antígenos virais usando sistema de microcarregador e sistema tradicional. Células Vero, BHK e MA-104 foram cultivadas em microcarregadores (2mg/ml utilizando-se biorreatores com capacidade de 3,7 litros e, em paralelo, no sistema convencional com garrafas Roux. Após quatro dias de cultura para as células BHK e sete dias para as células Vero e MA-104, as c

  9. Analysis of Mmultiple Viral Antigens in Pediatric Patients Detection Result by Direct Immunofluorescence Method%直接免疫荧光法分析儿童呼吸道病毒的分布

    Institute of Scientific and Technical Information of China (English)

    冯辉; 刘永林; 陈益民

    2015-01-01

    Purpose] To detect respiratory virus antigen by direct immunofluorescence method and provide evidence for early diagnosis of children with viral infection of the respiratory tract disease.[Methods] Select 398 cases of respiratory tract infection in hospitalized children, pharynx in exfoliated cells in respiratory syncytial virus by direct immunofluorescence(RSV), adenovirus(ADV), influenza virus type A(IFVA),influenza virus type B(IFVB), parainfluenza virus type 1(PIV1), parainfluenza virus type 2(PIV2) and parainflue-Nza virus type 3(PIV3) of 7 common viral antigens were detected, and carried on statistics analysis.[Results] In 398 cases of children with respiratory tract infection, 91 cases were positive, the positive rate was 22.86%. The highest for respiratory syncytial virus in 37 cases(40.66%) followed by parainfluenza virus type 3 in 19 cases(20.88%), influenza virus type B in 14 cases(15.38%); The positive rates of acute tonsillitis, capillary bronchitis, pneumonia, acute bronchitis and upper respiratory were 46.67%(14/30),40.00%(20/50), 26.67%(40/150), 18.42%(7/38), 7.69%(10/130) respectively; With the growth of age, the respiratory tract virus infection rate gradually decreased(P<0.05), one year old the viral infection rate was 76.92%;it occurred in the winter season of respiratory tract infection in children .[Conclusion] The main virus in children with acute respiratory infection in the local area is RSV. Virus infection decreases with the increase of age, treatment should be careful in the use of antibiotics.%[目的]采用直接免疫荧光法检测呼吸道病毒抗原,为儿童呼吸道病毒感染诊断提供帮助。[方法]选择398例呼吸道感染的住院患儿,采用直接免疫荧光法对咽部脱落细胞中的呼吸道合胞病毒(respiratory syncytial virus,RSV)、腺病毒(adenovirus,ADV)、流感病毒A型(the influenza virus type A, IFVA)、流感病毒B型(the influenza virus type B,IFVB)、副流感病毒1

  10. Analysis of Epstein-Barr viral DNA load, EBV-LMP2 specific cytotoxic T-lymphocytes and levels of CD4+CD25+T cells in patients with nasopharyngeal carcinomas positive for IgA antibody to EBV viral capsid antigen

    Institute of Scientific and Technical Information of China (English)

    MO Wu-ning; TANG An-zhou; ZHOU Ling; HUANG Guang-wu; WANG Zhan; ZENG Yi

    2009-01-01

    Background Epstein-Barr virus (EBV) is a herpesvirus commonly associated with several malignant diseases including nasopharyngeal carcinoma (NPC), which is a common cancer in Southeastem Asia. Previous studies showed that plasma levels of EBV-DNA might be a sensitive and reliable biomarker for the diagnosis, staging and evaluating of therapy for NPC. There are a few analyses of the levels of EBV-latent membrane protein 2 (LMP2)-specific cytotoxic T-lymphocytes (CTLs) in patients with NPC. This study was conducted to investigate the levels of EBV-LMP2-specific CTLs, EBV-DNA load and the level of CD4+CD25+T cells in such patients.Methods From February 2006 to April 2006, 62 patients with NPC, 40 healthy virus carders positive for EBV viral capsid antigen (EBV-IgA-VCA) and 40 controls were enrolled in the study. We used a highly sensitive ELISPOT assay,real-time polymerase chain reaction (PCR) and flow cytometry to measure the EBV-LMP2-specific CTL response, the EBV DNA load and the level of CD4+CD25+T cells, respectively.Results The EBV-LMP2-specific CTL responses of the samples from the control, healthy virus carders and patients with NPC were significantly different from the LMP2 epitopes, with the control and healthy virus carder samples displaying a stronger response in three cases. There were significant differences in EBV DNA load in serum between NPC and the healthy groups; patients with NPC at stages Ⅲ or Ⅳ had significantly higher viral loads compared with those at stages Ⅰ or Ⅱ. A significantly higher percentage of CD4+CD25+ T lymphocytes were detected in the patients, compared with healthy virus carriers and healthy controls. Moreover, patients with advanced stages of NPC (Ⅲ and Ⅲ) had significantly higher percentages than the patients with early stages (Ⅰ and Ⅱ).Conclusions Patients with NPC are frequently unable to establish or maintain sufficient immunosurveillance to control proliferating B cells harboring EBV and to destroy the tumor

  11. Viral information.

    Science.gov (United States)

    Rohwer, Forest; Barott, Katie

    2013-03-01

    Viruses are major drivers of global biogeochemistry and the etiological agents of many diseases. They are also the winners in the game of life: there are more viruses on the planet than cellular organisms and they encode most of the genetic diversity on the planet. In fact, it is reasonable to view life as a viral incubator. Nevertheless, most ecological and evolutionary theories were developed, and continue to be developed, without considering the virosphere. This means these theories need to be to reinterpreted in light of viral knowledge or we need to develop new theory from the viral point-of-view. Here we briefly introduce our viral planet and then address a major outstanding question in biology: why is most of life viral? A key insight is that during an infection cycle the original virus is completely broken down and only the associated information is passed on to the next generation. This is different for cellular organisms, which must pass on some physical part of themselves from generation to generation. Based on this premise, it is proposed that the thermodynamic consequences of physical information (e.g., Landauer's principle) are observed in natural viral populations. This link between physical and genetic information is then used to develop the Viral Information Hypothesis, which states that genetic information replicates itself to the detriment of system energy efficiency (i.e., is viral in nature). Finally, we show how viral information can be tested, and illustrate how this novel view can explain existing ecological and evolutionary theories from more fundamental principles.

  12. VIRAL MARKETING

    OpenAIRE

    OLENTSOVA Y.A.

    2016-01-01

    Abstract This project seeks to investigate how the company Gitz can create awareness towards their brand by using viral marketing. To do this we analyze which elements of viral marketing the company can use, to reach their goal. In order to utilize the selected tools of viral marketing best possible, we need to figure out the company’s customer segment and figure out how to reach that segment. This has been done with the use of Henrik Dahl’s Minerva-model that divides the population into f...

  13. Diversidade antigênica de amostras do vírus da diarréia viral bovina isoladas no Brasil: implicações para o diagnóstico e estratégias de imunização Antigenic diversity of Brazilian isolates of bovine viral diarrhea virus (BVDV: implications for diagnosis and immunization strategies

    Directory of Open Access Journals (Sweden)

    E.F. Flores

    2000-02-01

    Full Text Available Seqüenciamento e análise filogenética de 17 amostras do vírus da diarréia viral bovina (BVDV isoladas no Brasil identificaram quatro amostras (23,5% do genótipo 1a (BVDV-1a, nove amostras (52,9% do genótipo 1b (BVDV tipo 1b e quatro amostras (23,5% do genótipo 2 (BVDV tipo 2. As amostras brasileiras de BVDV tipo 2 apresentaram-se genotipicamente distintas dos BVDV tipo 2 até então identificados na América do Norte e Europa, sugerindo pertencerem a um novo subgenótipo. A caracterização antigênica dessas amostras por neutralização cruzada revelou reatividade sorológica muito reduzida com cepas vacinais do BVDV. O anti-soro produzido contra três cepas vacinais do BVDV apresentou atividade neutralizante muito reduzida contra várias amostras brasileiras de BVDV tipos 1 e 2. Diferenças de até 128 vezes nos títulos de anticorpos neutralizantes foram observadas entre cepas vacinais e amostras brasileiras do BVDV. Nos testes de soroneutralização (SN contra o vírus dos tipos 1 e 2, de 1134 amostras testadas, 280 (24,7% possuiam anticorpos neutralizantes anti-BVDV e dessas, 215 (76,8% apresentaram atividade neutralizante contra ambos os vírus, 37 (13,2% reagiram apenas contra o BVDV tipo 2 e 28 amostras (10% foram positivas apenas contra o BVDV tipo 1. Esses resultados demonstram que testes de SN utilizando vírus de apenas um genótipo podem resultar em um número significativo de falsos-negativos e indica a necessidade da formulação de vacinas com amostras locais de BVDV e/ou contendo vírus dos dois genótipos.Nucleotide sequencing and phylogenetic analysis of 17 Brazilian isolates of bovine viral diarrhea virus (BVDV identified four isolates (23.5% belonging to genotype 1a (BVDV-1a, nine isolates (52.9% of the genotype 1b (BVDV-1b and four isolates (23.5% belonging to genotype 2 (BVDV-2. The Brazilian BVDV type 2 isolates were shown to be genotypically different from the BVDV type 2 identified so far in North America and

  14. Detection of PMTV Using Polyclonal Antibodies Raised Against a Capsid-Specific Peptide Antigen / Detección de PMTV Utilizando Anticuerpos Policlonales Contra un Péptido Antigénico Derivado de la Cápside Viral

    Directory of Open Access Journals (Sweden)

    Yuliana Gallo García

    2013-12-01

    Full Text Available Potato mop-top virus (PMTV; genus Pomovirus;family Virgaviridae is the causing agent of the spraing disease in potato (Solanum tuberosum. PMTV is transmitted by Spongospora subterranea f. sp. subterranea (Sss. This disease has a widespread distribution in potato growing regions around the world. The possibility of obtaining strain specific antibodies at low cost can greatly increase the sensitivity and use of serological tests in seed certification programs, plant breeding and quarantine regulations to avoid dissemination of this injurious virus. This work presents an alternative procedure for the production of PMTV specific antibodies useful in serological test such as ELISAand lateral flow. In contrast to standard methods requiring theisolation of viral particles or expression of recombinant capsid, this method uses peptides mimicking the N-terminal region of PMTV capsid protein as antigen for the production of specific polyclonal antibodies. The antibodies were tested against bait plants grown in soil infested with viruliferous Sss, as well as potato plants obtained from naturally Sss infested fields in Colombia. PMTV was detected in 9/14 and 24/28 foliage samples of N. benthamiana and S. phureja, respectively. In the case of field plants, the virus wasdetected in eight out of 12 root tissues evaluated. The minimumpeptide concentration detected by ELISA was of the order of 0.1 nM. / Potato mop-top virus (PMTV; género Pomovirus; familia Virgaviridae es transmitido por Spongospora subterranea f. sp. subterranea (Sss, agente causal de la sarna polvosa de la papa. Esta enfermedad tiene una amplia distribución en las regiones cultivadoras de papa alrededor del mundo. La posibilidad de obtener anticuerpos específicos contra cepas de este virus, puede incrementar la sensibilidad y la utilización de pruebas serológicas en programas de certificación de semilla, mejoramiento genético y regulaciones cuarentenarias que eviten su diseminaci

  15. Viral arthritis

    Science.gov (United States)

    Infectious arthritis - viral ... Arthritis may be a symptom of many virus-related illnesses. It usually disappears on its own without ... the rubella vaccine, only a few people develop arthritis. No risk factors are known.

  16. Viral disease

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    2010286 The development and application of influenza A virus antigen-detecting enzyme linked,immunosorbent assay kit. WANG Changbing(王长兵),et al. Centr Lab,Children’s Hosp,Guangzhou Women & Children’s Med Center,Guangzhou 510120. Chin J Infect Dis 2010;28(4):204-208. Objective To develop and verify an influenza A virus antigen-detecting kit

  17. Viral quasispecies.

    Science.gov (United States)

    Andino, Raul; Domingo, Esteban

    2015-05-01

    New generation sequencing is greatly expanding the capacity to examine the composition of mutant spectra of viral quasispecies in infected cells and host organisms. Here we review recent progress in the understanding of quasispecies dynamics, notably the occurrence of intra-mutant spectrum interactions, and implications of fitness landscapes for virus adaptation and de-adaptation. Complementation or interference can be established among components of the same mutant spectrum, dependent on the mutational status of the ensemble. Replicative fitness relates to an optimal mutant spectrum that provides the molecular basis for phenotypic flexibility, with implications for antiviral therapy. The biological impact of viral fitness renders particularly relevant the capacity of new generation sequencing to establish viral fitness landscapes. Progress with experimental model systems is becoming an important asset to understand virus behavior in the more complex environments faced during natural infections.

  18. Viral hepatitis

    DEFF Research Database (Denmark)

    Gottwein, Judith M; Bukh, Jens

    2013-01-01

    With millions of humans infected yearly with HCV, leading to cirrhosis and cancer, a vaccine is urgently needed. Cultured virus particles constitute the antigen in most antiviral vaccines. A study in mice demonstrated induction of neutralizing antibodies by immunization with cell-culture-derived ...

  19. Utilización del Método de Elisa en la detección directa de antígeno de virus diarrea viral bovina en muestras de suero sanguíneo de bovinos Use of an ELISA test in the direct diagnosis of viral antigens of Bovine Viral Diarrhea Virus (BVDV in bovine blood serum samples

    Directory of Open Access Journals (Sweden)

    G. REINHARDT

    2003-01-01

    Full Text Available El virus de la Diarrea Viral Bovina (VDVB es un agente infeccioso importante del ganado bovino y está distribuido ampliamente en el mundo, produciendo pérdidas económicas sustanciales en la producción pecuaria. La principal fuente de contagio de los animales susceptibles está en las secreciones y excreciones de los animales infectados persistentes e inmunotolerantes (PI, condición que se produce en la etapa gestacional, específicamente antes de los 120 días de preñez, período en que el sistema inmune del embrión aún no se desarrolla adecuadamente. El propósito de este estudio fue aplicar la utilización de un método inmunoenzimático (ELISA-antígeno para detectar la presencia de animales PI en planteles lecheros de la Xª Región de Chile, a partir de muestras de suero sanguíneo. Para ello se examinaron 335 sueros de bovinos provenientes de 9 predios. Los resultados obtenidos indican que el 33.3% de los planteles analizados presentaron algún animal PI y que a nivel de prevalencia intrapredial, ella varió entre 0.7 y 1.0%. Se concluyó que el método utilizado permite detectar animales PI en forma rápida y sencilla, pudiendo utilizarse en gran cantidad de muestrasBVDV is an important virus of cattle worldwide that induces to substantial economic losses in dairy farms. The major source of infection are secretions and excretions of immunotolerant and persistent infected cattle. That condition is adquired during the early gestational period. The scope of this communication is to inform the use of an ELISA test to detect BVDV persistent infected bovine using blood serum samples in cattle of 9 dairy farms from the Xth. Region of Chile. The results indicated that 0.3% of the serum samples were positive to the ELISA test, and 33.3% of the dairy herds with persistently infected animals. It is concluded that this method diagnose persistently infected cattle, and is very easy to manipulate therefore, is possible to test many animals in

  20. Distribution of viral antigen gp85 and provirus in various tissues from commercial meat-type and experimental white leghorn line 0 chickens with different subgroup J avian leukosis virus infection profiles

    Science.gov (United States)

    Immunohistochemistry (IHC) and polymerase chain reaction (PCR) were used to test for the presence of subgroup J avian leukosis virus (ALV J) envelope antigen gp85 and provirus, respectively in various tissues (adrenal gland, bone marrow, gonad, heart, kidney, liver, lung, pancreas, proventriculus, s...

  1. Recombinant viruses as vaccines against viral diseases

    Directory of Open Access Journals (Sweden)

    A.P.D. Souza

    2005-04-01

    Full Text Available Vaccine approaches to infectious diseases are widely applied and appreciated. Amongst them, vectors based on recombinant viruses have shown great promise and play an important role in the development of new vaccines. Many viruses have been investigated for their ability to express proteins from foreign pathogens and induce specific immunological responses against these antigens in vivo. Generally, gene-based vaccines can stimulate potent humoral and cellular immune responses and viral vectors might be an effective strategy for both the delivery of antigen-encoding genes and the facilitation and enhancement of antigen presentation. In order to be utilized as a vaccine carrier, the ideal viral vector should be safe and enable efficient presentation of required pathogen-specific antigens to the immune system. It should also exhibit low intrinsic immunogenicity to allow for its re-administration in order to boost relevant specific immune responses. Furthermore, the vector system must meet criteria that enable its production on a large-scale basis. Several viral vaccine vectors have thus emerged to date, all of them having relative advantages and limits depending on the proposed application, and thus far none of them have proven to be ideal vaccine carriers. In this review we describe the potential, as well as some of the foreseeable obstacles associated with viral vaccine vectors and their use in preventive medicine.

  2. Viral immunoblotting: a sensitive method for detecting viral-specific oliogoclonal bands in unconcentrated cerebrospinal fluid.

    Science.gov (United States)

    Moyle, S; Keir, G; Thompson, E J

    1984-06-01

    A new method for detecting viral antibodies in cerebrospinal fluid is described. The technique has many advantages over previously published methods in that it is highly sensitive eliminating the need to concentrate the CSF, takes 5 h to complete, avoids the use of radionucleides, and most importantly circumvents problems associated with prozone effects which occur in immunoprecipitation reaction since the viral antigen is immobilized on nitrocellulose membranes.

  3. A pathogenetic study of the early connective tissue lesions of viral caprine arthritis-encephalitis.

    OpenAIRE

    Adams, D. S.; Crawford, T B; Klevjer-Anderson, P

    1980-01-01

    Experiments were designed to correlate morphologic lesions with the presence of caprine arthritis-encephalitis virus (CAEV). Twenty-one cesarean-derived goat kids were infected with 10(6) to 10(7) TCID50 of virus, killed sequentially, and examined for viral antigens by immunofluorescence, viral infectivity by isolation and titration, and morphologic changes by light microscopy. Fluorescent viral antigens were detected from 1 to 10 days postinoculation (DPI) and only in synovial cells. Virus w...

  4. [Presence of Australia antigen in blood donors].

    Science.gov (United States)

    Gota, F

    1980-01-01

    The differential diagnosis of type A and B viral hepatitis is discussed and guidelines for the prevention of post-transfusional hospital hepatitis are proposed. Methods for the immunological demonstration of HBs antigen are illustrated, together with the respective positivity percentages in blood donors.

  5. STAINING OF VACCINIA ANTIGEN BY IMMUNOURANIUM TECHNIQUE,

    Science.gov (United States)

    An attempt to follow morphologically the development of vaccinia antigen in helium-lanthanum ( HeLa ) cells is reported. The conversion of rabbit...antisera to vaccinia virus and the preparation of vaccinia-infected HeLa cells for electron microscopy are described. With specific staining, viral

  6. Development of Antigen Capture ELISA of Detection Bovine Viral Diarrhea Virus%牛病毒性腹泻病毒抗原捕获 ELISA 方法的建立

    Institute of Scientific and Technical Information of China (English)

    范晴; 谢芝勋; 谢志勤; 刘加波; 庞耀珊; 邓显文; 谢丽基; 罗思思

    2015-01-01

    A antigen capture enzyme‐linked immunosorbent assay(ELISA) method was developed to detect antigen of bovine virus diarrhea(BVDV) using mouse monoclonal antibody against NS3 protein of bovine virus diarrhea as capture antibody and polyclonal antiserum (rabbit serum against BVDV ) as coating anti‐body .The optimum conditions were achieved :coating antibody was diluted for 1 :1600 ,the mouse mono‐clonal antibody was diluted for 1∶2 000 and the enzyme‐label antibody was diluted for 1 :2000 .BRV , IBRV and MB were detected by the Ag‐capture ELISA and the result showed that there was no crossing‐reaction with BVDV .The method has a minimum detection concentration is 7 .9 × 103 TCID50 .The result of positive detection by Ag‐capture ELISA were consistent with RT‐PCR .The result showed that the Ag‐capture ELISA was highly rapid ,specific and sensitive ,and it could be the basic for controlling BVDV .%用兔抗牛病毒性腹泻病毒(BVDV )多抗作为包被抗体,BVDV NS3单克隆抗体作为捕获抗体,建立了检测BVDV抗原的捕获ELISA 方法,对各项反应条件进行优化,最终获得最佳工作条件为兔多抗1∶1600稀释包被,NS3单抗1∶2000稀释,酶标抗体工作浓度为1∶4000稀释。特异性和敏感性试验结果表明,该方法对牛轮状病毒、牛传染性鼻气管炎病毒、牛结核杆菌无特异性交叉反应,其最低可检测7.9×103个TCID50的病毒量,与RT‐PCR方法的相比较,符合率为100%。所建立的BVDV抗原捕获ELISA 方法快速、特异、敏感可用于BVDV抗原的检测。

  7. 汉坦病毒感染BALB/c小鼠组织中特异性抗原及病毒RNA的检测%Detection of the specific antigens and viral RNA in the tissues of the BALB/c mice infected with hantavirus

    Institute of Scientific and Technical Information of China (English)

    徐永妮; 胡至察; 程林峰; 张芳琳

    2013-01-01

    Objective To establish an evaluation system about animals infected with hantavirus,an observation of the BALB/c mice infected with hantavirus was made.Methods BALB/c mice were infected with hantavirus by intramuscular injection with stock solution.The specific antigen from BALB/c mice tissues after 3 days was detected with enzyme-linked immunosorbent assay (ELISA) and viral RNA with real-time polymerase chain reaction (RT-PCR).Results Within a short term,the specific antigen and viral RNA were detected from the brain and liver at day 3 after infection,but not be detected from the heart,spleen,lung,and kidney samples.Conclusions The results provided ones with some information on animals infected with hantavirus.%目的 检测汉坦病毒感染BALB/c小鼠组织中特异性抗原及病毒RNA,建立汉坦病毒感染动物的评价体系.方法 将1000LD50的汉坦病毒悬液经肌肉注射感染BALB/c小鼠,在感染后的第3天,分别取小鼠的心、肝、脾、肺、肾、脑等组织研磨后制成病毒悬液,以ELISA法和qRT-PCR法分别检测各组织中的汉坦病毒特异性抗原及病毒RNA.结果 BALB/c小鼠感染汉坦病毒后短期内在脑和肝组织中可以检测到大量汉坦病毒特异性抗原以及病毒RNA,而心、脾、肺、肾组织中未检测到特异性抗原及病毒RNA.结论 实验结果为建立汉坦病毒感染动物模型的评价体系提供了参考依据.

  8. Problems in diagnosing viral hepatitis.

    Science.gov (United States)

    Bonino, F; Colloredo Mels, G; Bellati, G; Ideo, G; Oliveri, F; Colombatto, P; Brunetto, M R

    1993-01-01

    The most reliable method of making a specific aetiological diagnosis of chronic viral hepatitis would be to identify virus specific cytotoxic T lymphocytes responsible for the killing of virus infected hepatocytes in each patient's liver. Unfortunately, this can not be proposed for routine diagnosis and surrogate tests are required. The detection of virus markers, and even of the virus itself, does not imply that liver damage is caused by virus infection. Indirect markers of the host's antiviral immunoresponse have to be used to confirm more specifically the diagnosis of viral hepatitis. IgM antibodies against viral antigens implicated in the elimination of the virus seem to be suitable alternative candidates. Significant changes in the serum values of viraemia and aminotransferases occur within a few days, while a significant variation in liver histology takes much longer. Only the kinetics of the highly variable parameters can be used for an appropriate study of the relationship between viraemia, antiviral immunoresponse, and liver cell necrosis. Quantitative and dynamic analyses of hepatitis virus markers seem the most suitable and reliable methods of monitoring the patients eligible for antiviral treatment and identifying the most appropriate time to start this. PMID:8314490

  9. Viral Evasion of Natural Killer Cell Activation

    OpenAIRE

    Yi Ma; Xiaojuan Li; Ersheng Kuang

    2016-01-01

    Natural killer (NK) cells play a key role in antiviral innate defenses because of their abilities to kill infected cells and secrete regulatory cytokines. Additionally, NK cells exhibit adaptive memory-like antigen-specific responses, which represent a novel antiviral NK cell defense mechanism. Viruses have evolved various strategies to evade the recognition and destruction by NK cells through the downregulation of the NK cell activating receptors. Here, we review the recent findings on viral...

  10. Rapid diagnosis of viral neuroinfections by immunofluorescent and immunoperoxidase technics.

    Science.gov (United States)

    Maltseva, N; Manovich, Z; Seletskaya, T; Kaptsova, T; Nikulina, V

    1979-03-22

    The results of immunofluorescent (IF) and immunoperoxidase (IP) technics applied for the detection of antigen in cerebrospinal fluid (CSF) cells in patients with mumps, herpes zoster and herpes simplex meningitis and meningoencephalitis are presented. Thirty patients were under study. The detection of mumps and herpes zoster viral antigen in CSF cells was possible in 100% of cases investigated. Herpes simplex virus antigen was detected in four of seven cases with symptoms of severe meningoencephalitis. Complement fixation (CF) antibodies to herpes simplex virus (type I) and positive seroconversion were detected in the four latter patients. The diagnostic value of the methods used for the detection of mumps, herpes simplex and herpes zoster viral antigens in CSF cells of patients is discussed.

  11. 北京地区男男性接触人类免疫缺陷病毒感染者人类白细胞抗原-Ⅰ类分子多态性对病毒载量的影响%The influence of human leucocyte antigen-Ⅰ polymorphisms on plasma viral load in human immunodeficiency virus infected male homosexual population in Beijing

    Institute of Scientific and Technical Information of China (English)

    张欣; 王熠; 王爽; 李伟华; 胡文静; 赵丹彤; 闫惠平

    2013-01-01

    目的 分析北京地区男男性接触人群HIV感染者人类白细胞抗原(HLA)-Ⅰ的多态性及其对病毒载量的影响.方法 用序列特异性引物-聚合酶链反应(SSP-PCR)对157例慢性HIV感染者的HLA-A、HLA-B、HLA-C等位基因分型,同时检测HIV载量.正态分布的计量资料采用单因素或多因素方差分析,非正态分布的计量资料用Mann-Whitney U检验.结果 157例HIV感染者中,HLA-B携带Bw4表位簇个数与低病毒载量有关(F=3.01,P=0.045),HLA-B携带Bw4/4纯合子的感染者HIV载量为(4.19±0.76) lg IU/mL,Bw6/6纯合子的感染者为(4.63±0.74) lg IU/mL(t=2.27,P=0.010).HLA-A、HLA-B同时携带3个Bw4的感染者HIV载量为(3.92±0.97)lg IU/mL,显著低于携带1个Bw4的感染者HIV载量(4.54±0.88) lg IU/mL和不携带Bw4者HIV载量(4.60±0.72) lg IU/mL(t=2.11,P=0.039;t=2.53,P=0.015).HLA-Ⅰ类分子(HLA-A、HLA-B、HLA-C)均携带杂合子的感染者,其病毒载量与任一座位携带纯合子的感染者病毒载量比较,差异无统计学意义.HLA-Ⅰ类分子均携带杂合子且HLA-B携带Bw4/4纯合子的感染者其HIV载量中位数为4.09 lg IU/mL,低于HLA-B携带Bw6/6纯合子感染者的4.55 lg IU/mL(U=210.50,P=0.041).携带A30/B13/C06单体型或A33/B58/C03单体型的感染者其HIV载量与不携带A30/B13/C06单体型或A33/B58/C03单体型感染者比较,差异无统计学意义(t=0.40,P=0.69;t=0.68,P=0.49).结论 HIV感染者HLA-B携带Bw4/4纯合子与低病毒载量有关,且HLA Ⅰ类分子携带杂合子的个体可受HLA-B携带Bw4/4纯合子影响,这些HIV感染者病毒载量更低.%Objective To analyze the influence of the polymorphisms of human leucocyte antigen (HLA)-Ⅰ molecule and the effects on plasma viral load of human immunodeficiency virus (HIV) infected male homosexual population in Beijing.Methods The HLA-A,HLA-B,HLA-C allele were typed by sequence specific primer-polymerase chain reaction (SSP-PCR),and viral load was detected in 157 chronic HIV infected

  12. Viral Marketing Past Present Future

    OpenAIRE

    Nessipbekova, Zarina

    2010-01-01

    The work studies the viral marketing. These are past viral campaigns, viral campaigns today, and evaluates their actuality. The work tries to predict the development of viral marketing on the basis of the research done by the author.

  13. EXPERIMENTAL LIPOSOMAL VIRAL VACCINE SAFETY

    Directory of Open Access Journals (Sweden)

    Romanova OA

    2016-12-01

    Full Text Available Introduction. With the transport links development there is rather important issue respiratory viral infections spread, especially influenza. The only method controlling influenza is vaccination. Search and development effective and safe vaccines is important. Material and methods. In base SO "Mechnikov Institute Microbiology and Immunology National Ukrainian Academy Medical Sciences" in the scientific theme "Developing new approaches to creating viral vaccines and study specific activity depending of type and degree component`s modification" was created several experimental influenza vaccine with subsequent component`s modification for selecting the most optimal pattern of safety and immunogenicity. In assessing the influenza vaccine safety is using a few criteria, including, reactivity, as measured by the frequency of local and systemic adverse (negative effects, which due to its introduction, and for lipid content drugs, ability to influence oxidation processes. At present study phase was determined: a systemic reaction and local reaction of delayed-type hypersensitivity (foot pad swelling assay;b lipids and proteins peroxidation processes after administration officinal and experimental vaccines (content protein’s carbonyl groups, lipid’s hydroperoxides, activity of glutathione-peroxidase.Study objects were trivalent seasonal influenza vaccine, "Vaxigrip" (Sanofi Pasteur, S.A., France, "Inflexal V" (Biotech Ltd. Berne, Switzerland and experimental vaccine samples. Highest immunogenicity vaccines had undergone improvements and modifications using adjuvant systems and acylation influenza proteins. Liposomes 2 – the experimental influenza vaccine with a liposome negative charge and antigenic composition like split vaccines "Vaksihryp". Liposomes 2.1 - the adjuvantexperimental influenza vaccine with modifications liposomal components (etoniy and chlorophyllipt molecules embedded in liposomal membrane. Liposomes 2.2 - the adjuvant

  14. VIRAL ANTIBODIES IN PRESCHOOL CHILDREN

    Directory of Open Access Journals (Sweden)

    S. Saidi

    1974-08-01

    Full Text Available One hundred sera from children 1 - 6 years of age, representative of a large serum collection, were tested for the prevalence of antibodies against different viruses. Hemagglutination-inhibition (HI antibodies were found in 68% for measles; 61 % for rubella; 75'% for influenza A2/Hong Kong/68, 16% for influenza B/Md./59, 0% for group A arboviruses, 10% for group B arboviruses, 3% for phlebotomus fever group and 4% for Congo-Crimean hemorrhagic fever (C-CHF group of arboviruses Poliomyelitis-neutralizing antibodies for type 1, 2 and 3 were 90%; 85% and 84%~ respectively. Antibody to EH virus was detected in 84% of the sera by immuno-fluorescence. None of the sera were positive for hepatitis-B antigen or antibody by immuno-precipitation test. The prevalence of some viral antibodies found in this survey are compared with results obtained from surveys in other parts of the country.

  15. Bacterial coinfections in children with viral wheezing.

    Science.gov (United States)

    Lehtinen, P; Jartti, T; Virkki, R; Vuorinen, T; Leinonen, M; Peltola, V; Ruohola, A; Ruuskanen, O

    2006-07-01

    Bacterial coinfections occur in respiratory viral infections, but the attack rates and the clinical profile are not clear. The aim of this study was to determine bacterial coinfections in children hospitalized for acute expiratory wheezing with defined viral etiology. A total of 220 children aged 3 months to 16 years were investigated. The viral etiology of wheezing was confirmed by viral culture, antigen detection, serologic investigation, and/or PCR. Specific antibodies to common respiratory bacteria were measured from acute and convalescent serum samples. All children were examined clinically for acute otitis media, and subgroups of children were examined radiologically for sinusitis and pneumonia. Rhinovirus (32%), respiratory syncytial virus (31%), and enteroviruses (31%) were the most common causative viruses. Serologic evidence of bacterial coinfection was found in 18% of the children. Streptococcus pneumoniae (8%) and Mycoplasma pneumoniae (5%) were the most common causative bacteria. Acute otitis media was diagnosed in 44% of the children. Chest radiographs showed alveolar infiltrates in 10%, and paranasal radiographs and clinical signs showed sinusitis in 17% of the older children studied. Leukocyte counts and serum C-reactive protein levels were low in a great majority of patients. Viral lower respiratory tract infection in children is often associated with bacterial-type upper respiratory tract infections. However, coexisting bacterial lower respiratory tract infections that induce systemic inflammatory response are seldom detected.

  16. Positive Correlation between Epstein-Barr Virus Viral Load and Anti-Viral Capsid Immunoglobulin G Titers Determined for Hodgkin's Lymphoma Patients and Their Relatives

    OpenAIRE

    Besson, Caroline; Amiel, Corinne; Le-Pendeven, Catherine; Brice, Pauline; Fermé, Christophe; Carde, Patrice; Hermine, Olivier; Raphael, Martine; Abel, Laurent; Nicolas, Jean-Claude

    2006-01-01

    Markers of Epstein-Barr virus (EBV) infection include measures of specific serological titers and of viral load (VLo) in peripheral blood mononuclear cells. Few studies have investigated the correlation between these two phenotypes. Here, we found that there was no correlation between VLo and either anti-EBV nuclear antigen type 1 or anti-early antigen immunoglobulin G (IgG) titer but that anti-viral capsid antigen (VCA) IgG titer increased with VLo in peripheral blood mononuclear cells in pa...

  17. RNAi, a new therapeutic strategy against viral infection

    Institute of Scientific and Technical Information of China (English)

    Fischer L. TAN; James Q. YIN

    2004-01-01

    RNA interference (RNAi) is an adaptive defense mechanism triggered by double-stranded RNA (dsRNA). It is a powerful reverse genetic tool that has been widely employed to silence gene expression in mammalian and human cells.RNAi-based gene therapies, especially in viral diseases have become more and more interesting and promising. Recently,small interfering RNA (siRNA) can be used to protect host from viral infection, inhibit the expression of viral antigen and accessory genes, control the transcription and replication of viral genome, hinder the assembly of viral particles, and display influences in virus-host interactions. In this review, we attempt to present recent progresses of this breakthrough technology in the above fields and summarize the possibilities of siRNA-based drugs.

  18. Kinetics of antibody-induced modulation of respiratory syncytial virus antigens in a human epithelial cell line

    Directory of Open Access Journals (Sweden)

    Gómez-Garcia Beatriz

    2007-07-01

    Full Text Available Abstract Background The binding of viral-specific antibodies to cell-surface antigens usually results in down modulation of the antigen through redistribution of antigens into patches that subsequently may be internalized by endocytosis or may form caps that can be expelled to the extracellular space. Here, by use of confocal-laser-scanning microscopy we investigated the kinetics of the modulation of respiratory syncytial virus (RSV antigen by RSV-specific IgG. RSV-infected human epithelial cells (HEp-2 were incubated with anti-RSV polyclonal IgG and, at various incubation times, the RSV-cell-surface-antigen-antibody complexes (RSV Ag-Abs and intracellular viral proteins were detected by indirect immunoflourescence. Results Interaction of anti-RSV polyclonal IgG with RSV HEp-2 infected cells induced relocalization and aggregation of viral glycoproteins in the plasma membrane formed patches that subsequently produced caps or were internalized through clathrin-mediated endocytosis participation. Moreover, the concentration of cell surface RSV Ag-Abs and intracellular viral proteins showed a time dependent cyclic variation and that anti-RSV IgG protected HEp-2 cells from viral-induced death. Conclusion The results from this study indicate that interaction between RSV cell surface proteins and specific viral antibodies alter the expression of viral antigens expressed on the cells surface and intracellular viral proteins; furthermore, interfere with viral induced destruction of the cell.

  19. Vaccines for viral and parasitic diseases produced with baculovirus vectors

    NARCIS (Netherlands)

    Oers, van M.M.

    2006-01-01

    The baculovirus¿insect cell expression system is an approved system for the production of viral antigens with vaccine potential for humans and animals and has been used for production of subunit vaccines against parasitic diseases as well. Many candidate subunit vaccines have been expressed in this

  20. Sharing the burden: antigen transport and firebreaks in immune responses.

    Science.gov (United States)

    Handel, Andreas; Yates, Andrew; Pilyugin, Sergei S; Antia, Rustom

    2009-05-06

    Communication between cells is crucial for immune responses. An important means of communication during viral infections is the presentation of viral antigen on the surface of an infected cell. Recently, it has been shown that antigen can be shared between infected and uninfected cells through gap junctions, connexin-based channels, that allow the transport of small molecules. The uninfected cell receiving antigen can present it on its surface. Cells presenting viral antigen are detected and killed by cytotoxic T lymphocytes. The killing of uninfected cells can lead to increased immunopathology. However, the immune response might also profit from killing those uninfected bystander cells. One benefit might be the removal of future 'virus factories'. Another benefit might be through the creation of 'firebreaks', areas void of target cells, which increase the diffusion time of free virions, making their clearance more likely. Here, we use theoretical models and simulations to explore how the mechanism of gap junction-mediated antigen transport (GMAT) affects the dynamics of the virus and immune response. We show that under the assumption of a well-mixed system, GMAT leads to increased immunopathology, which always outweighs the benefit of reduced virus production due to the removal of future virus factories. By contrast, a spatially explicit model leads to quite different results. Here we find that the firebreak mechanism reduces both viral load and immunopathology. Our study thus shows the potential benefits of GMAT and illustrates how spatial effects may be crucial for the quantitative understanding of infection dynamics and immune responses.

  1. Fibroblasts as Efficient Antigen-Presenting Cells in Lymphoid Organs

    Science.gov (United States)

    Kundig, Thomas M.; Bachmann, Martin F.; Dipaolo, Claudio; Simard, John J. L.; Battegay, Manuel; Lother, Heinz; Gessner, Andre; Kuhlcke, Klaus; Ohashi, Pamela S.; Hengartner, Hans; Zinkernagel, Rolf M.

    1995-06-01

    Only so-called "professional" antigen-presenting cells (APCs) of hematopoietic origin are believed capable of inducing T lymphocyte responses. However, fibroblasts transfected with viral proteins directly induced antiviral cytotoxic T lymphocyte responses in vivo, without involvement of host APCs. Fibroblasts induced T cells only in the milieu of lymphoid organs. Thus, antigen localization affects self-nonself discrimination and cell-based vaccine strategies.

  2. Polymer nanomicelles for efficient mucus delivery and antigen-specific high mucosal immunity.

    Science.gov (United States)

    Noh, Young-Woock; Hong, Ji Hyun; Shim, Sang-Mu; Park, Hye Sun; Bae, Hee Ho; Ryu, Eun Kyoung; Hwang, Jung Hwan; Lee, Chul-Ho; Cho, Seong Hun; Sung, Moon-Hee; Poo, Haryoung; Lim, Yong Taik

    2013-07-22

    Micelles for mucosal immunity: A mucosal vaccine system based on γ-PGA nanomicelles and viral antigens was synthesized. The intranasal administration of the vaccine system induces a high immune response both in the humoral and cellular immunity (see picture).

  3. [Emergent viral infections

    NARCIS (Netherlands)

    Galama, J.M.D.

    2001-01-01

    The emergence and re-emergence of viral infections is an ongoing process. Large-scale vaccination programmes led to the eradication or control of some viral infections in the last century, but new viruses are always emerging. Increased travel is leading to a rise in the importation of exotic infecti

  4. Viral Haemorrhagic Septicaemia Virus

    DEFF Research Database (Denmark)

    Olesen, Niels Jørgen; Skall, Helle Frank

    2013-01-01

    This chapter covers the genetics (genotypes and serotypes), clinical signs, host species, transmission, prevalence, diagnosis, control and prevention of viral haemorrhagic septicaemia virus.......This chapter covers the genetics (genotypes and serotypes), clinical signs, host species, transmission, prevalence, diagnosis, control and prevention of viral haemorrhagic septicaemia virus....

  5. Kinetics of antigen expression and epitope presentation during virus infection.

    Directory of Open Access Journals (Sweden)

    Nathan P Croft

    2013-01-01

    Full Text Available 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.

  6. Tonsillar crypt epithelium is an important extra-central nervous system site for viral replication in EV71 encephalomyelitis.

    Science.gov (United States)

    He, Yaoxin; Ong, Kien Chai; Gao, Zifen; Zhao, Xishun; Anderson, Virginia M; McNutt, Michael A; Wong, Kum Thong; Lu, Min

    2014-03-01

    Enterovirus 71 (EV71; family Picornaviridae, species human Enterovirus A) usually causes hand, foot, and mouth disease, which may rarely be complicated by fatal encephalomyelitis. We investigated extra-central nervous system (extra-CNS) tissues capable of supporting EV71 infection and replication, and have correlated tissue infection with expression of putative viral entry receptors, scavenger receptor B2 (SCARB2), and P-selectin glycoprotein ligand-1 (PSGL-1). Formalin-fixed, paraffin-embedded CNS and extra-CNS tissues from seven autopsy cases were examined by IHC and in situ hybridization to evaluate viral antigens and RNA. Viral receptors were identified with IHC. In all seven cases, the CNS showed stereotypical distribution of inflammation and neuronal localization of viral antigens and RNA, confirming the clinical diagnosis of EV71 encephalomyelitis. In six cases in which tonsillar tissues were available, viral antigens and/or RNA were localized to squamous epithelium lining the tonsillar crypts. Tissues from the gastrointestinal tract, pancreas, mesenteric nodes, spleen, and skin were all negative for viral antigens/RNA. Our novel findings strongly suggest that tonsillar crypt squamous epithelium supports active viral replication and represents an important source of viral shedding that facilitates person-to-person transmission by both the fecal-oral or oral-oral routes. It may also be a portal for viral entry. A correlation between viral infection and SCARB2 expression appears to be more significant than for PSGL-1 expression.

  7. Protamine-based nanoparticles as new antigen delivery systems.

    Science.gov (United States)

    González-Aramundiz, José Vicente; Peleteiro Olmedo, Mercedes; González-Fernández, África; Alonso Fernández, María José; Csaba, Noemi Stefánia

    2015-11-01

    The use of biodegradable nanoparticles as antigen delivery vehicles is an attractive approach to overcome the problems associated with the use of Alum-based classical adjuvants. Herein we report, the design and development of protamine-based nanoparticles as novel antigen delivery systems, using recombinant hepatitis B surface antigen as a model viral antigen. The nanoparticles, composed of protamine and a polysaccharide (hyaluronic acid or alginate), were obtained using a mild ionic cross-linking technique. The size and surface charge of the nanoparticles could be modulated by adjusting the ratio of the components. Prototypes with optimal physicochemical characteristics and satisfactory colloidal stability were selected for the assessment of their antigen loading capacity, antigen stability during storage and in vitro and in vivo proof-of-concept studies. In vitro studies showed that antigen-loaded nanoparticles induced the secretion of cytokines by macrophages more efficiently than the antigen in solution, thus indicating a potential adjuvant effect of the nanoparticles. Finally, in vivo studies showed the capacity of these systems to trigger efficient immune responses against the hepatitis B antigen following intramuscular administration, suggesting the potential interest of protamine-polysaccharide nanoparticles as antigen delivery systems.

  8. Viral marketing on the Internet

    OpenAIRE

    Štverák, Martin

    2008-01-01

    Thesis provides an overview of viral marketing. It describes the process by which you can be inspired to implement viral campaign. The thesis includes analysis of specific viral Web project. The aim of this thesis is to create a breakdown of the various components of viral marketing, to establish conditions that should be satisfied for the viral marketing to success, suggesting how to use viral marketing on social network Facebook and evaluate the various components of this service for the pr...

  9. Heterologous Protection Against Influenza by Injection of DNA Encoding a Viral Protein

    Science.gov (United States)

    Ulmer, Jeffrey B.; Donnelly, John J.; Parker, Suezanne E.; Rhodes, Gary H.; Felgner, Philip L.; Dwarki, V. J.; Gromkowski, Stanislaw H.; Deck, R. Randall; Dewitt, Corrille M.; Friedman, Arthur; Hawe, Linda A.; Leander, Karen R.; Martinez, Douglas; Perry, Helen C.; Shiver, John W.; Montgomery, Donna L.; Liu, Margaret A.

    1993-03-01

    Cytotoxic T lymphocytes (CTLs) specific for conserved viral antigens can respond to different strains of virus, in contrast to antibodies, which are generally strain-specific. The generation of such CTLs in vivo usually requires endogenous expression of the antigen, as occurs in the case of virus infection. To generate a viral antigen for presentation to the immune system without the limitations of direct peptide delivery or viral vectors, plasmid DNA encoding influenza A nucleoprotein was injected into the quadriceps of BALB/c mice. This resulted in the generation of nucleoprotein-specific CTLs and protection from a subsequent challenge with a heterologous strain of influenza A virus, as measured by decreased viral lung titers, inhibition of mass loss, and increased survival.

  10. Viral Gastroenteritis (Stomach Flu)

    Science.gov (United States)

    ... There's often no specific medical treatment for viral gastroenteritis. Antibiotics aren't effective against viruses, and overusing them can contribute to the development of antibiotic-resistant strains of bacteria. Treatment initially consists of self-care measures. To ...

  11. Viral quasispecies complexity measures.

    Science.gov (United States)

    Gregori, Josep; Perales, Celia; Rodriguez-Frias, Francisco; Esteban, Juan I; Quer, Josep; Domingo, Esteban

    2016-06-01

    Mutant spectrum dynamics (changes in the related mutants that compose viral populations) has a decisive impact on virus behavior. The several platforms of next generation sequencing (NGS) to study viral quasispecies offer a magnifying glass to study viral quasispecies complexity. Several parameters are available to quantify the complexity of mutant spectra, but they have limitations. Here we critically evaluate the information provided by several population diversity indices, and we propose the introduction of some new ones used in ecology. In particular we make a distinction between incidence, abundance and function measures of viral quasispecies composition. We suggest a multidimensional approach (complementary information contributed by adequately chosen indices), propose some guidelines, and illustrate the use of indices with a simple example. We apply the indices to three clinical samples of hepatitis C virus that display different population heterogeneity. Areas of virus biology in which population complexity plays a role are discussed.

  12. NCBI viral genomes resource.

    Science.gov (United States)

    Brister, J Rodney; Ako-Adjei, Danso; Bao, Yiming; Blinkova, Olga

    2015-01-01

    Recent technological innovations have ignited an explosion in virus genome sequencing that promises to fundamentally alter our understanding of viral biology and profoundly impact public health policy. Yet, any potential benefits from the billowing cloud of next generation sequence data hinge upon well implemented reference resources that facilitate the identification of sequences, aid in the assembly of sequence reads and provide reference annotation sources. The NCBI Viral Genomes Resource is a reference resource designed to bring order to this sequence shockwave and improve usability of viral sequence data. The resource can be accessed at http://www.ncbi.nlm.nih.gov/genome/viruses/ and catalogs all publicly available virus genome sequences and curates reference genome sequences. As the number of genome sequences has grown, so too have the difficulties in annotating and maintaining reference sequences. The rapid expansion of the viral sequence universe has forced a recalibration of the data model to better provide extant sequence representation and enhanced reference sequence products to serve the needs of the various viral communities. This, in turn, has placed increased emphasis on leveraging the knowledge of individual scientific communities to identify important viral sequences and develop well annotated reference virus genome sets.

  13. Immigration and viral hepatitis.

    Science.gov (United States)

    Sharma, Suraj; Carballo, Manuel; Feld, Jordan J; Janssen, Harry L A

    2015-08-01

    WHO estimates reveal that the global prevalence of viral hepatitis may be as high as 500 million, with an annual mortality rate of up to 1.3 million individuals. The majority of this global burden of disease is borne by nations of the developing world with high rates of vertical and iatrogenic transmission of HBV and HCV, as well as poor access to healthcare. In 2013, 3.2% of the global population (231 million individuals) migrated into a new host nation. Migrants predominantly originate from the developing countries of the south, into the developed economies of North America and Western Europe. This mass migration of individuals from areas of high-prevalence of viral hepatitis poses a unique challenge to the healthcare systems of the host nations. Due to a lack of universal standards for screening, vaccination and treatment of viral hepatitis, the burden of chronic liver disease and hepatocellular carcinoma continues to increase among migrant populations globally. Efforts to increase case identification and treatment among migrants have largely been limited to small outreach programs in urban centers, such that the majority of migrants with viral hepatitis continue to remain unaware of their infection. This review summarizes the data on prevalence of viral hepatitis and burden of chronic liver disease among migrants, current standards for screening and treatment of immigrants and refugees, and efforts to improve the identification and treatment of viral hepatitis among migrants.

  14. Bayesian nonparametric clustering in phylogenetics: modeling antigenic evolution in influenza.

    Science.gov (United States)

    Cybis, Gabriela B; Sinsheimer, Janet S; Bedford, Trevor; Rambaut, Andrew; Lemey, Philippe; Suchard, Marc A

    2017-01-18

    Influenza is responsible for up to 500,000 deaths every year, and antigenic variability represents much of its epidemiological burden. To visualize antigenic differences across many viral strains, antigenic cartography methods use multidimensional scaling on binding assay data to map influenza antigenicity onto a low-dimensional space. Analysis of such assay data ideally leads to natural clustering of influenza strains of similar antigenicity that correlate with sequence evolution. To understand the dynamics of these antigenic groups, we present a framework that jointly models genetic and antigenic evolution by combining multidimensional scaling of binding assay data, Bayesian phylogenetic machinery and nonparametric clustering methods. We propose a phylogenetic Chinese restaurant process that extends the current process to incorporate the phylogenetic dependency structure between strains in the modeling of antigenic clusters. With this method, we are able to use the genetic information to better understand the evolution of antigenicity throughout epidemics, as shown in applications of this model to H1N1 influenza. Copyright © 2017 John Wiley & Sons, Ltd.

  15. Bile acids for viral hepatitis

    DEFF Research Database (Denmark)

    Chen, Weikeng; Liu, J; Gluud, C

    2003-01-01

    The viral hepatitides are common causes of liver diseases globally. Trials have assessed bile acids for patients with viral hepatitis, but no consensus was reached regarding their usefulness.......The viral hepatitides are common causes of liver diseases globally. Trials have assessed bile acids for patients with viral hepatitis, but no consensus was reached regarding their usefulness....

  16. Latent viral immune inflammatory response model for chronic multisymptom illness.

    Science.gov (United States)

    Maloney, Sean R; Jensen, Susan; Gil-Rivas, Virginia; Goolkasian, Paula

    2013-03-01

    A latent viral immune inflammatory response (LVIIR) model is presented which integrates factors that contribute to chronic multisymptom illness (CMI) in both the veteran and civilian populations. The LVIIR model for CMI results from an integration of clinical experience with a review of the literature in four distinct areas: (1) studies of idiopathic multisymptom illness in the veteran population including two decades of research on Gulf War I veterans with CMI, (2) new evidence supporting the existence of chronic inflammatory responses to latent viral antigens and the effect these responses may have on the nervous system, (3) recent discoveries concerning the role of vitamin D in maintaining normal innate and adaptive immunity including suppression of latent viruses and regulation of the immune inflammatory response, and (4) the detrimental effects of extreme chronic repetitive stress (ECRS) on the immune and nervous systems. The LVIIR model describes the pathophysiology of a pathway to CMI and presents a new direction for the clinical assessment of CMI that includes the use of neurological signs from a physical exam, objective laboratory data, and a new proposed latent viral antigen-antibody imaging technique for the peripheral and central nervous system. The LVIIR model predicts that CMI can be treated by a focus on reversal of immune system impairment, suppression of latent viruses and their antigens, and healing of nervous system tissue damaged by chronic inflammation associated with latent viral antigens and by ECRS. In addition, the LVIIR model suggests that maintaining optimal serum 25 OH vitamin D levels will maximize immune system suppression of latent viruses and their antigens and will minimize immune system inflammation. This model also emphasizes the importance of decreasing ECRS to improve immune system function and to minimize nervous system injury from excess serum glucocorticoid levels. The proposed model supports growing evidence that increasing

  17. HBeAg and not genotypes predicts viral load in patients with hepatitis B in Denmark: a nationwide cohort study

    DEFF Research Database (Denmark)

    Krarup, Henrik Bygum; Andersen, Stig; Madsen, Poul Henning;

    2011-01-01

    To explore the influence of HBV genotype on viral load in patients with HBV infection, and to investigate the relation to gender, age and country of origin or antibodies against hepatitis Be antigen (anti-HBe).......To explore the influence of HBV genotype on viral load in patients with HBV infection, and to investigate the relation to gender, age and country of origin or antibodies against hepatitis Be antigen (anti-HBe)....

  18. HBeAg and not genotypes predicts viral load in patients with hepatitis B in Denmark: A nationwide cohort study

    DEFF Research Database (Denmark)

    Krarup, Henrik; Andersen, Stig; Madsen, Poul Henning;

    2011-01-01

    To explore the influence of HBV genotype on viral load in patients with HBV infection, and to investigate the relation to gender, age and country of origin or antibodies against hepatitis Be antigen (anti-HBe).......To explore the influence of HBV genotype on viral load in patients with HBV infection, and to investigate the relation to gender, age and country of origin or antibodies against hepatitis Be antigen (anti-HBe)....

  19. PREVALENCE OF BOVINE VIRAL DIARRHOEA VIRUS IN WEST BENGAL, INDIA

    Directory of Open Access Journals (Sweden)

    Reshmi Ghosh

    2015-12-01

    Full Text Available Bovine Viral Diarrhea (BVD is one of the most economically important diseases in cattle. The present study was undertaken to diagnose the persistently infected (PI animals by AntigenELISA and Reverse Transcriptase PCR using serum samples from organized farms as well as rural areas of West Bengal. The results showed that out of 964 serum samples tested 07 (0.73% was positive for BVDV by Antigen-ELISA. For further confirmation, RNA was extracted from the positive samples and RT-PCR was performed with 5' UTR specific primers which showed 294 bp amplicons. This finding showed circulation of BVDV in cattle in West Bengal, India.

  20. Viral infections in pigeons.

    Science.gov (United States)

    Marlier, D; Vindevogel, H

    2006-07-01

    This review provides a current update on the major viral diseases of the domestic pigeon (Columba livia domestica), based on scientific reports and clinical experience. Paramyxovirus 1, adenovirus, rotavirus, herpesvirus 1, poxvirus and circovirus infections are described according to common clinical signs and target tissues. Since pigeons are sometimes treated as if they were poultry, the review also summarises the common viral infections of poultry for which pigeons are considered resistant. It is hoped that the review will provide a useful reference for veterinarians and others and offer advice on the diagnosis, treatment and prevention of the major infectious diseases of pigeons.

  1. Viral meningitis and encephalitis.

    Science.gov (United States)

    Tuppeny, Misti

    2013-09-01

    Meningitis is an inflammation of the meninges, whereas encephalitis is inflammation of the parenchymal brain tissue. The single distinguishing element between the 2 diagnoses is the altered state of consciousness, focal deficits, and seizures found in encephalitis. Consequently meningoencephalitis is a term used when both findings are present in the patient. Viral meningitis is not necessarily reported as it is often underdiagnosed, whereas encephalitis cases are on the increase in various areas of North America. Improved imaging and viral diagnostics, as well as enhanced neurocritical care management, have improved patient outcomes to date.

  2. Benefit of Hepatitis C Virus Core Antigen Assay in Prediction of Therapeutic Response to Interferon and Ribavirin Combination Therapy

    OpenAIRE

    Takahashi, Masahiko; Saito, Hidetsugu; Higashimoto, Makiko; Atsukawa, Kazuhiro; Ishii, Hiromasa

    2005-01-01

    A highly sensitive second-generation hepatitis C virus (HCV) core antigen assay has recently been developed. We compared viral disappearance and first-phase kinetics between commercially available core antigen (Ag) assays, Lumipulse Ortho HCV Ag (Lumipulse-Ag), and a quantitative HCV RNA PCR assay, Cobas Amplicor HCV Monitor test, version 2 (Amplicor M), to estimate the predictive benefit of a sustained viral response (SVR) and non-SVR in 44 genotype 1b patients treated with interferon (IFN) ...

  3. Eosinofil Sel Penyaji Antigen

    Directory of Open Access Journals (Sweden)

    Safari Wahyu Jatmiko

    2015-04-01

    Full Text Available Sel eosinofil merupakan jenis sel lekosit yang terlibat dalam berbagai patogenesis penyakit. Sel eosinofil pada awalnya dikenal sebagai sel efektor  dari sistem imunitas alamiah. Akan tetapi, kemampuan sel eosinofil dalam memfagositosis patogen menimbulkan dugaan bahwa sel eosinofil ikut berperan sebagai sel penyaji antigen. Hal ini dianalogikan dengan sel makrofag dan sel dendritik yang bisa memfagositosis dan menyajikan antigen sebagai hasil dari degradasi patogen yang difagositosis. Untuk menjawab permasalahan ini, penulis melakukan penelusuran artikel tentang eosinofil sebagai sel penyaji antigen melalui US National Library of Medicine National Institute of Healthdengan kata kunci eoshinophil dan antigen presenting cell. Hasil penelusuran adalah ditemukannya 10 artikel yang relevan dengan topik. Hasil dari sintesis kesepuluh jurnal tersebut adalah sel eosinofil mampu berperan sebagai sel penyaji antigen yang profesional (professionalantigenpresentng cell

  4. Interleukin-10 determines viral clearance or persistence in vivo

    Science.gov (United States)

    Brooks, David G; Trifilo, Matthew J.; Edelmann, Kurt H.; Teyton, Luc; McGavern, Dorian B; Oldstone, Michael B A

    2008-01-01

    Persistent viral infections are a major health concern. One obstacle inhibiting the clearance of persistent infections is functional inactivation of antiviral T cells. Although such immunosuppression occurs rapidly after infection, the mechanisms that induce the loss of T-cell activity and promote viral persistence are unknown. Herein we document that persistent viral infection in mice results in a significant upregulation of interleukin (IL)-10 by antigen-presenting cells, leading to impaired T-cell responses. Genetic removal of Il10 resulted in the maintenance of robust effector T-cell responses, the rapid elimination of virus and the development of antiviral memory T-cell responses. Therapeutic administration of an antibody that blocks the IL-10 receptor restored T-cell function and eliminated viral infection. Thus, we identify a single molecule that directly induces immunosuppression leading to viral persistence and demonstrate that a therapy to neutralize IL-10 results in T-cell recovery and the prevention of viral persistence. PMID:17041596

  5. Bile acids for viral hepatitis

    DEFF Research Database (Denmark)

    Chen, Weikeng; Liu, J; Gluud, C

    2007-01-01

    Trials have assessed bile acids for patients with viral hepatitis, but no consensus has been reached regarding their usefulness.......Trials have assessed bile acids for patients with viral hepatitis, but no consensus has been reached regarding their usefulness....

  6. Viral Marketing and Academic Institution

    OpenAIRE

    Koktová, Silvie

    2010-01-01

    This bachelor thesis examines modern and constantly developing kind of internet marketing -- the so called viral marketing. It deals with its origin, principle, process, advantages and disadvantages, types of viral marketing and presumptions of creating successful viral campaign. The aim of the theoretical part is especially the understanding of viral marketing as one of the effective instruments of contemporary marketing. In this theoretical part the thesis also elaborates a marketing school...

  7. Measles viral load may reflect SSPE disease progression

    Directory of Open Access Journals (Sweden)

    Jin L

    2006-06-01

    Full Text Available Abstract Subacute sclerosing panencephalitis (SSPE is a rare, slowly progressive neurological disorder caused by the persistent infection with measles virus (MV. Despite much research into SSPE, its pathology remains obscure. We examined autopsy tissues of eight SSPE patients by real time quantitative PCR, immunohistochemistry and immunoblotting to determine viral load. MV N, M and H gene RNA could be detected in the central nervous system (CNS of all patients and in two non-CNS tissues of one patient. The viral burden between patients differed up to four-fold by quantitative PCR and corresponded with detection of MV protein. The level of both viral RNA and antigen in the brain may correlate with disease progression.

  8. Viral quasispecies evolution

    OpenAIRE

    Domingo, Esteban; Sheldon, Julie; Perales, Celia

    2012-01-01

    Summary: Evolution of RNA viruses occurs through disequilibria of collections of closely related mutant spectra or mutant clouds termed viral quasispecies. Here we review the origin of the quasispecies concept and some biological implications of quasispecies dynamics. Two main aspects are addressed: (i) mutant clouds as reservoirs of phenotypic variants for virus adaptability and (ii) the internal interactions that are established within mutant spectra that render a virus ensemble the unit of...

  9. Viral membrane fusion

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, Stephen C., E-mail: harrison@crystal.harvard.edu

    2015-05-15

    Membrane fusion is an essential step when enveloped viruses enter cells. Lipid bilayer fusion requires catalysis to overcome a high kinetic barrier; viral fusion proteins are the agents that fulfill this catalytic function. Despite a variety of molecular architectures, these proteins facilitate fusion by essentially the same generic mechanism. Stimulated by a signal associated with arrival at the cell to be infected (e.g., receptor or co-receptor binding, proton binding in an endosome), they undergo a series of conformational changes. A hydrophobic segment (a “fusion loop” or “fusion peptide”) engages the target-cell membrane and collapse of the bridging intermediate thus formed draws the two membranes (virus and cell) together. We know of three structural classes for viral fusion proteins. Structures for both pre- and postfusion conformations of illustrate the beginning and end points of a process that can be probed by single-virion measurements of fusion kinetics. - Highlights: • Viral fusion proteins overcome the high energy barrier to lipid bilayer merger. • Different molecular structures but the same catalytic mechanism. • Review describes properties of three known fusion-protein structural classes. • Single-virion fusion experiments elucidate mechanism.

  10. Deteccion de citomegalovirus mediante la tecnica de inmunoperoxidasa y aislamiento viral Cytomegalovirus detection by Immunoperoxidase assay and viral isolation

    Directory of Open Access Journals (Sweden)

    Maritza Alvarez

    1991-06-01

    Full Text Available En el presente estudio se comparó la técnica de inmunoperoxidasa para la detección de citomegalovirus (IPCMV utilizando anticuerpos monoclonales que reconocen proteínas precoces virales con el método convencional de aislamiento viral en fibroblastos humanos. Un total de 150 muestras de orina fueron examinadas encontrando una sensibilidad de un 89.8% y una especificidad de 91.3% de la técnica de IPCMV comparada con el aislamiento viral. Una de las ventajas que presentó la IPCMV fue la rapidez con que fueron obtenidos los resultados (48 horas mientras que el aislamiento viral fue como promedio 14 días.An Immunoperoxidase assay was applied to detect early antigens of Cytomegalovirus (CMV in 150 urine samples from immunocompromised patients, using the commercial available monoclonal antibody against CMV El3. The detection of early antigen by IP (IPCMV is compared to the conventional cell culture isolation regarding specificity and sensitivity in order to evaluate is usefulness in the diagnostic of CMV infections. The IPCMV showed a sensitivity of 89.8% and a specificity of 91.3% when compared to the isolation method. The great advantage of the IPCMV is based on the shorter time results are achieved, since 48-72 Hs can be enough to provide evidence of CMV infection, while in the isolation technique cytopatho-genic effect was present around 14 days after sample inoculation.

  11. HTLV-1 Rex Tunes the Cellular Environment Favorable for Viral Replication

    Directory of Open Access Journals (Sweden)

    Kazumi Nakano

    2016-02-01

    Full Text Available Human T-cell leukemia virus type-1 (HTLV-1 Rex is a viral RNA binding protein. The most important and well-known function of Rex is stabilizing and exporting viral mRNAs from the nucleus, particularly for unspliced/partially-spliced mRNAs encoding the structural proteins essential for viral replication. Without Rex, these unspliced viral mRNAs would otherwise be completely spliced. Therefore, Rex is vital for the translation of structural proteins and the stabilization of viral genomic RNA and, thus, for viral replication. Rex schedules the period of extensive viral replication and suppression to enter latency. Although the importance of Rex in the viral life-cycle is well understood, the underlying molecular mechanism of how Rex achieves its function has not been clarified. For example, how does Rex protect unspliced/partially-spliced viral mRNAs from the host cellular splicing machinery? How does Rex protect viral mRNAs, antigenic to eukaryotic cells, from cellular mRNA surveillance mechanisms? Here we will discuss these mechanisms, which explain the function of Rex as an organizer of HTLV-1 expression based on previously and recently discovered aspects of Rex. We also focus on the potential influence of Rex on the homeostasis of the infected cell and how it can exert its function.

  12. HTLV-1 Rex Tunes the Cellular Environment Favorable for Viral Replication.

    Science.gov (United States)

    Nakano, Kazumi; Watanabe, Toshiki

    2016-02-24

    Human T-cell leukemia virus type-1 (HTLV-1) Rex is a viral RNA binding protein. The most important and well-known function of Rex is stabilizing and exporting viral mRNAs from the nucleus, particularly for unspliced/partially-spliced mRNAs encoding the structural proteins essential for viral replication. Without Rex, these unspliced viral mRNAs would otherwise be completely spliced. Therefore, Rex is vital for the translation of structural proteins and the stabilization of viral genomic RNA and, thus, for viral replication. Rex schedules the period of extensive viral replication and suppression to enter latency. Although the importance of Rex in the viral life-cycle is well understood, the underlying molecular mechanism of how Rex achieves its function has not been clarified. For example, how does Rex protect unspliced/partially-spliced viral mRNAs from the host cellular splicing machinery? How does Rex protect viral mRNAs, antigenic to eukaryotic cells, from cellular mRNA surveillance mechanisms? Here we will discuss these mechanisms, which explain the function of Rex as an organizer of HTLV-1 expression based on previously and recently discovered aspects of Rex. We also focus on the potential influence of Rex on the homeostasis of the infected cell and how it can exert its function.

  13. Tracking the Antigenic Evolution of Foot-and-Mouth Disease Virus.

    Directory of Open Access Journals (Sweden)

    Richard Reeve

    Full Text Available Quantifying and predicting the antigenic characteristics of a virus is something of a holy grail for infectious disease research because of its central importance to the emergence of new strains, the severity of outbreaks, and vaccine selection. However, these characteristics are defined by a complex interplay of viral and host factors so that phylogenetic measures of viral similarity are often poorly correlated to antigenic relationships. Here, we generate antigenic phylogenies that track the phenotypic evolution of two serotypes of foot-and-mouth disease virus by combining host serology and viral sequence data to identify sites that are critical to their antigenic evolution. For serotype SAT1, we validate our antigenic phylogeny against monoclonal antibody escape mutants, which match all of the predicted antigenic sites. For serotype O, we validate it against known sites where available, and otherwise directly evaluate the impact on antigenic phenotype of substitutions in predicted sites using reverse genetics and serology. We also highlight a critical and poorly understood problem for vaccine selection by revealing qualitative differences between assays that are often used interchangeably to determine antigenic match between field viruses and vaccine strains. Our approach provides a tool to identify naturally occurring antigenic substitutions, allowing us to track the genetic diversification and associated antigenic evolution of the virus. Despite the hugely important role vaccines have played in enhancing human and animal health, vaccinology remains a conspicuously empirical science. This study advances the field by providing guidance for tuning vaccine strains via site-directed mutagenesis through this high-resolution tracking of antigenic evolution of the virus between rare major shifts in phenotype.

  14. 聚乙二醇干扰素α-2a联合阿德福韦治疗e抗原阳性高病毒载量慢性乙型肝炎给药时机的选择%Appropriate Time Selection for Pegylated Interferonα-2a Combined with Adefovir in Treatment of Chronic Hep-atitis B Patients with High Viral Load of Positive e Antigens

    Institute of Scientific and Technical Information of China (English)

    安红杰; 何文艳; 徐金凤; 赵崇山; 高美丽

    2015-01-01

    Objective To investigate the appropriate time selection of Pegylated interferonα-2a (peg-IFNα-2a) combined with Adefovir ( ADV) in treatment of chronic hepatitis B patients with high viral load of positive e antigens. Methods A total of 90 chronic hepatitis B patients with positive e antigens ( HBeAg ) ( HBV-DNA≥7 log10 U/ml ) were divided into group A (n=30), group B (n=30) and group C (n=30). Group A underwent peg-IFNα-2a com-bined with ADV at the beginning;group B underwent ADV at the beginning, and then ADV combined with peg-IFNα-2a was given when HBV-DNA was inhibited to 4-5 log10 U/ml;group C underwent ADV at the beginning, and then ADV combined with peg-IFNα-2a was given when HBV-DNA was inhibited to 3-4 log10 U/ml. The courses of combined thera-pies in the three groups were not less than 48 weeks. The differences in seroconversion rates of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg), HBV-DNA negative conversion rate and alanine transarninase (ALT) normalization rate were comparatively analyzed, and the incidence rates of adverse reactions were also observed among the three groups in the 24th and 48th week of combined therapy. Results In the 24th week of combined therapy, the differ-ences in HBsAg seroconversion rate, ALT normalization rate and HBV-DNA negative conversion rate in the three groups were not statistically significant (P>0. 05);HBeAg seroconversion rate in group C was significantly higher than those in group A and B (P0. 05). In the 48th week of combined therapy, HBsAg seroconversion rate in group C was higher than those in group A and B, but the differences were not statistically significant (P>0. 05), while the increasing tend-ency was obvious;HBeAg seroconversion rate in group C was significantly higher than those in group A and B ( P 0. 05);The difference in ALT normali-zation rate and HBV-DNA negative conversion rate were not statistically significant among the three groups (P>0. 05). During the treatment

  15. The Study on the Confirmatory Protocol of the Reactive Results of Hepatitis B Viral Surface Antigen Blood Screening Test%乙型肝炎病毒表面抗原血液复查阳性结果确认方案的研究

    Institute of Scientific and Technical Information of China (English)

    刘宇宁; 伍晓菲; 贾尧; 蔡菊英; 刘晓音; 王迅

    2011-01-01

    目的 为探讨简便、经济、可行的HBsAg阳性结果确认方案,为今后在检验常规工作中开展血液筛查阳性结果的确认奠定基础.方法 随机抽取2004~2006年奉贤区血站HBsAg检测不合格血浆标本441份,采用Murex、Organon、新创和科华酶标(EIA)试剂进行复检,对Murex复检为阳性的标本采用Murex中和试验进行确认,并对无法确认或确认为可疑的标本进行HBV DNA检测.结果经EIA复检、中和试验确认及HBV DNA检测,确认441份标本中406份为阳性,7份为可疑,28份为阴性.通过对4种EIA试剂阳性预期值和漏检情况的分析,发现其阳性预期值均达98.74%以上,试剂间差异无统计学意义,而漏检率分别为0.49%、4.19%、3.45%和9.36%,其差异无统计学意义.进一步分析发现,无论4种、3种或2种试剂组合检测,其阳性预期值的差异无统计学意义,但2种EIA试剂组合检测时,“Organon+新创”、“Organon+科华”、“新创十科华”组合的漏检率明显较其他组合为高.结论选择合适的2种EIA试剂组合检测,结果同时为阳性时,不必做中和试验而直接判断待检标本为真阳性,当2种试剂组合中其中一种为Murex时,能获得较高的确认效率.%Objective In order to explore a simple, economic and feasible protocol for confirming the reactive results of hepatitis B viral surface antigen (HBsAg) blood screening test, promote the application of the confirmatory assay in the routine blood screening program. Methods 441 samples were randomly selected from all the HBsAg unqualified samples from 2004 to 2006. Murex, Organon, Xinchuang and Kehua Biotech HBsAg El A reagents were used to re-test the samples. Murex reactive samples were confirmed by Murex HBsAg Confirmatory Assay. The samples only reactive to other 3 reagents and the indeterminate samples with confirmatory assay were further tested by HBV DNA PCR tests. Results After re-test, neutralised confirmatory assay and HBV DNA

  16. Positive Correlation between Epstein-Barr Virus Viral Load and Anti-Viral Capsid Immunoglobulin G Titers Determined for Hodgkin's Lymphoma Patients and Their Relatives

    Science.gov (United States)

    Besson, Caroline; Amiel, Corinne; Le-Pendeven, Catherine; Brice, Pauline; Fermé, Christophe; Carde, Patrice; Hermine, Olivier; Raphael, Martine; Abel, Laurent; Nicolas, Jean-Claude

    2006-01-01

    Markers of Epstein-Barr virus (EBV) infection include measures of specific serological titers and of viral load (VLo) in peripheral blood mononuclear cells. Few studies have investigated the correlation between these two phenotypes. Here, we found that there was no correlation between VLo and either anti-EBV nuclear antigen type 1 or anti-early antigen immunoglobulin G (IgG) titer but that anti-viral capsid antigen (VCA) IgG titer increased with VLo in peripheral blood mononuclear cells in patients with Hodgkin's lymphoma (P = 3.10−3). A similar pattern was observed in healthy first-degree relatives (parents and siblings) of patients (P = 6.10−4). Our results indicate that anti-VCA IgG titers and EBV VLo are specifically correlated EBV phenotypes. PMID:16390946

  17. [The vaccines based on the replicon of the venezuelan equine encephalomyelitis virus against viral hemorrhagic fevers].

    Science.gov (United States)

    Petrov, A A; Plekhanova, T M; Sidorova, O N; Borisevich, S V; Makhlay, A A

    2015-01-01

    The status of the various recombinant DNA and RNA-derived candidate vaccines, as well as the Venezuelan equine encephalomyelitis virus (VEEV) replicon vaccine system against extremely hazardous viral hemorrhagic fevers, were reviewed. The VEEV-based replication-incompetent vectors offer attractive features in terms of safety, high expression levels of the heterologous viral antigen, tropism to dendritic cells, robust immune responses, protection efficacy, low potential for pre-existing anti-vector immunity and possibility of engineering multivalent vaccines were tested. These features of the VEEV replicon system hold much promise for the development of new generation vaccine candidates against viral hemorrhagic fevers.

  18. VIRAL HEPATITIS E DIAGNOSTICS

    Directory of Open Access Journals (Sweden)

    E. Yu. Malinnikova

    2013-01-01

    Full Text Available Abstract. The results of clinical and epidemiological studies conducted in the M.P. Chumakov’ Research Institute of Poliomyelitis and Viral Encephalitis and in the different research institutions of the world have been summarized in the current article. Data on etiology, pathogenesis, clinical symptoms, epidemiology and prevention of hepatitis E are presented. Increasing of significance of this infection for health care system in Russia is emphasized . The actual problems of hepatitis E (autochthonic hepatitis E, hepatitis E as zoonosis, chronic hepatitis E are discussed.

  19. NK cell subset redistribution during the course of viral infections

    Directory of Open Access Journals (Sweden)

    Enrico eLugli

    2014-08-01

    Full Text Available Natural killer (NK cells are important effectors of innate immunity that play a critical role in the control of human viral infections. Indeed, given their capability to directly recognize virally infected cells without the need of specific antigen presentation, NK cells are on the first line of defense against these invading pathogens. By establishing cellular networks with a variety of cell types such as dendritic cells, NK cells can also amplify anti-viral adaptive immune responses. In turn, viruses evolved and developed several mechanisms to evade NK cell-mediated immune activity. It has been reported that certain viral diseases, including human immunodeficiency virus-1 (HIV-1 as well as cytomegalovirus (CMV infections, are associated with a pathologic redistribution of NK cell subsets in the peripheral blood. In particular, it has been observed the expansion of unconventional CD56neg NK cells, whose effector functions are significantly impaired as compared to that of conventional CD56pos NK cells. In this review, we address the impact of chronic viral infections on the functional and phenotypic perturbations of human NK cell compartment.

  20. Anti-Viral Antibody Profiling by High Density Protein Arrays

    Science.gov (United States)

    Bian, Xiaofang; Wiktor, Peter; Kahn, Peter; Brunner, Al; Khela, Amritpal; Karthikeyan, Kailash; Barker, Kristi; Yu, Xiaobo; Magee, Mitch; Wasserfall, Clive H.; Gibson, David; Rooney, Madeleine E; Qiu, Ji; LaBaer, Joshua

    2015-01-01

    Viral infections elicit anti-viral antibodies and have been associated with various chronic diseases. Detection of these antibodies can facilitate diagnosis, treatment of infection and understanding of the mechanisms of virus associated diseases. In this work, we assayed anti-viral antibodies using a novel high density-nucleic acid programmable protein array (HD-NAPPA) platform. Individual viral proteins were expressed in situ directly from plasmids encoding proteins in an array of microscopic reaction chambers. Quality of protein display and serum response was assured by comparing intra- and inter- array correlation within or between printing batches with average correlation coefficients of 0.91 and 0.96, respectively. HD-NAPPA showed higher signal to background (S/B) ratio compared with standard NAPPA on planar glass slides and ELISA. Antibody responses to 761 antigens from 25 different viruses were profiled among patients with juvenile idiopathic arthritis (JIA) and type 1 diabetes (T1D). Common as well as unique antibody reactivity patterns were detected between patients and healthy controls. We believe HD-viral-NAPPA will enable the study of host-pathogen interactions at unprecedented dimensions and elucidate the role of pathogen infections in disease development. PMID:25758251

  1. The Immune Response Induced by Hepatitis B Virus Principal Antigens

    Institute of Scientific and Technical Information of China (English)

    Chien-Fu Huang; Shih-Shen Lin; Yung-Chyuan Ho; Fong-Ling Chen; Chi-Chiang Yang

    2006-01-01

    Hepatitis B virus (HBV) infection occurs primarily in hepatocytes in the liver with release of infectious virions and non-infectious empty surface antigen particles into the bloodstream. HBV replication is non-cytopathic. Transient infections run a course of several months, and chronic infections are often life-long. Chronic infections can lead to liver failure with cirrhosis and hepatocellular carcinoma. It is generally accepted that neutralizing anti-HBs antibodies plays a key role in recovery from HBV infection by containing the spread of infection in the infected host and facilitating the removal and destruction of viral particles. However, the immune response initiated by the T-cell response to viral antigens is also important for viral clearance and disease pathogenesis in HBV infection.The three structural forms of the viral proteins, the HBsAg, the particulate HBcAg, and the nonparticulate HBeAg,may preferentially elicit different Th cell subsets. The different IgG subclass profiles of anti-HBs, anti-HBc, and anti-HBe in different HBV infection status were revealed. Moreover, the different IgG subclass profiles in chronic carriers did not change with different ALT and AST levels and may reflect the difference between stimulating antigens, immune response, and the stages of viral disease and provide the basis for the use of vaccines and prophylactic treatments for individuals at high risk of human HBV infection. This review elucidates the detailed understanding of the immune responses induced during transient and persistent infection, and the development of immunotherapy and immunodiagnosis in patients with HBV infection, and possible means of reducing the liver damage.

  2. Viral infections of rabbits.

    Science.gov (United States)

    Kerr, Peter J; Donnelly, Thomas M

    2013-05-01

    Viral diseases of rabbits have been used historically to study oncogenesis (e.g. rabbit fibroma virus, cottontail rabbit papillomavirus) and biologically to control feral rabbit populations (e.g. myxoma virus). However, clinicians seeing pet rabbits in North America infrequently encounter viral diseases although myxomatosis may be seen occasionally. The situation is different in Europe and Australia, where myxomatosis and rabbit hemorrhagic disease are endemic. Advances in epidemiology and virology have led to detection of other lapine viruses that are now recognized as agents of emerging infectious diseases. Rabbit caliciviruses, related to rabbit hemorrhagic disease, are generally avirulent, but lethal variants are being identified in Europe and North America. Enteric viruses including lapine rotavirus, rabbit enteric coronavirus and rabbit astrovirus are being acknowledged as contributors to the multifactorial enteritis complex of juvenile rabbits. Three avirulent leporid herpesviruses are found in domestic rabbits. A fourth highly pathogenic virus designated leporid herpesvirus 4 has been described in Canada and Alaska. This review considers viruses affecting rabbits by their clinical significance. Viruses of major and minor clinical significance are described, and viruses of laboratory significance are mentioned.

  3. Cytokine determinants of viral tropism

    OpenAIRE

    McFadden, Grant; Mohamed, Mohamed R.; Rahman, Masmudur M.; Bartee, Eric

    2009-01-01

    The specificity of a given virus for a ceil type, tissue or species — collectively known as viral tropism — is an important factor in determining the outcome of viral infection in any particular host. Owing to the increased prevalence of zoonotic infections and the threat of emerging and re-emerging pathogens, gaining a better understanding of the factors that determine viral tropism has become particularly important. In this Review, we summarize our current understanding of the central role ...

  4. Viral infections and cell cycle G2/M regulation

    Institute of Scientific and Technical Information of China (English)

    Richard Y.ZHAO; Robert T.ELDER

    2005-01-01

    Progression of cells from G2 phase of the cell cycle to mitosis is a tightly regulated cellular process that requires activation of the Cdc2 kinase, which determines onset of mitosis in all eukaryotic cells. In both human and fission yeast(Schizosaccharomyces pombe) cells, the activity of Cdc2 is regulated in part by the phosphorylation status of tyrosine 15(Tyr15) on Cdc2, which is phosphorylated by Wee1 kinase during late G2 and is rapidly dephosphorylated by the Cdc25 tyrosine phosphatase to trigger entry into mitosis. These Cdc2 regulators are the downstream targets of two well-characterized G2/M checkpoint pathways which prevent cells from entering mitosis when cellular DNA is damaged or when DNA replication is inhibited. Increasing evidence suggests that Cdc2 is also commonly targeted by viral proteins,which modulate host cell cycle machinery to benefit viral survival or replication. In this review, we describe the effect of viral protein R (Vpr) encoded by human immunodeficiency virus type 1 (HIV-1) on cell cycle G2/M regulation. Based on our current knowledge about this viral effect, we hypothesize that Vpr induces cell cycle G2 arrest through a mechanism that is to some extent different from the classic G2/M checkpoints. One the unique features distinguishing Vpr-induced G2 arrest from the classic checkpoints is the role of phosphatase 2A (PP2A) in Vpr-induced G2 arrest.Interestingly, PP2A is targeted by a number of other viral proteins including SV40 small T antigen, polyomavirus T antigen, HTLV Tax and adenovirus E4orf4. Thus an in-depth understanding of the molecular mechanisms underlying Vpr-induced G2 arrest will provide additional insights into the basic biology of cell cycle G2/M regulation and into the biological significance of this effect during host-pathogen interactions.

  5. Curation of viral genomes: challenges, applications and the way forward

    Directory of Open Access Journals (Sweden)

    Joshi Manali

    2006-12-01

    Full Text Available Abstract Background Whole genome sequence data is a step towards generating the 'parts list' of life to understand the underlying principles of Biocomplexity. Genome sequencing initiatives of human and model organisms are targeted efforts towards understanding principles of evolution with an application envisaged to improve human health. These efforts culminated in the development of dedicated resources. Whereas a large number of viral genomes have been sequenced by groups or individuals with an interest to study antigenic variation amongst strains and species. These independent efforts enabled viruses to attain the status of 'best-represented taxa' with the highest number of genomes. However, due to lack of concerted efforts, viral genomic sequences merely remained as entries in the public repositories until recently. Results VirGen is a curated resource of viral genomes and their analyses. Since its first release, it has grown both in terms of coverage of viral families and development of new modules for annotation and analysis. The current release (2.0 includes data for twenty-five families with broad host range as against eight in the first release. The taxonomic description of viruses in VirGen is in accordance with the ICTV nomenclature. A well-characterised strain is identified as a 'representative entry' for every viral species. This non-redundant dataset is used for subsequent annotation and analyses using sequenced-based Bioinformatics approaches. VirGen archives precomputed data on genome and proteome comparisons. A new data module that provides structures of viral proteins available in PDB has been incorporated recently. One of the unique features of VirGen is predicted conformational and sequential epitopes of known antigenic proteins using in-house developed algorithms, a step towards reverse vaccinology. Conclusion Structured organization of genomic data facilitates use of data mining tools, which provides opportunities for

  6. Antigenic breadth: a missing ingredient in HSV-2 subunit vaccines?

    Science.gov (United States)

    Halford, William P

    2014-06-01

    The successful human papillomavirus and hepatitis B virus subunit vaccines contain single viral proteins that represent 22 and 12%, respectively, of the antigens encoded by these tiny viruses. The herpes simplex virus 2 (HSV-2) genome is >20 times larger. Thus, a single protein subunit represents 1% of HSV-2's total antigenic breadth. Antigenic breadth may explain why HSV-2 glycoprotein subunit vaccines have failed in clinical trials, and why live HSV-2 vaccines that express 99% of HSV-2's proteome may be more effective. I review the mounting evidence that live HSV-2 vaccines offer a greater opportunity to stop the spread of genital herpes, and I consider the unfounded 'safety concerns' that have kept live HSV-2 vaccines out of U.S. clinical trials for 25 years.

  7. Resolving bovine viral diarrhea virus subtypes from persistently infected US beef calves with complete genome sequence

    Science.gov (United States)

    Bovine viral diarrhea virus (BVDV) is classified into 2 genotypes, BVDV-1 and BVDV-2, each of which contains distinct subtypes with genetic and antigenic differences. Currently, three major subtypes circulate in the United States: BVDV-1a, 1b, and 2a. In addition, a single case of BVDV-2b infection ...

  8. INDUCTION OF AUTOANTIBODIES TO HUMAN ENZYMES FOLLOWING VIRAL-INFECTION - A BIOLOGICALLY RELEVANT HYPOTHESIS

    NARCIS (Netherlands)

    WEIJERS, RNM; LAWSON, C; LEUNISSEN, J

    1992-01-01

    Macro enzymes, i. e. complexes of normal (iso-)enzymes with an immunoglobulin, may be due to immunological cross-reactions evoked by specific viral antigenic determinants that are homologous to regions in the target enzymes. A search of the National Biomedical Research Foundation protein databank wi

  9. Coping with viral diversity in HIV vaccine design.

    Directory of Open Access Journals (Sweden)

    David C Nickle

    2007-04-01

    Full Text Available The ability of human immunodeficiency virus type 1 (HIV-1 to develop high levels of genetic diversity, and thereby acquire mutations to escape immune pressures, contributes to the difficulties in producing a vaccine. Possibly no single HIV-1 sequence can induce sufficiently broad immunity to protect against a wide variety of infectious strains, or block mutational escape pathways available to the virus after infection. The authors describe the generation of HIV-1 immunogens that minimizes the phylogenetic distance of viral strains throughout the known viral population (the center of tree [COT] and then extend the COT immunogen by addition of a composite sequence that includes high-frequency variable sites preserved in their native contexts. The resulting COT(+ antigens compress the variation found in many independent HIV-1 isolates into lengths suitable for vaccine immunogens. It is possible to capture 62% of the variation found in the Nef protein and 82% of the variation in the Gag protein into immunogens of three gene lengths. The authors put forward immunogen designs that maximize representation of the diverse antigenic features present in a spectrum of HIV-1 strains. These immunogens should elicit immune responses against high-frequency viral strains as well as against most mutant forms of the virus.

  10. Viral causes of diarrhea.

    Science.gov (United States)

    Goodgame, R W

    2001-09-01

    Viruses are important causes of diarrhea. In healthy adults, the main clinical manifestation is acute, self-limited gastroenteritis. Advances in molecular diagnostics have shown that epidemics of acute gastroenteritis most frequently are due to caliciviruses spread through contaminated food or through person-to-person contact. Application of similar technology is needed to make a definitive statement about the role of such candidate viruses as rotavirus, astrovirus, and adenovirus as the cause of nonepidemic acute gastroenteritis in adults. Rarely a previously healthy adult gets acute CMV colitis. CMV and EBV mainly cause diarrhea in immunocompromised patients, however. Advances in prophylaxis and treatment have reduced the frequency and severity of these diseases. Acute infantile gastroenteritis is caused by rotavirus, calcivirus, astrovirus, and adenovirus. These viral diseases of the gut are seen by the physician as routine and rare clinical problems.

  11. Viral quasispecies evolution.

    Science.gov (United States)

    Domingo, Esteban; Sheldon, Julie; Perales, Celia

    2012-06-01

    Evolution of RNA viruses occurs through disequilibria of collections of closely related mutant spectra or mutant clouds termed viral quasispecies. Here we review the origin of the quasispecies concept and some biological implications of quasispecies dynamics. Two main aspects are addressed: (i) mutant clouds as reservoirs of phenotypic variants for virus adaptability and (ii) the internal interactions that are established within mutant spectra that render a virus ensemble the unit of selection. The understanding of viruses as quasispecies has led to new antiviral designs, such as lethal mutagenesis, whose aim is to drive viruses toward low fitness values with limited chances of fitness recovery. The impact of quasispecies for three salient human pathogens, human immunodeficiency virus and the hepatitis B and C viruses, is reviewed, with emphasis on antiviral treatment strategies. Finally, extensions of quasispecies to nonviral systems are briefly mentioned to emphasize the broad applicability of quasispecies theory.

  12. Role of metalloproteases in vaccinia virus epitope processing for transporter associated with antigen processing (TAP)-independent human leukocyte antigen (HLA)-B7 class I antigen presentation.

    Science.gov (United States)

    Lorente, Elena; García, Ruth; Mir, Carmen; Barriga, Alejandro; Lemonnier, François A; Ramos, Manuel; López, Daniel

    2012-03-23

    The transporter associated with antigen processing (TAP) translocates the viral proteolytic peptides generated by the proteasome and other proteases in the cytosol to the endoplasmic reticulum lumen. There, they complex with nascent human leukocyte antigen (HLA) class I molecules, which are subsequently recognized by the CD8(+) lymphocyte cellular response. However, individuals with nonfunctional TAP complexes or tumor or infected cells with blocked TAP molecules are able to present HLA class I ligands generated by TAP-independent processing pathways. Herein, using a TAP-independent polyclonal vaccinia virus-polyspecific CD8(+) T cell line, two conserved vaccinia-derived TAP-independent HLA-B*0702 epitopes were identified. The presentation of these epitopes in normal cells occurs via complex antigen-processing pathways involving the proteasome and/or different subsets of metalloproteinases (amino-, carboxy-, and endoproteases), which were blocked in infected cells with specific chemical inhibitors. These data support the hypothesis that the abundant cellular proteolytic systems contribute to the supply of peptides recognized by the antiviral cellular immune response, thereby facilitating immunosurveillance. These data may explain why TAP-deficient individuals live normal life spans without any increased susceptibility to viral infections.

  13. IFN-Gamma Inhibits JC Virus Replication in Glial Cells by Suppressing T-Antigen Expression.

    Directory of Open Access Journals (Sweden)

    Francesca Isabella De-Simone

    Full Text Available Patients undergoing immune modulatory therapies for the treatment of autoimmune diseases such as multiple sclerosis, and individuals with an impaired-immune system, most notably AIDS patients, are in the high risk group of developing progressive multifocal leukoencephalopathy (PML, an often lethal disease of the brain characterized by lytic infection of oligodendrocytes in the central nervous system (CNS with JC virus (JCV. The immune system plays an important regulatory role in controlling JCV reactivation from latent sites by limiting viral gene expression and replication. However, little is known regarding the molecular mechanisms responsible for this regulation.Here, we investigated the impact of soluble immune mediators secreted by activated PBMCs on viral replication and gene expression by cell culture models and molecular virology techniques. Our data revealed that viral gene expression and viral replication were suppressed by soluble immune mediators. Further studies demonstrated that soluble immune mediators secreted by activated PBMCs inhibit viral replication induced by T-antigen, the major viral regulatory protein, by suppressing its expression in glial cells. This unexpected suppression of T-antigen was mainly associated with the suppression of translational initiation. Cytokine/chemokine array studies using conditioned media from activated PBMCs revealed several candidate cytokines with possible roles in this regulation. Among them, only IFN-γ showed a robust inhibition of T-antigen expression. While potential roles for IFN-β, and to a lesser extent IFN-α have been described for JCV, IFN-γ has not been previously implicated. Further analysis of IFN-γ signaling pathway revealed a novel role of Jak1 signaling in control of viral T-antigen expression. Furthermore, IFN-γ suppressed JCV replication and viral propagation in primary human fetal glial cells, and showed a strong anti-JCV activity.Our results suggest a novel role for

  14. Rabies viral encephalitis with proable 25 year incubation period!

    Directory of Open Access Journals (Sweden)

    S K Shankar

    2012-01-01

    Full Text Available We report a case of rabies viral encephalitis in a 48-year-old male with an unusually long incubation period, historically suspected to be more than 20 years. The case was referred for histological diagnosis following alleged medical negligence to the forensic department. The histology and immunocytochemical demonstration of rabies viral antigen established the diagnosis unequivocally. The case manifested initially with hydrophobia and aggressive behavior, although he suddenly went to the bathroom and drank a small amount of water. History of dog bite 25 years back was elicited retrospectively following clinical suspicion. There was no subsequent history to suggest nonbite exposure to a rabid dog to consider recent event causing the disease, although this cannot be totally excluded.

  15. Sphingolipids in viral infection.

    Science.gov (United States)

    Schneider-Schaulies, Jürgen; Schneider-Schaulies, Sibylle

    2015-06-01

    Viruses exploit membranes and their components such as sphingolipids in all steps of their life cycle including attachment and membrane fusion, intracellular transport, replication, protein sorting and budding. Examples for sphingolipid-dependent virus entry are found for: human immunodeficiency virus (HIV), which besides its protein receptors also interacts with glycosphingolipids (GSLs); rhinovirus, which promotes the formation of ceramide-enriched platforms and endocytosis; or measles virus (MV), which induces the surface expression of its own receptor CD150 via activation of sphingomyelinases (SMases). While SMase activation was implicated in Ebola virus (EBOV) attachment, the virus utilizes the cholesterol transporter Niemann-Pick C protein 1 (NPC1) as 'intracellular' entry receptor after uptake into endosomes. Differential activities of SMases also affect the intracellular milieu required for virus replication. Sindbis virus (SINV), for example, replicates better in cells lacking acid SMase (ASMase). Defined lipid compositions of viral assembly and budding sites influence virus release and infectivity, as found for hepatitis C virus (HCV) or HIV. And finally, viruses manipulate cellular signaling and the sphingolipid metabolism to their advantage, as for example influenza A virus (IAV), which activates sphingosine kinase 1 and the transcription factor NF-κB.

  16. Dengue viral infections

    Directory of Open Access Journals (Sweden)

    Gurugama Padmalal

    2010-01-01

    Full Text Available Dengue viral infections are one of the most important mosquito-borne diseases in the world. Presently dengue is endemic in 112 countries in the world. It has been estimated that almost 100 million cases of dengue fever and half a million cases of dengue hemorrhagic fever (DHF occur worldwide. An increasing proportion of DHF is in children less than 15 years of age, especially in South East and South Asia. The unique structure of the dengue virus and the pathophysiologic responses of the host, different serotypes, and favorable conditions for vector breeding have led to the virulence and spread of the infections. The manifestations of dengue infections are protean from being asymptomatic to undifferentiated fever, severe dengue infections, and unusual complications. Early recognition and prompt initiation of appropriate supportive treatment are often delayed resulting in unnecessarily high morbidity and mortality. Attempts are underway for the development of a vaccine for preventing the burden of this neglected disease. This review outlines the epidemiology, clinical features, pathophysiologic mechanisms, management, and control of dengue infections.

  17. Emerging zoonotic viral diseases.

    Science.gov (United States)

    Wang, L-F; Crameri, G

    2014-08-01

    Zoonotic diseases are infectious diseases that are naturally transmitted from vertebrate animals to humans and vice versa. They are caused by all types of pathogenic agents, including bacteria, parasites, fungi, viruses and prions. Although they have been recognised for many centuries, their impact on public health has increased in the last few decades due to a combination of the success in reducing the spread of human infectious diseases through vaccination and effective therapies and the emergence of novel zoonotic diseases. It is being increasingly recognised that a One Health approach at the human-animal-ecosystem interface is needed for effective investigation, prevention and control of any emerging zoonotic disease. Here, the authors will review the drivers for emergence, highlight some of the high-impact emerging zoonotic diseases of the last two decades and provide examples of novel One Health approaches for disease investigation, prevention and control. Although this review focuses on emerging zoonotic viral diseases, the authors consider that the discussions presented in this paper will be equally applicable to emerging zoonotic diseases of other pathogen types.

  18. Generation of Recombinant Viral Hemorrhagic Septicemia Virus (rVHSV) Expressing Two Foreign Proteins and Effect of Lengthened Viral Genome on Viral Growth and In Vivo Virulence.

    Science.gov (United States)

    Kim, Min Sun; Lee, Su Jin; Kim, Dong Soo; Kim, Ki Hong

    2016-04-01

    In this study, a new recombinant VHSV (rVHSV-Arfp-Bgfp) was generated by insertion of a red fluorescent protein (RFP) gene between N and P genes, a green fluorescent protein (GFP) gene between P and M genes of VHSV genome, the expression of each heterologous gene in infected cells, and effects of the lengthened recombinant VHSV's genome on the replication ability and in vivo virulence to olive flounder (Paralichthys olivaceus) fingerlings were compared with previously generated rVHSVs (rVHSV-wild, rVHSV-Arfp, and rVHSV-Brfp). The expression of RFP and GFP in cells infected with rVHSV-Arfp-Bgfp was verified through fluorescent microscopy and FACS analysis. In the viral growth analysis, rVHSV-Arfp and rVHSV-Brfp showed significantly lower viral titers than rVHSV-wild, and the replication of rVHSV-Arfp-Bgfp was significantly decreased compared to that of even rVHSV-Arfp or rVHSV-Brfp. These results suggest that the genome length is a critical factor for the determination of rVHSVs replication efficiency. In the in vivo virulence experiment, the cumulative mortalities of olive flounder fingerlings infected with each rVHSV were inversely proportional to the length of the viral genome, suggesting that decreased viral growth rate due to the lengthened viral genome is accompanied with the decrease of in vivo virulence of rVHSVs. Recombinant viruses expressing multiple foreign antigens can be used for the development of combined vaccines. However, as the present rVHSV-Arfp-Bgfp still possesses an ability to kill hosts (although very weakened), researches on the producing more attenuated viruses or propagation-deficient replicon particles are needed to solve safety-related problems.

  19. [Clinical benefit of HCV core antigen assay in patients receiving interferon and ribavirin combination therapy].

    Science.gov (United States)

    Higashimoto, Makiko; Takahashi, Masahiko; Jokyu, Ritsuko; Saito, Hidetsugu

    2006-02-01

    A highly sensitive second generation HCV core antigen assay has recently been developed. We compared viral disappearance and kinetics data between commercially available core antigen assays, Lumipulse Ortho HCV Ag, and a quantitative HCV RNA PCR assay, Cobas Amplicor HCV Monitor Test, Version 2 to estimate the predictive benefit of sustained viral response (SVR) and non-SVR in 59 patients treated with interferon and ribavirin combination therapy. We found a good correlation between HCV core Ag and HCV RNA level regardless of genotype. Although the sensitivity of the core antigen assay was lower than PCR, the dynamic range was broader than that of the PCR assay, so that we did not need to dilute the samples in 59 patients. We detected serial decline of core Ag levels in 24 hrs, 7 days and 14 days after interferon combination therapy. The decline of core antigen levels was significant in SVR patients compared to non-SVR as well as in genotype 2a, 2b patients compared to 1b. Core antigen-negative on day 1 could predict all 10 SVR patients (PPV = 100%), whereas RNA-negative could predict 22 SVR out of 25 on day 14 (PPV = 88.0%). None of the patients who had detectable serum core antigen on day 14 became SVR(NPV = 100%), although NPV was 91.2% on RNA negativity. An easy, simple, low cost new HCV core antigen detecting system seems to be useful for assessing and monitoring IFN treatment for HCV.

  20. PREVALENCE OF DIFFERENT VIRAL MARKERS IN PATIENTS OF ACUTE VIRAL HEPATITIS IN AND AROUND VISAKHAPATNAM : HOSPITAL BASED STUDY

    Directory of Open Access Journals (Sweden)

    Aruna Sree

    2015-04-01

    Full Text Available Acute viral hepatitis (AVH is a major public health problem and is an important cause of morbidity and mortality in the developing countries. AIM: The aim of the present study is to study the serological profile of acute viral hepatitis in children and adults admitted in King George Hospital, Visakhapatnam and also age and sex distribution of patients suffering from acute viral hepatitis and also comparing the etiological profile by studying serological markers of common viral agents. SUBJECTS AND METHODS: Samples were collected from 80 individuals with jaundice and other clinical and biochemical evidences of acute viral hepatitis . They were tested for hepatitis surface antigen, HBcIgM, HAVIgM, HEVIgM, Antibodies to HCV by the enzyme - linked immuno sorbent assay. RESULTS: Out of the 80 viral hepatitis cases (47 adults+33 children. In adults 20(42.5% patients presented HBV (26.96% was identified as the most common cause of acute hepatitis followed by HEV14 (29.8%, HEV+HAV4 (8.5% and HAV 6(12.76%. Co - infections with more than one virus were present in 5cases; HAV - HEV co - infection being the most common. In children 16(48.5% presented with HAV, HAV+HEV11 (33.3%, HEV4 (12.12%, HBV1 (3.03% CONCLUSIONS: Vaccination of adults against hepatitis B is indicated, along with sexual education to decrease the incidence of hepatitis which is found as common etiological agent in adults. The incidence of HAV and HEV in children shows that there is need for improvement in sanitation and food habits.

  1. Encefalitis virales en la infancia

    OpenAIRE

    2013-01-01

    La encefalitis viral es una enfermedad grave que implica el compromiso inflamatorio del parénquima cerebral. Las infecciones virales del SNC ocurren con frecuencia como complicación de infecciones virales sistémicas. Más de 100 virus están implicados como agentes causales, entre los cuales el virus Herpes simplex tipo I, es el agente causal más frecuente de encefalitis no epidémica en todos los grupos poblacionales del mundo; es el responsable de los casos más graves en todas las edades. Much...

  2. Enfermedades virales emergentes y reemergentes

    OpenAIRE

    Jorge Eliécer Ossa Londoño; Ana Isabel Toro Montoya

    1996-01-01

    Los virus no son una excepción al principio de que toda forma de vida de hoyes el producto de la evolución de información gen ética preexistente. Tradicionalmente se ha reconocido que ta expresión clínica de las enfermedades virales cambia con el tiempo; molecularmente se ha demostrado que esos cambios fenotípicos son el producto de variaciones en el genoma viral. La tasa de cambio
    gen ético y fenotípico no es la misma en todos los agentes virales y ello está determinado, principal...

  3. HLA-KIR Interactions and Immunity to Viral Infections

    Directory of Open Access Journals (Sweden)

    Masoud Sabouri Ghannad

    2014-02-01

    Full Text Available Host genetic factors play a central role in determining the clinical phenotype of human diseases. Association between two polymorphic loci in human genome, human leukocyte antigen (HLA and killer cell immunoglobulin-like receptors (KIRs, and genetically complex infectious disease, particularly those of viral etiology, have been historically elusive. Hence, defining the influence of genetic diversity in HLA and KIRs on the outcome of viral infections has been extensively started in clinically well-defined cohort studies. HLA genes encode molecules which present antigenic peptide fragments to T lymphocytes as central players in adaptive immunity against infectious diseases. KIRs are expressed on natural killer cells which perform a crucial role in innate immunity to pathogen infection. The effector functions of NK cells such as direct killing of infected cells, cytokine production, and cross-talk with adaptive immune system depend on activation of NK cells, which is determined by their surface receptors. Among these receptors, KIRs, which interact with HLA class I, are mainly inhibitory and exhibit substantial genetic diversity. An extensive body of association studies indicates a role for HLA–KIRs interactions in infectious diseases, autoimmune disorders, cancer, transplantation, and reproduction. Various compound HLA-KIR genotypes appear to affect outcome of viral infections that suggests a role for HLA class I diversity in innate immunity as well as adaptive immune responses. The aim of this review is focusing on the impact of HLA and KIR alleles and different combinations of these alleles on clinical outcome of viral diseases to validate this proof-of-concept with respect to the therapeutic interventions.

  4. Crystal structure of a human rhinovirus neutralizing antibody complexed with a peptide derived from viral capsid protein VP2.

    OpenAIRE

    1994-01-01

    The three-dimensional structure of the complex between the Fab fragment of an anti-human rhinovirus neutralizing antibody (8F5) and a cross-reactive synthetic peptide from the viral capsid protein VP2 has been determined at 2.5 A resolution by crystallographic methods. The refinement is presently at an R factor of 0.18 and the antigen-binding site and viral peptide are well defined. The peptide antigen adopts a compact fold by two tight turns and interacts through hydrogen bonds, some with io...

  5. Familial occurrence of subacute thyroiditis associated with human leukocyte antigen-B35

    NARCIS (Netherlands)

    Kramer, AB; Roozendaal, C; Dullaart, RPF

    2004-01-01

    Subacute thyroiditis (SAT) is a spontaneously remitting inflammatory disorder of the thyroid, associated with human leukocyte antigen (HLA)-B35, and may be virally induced in genetically predisposed individuals. A 57-year-old Caucasian man presented with symptoms of hyperthyroidism as well as enlarg

  6. African swine fever virus serotype-specific proteins are significant protective antigens for African swine fever

    Science.gov (United States)

    African swine fever (ASF) is an emerging disease threat for the swine industry worldwide. No ASF vaccine is available and progress is hindered by lack of knowledge concerning the extent of African swine fever virus (ASFV) strain diversity and the viral antigens conferring type specific protective im...

  7. Pulmonary major histocompatability complex expression pattern is suggestive of the characteristics of airway antigen

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ An X-ray film is capable of showing that bacterial infection, viral infection, and non-microbial antigens may all cause infiltrations in the chest. To judge what reason is exactly responsible for the shadows in the film poses a challenge for medical staffs, and this problem can be further complicated by newly discovered pathogens and microbes that need to be further discovered.

  8. Neuroanatomy goes viral!

    Directory of Open Access Journals (Sweden)

    Jonathan eNassi

    2015-07-01

    Full Text Available The nervous system is complex not simply because of the enormous number of neurons it contains but by virtue of the specificity with which they are connected. Unraveling this specificity is the task of neuroanatomy. In this endeavor, neuroanatomists have traditionally exploited an impressive array of tools ranging from the Golgi method to electron microscopy. An ideal method for studying anatomy would label neurons that are interconnected, and, in addition, allow expression of foreign genes in these neurons. Fortuitously, nature has already partially developed such a method in the form of neurotropic viruses, which have evolved to deliver their genetic material between synaptically connected neurons while largely eluding glia and the immune system. While these characteristics make some of these viruses a threat to human health, simple modifications allow them to be used in controlled experimental settings, thus enabling neuroanatomists to trace multi-synaptic connections within and across brain regions. Wild-type neurotropic viruses, such as rabies and alpha-herpes virus, have already contributed greatly to our understanding of brain connectivity, and modern molecular techniques have enabled the construction of recombinant forms of these and other viruses. These newly engineered reagents are particularly useful, as they can target genetically defined populations of neurons, spread only one synapse to either inputs or outputs, and carry instructions by which the targeted neurons can be made to express exogenous proteins, such as calcium sensors or light-sensitive ion channels, that can be used to study neuronal function. In this review, we address these uniquely powerful features of the viruses already in the neuroanatomist's toolbox, as well as the aspects of their biology that currently limit their utility. Based on the latter, we consider strategies for improving viral tracing methods by reducing toxicity, improving control of transsynaptic

  9. Statistical mechanics of viral entry.

    Science.gov (United States)

    Zhang, Yaojun; Dudko, Olga K

    2015-01-09

    Viruses that have lipid-membrane envelopes infect cells by fusing with the cell membrane to release viral genes. Membrane fusion is known to be hindered by high kinetic barriers associated with drastic structural rearrangements-yet viral infection, which occurs by fusion, proceeds on remarkably short time scales. Here, we present a quantitative framework that captures the principles behind the invasion strategy shared by all enveloped viruses. The key to this strategy-ligand-triggered conformational changes in the viral proteins that pull the membranes together-is treated as a set of concurrent, bias field-induced activated rate processes. The framework results in analytical solutions for experimentally measurable characteristics of virus-cell fusion and enables us to express the efficiency of the viral strategy in quantitative terms. The predictive value of the theory is validated through simulations and illustrated through recent experimental data on influenza virus infection.

  10. Viral marketing as epidemiological model

    CERN Document Server

    Rodrigues, Helena Sofia

    2015-01-01

    In epidemiology, an epidemic is defined as the spread of an infectious disease to a large number of people in a given population within a short period of time. In the marketing context, a message is viral when it is broadly sent and received by the target market through person-to-person transmission. This specific marketing communication strategy is commonly referred as viral marketing. Due to this similarity between an epidemic and the viral marketing process and because the understanding of the critical factors to this communications strategy effectiveness remain largely unknown, the mathematical models in epidemiology are presented in this marketing specific field. In this paper, an epidemiological model SIR (Susceptible- Infected-Recovered) to study the effects of a viral marketing strategy is presented. It is made a comparison between the disease parameters and the marketing application, and simulations using the Matlab software are performed. Finally, some conclusions are given and their marketing impli...

  11. FastStats: Viral Hepatitis

    Science.gov (United States)

    ... Submit What's this? Submit Button NCHS Home Viral Hepatitis Recommend on Facebook Tweet Share Compartir Data are for the U.S. Morbidity Number of new hepatitis A cases: 1,781 (2013) Number of new ...

  12. Aseptic meningitis and viral myelitis.

    Science.gov (United States)

    Irani, David N

    2008-08-01

    Meningitis and myelitis represent common and very infrequent viral infections of the central nervous system, respectively. The number of cases of viral meningitis that occurs annually exceeds the total number of meningitis cases caused by all other etiologies combined. Focal central nervous system infections, such as occur in the spinal cord with viral myelitis, are much less common and may be confused with noninfectious disorders that cause acute flaccid paralysis. This article reviews some of the important clinical features, epidemiology, diagnostic approaches, and management strategies for patients with aseptic meningitis and viral myelitis. Particular focus is placed on the diseases caused by enteroviruses, which as a group account for most aseptic meningitis cases and many focal infections of the spinal cord.

  13. The role of respiratory syncytial virus and other viral pathogens in acute otitis media.

    Science.gov (United States)

    Klein, B S; Dollete, F R; Yolken, R H

    1982-07-01

    We utilized recently developed enzyme immunoassay techniques to examine the role of selected viruses in the etiology of acute otitis media. Viral pathogens were found in middle ear fluids obtained from 13 (24%) of 53 children with acute otitis media; respiratory syncytial virus accounted for ten of the 13 viral agents identified. In addition, respiratory syncytial viral antigen was found in nasopharyngeal washings obtained from 15 of the 53 children. Seven of these children had RSV identified as the sole middle ear pathogen, whereas six children had otitis caused by Streptococcus pneumoniae as either the sole middle ear pathogen or in combination with RSV. Similarly, all three children with respiratory infections caused by influenza virus had ear infections caused by bacterial pathogens, either alone or in combination with influenza virus. These findings suggest that, in patients with viral respiratory infection, coexisting acute otitis media may be associated with the recovery of either viruses or bacteria from the middle ear exudates.

  14. Microbiological diagnostics of viral hepatitis

    OpenAIRE

    HASDEMİR, Ufuk

    2016-01-01

    Viral hepatitis is an infection that primarily affects the liverbut may also have systemic clinical manifestations. The vastmajority of viral hepatitis are caused by one of five hepatotropicviruses: hepatitis A virus (HAV), hepatitis B virus (HBV),hepatitis C virus (HCV), hepatitis D (delta) virus (HDV), andhepatitis E virus (HEV) (Table I) [1]. HBV, HCV, and HDValso cause chronic hepatitis, whereas HAV does not. HEVcauses acute hepatitis in normal hosts but can cause protractedand chronic he...

  15. Viral RNAs are unusually compact.

    Directory of Open Access Journals (Sweden)

    Ajaykumar Gopal

    Full Text Available A majority of viruses are composed of long single-stranded genomic RNA molecules encapsulated by protein shells with diameters of just a few tens of nanometers. We examine the extent to which these viral RNAs have evolved to be physically compact molecules to facilitate encapsulation. Measurements of equal-length viral, non-viral, coding and non-coding RNAs show viral RNAs to have among the smallest sizes in solution, i.e., the highest gel-electrophoretic mobilities and the smallest hydrodynamic radii. Using graph-theoretical analyses we demonstrate that their sizes correlate with the compactness of branching patterns in predicted secondary structure ensembles. The density of branching is determined by the number and relative positions of 3-helix junctions, and is highly sensitive to the presence of rare higher-order junctions with 4 or more helices. Compact branching arises from a preponderance of base pairing between nucleotides close to each other in the primary sequence. The density of branching represents a degree of freedom optimized by viral RNA genomes in response to the evolutionary pressure to be packaged reliably. Several families of viruses are analyzed to delineate the effects of capsid geometry, size and charge stabilization on the selective pressure for RNA compactness. Compact branching has important implications for RNA folding and viral assembly.

  16. A pathogenetic study of the early connective tissue lesions of viral caprine arthritis-encephalitis.

    Science.gov (United States)

    Adams, D S; Crawford, T B; Klevjer-Anderson, P

    1980-05-01

    Experiments were designed to correlate morphologic lesions with the presence of caprine arthritis-encephalitis virus (CAEV). Twenty-one cesarean-derived goat kids were infected with 10(6) to 10(7) TCID50 of virus, killed sequentially, and examined for viral antigens by immunofluorescence, viral infectivity by isolation and titration, and morphologic changes by light microscopy. Fluorescent viral antigens were detected from 1 to 10 days postinoculation (DPI) and only in synovial cells. Virus was reisolated from several joints and from brain 0.5 to 79 DPI. Increases in synovial fluid cell counts were noted by 1 DPI, and morphologic changes in synovial membranes were present from 3 to 45 DPI. Joint lesions progressed from mild synovial cell hyperplasia and perivascular mononuclear cell infiltration to severe synovial cell hyperplasia and mononuclear cell infiltration with villous hypertrophy. Lesions elsewhere were mild, consisting only of perivascular mononuclear cell infiltrates. Eleven cesarean-derived control goats were negative for viral antigens, virus, and morphologic lesions.

  17. Computer analysis of antigenic domains and RGD-like sequences (RGWG) in the E glycoprotein of flaviviruses: an approach to vaccine development.

    Science.gov (United States)

    Becker, Y

    1990-09-01

    Antigenic domains and RGD-like sequences in the E glycoprotein of the flaviviruses Japanese encephalitis virus, yellow fever virus, West Nile virus, dengue type 4 virus, and tick-borne encephalitis virus were analyzed by computer programs that provide information on the physical properties of the polypeptides. The use of computer programs for the development of vaccines based on the synthesis of antigenic peptides is discussed. Synthetic viral peptides are proposed to be used for topical application so as to interfere with the virus-cell interaction. Viral peptides with antigenic epitopes to protect against dengue virus infection without enhancing pathogenesis may also be developed on the basis of the computer analysis.

  18. [Neuropsychiatric sequelae of viral meningitis in adults].

    Science.gov (United States)

    Damsgaard, Jesper; Hjerrild, Simon; Renvillard, Signe Groth; Leutscher, Peter Derek Christian

    2011-10-10

    Viral meningitis is considered to be a benign illness with only mild symptoms. In contrast to viral encephalitis and bacterial meningitis, the prognosis is usually good. However, retrospective studies have demonstrated that patients suffering from viral meningitis may experience cognitive impairment following the acute course of infection. Larger controlled studies are needed to elucidate the potential neuropsychiatric adverse outcome of viral meningitis.

  19. Hepatitis B virus: pathogenesis, viral intermediates, and viral replication.

    Science.gov (United States)

    Lee, Jia-Yee; Locarnini, Stephen

    2004-05-01

    Although HBV has the potential to generate an almost limitless spectrum of quasispecies during chronic infection, the viability of the majority of these quasispecies is almost certainly impaired due to constraints imposed by the remarkably compact organization of the HBV genome. On the other hand, single mutations may affect more than one gene and result in complex and unpredictable effects on viral phenotype. Better understanding of the constraints imposed by gene overlap and of genotype-phenotype relationships should help in the development of improved antiviral strategies and management approaches. Although the probability of developing viral resistance is directly proportional to the intensity of selection pressure and the diversity of quasispecies, potent inhibition of HBV replication should be able to prevent development of drug resistance because mutagenesis is replication dependent. If viral replication can be suppressed for a sufficient length of time, viral load should decline to a point where the continued production of quasispecies with the potential to resist new drug treatments no longer occurs. Clinical application of this concept will require optimization of combination therapies analogous to highly active antiretroviral therapy (HAART) for HIV infection. Total cure of hepatitis B will require elimination of the intranuclear pool of viral minichromosomes, which will probably only be achieved by normal cell turnover, reactivation of host immunity, or elucidation of the antiviral mechanisms operating during cytokine clearance in acute hepatitis B (see Fig. 1).

  20. [Pathology and viral metagenomics, a recent history].

    Science.gov (United States)

    Bernardo, Pauline; Albina, Emmanuel; Eloit, Marc; Roumagnac, Philippe

    2013-05-01

    Human, animal and plant viral diseases have greatly benefited from recent metagenomics developments. Viral metagenomics is a culture-independent approach used to investigate the complete viral genetic populations of a sample. During the last decade, metagenomics concepts and techniques that were first used by ecologists progressively spread into the scientific field of viral pathology. The sample, which was first for ecologists a fraction of ecosystem, became for pathologists an organism that hosts millions of microbes and viruses. This new approach, providing without a priori high resolution qualitative and quantitative data on the viral diversity, is now revolutionizing the way pathologists decipher viral diseases. This review describes the very last improvements of the high throughput next generation sequencing methods and discusses the applications of viral metagenomics in viral pathology, including discovery of novel viruses, viral surveillance and diagnostic, large-scale molecular epidemiology, and viral evolution.

  1. Cancer testis antigen and immunotherapy

    Directory of Open Access Journals (Sweden)

    Krishnadas DK

    2013-04-01

    Full Text Available Deepa Kolaseri Krishnadas, Fanqi Bai, Kenneth G Lucas Department of Pediatrics, Division of Hematology/Oncology, University of Louisville, KY, USA Abstract: The identification of cancer testis (CT antigens has been an important advance in determining potential targets for cancer immunotherapy. Multiple previous studies have shown that CT antigen vaccines, using both peptides and dendritic cell vaccines, can elicit clinical and immunologic responses in several different tumors. This review details the expression of melanoma antigen family A, 1 (MAGE-A1, melanoma antigen family A, 3 (MAGE-A3, and New York esophageal squamous cell carcinoma-1 (NY-ESO-1 in various malignancies, and presents our current understanding of CT antigen based immunotherapy. Keywords: cancer testis antigens, immunotherapy, vaccine

  2. Specific mutation of a gammaherpesvirus-expressed antigen in response to CD8 T cell selection in vivo.

    Science.gov (United States)

    Loh, Joy; Popkin, Daniel L; Droit, Lindsay; Braaten, Douglas C; Zhao, Guoyan; Zhang, Xin; Vachharajani, Punit; Myers, Nancy; Hansen, Ted H; Virgin, Herbert W

    2012-03-01

    Herpesviruses are thought to be highly genetically stable, and their use as vaccine vectors has been proposed. However, studies of the human gammaherpesvirus, Epstein-Barr virus, have found viral isolates containing mutations in HLA class I-restricted epitopes. Using murine gammaherpesvirus 68 expressing ovalbumin (OVA), we examined the stability of a gammaherpesvirus antigenic locus under strong CD8 T cell selection in vivo. OVA-specific CD8 T cells selected viral isolates containing mutations in the OVA locus but minimal alterations in other genomic regions. Thus, a CD8 T cell response to a gammaherpesvirus-expressed antigen that is not essential for replication or pathogenesis can result in selective mutation of that antigen in vivo. This finding may have relevance for the use of herpesvirus vectors for chronic antigen expression in vivo.

  3. Expression of P20 and P14 protein genes of bovine viral diarrhea virus and antigenicity analysis of the expressed proteins%牛病毒性腹泻病毒P20及P14蛋白基因的表达及其产物的抗原性分析

    Institute of Scientific and Technical Information of China (English)

    李慧昕; 王君伟

    2006-01-01

    将牛病毒性腹泻病毒(bovine viral diarrhea virus,BVDV)p20和p14基因分别亚克隆至原核表达载体pGEX-6p-1和pPROEX-HTb,并转化至相应的宿主菌大肠杆菌BL21(DE3)pLysS和DH5α中表达.P20蛋白在2个宿主中都获得了高效表达;P14蛋白在BL21(DE3)pLysS中表达量较低,而在DH5α中未见表达.对P14蛋白诱导表达过程的监测表明,P14蛋白对大肠杆菌是一种毒性蛋白.用Western-blotting分析未能检测到两种蛋白的反应条带,推测这两种蛋白可能存在构象表位.

  4. No evidence of an increase of bacterial and viral infections following Measles, Mumps and Rubella vaccine.

    Science.gov (United States)

    Stowe, Julia; Andrews, Nick; Taylor, Brent; Miller, Elizabeth

    2009-02-25

    The suggestion that multi-antigen vaccines might overload the immune system has led to calls for single antigen vaccines. In 2003 we showed that rather than an increase there appeared to be a reduced risk of severe bacterial infection in the three months following Measles, Mumps and Rubella vaccine (MMR). The present analysis of illnesses in a general population is based on an additional 10 years of data for bacterial infections and also includes admissions with viral infections. Analyses were carried out using the self-controlled case-series method and separately for bacterial and viral infection cases, using risk periods of 0-30 days, 31-60 days and 61-90 days post MMR vaccine. An analysis was also carried out for those cases which were given MMR and Meningococcal serogroup C (MCC) vaccines concomitantly. A reduced risk was seen in the 0-30-day period for both bacterial infection (relative incidence=0.68, 95% CI 0.54-0.86) and viral infections (relative incidence=0.68, 95% CI 0.49-0.93). There was no increased risk in any period when looking at combined viral or bacterial infections or for individual infections with the single exception of an increased risk in the 31-60 days post vaccination period for herpes infections (relative incidence=1.69, 95% CI 1.06-2.70). For the children given Meningococcal group C vaccines concomitantly no significantly increased risk was seen in either the bacterial (relative incidence=0.54, 95% CI 0.26-1.13) or viral cases (relative incidence=0.46, 95% CI 0.11-1.93). Our study confirms that the MMR vaccine does not increase the risk of invasive bacterial or viral infection in the 90 days after the vaccination and does not support the hypothesis that there is an induced immune deficiency due to overload from multi-antigen vaccines.

  5. Viral nucleoprotein localization and lesions of Newcastle disease in tissues of indigenous ducks.

    Science.gov (United States)

    Njagi, Lucy Wanjiru; Mbuthia, Paul Gichohi; Nyaga, Phillip Njeru; Bebora, Lilly Caroline; Minga, Uswege M

    2012-04-01

    Localization of Newcastle disease viral nucleoprotein and pathological lesions was evaluated in tissues of 55 indigenous ducks (45 experimentally infected and 10 sentinel ones). In addition, ten Newcastle disease infected chickens were used to ensure that the virus inoculum administered to the ducks produced the disease in chickens, the susceptible hosts. Ducks were killed on day 1, 4, 8 and 14 post-infection. Post-mortem examination was done with six tissues (liver, spleen, lung, caecal tonsils, kidneys and brain) being collected from each bird. The tissues were preserved in 10% neutral formalin for 24 h. They were then transferred to 70% ethanol for histology and immunohistochemical staining. Airsacculitis, necrotic splenic foci, congested intestines, lymphoid depleted caecal tonsils and focal infiltrations by mononuclear cells were the main pathological lesions in infected ducks. Over 28.9% of the infected ducks had Newcastle disease viral nucleoprotein in macrophage-like large mononuclear cells in the caecal tonsils and kidney tubular epithelium. The viral antigens were located in the cytoplasm and nucleolus of the cells. The other organs had no detectable viral antigens. This study shows that the kidneys and caecal tonsils are the likely predilection sites for the virus in ducks. They thus need to be considered as diagnostic indicators for the viral carriage in ducks.

  6. Simian virus 40 DNA replication correlates with expression of a particular subclass of T antigen in a human glial cell line.

    Science.gov (United States)

    Deminie, C A; Norkin, L C

    1990-08-01

    Immunocytochemistry and in situ hybridization were used to identify simian virus 40 (SV40) large T-antigen expression and viral DNA replication in individual cells of infected semipermissive human cell lines. SV40 infection aborts before T-antigen expression in many cells of each of the human cell lines examined. In all but one of the human cell lines, most of the T-antigen-producing cells replicated viral DNA. However, in the A172 line of human glial cells only a small percentage of the T-antigen-expressing cells replicated viral DNA. Since different structural and functional classes of T antigen can be recognized with anti-T monoclonal antibodies, we examined infected A172 cells with a panel of 10 anti-T monoclonal antibodies to determine whether viral DNA replication might correlate with the expression of a particular epitope of T antigen. One anti-T monoclonal antibody, PAb 100, did specifically recognize that subset of A172 cells which replicated SV40 DNA. The percentage of PAb 100-reactive A172 cells was dramatically increased by the DNA synthesis inhibitors hydroxyurea and aphidicolin. Removal of the hydroxyurea was followed by an increase in the percentage of cells replicating viral DNA corresponding to the increased percentage reactive with PAb 100. The pattern of SV40 infection in A172 cells was not altered by infection with viable viral mutants containing lesions in the small t protein, the agnoprotein, or the enhancer region. Finally, in situ hybridization was used to show that the percentage of human cells expressing T antigen was similar to the percentage transcribing early SV40 mRNA. Thus, the block to T-antigen expression in human cells is at a stage prior to transcription of early SV40 mRNA.

  7. Enfermedades virales emergentes y reemergentes

    Directory of Open Access Journals (Sweden)

    Jorge Eliécer Ossa Londoño

    1996-03-01

    Full Text Available Los virus no son una excepción al principio de que toda forma de vida de hoyes el producto de la evolución de información gen ética preexistente. Tradicionalmente se ha reconocido que ta expresión clínica de las enfermedades virales cambia con el tiempo; molecularmente se ha demostrado que esos cambios fenotípicos son el producto de variaciones en el genoma viral. La tasa de cambio
    gen ético y fenotípico no es la misma en todos los agentes virales y ello está determinado, principalmente, por factores intrínsecos del virus, como la naturaleza de su ácido nucleico, y por la longevidad
    y tasa reproductiva del huésped.

  8. Integrin Activation and Viral Infection

    Institute of Scientific and Technical Information of China (English)

    Shan-dian GAO; Jun-zheng DU; Jian-hua ZHOU; Hui-yun CHANG; Qing-ge XIE

    2008-01-01

    Integrins are members of a ubiquitous membrane receptor family which includes 18 different α subunits and 8 β subunits forming more than 20 α/β heterodimers. Integrins play key functions in vascular endothelial cell and tumour cell adhesion, lymphocyte trafficking, tumor growth and viral infection. Current understanding of the molecular basis of integrins as viral receptors has been achieved through many decades of study into the biology of transmembrane glycoproteins and their interactions with several viruses. This review provides a summary of the current knowledge on the molecular bases of interactions between viruses and integrins, which are of potential practical significance. Inhibition of virus-integrin interactions at the points of virus attachment or entry will provide a novel approach for the therapeutic treatment of viral diseases.

  9. Cutaneous manifestations of viral hepatitis.

    Science.gov (United States)

    Akhter, Ahmed; Said, Adnan

    2015-02-01

    There are several extrahepatic cutaneous manifestations associated with hepatitis B and hepatitis C virus infection. Serum sickness and polyarteritis nodosa are predominantly associated with hepatitis B infection, whereas mixed cryoglobulinemia associated vasculitis and porphyria cutanea tarda are more frequently seen in hepatitis C infection. The clinico-pathogenic associations of these skin conditions are not completely defined but appear to involve activation of the host immune system including the complement system. Management of the aforementioned cutaneous manifestations of viral hepatitis is often similar to that done in cases without viral hepatitis, with control of immune activation being a key strategy. In cases associated with hepatitis B and C, control of viral replication with specific antiviral therapy is also important and associated with improvement in most of the associated clinical manifestations.

  10. A Review of Intra- and Extracellular Antigen Delivery Systems for Virus Vaccines of Finfish.

    Science.gov (United States)

    Munang'andu, Hetron Mweemba; Evensen, Øystein

    2015-01-01

    Vaccine efficacy in aquaculture has for a long time depended on evaluating relative percent survival and antibody responses after vaccination. However, current advances in vaccine immunology show that the route in which antigens are delivered into cells is deterministic of the type of adaptive immune response evoked by vaccination. Antigens delivered by the intracellular route induce MHC-I restricted CD8+ responses while antigens presented through the extracellular route activate MHC-II restricted CD4+ responses implying that the route of antigen delivery is a conduit to induction of B- or T-cell immune responses. In finfish, different antigen delivery systems have been explored that include live, DNA, inactivated whole virus, fusion protein, virus-like particles, and subunit vaccines although mechanisms linking these delivery systems to protective immunity have not been studied in detail. Hence, in this review we provide a synopsis of different strategies used to administer viral antigens via the intra- or extracellular compartments. Further, we highlight the differences in immune responses induced by antigens processed by the endogenous route compared to exogenously processed antigens. Overall, we anticipate that the synopsis put together in this review will shed insights into limitations and successes of the current vaccination strategies used in finfish vaccinology.

  11. A Review of Intra- and Extracellular Antigen Delivery Systems for Virus Vaccines of Finfish

    Directory of Open Access Journals (Sweden)

    Hetron Mweemba Munang’andu

    2015-01-01

    Full Text Available Vaccine efficacy in aquaculture has for a long time depended on evaluating relative percent survival and antibody responses after vaccination. However, current advances in vaccine immunology show that the route in which antigens are delivered into cells is deterministic of the type of adaptive immune response evoked by vaccination. Antigens delivered by the intracellular route induce MHC-I restricted CD8+ responses while antigens presented through the extracellular route activate MHC-II restricted CD4+ responses implying that the route of antigen delivery is a conduit to induction of B- or T-cell immune responses. In finfish, different antigen delivery systems have been explored that include live, DNA, inactivated whole virus, fusion protein, virus-like particles, and subunit vaccines although mechanisms linking these delivery systems to protective immunity have not been studied in detail. Hence, in this review we provide a synopsis of different strategies used to administer viral antigens via the intra- or extracellular compartments. Further, we highlight the differences in immune responses induced by antigens processed by the endogenous route compared to exogenously processed antigens. Overall, we anticipate that the synopsis put together in this review will shed insights into limitations and successes of the current vaccination strategies used in finfish vaccinology.

  12. Bystander T cells in human immune responses to dengue antigens

    Directory of Open Access Journals (Sweden)

    Suwannasaen Duangchan

    2010-09-01

    Full Text Available Abstract Background Previous studies of T cell activation in dengue infection have focused on restriction of specific T cell receptors (TCRs and classical MHC molecules. However, bystander T cell activation, which is TCR independent, occurs via cytokines in other viral infections, both in vitro and in vivo, and enables T cells to bypass certain control checkpoints. Moreover, clinical and pathological evidence has pointed to cytokines as the mediators of dengue disease severity. Therefore, we investigated bystander T cell induction by dengue viral antigen. Results Whole blood samples from 55 Thai schoolchildren aged 13-14 years were assayed for in vitro interferon-gamma (IFN-γ induction in response to inactivated dengue serotype 2 antigen (Den2. The contribution of TCR-dependent and independent pathways was tested by treatment with cyclosporin A (CsA, which inhibits TCR-dependent activation of T cells. ELISA results revealed that approximately 72% of IFN-γ production occurred via the TCR-dependent pathway. The major IFN-γ sources were natural killer (NK (mean ± SE = 55.2 ± 3.3, CD4+T (24.5 ± 3.3 and CD8+T cells (17.9 ± 1.5, respectively, as demonstrated by four-color flow cytometry. Interestingly, in addition to these cells, we found CsA-resistant IFN-γ producing T cells (CD4+T = 26.9 ± 3.6% and CD8+T = 20.3 ± 2.1% implying the existence of activated bystander T cells in response to dengue antigen in vitro. These bystander CD4+ and CD8+T cells had similar kinetics to NK cells, appeared after 12 h and were inhibited by anti-IL-12 neutralization indicating cytokine involvement. Conclusions This study described immune cell profiles and highlighted bystander T cell activation in response to dengue viral antigens of healthy people in an endemic area. Further studies on bystander T cell activation in dengue viral infection may reveal the immune mechanisms that protect or enhance pathogenesis of secondary dengue infection.

  13. Going Viral with Fluorescent Proteins.

    Science.gov (United States)

    Costantini, Lindsey M; Snapp, Erik L

    2015-10-01

    Many longstanding questions about dynamics of virus-cell interactions can be answered by combining fluorescence imaging techniques with fluorescent protein (FP) tagging strategies. Successfully creating a FP fusion with a cellular or viral protein of interest first requires selecting the appropriate FP. However, while viral architecture and cellular localization often dictate the suitability of a FP, a FP's chemical and physical properties must also be considered. Here, we discuss the challenges of and offer suggestions for identifying the optimal FPs for studying the cell biology of viruses.

  14. Antigen antibody interactions

    CERN Document Server

    DeLisi, Charles

    1976-01-01

    1. 1 Organization of the Immune System One of the most important survival mechanisms of vertebrates is their ability to recognize and respond to the onslaught of pathogenic microbes to which they are conti- ously exposed. The collection of host cells and molecules involved in this recognition­ 12 response function constitutes its immune system. In man, it comprises about 10 cells 20 (lymphocytes) and 10 molecules (immunoglobulins). Its ontogenic development is c- strained by the requirement that it be capable of responding to an almost limitless variety of molecular configurations on foreign substances, while simultaneously remaining inert to those on self components. It has thus evolved to discriminate, with exquisite precision, between molecular patterns. The foreign substances which induce a response, called antigens, are typically large molecules such as proteins and polysaccharides. The portions of these with which immunoglobulins interact are called epitopes or determinants. A typical protein epitope m...

  15. Engineering antigen-specific T cells from genetically modified human hematopoietic stem cells in immunodeficient mice.

    Directory of Open Access Journals (Sweden)

    Scott G Kitchen

    Full Text Available There is a desperate need for effective therapies to fight chronic viral infections. The immune response is normally fastidious at controlling the majority of viral infections and a therapeutic strategy aimed at reestablishing immune control represents a potentially powerful approach towards treating persistent viral infections. We examined the potential of genetically programming human hematopoietic stem cells to generate mature CD8+ cytotoxic T lymphocytes that express a molecularly cloned, "transgenic" human anti-HIV T cell receptor (TCR. Anti-HIV TCR transduction of human hematopoietic stem cells directed the maturation of a large population of polyfunctional, HIV-specific CD8+ cells capable of recognizing and killing viral antigen-presenting cells. Thus, through this proof-of-concept we propose that genetic engineering of human hematopoietic stem cells will allow the tailoring of effector T cell responses to fight HIV infection or other diseases that are characterized by the loss of immune control.

  16. Variables that influence HIV-1 cerebrospinal fluid viral load in cryptococcal meningitis: a linear regression analysis

    Directory of Open Access Journals (Sweden)

    Cecchini Diego M

    2009-11-01

    Full Text Available Abstract Background The central nervous system is considered a sanctuary site for HIV-1 replication. Variables associated with HIV cerebrospinal fluid (CSF viral load in the context of opportunistic CNS infections are poorly understood. Our objective was to evaluate the relation between: (1 CSF HIV-1 viral load and CSF cytological and biochemical characteristics (leukocyte count, protein concentration, cryptococcal antigen titer; (2 CSF HIV-1 viral load and HIV-1 plasma viral load; and (3 CSF leukocyte count and the peripheral blood CD4+ T lymphocyte count. Methods Our approach was to use a prospective collection and analysis of pre-treatment, paired CSF and plasma samples from antiretroviral-naive HIV-positive patients with cryptococcal meningitis and assisted at the Francisco J Muñiz Hospital, Buenos Aires, Argentina (period: 2004 to 2006. We measured HIV CSF and plasma levels by polymerase chain reaction using the Cobas Amplicor HIV-1 Monitor Test version 1.5 (Roche. Data were processed with Statistix 7.0 software (linear regression analysis. Results Samples from 34 patients were analyzed. CSF leukocyte count showed statistically significant correlation with CSF HIV-1 viral load (r = 0.4, 95% CI = 0.13-0.63, p = 0.01. No correlation was found with the plasma viral load, CSF protein concentration and cryptococcal antigen titer. A positive correlation was found between peripheral blood CD4+ T lymphocyte count and the CSF leukocyte count (r = 0.44, 95% CI = 0.125-0.674, p = 0.0123. Conclusion Our study suggests that CSF leukocyte count influences CSF HIV-1 viral load in patients with meningitis caused by Cryptococcus neoformans.

  17. Mucosal vaccination with heterologous viral vectored vaccine targeting subdominant SIV accessory antigens strongly inhibits early viral replication

    DEFF Research Database (Denmark)

    Xu, Huanbin; Andersson, Anne-Marie; Ragonnaud, Emeline

    2017-01-01

    Conventional HIV T cell vaccine strategies have not been successful in containing acute peak viremia, nor in providing long-term control. We immunized rhesus macaques intramuscularly and rectally using a heterologous adenovirus vectored SIV vaccine regimen encoding normally weakly immunogenic tat...

  18. Antigenic Variation in Bacterial Pathogens.

    Science.gov (United States)

    Palmer, Guy H; Bankhead, Troy; Seifert, H Steven

    2016-02-01

    Antigenic variation is a strategy used by a broad diversity of microbial pathogens to persist within the mammalian host. Whereas viruses make use of a minimal proofreading capacity combined with large amounts of progeny to use random mutation for variant generation, antigenically variant bacteria have evolved mechanisms which use a stable genome, which aids in protecting the fitness of the progeny. Here, three well-characterized and highly antigenically variant bacterial pathogens are discussed: Anaplasma, Borrelia, and Neisseria. These three pathogens display a variety of mechanisms used to create the structural and antigenic variation needed for immune escape and long-term persistence. Intrahost antigenic variation is the focus; however, the role of these immune escape mechanisms at the population level is also presented.

  19. Rapid and sustained CD4(+) T-cell-independent immunity from adenovirus-encoded vaccine antigens

    DEFF Research Database (Denmark)

    Holst, Peter J; Bartholdy, Christina; Buus, Anette Stryhn

    2007-01-01

    Many novel vaccine strategies rely on recombinant viral vectors for antigen delivery, and adenovirus vectors have emerged among the most potent of these. In this report, we have compared the immune response induced through priming with adenovirus vector-encoded full-length viral protein to that e......Many novel vaccine strategies rely on recombinant viral vectors for antigen delivery, and adenovirus vectors have emerged among the most potent of these. In this report, we have compared the immune response induced through priming with adenovirus vector-encoded full-length viral protein...... to that elicited with an adenovirus-encoded minimal epitope covalently linked to beta(2)-microglobulin. We demonstrate that the beta(2)-microglobulin-linked epitope induced an accelerated and augmented CD8(+) T-cell response. Furthermore, the immunity conferred by vaccination with beta(2)-microglobulin...... in the absence of CD4(+) T-cell help were sustained in the long term and able to expand and control a secondary challenge with LCMV. Our results demonstrate that modifications to the antigen used in adenovirus vaccines may be used to improve the induced T-cell response. Such a strategy for CD4(+) T...

  20. Critical Role of Autophagy in the Processing of Adenovirus Capsid-Incorporated Cancer-Specific Antigens.

    Directory of Open Access Journals (Sweden)

    Sarah R Klein

    Full Text Available Adenoviruses are highly immunogenic and are being examined as potential vectors for immunotherapy. Infection by oncolytic adenovirus is followed by massive autophagy in cancer cells. Here, we hypothesize that autophagy regulates the processing of adenoviral proteins for antigen presentation. To test this hypothesis, we first examined the presentation of viral antigens by infected cells using an antibody cocktail of viral capsid proteins. We found that viral antigens were processed by JNK-mediated autophagy, and that autophagy was required for their presentation. Consistent with these results, splenocytes isolated from virus-immunized mice were activated by infected cells in an MHC II-dependent manner. We then hypothesize that this mechanism can be utilized to generate an efficient cancer vaccine. To this end, we constructed an oncolytic virus encompassing an EGFRvIII cancer-specific epitope in the adenoviral fiber. Infection of cancer cells with this fiber-modified adenovirus resulted in recognition of infected cancer cells by a specific anti-EGFRvIII antibody. However, inhibition of autophagy drastically decreased the capability of the specific antibody to detect the cancer-related epitope in infected cells. Our data suggest that combination of adenoviruses with autophagy inducers may enhance the processing and presentation of cancer-specific antigens incorporated into capsid proteins.

  1. Antigenic characterization of avian influenza H9 subtype isolated from desi and zoo birds

    Directory of Open Access Journals (Sweden)

    Farrukh Saleem

    2011-08-01

    Full Text Available Avian influenza is a viral infection which affects mainly the respiratory system of birds. The H9N2 considered as low pathogenic avian influenza (LPAI virus and continuously circulating in poultry flocks causing enormous economic losses to poultry industry of Pakistan. As these viruses have RNA genome and their RNA polymerase enzyme lacks proof reading activity which resulted in spontaneous mutation in surface glycoproteins (HA and NA and reassortment of their genomic segments results in escape from host immune response produced by the vaccine. Efforts made for the isolation and identification of avian influenza virus from live desi and zoo birds of Lahore and performed antigenic characterization. The local vaccines although gives a little bit less titer when we raise the antisera against these vaccines but their antisera have more interaction with the local H9 subtype antigen so it gives better protective immune response. Infected chicken antisera are more reactive as compare to rabbit antisera. This shows that our isolates have highest similarity with the currently circulating viruses. These results guided us to devise a new control strategy against avian influenza viral infections. The antigenic characterization of these avian influenza isolates helped us to see the antigenic differences between the isolates of this study and H9 subtype avian influenza viruses used in vaccines. Therefore, this study clearly suggests that a new local H9 subtype avian influenza virus should be used as vaccinal candidate every year for the effective control of influenza viral infections of poultry.

  2. Antigen-induced regulatory T cells in HBV chronically infected patients.

    Science.gov (United States)

    Barboza, Luisa; Salmen, Siham; Goncalves, Loredana; Colmenares, Melisa; Peterson, Darrell; Montes, Henry; Cartagirone, Raimondo; Gutiérrez, Maria del Carmen; Berrueta, Lisbeth

    2007-11-10

    T cell response against HBV is vigorous in patients with acute hepatitis who clear the virus, whereas it is weak and narrowly focused in patients with chronic disease. We report that following incubation with HBcAg, a population of CD4+FoxP3+ cells expressing phenotypic markers of both natural and induced Tregs, can be antigen-induced from peripheral mononuclear cells. Conversely, naive and naturally immune subjects did not increase CD4+FoxP3+ Tregs following stimulation with HBcAg, supporting the idea that natural Tregs are able to respond specifically to HBV antigen. Furthermore, increased frequencies of antigen-induced CD4+FoxP3+IL-10+ Tregs correlated with viral load, suggesting that antigen-induced Tregs could contribute to an inadequate response against the virus, leading to chronic infection and support the view that specific natural Tregs may be implicated in host immune tolerance during HBV infection.

  3. Effects of sex and generation on hepatitis B viral load in families with hepatocellular carcinoma

    Science.gov (United States)

    Hsieh, Ai-Ru; Fann, Cathy SJ; Yeh, Chau-Ting; Lin, Hung-Chun; Wan, Shy-Yi; Chen, Yi-Cheng; Hsu, Chia-Lin; Tai, Jennifer; Lin, Shi-Ming; Tai, Dar-In

    2017-01-01

    AIM To explore factors associated with persistent hepatitis B virus (HBV) infection in a cohort of hepatocellular carcinoma (HCC)-affected families and then investigate factors that correlate with individual viral load among hepatitis B surface antigen (HBsAg)-positive relatives. METHODS We evaluated non-genetic factors associated with HBV replication in relatives of patients with HCC. Relatives of 355 HCC cases were interviewed using a structured questionnaire. Demographics, relationship to index case, HBsAg status of mothers and index cases were evaluated for association with the HBV persistent infection or viral load by generalized estimating equation analysis. RESULTS Among 729 relatives enrolled, parent generation (P = 0.0076), index generation (P = 0.0044), mothers positive for HBsAg (P = 0.0007), and HBsAg-positive index cases (P = 5.98 × 10-8) were associated with persistent HBV infection. Factors associated with HBV viral load were evaluated among 303 HBsAg-positive relatives. Parent generation (P = 0.0359) and sex (P = 0.0007) were independent factors associated with HBV viral load. The intra-family HBV viral load was evaluated in families clustered with HBsAg-positive siblings. An intra-family trend of similar HBV viral load was found for 27 of 46 (58.7%) families. Male offspring of HBsAg-positive mothers (P = 0.024) and older siblings were associated with high viral load. CONCLUSION Sex and generation play important roles on HBV viral load. Maternal birth age and nutritional changes could be the reasons of viral load difference between generations. PMID:28223732

  4. Ventilator and viral induced inflammation

    NARCIS (Netherlands)

    Hennus, M.P.

    2013-01-01

    This thesis expands current knowledge on ventilator induced lung injury and provides insights on the immunological effects of mechanical ventilation during viral respiratory infections. The experimental studies in the first part of this thesis improve our understanding of how mechanical ventilation

  5. Non-Viral Deoxyribonucleoside Kinases

    DEFF Research Database (Denmark)

    Christiansen, Louise Slot; Munch-Petersen, Birgitte; Knecht, Wolfgang

    2015-01-01

    Deoxyribonucleoside kinases (dNKs) phosphorylate deoxyribonucleosides to their corresponding monophosphate compounds. dNks also phosphorylate deoxyribonucleoside analogues that are used in the treatment of cancer or viral infections. The study of the mammalian dNKs has therefore always been of gr...

  6. Mast cells in viral infections

    Directory of Open Access Journals (Sweden)

    Piotr Witczak

    2012-04-01

    Full Text Available  There are some premises suggesting that mast cells are involved in the mechanisms of anti-virus defense and in viral disease pathomechanisms. Mast cells are particularly numerous at the portals of infections and thus may have immediate and easy contact with the external environment and invading pathogens. These cells express receptors responsible for recognition of virus-derived PAMP molecules, mainly Toll-like receptors (TLR3, TLR7/8 and TLR9, but also RIG-I-like and NOD-like molecules. Furthermore, mast cells generate various mediators, cytokines and chemokines which modulate the intensity of inflammation and regulate the course of innate and adaptive anti-viral immunity. Indirect evidence for the role of mast cells in viral infections is also provided by clinical observations and results of animal studies. Currently, more and more data indicate that mast cells can be infected by some viruses (dengue virus, adenoviruses, hantaviruses, cytomegaloviruses, reoviruses, HIV-1 virus. It is also demonstrated that mast cells can release pre formed mediators as well as synthesize de novo eicosanoids in response to stimulation by viruses. Several data indicate that virus-stimulated mast cells secrete cytokines and chemokines, including interferons as well as chemokines with a key role in NK and Tc lymphocyte influx. Moreover, some information indicates that mast cell stimulation via TLR3, TLR7/8 and TLR9 can affect their adhesion to extracellular matrix proteins and chemotaxis, and influence expression of some membrane molecules. Critical analysis of current data leads to the conclusion that it is not yet possible to make definitive statements about the role of mast cells in innate and acquired defense mechanisms developing in the course of viral infection and/or pathomechanisms of viral diseases.

  7. Autistic disorder and viral infections.

    Science.gov (United States)

    Libbey, Jane E; Sweeten, Thayne L; McMahon, William M; Fujinami, Robert S

    2005-02-01

    Autistic disorder (autism) is a behaviorally defined developmental disorder with a wide range of behaviors. Although the etiology of autism is unknown, data suggest that autism results from multiple etiologies with both genetic and environmental contributions, which may explain the spectrum of behaviors seen in this disorder. One proposed etiology for autism is viral infection very early in development. The mechanism, by which viral infection may lead to autism, be it through direct infection of the central nervous system (CNS), through infection elsewhere in the body acting as a trigger for disease in the CNS, through alteration of the immune response of the mother or offspring, or through a combination of these, is not yet known. Animal models in which early viral infection results in behavioral changes later in life include the influenza virus model in pregnant mice and the Borna disease virus model in newborn Lewis rats. Many studies over the years have presented evidence both for and against the association of autism with various viral infections. The best association to date has been made between congenital rubella and autism; however, members of the herpes virus family may also have a role in autism. Recently, controversy has arisen as to the involvement of measles virus and/or the measles, mumps, rubella (MMR) vaccine in the development of autism. Biological assays lend support to the association between measles virus or MMR and autism whereas epidemiologic studies show no association between MMR and autism. Further research is needed to clarify both the mechanisms whereby viral infection early in development may lead to autism and the possible involvement of the MMR vaccine in the development of autism.

  8. COLONOSCOPY AND CARCINOEMBRYONIC ANTIGEN VARIATIONS

    Directory of Open Access Journals (Sweden)

    Rita G SOUSA

    2014-03-01

    Full Text Available Context Colonoscopy is essential for synchronous and metachronous cancer detection. Carcinoembryonic antigen is a colorectal cancer tumor marker, important as a follow-up tool in patients with previous colorectal cancer. False-positive carcinoembryonic antigen elevation results in multiples exams and in patient anxiety. In literature, there is reference to transient carcinoembryonic antigen increase with colonoscopy. Objective To evaluate the influence of bowel preparation and colonoscopy in carcinoembryonic antigen blood levels. Methods We prospectively studied subjects that underwent routine colonoscopy in our institution. Blood samples were collected (1 before bowel cleaning, (2 before colonoscopy and (3 immediately after colonoscopy. Blood carcinoembryonic antigen levels were determined by “Sandwich” immunoassay. The statistical methods used were the paired t-test and ANOVA. Results Thirty-seven patients (22M/15F were included; age range 28-84 (mean 56 years. Mean carcinoembryonic antigen values were 1.9, 2 and 1.8 for (1, (2 and (3, respectively. An increase in value (2 compared with (1 was observed in 20/37 patients (P = 0.018, mainly in younger patients and in patients requiring more endoluminal interventions. In 29/37 patients, the CEA value decreased from (2 to (3 (P = 1.3x10-7. Conclusions A trend for carcinoembryonic antigen increase after bowel cleaning was observed, especially in younger patients and in patients with more endoluminal interventions, but without clinical meaning.

  9. Equine IgE responses to non-viral vaccine components.

    Science.gov (United States)

    Gershwin, Laurel J; Netherwood, Kristina A; Norris, Meredith Somerville; Behrens, Nicole E; Shao, Matt X

    2012-12-14

    Vaccination of horses is performed annually or semi-annually with multiple viral antigens, either in a combination vaccine or as separate injections. While this practice undoubtedly prevents infection from such diseases as rabies, equine influenza, West Nile virus, and equine herpes virus, the procedure is not without repercussions. Hypersensitivity reactions, including fatal anaphylactic shock, after vaccination, although uncommon, have increased in incidence in recent years. Studies reported herein document the development of IgE antibodies against non-target antigen components of equine viral vaccines. We hypothesize that viral vaccines can induce an IgE response to non-target antigens, which could elicit an adverse response after vaccination with another viral vaccine containing the same component. In one study IgE responses to components of West Nile virus vaccine were evaluated by ELISA before and after vaccination in 30 horses. In a second five-year study 77 horses were similarly tested for IgE antibodies against bovine serum albumin (BSA), a component of most viral vaccines. Mast cell sensitization was evaluated in horses with high, moderate, and negative serum BSA specific IgE using an intradermal skin test with BSA. Over the five-year period high IgE responder horses showed gradually increasing BSA specific serum IgE levels and positive skin test reactivity, yet none had an adverse event. Sera from horses that had developed adverse vaccine reactions were also tested for IgE antibodies. Several of these horses had extremely high levels of BSA-specific IgE. These data suggest that non-essential protein components of vaccines may sensitize horses for future adverse responses to vaccination.

  10. Viral Oncogenes, Noncoding RNAs, and RNA Splicing in Human Tumor Viruses

    Directory of Open Access Journals (Sweden)

    Zhi-Ming Zheng

    2010-01-01

    Full Text Available Viral oncogenes are responsible for oncogenesis resulting from persistent virus infection. Although different human tumor viruses express different viral oncogenes and induce different tumors, their oncoproteins often target similar sets of cellular tumor suppressors or signal pathways to immortalize and/or transform infected cells. Expression of the viral E6 and E7 oncogenes in papillomavirus, E1A and E1B oncogenes in adenovirus, large T and small t antigen in polyomavirus, and Tax oncogene in HTLV-1 are regulated by alternative RNA splicing. However, this regulation is only partially understood. DNA tumor viruses also encode noncoding RNAs, including viral microRNAs, that disturb normal cell functions. Among the determined viral microRNA precursors, EBV encodes 25 from two major clusters (BART and BHRF1, KSHV encodes 12 from a latent region, human polyomavirus MCV produce only one microRNA from the late region antisense to early transcripts, but HPVs appears to produce no viral microRNAs.

  11. Endemic Poultry Viral Diseases 2016 Research Update

    Science.gov (United States)

    Viral infections of the avian gastrointestinal tract negatively impact poultry production; however, determining the complex etiologies of the viral enteric diseases in poultry has been difficult. Project scientists are continuing to investigate the species specificity, molecular phylogenetics, and p...

  12. Exploring the viral world through metagenomics.

    Science.gov (United States)

    Rosario, Karyna; Breitbart, Mya

    2011-10-01

    Viral metagenomics, or shotgun sequencing of purified viral particles, has revolutionized the field of environmental virology by allowing the exploration of viral communities in a variety of sample types throughout the biosphere. The introduction of viral metagenomics has demonstrated that dominant viruses in environmental communities are not well-represented by the cultured viruses in existing sequence databases. Viral metagenomic studies have provided insights into viral ecology by elucidating the genetic potential, community structure, and biogeography of environmental viruses. In addition, viral metagenomics has expanded current knowledge of virus-host interactions by uncovering genes that may allow viruses to manipulate their hosts in unexpected ways. The intrinsic potential for virus discovery through viral metagenomics can help advance a wide array of disciplines including evolutionary biology, pathogen surveillance, and biotechnology.

  13. IFN-induced modulation of histocompatibility antigens on human cells. Background, mechanisms and perspectives

    DEFF Research Database (Denmark)

    Hokland, M; Basse, P; Justesen, J

    1989-01-01

    (MHC) antigens. The latter effects have been characterized as immunomodulatory, whereas the well-known inhibition of growth of malignant cells has been termed anti-proliferative. This review summarizes the current knowledge of the enhancement of MHC products by IFNs. Whereas the basic methodologies...... to the classical anti-viral mechanism. This concept proposes that the MHC-enhancing effect of IFNs is a vital part of the immunological defense against virus infections and an integral part of the anti-viral effects of IFN proteins. Udgivelsesdato: 1988-Nov...

  14. Viral ecology of a shallow eutrophic lake

    NARCIS (Netherlands)

    Tijdens, M.

    2007-01-01

    This thesis aims to give an insight into the ecology of the viral community in a shallow eutrophic lake. To achieve this, the population dynamics, diversity and control of the viral community in Lake Loosdrecht were studied, as well as the impact of the viral community on plankton mortality and comm

  15. Assembly of viral genomes from metagenomes

    NARCIS (Netherlands)

    S.L. Smits (Saskia); R. Bodewes (Rogier); A. Ruiz-Gonzalez (Aritz); V. Baumgärtner (Volkmar); M.P.G. Koopmans D.V.M. (Marion); A.D.M.E. Osterhaus (Albert); A. Schürch (Anita)

    2014-01-01

    textabstractViral infections remain a serious global health issue. Metagenomic approaches are increasingly used in the detection of novel viral pathogens but also to generate complete genomes of uncultivated viruses. In silico identification of complete viral genomes from sequence data would allow r

  16. Production of neutralizing antisera against viral hemorrhagic septicemia (VHS) virus by intravenous injections of rabbits

    DEFF Research Database (Denmark)

    Olesen, Niels Jørgen; Lorenzen, Niels; LaPatra, S.E.

    1999-01-01

    (G) whereas the nonneutralizing sera stained all the viral structural proteins equally well. Our results demonstrate that immunization procedures to produce antisera against VHSV in rabbits determine whether the resultant antibodies will have primarily neutralizing or binding capabilities.......Rabbit antisera against viral hemorrhagic septicemia virus (VHSV) produced by two immunization procedures were compared for neutralization and immunochemical properties against homologous and heterologous strains. The VHSV isolate used as the immunogen was a member of a serogroup not neutralized...... by previously available antisera. The results from this study suggested that frequent intravenous (IV) injections of rabbits with viral antigens were superior to adjuvant-mediated, combined subcutaneous and intraperitoneal (SC/IP) injections for the production of neutralizing antisera. All IV injected rabbits...

  17. Expression and immunogenicity of novel subunit enterovirus 71 VP1 antigens

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Juan [China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Department of Microbiology and Immunology, Nanjing Medical University (China); Wang, Shixia [China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Department of Medicine, University of Massachusetts Medical School (United States); Gan, Weihua [Department of Pediatrics, The Second Affiliated Hospital, Nanjing Medical University (China); Zhang, Wenhong [Department of Infectious Diseases, Huashan Hospital, Fudan University (China); Ju, Liwen [School of Public Health, Fudan University (China); Huang, Zuhu [Department of Infectious Diseases, The First Affiliated Hospital, Nanjing Medical University (China); China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Lu, Shan, E-mail: shan.lu@umassmed.edu [Department of Infectious Diseases, The First Affiliated Hospital, Nanjing Medical University (China); China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Department of Medicine, University of Massachusetts Medical School (United States)

    2012-04-20

    Highlights: Black-Right-Pointing-Pointer EV71 is a major emerging infectious disease in many Asian countries. Black-Right-Pointing-Pointer Inactivated EV71 vaccines are in clinical studies but their safety and efficacy are unknown. Black-Right-Pointing-Pointer Developing subunit based EV71 vaccines is significant and novel antigen design is needed. Black-Right-Pointing-Pointer DNA immunization is an efficient tool to test the immunogenicity of VP1 based EV71 vaccines. Black-Right-Pointing-Pointer Multiple VP1 antigens are developed showing immunogenic potential. -- Abstract: Hand, foot, and mouth disease (HFMD) is a common viral illness in young children. HFMD is caused by viruses belonging to the enterovirus genus of the picornavirus family. Recently, enterovirus 71 (EV71) has emerged as a virulent agent for HFMD with severe clinical outcomes. In the current report, we conducted a pilot antigen engineering study to optimize the expression and immunogenicity of subunit VP1 antigen for the design of EV71 vaccines. DNA immunization was adopted as a simple technical approach to test different designs of VP1 antigens without the need to express VP1 protein in vitro first. Our studies indicated that the expression and immunogenicity of VP1 protein can be improved with alternated VP1 antigen designs. Data presented in the current report revealed novel pathways to optimize the design of VP1 antigen-based EV71 vaccines.

  18. Diminished Memory T-Cell Expansion Due to Delayed Kinetics of Antigen Expression by Lentivectors.

    Directory of Open Access Journals (Sweden)

    Karina Furmanov

    Full Text Available Memory CD8(+ T lymphocytes play a central role in protective immunity. In attempt to increase the frequencies of memory CD8(+ T cells, repeated immunizations with viral vectors are regularly explored. Lentivectors have emerged as a powerful vaccine modality with relatively low pre-existing and anti-vector immunity, thus, thought to be ideal for boosting memory T cells. Nevertheless, we found that lentivectors elicited diminished secondary T-cell responses that did not exceed those obtained by priming. This was not due to the presence of anti-vector immunity, as limited secondary responses were also observed following heterologous prime-boost immunizations. By dissecting the mechanisms involved in this process, we demonstrate that lentivectors trigger exceptionally slow kinetics of antigen expression, while optimal activation of lentivector-induced T cells relays on durable expression of the antigen. These qualities hamper secondary responses, since lentivector-encoded antigen is rapidly cleared by primary cytotoxic T cells that limit its presentation by dendritic cells. Indeed, blocking antigen clearance by cytotoxic T cells via FTY720 treatment, fully restored antigen presentation. Taken together, while low antigen expression is expected during secondary immunization with any vaccine vector, our results reveal that the intrinsic delayed expression kinetics of lentiviral-encoded antigen, further dampens secondary CD8(+ T-cell expansion.

  19. [Laboratory diagnosis of HIV infection, viral tropism and resistance to antiretrovirals].

    Science.gov (United States)

    García, Federico; Álvarez, Marta; Bernal, Carmen; Chueca, Natalia; Guillot, Vicente

    2011-04-01

    The accurate diagnosis of HIV infection demands that to consider a positive result, at least three assays with different antigenic base should be used, one of them, Western-Blot being mandatory for confirmation. Fourth generation ELISAs shorten the window phase to 13-15 days, as they now include p24 antigen detection. Proviral DNA or Viral RNA detection by molecular methods have proved useful for addressing complex situations in which serology was inconclusive. Viral load (HIV-RNA) is routinely used to follow-up HIV infected patients and is used for treatment initiation decisions. It is also used to monitor viral failure. When this happens, resistance tests are needed to guide treatment changes. Resistance is also used to assess the transmission of drug resistance to newly diagnosed patients. Finally, before using an anti-CCR5 drug, viral tropism needs to be determined. This can be done using genotypic tests, widely available in many HIV labs, or phenotypic tests, only available at certain sites.

  20. Inactivation and stability of viral diagnostic reagents treated by gamma radiation.

    Science.gov (United States)

    White, L A; Freeman, C Y; Hall, H E; Forrester, B D

    1990-10-01

    The objective of this study was to apply the pertinent findings from gamma inactivation of virus infectivity to the production of high quality diagnostic reagents. A Gammacell 220 (Atomic Energy of Canada, Ltd., Ottawa, Canada) was used to subject 38 viruses grown in either susceptible tissue cultures or embryonated chicken eggs to various doses of gamma radiation from a cobalt-60 source. The radiation required to reduce viral infectivity was 0.42 to 3.7 megarads (Mrad). The effect of gamma treatment on the antigenic reactivity of reagents for the complement fixation (CF), hemagglutination (HA) and neuraminadase assays was determined. Influenza antigens inactivated with 1.7 Mrad displayed comparable potency, sensitivity, specificity and stability to those inactivated by standard procedures with beta-propiolactone (BPL). Significant inactivation of influenza N1 and B neuraminidase occurred with greater than 2.4 Mrad radiation at temperatures above 4 degrees C. All 38 viruses were inactivated, and CF or HA antigens were prepared successfully. Antigenic potency remained stable with all antigens for 3 years and with 83% after 5 years storage. Influenza HA antigens evaluated after 9 years of storage demonstrated 86% stability. Gamma radiation is safer than chemical inactivation procedures and is reliable and effective replacement for BPL in preparing diagnostic reagents.

  1. Viral diseases and human evolution

    Directory of Open Access Journals (Sweden)

    Leal Élcio de Souza

    2000-01-01

    Full Text Available The interaction of man with viral agents was possibly a key factor shaping human evolution, culture and civilization from its outset. Evidence of the effect of disease, since the early stages of human speciation, through pre-historical times to the present suggest that the types of viruses associated with man changed in time. As human populations progressed technologically, they grew in numbers and density. As a consequence different viruses found suitable conditions to thrive and establish long-lasting associations with man. Although not all viral agents cause disease and some may in fact be considered beneficial, the present situation of overpopulation, poverty and ecological inbalance may have devastating effets on human progress. Recently emerged diseases causing massive pandemics (eg., HIV-1 and HCV, dengue, etc. are becoming formidable challenges, which may have a direct impact on the fate of our species.

  2. [Recent acquisitions on viral hepatitis].

    Science.gov (United States)

    Resti, M; Tucci, F; Vierucci, A

    1990-01-01

    In the last years the research on viral hepatitis let to better understand the biological, molecular, immunological and epidemiologic characteristics of the viruses that are responsible for hepatitis. The first studied virus was hepatitis B virus (HBv). The scientific attention is still, today, focused on that virus since new markers of infectivity and biological importance in early diagnosis and in disease evolution have been found. The most important result in the last years in the field of viral hepatitis has been, however, the identification of agents responsible for Non-A-Non-B hepatitis. Its epidemiology and clinical importance are discussed in the present paper. Virus C is the most important parenteral agent of NANB hepatitis. Its epidemiology in at risk populations and its role in post-transfusional and cryptogenetic hepatitis are here discussed. The research of new markers of HCV infection is today considered a main goal since the role of the only marker now available is still under discussion.

  3. Virally encoded 7TM receptors

    DEFF Research Database (Denmark)

    Rosenkilde, M M; Waldhoer, M; Lüttichau, H R

    2001-01-01

    A number of herpes- and poxviruses encode 7TM G-protein coupled receptors most of which clearly are derived from their host chemokine system as well as induce high expression of certain 7TM receptors in the infected cells. The receptors appear to be exploited by the virus for either immune evasion...... in various parts of the viral life cyclus. Most of the receptors encoded by human pathogenic virus are still orphan receptors, i.e. the endogenous ligand is unknown. In the few cases where it has been possible to characterize these receptors pharmacologically, they have been found to bind a broad spectrum...... expression of this single gene in certain lymphocyte cell lineages leads to the development of lesions which are remarkably similar to Kaposi's sarcoma, a human herpesvirus 8 associated disease. Thus, this and other virally encoded 7TM receptors appear to be attractive future drug targets....

  4. RHEUMATIC MANIFESTATIONS IN VIRAL HEPATITIS

    Directory of Open Access Journals (Sweden)

    L P Anan'eva

    2008-01-01

    Full Text Available Autoimmune reactions are of primary importance in the development of extrahepatic manifestations of viral hepatitis, among which there are rheumatic symptoms and syndromes. The incidence of clinically significant extrahepatic manifestations is shown to be relatively low, but they may be in the foreground in the clinical picture of the disease and are noted for severity. It is concluded that due to the high prevalence of hepatitis and the systemic pattern of their chronic forms, patients with extrahepatic manifestations of viral hepatitis may be encountered in the practice of a therapist and a rheumatologist. The onset of the infection caused by hepatitis viruses may be accompanied by articular lesion therefore the rheumatologist may be the first physician such a patient may resort to.

  5. RHEUMATIC MANIFESTATIONS IN VIRAL HEPATITIS

    Directory of Open Access Journals (Sweden)

    L P Anan'eva

    2008-12-01

    Full Text Available Autoimmune reactions are of primary importance in the development of extrahepatic manifestations of viral hepatitis, among which there are rheumatic symptoms and syndromes. The incidence of clinically significant extrahepatic manifestations is shown to be relatively low, but they may be in the foreground in the clinical picture of the disease and are noted for severity. It is concluded that due to the high prevalence of hepatitis and the systemic pattern of their chronic forms, patients with extrahepatic manifestations of viral hepatitis may be encountered in the practice of a therapist and a rheumatologist. The onset of the infection caused by hepatitis viruses may be accompanied by articular lesion therefore the rheumatologist may be the first physician such a patient may resort to.

  6. Oncogenic cancer/testis antigens

    DEFF Research Database (Denmark)

    Gjerstorff, Morten F; Andersen, Mads H; Ditzel, Henrik J

    2015-01-01

    Recent developments have set the stage for immunotherapy as a supplement to conventional cancer treatment. Consequently, a significant effort is required to further improve efficacy and specificity, particularly the identification of optimal therapeutic targets for clinical testing. Cancer....../testis antigens are immunogenic, highly cancer-specific, and frequently expressed in various types of cancer, which make them promising candidate targets for cancer immunotherapy, including cancer vaccination and adoptive T-cell transfer with chimeric T-cell receptors. Our current understanding of tumor...... immunology and immune escape suggests that targeting oncogenic antigens may be beneficial, meaning that identification of cancer/testis antigens with oncogenic properties is of high priority. Recent work from our lab and others provide evidence that many cancer/testis antigens, in fact, have oncogenic...

  7. Treatment of acute viral bronchiolitis.

    Science.gov (United States)

    Eber, Ernst

    2011-01-01

    Acute viral bronchiolitis represents the most common lower respiratory tract infection in infants and young children and is associated with substantial morbidity and mortality. Respiratory syncytial virus is the most frequently identified virus, but many other viruses may also cause acute bronchiolitis. There is no common definition of acute viral bronchiolitis used internationally, and this may explain part of the confusion in the literature. Most children with bronchiolitis have a self limiting mild disease and can be safely managed at home with careful attention to feeding and respiratory status. Criteria for referral and admission vary between hospitals as do clinical practice in the management of acute viral bronchiolitis, and there is confusion and lack of evidence over the best treatment for this condition. Supportive care, including administration of oxygen and fluids, is the cornerstone of current treatment. The majority of infants and children with bronchiolitis do not require specific measures. Bronchodilators should not be routinely used in the management of acute viral bronchiolitis, but may be effective in some patients. Most of the commonly used management modalities have not been shown to have a clear beneficial effect on the course of the disease. For example, inhaled and systemic corticosteroids, leukotriene receptor antagonists, immunoglobulins and monoclonal antibodies, antibiotics, antiviral therapy, and chest physiotherapy should not be used routinely in the management of bronchiolitis. The potential effect of hypertonic saline on the course of the acute disease is promising, but further studies are required. In critically ill children with bronchiolitis, today there is little justification for the use of surfactant and heliox. Nasal continuous positive airway pressure may be beneficial in children with severe bronchiolitis but a large trial is needed to determine its value. Finally, very little is known on the effect of the various

  8. Viral diseases and human evolution

    OpenAIRE

    2000-01-01

    The interaction of man with viral agents was possibly a key factor shaping human evolution, culture and civilization from its outset. Evidence of the effect of disease, since the early stages of human speciation, through pre-historical times to the present suggest that the types of viruses associated with man changed in time. As human populations progressed technologically, they grew in numbers and density. As a consequence different viruses found suitable conditions to thrive and establish l...

  9. CXC Chemokine Ligand 10 Controls Viral Infection in the Central Nervous System: Evidence for a Role in Innate Immune Response through Recruitment and Activation of Natural Killer Cells

    OpenAIRE

    Trifilo, Matthew J.; Montalto-Morrison, Cynthia; Stiles, Linda N.; Hurst, Kelley R.; Hardison, Jenny L.; Manning, Jerry E.; Masters, Paul S.; Lane, Thomas E.

    2004-01-01

    How chemokines shape the immune response to viral infection of the central nervous system (CNS) has largely been considered within the context of recruitment and activation of antigen-specific lymphocytes. However, chemokines are expressed early following viral infection, suggesting an important role in coordinating innate immune responses. Herein, we evaluated the contributions of CXC chemokine ligand 10 (CXCL10) in promoting innate defense mechanisms following coronavirus infection of the C...

  10. PENGAMATAN SERO—VIROLOGI BEBERAPA JENIS ANTIGEN VIRUS PADA SERUM TALIPUSAT BAYI DI RS. CIPTO MANGUNKUSUMO, JAKARTA

    Directory of Open Access Journals (Sweden)

    Djoko Yuwono

    2012-09-01

    Full Text Available Perinatal infection due to viral agents from mother to neonate is still a major cause of viral transmis­sion in developing countries. Several type of viruses which are known to be transmitted vertieally or perinatally from mother to neonates are: Hepatitis B virus, Herpes simplex, Rubella and Cytomegalovi­rus. In attempt to estimate the real problem of viral diseases which are vertically or perinatally transmis­sible among infants, a survey on sero-virology of several type viral antigens among neonates who were borned in Dr. Cipto Mangunkusumo hospital, was carried out. A total of 227 blood samples of umbillical cord were examined for the presence of their viral anti­gens such as: Hepatitis B surface antigen (HBsAg, Herpes simplex type 1 and type 2, and anti-rubella IgM as an indicator of early infection due to rubella virus in the fetus. The detection of antigens and anti-rubella IgM in the serum.were done by ELISA methode using reagents which are commercially available. The result of the study indicated that there was a possibility of perinatal infection due to related viruses, i.e.: 2.2%; 1.9% and 14.3% due to HBsAg; Herpes simplex type 1 and type 2 respectivelly, however none of the serum indicated seropositive IgM against rubella virus: infection.

  11. Recycling Endosomes and Viral Infection

    Directory of Open Access Journals (Sweden)

    Sílvia Vale-Costa

    2016-03-01

    Full Text Available Many viruses exploit specific arms of the endomembrane system. The unique composition of each arm prompts the development of remarkably specific interactions between viruses and sub-organelles. This review focuses on the viral–host interactions occurring on the endocytic recycling compartment (ERC, and mediated by its regulatory Ras-related in brain (Rab GTPase Rab11. This protein regulates trafficking from the ERC and the trans-Golgi network to the plasma membrane. Such transport comprises intricate networks of proteins/lipids operating sequentially from the membrane of origin up to the cell surface. Rab11 is also emerging as a critical factor in an increasing number of infections by major animal viruses, including pathogens that provoke human disease. Understanding the interplay between the ERC and viruses is a milestone in human health. Rab11 has been associated with several steps of the viral lifecycles by unclear processes that use sophisticated diversified host machinery. For this reason, we first explore the state-of-the-art on processes regulating membrane composition and trafficking. Subsequently, this review outlines viral interactions with the ERC, highlighting current knowledge on viral-host binding partners. Finally, using examples from the few mechanistic studies available we emphasize how ERC functions are adjusted during infection to remodel cytoskeleton dynamics, innate immunity and membrane composition.

  12. Pediatric Asthma and Viral Infection.

    Science.gov (United States)

    Garcia-Garcia, M Luz; Calvo Rey, Cristina; Del Rosal Rabes, Teresa

    2016-05-01

    Respiratory viral infections, particularly respiratory syncytial virus (RSV) and rhinovirus, are the most importance risk factors for the onset of wheezing in infants and small children. Bronchiolitis is the most common acute respiratory infection in children under 1year of age, and the most common cause of hospitalization in this age group. RSV accounts for approximately 70% of all these cases, followed by rhinovirus, adenovirus, metapneumovirus and bocavirus. The association between bronchiolitis caused by RSV and the development of recurrent wheezing and/or asthma was first described more than 40years ago, but it is still unclear whether bronchiolitis causes chronic respiratory symptoms, or if it is a marker for children with a genetic predisposition for developing asthma in the medium or long term. In any case, sufficient evidence is available to corroborate the existence of this association, which is particularly strong when the causative agent of bronchiolitis is rhinovirus. The pathogenic role of respiratory viruses as triggers for exacerbations in asthmatic patients has not been fully characterized. However, it is clear that respiratory viruses, and in particular rhinovirus, are the most common causes of exacerbation in children, and some type of respiratory virus has been identified in over 90% of children hospitalized for an episode of wheezing. Changes in the immune response to viral infections in genetically predisposed individuals are very likely to be the main factors involved in the association between viral infection and asthma.

  13. Extracting viral RNAs from plant protoplasts.

    Science.gov (United States)

    Fabian, Marc R; Andrew White, K

    2007-08-01

    The analysis of viral RNA is a fundamental aspect of plant RNA virus research. Studies that focus on viral RNAs often involve virus infections of plant protoplasts (see UNITS 16D.1-16D.4). Protoplast offer the advantage of simultaneous initiation of infections, which allows for superior temporal and quantitative analyses of viral RNAs. The efficient isolation of intact viral RNA is key to any such investigations. This unit describes two basic protocols for extracting viral RNAs from plant protoplasts. An approach for preparing double-stranded viral RNA from total RNA pools is also provided. The viral RNA prepared by using these techniques can be used for further analyses such as primer extension, reverse transcription-PCR, and northern blotting.

  14. Viral-templated Palladium Nanocatalysts

    Science.gov (United States)

    Yang, Cuixian

    Despite recent progress on nanocatalysis, there exist several critical challenges in simple and readily controllable nanocatalyst synthesis including the unpredictable particle growth, deactivation of catalytic activity, cumbersome catalyst recovery and lack of in-situ reaction monitoring. In this dissertation, two novel approaches are presented for the fabrication of viral-templated palladium (Pd) nanocatalysts, and their catalytic activities for dichromate reduction reaction and Suzuki Coupling reaction were thoroughly studied. In the first approach, viral template based bottom-up assembly is employed for the Pd nanocatalyst synthesis in a chip-based format. Specifically, genetically displayed cysteine residues on each coat protein of Tobacco Mosaic Virus (TMV) templates provide precisely spaced thiol functionalities for readily controllable surface assembly and enhanced formation of catalytically active Pd nanoparticles. Catalysts with the chip-based format allow for simple separation and in-situ monitoring of the reaction extent. Thorough examination of synthesis-structure-activity relationship of Pd nanoparticles formed on surface-assembled viral templates shows that Pd nanoparticle size, catalyst loading density and catalytic activity of viral-templated Pd nanocatalysts can be readily controlled simply by tuning the synthesis conditions. The viral-templated Pd nanocatalysts with optimized synthesis conditions are shown to have higher catalytic activity per unit Pd mass than the commercial Pd/C catalysts. Furthermore, tunable and selective surface assembly of TMV biotemplates is exploited to control the loading density and location of Pd nanocatalysts on solid substrates via preferential electroless deposition. In addition, the catalytic activities of surface-assembled TMV-templated Pd nanocatalysts were also investigated for the ligand-free Suzuki Coupling reaction under mild reaction conditions. The chip-based format enables simple catalyst separation and

  15. Endogenous type C viral gene expression in cultures of fetal diploid baboon cells treated with 5'-bromodeoxyuridine

    Energy Technology Data Exchange (ETDEWEB)

    Lavelle, G.; Kennel, S.J.; Foote, L.J.

    1981-04-30

    Cultures of fetal diploid baboon fibroblasts treated with 5-bromodeoxyuridine synthesized protein antigenically related to baboon endogenous type C viral gag gene product, p28. Radioimmunoassays detected p28 antigenic specificities indistinguishable from those of purified virus. However, viral RNA-dependent DNA polymerase was not detected in culture fluids, and infectious virus was rarely recovered by cocultivation with susceptible heterologous cells. Extracellular particles containing p28 were not readily detected, further indicating that viral gag gene-coded proteins were synthesized independently of whole virus. Normal cultures of the same baboon cells exhibited endogenous expression of a glycoprotein antigenically related to BEV gp70, suggesting differential regulation of the endogenous gag and env gene-coded products. Baboon cell cultures exogenously infected with BEV produced extracellular particles having viral p28 and gp70 as measured by radioimmunoassays of culture fluids. Since induced cultures have about 10% positive cells versus close to 100% for infected culture, the amount of p28 per producing cell was about the same in both cell populations.

  16. Enhancement of Mucosal Immunogenicity of Viral Vectored Vaccines by the NKT Cell Agonist Alpha-Galactosylceramide as Adjuvant

    Directory of Open Access Journals (Sweden)

    Shailbala Singh

    2014-10-01

    Full Text Available Gene-based vaccination strategies, specifically viral vectors encoding vaccine immunogens are effective at priming strong immune responses. Mucosal routes offer practical advantages for vaccination by ease of needle-free administration, and immunogen delivery at readily accessible oral/nasal sites to efficiently induce immunity at distant gut and genital tissues. However, since mucosal tissues are inherently tolerant for induction of immune responses, incorporation of adjuvants for optimal mucosal vaccination strategies is important. We report here the effectiveness of alpha-galactosylceramide (α-GalCer, a synthetic glycolipid agonist of natural killer T (NKT cells, as an adjuvant for enhancing immunogenicity of vaccine antigens delivered using viral vectors by mucosal routes in murine and nonhuman primate models. Significant improvement in adaptive immune responses in systemic and mucosal tissues was observed by including α-GalCer adjuvant for intranasal immunization of mice with vesicular stomatitis virus vector encoding the model antigen ovalbumin and adenoviral vectors expressing HIV env and Gag antigens. Activation of NKT cells in systemic and mucosal tissues along with significant increases in adaptive immune responses were observed in rhesus macaques immunized by intranasal and sublingual routes with protein or adenovirus vectored antigens when combined with α-GalCer adjuvant. These results support the utility of α-GalCer adjuvant for enhancing immunogenicity of mucosal vaccines delivered using viral vectors.

  17. [Blood transfusion and viral diseases. Recent acquisitions concerning viral hepatitis viruses, cytomegaloviruses and Epstein-Barr virus].

    Science.gov (United States)

    Spanò, C

    1979-02-11

    In recent years, an increasingly clear picture has been formed of the virus-induced syndromes that may follow a blood transfusion or the use of blood derivatives. Up to about 10 years ago, post-infusion infection was predominantly due to serum hepatitis. Blumberg's discovery of HBsAg (formerly known as Australia antigen) has made it possible to check and prevent viral hepatitis, type B, and to recognise such distinct forms as the mononucleosis-like syndrome caused by cytomegalic virus, infectious mononucleosis caused by EB virus, and so-called non A/non B hepatitis. A brief account of recent advances with respect to the biological features of the viruses responsible for type A and type B hepatitis, CMV and EB virus, and their behaviour in man is followed by an examination of the transfusional aspects, the methods used in their study, and the difficulties involved. The soundness of existing methods and the need for their standardisation are discussed.

  18. Encefalitis virales en la infancia

    Directory of Open Access Journals (Sweden)

    Monserrat Téllez de Meneses

    2013-09-01

    Full Text Available La encefalitis viral es una enfermedad grave que implica el compromiso inflamatorio del parénquima cerebral. Las infecciones virales del SNC ocurren con frecuencia como complicación de infecciones virales sistémicas. Más de 100 virus están implicados como agentes causales, entre los cuales el virus Herpes simplex tipo I, es el agente causal más frecuente de encefalitis no epidémica en todos los grupos poblacionales del mundo; es el responsable de los casos más graves en todas las edades. Muchos de los virus para los cuales existe vacunas también pueden causar encefalitis como: sarampión, paperas, polio, rabia, rubéola, varicela. El virus produce una inflamación del tejido cerebral, la cual puede evolucionar a una destrucción de neuronas, provocar hemorragia y daño cerebral, dando lugar a encefalitis graves, como la encefalitis necrotizante o hemorrágica, con mucho peor pronóstico, produciendo secuelas graves, incluso la muerte. El cuadro clínico, incluye la presencia de cefalea, fiebre y alteración de la conciencia, de rápida progresión. El pronóstico de las encefalitis víricas es variable, algunos casos son leves, con recuperación completa, sin embargo existen casos graves que pueden ocasionar secuelas importantes a nivel cerebral. Es fundamental realizar un diagnóstico lo antes posible, a través de pruebas de laboratorio (bioquímica, PCR, cultivos y de neuroimagen (TAC, RM y ante todo, la instauración de un tratamiento precoz para evitar la evolución del proceso y sus posibles complicaciones. El pronóstico empeora si se retrasa la instauración del tratamiento.

  19. Evaluation of Viral Meningoencephalitis Cases

    Directory of Open Access Journals (Sweden)

    Handan Ilhan

    2012-08-01

    Full Text Available AIM: To evaluate retrospectively adult cases of viral encephalitis. METHOD: Fifteen patients described viral encephalitis hospitalized between the years 2006-2011 follow-up and treatment at the infectious diseases clinic were analyzed retrospectively. RESULTS: Most of the patients (%60 had applied in the spring. Fever (87%, confusion (73%, neck stiffness (73%, headache (73%, nausea-vomiting (33%, loss of consciousness (33%, amnesia (33%, agitation (20%, convulsion (%20, focal neurological signs (13%, Brudzinski-sign (13% were most frequently encountered findings. Electroencephalography test was applied to 13 of 14 patients, and pathological findings compatible with encephalitis have been found. Radiological imaging methods such as CT and MRI were performed in 9 of the 14 patients, and findings consistent with encephalitis were reported. All of initial cerebrospinal fluid (CSF samples were abnormal. The domination of the first examples was lymphocytes in 14 patients; only one patient had an increase in neutrophilic cells have been found. CSF protein level was high in nine patients, and low glucose level was detected in two patients. Herpes simplex virus polymerized chain reaction (PCR analyze was performed to fourteen patients CSF. Only two of them (14% were found positive. One of the patients sample selectively examined was found to be Parvovirus B19 (+, the other patient urine sample Jacobs-creutzfeld virus PCR was found to be positively. Empiric acyclovir therapy was given to all patients. Neuropsychiatric squeal developed at the one patient. CONCLUSION: The cases in the forefront of change in mental status viral meningoencephalitis should be considered and empirical treatment with acyclovir should be started. [TAF Prev Med Bull 2012; 11(4.000: 447-452

  20. Semen from boars infected with porcine reproductive and respiratory syndrome virus (PRRSV) contains antibodies against structural as well as nonstructural viral proteins

    DEFF Research Database (Denmark)

    Oleksiewicz, M. B.; Bøtner, Anette; Normann, Preben

    2001-01-01

    antigen, we were able to separately and specifically assay antibody responses against structural and nonstructural viral proteins. Antibodies against structural as well as nonstructural viral proteins were consistently found in the semen of all boars, beginning from 1-4 weeks postinfection....... This is the first report documenting the presence of anti-PRRSV antibodies in boar semen, Seminal antiviral IgA was also detected, and we observed a correlation between seminal IgA responses against nonstructural viral proteins, and the duration of PRRSV RNA excretion in semen. The implications of these findings...

  1. Mast cells in viral infections

    OpenAIRE

    Piotr Witczak; Ewa Brzezińska-Błaszczyk

    2012-01-01

     There are some premises suggesting that mast cells are involved in the mechanisms of anti-virus defense and in viral disease pathomechanisms. Mast cells are particularly numerous at the portals of infections and thus may have immediate and easy contact with the external environment and invading pathogens. These cells express receptors responsible for recognition of virus-derived PAMP molecules, mainly Toll-like receptors (TLR3, TLR7/8 and TLR9), but also RIG-I-like and NOD-like molecules. Fu...

  2. Authentic counterfeit in viral marketing

    OpenAIRE

    2016-01-01

    This master thesis deals with authentic fake, a phenomenon present in viral marketing. After a brief introduction into the issue and clarification of terms, the study aims to find out whether a seemingly authentic video recording of a catchy incident helps a marketing campaign to succeed, that is to say to achieve high sharing figures amongst internet users. In a theoretical part, the thesis elaborates information from technical books, publications and internet sources dealing with authentici...

  3. Viral diseases of marine invertebrates

    Science.gov (United States)

    Johnson, P. T.

    1984-03-01

    Approximately 40 viruses are known from marine sponges; turbellarian and monogenetic flatworms; cephalopod, bivalve, and gastropod mollusks; nereid polychaetes; and isopod and decapod crustaceans. Most of the viruses can be tentatively assigned to the Herpesviridae, Baculoviridae, Iridoviridae, Adenoviridae, Papovaviridae, Reoviridae, “Birnaviridae”, Bunyaviridae, Rhabdoviridae, and Picornaviridae. Viruslike particles found in oysters might be representatives of the Togaviridae and Retroviridae. Enveloped single-stranded RNA viruses from crustaceans have developmental and morphological characteristics intermediate between families, and some show evidence of relationships to the Paramyxoviridae as well as the Bunyaviridae or Rhabdoviridae. Certain small viruses of shrimp cannot be assigned, even tentatively, to a particular family. Some viruses cause disease in wild and captive hosts, others are associated with disease states but may not be primary instigators, and many occur in apparently normal animals. The frequency of viral disease in natural populations of marine invertebrates is unknown. Several viruses that cause disease in captive animals, with or without experimental intervention, have also been found in diseased wild hosts, including herpeslike viruses of crabs and oysters, iridovirus of octopus, and reolike and bunyalike viruses of crabs. Iridolike viruses have been implicated in massive mortalities of cultured oysters. Baculoviruses, and IHHN virus, which is of uncertain affinities, cause economically damaging diseases in cultured penaeid shrimp. Double or multiple viral infection is common in crabs. For example, a reolike virus and associated rhabdolike virus act synergistically to cause paralytic and fatal disease in Callinectes sapidus. Information on host range, most susceptible stage, and viral latency is available only for viruses of shrimp. One baculovirus attacks five species of New World penaeid shrimp. IHHN virus infects three species of

  4. T Cell Memory in the Context of Persistent Herpes Viral Infections

    Directory of Open Access Journals (Sweden)

    Nicole Torti

    2012-07-01

    Full Text Available The generation of a functional memory T cell pool upon primary encounter with an infectious pathogen is, in combination with humoral immunity, an essential process to confer protective immunity against reencounters with the same pathogen. A prerequisite for the generation and maintenance of long-lived memory T cells is the clearance of antigen after infection, which is fulfilled upon resolution of acute viral infections. Memory T cells play also a fundamental role during persistent viral infections by contributing to relative control and immuosurveillance of active replication or viral reactivation, respectively. However, the dynamics, the phenotype, the mechanisms of maintenance and the functionality of memory T cells which develop upon acute/resolved infection as opposed to chronic/latent infection differ substantially. In this review we summarize current knowledge about memory CD8 T cell responses elicited during α-, β-, and γ-herpes viral infections with major emphasis on the induction, maintenance and function of virus-specific memory CD8 T cells during viral latency and we discuss how the peculiar features of these memory CD8 T cell responses are related to the biology of these persistently infecting viruses.

  5. One step ahead of the game: viral immunomodulatory molecules.

    Science.gov (United States)

    Spriggs, M K

    1996-01-01

    For decades cell biologists have relied on viruses to facilitate the study of complex cellular function. More recently, the tragedy of the AIDS epidemic has focused considerable human and financial resources on both virology and immunology, resulting in the generation of new information relating these disciplines. As the miracle of the mammalian immune system unfolds in the laboratory, the elegance of the mechanisms used by co-evolving viruses to circumvent detection and destruction by the host becomes inescapably obvious. Although many observation of virus-induced phenomena that likely contribute to the virus's escape of immune surveillance are still empirical, many other such phenomena have now been defined at the molecular level and confirmed in in vivo models. Immune modulators encoded within viral genomes include proteins that regulate antigen presentation, function as cytokines or cytokine antagonists, inhibit apoptosis, and interrupt the complement cascade. The identification of such gene products and the elucidation of their function have substantially strengthened our understanding of specific virus-host interactions and, unexpectedly, have contributed to the recognition of potent synergy between viruses, which can result in an unpredictable exacerbation of disease in co-infected individuals. Because many viral immune modulators clearly have host counterparts, viruses provide a valuable method for studying normal immune mechanisms. It is conceivable that an improved understanding of virus-encoded immunomodulators will enhance our ability to design reagents for use in therapeutic intervention in disease and in vaccine development.

  6. Origin and function of circulating plasmablasts during acute viral infections

    Directory of Open Access Journals (Sweden)

    Katja eFink

    2012-04-01

    Full Text Available Activated B cells proliferate and differentiate into antibody-producing cells, long-lived plasma cells and memory B cells after immunization or infection. Repeated encounter of the same antigen triggers the rapid re-activation of pre-existing specific memory B cells, which then possibly enter new germinal center reactions and differentiate into short-lived plasmablasts or remain in the system as memory B cells. Short-lived plasmablasts appear in the circulation transiently and the frequency of these cells can be remarkably high. The specificities and affinities of single plasmablasts have been reported for several viral infections, so far most extensively for influenza and HIV. In general, the immunoglobulin variable regions of plasmablasts are highly mutated and diverse, showing that plasmablasts are derived from memory B cells, yet it is unclear which memory B cell subsets are activated and whether activated memory B cells adapt or mature before differentiation. This review summarizes what is known about the phenotype and the origin of human plasmablasts in the context of viral infections and whether these cells can be predictors of long-lived immunity.

  7. Typing of viral hemorrhagic septicemia virus by monoclonal antibodies

    DEFF Research Database (Denmark)

    Ito, Takafumi; Kurita, Jun; Sano, Motohiko

    2012-01-01

    Seven mAbs with specific reaction patterns against each of the four genotypes and eight subtypes of viral hemorrhagic septicemia virus (VHSV) were produced, aiming to establish an immunoassay for typing VHSV isolates according to their genotype. Among the mAbs, VHS-1.24 reacted with all genotypes...... between all four genotypes and between five of eight subtypes of VHSV by testing isolates in immunoassay using a panel of nine mAbs. By Western blotting and transfection of cell cultures, it was shown that mAb VHS-1.24 recognized an epitope on the viral phosphoprotein (P), whilst all others recognized...... antigenic determinants on the nucleoprotein (N). From amino acid alignments of the various genotypes and subtypes of VHSV isolates, it was possible to determine the epitope specificity of mAb VHS-1.24 to be aa 32–34 in the P-protein; the specificities of mAbs VHS-3.80, VHS-7.57 and VHS-3.75 were found...

  8. Viral piracy: HIV-1 targets dendritic cells for transmission.

    Science.gov (United States)

    Lekkerkerker, Annemarie N; van Kooyk, Yvette; Geijtenbeek, Teunis B H

    2006-04-01

    Dendritic cells (DCs), the professional antigen presenting cells, are critical for host immunity by inducing specific immune responses against a broad variety of pathogens. Remarkably the human immunodeficiency virus-1 (HIV-1) subverts DC function leading to spread of the virus. At an early phase of HIV-1 transmission, DCs capture HIV-1 at mucosal surfaces and transmit the virus to T cells in secondary lymphoid tissues. Capture of the virus on DCs takes place via C-type lectins of which the dendritic cell-specific intercellular adhesion molecule-3 (ICAM-3) grabbing nonintegrin (DC-SIGN) is the best studied. DC-SIGN-captured HIV-1 particles accumulate in CD81(+) multivesicular bodies (MVBs) in DCs and are subsequently transmitted to CD4+ T cells resulting in infection of T cells. The viral cell-to-cell transmission takes place at the DC-T cell interface termed the infectious synapse. Recent studies demonstrate that direct infection of DCs contributes to the transmission to T cells at a later phase. Moreover, the infected DCs may function as cellular reservoirs for HIV-1. This review discusses the different processes that govern viral piracy of DCs by HIV-1, emphasizing the intracellular routing of the virus from capture on the cell surface to egress in the infectious synapse.

  9. Recombinant protein-based viral disease diagnostics in veterinary medicine.

    Science.gov (United States)

    Balamurugan, Vinayagamurthy; Venkatesan, Gnanavel; Sen, Arnab; Annamalai, Lakshmanan; Bhanuprakash, Veerakyathappa; Singh, Raj Kumar

    2010-09-01

    Identification of pathogens or antibody response to pathogens in human and animals modulates the treatment strategies for naive population and subsequent infections. Diseases can be controlled and even eradicated based on the epidemiology and effective prophylaxis, which often depends on development of efficient diagnostics. In addition, combating newly emerging diseases in human as well as animal healthcare is challenging and is dependent on developing safe and efficient diagnostics. Detection of antibodies directed against specific antigens has been the method of choice for documenting prior infection. Other than zoonosis, development of inexpensive vaccines and diagnostics is a unique problem in animal healthcare. The advent of recombinant DNA technology and its application in the biotechnology industry has revolutionized animal healthcare. The use of recombinant DNA technology in animal disease diagnosis has improved the rapidity, specificity and sensitivity of various diagnostic assays. This is because of the absence of host cellular proteins in the recombinant derived antigen preparations that dramatically decrease the rate of false-positive reactions. Various recombinant products are used for disease diagnosis in veterinary medicine and this article discusses recombinant-based viral disease diagnostics currently used for detection of pathogens in livestock and poultry.

  10. Innate immune response to viral infection.

    Science.gov (United States)

    Koyama, Shohei; Ishii, Ken J; Coban, Cevayir; Akira, Shizuo

    2008-09-01

    In viral infections the host innate immune system is meant to act as a first line defense to prevent viral invasion or replication before more specific protection by the adaptive immune system is generated. In the innate immune response, pattern recognition receptors (PRRs) are engaged to detect specific viral components such as viral RNA or DNA or viral intermediate products and to induce type I interferons (IFNs) and other pro-inflammatory cytokines in the infected cells and other immune cells. Recently these innate immune receptors and their unique downstream pathways have been identified. Here, we summarize their roles in the innate immune response to virus infection, discrimination between self and viral nucleic acids and inhibition by virulent factors and provide some recent advances in the coordination between innate and adaptive immune activation.

  11. Non-cytolytic antigen clearance in DNA-vaccinated mice with electropotation

    Institute of Scientific and Technical Information of China (English)

    Jin-liang PENG; Yong-gang ZHAO; Jun-hua MAI; Wen-ka PANG; Wei GUO; Guang-ming CHEN; Guo-yu MO; Gui-rong RAO; Yu-hong XU

    2007-01-01

    Aim: To explore the potential of electroporation (EP)-mediated hepatitis B virus (HBV) DNA vaccination for the treatment of chronic HBV infection. Methods: BALB/c mice were vaccinated with HBV DNA vaccine encoding for the HBV preS2-S antigen, combined with or without EP. HBV surface antigen expression plasmid was administered into mice liver via a hydrodynamic injection to mimic HBV infection. The clearance of antigen in the serum and liver was detected by ELISA assay and immunohistochemical staining. The histopathology of the liver tissues was examined by HE staining and serum alanine aminotransferase assay.Results: The immunogenicity ofHBV DNA vaccine encoding for the HBV preS2-S antigen can be improved by EP-mediated vaccine delivery. The elicited immune responses can indeed reduce the expression of HBV surface antigen (HBsAg) in hepatocytes of the mouse model that was transfected to express HBsAg using the hydrodynamic injection method. The antigen clearance process did not cause significant toxicity to liver tissue, suggesting a non-cytolytic mechanism. Conclusion: The EP-aided DNA vaccination may have potential in mediating viral clearance in chronic hepatitis B patients.

  12. The antigenic property of the H5N1 avian influenza viruses isolated in central China

    Directory of Open Access Journals (Sweden)

    Zou Wei

    2012-08-01

    Full Text Available Abstract Background Three influenza pandemics outbroke in the last century accompanied the viral antigen shift and drift, resulting in the change of antigenic property and the low cross protective ability of the existed antibody to the newly emerged pandemic virus, and eventually the death of millions of people. The antigenic characterizations of the viruses isolated in central China in 2004 and 2006–2007 were investigated in the present study. Results Hemagglutinin inhibition assay and neutralization assay displayed differential antigenic characteristics of the viruses isolated in central China in two periods (2004 and 2006–2007. HA genes of the viruses mainly located in two branches in phylogeny analysis. 53 mutations of the deduced amino acids of the HA genes were divided into 4 patterns. Mutations in pattern 2 and 3 showed the main difference between viruses isolated in 2004 and 2006–2007. Meanwhile, most amino acids in pattern 2 and 3 located in the globular head of the HA protein, and some of the mutations evenly distributed at the epitope sites. Conclusions The study demonstrated that a major antigenic drift had occurred in the viruses isolated in central China. And monitoring the antigenic property should be the priority in preventing the potential pandemic of H5N1 avian influenza virus.

  13. Commercialization of veterinary viral vaccines.

    Science.gov (United States)

    Flore, P H

    2004-12-01

    If vaccines are to reliably prevent disease, they must be developed, produced and quality-controlled according to very strict regulations and procedures. Veterinary viral vaccine registrations are governed by different rules in different countries, but these rules all emphasize that the quality of the raw materials--the cells, eggs, animals or plants that are used in production--need to be carefully controlled. The veterinary vaccine business is also very cost-conscious. Emphasis over the last 5-10 years has therefore been to develop culture systems that minimize labor and sterility problems and thus provide for reliable and cost-effective production. Implementing these often more complex systems in a production environment takes considerable effort, first in scale-up trials and further down the line in convincing production personnel to change their familiar system for something new and possibly untried. To complete scale-up trials successfully, it is absolutely necessary to understand the biochemistry of the cells and the influence of the virus on the cells under scale-up and later production conditions. Once a viral product can be produced on a large scale, it is imperative that the quality of the end-product is controlled in an intelligent way. One needs to know whether the end-product performs in the animal as was intended during its conception in the research and development department. The development of the appropriate tests to demonstrate this plays an important role in the successful development of a vaccine.

  14. Population Dynamics of Viral Inactivation

    Science.gov (United States)

    Freeman, Krista; Li, Dong; Behrens, Manja; Streletzky, Kiril; Olsson, Ulf; Evilevitch, Alex

    We have investigated the population dynamics of viral inactivation in vitrousing time-resolved cryo electron microscopy combined with light and X-ray scattering techniques. Using bacteriophage λ as a model system for pressurized double-stranded DNA viruses, we found that virions incubated with their cell receptor eject their genome in a stochastic triggering process. The triggering of DNA ejection occurs in a non synchronized manner after the receptor addition, resulting in an exponential decay of the number of genome-filled viruses with time. We have explored the characteristic time constant of this triggering process at different temperatures, salt conditions, and packaged genome lengths. Furthermore, using the temperature dependence we determined an activation energy for DNA ejections. The dependences of the time constant and activation energy on internal DNA pressure, affected by salt conditions and encapsidated genome length, suggest that the triggering process is directly dependent on the conformational state of the encapsidated DNA. The results of this work provide insight into how the in vivo kinetics of the spread of viral infection are influenced by intra- and extra cellular environmental conditions. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1252522.

  15. Sequencing Needs for Viral Diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, S N; Lam, M; Mulakken, N J; Torres, C L; Smith, J R; Slezak, T

    2004-01-26

    We built a system to guide decisions regarding the amount of genomic sequencing required to develop diagnostic DNA signatures, which are short sequences that are sufficient to uniquely identify a viral species. We used our existing DNA diagnostic signature prediction pipeline, which selects regions of a target species genome that are conserved among strains of the target (for reliability, to prevent false negatives) and unique relative to other species (for specificity, to avoid false positives). We performed simulations, based on existing sequence data, to assess the number of genome sequences of a target species and of close phylogenetic relatives (''near neighbors'') that are required to predict diagnostic signature regions that are conserved among strains of the target species and unique relative to other bacterial and viral species. For DNA viruses such as variola (smallpox), three target genomes provide sufficient guidance for selecting species-wide signatures. Three near neighbor genomes are critical for species specificity. In contrast, most RNA viruses require four target genomes and no near neighbor genomes, since lack of conservation among strains is more limiting than uniqueness. SARS and Ebola Zaire are exceptional, as additional target genomes currently do not improve predictions, but near neighbor sequences are urgently needed. Our results also indicate that double stranded DNA viruses are more conserved among strains than are RNA viruses, since in most cases there was at least one conserved signature candidate for the DNA viruses and zero conserved signature candidates for the RNA viruses.

  16. Consumers’ attitude towards viral marketing in Pakistan

    OpenAIRE

    Kiani Irshad ZERNIGAH; Kamran SOHAIL

    2012-01-01

    The rapid advancement of technology has opened many costeffective avenues for marketers to promote their products. One of the emerging techniques of products promotion through the use of technology is viral marketing that is becoming a popular direct marketing tool for marketers across the world. Therefore, marketers should understand factors that result in increased acceptance of viral marketing by consumers. The present research was conducted to investigate consumers’ attitude towards viral...

  17. Pediatric knowledge about acute viral hepatitis

    OpenAIRE

    Franca,Rita; Silva,Luciana; Melo, Maria Clotildes; Cavalcante,Suzy; Lima, Bruno; Rocha, Anita; Gomes, Cristiana; Franca, Mônica

    2004-01-01

    p.227-235 Knowledge about hepatotropic viruses is crucial for pediatricians because of the high prevalence of viral hepatitis during childhood. The multiplicity of hepatotropic viruses, the spectrum of acute and chronic infections, and the sequels of viral hepatitis result in a need for physicians to better understand the clinical and epidemiological context of patients with viral hepatitis, as well as the importance of prevention measures for hepatitis. A descriptive cross-sectional study...

  18. Sponging of Cellular Proteins by Viral RNAs

    OpenAIRE

    Charley, Phillida A.; Wilusz, Jeffrey

    2014-01-01

    Viral RNAs accumulate to high levels during infection and interact with a variety of cellular factors including miRNAs and RNA-binding proteins. Although many of these interactions exist to directly modulate replication, translation and decay of viral transcripts, evidence is emerging that abundant viral RNAs may in certain cases serve as a sponge to sequester host non coding RNAs and proteins. By effectively reducing the ability of cellular RNA binding proteins to regulate host cell gene exp...

  19. Viral Advertising on Facebook in Vietnam

    OpenAIRE

    Tran, Phuong

    2014-01-01

    The purpose of this thesis is to explore which factors affect the effectiveness of viral advertising on Facebook in Vietnam. The quantitative research method is applied in this research and the sample is Vietnamese Facebook users. After the data analysis stage using SPSS, it became clear that weak ties, perceptual affinity and emotions have an impact on the effectiveness of viral advertising. The results provide a pratical implication of how to make an Ad which can go viral on Facebook. Moreo...

  20. Exploring Text Virality in Social Networks

    CERN Document Server

    Guerini, Marco; Ozbal, Gozde

    2012-01-01

    This paper aims to shed some light on the concept of virality - especially in social networks - and to provide new insights on its structure. We argue that: (a) virality is a phenomenon strictly connected to the nature of the content being spread, rather than to the influencers who spread it, (b) virality is a phenomenon with many facets, i.e. under this generic term several different effects of persuasive communication are comprised and they only partially overlap. To give ground to our claims, we provide initial experiments in a machine learning framework to show how various aspects of virality can be independently predicted according to content features.

  1. Hepatitis A through E (Viral Hepatitis)

    Science.gov (United States)

    ... Liver Disease & NASH Definition & Facts Symptoms & Causes Diagnosis Treatment Eating, Diet, & Nutrition Clinical Trials Biliary Atresia Cirrhosis Hemochromatosis Hepatitis A through E (Viral Hepatitis) Hepatitis ...

  2. Cross-reactive anti-viral T cells increase prior to an episode of viral reactivation post human lung transplantation.

    Directory of Open Access Journals (Sweden)

    Thi H O Nguyen

    Full Text Available Human Cytomegalovirus (CMV reactivation continues to influence lung transplant outcomes. Cross-reactivity of anti-viral memory T cells against donor human leukocyte antigens (HLA may be a contributing factor. We identified cross-reactive HLA-A*02:01-restricted CMV-specific cytotoxic T lymphocytes (CTL co-recognizing the NLVPMVATV (NLV epitope and HLA-B27. NLV-specific CD8+ T cells were expanded for 13 days from 14 HLA-A*02:01/CMV seropositive healthy donors and 11 lung transplant recipients (LTR then assessed for the production of IFN-γ and CD107a expression in response to 19 cell lines expressing either single HLA-A or -B class I molecules. In one healthy individual, we observed functional and proliferative cross-reactivity in response to B*27:05 alloantigen, representing approximately 5% of the NLV-specific CTL population. Similar patterns were also observed in one LTR receiving a B27 allograft, revealing that the cross-reactive NLV-specific CTL gradually increased (days 13-193 post-transplant before a CMV reactivation event (day 270 and reduced to basal levels following viral clearance (day 909. Lung function remained stable with no acute rejection episodes being reported up to 3 years post-transplant. Individualized immunological monitoring of cross-reactive anti-viral T cells will provide further insights into their effects on the allograft and an opportunity to predict sub-clinical CMV reactivation events and immunopathological complications.

  3. High numbers of IL-2-producing CD8+ T cells during viral infection: correlation with stable memory development

    DEFF Research Database (Denmark)

    Kristensen, Nanna Ny; Christensen, Jan Pravsgaard; Thomsen, Allan Randrup

    2002-01-01

    Using infections with lymphocytic choriomeningitis virus (LCMV) and vesicular stomatitis virus in mice as model systems, we have investigated the ability of antigen-primed CD8+ T cells generated in the context of viral infections to produce IL-2. Our results indicate that acute immunizing infection...... normally leads to generation of high numbers of IL-2-producing antigen-specific CD8+ T cells. By costaining for IL-2 and IFN-gamma intracellularly, we found that IL-2-producing cells predominantly constitute a subset of cells also producing IFN-gamma. Comparison of the kinetics of generation revealed...

  4. STUDY OF PERSISTENT VIRAL INFECTION IN AN ANIMALMODEL OF VIRAL MYOCARDITIS BY PCR

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective To study the role of persistent viral infection in the mechanism of viral myocarditis. Methods A mice model of CVB3m viral myocarditis was made and the viral RNA in mice myocardium and whole blood sample was tested by using polymerase chain reaction ( PCR ) technique. The pathological changes in mice myocardium were determined. Results On day 3, the viral gene in whole blood and myocardium was found, which partly became negative on day 8, but the change of myocardial pathology became obvious. Although the blood specimens were tested negatively on day 12, the viral gene in mice myocardium remained positive within 120d. Conclusion This study indicates that persistent viral infection plays a role in the pathogenesis of viral myocarditis.

  5. Viral diseases of northern ungulates

    Directory of Open Access Journals (Sweden)

    K. Frölich

    2000-03-01

    Full Text Available This paper describes viral diseases reported in northern ungulates and those that are a potential threat to these species. The following diseases are discussed: bovine viral diarrhoea/mucosal disease (BVD/MD, alphaherpesvirus infections, malignant catarrhal fever (MCF, poxvirus infections, parainfluenza type 3 virus infection, Alvsborg disease, foot-and-mouth disease, epizootic haemorrhage disease of deer and bluetongue disease, rabies, respiratory syncytial virus infection, adenovirus infection, hog-cholera, Aujeszky's disease and equine herpesvirus infections. There are no significant differences in antibody prevalence to BVDV among deer in habitats with high, intermediate and low density of cattle. In addition, sequence analysis from the BVDV isolated from roe deer (Capreolus capreolus showed that this strain was unique within BVDV group I. Distinct BVDV strains might circulate in free-ranging roe deer populations in Germany and virus transmission may be independent of domestic livestock. Similar results have been obtained in a serological survey of alpha-herpesviruses in deer in Germany. Malignant catarrhal fever was studied in fallow deer (Cervus dama in Germany: the seroprevalence and positive PCR results detected in sheep originating from the same area as the antibody-positive deer might indicate that sheep are the main reservoir animals. Contagious ecthyma (CE is a common disease in domestic sheep and goats caused by the orf virus. CE has been diagnosed in Rocky Mountain bighorn sheep (Ovis canadensis, mountain goats (Oreamnos americanus, Dall sheep (Ovis dalli, chamois (Rupkapra rupi-capra, muskox {Ovibos moschatus and reindeer (Rangifer tarandus. Most parainfluenza type 3 virus infections are mild or clinically undetectable. Serological surveys in wildlife have been successfully conducted in many species. In 1985, a new disease was identified in Swedish moose (Alces alces, designated as Alvsborg disease. This wasting syndrome probably

  6. Immunohistological demonstration of serum proteins and structural and viral antigens in paraffin sections of nervous tissues.

    Science.gov (United States)

    Budka, H

    1983-01-01

    A brief outline is given of applications of immunohistological techniques to the study of normal and diseased nervous tissue. Protease treatment of paraffin sections usually enhances sensitivity and reliability both of IF and PAP techniques. Sensitivity of immunohistological examination of paraffin sections is comparable to that of virus detection by normal virological techniques in animal rabies and slightly superior to EM search for virions in SSPE and PML. Immunostaining for MBP appears to be the most sensitive method for myelin, especially for demonstration of very thin myelin sheaths, which are important in studies of myelogenesis and cortical myeloarchitecture. Prolonged fixation in formalin clearly diminishes or abolishes immunoreactivity. Compacted myelin stains less well for MBP than preparative myelin artefacts and the surface of myelinated fibers. GFAP production is enhanced when glioma cells invade surrounding mesenchymal structures. The chance finding of GFAP-like immunoreactivity in a cancer metastasis casts doubt on the astroglial specificity of GFAP.

  7. Influenza neuraminidase as a vaccine antigen

    Science.gov (United States)

    The neuraminidase protein of influenza viruses is a surface glycoprotein that has enzymatic activity to remove sialic acid, the viral receptor, from both viral and host proteins. The removal of sialic acid from viral proteins plays a key role in the release of the virus from the cell by preventing ...

  8. Reduced interleukin-4 receptor α expression on CD8+ T cells correlates with higher quality anti-viral immunity.

    Directory of Open Access Journals (Sweden)

    Danushka K Wijesundara

    Full Text Available With the hope of understanding how interleukin (IL-4 and IL-13 modulated quality of anti-viral CD8(+ T cells, we evaluated the expression of receptors for these cytokines following a range of viral infections (e.g. pox viruses and influenza virus. Results clearly indicated that unlike other IL-4/IL-13 receptor subunits, IL-4 receptor α (IL-4Rα was significantly down-regulated on anti-viral CD8(+ T cells in a cognate antigen dependent manner. The infection of gene knockout mice and wild-type (WT mice with vaccinia virus (VV or VV expressing IL-4 confirmed that IL-4, IL-13 and signal transducer and activator of transcription 6 (STAT6 were required to increase IL-4Rα expression on CD8(+ T cells, but not interferon (IFN-γ. STAT6 dependent elevation of IL-4Rα expression on CD8(+ T cells was a feature of poor quality anti-viral CD8(+ T cell immunity as measured by the production of IFN-γ and tumor necrosis factor α (TNF-α in response to VV antigen stimulation in vitro. We propose that down-regulation of IL-4Rα, but not the other IL-4/IL-13 receptor subunits, is a mechanism by which CD8(+ T cells reduce responsiveness to IL-4 and IL-13. This can improve the quality of anti-viral CD8(+ T cell immunity. Our findings have important implications in understanding anti-viral CD8(+ T cell immunity and designing effective vaccines against chronic viral infections.

  9. Viral Ancestors of Antiviral Systems

    Directory of Open Access Journals (Sweden)

    Luis P. Villarreal

    2011-10-01

    Full Text Available All life must survive their corresponding viruses. Thus antiviral systems are essential in all living organisms. Remnants of virus derived information are also found in all life forms but have historically been considered mostly as junk DNA. However, such virus derived information can strongly affect host susceptibility to viruses. In this review, I evaluate the role viruses have had in the origin and evolution of host antiviral systems. From Archaea through bacteria and from simple to complex eukaryotes I trace the viral components that became essential elements of antiviral immunity. I conclude with a reexamination of the ‘Big Bang’ theory for the emergence of the adaptive immune system in vertebrates by horizontal transfer and note how viruses could have and did provide crucial and coordinated features.

  10. Viral bronchiolitis for the clinician.

    Science.gov (United States)

    Fitzgerald, Dominic A

    2011-04-01

    Viral bronchiolitis is common, and about 98-99% of infants are managed in the home. Because about 95% of infants < 2 years old are infected with respiratory syncytial virus, however, bronchiolitis is the commonest reason for admission to hospital in the first 6 months of life. It is usually a self-limiting condition lasting around a week in previously well children. About 1% of infants are admitted to hospital, and about 10% of hospitalised infants will require admission to the intensive care unit. Respiratory syncytial virus is isolated from about 70% of infants hospitalised with bronchiolitis. The emphasis of hospital treatment is to ensure adequate hydration and oxygenation. Other than supplemental oxygen, little in the way of pharmacological treatment has been demonstrated to alter the course of the illness or the risk of wheezing in the months following bronchiolitis.

  11. Viral ancestors of antiviral systems.

    Science.gov (United States)

    Villarreal, Luis P

    2011-10-01

    All life must survive their corresponding viruses. Thus antiviral systems are essential in all living organisms. Remnants of virus derived information are also found in all life forms but have historically been considered mostly as junk DNA. However, such virus derived information can strongly affect host susceptibility to viruses. In this review, I evaluate the role viruses have had in the origin and evolution of host antiviral systems. From Archaea through bacteria and from simple to complex eukaryotes I trace the viral components that became essential elements of antiviral immunity. I conclude with a reexamination of the 'Big Bang' theory for the emergence of the adaptive immune system in vertebrates by horizontal transfer and note how viruses could have and did provide crucial and coordinated features.

  12. Multiple lineages of antigenically and genetically diverse influenza A virus co-circulate in the United States swine population.

    Science.gov (United States)

    Webby, R J; Rossow, K; Erickson, G; Sims, Y; Webster, R

    2004-07-01

    Before the isolation of H3N2 viruses in 1998, swine influenza in the United States was an endemic disease caused exclusively by classical-swine H1N1 viruses. In this study we determined the antigenic and phylogenetic composition of a selection of currently circulating strains and revealed that, in contrast to the situation pre-1998, the swine population in the United States is now a dynamic viral reservoir containing multiple viral lineages. H3N2 viruses still circulate and representatives of each of two previously identified phylogenetic groups were isolated. H1N1 and H1N2 viruses were also identified. In addition to the genotypic diversity present, there was also considerable antigenic diversity seen. At least three antigenic profiles of H1 viruses were noted and all of the recent H3N2 viruses reacted poorly, if at all, to the index A/swine/Texas/4199-2/98 H3N2 antiserum in hemagglutination inhibition assays. The influenza reservoir in the United States swine population has thus gone from a stable single viral lineage to one where genetically and antigenically heterogenic viruses co-circulate. The growing complexity of influenza at this animal-human interface and the presence of viruses with a seemingly high affinity for reassortment makes the United States swine population an increasingly important reservoir of viruses with human pandemic potential.

  13. Induction of CD8+ T-cell responses against subunit antigens by the novel cationic liposomal CAF09 adjuvant

    DEFF Research Database (Denmark)

    Korsholm, Karen Smith; Hansen, Jon; Karlsen, Kasper

    2014-01-01

    Vaccines inducing cytotoxic T-cell responses are required to achieve protection against cancers and intracellular infections such as HIV and Hepatitis C virus. Induction of CD8+ T cell responses in animal models can be achieved by the use of viral vectors or DNA vaccines but so far without much...... clinical success. Here we describe the novel CD8+ T-cell inducing adjuvant, cationic adjuvant formulation (CAF) 09, consisting of dimethyldioctadecylammonium (DDA)-liposomes stabilized with monomycoloyl glycerol (MMG)-1 and combined with the TLR3 ligand, Poly(I:C). Different antigens from tuberculosis (TB......10.3, H56), HIV (Gag p24), HPV (E7) and the model antigen ovalbumin were formulated with CAF09 and administering these vaccines to mice resulted in a high frequency of antigen-specific CD8+ T cells. CAF09 was superior in its ability to induce antigen-specific CD8+ T cells as compared to other...

  14. Antigen-Experienced T cells Limit the Priming of Naïve T cells During Infection with Leishmania major1

    Science.gov (United States)

    Gray, Peter M.; Reiner, Steven L.; Smith, Deborah F.; Kaye, Paul M.; Scott, Phillip

    2009-01-01

    One mechanism to control immune responses following infection is to rapidly down regulate antigen presentation, which has been observed in acute viral and bacterial infections. Here we describe experiments designed to address whether antigen presentation is decreased after an initial response to Leishmania major. Naïve α-β-Leishmania-specific (ABLE) T cell receptor transgenic T cells were adoptively transferred into mice at various times after L. major infection to determine the duration of presentation of parasite-derived antigens. ABLE T cells responded vigorously at the initiation of infection, but the ability to prime these cells quickly diminished, independent of IL-10, regulatory T cells or antigen load. However, antigen-experienced clonal and polyclonal T cell populations could respond, indicating that the diminution in naïve ABLE cell responses was not due to lack of antigen presentation. Since naïve T cell priming could be restored by removal of the endogenous T cell population, or adoptive transfer of antigen pulsed dendritic cells, it appears that T cells that have previously encountered antigen during infection compete with naïve antigen-specific T cells. These results suggest that during L. major infection antigen-experienced T cells, rather than naïve T cells, may be primarily responsible for sustaining the immune response. PMID:16818747

  15. Concepts and applications for influenza antigenic cartography

    Science.gov (United States)

    Cai, Zhipeng; Zhang, Tong; Wan, Xiu-Feng

    2011-01-01

    Influenza antigenic cartography projects influenza antigens into a two or three dimensional map based on immunological datasets, such as hemagglutination inhibition and microneutralization assays. A robust antigenic cartography can facilitate influenza vaccine strain selection since the antigenic map can simplify data interpretation through intuitive antigenic map. However, antigenic cartography construction is not trivial due to the challenging features embedded in the immunological data, such as data incompleteness, high noises, and low reactors. To overcome these challenges, we developed a computational method, temporal Matrix Completion-Multidimensional Scaling (MC-MDS), by adapting the low rank MC concept from the movie recommendation system in Netflix and the MDS method from geographic cartography construction. The application on H3N2 and 2009 pandemic H1N1 influenza A viruses demonstrates that temporal MC-MDS is effective and efficient in constructing influenza antigenic cartography. The web sever is available at http://sysbio.cvm.msstate.edu/AntigenMap. PMID:21761589

  16. Losartan and enalapril decrease viral absorption and interleukin 1 beta production by macrophages in an experimental dengue virus infection.

    Science.gov (United States)

    Hernández-Fonseca, Juan Pablo; Durán, Anyelo; Valero, Nereida; Mosquera, Jesús

    2015-11-01

    The role of angiotensin II (Ang II) in dengue virus infection remains unknown. The aim of this study was to determine the effect of losartan, an antagonist of the angiotensin II type 1 receptor (AT1 receptor), and enalapril, an inhibitor of angiotensin I-converting enzyme (ACE), on viral antigen expression and IL-1β production in peritoneal macrophages infected with dengue virus type 2. Mice treated with losartan or enalapril and untreated controls were infected intraperitoneally with the virus, and macrophages were analyzed. Infection resulted in increased IL-1β production and a high percentage of cells expressing viral antigen, and this was decreased by treatment with anti-Ang II drugs, suggesting a role for Ang II in dengue virus infection.

  17. Emerging Viral Diseases of Tomato Crops

    NARCIS (Netherlands)

    Hanssen, I.M.; Lapidot, M.; Thomma, B.P.H.J.

    2010-01-01

    Viral diseases are an important limiting factor in many crop production systems. Because antiviral products are not available, control strategies rely on genetic resistance or hygienic measures to prevent viral diseases, or on eradication of diseased crops to control such diseases. Increasing intern

  18. Viral Quasispecies Assembly via Maximal Clique Enumeration

    NARCIS (Netherlands)

    Toepfer, A.; Marschall, T.; Bull, R.A.; Luciani, F.; Schoenhuth, A.; Beerenwinkel, N.

    2014-01-01

    Virus populations can display high genetic diversity within individual hosts. The intra-host collection of viral haplotypes, called viral quasispecies, is an important determinant of virulence, pathogenesis, and treatment outcome. We present HaploClique, a computational approach to reconstruct the s

  19. Molecular biology of bovine viral diarrhea virus

    Science.gov (United States)

    Bovine viral diarrhea viruses (BVDV) are arguably the most important viral pathogen of ruminants worldwide and can cause severe economic loss. Clinical symptoms of the disease caused by BVDV range from subclinical to severe acute hemorrhagic syndrome, with the severity of disease being strain depend...

  20. A Molecular-Level Account of the Antigenic Hantaviral Surface

    Directory of Open Access Journals (Sweden)

    Sai Li

    2016-05-01

    Full Text Available Hantaviruses, a geographically diverse group of zoonotic pathogens, initiate cell infection through the concerted action of Gn and Gc viral surface glycoproteins. Here, we describe the high-resolution crystal structure of the antigenic ectodomain of Gn from Puumala hantavirus (PUUV, a causative agent of hemorrhagic fever with renal syndrome. Fitting of PUUV Gn into an electron cryomicroscopy reconstruction of intact Gn-Gc spike complexes from the closely related but non-pathogenic Tula hantavirus localized Gn tetramers to the membrane-distal surface of the virion. The accuracy of the fitting was corroborated by epitope mapping and genetic analysis of available PUUV sequences. Interestingly, Gn exhibits greater non-synonymous sequence diversity than the less accessible Gc, supporting a role of the host humoral immune response in exerting selective pressure on the virus surface. The fold of PUUV Gn is likely to be widely conserved across hantaviruses.

  1. Origins and challenges of viral dark matter.

    Science.gov (United States)

    Krishnamurthy, Siddharth R; Wang, David

    2017-02-09

    The accurate classification of viral dark matter - metagenomic sequences that originate from viruses but do not align to any reference virus sequences - is one of the major obstacles in comprehensively defining the virome. Depending on the sample, viral dark matter can make up from anywhere between 40 and 90% of sequences. This review focuses on the specific nature of dark matter as it relates to viral sequences. We identify three factors that contribute to the existence of viral dark matter: the divergence and length of virus sequences, the limitations of alignment based classification, and limited representation of viruses in reference sequence databases. We then discuss current methods that have been developed to at least partially circumvent these limitations and thereby reduce the extent of viral dark matter.

  2. Ethical Considerations in Research Participation Virality.

    Science.gov (United States)

    Ellis-Barton, Carol

    2016-07-01

    This article seeks to commence and encourage discussion around the upcoming ethical challenges of virality in network structures. When the call for participation in a research project on lupus in Ireland went from an advertisement in a newsletter to a meme (unit of transmissible information) on a closed Facebook page, the ethical considerations of virality were raised. The article analyzes the Association of Internet Researchers guidelines, Facebook policies, and the context of privacy in relation to virality. Virality creates the leverage for methodological pluralism. The nature of the inquiry can determine the method rather than the other way around. Viral ethical considerations are evolving due to the cyber world becoming the primary meme of communication, with flexibility in the researcher's protocol providing opportunities for efficient, cost-effective, and diverse recruitment.

  3. Characterization of the viral O-glycopeptidome

    DEFF Research Database (Denmark)

    Cló, Emiliano; Kracun, Stjepan K; Nudelman, Aaron S

    2012-01-01

    Viral envelope proteins mediate interactions with host cells, leading to internalization and intracellular propagation. Envelope proteins are glycosylated and are known to serve important functions in masking host immunity to viral glycoproteins. However, the viral infectious cycle in cells may...... also lead to aberrant glycosylation that may elicit immunity. Our knowledge of immunity to aberrant viral glycans and glycoproteins is limited, potentially due to technical limitations in identifying immunogenic glycans and glycopeptide epitopes. This work describes three different complementary...... methods for high-throughput screening and identification of potential immunodominant O-glycopeptide epitopes on viral envelope glycoproteins: (i) on-chip enzymatic glycosylation of scan peptides, (ii) chemical glycopeptide microarray synthesis, and (iii) a one-bead-one-compound random glycopeptide library...

  4. Localization of latency-associated nuclear antigen (LANA) on mitotic chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Rahayu, Retno; Ohsaki, Eriko [Division of Virology, Department of Microbiology and Immunology, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871 (Japan); Omori, Hiroko [Central Instrumentation Laboratory Research Institute for Microbial Diseases (BIKEN), Osaka University, Osaka 565-0871 (Japan); Ueda, Keiji, E-mail: kueda@virus.med.osaka-u.ac.jp [Division of Virology, Department of Microbiology and Immunology, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871 (Japan)

    2016-09-15

    In latent infection of Kaposi's sarcoma-associated herpesvirus (KSHV), viral gene expression is extremely limited and copy numbers of viral genomes remain constant. Latency-associated nuclear antigen (LANA) is known to have a role in maintaining viral genome copy numbers in growing cells. Several studies have shown that LANA is localized in particular regions on mitotic chromosomes, such as centromeres/pericentromeres. We independently examined the distinct localization of LANA on mitotic chromosomes during mitosis, using super-resolution laser confocal microscopy and correlative fluorescence microscopy–electron microscopy (FM-EM) analyses. We found that the majority of LANA were not localized at particular regions such as telomeres/peritelomeres, centromeres/pericentromeres, and cohesion sites, but at the bodies of condensed chromosomes. Thus, LANA may undergo various interactions with the host factors on the condensed chromosomes in order to tether the viral genome to mitotic chromosomes and realize faithful viral genome segregation during cell division. - Highlights: • This is the first report showing LANA dots on mitotic chromosomes by fluorescent microscopy followed by electron microscopy. • LANA dots localized randomly on condensed chromosomes other than centromere/pericentromere and telomere/peritelomre. • Cellular mitotic checkpoint should not be always involved in the segregation of KSHV genomes in the latency.

  5. Experimental infection with non-cytopathic bovine viral diarrhea virus 1 in mice induces inflammatory cell infiltration in the spleen.

    Science.gov (United States)

    Han, Yu-Jung; Kwon, Young-Je; Lee, Kyung-Hyun; Choi, Eun-Jin; Choi, Kyoung-Seong

    2016-09-01

    Previously, our study showed that oral inoculation of mice with cytopathic (cp) bovine viral diarrhea virus (BVDV) led to lymphocyte depletion and increased numbers of megakaryocytes in the spleen as well as thrombocytopenia and lymphopenia. In the present study, to investigate the possible differences in the detection of viral antigen, histopathological lesions, and hematologic changes between non-cytopathic (ncp) BVDV1 and cp BVDV1, mice were orally administered low and high doses of ncp BVDV1 and were necropsied at days 0, 2, 5, and 9 postinfection (pi). None of the ncp BVDV1-infected mice exhibited clinical signs of illness, unlike those infected with cp BVDV1. Statistically significant thrombocytopenia was observed during ncp BVDV1 infection, and lymphopenia was found only in mice infected with a high dose at day 9 pi. Interestingly, ncp BVDV1 infection increased the numbers of basophils, eosinophils, neutrophils, and monocytes in some infected mice. Viral antigen was detected in the lymphocytes of the spleen, mesenteric lymph nodes, Peyer's patches, and bone marrow by immunohistochemistry. Lymphoid depletion was evident in the mesenteric lymph nodes of mice infected with a high dose and also found in the Peyer's patches of some infected mice. Infiltration of inflammatory cells, including neutrophils and monocytes, and an increased number of megakaryocytes were seen in the spleen. These results suggest that the distribution of viral antigens is not associated with the presence of histopathological lesions. Inflammatory cell infiltration was observed in the spleens as a result of viral replication and may be attributable to the host reaction to ncp BVDV1 infection. Together, these findings support the possibility that mice can be used as an animal model for BVDV infection.

  6. Antigen Export Reduces Antigen Presentation and Limits T Cell Control of M. tuberculosis.

    Science.gov (United States)

    Srivastava, Smita; Grace, Patricia S; Ernst, Joel D

    2016-01-13

    Persistence of Mycobacterium tuberculosis results from bacterial strategies that manipulate host adaptive immune responses. Infected dendritic cells (DCs) transport M. tuberculosis to local lymph nodes but activate CD4 T cells poorly, suggesting bacterial manipulation of antigen presentation. However, M. tuberculosis antigens are also exported from infected DCs and taken up and presented by uninfected DCs, possibly overcoming this blockade of antigen presentation by infected cells. Here we show that the first stage of this antigen transfer, antigen export, benefits M. tuberculosis by diverting bacterial proteins from the antigen presentation pathway. Kinesin-2 is required for antigen export and depletion of this microtubule-based motor increases activation of antigen-specific CD4 T cells by infected cells and improves control of intracellular infection. Thus, although antigen transfer enables presentation by bystander cells, it does not compensate for reduced antigen presentation by infected cells and represents a bacterial strategy for CD4 T cell evasion.

  7. CD4+ T cell-mediated presentation of non-infectious HIV-1virion antigens to HIV-specific CD8+ T cells

    Institute of Scientific and Technical Information of China (English)

    XU Jian-qing; Franco Lori; Julianna Lisziewicz

    2006-01-01

    Background The mechanism of chronic immune activation and impairment of HIV-specific immune responses during chronic infection is not fully understood. However, it is known that high immune activation leads to more rapid progression to AIDS. We hypothesize that CD4+ T cell-mediated viral antigen presentation contributes to this pathologic immune activation in HIV-infected individuals.Methods HIV-specific T cells, responding to noninfectious HIV-1 virions as antigen, were measured by flow cytometric assays. These experimental conditions reflect the in vivo condition where noninfectious HIV-1 represents more than 99% of the antigens.Results CD4+ T cells purified from HIV-infected individuals were capable of cross presenting exogenous noninfectious HIV-1 virions to HIV-1-specific CD8+ T cells. Cross presentation required the entry of HIV-1 to CD4+ T cells and antigen translocation from endoplasmic reticulum to the Golgi complex. Blocking CD4+mediated activation of HIV-specific CD8+ T cells and redirecting the viral antigens to antigen presenting cells improved HIV-specific T cell responses.Conclusions One possible cause of chronic immune activation and impairment of HIV-1 specific T cell responses is represented by HIV-1 harboring CD4+ T cells cross presenting HIV-1 antigen to activate CD8+ T cells. This new mechanism provides the first evidence that cross presentation of noninfectious HIV-1. Virions play a role in the immunopathogenesis of HIV-1 infection.

  8. Detection of Hepatitis B Virus Antigens in Paraffin-embedded Liver Specimens from the Amazon Region, Brazil

    Directory of Open Access Journals (Sweden)

    Simonetti SRR

    2002-01-01

    Full Text Available Hepatic viscerotomy of paraffin-preserved old specimens, collected in the period from 1934 to 1967, were analyzed by immunohistochemical assays to detect hepatitis B, hepatitis D, dengue and yellow fever virus antigens. The material belongs to the Yellow Fever Collection, Department of Pathology, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil and the cases were diagnosed at that time according to clinical aspects and histopathological findings reporting viral hepatitis, yellow fever, focal necrosis and hepatic atrophy. From the 79 specimens, 69 were collected at the Labrea Region and the other 10 in different other localities in the Amazon Region. The five micra thick histological slices were analyzed for the presence of hepatitis B surface antigen (HBsAg and hepatitis B core antigen (HBcAg by immunoperoxidase technique. An immunofluorescence assay was applied to the detection of hepatitis D, yellow fever and dengue virus antigens. Nine (11.4% histological samples were HBsAg reactive and 5 (6.3% were HBcAg reactive. The oldest reactive sample was from 1934. Viral antigens related to the other pathologies were not detected in this study. Our results confirm that the methodology described may be used to elucidate the aetiology of hepatitis diseases even after a long time of conservation of the specimens.

  9. THE LYMPH SELF ANTIGEN REPERTOIRE

    Directory of Open Access Journals (Sweden)

    Laura eSantambrogio

    2013-12-01

    Full Text Available The lymphatic fluid originates from the interstitial fluid which bathes every parenchymal organ and reflects the omic composition of the tissue from which it originates in its physiological or pathological signature. Several recent proteomic analyses have mapped the proteome-degradome and peptidome of this immunologically relevant fluid pointing to the lymph as an important source of tissue-derived self-antigens. A vast array of lymph-circulating peptides have been mapped deriving from a variety of processing pathways including caspases, cathepsins, MMPs, ADAMs, kallikreins, calpains and granzymes, among others. These self peptides can be directly loaded on circulatory dendritic cells and expand the self-antigenic repertoire available for central and peripheral tolerance.

  10. iNKT Cells and Their potential Lipid Ligands during Viral Infection

    Directory of Open Access Journals (Sweden)

    Anunya eOpasawatchai

    2015-07-01

    Full Text Available Invariant natural killer T (iNKT cells are a unique population of lipid reactive CD1d restricted innate-like T lymphocytes. Despite being a minor population, they serve as an early source of cytokines and promote immunological crosstalk thus bridging innate and adaptive immunity. Diseases ranging from allergy, autoimmunity, and cancer as well as infectious diseases, including viral infection, have been reported to be influenced by iNKT cells. However, it remains unclear how iNKT cells are activated during viral infection, as virus derived lipid antigens have not been reported. Cytokines may activate iNKT cells during infections from influenza and murine cytomegalovirus (MCMV, although CD1d dependent activation is evident in other viral infections. Several viruses, such as dengue virus (DENV, induce CD1d upregulation which correlates with iNKT cell activation. In contrast, Herpes simplex virus type 1 (HSV-1, Human immunodeficiency virus (HIV, Epstein-Barr virus (EBV and Human papiloma virus (HPV promote CD1d downregulation as a strategy to evade iNKT cell recognition. These observations suggest the participation of a CD1d-dependent process in the activation of iNKT cells in response to viral infection. Endogenous lipid ligands, including phospholipids as well as glycosphingolipids, such as glucosylceramide have been proposed to mediate iNKT cell activation. Pro-inflammatory signals produced during viral infection may stimulate iNKT cells through enhanced CD1d dependent endogenous lipid presentation. Furthermore, viral infection may alter lipid composition and inhibit endogenous lipid degradation. Recent advances in this field are reviewed.

  11. Bacterial phospholipide antigens and their taxonomic significance.

    Science.gov (United States)

    Karalnik, B V; Razbash, M P; Akhmetova, E A

    1981-01-01

    The investigation of interrelationships between the phospholipides of various microorganisms (33 strains of corynebacteria, mycobacteria and staphylococci) using crossed antibody neutralization reactions with phospholipide antigenic erythrocyte diagnostic was used for the assessment of the degree of antigenic propinquity and antigenic differences between the phospholipides of bacteria of the same species, genus, and of different genera. The role of the determinants of the corresponding (their own) and "foreign" genera in the antigenic differences between the phospholipides of the microorganisms investigated was established. On the basis of the results obtained the conclusion has been drawn that the method of assessment of antigenic interrelationships between phospholipides can be used for the study of some taxonomic problems.

  12. [HLA antigens in juvenile rheumatoid arthritis].

    Science.gov (United States)

    Rumba, I V; Sochnev, A M; Kukaĭne, E M; Burshteĭn, A M; Benevolenskaia, L I

    1990-01-01

    Antigens of I class HLA system (locus A and B) were investigated in 67 patients of Latvian nationality suffering from juvenile rheumatoid arthritis (JRA). Associations of HLA antigens with juvenile rheumatoid arthritis partially coincided with the ones revealed earlier. Typing established an increased incidence of antigen B27 (p less than 0.01) and gaplotype A2, B40 (p less than 0.01). Antigen B15 possessed a protective action with respect to JRA. Interlocus combinations demonstrated a closer association with the disease than a single antigen. The authors also revealed markers of various clinico-anatomical variants of JRA.

  13. Identification of an antigenic domain in the N-terminal region of avian hepatitis E virus (HEV) capsid protein that is not common to swine and human HEVs.

    Science.gov (United States)

    Wang, Lizhen; Sun, Yani; Du, Taofeng; Wang, Chengbao; Xiao, Shuqi; Mu, Yang; Zhang, Gaiping; Liu, Lihong; Widén, Frederik; Hsu, Walter H; Zhao, Qin; Zhou, En-Min

    2014-12-01

    The antigenic domains located in the C-terminal 268 amino acid residues of avian hepatitis E virus (HEV) capsid protein have been characterized. This region shares common epitopes with swine and human HEVs. However, epitopes in the N-terminal 338 amino acid residues have never been reported. In this study, an antigenic domain located between amino acids 23 and 85 was identified by indirect ELISA using the truncated recombinant capsid proteins as coating antigens and anti-avian HEV chicken sera as primary antibodies. In addition, this domain did not react with anti-swine and human HEV sera. These results indicated that the N-terminal 338 amino acid residues of avian HEV capsid protein do not share common epitopes with swine and human HEVs. This finding is important for our understanding of the antigenicity of the avian HEV capsid protein. Furthermore, it has important implications in the selection of viral antigens for serological diagnosis.

  14. Improving the safety of viral DNA vaccines: development of vectors containing both 5' and 3' homologous regulatory sequences from non-viral origin.

    Science.gov (United States)

    Martinez-Lopez, A; Encinas, P; García-Valtanen, P; Gomez-Casado, E; Coll, J M; Estepa, A

    2013-04-01

    Although some DNA vaccines have proved to be very efficient in field trials, their authorisation still remains limited to a few countries. This is in part due to safety issues because most of them contain viral regulatory sequences to driving the expression of the encoded antigen. This is the case of the only DNA vaccine against a fish rhabdovirus (a negative ssRNA virus), authorised in Canada, despite the important economic losses that these viruses cause to aquaculture all over the world. In an attempt to solve this problem and using as a model a non-authorised, but efficient DNA vaccine against the fish rhabdovirus, viral haemorrhagic septicaemia virus (VHSV), we developed a plasmid construction containing regulatory sequences exclusively from fish origin. The result was an "all-fish vector", named pJAC-G, containing 5' and 3' regulatory sequences of β-acting genes from carp and zebrafish, respectively. In vitro and in vivo, pJAC-G drove a successful expression of the VHSV glycoprotein G (G), the only antigen of the virus conferring in vivo protection. Furthermore, and by means of in vitro fusion assays, it was confirmed that G protein expressed from pJAC-G was fully functional. Altogether, these results suggest that DNA vaccines containing host-homologous gene regulatory sequences might be useful for developing safer DNA vaccines, while they also might be useful for basic studies.

  15. DNA-guided hepatitis B treatment, viral load is essential,but not sufficient

    Institute of Scientific and Technical Information of China (English)

    Rafael Bárcena Marugán; Silvia García Garzón

    2009-01-01

    Hepatitis B virus (HBV) infection is a global public health problem that concerns 350 million people worldwide. Individuals with chronic hepatitis B (CHB) are at increased risk of developing liver cirrhosis,hepat i c de- compensation and hepatocellular carcinoma. To maintain undetectable viral load reduces chronic infection complications. There is no treatment that eradicates HBV infection. Current drugs are expensive, are associated with adverse events, and are of limited efficacy. Current guidelines try to standardize the clinical practice. Nevertheless, controversy remains about management of asymptomatic patients with CHB who are hepatitis B e antigen (HBeAg)-positive with normal alanine aminotransferase, and what is the cut-off value of viral load to distinguish HBeAgnegative CHB patients and inactive carriers. We discuss in detail why DNA level alone is not sufficient to begin treatment of CHB.

  16. Carbohydrate 19.9 Antigen Serum Levels in Liver Disease

    Directory of Open Access Journals (Sweden)

    Gaetano Bertino

    2013-01-01

    Full Text Available Background. Carbohydrate 19.9 antigen (CA19.9 has been used in the diagnosis and followup of gastrointestinal tumours. The aim of this prospective longitudinal study was the evaluation of CA19.9 levels in patients with chronic hepatitis and hepatic cirrhosis hepatitis C virus and B virus correlated. Materials and Methods. 180 patients were enrolled, 116 with HCV-related chronic liver disease (48% chronic hepatitis, 52% cirrhosis and 64 with HBV-related chronic liver disease (86% chronic hepatitis, 14% cirrhosis. Patients with high levels of CA19.9 underwent abdominal ecography, gastroendoscopy, colonoscopy, and abdominal CT scan. Results. 51.7% of patients with HCV-related chronic liver disease and 48.4% of those with HBV-related chronic liver disease presented high levels of CA19.9. None was affected by pancreatic or intestinal neoplasia, cholestatic jaundice, or other diseases potentially able to induce Ca19.9 elevations. CA19.9 levels were elevated in 43.3% of HCV chronic hepatitis, in 56.3% of HCV cirrhosis, in 45.1% of HBV chronic hepatitis, and in 58% of HBV cirrhosis. Conclusions. CA19.9 commonly increases in the serum of patients with chronic viral hepatitis. Elevation of CA 19.9 is not specific for neoplastic disease and is related to the severity of fibrosis and to the viral aetiology of hepatitis.

  17. Differential Recognition and Hydrolysis of Host Carbohydrate Antigens by Streptococcus pneumoniae Family 98 Glycoside Hydrolases

    Energy Technology Data Exchange (ETDEWEB)

    Higgins, M.; Whitworth, G; El Warry, N; Randriantsoa, M; Samain, E; Burke, R; Vocadlo, D; Boraston, A

    2009-01-01

    The presence of a fucose utilization operon in the Streptococcus pneumoniae genome and its established importance in virulence indicates a reliance of this bacterium on the harvesting of host fucose-containing glycans. The identities of these glycans, however, and how they are harvested is presently unknown. The biochemical and high resolution x-ray crystallographic analysis of two family 98 glycoside hydrolases (GH98s) from distinctive forms of the fucose utilization operon that originate from different S. pneumoniae strains reveal that one enzyme, the predominant type among pneumococcal isolates, has a unique endo-{beta}-galactosidase activity on the LewisY antigen. Altered active site topography in the other species of GH98 enzyme tune its endo-{beta}-galactosidase activity to the blood group A and B antigens. Despite their different specificities, these enzymes, and by extension all family 98 glycoside hydrolases, use an inverting catalytic mechanism. Many bacterial and viral pathogens exploit host carbohydrate antigens for adherence as a precursor to colonization or infection. However, this is the first evidence of bacterial endoglycosidase enzymes that are known to play a role in virulence and are specific for distinct host carbohydrate antigens. The strain-specific distribution of two distinct types of GH98 enzymes further suggests that S. pneumoniae strains may specialize to exploit host-specific antigens that vary from host to host, a factor that may feature in whether a strain is capable of colonizing a host or establishing an invasive infection.

  18. Distribution of caprine arthritis encephalitis virus provirus, RNA, and antigen in the reproductive tract of one naturally and seven experimentally infected bucks.

    Science.gov (United States)

    Turchetti, Andréia P; Paniago, Juliana J; da Costa, Luciana F; da Cruz, Juliano C M; Braz, Gissandra F; Gouveia, Aurora M G; Paixão, Tatiane A; Santos, Renato L; Heinemann, Marcos B

    2013-11-01

    Caprine arthritis encephalitis is a worldwide, multisystemic disease caused by a small ruminant lentivirus. Although the main route of transmission is oral, detection of proviral DNA of the caprine arthritis encephalitis virus (CAEV) in caprine semen has been previously described. However, the presence of viral antigens in the male reproductive tract has apparently never been reported. The objective was to study lesions in the buck reproductive system and to detect, in these tissues, the presence of proviral DNA, viral RNA and CAEV antigens. Tissues from eight CAEV-infected bucks (one naturally and seven experimentally infected) were analyzed by histopathology, nested polymerase chain reaction, reverse transcriptase-polymerase chain reaction, and immunohistochemistry. Interstitial pneumonia, synovitis, and lesions in the male reproductive tract were detected in some of the bucks. Proviral DNA was detected in the lungs and joints as well as in the reproductive systems of all animals, whereas viral RNA was detected only in the genital tract of the naturally infected buck. Viral antigens were immunostained in most of the organs of the male reproductive tract. This report was apparently the first to clearly demonstrate CAEV antigen expression in the male reproductive tract, which indicates the possibility of venereal transmission of CAEV.

  19. Assembly of viral genomes from metagenomes

    Directory of Open Access Journals (Sweden)

    Saskia L Smits

    2014-12-01

    Full Text Available Viral infections remain a serious global health issue. Metagenomic approaches are increasingly used in the detection of novel viral pathogens but also to generate complete genomes of uncultivated viruses. In silico identification of complete viral genomes from sequence data would allow rapid phylogenetic characterization of these new viruses. Often, however, complete viral genomes are not recovered, but rather several distinct contigs derived from a single entity, some of which have no sequence homology to any known proteins. De novo assembly of single viruses from a metagenome is challenging, not only because of the lack of a reference genome, but also because of intrapopulation variation and uneven or insufficient coverage. Here we explored different assembly algorithms, remote homology searches, genome-specific sequence motifs, k-mer frequency ranking, and coverage profile binning to detect and obtain viral target genomes from metagenomes. All methods were tested on 454-generated sequencing datasets containing three recently described RNA viruses with a relatively large genome which were divergent to previously known viruses from the viral families Rhabdoviridae and Coronaviridae. Depending on specific characteristics of the target virus and the metagenomic community, different assembly and in silico gap closure strategies were successful in obtaining near complete viral genomes.

  20. Immunological techniques in viral hepatitis.

    Science.gov (United States)

    Rehermann, Barbara; Naoumov, Nikolai V

    2007-03-01

    The need to quantitate and monitor immune responses of large patient cohorts with standardized techniques is increasing due to the growing range of treatment options for hepatitis B and hepatitis C, the development of combination therapies, and candidate experimental vaccines for HCV. In addition, advances in immunological techniques have provided new tools for detailed phenotypic and functional analysis of cellular immune responses. At present, there is substantial variation in laboratory protocols, reagents, controls and analysis and presentation of results. Standardization of immunological assays would therefore allow better comparison of results amongst individual laboratories and patient cohorts. The EASL-sponsored and AASLD-endorsed Monothematic Conference on Clinical Immunology in Viral Hepatitis was held at the University College London, United Kingdom, Oct 7-8, 2006 to bring together investigators with research experience in clinical immunology of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections for in-depth discussion, critical evaluation and standardization of immunological assays. This report summarizes the information presented and discussed at the conference, but is not intended to represent a consensus statement. Our aim is to highlight topics and issues that were supported by general agreement and those that were controversial, as well as to provide suggestions for future work.

  1. [Treatment of viral hepatitis C].

    Science.gov (United States)

    Chassany, O

    1996-12-14

    Viral hepatitis C is a serious public health problem in France by the number of infected patients, the evolutive profile and by the lack of fully efficient therapeutics. However, the risk of developing cirrhosis and hepatocellular carcinoma may not be so high as it has been stated until now. Interferon alpha is at the present time, the only approved drug for the treatment of chronic hepatitis C. Its efficiency on criteria such as normalization of aminotransferases values or negativation of viremia is obtained in less than 25% of patients. The present recommendation is to use 3 MU of interferon alpha, 3 times per week during 12 months. While interferon leads to improvement of histologic lesions, it is not yet proved that a treatment by interferon can reduce, years after, the incidence of cirrhosis and hepatocellular carcinoma. No therapeutic strategy has been defined yet for the frequent situations of "no response", relapses or presence of factors that reduce the efficacy of treatment (high initial viremia level, genotype 1b, cirrhosis). It is possible that the course of patients having low or no elevation of aminotransferases and/or minimal histologic lesions, is good without any treatment. The efficacy of interferon alone appears insufficient. Thus trials in progress concern associations of antiviral drugs such as vidarabine. In lack of vaccine, preventive treatment is essential and depends upon knowledge of conditions of transmission of the virus. Transmission through blood and intravenous drug addiction represent 60 to 70% of cases of hepatitis C.

  2. Stable solid-phase Rh antigen.

    Science.gov (United States)

    Yared, M A; Moise, K J; Rodkey, L S

    1997-12-01

    Numerous investigators have attempted to isolate the Rh antigens in a stable, immunologically reactive form since the discovery of the Rh system over 56 years ago. We report here a successful and reproducible approach to solubilizing and adsorbing the human Rh antigen(s) to a solid-phase matrix in an antigenically active form. Similar results were obtained with rabbit A/D/F red blood cell antigens. The antigen preparation was made by dissolution of the red blood cell membrane lipid followed by fragmentation of the residual cytoskeleton in an EDTA solution at low ionic strength. The antigenic activity of the soluble preparations was labile in standard buffers but was stable in zwitterionic buffers for extended periods of time. Further studies showed that the antigenic activity of these preparations was enhanced, as was their affinity for plastic surfaces, in the presence of acidic zwitterionic buffers. Adherence to plastic surfaces at low pH maintained antigenic reactivity and specificity for antibody was retained. The data show that this approach yields a stable form of antigenically active human Rh D antigen that could be used in a red blood cell-free assay for quantitative analysis of Rh D antibody and for Rh D antibody immunoadsorption and purification.

  3. Common antigens between hydatid cyst and cancers

    Directory of Open Access Journals (Sweden)

    Shima Daneshpour

    2016-01-01

    Full Text Available Background: Different research groups reported a negative correlation between cancers and parasitical infections. As an example, the prevalence of a hydatid cyst among patients with cancer was significantly lower than its prevalence among normal population. Tn antigens exist both in cancer and hydatid cyst. This common antigen may be involved in the effect of parasite on cancer growth. So in this work, common antigens between hydatid cyst and cancers have been investigated. Materials and Methods: Different hydatid cyst antigens including hydatid fluid, laminated and germinal layer antigens, and excretory secretory antigens of protoscolices were run in SDS PAGE and transferred to NCP paper. In western immunoblotting, those antigens were probed with sera of patients with different cancer and also sera of non-cancer patients. Also, cross reaction among excretory secretory products of cancer cells and antisera raised against different hydatid cyst antigen was investigated. Results: In western immunoblotting, antisera raised against laminated and germinal layers of hydatid cyst reacted with excretory secretory products of cancer cells. Also, a reaction was detected between hydatid cyst antigens and sera of patients with some cancers. Conclusion: Results of this work emphasize existence of common antigens between hydatid cyst and cancers. More investigation about these common antigens is recommended.

  4. Common antigens between hydatid cyst and cancers

    Science.gov (United States)

    Daneshpour, Shima; Bahadoran, Mehran; Hejazi, Seyed Hossein; Eskandarian, Abas Ali; Mahmoudzadeh, Mehdi; Darani, Hossein Yousofi

    2016-01-01

    Background: Different research groups reported a negative correlation between cancers and parasitical infections. As an example, the prevalence of a hydatid cyst among patients with cancer was significantly lower than its prevalence among normal population. Tn antigens exist both in cancer and hydatid cyst. This common antigen may be involved in the effect of parasite on cancer growth. So in this work, common antigens between hydatid cyst and cancers have been investigated. Materials and Methods: Different hydatid cyst antigens including hydatid fluid, laminated and germinal layer antigens, and excretory secretory antigens of protoscolices were run in SDS PAGE and transferred to NCP paper. In western immunoblotting, those antigens were probed with sera of patients with different cancer and also sera of non-cancer patients. Also, cross reaction among excretory secretory products of cancer cells and antisera raised against different hydatid cyst antigen was investigated. Results: In western immunoblotting, antisera raised against laminated and germinal layers of hydatid cyst reacted with excretory secretory products of cancer cells. Also, a reaction was detected between hydatid cyst antigens and sera of patients with some cancers. Conclusion: Results of this work emphasize existence of common antigens between hydatid cyst and cancers. More investigation about these common antigens is recommended. PMID:26962511

  5. Host and viral factors contributing to CD8+ T cell failure in hepatitis C virus infection

    Institute of Scientific and Technical Information of China (English)

    Christoph Neumann-Haefelin; Hans Christian Spangenberg; Hubert E Blum; Robert Thimme

    2007-01-01

    Virus-specific CD8+ T cells are thought to be the major anti-viral effector cells in hepatitis C virus (HCV)infection. Indeed, viral clearance is associated with vigorous CD8+ T cell responses targeting multiple epitopes. In the chronic phase of infection, HCV-specific CD8+ T cell responses are usually weak, narrowly focused and display often functional defects regarding cytotoxicity, cytokine production, and proliferative capacity. In the last few years, different mechanisms which might contribute to the failure of HCV-specific CD8+ T cells in chronic infection have been identified,including insufficient CD4+ help, deficient CD8+ T cell differentiation, viral escape mutations, suppression by viral factors, inhibitory cytokines, inhibitory ligands, and regulatory T cells. In addition, host genetic factors such as the host's human leukocyte antigen (HLA) background may play an important role in the efficiency of the HCVspecific CD8+ T cell response and thus outcome of infection. The growing understanding of the mechanisms contributing to T cell failure and persistence of HCV infection will contribute to the development of successful immunotherapeutical and -prophylactical strategies.

  6. The yellow fever 17D vaccine virus: molecular basis of viral attenuation and its use as an expression vector

    Directory of Open Access Journals (Sweden)

    Galler R.

    1997-01-01

    Full Text Available The yellow fever (YF virus is the prototype flavivirus. The use of molecular techniques has unraveled the basic mechanisms of viral genome structure and expression. Recent trends in flavivirus research include the use of infectious clone technology with which it is possible to recover virus from cloned cDNA. Using this technique, mutations can be introduced at any point of the viral genome and their resulting effect on virus phenotype can be assessed. This approach has opened new possibilities to study several biological viral features with special emphasis on the issue of virulence/attenuation of the YF virus. The feasibility of using YF virus 17D vaccine strain, for which infectious cDNA is available, as a vector for the expression of heterologous antigens is reviewed

  7. Cell-mediated immune responses in rainbow trout after DNA immunization against the viral hemorrhagic septicemia virus

    DEFF Research Database (Denmark)

    Utke, Katrin; Kock, Holger; Schuetze, Heike

    2008-01-01

    To identify viral proteins that induce cell-mediated cytotoxicity (CMC) against viral hemorrhagic septicemia virus (VHSV)-infected cells, rainbow trout were immunized with DNA vectors encoding the glycoprotein G or the nucleocapsid protein N of VHSV. The G protein was a more potent trigger...... injection site rather than to injection sites of heterologous vaccines, suggesting the antigen specificity of homing. By demonstrating CMC responses to distinct viral proteins and homing in rainbow trout, these results substantially contribute to the understanding of the teleost immune system....... of cytotoxic cells than the N protein. Peripheral blood leukocytes (PBL) isolated from trout immunized against the G protein killed both VHSV-infected MHC class I matched (RTG-2) and VHSV-infected xenogeneic (EPC) target cells, suggesting the involvement of both cytotoxic T lymphocytes (CTL) and NK cells...

  8. Short communication. Genotyping and phylogenetic analysis of bovine viral diarrhea virus (BVDV isolates in Kosovo

    Directory of Open Access Journals (Sweden)

    Izedin Goga

    2014-03-01

    Full Text Available Three serum samples positive in Antigen ELISA BVDV have been tested to characterise genetic diversity of bovine viral diarrhea virus (BVDV in Kosovo. Samples were obtained in 2011 from heifers and were amplified by reverse transcription-polymerase chain reaction, sequenced and analysed by computer-assisted phylogenetic analysis. Amplified products and nucleotide sequence showed that all 3 isolates belonged to BVDV 1 genotype and 1b sub genotype. These results enrich the extant knowledge of BVDV and represent the first documented data about Kosovo BVDV isolates.

  9. Production of a highly immunogenic subunit ISCOM vaccine against Bovine Viral Diarrhea Virus

    DEFF Research Database (Denmark)

    Kamstrup, Søren; Roensholt, L.; Jensen, M.Holm;

    1999-01-01

    Bovine Viral Diarrhea Virus (BVDV) is a major pathogen of cattle in most countries. The main reservoir of virus in herds are BVDV persistently infected animals, which arise as a result of infection of the bovine fetus early in gestation. The spread of virus to the unborn fetus may be prevented......, concentration, and insertion of antigens into immune stimulating complexes (ISCOMs). Vaccines based on two different Danish strains of BVDV were injected into calves and the antisera produced were tested for neutralising activity against a panel of Danish BVDV strains. The two vaccines induced different...

  10. A skeptical look at viral immune evasion.

    Science.gov (United States)

    Davis, I A; Rouse, B T

    1997-12-01

    In the past several years, many viral gene products have been found to encode proteins which interfere with immune defense mechanisms. Whether these interactions between virus and immune system components are actually evasion mechanisms used during viral infections in their natural hosts remains to be proven. In vitro studies do, however, reveal several tactics which may aid viral replication and dissemination by interfering with components of both the innate and adaptive immune systems. In this manuscript, we discuss the more intensively studied of these putative in vitro evasion tactics and ponder their relevance in in vivo situations.

  11. Hepatitis C virus and ethanol alter antigen presentation in liver cells

    Institute of Scientific and Technical Information of China (English)

    Natalia A Osna

    2009-01-01

    Alcoholic patients have a high incidence of hepatitis Cvirus (HCV) infection. Alcohol consumption enhances the severity of the HCV disease course and worsens the outcome of chronic hepatitis C. The accumulation of virally infected cells in the liver is related to the HCVinduced inability of the immune system to recognizeinfected cells and to develop the immune responses. This review covers the effects of HCV proteins and ethanol on major histocompatibility complex (MHC) classⅠ- and class Ⅱ-restricted antigen presentation. Here, we discuss the liver which functions as an immune privilege organ; factors, which affect cleavage and loading of antigenic peptides onto MHC classⅠand class Ⅱ in hepatocytes and dendritic cells, and the modulating effects of ethanol and HCV on antigen presentation by liver cells. Altered antigen presentation in the liver limits the ability of the immune system to clear HCV and infected cells and contributes to disease progression. HCV by itself affects dendritic cell function, switching their cytokine profile to the suppressive phenotype of interleukin-10 (IL-10) and transforming growth factor beta (TGFβ) predominance,preventing cell maturation and allostimulation capacity.The synergistic action of ethanol with HCV results in the suppression of MHC class Ⅱ-restricted antigen presentation. In addition, ethanol metabolism and HCV proteins reduce proteasome function and interferon signaling, thereby suppressing the generation of peptides for MHC classⅠ-restricted antigen presentation.Collectively, ethanol exposure further impairs antigen presentation in HCV-infected liver cells, which may provide a partial explanation for exacerbations and the poor outcome of HCV infection in alcoholics.

  12. Epstein-Barr virus nuclear antigen 2 specifically induces expression of the B-cell activation antigen CD23

    Energy Technology Data Exchange (ETDEWEB)

    Wang, F.; Gregory, C.D.; Rowe, M.; Rickinson, A.B.; Wang, D.; Birkenbach, M.; Kikutani, H.; Kishimoto, T.; Kieff, E.

    1987-05-01

    Epstein-Barr virus (EBV) infection of EBV-negative Burkitt lymphoma (BL) cells includes some changes similar to those seen in normal B lymphocytes that have been growth transformed by EBV. The role of individual EBV genes in this process was evaluated by introducing each of the viral genes that are normally expressed in EBV growth-transformed and latently infected lymphoblasts into an EBV-negative BL cell line, using recombinant retrovirus-mediated transfer. Clones of cells were derived that stably express the EBV nuclear antigen 1 (EBNA-1), EBNA-2, EBNA-3, EBNA-leader protein, or EBV latent membrane protein (LMP). These were compared with control clones infected with the retrovirus vector. All 10 clones converted to EBNA-2 expression differed from control clones or clones expressing other EBV proteins by growth in tight clumps and by markedly increased expression of one particular surface marker of B-cell activation, CD23. Other activation antigens were unaffected by EBNA-2 expression, as were markers already expressed on the parent BL cell line. The results indicate that EBNA-2 is a specific direct or indirect trans-activator of CD23. This establishes a link between an EBV gene and cell gene expression. Since CD23 has been implicated in the transduction of B-cell growth signals, its specific induction by EBNA-2 could be important in EBV induction of B-lymphocyte transformation.

  13. Molecular diversity of bovine viral diarrhea virus in uruguay.

    Science.gov (United States)

    Maya, L; Puentes, R; Reolón, E; Acuña, P; Riet, F; Rivero, R; Cristina, J; Colina, R

    2016-03-01

    Bovine viral diarrhea (BVD) affects bovine production and reproduction causing significant economic losses all over the world. Two viral species has been recognized: BVDV-1 and BVDV-2, both distributed worldwide. Recently, novel specie of BVDV named HoBi-like pestivirus was discovered. The presence of BVDV was confirmed in 1996 in Uruguay, however, does not exist until today a schedule of compulsory vaccination along the country. Serological studies with samples from all Uruguayan herds were performed during 2000 and 2001 demonstrating that all of them were seropositive to BVDV with a mean prevalence of 69%. In addition, there have been no new studies done since those previously described and it is important to mention that the genetic diversity of BVD has never been described in Uruguay. Nowadays, there is strongly suspect that BVDV is one of the most important causes of reproductive failures in our herds. The aim of this study was to describe for the first time in Uruguay the genetic diversity of BVDV with samples collected from different regions along the country. Serological status of 390 non-vaccinated animals against BVDV with reproductive problems from farms of Rivera, Tacuarembó and Florida departments of Uruguay were studied. All herds were seropositive to BVDV and high proportion of animals were positive (298/390), while 4.1% (16/390) of the animals were positive to Antigen Capture ELISA test and Real Time PCR. Phylogenetic analysis performed with concatenated sequences from the 5'UTR and Npro genomic regions revealed that BVDV-1 and BVDV-2 are infecting our herds, being BVDV-1 the most frequently found. The major subtype was BVDV-1a, followed by BVDV-1i and BVDV-2b. This is the first study that describes the genetic diversity of BVDV in Uruguay and it will contribute to the elaboration of sanitization programs.

  14. Heterosubtypic protection against pathogenic human and avian influenza viruses via in vivo electroporation of synthetic consensus DNA antigens.

    Directory of Open Access Journals (Sweden)

    Dominick J Laddy

    Full Text Available BACKGROUND: The persistent evolution of highly pathogenic avian influenza (HPAI highlights the need for novel vaccination techniques that can quickly and effectively respond to emerging viral threats. We evaluated the use of optimized consensus influenza antigens to provide broad protection against divergent strains of H5N1 influenza in three animal models of mice, ferrets, and non-human primates. We also evaluated the use of in vivo electroporation to deliver these vaccines to overcome the immunogenicity barrier encountered in larger animal models of vaccination. METHODS AND FINDINGS: Mice, ferrets and non-human primates were immunized with consensus plasmids expressing H5 hemagglutinin (pH5HA, N1 neuraminidase (pN1NA, and nucleoprotein antigen (pNP. Dramatic IFN-gamma-based cellular immune responses to both H5 and NP, largely dependent upon CD8+ T cells were seen in mice. Hemaggutination inhibition titers classically associated with protection (>1:40 were seen in all species. Responses in both ferrets and macaques demonstrate the ability of synthetic consensus antigens to induce antibodies capable of inhibiting divergent strains of the H5N1 subtype, and studies in the mouse and ferret demonstrate the ability of synthetic consensus vaccines to induce protection even in the absence of such neutralizing antibodies. After challenge, protection from morbidity and mortality was seen in mice and ferrets, with significant reductions in viral shedding and disease progression seen in vaccinated animals. CONCLUSIONS: By combining several consensus influenza antigens with in vivo electroporation, we demonstrate that these antigens induce both protective cellular and humoral immune responses in mice, ferrets and non-human primates. We also demonstrate the ability of these antigens to protect from both morbidity and mortality in a ferret model of HPAI, in both the presence and absence of neutralizing antibody, which will be critical in responding to the

  15. NNDSS - Table II. Hepatitis (viral, acute) C

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Hepatitis (viral, acute) C - 2017. In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the preceding...

  16. NNDSS - Table II. Hepatitis (viral, acute)

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Hepatitis (viral, acute) - 2014.In this Table, all conditions with a 5-year average annual national total of more than or equals 1,000 cases but...

  17. NNDSS - Table II. Hepatitis (viral, acute)

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Hepatitis (viral, acute) - 2016. In this Table, provisional* cases of selected†notifiable diseases (≥1,000 cases reported during the preceding...

  18. Drug Use and Viral Infections (HIV, Hepatitis)

    Science.gov (United States)

    ... HIV, Hepatitis) Drug Use and Viral Infections (HIV, Hepatitis) Email Facebook Twitter Revised March 2017 What's the ... HIV and of worsening its consequences. What is hepatitis? Photo by ©iStock.com/ Skarie20 Hepatitis is an ...

  19. NNDSS - Table II. Hepatitis (viral, acute)

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Hepatitis (viral, acute) - 2015.In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the preceding...

  20. Oxygen tension level and human viral infections.

    Science.gov (United States)

    Morinet, Frédéric; Casetti, Luana; François, Jean-Hugues; Capron, Claude; Pillet, Sylvie

    2013-09-01

    The role of oxygen tension level is a well-known phenomenon that has been studied in oncology and radiotherapy since about 60 years. Oxygen tension may inhibit or stimulate propagation of viruses in vitro as well as in vivo. In turn modulating oxygen metabolism may constitute a novel approach to treat viral infections as an adjuvant therapy. The major transcription factor which regulates oxygen tension level is hypoxia-inducible factor-1 alpha (HIF-1α). Down-regulating the expression of HIF-1α is a possible method in the treatment of chronic viral infection such as human immunodeficiency virus infection, chronic hepatitis B and C viral infections and Kaposi sarcoma in addition to classic chemotherapy. The aim of this review is to supply an updating concerning the influence of oxygen tension level in human viral infections and to evoke possible new therapeutic strategies regarding this environmental condition.

  1. [Pediatrics. New treatment options for viral bronchiolitis].

    Science.gov (United States)

    Rochat, I; Hafen, G

    2013-01-16

    The combination of nebulized epinephrine and high dose dexamethasone, or nebulized hypertonic saline, are promising new therapeutic strategies for viral bronchiolitis in the young infant. However, further research is needed before a general recommendation can be given.

  2. Viral fitness: definitions, measurement, and current insights

    Science.gov (United States)

    Wargo, Andrew R.; Kurath, Gael

    2012-01-01

    Viral fitness is an active area of research, with recent work involving an expanded number of human, non-human vertebrate, invertebrate, plant, and bacterial viruses. Many publications deal with RNA viruses associated with major disease emergence events, such as HIV-1, influenza virus, and Dengue virus. Study topics include drug resistance, immune escape, viral emergence, host jumps, mutation effects, quasispecies diversity, and mathematical models of viral fitness. Important recent trends include increasing use of in vivo systems to assess vertebrate virus fitness, and a broadening of research beyond replicative fitness to also investigate transmission fitness and epidemiologic fitness. This is essential for a more integrated understanding of overall viral fitness, with implications for disease management in the future.

  3. Mechanisms of influenza viral membrane fusion.

    Science.gov (United States)

    Blijleven, Jelle S; Boonstra, Sander; Onck, Patrick R; van der Giessen, Erik; van Oijen, Antoine M

    2016-12-01

    Influenza viral particles are enveloped by a lipid bilayer. A major step in infection is fusion of the viral and host cellular membranes, a process with large kinetic barriers. Influenza membrane fusion is catalyzed by hemagglutinin (HA), a class I viral fusion protein activated by low pH. The exact nature of the HA conformational changes that deliver the energy required for fusion remains poorly understood. This review summarizes our current knowledge of HA structure and dynamics, describes recent single-particle experiments and modeling studies, and discusses their role in understanding how multiple HAs mediate fusion. These approaches provide a mechanistic picture in which HAs independently and stochastically insert into the target membrane, forming a cluster of HAs that is collectively able to overcome the barrier to membrane fusion. The new experimental and modeling approaches described in this review hold promise for a more complete understanding of other viral fusion systems and the protein systems responsible for cellular fusion.

  4. A Rapid Method for Viral Particle Detection in Viral-Induced Gastroenteritis: A TEM Study

    Science.gov (United States)

    Hicks, M. John; Barrish, James P.; Hayes, Elizabeth S.; Leer, Laurie C.; Estes, Mary K.; Cubitt, W. D.

    1995-10-01

    Infectious gastroenteritis is a common cause of hospitalization in the pediatric population. The most frequent cause of gastroenteritis is viral in origin. The purpose of this study was to compare a rapid modified negative-staining TEM method with the conventional pseudoreplica technique in detection of viral particles in fecal samples from children with viral gastroenteritis. The modified negative-staining method resulted in a significantly higher (2.5 ± 0.5, p = 0.02) viral rating score than that for the conventional pseudoreplica technique (1.7 ± 0.4). In addition, the preparation time for the negative-staining method was approximately one fifth that for the conventional pseudoreplica technique. Rapid diagnosis of viral gastroenteritis may be made by ultrastructural detection of viral particles in fecal samples using the negative staining technique.

  5. Institute of Medicine's Report on Viral Hepatitis

    Centers for Disease Control (CDC) Podcasts

    2010-05-18

    In this podcast, Dr. John Ward, Director of CDC’s Division of Viral Hepatitis, discusses the 2010 report, Hepatitis and Liver Cancer: A National Strategy for Prevention and Control of Hepatitis B and C, from the Institute of Medicine.  Created: 5/18/2010 by National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP).   Date Released: 5/18/2010.

  6. Rapid and highly fieldable viral diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    McKnight, Timothy E.

    2016-12-20

    The present invention relates to a rapid, highly fieldable, nearly reagentless diagnostic to identify active RNA viral replication in a live, infected cells, and more particularly in leukocytes and tissue samples (including biopsies and nasal swabs) using an array of a plurality of vertically-aligned nanostructures that impale the cells and introduce a DNA reporter construct that is expressed and amplified in the presence of active viral replication.

  7. Pur-Alpha Induces JCV Gene Expression and Viral Replication by Suppressing SRSF1 in Glial Cells.

    Directory of Open Access Journals (Sweden)

    Ilker Kudret Sariyer

    Full Text Available PML is a rare and fatal demyelinating disease of the CNS caused by the human polyomavirus, JC virus (JCV, which occurs in AIDS patients and those on immunosuppressive monoclonal antibody therapies (mAbs. We sought to identify mechanisms that could stimulate reactivation of JCV in a cell culture model system and targeted pathways which could affect early gene transcription and JCV T-antigen production, which are key steps of the viral life cycle for blocking reactivation of JCV. Two important regulatory partners we have previously identified for T-antigen include Pur-alpha and SRSF1 (SF2/ASF. SRSF1, an alternative splicing factor, is a potential regulator of JCV whose overexpression in glial cells strongly suppresses viral gene expression and replication. Pur-alpha has been most extensively characterized as a sequence-specific DNA- and RNA-binding protein which directs both viral gene transcription and mRNA translation, and is a potent inducer of the JCV early promoter through binding to T-antigen.Pur-alpha and SRSF1 both act directly as transcriptional regulators of the JCV promoter and here we have observed that Pur-alpha is capable of ameliorating SRSF1-mediated suppression of JCV gene expression and viral replication. Interestingly, Pur-alpha exerted its effect by suppressing SRSF1 at both the protein and mRNA levels in glial cells suggesting this effect can occur independent of T-antigen. Pur-alpha and SRSF1 were both localized to oligodendrocyte inclusion bodies by immunohistochemistry in brain sections from patients with HIV-1 associated PML. Interestingly, inclusion bodies were typically positive for either Pur-alpha or SRSF1, though some cells appeared to be positive for both proteins.Taken together, these results indicate the presence of an antagonistic interaction between these two proteins in regulating of JCV gene expression and viral replication and suggests that they play an important role during viral reactivation leading to

  8. Generating viral metagenomes from the coral holobiont

    Directory of Open Access Journals (Sweden)

    Karen Dawn Weynberg

    2014-05-01

    Full Text Available Reef-building corals comprise multipartite symbioses where the cnidarian animal is host to an array of eukaryotic and prokaryotic organisms, and the viruses that infect them. These viruses are critical elements of the coral holobiont, serving not only as agents of mortality, but also as potential vectors for lateral gene flow, and as elements encoding a variety of auxiliary metabolic functions. Consequently, understanding the functioning and health of the coral holobiont requires detailed knowledge of the associated viral assemblage and its function. Currently, the most tractable way of uncovering viral diversity and function is through metagenomic approaches, which is inherently difficult in corals because of the complex holobiont community, an extracellular mucus layer that all corals secrete, and the variety of sizes and structures of nucleic acids found in viruses. Here we present the first protocol for isolating, purifying and amplifying viral nucleic acids from corals based on mechanical disruption of cells. This method produces at least 50% higher yields of viral nucleic acids, has very low levels of cellular sequence contamination and captures wider viral diversity than previously used chemical-based extraction methods. We demonstrate that our mechanical-based method profiles a greater diversity of DNA and RNA genomes, including virus groups such as Retro-transcribing and ssRNA viruses, which are absent from metagenomes generated via chemical-based methods. In addition, we briefly present (and make publically available the first paired DNA and RNA viral metagenomes from the coral Acropora tenuis.

  9. Mesenchymal Stromal Cells and Viral Infection

    Directory of Open Access Journals (Sweden)

    Maytawan Thanunchai

    2015-01-01

    Full Text Available Mesenchymal Stromal Cells (MSCs are a subset of nonhematopoietic adult stem cells, readily isolated from various tissues and easily culture-expanded ex vivo. Intensive studies of the immune modulation and tissue regeneration over the past few years have demonstrated the great potential of MSCs for the prevention and treatment of steroid-resistant acute graft-versus-host disease (GvHD, immune-related disorders, and viral diseases. In immunocompromised individuals, the immunomodulatory activities of MSCs have raised safety concerns regarding the greater risk of primary viral infection and viral reactivation, which is a major cause of mortality after allogeneic transplantation. Moreover, high susceptibilities of MSCs to viral infections in vitro could reflect the destructive outcomes that might impair the clinical efficacy of MSCs infusion. However, the interplay between MSCs and virus is like a double-edge sword, and it also provides beneficial effects such as allowing the proliferation and function of antiviral specific effector cells instead of suppressing them, serving as an ideal tool for study of viral pathogenesis, and protecting hosts against viral challenge by using the antimicrobial activity. Here, we therefore review favorable and unfavorable consequences of MSCs and virus interaction with the highlight of safety and efficacy for applying MSCs as cell therapy.

  10. Viral Metagenomics: MetaView Software

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    Zhou, C; Smith, J

    2007-10-22

    The purpose of this report is to design and develop a tool for analysis of raw sequence read data from viral metagenomics experiments. The tool should compare read sequences of known viral nucleic acid sequence data and enable a user to attempt to determine, with some degree of confidence, what virus groups may be present in the sample. This project was conducted in two phases. In phase 1 we surveyed the literature and examined existing metagenomics tools to educate ourselves and to more precisely define the problem of analyzing raw read data from viral metagenomic experiments. In phase 2 we devised an approach and built a prototype code and database. This code takes viral metagenomic read data in fasta format as input and accesses all complete viral genomes from Kpath for sequence comparison. The system executes at the UNIX command line, producing output that is stored in an Oracle relational database. We provide here a description of the approach we came up with for handling un-assembled, short read data sets from viral metagenomics experiments. We include a discussion of the current MetaView code capabilities and additional functionality that we believe should be added, should additional funding be acquired to continue the work.

  11. Bioinformatics tools for analysing viral genomic data.

    Science.gov (United States)

    Orton, R J; Gu, Q; Hughes, J; Maabar, M; Modha, S; Vattipally, S B; Wilkie, G S; Davison, A J

    2016-04-01

    The field of viral genomics and bioinformatics is experiencing a strong resurgence due to high-throughput sequencing (HTS) technology, which enables the rapid and cost-effective sequencing and subsequent assembly of large numbers of viral genomes. In addition, the unprecedented power of HTS technologies has enabled the analysis of intra-host viral diversity and quasispecies dynamics in relation to important biological questions on viral transmission, vaccine resistance and host jumping. HTS also enables the rapid identification of both known and potentially new viruses from field and clinical samples, thus adding new tools to the fields of viral discovery and metagenomics. Bioinformatics has been central to the rise of HTS applications because new algorithms and software tools are continually needed to process and analyse the large, complex datasets generated in this rapidly evolving area. In this paper, the authors give a brief overview of the main bioinformatics tools available for viral genomic research, with a particular emphasis on HTS technologies and their main applications. They summarise the major steps in various HTS analyses, starting with quality control of raw reads and encompassing activities ranging from consensus and de novo genome assembly to variant calling and metagenomics, as well as RNA sequencing.

  12. Oxygen tension level and human viral infections

    Energy Technology Data Exchange (ETDEWEB)

    Morinet, Frédéric, E-mail: frederic.morinet@sls.aphp.fr [Centre des Innovations Thérapeutiques en Oncologie et Hématologie (CITOH), CHU Saint-Louis, Paris (France); Université Denis Diderot, Sorbonne Paris Cité Paris, Paris (France); Casetti, Luana [Institut Cochin INSERM U1016, Paris (France); François, Jean-Hugues; Capron, Claude [Institut Cochin INSERM U1016, Paris (France); Laboratoire d' Hématologie, Hôpital Ambroise Paré, Boulogne (France); Université de Versailles Saint-Quentin en Yvelynes, Versailles (France); Pillet, Sylvie [Laboratoire de Bactériologie-Virologie-Hygiène, CHU de Saint-Etienne, Saint-Etienne (France); Université de Lyon et Université de Saint-Etienne, Jean Monnet, GIMAP EA3064, F-42023 Saint-Etienne, Lyon (France)

    2013-09-15

    The role of oxygen tension level is a well-known phenomenon that has been studied in oncology and radiotherapy since about 60 years. Oxygen tension may inhibit or stimulate propagation of viruses in vitro as well as in vivo. In turn modulating oxygen metabolism may constitute a novel approach to treat viral infections as an adjuvant therapy. The major transcription factor which regulates oxygen tension level is hypoxia-inducible factor-1 alpha (HIF-1α). Down-regulating the expression of HIF-1α is a possible method in the treatment of chronic viral infection such as human immunodeficiency virus infection, chronic hepatitis B and C viral infections and Kaposi sarcoma in addition to classic chemotherapy. The aim of this review is to supply an updating concerning the influence of oxygen tension level in human viral infections and to evoke possible new therapeutic strategies regarding this environmental condition. - Highlights: • Oxygen tension level regulates viral replication in vitro and possibly in vivo. • Hypoxia-inducible factor 1 (HIF-1α) is the principal factor involved in Oxygen tension level. • HIF-1α upregulates gene expression for example of HIV, JC and Kaposi sarcoma viruses. • In addition to classical chemotherapy inhibition of HIF-1α may constitute a new track to treat human viral infections.

  13. Cell-Free versus Cell-to-Cell Infection by Human Immunodeficiency Virus Type 1 and Human T-Lymphotropic Virus Type 1: Exploring the Link among Viral Source, Viral Trafficking, and Viral Replication.

    Science.gov (United States)

    Dutartre, Hélène; Clavière, Mathieu; Journo, Chloé; Mahieux, Renaud

    2016-09-01

    Human immunodeficiency virus type 1 (HIV-1) and human T-lymphotropic virus type 1 (HTLV-1) are complex retroviruses mainly infecting CD4(+) T lymphocytes. In addition, antigen-presenting cells such as dendritic cells (DCs) are targeted in vivo by both viruses, although to a lesser extent. Interaction of HIV-1 with DCs plays a key role in viral dissemination from the mucosa to CD4(+) T lymphocytes present in lymphoid organs. While similar mechanisms may occur for HTLV-1 as well, most HTLV-1 data were obtained from T-cell studies, and little is known regarding the trafficking of this virus in DCs. We first compared the efficiency of cell-free versus cell-associated viral sources of both retroviruses at infecting DCs. We showed that both HIV-1 and HTLV-1 cell-free particles are poorly efficient at productively infecting DCs, except when DC-SIGN has been engaged. Furthermore, while SAMHD-1 accounts for restriction of cell-free HIV-1 infection, it is not involved in HTLV-1 restriction. In addition, cell-free viruses lead mainly to a nonproductive DC infection, leading to trans-infection of T-cells, a process important for HIV-1 spread but not for that of HTLV-1. Finally, we show that T-DC cell-to-cell transfer implies viral trafficking in vesicles that may both increase productive infection of DCs ("cis-infection") and allow viral escape from immune surveillance. Altogether, these observations allowed us to draw a model of HTLV-1 and HIV-1 trafficking in DCs.

  14. Comparing viral metagenomics methods using a highly multiplexed human viral pathogens reagent.

    Science.gov (United States)

    Li, Linlin; Deng, Xutao; Mee, Edward T; Collot-Teixeira, Sophie; Anderson, Rob; Schepelmann, Silke; Minor, Philip D; Delwart, Eric

    2015-03-01

    Unbiased metagenomic sequencing holds significant potential as a diagnostic tool for the simultaneous detection of any previously genetically described viral nucleic acids in clinical samples. Viral genome sequences can also inform on likely phenotypes including drug susceptibility or neutralization serotypes. In this study, different variables of the laboratory methods often used to generate viral metagenomics libraries were compared for their abilities to detect multiple viruses and generate full genome coverage. A biological reagent consisting of 25 different human RNA and DNA viral pathogens was used to estimate the effect of filtration and nuclease digestion, DNA/RNA extraction methods, pre-amplification and the use of different library preparation kits on the detection of viral nucleic acids. Filtration and nuclease treatment led to slight decreases in the percentage of viral sequence reads and number of viruses detected. For nucleic acid extractions silica spin columns improved viral sequence recovery relative to magnetic beads and Trizol extraction. Pre-amplification using random RT-PCR while generating more viral sequence reads resulted in detection of fewer viruses, more overlapping sequences, and lower genome coverage. The ScriptSeq library preparation method retrieved more viruses and a greater fraction of their genomes than the TruSeq and Nextera methods. Viral metagenomics sequencing was able to simultaneously detect up to 22 different viruses in the biological reagent analyzed including all those detected by qPCR. Further optimization will be required for the detection of viruses in biologically more complex samples such as tissues, blood, or feces.

  15. mRNA Structural constraints on EBNA1 synthesis impact on in vivo antigen presentation and early priming of CD8+ T cells.

    Directory of Open Access Journals (Sweden)

    Judy T Tellam

    2014-10-01

    Full Text Available Recent studies have shown that virally encoded mRNA sequences of genome maintenance proteins from herpesviruses contain clusters of unusual structural elements, G-quadruplexes, which modulate viral protein synthesis. Destabilization of these G-quadruplexes can override the inhibitory effect on self-synthesis of these proteins. Here we show that the purine-rich repetitive mRNA sequence of Epstein-Barr virus encoded nuclear antigen 1 (EBNA1 comprising G-quadruplex structures, limits both the presentation of MHC class I-restricted CD8(+ T cell epitopes by CD11c(+ dendritic cells in draining lymph nodes and early priming of antigen-specific CD8(+ T-cells. Destabilization of the G-quadruplex structures through codon-modification significantly enhanced in vivo antigen presentation and activation of virus-specific T cells. Ex vivo imaging of draining lymph nodes by confocal microscopy revealed enhanced antigen-specific T-cell trafficking and APC-CD8(+ T-cell interactions in mice primed with viral vectors encoding a codon-modified EBNA1 protein. More importantly, these antigen-specific T cells displayed enhanced expression of the T-box transcription factor and superior polyfunctionality consistent with the qualitative impact of translation efficiency. These results provide an important insight into how viruses exploit mRNA structure to down regulate synthesis of their viral maintenance proteins and delay priming of antigen-specific T cells, thereby establishing a successful latent infection in vivo. Furthermore, targeting EBNA1 mRNA rather than protein by small molecules or antisense oligonucleotides will enhance EBNA1 synthesis and the early priming of effector T cells, to establish a more rapid immune response and prevent persistent infection.

  16. Surface-expressed viral proteins in feline infectious peritonitis virus-infected monocytes are internalized through a clathrin- and caveolae-independent pathway.

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    Dewerchin, Hannah L; Cornelissen, Els; Van Hamme, Evelien; Smits, Kaatje; Verhasselt, Bruno; Nauwynck, Hans J

    2008-11-01

    Infection with feline infectious peritonitis virus (FIPV), a feline coronavirus, frequently leads to death in spite of a strong humoral immune response. In previous work, we reported that infected monocytes, the in vivo target cells of FIPV, express viral proteins in their plasma membranes. These proteins are quickly internalized upon binding of antibodies. As the cell surface is cleared from viral proteins, internalization might offer protection against antibody-dependent cell lysis. Here, the internalization and subsequent trafficking of the antigen-antibody complexes were characterized using biochemical, cell biological and genetic approaches. Internalization occurred through a clathrin- and caveolae-independent pathway that did not require dynamin, rafts, actin or rho-GTPases. These findings indicate that the viral antigen-antibody complexes were not internalized through any of the previously described pathways. Further characterization showed that this internalization process was independent from phosphatases and tyrosine kinases but did depend on serine/threonine kinases. After internalization, the viral antigen-antibody complexes passed through the early endosomes, where they resided only briefly, and accumulated in the late endosomes. Between 30 and 60 min after antibody addition, the complexes left the late endosomes but were not degraded in the lysosomes. This study reveals what is probably a new internalization pathway into primary monocytes, confirming once more the complexity of endocytic processes.

  17. An Odyssey to Viral Pathogenesis.

    Science.gov (United States)

    Oldstone, Michael B A

    2016-05-23

    polishing by Karl Habel (a superb senior virologist who left the National Institutes of Health and came to Scripps), and the gifted postdoctoral fellows who joined my laboratory over four decades form the log of my scientific voyage. The strong friendships and collaborations developed with other young but growing experimentalists like Bernie Fields and Abner Notkins are the fabric of the tale I will weave and were pivotal in the establishment of viral pathogenesis as a discipline.

  18. Structure, Receptor Binding, and Antigenicity of Influenza Virus Hemagglutinins from the 1957 H2N2 Pandemic

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Rui; McBride, Ryan; Paulson, James C.; Basler, Christopher F.; Wilson, Ian A. (Sinai); (Scripps)

    2010-03-04

    The hemagglutinin (HA) envelope protein of influenza viruses mediates essential viral functions, including receptor binding and membrane fusion, and is the major viral antigen for antibody neutralization. The 1957 H2N2 subtype (Asian flu) was one of the three great influenza pandemics of the last century and caused 1 million deaths globally from 1957 to 1968. Three crystal structures of 1957 H2 HAs have been determined at 1.60 to 1.75 {angstrom} resolutions to investigate the structural basis for their antigenicity and evolution from avian to human binding specificity that contributed to its introduction into the human population. These structures, which represent the highest resolutions yet recorded for a complete ectodomain of a glycosylated viral surface antigen, along with the results of glycan microarray binding analysis, suggest that a hydrophobicity switch at residue 226 and elongation of receptor-binding sites were both critical for avian H2 HA to acquire human receptor specificity. H2 influenza viruses continue to circulate in birds and pigs and, therefore, remain a substantial threat for transmission to humans. The H2 HA structure also reveals a highly conserved epitope that could be harnessed in the design of a broader and more universal influenza A virus vaccine.

  19. PreC and C Regions of Woodchuck Hepatitis Virus Facilitate Persistent Expression of Surface Antigen of Chimeric WHV-HBV Virus in the Hydrodynamic Injection BALB/c Mouse Model

    Science.gov (United States)

    Wu, Weimin; Liu, Yan; Lin, Yong; Pan, Danzhen; Yang, Dongliang; Lu, Mengji; Xu, Yang

    2017-01-01

    In the hydrodynamic injection (HI) BALB/c mouse model with the overlength viral genome, we have found that woodchuck hepatitis virus (WHV) could persist for a prolonged period of time (up to 45 weeks), while hepatitis B virus (HBV) was mostly cleared at week four. In this study, we constructed a series of chimeric genomes based on HBV and WHV, in which the individual sequences of a 1.3-fold overlength HBV genome in pBS-HBV1.3 were replaced by their counterparts from WHV. After HI with the WHV-HBV chimeric constructs in BALB/c mice, serum viral antigen, viral DNA (vDNA), and intrahepatic viral antigen expression were analyzed to evaluate the persistence of the chimeric genomes. Interestingly, we found that HI with three chimeric WHV-HBV genomes resulted in persistent antigenemia in mice. All of the persistent chimeric genomes contained the preC region and the part of the C region encoding the N-terminal 1–145 amino acids of the WHV genome. These results indicated that the preC region and the N-terminal part of the C region of the WHV genome may play a role in the persistent antigenemia. The chimeric WHV-HBV genomes were able to stably express viral antigens in the liver and could be further used to express hepadnaviral antigens to study their pathogenic potential. PMID:28230775

  20. [Antigenic relationships between Debaryomyces strains (author's transl)].

    Science.gov (United States)

    Aksoycan, N

    1980-01-01

    The results of the agglutinations between homologous and heterologous Debaryomyces strains and their agglutinating sera are shown in table I. According to these findings, D. hansenii and D. marama are antigenically different from other Debaryomyces strains in this genus. In a previous study Aksoycan et al. have shown a common antigenic factor between D. hansenii, D. marama strains and Salmonella 0:7 antigen. This factor was not present in other six strains of Debaryomyces. These results also show that D. tamarii does not have any antigenic relationship with the other seven species of Debaryomyces in this genus.

  1. Complexities in Isolation and Purification of Multiple Viruses from Mixed Viral Infections: Viral Interference, Persistence and Exclusion.

    Directory of Open Access Journals (Sweden)

    Naveen Kumar

    Full Text Available Successful purification of multiple viruses from mixed infections remains a challenge. In this study, we investigated peste des petits ruminants virus (PPRV and foot-and-mouth disease virus (FMDV mixed infection in goats. Rather than in a single cell type, cytopathic effect (CPE of the virus was observed in cocultured Vero/BHK-21 cells at 6th blind passage (BP. PPRV, but not FMDV could be purified from the virus mixture by plaque assay. Viral RNA (mixture transfection in BHK-21 cells produced FMDV but not PPRV virions, a strategy which we have successfully employed for the first time to eliminate the negative-stranded RNA virus from the virus mixture. FMDV phenotypes, such as replication competent but noncytolytic, cytolytic but defective in plaque formation and, cytolytic but defective in both plaque formation and standard FMDV genome were observed respectively, at passage level BP8, BP15 and BP19 and hence complicated virus isolation in the cell culture system. Mixed infection was not found to induce any significant antigenic and genetic diversity in both PPRV and FMDV. Further, we for the first time demonstrated the viral interference between PPRV and FMDV. Prior transfection of PPRV RNA, but not Newcastle disease virus (NDV and rotavirus RNA resulted in reduced FMDV replication in BHK-21 cells suggesting that the PPRV RNA-induced interference was specifically directed against FMDV. On long-term coinfection of some acute pathogenic viruses (all possible combinations of PPRV, FMDV, NDV and buffalopox virus in Vero cells, in most cases, one of the coinfecting viruses was excluded at passage level 5 suggesting that the long-term coinfection may modify viral persistence. To the best of our knowledge, this is the first documented evidence describing a natural mixed infection of FMDV and PPRV. The study not only provides simple and reliable methodologies for isolation and purification of two epidemiologically and economically important groups of

  2. Prospects for cannabinoid therapies in viral encephalitis.

    Science.gov (United States)

    Solbrig, Marylou V; Fan, Yijun; Hazelton, Paul

    2013-11-06

    Cannabinoids are promising therapies to support neurogenesis and decelerate disease progression in neuroinflammatory and degenerative disorders. Whether neuroprotective effects of cannabinoids are sustainable during persistent viral infection of the CNS is not known. Using a rodent model of chronic viral encephalitis based on Borna Disease (BD) virus, in which 1 week treatment with the general cannabinoid WIN 55,212-2 has been shown to be neuroprotective (Solbrig et al., 2010), we examine longer term (2 week treatment) effects of a general (CB1 and CB2) cannabinoid receptor agonist WIN55,212-2 (1mg/kg ip twice per day) or a specific (CB2) cannabinoid receptor agonist HU-308 (5mg/kg ip once daily) on histopathology, measures of frontostriatal neurogenesis and gliogenesis, and viral load. We find that WIN and HU-308 differ in their ability to protect new BrdU(+) cells. The selective CB2 agonist HU increases BrdU(+) cells in prefrontal cortex (PFC), significantly increases BrdU(+) cells in striatum, differentially regulates polydendrocytes vs. microglia/macrophages, and reduces immune activation at a time WIN-treated rats appear tolerant to the anti-inflammatory effect of their cannabinoid treatment. WIN and HU had little direct viral effect in PFC and striatum, yet reduced viral signal in hippocampus. Thus, HU-308 action on CB2 receptors, receptors known to be renewed during microglia proliferation and action, is a nontolerizing mechanism of controlling CNS inflammation during viral encephalitis by reducing microglia activation, as well as partially limiting viral infection, and uses a nonpsychotropic cannabinoid agonist.

  3. Dicer-2 processes diverse viral RNA species.

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    Leah R Sabin

    Full Text Available RNA silencing pathways play critical roles in gene regulation, virus infection, and transposon control. RNA interference (RNAi is mediated by small interfering RNAs (siRNAs, which are liberated from double-stranded (dsRNA precursors by Dicer and guide the RNA-induced silencing complex (RISC to targets. Although principles governing small RNA sorting into RISC have been uncovered, the spectrum of RNA species that can be targeted by Dicer proteins, particularly the viral RNAs present during an infection, are poorly understood. Dicer-2 potently restricts viral infection in insects by generating virus-derived siRNAs from viral RNA. To better characterize the substrates of Dicer-2, we examined the virus-derived siRNAs produced during the Drosophila antiviral RNAi response to four different viruses using high-throughput sequencing. We found that each virus was uniquely targeted by the RNAi pathway; dicing substrates included dsRNA replication intermediates and intramolecular RNA stem loops. For instance, a putative intergenic RNA hairpin encoded by Rift Valley Fever virus generates abundant small RNAs in both Drosophila and mosquito cells, while repetitive sequences within the genomic termini of Vaccinia virus, which give rise to abundant small RNAs in Drosophila, were found to be transcribed in both insect and mammalian cells. Moreover, we provide evidence that the RNA species targeted by Dicer-2 can be modulated by the presence of a viral suppressor of RNAi. This study uncovered several novel, heavily targeted features within viral genomes, offering insight into viral replication, viral immune evasion strategies, and the mechanism of antiviral RNAi.

  4. Molecular piracy: the viral link to carcinogenesis.

    Science.gov (United States)

    Flaitz, C M; Hicks, M J

    1998-11-01

    The vast majority of the human experience with viral infections is associated with acute symptoms, such as malaise, fever, chills, rhinitis and diarrhea. With this acute or lytic phase, the immune system mounts a response and eliminates the viral agent while acquiring antibodies to that specific viral subtype. With latent or chronic infections, the viral agent becomes incorporated into the human genome. Viral agents capable of integration into the host's genetic material are particularly dangerous and may commandeer the host's ability to regulate normal cell growth and proliferation. The oncogenic viruses may immortalize the host cell, and facilitate malignant transformation. Cell growth and proliferation may be enhanced by viral interference with tumor suppressor gene function (p53 and pRb). Viruses may act as vectors for mutated proto-oncogenes (oncogenes). Overexpression of these oncogenes in viral-infected cells interferes with normal cell function and allows unregulated cell growth and proliferation, which may lead to malignant transformation and tumour formation. Development of oral neoplasms, both benign and malignant, has been linked to several viruses. Epstein-Barr virus is associated with oral hairy leukoplakia, lymphoproliferative disease, lymphoepithelial carcinoma, B-cell lymphomas, and nasopharyngeal carcinoma. Human herpesvirus-8 has been implicated in all forms of Kaposi's sarcoma, primary effusion lymphomas, multiple myeloma, angioimmunoblastic lymphadenopathy, and Castleman's disease. Human herpesvirus-6 has been detected in lymphoproliferative disease, lymphomas, Hodgkin's disease, and oral squamous cell carcinoma. The role of human papillomavirus in benign (squamous papilloma, focal epithelial hyperplasia, condyloma acuminatum, verruca vulgaris), premalignant (oral epithelial dysplasia), and malignant (squamous cell carcinoma) neoplasms within the oral cavity is well recognized. Herpes simplex virus may participate as a cofactor in oral squamous

  5. Platelets and infection — an emerging role of platelets in viral infection

    Directory of Open Access Journals (Sweden)

    Alice eAssinger

    2014-12-01

    Full Text Available Platelets are anucleate blood cells that play a crucial role in the maintenance of hemostasis. While platelet activation and elevated platelet counts (thrombocytosis are associated with increased risk of thrombotic complications, low platelet counts (thrombocytopenia and several platelet function disorders increase the risk of bleeding. Over the last years more and more evidence has emerged that platelets and their activation state can also modulate innate and adaptive immune responses and low platelet counts have been identified as a surrogate marker for poor prognosis in septic patients.Viral infections often coincide with platelet activation. Host inflammatory responses result in the release of platelet activating mediators and a pro-oxidative and pro-coagulant environment, which favours platelet activation. However, viruses can also directly interact with platelets and megakaryocytes and modulate their function. Furthermore, platelets can be activated by viral antigen-antibody complexes and in response to some viruses B-lymphocytes also generate anti-platelet antibodies.All these processes contributing to platelet activation result in increased platelet consumption and removal and often lead to thrombocytopenia, which is frequently observed during viral infection. However, virus-induced platelet activation does not only modulate platelet count, but also shapes immune responses. Platelets and their released products have been reported to directly and indirectly suppress infection and to support virus persistence in response to certain viruses, making platelets a double-edged sword during viral infections. This review aims to summarize the current knowledge on platelet interaction with different types of viruses, the viral impact on platelet activation and platelet-mediated modulations of innate and adaptive immune responses.

  6. Platelets and infection - an emerging role of platelets in viral infection.

    Science.gov (United States)

    Assinger, Alice

    2014-01-01

    Platelets are anucleate blood cells that play a crucial role in the maintenance of hemostasis. While platelet activation and elevated platelet counts (thrombocytosis) are associated with increased risk of thrombotic complications, low platelet counts (thrombocytopenia) and several platelet function disorders increase the risk of bleeding. Over the last years, more and more evidence has emerged that platelets and their activation state can also modulate innate and adaptive immune responses and low platelet counts have been identified as a surrogate marker for poor prognosis in septic patients. Viral infections often coincide with platelet activation. Host inflammatory responses result in the release of platelet activating mediators and a pro-oxidative and pro-coagulant environment, which favors platelet activation. However, viruses can also directly interact with platelets and megakaryocytes and modulate their function. Furthermore, platelets can be activated by viral antigen-antibody complexes and in response to some viruses B-lymphocytes also generate anti-platelet antibodies. All these processes contributing to platelet activation result in increased platelet consumption and removal and often lead to thrombocytopenia, which is frequently observed during viral infection. However, virus-induced platelet activation does not only modulate platelet count but also shape immune responses. Platelets and their released products have been reported to directly and indirectly suppress infection and to support virus persistence in response to certain viruses, making platelets a double-edged sword during viral infections. This review aims to summarize the current knowledge on platelet interaction with different types of viruses, the viral impact on platelet activation, and platelet-mediated modulations of innate and adaptive immune responses.

  7. Genomic Loads and Genotypes of Respiratory Syncytial Virus: Viral Factors during Lower Respiratory Tract Infection in Chilean Hospitalized Infants

    Science.gov (United States)

    Espinosa, Yazmín; San Martín, Camila; Torres, Alejandro A.; Farfán, Mauricio J.; Torres, Juan P.; Avadhanula, Vasanthi; Piedra, Pedro A.; Tapia, Lorena I.

    2017-01-01

    The clinical impact of viral factors (types and viral loads) during respiratory syncytial virus (RSV) infection is still controversial, especially regarding newly described genotypes. In this study, infants with RSV bronchiolitis were recruited to describe the association of these viral factors with severity of infection. RSV antigenic types, genotypes, and viral loads were determined from hospitalized patients at Hospital Roberto del Río, Santiago, Chile. Cases were characterized by demographic and clinical information, including days of lower respiratory symptoms and severity. A total of 86 patients were included: 49 moderate and 37 severe cases. During 2013, RSV-A was dominant (86%). RSV-B predominated in 2014 (92%). Phylogenetic analyses revealed circulation of GA2, Buenos Aires (BA), and Ontario (ON) genotypes. No association was observed between severity of infection and RSV group (p = 0.69) or genotype (p = 0.87). After a clinical categorization of duration of illness, higher RSV genomic loads were detected in infants evaluated earlier in their disease (p < 0.001) and also in infants evaluated later, but coursing a more severe infection (p = 0.04). Although types and genotypes did not associate with severity in our children, higher RSV genomic loads and delayed viral clearance in severe patients define a group that might benefit from new antiviral therapies. PMID:28335547

  8. KSHV encoded LANA recruits Nucleosome Assembly Protein NAP1L1 for regulating viral DNA replication and transcription

    Science.gov (United States)

    Gupta, Namrata; Thakker, Suhani; Verma, Subhash C.

    2016-09-01

    The establishment of latency is an essential for lifelong persistence and pathogenesis of Kaposi’s sarcoma-associated herpesvirus (KSHV). Latency-associated nuclear antigen (LANA) is the most abundantly expressed protein during latency and is important for viral genome replication and transcription. Replication-coupled nucleosome assembly is a major step in packaging the newly synthesized DNA into chromatin, but the mechanism of KSHV genome chromatinization post-replication is not understood. Here, we show that nucleosome assembly protein 1-like protein 1 (NAP1L1) associates with LANA. Our binding assays revealed an association of LANA with NAP1L1 in KSHV-infected cells, which binds through its amino terminal domain. Association of these proteins confirmed their localization in specific nuclear compartments of the infected cells. Chromatin immunoprecipitation assays from NAP1L1-depleted cells showed LANA-mediated recruitment of NAP1L1 at the terminal repeat (TR) region of the viral genome. Presence of NAP1L1 stimulated LANA-mediated DNA replication and persistence of a TR-containing plasmid. Depletion of NAP1L1 led to a reduced nucleosome positioning on the viral genome. Furthermore, depletion of NAP1L1 increased the transcription of viral lytic genes and overexpression decreased the promoter activities of LANA-regulated genes. These results confirmed that LANA recruitment of NAP1L1 helps in assembling nucleosome for the chromatinization of newly synthesized viral DNA.

  9. A systematic approach for the identification of novel, serologically reactive recombinant Varicella-Zoster Virus (VZV antigens

    Directory of Open Access Journals (Sweden)

    Lueking Angelika

    2010-07-01

    Full Text Available Abstract Background Varicella-Zoster virus causes chickenpox upon primary infection and shingles after reactivation. Currently available serological tests to detect VZV-specific antibodies are exclusively based on antigens derived from VZV-infected cells. Results We present a systematic approach for the identification of novel, serologically reactive VZV antigens. Therefore, all VZV open reading frames were cloned into a bacterial expression vector and checked for small scale recombinant protein expression. Serum profiling experiments using purified VZV proteins and clinically defined sera in a microarray revealed 5 putative antigens (ORFs 1, 4, 14, 49, and 68. These were rearranged in line format and validated with pre-characterized sera. Conclusions The line assay confirmed the seroreactivity of the identified antigens and revealed its suitability for VZV serodiagnostics comparable to commercially available VZV-ELISA. Recombinant ORF68 (gE proved to be an antigen for high-confidence determination of VZV serostatus. Furthermore, our data suggest that a serological differentiation between chickenpox and herpes zoster may be possible by analysis of the IgM-portfolio against individual viral antigens.

  10. Development of an enzyme immunoassay for poliovirus antigens

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    Newton Hashimoto

    2007-01-01

    Full Text Available An indirect solid-phase enzyme immunoassay (EIA was developed for the detection of poliovirus antigen. Virus antigen was obtained in LLC-MK2 cell cultures and used to prepare antibodies in rabbit and guinea pig. Antibodies were evaluated by double immunodiffusion and neutralization test. Optimal concentrations of guinea pig and rabbit immunoglobulins were determined by checkerboard titration. Microtitre plates were coated with 15.0 µg/ml guinea pig anti-polio immunoglobulin and rabbit anti-polio immunoglobulin at the concentration of 7.94 µg/ml was used as detecting antibody. The standard curve with eight different antigen concentrations in eight replicates resulted in a coefficient of variation (CV between 2.1% to 7.8%. The dose-response relationship was determined by simple linear regression with a coefficient of correlation (R² equal to 96.4%. The assay detected a minimum of 2.3 µg/ml poliovirus antigen.O trabalho apresenta o desenvolvimento de um ensaio imunoenzimático indireto para a detecção de antígeno de poliovírus. O antígeno viral foi obtido em cultura de células LLC-MK2 e usado para imunização de coelho e cobaia. Os soros hiperimunes foram avaliados por imunodifusão dupla e teste de neutralização. Após padronização, o soro de captura, produzido em cobaia, foi usado na concentração protéica de 15.0 µg/ml para sensibilizar microplacas de poliestireno e o soro de coelho (detector foi usado na concentração de 7.94 µg/ml. A curva padrão resultante da utilização de oito diferentes concentrações do antígeno padrão definiu um coeficiente de variação de 2.1% a 7.8%. A relação dose-resposta foi determinada por regressão linear simples com o estabelecimento do coeficiente de correlação (R² igual a 96.4%. O ensaio possibilitou a detecção mínima de 2.3 µg/ml de antígeno de poliovírus.

  11. Blastogenic response of human lymphocytes to early antigen(s) of human cytomegalovirus.

    OpenAIRE

    Waner, J L; Kong, N; Biano, S

    1983-01-01

    The lymphocytes of asymptomatic, seropositive donors demonstrated blastogenic responses to early antigens of human cytomegalovirus whether or not antibodies to early antigens were detectable. The lymphocytes of six of nine patients with active cytomegalovirus infections gave stimulation indexes of greater than or equal to 2.00 with antigens of productively infected cells, whereas only two patients demonstrated comparable stimulation indexes with early antigens. Four patients with stimulation ...

  12. Alzheimer's disease gene signature says: beware of brain viral infections

    Directory of Open Access Journals (Sweden)

    Ianni Manuela

    2010-12-01

    Full Text Available Abstract Background Recent findings from a genome wide association investigation in a large cohort of patients with Alzheimer's disease (AD and non demented controls (CTR showed that a limited set of genes was in a strong association (p > l0-5 with the disease. Presentation of the hypothesis In this report we suggest that the polymorphism association in 8 of these genes is consistent with a non conventional interpretation of AD etiology. Nectin-2 (NC-2, apolipoprotein E (APOE, glycoprotein carcinoembryonic antigen related cell adhesion molecule- 16 (CEACAM-16, B-cell lymphoma-3 (Bcl-3, translocase of outer mitochondrial membrane 40 homolog (T0MM-40, complement receptor-1 (CR-l, APOJ or clusterin and C-type lectin domain A family-16 member (CLEC-16A result in a genetic signature that might affect individual brain susceptibility to infection by herpes virus family during aging, leading to neuronal loss, inflammation and amyloid deposition. Implications of the hypothesis We hypothesized that such genetic trait may predispose to AD via complex and diverse mechanisms each contributing to an increase of individual susceptibility to brain viral infections

  13. Enhanced cytotoxicity of natural killer cells following the acquisition of chimeric antigen receptors through trogocytosis.

    Directory of Open Access Journals (Sweden)

    Fu-Nan Cho

    Full Text Available Natural killer (NK cells have the capacity to target tumors and are ideal candidates for immunotherapy. Viral vectors have been used to genetically modify in vitro expanded NK cells to express chimeric antigen receptors (CARs, which confer cytotoxicity against tumors. However, use of viral transduction methods raises the safety concern of viral integration into the NK cell genome. In this study, we used trogocytosis as a non-viral method to modify NK cells for immunotherapy. A K562 cell line expressing high levels of anti-CD19 CARs was generated as a donor cell to transfer the anti-CD19 CARs onto NK cells via trogocytosis. Anti-CD19 CAR expression was observed in expanded NK cells after these cells were co-cultured for one hour with freeze/thaw-treated donor cells expressing anti-CD19 CARs. Immunofluorescence analysis confirmed the localization of the anti-CD19 CARs on the NK cell surface. Acquisition of anti-CD19 CARs via trogocytosis enhanced NK cell-mediated cytotoxicity against the B-cell acute lymphoblastic leukemia (B-ALL cell lines and primary B-ALL cells derived from patients. To our knowledge, this is the first report that describes the increased cytotoxicity of NK cells following the acquisition of CARs via trogocytosis. This novel strategy could be a potential valuable therapeutic approach for the treatment of B-cell tumors.

  14. Modification of a salmonid alphavirus replicon vector for enhanced expression of heterologous antigens.

    Science.gov (United States)

    Guo, Tz-Chun; Johansson, Daniel X; Liljeström, Peter; Evensen, Øystein; Haugland, Øyvind

    2015-03-01

    A salmonid alphavirus (SAV) replicon has been developed to express heterologous antigens but protein production was low to modest compared with terrestrial alphavirus replicons. In this study, we have compared several modifications to a SAV replicon construct and analysed their influence on foreign gene expression. We found that an insertion of a translational enhancer consisting of the N-terminal 102 nt of the capsid gene, together with a nucleotide sequence encoding the foot-and-mouth disease virus (FMDV) 2A peptide, caused a significant increase in EGFP reporter gene expression. The importance of fusing a hammerhead (HH) ribozyme sequence at the 5' end of the viral genome was also demonstrated. In contrast, a hepatitis D virus ribozyme (HDV-RZ) sequence placed at the 3' end did not augment expression of inserted genes. Taken together, we have developed a platform for optimized antigen production, which can be applied for immunization of salmonid fish in the future.

  15. A computational framework for influenza antigenic cartography.

    Directory of Open Access Journals (Sweden)

    Zhipeng Cai

    Full Text Available Influenza viruses have been responsible for large losses of lives around the world and continue to present a great public health challenge. Antigenic characterization based on hemagglutination inhibition (HI assay is one of the routine procedures for influenza vaccine strain selection. However, HI assay is only a crude experiment reflecting the antigenic correlations among testing antigens (viruses and reference antisera (antibodies. Moreover, antigenic characterization is usually based on more than one HI dataset. The combination of multiple datasets results in an incomplete HI matrix with many unobserved entries. This paper proposes a new computational framework for constructing an influenza antigenic cartography from this incomplete matrix, which we refer to as Matrix Completion-Multidimensional Scaling (MC-MDS. In this approach, we first reconstruct the HI matrices with viruses and antibodies using low-rank matrix completion, and then generate the two-dimensional antigenic cartography using multidimensional scaling. Moreover, for influenza HI tables with herd immunity effect (such as those from Human influenza viruses, we propose a temporal model to reduce the inherent temporal bias of HI tables caused by herd immunity. By applying our method in HI datasets containing H3N2 influenza A viruses isolated from 1968 to 2003, we identified eleven clusters of antigenic variants, representing all major antigenic drift events in these 36 years. Our results showed that both the completed HI matrix and the antigenic cartography obtained via MC-MDS are useful in identifying influenza antigenic variants and thus can be used to facilitate influenza vaccine strain selection. The webserver is available at http://sysbio.cvm.msstate.edu/AntigenMap.

  16. A computational framework for influenza antigenic cartography.

    Science.gov (United States)

    Cai, Zhipeng; Zhang, Tong; Wan, Xiu-Feng

    2010-10-07

    Influenza viruses have been responsible for large losses of lives around the world and continue to present a great public health challenge. Antigenic characterization based on hemagglutination inhibition (HI) assay is one of the routine procedures for influenza vaccine strain selection. However, HI assay is only a crude experiment reflecting the antigenic correlations among testing antigens (viruses) and reference antisera (antibodies). Moreover, antigenic characterization is usually based on more than one HI dataset. The combination of multiple datasets results in an incomplete HI matrix with many unobserved entries. This paper proposes a new computational framework for constructing an influenza antigenic cartography from this incomplete matrix, which we refer to as Matrix Completion-Multidimensional Scaling (MC-MDS). In this approach, we first reconstruct the HI matrices with viruses and antibodies using low-rank matrix completion, and then generate the two-dimensional antigenic cartography using multidimensional scaling. Moreover, for influenza HI tables with herd immunity effect (such as those from Human influenza viruses), we propose a temporal model to reduce the inherent temporal bias of HI tables caused by herd immunity. By applying our method in HI datasets containing H3N2 influenza A viruses isolated from 1968 to 2003, we identified eleven clusters of antigenic variants, representing all major antigenic drift events in these 36 years. Our results showed that both the completed HI matrix and the antigenic cartography obtained via MC-MDS are useful in identifying influenza antigenic variants and thus can be used to facilitate influenza vaccine strain selection. The webserver is available at http://sysbio.cvm.msstate.edu/AntigenMap.

  17. Temporal relation of antigenaemia and loss of antibodies to core antigens to development of clinical disease in HIV infection

    DEFF Research Database (Denmark)

    Pedersen, C; Nielsen, C M; Vestergaard, B F;

    1987-01-01

    A total of 276 sequential serum samples from 34 men with antibodies to the human immunodeficiency virus (HIV) followed up for two to seven years were analysed for HIV antigen and antibodies to the viral core and envelope proteins. Results were correlated with clinical outcome and CD4 T lymphocyte...... with antigenaemia compared with one out of 18 patients without antigenaemia. Low counts of CD4 cells (less than 0.5 X 10(9)/l) were found in 14 of the 16 patients with antigenaemia and five of the 18 without antigenaemia. Nine patients seroconverted to HIV during the study; two of these developed antigenaemia 14...... and 16 months after the estimated time of seroconversion. These results show that the late stages of HIV infection are characterised by increased production of antigen and a decrease in antibodies directed against the core protein. Antigenaemia indicates a poor prognosis; and as the antigen test...

  18. A computational method for identification of vaccine targets from protein regions of conserved human leukocyte antigen binding

    DEFF Research Database (Denmark)

    Olsen, Lars Rønn; Simon, Christian; Kudahl, Ulrich J.;

    2015-01-01

    target diverse regions in highly variable viral pathogens and this diversity may need to be addressed through redefinition of suitable peptide targets. Methods: We have developed a method for antigen assessment and target selection for polyvalent vaccines, with which we identified immune epitopes from...... the number of potential vaccine targets compared to the number of targets discovered using the traditional approach where low-frequency peptides are excluded. Conclusions: We developed a webserver with an intuitive visualization scheme for summarizing the T cell-based antigenic potential of any given protein......Background: Computational methods for T cell-based vaccine target discovery focus on selection of highly conserved peptides identified across pathogen variants, followed by prediction of their binding of human leukocyte antigen molecules. However, experimental studies have shown that T cells often...

  19. Fish viral infections in northwest of Spain.

    Science.gov (United States)

    Ledo, A; Lupiani, B; Dopazo, C P; Toranzo, A E; Barja, J L

    1990-06-01

    During a three years survey, a total of 149 samples from 20 farms of rainbow trout, salmon and turbot were examined for the presence of virus with the purpose to study the viral infections affecting cultured fish and their incidence in the fishfarms of Northwestern Spain. Infectious pancreatic necrosis virus (IPNV) was the only viral agent isolated from salmonid fish. Fry and fingerlings of trout showed the highest infection rate (24%). This virus was not detected in broodstock or embryonated eggs, although it was isolated from ovaric and seminal fluids and from juvenile carriers. From 24 samples of salmon analyzed, IPNV was only detected in one sample of juveniles. Examination of turbot led the isolation of a new virus belonging to the reoviridae family, which affected to the ongrowing population. All of the IPNV tested belonged to serotype Sp regardless of the origin of the trout stocks. During the monitorization of imported embryonated eggs, no virus was detected from any of the samples. However, in some case, IPNV was isolated when testing the fry obtained in our laboratory from those samples of imported eggs. Our findings indicate that: i) the analysis of fingerlings increase the probability to detect viral infections allowing us an optimal control of importations, and ii) most of the viral infections of fish take place in the own fish farms. The detection of mixed viral and bacterial infections emphasize the importance of carrying out an integral microbiological analysis to determine the causal agent(s) of fish mortalities.

  20. Regulatory T cells in viral hepatitis

    Institute of Scientific and Technical Information of China (English)

    Eva Billerbeck; Tobias B(o)ttler; Robert Thimme

    2007-01-01

    The pathogenesis and outcome of viral infections are significantly influenced by the host immune response.The immune system is able to eliminate many viruses in the acute phase of infection. However, some viruses,like hepatitis C virus (HCV) and hepatitis B virus (HBV),can evade the host immune responses and establish a persistent infection. HCV and HBV persistence is caused by various mechanisms, like subversion of innate immune responses by viral factors, the emergence of T cell escape mutations, or T cell dysfunction and suppression.Recently, it has become evident that regulatory T cells may contribute to the pathogenesis and outcome of viral infections by suppressing antiviral immune responses.Indeed, the control of HCV and HBV specific immune responses mediated by regulatory T cells may be one mechanism that favors viral persistence, but it may also prevent the host from overwhelming T cell activity and liver damage. This review will focus on the role of regulatory T cells in viral hepatitis.

  1. Viral genome sequencing by random priming methods

    Directory of Open Access Journals (Sweden)

    Zhang Xinsheng

    2008-01-01

    Full Text Available Abstract Background Most emerging health threats are of zoonotic origin. For the overwhelming majority, their causative agents are RNA viruses which include but are not limited to HIV, Influenza, SARS, Ebola, Dengue, and Hantavirus. Of increasing importance therefore is a better understanding of global viral diversity to enable better surveillance and prediction of pandemic threats; this will require rapid and flexible methods for complete viral genome sequencing. Results We have adapted the SISPA methodology 123 to genome sequencing of RNA and DNA viruses. We have demonstrated the utility of the method on various types and sources of viruses, obtaining near complete genome sequence of viruses ranging in size from 3,000–15,000 kb with a median depth of coverage of 14.33. We used this technique to generate full viral genome sequence in the presence of host contaminants, using viral preparations from cell culture supernatant, allantoic fluid and fecal matter. Conclusion The method described is of great utility in generating whole genome assemblies for viruses with little or no available sequence information, viruses from greatly divergent families, previously uncharacterized viruses, or to more fully describe mixed viral infections.

  2. Pancreatic involvement in chronic viral hepatitis

    Institute of Scientific and Technical Information of China (English)

    Yoshiki Katakura; Hiroshi Yotsuyanagi; Kiyoe Hashizume; Chiaki Okuse; Noriaki Okuse; Kohji Nishikawa; Michihiro Suzuki; Shiro Iino; Fumio Itoh

    2005-01-01

    AIM: To elucidate the frequency and characteristics of pancreatic disorders in the course of chronic viral hepatitis. METHODS: We prospectively assessed the serum pancreatic enzyme levels and imaging findings in patients with chronic viral hepatitis and healthy control subjects. RESULTS: Serum amylase (t-Amy), salivary amylase (s-Amy), pancreatic amylase (p-Amy) and serum lipase levels were higher in hepatitis patients in comparison to control subjects. However, in asymptomatic viral carriers, only the serum t-Amy levels were higher than those of the controls. The levels of each enzyme rose with the progression of liver disease in patients with hepatitis B or C; whereas the levels of each enzyme within the same clinical stage of the disease did not differ between patients diagnosed with either hepatitis B or hepatitis C virus. Imaging findings demonstrated chronic pancreatitis in only 1 out of 202 patients (0.5%).CONCLUSION: Our data suggest that serum levels of pancreatic enzymes increase with the progression of liver disease in patients diagnosed with viral hepatitis. Pancreatic disease, asymptomatic in most cases, may represent an extrahepatic manifestation of chronic viral hepatitis.

  3. Mapping the antigenic structure of porcine parvovirus at the level of peptides

    DEFF Research Database (Denmark)

    Kamstrup, Søren; Langeveld, Jan; Bøtner, Anette;

    1998-01-01

    located in the region corresponding to the major capsid protein VP2. Based on this information, and on analogy to other autonomous parvoviruses, 24 different peptides were synthesised, coupled to keyhole limpet haemocyanin (KLH) and used to immunise rabbits. Most antisera were able to bind viral protein......The antigenic structure of the capsid proteins of porcine parvovirus (PPV) was investigated. A total of nine linear epitopes were identified by Pepscan using porcine or rabbit anti-PPV antisera. No sites were identified with a panel of neutralising monoclonal antibodies (MAbs). All epitopes were...

  4. Construction of Recombinant Modified Vaccinia Ankara (MVA) Expressing Hepatitis B Virus Surface Antigen

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The T lymphocyte response has been shown to be the determinant in the clearance of many viral infections.Hence, therapeutic vaccine candidates against HBV are designed to enhance this response of the immune system.Vaccinia virus vector-based vaccines have been proposed as excellent candidates to elicit long-term and strong T lymphocyte mediated immune responses. In this study, the recombinant MVA expressing HBV surface antigen has been constructed, which can elicit a potent T cell mediated response. The ELISA results for the surface protein in the medium of the recombinant MVA, strongly indicate that the recombinant virus has been successfully obtained.

  5. High-throughput identification of antigen-specific TCRs by TCR gene capture

    DEFF Research Database (Denmark)

    Linnemann, Carsten; Heemskerk, Bianca; Kvistborg, Pia;

    2013-01-01

    The transfer of T cell receptor (TCR) genes into patient T cells is a promising approach for the treatment of both viral infections and cancer. Although efficient methods exist to identify antibodies for the treatment of these diseases, comparable strategies to identify TCRs have been lacking. We...... the quantitative nature of TCR gene capture, we show the feasibility of identifying antigen-specific TCRs in oligoclonal T cell populations from either human material or TCR-humanized mice. Finally, we demonstrate the ability to identify tumor-reactive TCRs within intratumoral T cell subsets without knowledge...

  6. Novel methods for expression of foreign antigens in live vector vaccines

    Science.gov (United States)

    Wang, Jin Yuan; Harley, Regina H.; Galen, James E.

    2013-01-01

    Bacterial live vector vaccines represent a vaccine development strategy that offers exceptional flexibility. In this approach, genes encoding protective antigens of unrelated bacterial, viral or parasitic pathogens are expressed in an attenuated bacterial vaccine strain that delivers these foreign antigens to the immune system, thereby eliciting relevant immune responses. Rather than expressing these antigens using low copy expression plasmids, here we pursue expression of foreign proteins from the live vector chromosome. Our strategy is designed to compensate for the inherent disadvantage of loss of gene dosage (vs. plasmid-based expression) by integrating antigen-encoding gene cassettes into multiple chromosomal sites already inactivated in an attenuated Salmonella enterica serovar Typhi vaccine candidate. We tested expression of a cassette encoding the green fluorescent protein (GFPuv) integrated separately into native guaBA, htrA or clyA chromosomal loci. Using single integrations, we show that expression levels of GFPuv are significantly affected by the site of integration, regardless of the inclusion of additional strong promoters within the incoming cassette. Using cassettes integrated into both guaBA and htrA, we observe cumulative synthesis levels from two integration sites superior to single integrations. Most importantly, we observe that GFPuv expression increases in a growth phase-dependent manner, suggesting that foreign antigen synthesis may be “tuned” to the physiology of the live vaccine. We expect this novel platform expression technology to prove invaluable in the development of a wide variety of multivalent live vector vaccines, capable of expressing multiple antigens from both chromosomal and plasmid-based expression systems within a single strain. PMID:23406777

  7. Cytotoxicity of tumor antigen specific human T cells is unimpaired by arginine depletion.

    Directory of Open Access Journals (Sweden)

    Markus Munder

    Full Text Available Tumor-growth is often associated with the expansion of myeloid derived suppressor cells that lead to local or systemic arginine depletion via the enzyme arginase. It is generally assumed that this arginine deficiency induces a global shut-down of T cell activation with ensuing tumor immune escape. While the impact of arginine depletion on polyclonal T cell proliferation and cytokine secretion is well documented, its influence on chemotaxis, cytotoxicity and antigen specific activation of human T cells has not been demonstrated so far. We show here that chemotaxis and early calcium signaling of human T cells are unimpaired in the absence of arginine. We then analyzed CD8(+ T cell activation in a tumor peptide as well as a viral peptide antigen specific system: (i CD8(+ T cells with specificity against the MART-1aa26-35*A27L tumor antigen expanded with in vitro generated dendritic cells, and (ii clonal CMV pp65aa495-503 specific T cells and T cells retrovirally transduced with a CMV pp65aa495-503 specific T cell receptor were analyzed. Our data demonstrate that human CD8(+ T cell antigen specific cytotoxicity and perforin secretion are completely preserved in the absence of arginine, while antigen specific proliferation as well as IFN-γ and granzyme B secretion are severely compromised. These novel results highlight the complexity of antigen specific T cell activation and demonstrate that human T cells can preserve important activation-induced effector functions in the context of arginine deficiency.

  8. Antigenic characterization of the human immunodeficiency virus (HIV-1) envelope glycoprotein precursor incorporated into nanodiscs

    Science.gov (United States)

    Witt, Kristen C.; Castillo-Menendez, Luis; Ding, Haitao; Espy, Nicole; Zhang, Shijian; Kappes, John C.; Sodroski, Joseph

    2017-01-01

    The entry of human immunodeficiency virus (HIV-1) into host cells is mediated by the viral envelope glycoproteins (Envs), which are derived by the proteolytic cleavage of a trimeric gp160 Env precursor. The mature Env trimer is a major target for entry inhibitors and vaccine-induced neutralizing antibodies. Env interstrain variability, conformational flexibility and heavy glycosylation contribute to evasion of the host immune response, and create challenges for structural characterization and vaccine development. Here we investigate variables associated with reconstitution of the HIV-1 Env precursor into nanodiscs, nanoscale lipid bilayer discs enclosed by membrane scaffolding proteins. We identified detergents, as well as lipids similar in composition to the viral lipidome, that allowed efficient formation of Env-nanodiscs (Env-NDs). Env-NDs were created with the full-length Env precursor and with an Env precursor with the majority of the cytoplasmic tail intact. The self-association of Env-NDs was decreased by glutaraldehyde crosslinking. The Env-NDs exhibited an antigenic profile expected for the HIV-1 Env precursor. Env-NDs were recognized by broadly neutralizing antibodies. Of note, neutralizing antibody epitopes in the gp41 membrane-proximal external region and in the gp120:gp41 interface were well exposed on Env-NDs compared with Env expressed on cell surfaces. Most Env epitopes recognized by non-neutralizing antibodies were masked on the Env-NDs. This antigenic profile was stable for several days, exhibiting a considerably longer half-life than that of Env solubilized in detergents. Negative selection with weak neutralizing antibodies could be used to improve the antigenic profile of the Env-NDs. Finally, we show that lipid adjuvants can be incorporated into Env-NDs. These results indicate that Env-NDs represent a potentially useful platform for investigating the structural, functional and antigenic properties of the HIV-1 Env trimer in a membrane context

  9. Diagnosis and Control of Viral Diseases of Reproductive Importance: Infectious Bovine Rhinotracheitis and Bovine Viral Diarrhea.

    Science.gov (United States)

    Newcomer, Benjamin W; Givens, Daniel

    2016-07-01

    Both bovine viral diarrhea virus and bovine herpesvirus 1 can have significant negative reproductive impacts on cattle health. Vaccination is the primary control method for the viral pathogens in US cattle herds. Polyvalent, modified-live vaccines are recommended to provide optimal protection against various viral field strains. Of particular importance to bovine viral diarrhea control is the limitation of contact of pregnant cattle with potential viral reservoirs during the critical first 125 days of gestation.

  10. Neural Crest Cells Isolated from the Bone Marrow of Transgenic Mice Express JCV T-Antigen.

    Directory of Open Access Journals (Sweden)

    Jennifer Gordon

    Full Text Available JC virus (JCV, a common human polyomavirus, is the etiological agent of the demyelinating disease, progressive multifocal leukoencephalopathy (PML. In addition to its role in PML, studies have demonstrated the transforming ability of the JCV early protein, T-antigen, and its association with some human cancers. JCV infection occurs in childhood and latent virus is thought to be maintained within the bone marrow, which harbors cells of hematopoietic and non-hematopoietic lineages. Here we show that non-hematopoietic mesenchymal stem cells (MSCs isolated from the bone marrow of JCV T-antigen transgenic mice give rise to JCV T-antigen positive cells when cultured under neural conditions. JCV T-antigen positive cells exhibited neural crest characteristics and demonstrated p75, SOX-10 and nestin positivity. When cultured in conditions typical for mesenchymal cells, a population of T-antigen negative cells, which did not express neural crest markers arose from the MSCs. JCV T-antigen positive cells could be cultured long-term while maintaining their neural crest characteristics. When these cells were induced to differentiate into neural crest derivatives, JCV T-antigen was downregulated in cells differentiating into bone and maintained in glial cells expressing GFAP and S100. We conclude that JCV T-antigen can be stably expressed within a fraction of bone marrow cells differentiating along the neural crest/glial lineage when cultured in vitro. These findings identify a cell population within the bone marrow permissible for JCV early gene expression suggesting the possibility that these cells could support persistent viral infection and thus provide clues toward understanding the role of the bone marrow in JCV latency and reactivation. Further, our data provides an excellent experimental model system for studying the cell-type specificity of JCV T-antigen expression, the role of bone marrow-derived stem cells in the pathogenesis of JCV-related diseases

  11. Microarray-based identification of antigenic variants of foot-and-mouth disease virus: a bioinformatics quality assessment

    Directory of Open Access Journals (Sweden)

    Domingo Esteban

    2006-05-01

    Full Text Available Abstract Background The evolution of viral quasispecies can influence viral pathogenesis and the response to antiviral treatments. Mutant clouds in infected organisms represent the first stage in the genetic and antigenic diversification of RNA viruses, such as foot and mouth disease virus (FMDV, an important animal pathogen. Antigenic variants of FMDV have been classically diagnosed by immunological or RT-PCR-based methods. DNA microarrays are becoming increasingly useful for the analysis of gene expression and single nucleotide polymorphisms (SNPs. Recently, a FMDV microarray was described to detect simultaneously the seven FMDV serotypes. These results encourage the development of new oligonucleotide microarrays to probe the fine genetic and antigenic composition of FMDV for diagnosis, vaccine design, and to gain insight into the molecular epidemiology of this pathogen. Results A FMDV microarray was designed and optimized to detect SNPs at a major antigenic site of the virus. A screening of point mutants of the genomic region encoding antigenic site A of FMDV C-S8c1 was achieved. The hybridization pattern of a mutant includes specific positive and negative signals as well as crosshybridization signals, which are of different intensity depending on the thermodynamic stability of each probe-target pair. Moreover, an array bioinformatic classification method was developed to evaluate the hybridization signals. This statistical analysis shows that the procedure allows a very accurate classification per variant genome. Conclusion A specific approach based on a microarray platform aimed at distinguishing point mutants within an important determinant of antigenicity and host cell tropism, namely the G-H loop of capsid protein VP1, was developed. The procedure is of general applicability as a test for specificity and discriminatory power of microarray-based diagnostic procedures using multiple oligonucleotide probes.

  12. Antigen/Antibody Analyses in Leishmaniasis.

    Science.gov (United States)

    1983-09-01

    antibodies in human sera with antigens of protozoan parasites . It was found that enzyme substrate reactions had distinct advantages over typical...autoradiographic procedures. Analyses of various sera identified a number of antigens of protozoan parasites which may be useful in discriminating infections

  13. Virosomes for antigen and DNA delivery

    NARCIS (Netherlands)

    Daemen, T; de Mare, A; Bungener, L; de Jonge, J; Huckriede, A; Wilschut, J

    2005-01-01

    Specific targeting and delivery as well as the display of antigens on the surface of professional antigen-presenting cells (APCs) are key issues in the design and development of new-generation vaccines aimed at the induction of both humoral and cell-mediated immunity. Prophylactic vaccination agains

  14. Strongly correlated electrostatics of viral genome packaging.

    Science.gov (United States)

    Nguyen, Toan T

    2013-03-01

    The problem of viral packaging (condensation) and ejection from viral capsid in the presence of multivalent counterions is considered. Experiments show divalent counterions strongly influence the amount of DNA ejected from bacteriophage. In this paper, the strong electrostatic interactions between DNA molecules in the presence of multivalent counterions is investigated. It is shown that experiment results agree reasonably well with the phenomenon of DNA reentrant condensation. This phenomenon is known to cause DNA condensation in the presence of tri- or tetra-valent counterions. For divalent counterions, the viral capsid confinement strongly suppresses DNA configurational entropy, therefore the correlation between divalent counterions is strongly enhanced causing similar effect. Computational studies also agree well with theoretical calculations.

  15. V-GAP: Viral genome assembly pipeline

    KAUST Repository

    Nakamura, Yoji

    2015-10-22

    Next-generation sequencing technologies have allowed the rapid determination of the complete genomes of many organisms. Although shotgun sequences from large genome organisms are still difficult to reconstruct perfect contigs each of which represents a full chromosome, those from small genomes have been assembled successfully into a very small number of contigs. In this study, we show that shotgun reads from phage genomes can be reconstructed into a single contig by controlling the number of read sequences used in de novo assembly. We have developed a pipeline to assemble small viral genomes with good reliability using a resampling method from shotgun data. This pipeline, named V-GAP (Viral Genome Assembly Pipeline), will contribute to the rapid genome typing of viruses, which are highly divergent, and thus will meet the increasing need for viral genome comparisons in metagenomic studies.

  16. Hepatitis viral load correlates to glutathione levels.

    Science.gov (United States)

    1998-01-01

    Several recent scientific articles have found a direct correlation between Glutathione levels and viral activity for hepatitis B and C. When viral load increases, Glutathione decreases. Researchers from Germany report that adding NAC (N-acetyl cysteine) to HBV producing cells lines can reduce hepatitis viral load 50 fold. Glutathione is used by the liver to help break down toxins. Patients who have chronic infection for more than 90 days should ask their physicians to check their Glutathione levels. A test kit is available from ImmunoSciences Labs; contact information is included. An amino acid, L-Glutamine, can be used with Alpha Lipoic Acid and NAC to increase Glutathione levels. Chlorophyll also offers benefits to people with hepatitis and other infections. Instructions on how to use a special retention enema containing chlorophyll, water, and apple cider vinegar are provided.

  17. Viral markers in HIV infection and AIDS.

    Science.gov (United States)

    Cunningham, A L; Dwyer, D E; Dowton, D N

    1993-01-01

    Viral and immune markers are used for monitoring either progression of human immunodeficiency virus (HIV) disease or response to antiviral therapy. Ideal properties of viral markers are that they are present in all HIV-infected persons at all stages of disease, that they are related to disease pathogenesis, that they can be easily quantitated, that this quantitation correlates rapidly and predictably with both disease stage and response to antivirals, and that they can be developed into rapid, reproducible automated tests. Currently available viral markers include HIV p24 antigenemia (after acid glycine dissociation), anti-p24 antibody titres, quantitative DNA and RNA polymerase chain reaction performed on cells and plasma, and HIV isolate phenotype. In Australia, these markers have been studied in acute HIV seroconversion, in neonatal infection, in body fluids other than blood, and in monitoring of response to antiviral drug therapy.

  18. Protein antigen delivery by gene gun-mediated epidermal antigen incorporation (EAI).

    Science.gov (United States)

    Scheiblhofer, Sandra; Ritter, Uwe; Thalhamer, Josef; Weiss, Richard

    2013-01-01

    The gene gun technology can not only be employed for efficient transfer of gene vaccines into upper layers of the skin, but also for application of protein antigens. As a tissue rich in professional antigen presenting cells, the skin represents an attractive target for immunizations. In this chapter we present a method for delivery of the model antigen ovalbumin into the skin of mice termed epidermal antigen incorporation and describe in detail how antigen-specific proliferation in draining lymph nodes can be followed by flow cytometry.

  19. Latent Herpes Viral Reactivation in Astronauts

    Science.gov (United States)

    Pierson, D. L.; Mehta, S. K.; Stowe, R.

    2008-01-01

    Latent viruses are ubiquitous and reactivate during stressful periods with and without symptoms. Latent herpes virus reactivation is used as a tool to predict changes in the immune status in astronauts and to evaluate associated health risks. Methods: Viral DNA was detected by real time polymerase chain reaction in saliva and urine from astronauts before, during and after short and long-duration space flights. Results and Discussion: EpsteinBarr virus (EBV), cytomegalovirus (CMV), and varicella zoster virus (VZV) reactivated, and viral DNA was shed in saliva (EBV and VZV) or urine (CMV). EBV levels in saliva during flight were 10fold higher than baseline levels. Elevations in EBV specific CD8+ T-cells, viral antibody titers, and specific cytokines were consistent with viral reactivation. Intracellular levels of cytokines were reduced in EBVspecific Tcells. CMV, rarely present in urine of healthy individuals, was shed in urine of 27% of astronauts during all phases of spaceflight. VZV, not found in saliva of asymptomatic individuals, was found in saliva of 50% of astronauts during spaceflight and 35 days after flight. VZV recovered from astronaut saliva was found to be live, infectious virus. DNA sequencing demonstrated that the VZV recovered from astronauts was from the common European strain of VZV. Elevation of stress hormones accompanied viral reactivation indicating involvement of the hypothalmic-pituitary-adrenal and sympathetic adrenal-medullary axes in the mechanism of viral reactivation in astronauts. A study of 53 shingles patients found that all shingles patients shed VZV DNA in their saliva and the VZV levels correlated with the severity of the disease. Lower VZV levels in shingles patients were similar to those observed in astronauts. We proposed a rapid, simple, and cost-effective assay to detect VZV in saliva of patients with suspected shingles. Early detection of VZV infection allows early medical intervention.

  20. Induction of multi-antigen multi-stage immune responses against Plasmodium falciparum in rhesus monkeys, in the absence of antigen interference, with heterologous DNA prime/poxvirus boost immunization.

    Science.gov (United States)

    Jiang, George; Charoenvit, Yupin; Moreno, Alberto; Baraceros, Maria F; Banania, Glenna; Richie, Nancy; Abot, Steve; Ganeshan, Harini; Fallarme, Victoria; Patterson, Noelle B; Geall, Andrew; Weiss, Walter R; Strobert, Elizabeth; Caro-Aquilar, Ivette; Lanar, David E; Saul, Allan; Martin, Laura B; Gowda, Kalpana; Morrissette, Craig R; Kaslow, David C; Carucci, Daniel J; Galinski, Mary R; Doolan, Denise L

    2007-10-09

    The present study has evaluated the immunogenicity of single or multiple Plasmodium falciparum (Pf) antigens administered in a DNA prime/poxvirus boost regimen with or without the poloxamer CRL1005 in rhesus monkeys. Animals were primed with PfCSP plasmid DNA or a mixture of PfCSP, PfSSP2/TRAP, PfLSA1, PfAMA1 and PfMSP1-42 (CSLAM) DNA vaccines in PBS or formulated with CRL1005, and subsequently boosted with ALVAC-Pf7, a canarypox virus expressing the CSLAM antigens. Cell-mediated immune responses were evaluated by IFN-gamma ELIspot and intracellular cytokine staining, using recombinant proteins and overlapping synthetic peptides. Antigen-specific and parasite-specific antibody responses were evaluated by ELISA and IFAT, respectively. Immune responses to all components of the multi-antigen mixture were demonstrated following immunization with either DNA/PBS or DNA/CRL1005, and no antigen interference was observed in animals receiving CSLAM as compared to PfCSP alone. These data support the down-selection of the CSLAM antigen combination. CRL1005 formulation had no apparent effect on vaccine-induced T cell or antibody responses, either before or after viral boost. In high responder monkeys, CD4+IL-2+ responses were more predominant than CD8+ T cell responses. Furthermore, CD8+ IFN-gamma responses were detected only in the presence of detectable CD4+ T cell responses. Overall, this study demonstrates the potential for multivalent Pf vaccines based on rational antigen selection and combination, and suggests that further formulation development to increase the immunogenicity of DNA encoded antigens is warranted.

  1. Tumor antigens as related to pancreatic cancer.

    Science.gov (United States)

    Chu, T M; Holyoke, E D; Douglass, H O

    1980-01-01

    Data are presented suggesting the presence of pancreas tumor-associated antigens. Slow progress has been made during the past few years in the identification of pancreatic tumor antigens that may be of clinical usefulness and it seems unlikely that many of the practical problems now being faced in identification and isolation of these antigens and in development of a specific, sensitive assay will be solved by conventional immunochemical approaches. The study of antigen and/or antibody purified from immune complexes in the host and the application of leukocyte adherence inhibition techniques to immunodiagnosis of pancreatic cancer are among the new approaches that may provide effective alternatives in the study of pancreatic tumor antigens.

  2. Non-random patterns in viral diversity

    DEFF Research Database (Denmark)

    Anthony, Simon J.; Islam, Ariful; Johnson, Christine;

    2015-01-01

    ) or stochastic (not predictable) processes. We sample macaque faeces across nine sites in Bangladesh and use consensus PCR and sequencing to discover 184 viruses from 14 viral families. We then use network modelling and statistical null-hypothesis testing to show the presence of non-random deterministic patterns...... at different scales, between sites and within individuals. We show that the effects of determinism are not absolute however, as stochastic patterns are also observed. In showing that determinism is an important process in viral community assembly we conclude that it should be possible to forecast changes...

  3. Temporary divergence paralysis in viral meningitis.

    Science.gov (United States)

    Bakker, Stef L M; Gan, Ivan M

    2008-06-01

    A 43-year-old woman who reported diplopia and headache was found to have comitant esotropia at distance fixation and normal alignment at reading distance (divergence paralysis). Eye movement, including abduction, was normal as was the rest of the neurologic examination. Brain MRI was normal. Lumbar puncture showed an elevated opening pressure and a cerebrospinal fluid formula consistent with viral meningitis. The patient was treated with intravenous fluids and analgesics and with a temporary prism to alleviate diplopia. Within 3 weeks, she had fully recovered. This is the first report of divergence palsy in viral meningitis.

  4. Viral diseases in honey bee queens

    DEFF Research Database (Denmark)

    Francis, Roy Mathew

    Honey bees are important insects for human welfare, due to pollination as well as honey production. Viral diseases strongly impact honey bee health, especially since the spread of varroa mites. This dissertation deals with the interactions between honey bees, viruses and varroa mites. A new tool...... was developed to diagnose three viruses in honey bees. Quantitative PCR was used to investigate the distribution of two popular viruses in five different tissues of 86 honey bee queens. Seasonal variation of viral infection in honey bee workers and varroa mites were determined by sampling 23 colonies under...

  5. Arrhythmias in viral myocarditis and pericarditis.

    Science.gov (United States)

    Baksi, A John; Kanaganayagam, G Sunthar; Prasad, Sanjay K

    2015-06-01

    Acute viral myocarditis and acute pericarditis are self-limiting conditions that run a benign course and that may not involve symptoms that lead to medical assessment. However, ventricular arrhythmia is frequent in viral myocarditis. Myocarditis is thought to account for a large proportion of sudden cardiac deaths in young people without prior structural heart disease. Identification of acute myocarditis either with or without pericarditis is therefore important. However, therapeutic interventions are limited and nonspecific. Identifying those at greatest risk of a life-threatening arrhythmia is critical to reducing the mortality. This review summarizes current understanding of this challenging area in which many questions remain.

  6. An Investigation of an Outbreak of Viral Hepatitis B in Modasa Town, Gujarat, India

    Science.gov (United States)

    Patel, Disha A; Gupta, Praveg A; Kinariwala, Deepa M; Shah, Hetal S; Trivedi, Grishma R; Vegad, Mahendra M

    2012-01-01

    Background: Most outbreaks of viral hepatitis in India are caused by hepatitis E. Recently in the year 2009, Modasa town of Sabarkantha district in Gujarat witnessed the outbreak of hepatitis B. Purpose: An attempt was made to study the outbreak clinically and serologically, to estimate the seropositivity of hepatitis B Virus among the cases and their contacts and to know the seroprevalence of hepatitis B envelope antigen (HBeAg) and IgM antibody against hepatitis B core antigen (IgM HBcAb) out of all the Hepatitis B surface Antigen (HBsAg) positive ones. Materials and Methods: Eight hundred and fifty-six (856) cases and 1145 contacts were evaluated for hepatitis B markers namely HBsAg, HBeAg and IgM HBcAb by enzyme-linked immuno Sorbent Assay (ELISA) test. Results: This outbreak of viral hepatitis B in Modasa, Gujarat was most likely due to unsafe injection practices. Evidence in support of this was collected by Government authorities. Most of the patients and approximately 40% of the surveyed population gave history of injections in last 1.5–6 months. Total 664/856 (77.57%) cases and 20/1145 (1.75%) contacts were found to be positive for HBsAg. 53.41% of the positive cases and 52.93% of the positive contacts were HBeAg-positive and thus in a highly infectious stage. Conclusions: Inadequately sterilized needles and syringes are an important cause of transmission of hepatitis B in India. Our data reflects the high positivity rate of a hepatitis B outbreak due to such unethical practices. There is a need to strengthen the routine surveillance system, and to organise a health education campaign targeting all health care workers including private practitioners, especially those working in rural areas, as well as the public at large, to take all possible measures to prevent this often fatal infection. PMID:22529628

  7. The immunogenicity of viral haemorragic septicaemia rhabdovirus (VHSV) DNA vaccines can depend on plasmid regulatory sequences.

    Science.gov (United States)

    Chico, V; Ortega-Villaizan, M; Falco, A; Tafalla, C; Perez, L; Coll, J M; Estepa, A

    2009-03-18

    A plasmid DNA encoding the viral hemorrhagic septicaemia virus (VHSV)-G glycoprotein under the control of 5' sequences (enhancer/promoter sequence plus both non-coding 1st exon and 1st intron sequences) from carp beta-actin gene (pAE6-G(VHSV)) was compared to the vaccine plasmid usually described the gene expression is regulated by the human cytomegalovirus (CMV) immediate-early promoter (pMCV1.4-G(VHSV)). We observed that these two plasmids produced a markedly different profile in the level and time of expression of the encoded-antigen, and this may have a direct effect upon the intensity and suitability of the in vivo immune response. Thus, fish genetic immunisation assays were carried out to study the immune response of both plasmids. A significantly enhanced specific-antibody response against the viral glycoprotein was found in the fish immunised with pAE6-G(VHSV). However, the protective efficacy against VHSV challenge conferred by both plasmids was similar. Later analysis of the transcription profile of a set of representative immune-related genes in the DNA immunized fish suggested that depending on the plasmid-related regulatory sequences controlling its expression, the plasmid might activate distinct patterns of the immune system. All together, the results from this study mainly point out that the selection of a determinate encoded-antigen/vector combination for genetic immunisation is of extraordinary importance in designing optimised DNA vaccines that, when required for inducing protective immune response, could elicit responses biased to antigen-specific antibodies or cytotoxic T cells generation.

  8. An investigation of an outbreak of viral hepatitis B in Modasa town, Gujarat, India

    Directory of Open Access Journals (Sweden)

    Disha A Patel

    2012-01-01

    Full Text Available Background: Most outbreaks of viral hepatitis in India are caused by hepatitis E. Recently in the year 2009, Modasa town of Sabarkantha district in Gujarat witnessed the outbreak of hepatitis B. Purpose: An attempt was made to study the outbreak clinically and serologically, to estimate the seropositivity of hepatitis B Virus among the cases and their contacts and to know the seroprevalence of hepatitis B envelope antigen (HBeAg and IgM antibody against hepatitis B core antigen (IgM HBcAb out of all the Hepatitis B surface Antigen (HBsAg positive ones. Materials and Methods: Eight hundred and fifty-six (856 cases and 1145 contacts were evaluated for hepatitis B markers namely HBsAg, HBeAg and IgM HBcAb by enzyme-linked immuno Sorbent Assay (ELISA test. Results: This outbreak of viral hepatitis B in Modasa, Gujarat was most likely due to unsafe injection practices. Evidence in support of this was collected by Government authorities. Most of the patients and approximately 40% of the surveyed population gave history of injections in last 1.5-6 months. Total 664/856 (77.57% cases and 20/1145 (1.75% contacts were found to be positive for HBsAg. 53.41% of the positive cases and 52.93% of the positive contacts were HBeAg-positive and thus in a highly infectious stage. Conclusions: Inadequately sterilized needles and syringes are an important cause of transmission of hepatitis B in India. Our data reflects the high positivity rate of a hepatitis B outbreak due to such unethical practices. There is a need to strengthen the routine surveillance system, and to organise a health education campaign targeting all health care workers including private practitioners, especially those working in rural areas, as well as the public at large, to take all possible measures to prevent this often fatal infection.

  9. Replicative Homeostasis: A fundamental mechanism mediating selective viral replication and escape mutation

    Directory of Open Access Journals (Sweden)

    Sallie Richard

    2005-02-01

    Full Text Available Abstract Hepatitis C (HCV, hepatitis B (HBV, the human immunodeficiency viruses (HIV, and other viruses that replicate via RNA intermediaries, cause an enormous burden of disease and premature death worldwide. These viruses circulate within infected hosts as vast populations of closely related, but genetically diverse, molecules known as "quasispecies". The mechanism(s by which this extreme genetic and antigenic diversity is stably maintained are unclear, but are fundamental to understanding viral persistence and pathobiology. The persistence of HCV, an RNA virus, is especially problematic and HCV stability, maintained despite rapid genomic mutation, is highly paradoxical. This paper presents the hypothesis, and evidence, that viruses capable of persistent infection autoregulate replication and the likely mechanism mediating autoregulation – Replicative Homeostasis – is described. Replicative homeostasis causes formation of stable, but highly reactive, equilibria that drive quasispecies expansion and generates escape mutation. Replicative homeostasis explains both viral kinetics and the enigma of RNA quasispecies stability and provides a rational, mechanistic basis for all observed viral behaviours and host responses. More importantly, this paradigm has specific therapeutic implication and defines, precisely, new approaches to antiviral therapy. Replicative homeostasis may also modulate cellular gene expression.

  10. Review of Non-Bacterial Infections in Respiratory Medicine: Viral Pneumonia.

    Science.gov (United States)

    Galván, José María; Rajas, Olga; Aspa, Javier

    2015-11-01

    Although bacteria are the main pathogens involved in community-acquired pneumonia, a significant number of community-acquired pneumonia are caused by viruses, either directly or as part of a co-infection. The clinical picture of these different pneumonias can be very similar, but viral infection is more common in the pediatric and geriatric populations, leukocytes are not generally elevated, fever is variable, and upper respiratory tract symptoms often occur; procalcitonin levels are not generally affected. For years, the diagnosis of viral pneumonia was based on cell culture and antigen detection, but since the introduction of polymerase chain reaction techniques in the clinical setting, identification of these pathogens has increased and new microorganisms such as human bocavirus have been discovered. In general, influenza virus type A and syncytial respiratory virus are still the main pathogens involved in this entity. However, in recent years, outbreaks of deadly coronavirus and zoonotic influenza virus have demonstrated the need for constant alert in the face of new emerging pathogens. Neuraminidase inhibitors for viral pneumonia have been shown to reduce transmission in cases of exposure and to improve the clinical progress of patients in intensive care; their use in common infections is not recommended. Ribavirin has been used in children with syncytial respiratory virus, and in immunosuppressed subjects. Apart from these drugs, no antiviral has been shown to be effective. Prevention with anti-influenza virus vaccination and with monoclonal antibodies, in the case of syncytial respiratory virus, may reduce the incidence of pneumonia.

  11. ViralORFeome: an integrated database to generate a versatile collection of viral ORFs.

    Science.gov (United States)

    Pellet, J; Tafforeau, L; Lucas-Hourani, M; Navratil, V; Meyniel, L; Achaz, G; Guironnet-Paquet, A; Aublin-Gex, A; Caignard, G; Cassonnet, P; Chaboud, A; Chantier, T; Deloire, A; Demeret, C; Le Breton, M; Neveu, G; Jacotot, L; Vaglio, P; Delmotte, S; Gautier, C; Combet, C; Deleage, G; Favre, M; Tangy, F; Jacob, Y; Andre, P; Lotteau, V; Rabourdin-Combe, C; Vidalain, P O

    2010-01-01

    Large collections of protein-encoding open reading frames (ORFs) established in a versatile recombination-based cloning system have been instrumental to study protein functions in high-throughput assays. Such 'ORFeome' resources have been developed for several organisms but in virology, plasmid collections covering a significant fraction of the virosphere are still needed. In this perspective, we present ViralORFeome 1.0 (http://www.viralorfeome.com), an open-access database and management system that provides an integrated set of bioinformatic tools to clone viral ORFs in the Gateway(R) system. ViralORFeome provides a convenient interface to navigate through virus genome sequences, to design ORF-specific cloning primers, to validate the sequence of generated constructs and to browse established collections of virus ORFs. Most importantly, ViralORFeome has been designed to manage all possible variants or mutants of a given ORF so that the cloning procedure can be applied to any emerging virus strain. A subset of plasmid constructs generated with ViralORFeome platform has been tested with success for heterologous protein expression in different expression systems at proteome scale. ViralORFeome should provide our community with a framework to establish a large collection of virus ORF clones, an instrumental resource to determine functions, activities and binding partners of viral proteins.

  12. Good Friends, Bad News - Affect and Virality in Twitter

    DEFF Research Database (Denmark)

    Hansen, Lars Kai; Arvidsson, Adam; Nielsen, Finn Årup

    2011-01-01

    The link between affect, defined as the capacity for sentimental arousal on the part of a message, and virality, defined as the probability that it be sent along, is of significant theoretical and practical importance, e.g. for viral marketing. The basic measure of virality in Twitter is the prob......The link between affect, defined as the capacity for sentimental arousal on the part of a message, and virality, defined as the probability that it be sent along, is of significant theoretical and practical importance, e.g. for viral marketing. The basic measure of virality in Twitter...

  13. Acute pancreatitis in acute viral hepatitis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To elucidate the frequency and characteristics of pancreatic involvement in the course of acute (nonfulminant) viral hepatitis.METHODS: We prospectively assessed the pancreatic involvement in patients with acute viral hepatitis who presented with severe abdomimanl pain.RESULTS: We studied 124 patients with acute viral hepatitis, of whom 24 presented with severe abdominal pain. Seven patients (5.65%) were diagnosed to have acute pancreatitis. All were young males. Five patients had pancreatitis in the first week and two in the fourth week after the onset of jaundice. The pancreatitis was mild and all had uneventful recovery from both pancreatitis and hepatitis on conservative treatment.The etiology of pancreatitis was hepatitis E virus in 4,hepatitis A virus in 2, and hepatitis B virus in 1 patient.One patient had biliary sludge along with HEV infection.The abdominal pain of remaining seventeen patients was attributed to stretching of Glisson's capsule.CONCLUSION: Acute pancreatitis occurs in 5.65% of patients with acute viral hepatitis, it is mild and recovers with conservative management.

  14. Meta-analyses on viral hepatitis

    DEFF Research Database (Denmark)

    Gluud, Lise L; Gluud, Christian

    2009-01-01

    This article summarizes the meta-analyses of interventions for viral hepatitis A, B, and C. Some of the interventions assessed are described in small trials with unclear bias control. Other interventions are supported by large, high-quality trials. Although attempts have been made to adjust...

  15. Bovine viral diarrhea virus: biosecurity and control

    Science.gov (United States)

    This paper discusses the recommended procedures involved in setting up biosecurity and control programs designed to limit bovine viral diarrhea virus infections in beef cattle operations. For the purpose of these discussions, a working definition of a biosecurity plan was considered to be an organiz...

  16. Vaccination of cattle against bovine viral diarrhoea

    NARCIS (Netherlands)

    Oirschot, van J.T.; Bruschke, C.J.M.; Rijn, van P.A.

    1999-01-01

    This brief review describes types and quality (efficacy and safety) of bovine viral diarrhoea virus (BVDV) vaccines that are in the market or under development. Both conventional live and killed vaccines are available. The primary aim of vaccination is to prevent congenital infection, but the few va

  17. DETECTION OF THE BOVINE VIRAL DIARRHEA ANTIBODIES

    Directory of Open Access Journals (Sweden)

    I. V. Goraichuk

    2013-06-01

    Full Text Available Bovine viral diarrhea is a widespread infection of cattle that has a wide range of clinical symptoms in domestic and wild ruminants. It is a major problem in cattle and causes significant economic losses in the cattle industry. The virus infects bovines of all ages and causes both immunosuppression and reproductive, respiratory and digestive disorders. Persistently infected cattle are the main factor in transmission of the disease between and among herds. Comparative results of antibodies presence received by two methods of enzymoimmunoassay and virus neutralization test are given in the paper. During the work, 1010 samples of blood serum of cattle from three farms in the Kharkiv region were selected and analyzed. Bovine viral diarrhea virus concerning antibodies were found by enzymoimmunoassay in 704 samples (69.7% using commercial kit and in 690 samples (68.3% using in house method. After results clarification by virus neutralization test, bovine viral diarrhea antibodies were found in 712 samples (70.5%. Immunoenzyme analysis is recommended for mass screening of cattle for viral diarrhea occurrence. The results confirm that the sensitivity immunoenzyme analysis satisfies the requirements of the diagnostic methods. Using the neutralization reaction of viruses as the «gold standard» of serological methods, it is appropriate to clarify the results of immunoenzyme analysis. Since the results contain a signi ficant number of false positive results, it is necessary to carry out comprehensive studies using both serological and molecular genetics methods.

  18. Sanitation of viral haemorrhagic septicaemia (VHS)

    DEFF Research Database (Denmark)

    Olesen, Niels Jørgen

    1998-01-01

    A sanitation programme for stamping-out viral haemorrhagic septicaemia (VHS) was implemented in Denmark in 1965. The programme has resulted in a dramatic reduction in the number of infected rainbow trout farms, from approximate to 400 to 26. The programme is carried out on a voluntary basis...

  19. Viral infections in asthma and COPD.

    Science.gov (United States)

    Matsumoto, Koichiro; Inoue, Hiromasa

    2014-03-01

    Airway viral infections are associated with the pathogenesis of asthma and COPD. It has been argued that respiratory syncytial virus (RSV) infection in infancy is a probable causal factor in the development of pediatric asthma. RSV infections tend to induce Th2-biased immune responses in the host airways. RSV infection, atopy, and low pulmonary function in neonates may work synergistically toward the development of pediatric asthma. Human rhinovirus (HRV) is a representative virus associated with the exacerbation of asthma in both children and adults. Viral infections trigger innate immune responses including granulocytic inflammation and worsen the underlying inflammation due to asthma and COPD. The innate immune responses involve type-I and -III interferon (IFN) production, which plays an important role in anti-viral responses, and the airway epithelia of asthmatics reportedly exhibit defects in the virus-induced IFN responses, which renders these individuals more susceptible to viral infection. A similarly impaired IFN response is seen in COPD, and several investigators propose that latent adenoviral infection may be involved in COPD development. Persistent RSV infections were detected in a sub-population of patients with COPD and were associated with the accelerated decline of lung function. The virus-induced upregulation of co-inhibitory molecules in the airway epithelium partly accounts for the persistent infections. Experimental animal models for virus-asthma/COPD interactions have shed light on the underlying immune mechanisms and are expected to help develop novel approaches to treat respiratory diseases.

  20. Mathematical Modeling of Viral Zoonoses in Wildlife

    OpenAIRE

    2011-01-01

    Zoonoses are a worldwide public health concern, accounting for approximately 75% of human infectious diseases. In addition, zoonoses adversely affect agricultural production and wildlife. We review some mathematical models developed for the study of viral zoonoses in wildlife and identify areas where further modeling efforts are needed.

  1. Viral genome sequencing bt random priming methods

    Science.gov (United States)

    Most emerging health threats are of zoonotic origin. For the overwhelming majority, their causative agents are viruses which include but are not limited to HIV, Influenza, SARS, Ebola, Dengue, and Hantavirus. Of increasing importance therefore is an understanding of the viral diversity to enable b...

  2. Tissue interactions of avian viral attachment proteins

    NARCIS (Netherlands)

    Ambepitiya Wickramasinghe, I.N.

    2015-01-01

    Viruses can infect a wide range of hosts; varying from bacteria and plants to animals and humans. While many viral infections may pass unnoticed, some are of major importance due to their implications on health and welfare of plants, animals and/or humans. In particular, viruses that can infect avia

  3. Viral O-GalNAc peptide epitopes

    DEFF Research Database (Denmark)

    Olofsson, Sigvard; Blixt, Klas Ola; Bergström, Tomas

    2016-01-01

    on a novel three-step procedure that identifies any reactive viral O-glycosyl peptide epitope with respect to (i) relevant peptide sequence, (ii) the reactive glycoform out of several possible glycopeptide isomers of that peptide sequence, and (iii) possibly tolerated carbohydrate or peptide structural...

  4. Sucrose density gradient centrifugation and cross-flow filtration methods for the production of arbovirus antigens inactivated by binary ethylenimine

    Directory of Open Access Journals (Sweden)

    Chuan Teck F

    2004-01-01

    Full Text Available Abstract Background Sucrose density gradient centrifugation and cross-flow filtration methods have been developed and standardised for the safe and reproducible production of inactivated arbovirus antigens which are appropriate for use in diagnostic serological applications. Methods To optimise the maximum titre of growth during the propagation of arboviruses, the multiplicity of infection and choice of cell line were investigated using stocks of Ross River virus and Barmah Forest virus grown in both mosquito and mammalian cell lines. To standardise and improve the efficacy of the inactivation of arboviral suspensions, stocks of Ross River virus, Barmah Forest virus, Japanese encephalitis virus, Murray Valley encephalitis virus and Alfuy virus were chemically inactivated using binary ethylenimine at a final concentration of 3 mM. Aliquots were then taken at hourly intervals and crude inactivation rates were determined for each virus using a plaque assay. To ensure complete inactivation, the same aliquots were each passaged 3 times in Aedes albopictus C6/36 cells and the presence of viral growth was detected using an immunofluorescent assay. For larger quantities of viral suspensions, centrifugation on an isopycnic sucrose density gradient or cross-flow filtration was used to produce concentrated, pure antigens or partially concentrated, semi-purified antigens respectively. Results The results of the propagation experiments suggested that the maximum viral titres obtained for both Ross River virus and Barmah Forest virus were affected by the incubation period and choice of cell line, rather than the use of different multiplicity of infection values. Results of the binary ethylenimine inactivation trial suggested that standardised periods of 5 or 8 hours would be suitable to ensure effective and complete inactivation for a number of different arboviral antigens. Conclusion Two methods used to prepare inactivated arbovirus antigens have been

  5. Combination of small interfering RNAs mediates greater inhibition of human hepatitis B virus replication and antigen expression

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhe; XU Ze-feng; YE Jing-jia; YAO Hang-ping; ZHENG Shu; DING Jia-yi

    2005-01-01

    Objectives: To evaluate the inhibitory effect mediated by combination of small interfering RNAs (siRNAs) targeting different sites of hepatitis B virus (HBV) transcripts on the viral replication and antigen expression in vitro. Methods: (1) Seven siRNAs targeting surface (S), polymerase (P) or precore (PreC) region ofHBV genome were designed and chemically synthesized.(2) HBV-producing HepG2.2.15 cells were treated with or without siRNAs for 72 h. (3) HBsAg and HBeAg in the cell culture medium were detected by enzyme-linked immunoadsorbent assay. (4) Intracellular viral DNA was quantified by real-time PCR(Polymerase Chain Reaction). (5) HBV viral mRNA was reverse transcribed and quantified by real-time PCR. (6) The change of cell cycle and apoptosis was determined by flow cytometry. Results: Our data demonstrated that synthetic small interfering RNAs(siRNAs) targeting S and PreC gene could efficiently and specifically inhibit HBV replication and antigen expression. The expression of HBsAg and HBeAg and the replication of HBV could be specifically inhibited in a dose-dependent manner by siRNAs.Furthermore, our results showed that the combination of siRNAs targeting various regions could inhibit HBV replication and antigen expression in a more efficient way than the use of single siRNA at the same final concentration. No apoptotic change was observed in the cell after siRNA treatment. Conclusion: Our results demonstrated that siRNAs exerted robust and specific inhibition on HBV replication and antigen expression in a cell culture system and combination of siRNAs targeting different regions exhibited more potency.

  6. Antigen clasping by two antigen-binding sites of an exceptionally specific antibody for histone methylation

    Science.gov (United States)

    Hattori, Takamitsu; Lai, Darson; Dementieva, Irina S.; Montaño, Sherwin P.; Kurosawa, Kohei; Zheng, Yupeng; Akin, Louesa R.; Świst-Rosowska, Kalina M.; Grzybowski, Adrian T.; Koide, Akiko; Krajewski, Krzysztof; Strahl, Brian D.; Kelleher, Neil L.; Ruthenburg, Alexander J.; Koide, Shohei

    2016-01-01

    Antibodies have a well-established modular architecture wherein the antigen-binding site residing in the antigen-binding fragment (Fab or Fv) is an autonomous and complete unit for antigen recognition. Here, we describe antibodies departing from this paradigm. We developed recombinant antibodies to trimethylated lysine residues on histone H3, important epigenetic marks and challenging targets for molecular recognition. Quantitative characterization demonstrated their exquisite specificity and high affinity, and they performed well in common epigenetics applications. Surprisingly, crystal structures and biophysical analyses revealed that two antigen-binding sites of these antibodies form a head-to-head dimer and cooperatively recognize the antigen in the dimer interface. This “antigen clasping” produced an expansive interface where trimethylated Lys bound to an unusually extensive aromatic cage in one Fab and the histone N terminus to a pocket in the other, thereby rationalizing the high specificity. A long-neck antibody format with a long linker between the antigen-binding module and the Fc region facilitated antigen clasping and achieved both high specificity and high potency. Antigen clasping substantially expands the paradigm of antibody–antigen recognition and suggests a strategy for developing extremely specific antibodies. PMID:26862167

  7. Sero - Prevalence of Viral Transfusion-transmissible Infections amongst voluntary Blood donors

    Directory of Open Access Journals (Sweden)

    Rashida Elrashid Mohamed Ali

    2016-02-01

    Full Text Available This study aimed to determine the Sero-prevalence of viral transfusion-transmissible Infectious diseases among blood donors, namely immunodeficiency virus, hepatitis B and C transmissible infections (TTIs like HBV, HCV. HIV (Human immune viruses.. sero-prevalence of viral transmissible infections. The donated blood for specific antibodies for infections agents. Can largely reduce the risk of TTIs, virus among blood donors. The study was carried out in the blood bank at Khartoum Teaching Hospital, centre, Sudan. Screening of blood samples for hepatitis B surface Antigen (HBsAg, Human immunodeficiency virus (HIV and hepatitis C virus (HCV Antibodies were done using (ELISA enzyme link immunoassay. The study included (1184 voluntary Blood donors, all were males. The overall prevalence of viral transfusion transmissible Infections were (11.84%. The sero-prevalence for antibody against HIV (6 and hepatitis C Virus was positive in 8 (0.06 and (0.08% donors respectively while HBsAg was detected in 98 (9.8% donors.  situation that need for strict criteria for selection of blood donors and also methods of laboratory assays. Services are high in Sudan due to the endemicity of infections like malaria, nutritional problem and obstetrical emergencies associated with blood loss. Little is known about the level of these infections in Sudan so; this study was conducted to investigate the sero-prevalence of transfusion transmissible viral infectious diseases in particular human B and hepatitis Immunodeficiency, hepatitis C viruses. The mode of transmission for HIV, HBV and HCV is the same and includes unsafe Sexual sharp materials Contact, using contaminated with body fluid, mother to Child and transfusion of blood and blood Products.

  8. Viral perturbations of host networks reflect disease etiology.

    Directory of Open Access Journals (Sweden)

    Natali Gulbahce

    Full Text Available Many human diseases, arising from mutations of disease susceptibility genes (genetic diseases, are also associated with viral infections (virally implicated diseases, either in a directly causal manner or by indirect associations. Here we examine whether viral perturbations of host interactome may underlie such virally implicated disease relationships. Using as models two different human viruses, Epstein-Barr virus (EBV and human papillomavirus (HPV, we find that host targets of viral proteins reside in network proximity to products of disease susceptibility genes. Expression changes in virally implicated disease tissues and comorbidity patterns cluster significantly in the network vicinity of viral targets. The topological proximity found between cellular targets of viral proteins and disease genes was exploited to uncover a novel pathway linking HPV to Fanconi anemia.

  9. Functional Specialty of CD40 and Dendritic Cell Surface Lectins for Exogenous Antigen Presentation to CD8(+) and CD4(+) T Cells.

    Science.gov (United States)

    Yin, Wenjie; Gorvel, Laurent; Zurawski, Sandra; Li, Dapeng; Ni, Ling; Duluc, Dorothée; Upchurch, Katherine; Kim, JongRok; Gu, Chao; Ouedraogo, Richard; Wang, Zhiqing; Xue, Yaming; Joo, HyeMee; Gorvel, Jean-Pierre; Zurawski, Gerard; Oh, SangKon

    2016-03-01

    Dendritic cells (DCs) are major antigen-presenting cells that can efficiently prime and cross-prime antigen-specific T cells. Delivering antigen to DCs via surface receptors is thus an appealing strategy to evoke cellular immunity. Nonetheless, which DC surface receptor to target to yield the optimal CD8(+) and CD4(+) T cell responses remains elusive. Herein, we report the superiority of CD40 over 9 different lectins and scavenger receptors at evoking antigen-specific CD8(+) T cell responses. However, lectins (e.g., LOX-1 and Dectin-1) were more efficient than CD40 at eliciting CD4(+) T cell responses. Common and distinct patterns of subcellular and intracellular localization of receptor-bound αCD40, αLOX-1 and αDectin-1 further support their functional specialization at enhancing antigen presentation to either CD8(+) or CD4(+) T cells. Lastly, we demonstrate that antigen targeting to CD40 can evoke potent antigen-specific CD8(+) T cell responses in human CD40 transgenic mice. This study provides fundamental information for the rational design of vaccines against cancers and viral infections.

  10. Kinetics of viral shedding provide insights into the epidemiology of viral hemorrhagic septicemia in Pacific herring

    Science.gov (United States)

    Hershberger, Paul K.; Gregg, Jacob L.; Winton, James R.; Grady, Courtney; Collins, Rachael

    2010-01-01

    Losses from infectious diseases are an important component of natural mortality among marine fish species, but factors controlling the ecology of these diseases and their potential responses to anthropogenic changes are poorly understood. We used viral hemorrhagic septicemia virus (VHSV) and a laboratory stock of Pacific herring Clupea pallasii to investigate the kinetics of viral shedding and its effect on disease transmission and host mortality. Outbreaks of acute disease, accompanied by mortality and viral shedding, were initiated after waterborne exposure of herring to concentrations of VHSV as low as 101 plaque-forming units (pfu) ml–1. Shed virus in flow-through tanks was first detected 4 to 5 d post-exposure, peaked after 6 to 10 d, and was no longer detected after 16 d. Shedding rates, calculated from density, flow and waterborne virus titer reached 1.8 to 5.0 × 108 pfu fish–1 d–1. Onset of viral shedding was dose-dependent and preceded initial mortality by 2 d. At 21 d, cumulative mortality in treatment groups ranged from 81 to 100% and was dependent not on challenge dose, but on the kinetics and level of viral shedding by infected fish in the tank. Possible consequences of the viral shedding and disease kinetics are discussed in the context of epizootic initiation and perpetuation among populations of wild Pacific herring.

  11. In vivo targeting of antigens to maturing dendritic cells via the DEC-205 receptor improves T cell vaccination.

    Science.gov (United States)

    Bonifaz, Laura C; Bonnyay, David P; Charalambous, Anna; Darguste, Dara I; Fujii, Shin-Ichiro; Soares, Helena; Brimnes, Marie K; Moltedo, Bruno; Moran, Thomas M; Steinman, Ralph M

    2004-03-15

    The prevention and treatment of prevalent infectious diseases and tumors should benefit from improvements in the induction of antigen-specific T cell immunity. To assess the potential of antigen targeting to dendritic cells to improve immunity, we incorporated ovalbumin protein into a monoclonal antibody to the DEC-205 receptor, an endocytic receptor that is abundant on these cells in lymphoid tissues. Simultaneously, we injected agonistic alpha-CD40 antibody to mature the dendritic cells. We found that a single low dose of antibody-conjugated ovalbumin initiated immunity from the naive CD4+ and CD8+ T cell repertoire. Unexpectedly, the alphaDEC-205 antigen conjugates, given s.c., targeted to dendritic cells systemically and for long periods, and ovalbumin peptide was presented on MHC class I for 2 weeks. This was associated with stronger CD8+ T cell-mediated immunity relative to other forms of antigen delivery, even when the latter was given at a thousand times higher doses. In parallel, the mice showed enhanced resistance to an established rapidly growing tumor and to viral infection at a mucosal site. By better harnessing the immunizing functions of maturing dendritic cells, antibody-mediated antigen targeting via the DEC-205 receptor increases the efficiency of vaccination for T cell immunity, including systemic and mucosal resistance in disease models.

  12. In Vivo Targeting of Antigens to Maturing Dendritic Cells via the DEC-205 Receptor Improves T Cell Vaccination

    Science.gov (United States)

    Bonifaz, Laura C.; Bonnyay, David P.; Charalambous, Anna; Darguste, Dara I.; Fujii, Shin-Ichiro; Soares, Helena; Brimnes, Marie K.; Moltedo, Bruno; Moran, Thomas M.; Steinman, Ralph M.

    2004-01-01

    The prevention and treatment of prevalent infectious diseases and tumors should benefit from improvements in the induction of antigen-specific T cell immunity. To assess the potential of antigen targeting to dendritic cells to improve immunity, we incorporated ovalbumin protein into a monoclonal antibody to the DEC-205 receptor, an endocytic receptor that is abundant on these cells in lymphoid tissues. Simultaneously, we injected agonistic α-CD40 antibody to mature the dendritic cells. We found that a single low dose of antibody-conjugated ovalbumin initiated immunity from the naive CD4+ and CD8+ T cell repertoire. Unexpectedly, the αDEC-205 antigen conjugates, given s.c., targeted to dendritic cells systemically and for long periods, and ovalbumin peptide was presented on MHC class I for 2 weeks. This was associated with stronger CD8+ T cell–mediated immunity relative to other forms of antigen delivery, even when the latter was given at a thousand times higher doses. In parallel, the mice showed enhanced resistance to an established rapidly growing tumor and to viral infection at a mucosal site. By better harnessing the immunizing functions of maturing dendritic cells, antibody-mediated antigen targeting via the DEC-205 receptor increases the efficiency of vaccination for T cell immunity, including systemic and mucosal resistance in disease models. PMID:15024047

  13. Composition of inflammatory infiltrate and its correlation with HBV/HCV antigen expression

    Institute of Scientific and Technical Information of China (English)

    Bozena Walewska-Zielecka; Kazimierz Madalinski; Joanna Jablonska; Paulina Godzik; Joanna Cielecka-Kuszyk; Bogumila Litwinska

    2008-01-01

    AIM: To study the composition of liver inflammatory infiltrate in biopsy material from patients chronically infected with hepatotropic viruses and to evaluate the correlation of inflammatory infiltrate with hepatitis B virus (HBV) and hepatitis C virus (HCV) viral antigen expression in chronic B and C hepatitis.METHODS: The phenotype of inflammatory cells was evaluated by the EnVision system, using a panel of monoclonal antibodies. HBV and HCV antigens were detected with the use of monoclonal anti-HBs, poly-clonal anti-HBc and anti-HCV antibodies, respectively.RESULTS: The cellular composition of liver inflammatory infiltrate was similar in the patients with B and C hepatitis: ~50%-60% of cells were T helper lymphooltes. Approximately 25% were T cytotoxic lymphocytes; B lymphocytes comprised 15% of inflammatory infiltrate; other cells, including NK, totalled 10%. Expression of HLA antigens paralleled inflammatory activity. Portal lymphadenoplasia was found more often in hepatitis C (54.5%) than in hepatitis B (30.6%). Expression of HB-cAg was found more often in chronic B hepatitis of moderate or severe activity. Overall inflammatory activity in HBV-infected cases did not correlate with the intensity of HBsAg expression in hepatooltes. Inflammatory infiltrates accompanied the focal expression of HCV anti-gens. A direct correlation between antigen expression and inflammatory reaction in situ was noted more often in hepatitis C than B.CONCLUSION: Irrespective of the etiology and activity of hepatitis, components of the inflammatory infiltrate in liver were similar. Overall inflammatory activity did not correlate with the expression of HBsAg and HCVAg; HBcAg expression, however, accompanied chronic hepatitis B of moderate and severe activity.

  14. The evolution of bovine viral diarrhea: a review

    OpenAIRE

    Goens, Denise

    2002-01-01

    The economic importance of bovine viral diarrhea is increasing with the emergence of seemingly more virulent viruses, as evidenced by outbreaks of hemorrhagic syndrome and severe acute bovine viral diarrhea beginning in the 1980s and 1990s. It appears that evolutionary changes in bovine viral diarrhea virus were responsible for these outbreaks. The genetic properties of the classical bovine viral diarrhea virus that contribute to the basis of current diagnostic tests, vaccines, and our unders...

  15. Viral DNA in horses infected with equine infectious anemia virus.

    OpenAIRE

    Rice, N R; Lequarré, Anne-Sophie; Casey, J W; Lahn, S; Stephens, R. M.; Edwards, J.

    1989-01-01

    The amount and distribution of viral DNA were established in a horse acutely infected with the Wyoming strain of equine infectious anemia virus (EIAV). The highest concentration of viral DNA were found in the liver, lymph nodes, bone marrow, and spleen. The kidney, choroid plexus, and peripheral blood leukocytes also contained viral DNA, but at a lower level. It is estimated that at day 16 postinoculation, almost all of the viral DNA was located in the tissues, with the liver alone containing...

  16. Antigen-specific memory B cell development.

    Science.gov (United States)

    McHeyzer-Williams, Louise J; McHeyzer-Williams, Michael G

    2005-01-01

    Helper T (Th) cell-regulated B cell immunity progresses in an ordered cascade of cellular development that culminates in the production of antigen-specific memory B cells. The recognition of peptide MHC class II complexes on activated antigen-presenting cells is critical for effective Th cell selection, clonal expansion, and effector Th cell function development (Phase I). Cognate effector Th cell-B cell interactions then promote the development of either short-lived plasma cells (PCs) or germinal centers (GCs) (Phase II). These GCs expand, diversify, and select high-affinity variants of antigen-specific B cells for entry into the long-lived memory B cell compartment (Phase III). Upon antigen rechallenge, memory B cells rapidly expand and differentiate into PCs under the cognate control of memory Th cells (Phase IV). We review the cellular and molecular regulators of this dynamic process with emphasis on the multiple memory B cell fates that develop in vivo.

  17. Platelet antigens and antibodies. Literature review

    Directory of Open Access Journals (Sweden)

    N. V. Mineeva

    2014-07-01

    Full Text Available Platelet antigens structure, role of platelet antibodies in the pathogenesis of various clinical conditions, characteristic of modern antibodies detection methods are presented in this article.

  18. Platelet antigens and antibodies. Literature review

    Directory of Open Access Journals (Sweden)

    N. V. Mineeva

    2013-01-01

    Full Text Available Platelet antigens structure, role of platelet antibodies in the pathogenesis of various clinical conditions, characteristic of modern antibodies detection methods are presented in this article.

  19. Evaluation of long-term antibody responses to two inactivated bovine viral diarrhoea virus (BVDV) vaccines.

    Science.gov (United States)

    González, Ana M; Arnaiz, Ignacio; Yus, Eduardo; Eiras, Carmen; Sanjuán, María; Diéguez, Francisco J

    2014-03-01

    The aim of the present study was to determine the serological response of heifers after vaccination with two inactivated bovine viral diarrhoea virus (BVDV) vaccines by means of various ELISA tests. Three dairy farms were selected from the Galicia region of Spain. In each herd, a batch of heifers to be vaccinated for the first time was selected and followed for 15 months. Heifers from farm 1 (n=25) were vaccinated with Vaccine A, whereas heifers from farm 2 (n=16) were vaccinated with Vaccine B. Heifers from farm 3 (n=17), where no BVDV vaccines were used, acted as controls. Blood samples were analyzed periodically for BVDV antibodies, using five commercial ELISAs, based on BVDV p80 antigen or whole virus. At the end of the study, none of the animals vaccinated with Vaccine A seroconverted according to p80 antibody status, whereas up to 80% tested positive by ELISA against whole virus antigen. For the animals vaccinated with Vaccine B, 2/16 animals seroconverted according to p80 antibody ELISAs, whereas all had seroconverted according to the ELISA against whole virus antigen. In most cases, based on the use of ELISAs to detect specific antibodies against the p80 protein, at 15 months post-vaccination with inactivated BVDV vaccines the responses did not seem to interfere with detection of antibody to BVDV infection. However, the finding of a small proportion of vaccinated animals seropositive against BVDV p80 antigen suggests that antibodies that interfere with diagnosis of BVDV infection within the herd could exist, even when using p80 ELISAs.

  20. MAGE-A Antigens and Cancer Immunotherapy

    Science.gov (United States)

    Zajac, Paul; Schultz-Thater, Elke; Tornillo, Luigi; Sadowski, Charlotte; Trella, Emanuele; Mengus, Chantal; Iezzi, Giandomenica; Spagnoli, Giulio C.

    2017-01-01

    MAGE-A antigens are expressed in a variety of cancers of diverse histological origin and germinal cells. Due to their relatively high tumor specificity, they represent attractive targets for active specific and adoptive cancer immunotherapies. Here, we (i) review past and ongoing clinical studies targeting these antigens, (ii) analyze advantages and disadvantages of different therapeutic approaches, and (iii) discuss possible improvements in MAGE-A-specific immunotherapies. PMID:28337438

  1. Anti-Viral Prophylaxis Target Product Profile Guidelines

    Science.gov (United States)

    2009-02-24

    or emerging viral diseases, as medical countermeasures to viral biowarfare threats are limited. • Objective: avian influenza (oseltamavir) • Threshold...to viral biowarfare threats are limited. • Objective: hepatitis A (immune serum globulin) • Threshold: HIV postexposure prophylaxis). Route of...administration: • Objective: modeled from influenza (oseltamavir); • Threshold modeled from hepatitis A, rabies (immune serum globulin, rabies immune

  2. "Viral déjà vu" elicits organ-specific immune disease independent of reactivity to self.

    Science.gov (United States)

    Merkler, Doron; Horvath, Edit; Bruck, Wolfgang; Zinkernagel, Rolf M; Del la Torre, Juan Carlos; Pinschewer, Daniel D

    2006-05-01

    Autoimmune diseases are often precipitated by viral infections. Yet our current understanding fails to explain how viruses trigger organ-specific autoimmunity despite thymic tolerance extending to many non-lymphohematopoietic self antigens. Additionally, a key epidemiological finding needs to be explained: In genetically susceptible individuals, early childhood infections seem to predispose them to multiple sclerosis (MS) or type 1 diabetes years or even decades before clinical onset. In the present work, we show that the innate immune system of neonatal mice was sufficient to eliminate an attenuated lymphocytic choriomeningitis virus (LCMV) from most tissues except for the CNS, where the virus persisted in neurons (predisposing virus). Virus-specific cytotoxic T cells (CTLs) were neither deleted nor sufficiently primed to cause disease, but they were efficiently triggered in adulthood upon WT LCMV infection (precipitating virus). This defined sequence of viral infections caused severe CNS inflammation that was histomorphologically reminiscent of rasmussen encephalitis, a fatal human autoimmune disease. Yet disease in mice was mediated by antiviral CTLs targeting an epitope shared by the precipitating virus and the predisposing virus persisting in neurons (déjà vu). Thus the concept of "viral déjà vu" demonstrates how 2 related but independently encountered viral infections can cause organ-specific immune disease without molecular mimicry of self and without breaking self tolerance.

  3. Lamivudine plus adefovir is a good option for chronic hepatitis B patients with viral relapse after cessation of lamivudine treatment

    Directory of Open Access Journals (Sweden)

    Zhang Yong

    2011-08-01

    Full Text Available Abstract Aim Currently, there is no consensus on the retreatment recommendation of chronic hepatitis B (CHB patients with viral rebound after cessation of treatment. In the search of reasonable treatment, we compared the efficacy and safety of adefovir (ADV plus lamivudine (LAM and LAM alone for the retreatment of patients with viral relapse but without genotypic resistance after cessation of LAM. Methods This is a prospective controlled study, and a total of 53 hepatitis B e antigen (HBeAg-positive patients with viral rebound but without resistance were received either LAM plus ADV or LAM alone treatment. Results After 1-year treatment, more patients who received LAM plus ADV than those who received LAM alone had ALT normalization (84% versus 53.6%, P = 0.018 or HBV DNA levels below 1000 copies/mL (80% versus 42.9%, P Conclusions Patients treated with LAM plus ADV exhibited significantly greater virological, biochemical and serological responses compared with LAM alone. These data suggested that combination of LAM plus ADV would be a good option for the retreatment of CHB patients with viral relapse after cessation of LAM.

  4. Development of influenza A(H7N9) candidate vaccine viruses with improved hemagglutinin antigen yield in eggs

    Science.gov (United States)

    Ridenour, Callie; Johnson, Adam; Winne, Emily; Hossain, Jaber; Mateu-Petit, Guaniri; Balish, Amanda; Santana, Wanda; Kim, Taejoong; Davis, Charles; Cox, Nancy J; Barr, John R; Donis, Ruben O; Villanueva, Julie; Williams, Tracie L; Chen, Li-Mei

    2015-01-01

    Background The emergence of avian influenza A(H7N9) virus in poultry causing zoonotic human infections was reported on March 31, 2013. Development of A(H7N9) candidate vaccine viruses (CVV) for pandemic preparedness purposes was initiated without delay. Candidate vaccine viruses were derived by reverse genetics using the internal genes of A/Puerto/Rico/8/34 (PR8). The resulting A(H7N9) CVVs needed improvement because they had titers and antigen yields that were suboptimal for vaccine manufacturing in eggs, especially in a pandemic situation. Methods Two CVVs derived by reverse genetics were serially passaged in embryonated eggs to improve the hemagglutinin (HA) antigen yield. The total viral protein and HA antigen yields of six egg-passaged CVVs were determined by the BCA assay and isotope dilution mass spectrometry (IDMS) analysis, respectively. CVVs were antigenically characterized by hemagglutination inhibition (HI) assays with ferret antisera. Results Improvement of total viral protein yield was observed for the six egg-passaged CVVs; HA quantification by IDMS indicated approximately a twofold increase in yield of several egg-passaged viruses as compared to that of the parental CVV. Several different amino acid substitutions were identified in the HA of all viruses after serial passage. However, HI tests indicated that the antigenic properties of two CVVs remained unchanged. Conclusions If influenza A(H7N9) viruses were to acquire sustained human-to-human transmissibility, the improved HA yield of the egg-passaged CVVs generated in this study could expedite vaccine manufacturing for pandemic mitigation. PMID:25962412

  5. Presentation of antigen by B cells subsets. Pt. 2. The role of CD5 B cells in the presentation of antigen to antigen-specific T cells

    Energy Technology Data Exchange (ETDEWEB)

    Zimecki, Michal [Polish Academy of Sciences, Wroclaw (Poland). Institute of Immunology and Experimental Therapy; Kapp, Judith A. [Emory Univ., Atlanta, GA (United States). School of Medicine

    1994-12-31

    We demonstrate that peritoneal B cells have a much higher ability to present antigen to antigen-specific T cell lines splenic B cells. Presentation of antigen by B cells is abrogated or drastically reduced after removal of Lyb-5{sup +} cells from the population of splenic or peritoneal B cells. Peritoneal B cells, precultured for 7 days prior to the antigen presentation assay, retain their antigen presenting cell (APC) function. Enrichment for CD5{sup +} cells in the peritoneal B cell population results in a more effective antigen presentation. Lastly, stimulation of B cells via CD5 antigen, by treatment of cells with anti-CD5 antibodies or cross-linking of CD5 receptors, enhances APC function of these cells. The results indicate, both indirectly and directly, that CD5{sup +} B cells play a predominant role in the presentation of conventional antigens to antigen-specific T cells. (author). 30 refs, 6 tabs.

  6. CXC chemokine ligand 10 controls viral infection in the central nervous system: evidence for a role in innate immune response through recruitment and activation of natural killer cells.

    Science.gov (United States)

    Trifilo, Matthew J; Montalto-Morrison, Cynthia; Stiles, Linda N; Hurst, Kelley R; Hardison, Jenny L; Manning, Jerry E; Masters, Paul S; Lane, Thomas E

    2004-01-01

    How chemokines shape the immune response to viral infection of the central nervous system (CNS) has largely been considered within the context of recruitment and activation of antigen-specific lymphocytes. However, chemokines are expressed early following viral infection, suggesting an important role in coordinating innate immune responses. Herein, we evaluated the contributions of CXC chemokine ligand 10 (CXCL10) in promoting innate defense mechanisms following coronavirus infection of the CNS. Intracerebral infection of RAG1(-/-) mice with a recombinant CXCL10-expressing murine coronavirus (mouse hepatitis virus) resulted in protection from disease and increased survival that correlated with a significant increase in recruitment and activation of natural killer (NK) cells within the CNS. Accumulation of NK cells resulted in a reduction in viral titers that was dependent on gamma interferon secretion. These results indicate that CXCL10 expression plays a pivotal role in defense following coronavirus infection of the CNS by enhancing innate immune responses.

  7. From Viral genome to specific peptide epitopes - Methods for identifying porcine T cell epitopes based on in silico predictions, in vitro identification and ex vivo verification

    DEFF Research Database (Denmark)

    Pedersen, Lasse Eggers; Rasmussen, Michael; Harndahl, Mikkel

    immunity during viral infections and disease. Here we combine the ability of complete nonamer peptide based binding matrices for three different SLA proteins to predict good candidates for peptide-SLA (pSLA) binding with that of an online available algorithm, NetMHCpan. Further we analyze the correlation......The affinity for and stability of peptides bound by major histocompatibility complex (MHC) class I molecules are instrumental factors in presentation of viral epitopes to cytotoxic T lymphocytes (CTLs). In swine, such peptide presentations by swine leukocyte antigens (SLA) are crucial for swine...... can be identified within a given viral genome, along with the elimination of hundreds, or even thousands, of peptide sequences, which are not likely to be bound. Applying these methods can save enormous amounts of time and costs of epitope discovery studies and MHC binding analysis not only in swine...

  8. Memory inflation during chronic viral infection is maintained by continuous production of short-lived, functional T cells.

    Science.gov (United States)

    Snyder, Christopher M; Cho, Kathy S; Bonnett, Elizabeth L; van Dommelen, Serani; Shellam, Geoffrey R; Hill, Ann B

    2008-10-17

    During persistent murine cytomegalovirus (MCMV) infection, the T cell response is maintained at extremely high intensity for the life of the host. These cells closely resemble human CMV-specific cells, which compose a major component of the peripheral T cell compartment in most people. Despite a phenotype that suggests extensive antigen-driven differentiation, MCMV-specific T cells remain functional and respond vigorously to viral challenge. We hypothesized that a low rate of antigen-driven proliferation would account for the maintenance of this population. Instead, we found that most of these cells divided only sporadically in chronically infected hosts and had a short half-life in circulation. The overall population was supported, at least in part, by memory T cells primed early in infection, as well as by recruitment of naive T cells at late times. Thus, these data show that memory inflation is maintained by a continuous replacement of short-lived, functional cells during chronic MCMV infection.

  9. Variable domain antibodies specific for viral hemorrhagic septicemia virus (VHSV) selected from a randomized IgNAR phage display library.

    Science.gov (United States)

    Ohtani, Maki; Hikima, Jun-ichi; Jung, Tae-Sung; Kondo, Hidehiro; Hirono, Ikuo; Takeyama, Haruko; Aoki, Takashi

    2013-02-01

    Phage display libraries are used to screen for nucleotide sequences that encode immunoglobulin variable (V) regions that are specific for a target antigen. We previously constructed an immunoglobulin new antigen receptor (IgNAR) phage display library. Here we used this library to obtain an IgNAR V region that is specific for viral hemorrhagic septicemia virus (VHSV). A phage clone (clone 653) was found to be specific for VHSV by the biopanning method. The V region of clone 653 was used to construct a 6 × His tagged recombinant IgNAR-653 V protein (rIgNAR-653) using the Escherichia coli pET system. The rIgNAR-653 protein bound specifically to VHSV, confirming its activity.

  10. HCV核心抗原动态监测抗HCV疗效的临床研究%Monitoring the clinical efficacy of antiviral therapy by using the HCV core antigen and HCV PCR assays

    Institute of Scientific and Technical Information of China (English)

    吴文娟; 张云智; 靳宏; 刘袁媛; 胡芸文; 张友祥

    2011-01-01

    Objective To evaluate the performance of Hepatitis C virus (HCV) core antigen and HCV RNA PCR in the determining of the efficacy of HCV antiviral therapy in patients infected with HCV. Methods HCV core antigen and HCV RNA were measured in sera of 35 chronic HCV infected Chinese patients. Concentrations of HCV core antigen and HCV RNA were analyzed at 5 time points before, during and at the end of antiviral therapy. Results This study showed that the HCV core antigen and HCV RNA concentrations in 35 HCV patients were significantly correlated. Decrease of HCV core antigen and HCV RNA concentrations at the 4th, 12th,24th and 48th week were observed during the antiviral therapy. However,HCV core antigen levels at week 12 and 24 of therapy were significantly lower than those at week 4 (P 0. 05). HCV core antigen testing may be advantageous in some cases,in particular,the low levels of HCV core antigen at week 4 may be predictive of satisfactory outcome of treatment. Conclusions HCV core antigen represents a stable and sensitive marker of viral replication and could be used to monitor the clinical efficacy of HCV antiviral therapy.

  11. Multiplexing Short Primers for Viral Family PCR

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, S N; Hiddessen, A L; Hara, C A; Williams, P L; Wagner, M; Colston, B W

    2008-06-26

    We describe a Multiplex Primer Prediction (MPP) algorithm to build multiplex compatible primer sets for large, diverse, and unalignable sets of target sequences. The MPP algorithm is scalable to larger target sets than other available software, and it does not require a multiple sequence alignment. We applied it to questions in viral detection, and demonstrated that there are no universally conserved priming sequences among viruses and that it could require an unfeasibly large number of primers ({approx}3700 18-mers or {approx}2000 10-mers) to generate amplicons from all sequenced viruses. We then designed primer sets separately for each viral family, and for several diverse species such as foot-and-mouth disease virus, hemagglutinin and neuraminidase segments of influenza A virus, Norwalk virus, and HIV-1.

  12. Polymerase Chain Reaction on a Viral Nanoparticle.

    Science.gov (United States)

    Carr-Smith, James; Pacheco-Gómez, Raúl; Little, Haydn A; Hicks, Matthew R; Sandhu, Sandeep; Steinke, Nadja; Smith, David J; Rodger, Alison; Goodchild, Sarah A; Lukaszewski, Roman A; Tucker, James H R; Dafforn, Timothy R

    2015-12-18

    The field of synthetic biology includes studies that aim to develop new materials and devices from biomolecules. In recent years, much work has been carried out using a range of biomolecular chassis including α-helical coiled coils, β-sheet amyloids and even viral particles. In this work, we show how hybrid bionanoparticles can be produced from a viral M13 bacteriophage scaffold through conjugation with DNA primers that can template a polymerase chain reaction (PCR). This unprecedented example of a PCR on a virus particle has been studied by flow aligned linear dichroism spectroscopy, which gives information on the structure of the product as well as a new protototype methodology for DNA detection. We propose that this demonstration of PCR on the surface of a bionanoparticle is a useful addition to ways in which hybrid assemblies may be constructed using synthetic biology.

  13. Zoonotic Viral Deseases and Virus Discovery

    DEFF Research Database (Denmark)

    Nielsen, Sandra Cathrine Abel

    Viruses are the most abundant organisms on earth and are ubiquitous in all environments where life is present. They are capable of infecting all cellular forms of life, sometimes causing disease in the infected host. This thesis is broadly divided into two main sections with three projects...... representing work on viruses that are transmitted between humans and animals, and 3 three projects describing the search for (novel) viruses or a viral association in human diseases with no known cause. Common for all projects was the need for employing a range of different molecular tools examples...... program of wildlife, and with the purpose of preventing the next disease emerging from these animals. Numerous viruses were detected of which many were novel variants, thus reaffirming the notion that attention should be focused at these animals. Near-complete viral genome sequencing was performed...

  14. Infección viral respiratoria nosocomial

    Directory of Open Access Journals (Sweden)

    G.A. March Rosselló

    2014-08-01

    Full Text Available Las infecciones virales nosocomiales han sido objeto de pocos estudios. En este contexto, el objetivo de este trabajo es revisar los datos epidemiológicos y terapéuticos publicados sobre los principales agentes virales productores de infección nosocomial respiratoria. De este modo se pretende ampliar el conocimiento sobre el comportamiento de estos agentes en las infecciones nosocomiales y proporcionar información para mejorar la aplicación de las medidas de prevención. De manera pormenorizada se exponen conceptos relativos a los mimivirus, virus herpes simple, virus varicela-zóster, citomegalovirus, virus respiratorio sincitial, virus parainfluenza, virus de la gripe, adenovirus, metapneumovirus y virus del sarampión.

  15. Statistical Mechanics and Thermodynamics of Viral Evolution

    Science.gov (United States)

    Jones, Barbara; Kaufman, James

    Using methods drawn from physics we study the life cycle of viruses. We analyze a model of viral infection and evolution using the ``grand canonical ensemble'' and formalisms from statistical mechanics and thermodynamics. Using this approach we determine possible genetic states of a model virus and host as a function of two independent pressures-immune response and system temperature. We show the system has a real thermodynamic temperature, and discover a new phase transition between a positive temperature regime of normal replication and a negative temperature ``disordered'' phase of the virus. We distinguish this from previous observations of a phase transition that arises as a function of mutation rate. From an evolutionary biology point of view, at steady state the viruses naturally evolve to distinct quasispecies. The approach used here could be refined to apply to real biological systems, perhaps providing insight into immune escape, the emergence of novel pathogens and other results of viral evolution.

  16. Lytic to temperate switching of viral communities

    Science.gov (United States)

    Knowles, B.; Silveira, C. B.; Bailey, B. A.; Barott, K.; Cantu, V. A.; Cobián-Güemes, A. G.; Coutinho, F. H.; Dinsdale, E. A.; Felts, B.; Furby, K. A.; George, E. E.; Green, K. T.; Gregoracci, G. B.; Haas, A. F.; Haggerty, J. M.; Hester, E. R.; Hisakawa, N.; Kelly, L. W.; Lim, Y. W.; Little, M.; Luque, A.; McDole-Somera, T.; McNair, K.; de Oliveira, L. S.; Quistad, S. D.; Robinett, N. L.; Sala, E.; Salamon, P.; Sanchez, S. E.; Sandin, S.; Silva, G. G. Z.; Smith, J.; Sullivan, C.; Thompson, C.; Vermeij, M. J. A.; Youle, M.; Young, C.; Zgliczynski, B.; Brainard, R.; Edwards, R. A.; Nulton, J.; Thompson, F.; Rohwer, F.

    2016-03-01

    Microbial viruses can control host abundances via density-dependent lytic predator-prey dynamics. Less clear is how temperate viruses, which coexist and replicate with their host, influence microbial communities. Here we show that virus-like particles are relatively less abundant at high host densities. This suggests suppressed lysis where established models predict lytic dynamics are favoured. Meta-analysis of published viral and microbial densities showed that this trend was widespread in diverse ecosystems ranging from soil to freshwater to human lungs. Experimental manipulations showed viral densities more consistent with temperate than lytic life cycles at increasing microbial abundance. An analysis of 24 coral reef viromes showed a relative increase in the abundance of hallmark genes encoded by temperate viruses with increased microbial abundance. Based on these four lines of evidence, we propose the Piggyback-the-Winner model wherein temperate dynamics become increasingly important in ecosystems with high microbial densities; thus ‘more microbes, fewer viruses’.

  17. [Clinical aspects of viral hemorrhagic fever].

    Science.gov (United States)

    Saijo, Masayuki

    2005-12-01

    Viral hemorrhagic fever (VHF) is defined as virus infections that usually cause pyrexia and hemorrhagic symptoms with multiple organ failure. VHF includes following viral infections: Ebola hemorrhagic fever (EHF), Marburg hemorrhagic fever (MHF), Crimean-Congo hemorrhagic fever (CCHF) and Lassa fever. In particular, the causative agents of EHF, MHF, CCHF, and Lassa fever are Ebola, Marburg, CCHF, Lassa viruses, respectively, and regarded as biosafety level-4 pathogens because of their high virulence to humans. Recently, relatively large outbreaks of EHF and MHF have occurred in Africa, and areas of EHF- and MHF-outbreaks seem to be expanding. Although outbreaks of VHF have not been reported in Japan, there is a possibility that the deadly hemorrhagic fever viruses would be introduced to Japan in future. Therefore, preparedness for possible future outbreaks of VHF is necessary in areas without VHF outbreaks.

  18. Potential Pitfalls in Estimating Viral Load Heritability.

    Science.gov (United States)

    Leventhal, Gabriel E; Bonhoeffer, Sebastian

    2016-09-01

    In HIV patients, the set-point viral load (SPVL) is the most widely used predictor of disease severity. Yet SPVL varies over several orders of magnitude between patients. The heritability of SPVL quantifies how much of the variation in SPVL is due to transmissible viral genetics. There is currently no clear consensus on the value of SPVL heritability, as multiple studies have reported apparently discrepant estimates. Here we illustrate that the discrepancies in estimates are most likely due to differences in the estimation methods, rather than the study populations. Importantly, phylogenetic estimates run the risk of being strongly confounded by unrealistic model assumptions. Care must be taken when interpreting and comparing the different estimates to each other.

  19. Crosslinking in viral capsids via tiling theory.

    Science.gov (United States)

    Twarock, R; Hendrix, R W

    2006-06-07

    A vital part of a virus is its protein shell, called the viral capsid, that encapsulates and hence protects the viral genome. It has been shown in Twarock [2004. A tiling approach to vius capsids assembly explaining a structural puzzle in virology. J. Theor. Biol. 226, 477-482] that the surface structures of viruses with icosahedrally symmetric capsids can be modelled in terms of tilings that encode the locations of the protein subunits. This theory is extended here to multi-level tilings in order to model crosslinking structures. The new framework is demonstrated for the case of bacteriophage HK97, and it is shown, how the theory can be used in general to decide if crosslinking, and what type of crosslinking, is compatible from a mathematical point of view with the geometrical surface structure of a virus.

  20. Detection of viral infection by immunofluorescence in formalin-fixed tissues, pretreated with trypsin

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    O. M. Barth

    1988-06-01

    Full Text Available The presence of viral antigen in sections from formalin-fixed and paraffin-embedded human tissues was demonstrated by trypsin digestion followed by direct or indirect immunofluorescence. The specimens may be used for retrospective diagnosis. The immunofluorescence technique has to be adapted to the suspected virus infection on the basis of previous histopathology study. Variations of trypsin concentration time and temperature of incubation, expose different viral antigens and have to be previously tested for each unknown system. For measles virus detection in lung a stronger digestion has to be applied as compared to adenovirus or respiratory disease viruses in the same tisue. Flavivirus in liver tissue needs a weaker digestion. The reproducibility of the method makes it useful as a routine technique in diagnosis of virus infection.A presença de antígeno viral em cortes de tecidos humanos fixados em formol e emblocados em parafina foi demonstrada pela digestão com tripsina foi demonstrada pela ingestão com tripsina seguida de imunofluorescência direta ou indireta. Os espécimens podem ser utilizados para diagnoses retrospectivas. A técnica da imunofluorescência deve ser adaptada à infecção viral suspeita segundo diagnosie histopatológica prévia. Os parâmetros para a digestão do tecido pela tripsina, relacionados à concentração, duração de atuação e temperatura, expõem diferentes antígenos virais e devem ser previamente testados para cada sistema a ser estabelecido. Uma digestão mais intensa deve ser aplicada para a detecção do vírus do sarampo em tecido pulmonar do que para adenovírus ou vírus respiratório sincicial no mesmo tecido. Por outro lado, o vírus da febre amarela em tecido de fígado necessita de uma digestão mais fraca.

  1. [Bovine viral diarrhea control in Russian Federation].

    Science.gov (United States)

    Guliukin, M I; Iurov, K P; Glotov, A G; Donchenko, N A

    2013-01-01

    Bovine viral diarrhea (BVD) is one of the greatest challenges for breeding and commercial livestock. It is characterized by lesions of the respiratory and gastrointestinal tract, abortion, infertility, immune deficiency, and persistence of the pathogen. In this work, a set of measures for the rehabilitation and prevention of BVD in cattle is described. It includes the data of the literature, guidance documents for the diagnosis and control of BVD adopted by OIE, EU countries, USA, as well as the results of this research.

  2. The epidemiology of viral hepatitis in Qatar

    Directory of Open Access Journals (Sweden)

    Bener Abdulbari

    2009-01-01

    Full Text Available Viral hepatitis is a major public health problem in many countries all over the world and especially in Middle East, Asia, East-Europe, and Africa. The aim of our study was to assess the incidence of viral hepatitis A, B and C in Qatar and compare it with other countries. This is a retrospective cohort study, which was conducted at Hamad General Hospital, State of Qatar from 2002-2006. Patients who were screened and diagnosed with viral hepatitis were included in this study. The diagnostic classification of definite viral hepatitis was made in accordance with criteria based on the International Classification of Disease tenth revision (ICD-10. A total of 527 cases of hepatitis C, 396 cases of hepatitis B, 162 cases of hepatitis A and 108 cases of unspecified were reported during the year 2006. Reported incidence rate per 10,000 populations during the year 2006 for hepatitis A was 1.9, hepatitis B 4.7, and Hepatitis C 6.3. The proportion of hepatitis B and C was significantly higher in male population than females across the years (2002-2006. Hepatitis A was more prevalent in children below 15 years (72.3%, hepatitis B in adults aged above 15 years, and hepatitis C in the population above 35 years of age. The incidence of hepatitis A has been declining in Qataris and increasing in expatriates. There was a significant relationship in gender and age group of the patients with hepatitis A, B and C. We conclude that hepatitis has become a national health issue in Qatar. The incidence rate of hepatitis in Qatar is comparable to its neighboring countries, United Arab Emirates and Saudi Arabia. There is a need for further research on hepatitis and the associated risk factors.

  3. Viral Oncolytic Therapeutics for Neoplastic Meningitis

    Science.gov (United States)

    2014-09-01

    the rat model. The therapeutic effect of HSV-1 oncolysis on meningeal metastases was presented ( oral ) at the annual meeting of the World Molecular...Abstracts, and Presentations Presentations & Abstracts: 1. Oral Presentation at WMIC, Seoul. “Novel oncolytic HSV-1 therapeutics for breast cancer...tomography of herpes simplex virus 1 oncolysis. Cancer Research. 2007; 67(7): 3295. 3. Kuruppu D, Tanabe KK. Viral oncolysis by herpes simplex virus and

  4. Stable cytotoxic T cell escape mutation in hepatitis C virus is linked to maintenance of viral fitness.

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    Luke Uebelhoer

    Full Text Available Mechanisms by which hepatitis C virus (HCV evades cellular immunity to establish persistence in chronically infected individuals are not clear. Mutations in human leukocyte antigen (HLA class I-restricted epitopes targeted by CD8(+ T cells are associated with persistence, but the extent to which these mutations affect viral fitness is not fully understood. Previous work showed that the HCV quasispecies in a persistently infected chimpanzee accumulated multiple mutations in numerous class I epitopes over a period of 7 years. During the acute phase of infection, one representative epitope in the C-terminal region of the NS3/4A helicase, NS3(1629-1637, displayed multiple serial amino acid substitutions in major histocompatibility complex (MHC anchor and T cell receptor (TCR contact residues. Only one of these amino acid substitutions at position 9 (P9 of the epitope was stable in the quasispecies. We therefore assessed the effect of each mutation observed during in vivo infection on viral fitness and T cell responses using an HCV subgenomic replicon system and a recently developed in vitro infectious virus cell culture model. Mutation of a position 7 (P7 TCR-contact residue, I1635T, expectedly ablated the T cell response without affecting viral RNA replication or virion production. In contrast, two mutations at the P9 MHC-anchor residue abrogated antigen-specific T cell responses, but additionally decreased viral RNA replication and virion production. The first escape mutation, L1637P, detected in vivo only transiently at 3 mo after infection, decreased viral production, and reverted to the parental sequence in vitro. The second P9 variant, L1637S, which was stable in vivo through 7 years of follow-up, evaded the antigen-specific T cell response and did not revert in vitro despite being less optimal in virion production compared to the parental virus. These studies suggest that HCV escape mutants emerging early in infection are not necessarily

  5. JC virus promoter/enhancers contain TATA box-associated Spi-B-binding sites that support early viral gene expression in primary astrocytes.

    Science.gov (United States)

    Marshall, Leslie J; Moore, Lisa D; Mirsky, Matthew M; Major, Eugene O

    2012-03-01

    JC virus (JCV) is the aetiological agent of the demyelinating disease progressive multifocal leukoencephalopathy, an AIDS defining illness and serious complication of mAb therapies. Initial infection probably occurs in childhood. In the working model of dissemination, virus persists in the kidney and lymphoid tissues until immune suppression/modulation causes reactivation and trafficking to the brain where JCV replicates in oligodendrocytes. JCV infection is regulated through binding of host factors such as Spi-B to, and sequence variation in the non-coding control region (NCCR). Although NCCR sequences differ between sites of persistence and pathogenesis, evidence suggests that the virus that initiates infection in the brain disseminates via B-cells derived from latently infected haematopoietic precursors in the bone marrow. Spi-B binds adjacent to TATA boxes in the promoter/enhancer of the PML-associated JCV Mad-1 and Mad-4 viruses but not the non-pathogenic, kidney-associated archetype. The Spi-B-binding site of Mad-1/Mad-4 differs from that of archetype by a single nucleotide, AAAAGGGAAGGGA to AAAAGGGAAGGTA. Point mutation of the Mad-1 Spi-B site reduced early viral protein large T-antigen expression by up to fourfold. Strikingly, the reverse mutation in the archetype NCCR increased large T-antigen expression by 10-fold. Interestingly, Spi-B protein binds the NCCR sequence flanking the viral promoter/enhancer, but these sites are not essential for early viral gene expression. The effect of mutating Spi-B-binding sites within the JCV promoter/enhancer on early viral gene expression strongly suggests a role for Spi-B binding to the viral promoter/enhancer in the activation of early viral gene expression.

  6. The prevalence of hepatitis B virus E antigen among Ghanaian blood donors

    Science.gov (United States)

    Rufai, Tanko; Mutocheluh, Mohamed; Kwarteng, Kwaku; Dogbe, Elliot

    2014-01-01

    Hepatitis B viral infection is an important clinical problem due to its worldwide distribution and potential of adverse sequelae, including hepatocellular carcinoma (HCC). We studied the prevalence of hepatitis B virus ‘e’ antigen (HBeAg) among individuals determined to be hepatitis B virus (HBV) surface antigen-positive and analyzed the gender/age category associated with more active HBV infection and whether alteration in the levels of alanine aminotransferase could be associated with HBeAg positivity. A total of 150 prospective blood donors who tested positive for hepatitis B surface antigen (HBsAg) at the blood transfusion center of the Komfo Anokye Teaching Hosptital (KATH), Kumasi were randomly selected for the study. The serum samples were further tested for HBsAg and HBeAg using a lateral flow immunochromatographic assay. Twenty (20) individuals were found to be HBeAg-positive giving an overall prevalence of 13.3%, of which 18 (15.5%) were males and 2 (5.9%) were females. Our results also revealed that the prevalence of HBeAg was higher in patients between the age group of 10-20 years and appeared to decrease with increase in age. There was no statistical difference between the HBeAg positive and negative individuals with respect to alanine aminotransferase (ALT) levels. We show for the first time that approximately 1/10 of HBV-infected individuals are HBeAg positive in the Ashanti Region of Ghana, suggestive of active viral replication and liver-cell infectivity thereby contributing to an increased HBV-transmission pool within the Ghanaian population. PMID:25018803

  7. Selective susceptibility of human skin antigen presenting cells to productive dengue virus infection.

    Directory of Open Access Journals (Sweden)

    Daniela Cerny

    2014-12-01

    Full Text Available Dengue is a growing global concern with 390 million people infected each year. Dengue virus (DENV is transmitted by mosquitoes, thus host cells in the skin are the first point of contact with the virus. Human skin contains several populations of antigen-presenting cells which could drive the immune response to DENV in vivo: epidermal Langerhans cells (LCs, three populations of dermal dendritic cells (DCs, and macrophages. Using samples of normal human skin we detected productive infection of CD14(+ and CD1c(+ DCs, LCs and dermal macrophages, which was independent of DC-SIGN expression. LCs produced the highest viral titers and were less sensitive to IFN-β. Nanostring gene expression data showed significant up-regulation of IFN-β, STAT-1 and CCL5 upon viral exposure in susceptible DC populations. In mice infected intra-dermally with DENV we detected parallel populations of infected DCs originating from the dermis and migrating to the skin-draining lymph nodes. Therefore dermal DCs may simultaneously facilitate systemic spread of DENV and initiate the adaptive anti-viral immune response.

  8. Systemic and mucosal immune responses to sublingual or intramuscular human papilloma virus antigens in healthy female volunteers.

    Directory of Open Access Journals (Sweden)

    Zhiming Huo

    Full Text Available The sublingual route has been proposed as a needle-free option to induce systemic and mucosal immune protection against viral infections. In a translational study of systemic and mucosal humoral immune responses to sublingual or systemically administered viral antigens, eighteen healthy female volunteers aged 19-31 years received three immunizations with a quadravalent Human Papilloma Virus vaccine at 0, 4 and 16 weeks as sublingual drops (SL, n = 12 or intramuscular injection (IM, n = 6. IM antigen delivery induced or boosted HPV-specific serum IgG and pseudovirus-neutralizing antibodies, HPV-specific cervical and vaginal IgG, and elicited circulating IgG and IgA antibody secreting cells. SL antigens induced ~38-fold lower serum and ~2-fold lower cervical/vaginal IgG than IM delivery, and induced or boosted serum virus neutralizing antibody in only 3/12 subjects. Neither route reproducibly induced HPV-specific mucosal IgA. Alternative delivery systems and adjuvants will be required to enhance and evaluate immune responses following sublingual immunization in humans.ClinicalTrials.govNCT00949572.

  9. Endogenous viral elements in algal genomes

    Institute of Scientific and Technical Information of China (English)

    WANG Liang; YU Jun; WU Shuangxiu; LIU Tao; SUN Jing; CHI Shan; LIU Cui; LI Xingang; YIN Jinlong; WANG Xumin

    2014-01-01

    Endogenous viral elements (EVEs) are host-genomic fragments originated from viral genomes. They have been found universally in animal and plant genomes. Here we carried out a systematic screening and analy-sis of EVEs in algal genomes and found that EVEs commonly exist in algal genomes. We classified the EVE fragments into three categories according to the length of EVE fragments. Due to the probability of sequence similarity by chance, we ignored the potential function of medium-length EVE fragments. However, long-length EVE fragments probably had capability to encode protein domains or even entire proteins, and some short-length EVE fragments had high similarity with host's siRNA sequences and possibly served functions of small RNAs. Therefore, short and long EVE fragments might provide regulomic and proteomic novelty to the host's metabolism and adaptation. We also found several EVE fragments shared by more than 3 algal genomes. By phylogenetic analysis of the shared EVEs and their corresponding species, we found that the integration of viral fragments into host genomes was an ancient event, possibly before the divergence of Chlorophytes and Ochrophytes. Our findings show that there is a frequent genetic flow from viruses to algal genomes. Moreover, study on algal EVEs shed light on the virus-host interaction in large timescale and could also help us understand the balance of marine ecosystems.

  10. Viral quasispecies assembly via maximal clique enumeration.

    Directory of Open Access Journals (Sweden)

    Armin Töpfer

    2014-03-01

    Full Text Available Virus populations can display high genetic diversity within individual hosts. The intra-host collection of viral haplotypes, called viral quasispecies, is an important determinant of virulence, pathogenesis, and treatment outcome. We present HaploClique, a computational approach to reconstruct the structure of a viral quasispecies from next-generation sequencing data as obtained from bulk sequencing of mixed virus samples. We develop a statistical model for paired-end reads accounting for mutations, insertions, and deletions. Using an iterative maximal clique enumeration approach, read pairs are assembled into haplotypes of increasing length, eventually enabling global haplotype assembly. The performance of our quasispecies assembly method is assessed on simulated data for varying population characteristics and sequencing technology parameters. Owing to its paired-end handling, HaploClique compares favorably to state-of-the-art haplotype inference methods. It can reconstruct error-free full-length haplotypes from low coverage samples and detect large insertions and deletions at low frequencies. We applied HaploClique to sequencing data derived from a clinical hepatitis C virus population of an infected patient and discovered a novel deletion of length 357±167 bp that was validated by two independent long-read sequencing experiments. HaploClique is available at https://github.com/armintoepfer/haploclique. A summary of this paper appears in the proceedings of the RECOMB 2014 conference, April 2-5.

  11. Viral quasispecies assembly via maximal clique enumeration.

    Science.gov (United States)

    Töpfer, Armin; Marschall, Tobias; Bull, Rowena A; Luciani, Fabio; Schönhuth, Alexander; Beerenwinkel, Niko

    2014-03-01

    Virus populations can display high genetic diversity within individual hosts. The intra-host collection of viral haplotypes, called viral quasispecies, is an important determinant of virulence, pathogenesis, and treatment outcome. We present HaploClique, a computational approach to reconstruct the structure of a viral quasispecies from next-generation sequencing data as obtained from bulk sequencing of mixed virus samples. We develop a statistical model for paired-end reads accounting for mutations, insertions, and deletions. Using an iterative maximal clique enumeration approach, read pairs are assembled into haplotypes of increasing length, eventually enabling global haplotype assembly. The performance of our quasispecies assembly method is assessed on simulated data for varying population characteristics and sequencing technology parameters. Owing to its paired-end handling, HaploClique compares favorably to state-of-the-art haplotype inference methods. It can reconstruct error-free full-length haplotypes from low coverage samples and detect large insertions and deletions at low frequencies. We applied HaploClique to sequencing data derived from a clinical hepatitis C virus population of an infected patient and discovered a novel deletion of length 357±167 bp that was validated by two independent long-read sequencing experiments. HaploClique is available at https://github.com/armintoepfer/haploclique. A summary of this paper appears in the proceedings of the RECOMB 2014 conference, April 2-5.

  12. Viral hepatitis and liver cancer on the Island of Guam.

    Science.gov (United States)

    Haddock, R L; Paulino, Y C; Bordallo, R

    2013-01-01

    Patient records from the Guam Cancer Registry were compared with patients listed in a health department viral hepatitis case registry and the numbers of liver cancer and viral hepatitis cases were compared by ethnicity. Hepatitis C was the form of viral hepatitis most common among liver cancer cases on Guam (63.3% of viral hepatitis-associated liver cancer cases). Since viral hepatitis is an important cause of liver cancer, studies such as the present one may provide the information necessary to establish programs (screening of populations at risk and infant vaccination in the case of hepatitis B, for example) that may lessen the impact of liver cancer in the future.

  13. Expression and Antigenic Evaluation of VacA Antigenic Fragment of Helicobacter Pylori

    Directory of Open Access Journals (Sweden)

    Leila Hasanzadeh

    2013-07-01

    Full Text Available Objective(s: Helicobacter pylori, a human specific gastric pathogen is a causative agent of chronic active gastritis. The vacuolating cytotoxin (VacA is an effective virulence factor involved in gastric injury. The aim of this study was to construct a recombinant protein containing antigenic region of VacA gene and determine its antigenicity.   Materials and Methods: The antigenic region of VacA gene was detected by bioinformatics methods. The polymerase chain reaction method was used to amplify a highly antigenic region of VacA gene from chromosomal DNA of H. pylori. The eluted product was cloned into the prokaryotic expression vector pET32a. The target protein was expressed in the Escherichia coli BL21 (DE3 pLysS. The bacteria including pET32a-VacA plasmids were induced by IPTG. The antigenicity was finally studied by western blotting using sera of 15 H. pylori infected patients after purification. Results: Enzyme digestion analysis, PCR and DNA sequencing results showed that the target gene was inserted correctly into the recombinant vector. The expressed protein was purified successfully via affinity chromatography. Data indicated that antigenic region of VacA protein from Helicobacter pylori was recognized by all 15 patient’s sera. Conclusion : Our data showed that antigenic region of VacA protein can be expressed by in E. co.li. This protein was recognized by sera patients suffering from H. pylori infection. the recombinant protein has similar epitopes and close antigenic properties to the natural form of this antigen. Recombinant antigenic region of VacA protein also seems to be a promising antigen for protective and serologic diagnosis .

  14. Replicon RNA Viral Vectors as Vaccines

    Science.gov (United States)

    Lundstrom, Kenneth

    2016-01-01

    Single-stranded RNA viruses of both positive and negative polarity have been used as vectors for vaccine development. In this context, alphaviruses, flaviviruses, measles virus and rhabdoviruses have been engineered for expression of surface protein genes and antigens. Administration of replicon RNA vectors has resulted in strong immune responses and generation of neutralizing antibodies in various animal models. Immunization of mice, chicken, pigs and primates with virus-like particles, naked RNA or layered DNA/RNA plasmids has provided protection against challenges with lethal doses of infectious agents and administered tumor cells. Both prophylactic and therapeutic efficacy has been achieved in cancer immunotherapy. Moreover, recombinant particles and replicon RNAs have been encapsulated by liposomes to improve delivery and targeting. Replicon RNA vectors have also been subjected to clinical trials. Overall, immunization with self-replicating RNA viruses provides high transient expression levels of antigens resulting in generation of neutralizing antibody responses and protection against lethal challenges under safe conditions. PMID:27827980

  15. Ethanol Metabolism Alters Major Histocompatibility Complex Class I-Restricted Antigen Presentation In Liver Cells

    Science.gov (United States)

    Osna, Natalia A.; White, Ronda L.; Thiele, Geoffrey M.; Donohue, Terrence M.

    2009-01-01

    The proteasome is a major enzyme that cleaves proteins for antigen presentation. Cleaved peptides traffic to the cell surface, where they are presented in the context of MHC class I. Recognition of these complexes by cytotoxic T lymphocytes is crucial for elimination of cells bearing “non-self” proteins. Our previous studies revealed that ethanol suppresses proteasome function in ethanol-metabolizing liver cells. We hypothesized that proteasome suppression reduces the hydrolysis of antigenic peptides, thereby decreasing the presentation of the peptide-MHC class I-complexes on the cell surface. To test this, we used the mouse hepatocyte cell line (CYP2E1/ADH-transfected HepB5 cells) or primary mouse hepatocytes, both derived from livers of C57Bl/6 mice, which present the ovalbumin peptide, SIINFEKL, complexed with H2Kb. To induce H2Kb expression, HepB5 cells were treated with interferon gamma (IFNγ) and then exposed to ethanol. In these cells, ethanol metabolism decreased not only proteasome activity, but also hydrolysis of the C-extended peptide, SIINFEKL-TE and the presentation of SIINFEKL-H2Kb complexes measured after the delivery of SIINFEKL-TE to cytoplasm. The suppressive effects of ethanol were, in part, attributed to ethanol-elicited impairment of IFNγ signaling. However, in primary hepatocytes, even in the absence of IFNγ, we observed a similar decline in proteasome activity and antigen presentation after ethanol exposure. We conclude that proteasome function is directly suppressed by ethanol metabolism and indirectly, by preventing the activating effects of IFNγ. Ethanol-elicited reduction in proteasome activity contributes to the suppression of SIINFEKL-H2Kb presentation on the surface of liver cells. Immune response to viral antigens plays a crucial role in the pathogenesis of hepatitis C or B viral infections (HCV and HBV, respectively). Professional antigen-presenting cells (dendritic cells and macrophages) are responsible for priming the

  16. Oral immunogenicity of potato-derived antigens to Mycobacterium tuberculosis in mice

    Institute of Scientific and Technical Information of China (English)

    Yi Zhang; Suting Chen; Jiayun Li; Yuan Liu; Yuanlei Hu; Hong Cai

    2012-01-01

    The novel use of transgenic plants as vectors for the expression of viral and bacterial antigens has been increasingly tested as an alternative methodology for the production and delivery of experimental oral vaccines.Here,we examined the immunogenicity of combined plant-made vaccines that include four genes encoding immune-dominant antigens from Mycobacterium tuberculosis.Compared with the wild type and other control groups,mice treated with the combined plant-made vaccines showed significantly higher levels of interferon-γ and interleukin-2 production in response to all four proteins,and higher levels of antigenspecific CD4+ and CD8+ T-cell responses and immunoglobulin (lg) G and IgA titers.These results suggest that combined plant-made vaccines can induce immunogenicity against M.tuberculosis through the induction of stronger Th1-associated immune responses.This is the first report of an orally delivered combined plant-made vaccine against tuberculosis priming an antigen-specific Th1 response,a comprehensive effect including both mucosal and systemic immune responses.

  17. Pathogens Inactivated by Low-Energy-Electron Irradiation Maintain Antigenic Properties and Induce Protective Immune Responses

    Science.gov (United States)

    Fertey, Jasmin; Bayer, Lea; Grunwald, Thomas; Pohl, Alexandra; Beckmann, Jana; Gotzmann, Gaby; Casado, Javier Portillo; Schönfelder, Jessy; Rögner, Frank-Holm; Wetzel, Christiane; Thoma, Martin; Bailer, Susanne M.; Hiller, Ekkehard; Rupp, Steffen; Ulbert, Sebastian

    2016-01-01

    Inactivated vaccines are commonly produced by incubating pathogens with chemicals such as formaldehyde or β-propiolactone. This is a time-consuming process, the inactivation efficiency displays high variability and extensive downstream procedures are often required. Moreover, application of chemicals alters the antigenic components of the viruses or bacteria, resulting in reduced antibody specificity and therefore stimulation of a less effective immune response. An alternative method for inactivation of pathogens is ionizing radiation. It acts very fast and predominantly damages nucleic acids, conserving most of the antigenic structures. However, currently used irradiation technologies (mostly gamma-rays and high energy electrons) require large and complex shielding constructions to protect the environment from radioactivity or X-rays generated during the process. This excludes them from direct integration into biological production facilities. Here, low-energy electron irradiation (LEEI) is presented as an alternative inactivation method for pathogens in liquid solutions. LEEI can be used in normal laboratories, including good manufacturing practice (GMP)- or high biosafety level (BSL)-environments, as only minor shielding is necessary. We show that LEEI efficiently inactivates different viruses (influenza A (H3N8), porcine reproductive and respiratory syndrome virus (PRRSV), equine herpesvirus 1 (EHV-1)) and bacteria (Escherichia coli) and maintains their antigenicity. Moreover, LEEI-inactivated influenza A viruses elicit protective immune responses in animals, as analyzed by virus neutralization assays and viral load determination upon challenge. These results have implications for novel ways of developing and manufacturing inactivated vaccines with improved efficacy. PMID:27886076

  18. Antigenicity and Hemaglutination Activity of a Recombinant Hemagglutinin-Neuraminidase of Paramyxovirus Tianjin Strain

    Institute of Scientific and Technical Information of China (English)

    Mei LI; Li-jun YUAN; Li-ying SHI; Xiao-mian LI; Qing WANG; Wen-xiu WANG

    2008-01-01

    Paramyxovirus Tianjin strain, a new genotype of Sendal virus, was isolated from the lungs of common cotton-eared marmoset that died of severe respiratory infection in the marmoset colonies. The 19.28% IgM positive rate in the young children with acute respiratory tract infection suggested a close relationship between Tianjin strain and humans. Hemagglutinin-neuraminidase (HN) is its major transmembrane glycoprotein responsible for viral attachment, penetration and release. To clear the relationship between HN structure and function of paramyxovirus Tianjin strain, rHN1, rHN2 and rHN3 overlapping the ectodomain of HN protein were expressed. Their antigenicity and hemaglutination activity, as well as cross reactivity to standard antisera against influenza virus type A, type B were analyzed. The results indicated expressed rHNs have the natural antigenicity.The segment rHN2 possesses more linear epitopes exposed on the surface of the native I-IN protein than found in segments rHN3 and rHN1. The hemagglutination activity of segment rHN3 is higher than that of segments rHN2 and rHN1, and partially dependent on the three-dimensional conformation of HN3 protein. Cross-reactivity between rHNs and standard antisera against influenza virus type A, type B suggested that rHNs might not be the best alternative as specific antigens to detect virus in clinicalserum specimens.

  19. Antigen cross-presentation of immune complexes.

    Science.gov (United States)

    Platzer, Barbara; Stout, Madeleine; Fiebiger, Edda

    2014-01-01

    The ability of dendritic cells (DCs) to cross-present tumor antigens has long been a focus of interest to physicians, as well as basic scientists, that aim to establish efficient cell-based cancer immune therapy. A prerequisite for exploiting this pathway for therapeutic purposes is a better understanding of the mechanisms that underlie the induction of tumor-specific cytotoxic T-lymphocyte (CTL) responses when initiated by DCs via cross-presentation. The ability of humans DC to perform cross-presentation is of utmost interest, as this cell type is a main target for cell-based immunotherapy in humans. The outcome of a cross-presentation event is guided by the nature of the antigen, the form of antigen uptake, and the subpopulation of DCs that performs presentation. Generally, CD8α(+) DCs are considered to be the most potent cross-presenting DCs. This paradigm, however, only applies to soluble antigens. During adaptive immune responses, immune complexes form when antibodies interact with their specific epitopes on soluble antigens. Immunoglobulin G (IgG) immune complexes target Fc-gamma receptors on DCs to shuttle exogenous antigens efficiently into the cross-presentation pathway. This receptor-mediated cross-presentation pathway is a well-described route for the induction of strong CD8(+) T cell responses. IgG-mediated cross-presentation is intriguing because it permits the CD8(-) DCs, which are commonly considered to be weak cross-presenters, to efficiently cross-present. Engaging multiple DC subtypes for cross-presentation might be a superior strategy to boost CTL responses in vivo. We here summarize our current understanding of how DCs use IgG-complexed antigens for the efficient induction of CTL responses. Because of its importance for human cell therapy, we also review the recent advances in the characterization of cross-presentation properties of human DC subsets.

  20. Viral Vectors for in Vivo Gene Transfer

    Science.gov (United States)

    Thévenot, E.; Dufour, N.; Déglon, N.

    The transfer of DNA into the nucleus of a eukaryotic cell (gene transfer) is a central theme of modern biology. The transfer is said to be somatic when it refers to non-germline organs of a developed individual, and germline when it concerns gametes or the fertilised egg of an animal, with the aim of transmitting the relevant genetic modification to its descendents [1]. The efficient introduction of genetic material into a somatic or germline cell and the control of its expression over time have led to major advances in understanding how genes work in vivo, i.e., in living organisms (functional genomics), but also to the development of innovative therapeutic methods (gene therapy). The efficiency of gene transfer is conditioned by the vehicle used, called the vector. Desirable features for a vector are as follows: Easy to produce high titer stocks of the vector in a reproducible way. Absence of toxicity related to transduction (transfer of genetic material into the target cell, and its expression there) and no immune reaction of the organism against the vector and/or therapeutic protein. Stability in the expression of the relevant gene over time, and the possibility of regulation, e.g., to control expression of the therapeutic protein on the physiological level, or to end expression at the end of treatment. Transduction of quiescent cells should be as efficient as transduction of dividing cells. Vectors currently used fall into two categories: non-viral and viral vectors. In non-viral vectors, the DNA is complexed with polymers, lipids, or cationic detergents (described in Chap. 3). These vectors have a low risk of toxicity and immune reaction. However, they are less efficient in vivo than viral vectors when it comes to the number of cells transduced and long-term transgene expression. (Naked DNA transfer or electroporation is rather inefficient in the organism. This type of gene transfer will not be discussed here, and the interested reader is referred to the