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Sample records for ccr5-tropic chimeric virus

  1. RT-SHIV, an infectious CCR5-tropic chimeric virus suitable for evaluating HIV reverse transcriptase inhibitors in macaque models

    Directory of Open Access Journals (Sweden)

    Emau Peter

    2009-11-01

    Full Text Available Abstract Background Non-nucleoside reverse transcriptase inhibitors (NNRTIs are an important category of drugs for both chemotherapy and prevention of human immunodeficiency virus type 1 (HIV-1 infection. However, current non-human primate (NHP models utilizing simian immunodeficiency virus (SIV or commonly used chimeric SHIV (SIV expressing HIV-1 envelope are inadequate due to the insensitivity to NNRTIs. To develop a NHP model for evaluation of NNRTI compounds, we characterized a RT-SHIV virus that was assembled by replacing the SIVmac239 reverse transcriptase (RT with that of HIV-1HXB2. Since RT-SHIV exhibited in vitro characteristics of high infectivity, CCR5-usage, and sensitivity to HIV-1 specific NNRTIs, this virus was thought to be suitable for mucosal transmission and then was used to carry out a vaginal transmission study in pigtail macaques (Macaca nemestrina. Results RT-SHIV exhibited in vitro characteristics of an infectious CCR5-tropic chimeric virus. This virus was not only highly sensitive to HIV-1 RT specific NNRTIs; its replication was also inhibited by a variety of NRTIs and protease inhibitors. For in vivo vaginal transmission studies, macaques were either pretreated with a single dose of DMPA (depot medroxyprogesterone acetate or left untreated before intravaginal inoculation with 500 or 1,000 TCID50 of RT-SHIV. All macaques became systemically infected by 2 or 3 weeks post-inoculation exhibiting persistent high viremia, marked CD4+T cell depletion, and antiviral antibody response. DMPA-pretreated macaques showed a higher mean plasma viral load after the acute infection stage, highly variable antiviral antibody response, and a higher incidence of AIDS-like disease as compared with macaques without DMPA pretreatment. Conclusion This chimeric RT-SHIV has exhibited productive replication in both macaque and human PBMCs, predominantly CCR5-coreceptor usage for viral entry, and sensitivity to NNRTIs as well as other anti

  2. Pathogenic infection of Macaca nemestrina with a CCR5-tropic subtype-C simian-human immunodeficiency virus

    Directory of Open Access Journals (Sweden)

    Song Ruijiang

    2009-07-01

    Full Text Available Abstract Background Although pig-tailed macaques (Macaca nemestrina have been used in AIDS research for years, less is known about the early immunopathogenic events in this species, as compared to rhesus macaques (Macaca mulatta. Similarly, the events in early infection are well-characterized for simian immunodeficiency viruses (SIV, but less so for chimeric simian-human immunodeficiency viruses (SHIV, although the latter have been widely used in HIV vaccine studies. Here, we report the consequences of intrarectal infection with a CCR5-tropic clade C SHIV-1157ipd3N4 in pig-tailed macaques. Results Plasma and cell-associated virus was detectable in peripheral blood and intestinal tissues of all four pig-tailed macaques following intrarectal inoculation with SHIV-1157ipd3N4. We also observed a rapid and irreversible loss of CD4+ T cells at multiple mucosal sites, resulting in a marked decrease of CD4:CD8 T cell ratios 0.5–4 weeks after inoculation. This depletion targeted subsets of CD4+ T cells expressing the CCR5 coreceptor and having a CD28-CD95+ effector memory phenotype, consistent with the R5-tropism of SHIV-1157ipd3N4. All three animals that were studied beyond the acute phase seroconverted as early as week 4, with two developing cross-clade neutralizing antibody responses by week 24. These two animals also demonstrated persistent plasma viremia for >48 weeks. One of these animals developed AIDS, as shown by peripheral blood CD4+ T-cell depletion starting at 20 weeks post inoculation. Conclusion These findings indicate that SHIV-1157ipd3N4-induced pathogenesis in pig-tailed macaques followed a similar course as SIV-infected rhesus macaques. Thus, R5 SHIV-C-infection of pig-tailed macaques could provide a useful and relevant model for AIDS vaccine and pathogenesis research.

  3. Significantly reduced CCR5-tropic HIV-1 replication in vitro in cells from subjects previously immunized with Vaccinia Virus

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    Alibek Kenneth

    2010-05-01

    Full Text Available Abstract Background At present, the relatively sudden appearance and explosive spread of HIV throughout Africa and around the world beginning in the 1950s has never been adequately explained. Theorizing that this phenomenon may be somehow related to the eradication of smallpox followed by the cessation of vaccinia immunization, we undertook a comparison of HIV-1 susceptibility in the peripheral blood mononuclear cells from subjects immunized with the vaccinia virus to those from vaccinia naive donors. Results Vaccinia immunization in the preceding 3-6 months resulted in an up to 5-fold reduction in CCR5-tropic but not in CXCR4-tropic HIV-1 replication in the cells from vaccinated subjects. The addition of autologous serum to the cell cultures resulted in enhanced R5 HIV-1 replication in the cells from unvaccinated, but not vaccinated subjects. There were no significant differences in the concentrations of MIP-1α, MIP-1β and RANTES between the cell cultures derived from vaccinated and unvaccinated subjects when measured in culture medium on days 2 and 5 following R5 HIV-1 challenge. Discussion Since primary HIV-1 infections are caused almost exclusively by the CCR5-tropic HIV-1 strains, our results suggest that prior immunization with vaccinia virus might provide an individual with some degree of protection to subsequent HIV infection and/or progression. The duration of such protection remains to be determined. A differential elaboration of MIP-1α, MIP-1β and RANTES between vaccinated and unvaccinated subjects, following infection, does not appear to be a mechanism in the noted protection.

  4. Construction and characterization of chimeric BHIV (BIV/HIV-1) viruses carrying the bovine immunodeficiency virus gag gene

    OpenAIRE

    Zhu, Yi-Xin; Liu, Chang; Liu, Xin-Lei; Qiao, Wen-Tao; Chen, Qi-Min; Zeng, Yi; Geng, Yun-Qi

    2005-01-01

    AIM: To explore the possibility of the replacement of the gag gene between human immunodeficiency virus and bovine immunodeficiency virus, to achieve chimeric virions, and thereby gain a new kind of AIDS vaccine based on BHIV chimeric viruses.

  5. 78 FR 16505 - Prospective Grant of Exclusive License: Chimeric West Nile/Dengue Viruses

    Science.gov (United States)

    2013-03-15

    ...: Chimeric West Nile/Dengue Viruses AGENCY: Centers for Disease Control and Prevention (CDC), Department of... license, in the field of use of in vitro diagnostics for dengue virus infection, to practice the... Application 61/049,342, filed 4/30/2008, entitled ``Engineered, Chimeric West Nile/Dengue Viruses;''...

  6. Chimeric viruses blur the borders between the major groups of eukaryotic single-stranded DNA viruses

    OpenAIRE

    Roux, Simon; Enault, Francois; Bronner, Gisèle; Vaulot, Daniel; Forterre, Patrick; Krupovic, Mart

    2013-01-01

    Metagenomic studies have uncovered an astonishing diversity of ssDNA viruses encoding replication proteins (Reps) related to those of eukaryotic Circoviridae, Geminiviridae or Nanoviridae; however, exact evolutionary relationships among these viruses remain obscure. Recently, a unique chimeric virus (CHIV) genome, which has apparently emerged via recombination between ssRNA and ssDNA viruses, has been discovered. Here we report on the assembly of 13 new CHIV genomes recovered f...

  7. Construction and characterization of chimeric BHIV (BIV/HIV-1) viruses carrying the bovine immunodeficiency virus gag gene

    Institute of Scientific and Technical Information of China (English)

    Yi-Xin Zhu; Chang Liu; Xin-Lei Liu; Wen-Tao Qiao; Qi-Min Chen; Yi Zeng; Yun-Qi Geng

    2005-01-01

    AIM: To explore the possibility of the replacement of the gag gene between human immunodeficiency virus and bovine immunodeficiency virus, to achieve chimeric virions,and thereby gain a new kind of AIDS vaccine based on BHIV chimeric viruses.METHODS: A series of chimeric BHIV proviral DNAs differing in the replacement regions in gag gene were constructed, and then were transfected into 293T cells. The expression of chimeric viral genes was detected at the RNA and protein level. The supematant of 293T cell was ultra centrifuged to detect the probable chimeric virion. Once the chimeric virion was detected, its biological activities were also assayed by infecting HIV-sensitive MT4 cells.RESULTS: Four chimeric BHIV proviral DNAs were constructed. Genes in chimeric viruses expressed correctly in transfected 293T cells. All four constructs assembled chimeric virions with different degrees of efficiency. These virions had complete structures common to retroviruses and packaged genomic RNAs, but the cleavages of the precursor Gag proteins were abnormal to some extent. Three of these virions tested could attach and enter into MT4 cells, and one of them could complete the course of reverse transcription. Yet none of them could replicate in MT4 cells.CONCLUSION: The replacement of partial gag gene of HIV with BIV gaggene is feasible. Genes in chimeric BHIVs are accurately expressed, and virions are assembled. These chimeric BHIVs (proviral DNA together with virus particles) have the potential to become a new kind of HIV/AIDS vaccine.

  8. A chimeric measles virus with a lentiviral envelope replicates exclusively in CD4+/CCR5+ cells

    International Nuclear Information System (INIS)

    We generated a replicating chimeric measles virus in which the hemagglutinin and fusion surface glycoproteins were replaced with the gp160 envelope glycoprotein of simian immunodeficiency virus (SIVmac239). Based on a previously cloned live-attenuated Schwarz vaccine strain of measles virus (MV), this chimera was rescued at high titers using reverse genetics in CD4+ target cells. Cytopathic effect consisted in the presence of large cell aggregates evolving to form syncytia, as observed during SIV infection. The morphology of the chimeric virus was identical to that of the parent MV particles. The presence of SIV gp160 as the only envelope protein on chimeric particles surface altered the cell tropism of the new virus from CD46+ to CD4+ cells. Used as an HIV candidate vaccine, this MV/SIVenv chimeric virus would mimic transient HIV-like infection, benefiting both from HIV-like tropism and the capacity of MV to replicate in dendritic cells, macrophages and lymphocytes.

  9. Chimeric hepatitis B virus core particles as probes for studying peptide-integrin interactions.

    OpenAIRE

    Chambers, M A; Dougan, G; Newman, J.; Brown, F.; Crowther, J.; Mould, A P; Humphries, M J; Francis, M. J.; Clarke, B.; Brown, A L; Rowlands, D.

    1996-01-01

    An RGD-containing epitope from the foot-and-mouth disease virus (FMDV) VP1 protein was inserted into the e1 loop of the hepatitis B virus core (HBc) protein. This chimeric protein was expressed at high levels in Escherichia coli and spontaneously assembled into virus-like particles which could be readily purified. These fusion particles elicited high levels of both enzyme-linked immunosorbent assay- and FMDV-neutralizing antibodies in guinea pigs. The chimeric particles bound specifically to ...

  10. Chimeric viruses blur the borders between the major groups of eukaryotic single-stranded DNA viruses.

    Science.gov (United States)

    Roux, Simon; Enault, François; Bronner, Gisèle; Vaulot, Daniel; Forterre, Patrick; Krupovic, Mart

    2013-01-01

    Metagenomic studies have uncovered an astonishing diversity of ssDNA viruses encoding replication proteins (Reps) related to those of eukaryotic Circoviridae, Geminiviridae or Nanoviridae; however, exact evolutionary relationships among these viruses remain obscure. Recently, a unique chimeric virus (CHIV) genome, which has apparently emerged via recombination between ssRNA and ssDNA viruses, has been discovered. Here we report on the assembly of 13 new CHIV genomes recovered from various environments. Our results indicate a single event of capsid protein (CP) gene capture from an RNA virus in the history of this virus group. The domestication of the CP gene was followed by an unprecedented recurrent replacement of the Rep genes in CHIVs with distant counterparts from diverse ssDNA viruses. We suggest that parasitic and symbiotic interactions between unicellular eukaryotes were central for the emergence of CHIVs and that such turbulent evolution was primarily dictated by incongruence between the CP and Rep proteins. PMID:24193254

  11. Generation and evaluation of a chimeric classical swine fever virus expressing a visible marker gene.

    Science.gov (United States)

    Li, Yongfeng; Wang, Xiao; Sun, Yuan; Li, Lian-Feng; Zhang, Lingkai; Li, Su; Luo, Yuzi; Qiu, Hua-Ji

    2016-03-01

    Classical swine fever virus (CSFV) is a noncytopathogenic virus, and the incorporation of an enhanced green fluorescent protein (EGFP) tag into the viral genome provides a means of direct monitoring of viral infection without immunostaining. It is well established that the 3' untranslated region (3'-UTR) of the CSFV plays an important role in viral RNA replication. Although CSFV carrying a reporter gene and chimeric CSFV have been generated and evaluated, a chimeric CSFV with a visible marker has not yet been reported. Here, we generated and evaluated a chimeric virus containing the EGFP tag and the 3'-UTR from vaccine strain HCLV (C-strain) in the genetic background of the highly virulent CSFV Shimen strain. The chimeric marker CSFV was fluorescent and had an approximately 100-fold lower viral titer, lower replication level of viral genome, and weaker fluorescence intensity than the recombinant CSFV with only the EGFP tag or the parental virus. Furthermore, the marker chimera was avirulent and displayed no viremia in inoculated pigs, which were completely protected from lethal CSFV challenge as early as 15 days post-inoculation. The chimeric marker virus was visible in vitro and attenuated in vitro and in vivo, which suggests that CSFV can be engineered to produce attenuated variants with a visible marker to facilitate in vitro studies of CSFV infection and replication and to develop of novel vaccines against CSF. PMID:26614259

  12. Chimeric SV40 virus-like particles induce specific cytotoxicity and protective immunity against influenza A virus without the need of adjuvants

    International Nuclear Information System (INIS)

    Virus-like particles (VLPs) are a promising vaccine platform due to the safety and efficiency. However, it is still unclear whether polyomavirus-based VLPs are useful for this purpose. Here, we attempted to evaluate the potential of polyomavirus VLPs for the antiviral vaccine using simian virus 40 (SV40). We constructed chimeric SV40-VLPs carrying an HLA-A⁎02:01-restricted, cytotoxic T lymphocyte (CTL) epitope derived from influenza A virus. HLA-A⁎02:01-transgenic mice were then immunized with the chimeric SV40-VLPs. The chimeric SV40-VLPs effectively induced influenza-specific CTLs and heterosubtypic protection against influenza A viruses without the need of adjuvants. Because DNase I treatment of the chimeric SV40-VLPs did not disrupt CTL induction, the intrinsic adjuvant property may not result from DNA contaminants in the VLP preparation. In addition, immunization with the chimeric SV40-VLPs generated long-lasting memory CTLs. We here propose that the chimeric SV40-VLPs harboring an epitope may be a promising CTL-based vaccine platform with self-adjuvant properties. - Highlights: • We constructed chimeric SV40-VLPs carrying an influenza virus-derived CTL epitope. • Chimeric SV40-VLPs induce influenza-specific CTLs in mice without adjuvants. • Chimeric SV40-VLPs induce heterosubtypic protection against influenza A viruses. • Chimeric SV40-VLPs induce long-lasting memory CTLs. • Chimeric SV40-VLPs is a promising vaccine platform with self-adjuvant properties

  13. Chimeric Rabies Virus-Like Particles Containing Membrane-Anchored GM-CSF Enhances the Immune Response against Rabies Virus

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    Hongtao Kang; Yinglin Qi; Hualei Wang; Xuexing Zheng; Yuwei Gao; Nan Li; Songtao Yang; Xianzhu Xia

    2015-01-01

    Rabies remains an important public health threat in most developing countries. To develop a more effective and safe vaccine against rabies, we have constructed a chimeric rabies virus-like particle (VLP), which containing glycoprotein (G) and matrix protein (M) of rabies virus (RABV) Evelyn-Rokitnicki-Abelseth (ERA) strain, and membrane-anchored granulocyte-macrophage colony-stimulating factor (GM-CSF), and it was named of EVLP-G. The immunogenicity and protective efficacy of EVLP-G against R...

  14. Chimeric plant virus particles administered nasally or orally induce systemic and mucosal immune responses in mice

    DEFF Research Database (Denmark)

    Brennan, F.R.; Bellaby, T.; Helliwell, S.M.;

    1999-01-01

    The humoral immune responses to the D2 peptide of fibronectin-binding protein B (FnBP) of Staphylococcus aureus, expressed on the plant virus cowpea mosaic virus (CPMV), were evaluated after mucosal delivery to mice. Intranasal immunization of these chimeric virus particles (CVPs), either alone or...... of CVPs to generate antibody at distant mucosal sites. IgG2a and TgG2b were the dominant IgG subclasses in sera to both CPMV and FnBP, demonstrating a bias in the response toward the T helper 1 type. The sera completely inhibited the binding of human fibronectin to the S. aureus FnBP. Oral...

  15. Chimeric SV40 virus-like particles induce specific cytotoxicity and protective immunity against influenza A virus without the need of adjuvants

    Energy Technology Data Exchange (ETDEWEB)

    Kawano, Masaaki [Department of Allergy and Immunology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Morikawa, Katsuma [Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501 (Japan); Suda, Tatsuya [Department of Microbiology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Laboratory for Immunopharmacology of Microbial Products, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan); Ohno, Naohito [Laboratory for Immunopharmacology of Microbial Products, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan); Matsushita, Sho [Department of Allergy and Immunology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Allergy Center, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Akatsuka, Toshitaka [Department of Microbiology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Handa, Hiroshi, E-mail: handa.h.aa@m.titech.ac.jp [Solutions Research Laboratory, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8503 (Japan); Matsui, Masanori, E-mail: mmatsui@saitama-med.ac.jp [Department of Microbiology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan)

    2014-01-05

    Virus-like particles (VLPs) are a promising vaccine platform due to the safety and efficiency. However, it is still unclear whether polyomavirus-based VLPs are useful for this purpose. Here, we attempted to evaluate the potential of polyomavirus VLPs for the antiviral vaccine using simian virus 40 (SV40). We constructed chimeric SV40-VLPs carrying an HLA-A{sup ⁎}02:01-restricted, cytotoxic T lymphocyte (CTL) epitope derived from influenza A virus. HLA-A{sup ⁎}02:01-transgenic mice were then immunized with the chimeric SV40-VLPs. The chimeric SV40-VLPs effectively induced influenza-specific CTLs and heterosubtypic protection against influenza A viruses without the need of adjuvants. Because DNase I treatment of the chimeric SV40-VLPs did not disrupt CTL induction, the intrinsic adjuvant property may not result from DNA contaminants in the VLP preparation. In addition, immunization with the chimeric SV40-VLPs generated long-lasting memory CTLs. We here propose that the chimeric SV40-VLPs harboring an epitope may be a promising CTL-based vaccine platform with self-adjuvant properties. - Highlights: • We constructed chimeric SV40-VLPs carrying an influenza virus-derived CTL epitope. • Chimeric SV40-VLPs induce influenza-specific CTLs in mice without adjuvants. • Chimeric SV40-VLPs induce heterosubtypic protection against influenza A viruses. • Chimeric SV40-VLPs induce long-lasting memory CTLs. • Chimeric SV40-VLPs is a promising vaccine platform with self-adjuvant properties.

  16. CHIMERIC WEST NILE/DENGUE VIRUS VACCINE CANDIDATE: PRECLINICAL EVALUATION IN MICE, GEESE, AND MONKEYS FOR SAFETY AND IMMUNOGENICITY

    Science.gov (United States)

    A live attenuated virus vaccine is being developed to protect against West Nile virus (WN) disease in humans. Previously, it was found that chimeric West Nile/dengue viruses (WN/DEN4 and WN/DEN4-delta-30) bearing the membrane precursor and envelope protein genes of WN on a backbone of dengue type 4 ...

  17. The expression and genetic immunization of chimeric fragment of Hantaan virus M and S segments

    International Nuclear Information System (INIS)

    Hemorrhagic fever with renal syndrome (HFRS), which is characterized by severe symptoms and high mortality, is caused by hantavirus. There are still no effective prophylactic vaccines directed to HFRS until now. In this research, we fused expressed G2 fragment of M segment and 0.7 kb fragment of S segment. We expect it could be a candidate vaccine. Chimeric gene G2S0.7 was first expressed in prokaryotic expression system pGEX-4T. After inducing expressed fusion proteins, GST-G2S0.7 was induced and its molecular weight was about 100 kDa. Meanwhile, the fusion protein kept the activity of its parental proteins. Further, BALB/c mice were vaccinated by the chimeric gene. ELISA, cell microculture neutralization test in vitro were used to detect the humoral immune response in immunized BALB/c mice. Lymphocyte proliferation assay was used to detect the cellular immune response. The results showed that the chimeric gene could simultaneously evoke specific antibody against nucleocapsid protein (NP) and glycoprotein (GP). And the immunized mice of every group elicited neutralizing antibodies with different titers. But the titers were low. Lymphocyte proliferation assay results showed that the stimulation indexes of splenocytes of chimeric gene to NP and GP were significantly higher than that of control. It suggested that the chimeric gene of Hantaan virus containing G2 fragment of M segment and 0.7 kb fragment of S segment could directly elicit specific anti-Hantaan virus humoral and cellular immune response in BALB/c mice

  18. Efficient, trans-complementing packaging systems for chimeric, pseudoinfectious dengue 2/yellow fever viruses

    International Nuclear Information System (INIS)

    In our previous studies, we have stated to build a new strategy for developing defective, pseudoinfectious flaviviruses (PIVs) and applying them as a new type of vaccine candidates. PIVs combined the efficiency of live vaccines with the safety of inactivated or subunit vaccines. The results of the present work demonstrate further development of chimeric PIVs encoding dengue virus 2 (DEN2V) glycoproteins and yellow fever virus (YFV)-derived replicative machinery as potential vaccine candidates. The newly designed PIVs have synergistically functioning mutations in the prM and NS2A proteins, which abolish processing of the latter proteins and make the defective viruses capable of producing either only noninfectious, immature and/or subviral DEN2V particles. The PIV genomes can be packaged to high titers into infectious virions in vitro using the NS1-deficient YFV helper RNAs, and both PIVs and helpers can then be passaged as two-component genome viruses at an escalating scale.

  19. Chimeric plant virus particles administered nasally or orally induce systemic and mucosal immune responses in mice

    DEFF Research Database (Denmark)

    Brennan, F.R.; Bellaby, T.; Helliwell, S.M.; Jones, T.D.; Kamstrup, Søren; Dalsgaard, Kristian; Flock, J.I.; Hamilton, W.D.O.

    1999-01-01

    of CVPs to generate antibody at distant mucosal sites. IgG2a and TgG2b were the dominant IgG subclasses in sera to both CPMV and FnBP, demonstrating a bias in the response toward the T helper 1 type. The sera completely inhibited the binding of human fibronectin to the S. aureus FnBP. Oral......The humoral immune responses to the D2 peptide of fibronectin-binding protein B (FnBP) of Staphylococcus aureus, expressed on the plant virus cowpea mosaic virus (CPMV), were evaluated after mucosal delivery to mice. Intranasal immunization of these chimeric virus particles (CVPs), either alone or....... These studies demonstrate for the first time that recombinant plant viruses have potential as mucosal vaccines without the requirement for adjuvant and that the nasal route is most effective for the delivery of these nonreplicating particles....

  20. Enhancement of mucosal immune responses by chimeric influenza HA/SHIV virus-like particles

    International Nuclear Information System (INIS)

    To enhance mucosal immune responses using simian/human immunodeficiency virus-like particles (SHIV VLPs), we have produced novel phenotypically mixed chimeric influenza HA/SHIV VLPs and used them to immunize C57BL/6J mice intranasally. Antibody and cytotoxic T-cell (CTL) responses as well as cytokine production in both systemic and mucosal sites were compared after immunization with SHIV VLPs or chimeric HA/SHIV VLPs. By using enzyme-linked immunosorbent assay (ELISA), the levels of serum IgG and mucosal IgA to the HIV envelope protein (Env) were found to be highest in the group immunized with chimeric HA/SHIV VLPs. Furthermore, the highest titer of serum neutralizing antibody against HIV Env was found with the group immunized with chimeric HA/SHIV VLPs. Analysis of the IgG1/IgG2a ratio indicated that a TH1-oriented immune response resulted from these VLP immunizations. HA/SHIV VLP-immunized mice also showed significantly higher CTL responses than those observed in SHIV VLP-immunized mice. Moreover, a MHC class I restricted T-cell activation ELISPOT assay showed a mixed type of TH1/TH2 cytokines in the HA/SHIV VLP-immunized mice, indicating that the chimeric VLPs can enhance both humoral and cellular immune responses to the HIV Env protein at multiple mucosal and systemic sites. The results indicate that incorporation of influenza HA into heterotypic VLPs may be highly effective for targeting vaccines to mucosal surfaces

  1. Establishment and characterization of a chimeric infectious cDNA clone of classical swine fever virus.

    Science.gov (United States)

    Zhao, T S; Xia, Y H

    2016-01-01

    Classical swine fever virus (CSFV) causes a highly contagious disease among swine that has an important economic impact worldwide. There are two important CSFV strains in China, Shimen and hog cholera lapinized virus (HCLV). Shimen strain is highly virulent while HCLV, also referred to as C-strain, is a live attenuated vaccine strain considered to be one of the most effective and safest live vaccines. In this study, a chimeric infectious cDNA clone of CSFV named pT7SM-c was engineered by replacing the Erns genomic region of an infectious clone of CSFV Shimen strain, pT7SM, with the same region obtained from HCLV. RNA transcripts of pT7SM-c containing an engineered EcoRI site that served as a genetic marker were directly infectious in PK15 cells. The rescued virus vT7SM-c showed similar growth kinetics and cytopathic effect with the parental virus vT7SM in the cells. The chimeric infectious cDNA clone can be used as a practical tool for further studying of the virulence, protein function and pathogenesis of CSFV through genetic manipulation. PMID:27265471

  2. Plant-derived chimeric virus particles for the diagnosis of primary Sjögren syndrome

    Directory of Open Access Journals (Sweden)

    Elisa eTinazzi

    2015-12-01

    Full Text Available Plants are ideal for the production of protein-based nanomaterials because they synthesize and assemble complex multimeric proteins that cannot be expressed efficiently using other platforms. Plant viruses can be thought of as self-replicating proteinaceous nanomaterials generally stable and easily produced in high titers. We used Potato virus X (PVX chimeric virus particles (CVPs and Cowpea mosaic virus (CPMV empty virus-like particles (eVLPs to display a linear peptide (lipo derived from human lipocalin , which is immunodominant in Sjögren’s syndrome (SjS and is thus recognized by autoantibodies in SjS patient serum. These virus-derived nanoparticles (VNPs were thus used to develop a diagnostic assay for SjS based on a direct enzyme linked immunosorbent assay (ELISA format. We found that PVX-lipo formulations were more sensitive than the chemically synthesized immunodominant peptide and equally specific when used to distinguish between healthy individuals and SjS patients. Our novel assay therefore allows the diagnosis of SjS using a simple, low-invasive serum test, contrasting with the invasive labial biopsy required for current tests. Our results demonstrate that nanomaterials based on plant viruses can be used as diagnostic reagents for SjS, and could also be developed for the diagnosis of other diseases.

  3. Plant-Derived Chimeric Virus Particles for the Diagnosis of Primary Sjögren Syndrome.

    Science.gov (United States)

    Tinazzi, Elisa; Merlin, Matilde; Bason, Caterina; Beri, Ruggero; Zampieri, Roberta; Lico, Chiara; Bartoloni, Elena; Puccetti, Antonio; Lunardi, Claudio; Pezzotti, Mario; Avesani, Linda

    2015-01-01

    Plants are ideal for the production of protein-based nanomaterials because they synthesize and assemble complex multimeric proteins that cannot be expressed efficiently using other platforms. Plant viruses can be thought of as self-replicating proteinaceous nanomaterials generally stable and easily produced in high titers. We used Potato virus X (PVX), chimeric virus particles, and Cowpea mosaic virus, empty virus-like particles to display a linear peptide (lipo) derived from human lipocalin, which is immunodominant in Sjögren's syndrome (SjS) and is thus recognized by autoantibodies in SjS patient serum. These virus-derived nanoparticles were thus used to develop a diagnostic assay for SjS based on a direct enzyme linked immunosorbent assay format. We found that PVX-lipo formulations were more sensitive than the chemically synthesized immunodominant peptide and equally specific when used to distinguish between healthy individuals and SjS patients. Our novel assay therefore allows the diagnosis of SjS using a simple, low-invasive serum test, contrasting with the invasive labial biopsy required for current tests. Our results demonstrate that nanomaterials based on plant viruses can be used as diagnostic reagents for SjS, and could also be developed for the diagnosis of other diseases. PMID:26648961

  4. Molecularly engineered live-attenuated chimeric West Nile/dengue virus vaccines protect rhesus monkeys from West Nile virus

    International Nuclear Information System (INIS)

    Two molecularly engineered, live-attenuated West Nile virus (WN) vaccine candidates were highly attenuated and protective in rhesus monkeys. The vaccine candidates are chimeric viruses (designated WN/DEN4) bearing the membrane precursor and envelope protein genes of WN on a backbone of dengue 4 virus (DEN4) with or without a deletion of 30 nucleotides (Δ30) in the 3' noncoding region of DEN4. Viremia in WN/DEN4- infected monkeys was reduced 100-fold compared to that in WN- or DEN4-infected monkeys. WN/DEN4-3'Δ30 did not cause detectable viremia, indicating that it is even more attenuated for monkeys. These findings indicate that chimerization itself and the presence of the Δ30 mutation independently contribute to the attenuation phenotype for nonhuman primates. Despite their high level of attenuation in monkeys, the chimeras induced a moderate-to-high titer of neutralizing antibodies and prevented viremia in monkeys challenged with WN. The more attenuated vaccine candidate, WN/DEN4-3'Δ30, will be evaluated first in our initial clinical studies

  5. A recombinant, chimeric tetravalent dengue vaccine candidate based on a dengue virus serotype 2 backbone.

    Science.gov (United States)

    Osorio, Jorge E; Wallace, Derek; Stinchcomb, Dan T

    2016-04-01

    Dengue fever is caused by infection with one of four dengue virus (DENV) serotypes (DENV-1-4), necessitating tetravalent dengue vaccines that can induce protection against all four DENV. Takeda's live attenuated tetravalent dengue vaccine candidate (TDV) comprises an attenuated DENV-2 strain plus chimeric viruses containing the prM and E genes of DENV-1, -3 and -4 cloned into the attenuated DENV-2 'backbone'. In Phase 1 and 2 studies, TDV was well tolerated by children and adults aged 1.5-45 years, irrespective of prior dengue exposure; mild injection-site symptoms were the most common adverse events. TDV induced neutralizing antibody responses and seroconversion to all four DENV as well as cross-reactive T cell-mediated responses that may be necessary for broad protection against dengue fever. PMID:26635182

  6. An avirulent chimeric Pestivirus with altered cell tropism protects pigs against lethal infection with classical swine fever virus

    International Nuclear Information System (INIS)

    A chimeric Pestivirus was constructed using an infectious cDNA clone of bovine viral diarrhea virus (BVDV) [J. Virol. 70 (1996) 8606]. After deletion of the envelope protein E2-encoding region, the respective sequence of classical swine fever virus (CSFV) strain Alfort 187 was inserted in-frame resulting in plasmid pA/CP7E2alf. After transfection of in vitro-transcribed CP7E2alf RNA, autonomous replication of chimeric RNA in bovine and porcine cell cultures was observed. Efficient growth of chimeric CP7E2alf virus, however, could only be demonstrated on porcine cells, and in contrast to the parental BVDV strain CP7, CP7E2alf only inefficiently infected and propagated in bovine cells. The virulence, immunogenicity, and 'marker vaccine' properties of the generated chimeric CP7E2alf virus were determined in an animal experiment using 27 pigs. After intramuscular inoculation of 1 x 107 TCID50, CP7E2alf proved to be completely avirulent, and neither viremia nor virus transmission to contact animals was observed; however, CSFV-specific neutralizing antibodies were detected from day 11 after inoculation. In addition, sera from all animals reacted positive in an E2-specific CSFV-antibody ELISA, but were negative for CSFV-ERNS-specific antibodies as determined with a CSFV marker ELISA. After challenge infection with highly virulent CSFV strain Eystrup, pigs immunized with CP7E2alf were fully protected against clinical signs of CSFV infection, viremia, and shedding of challenge virus, and almost all animals scored positive in a CSFV marker ELISA. From our results, we conclude that chimeric CP7E2alf may not only serve as a tool for a better understanding of Pestivirus attachment, entry, and assembly, but also represents an innocuous and efficacious modified live CSFV 'marker vaccine'

  7. Chimeric Foot-and-Mouth Disease Viruses: Evaluation of Their Efficacy as Potential Marker Vaccines in Cattle

    Science.gov (United States)

    Previous work in swine has demonstrated that full protection against Foot-and-Mouth Disease (FMD) can be achieved following vaccination with chimeric Foot-and-Mouth Disease Virus (FMDV) vaccines, whereby the VP1 G-H loop has been substituted with a non-homologous alternative. If proven to be effect...

  8. Characterization of the neutralization determinants of equine arteritis virus using recombinant chimeric viruses and site-specific mutagenesis of an infectious cDNA clone

    International Nuclear Information System (INIS)

    We have used an infectious cDNA clone of equine arteritis virus (EAV) and reverse genetics technology to further characterize the neutralization determinants in the GP5 envelope glycoprotein of the virus. We generated a panel of 20 recombinant viruses, including 10 chimeric viruses that each contained the ORF5 (which encodes GP5) of different laboratory, field, and vaccine strains of EAV, a chimeric virus containing the N-terminal ectodomain of GP5 of a European strain of porcine reproductive and respiratory syndrome virus, and 9 mutant viruses with site-specific substitutions in their GP5 proteins. The neutralization phenotype of each recombinant chimeric/mutant strain of EAV was determined with EAV-specific monoclonal antibodies and EAV strain-specific polyclonal equine antisera and compared to that of their parental viruses from which the substituted ORF5 was derived. The data unequivocally confirm that the GP5 ectodomain contains critical determinants of EAV neutralization. Furthermore, individual neutralization sites are conformationally interactive, and the interaction of GP5 with the unglycosylated membrane protein M is likely critical to expression of individual epitopes in neutralizing conformation. Substitution of individual amino acids within the GP5 ectodomain usually resulted in differences in neutralization phenotype of the recombinant viruses, analogous to differences in the neutralization phenotype of field strains of EAV and variants generated during persistent infection of EAV carrier stallions

  9. Chimeric hepatitis B virus (HBV)/hepatitis C virus (HCV) subviral envelope particles induce efficient anti-HCV antibody production in animals pre-immunized with HBV vaccine.

    Science.gov (United States)

    Beaumont, Elodie; Roingeard, Philippe

    2015-02-18

    The development of an effective, affordable prophylactic vaccine against hepatitis C virus (HCV) remains a medical priority. The recently described chimeric HBV-HCV subviral envelope particles could potentially be used for this purpose, as they could be produced by industrial procedures adapted from those established for the hepatitis B virus (HBV) vaccine. We show here, in an animal model, that pre-existing immunity acquired through HBV vaccination does not influence the immunogenicity of the HCV E2 protein presented by these chimeric particles. Thus, these chimeric HBV-HCV subviral envelope particles could potentially be used as a booster in individuals previously vaccinated against HBV, to induce protective immunity to HCV. PMID:25596457

  10. A novel chimeric adenoassociated virus 2/human bocavirus 1 parvovirus vector efficiently transduces human airway epithelia.

    Science.gov (United States)

    Yan, Ziying; Keiser, Nicholas W; Song, Yi; Deng, Xuefeng; Cheng, Fang; Qiu, Jianming; Engelhardt, John F

    2013-12-01

    Human bocavirus virus-1 (HBoV1), a newly discovered autonomous parvovirus with a 5,500 nt genome, efficiently infects human-polarized airway epithelia (HAE) from the apical membrane. We hypothesized that the larger genome and high airway tropism of HBoV1 would be ideal for creating a viral vector for lung gene therapy. To this end, we successfully generated recombinant HBoV1 (rHBoV1) from an open reading frames-disrupted rHBoV1 genome that efficiently transduces HAE from the apical surface. We next evaluated whether HBoV1 capsids could package oversized rAAV2 genomes. These studies created a rAAV2/HBoV1 chimeric virus (5.5 kb genome) capable of apically transducing HAE at 5.6- and 70-fold greater efficiency than rAAV1 or rAAV2 (4.7-kb genomes), respectively. Molecular studies demonstrated that viral uptake from the apical surface was significantly greater for rAAV2/HBoV1 than for rAAV2 or rAAV1, and that polarization of airway epithelial cells was required for HBoV1 capsid-mediated gene transfer. Furthermore, rAAV2/HBoV1-CFTR virus containing the full-length cystic fibrosis transmembrane conductance regulator (CFTR) gene coding sequence and the strong CBA promoter efficiently corrected CFTR-dependent chloride transport in cystic fibrosis (CF) HAE. In summary, using the combined advantages of AAV and HBoV1, we have developed a novel and promising viral vector for CF lung gene therapy and also potentially HBoV1 vaccine development. PMID:23896725

  11. PRODUCTION IN PICHIA PASTORIS AND CHARACTERIZATION OF GENETIC ENGINEERED CHIMERIC HBV/HEV VIRUS-LIKE PARTICLES

    Institute of Scientific and Technical Information of China (English)

    Hong-zhao Li; Hong-ying Gang; Qiang-ming Sun; Xiao Liu; Yan-bing Ma; Mao-sheng Sun; Chang-bai Dai

    2004-01-01

    Objective To investigate the presentation of a neutralization epitope-containing peptide antigen of hepatitis E virus (HEV)on chimeric virus-like particles (VLPs) of hepatitis B surface antigen (HBsAg).Methods The gene fragment corresponding to amino acids (aa) 551-607 (HEnAg) of HEV capsid protein, which contains the only neutralization epitope identified to date, was fused via a synthetic glycine linker in frame with the gene of HBsAg.The resulted fusion gene was then integrated through transformation into the genome of Pichiapastoris under the control of a methanol-induced alcohol oxidase 1 (A OX 1) promoter and expressed intracellularly. The expression products in the soluble cell extracts were characterized by Western blot, ELISA, CsCl density gradient analysis, and electron microscopic visualization.Results The novel fusion protein incorporating HBsAg and the neutralization epitope-containing HEnAg was expressed successfully in Pichiapastoris with an expected molecular weight of approximately 32 kD. It was found to possess the ability to assemble into chimeric HBV/HEV VLPs with immunological, physical and morphological characteristics akin to HBsAg particles. Not only did the chimeric VLPs show high activity levels in a HBsAg particle-specific ELISA but they were also strongly immunoreactive with hepatitis E (HE) positive human serum in a HEV specific ELISA, indicating that HEnAg peptide fragments were exposed on VLP surfaces and would be expected to be readily accessible by cells and molecules of the immune system. Similarity between chimeric VLPs to highly immunogenic HBsAg particles may confer good immunogenicity on surface-displayed HEnAg.Conclusion The chimeric HBV/HEV VLPs produced in this study may have potential to be a recombinant HBV/HEV bivalent vaccine candidate.

  12. Identification of two amino acids within E2 important for the pathogenicity of chimeric classical swine fever virus.

    Science.gov (United States)

    Wu, Rui; Li, Ling; Zhao, Yu; Tu, Jun; Pan, Zishu

    2016-01-01

    Our previous study demonstrated that a chimeric classical swine fever virus (CSFV) vSM/CE2 containing the E2 gene of the vaccine C-strain on the genetic background of the virulent CSFV strain Shimen (vSM) was attenuated in swine but reversed to virulence after serial passages in PK15 cells. To investigate the molecular basis of the pathogenicity, the genome of the 11th passage vSM/CE2 variant (vSM/CE2-p11) was sequenced, and two amino acid mutations, T745I and M979K, within E2 of vSM/CE2-p11 were observed. Based on reverse genetic manipulation of the chimeric cDNA clone pSM/CE2, the mutated viruses vSM/CE2/T745I, vSMCE2/M979K and vSM/CE2/T745I;M979K were rescued. The data from infection of pigs demonstrated that the M979K amino acid substitution was responsible for pathogenicity. Studies in vitro indicated that T745I and M979K increased infectious virus production and replication. Our results indicated that two residues located at sites 745 and 979 within E2 play a key role in determining the replication in vitro and pathogenicity in vivo of chimeric CSFV vSM/CE2. PMID:26454191

  13. Chimeric human parainfluenza virus bearing the Ebola virus glycoprotein as the sole surface protein is immunogenic and highly protective against Ebola virus challenge

    International Nuclear Information System (INIS)

    We generated a new live-attenuated vaccine against Ebola virus (EBOV) based on a chimeric virus HPIV3/ΔF-HN/EboGP that contains the EBOV glycoprotein (GP) as the sole transmembrane envelope protein combined with the internal proteins of human parainfluenza virus type 3 (HPIV3). Electron microscopy analysis of the virus particles showed that they have an envelope and surface spikes resembling those of EBOV and a particle size and shape resembling those of HPIV3. When HPIV3/ΔF-HN/EboGP was inoculated via apical surface of an in vitro model of human ciliated airway epithelium, the virus was released from the apical surface; when applied to basolateral surface, the virus infected basolateral cells but did not spread through the tissue. Following intranasal (IN) inoculation of guinea pigs, scattered infected cells were detected in the lungs by immunohistochemistry, but infectious HPIV3/ΔF-HN/EboGP could not be recovered from the lungs, blood, or other tissues. Despite the attenuation, the virus was highly immunogenic, and a single IN dose completely protected the animals against a highly lethal intraperitoneal challenge of guinea pig-adapted EBOV

  14. Virus-Like Particles of Chimeric Recombinant Porcine Circovirus Type 2 as Antigen Vehicle Carrying Foreign Epitopes

    OpenAIRE

    2014-01-01

    Virus-like particles (VLPs) of chimeric porcine circovirus type 2 (PCV2) were generated by replacing the nuclear localization signal (NLS; at 1–39 aa) of PCV2 capsid protein (Cap) with classical swine fever virus (CSFV) T-cell epitope (1446–1460 aa), CSFV B-cell epitope (693–716 aa) and CSFV T-cell epitope conjugated with B-cell epitope. The recombinant proteins were expressed using the baculovirus expression system and detected by immunoblotting and indirect immunofluorescence assay. The ab...

  15. Functionality of Chimeric E2 Glycoproteins of BVDV and CSFV in Virus Replication

    Directory of Open Access Journals (Sweden)

    H.G.P. van Gennip

    2008-01-01

    Full Text Available An intriguing difference between the E2 glycoprotein of CSFV and the other groups of pestiviruses (nonCSFV is a lack of two cysteine residues on positions cysteine 751 and 798. Other groups of pestivirus are not restricted to one species as swine, whereas CSFV is restricted to swine and wild boar. We constructed chimeric CSFV/BVDV E2 genes based on a 2D model of E2 proposed by van Rijn et al. (van Rijn et al. 1994, J Virol 68, 3934–42 and confirmed their expression by immunostaining of plasmid-transfected SK6 cells. No equivalents for the antigenic units B/C and A were found on E2 of BVDVII. This indicates major structural differences in E2. However, the immunodominant BVDVII domain A, containing epitopes with essential amino acids between position 760–764, showed to be dependent on the presence of the region defined by amino acids 684 to 796. As for the A domain of CSFV, the BVDVII A-like domain seemed to function as a separate unit. These combined domains in E2 proved to be the only combination which was functional in viral background of CSFV C-strain. The fitness of this virus (vfl c36BVDVII 684–796 seemed to be reduced compared to vfl c9 (with the complete antigenic region of BVDVII.

  16. Replication of chimeric tobacco mosaic viruses which carry heterologous combinations of replicase genes and 3' noncoding regions.

    Science.gov (United States)

    Ishikawa, M; Meshi, T; Watanabe, Y; Okada, Y

    1988-05-01

    Three tobacco mosaic virus (TMV)-L (tomato strain)-derived chimeras, designated OL1, LG11, or LK31, were constructed by replacing the 3' noncoding region with the corresponding sequence of TMV-OM (common strain), cucumber green mottle mosaic virus (CGMMV), or TMV-Cc (cowpea strain), respectively. The genomic RNAs of TMV-L, -OM, and CGMMV carry histidine-accepting tRNA-like structures at their 3' termini, while the genome of TMV-Cc accepts valine. The three chimeric viruses were able to multiply in both tobacco protoplasts and plants. Multiplication of OL1 in protoplasts was similar to that of the parental strain, L, but in the cases of LG11 and LK31 multiplication was decreased. Sequence analyses of progeny RNAs revealed that viruses with chimeric sequences propagated. These data suggested that TMV-L replicase recognizes the 3' terminal structures of TMV-OM, CGMMV, and TMV-Cc and can initiate minus-strand RNA synthesis. The relationship between the virus-coded component(s) of TMV replicase and the 3' terminal region may not be so stringent. PMID:2452515

  17. Chimeric Rabies Virus-Like Particles Containing Membrane-Anchored GM-CSF Enhances the Immune Response against Rabies Virus

    Directory of Open Access Journals (Sweden)

    Hongtao Kang

    2015-03-01

    Full Text Available Rabies remains an important public health threat in most developing countries. To develop a more effective and safe vaccine against rabies, we have constructed a chimeric rabies virus-like particle (VLP, which containing glycoprotein (G and matrix protein (M of rabies virus (RABV Evelyn-Rokitnicki-Abelseth (ERA strain, and membrane-anchored granulocyte-macrophage colony-stimulating factor (GM-CSF, and it was named of EVLP-G. The immunogenicity and protective efficacy of EVLP-G against RABV were evaluated by intramuscular administration in a mouse model. The EVLP-G was successfully produced in insect cells by coinfection with three recombinant baculoviruses expressing G, M, and GM-CSF, respectively. The membrane-anchored GM-CSF possesses a strong adjuvant activity. More B cells and dendritic cells (DCs were recruited and/or activated in inguinal lymph nodes in mice immunized with EVLP-G. EVLP-G was found to induce a significantly increased RABV-specific virus-neutralizing antibody and elicit a larger and broader antibody subclass responses compared with the standard rabies VLP (sRVLP, consisting of G and M. The EVLP-G also elicited significantly more IFN-γ- or IL-4-secreting CD4+ and CD8+ T cells than the sRVLP. Moreover, the immune responses induced by EVLP-G protect all vaccinated mice from lethal challenge with RABV. These results suggest that EVLP-G has the potential to be developed as a novel vaccine candidate for the prevention and control of animal rabies.

  18. Chimeric rabies virus-like particles containing membrane-anchored GM-CSF enhances the immune response against rabies virus.

    Science.gov (United States)

    Kang, Hongtao; Qi, Yinglin; Wang, Hualei; Zheng, Xuexing; Gao, Yuwei; Li, Nan; Yang, Songtao; Xia, Xianzhu

    2015-03-01

    Rabies remains an important public health threat in most developing countries. To develop a more effective and safe vaccine against rabies, we have constructed a chimeric rabies virus-like particle (VLP), which containing glycoprotein (G) and matrix protein (M) of rabies virus (RABV) Evelyn-Rokitnicki-Abelseth (ERA) strain, and membrane-anchored granulocyte-macrophage colony-stimulating factor (GM-CSF), and it was named of EVLP-G. The immunogenicity and protective efficacy of EVLP-G against RABV were evaluated by intramuscular administration in a mouse model. The EVLP-G was successfully produced in insect cells by coinfection with three recombinant baculoviruses expressing G, M, and GM-CSF, respectively. The membrane-anchored GM-CSF possesses a strong adjuvant activity. More B cells and dendritic cells (DCs) were recruited and/or activated in inguinal lymph nodes in mice immunized with EVLP-G. EVLP-G was found to induce a significantly increased RABV-specific virus-neutralizing antibody and elicit a larger and broader antibody subclass responses compared with the standard rabies VLP (sRVLP, consisting of G and M). The EVLP-G also elicited significantly more IFN-γ- or IL-4-secreting CD4+ and CD8+ T cells than the sRVLP. Moreover, the immune responses induced by EVLP-G protect all vaccinated mice from lethal challenge with RABV. These results suggest that EVLP-G has the potential to be developed as a novel vaccine candidate for the prevention and control of animal rabies. PMID:25768031

  19. Replication of a chimeric origin containing elements from Epstein-Barr virus ori P and bovine papillomavirus minimal origin.

    Science.gov (United States)

    Kivimäe, S; Allikas, A; Kurg, R; Ustav, M

    2001-05-01

    The bovine papillomavirus E2 protein is a multifunctional protein that activates viral transcription, co-operates in initiation of viral DNA replication, and is required for long-term episomal maintenance of viral genomes. The EBNA1 protein of Epstein-Barr virus is required for synthesis and maintenance of Epstein-Barr virus genomes. Both viral proteins act through direct interactions with their respective DNA sequences in their origins of replication. The chimeric protein E2:EBNA1, which consists of an transactivation domain of E2 and DNA binding domain of EBNA1 supported the replication of the chimeric origin that contained EBNA1 binding sites in place of the E2 binding sites principally as full-length E2 did in the case of papillomavirus minimal origin. This indicates that the chimeric protein E2:EBNA1 is competent to assemble a replication complex similar to the E2 protein. These data confirm the earlier observations that the only part of E2 specifically required for its activity in replication is the N-terminal activation domain and the function of the DNA binding domain of E2 in the initiation of replication is to tether the transactivation domain of E2 to the origin of replication. PMID:11311423

  20. Expression and immunoactivity of chimeric particulate antigens of receptor binding site-core antigen of hepatitis B virus

    Institute of Scientific and Technical Information of China (English)

    Hai-Jie Yang; Ning-Shao Xia; Min Chen; Tong Cheng; Shui-Zhen He; Shao-Wei Li; Bao-Quan Guan; Zi-Heng Zhu; Ying Gu; Jun Zhang

    2005-01-01

    AIM: To improve the immunogenicity of receptor binding site of hepatitis B virus (HBV) on preS1 antigen using HBV core antigen as an immuno-carrier.METHODS: One to 6 tandem copies of HBV preS1 (21-47)fragment were inserted into HBcAg at the sites of aa 78 and 82, and expressed in E. coli. ELISA, Western blot and animal immunization were used to analyze the antigenicity and immmunogenicity of purified particulate antigens. The ability to capture HBV by antibodies elicited by chimeric partides was detected with immuno-capture PCR.RESULTS: Recombinant antigens CⅠ, CⅡ, CⅢ carrying 1-3 copies of HBV preS1 (21-47) individually could form viruslike particles (VLPs), similar to HBcAg in morphology. But recombinant antigens carrying 4-6 copies of HBV preS1 (21-47) were poorly expressed in E.coli. Chimeric antigens were lacking of immunoreactivity with anti-HBc monoclonal antibodies (McAbs), but still reserved good immunoreactivity with anti-HBe McAbs. CⅠ, CⅡ, CⅢ could strongly react with anti-preS1 McAb, suggesting that preS1 (21-47) fragment was well exposed on the surface of chimeric VLPs. Three chimeric VLP antigens (CⅠ, CⅡ and CⅢ) could stimulate mice to produce high-level antibody responses, and their immunogenicity was stronger than non-particulate antigen 21-47*6, containing 6 copies of preS1 (21-47). Mouse antibodies to CⅠ, CⅡ and CⅢ were able to capture HBV virions in immuno-capture PCR assay in vitro.CONCLUSION: Chimeric particulate antigens of receptor binding site-core antigen of HBV can elicit strong antibody responses to preS1. They have a potential to be developed into prophylactic or therapeutic vaccines against HBV infection.

  1. A Bivalent, Chimeric Rabies Virus Expressing Simian Immunodeficiency Virus Envelope Induces Multifunctional Antibody Responses.

    Science.gov (United States)

    Dunkel, Amber; Shen, Shixue; LaBranche, Celia C; Montefiori, David; McGettigan, James P

    2015-11-01

    We previously showed that a matrix (M) gene-deleted rabies virus (RABV)-based vaccine (RABV-ΔM) is highly immunogenic and induces potent B cell responses in the context of RABV infection. We speculated that RABV-ΔM expressing HIV proteins would also induce potent B cell responses against HIV antigens. As a prerequisite to future studies in nonhuman primates, we completed immunogenicity studies in mice to confirm the ability of RABV-ΔM to induce polyfunctional B cell responses in the context of HIV. To that end, the envelope protein from the mac239 strain of SIV (SIVmac239Env) was cloned into RABV-ΔM, resulting in RABV-ΔM-Env. Infectious virus was recovered following standard methods and propagated on baby hamster kidney cells stably expressing RABV M [>10(7) focus forming units (ffu)/ml]. Western blot analysis of cell lysates or of purified virions confirmed Env expression on the surface of infected cells and within virus particles, respectively. Positive neutralization activity against a neutralization-sensitive SIV strain and to a lesser extent against a neutralization-resistant SIV strain was detected in mice after a single intramuscular inoculation with RABV-ΔM-Env. The quality, but not quantity, of the antibody response was enhanced via boosting with recombinant gp130 or RABV-ΔM-Env as measured by an increase in antibody avidity and a skewing toward a Th1-type antibody response. We also show that an intradermal inoculation induces higher antibodies than an intramuscular or intranasal inoculation. An intradermal inoculation of RABV-ΔM-Env followed by a boost inoculation with recombinant gp130 produced anti-SIV antibodies with neutralizing and nonneutralizing antibody (nNAb) effector functions. Together, RABV-ΔM-Env induces B cells to secrete antibodies against SIV with the potential to clear both "free" and cell-associated virus. Strategies capable of eliciting both NAbs as well as nNAbs might help to improve the efficacy of HIV-1 vaccines. PMID

  2. Chimeric viruses containing the N-terminal ectodomains of GP5 and M proteins of porcine reproductive and respiratory syndrome do not change the cellular tropism of equine arteritis virus

    Science.gov (United States)

    Equine arteritis virus (EAV) and porcine reproductive and respiratory syndrome virus (PRRSV) are members of family Arteriviridae; they share many biological properties but differ significantly in cellular tropism. Using an infectious cDNA clone of EAV, we engineered a panel of six chimeric viruses b...

  3. A transgenic plant cell-suspension system for expression of epitopes on chimeric Bamboo mosaic virus particles.

    Science.gov (United States)

    Muthamilselvan, Thangarasu; Lee, Chin-Wei; Cho, Yu-Hsin; Wu, Feng-Chao; Hu, Chung-Chi; Liang, Yu-Chuan; Lin, Na-Sheng; Hsu, Yau-Heiu

    2016-01-01

    We describe a novel strategy to produce vaccine antigens using a plant cell-suspension culture system in lieu of the conventional bacterial or animal cell-culture systems. We generated transgenic cell-suspension cultures from Nicotiana benthamiana leaves carrying wild-type or chimeric Bamboo mosaic virus (BaMV) expression constructs encoding the viral protein 1 (VP1) epitope of foot-and-mouth disease virus (FMDV). Antigens accumulated to high levels in BdT38 and BdT19 transgenic cell lines co-expressing silencing suppressor protein P38 or P19. BaMV chimeric virus particles (CVPs) were subsequently purified from the respective cell lines (1.5 and 2.1 mg CVPs/20 g fresh weight of suspended biomass, respectively), and the resulting CVPs displayed VP1 epitope on the surfaces. Guinea pigs vaccinated with purified CVPs produced humoral antibodies. This study represents an important advance in the large-scale production of immunopeptide vaccines in a cost-effective manner using a plant cell-suspension culture system. PMID:25879277

  4. Virus-Specific Read-Through Codon Preference Affects Infectivity of Chimeric Cucumber Green Mottle Mosaic Viruses Displaying a Dengue Virus Epitope

    Directory of Open Access Journals (Sweden)

    Pak-Guan Teoh

    2009-01-01

    Full Text Available A Cucumber green mottle mosaic virus (CGMMV was used to present a truncated dengue virus type 2 envelope (E protein binding region from amino acids 379 to 423 (EB4. The EB4 gene was inserted at the terminal end of the CGMMV coat protein (CP open reading frame (ORF. Read-through sequences of TMV or CGMMV, CAA-UAG-CAA-UUA, or AAA-UAG-CAA-UUA were, respectively, inserted in between the CP and the EB4 genes. The chimeric clones, pRT, pRG, and pCG+FSRTRE, were transcribed into full-length capped recombinant CGMMV transcripts. Only constructs with the wild-type CGMMV read-through sequence yielded infectious viruses following infection of host plant, muskmelon (Cucumis melo leaves. The ratio of modified to unmodified CP for the read-through expression clone developed was also found to be approximately 1:1, higher than what has been previously reported. It was also observed that infectivity was not affected by differences in pI between the chimera and its wild counterpart. Analysis of recombinant viruses after 21-days-postinculation (dpi revealed that deletions occurred resulting in partial reversions of the viral population to near wild type and suggesting that this would be the limiting harvest period for obtaining true to type recombinants with this construct.

  5. A Chimeric HIV-1 gp120 Fused with Vaccinia Virus 14K (A27) Protein as an HIV Immunogen

    OpenAIRE

    Vijayan, Aneesh; García-Arriaza, Juan; C. Raman, Suresh; Conesa, José Javier; Chichón, Francisco Javier; Santiago, César; Sorzano, Carlos Óscar S.; Carrascosa, José L.; Esteban, Mariano

    2015-01-01

    In the HIV vaccine field, there is a need to produce highly immunogenic forms of the Env protein with the capacity to trigger broad B and T-cell responses. Here, we report the generation and characterization of a chimeric HIV-1 gp120 protein (termed gp120-14K) by fusing gp120 from clade B with the vaccinia virus (VACV) 14K oligomeric protein (derived from A27L gene). Stable CHO cell lines expressing HIV-1 gp120-14K protein were generated and the protein purified was characterized by size excl...

  6. Chimeric newcastle disease virus protects chickens against avian influenza in the presence of maternally derived NDV immunity.

    Directory of Open Access Journals (Sweden)

    Constanze Steglich

    Full Text Available Newcastle disease virus (NDV, an avian paramyxovirus type 1, is a promising vector for expression of heterologous proteins from a variety of unrelated viruses including highly pathogenic avian influenza virus (HPAIV. However, pre-existing NDV antibodies may impair vector virus replication, resulting in an inefficient immune response against the foreign antigen. A chimeric NDV-based vector with functional surface glycoproteins unrelated to NDV could overcome this problem. Therefore, an NDV vector was constructed which carries the fusion (F and hemagglutinin-neuraminidase (HN proteins of avian paramyxovirus type 8 (APMV-8 instead of the corresponding NDV proteins in an NDV backbone derived from the lentogenic NDV Clone 30 and a gene expressing HPAIV H5 inserted between the F and HN genes. After successful virus rescue by reverse genetics, the resulting chNDVFHN PMV8H5 was characterized in vitro and in vivo. Expression and virion incorporation of the heterologous proteins was verified by Western blot and electron microscopy. Replication of the newly generated recombinant virus was comparable to parental NDV in embryonated chicken eggs. Immunization with chNDVFHN PMV8H5 stimulated full protection against lethal HPAIV infection in chickens without as well as with maternally derived NDV antibodies. Thus, tailored NDV vector vaccines can be provided for use in the presence or absence of routine NDV vaccination.

  7. Polyclonal immunoglobulins from a chronic hepatitis C virus patient protect human liver-chimeric mice from infection with a homologous hepatitis C virus strain

    DEFF Research Database (Denmark)

    Vanwolleghem, Thomas; Bukh, Jens; Meuleman, Philip;

    2008-01-01

    chimeric mice, the inoculum was pre-incubated in vitro at an IgG concentration normally observed in humans. Conclusion: Polyclonal IgG from a patient with a long-standing HCV infection not only displays neutralizing activity in vitro using the HCVpp system, but also conveys sterilizing immunity toward the......The role of the humoral immune response in the natural course of hepatitis C virus (HCV) infection is widely debated. Most chronically infected patients have immunoglobulin G (IgG) antibodies capable of neutralizing HCV pseudoparticles (HCVpp) in vitro. It is, however, not clear whether these Ig......G can prevent a de novo HCV infection in vivo and contribute to the control of viremia in infected individuals. We addressed this question with homologous in vivo protection studies in human liver-urokinase-type plasminogen activator (uPA)(+/+) severe combined immune deficient (SCID) mice. Chimeric mice...

  8. Virus-Like Particles of Chimeric Recombinant Porcine Circovirus Type 2 as Antigen Vehicle Carrying Foreign Epitopes

    Directory of Open Access Journals (Sweden)

    Huawei Zhang

    2014-12-01

    Full Text Available Virus-like particles (VLPs of chimeric porcine circovirus type 2 (PCV2 were generated by replacing the nuclear localization signal (NLS; at 1–39 aa of PCV2 capsid protein (Cap with classical swine fever virus (CSFV T-cell epitope (1446–1460 aa, CSFV B-cell epitope (693–716 aa and CSFV T-cell epitope conjugated with B-cell epitope. The recombinant proteins were expressed using the baculovirus expression system and detected by immunoblotting and indirect immunofluorescence assay. The abilities to form PCV2 VLPs were confirmed by transmission electron microscopy. Immunogenicities of the three recombinant proteins were evaluated in mice. Our Results indicated that Cap protein NLS deletion or substitution with CSFV epitopes did not affect the VLPs assembly. Three chimeric Cap proteins could form VLPs and induce efficient humoral and cellular immunity against PCV2 and CSFV in mice. Results show that PCV2 VLPs can be used as an efficient antigen carrier for delivery of foreign epitopes, and a potential novel vaccine.

  9. Virus-like particles of chimeric recombinant porcine circovirus type 2 as antigen vehicle carrying foreign epitopes.

    Science.gov (United States)

    Zhang, Huawei; Qian, Ping; Liu, Lifeng; Qian, Suhong; Chen, Huanchun; Li, Xiangmin

    2014-12-01

    Virus-like particles (VLPs) of chimeric porcine circovirus type 2 (PCV2) were generated by replacing the nuclear localization signal (NLS; at 1-39 aa) of PCV2 capsid protein (Cap) with classical swine fever virus (CSFV) T-cell epitope (1446-1460 aa), CSFV B-cell epitope (693-716 aa) and CSFV T-cell epitope conjugated with B-cell epitope. The recombinant proteins were expressed using the baculovirus expression system and detected by immunoblotting and indirect immunofluorescence assay. The abilities to form PCV2 VLPs were confirmed by transmission electron microscopy. Immunogenicities of the three recombinant proteins were evaluated in mice. Our Results indicated that Cap protein NLS deletion or substitution with CSFV epitopes did not affect the VLPs assembly. Three chimeric Cap proteins could form VLPs and induce efficient humoral and cellular immunity against PCV2 and CSFV in mice. Results show that PCV2 VLPs can be used as an efficient antigen carrier for delivery of foreign epitopes, and a potential novel vaccine. PMID:25490764

  10. Evaluation of Trichodysplasia Spinulosa-Associated Polyomavirus Capsid Protein as a New Carrier for Construction of Chimeric Virus-Like Particles Harboring Foreign Epitopes

    Directory of Open Access Journals (Sweden)

    Alma Gedvilaite

    2015-07-01

    Full Text Available Recombinant virus-like particles (VLPs represent a promising tool for protein engineering. Recently, trichodysplasia spinulosa-associated polyomavirus (TSPyV viral protein 1 (VP1 was efficiently produced in yeast expression system and shown to self-assemble to VLPs. In the current study, TSPyV VP1 protein was exploited as a carrier for construction of chimeric VLPs harboring selected B and T cell-specific epitopes and evaluated in comparison to hamster polyomavirus VP1 protein. Chimeric VLPs with inserted either hepatitis B virus preS1 epitope DPAFR or a universal T cell-specific epitope AKFVAAWTLKAAA were produced in yeast Saccharomyces cerevisiae. Target epitopes were incorporated either at the HI or BC loop of the VP1 protein. The insertion sites were selected based on molecular models of TSPyV VP1 protein. The surface exposure of the insert positions was confirmed using a collection of monoclonal antibodies raised against the intact TSPyV VP1 protein. All generated chimeric proteins were capable to self-assemble to VLPs, which induced a strong immune response in mice. The chimeric VLPs also activated dendritic cells and T cells as demonstrated by analysis of cell surface markers and cytokine production profiles in spleen cell cultures. In conclusion, TSPyV VP1 protein represents a new potential carrier for construction of chimeric VLPs harboring target epitopes.

  11. Protective Efficacy of a Single Immunization of a Chimeric Adenovirus Vector-Based Vaccine against Simian Immunodeficiency Virus Challenge in Rhesus Monkeys▿

    OpenAIRE

    Barouch, Dan H.; Liu, Jinyan; Lynch, Diana M; O'Brien, Kara L.; La Porte, Annalena; Simmons, Nathaniel L.; Riggs, Ambryice M.; Clark, Sarah; Abbink, Peter; Montefiori, David C.; Landucci, Gary; Forthal, Donald N.; Self, Steven G.; Carville, Angela; Mansfield, Keith

    2009-01-01

    Rare serotype and chimeric recombinant adenovirus (rAd) vectors that evade anti-Ad5 immunity are currently being evaluated as potential vaccine vectors for human immunodeficiency virus type 1 and other pathogens. We have recently reported that a heterologous rAd prime-boost regimen expressing simian immunodeficiency virus (SIV) Gag afforded durable partial immune control of an SIV challenge in rhesus monkeys. However, single-shot immunization may ultimately be preferable for global vaccine de...

  12. Human glial chimeric mice reveal astrocytic dependence of JC virus infection

    DEFF Research Database (Denmark)

    Kondo, Yoichi; Windrem, Martha S; Zou, Lisa;

    2014-01-01

    with humanized white matter by engrafting human glial progenitor cells (GPCs) into neonatal immunodeficient and myelin-deficient mice. Intracerebral delivery of JCV resulted in infection and subsequent demyelination of these chimeric mice. Human GPCs and astrocytes were infected more readily than...... oligodendrocytes, and viral replication was noted primarily in human astrocytes and GPCs rather than oligodendrocytes, which instead expressed early viral T antigens and exhibited apoptotic death. Engraftment of human GPCs in normally myelinated and immunodeficient mice resulted in humanized white matter that was...... chimeric for human astrocytes and GPCs. JCV effectively propagated in these mice, which indicates that astroglial infection is sufficient for JCV spread. Sequencing revealed progressive mutation of the JCV capsid protein VP1 after infection, suggesting that PML may evolve with active infection. These...

  13. Pathogenesis of Alfalfa mosaic virus in Soybean (Glycine max) and Expression of Chimeric Rabies Peptide in Virus-Infected Soybean Plants.

    Science.gov (United States)

    Fleysh, N; Deka, D; Drath, M; Koprowski, H; Yusibov, V

    2001-10-01

    ABSTRACT Infection of soybean (Glycine max) plants inoculated with particles of Alfalfa mosaic virus (AlMV) isolate 425 at 12 days after germination was monitored throughout the life cycle of the plant (vegetative growth, flowering, seed formation, and seed maturation) by western blot analysis of tissue samples. At 8 to 10 days after inoculation, the upper uninoculated leaves showed symptoms of virus infection and accumulation of viral coat protein (CP). Virus CP was detectable in leaves, stem, roots, seedpods, and seed coat up to 45 days postinoculation (dpi), but only in the seedpod and seed coat at 65 dpi. No virus accumulation was detected in embryos and cotyledons at any time during infection, and no seed transmission of virus was observed. Soybean plants inoculated with recombinant AlMV passaged from upper uninoculated leaves of infected plants showed accumulation of full-length chimeric AlMV CP containing rabies antigen in systemically infected leaves and seed coat. These results suggest the potential usefulness of plants and plant viruses as vehicles for producing proteins of biomedical importance in a safe and inexpensive manner. Moreover, even the soybean seed coat, treated as waste tissue during conventional processing for oil and other products, may be utilized for the expression of value-added proteins. PMID:18944120

  14. Preclinical and Clinical Development of a YFV 17 D-Based Chimeric Vaccine against West Nile Virus

    Directory of Open Access Journals (Sweden)

    Gustavo H. Dayan

    2013-12-01

    Full Text Available Substantial success has been achieved in the development and implementation of West Nile (WN vaccines for horses; however, no human WN vaccines are approved. This review focuses on the construction, pre-clinical and clinical characterization of ChimeriVax-WN02 for humans, a live chimeric vaccine composed of a yellow fever (YF 17D virus in which the prM-E envelope protein genes are replaced with the corresponding genes of the WN NY99 virus. Pre-clinical studies demonstrated that ChimeriVax-WN02 was significantly less neurovirulent than YF 17D in mice and rhesus and cynomolgus monkeys. The vaccine elicited neutralizing antibody titers after inoculation in hamsters and monkeys and protected immunized animals from lethal challenge including intracerebral inoculation of high dose of WN NY99 virus. Safety, viremia and immunogenicity of ChimeriVax-WN02 were assessed in one phase I study and in two phase II clinical trials. No safety signals were detected in the three clinical trials with no remarkable differences in incidence of adverse events (AEs between vaccine and placebo recipients. Viremia was transient and the mean viremia levels were low. The vaccine elicited strong and durable neutralizing antibody and cytotoxic T cell responses. WN epidemiology impedes a classical licensure pathway; therefore, innovative licensure strategies should be explored.

  15. Effect of natural and chimeric haemagglutinin genes on influenza A virus replication in baby hamster kidney cells.

    Science.gov (United States)

    van Wielink, R; Harmsen, M M; Martens, D E; de Leeuw, O S; Peeters, B P H; Wijffels, R H; Moormann, R J M

    2012-12-31

    Baby hamster kidney (BHK21) cells are used to produce vaccines against various viral veterinary diseases, including rabies and foot-and-mouth-disease. Although particular influenza virus strains replicate efficiently in BHK21 cells the general use of these cells for influenza vaccine production is prohibited by the poor replication of most strains, including model strain A/PR/8/34 [H1N1] (PR8). We now show that in contrast to PR8, the related strain A/WSN/33 [H1N1] (WSN) replicates efficiently in BHK21 cells. This difference is determined by the haemagglutinin (HA) protein since reciprocal reassortant viruses with swapped HAs behave similarly with respect to growth on BHK21 cells as the parental virus from which their HA gene is derived. The ability or inability of six other influenza virus strains to grow on BHK21 cells appears to be similarly dependent on the nature of the HA gene since reassortant PR8 viruses containing the HA of these strains grow to similar titres as the parental virus from which the HA gene was derived. However, the growth to low titres of a seventh influenza strain was not due to the nature of the HA gene since a reassortant PR8 virus containing this HA grew efficiently on BHK21 cells. Taken together, these results suggest that the HA gene often primarily determines influenza replication efficiency on BHK21 cells but that in some strains other genes are also involved. High virus titres could be obtained with reassortant PR8 strains that contained a chimeric HA consisting of the HA1 domain of PR8 and the HA2 domain of WSN. HA1 contains most antigenic sites and is therefore important for vaccine efficacy. This method of producing the HA1 domain as fusion to a heterologous HA2 domain could possibly also be used for the production of HA1 domains of other viruses to enable the use of BHK21 cells as a generic platform for veterinary influenza vaccine production. PMID:23079079

  16. Novel chimeric foot-and-mouth disease virus-like particles harboring serotype O VP1 protect guinea pigs against challenge.

    Science.gov (United States)

    Li, Haitao; Li, Zhiyong; Xie, Yinli; Qin, Xiaodong; Qi, Xingcai; Sun, Peng; Bai, Xingwen; Ma, Youji; Zhang, Zhidong

    2016-02-01

    Foot-and-mouth disease is a highly contagious, acute viral disease of cloven-hoofed animal species causing severe economic losses worldwide. Among the seven serotypes of foot-and-mouth disease virus (FMDV), serotype O is predominant, but its viral capsid is more acid sensitive than other serotypes, making it more difficult to produce empty serotype O VLPs in the low pH insect hemolymph. Therefore, a novel chimeric virus-like particle (VLP)-based candidate vaccine for serotype O FMDV was developed and characterized in the present study. The chimeric VLPs were composed of antigenic VP1 from serotype O and segments of viral capsid proteins from serotype Asia1. These VLPs elicited significantly higher FMDV-specific antibody levels in immunized mice than did the inactivated vaccine. Furthermore, the chimeric VLPs protected guinea pigs from FMDV challenge with an efficacy similar to that of the inactivated vaccine. These results suggest that chimeric VLPs have the potential for use in vaccines against serotype O FMDV infection. PMID:26790940

  17. Armed oncolytic virus enhances immune functions of chimeric antigen receptor-modified T cells in solid tumors.

    Science.gov (United States)

    Nishio, Nobuhiro; Diaconu, Iulia; Liu, Hao; Cerullo, Vincenzo; Caruana, Ignazio; Hoyos, Valentina; Bouchier-Hayes, Lisa; Savoldo, Barbara; Dotti, Gianpietro

    2014-09-15

    The clinical efficacy of chimeric antigen receptor (CAR)-redirected T cells remains marginal in solid tumors compared with leukemias. Failures have been attributed to insufficient T-cell migration and to the highly immunosuppressive milieu of solid tumors. To overcome these obstacles, we have combined CAR-T cells with an oncolytic virus armed with the chemokine RANTES and the cytokine IL15, reasoning that the modified oncolytic virus will both have a direct lytic effect on infected malignant cells and facilitate migration and survival of CAR-T cells. Using neuroblastoma as a tumor model, we found that the adenovirus Ad5Δ24 exerted a potent, dose-dependent, cytotoxic effect on tumor cells, whereas CAR-T cells specific for the tumor antigen GD2 (GD2.CAR-T cells) were not damaged. When used in combination, Ad5Δ24 directly accelerated the caspase pathways in tumor cells exposed to CAR-T cells, whereas the intratumoral release of both RANTES and IL15 attracted CAR-T cells and promoted their local survival, respectively, increasing the overall survival of tumor-bearing mice. These preclinical data support the use of this innovative biologic platform of immunotherapy for solid tumors. Cancer Res; 74(18); 5195-205. ©2014 AACR. PMID:25060519

  18. Eliciting neutralizing antibodies against the membrane proximal external region of HIV-1 Env by chimeric live attenuated influenza A virus vaccines.

    Science.gov (United States)

    Zang, Yang; Du, Dongchuan; Li, Na; Su, Weiheng; Liu, Xintao; Zhang, Yan; Nie, Jianhui; Wang, Youchun; Kong, Wei; Jiang, Chunlai

    2015-07-31

    Despite significant efforts directed toward research on HIV-1 vaccines, a truly effective immunogen has not been achieved. However, the broadly neutralizing antibodies (BnAbs) 2F5 and 4E10, targeting the highly conserved membrane proximal external region (MPER) of HIV-1, are two promising tools for vaccine development. Here we engrafted the MPER into the linker domain between the trimeric core structure and the transmembrane domain of influenza A virus HA2 to investigate the potential of such chimeric viruses to elicit HIV-1 neutralizing antibodies. In the context of proliferating attenuated influenza A viruses, these HIV-1 neutralizing antibody epitopes could be continuously expressed and mimicked their native conformation to induce humoral immune responses. While MPER-specific antibodies could be detected in serum of guinea pigs vaccinated with the chimeric viruses, they exhibited only weakly neutralizing activities. These antisera from vaccinated animals neutralized viruses of clades B and BC (tier 1), but not of clades AE (tier 1) and C (tier 2). These results suggest that influenza A virus can be used as a vehicle for displaying MPER and inducing BnAbs, but it provides limited protection against HIV-1 infection. In the future development of HIV-1 vaccines by rational design, a more effective live virus vector or multiple antigens should be chosen to facilitate the process of neutralizing antibody maturation. PMID:26126669

  19. Pathogenesis of Lassa Fever Virus Infection: I. Susceptibility of Mice to Recombinant Lassa Gp/LCMV Chimeric Virus

    OpenAIRE

    Lee, Andrew M.; Cruite, Justin; Welch, Megan J.; Sullivan, Brian; Oldstone, Michael B. A.

    2013-01-01

    Lassa virus (LASV) is a BSL-4 restricted agent. To allow study of infection by LASV under BSL-2 conditions, we generated a recombinant virus in which the LASV glycoprotein (Gp) was placed on the backbone of lymphocytic choriomeningitis virus (LCMV) Cl13 nucleoprotein, Z and polymerase genes (rLCMV Cl13/LASV Gp). The recombinant virus displayed high tropism for dendritic cells following in vitro or in vivo infection. Inoculation of immunocompetent adults resulted in an acute infection, generat...

  20. Pathogenesis of Lassa fever virus infection: I. Susceptibility of mice to recombinant Lassa Gp/LCMV chimeric virus.

    Science.gov (United States)

    Lee, Andrew M; Cruite, Justin; Welch, Megan J; Sullivan, Brian; Oldstone, Michael B A

    2013-08-01

    Lassa virus (LASV) is a BSL-4 restricted agent. To allow study of infection by LASV under BSL-2 conditions, we generated a recombinant virus in which the LASV glycoprotein (Gp) was placed on the backbone of lymphocytic choriomeningitis virus (LCMV) Cl13 nucleoprotein, Z and polymerase genes (rLCMV Cl13/LASV Gp). The recombinant virus displayed high tropism for dendritic cells following in vitro or in vivo infection. Inoculation of immunocompetent adults resulted in an acute infection, generation of virus-specific CD8(+) T cells and clearance of the infection. Inoculation of newborn mice with rLCMV Cl13/LASV Gp resulted in a life-long persistent infection. Interestingly, adoptive transfer of rLCMV Cl13/LASV Gp immune memory cells into such persistently infected mice failed to purge virus but, in contrast, cleared virus from mice persistently infected with wt LCMV Cl13. PMID:23684417

  1. Pathogenesis of Lassa Fever Virus Infection: I. Susceptibility of Mice to Recombinant Lassa Gp/LCMV Chimeric Virus

    Science.gov (United States)

    Lee, Andrew M.; Cruite, Justin; Welch, Megan J.; Sullivan, Brian; Oldstone, Michael B.A.

    2013-01-01

    Lassa virus (LASV) is a BSL-4 restricted agent. To allow study of infection by LASV under BSL-2 conditions, we generated a recombinant virus in which the LASV glycoprotein (Gp) was placed on the backbone of lymphocytic choriomeningitis virus (LCMV) Cl13 nucleoprotein, Z and polymerase genes (rLCMV Cl13/LASV Gp). The recombinant virus displayed high tropism for dendritic cells following in vitro or in vivo infection. Inoculation of immunocompetent adults resulted in an acute infection, generation of virus-specific CD8+ T cells and clearance of the infection. Inoculation of newborn mice with rLCMV Cl13/LASV Gp resulted in a life-long persistent infection. Interestingly, adoptive transfer of rLCMV Cl13/LASV Gp immune memory cells into such persistently infected mice failed to purge virus but, in contrast, cleared virus from mice persistently infected with wt LCMV Cl13. PMID:23684417

  2. The Use of Chimeric Virus-like Particles Harbouring a Segment of Hantavirus Gc Glycoprotein to Generate a Broadly-Reactive Hantavirus-Specific Monoclonal Antibody

    Directory of Open Access Journals (Sweden)

    Aurelija Zvirbliene

    2014-02-01

    Full Text Available Monoclonal antibodies (MAbs against viral glycoproteins have important diagnostic and therapeutic applications. In most cases, the MAbs specific to viral glycoproteins are raised against intact virus particles. The biosynthesis of viral glycoproteins in heterologous expression systems such as bacteria, yeast, insect or mammalian cells is often problematic due to their low expression level, improper folding and limited stability. To generate MAbs against hantavirus glycoprotein Gc, we have used initially a recombinant yeast-expressed full-length Puumala virus (PUUV Gc protein. However, this approach was unsuccessful. As an alternative recombinant antigen, chimeric virus-like particles (VLPs harboring a segment of PUUV Gc glycoprotein were generated in yeast Saccharomyces cerevisiae. A 99 amino acid (aa-long segment of Gc protein was inserted into the major capsid protein VP1 of hamster polyomavirus at previously defined positions: either site #1 (aa 80–89 or site #4 (aa 280–289. The chimeric proteins were found to self-assemble to VLPs as evidenced by electron microscopy. Chimeric VLPs induced an efficient insert-specific antibody response in immunized mice. Monoclonal antibody (clone #10B8 of IgG isotype specific to hantavirus Gc glycoprotein was generated. It recognized recombinant full-length PUUV Gc glycoprotein both in ELISA and Western blot assay and reacted specifically with hantavirus-infected cells in immunofluorescence assay. Epitope mapping studies revealed the N-terminally located epitope highly conserved among different hantavirus strains. In conclusion, our approach to use chimeric VLPs was proven useful for the generation of virus-reactive MAb against hantavirus Gc glycoprotein. The generated broadly-reactive MAb #10B8 might be useful for various diagnostic applications.

  3. Safety and immunogenicity of a live attenuated Japanese encephalitis chimeric virus vaccine (IMOJEV®) in children.

    Science.gov (United States)

    Chokephaibulkit, K; Houillon, G; Feroldi, E; Bouckenooghe, A

    2016-02-01

    JE-CV (IMOJEV®, Sanofi Pasteur, France) is a live attenuated virus vaccine constructed by inserting coding sequences of the prM and E structural proteins of the Japanese encephalitis SA14-14-2 virus into the genome of yellow fever 17D virus. Primary immunization with JE-CV requires a single dose of the vaccine. This article reviews clinical trials of JE-CV in children aged up to 6 years conducted in countries across South-East Asia. Strong and persistent antibody responses were observed after single primary and booster doses, with 97% of children seroprotected up to five years after booster vaccination. Models of long-term antibody persistence predict a median duration of protection of approximately 30 years after a booster dose. The safety and reactogenicity profiles of JE-CV primary and booster doses are comparable to other widely used childhood vaccines. PMID:26588242

  4. A Novel Chimeric Adenoassociated Virus 2/Human Bocavirus 1 Parvovirus Vector Efficiently Transduces Human Airway Epithelia

    OpenAIRE

    Yan, Ziying; Keiser, Nicholas W.; Song, Yi; Deng, Xuefeng; Cheng, Fang; Qiu, Jianming; Engelhardt, John F.

    2013-01-01

    Human bocavirus virus-1 (HBoV1), a newly discovered autonomous parvovirus with a 5,500 nt genome, efficiently infects human-polarized airway epithelia (HAE) from the apical membrane. We hypothesized that the larger genome and high airway tropism of HBoV1 would be ideal for creating a viral vector for lung gene therapy. To this end, we successfully generated recombinant HBoV1 (rHBoV1) from an open reading frames–disrupted rHBoV1 genome that efficiently transduces HAE from the apical surface. W...

  5. Limited Protection from a Pathogenic Chimeric Simian-Human Immunodeficiency Virus Challenge following Immunization with Attenuated Simian Immunodeficiency Virus

    OpenAIRE

    Lewis, Mark G.; Yalley-Ogunro, Jake; Greenhouse, Jack J.; Brennan, Terry P.; Jiang, Jennifer Bo; Thomas C VanCott; Lu, Yichen; Eddy, Gerald A.; Birx, Deborah L.

    1999-01-01

    Two live attenuated single-deletion mutant simian immunodeficiency virus (SIV) constructs, SIV239Δnef and SIVPBj6.6Δnef, were tested for their abilities to stimulate protective immunity in macaques. During the immunization period the animals were examined for specific immune responses and virus growth. Each construct generated high levels of specific immunity in all of the immunized animals. The SIV239Δnef construct was found to grow to high levels in all immunized animals, with some animals ...

  6. Characterization of a chimeric foot-and-mouth disease virus bearing bovine rhinitis B virus leader proteinase

    Science.gov (United States)

    Our recent study has shown that bovine rhinovirus type 2 (BRV2), a new member of the Aphthovirus genus, shares many motifs and sequence similarities with foot-and-mouth disease virus (FMDV). Despite low sequence conservation (36percent amino acid identity) and N- and C-terminus folding differences,...

  7. Chimeric antigen receptor (CAR)-engineered T cells redirected against hepatitis C virus (HCV) E2 glycoprotein

    Science.gov (United States)

    Sautto, Giuseppe A; Wisskirchen, Karin; Clementi, Nicola; Castelli, Matteo; Diotti, Roberta A; Graf, Julia; Clementi, Massimo; Burioni, Roberto; Protzer, Ulrike; Mancini, Nicasio

    2016-01-01

    Objective The recent availability of novel antiviral drugs has raised new hope for a more effective treatment of hepatitis C virus (HCV) infection and its severe sequelae. However, in the case of non-responding or relapsing patients, alternative strategies are needed. To this end we have used chimeric antigen receptors (CARs), a very promising approach recently used in several clinical trials to redirect primary human T cells against different tumours. In particular, we designed the first CARs against HCV targeting the HCV/E2 glycoprotein (HCV/E2). Design Anti-HCV/E2 CARs were composed of single-chain variable fragments (scFvs) obtained from a broadly cross-reactive and cross-neutralising human monoclonal antibody (mAb), e137, fused to the intracellular signalling motif of the costimulatory CD28 molecule and the CD3ζ domain. Activity of CAR-grafted T cells was evaluated in vitro against HCV/E2-transfected cells as well as hepatocytes infected with cell culture-derived HCV (HCVcc). Results In this proof-of-concept study, retrovirus-transduced human T cells expressing anti-HCV/E2 CARs were endowed with specific antigen recognition accompanied by degranulation and secretion of proinflammatory and antiviral cytokines, such as interferon γ, interleukin 2 and tumour necrosis factor α. Moreover, CAR-grafted T cells were capable of lysing target cells of both hepatic and non-hepatic origin expressing on their surface the HCV/E2 glycoproteins of the most clinically relevant genotypes, including 1a, 1b, 2a, 3a, 4 and 5. Finally, and more importantly, they were capable of lysing HCVcc-infected hepatocytes. Conclusions Clearance of HCV-infected cells is a major therapeutic goal in chronic HCV infection, and adoptive transfer of anti-HCV/E2 CARs-grafted T cells represents a promising new therapeutic tool. PMID:25661083

  8. Chimeric Hepatitis B core antigen virus-like particles displaying the envelope domain III of dengue virus type 2

    Directory of Open Access Journals (Sweden)

    Arora Upasana

    2012-07-01

    Full Text Available Abstract Background Dengue is a global public health problem for which no drug or vaccine is available. Currently, there is increasing interest in developing non-replicating dengue vaccines based on a discrete antigenic domain of the major structural protein of dengue viruses (DENVs, known as envelope domain III (EDIII. The use of bio-nanoparticles consisting of recombinant viral structural polypeptides, better known as virus-like particles (VLPs, has emerged as a potential platform technology for vaccine development. This work explores the feasibility of developing nanoparticles based on E. coli-expressed recombinant Hepatitis B virus core antigen (HBcAg designed to display EDIII moiety of DENV on the surface. Findings We designed a synthetic gene construct encoding HBcAg containing an EDIII insert in its c/e1 loop. The fusion antigen HBcAg-EDIII-2 was expressed in E. coli, purified to near homogeneity using Ni+2 affinity chromatography and demonstrated to assemble into discrete 35–40 nm VLPs by electron microscopy. Competitive ELISA analyses showed that the EDIII-2 moieties of the VLPs are accessible to anti-EDIII-2-specific monoclonal and polyclonal antibodies, suggesting that they are surface-displayed. The VLPs were highly immunogenic eliciting high titer anti-EDIII-2 antibodies that were able to recognize, bind and neutralize infectious DENV based on ELISA, immunofluorescence and virus-neutralization assays. Conclusion This work demonstrates that HBcAg-derived nanoparticles can serve as a useful platform for the display of DENV EDIII. The EDIII-displaying nanoparticles may have potential applications in diagnostics/vaccines for dengue.

  9. A Chimeric HIV-1 gp120 Fused with Vaccinia Virus 14K (A27 Protein as an HIV Immunogen.

    Directory of Open Access Journals (Sweden)

    Aneesh Vijayan

    Full Text Available In the HIV vaccine field, there is a need to produce highly immunogenic forms of the Env protein with the capacity to trigger broad B and T-cell responses. Here, we report the generation and characterization of a chimeric HIV-1 gp120 protein (termed gp120-14K by fusing gp120 from clade B with the vaccinia virus (VACV 14K oligomeric protein (derived from A27L gene. Stable CHO cell lines expressing HIV-1 gp120-14K protein were generated and the protein purified was characterized by size exclusion chromatography, electron microscopy and binding to anti-Env antibodies. These approaches indicate that gp120-14K protein is oligomeric and reacts with a wide spectrum of HIV-1 neutralizing antibodies. Furthermore, in human monocyte-derived dendritic cells (moDCs, gp120-14K protein upregulates the levels of several proinflammatory cytokines and chemokines associated with Th1 innate immune responses (IL-1β, IFN-γ, IL-6, IL-8, IL-12, RANTES. Moreover, we showed in a murine model, that a heterologous prime/boost immunization protocol consisting of a DNA prime with a plasmid expressing gp120-14K protein followed by a boost with MVA-B [a recombinant modified vaccinia virus Ankara (MVA expressing HIV-1 gp120, Gag, Pol and Nef antigens from clade B], generates stronger, more polyfunctional, and greater effector memory HIV-1-specific CD4+ and CD8+ T-cell immune responses, than immunization with DNA-gp120/MVA-B. The DNA/MVA protocol was superior to immunization with the combination of protein/MVA and the latter was superior to a prime/boost of MVA/MVA or protein/protein. In addition, these immunization protocols enhanced antibody responses against gp120 of the class IgG2a and IgG3, together favoring a Th1 humoral immune response. These results demonstrate that fusing HIV-1 gp120 with VACV 14K forms an oligomeric protein which is highly antigenic as it activates a Th1 innate immune response in human moDCs, and in vaccinated mice triggers polyfunctional HIV-1

  10. A Chimeric HIV-1 gp120 Fused with Vaccinia Virus 14K (A27) Protein as an HIV Immunogen

    Science.gov (United States)

    Vijayan, Aneesh; García-Arriaza, Juan; C. Raman, Suresh; Conesa, José Javier; Chichón, Francisco Javier; Santiago, César; Sorzano, Carlos Óscar S.; Carrascosa, José L.; Esteban, Mariano

    2015-01-01

    In the HIV vaccine field, there is a need to produce highly immunogenic forms of the Env protein with the capacity to trigger broad B and T-cell responses. Here, we report the generation and characterization of a chimeric HIV-1 gp120 protein (termed gp120-14K) by fusing gp120 from clade B with the vaccinia virus (VACV) 14K oligomeric protein (derived from A27L gene). Stable CHO cell lines expressing HIV-1 gp120-14K protein were generated and the protein purified was characterized by size exclusion chromatography, electron microscopy and binding to anti-Env antibodies. These approaches indicate that gp120-14K protein is oligomeric and reacts with a wide spectrum of HIV-1 neutralizing antibodies. Furthermore, in human monocyte-derived dendritic cells (moDCs), gp120-14K protein upregulates the levels of several proinflammatory cytokines and chemokines associated with Th1 innate immune responses (IL-1β, IFN-γ, IL-6, IL-8, IL-12, RANTES). Moreover, we showed in a murine model, that a heterologous prime/boost immunization protocol consisting of a DNA prime with a plasmid expressing gp120-14K protein followed by a boost with MVA-B [a recombinant modified vaccinia virus Ankara (MVA) expressing HIV-1 gp120, Gag, Pol and Nef antigens from clade B], generates stronger, more polyfunctional, and greater effector memory HIV-1-specific CD4+ and CD8+ T-cell immune responses, than immunization with DNA-gp120/MVA-B. The DNA/MVA protocol was superior to immunization with the combination of protein/MVA and the latter was superior to a prime/boost of MVA/MVA or protein/protein. In addition, these immunization protocols enhanced antibody responses against gp120 of the class IgG2a and IgG3, together favoring a Th1 humoral immune response. These results demonstrate that fusing HIV-1 gp120 with VACV 14K forms an oligomeric protein which is highly antigenic as it activates a Th1 innate immune response in human moDCs, and in vaccinated mice triggers polyfunctional HIV-1-specific adaptive

  11. In vitro and in vivo characterization of chimeric duck Tembusu virus based on Japanese encephalitis live vaccine strain SA14-14-2.

    Science.gov (United States)

    Wang, Hong-Jiang; Liu, Long; Li, Xiao-Feng; Ye, Qing; Deng, Yong-Qiang; Qin, E-De; Qin, Cheng-Feng

    2016-07-01

    Duck Tembusu virus (DTMUV), a newly identified flavivirus, has rapidly spread to China, Malaysia and Thailand. The potential threats to public health have been well-highlighted; however its virulence and pathogenesis remain largely unknown. Here, by using reverse genetics, a recombinant chimeric DTMUV based on Japanese encephalitis live vaccine strain SA14-14-2 was obtained by substituting the corresponding prM and E genes (named ChinDTMUV). In vitro characterization demonstrated that ChinDTMUV replicated efficiently in mammalian cells with small-plaque phenotype in comparison with its parental viruses. Mouse tests showed ChinDTMUV exhibited avirulent phenotype in terms of neuroinvasiveness, while it retained neurovirulence from its parental virus DTMUV. Furthermore, immunization with ChinDTMUV was evidenced to elicit robust IgG and neutralizing antibody responses in mice. Overall, we successfully developed a viable chimeric DTMUV, and these results provide a useful platform for further investigation of the pathogenesis of DTMUV and development of a live attenuated DTMUV vaccine candidate. PMID:27100268

  12. Novel recombinant chimeric virus-like particle is immunogenic and protective against both enterovirus 71 and coxsackievirus A16 in mice

    OpenAIRE

    Hui Zhao; Hao-Yang Li; Jian-Feng Han; Yong-Qiang Deng; Shun-Ya Zhu; Xiao-Feng Li; Hui-Qin Yang; Yue-Xiang Li; Yu Zhang; E-De Qin; Rong Chen; Cheng-Feng Qin

    2015-01-01

    Hand-foot-and-mouth disease (HFMD) has been recognized as an important global public health issue, which is predominantly caused by enterovirus 71 (EV-A71) and coxsackievirus A16 (CVA16). There is no available vaccine against HFMD. An ideal HFMD vaccine should be bivalent against both EV-A71 and CVA16. Here, a novel strategy to produce bivalent HFMD vaccine based on chimeric EV-A71 virus-like particles (ChiEV-A71 VLPs) was proposed and illustrated. The neutralizing epitope SP70 within the cap...

  13. Persistent replication of a hepatitis C virus genotype 1b-based chimeric clone carrying E1, E2 and p6 regions from GB virus B in a New World monkey.

    Science.gov (United States)

    Suzuki, Saori; Mori, Ken-Ichi; Higashino, Atsunori; Iwasaki, Yuki; Yasutomi, Yasuhiro; Maki, Noboru; Akari, Hirofumi

    2016-01-01

    The development of effective hepatitis C virus (HCV) vaccines is essential for the prevention of further HCV dissemination, especially in developing countries. Therefore the aim of this study is to establish a feasible and immunocompetent surrogate animal model of HCV infection that will help in evaluation of the protective efficacy of newly developing HCV vaccine candidates. To circumvent the narrow host range of HCV, an HCV genotype 1b-based chimeric clone carrying E1, E2 and p6 regions from GB virus B (GBV-B), which is closely related to HCV, was generated. The chimera between HCV and GBV-B, named HCV/G, replicated more efficiently as compared with the HCV clone in primary marmoset hepatocytes. Furthermore, it was found that the chimera persistently replicated in a tamarin for more than 2 years after intrahepatic inoculation of the chimeric RNA. Although relatively low (production of the chimeric virus. Our results will help establish a novel non-human primate model for HCV infection on the basis of the HCV/G chimera in the major framework of the HCV genome. PMID:26634303

  14. Chimeric avian paramyxovirus-based vector immunization against highly pathogenic avian influenza followed by conventional Newcastle disease vaccination eliminates lack of protection from virulent ND virus

    Directory of Open Access Journals (Sweden)

    C. Steglich

    2014-01-01

    Full Text Available Recently, we described a chimeric, hemagglutinin of highly pathogenic avian influenza virus (HPAIV H5 expressing Newcastle disease virus (NDV-based vector vaccine (chNDVFHNPMV8H5 in which NDV envelope glycoproteins were replaced by those of avian paramyxovirus-8 (APMV-8. This chimeric vaccine induced solid protection against lethal HPAIV H5N1 even in chickens with maternal antibodies against NDV (MDA+. However, due to the absence of the major NDV immunogens it failed to induce protection against Newcastle disease (ND. Here, we report on protection of MDA+ chickens against HPAI H5N1 and ND, by vaccination with chNDVFHNPMV8H5 either on day 1 or day seven after hatch, and subsequent immunization with live attenuated NDV seven days later. Vaccination was well tolerated and three weeks after immunization, challenge infections with highly pathogenic NDV as well as HPAIV H5N1 were carried out. All animals remained healthy without exhibiting any clinical signs, whereas non-vaccinated animals showed morbidity and mortality. Therefore, vaccination with chNDVFHNPMV8H5 can be followed by NDV vaccination to protect chickens from HPAIV as well as NDV, indicating that the antibody response against chNDVFHNPMV8H5 does not interfere with live ND vaccination.

  15. Novel recombinant chimeric virus-like particle is immunogenic and protective against both enterovirus 71 and coxsackievirus A16 in mice.

    Science.gov (United States)

    Zhao, Hui; Li, Hao-Yang; Han, Jian-Feng; Deng, Yong-Qiang; Zhu, Shun-Ya; Li, Xiao-Feng; Yang, Hui-Qin; Li, Yue-Xiang; Zhang, Yu; Qin, E-De; Chen, Rong; Qin, Cheng-Feng

    2015-01-01

    Hand-foot-and-mouth disease (HFMD) has been recognized as an important global public health issue, which is predominantly caused by enterovirus 71 (EV-A71) and coxsackievirus A16 (CVA16). There is no available vaccine against HFMD. An ideal HFMD vaccine should be bivalent against both EV-A71 and CVA16. Here, a novel strategy to produce bivalent HFMD vaccine based on chimeric EV-A71 virus-like particles (ChiEV-A71 VLPs) was proposed and illustrated. The neutralizing epitope SP70 within the capsid protein VP1 of EV-A71 was replaced with that of CVA16 in ChiEV-A71 VLPs. Structural modeling revealed that the replaced CVA16-SP70 epitope is well exposed on the surface of ChiEV-A71 VLPs. These VLPs produced in Saccharomyces cerevisiae exhibited similarity in both protein composition and morphology as naive EV-A71 VLPs. Immunization with ChiEV-A71 VLPs in mice elicited robust Th1/Th2 dependent immune responses against EV-A71 and CVA16. Furthermore, passive immunization with anti-ChiEV-A71 VLPs sera conferred full protection against lethal challenge of both EV-A71 and CVA16 infection in neonatal mice. These results suggested that this chimeric vaccine, ChiEV-A71 might have the potential to be further developed as a bivalent HFMD vaccine in the near future. Such chimeric enterovirus VLPs provide an alternative platform for bivalent HFMD vaccine development. PMID:25597595

  16. An adenine-to-guanine nucleotide change in the IRES SL-IV domain of picornavirus/hepatitis C chimeric viruses leads to a nonviable phenotype

    International Nuclear Information System (INIS)

    The inability for the internal ribosomal entry site (IRES) of hepatitis C virus (HCV) to be readily studied in the context of viral replication has been circumvented by constructing chimeras such as with poliovirus (PV), in which translation of the genome polyprotein is under control of the HCV IRES. During our attempts to configure the PV/HCV chimera for our drug discovery efforts, we discovered that an adenine- (A) to-guanine (G) change at nt 350 in domain IV of the HCV IRES resulted in a nonviable phenotype. Similarly, a mengovirus (MV)/HCV chimera using the same configuration with a G at nt 350 (G-350) was found to be nonviable. In contrast, a bovine viral diarrhea virus (BVDV)/HCV chimera remained viable with G-350 in the HCV IRES insert. Second-site, resuscitating mutations were identified from the G-350 PV/HCV and MV/HCV viruses after blind passaging. For both viruses, the resuscitating mutations involved destabilization of domain IV in the HCV IRES. The nonviability of G-350 in the picornavirus/HCV chimeric background might be linked to translation efficiency as indicated by analyses with dual reporter and PV/HCV replicon constructs

  17. Chimeric virus-like particles containing a conserved region of the G protein in combination with a single peptide of the M2 protein confer protection against respiratory syncytial virus infection.

    Science.gov (United States)

    Qiao, Lei; Zhang, Yuan; Chai, Feng; Tan, Yiluo; Huo, Chunling; Pan, Zishu

    2016-07-01

    To investigate the feasibility and efficacy of a virus-like particle (VLP) vaccine composed of the conserved antigenic epitopes of respiratory syncytial virus (RSV), the chimeric RSV VLPs HBcΔ-tG and HBcΔ-tG/M282-90 were generated based on the truncated hepatitis B virus core protein (HBcΔ). HBcΔ-tG consisted of HBcΔ, the conserved region (aa 144-204) of the RSV G protein. HBcΔ-tG was combined with a single peptide (aa 82-90) of the M2 protein to generate HBcΔ-tG/M282-90. Immunization of mice with the HBcΔ-tG or HBcΔ-tG/M282-90 VLPs elicited RSV-specific IgG and neutralizing antibody production and conferred protection against RSV infection. Compared with HBcΔ-tG, HBcΔ-tG/M282-90 induced decreased Th2 cytokine production (IL-4 and IL-5), increased Th1 cytokine response (IFN-γ, TNF-α, and IL-2), and increased ratios of IgG2a/IgG1 antibodies, thereby relieving pulmonary pathology upon subsequent RSV infection. Our results demonstrated that chimeric HBcΔ-tG/M282-90 VLPs represented an effective RSV subunit vaccine candidate. PMID:27154395

  18. Deletions within the 3' Non-Translated Region of Alfalfa mosaic virus RNA4 Do Not Affect Replication but Significantly Reduce Long-Distance Movement of Chimeric Tobacco mosaic virus

    Directory of Open Access Journals (Sweden)

    Vidadi Yusibov

    2013-07-01

    Full Text Available Alfalfa mosaic virus (AlMV RNAs 1 and 2 with deletions in their 3' non‑translated regions (NTRs have been previously shown to be encapsidated into virions by coat protein (CP expressed from RNA3, indicating that the 3' NTRs of RNAs 1 and 2 are not required for virion assembly. Here, we constructed various mutants by deleting sequences within the 3' NTR of AlMV subgenomic (sg RNA4 (same as of RNA3 and examined the effect of these deletions on replication and translation of chimeric Tobacco mosaic virus (TMV expressing AlMV sgRNA4 from the TMV CP sg promoter (Av/A4 in tobacco protoplasts and Nicotiana benthamiana plants. While the Av/A4 mutants were as competent as the wild-type Av/A4 in RNA replication in protoplasts, their encapsidation, long-distance movement and virus accumulation varied significantly in N. benthamiana. These data suggest that the 3' NTR of AlMV sgRNA4 contains potential elements necessary for virus encapsidation.

  19. Deletions within the 3' non-translated region of Alfalfa mosaic virus RNA4 do not affect replication but significantly reduce long-distance movement of chimeric Tobacco mosaic virus.

    Science.gov (United States)

    Roy, Gourgopal; Fedorkin, Oleg; Fujiki, Masaaki; Skarjinskaia, Marina; Knapp, Elisabeth; Rabindran, Shailaja; Yusibov, Vidadi

    2013-07-01

    Alfalfa mosaic virus (AlMV) RNAs 1 and 2 with deletions in their 3' non‑translated regions (NTRs) have been previously shown to be encapsidated into virions by coat protein (CP) expressed from RNA3, indicating that the 3' NTRs of RNAs 1 and 2 are not required for virion assembly. Here, we constructed various mutants by deleting sequences within the 3' NTR of AlMV subgenomic (sg) RNA4 (same as of RNA3) and examined the effect of these deletions on replication and translation of chimeric Tobacco mosaic virus (TMV) expressing AlMV sgRNA4 from the TMV CP sg promoter (Av/A4) in tobacco protoplasts and Nicotiana benthamiana plants. While the Av/A4 mutants were as competent as the wild-type Av/A4 in RNA replication in protoplasts, their encapsidation, long-distance movement and virus accumulation varied significantly in N. benthamiana. These data suggest that the 3' NTR of AlMV sgRNA4 contains potential elements necessary for virus encapsidation. PMID:23867804

  20. 猪繁殖与呼吸综合征病毒强弱毒株嵌合感染性克隆的构建及鉴定%The Construction of Chimeric Clone of Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus and Attenuated PRRSV Strain and Identification of Chimeric Viruses Rescued

    Institute of Scientific and Technical Information of China (English)

    吕健; 韦祖樟; 高飞; 郑海红; 童光志; 袁世山

    2012-01-01

    Porcine reproductive and respiratory syndrome virus (PRRSV), the causative agent of the ongoing "porcine high fever syndrome" in China, is capable of genetic and antigenic mutations at high frequency. How to design vaccine rationally to keep up with the ever-changing prevalent PRRSV variant is of great interest. In this study, based on an infectious cDNA clone of an attenuated Typell PRRSV strain pAPRRS and the highly pathogenic PRRSV cDNA clone pJX143, we replaced the coding sequence of pAPRRS nsp2 with those of the HP PRRSV to develop a series of chimeric clones. Upon transfection of chimeric clones into MA104 cells, typical PRRSV cyto-pathic effects were observed. This study provided a valuable tool to develop the chimeric PRRSV as vaccine candidate offering cross-protection to HP PRRSV strains. Furthermore, the infectious chimeric cDNA clone provides a powerful tool to molecular dissection of the mechanism of patho-genesis of the increasing-virulence of the on-going prevalent PRRSV in China.%查明猪繁殖与呼吸综合征病毒(PRRSV)致病性大幅增高的机制,进而研制用于防治流行PRRSV变异株的高效疫苗无疑是兽医工作者的当务之急.在弱毒株APRRS的全长感染性克隆pAPRRS以及我室构建的高致病性HP PRRSV感染性克隆pJX143的基础上,构建了nsp2替换的强弱毒PRRSV嵌合感染性克隆.将构建的嵌合克隆转染MA104,4d后观察到典型的CPE.通过RT-PCR和免疫荧光证明获得了一系列强弱毒株之间的嵌合病毒.这些嵌合病毒的构建成功和相应反向遗传操作平台的建立及应用,为研发预防HP PRRSV的高效嵌合疫苗奠定了基础.该类嵌合感染性cDNA克隆也为解析目前流行的HP PRRSV毒力因子和高致病力机制奠定了基础.

  1. Characterization of Hepatitis C Virus Recombinants with Chimeric E1/E2 Envelope Proteins and Identification of Single Amino Acids in the E2 Stem Region Important for Entry

    OpenAIRE

    Carlsen, Thomas H. R.; Scheel, Troels K. H.; Ramirez, Santseharay; Foung, Steven K. H.; Bukh, Jens

    2013-01-01

    The hepatitis C virus (HCV) envelope proteins E1 and E2 play a key role in host cell entry and represent important targets for vaccine and drug development. Here, we characterized HCV recombinants with chimeric E1/E2 complexes in vitro. Using genotype 1a/2a JFH1-based recombinants expressing 1a core-NS2, we exchanged E2 with functional isolate sequences of genotypes 1a (alternative isolate), 1b, and 2a. While the 1a-E2 exchange did not impact virus viability, the 2a-E2 recombinant was nonviab...

  2. Tissue-Specific Replicating Capacity of a Chimeric Poliovirus That Carries the Internal Ribosome Entry Site of Hepatitis C Virus in a New Mouse Model Transgenic for the Human Poliovirus Receptor

    OpenAIRE

    Yanagiya, Akiko; Ohka, Seii; Hashida, Noriyasu; Okamura, Masahito; Taya, Choji; Kamoshita, Nobuhiko; Iwasaki, Kuniko; Sasaki, Yukari; Yonekawa, Hiromichi; Nomoto, Akio

    2003-01-01

    Nucleotides (nt) 108 to 742 of an infectious cDNA clone of poliovirus (PV) Mahoney strain, including the corresponding region of the internal ribosome entry site (IRES), was replaced by nt 28 to 710 of hepatitis C virus (HCV) cDNA corresponding to the whole HCV IRES. A chimeric PV (2A-369) was generated by transfecting mammalian cells with an RNA transcribed in vitro from the cDNA. To examine replicating capacity of virus 2A-369 in the brain and liver of a mouse model for poliomyelitis, a new...

  3. Design and construction of chimeric virus-like particles of Dengue and Japanese encephalitis virus%登革-日本脑炎嵌合病毒样颗粒的设计与构建

    Institute of Scientific and Technical Information of China (English)

    胡珍; 尚伟龙; 张俊磊; 朱军民; 杨杰; 刘佳; 方昕; 袁文常; 程航

    2011-01-01

    Objective To construct the chimeric virus-like particles ( VLPs) of Dengue and Japanese encephalitis viruses. Methods An expression vector was constructed by the formation of a Dengue virus (DV) and the gene of neutralizing epitopes of Japanese encephalitis envelope E. The constructed vector was transfected in BHK-21 cells and selected by G418 sulfate. The supernatant of selected cell culture was collected for chimeric VLPs purification. The recombinant VLPs were characterized by western blot and transmission electron microscope (TEM). Results The recombined expression plasmid of pCI-SMEJ-14 # carrying the fusion gene of interest was constructed and confirmed by restriction enzymes analysis and DNA sequencing. With successful BHK-21 cells transfection and 0. 6 mg/mlof G418 selection, 4 clones secreted the fusion proteins of Dengue and Japanese encephalitis virus as desired. Diameters of 30-100 nm VLPs could be assembled by the expressed proteins under TEM. Conclusion The chimeric protein of VLPs may be valuable in preventing Dengue and Japanese encephalitis virus infection.%目的 设计构建登革-日本脑炎嵌合蛋白表达载体,制备嵌合病毒样颗粒.方法 根据登革病毒样颗粒的形成机制及日本脑炎病毒中和性抗原表位的分布,设计并构建登革-日本脑炎嵌合蛋白表达载体,转染BHK-21细胞,筛选能表达目标蛋白的G418抗性克隆,收集细胞培养上清,纯化病毒样颗粒,用Western-blot和电镜检测病毒样颗粒的形成.结果用RT-PCR扩增、酶切和连接等分子生物学方法成功构建了序列及阅读框均正确的重组表达质粒pCI-SMEJ-14#;将该质粒转染BHK-21细胞,经0.6 g/LG418筛选获得4个能表达目标嵌合蛋白的克隆,从培养的细胞上清中能纯化出直径30~100 nm的病毒样颗粒.结论 所设计的登革-日本脑炎病毒嵌合蛋白能在BHK-21细胞中产生病毒样颗粒,为制备新一代登革-日本脑炎嵌合型疫苗奠定了良好基础.

  4. An E2-Substituted Chimeric Pestivirus With DIVA Vaccine Properties

    DEFF Research Database (Denmark)

    Rasmussen, Thomas Bruun; Uttenthal, Åse; Nielsen, Jens;

    An advantage of the use of chimeric pestiviruses as modified live vaccines against classical swine fever (CSF) resides in their capacity to be manipulated to achieve the characteristics desired for safe and efficacious DIVA vaccines. We have recently generated a new chimeric virus, Riems26_E2gif...

  5. Co-delivery of GPI-anchored CCL28 and influenza HA in chimeric virus-like particles induces cross-protective immunity against H3N2 viruses.

    Science.gov (United States)

    Mohan, Teena; Kim, Jongrok; Berman, Zachary; Wang, Shelly; Compans, Richard W; Wang, Bao-Zhong

    2016-07-10

    Influenza infection typically initiates at respiratory mucosal surfaces. Induction of immune responses at the sites where pathogens initiate replication is crucial for the prevention of infection. We studied the adjuvanticity of GPI-anchored CCL28 co-incorporated with influenza HA-antigens in chimeric virus-like particles (cVLPs), in boosting strong protective immune responses through an intranasal (i.n.) route in mice. We compared the immune responses to that from influenza VLPs without CCL28, or physically mixed with soluble CCL28 at systemic and various mucosal compartments. The cVLPs containing GPI-CCL28 showed in-vitro chemotactic activity towards spleen and lung cells expressing CCR3/CCR10 chemokine receptors. The cVLPs induced antigen specific endpoint titers and avidity indices of IgG in sera and IgA in tracheal, lung, and intestinal secretions, significantly higher (4-6 fold) than other formulations. Significantly higher (3-5 fold) hemagglutination inhibition titers and high serum neutralization against H3N2 viruses were also detected with CCL28-containing VLPs compared to other groups. The CCL28-containing VLPs showed complete and 80% protection, when vaccinated animals were challenged with A/Aichi/2/1968/H3N2 (homologous) and A/Philippines/2/1982/H3N2 (heterologous) viruses, respectively. Thus, GPI-anchored CCL28 in influenza VLPs act as a strong immunostimulator at both systemic and mucosal sites, boosting significant cross-protection in animals against heterologous viruses across a large distance. PMID:27178810

  6. Hepatitis C virus dynamics and cellular gene expression in uPA-SCID chimeric mice with humanized livers during intravenous silibinin monotherapy.

    Science.gov (United States)

    DebRoy, S; Hiraga, N; Imamura, M; Hayes, C N; Akamatsu, S; Canini, L; Perelson, A S; Pohl, R T; Persiani, S; Uprichard, S L; Tateno, C; Dahari, H; Chayama, K

    2016-09-01

    Legalon SIL (SIL) is a chemically hydrophilized version of silibinin, an extract of milk thistle (Silybum marianum) seeds that has exhibited hepatoprotective and antiviral effectiveness against hepatitis C virus (HCV) in patients leading to viral clearance in combination with ribavirin. To elucidate the incompletely understood mode of action of SIL against HCV, mathematical modelling of HCV kinetics and human hepatocyte gene expression studies were performed in uPA-SCID-chimeric mice with humanized livers. Chronically HCV-infected mice (n = 15) were treated for 14 days with daily intravenous SIL at 469, 265 or 61.5 mg/kg. Serum HCV and human albumin (hAlb) were measured frequently, and liver HCV RNA was analysed at days 3 and 14. Microarray analysis of human hepatocyte gene expression was performed at days 0, 3 and 14 of treatment. While hAlb remained constant, a biphasic viral decline in serum was observed consisting of a rapid 1st phase followed by a second slower phase (or plateau with the two lower SIL dosings). SIL effectiveness in blocking viral production was similar among dosing groups (median ε = 77%). However, the rate of HCV-infected hepatocyte decline, δ, was dose-dependent. Intracellular HCV RNA levels correlated (r = 0.66, P = 0.01) with serum HCV RNA. Pathway analysis revealed increased anti-inflammatory and antiproliferative gene expression in human hepatocytes in SIL-treated mice. The results suggest that SIL could lead to a continuous second-phase viral decline, that is potentially viral clearance, in the absence of adaptive immune response along with increased anti-inflammatory and antiproliferative gene expression in human hepatocytes. PMID:27272497

  7. Mutational analysis of the hepatitis C virus E1 glycoprotein in retroviral pseudoparticles and cell-culture-derived H77/JFH1 chimeric infectious virus particles

    DEFF Research Database (Denmark)

    Russell, R S; Kawaguchi, K; Meunier, J-C; Takikawa, S; Faulk, K; Bukh, J; Purcell, R H; Emerson, S U

    2009-01-01

    Cell entry by enveloped viruses is mediated by viral glycoproteins, and generally involves a short hydrophobic peptide (fusion peptide) that inserts into the cellular membrane. An internal hydrophobic domain within E1 (aa262-290) of hepatitis C virus (HCV) may function as a fusion peptide....... Retrovirus-based HCV-pseudotyped viruses (HCVpp; genotype 1a) containing Ala or Pro substitutions at conserved amino acid positions within this putative fusion peptide were generated. Mutation of conserved residues significantly reduced efficiency of HCVpp entry into Huh-7 cells. The majority of amino acid....... However, the S283P mutation had a different effect in the two systems as it did not increase production of infectious HCVcc. This comprehensive mutational analysis of the putative HCV fusion peptide provides insight into the role of E1 in its interaction with E2 and in HCV entry....

  8. An HPV 16 L1-based chimeric human papilloma virus-like particles containing a string of epitopes produced in plants is able to elicit humoral and cytotoxic T-cell activity in mice

    Directory of Open Access Journals (Sweden)

    Weiss-Steider Benny

    2009-01-01

    Full Text Available Abstract Background Even though two prophylactic vaccines against HPV are currently licensed, infections by the virus continue to be a major health problem mainly in developing countries. The cost of the vaccines limits wide-scale application in poor countries. A promising strategy for producing affordable and efficient vaccines involves the expression of recombinant immunogens in plants. Several HPV genes have been expressed in plants, including L1, which can self-assemble into virus-like particles. A plant-based, dual prophylactic/therapeutic vaccine remains an attractive possibility. Results We sought to express in tomato plants chimeric HPV 16 VLPs containing L1 fused to a string of epitopes from HPV 16 E6 and E7 proteins. The L1 employed had been modified to eliminate a strong inhibitory region at the 5' end of the molecule to increase expression levels. Several tomato lines were obtained expressing either L1 alone or L1-E6/E7 from 0.05% to 0.1% of total soluble protein. Stable integration of the transgenes was verified by Southern blot. Northern and western blot revealed successful expression of the transgenes at the mRNA and protein level. The chimeric VLPs were able to assemble adequately in tomato cells. Intraperitoneal administration in mice was able to elicit both neutralizing antibodies against the viral particle and cytotoxic T-lymphocytes activity against the epitopes. Conclusion In this work, we report for the first time the expression in plants of a chimeric particle containing the HPV 16 L1 sequence and a string of T-cell epitopes from HPV 16 E6 and E7 fused to the C-terminus. The particles were able to induce a significant antibody and cytotoxic T-lymphocytes response. Experiments in vivo are in progress to determine whether the chimeric particles are able to induce regression of disease and resolution of viral infection in mice. Chimeric particles of the type described in this work may potentially be the basis for developing

  9. Crystal Structures of Yeast-Produced Enterovirus 71 and Enterovirus 71/Coxsackievirus A16 Chimeric Virus-Like Particles Provide the Structural Basis for Novel Vaccine Design against Hand-Foot-and-Mouth Disease

    Science.gov (United States)

    Lyu, Ke; He, Ya-Ling; Li, Hao-Yang

    2015-01-01

    ABSTRACT Human enterovirus 71 (EV71) and coxsackievirus A16 (CVA16) are the two major causative agents for hand-foot-and-mouth disease (HFMD). Previously, we demonstrated that a virus-like particle (VLP) for EV71 produced from Saccharomyces cerevisiae is a potential vaccine candidate against EV71 infection, and an EV71/CVA16 chimeric VLP can elicit protective immune responses against both virus infections. Here, we presented the crystal structures of both VLPs, showing that both the linear and conformational neutralization epitopes identified in EV71 are mostly preserved on both VLPs. The replacement of only 4 residues in the VP1 GH loop converted strongly negatively charged surface patches formed by portions of the SP70 epitope in EV71 VLP into a relatively neutral surface in the chimeric VLP, which likely accounted for the additional neutralization capability of the chimeric VLP against CVA16 infection. Such local variations in the amino acid sequences and the surface charge potential are also present in different types of polioviruses. In comparison to EV71 VLP, the chimeric VLP exhibits structural changes at the local site of amino acid replacement and the surface loops of all capsid proteins. This is consistent with the observation that the VP1 GH loop located near the pseudo-3-fold junction is involved in extensive interactions with other capsid regions. Furthermore, portions of VP0 and VP1 in EV71 VLP are at least transiently exposed, revealing the structural flexibility of the VLP. Together, our structural analysis provided insights into the structural basis of enterovirus neutralization and novel vaccine design against HFMD and other enterovirus-associated diseases. IMPORTANCE Our previous studies demonstrated that the enterovirus 71 (EV71) virus-like particle (VLP) produced from yeast is a vaccine candidate against EV71 infection and that a chimeric EV71/coxsackievirus A16 (CVA16) VLP with the replacement of 4 amino acids in the VP1 GH loop can confer

  10. A chimeric 18L1-45RG1 virus-like particle vaccine cross-protects against oncogenic alpha-7 human papillomavirus types.

    Directory of Open Access Journals (Sweden)

    Bettina Huber

    Full Text Available Persistent infection with oncogenic human papillomaviruses (HPV types causes all cervical and a subset of other anogenital and oropharyngeal carcinomas. Four high-risk (hr mucosal types HPV16, 18, 45, or 59 cause almost all cervical adenocarcinomas (AC, a subset of cervical cancer (CxC. Although the incidence of cervical squamous cell carcinoma (SCC has dramatically decreased following introduction of Papanicolaou (PAP screening, the proportion of AC has relatively increased. Cervical SCC arise mainly from the ectocervix, whereas AC originate primarily from the endocervical canal, which is less accessible to obtain viable PAP smears. Licensed (bivalent and quadrivalent HPV vaccines comprise virus-like particles (VLP of the most important hr HPV16 and 18, self-assembled from the major capsid protein L1. Due to mainly type-restricted efficacy, both vaccines do not target 13 additional hr mucosal types causing 30% of CxC. The papillomavirus genus alpha species 7 (α7 includes a group of hr types of which HPV18, 45, 59 are proportionally overrepresented in cervical AC and only partially (HPV18 targeted by current vaccines. To target these types, we generated a chimeric vaccine antigen that consists of a cross-neutralizing epitope (homologue of HPV16 RG1 of the L2 minor capsid protein of HPV45 genetically inserted into a surface loop of HPV18 L1 VLP (18L1-45RG1. Vaccination of NZW rabbits with 18L1-45RG1 VLP plus alum-MPL adjuvant induced high-titer neutralizing antibodies against homologous HPV18, that cross-neutralized non-cognate hr α7 types HPV39, 45, 68, but not HPV59, and low risk HPV70 in vitro, and induced a robust L1-specific cellular immune response. Passive immunization protected mice against experimental vaginal challenge with pseudovirions of HPV18, 39, 45 and 68, but not HPV59 or the distantly related α9 type HPV16. 18L1-45RG1 VLP might be combined with our previously described 16L1-16RG1 VLP to develop a second generation bivalent

  11. Neurocognitive outcome of children exposed to perinatal mother-to-child Chikungunya virus infection: the CHIMERE cohort study on Reunion Island.

    Directory of Open Access Journals (Sweden)

    Patrick Gérardin

    2014-07-01

    Full Text Available Little is known about the neurocognitive outcome in children exposed to perinatal mother-to-child Chikungunya virus (p-CHIKV infection.The CHIMERE ambispective cohort study compared the neurocognitive function of 33 p-CHIKV-infected children (all but one enrolled retrospectively at around two years of age with 135 uninfected peers (all enrolled prospectively. Psychomotor development was assessed using the revised Brunet-Lezine scale, examiners blinded to infectious status. Development quotients (DQ with subscores covering movement/posture, coordination, language, sociability skills were calculated. Predictors of global neurodevelopmental delay (GND, DQ ≤ 85, were investigated using multivariate Poisson regression modeling. Neuroradiologic follow-up using magnetic resonance imaging (MRI scans was proposed for most of the children with severe forms.The mean DQ score was 86.3 (95%CI: 81.0-91.5 in infected children compared to 100.2 (95%CI: 98.0-102.5 in uninfected peers (P<0.001. Fifty-one percent (n = 17 of infected children had a GND compared to 15% (n = 21 of uninfected children (P<0.001. Specific neurocognitive delays in p-CHIKV-infected children were as follows: coordination and language (57%, sociability (36%, movement/posture (27%. After adjustment for maternal social situation, small for gestational age, and head circumference, p-CHIKV infection was found associated with GND (incidence rate ratio: 2.79, 95%CI: 1.45-5.34. Further adjustments on gestational age or breastfeeding did not change the independent effect of CHIKV infection on neurocognitive outcome. The mean DQ of p-CHIKV-infected children was lower in severe encephalopathic children than in non-severe children (77.6 versus 91.2, P<0.001. Of the 12 cases of CHIKV neonatal encephalopathy, five developed a microcephaly (head circumference <-2 standard deviations and four matched the definition of cerebral palsy. MRI scans showed severe restrictions of white matter areas

  12. Identification of full-length transmitted/founder viruses and their progeny in primary HIV-1 infection

    Energy Technology Data Exchange (ETDEWEB)

    Korber, Bette [Los Alamos National Laboratory; Hraber, Peter [Los Alamos National Laboratory; Giorgi, Elena [Los Alamos National Laboratory; Bhattacharya, T [Los Alamos National Laboratory

    2009-01-01

    Identification of transmitted/founder virus genomes and their progeny by is a novel strategy for probing the molecular basis of HIV-1 transmission and for evaluating the genetic imprint of viral and host factors that act to constrain or facilitate virus replication. Here, we show in a cohort of twelve acutely infected subjects (9 clade B; 3 clade C), that complete genomic sequences of transmitted/founder viruses could be inferred using single genome amplification of plasma viral RNA, direct amplicon sequencing, and a model of random virus evolution. This allowed for the precise identification, chemical synthesis, molecular cloning, and biological analysis of those viruses actually responsible for productive clinical infection and for a comprehensive mapping of sequential viral genomes and proteomes for mutations that are necessary or incidental to the establishment of HIV-1 persistence. Transmitted/founder viruses were CD4 and CCR5 tropic, replicated preferentially in activated primary T-Iymphocytes but not monocyte-derived macrophages, and were effectively shielded from most heterologous or broadly neutralizing antibodies. By 3 months of infection, the evolving viral quasispecies in three subjects showed mutational fixation at only 2-5 discreet genomic loci. By 6-12 months, mutational fixation was evident at 18-27 genomic loci. Some, but not all, of these mutations were attributable to virus escape from cytotoxic Tlymphocytes or neutralizing antibodies, suggesting that other viral or host factors may influence early HIV -1 fitness.

  13. CD4+ and CD8+ T cells can act separately in tumour rejection after immunization with murine pneumotropic virus chimeric Her2/neu virus-like particles.

    Directory of Open Access Journals (Sweden)

    Kalle Andreasson

    Full Text Available BACKGROUND: Immunization with murine pneumotropic virus virus-like particles carrying Her2/neu (Her2MPtVLPs prevents tumour outgrowth in mice when given prophylactically, and therapeutically if combined with the adjuvant CpG. We investigated which components of the immune system are involved in tumour rejection, and whether long-term immunological memory can be obtained. METHODOLOGY AND RESULTS: During the effector phase in BALB/c mice, only depletion of CD4+ and CD8+ in combination, with or without NK cells, completely abrogated tumour protection. Depletion of single CD4+, CD8+ or NK cell populations only had minor effects. During the immunization/induction phase, combined depletion of CD4+ and CD8+ cells abolished protection, while depletion of each individual subset had no or negligible effect. When tumour rejection was studied in knock-out mice with a C57Bl/6 background, protection was lost in CD4-/-CD8-/- and CD4-/-, but not in CD8-/- mice. In contrast, when normal C57Bl/6 mice were depleted of different cell types, protection was lost irrespective of whether only CD4+, only CD8+, or CD4+ and CD8+ cells in combination were eradicated. No anti-Her2/neu antibodies were detected but a Her2/neu-specific IFNgamma response was seen. Studies of long-term memory showed that BALB/c mice could be protected against tumour development when immunized together with CpG as long as ten weeks before challenge. CONCLUSION: Her2MPtVLP immunization is efficient in stimulating several compartments of the immune system, and induces an efficient immune response including long-term memory. In addition, when depleting mice of isolated cellular compartments, tumour protection is not as efficiently abolished as when depleting several immune compartments together.

  14. DIVA vaccine properties of the live chimeric pestivirus strain CP7_E2gif

    DEFF Research Database (Denmark)

    von Rosen, Tanya; Rangelova, Desislava Yordanova; Nielsen, Jens;

    2014-01-01

    Live modified vaccines to protect against classical swine fever virus (CSFV), based on chimeric pestiviruses, have been developed to enable serological Differentiation of Infected from Vaccinated Animals (DIVA). In this context, the chimeric virus CP7_E2gif vaccine candidate is unique as it does...

  15. The neurovirulence and neuroinvasiveness of chimeric tick-borne encephalitis/dengue virus can be attenuated by introducing defined mutations into the envelope and NS5 protein genes and the 3' non-coding region of the genome

    International Nuclear Information System (INIS)

    Tick-borne encephalitis (TBE) is a severe disease affecting thousands of people throughout Eurasia. Despite the use of formalin-inactivated vaccines in endemic areas, an increasing incidence of TBE emphasizes the need for an alternative vaccine that will induce a more durable immunity against TBE virus (TBEV). The chimeric attenuated virus vaccine candidate containing the structural protein genes of TBEV on a dengue virus genetic background (TBEV/DEN4) retains a high level of neurovirulence in both mice and monkeys. Therefore, attenuating mutations were introduced into the envelope (E315) and NS5 (NS5654,655) proteins, and into the 3' non-coding region (Δ30) of TBEV/DEN4. The variant that contained all three mutations (vΔ30/E315/NS5654,655) was significantly attenuated for neuroinvasiveness and neurovirulence and displayed a reduced level of replication and virus-induced histopathology in the brains of mice. The high level of safety in the central nervous system indicates that vΔ30/E315/NS5654,655 should be further evaluated as a TBEV vaccine.

  16. Electroejaculation of chimeric rats

    OpenAIRE

    McCoy, Marina R.; Montonye, Daniel; Bryda, Elizabeth C.

    2013-01-01

    With the advent of genetic engineering of rodents came the need to assess fertility and germline competency, especially in chimeric rodents generated using embryonic stem cells. Traditional methods rely on natural mating and progeny testing, which is time- and cost-intensive. Electroejaculation is a faster method of collecting sperm for genetic analysis and offers the additional benefit of using fewer animals. This column describes a refined electroejaculation technique for chimeric rats usin...

  17. Virulence, immunogenicity and vaccine properties of a novel chimeric pestivirus

    DEFF Research Database (Denmark)

    Rasmussen, Thomas Bruun; Uttenthal, Åse; Reimann, Ilona;

    2007-01-01

    avirulent and neither chimeric virus nor viral RNA was detected in serum after vaccination. The safety of the vaccine was tested by horizontal transmission to sentinel pigs, which remained uninfected. The vaccine efficacy was examined by challenge infection with classical swine fever virus (CSFV) Eystrup...

  18. Characterization of hepatitis C virus recombinants with chimeric E1/E2 envelope proteins and identification of single amino acids in the E2 stem region important for entry

    DEFF Research Database (Denmark)

    Carlsen, Thomas H R; Scheel, Troels K H; Ramirez, Santseharay;

    2013-01-01

    . For recovered 1b-E2 recombinants, single E2 stem region amino acid changes were identified at residues 706, 707, and 710. In reverse genetic studies, these mutations increased infectivity titers by ~100-fold, apparently without influencing particle stability or cell binding although introducing slight...... decrease in particle density. In addition, the 1b-E2 exchange led to a decrease in secreted core protein of 25 to 50%, which was further reduced by the E2 stem region mutations. These findings indicated that compensatory mutations permitted robust infectious virus production, without increasing assembly....../release. Studies of E1/E2 heterodimerization showed no differences in intracellular E1/E2 interaction for chimeric constructs with or without E2 stem region mutations. Interestingly, the E2 stem region mutations allowed efficient entry, which was verified in 1a-E1/1b-E2 HCV pseudoparticle assays. A CD81 inhibition...

  19. Electroejaculation of chimeric rats.

    Science.gov (United States)

    McCoy, Marina R; Montonye, Daniel; Bryda, Elizabeth C

    2013-06-01

    With the advent of genetic engineering of rodents came the need to assess fertility and germline competency, especially in chimeric rodents generated using embryonic stem cells. Traditional methods rely on natural mating and progeny testing, which is time- and cost-intensive. Electroejaculation is a faster method of collecting sperm for genetic analysis and offers the additional benefit of using fewer animals. This column describes a refined electroejaculation technique for chimeric rats using light gas anesthesia and a custom-made platform for sperm collection. PMID:23689457

  20. Chimeric Pestivirus Experimental Vaccines.

    Science.gov (United States)

    Reimann, Ilona; Blome, Sandra; Beer, Martin

    2016-01-01

    Chimeric pestiviruses have shown great potential as marker vaccine candidates against pestiviral infections. Exemplarily, we describe here the construction and testing of the most promising classical swine fever vaccine candidate "CP7_E2alf" in detail. The description is focused on classical cloning technologies in combination with reverse genetics. PMID:26458840

  1. Impaired virus control and severe CD8+ T-cell-mediated immunopathology in chimeric mice deficient in gamma interferon receptor expression on both parenchymal and hematopoietic cells

    DEFF Research Database (Denmark)

    Henrichsen, Pernille; Bartholdy, Christina; Christensen, Jan Pravsgaard;

    2005-01-01

    Bone marrow chimeras were used to determine the cellular target(s) for the antiviral activity of gamma interferon (IFN-gamma). By transfusing such mice with high numbers of naive virus-specific CD8(+) T cells, a system was created in which the majority of virus-specific CD8(+) T cells would be...

  2. Challenge pools of hepatitis C virus genotypes 1-6 prototype strains: replication fitness and pathogenicity in chimpanzees and human liver-chimeric mouse models

    DEFF Research Database (Denmark)

    Bukh, Jens; Meuleman, Philip; Tellier, Raymond;

    2010-01-01

    Chimpanzees represent the only animal model for studies of the natural history of hepatitis C virus (HCV). To generate virus stocks of important HCV variants, we infected chimpanzees with HCV strains of genotypes 1-6 and determined the infectivity titer of acute-phase plasma pools in additional...... resource for studies of HCV molecular virology and for studies of pathogenesis, protective immunity, and vaccine efficacy in vivo....

  3. Chimeric polioviruses that include sequences derived from two independent antigenic sites of foot-and-mouth disease virus (FMDV) induce neutralizing antibodies against FMDV in guinea pigs.

    OpenAIRE

    Kitson, J D; Burke, K L; Pullen, L A; Belsham, G J; Almond, J W

    1991-01-01

    Five poliovirus recombinants containing sequences corresponding to foot-and-mouth disease virus (FMDV) antigenic sites were constructed. Viable virus was recovered from four of these plasmids, in which the VP1 beta B-beta C loop (antigenic site 1) of poliovirus type 1 Sabin had been replaced with sequences derived from the VP1 beta G-beta H loop (antigenic site 1) of FMDV O1 Kaufbeuren (O1K), chimera O1.1 (residues 141 to 154), chimera O1.2 (residues 147 to 156), and chimera O1.3 (residues 14...

  4. Antiretroviral therapy and drug resistance in human immunodeficiency virus type 2 infection.

    Science.gov (United States)

    Menéndez-Arias, Luis; Alvarez, Mar

    2014-02-01

    One to two million people worldwide are infected with the human immunodeficiency virus type 2 (HIV-2), with highest prevalences in West African countries, but also present in Western Europe, Asia and North America. Compared to HIV-1, HIV-2 infection undergoes a longer asymptomatic phase and progresses to AIDS more slowly. In addition, HIV-2 shows lower transmission rates, probably due to its lower viremia in infected individuals. There is limited experience in the treatment of HIV-2 infection and several antiretroviral drugs used to fight HIV-1 are not effective against HIV-2. Effective drugs against HIV-2 include nucleoside analogue reverse transcriptase (RT) inhibitors (e.g. zidovudine, tenofovir, lamivudine, emtricitabine, abacavir, stavudine and didanosine), protease inhibitors (saquinavir, lopinavir and darunavir), and integrase inhibitors (raltegravir, elvitegravir and dolutegravir). Maraviroc, a CCR5 antagonist blocking coreceptor binding during HIV entry, is active in vitro against CCR5-tropic HIV-2 but more studies are needed to validate its use in therapeutic treatments against HIV-2 infection. HIV-2 strains are naturally resistant to a few antiretroviral drugs developed to suppress HIV-1 propagation such as nonnucleoside RT inhibitors, several protease inhibitors and the fusion inhibitor enfuvirtide. Resistance selection in HIV-2 appears to be faster than in HIV-1. In this scenario, the development of novel drugs specific for HIV-2 is an important priority. In this review, we discuss current anti-HIV-2 therapies and mutational pathways leading to drug resistance. PMID:24345729

  5. THE PERSISTENCE OF CHICKEN HERPES AND RETRO VIRAL CHIMERIC MOLECULES UPON IN VIVO PASSAGE

    Science.gov (United States)

    Marek's disease virus, a herpes virus, and avian leucosis virus subgroup J, a retrovirus were used for experimental co-infection of chicks. Two consecutive trials were performed in attempt to evaluate the formation and persistence of chimeric molecules that would indicate retro-viral integration int...

  6. The Use of Chimeric Virus-like Particles Harbouring a Segment of Hantavirus Gc Glycoprotein to Generate a Broadly-Reactive Hantavirus-Specific Monoclonal Antibody

    OpenAIRE

    Aurelija Zvirbliene; Indre Kucinskaite-Kodze; Ausra Razanskiene; Rasa Petraityte-Burneikiene; Boris Klempa; Ulrich, Rainer G.; Alma Gedvilaite

    2014-01-01

    Monoclonal antibodies (MAbs) against viral glycoproteins have important diagnostic and therapeutic applications. In most cases, the MAbs specific to viral glycoproteins are raised against intact virus particles. The biosynthesis of viral glycoproteins in heterologous expression systems such as bacteria, yeast, insect or mammalian cells is often problematic due to their low expression level, improper folding and limited stability. To generate MAbs against hantavirus glycoprotein Gc, we have us...

  7. Inhibitory function of adapter-related protein complex 2 alpha 1 subunit in the process of nuclear translocation of human immunodeficiency virus type 1 genome

    International Nuclear Information System (INIS)

    The transfection of human cells with siRNA against adapter-related protein complex 2 alpha 1 subunit (AP2α) was revealed to significantly up-regulate the replication of human immunodeficiency virus type 1 (HIV-1). This effect was confirmed by cell infection with vesicular stomatitis virus G protein-pseudotyped HIV-1 as well as CXCR4-tropic and CCR5-tropic HIV-1. Viral adsorption, viral entry and reverse transcription processes were not affected by cell transfection with siRNA against AP2α. In contrast, viral nuclear translocation as well as the integration process was significantly up-regulated in cells transfected with siRNA against AP2α. Confocal fluorescence microscopy revealed that a subpopulation of AP2α was not only localized in the cytoplasm but was also partly co-localized with lamin B, importin β and Nup153, implying that AP2α negatively regulates HIV-1 replication in the process of nuclear translocation of viral DNA in the cytoplasm or the perinuclear region. We propose that AP2α may be a novel target for disrupting HIV-1 replication in the early stage of the viral life cycle

  8. Use of a Novel Chimeric Mouse Model with a Functionally Active Human Immune System To Study Human Immunodeficiency Virus Type 1 Infection▿

    OpenAIRE

    An, Dong Sung; Poon, Betty; Fang, Raphael Ho Tsong; Weijer, Kees; Blom, Bianca; Spits, Hergen; Chen, Irvin S. Y.; Uittenbogaart, Christel H.

    2007-01-01

    The goal of this study was to develop a small-animal model to study human immunodeficiency virus type 1 (HIV-1) pathogenesis in blood and primary and secondary lymphoid organs. Rag2−/−γc−/− mice that are neonatally injected with human CD34+ cells develop a functional human immune system (HIS), with human hematopoietic cells being found in the thymuses, peripheral blood, spleens, and bone marrow of the animals (hereafter these animals are referred to as HIS-Rag2−/−γc−/− mice). HIS-Rag2−/−γc−/−...

  9. Preparation and characterization of recombinant Llama VHH-human IgGFc chimeric antibody against H5N1 hemagglutinin from avian influenza virus%羊驼抗H5N1血凝素重链可变区-人IgGFc段嵌合抗体的制备和鉴定

    Institute of Scientific and Technical Information of China (English)

    夏立亮; 吴标; 程亚庭; 蔡家麟; 王颖; 赵国屏

    2012-01-01

    To prepare and characterize llama variable domain of heavy chain of heavy-chain antibody-human IgGlFc (VHH-hFc) chimeric antibody against hemagglutinin from H5N1 avian influenza virus, recombinant expression vector pET-22b-VHH23-hFc was constructed and VHH23-hFc chimeric antibody was expressed in E. coli BL2KDE3) strain by IPTG induction. As VHH23-hFc antibody was accumulated in inclusion bodies, two different refolding methods, dialysis and on-column refolding, were compared for the refolding efficacy and the optimal method was adopted for preparation of VHH23-hFc chimeric antibody. The activity and thermal stability of VHH antibodies were tested by ELISA. By using dialysis refolding procedure, VHH23-hFc chimeric antibody has been obtained with higher yield and good quality. The affinity constant of VHH23-hFc chimeric antibody was 2. 24 × 106 mol/L as determined by ELISA. VHH23-hFc chimeric antibody also displayed good thermal stability. The half-life span of VHH23-hFc chimeric antibody in mice was up to 35 hrs, which is comparable to conventional chimeric antibodies. Taken together, our results indicated that VHH23-hFc chimeric antibody against hemagglutinin derived from H5N1 avian influenza virus has been obtained with high activity, good thermal stability as well as longer half-life span, which provides basis for future functional study both in vitro and in vivo.%本研究旨在制备羊驼抗H5N1禽流感病毒的重链抗体可变区-人Fc段嵌合体抗体制备,对所得嵌合抗体进行制备和功能鉴定,为临床应用奠定基础.用pET-22b表达载体构建抗H5N1禽流感病毒羊驼重链可变区(VHH)-人IgG1Fc嵌合基因,以包涵体形式表达VHH23-hFc嵌合抗体蛋白,采用优化的方法复性后,获得高纯度VHH23-hFc嵌合抗体,用ELISA法鉴定嵌合抗体亲和力、热稳定性和小鼠体内的半衰期.结果显示,透析复性后原核表达的抗H5N1禽流感病毒VHH23-hFc嵌合抗体亲和力为2.24×106 mol/L,具有较好

  10. In vivo inactivation of Nef ITAM motif of chimeric simian/human immunodeficiency virus SHIVsbg-YE correlates with absence of increased virulence in chinese rhesus macaques

    International Nuclear Information System (INIS)

    SHIVsbg, expressing Vpu, Tat, Rev, and Env proteins of HIV-1 Lai, was shown to be infectious for rhesus macaques. In this study, we mutated SHIVsbg Nef amino acids 17-18 from RQ to YE, conferring to SHIVsbg-YE the ability to replicate in vitro in unstimulated macaque PBMC. Juvenile macaques inoculated intravenously or orally with SHIVsbg-YE developed persistent infection. All macaques lost weight during the first 17 weeks but recovered afterward. All animals developed a strong HIV-specific humoral immune response. Viruses isolated 2 years postinoculation lost the ability to replicate in unstimulated macaque PBMC. Point mutations or 33-bp-wide deletions in the nef ITAM motif were responsible for this phenotype and correlated with clinical improvement of the infected macaques. These data demonstrate that the ITAM domain is inactivated in animals developing an acute antiviral immune response and may be detrimental to viral replication, perhaps by interfering with other well-conserved functions of SIV Nef protein

  11. Persistence of chicken herpesvirus and retroviral chimeric molecules upon in vivo passage.

    Science.gov (United States)

    Borenshtain, R; Witter, R L; Davidson, I

    2003-01-01

    Mareks disease virus (MDV), a herpesvirus, and avian leucosis virus subgroup J (ALV-J), a retrovirus, were used for experimental coinfection of chickens. Chimeric molecules having sequences of both viruses were detected by the hotspot-combined polymerase chain reaction (HS-cPCR) system. The detection of chimeric molecules provided evidence for avian retroviral inserts in the herpesvirus genome. The persistence of chimeric molecules on in vivo passage served to indicate the infectivity of the recombinant virus. The evaluation of formation and persistence of the chimeric molecules was performed in two trials involving three in vivo passages. The chimeric molecules were identified according to the primer sets, their product length, and pattern. The persistence of chimeric molecules on in vivo passages served as an indication of their ability to replicate in and infect chickens. In the first experimental passage, MDV and ALV-J prototype strains, MD11 and HC-1, were intraperitoneally (i.p.) injected into 1-day-old chicks. The second trial included two passages. Passage II chicks were injected i.p. and passage III chickens were in contact with the chickens of passage II. For passage II, enriched white blood cells from blood samples of chickens from the first trial that had chimeric molecules were injected i.p. into 1-day-old chicks. For passage III, uninfected chicks were included together with the infected chicks. Synthesis evidence for the various species of chimeric molecules was assessed in the tissues of birds of the second trial. DNA was extracted from blood and feathers and analyzed by the hotspot-combined PCR and by pulsed field gel electrophoresis. To overcome the limits of detection, three amplification assays followed by hybridization of the products to specific viral probes were conducted. A variety of chimeric molecules were detected in low concentrations. Five species of chimeric molecules were characterized in blood, tumors, and feathers. Chimeric

  12. SAT Type Foot-and-Mouth Disease (FMD) Chimeric Vaccine Elicits Protection in Pigs

    Science.gov (United States)

    The recent development of infectious cDNA clone technology for foot-and-mouth disease (FMD), Southern African Territories (SAT) viruses has provided a valuable tool for genetic and biological characterization of field and laboratory strains. Recombinant chimeric viruses, containing the capsid-coding...

  13. Chimeric HBcAg virus-like particles presenting a HPV 16 E7 epitope significantly suppressed tumor progression through preventive or therapeutic immunization in a TC-1-grafted mouse model

    Directory of Open Access Journals (Sweden)

    Chu X

    2016-05-01

    Full Text Available Xiaojie Chu,1–3,* Yang Li,1–3,* Qiong Long,1–3 Ye Xia,1–3 Yufeng Yao,1–3 Wenjia Sun,1–3 Weiwei Huang,1–3 Xu Yang,1–3 Cunbao Liu,1–3 Yanbing Ma1–3 1Laboratory of Molecular Immunology, Institute of Medical Biology, Chinese Academy of Medical Science & Peking Union Medical College, 2Yunnan Key Laboratory of Vaccine Research & Development on Severe Infectious Disease, 3Yunnan Engineering Research Center of Vaccine Research and Development on Severe Infectious Disease, Kunming, People’s Republic of China *These authors contributed equally to this work Background: Therapeutic human papillomavirus (HPV vaccines are currently being developed. However, no therapeutic efficacy has been achieved in clinical trials for the treatment of cervical intraepithelial neoplasia or cancer. One of the important issues in increasing vaccine efficacy is determining the best way to enhance tumor antigen-specific cellular immune responses. This study aimed to explore the virus-like particles (VLPs of hepatitis B core antigen (HBcAg as potential therapeutic vaccine carriers and to assess its immunological characteristics.Methods: Chimeric VLPs presenting a HPV 16 cytotoxic T lymphocytes epitope E749–57 (amino acid 49–57 of the E7 protein were prepared using recombinant genes. C57BL/6 mice were immunized with VLPs and grafted with tumor cells TC-1 which is an E7-expressing tumorigenic cell line. The dynamic tumor growth was monitored and anti-tumor immune responses were investigated.Results: Using a preventive strategy, immunization with VLPs resulted in nearly complete suppression of tumor growth. In treatment studies, VLP immunization significantly suppressed the tumor progression in mice carrying 2–3 mm tumors and in those bearing even larger tumors with diameters up to 8–9 mm. The VLP structure was shown to be important to induce vigorous antitumor immunity and effects. In immunized mice, enhanced E749–57-specific cellular immune

  14. Chimeric enzymes with improved cellulase activities

    Science.gov (United States)

    Xu, Qi; Baker, John O; Himmel, Michael E

    2015-03-31

    Nucleic acid molecules encoding chimeric cellulase polypeptides that exhibit improved cellulase activities are disclosed herein. The chimeric cellulase polypeptides encoded by these nucleic acids and methods to produce the cellulases are also described, along with methods of using chimeric cellulases for the conversion of cellulose to sugars such as glucose.

  15. Custom-engineered chimeric foot-and-mouth disease vaccine elicits protective immune responses in pigs

    Science.gov (United States)

    Chimeric foot-and-mouth disease viruses (FMDV) of which the antigenic properties can be readily manipulated is a potentially powerful approach in the control of foot-and-mouth disease (FMD) in sub-Saharan Africa. FMD vaccine application is complicated by the extensive variability of the South Africa...

  16. Serotype Chimeric Human Adenoviruses for Cancer GeneTherapy

    Directory of Open Access Journals (Sweden)

    Akseli Hemminki

    2010-09-01

    Full Text Available Cancer gene therapy consists of numerous approaches where the common denominator is utilization of vectors for achieving therapeutic effect. A particularly potent embodiment of the approach is virotherapy, in which the replication potential of an oncolytic virus is directed towards tumor cells to cause lysis, while normal cells are spared. Importantly, the therapeutic effect of the initial viral load is amplified through viral replication cycles and production of progeny virions. All cancer gene therapy approaches rely on a sufficient level of delivery of the anticancer agent into target cells. Thus,enhancement of delivery to target cells, and reduction of delivery to non-target cells, in an approach called transductional targeting, is attractive. Both genetic and non-genetic retargeting strategies have been utilized. However, in the context of oncolytic viruses, it is beneficial to have the specific modification included in progeny virions and hence genetic modification may be preferable. Serotype chimerism utilizes serotype specific differences in receptor usage, liver tropism and seroprevalence in order to gain enhanced infection of target tissue. This review will focus on serotype chimeric adenoviruses for cancer gene therapy applications.

  17. 以轮状病毒VP6为载体的RV/HBV嵌合蛋白的构建及抗原性研究%Construction of a rotavirus/hepatitis B virus plasmid and the immunogenic analysis of the expressed chimeric proteins

    Institute of Scientific and Technical Information of China (English)

    袁静; 吴绪伟; 郑红梅; 曹向红; 潘小霞; 滕玉梅; 李琦涵; 陈元鼎

    2012-01-01

    Objective To construct a pETP6v carrier vector that expressed rotavirus (RV) VP6 protein and insert a gene fragment encoding the epitope of hepatitis B virus (HBV) S protein that expressed a RV/HBV chimeric protein, and to study the immunogenicity of this chimeric protein and assess its potential as a combined vaccine.Methods Using gene cloning and recombinant techniques,the gene of rotavirus VP6,the group (subgroup) of antigenic protein of the virus,was inserted into plasmid pETL to construct a carrier vector named pETP6v; then,a DNA fragment from HBV S gene that encodes the highly conserved epitope consisting of 21 amino acids (TTPAQGNSMFPSCCCSKPTDG) was inserted into the carrier vector pETP6v.The expression of this rotavirus VP6/HBV S epitope chimeric protein was analyzed in E.coli and further evaluated by ELISA and Western blot.Results A RV/HBV expression plasmid (pETP6/Hs) that carries the HBV S determinant was constructed and the RV/HBV chimeric protein expressed at very high levels in E.coli (about 36.2% of the total bacterial proteins) and the purity of the recombinant protein reached above 90%.The purified chemeric protein could react with anti-HBs serum from HBV-infected individuals and serum from guinea pigs immunized with rotavirus VP6 protein by ELISA and/or Western blot analysis.Conclusions The recombinant expression plasmid pETP6/Hs can be constructed to express chimeric proteins such as RV/HBV with high immunogenicity and reactivity and may be used in the development of RV/HBV and RV/other virus combined vaccines.%目的 构建轮状病毒(rotavirus,RV) VP6载体及携带乙型肝炎病毒(hepatitis B virus,HBV)外源抗原表位的嵌合质粒,进一步探索研发携带HBV抗原表位的重组嵌合疫苗的技术.方法 运用基因克隆和重组技术,构建轮状病毒VP6载体,同时将HBV编码中和抗原表位21个氨基酸的基因序列构建到VP6载体上相应酶切位点,在大肠杆菌中表达嵌合蛋白,并进行相关

  18. Progress in Chimeric Vector and Chimeric Gene Based Cardiovascular Gene Therapy

    Institute of Scientific and Technical Information of China (English)

    HU Chun-Song; YOON Young-sup; ISNER Jeffrey M.; LOSORDO Douglas W.

    2003-01-01

    Gene therapy for cardiovascular diseases has developed from preliminary animal experiments to clinical trials. However, vectors and target genes used currently in gene therapy are mainly focused on viral, nonviral vector and single target gene or monogene. Each vector system has a series of advantages and limitations. Chimeric vectors which combine the advantages of viral and nonviral vector,chimeric target genes which combine two or more target genes and novel gene delivery modes are being developed. In this article, we summarized the progress in chimeric vectors and chimeric genes based cardiovascular gene therapy, which including proliferative or occlusive vascular diseases such as atheroslerosis and restenosis, hypertonic vascular disease such as hypertension and cardiac diseases such as myocardium ischemia, dilated cardiomyopathy and heart failure, even heart transplantation. The development of chimeric vector, chimeric gene and their cardiovascular gene therapy is promising.

  19. Using Chimeric Hypoviruses To Fine-Tune the Interaction between a Pathogenic Fungus and Its Plant Host

    OpenAIRE

    CHEN, BAOSHAN; Geletka, Lynn M.; Nuss, Donald L.

    2000-01-01

    Infectious cDNA clones of mild (CHV1-Euro7) and severe (CHV1-EP713) hypovirus strains responsible for virulence attenuation (hypovirulence) of the chestnut blight fungus Cryphonectria parasitica were used to construct viable chimeric viruses. Differences in virus-mediated alterations of fungal colony morphology, growth rate, and canker morphology were mapped to a region of open reading frame B extending from nucleotides 2,363 to 9,904. By swapping domains within this region, it was possible t...

  20. Blood chimerism in a dizygotic dichorionic pregnancy.

    Science.gov (United States)

    Jang, Ja-Hyun; Jung, Haiyoung; Kim, Jong-Hwa; Park, Won-Soon; Kim, Sun-Hee

    2010-10-01

    Blood chimerism in twins is known to occur through the transfer of hematopoietic stem cells between the fetuses via a common placenta. We present a case of blood chimerism in a dizygotic dichorionic twin pregnancy. The female twin was delivered at 34 weeks of gestation, and the male twin was stillborn. Pathologic examination confirmed dichorionic diamniotic placentas. The karyotype of the female child was obtained using peripheral blood sample, and it revealed a mixture of 46,XX and 46,XY cells (chi 46,XY[13]/46,XX[7]). FISH analysis performed on the buccal cells by using CEP X/Y probe (Abbott Molecular Inc., USA) revealed 100% XX signals (nuc ish Xcen(DXZ1x2)[500]). Gross examination of the external genitalia and abdominal ultrasonography revealed no definitive abnormal findings in relation to sex differentiation. When XX/XY chimerism is present in blood lymphocytes, careful examination of external genitalia and reproductive organs and further studies are required to detect chimerism in non-hematopoetic tissues. This is a rare case of blood chimerism in dichorionic placentas, in contrast to those in monochorionic placentas. PMID:20890086

  1. Chimerism in health, transplantation and autoimmunity

    NARCIS (Netherlands)

    Koopmans, Marije; Kremer Hovinga, Idske Cornelia Lydia

    2009-01-01

    The term “chimerism” originates from Greek mythology and refers to the creature Chimaera, whose body was in front a lion, the back a serpent and the midsection a goat. In medicine, the term chimerism refers to an individual, organ or part consisting of tissues of diverse genetic constitution. Pregna

  2. Capsid proteins from field strains of foot-and-mouth disease virus confer a pathogenic phenotype in cattle on an attenuated, cell-culture-adapted virus

    DEFF Research Database (Denmark)

    Bøtner, Anette; Kakker, Naresh K.; Barbezange, Cyril;

    2011-01-01

    Chimeric foot-and-mouth disease viruses (FMDVs) have been generated from plasmids containing full-length FMDV cDNAs and characterized. The parental virus cDNA was derived from the cell-culture-adapted O1Kaufbeuren B64 (O1K B64) strain. Chimeric viruses, containing capsid coding sequences derived...... region within the O1K B64 strain that inhibits replication in cattle. These chimeric infectious cDNA plasmids provide a basis for the analysis of FMDV pathogenicity and characterization of receptor utilization in vivo....

  3. FACIAL EXPRESSION RECOGNITION WITH THE USE OF CHIMERIC FACE TECHNIQUE

    OpenAIRE

    Menshikova, Galina

    2010-01-01

    The aim of this study was to investigate holistic / feature processing for encoding face expressions employing the chimeric face technique. In the course of our experiment we tested the recognition accuracy of universal and chimeric countenance. As the study has revealed there was a considerable difference between distributions of subject responses depending on the localization of expression features (top / bottom parts of the face). For chimeric face identification accuracy substantially dec...

  4. Chimeric classical swine fever (CSF)-Japanese encephalitis (JE) viral particles as a non-transmissible bivalent marker vaccine candidate against CSF and JE infections

    Science.gov (United States)

    A trans-complemented CSF- JE chimeric viral replicon was constructed using an infectious cDNA clone of the CSF virus (CSFV) Alfort/187 strain. The E2 gene of CSFV Alfort/187 strain was deleted and the resultant plasmid pA187delE2 was inserted by a fragment containing the region coding for a truncate...

  5. Protective and immunological behavior of chimeric yellow fever dengue vaccine.

    Science.gov (United States)

    Halstead, Scott B; Russell, Philip K

    2016-03-29

    Clinical observations from the third year of the Sanofi Pasteur chimeric yellow fever dengue tetravalent vaccine (CYD) trials document both protection and vaccination-enhanced dengue disease among vaccine recipients. Children who were 5 years-old or younger when vaccinated experienced a DENV disease resulting in hospitalization at 5 times the rate of controls. On closer inspection, hospitalized cases among vaccinated seropositives, those at highest risk to hospitalized disease accompanying a dengue virus (DENV) infection, were greatly reduced by vaccination. But, seronegative individuals of all ages after being vaccinated were only modestly protected from mild to moderate disease throughout the entire observation period despite developing neutralizing antibodies at high rates. Applying a simple epidemiological model to the data, vaccinated seronegative individuals of all ages were at increased risk of developing hospitalized disease during a subsequent wild type DENV infection. The etiology of disease in placebo and vaccinated children resulting in hospitalization during a DENV infection, while clinically similar are of different origin. The implications of the observed mixture of DENV protection and enhanced disease in CYD vaccinees are discussed. PMID:26873054

  6. Cloning, expression, and purification of a highly immunogenic recombinant gonadotropin-releasing hormone (GnRH) chimeric peptide.

    Science.gov (United States)

    Xu, Jinshu; Zhu, Zheng; Duan, Peng; Li, Wenjia; Zhang, Yin; Wu, Jie; Hu, Zhuoyi; Roque, Rouel S; Liu, Jingjing

    2006-12-01

    To design an anti-gonadotropin-releasing hormone (GnRH) vaccine capable of eliciting strong immunogenicity, a gene fragment encoding a chimeric peptide was constructed using polymerase chain reaction and ligated into a novel expression vector for recombinant expression in a T7 RNA polymerase-based expression system. The chimeric peptide called GnRH3-hinge-MVP contained three linear repeats of GnRH (GnRH3), a fragment of the human IgG1 hinge region, and a T-cell epitope of measles virus protein (MVP). The expression plasmid contained the GnRH3-hinge-MVP construct ligated to its fusion partner (AnsB-C) via an unique acid labile Asp-Pro linker. The recombinant fusion protein was expressed in an inclusion body in Escherichia coli under IPTG or lactose induction and the target peptide was easily purified using washing of urea and ethanol precipitation. The target chimeric peptide was isolated from the fusion partner following acid hydrolysis and purified using DEAE-Sephacel chromatography. The purified GnRH3-hinge-MVP was determined to be highly homogeneous by IEF analysis and the N-terminal sequencing. Further, immunization of female mice with the recombinant chimeric peptide resulted in generation of high-titer antibodies specific for GnRH. The results showed that GnRH3-hinge-MVP could be considered as a candidate anti-GnRH vaccine. PMID:17064933

  7. Mutations in the Carboxi Terminal Region of E2 Glycoprotein of Classical Swine Fever Virus is Responsible for Viral Attenuation in Swine

    Science.gov (United States)

    We have reported that chimeric virus 319.1 virus containing the E2 glycoprotein gene from Classical Swine Fever Virus (CSFV) vaccine strain CS with the genetic background of virulent CSFV strain Brescia (BIC virus) was attenuated in pigs. To identify the amino acids mediating 319.1 virus attenuation...

  8. Incorporation of chimeric HIV-SIV-Env and modified HIV-Env proteins into HIV pseudovirions

    International Nuclear Information System (INIS)

    Low level incorporation of the viral glycoprotein (Env) into human immunodeficiency virus (HIV) particles is a major drawback for vaccine strategies against HIV/AIDS in which HIV particles are used as immunogen. Within this study, we have examined two strategies aimed at achieving higher levels of Env incorporation into non-infectious pseudovirions (PVs). First, we have generated chimeric HIV/SIV Env proteins containing the truncated C-terminal tail region of simian immunodeficiency virus (SIV)mac239-Env767stop, which mediates strongly increased incorporation of SIV-Env into SIV particles. In a second strategy, we have employed a truncated HIV-Env protein (Env-Tr752N750K) which we have previously demonstrated to be incorporated into HIV virions, generated in infected T-cells, to a higher level than that of Wt-HIV-Env. Although the chimeric HIV/SIV Env proteins were expressed at the cell surface and induced increased levels of cell-cell fusion in comparison to Wt-HIV-Env, they did not exhibit increased incorporation into either HIV-PVs or SIV-PVs. Only Env-Tr752N750K exhibited significantly higher (threefold) levels of incorporation into HIV-PVs, an improvement, which, although not dramatic, is worthwhile for the large-scale preparation of non-infectious PVs for vaccine studies aimed at inducing Env humoral responses

  9. A Live-Attenuated Chimeric Porcine Circovirus Type 2 (PCV2) Vaccine Is Transmitted to Contact Pigs but Is Not Upregulated by Concurrent Infection with Porcine Parvovirus (PPV) and Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) and Is Efficacious in a PCV2b-PRRSV-PPV Challenge Model▿

    OpenAIRE

    Opriessnig, T.; Shen, H. G.; Pal, N; Ramamoorthy, S.; Huang, Y. W.; Lager, K M; Beach, N. M.; Halbur, P G; Meng, X. J.

    2011-01-01

    The live chimeric porcine circovirus type 2 (PCV2) vaccine with the capsid gene of the emerging subtype 2b cloned in the genomic backbone of the nonpathogenic PCV1 is attenuated in vivo and induces protective immunity against PCV2. To further determine the safety and efficacy of this experimental vaccine, we tested for evidence of pig-to-pig transmission by commingling nonvaccinated and vaccinated pigs, determined potential upregulation by simultaneous vaccination and infection with porcine p...

  10. A live-attenuated chimeric porcine circovirus type 2 (PCV2) vaccine is transmitted to contact pigs but is not upregulated by concurrent infection with porcine parvovirus (PPV) and porcine reproductive and respiratory syndrome virus (PRRSV) and is efficacious in a PCV2b-PRRSV-PPV challenge model

    OpenAIRE

    Opriessnig, T.; Shen, H. G.; Pal, N; Ramamoorthy, S.; Huang, Y. W.; Lager, K M; Beach, N. M.; Halbur, P G; Meng, X. J.

    2011-01-01

    The live chimeric porcine circovirus type 2 (PCV2) vaccine with the capsid gene of the emerging subtype 2b cloned in the genomic backbone of the nonpathogenic PCV1 is attenuated in vivo and induces protective immunity against PCV2. To further determine the safety and efficacy of this experimental vaccine, we tested for evidence of pig-to-pig transmission by commingling nonvaccinated and vaccinated pigs, determined potential upregulation by simultaneous vaccination and infection with porcine p...

  11. HIV-1 with multiple CCR5/CXCR4 chimeric receptor use is predictive of immunological failure in infected children.

    Directory of Open Access Journals (Sweden)

    Mariangela Cavarelli

    Full Text Available BACKGROUND: HIV-1 R5 viruses are characterized by a large phenotypic variation, that is reflected by the mode of coreceptor use. The ability of R5 HIV-1 to infect target cells expressing chimeric receptors between CCR5 and CXCR4 (R5(broad viruses, was shown to correlate with disease stage in HIV-1 infected adults. Here, we ask the question whether phenotypic variation of R5 viruses could play a role also in mother-to-child transmission (MTCT of HIV-1 and pediatric disease progression. METHODOLOGY/PRINCIPAL FINDINGS: Viral isolates obtained from a total of 59 HIV-1 seropositive women (24 transmitting and 35 non transmitting and 28 infected newborn children, were used to infect U87.CD4 cells expressing wild type or six different CCR5/CXCR4 chimeric receptors. HIV-1 isolates obtained from newborn infants had predominantly R5(narrow phenotype (n = 20, but R5(broad and R5X4 viruses were also found in seven and one case, respectively. The presence of R5(broad and R5X4 phenotypes correlated significantly with a severe decline of the CD4+ T cells (CDC stage 3 or death within 2 years of age. Forty-three percent of the maternal R5 isolates displayed an R5(broad phenotype, however, the presence of the R5(broad virus was not predictive for MTCT of HIV-1. Of interest, while only 1 of 5 mothers with an R5X4 virus transmitted the dualtropic virus, 5 of 6 mothers carrying R5(broad viruses transmitted viruses with a similar broad chimeric coreceptor usage. Thus, the maternal R5(broad phenotype was largely preserved during transmission and could be predictive of the phenotype of the newborn's viral variant. CONCLUSIONS/SIGNIFICANCE: Our results show that R5(broad viruses are not hampered in transmission. When transmitted, immunological failure occurs earlier than in children infected with HIV-1 of R5(narrow phenotype. We believe that this finding is of utmost relevance for therapeutic interventions in pediatric HIV-1 infection.

  12. Application of functional genomics to the chimeric mouse model of HCV infection: optimization of microarray protocols and genomics analysis

    Directory of Open Access Journals (Sweden)

    Smith Maria W

    2006-05-01

    Full Text Available Abstract Background Many model systems of human viral disease involve human-mouse chimeric tissue. One such system is the recently developed SCID-beige/Alb-uPA mouse model of hepatitis C virus (HCV infection which involves a human-mouse chimeric liver. The use of functional genomics to study HCV infection in these chimeric tissues is complicated by the potential cross-hybridization of mouse mRNA on human oligonucleotide microarrays. To identify genes affected by mouse liver mRNA hybridization, mRNA from identical human liver samples labeled with either Cy3 or Cy5 was compared in the presence and absence of known amounts of mouse liver mRNA labeled in only one dye. Results The results indicate that hybridization of mouse mRNA to the corresponding human gene probe on Agilent Human 22 K oligonucleotide microarray does occur. The number of genes affected by such cross-hybridization was subsequently reduced to approximately 300 genes both by increasing the hybridization temperature and using liver samples which contain at least 80% human tissue. In addition, Real Time quantitative RT-PCR using human specific probes was shown to be a valid method to verify the expression level in human cells of known cross-hybridizing genes. Conclusion The identification of genes affected by cross-hybridization of mouse liver RNA on human oligonucleotide microarrays makes it feasible to use functional genomics approaches to study the chimeric SCID-beige/Alb-uPA mouse model of HCV infection. This approach used to study cross-species hybridization on oligonucleotide microarrays can be adapted to other chimeric systems of viral disease to facilitate selective analysis of human gene expression.

  13. A novel dengue virus serotype 1 vaccine candidate based on Japanese encephalitis virus vaccine strain SA14-14-2 as the backbone.

    Science.gov (United States)

    Yang, Huiqiang; Li, Zhushi; Lin, Hua; Wang, Wei; Yang, Jian; Liu, Lina; Zeng, Xianwu; Wu, Yonglin; Yu, Yongxin; Li, Yuhua

    2016-06-01

    To develop a potential dengue vaccine candidate, a full-length cDNA clone of a novel chimeric virus was constructed using recombinant DNA technology, with Japanese encephalitis virus (JEV) vaccine strain SA14-14-2 as the backbone, with its premembrane (prM) and envelope (E) genes substituted by their counterparts from dengue virus type 1 (DENV1). The chimeric virus (JEV/DENV1) was successfully recovered from primary hamster kidney (PHK) cells by transfection with the in vitro transcription products of JEV/DENV1 cDNA and was identified by complete genome sequencing and immunofluorescent staining. No neuroinvasiveness of this chimeric virus was observed in mice inoculated by the subcutaneous route (s.c.) or by the intraperitoneal route (i.p.), while some neurovirulence was displayed in mice that were inoculated directly by the intracerebral route (i.c.). The chimeric virus was able to stimulate high-titer production of antibodies against DENV1 and provided protection against lethal challenge with neuroadapted dengue virus in mice. These results suggest that the chimeric virus is a promising dengue vaccine candidate. PMID:26976137

  14. The Glycoprotein and the Matrix Protein of Rabies Virus Affect Pathogenicity by Regulating Viral Replication and Facilitating Cell-to-Cell Spread▿

    OpenAIRE

    Pulmanausahakul, Rojjanaporn; Li, Jianwei; Schnell, Matthias J.; Dietzschold, Bernhard

    2007-01-01

    While the glycoprotein (G) of rabies virus (RV) is known to play a predominant role in the pathogenesis of rabies, the function of the RV matrix protein (M) in RV pathogenicity is not completely clear. To further investigate the roles of these proteins in viral pathogenicity, we constructed chimeric recombinant viruses by exchanging the G and M genes of the attenuated SN strain with those of the highly pathogenic SB strain. Infection of mice with these chimeric viruses revealed a significant ...

  15. Do chimeric sponges have improved chances of survival?

    OpenAIRE

    Maldonado, Manuel

    1998-01-01

    It has been suggested that the capacity of fusion with both kin and genetically unrelated conspecifics to form chimeras (i.e. individuals with a mixture of genetically different cells) is evolutionarily retained In several phyla because the resulting organism obtains some selective advantages over non-chimeric conspecifics. Many demosponges are known to have fusible larvae that form young chimeric sponges, but the ecological and evolutionary significance of this phenom...

  16. A recombinant rabies virus expressing vesicular stomatitis virus glycoprotein fails to protect against rabies virus infection

    OpenAIRE

    Foley, Heather D.; McGettigan, James P.; Siler, Catherine A.; Dietzschold, Bernhard; Schnell, Matthias J.

    2000-01-01

    To investigate the importance of the rabies virus (RV) glycoprotein (G) in protection against rabies, we constructed a recombinant RV (rRV) in which the RV G ecto- and transmembrane domains were replaced with the corresponding regions of vesicular stomatitis virus (VSV) glycoprotein (rRV-VSV-G). We were able to recover rRV-VSV-G and found that particle production was equal to rRV. However, the budding of the chimeric virus was delayed and infectious titers were red...

  17. Generation and biological characterization of chimeric viruses which substituted ORF1a, ORF1b, ORF2-7 between highly pathogenic porcine reproductive and respiratory virus and its attenuated vaccine virus%高致病性猪繁殖与呼吸综合征病毒强弱毒ORF1a、ORF1b、ORF2-ORF7片段互换嵌合病毒的构建及其生物学特性的分析

    Institute of Scientific and Technical Information of China (English)

    姜一峰; 周艳君; 王亚欣; 朱建平; 徐彦召; 童武; 虞凌雪; 童光志

    2012-01-01

    N4-FI12 with ORFla, ORFlb or ORF2-7 from HuN4-F5), respectively. The growth kinetics showed that rHuN4-F5-ORFla had significantly higher titer than its parental virus rHuN4-F5, and rHuN4-F112-ORFla had significantly lower titer than its parental virus rHuN4-F112, while other chimeric viruses had similar growth curve with their parental viruses on Marc-145 cell. Based on our research, we conclude that ORFla region plays a very important role in virus adaptation on Marc-145 cell.

  18. Priming B cell-mediated anti-HIV envelope responses by vaccination allows for the long-term control of infection in macaques exposed to a R5-tropic SHIV

    International Nuclear Information System (INIS)

    The potential of vaccine-elicited anti-HIV envelope antibodies to control HIV-infection was evaluated by immunizing macaques with the HIV envelope protein and transiently depleting them of their CD8+ cells before intravenous challenge with the pathogenic CCR5-tropic SIV/HIV chimeric virus, SHIVSF162P4. Although sterilizing immunity was not achieved, all vaccinated animals effectively controlled infection and remained free of disease for the duration of observation (over 3 years). In contrast, during the same period, the control animals progressed to disease. Both the vaccinees and the controls developed robust cell-mediated antiviral and neutralizing antibody responses following infection. A comparative analysis of these responses suggests that the more effective long-term control of infection by the vaccinated animals is due to the more rapid development of anti-HIV envelope antibodies. These studies suggest that priming by vaccination of B cell anti-HIV envelope responses maybe crucial for the long-term control of HIV infection

  19. A Simple Methodology for Conversion of Mouse Monoclonal Antibody to Human-Mouse Chimeric Form

    Directory of Open Access Journals (Sweden)

    Vinh T. Dang

    2013-01-01

    Full Text Available Passive immunotherapy has mainly been used as a therapy against cancer and inflammatory conditions. Recent studies have shown that monoclonal antibody-(mAb- based passive immunotherapy is a promising approach to combat virus infection. Specific mouse mAbs can be routinely generated in large amounts with the use of hybridoma technology but these cannot be used for therapy in human beings due to their immunogenicity. Therefore, the development of chimeric and humanized mAbs is important for therapeutic purpose. This is facilitated by a variety of molecular techniques like recombinant DNA technology and the better understanding of the structure and function of antibody. The human-mouse chimeric forms allow detailed analysis of the mechanism of inhibition and the potential for therapeutic applications. Here, a step-by-step description of the conversion process will be described. The commercial availability of the reagents required in each step means that this experimentation can be easily set up in research laboratories.

  20. Chimeric piggyBac transposases for genomic targeting in human cells.

    Science.gov (United States)

    Owens, Jesse B; Urschitz, Johann; Stoytchev, Ilko; Dang, Nong C; Stoytcheva, Zoia; Belcaid, Mahdi; Maragathavally, Kommineni J; Coates, Craig J; Segal, David J; Moisyadi, Stefan

    2012-08-01

    Integrating vectors such as viruses and transposons insert transgenes semi-randomly and can potentially disrupt or deregulate genes. For these techniques to be of therapeutic value, a method for controlling the precise location of insertion is required. The piggyBac (PB) transposase is an efficient gene transfer vector active in a variety of cell types and proven to be amenable to modification. Here we present the design and validation of chimeric PB proteins fused to the Gal4 DNA binding domain with the ability to target transgenes to pre-determined sites. Upstream activating sequence (UAS) Gal4 recognition sites harbored on recipient plasmids were preferentially targeted by the chimeric Gal4-PB transposase in human cells. To analyze the ability of these PB fusion proteins to target chromosomal locations, UAS sites were randomly integrated throughout the genome using the Sleeping Beauty transposon. Both N- and C-terminal Gal4-PB fusion proteins but not native PB were capable of targeting transposition nearby these introduced sites. A genome-wide integration analysis revealed the ability of our fusion constructs to bias 24% of integrations near endogenous Gal4 recognition sequences. This work provides a powerful approach to enhance the properties of the PB system for applications such as genetic engineering and gene therapy. PMID:22492708

  1. Protection of Mice from Lethal Endotoxemia by Chimeric Human BPI-Fcγ1 Gene Delivery

    Institute of Scientific and Technical Information of China (English)

    Chen Li; Jing Li; Zhe Lv; Xinghua Guo; Qinghua Chen; Qingli Kong; Yunqing An

    2006-01-01

    To evaluate the potentiality of applying gene therapy to endotoxemia in high-risk patients, we investigated the effects of transferring an adeno-associated virus serotype 2 (AAV2)-mediated BPI-Fcγ1 gene on protecting mice from challenge of lethal endotoxin. The chimeric BPI-Fcγ1 gene consists of two parts, one encods functional N-terminus (1 to 199 amino acidic residues) of human BPI, which is a bactericidal/permeability-increasing protein,and the other encodes Fc segment of human immunoglobulin G1 (Fcγ1). Our results indicated that the target protein could be expressed and secreted into the serum of the gene-transferred mice. After lethal endotoxin challenge, the levels of endotoxin and TNF-α in the gene-transferred mice were decreased. The survival rate of the BPI-Fcγ1 gene-transferred mice was markedly increased. Our data suggest that AAV2-mediated chimeric BPI-Fcγ1 gene delivery can potentially be used clinically for the protection and treatment of endotoxemia and endotoxic shock in high-risk individuals.

  2. Human immunodeficiency virus, herpes virus infections, and pulmonary vascular disease

    OpenAIRE

    Flores, Sonia C.; Almodovar, Sharilyn

    2013-01-01

    The following state-of-the-art seminar was delivered as part of the Aspen Lung Conference on Pulmonary Hypertension and Vascular Diseases held in Aspen, Colorado in June 2012. This paper will summarize the lecture and present results from a nonhuman primate model of infection with Simian (Human) Immunodeficiency Virus - nef chimeric virions as well as the idea that polymorphisms in the HIV-1 nef gene may be driving the immune response that results in exuberant inflammation and aberrant endoth...

  3. Chimeric autologous/allogeneic constructs for skin regeneration.

    Science.gov (United States)

    Rasmussen, Cathy Ann; Tam, Joshua; Steiglitz, Barry M; Bauer, Rebecca L; Peters, Noel R; Wang, Ying; Anderson, R Rox; Allen-Hoffmann, B Lynn

    2014-08-01

    The ideal treatment for severe cutaneous injuries would eliminate the need for autografts and promote fully functional, aesthetically pleasing autologous skin regeneration. NIKS progenitor cell-based skin tissues have been developed to promote healing by providing barrier function and delivering wound healing factors. Independently, a device has recently been created to "copy" skin by harvesting full-thickness microscopic tissue columns (MTCs) in lieu of autografts traditionally harvested as sheets. We evaluated the feasibility of combining these two technologies by embedding MTCs in NIKS-based skin tissues to generate chimeric autologous/allogeneic constructs. Chimeric constructs have the potential to provide immediate wound coverage, eliminate painful donor site wounds, and promote restoration of a pigmented skin tissue possessing hair follicles, sweat glands, and sebaceous glands. After MTC insertion, chimeric constructs and controls were reintroduced into air-interface culture and maintained in vitro for several weeks. Tissue viability, proliferative capacity, and morphology were evaluated after long-term culture. Our results confirmed successful MTC insertion and integration, and demonstrated the feasibility of generating chimeric autologous/allogeneic constructs that preserved the viability, proliferative capacity, and structure of autologous pigmented skin. These feasibility studies established the proof-of-principle necessary to further develop chimeric autologous/allogeneic constructs for the treatment of complex skin defects. PMID:25102552

  4. Developmental competence of porcine chimeric embryos produced by aggregation

    DEFF Research Database (Denmark)

    Li, Juan; Jakobsen, Jannik E.; Xiong, Qiang;

    2015-01-01

    either by parthenogenetic activation (PA) or handmade cloning (HMC). Results showed that the developmental competence of chimeric embryos, evaluated based on their blastocyst rate and total cell number per blastocyst, was increased when two whole 2-cell stage embryos (PA or HMC) were aggregated. In...... comparison, when two blastomeres were aggregated, the developmental competence of the chimeric embryos decreased if the blastomeres were either from PA or from HMC embryos, but not if they were from different sources, i.e. one PA and one HMC blastomere. To evaluate the cell contribution in embryo formation......The purpose of our study was to compare the developmental competence and blastomere allocation of porcine chimeric embryos formed by micro-well aggregation. Chimeras were created by aggregating either two blastomeres originating from 2-cell embryos or two whole embryos, where embryos were produced...

  5. Study of cancer-specific chimeric promoters induced by irradiation

    International Nuclear Information System (INIS)

    Objective: To combine the radio-inducible CArG element with cancer-specific human telomerase reverse transcriptase (hTERT) gene promoter, and to construct the novel chimeric promoters. Methods: The synthetic hTERT promoters containing different number of radio-inducible CArG elements were constructed, and the activities of the promoters in the cancer cells (HeLa, A549, and MHCC97 cells) and nomal cells (hEL cells) were detected by using luciferase-reporter assays after the treatment of irradiation (a single or fractionated irradiation dose). Results: Synthetic promoter containing 6 repeated CArG units was better in radio-inducibility than any other promoters containing different number of CArG units, and nearly maximum levels obtained at 4-6 Gy. The very low activities of the chimeric promoters could be detected in normal hEL cells. A similar level of reporter gene expression was observed after 3 fractionated doses of 2 Gy compared with a single dose of 6 Gy in cancer cells. Conclusions: The cancer-specific chimeric promoter containing 6 CArG elements showes the best radio-response, and the chimeric promoter system has the potential in cancer gene therapy. (authors)

  6. HCV prototype vaccine based on hepatitis B core virus-like particles

    OpenAIRE

    Marija Mihailova

    2008-01-01

    HCV prototype vaccine based on hepatitis B core virus-like particles Abstract In the current study the C-terminally truncated HBc expression vectors were used for exposure of different hepatitis C virus (HCV) protein (core, E2, and NS3) fragments. All created chimeric constructs directed high level of recombinant protein synthesis in E.coli. However, not all chimeric proteins were able to self-assemble into virus-like particles (VLPs). HBcCterm/HVR1tetramer VLPs turned ou...

  7. CONSTRUCTION AND EXPRESSION OF A HUMAN-MOUSE CHIMERIC ANTIBODY AGAINST HUMAN BLADDER CANCER

    Institute of Scientific and Technical Information of China (English)

    白银; 王琰; 周丽君; 俞莉章

    2001-01-01

    To construct and express a human-mouse chimeric antibody against human bladder cancer. Method: The variable region genes of anti-human bladder cancer monoclonal antibody BDI-1 were cloned by RT-PCR. A human-mouse chimeric antibody expression vector was constructed and transfected into CHO cells. The chimeric antibody against bladder cancer was expressed and characterized. Result: Eukaryotic expression vector of the chimeric antibody against human bladder carcinoma was successfully constructed, and was expressed in eukaryotic cells; the expressed chimeric antibody ch-BDI showed same specificity as its parent McAb against human bladder cancer cells. Conclusion: The constructed chimeric antibody was expressed successfully in eukaryotic cells, and the chimeric antibody had desired affinity against human bladder cancer cells.

  8. Live virus vaccines based on a yellow fever vaccine backbone: Standardized template with key considerations for a risk/benefit assessment

    OpenAIRE

    Monath, Thomas P.; Seligman, Stephen J.; Robertson, James S; Guy, Bruno; Hayes, Edward B.; Condit, Richard C.; Excler, Jean Louis; Mac, Lisa Marie; Carbery, Baevin; Chen, Robert T.

    2014-01-01

    The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety of live, recombinant viral vaccines incorporating genes from heterologous viruses inserted into the backbone of another virus (so-called "chimeric virus vaccines"). Many viral vector vaccines are in advanced clinical trials. The first such vaccine to be approved for mark...

  9. Chimeric Mice with Competent Hematopoietic Immunity Reproduce Key Features of Severe Lassa Fever.

    Science.gov (United States)

    Oestereich, Lisa; Lüdtke, Anja; Ruibal, Paula; Pallasch, Elisa; Kerber, Romy; Rieger, Toni; Wurr, Stephanie; Bockholt, Sabrina; Pérez-Girón, José V; Krasemann, Susanne; Günther, Stephan; Muñoz-Fontela, César

    2016-05-01

    Lassa fever (LASF) is a highly severe viral syndrome endemic to West African countries. Despite the annual high morbidity and mortality caused by LASF, very little is known about the pathophysiology of the disease. Basic research on LASF has been precluded due to the lack of relevant small animal models that reproduce the human disease. Immunocompetent laboratory mice are resistant to infection with Lassa virus (LASV) and, to date, only immunodeficient mice, or mice expressing human HLA, have shown some degree of susceptibility to experimental infection. Here, transplantation of wild-type bone marrow cells into irradiated type I interferon receptor knockout mice (IFNAR-/-) was used to generate chimeric mice that reproduced important features of severe LASF in humans. This included high lethality, liver damage, vascular leakage and systemic virus dissemination. In addition, this model indicated that T cell-mediated immunopathology was an important component of LASF pathogenesis that was directly correlated with vascular leakage. Our strategy allows easy generation of a suitable small animal model to test new vaccines and antivirals and to dissect the basic components of LASF pathophysiology. PMID:27191716

  10. Chimeric Mice with Competent Hematopoietic Immunity Reproduce Key Features of Severe Lassa Fever.

    Directory of Open Access Journals (Sweden)

    Lisa Oestereich

    2016-05-01

    Full Text Available Lassa fever (LASF is a highly severe viral syndrome endemic to West African countries. Despite the annual high morbidity and mortality caused by LASF, very little is known about the pathophysiology of the disease. Basic research on LASF has been precluded due to the lack of relevant small animal models that reproduce the human disease. Immunocompetent laboratory mice are resistant to infection with Lassa virus (LASV and, to date, only immunodeficient mice, or mice expressing human HLA, have shown some degree of susceptibility to experimental infection. Here, transplantation of wild-type bone marrow cells into irradiated type I interferon receptor knockout mice (IFNAR-/- was used to generate chimeric mice that reproduced important features of severe LASF in humans. This included high lethality, liver damage, vascular leakage and systemic virus dissemination. In addition, this model indicated that T cell-mediated immunopathology was an important component of LASF pathogenesis that was directly correlated with vascular leakage. Our strategy allows easy generation of a suitable small animal model to test new vaccines and antivirals and to dissect the basic components of LASF pathophysiology.

  11. Chimeric Mice with Competent Hematopoietic Immunity Reproduce Key Features of Severe Lassa Fever

    Science.gov (United States)

    Oestereich, Lisa; Lüdtke, Anja; Ruibal, Paula; Pallasch, Elisa; Kerber, Romy; Rieger, Toni; Wurr, Stephanie; Bockholt, Sabrina; Krasemann, Susanne

    2016-01-01

    Lassa fever (LASF) is a highly severe viral syndrome endemic to West African countries. Despite the annual high morbidity and mortality caused by LASF, very little is known about the pathophysiology of the disease. Basic research on LASF has been precluded due to the lack of relevant small animal models that reproduce the human disease. Immunocompetent laboratory mice are resistant to infection with Lassa virus (LASV) and, to date, only immunodeficient mice, or mice expressing human HLA, have shown some degree of susceptibility to experimental infection. Here, transplantation of wild-type bone marrow cells into irradiated type I interferon receptor knockout mice (IFNAR-/-) was used to generate chimeric mice that reproduced important features of severe LASF in humans. This included high lethality, liver damage, vascular leakage and systemic virus dissemination. In addition, this model indicated that T cell-mediated immunopathology was an important component of LASF pathogenesis that was directly correlated with vascular leakage. Our strategy allows easy generation of a suitable small animal model to test new vaccines and antivirals and to dissect the basic components of LASF pathophysiology. PMID:27191716

  12. High affinity mouse-human chimeric Fab against Hepatitis B surface antigen

    Institute of Scientific and Technical Information of China (English)

    Biplab Bose; Navin Khanna; Subrat K Acharya; Subrata Sinha

    2005-01-01

    AIM: Passive immunotherapy using antibody against hepatitis B surface antigen (HBsAg) has been advocated in certain cases of Hepatitis B infection. We had earlier reported on the cloning and expression of a high affinity scFv derived from a mouse monoclonal (5S) against HBsAg. However this mouse antibody cannot be used for therapeutic purposes as it may elicit anti-mouse immune responses. Chimerization by replacing mouse constant domains with human ones can reduce the immunogenicity of this antibody.METHODS: We cloned the VH and VL genes of this mouse antibody; and fused them with CH1 domain of human IgG1 and CL domain of human kappa chain respectively. These chimeric genes were cloned into a phagemid vector. After initial screening using the phage display system, the chimeric Fab was expressed in soluble form in E. Coli.RESULTS: The chimeric Fab was purified from the bacterial periplasmic extract. We characterized the chimeric Fab using several in vitro techniques and it was observed that the chimeric molecule retained the high affinity and specificity of the original mouse monoclonal.This chimeric antibody fragment was further expressed in different strains of E> coli to increase the yield.CONCLUSION: We have generated a mouse-human chimeric Fab against HBsAg without any significant loss in binding and epitope specificity. This chimeric Fab fragment can be further modified to generate a fulllength chimeric antibody for therapeutic uses.

  13. Design of chimeric antigen receptors with integrated controllable transient functions

    OpenAIRE

    Alexandre Juillerat; Alan Marechal; Jean-Marie Filhol; Julien Valton; Aymeric Duclert; Laurent Poirot; Philippe Duchateau

    2016-01-01

    The ability to control T cells engineered to permanently express chimeric antigen receptors (CARs) is a key feature to improve safety. Here, we describe the development of a new CAR architecture with an integrated switch-on system that permits to control the CAR T-cell function. This system offers the advantage of a transient CAR T-cell for safety while letting open the possibility of multiple cytotoxicity cycles using a small molecule drug.

  14. Design of chimeric antigen receptors with integrated controllable transient functions.

    Science.gov (United States)

    Juillerat, Alexandre; Marechal, Alan; Filhol, Jean-Marie; Valton, Julien; Duclert, Aymeric; Poirot, Laurent; Duchateau, Philippe

    2016-01-01

    The ability to control T cells engineered to permanently express chimeric antigen receptors (CARs) is a key feature to improve safety. Here, we describe the development of a new CAR architecture with an integrated switch-on system that permits to control the CAR T-cell function. This system offers the advantage of a transient CAR T-cell for safety while letting open the possibility of multiple cytotoxicity cycles using a small molecule drug. PMID:26750734

  15. Chimeric Proteins to Detect DNA Damage and Mismatches

    Energy Technology Data Exchange (ETDEWEB)

    McCutchen-Maloney, S; Malfatti, M; Robbins, K M

    2002-01-14

    The goal of this project was to develop chimeric proteins composed of a DNA mismatch or damage binding protein and a nuclease, as well as methods to detect DNA mismatches and damage. We accomplished this through protein engineering based on using polymerase chain reactions (PCRs) to create chimeras with novel functions for damage and mismatch detection. This project addressed fundamental questions relating to disease susceptibility and radiation-induced damage in cells. It also supported and enhanced LLNL's competency in the emerging field of proteomics. In nature, DNA is constantly being subjected to damaging agents such as exposure to ultraviolet (UV) radiation and various environmental and dietary carcinogens. If DNA damage is not repaired however, mutations in DNA result that can eventually manifest in cancer and other diseases. In addition to damage-induced DNA mutations, single nucleotide polymorphisms (SNPs), which are variations in the genetic sequence between individuals, may predispose some to disease. As a result of the Human Genome Project, the integrity of a person's DNA can now be monitored. Therefore, methods to detect DNA damage, mutations, and SNPs are useful not only in basic research but also in the health and biotechnology industries. Current methods of detection often use radioactive labeling and rely on expensive instrumentation that is not readily available in many research settings. Our methods to detect DNA damage and mismatches employ simple gel electrophoresis and flow cytometry, thereby alleviating the need for radioactive labeling and expensive equipment. In FY2001, we explored SNP detection by developing methods based on the ability of the chimeric proteins to detect mismatches. Using multiplex assays with flow cytometry and fluorescent beads to which the DNA substrates where attached, we showed that several of the chimeras possess greater affinity for damaged and mismatched DNA than for native DNA. This affinity was

  16. Construction and Immunological Evaluation of Multivalent Hepatitis B Virus (HBV) Core Virus-Like Particles Carrying HBV and HCV Epitopes▿

    OpenAIRE

    Sominskaya, Irina; Skrastina, Dace; Dislers, Andris; Vasiljev, Denis; Mihailova, Marija; Ose, Velta; Dreilina, Dzidra; Pumpens, Paul

    2010-01-01

    A multivalent vaccine candidate against hepatitis B virus (HBV) and hepatitis C virus (HCV) infections was constructed on the basis of HBV core (HBc) virus-like particles (VLPs) as carriers. Chimeric VLPs that carried a virus-neutralizing HBV pre-S1 epitope corresponding to amino acids (aa) 20 to 47 in the major immunodominant region (MIR) and a highly conserved N-terminal HCV core epitope corresponding to aa 1 to 60 at the C terminus of the truncated HBcΔ protein (N-terminal aa 1 to 144 of f...

  17. High-Level Systemic Expression of Conserved Influenza Epitope in Plants on the Surface of Rod-Shaped Chimeric Particles

    Directory of Open Access Journals (Sweden)

    Natalia V. Petukhova

    2014-04-01

    Full Text Available Recombinant viruses based on the cDNA copy of the tobacco mosaic virus (TMV genome carrying different versions of the conserved M2e epitope from influenza virus A cloned into the coat protein (CP gene were obtained and partially characterized by our group previously; cysteines in the human consensus M2e sequence were changed to serine residues. This work intends to show some biological properties of these viruses following plant infections. Agroinfiltration experiments on Nicotiana benthamiana confirmed the efficient systemic expression of M2e peptides, and two point amino acid substitutions in recombinant CPs significantly influenced the symptoms and development of viral infections. Joint expression of RNA interference suppressor protein p19 from tomato bushy stunt virus (TBSV did not affect the accumulation of CP-M2e-ser recombinant protein in non-inoculated leaves. RT-PCR analysis of RNA isolated from either infected leaves or purified TMV-M2e particles proved the genetic stability of TMV‑based viral vectors. Immunoelectron microscopy of crude plant extracts demonstrated that foreign epitopes are located on the surface of chimeric virions. The rod‑shaped geometry of plant-produced M2e epitopes is different from the icosahedral or helical filamentous arrangement of M2e antigens on the carrier virus-like particles (VLP described earlier. Thereby, we created a simple and efficient system that employs agrobacteria and plant viral vectors in order to produce a candidate broad-spectrum flu vaccine.

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

    Directory of Open Access Journals (Sweden)

    Lin Na-Sheng

    2007-09-01

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

  19. Chimeras taking shape: potential functions of proteins encoded by chimeric RNA transcripts.

    Science.gov (United States)

    Frenkel-Morgenstern, Milana; Lacroix, Vincent; Ezkurdia, Iakes; Levin, Yishai; Gabashvili, Alexandra; Prilusky, Jaime; Del Pozo, Angela; Tress, Michael; Johnson, Rory; Guigo, Roderic; Valencia, Alfonso

    2012-07-01

    Chimeric RNAs comprise exons from two or more different genes and have the potential to encode novel proteins that alter cellular phenotypes. To date, numerous putative chimeric transcripts have been identified among the ESTs isolated from several organisms and using high throughput RNA sequencing. The few corresponding protein products that have been characterized mostly result from chromosomal translocations and are associated with cancer. Here, we systematically establish that some of the putative chimeric transcripts are genuinely expressed in human cells. Using high throughput RNA sequencing, mass spectrometry experimental data, and functional annotation, we studied 7424 putative human chimeric RNAs. We confirmed the expression of 175 chimeric RNAs in 16 human tissues, with an abundance varying from 0.06 to 17 RPKM (Reads Per Kilobase per Million mapped reads). We show that these chimeric RNAs are significantly more tissue-specific than non-chimeric transcripts. Moreover, we present evidence that chimeras tend to incorporate highly expressed genes. Despite the low expression level of most chimeric RNAs, we show that 12 novel chimeras are translated into proteins detectable in multiple shotgun mass spectrometry experiments. Furthermore, we confirm the expression of three novel chimeric proteins using targeted mass spectrometry. Finally, based on our functional annotation of exon organization and preserved domains, we discuss the potential features of chimeric proteins with illustrative examples and suggest that chimeras significantly exploit signal peptides and transmembrane domains, which can alter the cellular localization of cognate proteins. Taken together, these findings establish that some chimeric RNAs are translated into potentially functional proteins in humans. PMID:22588898

  20. Construction, purification, and characterization of a chimeric TH1 antagonist

    Directory of Open Access Journals (Sweden)

    Javier-González Luís

    2006-05-01

    Full Text Available Abstract Background TH1 immune response antagonism is a desirable approach to mitigate some autoimmune and inflammatory reactions during the course of several diseases where IL-2 and IFN-γ are two central players. Therefore, the neutralization of both cytokines could provide beneficial effects in patients suffering from autoimmune or inflammatory illnesses. Results A chimeric antagonist that can antagonize the action of TH1 immunity mediators, IFN-γ and IL-2, was designed, engineered, expressed in E. coli, purified and evaluated for its in vitro biological activities. The TH1 antagonist molecule consists of the extracellular region for the human IFNγ receptor chain 1 fused by a four-aminoacid linker peptide to human 60 N-terminal aminoacid residues of IL-2. The corresponding gene fragments were isolated by RT-PCR and cloned in the pTPV-1 vector. E. coli (W3110 strain was transformed with this vector. The chimeric protein was expressed at high level as inclusion bodies. The protein was partially purified by pelleting and washing. It was then solubilized with strong denaturant and finally refolded by gel filtration. In vitro biological activity of chimera was demonstrated by inhibition of IFN-γ-dependent HLA-DR expression in Colo 205 cells, inhibition of IFN-γ antiproliferative effect on HEp-2 cells, and by a bidirectional effect in assays for IL-2 T-cell dependent proliferation: agonism in the absence versus inhibition in the presence of IL-2. Conclusion TH1 antagonist is a chimeric protein that inhibits the in vitro biological activities of human IFN-γ, and is a partial agonist/antagonist of human IL-2. With these attributes, the chimera has the potential to offer a new opportunity for the treatment of autoimmune and inflammatory diseases.

  1. Chimeric creatures in Greek mythology and reflections in science.

    Science.gov (United States)

    Bazopoulou-Kyrkanidou, E

    2001-04-15

    "The Chimaera" in Homer's Iliad, "was of divine stock, not of men, in the forepart a lion, in the hinder a serpent, and in the midst a goat, ellipsis Bellerophon slew her, trusting in the signs of the gods." In Hesiod's Theogony it is emphasized that "Chimaera ellipsis had three heads, one of a grim-eyed lion, another of a goat, and another of a snakeellipsis". In addition to this interspecies animal chimera, human/animal chimeras are referred to in Greek mythology, preeminent among them the Centaurs and the Minotaur. The Centaurs, as horse/men, first appear in Geometric and early Archaic art, but in the literature not until early in the fifth century B.C. The bullheaded-man Minotaur, who is not certainly attested in the literary evidence until circa 500 B.C., first appears in art about 650 B.C. Attempts, in the fourth century B.C. and thereafter, to rationalize their mythical appearance were in vain; their chimeric nature retained its fascinating and archetypal form over the centuries. Early in the 1980s, experimental sheep/goat chimeras were produced removing the reproductive barrier between these two animal species. Late in the 1990s, legal, political, ethical, and moral fights loomed over a patent bid on human/animal chimeras. Chimeric technology is recently developed; however, the concept of chimerism has existed in literary and artistic form in ancient mythology. This is yet another example where art and literature precede scientific research and development. PMID:11337752

  2. Chimeric elk/mouse prion proteins in transgenic mice

    OpenAIRE

    Tamguney, G; Giles, K; Oehler, A.; Johnson, NL; DeArmond, SJ; Prusiner, SB

    2013-01-01

    Chronic wasting disease (CWD) of deer and elk is a highly communicable neurodegenerative disorder caused by prions. Investigations of CWD are hampered by slow bioassays in transgenic (Tg) mice. Towards the development of Tg mice that will be more susceptible to CWD prions, we created a series of chimeric elk/mouse transgenes that encode the N terminus of elk PrP (ElkPrP) up to residue Y168 and the C terminus of mouse PrP (MoPrP) beyond residue 169 (mouse numbering), designated Elk3M(SNIVVK). ...

  3. Authentic display of a cholera toxin epitope by chimeric type 1 fimbriae

    DEFF Research Database (Denmark)

    Stentebjerg-Olesen, Bodil; Pallesen, Lars; Jensen, Lars Bogø;

    1997-01-01

    inserted. Several of the chosen positions seemed amenable even for large foreign inserts; the chimeric proteins were exposed on the bacterial surface and the cholera toxin epitope was authentically displayed, i.e. it was recognized on bacteria by specific antiserum. Display of chimeric fimbriae was tested...

  4. Authentic display of a cholera toxin epitope by chimeric type 1 fimbriae

    DEFF Research Database (Denmark)

    Stentebjerg-Olesen, Bodil; Pallesen, Lars; Jensen, Lars Bogø; Christiansen, Gunnar; Klemm, Per

    inserted. Several of the chosen positions seemed amenable even for large foreign inserts; the chimeric proteins were exposed on the bacterial surface and the cholera toxin epitope was authentically displayed, i.e. it was recognized on bacteria by specific antiserum. Display of chimeric fimbriae was tested...

  5. High-resolution air quality simulation over Europe with the chemistry transport model CHIMERE

    Directory of Open Access Journals (Sweden)

    E. Terrenoire

    2015-01-01

    The results suggest that future work should focus on the development of national bottom-up emission inventories including a better account for semi-volatile organic compounds and their conversion to SOA, the improvement of the CHIMERE urban parameterization, the introduction into CHIMERE of the coarse nitrate chemistry and an advanced parameterization accounting for windblown dust emissions.

  6. The Construction of Chimeric T-Cell Receptor with Spacer Base of Modeling Study of VHH and MUC1 Interaction

    OpenAIRE

    Nazanin Pirooznia; Sadegh Hasannia; Majid Taghdir; Fatemeh Rahbarizadeh; Morteza Eskandani

    2011-01-01

    Adaptive cell immunotherapy with the use of chimeric receptors leads to the best and most specific response against tumors. Chimeric receptors consist of a signaling fragment, extracellular spacer, costimulating domain, and an antibody. Antibodies cause immunogenicity; therefore, VHH is a good replacement for ScFv in chimeric receptors. Since peptide sequences have an influence on chimeric receptors, the effect of peptide domains on each other's conformation were investigated. CD3Zeta, CD28, ...

  7. MHC-mismatched mixed chimerism augments thymic regulatory T-cell production and prevents relapse of EAE in mice

    OpenAIRE

    Wu, Limin; Li, Nainong; Zhang, Mingfeng; XUE, SHENG-LI; Cassady, Kaniel; Lin, Qing; Riggs, Arthur D; Zeng, Defu

    2015-01-01

    Induction of MHC- or HLA-matched mixed chimerism does not cause graft-versus-host disease (GVHD) in animal models or humans, but matched mixed chimerism cannot reverse autoimmunity. MHC-mismatched mixed chimerism is required for reversal of autoimmunity. Here, we report that, using a clinically applicable conditioning regimen consisting of cyclophosphamide, pentostatin, and antithymocyte globulin, MHC-mismatched mixed chimerism is established in experimental autoimmune encephalomyelitis (EAE)...

  8. 78 FR 13691 - Prospective Grant of Exclusive License: The Development of m971 and m972 Chimeric Antigen...

    Science.gov (United States)

    2013-02-28

    ... m971 and m972 Chimeric Antigen Receptors (CARs) for the Treatment of B Cell Malignancies AGENCY... inventions embodied in (a) U.S. Patent Application 61/717,960 entitled ``M971 Chimeric Antigen Receptors... their cell surface using chimeric antigen receptors which contain the m971 or m972 antibody...

  9. Identification and analysis of pig chimeric mRNAs using RNA sequencing data

    Directory of Open Access Journals (Sweden)

    Ma Lei

    2012-08-01

    Full Text Available Abstract Background Gene fusion is ubiquitous over the course of evolution. It is expected to increase the diversity and complexity of transcriptomes and proteomes through chimeric sequence segments or altered regulation. However, chimeric mRNAs in pigs remain unclear. Here we identified some chimeric mRNAs in pigs and analyzed the expression of them across individuals and breeds using RNA-sequencing data. Results The present study identified 669 putative chimeric mRNAs in pigs, of which 251 chimeric candidates were detected in a set of RNA-sequencing data. The 618 candidates had clear trans-splicing sites, 537 of which obeyed the canonical GU-AG splice rule. Only two putative pig chimera variants whose fusion junction was overlapped with that of a known human chimeric mRNA were found. A set of unique chimeric events were considered middle variances in the expression across individuals and breeds, and revealed non-significant variance between sexes. Furthermore, the genomic region of the 5′ partner gene shares a similar DNA sequence with that of the 3′ partner gene for 458 putative chimeric mRNAs. The 81 of those shared DNA sequences significantly matched the known DNA-binding motifs in the JASPAR CORE database. Four DNA motifs shared in parental genomic regions had significant similarity with known human CTCF binding sites. Conclusions The present study provided detailed information on some pig chimeric mRNAs. We proposed a model that trans-acting factors, such as CTCF, induced the spatial organisation of parental genes to the same transcriptional factory so that parental genes were coordinatively transcribed to give birth to chimeric mRNAs.

  10. Poinsettia latent virus is not a cryptic virus, but a natural polerovirus-sobemovirus hybrid.

    Science.gov (United States)

    Aus dem Siepen, Marc; Pohl, Jens O; Koo, Bong-Jin; Wege, Christina; Jeske, Holger

    2005-06-01

    The biochemical and genetic features of Poinsettia latent virus (PnLV, formerly named Poinsettia cryptic virus), which is spread worldwide in commercial cultivars of Euphorbia pulcherrima without inducing symptoms, have been determined using virus-purification, immunological techniques, electron microscopy, cloning, and sequencing. PnLV was found to be a chimeric virus with one 4652 bases, plus strand RNA showing a close relationship to poleroviruses within the first three quarters of its genome but to sobemoviruses in the last quarter. Thus, we propose to classify this virus as "polemovirus". Similarities of protein and nucleic acid sequences at the 5' and extreme 3' end of its RNA suggest a replication mode like that of poleroviruses, whereas the coat protein sequence is closely related to that of sobemoviruses. Consistent with these results, PnLV forms stable icosahedra of 34 nm in diameter. The consequences for the taxonomy of PnLV and for gardeners' practice are discussed. PMID:15892965

  11. Poinsettia latent virus is not a cryptic virus, but a natural polerovirus-sobemovirus hybrid

    International Nuclear Information System (INIS)

    The biochemical and genetic features of Poinsettia latent virus (PnLV, formerly named Poinsettia cryptic virus), which is spread worldwide in commercial cultivars of Euphorbia pulcherrima without inducing symptoms, have been determined using virus-purification, immunological techniques, electron microscopy, cloning, and sequencing. PnLV was found to be a chimeric virus with one 4652 bases, plus strand RNA showing a close relationship to poleroviruses within the first three quarters of its genome but to sobemoviruses in the last quarter. Thus, we propose to classify this virus as 'polemovirus'. Similarities of protein and nucleic acid sequences at the 5' and extreme 3' end of its RNA suggest a replication mode like that of poleroviruses, whereas the coat protein sequence is closely related to that of sobemoviruses. Consistent with these results, PnLV forms stable icosahedra of 34 nm in diameter. The consequences for the taxonomy of PnLV and for gardeners' practice are discussed

  12. Heartland Virus

    Science.gov (United States)

    ... Vector-Borne Diseases (DVBD) NCEZID Share Compartir Heartland virus On this Page What is Heartland virus? How ... Do I Need to Know? What is Heartland virus? Heartland virus belongs to a family of viruses ...

  13. Exploiting the yeast L-A viral capsid for the in vivo assembly of chimeric VLPs as platform in vaccine development and foreign protein expression.

    Directory of Open Access Journals (Sweden)

    Frank Powilleit

    Full Text Available A novel expression system based on engineered variants of the yeast (Saccharomyces cerevisiae dsRNA virus L-A was developed allowing the in vivo assembly of chimeric virus-like particles (VLPs as a unique platform for a wide range of applications. We show that polypeptides fused to the viral capsid protein Gag self-assemble into isometric VLP chimeras carrying their cargo inside the capsid, thereby not only effectively preventing proteolytic degradation in the host cell cytosol, but also allowing the expression of a per se cytotoxic protein. Carboxyterminal extension of Gag by T cell epitopes from human cytomegalovirus pp65 resulted in the formation of hybrid VLPs that strongly activated antigen-specific CD8(+ memory T cells ex vivo. Besides being a carrier for polypeptides inducing antigen-specific immune responses in vivo, VLP chimeras were also shown to be effective in the expression and purification of (i a heterologous model protein (GFP, (ii a per se toxic protein (K28 alpha-subunit, and (iii a particle-associated and fully recyclable biotechnologically relevant enzyme (esterase A. Thus, yeast viral Gag represents a unique platform for the in vivo assembly of chimeric VLPs, equally attractive and useful in vaccine development and recombinant protein production.

  14. Modeling cognition and disease using human glial chimeric mice

    DEFF Research Database (Denmark)

    Goldman, Steven A.; Nedergaard, Maiken; Windrem, Martha S.

    2015-01-01

    cognition and information processing. In addition, the cellular humanization of these brains permits their use in studying glial infectious and inflammatory disorders unique to humans, and the effects of those disorders on the glial contributions to cognition. Perhaps most intriguingly, by pairing our...... ability to construct human glial chimeras with the production of patient-specific hGPCs derived from pluripotential stem cells, we may now establish mice in which a substantial proportion of resident glia are both human and disease-derived. These mice in particular may provide us new opportunities for...... studying the human-specific contributions of glia to psychopathology, as well as to higher cognition. As such, the assessment of human glial chimeric mice may provide us new insight into the species-specific contributions of glia to human cognitive evolution, as well as to the pathogenesis of human...

  15. Chimeric Antigen Receptors Modified T-Cells for Cancer Therapy.

    Science.gov (United States)

    Dai, Hanren; Wang, Yao; Lu, Xuechun; Han, Weidong

    2016-07-01

    The genetic modification and characterization of T-cells with chimeric antigen receptors (CARs) allow functionally distinct T-cell subsets to recognize specific tumor cells. The incorporation of costimulatory molecules or cytokines can enable engineered T-cells to eliminate tumor cells. CARs are generated by fusing the antigen-binding region of a monoclonal antibody (mAb) or other ligand to membrane-spanning and intracellular-signaling domains. They have recently shown clinical benefit in patients treated with CD19-directed autologous T-cells. Recent successes suggest that the modification of T-cells with CARs could be a powerful approach for developing safe and effective cancer therapeutics. Here, we briefly review early studies, consider strategies to improve the therapeutic potential and safety, and discuss the challenges and future prospects for CAR T-cells in cancer therapy. PMID:26819347

  16. Confined Blood Chimerism in Monochorionic Dizygotic Twins Conceived Spontaneously

    Directory of Open Access Journals (Sweden)

    Takashi Kanda

    2013-05-01

    Full Text Available Traditionally, monochorionicity has been regarded as synonymous with monozygosity. However, several recent cases of monochorionic dizygotic twins have shown that monochorionic twins can be dizygous. We report a rare case of monochorionic diamnionic, gender-discordant twins who were conceived spontaneously. Initially, a monochorionic placenta was diagnosed by ultrasonography at 8 weeks of gestation and then confirmed by pathology after delivery. The twins had different genders. A comparison of cytogenetic analyses using peripheral blood lymphocytes and skin fibroblasts revealed that chimerism was confined to blood cells. We have experienced two cases of monochorionic dizygotic twins since 2003. These cases suggest that monochorionic dizygotic twins are not as rare as previously thought.

  17. Signifiance of Arginine 20 in the 2A protease for swine vesicular disease virus pathogenicity

    DEFF Research Database (Denmark)

    Inoue, Toru; Zhang, Zhidong; Wang, Leyuan; West, Laura; Bashiruddin, John B.; Belsham, Graham

    2007-01-01

    Pathogenic and attenuated strains of swine vesicular disease virus (SVDV), an enterovirus, have been characterized previously and, by using chimeric infectious cDNA clones, the key determinants of pathogenicity in pigs have been mapped to the coding region for 1D–2A. Within this region, residue 20...

  18. Systemic transport of Alfalfa mosaic virus can be mediated by the movement proteins of several viruses assigned to five genera of the 30K family.

    Science.gov (United States)

    Fajardo, Thor V M; Peiró, Ana; Pallás, Vicente; Sánchez-Navarro, Jesús

    2013-03-01

    We previously showed that the movement protein (MP) gene of Alfalfa mosaic virus (AMV) is functionally exchangeable for the cell-to-cell transport of the corresponding genes of Tobacco mosaic virus (TMV), Brome mosaic virus, Prunus necrotic ringspot virus, Cucumber mosaic virus and Cowpea mosaic virus. We have analysed the capacity of the heterologous MPs to systemically transport the corresponding chimeric AMV genome. All MPs were competent in systemic transport but required the fusion at their C terminus of the coat protein-interacting C-terminal 44 aa (A44) of the AMV MP. Except for the TMV MP, the presence of the hybrid virus in upper leaves correlated with the capacity to move locally. These results suggest that all the MPs assigned to the 30K superfamily should be exchangeable not only for local virus movement but also for systemic transport when the A44 fragment is present. PMID:23136366

  19. Highly stable expression of a foreign gene from rabies virus vectors.

    OpenAIRE

    Mebatsion, T; Schnell, M J; Cox, J H; Finke, S; Conzelmann, K K

    1996-01-01

    A reverse genetics approach was applied to generate a chimeric nonsegmented negative strand RNA virus, rabies virus (RV) of the Rhabdoviridae family, that expresses a foreign protein. DNA constructs containing the entire open reading frame of the bacterial chloramphenicol acetyltransferase (CAT) gene and an upstream RV cistron border sequence were inserted either into the nontranslated pseudogene region of a full-length cDNA copy of the RV genome or exchanged with the pseudogene region. After...

  20. Glucocorticoid regulation of mouse mammary tumor virus sequences in transgenic mice.

    OpenAIRE

    Ross, S R; Solter, D

    1985-01-01

    We have introduced a chimeric plasmid, pLTR2TK, containing the mouse mammary tumor virus (MTV) long terminal repeat (LTR) linked to the herpes simplex virus type 1 thymidine kinase gene into the mouse germ line by microinjection. In one mouse line, the thymidine kinase gene is appropriately expressed in the lactating mammary glands of heterozygous females; expression also occurs in the ovaries of these mice. In heterozygous males of this line, and in a male derived from another microinjection...

  1. Exploration of genetically encoded voltage indicators based on a chimeric voltage sensing domain

    Directory of Open Access Journals (Sweden)

    Yukiko Mishina

    2014-09-01

    We recently introduced a new VSFP design in which the voltage-sensing domain (VSD is sandwiched between a FRET pair of fluorescent proteins (termed VSFP-Butterflies and also demonstrated a series of chimeric VSD in which portions of the VSD of Ciona intestinalis voltage-sensitive phosphatase (Ci-VSP are substituted by homologous portions of a voltage-gated potassium channel subunit. These chimeric VSD had faster sensing kinetics than that of the native Ci-VSD. Here, we describe a new set of VSFPs that combine chimeric VSD with the Butterfly structure. We show that these chimeric VSFP-Butterflies can report membrane voltage oscillations of up to 200 Hz in cultured cells and report sensory evoked cortical population responses in living mice. This class of GEVIs may be suitable for imaging of brain rhythms in behaving mammalians.

  2. Quantitative chimerism kinetics in relapsed leukemia patients after allogeneic hematopoietic stem cell transplantation

    Institute of Scientific and Technical Information of China (English)

    QIN Xiao-ying; WANG Jing-zhi; ZHANG Xiao-hui; LI Jin-lan; LI Ling-di; LIU Kai-yan; HUANG Xiao-jun; LI Guo-xuan; QIN Ya-zhen; WANG Yu; WANG Feng-rong; LIU Dai-hong; XU Lan-ping; CHEN Huan; HAN Wei

    2012-01-01

    Background Chimerism analysis is an important tool for the surveillance of post-transplant engraftment.It offers the possibility of identifying impending graft rejection and recurrence of underlying malignant or non-malignant disease.Here we investigated the quantitative chimerism kinetics of 21 relapsed leukemia patients after allogeneic hematopoietic stem cell transplantation (HSCT).Methods A panel of 29 selected sequence polymorphism (SP) markers was screened by real-time polymerase chain reaction (RT-PCR) to obtain the informative marker for every leukemia patient.Quantitative chimerism analysis of bone marrow (BM) samples of 21 relapsed patients and 20 patients in stable remission was performed longitudinally.The chimerisms of BM and peripheral blood (PB) samples of 14 patients at relapse were compared.Results Twenty-one patients experienced leukemia relapse at a median of 135 days (range,30-720 days) after transplantation.High recipient chimerism in BM was found in all patients at relapse,and increased recipient chimerism in BM samples was observed in 90% (19/21) of patients before relapse.With 0.5% recipient DNA as the cut-off,median time between the detection of increased recipient chimerism and relapse was 45 days (range,0-120 days),with 76% of patients showing increased recipient chimerism at least 1 month prior to relapse.Median percentage of recipient DNA in 20 stable remission patients was 0.28%,0.04%,0.05%,0.05%,0.08%,and 0.05% at 1,2,3,6,9,and 12 months,respectively,after transplantation.This was concordant with other specific fusion transcripts and fluorescent in situ hybridization examination.The recipient chimerisms in BM were significantly higher than those in PB at relapse (P=0.001).Conclusions This SP-based RT-PCR essay is a reliable method for chimerism analysis.Chimerism kinetics in BM can be used as a marker of impending leukemia relapse,especially when no other specific marker is available.Based on our findings

  3. Assembling Single-Cell Genomes and Mini-Metagenomes From Chimeric MDA Products

    OpenAIRE

    Nurk, Sergey; Bankevich, Anton; Antipov, Dmitry; Gurevich, Alexey A.; Korobeynikov, Anton; Lapidus, Alla; Prjibelski, Andrey D.; Pyshkin, Alexey; Sirotkin, Alexander; Sirotkin, Yakov; Stepanauskas, Ramunas; Clingenpeel, Scott R.; Woyke, Tanja; Jeffrey S. McLean; Lasken, Roger

    2013-01-01

    Recent advances in single-cell genomics provide an alternative to largely gene-centric metagenomics studies, enabling whole-genome sequencing of uncultivated bacteria. However, single-cell assembly projects are challenging due to (i) the highly nonuniform read coverage and (ii) a greatly elevated number of chimeric reads and read pairs. While recently developed single-cell assemblers have addressed the former challenge, methods for assembling highly chimeric reads remain poorly explored. We p...

  4. Hematopoietic Chimerism Monitoring Based on STRs: Quantitative Platform Performance on Sequential Samples

    OpenAIRE

    Kristt, Don; Israeli, Moshe; Narinski, Ronit; Or, Hagit; Yaniv, I; Stein, Jerry; Klein, Tirza

    2005-01-01

    Hematopoietic stem cell transplantation (HSCT) creates a donor-recipient cellular chimerism in the patient, which is quantitatively assayed from peripheral blood based on STR-DNA. Since chimerism values often vary across a patient’s samples, it is important to determine to what extent this variability reflects technical aspects of platform performance. This issue is systematically assessed in the current study for the first time. Using the SGM Plus multiplex PCR kit and ABI platform, the long...

  5. Context Dependent Effects of Chimeric Peptide Morpholino Conjugates Contribute to Dystrophin Exon-skipping Efficiency

    OpenAIRE

    Yin, HaiFang; Boisguerin, Prisca; Moulton, Hong M.; Betts, Corinne; Seow, Yiqi; Boutilier, Jordan; Wang, Qingsong; Walsh, Anthony; Lebleu, Bernard; Wood, Matthew JA

    2013-01-01

    We have recently reported that cell-penetrating peptides (CPPs) and novel chimeric peptides containing CPP (referred as B peptide) and muscle-targeting peptide (referred as MSP) motifs significantly improve the systemic exon-skipping activity of morpholino phosphorodiamidate oligomers (PMOs) in dystrophin-deficient mdx mice. In the present study, the general mechanistic significance of the chimeric peptide configuration on the activity and tissue uptake of peptide conjugated PMOs in vivo was ...

  6. Targeting duplex DNA with chimeric α,β-triplex-forming oligonucleotides

    OpenAIRE

    Kolganova, N. A.; Shchyolkina, A K; Chudinov, A. V.; Zasedatelev, A S; Florentiev, V L; Timofeev, E. N.

    2012-01-01

    Triplex-directed DNA recognition is strictly limited by polypurine sequences. In an attempt to address this problem with synthetic biology tools, we designed a panel of short chimeric α,β-triplex-forming oligonucleotides (TFOs) and studied their interaction with fluorescently labelled duplex hairpins using various techniques. The hybridization of hairpin with an array of chimeric probes suggests that recognition of double-stranded DNA follows complicated rules combining reversed Hoogsteen and...

  7. Mosaic origins of a complex chimeric mitochondrial gene in Silene vulgaris.

    Directory of Open Access Journals (Sweden)

    Helena Storchova

    Full Text Available Chimeric genes are significant sources of evolutionary innovation that are normally created when portions of two or more protein coding regions fuse to form a new open reading frame. In plant mitochondria astonishingly high numbers of different novel chimeric genes have been reported, where they are generated through processes of rearrangement and recombination. Nonetheless, because most studies do not find or report nucleotide variation within the same chimeric gene, evolution after the origination of these chimeric genes remains unstudied. Here we identify two alleles of a complex chimera in Silene vulgaris that are divergent in nucleotide sequence, genomic position relative to other mitochondrial genes, and expression patterns. Structural patterns suggest a history partially influenced by gene conversion between the chimeric gene and functional copies of subunit 1 of the mitochondrial ATP synthase gene (atp1. We identified small repeat structures within the chimeras that are likely recombination sites allowing generation of the chimera. These results establish the potential for chimeric gene divergence in different plant mitochondrial lineages within the same species. This result contrasts with the absence of diversity within mitochondrial chimeras found in crop species.

  8. Prognostic Utility of Routine Chimerism Testing at 2 – 6 Months after Allogeneic Hematopoietic Cell Transplantation

    Science.gov (United States)

    Mossallam, Ghada I.; Kamel, Azza M.; Storer, Barry; Martin, Paul J.

    2009-01-01

    The utility of routine chimerism analysis as a prognostic indicator of subsequent outcomes after allogeneic hematopoietic cell transplantation (HCT) with myeloablative conditioning regimens remains controversial. To address this controversy, routine chimerism test results at 2 – 6 months after HCT with myeloablative conditioning regimens were evaluated for association with subsequent risks of chronic graft versus host disease (GVHD), non-relapse mortality (NRM), relapse and overall mortality. Only 70 (5%) of 1304 patients had <95% donor-derived cells in the marrow. Low donor chimerism in the marrow occurred predominantly among patients with low risk disease as compared to higher risk diseases and was significantly associated with a reduced risk of chronic GVHD. Among 673 patients tested, 164 (24%) had <85% donor-derived T cells in the blood. Low donor T cell chimerism occurred predominantly among patients with low risk disease as compared to higher risk diseases, among those who had conditioning with busulfan as compared to TBI, and among those with lower grades of acute GVHD. Low donor T cell chimerism in the blood was significantly associated with a reduced risk of chronic GVHD, but not with the risks of relapse, NRM or overall mortality. Routine testing of chimerism in the marrow and blood at 2 – 6 months after HCT with myeloablative conditioning regimens may be helpful in documenting engraftment in clinical trials but provides only limited prognostic information in clinical practice. PMID:19203726

  9. Targeting duplex DNA with chimeric α,β-triplex-forming oligonucleotides.

    Science.gov (United States)

    Kolganova, N A; Shchyolkina, A K; Chudinov, A V; Zasedatelev, A S; Florentiev, V L; Timofeev, E N

    2012-09-01

    Triplex-directed DNA recognition is strictly limited by polypurine sequences. In an attempt to address this problem with synthetic biology tools, we designed a panel of short chimeric α,β-triplex-forming oligonucleotides (TFOs) and studied their interaction with fluorescently labelled duplex hairpins using various techniques. The hybridization of hairpin with an array of chimeric probes suggests that recognition of double-stranded DNA follows complicated rules combining reversed Hoogsteen and non-canonical homologous hydrogen bonding. In the presence of magnesium ions, chimeric TFOs are able to form highly stable α,β-triplexes, as indicated by native gel-electrophoresis, on-array thermal denaturation and fluorescence-quenching experiments. CD spectra of chimeric triplexes exhibited features typically observed for anti-parallel purine triplexes with a GA or GT third strand. The high potential of chimeric α,β-TFOs in targeting double-stranded DNA was demonstrated in the EcoRI endonuclease protection assay. In this paper, we report, for the first time, the recognition of base pair inversions in a duplex by chimeric TFOs containing α-thymidine and α-deoxyguanosine. PMID:22641847

  10. Evaluation of the immunogenicity and protective effects of a trivalent chimeric norovirus P particle immunogen displaying influenza HA2 from subtypes H1, H3 and B

    Science.gov (United States)

    Gong, Xin; Yin, He; Shi, Yuhua; He, Xiaoqiu; Yu, Yongjiao; Guan, Shanshan; Kuai, Ziyu; Haji, Nasteha M; Haji, Nafisa M; Kong, Wei; Shan, Yaming

    2016-01-01

    The ectodomain of the influenza A virus (IAV) hemagglutinin (HA) stem is highly conserved across strains and has shown promise as a universal influenza vaccine in a mouse model. In this study, potential B-cell epitopes were found through sequence alignment and epitope prediction in a stem fragment, HA2:90-105, which is highly conserved among virus subtypes H1, H3 and B. A norovirus (NoV) P particle platform was used to express the HA2:90-105 sequences from subtypes H1, H3 and B in loops 1, 2 and 3 of the protrusion (P) domain, respectively. Through mouse immunization and microneutralization assays, the immunogenicity and protective efficacy of the chimeric NoV P particle (trivalent HA2-PP) were tested against infection with three subtypes (H1N1, H3N2 and B) of IAV in Madin–Darby canine kidney cells. The protective efficacy of the trivalent HA2-PP was also evaluated preliminarily in vivo by virus challenge in the mouse model. The trivalent HA2-PP immunogen induced significant IgG antibody responses, which could be enhanced by a virus booster vaccination. Moreover, the trivalent HA2-PP immunogen also demonstrated in vitro neutralization of the H3 and B viruses, and in vivo protection against the H3 virus. Our results support the notion that a broadly protective vaccine approach using an HA2-based NoV P particle platform can provide cross-protection against challenge viruses of different IAV subtypes. The efficacy of the immunogen should be further enhanced for practicality, and a better understanding of the protective immune mechanism will be critical for the development of HA2-based multivalent vaccines. PMID:27222326

  11. Serotype chimeric oncolytic adenovirus coding for GM-CSF for treatment of sarcoma in rodents and humans.

    Science.gov (United States)

    Bramante, Simona; Koski, Anniina; Kipar, Anja; Diaconu, Iulia; Liikanen, Ilkka; Hemminki, Otto; Vassilev, Lotta; Parviainen, Suvi; Cerullo, Vincenzo; Pesonen, Saila K; Oksanen, Minna; Heiskanen, Raita; Rouvinen-Lagerström, Noora; Merisalo-Soikkeli, Maiju; Hakonen, Tiina; Joensuu, Timo; Kanerva, Anna; Pesonen, Sari; Hemminki, Akseli

    2014-08-01

    Sarcomas are a relatively rare cancer, but often incurable at the late metastatic stage. Oncolytic immunotherapy has gained attention over the past years, and a wide range of oncolytic viruses have been delivered via intratumoral injection with positive safety and promising efficacy data. Here, we report preclinical and clinical results from treatment of sarcoma with oncolytic adenovirus Ad5/3-D24-GMCSF (CGTG-102). Ad5/3-D24-GMCSF is a serotype chimeric oncolytic adenovirus coding for human granulocyte-macrophage colony-stimulating factor (GM-CSF). The efficacy of Ad5/3-D24-GMCSF was evaluated on a panel of soft-tissue sarcoma (STS) cell lines and in two animal models. Sarcoma specific human data were also collected from the Advanced Therapy Access Program (ATAP), in preparation for further clinical development. Efficacy was seen in both in vitro and in vivo STS models. Fifteen patients with treatment-refractory STS (13/15) or primary bone sarcoma (2/15) were treated in ATAP, and treatments appeared safe and well-tolerated. A total of 12 radiological RECIST response evaluations were performed, and two cases of minor response, six cases of stable disease and four cases of progressive disease were detected in patients progressing prior to virus treatment. Overall, the median survival time post treatment was 170 days. One patient is still alive at 1,459 days post virus treatment. In summary, Ad5/3-D24-GMCSF appears promising for the treatment of advanced STS; a clinical trial for treatment of refractory injectable solid tumors including STS is ongoing. PMID:24374597

  12. Toxicities of chimeric antigen receptor T cells: recognition and management.

    Science.gov (United States)

    Brudno, Jennifer N; Kochenderfer, James N

    2016-06-30

    Chimeric antigen receptor (CAR) T cells can produce durable remissions in hematologic malignancies that are not responsive to standard therapies. Yet the use of CAR T cells is limited by potentially severe toxicities. Early case reports of unexpected organ damage and deaths following CAR T-cell therapy first highlighted the possible dangers of this new treatment. CAR T cells can potentially damage normal tissues by specifically targeting a tumor-associated antigen that is also expressed on those tissues. Cytokine release syndrome (CRS), a systemic inflammatory response caused by cytokines released by infused CAR T cells can lead to widespread reversible organ dysfunction. CRS is the most common type of toxicity caused by CAR T cells. Neurologic toxicity due to CAR T cells might in some cases have a different pathophysiology than CRS and requires different management. Aggressive supportive care is necessary for all patients experiencing CAR T-cell toxicities, with early intervention for hypotension and treatment of concurrent infections being essential. Interleukin-6 receptor blockade with tocilizumab remains the mainstay pharmacologic therapy for CRS, though indications for administration vary among centers. Corticosteroids should be reserved for neurologic toxicities and CRS not responsive to tocilizumab. Pharmacologic management is complicated by the risk of immunosuppressive therapy abrogating the antimalignancy activity of the CAR T cells. This review describes the toxicities caused by CAR T cells and reviews the published approaches used to manage toxicities. We present guidelines for treating patients experiencing CRS and other adverse events following CAR T-cell therapy. PMID:27207799

  13. Dosimetry of chimeric TNT in lung tumor patients

    Institute of Scientific and Technical Information of China (English)

    CHEN Yangchun; CHEN Shaoliang; JU Dianwen; SHI Hongcheng; YAO Zhifeng

    2007-01-01

    The purpose of this study was to assess the absorbed dose of tumor and main critical organs in 131I labeled chimeric tumor necrotic treatment (chTNT). In 9 patients, a single intravenous dose of (29.6±3.7) MBq/kg was administered. Blood samples were drawn at different time intervals, and urine was collected for up to one week. Tissue distribution of 131I -chTNT was followed for up to one week by gamma camera imaging. Absorbed doses to the whole body and to normal organs were computed according to the MIRD scheme using Mirdose-3 software. S-factors for lung tumors were estimated by comparison with lungs of similar mass and position in the body. It was found that mean serum disappearance half time values for 131I-chTNT were (4.93±9.36) h and (61.7±21.2) h for α, β respectively,while that for whole body was(99±10) h. Mean urine biological clearance half time value was (90±10) h. The absorbed dose to tumor was (8.28±2.65) Gy, and the tumor-to-nontumor dose ratio was 3.95±1.55. And the mean effective dose to patients was (1.02±0.29) mSv/MBq.

  14. Development of chimeric antigen receptors for multiple myeloma.

    Science.gov (United States)

    Martínez-Cingolani, Carolina; Bories, Jean Christophe

    2016-04-15

    Multiple myeloma (MM) is a haematologic malignancy characterized by the expansion of monoclonal plasma cells in the bone marrow. It is associated with serum or urine monoclonal protein and organ damage including renal failure, anaemia, hypercalcaemia and bone lesions. Despite recent improvements MM still remains an incurable disease. Previous studies have shown that the adoptive transfer of autologous T-cells modified to express chimeric antigen receptors (CAR) is effective in cases of acute and chronic lymphoid leukaemia. However, the adjustment of CAR-T-cell therapy to MM is hindered by the scarcity of antigens specific to the tumour plasma cells. Most candidate targets are shared by healthy tissues, and entail high risks of toxicity. Therefore several strategies have been proposed to regulate CAR-T-cell function as well as to enhance CAR-T-cell specificity against tumour cells. In this article we summarize the surface markers that have been investigated as targets to eliminate MM plasma cells and the MM-specific CARs that have been developed to date. Then we describe the different CAR-T-cell designs that could be applied in the case of MM to circumvent current problems of toxicity. PMID:27068946

  15. Dosimetry of chimeric TNT in lung tumor patients

    International Nuclear Information System (INIS)

    The purpose of this study was to assess the absorbed dose of tumor and main critical organs in 131I labeled chimeric tumor necrotic treatment (chTNT). In 9 patients, a single intravenous dose of (29.6±3.7) MBq/kg was administered. Blood samples were drawn at different time intervals, and urine was collected for up to one week. Tissue distribution of 131I -chTNT was followed for up to one week by gamma camera imaging. Absorbed doses to the whole body and to normal organs were computed according to the MIRD scheme using Mirdose-3 software. S-factors for lung tumors were estimated by comparison with lungs of similar mass and position in the body. It was found that mean serum disappearance half time values for 131I-chTNT were (4.934±9.36) h and (61.74±21.2) h for α, β respectively, while that for whole body was(99±10) h. Mean urine biological clearance half time value was (90±10) h. The ab- sorbed dose to tumor was (8.28±2.65) Gy, and the tumor-to-nontumor dose ratio was 3.95±1.55. And the mean effective dose to patients was (1.02±0.29) mSv/MBq. (authors)

  16. The virus-associated human immunodeficiency virus type 1 Gag-Pol carrying an active protease domain in the matrix region is severely defective both in autoprocessing and in trans processing of gag particles

    International Nuclear Information System (INIS)

    We have previously demonstrated that a human immunodeficiency virus (HIV) chimeric Gag protein containing a partial replacement of the matrix domain by the viral protease domain (PR) could undergo autoprocessing with no virus particle production [J. Virol. 74 (2000) 3418]. To further analyze the effects of repositioned PR on virus particle production and Gag-Pol incorporation, we introduced the chimeric PR construct into a PR-negative Gag-Pol expression plasmid and coexpressed the resultant construct with a Pr55gag expression plasmid (pGAG) in 293T cells. Analysis indicated that the chimeric PR was similar to native PR in that both could prevent virus particle production in cotransfections with an equivalent amount of pGAG plasmid DNA, suggesting an efficient trans processing of Pr55gag by the chimeric PR. In cotransfections with the pGAG at a DNA ratio of 1:10 to 1:20, which resembles the normal intracellular expression ratio of Gag-Pol to Gag, Gag-Pol carrying the PR in the Gag coding region could undergo autoprocessing in cells and was incorporated into virus particles at a level about 20-40% of that of wild-type Gag-Pol. However, the incorporated chimeric Gag-Pol was unable to autocleave and unable to process the Gag particles properly, as mature particle-associated reverse transcriptase (RT) and p24gag proteins were barely detected. Our data strongly suggest that positioning an active HIV PR in the matrix region significantly affects the PR-mediated virus particle maturation

  17. Immunological tolerance and tumor rejection in embryo-aggregated chimeric mice – Lessons for tumor immunity

    International Nuclear Information System (INIS)

    Rejection of transplanted tumors by the immune system is a rare event in syngeneic hosts, and is considered to be dependent on the local interaction of defensive immune reactions and tumor tolerance mechanisms. Here, we have enlisted the aid of a unique set of embryo-aggregated lineage chimeric mice derived from C57/BL6 and FVB donors to study the interplay between local and systemic tumor immunity and tolerance in rejection of mouse B16 melanoma cells, syngeneic to the C57/BL6 donor strain. Two variants of embryo-aggregated chimeric mice with either variable or no contribution of C57-derived cells to their skin were generated by the fusion of different ratios of morula stage blastomers. Chimeric mice were analyzed for s.c. growth of B16 tumors in comparison to their respective donor strains as well as normal F1 hybrids, and the relative frequencies of cellular components of the immune system by FACS analysis of peripheral blood or lymph node cells. B16 tumors grew significantly faster in mice with full chimerism in their skin as compared to syngeneic C57 or semi-syngeneic C57 × FVB F1 hosts. In contrast, s.c. tumor growth was either absent or significantly reduced in chimeric mice lacking C57-derived cells in their skin, but tolerant to C57 tissue in other organs. Comparison of the relative frequencies of various immune cells in the periphery via FACS-analysis did not reveal any significant differences between the two types of chimeric mice with respect to their donor strains. Our data suggest a complex interplay between mechanisms of local peripheral tolerance and innate antitumor mechanisms possibly involving NK cell allorecognition as a basis for the differential growth or rejection of B16 tumors in these unique chimeric mice, which we suggest to constitute a valuable new model system for the study of immune-mediated tumor rejection

  18. Antigenic properties of a transport-competent influenza HA/HIV Env chimeric protein

    International Nuclear Information System (INIS)

    The transmembrane subunit (gp41) of the HIV Env glycoprotein contains conserved neutralizing epitopes which are not well-exposed in wild-type HIV Env proteins. To enhance the exposure of these epitopes, a chimeric protein, HA/gp41, in which the gp41 of HIV-1 89.6 envelope protein was fused to the C-terminus of the HA1 subunit of the influenza HA protein, was constructed. Characterization of protein expression showed that the HA/gp41 chimeric proteins were expressed on cell surfaces and formed trimeric oligomers, as found in the HIV Env as well as influenza HA proteins. In addition, the HA/gp41 chimeric protein expressed on the cell surface can also be cleaved into 2 subunits by trypsin treatment, similar to the influenza HA. Moreover, the HA/gp41 chimeric protein was found to maintain a pre-fusion conformation. Interestingly, the HA/gp41 chimeric proteins on cell surfaces exhibited increased reactivity to monoclonal antibodies against the HIV Env gp41 subunit compared with the HIV-1 envelope protein, including the two broadly neutralizing monoclonal antibodies 2F5 and 4E10. Immunization of mice with a DNA vaccine expressing the HA/gp41 chimeric protein induced antibodies against the HIV gp41 protein and these antibodies exhibit neutralizing activity against infection by an HIV SF162 pseudovirus. These results demonstrate that the construction of such chimeric proteins can provide enhanced exposure of conserved epitopes in the HIV Env gp41 and may represent a novel vaccine design strategy for inducing broadly neutralizing antibodies against HIV

  19. Immune Reconstitution Kinetics following Intentionally Induced Mixed Chimerism by Nonmyeloablative Transplantation.

    Directory of Open Access Journals (Sweden)

    Nayoun Kim

    Full Text Available Establishing mixed chimerism is a promising approach for inducing donor-specific transplant tolerance. The establishment and maintenance of mixed chimerism may enable long-term engraftment of organ transplants while minimizing the use of immunosuppressants. Several protocols for inducing mixed chimerism have been reported; however, the exact mechanism underlying the development of immune tolerance remains to be elucidated. Therefore, understanding the kinetics of engraftment during early post-transplant period may provide insight into establishing long-term mixed chimerism and permanent transplant tolerance. In this study, we intentionally induced allogeneic mixed chimerism using a nonmyeloablative regimen by host natural killer (NK cell depletion and T cell-depleted bone marrow (BM grafts in a major histocompatibility complex (MHC-mismatched murine model and analyzed the kinetics of donor (C57BL/6 and recipient (BALB/c engraftment in the weeks following transplantation. Donor BM cells were well engrafted and stabilized without graft-versus-host disease (GVHD as early as one week post-bone marrow transplantation (BMT. Donor-derived thymic T cells were reconstituted four weeks after BMT; however, the emergence of newly developed T cells was more obvious at the periphery as early as two weeks after BMT. Also, the emergence and changes in ratio of recipient- and donor-derived NKT cells and antigen presenting cells (APCs including dendritic cells (DCs and B cells were noted after BMT. Here, we report a longitudinal analysis of the development of donor- and recipient-originated hematopoietic cells in various lymphatic tissues of intentionally induced mixed chimerism mouse model during early post-transplant period. Through the understanding of immune reconstitution at early time points after nonmyeloablative BMT, we suggest guidelines on intentionally inducing durable mixed chimerism.

  20. Envelope gene sequences encoding variable regions 3 and 4 are involved in macrophage tropism of feline immunodeficiency virus

    NARCIS (Netherlands)

    Horzinek, M.C.; Vahlenkamp, T.W.; Ronde, A. de; Schuurman, N.M.P.; Vliet, A.L.W. van; Drunen, J. van; Egberink, H.F.

    1999-01-01

    The envelope is of cardinal importance for the entry of feline immunodeficiency virus (FIV) into its host cells, which consist of cells of the immune system including macrophages. To characterize the envelope glycoprotein determinants involved in macrophage tropism, chimeric infectious molecular clo

  1. Generation of transgenic watermelon resistant to Zucchini yellow mosaic virus and Papaya ringspot virus type W.

    Science.gov (United States)

    Yu, Tsong-Ann; Chiang, Chu-Hui; Wu, Hui-Wen; Li, Chin-Mei; Yang, Ching-Fu; Chen, Jun-Han; Chen, Yu-Wen; Yeh, Shyi-Dong

    2011-03-01

    Zucchini yellow mosaic virus (ZYMV) and Papaya ringspot virus type W (PRSV W) are major limiting factors for production of watermelon worldwide. For the effective control of these two viruses by transgenic resistance, an untranslatable chimeric construct containing truncated ZYMV coat protein (CP) and PRSV W CP genes was transferred to commercial watermelon cultivars by Agrobacterium-mediated transformation. Using our protocol, a total of 27 putative transgenic lines were obtained from three cultivars of 'Feeling' (23 lines), 'China baby' (3 lines), and 'Quality' (1 line). PCR and Southern blot analyses confirmed that the chimeric construct was incorporated into the genomic DNA of the transformants. Greenhouse evaluation of the selected ten transgenic lines of 'Feeling' cultivar revealed that two immune lines conferred complete resistance to ZYMV and PRSV W, from which virus accumulation were not detected by Western blotting 4 weeks after inoculation. The transgenic transcript was not detected, but small interfering RNA (siRNA) was readily detected from the two immune lines and T(1) progeny of line ZW 10 before inoculation, indicating that RNA-mediated post-transcriptional gene silencing (PTGS) is the underlying mechanism for the double-virus resistance. The segregation ratio of T(1) progeny of the immune line ZW10 indicated that the single inserted transgene is nuclearly inherited and associated with the phenotype of double-virus resistance as a dominant trait. The transgenic lines derived from the commercial watermelon cultivars have great potential for control of the two important viruses and can be implemented directly without further breeding. PMID:21079966

  2. Overexpression of the Synthetic Chimeric Native-T-phylloplanin-GFP Genes Optimized for Monocot and Dicot Plants Renders Enhanced Resistance to Blue Mold Disease in Tobacco (N. tabacum L.

    Directory of Open Access Journals (Sweden)

    Dipak K. Sahoo

    2014-01-01

    Full Text Available To enhance the natural plant resistance and to evaluate the antimicrobial properties of phylloplanin against blue mold, we have expressed a synthetic chimeric native-phylloplanin-GFP protein fusion in transgenic Nicotiana tabacum cv. KY14, a cultivar that is highly susceptible to infection by Peronospora tabacina. The coding sequence of the tobacco phylloplanin gene along with its native signal peptide was fused with GFP at the carboxy terminus. The synthetic chimeric gene (native-phylloplanin-GFP was placed between the modified Mirabilis mosaic virus full-length transcript promoter with duplicated enhancer domains and the terminator sequence from the rbcSE9 gene. The chimeric gene, expressed in transgenic tobacco, was stably inherited in successive plant generations as shown by molecular characterization, GFP quantification, and confocal fluorescent microscopy. Transgenic plants were morphologically similar to wild-type plants and showed no deleterious effects due to transgene expression. Blue mold-sensitivity assays of tobacco lines were performed by applying P. tabacina sporangia to the upper leaf surface. Transgenic lines expressing the fused synthetic native-phyllopanin-GFP gene in the leaf apoplast showed resistance to infection. Our results demonstrate that in vivo expression of a synthetic fused native-phylloplanin-GFP gene in plants can potentially achieve natural protection against microbial plant pathogens, including P. tabacina in tobacco.

  3. Overexpression of the synthetic chimeric native-T-phylloplanin-GFP genes optimized for monocot and dicot plants renders enhanced resistance to blue mold disease in tobacco (N. tabacum L.).

    Science.gov (United States)

    Sahoo, Dipak K; Raha, Sumita; Hall, James T; Maiti, Indu B

    2014-01-01

    To enhance the natural plant resistance and to evaluate the antimicrobial properties of phylloplanin against blue mold, we have expressed a synthetic chimeric native-phylloplanin-GFP protein fusion in transgenic Nicotiana tabacum cv. KY14, a cultivar that is highly susceptible to infection by Peronospora tabacina. The coding sequence of the tobacco phylloplanin gene along with its native signal peptide was fused with GFP at the carboxy terminus. The synthetic chimeric gene (native-phylloplanin-GFP) was placed between the modified Mirabilis mosaic virus full-length transcript promoter with duplicated enhancer domains and the terminator sequence from the rbcSE9 gene. The chimeric gene, expressed in transgenic tobacco, was stably inherited in successive plant generations as shown by molecular characterization, GFP quantification, and confocal fluorescent microscopy. Transgenic plants were morphologically similar to wild-type plants and showed no deleterious effects due to transgene expression. Blue mold-sensitivity assays of tobacco lines were performed by applying P. tabacina sporangia to the upper leaf surface. Transgenic lines expressing the fused synthetic native-phyllopanin-GFP gene in the leaf apoplast showed resistance to infection. Our results demonstrate that in vivo expression of a synthetic fused native-phylloplanin-GFP gene in plants can potentially achieve natural protection against microbial plant pathogens, including P. tabacina in tobacco. PMID:24778589

  4. Recombinant hybrid infectious hematopoietic necrosis virus (IHNV) carrying viral haemorrhagic septicaemia virus (VHSV) G or NV genes show different virulence properities

    DEFF Research Database (Denmark)

    Einer-Jensen, Katja; Biacchesi, S.; Stegmann, Anders; Bremont, M.; Lorenzen, Niels

    importance. By a reverse genetics approach using the related novirrhabdovirus infectious hematopoietic necrosis virus (IHNV) as basis, four hybrid IHNV-VHSV variants were generated. These chimeric variants included substitution of the IHNV glyco(G) or nonstrutrual (Nv) protein with the corresponding G or Nv......-protein from either a freshwater or a marine VHSV strain. Following rescue of the hybrid viruses, comparative challenge experiments in rainbow trout fingerlings have been performed. The pathogenicity of the recombinant IHNV-VHSV hybrid viruses were similar, regardless of whether the G or Nv originate from...

  5. Endosymbiotic gene transfer from prokaryotic pangenomes: Inherited chimerism in eukaryotes.

    Science.gov (United States)

    Ku, Chuan; Nelson-Sathi, Shijulal; Roettger, Mayo; Garg, Sriram; Hazkani-Covo, Einat; Martin, William F

    2015-08-18

    Endosymbiotic theory in eukaryotic-cell evolution rests upon a foundation of three cornerstone partners--the plastid (a cyanobacterium), the mitochondrion (a proteobacterium), and its host (an archaeon)--and carries a corollary that, over time, the majority of genes once present in the organelle genomes were relinquished to the chromosomes of the host (endosymbiotic gene transfer). However, notwithstanding eukaryote-specific gene inventions, single-gene phylogenies have never traced eukaryotic genes to three single prokaryotic sources, an issue that hinges crucially upon factors influencing phylogenetic inference. In the age of genomes, single-gene trees, once used to test the predictions of endosymbiotic theory, now spawn new theories that stand to eventually replace endosymbiotic theory with descriptive, gene tree-based variants featuring supernumerary symbionts: prokaryotic partners distinct from the cornerstone trio and whose existence is inferred solely from single-gene trees. We reason that the endosymbiotic ancestors of mitochondria and chloroplasts brought into the eukaryotic--and plant and algal--lineage a genome-sized sample of genes from the proteobacterial and cyanobacterial pangenomes of their respective day and that, even if molecular phylogeny were artifact-free, sampling prokaryotic pangenomes through endosymbiotic gene transfer would lead to inherited chimerism. Recombination in prokaryotes (transduction, conjugation, transformation) differs from recombination in eukaryotes (sex). Prokaryotic recombination leads to pangenomes, and eukaryotic recombination leads to vertical inheritance. Viewed from the perspective of endosymbiotic theory, the critical transition at the eukaryote origin that allowed escape from Muller's ratchet--the origin of eukaryotic recombination, or sex--might have required surprisingly little evolutionary innovation. PMID:25733873

  6. Chimeric mouse-human IgG1 antibody that can mediate lysis of cancer cells

    International Nuclear Information System (INIS)

    A chimeric mouse-human antibody has been created that recognizes an antigen found on the surface of cells from many carcinomas. Immunoglobulin constant (C) domains of the mouse monoclonal antibody L6, C/sub γ2a/ and C/sub kappa/, were substituted by the human C/sub γ1/ and C/sub kappa/ by recombining cDNA modules encoding variable or C domains. The cDNA constructs were transfected into lymphoid cells for antibody production. The chimeric antibody and mouse L6 antibody bound to carcinoma cells with equal affinity and mediated complement-dependent cytolysis. In the presence of human effector cells, the chimeric antibody gave antibody-dependent cellular cytotoxicity at 100 times lower concentration than that needed for the mouse L6 antibody. The assay for lysis was carried out with 51Cr-labeled target calls. The chimeric antibody, but not the mouse L6 antibody, is effective against a melanoma line expressing small amounts of the L6 antigen. The findings point to the usefulness of the chimeric antibody approach for obtaining agents with strong antitumor activity for possible therapeutic use in man

  7. Recognition of base pair inversions in duplex by chimeric (alpha,beta) triplex-forming oligonucleotides.

    Science.gov (United States)

    Timofeev, Edward N; Goryaeva, Baira V; Florentiev, Vladimir L

    2006-10-01

    DNA recognition by triplex-forming oligonucleotides (TFOs) is usually limited by homopurine-homopyrimidine sequence in duplexes. Modifications of the third strand may overcome this limitation. Chimeric alpha-beta TFOs are expected to form triplex DNA upon binding to non-regular sequence duplexes. In the present study we describe binding properties of chimeric alpha-beta oligodeoxynucleotides in the respect to short DNA duplexes with one, three, and five base pair inversions. Non-natural chimeric TFO's contained alpha-thymidine residues inside (GT) or (GA) core sequences. Modified residues were addressed to AT/TA inversions in duplexes. It was found in the non-denaturing gel-electrophoresis experiments that single or five adjacent base pair inversions in duplexes may be recognized by chimeric alpha-beta TFO's at 10 degrees C and pH 7.8. Three dispersed base pair inversions in the double stranded DNA prevented triplex formation by either (GT) or (GA) chimeras. Estimation of thermal stability of chimeric alpha-beta triplexes showed decrease in T(m) values as compared with unmodified complexes. PMID:16928141

  8. Chimeric spider silk proteins mediated by intein result in artificial hybrid silks.

    Science.gov (United States)

    Lin, Senzhu; Chen, Gefei; Liu, Xiangqin; Meng, Qing

    2016-07-01

    Hybrid silks hold a great potential as specific biomaterials due to its controlled mechanical properties. To produce fibers with tunable properties, here we firstly made chimeric proteins in vitro, called W2C4CT and W2C8CT, with ligation of MaSp repetitive modules (C) with AcSp modules (W) by intein trans splicing technology from smaller precursors without final yield reduction. Intein mediated chimeric proteins form fibers at a low concentration of 0.4 mg/mL in 50 mM K3 PO4 pH 7.5 just drawn by hand. Hybrid fibers show smoother surface, and also have stronger chemical resistance as compared with fibers from W2CT (W fibers) and mixture of W2CT/C8CT (MHF8 fibers). Fibers from chimeric protein W2C4CT (HFH4) have improved mechanical properties than W fibers; however, with more C modules W2C8CT fibers (HFH8) properties decreased, indicates the length proportion of various modules is very important and should be optimized for fibers with specific properties. Generally, hybrid silks generated via chimeric proteins, which can be simplified by intein trans splicing, has greater potential to produce fibers with tunable properties. Our research shows that intein mediated directional protein ligation is a novel way to make large chimeric spider silk proteins and hybrid silks. © 2016 Wiley Periodicals, Inc. Biopolymers 105: 385-392, 2016. PMID:26948769

  9. Off-label use of maraviroc in HIV-1-infected paediatric patients in clinical practice.

    Science.gov (United States)

    Palladino, Claudia; Gómez, María Luisa Navarro; Soler-Palacín, Pere; González-Tomé, María Isabel; De Ory, Santiago J; Espiau, María; Hoyos, Santiago Pérez; León-Leal, Juan Antonio; Méndez, María; Moreno-Pérez, David; Guasch, Claudia Fortuny; Sierra, Antoni Mur; Guruceta, Itziar Pocheville; Guillén, Santiago Moreno; Briz, Verónica

    2015-10-23

    Maraviroc (MVC) is not approved for HIV-1-infected paediatric patients. This is the first assessment of the use of MVC-based salvage therapy in vertically HIV-1-infected paediatric patients in clinical settings. The results suggest that MVC-based salvage therapy is useful in children and adolescents with extensive resistance profile leading to maintained virological suppression in up to 88% of the patients with CCR5-tropic virus. The likelihood of treatment success might increase when MVC is combined with other active drugs. PMID:26544580

  10. SHIV-1157i and passaged progeny viruses encoding R5 HIV-1 clade C env cause AIDS in rhesus monkeys

    OpenAIRE

    Siddappa Nagadenahalli B; Kramer Victor G; Chenine Agnès L; Sharma Prachi; Ong Helena; Song Ruijiang; Rasmussen Robert A; Humbert Michael; Xu Weidong; Else James G; Novembre Francis J; Strobert Elizabeth; O'Neil Shawn P; Ruprecht Ruth M

    2008-01-01

    Abstract Background Infection of nonhuman primates with simian immunodeficiency virus (SIV) or chimeric simian-human immunodeficiency virus (SHIV) strains is widely used to study lentiviral pathogenesis, antiviral immunity and the efficacy of AIDS vaccine candidates. SHIV challenges allow assessment of anti-HIV-1 envelope responses in primates. As such, SHIVs should mimic natural HIV-1 infection in humans and, to address the pandemic, encode HIV-1 Env components representing major viral subty...

  11. ECHO virus

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/001340.htm ECHO virus To use the sharing features on this page, please enable JavaScript. Enteric cytopathic human orphan (ECHO) viruses are a group of viruses that lead to ...

  12. Targeted transcriptional repression using a chimeric TALE-SRDX repressor protein

    KAUST Repository

    Mahfouz, Magdy M.

    2011-12-14

    Transcriptional activator-like effectors (TALEs) are proteins secreted by Xanthomonas bacteria when they infect plants. TALEs contain a modular DNA binding domain that can be easily engineered to bind any sequence of interest, and have been used to provide user-selected DNA-binding modules to generate chimeric nucleases and transcriptional activators in mammalian cells and plants. Here we report the use of TALEs to generate chimeric sequence-specific transcriptional repressors. The dHax3 TALE was used as a scaffold to provide a DNA-binding module fused to the EAR-repression domain (SRDX) to generate a chimeric repressor that targets the RD29A promoter. The dHax3. SRDX protein efficiently repressed the transcription of the RD29A

  13. The determination of lymphoid cell chimerism using peripheral blood lymphocytes from murine bone marrow chimeras

    International Nuclear Information System (INIS)

    A simple, rapid and accurate method was devised for determining lymphoid cell chimerism in bone marrow-reconstituted mice. Chimeras were produced by reconstituting lethally irradiated mice with semi-allogeneic bone marrow cells. Lymphocytes from the peripheral blood of individual chimeric mice were purified by sedimentation in dextran solution and differential flotation in Ficoll-Hypaque gradients. From 250-500 μl of blood, 1-7 x 105 cells were routinely obtained. The extent of chimerism was determined serologically by using peripheral blood lymphocytes as target cells in a dye exclusion microcytotoxicity assay. Using this new technique, approximately 80% of the reconstituted mice were found to be repopulated with lymphocytes of the donor type. (Auth.)

  14. Chimerism a natural ability to tolerate kin, evolutionary traits connecting mammalian and protochordates

    Directory of Open Access Journals (Sweden)

    A Voskoboynik

    2009-03-01

    Full Text Available In the middle of the 20th century, Owen (1945, 1954 and Billingham et al. (1953 immunological studies suggested that fetal exposure to foreign antigens during pregnancy induce immunologic tolerance in the fetus. Recently, Mold et al. found that a substantial number of maternal cells crosses the placenta to reside in fetal lymph nodes and induces the development of regulatory T cells (Tregs that suppress fetal anti-maternal immunity. These Tregs cells persist till, at least, early adulthood. This result demonstrates how chimerism induces fetal tolerance to maternal antigens during mammalian pregnancy. Natural chimerism is the coexistence of two or more genomic lineages within the same individual. It is a common phenomenon which can be detected in a wide variety of multi-cellular organisms. In mammals, natural chimerism can be established during pregnancy between the mother and the fetus or between fetuses in a multiple embryos pregnancy. Restriction of natural chimerism mainly to kin is also observed in colonial marine protochordates. In protochordates, like Botryllus schlosseri, natural chimerism can be established through fusion of vasculature, between a parent colony and its progeny or between siblings (adult distinct colonies.The ability to tolerate a partial allogeneic individual and to create a chimeric entity between these colonies is determined by a single, highly polymorphic, fusion/histocompatibility locus (Fu/HC. Colonies that share at least one allele in their Fu/HC locus would fuse upon contact. A pair that does not share any Fu/HC allele would not. In the chimera, cells transmigrate between partners and in some cases, replace the germline and/or the somatic tissues of the host. This genotype replacement is mediated by stem cells (termed somatic/germ cell parasitism. Botryllus colonies propagate asexually through budding, therefore somatic stem cell parasitism in host colonies can induce the development of a partial allogeneic entity

  15. Interspecies chimeric complementation for the generation of functional human tissues and organs in large animal hosts.

    Science.gov (United States)

    Wu, Jun; Izpisua Belmonte, Juan Carlos

    2016-06-01

    The past decade's rapid progress in human pluripotent stem cell (hPSC) research has generated hope for meeting the rising demand of organ donation, which remains the only effective cure for end-stage organ failure, a major cause of death worldwide. Despite the potential, generation of transplantable organs from hPSCs using in vitro differentiation is far-fetched. An in vivo interspecies chimeric complementation strategy relying on chimeric-competent hPSCs and zygote genome editing provides an auspicious alternative for providing unlimited organ source for transplantation. PMID:26820411

  16. Molecular chimerization of Pasteurella haemolytica leukotoxin to interleukin-2: effects on cytokine and antigen function.

    OpenAIRE

    Hughes, H P; Campos, M.; Potter, A A; Babiuk, L. A.

    1992-01-01

    A chimeric recombinant protein composed of the lktA gene product from Pasteurella haemolytica fused to bovine interleukin-2 (IL-2) was made. The LKT-IL-2 chimera was compared with recombinant bovine IL-2 with regard to the ability to induce proliferative responses and LAK cell activity in bovine peripheral blood mononuclear cells in vitro. In both instances, chimerization had no effect on IL-2 activity. Similarly, the LKT component was unaffected in its ability to induce an effective immune r...

  17. Dosimetry of chimeric TNT in lung cancer patients

    International Nuclear Information System (INIS)

    Objective: To assess the irradiated absorptive dose of tumor and main critical organs chimeric tumor necrotic treatment (chTNT). Methods: In 9 lung cancer patients a single intravenous dose of 131I-chTNT (29.6±3.7) MBq/kg was administered. Blood samples were drawn at different time intervals and urine was collected for up to one week. Tissue distribution was followed for up to one week by gamma camera imaging. The geometric mean of the anterior and posterior counts was obtained from selected regions of interest (ROIs) to determine activity within the critical organs after being subtracted the background activity. Counts from thyroid were obtained from anterior images only. A background region was drawn below the thyroid gland to subtract underlying activity in the neck blood vessels. The geometric mean of the counts in the whole body scintigram at 0.5 h after injection was corrected for radioactive decay from the time of injection , this value being taken as 100%ID. The residence times for each critical organ and the remainder of the body were computed by dividing the area under their %ID/h curves by the 100%ID value. Absorbed doses to the whole body and to normal organ were computed from the residence time according to the MIRD scheme using Mirdose-3 software. Absorbed doses to tumor tissues were estimated using the same approach taken for normal organs. S-factors for tumors were estimated by comparison with normal organs of similar mass and position in the body. Results: Mean serum disappearance half time values for 131I-chTNT were α (4.9 ± 9.4) h, β (61.7 ± 21.2) h; and whole body, (99 ± 10) h. Mean urine biological clearance half time values was (90 ± 10) h. The absorbed dose of tumor was (8.28 ± 2.65) Gy, the tumor-to-nontumor ratio was 3.95 ± 1.55, while the absorbed dose of marrow was 0.44-0.73 Gy, thyroid was 0.47-23.09 Gy, ovaries was 0.50-0.77 Gy, testicles was 0.38-0.58 Gy, kidneys was 1.71- 4.55 Gy, liver was 1.18-2.63 Gy, and lungs was 1

  18. In vivo evaluation of the cross-genotype neutralizing activity of polyclonal antibodies against hepatitis C virus

    DEFF Research Database (Denmark)

    Meuleman, Philip; Bukh, Jens; Verhoye, Lieven;

    2011-01-01

    1977 (H77). In this study we investigated whether polyclonal antibodies isolated from Patient H in 2006 (H06), which display high cross-genotype neutralizing activity in both the HCV pseudoparticle (HCVpp) and HCV cell culture (HCVcc) systems, were also able to prevent HCV infection of different...... genotypes (gt) in vivo. Following passive immunization with H06-antibodies, chimeric mice were challenged with the consensus strains H77C (gt1a), ED43 (gt4a), or HK6a (gt6a). In accordance with previous results, H06-antibodies prevented infection of chimeric mice with the autologous virus. However, the...

  19. Treatment of melanoma with a serotype 5/3 chimeric oncolytic adenovirus coding for GM-CSF: Results in vitro, in rodents and in humans.

    Science.gov (United States)

    Bramante, Simona; Kaufmann, Johanna K; Veckman, Ville; Liikanen, Ilkka; Nettelbeck, Dirk M; Hemminki, Otto; Vassilev, Lotta; Cerullo, Vincenzo; Oksanen, Minna; Heiskanen, Raita; Joensuu, Timo; Kanerva, Anna; Pesonen, Sari; Matikainen, Sampsa; Vähä-Koskela, Markus; Koski, Anniina; Hemminki, Akseli

    2015-10-01

    Metastatic melanoma is refractory to irradiation and chemotherapy, but amenable to immunological approaches such as immune-checkpoint-inhibiting antibodies or adoptive cell therapies. Oncolytic virus replication is an immunogenic phenomenon, and viruses can be armed with immunostimulatory molecules. Therefore, oncolytic immuno-virotherapy of malignant melanoma is an appealing approach, which was recently validated by a positive phase 3 trial. We investigated the potency of oncolytic adenovirus Ad5/3-D24-GMCSF on a panel of melanoma cell lines and animal models, and summarized the melanoma-specific human data from the Advanced Therapy Access Program (ATAP). The virus effectively eradicated human melanoma cells in vitro and subcutaneous SK-MEL-28 melanoma xenografts in nude mice when combined with low-dose cyclophosphamide. Furthermore, virally-expressed granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulated the differentiation of human monocytes into macrophages. In contrast to human cells, RPMI 1846 hamster melanoma cells exhibited no response to oncolytic viruses and the chimeric 5/3 fiber failed to increase the efficacy of transduction, suggesting limited utility of the hamster model in the context of viruses with this capsid. In ATAP, treatments appeared safe and well-tolerated. Four out of nine melanoma patients treated were evaluable for possible therapy benefit with modified RECIST criteria: one patient had minor response, two had stable disease, and one had progressive disease. Two patients were alive at 559 and 2,149 days after treatment. Ad5/3-D24-GMCSF showed promising efficacy in preclinical studies and possible antitumor activity in melanoma patients refractory to other forms of therapy. This data supports continuing the clinical development of oncolytic adenoviruses for treatment of malignant melanoma. PMID:25821063

  20. Thermostability of multidomain proteins: chimeric mesophilic/thermophilic elongation factors EF-Tu

    Czech Academy of Sciences Publication Activity Database

    Šanderová, Hana; Maloň, Petr; Hůlková, Marta; Jonák, Jiří

    Varšava : FEBS, 2004, s. 7. [FEBS Forum for Young Scientists. Varšava (PL), 24.06.2004-26.06.2004] R&D Projects: GA ČR GA303/02/0689 Institutional research plan: CEZ:AV0Z5052915 Keywords : thermostability * EF-Tu * chimeric protein Subject RIV: EB - Genetics ; Molecular Biology

  1. Thermostability of multidomain proteins: chimeric mesophilic/thermophilic elongation factors EF-Tu

    Czech Academy of Sciences Publication Activity Database

    Šanderová, Hana; Maloň, Petr; Hůlková, Marta; Jonák, Jiří

    Oxford : Blackwell Publishing, 2004, s. 219. [Meeting of the Federation of the European Biochemical Societies /29./. Varšava (PL), 26.06.2004-01.07.2004] R&D Projects: GA ČR GA303/02/0689 Institutional research plan: CEZ:AV0Z5052915 Keywords : thermostability * EF-Tu * chimeric protein Subject RIV: EB - Genetics ; Molecular Biology

  2. Preparation and Characterization of a Novel Chimeric Protein VEGI-CTT in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Jiping Cai

    2008-08-01

    Full Text Available Vascular endothelial cell growth inhibitor (VEGI is a recently identified antiangiogenic cytokine that belongs to the TNF superfamily, and could effectively inhibit endothelial cell proliferation and angiogenesis. Synthetic peptide CTT (CTTHWGFTLC has been found to suppress invasion and migration of both tumor and endothelial cells by potent and selective inhibition of MMP-2 and MMP-9. To prepare chimeric protein VEGI-CTT for more potent antitumor therapy, the recombinant expression vector pET-VEGI-CTT was constructed. This fusion protein was expressed in inclusion bodies in E. coli BL21 (DE3, and was refolded and purified by immobilized metal affinity chromatography using His-tag. Purified VEGI-CTT protein was characterized by proliferation assays of the endothelial cells and casein degradation assay in vitro. The results demonstrated that chimeric protein VEGI-CTT had a potent activity of antiangiogenesis through inhibiting the proliferation of endothelial cells, and could effectively reduce the activity of MMP-2 and MMP-9. The preliminarily in vivo study demonstrated that chimeric protein VEGI-CTT had more potent antitumor activity than VEGI and/or CTT peptide against CA46 human lymphoma xenografts in nude mice. Thus, these facts that are derived from the present study suggest that the chimeric protein VEGI-CTT may be used for tumor therapy in the future.

  3. Trypanosoma cruzi Differentiates and Multiplies within Chimeric Parasitophorous Vacuoles in Macrophages Coinfected with Leishmania amazonensis.

    Science.gov (United States)

    Pessoa, Carina Carraro; Ferreira, Éden Ramalho; Bayer-Santos, Ethel; Rabinovitch, Michel; Mortara, Renato Arruda; Real, Fernando

    2016-05-01

    The trypanosomatids Leishmania amazonensis and Trypanosoma cruzi are excellent models for the study of the cell biology of intracellular protozoan infections. After their uptake by mammalian cells, the parasitic protozoan flagellates L. amazonensis and T. cruzi lodge within acidified parasitophorous vacuoles (PVs). However, whereas L. amazonensis develops in spacious, phagolysosome-like PVs that may enclose numerous parasites, T. cruzi is transiently hosted within smaller vacuoles from which it soon escapes to the host cell cytosol. To investigate if parasite-specific vacuoles are required for the survival and differentiation of T. cruzi, we constructed chimeric vacuoles by infection of L. amazonensis amastigote-infected macrophages with T. cruzi epimastigotes (EPIs) or metacyclic trypomastigotes (MTs). These chimeric vacuoles, easily observed by microscopy, allowed the entry and fate of T. cruzi in L. amazonensis PVs to be dynamically recorded by multidimensional imaging of coinfected cells. We found that although T. cruzi EPIs remained motile and conserved their morphology in chimeric vacuoles, T. cruzi MTs differentiated into amastigote-like forms capable of multiplying. These results demonstrate that the large adaptive vacuoles of L. amazonensis are permissive to T. cruzi survival and differentiation and that noninfective EPIs are spared from destruction within the chimeric PVs. We conclude that T. cruzi differentiation can take place in Leishmania-containing vacuoles, suggesting this occurs prior to their escape into the host cell cytosol. PMID:26975994

  4. Evidence for transcript networks composed of chimeric RNAs in human cells.

    Science.gov (United States)

    Djebali, Sarah; Lagarde, Julien; Kapranov, Philipp; Lacroix, Vincent; Borel, Christelle; Mudge, Jonathan M; Howald, Cédric; Foissac, Sylvain; Ucla, Catherine; Chrast, Jacqueline; Ribeca, Paolo; Martin, David; Murray, Ryan R; Yang, Xinping; Ghamsari, Lila; Lin, Chenwei; Bell, Ian; Dumais, Erica; Drenkow, Jorg; Tress, Michael L; Gelpí, Josep Lluís; Orozco, Modesto; Valencia, Alfonso; van Berkum, Nynke L; Lajoie, Bryan R; Vidal, Marc; Stamatoyannopoulos, John; Batut, Philippe; Dobin, Alex; Harrow, Jennifer; Hubbard, Tim; Dekker, Job; Frankish, Adam; Salehi-Ashtiani, Kourosh; Reymond, Alexandre; Antonarakis, Stylianos E; Guigó, Roderic; Gingeras, Thomas R

    2012-01-01

    The classic organization of a gene structure has followed the Jacob and Monod bacterial gene model proposed more than 50 years ago. Since then, empirical determinations of the complexity of the transcriptomes found in yeast to human has blurred the definition and physical boundaries of genes. Using multiple analysis approaches we have characterized individual gene boundaries mapping on human chromosomes 21 and 22. Analyses of the locations of the 5' and 3' transcriptional termini of 492 protein coding genes revealed that for 85% of these genes the boundaries extend beyond the current annotated termini, most often connecting with exons of transcripts from other well annotated genes. The biological and evolutionary importance of these chimeric transcripts is underscored by (1) the non-random interconnections of genes involved, (2) the greater phylogenetic depth of the genes involved in many chimeric interactions, (3) the coordination of the expression of connected genes and (4) the close in vivo and three dimensional proximity of the genomic regions being transcribed and contributing to parts of the chimeric RNAs. The non-random nature of the connection of the genes involved suggest that chimeric transcripts should not be studied in isolation, but together, as an RNA network. PMID:22238572

  5. Viral Engineering of Chimeric Antigen Receptor Expression on Murine and Human T Lymphocytes.

    Science.gov (United States)

    Hammill, Joanne A; Afsahi, Arya; Bramson, Jonathan L; Helsen, Christopher W

    2016-01-01

    The adoptive transfer of a bolus of tumor-specific T lymphocytes into cancer patients is a promising therapeutic strategy. In one approach, tumor specificity is conferred upon T cells via engineering expression of exogenous receptors, such as chimeric antigen receptors (CARs). Here, we describe the generation and production of both murine and human CAR-engineered T lymphocytes using retroviruses. PMID:27581020

  6. In Silico Design of a Chimeric Protein Containing Antigenic Fragments of Helicobacter pylori; A Bioinformatic Approach

    Science.gov (United States)

    Mohammad, Nazanin; Karsabet, Mehrnaz Taghipour; Amani, Jafar; Ardjmand, Abolfazl; Zadeh, Mohsen Razavi; Gholi, Mohammad Khalifeh; Saffari, Mahmood; Ghasemi, Amir

    2016-01-01

    Helicobacter pylori is a global health problem which has encouraged scientists to find new ways to diagnose, immunize and eradicate the H. pylori infection. In silico studies are a promising approach to design new chimeric antigen having the immunogenic potential of several antigens. In order to obtain such benefit in H. pylori vaccine study, a chimeric gene containing four fragments of FliD sequence (1-600 bp), UreB (327-334 bp),VacA (744-805 bp) and CagL(51-100 bp) which have a high density of B- and T-cell epitopes was designed. The secondary and tertiary structures of the chimeric protein and other properties such as stability, solubility and antigenicity were analyzed. The in silico results showed that after optimizing for the purpose of expression in Escherichia coli BL21, the solubility and antigenicity of the construct fragments were highly retained. Most regions of the chimeric protein were found to have a high antigenic propensity and surface accessibility. These results would be useful in animal model application and accounted for the development of an epitope-based vaccine against the H. pylori. PMID:27335622

  7. Ligand-mediated negative regulation of a chimeric transmembrane receptor tyrosine phosphatase

    DEFF Research Database (Denmark)

    Desai, D M; Sap, J; Schlessinger, J;

    1993-01-01

    inactivate the EGFR-CD45 chimera in a manner that is dependent on dimerization of the chimeric protein. Inactivation of EGFR-CD45 chimera function results in the loss of TCR signaling, indicating that CD45 function is continuously required for TCR-mediated proximal signaling events. These results suggest...

  8. Alloreactive regulatory T cells allow the generation of mixed chimerism and transplant tolerance

    Directory of Open Access Journals (Sweden)

    Paulina eRuiz

    2015-11-01

    Full Text Available The induction of donor-specific transplant tolerance is one of the main goals of modern immunology. Establishment of a mixed chimerism state in the transplant recipient has proven to be a suitable strategy for the induction of long-term allograft tolerance; however, current experimental recipient preconditioning protocols have many side effects, and are not feasible for use in future therapies. In order to improve the current mixed chimerism induction protocols, we developed a non-myeloablative bone-marrow transplant protocol using retinoic acid induced alloantigen-specific Tregs, clinically available immunosuppressive drugs and lower doses of irradiation. We demonstrate that retinoic acid induced alloantigen-specific Tregs in addition to a non-myeloablative bone-marrow transplant protocol generates stable mixed chimerism and induce tolerance to allogeneic secondary skin allografts in mice. Therefore, the establishment of mixed chimerism through the use of donor-specific Tregs rather than non-specific immunosuppression could have a potential use in organ transplantation.

  9. Origination of an X-linked testes chimeric gene by illegitimate recombination in Drosophila.

    Directory of Open Access Journals (Sweden)

    2006-05-01

    Full Text Available The formation of chimeric gene structures provides important routes by which novel proteins and functions are introduced into genomes. Signatures of these events have been identified in organisms from wide phylogenic distributions. However, the ability to characterize the early phases of these evolutionary processes has been difficult due to the ancient age of the genes or to the limitations of strictly computational approaches. While examples involving retrotransposition exist, our understanding of chimeric genes originating via illegitimate recombination is limited to speculations based on ancient genes or transfection experiments. Here we report a case of a young chimeric gene that has originated by illegitimate recombination in Drosophila. This gene was created within the last 2-3 million years, prior to the speciation of Drosophila simulans, Drosophila sechellia, and Drosophila mauritiana. The duplication, which involved the Bällchen gene on Chromosome 3R, was partial, removing substantial 3' coding sequence. Subsequent to the duplication onto the X chromosome, intergenic sequence was recruited into the protein-coding region creating a chimeric peptide with approximately 33 new amino acid residues. In addition, a novel intron-containing 5' UTR and novel 3' UTR evolved. We further found that this new X-linked gene has evolved testes-specific expression. Following speciation of the D. simulans complex, this novel gene evolved lineage-specifically with evidence for positive selection acting along the D. simulans branch.

  10. The rapid generation of chimerical genes expanding protein diversity in zebrafish

    Directory of Open Access Journals (Sweden)

    Zou Ming

    2010-11-01

    Full Text Available Abstract Background Variation of gene number among species indicates that there is a general process of new gene origination. One of the major mechanism providing raw materials for the origin of new genes is gene duplication. Retroposition, as a special type of gene duplication- the RNA-based duplication, has been found to play an important role in new gene evolution in mammals and plants, but little is known about the process in the teleostei genome. Results Here we screened the zebrafish genome for identification of retrocopies and new chimerical retrogenes and investigated their origination and evolution. We identified 652 retrocopies, of which 440 are intact retrogenes and 212 are pseudogenes. Retrocopies have long been considered evolutionary dead ends without functional significance due to the presumption that retrocopies lack the regulatory element needed for expression. However, 437 transcribed retrocopies were identified from all of the retrocopies. This discovery combined with the substitution analysis suggested that the majority of all retrocopies are subject to negative selection, indicating that most of the retrocopies may be functional retrogenes. Moreover, we found that 95 chimerical retrogenes had recruited new sequences from neighboring genomic regions that formed de novo splice sites, thus generating new intron-containing chimeric genes. Based on our analysis of 38 pairs of orthologs between Cyprinus carpio and Danio rerio, we found that the synonymous substitution rate of zebrafish genes is 4.13×10-9 substitution per silent site per year. We also found 10 chimerical retrogenes that were created in the last 10 million years, which is 7.14 times the rate of 0.14 chimerical retrogenes per million years in the primate lineage toward human and 6.25 times the rate of 0.16 chimerical genes per million years in Drosophila. This is among the most rapid rates of generation of chimerical genes, just next to the rice. Conclusion There is

  11. Chimeric Peptides as Implant Functionalization Agents for Titanium Alloy Implants with Antimicrobial Properties

    Science.gov (United States)

    Yucesoy, Deniz T.; Hnilova, Marketa; Boone, Kyle; Arnold, Paul M.; Snead, Malcolm L.; Tamerler, Candan

    2015-04-01

    Implant-associated infections can have severe effects on the longevity of implant devices and they also represent a major cause of implant failures. Treating these infections associated with implants by antibiotics is not always an effective strategy due to poor penetration rates of antibiotics into biofilms. Additionally, emerging antibiotic resistance poses serious concerns. There is an urge to develop effective antibacterial surfaces that prevent bacterial adhesion and proliferation. A novel class of bacterial therapeutic agents, known as antimicrobial peptides (AMPs), are receiving increasing attention as an unconventional option to treat septic infection, partly due to their capacity to stimulate innate immune responses and for the difficulty of microorganisms to develop resistance towards them. While host and bacterial cells compete in determining the ultimate fate of the implant, functionalization of implant surfaces with AMPs can shift the balance and prevent implant infections. In the present study, we developed a novel chimeric peptide to functionalize the implant material surface. The chimeric peptide simultaneously presents two functionalities, with one domain binding to a titanium alloy implant surface through a titanium-binding domain while the other domain displays an antimicrobial property. This approach gains strength through control over the bio-material interfaces, a property built upon molecular recognition and self-assembly through a titanium alloy binding domain in the chimeric peptide. The efficiency of chimeric peptide both in-solution and absorbed onto titanium alloy surface was evaluated in vitro against three common human host infectious bacteria, Streptococcus mutans, Staphylococcus epidermidis, and Escherichia coli. In biological interactions such as occur on implants, it is the surface and the interface that dictate the ultimate outcome. Controlling the implant surface by creating an interface composed chimeric peptides may therefore

  12. Murine immune responses to a Plasmodium vivax-derived chimeric recombinant protein expressed in Brassica napus

    Directory of Open Access Journals (Sweden)

    Chung Nam-Jun

    2011-04-01

    Full Text Available Abstract Background To develop a plant-based vaccine against Plasmodium vivax, two P. vivax candidate proteins were chosen. First, the merozoite surface protein-1 (MSP-1, a major asexual blood stage antigen that is currently considered a strong vaccine candidate. Second, the circumsporozoite protein (CSP, a component of sporozoites that contains a B-cell epitope. Methods A synthetic chimeric recombinant 516 bp gene encoding containing PvMSP-1, a Pro-Gly linker motif, and PvCSP was synthesized; the gene, named MLC, encoded a total of 172 amino acids. The recombinant gene was modified with regard to codon usage to optimize gene expression in Brassica napus. The Ti plasmid inducible gene transfer system was used for MLC chimeric recombinant gene expression in B. napus. Gene expression was confirmed by polymerase chain reaction (PCR, beta-glucuronidase reporter gene (GUS assay, and Western blot. Results The MLC chimeric recombinant protein expressed in B. napus had a molecular weight of approximately 25 kDa. It exhibited a clinical sensitivity of 84.21% (n = 38 and a clinical specificity of 100% (n = 24 as assessed by enzyme-linked immunosorbent assay (ELISA. Oral immunization of BALB/c mice with MLC chimeric recombinant protein successfully induced antigen-specific IgG1 production. Additionally, the Th1-related cytokines IL-12 (p40, TNF, and IFN-γ were significantly increased in the spleens of the BALB/c mice. Conclusions The chimeric MLC recombinant protein produced in B. napus has potential as both as an antigen for diagnosis and as a valuable vaccine candidate for oral immunization against vivax malaria.

  13. Recombinant Newcastle disease virus expressing H9 HA protects chickens against heterologous avian influenza H9N2 virus challenge.

    Science.gov (United States)

    Nagy, Abdou; Lee, Jinhwa; Mena, Ignacio; Henningson, Jamie; Li, Yuhao; Ma, Jingjiao; Duff, Michael; Li, Yonghai; Lang, Yuekun; Yang, Jianmei; Abdallah, Fatma; Richt, Juergen; Ali, Ahmed; García-Sastre, Adolfo; Ma, Wenjun

    2016-05-17

    In order to produce an efficient poultry H9 avian influenza vaccine that provides cross-protection against multiple H9 lineages, two Newcastle disease virus (NDV) LaSota vaccine strain recombinant viruses were generated using reverse genetics. The recombinant NDV-H9Con virus expresses a consensus-H9 hemagglutinin (HA) that is designed based on available H9N2 sequences from Chinese and Middle Eastern isolates. The recombinant NDV-H9Chi virus expresses a chimeric-H9 HA in which the H9 ectodomain of A/Guinea Fowl/Hong Kong/WF10/99 was fused with the cytoplasmic and transmembrane domain of the fusion protein (F) of NDV. Both recombinant viruses expressed the inserted HA stably and grew to high titers. An efficacy study in chickens showed that both recombinant viruses were able to provide protection against challenge with a heterologous H9N2 virus. In contrast to the NDV-H9Chi virus, the NDV-H9Con virus induced a higher hemagglutination inhibition titer against both NDV and H9 viruses in immunized birds, and efficiently inhibited virus shedding through the respiratory route. Moreover, sera collected from birds immunized with either NDV-H9Con or NDV-H9Chi were able to cross-neutralize two different lineages of H9N2 viruses, indicating that NDV-H9Con and NDV-H9Chi are promising vaccine candidates that could provide cross-protection among different H9N2 lineage viruses. PMID:27102817

  14. The initial antibody response to HIV-1: induction of ineffective early B cell responses against GP41 by the transmitted/founder virus

    Energy Technology Data Exchange (ETDEWEB)

    Chavez, Leslie L [Los Alamos National Laboratory; Perelson, Alan [Los Alamos National Laboratory

    2008-01-01

    A window of opportunity for immune responses to extinguish HIV -1 exists from the moment of transmission through establishment of the latent pool of HIV -I-infected cells. A critical time to study the initial immune responses to the transmitted/founder virus is the eclipse phase of HIV-1 infection (time from transmission to the first appearance of plasma virus) but, to date, this period has been logistically difficult to analyze. Studies in non-human primates challenged with chimeric simianhuman immunodeficiency virus have shown that neutralizing antibodies, when present at the time of infection, can prevent virus infection.

  15. Target antigen expression on a professional antigen-presenting cell induces superior proliferative antitumor T-cell responses via chimeric T-cell receptors.

    Science.gov (United States)

    Rossig, Claudia; Bär, Annette; Pscherer, Sibylle; Altvater, Bianca; Pule, Martin; Rooney, Cliona M; Brenner, Malcolm K; Jürgens, Heribert; Vormoor, Josef

    2006-01-01

    Human T cells expressing tumor antigen-specific chimeric receptors fail to sustain their growth and activation in vivo, which greatly reduces their therapeutic value. The defective proliferative response to tumor cells in vitro can partly be overcome by concomitant CD28 costimulatory signaling. We investigated whether T-cell activation via chimeric receptors (chRec) can be further improved by ligand expression on antigen-presenting cells of B-cell origin. We generated Epstein-Barr virus (EBV)-specific cytotoxic T lymphocytes (CTLs) expressing a CD19-specific chRec. These CTLs are provided with native receptor stimulation by autologous EBV-transformed B-lymphoblastoid cell lines (LCLs) but exclusively with chRec (CD19-specific) stimulation by allogeneic, human leukocyte antigen (HLA)-mismatched CD19+ LCLs. CD19zeta-transduced EBV-specific CTLs specifically lysed both allogeneic EBV targets and CD19+ tumor cells through the chRec in a major histocompatibility complex-independent manner, while maintaining their ability to recognize autologous EBV targets through the native T-cell receptor. The transduced CTLs failed to proliferate in response to CD19+ tumor targets even in the presence of CD28 costimulatory signaling. By contrast, CD19 expressed on HLA-mismatched LCL-induced T-cell activation and long-term proliferation that essentially duplicated the result from native receptor stimulation with autologous LCLs, suggesting that a deficit of costimulatory molecules on target cells in addition to CD28 is indeed responsible for inadequate chRec-mediated T-cell function. Hence, effective tumor immunotherapy may be favored if engagement of the chRec on modified T cells is complemented by interaction with multiple costimulator molecules. The use of T cells with native specificity for EBV may be one means of attaining this objective. PMID:16365597

  16. Transduction and selection of human T cells with novel CD34/thymidine kinase chimeric suicide genes for the treatment of graft-versus-host disease.

    Science.gov (United States)

    Rettig, Michael P; Ritchey, Julie K; Meyerrose, Todd E; Haug, Jeffrey S; DiPersio, John F

    2003-07-01

    Clinical trials evaluating the herpes simplex virus thymidine kinase (HSV-tk)/ganciclovir (GCV) suicide gene therapy system for the control of graft-versus-host disease (GVHD) have been limited by low transduction efficiencies and inefficient selection procedures. In this study, we designed and evaluated a novel chimeric suicide gene consisting of the extracellular and transmembrane domains of human CD34 and full-length HSV-tk (DeltaCD34-tk). High-efficiency transfer of DeltaCD34-tk to primary human T cells was accomplished after a single exposure to VSV-G-pseudotyped, Moloney murine leukemia virus-based retrovirus 48 h after activation of human PBMCs with anti-CD3 and anti-CD28 antibodies immobilized on magnetic beads. Using an optimized 5-day transduction and selection procedure, transduction efficiencies averaged 71%, with isolation purities greater than 95% and yields exceeding 90%. The immunoselected T cells were selectively eliminated by GCV (IC(50) approximately 3 nM), maintained a normal subset composition, exhibited a polyclonal TCR Vbeta family repertoire, and contained 5 or 6 vector copies per transduced cell when optimally transduced. No increase in GCV sensitivity was observed upon incorporation of highly active mutant HSV-tk enzymes into the DeltaCD34-tk suicide gene. T cells modified with the DeltaCD34-tk gene using the optimized protocol should improve the overall efficacy of the HSV-tk/GCV suicide gene therapy method of GVHD control. PMID:12842426

  17. Dosimetry of chimeric TNT in lung cancer patients

    International Nuclear Information System (INIS)

    Objective: A mouse-human chimeric Tumor-Necrosis-Therapy (chTNT) monoclonal antibody is directed against single-stranded DNA a universal nuclear antigen accessible in the necrotic cell within most solid tumors, which has potential for the radioimmunotherapy of many solid tumors. The radiation dosimetry of the 131I-chTNT was evaluated in 9 lung cancer patients (age 18-74 years, mean weight (49.6±6.5) kg). Methods: A single intravenous dose of (29.6±3.7) MBq/kg was administered. Blood samples were drawn at different time intervals and urine was collected for up to one week. Tissue distribution was followed for up to one week by gamma camera imaging. The geometric mean of the counts in the whole body scintigram at 0.5 h after infusion was corrected for radioactivity decay from the time of infusion, this value being taken as 100%ID. The geometric mean of the anterior and posterior counts was obtained from selected region of interested (ROI) to determine activity within the critical organs after being subtracted the background activity. Counts from thyroid were obtained from anterior images only. A background region was drawn below the thyroid gland to subtract underlying activity in the neck blood vessels. The residence times for brain, lungs, liver, spleen, kidneys, heart, thyroid and the whole body were computed by dividing the area under their %ID/h curves by the 100%ID value. Before integration, the activity-time curves were fitted to an algebraic function with an exponential tail (r>0.90). The absorbed doses were computed from the residence time according to the Medical Internal Radiation Dose (MIRD) scheme using MIRDOSE 3.0 software. The adult female and male phantoms were selected. The MIRDOSE 3.0 dynamic bladder model was used to calculate residence times for urinary bladder content assuming a urinary elimination fraction of 1.0 with a bladder-voiding interval of 4h. Absorbed doses to tumor tissues were estimated using the same approach taken for normal

  18. Parainfluenza Virus Type 3 Expressing the Native or Soluble Fusion (F) Protein of Respiratory Syncytial Virus (RSV) Confers Protection from RSV Infection in African Green Monkeys

    OpenAIRE

    Tang, Roderick S.; MacPhail, Mia; Schickli, Jeanne H; Kaur, Jasmine; Robinson, Christopher L.; Lawlor, Heather A.; Guzzetta, Jeanne M.; Spaete, Richard R.; Haller, Aurelia A.

    2004-01-01

    Respiratory syncytial virus (RSV) causes respiratory disease in young children, the elderly, and immunocompromised individuals, often resulting in hospitalization and/or death. After more than 40 years of research, a Food and Drug Administration-approved vaccine for RSV is still not available. In this study, a chimeric bovine/human (b/h) parainfluenza virus type 3 (PIV3) expressing the human PIV3 (hPIV3) fusion (F) and hemagglutinin-neuraminidase (HN) proteins from an otherwise bovine PIV3 (b...

  19. Chikungunya Virus

    Science.gov (United States)

    ... Gaines, PhD, MPH, MA, CHES Differentiating Chikungunya From Dengue: A Clinical Challenge For Travelers CDC Travelers' Health Chikungunya Virus Home Prevention Transmission Symptoms & Treatment Geographic Distribution Chikungunya virus in ...

  20. Zika Virus

    Science.gov (United States)

    Zika is a virus that is spread mostly by mosquitoes. A pregnant mother can pass it to ... through blood transfusions. There have been outbreaks of Zika virus in the United States, Africa, Southeast Asia, ...

  1. Chikungunya virus

    Science.gov (United States)

    Chikungunya virus infection; Chikungunya ... Where Chikungunya is found Before 2013, the virus was found in Africa, Asia, Europe, and the Indian and Pacific oceans. In late 2013, outbreaks occurred for the first time in the ...

  2. The assay of thyrotropin receptor antibodies with human TSH/LH-CG chimeric receptor expressed on chinese hamster ovary cells

    International Nuclear Information System (INIS)

    TSH/LH-CG chimera cDNA is transfected to CHO-K1 cell to obtain the chimeric receptor expressed on the cell surface. The optimal conditions for TSAb and TSBAb measurements are determined using chimeric receptors and under these conditions activity of TSAb and TSBAb in the sera of the Graves' patients. The results obtained are compared to those of TSAb assays using FRTL5 cells CHO-TSHR cells which have wild type human TSH receptor. The transfection procedure of chimeric receptor gene to CHO-K1 cells are on going. The optimal conditions for TSAb and TSBAb measurement using chimeric receptor will be determined after success of transfection procedure. If this study is successfully completed, not only the heterogeneity of Graves. IgG but also pathogenesis of Graves' disease will be elucidated. (author). 25 refs

  3. The assay of thyrotropin receptor antibodies with human TSH/LH-CG chimeric receptor expressed on chinese hamster ovary cells

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Ka Hee; Kim, Chang Min [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1996-12-01

    TSH/LH-CG chimera cDNA is transfected to CHO-K1 cell to obtain the chimeric receptor expressed on the cell surface. The optimal conditions for TSAb and TSBAb measurements are determined using chimeric receptors and under these conditions activity of TSAb and TSBAb in the sera of the Graves` patients. The results obtained are compared to those of TSAb assays using FRTL5 cells CHO-TSHR cells which have wild type human TSH receptor. The transfection procedure of chimeric receptor gene to CHO-K1 cells are on going. The optimal conditions for TSAb and TSBAb measurement using chimeric receptor will be determined after success of transfection procedure. If this study is successfully completed, not only the heterogeneity of Graves. IgG but also pathogenesis of Graves` disease will be elucidated. (author). 25 refs.

  4. ECHO virus

    Science.gov (United States)

    Enteric cytopathic human orphan (ECHO) viruses are a group of viruses that lead to gastrointestinal infection and skin rashes. ... Echovirus is one of several families of viruses that affect the ... are common. In the United States, they are most common in ...

  5. Zika Virus

    Science.gov (United States)

    ... Zika Virus | See Q&A —June 21, 2016 Zika Virus Protein Could Be Vaccine Target —May 19, 2016 Research Conducted and Supported by the National Institutes of Health (NIH) in Addressing Zika Virus Disease. Testimony before the House Democratic Steering ...

  6. Transfection of beta-casein chimeric gene and hormonal induction of its expression in primary murine mammary epithelial cells.

    OpenAIRE

    Yoshimura, M.; Oka, T

    1990-01-01

    To study the regulatory sequence elements responsible for casein gene expression, we constructed a chimeric gene containing 5.3 kilobases (kb) of the 5'-flanking sequence and 1.6 kb of the 3'-flanking sequence of the mouse beta-casein gene fused to the bacterial chloramphenicol acetyl-transferase (CAT) gene. The chimeric gene was transfected by the calcium phosphate-precipitation procedure into primary mouse mammary epithelial cells prepared from pregnant mice. The transfection procedure had ...

  7. Capsid coding sequences of foot-and-mouth disease viruses are determinants of pathogenicity in pigs

    DEFF Research Database (Denmark)

    Lohse, Louise; Jackson, Terry; Bøtner, Anette;

    2012-01-01

    The surface exposed capsid proteins, VP1, VP2 and VP3, of foot-and-mouth disease virus (FMDV) determine its antigenicity and the ability of the virus to interact with host-cell receptors. Hence, modification of these structural proteins may alter the properties of the virus. In the present study we...... compared the pathogenicity of different FMDVs in young pigs. In total 32 pigs, 7-weeks-old, were exposed to virus, either by direct inoculation or through contact with inoculated pigs, using cell culture adapted (O1K B64), chimeric (O1K/A-TUR and O1K/O-UKG) or field strain (O-UKG/34/2001) viruses. The O1K...... coding sequences are determinants of FMDV pathogenicity in pigs....

  8. A Modular Vaccine Development Platform Based on Sortase-Mediated Site-Specific Tagging of Antigens onto Virus-Like Particles.

    Science.gov (United States)

    Tang, Shubing; Xuan, Baoqin; Ye, Xiaohua; Huang, Zhong; Qian, Zhikang

    2016-01-01

    Virus-like particles (VLPs) can be used as powerful nanoscale weapons to fight against virus infection. In addition to direct use as vaccines, VLPs have been extensively exploited as platforms on which to display foreign antigens for prophylactic vaccination and immunotherapeutic treatment. Unfortunately, fabrication of new chimeric VLP vaccines in a versatile, site-specific and highly efficient manner is beyond the capability of traditional VLP vaccine design approaches, genetic insertion and chemical conjugation. In this study, we described a greatly improved VLP display strategy by chemoenzymatic site-specific tailoring antigens on VLPs surface with high efficiency. Through the transpeptidation mediated by sortase A, one protein and two epitopes containing N-terminal oligoglycine were conjugated to the LPET motif on the surface of hepatitis B virus core protein (HBc) VLPs with high density. All of the new chimeric VLPs induced strong specific IgG responses. Furthermore, the chimeric VLPs with sortase A tagged enterovirus 71 (EV71) SP70 epitope could elicit effective antibodies against EV71 lethal challenging as well as the genetic insertion chimeric VLPs. The sortase A mediated chemoenzymatic site-specific tailoring of the HBc VLP approach shows great potential in new VLP vaccine design for its simplicity, site specificity, high efficiency, and versatility. PMID:27170066

  9. Suicide Gene Therapy to Increase the Safety of Chimeric Antigen Receptor-Redirected T Lymphocytes

    Directory of Open Access Journals (Sweden)

    Monica Casucci, Attilio Bondanza

    2011-01-01

    Full Text Available Chimeric antigen receptors (CARs are generated by fusing the antigen-binding motif of a monoclonal antibody (mAb with the signal transduction machinery of the T-cell receptor (TCR. The genetic modification of T lymphocytes with chimeric receptors specific for tumor-associated antigens (TAAs allows for the redirection towards tumor cells. Clinical experience with CAR-redirected T cells suggests that antitumor efficacy associates with some degree of toxicity, especially when TAA expression is shared with healthy tissues. This situation closely resembles the case of allogeneic hematopoietic stem cell transplantation (HSCT, wherein allorecognition causes both the graft-versus-leukemia (GVL effect and graft-versus-host disease (GVHD. Suicide gene therapy, i.e. the genetic induction of a conditional suicide phenotype into donor T cells, enables dissociating the GVL effect from GVHD. Applying suicide gene modification to CAR-redirected T cells may therefore greatly increase their safety profile and facilitate their clinical development.

  10. Development of infectious clones of a wild-type Korean rabies virus and evaluation of their pathogenic potential.

    Science.gov (United States)

    Park, Jun-Sun; Kim, Chi-Kyeong; Um, Ji-Hye; Ju, Young Ran; Lee, Yeong Seon; Choi, Young-Ki; Kim, Su Yeon

    2016-09-01

    Most reverse genetic (RG) systems for rabies viruses (RVs) have been constructed on the genome background of laboratory-adapted strains. In this study, we developed an RG system using a Korean wild type (KGH) strain to investigate the pathogenic potential of different strains. We developed a RG system with the KGH strain for the first time. Following the complete genome sequencing of the KGH strain, pKGH infectious clones were constructed using the CMV/T7 promoter, and HamRz and HdvRz were introduced to allow self-cleavage of the synthesized RNA. We successfully recovered the rescued virus by constructing chimeric RVs in which we replaced a part of the construct with the partial gene from the fixed RC-HL strain. The rescued viruses formed clearer and countable plaques in an immunostaining plaque assay, with a distinct plaque morphology. Furthermore, compared with the chimeric RVs, the pKGH/RCinsΔ4 strain containing the KGH strain G protein exhibited a decreased efficiency of cell-to-cell spreading in BHK-21 cells and significantly reduced (100-1000 fold) replication kinetics. However, pKGH/RCinsΔ4 strain-infected mice revealed 100% morbidity at 11days post-infection, whereas other chimeric RV strains showed no mortality. Our RG system is a useful tool for studying differences in the cell-to-cell spreading efficiency and replication with respect to the different internalization patterns of street and fixed laboratory-adapted viruses. PMID:27397101

  11. Very Long Term Stability of Mixed Chimerism after Allogeneic Hematopoietic Stem Cell Transplantation in Patients with Hematologic Malignancies

    Directory of Open Access Journals (Sweden)

    Emmanuel Levrat

    2015-01-01

    Full Text Available The objective of this study is to analyze the evolution of chimerism of all patients transplanted for hematologic malignancies in our unit during a 20-year period, alive without relapse at 1 year after allogeneic hematopoietic stem cell transplantation (HSCT. Chimerism was tested using short tandem repeat polymorphisms after separation into mononuclear cells and granulocytes by Ficoll density gradient centrifugation. Of 155 patients studied, 89 had full chimerism (FC, 36 mononuclear cells mixed chimerism (MNC-MC, and 30 granulocytic MC with or without mononuclear cells MC (Gran-MC. Survival was significantly better in MNC-MC than in Gran-MC patients, with FC patients being intermediate. There was more disease relapse in the Gran-MC group but not in the MNC-MC group as compared to FC. MC was stable up to 21 years in the MNC-MC group and up to 19 years in the Gran-MC group. Of MC patients alive at 10 years, MC persisted in 83% in the MNC-MC and 57% in the Gran-MC groups. In conclusion, mixed chimerism may remain stable over a very long time period. In survivors without relapse at 1 year after HSCT, determining lineage specific chimerism may be useful as outcome differs, MNC-MC being associated with better outcome than Gran-MC.

  12. Skin Recurrence of Transformed Mycosis Fungoides Postumbilical Cord Blood Transplant despite Complete Donor Chimerism

    OpenAIRE

    Rahul Pawar; Anup Kasi Loknath Kumar; Janet Woodroof; Wei Cui; Joseph McGuirk; Sunil Abhyankar; Sid Ganguly; Anurag Singh; Tara Lin; Omar Aljitawi

    2014-01-01

    Background. Allogeneic stem cell transplant is the treatment of choice for systemic cutaneous T-cell lymphoma (CTCL) which provides graft-versus-lymphoma effect. Herein we discuss a case of recurrence of CTCL skin lesions after cord blood transplant in a patient who continued to have 100% donor chimerism in bone marrow. Case Presentation. A 48-year-old female with history of mycosis fungoides (MF) presented with biopsy proven large cell transformation of MF. PET scan revealed multiple adenop...

  13. Bone marrow chimeric mice reveal a dual role for CD36 in Plasmodium berghei ANKA infection

    Directory of Open Access Journals (Sweden)

    Febbraio Maria

    2007-03-01

    Full Text Available Abstract Background Adhesion of Plasmodium-infected red blood cells (iRBC to different host cells, ranging from endothelial to red blood cells, is associated to malaria pathology. In vitro studies have shown the relevance of CD36 for adhesion phenotypes of Plasmodium falciparum iRBC such as sequestration, platelet mediated clumping and non-opsonic uptake of iRBC. Different adhesion phenotypes involve different host cells and are associated with different pathological outcomes of disease. Studies with different human populations with CD36 polymorphisms failed to attribute a clear role to CD36 expression in human malaria. Up to the present, no in vivo model has been available to study the relevance of different CD36 adhesion phenotypes to the pathological course of Plasmodium infection. Methods Using CD36-deficient mice and their control littermates, CD36 bone marrow chimeric mice, expressing CD36 exclusively in haematopoietic cells or in non-haematopoietic cells, were generated. Irradiated CD36-/- and wild type mice were also reconstituted with syngeneic cells to control for the effects of irradiation. The reconstituted mice were infected with Plasmodium berghei ANKA and analysed for the development of blood parasitaemia and neurological symptoms. Results All mice reconstituted with syngeneic bone marrow cells as well as chimeric mice expressing CD36 exclusively in non-haematopoietic cells died from experimental cerebral malaria between day 6 and 12 after infection. A significant proportion of chimeric mice expressing CD36 only in haematopoietic cells did not die from cerebral malaria. Conclusion The analysis of bone marrow chimeric mice reveals a dual role of CD36 in P. berghei ANKA infection. Expression of CD36 in haematopoietic cells, most likely macrophages and dendritic cells, has a beneficial effect that is masked in normal mice by adverse effects of CD36 expression in non-haematopoietic cells, most likely endothelial cells.

  14. Chimerism in M1 plants of Vicia faba, Capsicum annuum and Linum usitatissimum

    International Nuclear Information System (INIS)

    One important task of our group at IAEA is to develop procedures aiming to improve sampling of M2 seeds to facilitate the recovery of a maximum number of induced mutations in crop plants. Results from studies on three species are reported in this paper. Seeds have been mutagen treated and the chimeric M1 plants were progeny tested in M2. The position of the M2 seeds on the M1 plants has been recorded

  15. Oxidative stress and the mechanical properties of naturally occurring chimeric collagen-containing fibers.

    OpenAIRE

    Sun, C.; E. Vaccaro; Waite, J. H.

    2001-01-01

    The byssal threads of marine mussels are a fiber-reinforced composite material. Fibers are continuous, separated by matrix, and consist of chimeric collagens that encompass within the same primary protein structure domains corresponding to collagen, polyhistidine, and either elastin or dragline spider silk. The elastic modulus (stiffness) of the proximal portion of byssal threads was measured by cyclic stress-strain analysis at 50% extension. Before measurement, the threads were conditioned b...

  16. Chimeric nucleolin aptamer with survivin DNAzyme for cancer cell targeted delivery.

    Science.gov (United States)

    Subramanian, Nithya; Kanwar, Jagat R; Akilandeswari, Balachandran; Kanwar, Rupinder K; Khetan, Vikas; Krishnakumar, Subramanian

    2015-04-25

    A chimeric aptamer-DNAzyme conjugate was generated for the first time using a nucleolin aptamer (NCL-APT) and survivin Dz (Sur_Dz) and exhibited the targeted killing of cancer cells. This proof of concept of using an aptamer for the delivery of DNAzyme can be applied to other cancer types to target survivin in cancer cells in a specific manner. PMID:25797393

  17. Chimeric External Control to Quantify Cell Free DNA in Plasma Samples by Real Time PCR

    OpenAIRE

    Eini, Maryam; Behzad-Behbahani, Abbas; Takhshid, Mohammad Ali; Ramezani, Amin; Rafiei Dehbidi, Gholam Reza; Okhovat, Mohammad Ali; Farhadi, Ali; Alavi, Parniyan

    2016-01-01

    Background: DNA isolation procedure can significantly influence the quantification of DNA by real time PCR specially when cell free DNA (cfDNA) is the subject. To assess the extraction efficiency, linearity of the extraction yield, presence of co-purified inhibitors and to avoid problems with fragment size relevant to cfDNA, development of appropriate External DNA Control (EDC) is challenging. Using non-human chimeric nucleotide sequences, an EDC was developed for standardization of qPCR for ...

  18. T cells expressing VHH-directed oligoclonal chimeric HER2 antigen receptors

    DEFF Research Database (Denmark)

    Jamnani, Fatemeh Rahimi; Rahbarizadeh, Fatemeh; Shokrgozar, Mohammad Ali;

    2014-01-01

    Adoptive cell therapy with engineered T cells expressing chimeric antigen receptors (CARs) originated from antibodies is a promising strategy in cancer immunotherapy. Several unsuccessful trials, however, highlight the need for alternative conventional binding domains and the better combination of...... costimulatory endodomains for CAR construction to improve the effector functions of the engineered T cells. Camelid single-domain antibodies (VHHs), which are the smallest single domain antibodies, can endow great targeting ability to CAR-engineered T cells....

  19. Design and Development of Therapies using Chimeric Antigen Receptor-Expressing T cells

    OpenAIRE

    Dotti, Gianpietro; Gottschalk, Stephen; Savoldo, Barbara; Brenner, Malcolm K

    2014-01-01

    Investigators developed chimeric antigen receptors (CARs) for expression on T cells more than 25 years ago. When the CAR is derived from an antibody, the resultant cell should combine the desirable targeting features of an antibody (e.g. lack of requirement for major histocompatibility complex recognition, ability to recognize non-protein antigens) with the persistence, trafficking and effector functions of a T-cell. This article describes how the past two decades have seen a crescendo of res...

  20. Domain exchange: characterization of a chimeric lipase of hepatic lipase and lipoprotein lipase.

    OpenAIRE

    Wong, H; Davis, R. C.; Nikazy, J; Seebart, K E; Schotz, M C

    1991-01-01

    Hepatic lipase and lipoprotein lipase hydrolyze fatty acids from triacylglycerols and are critical in the metabolism of circulating lipoproteins. The two lipases are similar in size and amino acid sequence but are distinguished by functional differences in substrate preference and cofactor requirement. Presumably, these distinctions result from structural differences in functional domains. To begin localization of these domains, a chimeric lipase was constructed composed of the N-terminal 329...

  1. Remote control of therapeutic T cells through a small molecule-gated chimeric receptor

    OpenAIRE

    Wu, Chia-Yung; Kole T Roybal; Puchner, Elias M.; Onuffer, James; Lim, Wendell A.

    2015-01-01

    There is growing promise in using engineered cells as therapeutic agents. For example, synthetic Chimeric Antigen Receptors (CARs) can redirect T cells to recognize and eliminate tumor cells expressing specific antigens. Despite promising clinical results, excessive activity and poor control over such engineered T cells can cause severe toxicities. We present the design of “ON-switch” CARs that enable small molecule-control over T cell therapeutic functions, while still retaining antigen spec...

  2. Identification of chimeric antigen receptors that mediate constitutive or inducible proliferation of T cells

    OpenAIRE

    Frigault, Matthew J.; Lee, Jihyun; Basil, Maria Ciocca; Carpenito, Carmine; Motohashi, Shinichiro; Scholler, John; Kawalekar, Omkar U.; Guedan, Sonia; McGettigan, Shannon E; Posey, Avery D; Ang, Sonny; Cooper, Laurence J. N.; Platt, Jesse M.; Johnson, F. Brad; Paulos, Chrystal M.

    2015-01-01

    This study compared second generation chimeric antigen receptors encoding signaling domains composed of CD28, ICOS and 4-1BB. Here we report that certain CARs endow T cells with the ability to undergo long-term autonomous proliferation. Transduction of primary human T-cell with lentiviral vectors encoding some of the CARs resulted in sustained proliferation for up to three months following a single stimulation through the TCR. Sustained numeric expansion was independent of cognate antigen and...

  3. Topology of the RNA polymerase active center probed by chimeric rifampicin-nucleotide compounds.

    OpenAIRE

    Mustaev, A; Zaychikov, E; Severinov, K.; Kashlev, M; Polyakov, A.; Nikiforov, V.; Goldfarb, A

    1994-01-01

    Spatial organization of the binding sites for the priming substrate, the template DNA, and the transcription inhibitor rifampicin (Rif) in Escherichia coli RNA polymerase (EC 2.7.7.6) was probed with chimeric compounds in which Rif is covalently attached to a ribonucleotide. The compounds bind to RNA polymerase in bifunctional manner and serve as substrates for RNA chain extension, yielding chains up to 8 nucleotides in length, with Rif linked to their 5' termini. These products act as potent...

  4. Combination therapy using chimeric monoclonal antibodies protects mice from lethal H5N1 infection and prevents formation of escape mutants.

    Directory of Open Access Journals (Sweden)

    Mookkan Prabakaran

    Full Text Available BACKGROUND: Given that there is a possibility of a human H5N1 pandemic and the fact that the recent H5N1 viruses are resistant to the anti-viral drugs, newer strategies for effective therapy are warranted. Previous studies show that single mAbs in immune prophylaxis can be protective against H5N1 infection. But a single mAb may not be effective in neutralization of a broad range of different strains of H5N1 and control of potential neutralization escape mutants. METHODS/PRINCIPAL FINDINGS: We selected two mAbs which recognized different epitopes on the hemagglutinin molecule. These two mAbs could each neutralize in vitro escape mutants to the other and in combination could effectively neutralize viruses from clades 0, 1, 2.1, 2.2, 2.3, 4, 7 and 8 of influenza A H5N1 viruses. This combination of chimeric mAbs when administered passively, pre or post challenge with 10 MLD50 (50% mouse lethal dose HPAI H5N1 influenza A viruses could protect 100% of the mice from two different clades of viruses (clades 1 and 2.1. We also tested the efficacy of a single dose of the combination of mAbs versus two doses. Two doses of the combination therapy not only affected early clearance of the virus from the lung but could completely prevent lung pathology of the H5N1 infected mice. No escape variants were detected after therapy. CONCLUSIONS/SIGNIFICANCE: Our studies provide proof of concept that the synergistic action of two or more mAbs in combination is required for preventing the generation of escape mutants and also to enhance the therapeutic efficacy of passive therapy against H5N1 infection. Combination therapy may allow for a lower dose of antibody to be administered for passive therapy of influenza infection and hence can be made available at reduced economic costs during an outbreak.

  5. Development of a high-throughput microfluidic integrated microarray for the detection of chimeric bioweapons.

    Energy Technology Data Exchange (ETDEWEB)

    Sheppod, Timothy; Satterfield, Brent; Hukari, Kyle W.; West, Jason A. A.; Hux, Gary A.

    2006-10-01

    The advancement of DNA cloning has significantly augmented the potential threat of a focused bioweapon assault, such as a terrorist attack. With current DNA cloning techniques, toxin genes from the most dangerous (but environmentally labile) bacterial or viral organism can now be selected and inserted into robust organism to produce an infinite number of deadly chimeric bioweapons. In order to neutralize such a threat, accurate detection of the expressed toxin genes, rather than classification on strain or genealogical decent of these organisms, is critical. The development of a high-throughput microarray approach will enable the detection of unknowns chimeric bioweapons. The development of a high-throughput microarray approach will enable the detection of unknown bioweapons. We have developed a unique microfluidic approach to capture and concentrate these threat genes (mRNA's) upto a 30 fold concentration. These captured oligonucleotides can then be used to synthesize in situ oligonucleotide copies (cDNA probes) of the captured genes. An integrated microfluidic architecture will enable us to control flows of reagents, perform clean-up steps and finally elute nanoliter volumes of synthesized oligonucleotides probes. The integrated approach has enabled a process where chimeric or conventional bioweapons can rapidly be identified based on their toxic function, rather than being restricted to information that may not identify the critical nature of the threat.

  6. Human-animal chimeras: ethical issues about farming chimeric animals bearing human organs.

    Science.gov (United States)

    Bourret, Rodolphe; Martinez, Eric; Vialla, François; Giquel, Chloé; Thonnat-Marin, Aurélie; De Vos, John

    2016-01-01

    Recent advances in stem cells and gene engineering have paved the way for the generation of interspecies chimeras, such as animals bearing an organ from another species. The production of a rat pancreas by a mouse has demonstrated the feasibility of this approach. The next step will be the generation of larger chimeric animals, such as pigs bearing human organs. Because of the dramatic organ shortage for transplantation, the medical needs for such a transgressive practice are indisputable. However, there are serious technical barriers and complex ethical issues that must be discussed and solved before producing human organs in animals. The main ethical issues are the risks of consciousness and of human features in the chimeric animal due to a too high contribution of human cells to the brain, in the first case, or for instance to limbs, in the second. Another critical point concerns the production of human gametes by such chimeric animals. These worst-case scenarios are obviously unacceptable and must be strictly monitored by careful risk assessment, and, if necessary, technically prevented. The public must be associated with this ethical debate. Scientists and physicians have a critical role in explaining the medical needs, the advantages and limits of this potential medical procedure, and the ethical boundaries that must not be trespassed. If these prerequisites are met, acceptance of such a new, borderline medical procedure may prevail, as happened before for in-vitro fertilization or preimplantation genetic diagnosis. PMID:27356872

  7. Skin Recurrence of Transformed Mycosis Fungoides Postumbilical Cord Blood Transplant despite Complete Donor Chimerism

    Directory of Open Access Journals (Sweden)

    Rahul Pawar

    2014-01-01

    Full Text Available Background. Allogeneic stem cell transplant is the treatment of choice for systemic cutaneous T-cell lymphoma (CTCL which provides graft-versus-lymphoma effect. Herein we discuss a case of recurrence of CTCL skin lesions after cord blood transplant in a patient who continued to have 100% donor chimerism in bone marrow. Case Presentation. A 48-year-old female with history of mycosis fungoides (MF presented with biopsy proven large cell transformation of MF. PET scan revealed multiple adenopathy in abdomen and chest suspicious for lymphoma and skin biopsy showed large cell transformation. She was treated with multiple cycles of chemotherapy. Posttherapy PET scan showed resolution of lymphadenopathy. Later she underwent ablative preparative regimen followed by single cord blood transplant. Bone marrow chimerism studies at day +60 after transplant showed 100% donor cells without presence of lymphoma. However 5 months after transplant she had recurrence of MF with the same genotype as prior skin lesion. Bone marrow chimerism study continued to show 100% donor cells. Conclusion. A differential graft-versus-lymphoma effect in our case prevented lymphoma recurrence systemically but failed to do so in skin. We hypothesize that this response may be due to presence of other factors in the bone marrow and lymph node microenvironments preventing recurrence in these sites.

  8. Venturing in coral larval chimerism: a compact functional domain with fostered genotypic diversity.

    Science.gov (United States)

    Rinkevich, Baruch; Shaish, Lee; Douek, Jacob; Ben-Shlomo, Rachel

    2016-01-01

    The globally distributed coral species Pocillopora damicornis is known to release either sexual or asexual derived planula-larvae in various reef locations. Using microsatellite loci as markers, we documented the release of asexually derived chimeric larvae (CL), originating from mosaicked maternal colonies that were also chimeras, at Thai and Philippines reefs. The CL, each presenting different combinations of maternal genotypic constituents, create genetically-complex sets of asexual propagules. This novel mode of inheritance in corals challenges classical postulations of sexual/asexual reproduction traits, as asexual derived CL represent an alliance between genotypes that significantly sways the recruits' absolute fitness. This type of inherited chimerism, while enhancing intra-entity genetic heterogeneity, is an evolutionary tactic used to increase genetic-heterogeneity, primarily in new areas colonized by a limited number of larvae. Chimerism may also facilitate combat global change impacts by exhibiting adjustable genomic combinations of within-chimera traits that could withstand alterable environmental pressures, helping Pocillopora become a successful cosmopolitan species. PMID:26758405

  9. Preparation and Evaluation of Human-Murine Chimeric Antibody against Protective Antigen of Bacillus anthracis

    Directory of Open Access Journals (Sweden)

    Lina Hao

    2014-10-01

    Full Text Available The aim of this research is to develop a human/murine chimeric Fab antibody which neutralizes the anthrax toxin, protective antigen (PA. The chimeric Fab was constructed using variable regions of murine anti-PA monoclonal antibody in combination with constant regions of human IgG. The chimeric PA6-Fab was expressed in E. coli. BL21 and evaluated by ELISA and co-immunoprecipitation- mass spectra. The potency of PA6-Fab to neutralize LeTx was examined in J774A.1 cell viability in vitro and in Fisher 344 rats in vivo. The PA6-Fab did not have domain similarity corresponding to the current anti PA mAbs, but specifically bound to anthrax PA at an affinity of 1.76 nM, and was able to neutralize LeTx in vitro and protected 56.9% cells at 20 μg/mL against anthrax LeTx. One hundred μg PA6-Fab could neutralize 300 μg LeTx in vivo. The PA6-Fab has potential as a therapeutic mAb for treatment of anthrax.

  10. Induced regulatory T cells in allograft tolerance via transient mixed chimerism

    Science.gov (United States)

    Hotta, Kiyohiko; Aoyama, Akihiro; Oura, Tetsu; Yamada, Yohei; Tonsho, Makoto; Huh, Kyu Ha; Kawai, Kento; Schoenfeld, David; Allan, James S.; Madsen, Joren C.; Benichou, Gilles; Smith, Rex-Neal; Colvin, Robert B.; Sachs, David H.; Cosimi, A. Benedict; Kawai, Tatsuo

    2016-01-01

    Successful induction of allograft tolerance has been achieved in nonhuman primates (NHPs) and humans via induction of transient hematopoietic chimerism. Since allograft tolerance was achieved in these recipients without durable chimerism, peripheral mechanisms are postulated to play a major role. Here, we report our studies of T cell immunity in NHP recipients that achieved long-term tolerance versus those that rejected the allograft (AR). All kidney, heart, and lung transplant recipients underwent simultaneous or delayed donor bone marrow transplantation (DBMT) following conditioning with a nonmyeloablative regimen. After DBMT, mixed lymphocyte culture with CFSE consistently revealed donor-specific loss of CD8+ T cell responses in tolerant (TOL) recipients, while marked CD4+ T cell proliferation in response to donor antigens was found to persist. Interestingly, a significant proportion of the proliferated CD4+ cells were FOXP3+ in TOL recipients, but not in AR or naive NHPs. In TOL recipients, CD4+FOXP3+ cell proliferation against donor antigens was greater than that observed against third-party antigens. Finally, the expanded Tregs appeared to be induced Tregs (iTregs) that were converted from non-Tregs. These data provide support for the hypothesis that specific induction of iTregs by donor antigens is key to long-term allograft tolerance induced by transient mixed chimerism. PMID:27446989

  11. Use of retroviral-mediated gene transfer to deliver and test function of chimeric antigen receptors in human T-cells

    Directory of Open Access Journals (Sweden)

    Ana C. Parente-Pereira

    2014-07-01

    Full Text Available Chimeric antigen receptors (CARs are genetically delivered fusion molecules that elicit T-cell activation upon binding of a native cell surface molecule. These molecules can be used to generate a large number of memory and effector T-cells that are capable of recognizing and attacking tumor cells. Most commonly, stable CAR expression is achieved in T-cells using retroviral vectors. In the method described here, retroviral vectors are packaged in a two-step procedure. First, H29D human retroviral packaging cells (a derivative of 293 cells are transfected with the vector of interest, which is packaged transiently in vesicular stomatitis virus (VSV G pseudotyped particles. These particles are used to deliver the vector to PG13 cells, which achieve stable packaging of gibbon ape leukaemia virus (GALV-pseudotyped particles that are suitable for infection of human T-cells. The key advantage of the method reported here is that it robustly generates polyclonal PG13 cells that are 100% positive for the vector of interest. This means that efficient gene transfer may be repeatedly achieved without the need to clone individual PG13 cells for experimental pre-clinical testing. To achieve T-cell transduction, cells must first be activated using a non-specific mitogen. Phytohemagglutinin (PHA provides an economic and robust stimulus to achieve this. After 48-72 h, activated T-cells and virus-conditioned medium are mixed in RetroNectin-coated plasticware, which enhances transduction efficiency. Transduced cells are analyzed for gene transfer efficiency by flow cytometry 48 h following transduction and may then be tested in several assays to evaluate CAR function, including target-dependent cytotoxicity, cytokine production and proliferation.

  12. Expression and immunological characterization of cardamom mosaic virus coat protein displaying HIV gp41 epitopes.

    Science.gov (United States)

    Damodharan, Subha; Gujar, Ravindra; Pattabiraman, Sathyamurthy; Nesakumar, Manohar; Hanna, Luke Elizabeth; Vadakkuppattu, Ramanathan D; Usha, Ramakrishnan

    2013-05-01

    The coat protein of cardamom mosaic virus (CdMV), a member of the genus Macluravirus, assembles into virus-like particles when expressed in an Escherichia coli expression system. The N and C-termini of the coat protein were engineered with the Kennedy peptide and the 2F5 and 4E10 epitopes of gp41 of HIV. The chimeric proteins reacted with sera from HIV positive persons and also stimulated secretion of cytokines by peripheral blood mononuclear cells from these persons. Thus, a system based on the coat protein of CdMV can be used to display HIV-1 antigens. PMID:23668610

  13. Property of hepatitis B virus replication in Tupaia belangeri hepatocytes.

    Science.gov (United States)

    Sanada, Takahiro; Tsukiyama-Kohara, Kyoko; Yamamoto, Naoki; Ezzikouri, Sayeh; Benjelloun, Soumaya; Murakami, Shuko; Tanaka, Yasuhito; Tateno, Chise; Kohara, Michinori

    2016-01-01

    The northern treeshrew (Tupaia belangeri) has been reported to be an effective candidate for animal infection model with hepatitis B virus (HBV). The objective of our study was to analyze the growth characteristics of HBV in tupaia hepatocytes and the host response to HBV infection. We established primary tupaia hepatocytes (3-6-week old tupaia) and infected them with HBV genotypes A, B and C, and all the genotypes proliferated as well as those in human primary hepatocytes (>10(5) copies/ml in culture supernatant). We next generated a chimeric mouse with tupaia liver by transplantation of tupaia primary hepatocytes to urokinase-type plasminogen activator cDNA (cDNA-uPA)/severe combined immunodeficient (SCID) mice and the replacement ratio with tupaia hepatocytes was found to be more than 95%. Infection of chimeric mice with HBV (genotypes B, C, and D) resulted in HBV-DNA level of 10(4)-10(6) copies/ml after 8 weeks of infection, which were almost similar to that in humanized chimeric mouse. In contrast, serum HBV level in adult tupaia (1-year-old tupaia) was quite low (<10(3) copies/ml). Understanding the differences in the response to HBV infection in primary tupaia hepatocytes, chimeric mouse, and adult tupaia will contribute to elucidating the mechanism of persistent HBV infection and viral eradication. Thus, T. belangeri was found to be efficient for studying the host response to HBV infection, thereby providing novel insight into the pathogenesis of HBV. PMID:26654952

  14. Coat protein gene and 3′ non-coding region of tobacco mosaic virus and tomato mosaic virus are associated with viral pathogenesis in Nicotiana tabacum

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The camellia isolate of tomato mosaic virus (ToMV-TL) can induce local necrotic lesions on the inoculated leaves in Nicotiana tabacum, whereas the broad bean isolate of tobacco mosaic virus (TMV-B) produces the mosaic symptom on systemic leaves. To examine viral determinant for differential infection phenotype in N. tabacum, the coat protein gene and the 3′ non-coding region of TMV was replaced with that of ToMV, the chimeric virus induced similar local necrotic lesions to that induced by ToMV. The results indicate that the coat protein gene and the 3′ non-coding region of TMV and ToMV influence the virus-induced pathogenesis in N. tabacum.

  15. Delineation of structural domains involved in the subtype specificity of tachykinin receptors through chimeric formation of substance P/substance K receptors.

    OpenAIRE

    Y. Yokota; Akazawa, C; Ohkubo, H; Nakanishi, S.

    1992-01-01

    The mammalian tachykinin receptors belong to the family of G protein-coupled receptors and consist of the substance P, substance K and neuromedin K receptors (SPR, SKR and NKR). We constructed 14 chimeric receptors in which seven transmembrane segments were sequentially exchanged between the rat SPR and SKR and examined the subtype specificity of the chimeric receptors by radioligand binding and inositol phosphate measurements after transfection into COS cells. All chimeric receptors showed m...

  16. Chimerism Analysis of Cell-Free DNA in Patients Treated with Hematopoietic Stem Cell Transplantation May Predict Early Relapse in Patients with Hematologic Malignancies

    OpenAIRE

    Mahmoud Aljurf; Hala Abalkhail; Amal Alseraihy; Said Y. Mohamed; Mouhab Ayas; Fahad Alsharif; Hazza Alzahrani; Abdullah Al-Jefri; Ghuzayel Aldawsari; Ali Al-Ahmari; Belgaumi, Asim F.; Claudia Ulrike Walter; Hassan El-Solh; Walid Rasheed; Maher Albitar

    2016-01-01

    Background. We studied DNA chimerism in cell-free DNA (cfDNA) in patients treated with HSCT. Methods. Chimerism analysis was performed on CD3+ cells, polymorphonuclear (PMN) cells, and cfDNA using 16 small tandem repeat loci. The resulting labeled PCR-products were size-fractionated and quantified. Results. Analyzing samples from 191 patients treated with HSCT for nonneoplastic hematologic disorders demonstrated that the cfDNA chimerism is comparable to that seen in PMN cells. Analyzing leuke...

  17. Engineering, expression in transgenic plants and characterisation of E559, a rabies virus-neutralising monoclonal antibody.

    Science.gov (United States)

    van Dolleweerd, Craig J; Teh, Audrey Y-H; Banyard, Ashley C; Both, Leonard; Lotter-Stark, Hester C T; Tsekoa, Tsepo; Phahladira, Baby; Shumba, Wonderful; Chakauya, Ereck; Sabeta, Claude T; Gruber, Clemens; Fooks, Anthony R; Chikwamba, Rachel K; Ma, Julian K-C

    2014-07-15

    Rabies post-exposure prophylaxis (PEP) currently comprises administration of rabies vaccine together with rabies immunoglobulin (RIG) of either equine or human origin. In the developing world, RIG preparations are expensive, often in short supply, and of variable efficacy. Therefore, we are seeking to develop a monoclonal antibody cocktail to replace RIG. Here, we describe the cloning, engineering and production in plants of a candidate monoclonal antibody (E559) for inclusion in such a cocktail. The murine constant domains of E559 were replaced with human IgG1κ constant domains and the resulting chimeric mouse-human genes were cloned into plant expression vectors for stable nuclear transformation of Nicotiana tabacum. The plant-expressed, chimeric antibody was purified and biochemically characterized, was demonstrated to neutralize rabies virus in a fluorescent antibody virus neutralization assay, and conferred protection in a hamster challenge model. PMID:24511101

  18. Computer Virus

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Computer viruses are small software programs that are designed to spread from one computerto another and to interfere with computer operation.A virus might delete data on your computer,use your e-mail program to spread itself to othercomputers,or even erase everything on your hard disk.Viruses are most easily spread by attach-ments in e-mail messages or instant messaging messages.That is why it is essential that you never

  19. Risk of hepatitis B virus reactivation in rheumatoid arthritis patients undergoing biologic treatment: Extending perspective from old to newer drugs

    OpenAIRE

    Nard, Francesca De; Todoerti, Monica; Grosso, Vittorio; Monti, Sara; Breda, Silvia; Rossi, Silvia; Montecucco, Carlomaurizio; Caporali, Roberto

    2015-01-01

    Hepatitis B virus (HBV) reactivation in rheumatoid arthritis (RA) patients undergoing biological therapy is not infrequent. This condition can occur in patients with chronic hepatitis B as well as in patients with resolved HBV infection. Current recommendations are mainly focused on prevention and management strategies of viral reactivation under tumor necrosis factor-α inhibitors or chimeric monoclonal antibody rituximab. In recent years, growing data concerning HBV reactivation in RA patien...

  20. Analysis of SAT type foot-and-mouth disease virus capsid proteins and the identification of putative amino acid residues affecting virus stability.

    Science.gov (United States)

    Maree, Francois F; Blignaut, Belinda; de Beer, Tjaart A P; Rieder, Elizabeth

    2013-01-01

    Foot-and-mouth disease virus (FMDV) initiates infection by adhering to integrin receptors on target cells, followed by cell entry and disassembly of the virion through acidification within endosomes. Mild heating of the virions also leads to irreversible dissociation into pentamers, a characteristic linked to reduced vaccine efficacy. In this study, the structural stability of intra- and inter-serotype chimeric SAT2 and SAT3 virus particles to various conditions including low pH, mild temperatures or high ionic strength, was compared. Our results demonstrated that while both the SAT2 and SAT3 infectious capsids displayed different sensitivities in a series of low pH buffers, their stability profiles were comparable at high temperatures or high ionic strength conditions. Recombinant vSAT2 and intra-serotype chimeric viruses were used to map the amino acid differences in the capsid proteins of viruses with disparate low pH stabilities. Four His residues at the inter-pentamer interface were identified that change protonation states at pH 6.0. Of these, the H145 of VP3 appears to be involved in interactions with A141 in VP3 and K63 in VP2, and may be involved in orientating H142 of VP3 for interaction at the inter-pentamer interfaces. PMID:23717387

  1. Analysis of SAT type foot-and-mouth disease virus capsid proteins and the identification of putative amino acid residues affecting virus stability.

    Directory of Open Access Journals (Sweden)

    Francois F Maree

    Full Text Available Foot-and-mouth disease virus (FMDV initiates infection by adhering to integrin receptors on target cells, followed by cell entry and disassembly of the virion through acidification within endosomes. Mild heating of the virions also leads to irreversible dissociation into pentamers, a characteristic linked to reduced vaccine efficacy. In this study, the structural stability of intra- and inter-serotype chimeric SAT2 and SAT3 virus particles to various conditions including low pH, mild temperatures or high ionic strength, was compared. Our results demonstrated that while both the SAT2 and SAT3 infectious capsids displayed different sensitivities in a series of low pH buffers, their stability profiles were comparable at high temperatures or high ionic strength conditions. Recombinant vSAT2 and intra-serotype chimeric viruses were used to map the amino acid differences in the capsid proteins of viruses with disparate low pH stabilities. Four His residues at the inter-pentamer interface were identified that change protonation states at pH 6.0. Of these, the H145 of VP3 appears to be involved in interactions with A141 in VP3 and K63 in VP2, and may be involved in orientating H142 of VP3 for interaction at the inter-pentamer interfaces.

  2. Co-transformation of canola by chimeric chitinase and tlp genes towards improving resistance to Sclerotinia sclerotiorum.

    Science.gov (United States)

    Aghazadeh, Rustam; Zamani, Mohammadreza; Motallebi, Mostafa; Moradyar, Mehdi; Moghadassi Jahromi, Zahra

    2016-09-01

    Canola (Brassica napus) plants were co-transformed with two pathogenesis-related protein genes expressing a Trichoderma atroviride chitinase with a chitin-binding domain (chimeric chitinase) and a thaumatin-like protein (tlp) from Oryza sativa conferring resistance to phytopatogenic fungi by Agrobacterium-mediated transformation. The putative transgenic plants were confirmed by PCR. After measuring the specific activity of the chimeric chitinase and glucanase activity for tlp genes, transgenic plants with high specific activity were selected for southern blot analysis to confirm the copy number of the genes. In vitro assays, the antifungal activity of crude extracted protein against Sclerotinia sclerotiorum showed that the inhibition percentage in double transgenic plants was between 55 and 62, whereas the inhibition percentage in single-gene transformants (chimeric chitinase) ranged from 35 to 45 percent. Importantly, in greenhouse conditions, the double transgenic plants showed significant resistance than the single-gene transformant and wild type plants. The results in T2 generation using the intact leaf inoculation method showed that the average lesion diameters were 10, 14.7 and 29 mm for the double transformant, single-gene transformant and non-transgenic plants, respectively. Combined expression of chimeric chitinase and tlp in transgenic plants showed significantly enhanced resistance against S. sclerotiorum than the one that express single-gene transformant plants. These results suggest that the co-expression of chimeric chitinase and tlp can confer enhanced disease resistance in canola plant. PMID:27430511

  3. Construction and evaluation of a chimeric protein made from Fasciola hepatica leucine aminopeptidase and cathepsin L1.

    Science.gov (United States)

    Hernández-Guzmán, K; Sahagún-Ruiz, A; Vallecillo, A J; Cruz-Mendoza, I; Quiroz-Romero, H

    2016-01-01

    Leucine aminopeptidase (LAP) and cathepsin L1 (CL1) are important enzymes for the pathogenesis and physiology of Fasciola hepatica. These enzymes were analysed in silico to design a chimeric protein containing the most antigenic sequences of LAP (GenBank; AAV59016.1; amino acids 192-281) and CL1 (GenBank CAC12806.1; amino acids 173-309). The cloned 681-bp chimeric fragment (rFhLAP-CL1) contains 270 bp from LAP and 411 bp from CL1, comprising three epitopes, DGRVVHLKY (amino acids 54-62) from LAP, VTGYYTVHSGSEVELKNLV (amino acids 119-137) and YQSQTCLPF (amino acids 161-169) from CL1. The ~25 kDa rFhLAP-CL1 chimeric protein was expressed from the pET15b plasmid in the Rosetta (DE3) Escherichia coli strain. The chimeric protein rFhLAP-CL1, which showed antigenic and immunogenic properties, was recognized in Western blot assays using F. hepatica-positive bovine sera, and induced strong, specific antibody responses following immunization in rabbits. The newly generated chimeric protein may be used as a diagnostic tool for detection of antibodies against F. hepatica in bovine sera and as an immunogen to induce protection against bovine fasciolosis. PMID:25274570

  4. Vaccines prepared from chimeras of foot-and-mouth disease virus (FMDV) induce neutralizing antibodies and protective immunity to multiple serotypes of FMDV.

    OpenAIRE

    Rieder, E; Baxt, B; Lubroth, J; Mason, P W

    1994-01-01

    The G-H loop of VP1 (residues 132 to 159) of foot-and-mouth disease virus (FMDV) is a prominent feature on the virion surface and has an important role in vaccine efficacy, generation of antigenic variants, and cell binding. Using an infectious cDNA of FMDV, we have constructed serotype A viruses in which the G-H loop has been substituted with the homologous sequences from serotype O or C. These chimeric viruses replicated to high titer and displayed plaque morphologies similar to those of wi...

  5. Tomato bushy stunt virus (TBSV), a versatile platform for polyvalent display of antigenic epitopes and vaccine design

    International Nuclear Information System (INIS)

    Viruses-like particles (VLPs) are frequently being used as platforms for polyvalent display of foreign epitopes of interest on their capsid surface to improve their presentation enhancing the antigenicity and host immune response. In the present study, we used the VLPs of Tomato bushy stunt virus (TBSV), an icosahedral plant virus, as a platform to display 180 copies of 16 amino acid epitopes of ricin toxin fused to the C-terminal end of a modified TBSV capsid protein (NΔ52). Expression of the chimeric recombinant protein in insect cells resulted in spontaneous assembly of VLPs displaying the ricin epitope. Cryo-electron microscopy and image reconstruction of the chimeric VLPs at 22 A resolution revealed the locations and orientation of the ricin epitope exposed on the TBSV capsid surface. Furthermore, injection of chimeric VLPs into mice generated antisera that detected the native ricin toxin. The ease of fusing of short peptides of 15-20 residues and their ability to form two kinds (T = 1, T = 3) of bio-nanoparticles that result in the display of 60 or 180 copies of less constrained and highly exposed antigenic epitopes makes TBSV an attractive and versatile display platform for vaccine design.

  6. Neuraminidase and hemagglutinin matching patterns of a highly pathogenic avian and two pandemic H1N1 influenza A viruses.

    Directory of Open Access Journals (Sweden)

    Yonghui Zhang

    Full Text Available BACKGROUND: Influenza A virus displays strong reassortment characteristics, which enable it to achieve adaptation in human infection. Surveying the reassortment and virulence of novel viruses is important in the prevention and control of an influenza pandemic. Meanwhile, studying the mechanism of reassortment may accelerate the development of anti-influenza strategies. METHODOLOGY/PRINCIPAL FINDINGS: The hemagglutinin (HA and neuraminidase (NA matching patterns of two pandemic H1N1 viruses (the 1918 and current 2009 strains and a highly pathogenic avian influenza A virus (H5N1 were studied using a pseudotyped particle (pp system. Our data showed that four of the six chimeric HA/NA combinations could produce infectious pps, and that some of the chimeric pps had greater infectivity than did their ancestors, raising the possibility of reassortment among these viruses. The NA of H5N1 (A/Anhui/1/2005 could hardly reassort with the HAs of the two H1N1 viruses. Many biological characteristics of HA and NA, including infectivity, hemagglutinating ability, and NA activity, are dependent on their matching pattern. CONCLUSIONS/SIGNIFICANCE: Our data suggest the existence of an interaction between HA and NA, and the HA NA matching pattern is critical for valid viral reassortment.

  7. Prokaryotic expression and renaturation of engineering chimeric Fab antibody against human hepatoma

    Institute of Scientific and Technical Information of China (English)

    Jin-Liang Xing; Xiang-Min Yang; Xi-Ying Yao; Fei Song; Zhi-Nan Chen

    2004-01-01

    AIM: To express chimeric Fd (cFd) and chimeric light chain (cL) in E.coli respectively and refold them into chimeric Fab (cFab) antibody.METHODS: cFd and cL genes were respectively inserted into the prokaryotic expression vector pET32a to construct recombinant vectors pET32a/cFd and pET32a/cL. Then,the competent E. colicells were transformed by the recombinant vectors and induced by IPTG. Moreover, a large quantity of cFd and cL expression products were prepared and mixed with equal molar to refold into cFab by gradient dialysis. The refolded products were identified and analyzed by sodium SDS-PAGE, Western blotting,ELISA and HPLC.RESULTS: High efficient prokaryotic expressions of both cFd and cL in the form of non-fusion protein were obtained with the expression levels of 28.3% and 32.3% of total bacteria proteins, respectively. Their relative molecular masses were all 24 ku or so, and both of them mainly existed in the form of inclusion bodies. In addition, cFd and cL were successfully refolded into cFab by gradient dialysis, with about 59.45% of recovery when the starting total protein concentration was 100 μg/mL. The renatured cFab could specifically bind to related antigen with high affinity.CONCLUSION: The cFab antibody against human hepatoma was highly and efficiently expressed and refolded, which laid a solid foundation for studying its application in the treatment of hepatoma.

  8. Chimerism induction by nonmyeloablactive preconditioning and bone marrow infusion in rat small bowel transplantation

    Directory of Open Access Journals (Sweden)

    Bakonyi Neto Alexandre

    2003-01-01

    Full Text Available In our previous work we demonstrated that the use of donor specific bone marrow infusions ( DSBMI after small bowel transplantation did not improve the graft survival after a short course of immunossupression. PURPOSE: In the current study, we evaluated whether recipient preconditioning with different regimens of radiation combined with DSBMI may enhance small bowel allograft survival with minimum recipient morbidity. METHODS: Heterotopic small bowel transplantation (SBTx was performed with Lewis rats as recipients and DA rats as donors, which were immunossupressed with a short course of tacrolimus (FK 506 at 1mg/Kg/day for 5 days and distributed in 4 groups: group 1 (n= 4 without both irradiation and DSBMI; Groups 2 (n= 6, 3 (n= 9 and 4 (n= 6 received 100 x 10(6 DSBM cells at the time of the transplant. Groups 3 and 4 were irradiated with 250 and 400 rd respectively. Animals were examined daily for clinical signs of rejection or GVHD. Blood samples were taken weekly for chimeric studies by FC and intestinal biopsies were performed every 2 weeks. RESULTS: Animals in G1 and G2 had minimal rejection at day 15 after SBTx while GVHD was clinically and histologically characterized in G 3 and G 4. Total chimerism and T-cell chimerism was higher in irradiated groups when compared to non-irradiated groups. With exception of G1 and 2 where rejection was the cause of death, all animals in G3 and 4 died of GVHD. CONCLUSION:We concluded that low cytoreductive of irradiation can successfully decrease the graft rejection but not prevent the occurrence of GVHD.

  9. Design and Construction of Chimeric VP8-S2 Antigen for Bovine Rotavirus and Bovine Coronavirus

    Science.gov (United States)

    Nasiri, Khadijeh; Nassiri, Mohammadreza; Tahmoorespur, Mojtaba; Haghparast, Alireza; Zibaee, Saeed

    2016-01-01

    Purpose: Bovine Rotavirus and Bovine Coronavirus are the most important causes of diarrhea in newborn calves and in some other species such as pigs and sheep. Rotavirus VP8 subunit is the major determinant of the viral infectivity and neutralization. Spike glycoprotein of coronavirus is responsible for induction of neutralizing antibody response. Methods: In the present study, several prediction programs were used to predict B and T-cells epitopes, secondary and tertiary structures, antigenicity ability and enzymatic degradation sites. Finally, a chimeric antigen was designed using computational techniques. The chimeric VP8-S2 antigen was constructed. It was cloned and sub-cloned into pGH and pET32a(+) expression vector. The recombinant pET32a(+)-VP8-S2 vector was transferred into E.oli BL21CodonPlus (DE3) as expression host. The recombinant VP8-S2 protein was purified by Ni-NTA chromatography column. Results: The results of colony PCR, enzyme digestion and sequencing showed that the VP8-S2 chimeric antigen has been successfully cloned and sub-cloned into pGH and pET32a(+).The results showed that E.coli was able to express VP8-S2 protein appropriately. This protein was expressed by induction of IPTG at concentration of 1mM and it was confirmed by Ni–NTA column, dot-blotting analysis and SDS-PAGE electrophoresis. Conclusion: The results of this study showed that E.coli can be used as an appropriate host to produce the recombinant VP8-S2 protein. This recombinant protein may be suitable to investigate to produce immunoglobulin, recombinant vaccine and diagnostic kit in future studies after it passes biological activity tests in vivo in animal model and or other suitable procedure. PMID:27123423

  10. In Vitro and In Vivo Antitumor Effect of Anti-CD33 Chimeric Receptor-Expressing EBV-CTL against CD33+ Acute Myeloid Leukemia

    Directory of Open Access Journals (Sweden)

    A. Dutour

    2012-01-01

    Full Text Available Genetic engineering of T cells with chimeric T-cell receptors (CARs is an attractive strategy to treat malignancies. It extends the range of antigens for adoptive T-cell immunotherapy, and major mechanisms of tumor escape are bypassed. With this strategy we redirected immune responses towards the CD33 antigen to target acute myeloid leukemia. To improve in vivo T-cell persistence, we modified human Epstein Barr Virus-(EBV- specific cytotoxic T cells with an anti-CD33.CAR. Genetically modified T cells displayed EBV and HLA-unrestricted CD33 bispecificity in vitro. In addition, though showing a myeloablative activity, they did not irreversibly impair the clonogenic potential of normal CD34+ hematopoietic progenitors. Moreover, after intravenous administration into CD33+ human acute myeloid leukemia-bearing NOD-SCID mice, anti-CD33-EBV-specific T cells reached the tumor sites exerting antitumor activity in vivo. In conclusion, targeting CD33 by CAR-modified EBV-specific T cells may provide additional therapeutic benefit to AML patients as compared to conventional chemotherapy or transplantation regimens alone.

  11. Rituximab chimeric anti-CD20 monoclonal antibody treatment for adult refractory idiopathic thrombocytopenic purpura

    DEFF Research Database (Denmark)

    Braendstrup, Peter; Bjerrum, Ole W; Nielsen, Ove J;

    2005-01-01

    . Recent studies have shown that rituximab, a chimeric anti-CD20 monoclonal antibody, is useful in the treatment of these patients, with overall response rates of about 50%. Most published reports have included a small number patients including case reports. The present study reports the results of a...... retrospective Danish multicenter study of rituximab in the treatment of adult patients with refractory ITP. Thirty-five patients (median age 52 years, range 17-82 years, 17 males) were included. One patient had immune thrombocytopenia and neutropenia. All patients had received prednisolone (Pred). Next to Pred...

  12. Chimeric antigen receptor T cell therapy: 25years in the making.

    Science.gov (United States)

    Gill, Saar; Maus, Marcela V; Porter, David L

    2016-05-01

    Chimeric antigen receptor (CAR) T cell therapy of cancer is generating enormous enthusiasm. Twenty-five years after the concept was first proposed, major advances in molecular biology, virology, and good manufacturing practices (GMP)-grade cell production have transformed antibody-T cell chimeras from a scientific curiosity to a fact of life for academic cellular immunotherapy researchers and, increasingly, for patients. In this review, we explain the preclinical concept, outline how it has been translated to the clinic, and draw lessons from the first years of CAR T cell therapy for the practicing clinician. PMID:26574053

  13. High affinity mouse-human chimeric Fab against Hepatitis B surface antigen

    OpenAIRE

    Bose, Biplab; Khanna, Navin; Acharya, Subrat K; Sinha, Subrata

    2005-01-01

    AIM: Passive immunotherapy using antibody against hepatitis B surface antigen (HBsAg) has been advocated in certain cases of Hepatitis B infection. We had earlier reported on the cloning and expression of a high affinity scFv derived from a mouse monoclonal (5S) against HBsAg. However this mouse antibody cannot be used for therapeutic purposes as it may elicit anti-mouse immune responses. Chimerization by replacing mouse constant domains with human ones can reduce the immunogenicity of this a...

  14. T cells expressing chimeric antigen receptors can cause anaphylaxis in humans

    OpenAIRE

    Maus, Marcela V.; Haas, Andrew R; Beatty, Gregory L.; Albelda, Steven M.; Levine, Bruce L.; Liu, Xiaojun; Zhao, Yangbing; Kalos, Michael; June, Carl H.

    2013-01-01

    T cells can be redirected to overcome tolerance to cancer by engineering with integrating vectors to express a chimeric antigen receptor (CAR). In preclinical models, we have previously demonstrated that transfection of T cells with messenger RNA (mRNA) coding for a CAR is an alternative strategy that has antitumor efficacy and the potential to evaluate the on-target off-tumor toxicity of new CAR targets safely due to transient mRNA CAR expression. Here, we report the safety observed in four ...

  15. The chimeric VirA-tar receptor protein is locked into a highly responsive state.

    OpenAIRE

    Turk, S C; van Lange, R P; Sonneveld, E; Hooykaas, P J

    1993-01-01

    The wild-type VirA protein is known to be responsive not only to phenolic compounds but also to sugars via the ChvE protein (G. A. Cangelosi, R. G. Ankenbauer, and E. W. Nester, Proc. Natl. Acad. Sci. USA 87:6708-6712, 1990, and N. Shimoda, A. Toyoda-Yamamoto, J. Nagamine, S. Usami, M. Katayama, Y. Sakagami, and Y. Machida, Proc. Natl. Acad. Sci. USA 87:6684-6688, 1990). It is shown here that the mutant VirA(Ser-44, Arg-45) protein and the chimeric VirA-Tar protein are no longer responsive to...

  16. Multi-petal cyclamen flowers produced by AGAMOUS chimeric repressor expression

    OpenAIRE

    Yuri Tanaka; Yoshimi Oshima; Tomomichi Yamamura; Masao Sugiyama; Nobutaka Mitsuda; Norihiro Ohtsubo; Masaru Ohme-Takagi; Teruhiko Terakawa

    2013-01-01

    Cyclamen persicum (cyclamen) is a commercially valuable, winter-blooming perennial plant. We cloned two cyclamen orthologues of AGAMOUS (AG), CpAG1 and CpAG2, which are mainly expressed in the stamen and carpel, respectively. Cyclamen flowers have 5 petals, but expression of a chimeric repressor of CpAG1 (CpAG1-SRDX) caused stamens to convert into petals, resulting in a flower with 10 petals. By contrast, CpAG2-SRDX only caused incomplete formation of stamens and carpels. Expression in Arabid...

  17. Brief Report: HIV-1 Tropism During Primary Infections in France: 1996-2014.

    Science.gov (United States)

    Raymond, Stéphanie; Nicot, Florence; Sauné, Karine; Cazabat, Michelle; Pasquier, Christophe; Massip, Patrice; Marchou, Bruno; Delobel, Pierre; Izopet, Jacques

    2016-08-01

    HIV-1 was mainly CCR5 tropic in recent seroconverters. We analyzed the coreceptor use in 239 primary HIV-1 infections (PHIs) between 1996 and 2014 using a validated recombinant virus phenotypic entry assay. CXCR4-using viruses were detected in 8.3%, 3.8%, and 6.1% of PHIs from 1996 to 2004, 2005 to 2009, and 2010 to 2014, respectively. The presence of CXCR4-using viruses was associated with the virological failure of antiretroviral treatment initiated during PHI (odds ratio, 7.9; 95% confidence interval, 1.1 to 56.5). The phenotypic tropism assay data show that the prevalence of X4 tropic transmitted viruses was stable in this French cohort of PHIs between 1996 and 2014. PMID:26959188

  18. A Rapid and Improved Method to Generate Recombinant Dengue Virus Vaccine Candidates.

    Science.gov (United States)

    Govindarajan, Dhanasekaran; Guan, Liming; Meschino, Steven; Fridman, Arthur; Bagchi, Ansu; Pak, Irene; Meulen, Jan Ter; Casimiro, Danilo R; Bett, Andrew J

    2016-01-01

    Dengue is one of the most important mosquito-borne infections accounting for severe morbidity and mortality worldwide. Recently, the tetravalent chimeric live attenuated Dengue vaccine Dengvaxia® was approved for use in several dengue endemic countries. In general, live attenuated vaccines (LAV) are very efficacious and offer long-lasting immunity against virus-induced disease. Rationally designed LAVs can be generated through reverse genetics technology, a method of generating infectious recombinant viruses from full length cDNA contained in bacterial plasmids. In vitro transcribed (IVT) viral RNA from these infectious clones is transfected into susceptible cells to generate recombinant virus. However, the generation of full-length dengue virus cDNA clones can be difficult due to the genetic instability of viral sequences in bacterial plasmids. To circumvent the need for a single plasmid containing a full length cDNA, in vitro ligation of two or three cDNA fragments contained in separate plasmids can be used to generate a full-length dengue viral cDNA template. However, in vitro ligation of multiple fragments often yields low quality template for IVT reactions, resulting in inconsistent low yield RNA. These technical difficulties make recombinant virus recovery less efficient. In this study, we describe a simple, rapid and efficient method of using LONG-PCR to recover recombinant chimeric Yellow fever dengue (CYD) viruses as potential dengue vaccine candidates. Using this method, we were able to efficiently generate several viable recombinant viruses without introducing any artificial mutations into the viral genomes. We believe that the techniques reported here will enable rapid and efficient recovery of recombinant flaviviruses for evaluation as vaccine candidates and, be applicable to the recovery of other RNA viruses. PMID:27008550

  19. Dizygotic monochorionic twin pregnancy conceived following intracytoplasmic sperm injection treatment and complicated by twin-twin transfusion syndrome and blood chimerism

    DEFF Research Database (Denmark)

    Ekelund, Charlotte Kvist; Skibsted, L.; Søgaard, Kirsten; Main, Katharina Maria; Dziegiel, M.H.; Schwartz, M.; Moeller, N.; Roos, L.; Tabor, A.

    2008-01-01

    were phenotypically a normal male and a normal female. Histology of the placenta showed it to be monochorionic diamniotic. Blood chimerism was found postnatally as both infants had the karyotypes 46,XX[13]/46,XY[17]. Chimerism was not found in cells from a buccal swab at 6 months of age. This is one of...

  20. T-cell chimerism is valuable in predicting early mortality in steroid-resistant acute graft-versus-host disease after myeloablative allogeneic cell transplantation

    DEFF Research Database (Denmark)

    Minculescu, Lia; Madsen, Hans O.; Sengeløv, Henrik

    2014-01-01

    The main aim of this study was to evaluate the impact of early T-cell chimerism status on the incidence and clinical course of acute graft-versus-host disease (aGVHD) in allogeneic transplant recipients after myeloablative conditioning. Of 62 patients, 38 (61%) had complete T-cell donor chimerism...

  1. Pre-clinical evaluation of CD38 chimeric antigen receptor engineered T cells for the treatment of multiple myeloma.

    Science.gov (United States)

    Drent, Esther; Groen, Richard W J; Noort, Willy A; Themeli, Maria; Lammerts van Bueren, Jeroen J; Parren, Paul W H I; Kuball, Jürgen; Sebestyen, Zsolt; Yuan, Huipin; de Bruijn, Joost; van de Donk, Niels W C J; Martens, Anton C M; Lokhorst, Henk M; Mutis, Tuna

    2016-05-01

    Adoptive transfer of chimeric antigen receptor-transduced T cells is a promising strategy for cancer immunotherapy. The CD38 molecule, with its high expression on multiple myeloma cells, appears a suitable target for antibody therapy. Prompted by this, we used three different CD38 antibody sequences to generate second-generation retroviral CD38-chimeric antigen receptor constructs with which we transduced T cells from healthy donors and multiple myeloma patients. We then evaluated the preclinical efficacy and safety of the transduced T cells. Irrespective of the donor and antibody sequence, CD38-chimeric antigen receptor-transduced T cells proliferated, produced inflammatory cytokines and effectively lysed malignant cell lines and primary malignant cells from patients with acute myeloid leukemia and multi-drug resistant multiple myeloma in a cell-dose, and CD38-dependent manner, despite becoming CD38-negative during culture. CD38-chimeric antigen receptor-transduced T cells also displayed significant anti-tumor effects in a xenotransplant model, in which multiple myeloma tumors were grown in a human bone marrow-like microenvironment. CD38-chimeric antigen receptor-transduced T cells also appeared to lyse the CD38(+) fractions of CD34(+) hematopoietic progenitor cells, monocytes, natural killer cells, and to a lesser extent T and B cells but did not inhibit the outgrowth of progenitor cells into various myeloid lineages and, furthermore, were effectively controllable with a caspase-9-based suicide gene. These results signify the potential importance of CD38-chimeric antigen receptor-transduced T cells as therapeutic tools for CD38(+) malignancies and warrant further efforts to diminish the undesired effects of this immunotherapy using appropriate strategies. PMID:26858358

  2. In vivo tumor localization and biodistribution in the human tumor xenografts models of an anti-CD71 mouse/human chimeric antibody

    International Nuclear Information System (INIS)

    Objective: In order to investigate the tumor localization and biodistribution of the anti-CD71 mouse/human chimeric antibody (D2C). Methods: The tumor localization and biodistribution of the chimeric antibody (D2C) were observed by labeling the chimeric Ab with radioiodine (131I) and injecting it into nude mice (Balb/c nu/nu) transplanted with human hepatocellular carcinoma cells (SMMC-7721). Results: The labeled chimeric Ab (D2C), with intraperitoneal as well as tumor regional administration, was significantly localized in the tumor and the location of the tumor was successfully visualized by SPECT. The in vivo D2C Ab's biodistribution of organs and tissues showed that non-specific binding in the tumor regional administration was lower than those in the intraperitoneal. Conclusion: The human/mouse chimeric antibody (D2C) can exert in specific tumor localization in vivo and can be utilized for radio-immunoimaging

  3. Computer viruses

    Science.gov (United States)

    Denning, Peter J.

    1988-01-01

    The worm, Trojan horse, bacterium, and virus are destructive programs that attack information stored in a computer's memory. Virus programs, which propagate by incorporating copies of themselves into other programs, are a growing menace in the late-1980s world of unprotected, networked workstations and personal computers. Limited immunity is offered by memory protection hardware, digitally authenticated object programs,and antibody programs that kill specific viruses. Additional immunity can be gained from the practice of digital hygiene, primarily the refusal to use software from untrusted sources. Full immunity requires attention in a social dimension, the accountability of programmers.

  4. Cross-presentation of HCMV chimeric protein enables generation and measurement of polyclonal T cells.

    Science.gov (United States)

    Nguyen, Thi H O; Sullivan, Lucy C; Kotsimbos, Tom C; Schwarer, Anthony P; Mifsud, Nicole A

    2010-08-01

    CD8(+) T cell immunity has a critical function in controlling human cytomegalovirus (HCMV) infection. In immunocompromized individuals, HCMV reactivation or disease can lead to increased morbidity and mortality, particularly in transplant recipients. In this setting, adoptive transfer of HCMV-specific CD8(+) T cells is a promising vaccine strategy to restore viral immunity, with most clinical approaches focussing on the use of peptides for the generation of single epitope-specific CD8(+) T cells. We show that using an IE1-pp65 chimeric protein as the antigen source promotes effective cross-presentation, by monocyte-derived dendritic cells (MoDCs), to generate polyclonal CD8(+) T cell epitopes. By exploring human leukocyte antigen (HLA)-restricted immunodominance hierarchies both within and across two immunodominant proteins, we show that HLA-B7 epitopes elicit higher CD8(+) T cell responses compared with HLA-A1, -A2 or -B8. This study provides important evidence highlighting both the efficacy of the IE1-pp65 chimeric protein and the importance of immunodominance in designing future therapeutic vaccines. PMID:20195281

  5. Use of recombinant chimeric antigens for the serodiagnosis of Mycoplasma pneumoniae infection.

    Science.gov (United States)

    Montagnani, F; De Paolis, F; Beghetto, E; Gargano, N

    2010-11-01

    In this paper, we have evaluated the diagnostic utility of three antigenic regions of the Mycoplasma pneumoniae P1, P30, and MPN456 gene products in order to replace the soluble, whole-cell bacterial extract in serological assays. Antigenic regions, being previously identified as B-cell epitopes, were used individually or assembled in a recombinant chimeric antigen by genetic engineering. Paired serum samples from 47 patients with M. pneumoniae infection and from 39 subjects with a clinical picture of atypical pneumonia but without a defined diagnosis of M. pneumoniae infection were included. Immunoglobulin G (IgG) antibodies against epitopes carried by recombinant antigens were measured by performing recombinant enzyme-linked immunosorbent assays (Rec-ELISAs). Rec-ELISA results were compared to those obtained by a commercial assay using the whole-cell Mycoplasma antigen. Our study demonstrates that all IgG Rec-ELISAs using recombinant antigens have better sensitivity with respect to the commercial assay. Furthermore, we show that the use of chimeric antigens improve the performance of the assays. The use of recombinant antigens is effective in distinguishing M. pneumoniae-infected patients from uninfected individuals and shows that immunoassays based on recombinant antigens could provide the basis for standardized commercial tests for the serodiagnosis of M. pneumoniae diseases. PMID:20632053

  6. Establishment of permanent chimerism in a lactate dehydrogenase-deficient mouse mutant with hemolytic anemia

    International Nuclear Information System (INIS)

    Pluripotent hemopoietic stem cell function was investigated in the homozygous muscle type lactate dehydrogenase (LDH-A) mutant mouse using bone marrow transplantation experiments. Hemopoietic tissues of LDH-A mutants showed a marked decreased in enzyme activity that was associated with severe hemolytic anemia. This condition proved to be transplantable into wild type mice (+/+) through total body irradiation (TBI) at a lethal dose of 8.0 Gy followed by engraftment of mutant bone marrow cells. Since the mutants are extremely radiosensitive (lethal dose50/30 4.4 Gy vs 7.3 Gy in +/+ mice), 8.0-Gy TBI followed by injection of even high numbers of normal bone marrow cells did not prevent death within 5-6 days. After a nonlethal dose of 4.0 Gy and grafting of normal bone marrow cells, a transient chimerism showing peripheral blood characteristics of the wild type was produced that returned to the mutant condition within 12 weeks. The transfusion of wild type red blood cells prior to and following 8.0-Gy TBI and reconstitution with wild type bone marrow cells prevented the early death of the mutants and permanent chimerism was achieved. The chimeras showed all hematological parameters of wild type mice, and radiosensitivity returned to normal. It is concluded that the mutant pluripotent stem cells are functionally comparable to normal stem cells, emphasizing the significance of this mouse model for studies of stem cell regulation

  7. Co-receptor and co-stimulation blockade for mixed chimerism and tolerance without myelosuppressive conditioning

    Directory of Open Access Journals (Sweden)

    Fairchild Paul J

    2006-04-01

    Full Text Available Abstract Background A major challenge in the application of marrow transplantation as a route to immunological tolerance of a transplanted organ is to achieve hematopoietic stem cell (HSC engraftment with minimal myelosuppressive treatments. Results We here describe a combined antibody protocol which can achieve long-term engraftment with clinically relevant doses of MHC-mismatched bone marrow, without the need for myelosuppressive drugs. Although not universally applicable in all strains, we achieved reliable engraftment in permissive strains with a two-stage strategy: involving first, treatment with anti-CD8 and anti-CD4 in advance of transplantation; and second, treatment with antibodies targeting CD4, CD8 and CD40L (CD154 at the time of marrow transplantation. Long-term mixed chimerism through co-receptor and co-stimulation blockade facilitated tolerance to donor-type skin grafts, without any evidence of donor-antigen driven regulatory T cells. Conclusion We conclude that antibodies targeting co-receptor and co-stimulatory molecules synergise to enable mixed hematopoietic chimerism and central tolerance, showing that neither cytoreductive conditioning nor 'megadoses' of donor bone marrow are required for donor HSC to engraft in permissive strains.

  8. The identification of a spontaneous 47, XX, +21/46, XY chimeric fetus with male genitalia

    Directory of Open Access Journals (Sweden)

    Lee Kuei-Fang

    2012-09-01

    Full Text Available Abstract Background Approximately 30 sex-chromosome discordant chimera cases have been reported to date, of which only four cases carried trisomy 21. Here, we present an additional case, an aborted fetus with a karyotype of 47,XX, +21/46,XY. Case presentation Autopsy demonstrated that this fetus was normally developed and had male genitalia. Major characteristics of Down syndrome were not observed except an enlarged gap between the first and second toes. Karyotyping of tissues cultured from the fetus revealed the same chimeric chromosomal composition detected in the amniotic fluid but with a different ratio of [47,XX,+21] to [46,XY]. Further short tandem repeat analysis indicated a double paternal contribution and single maternal contribution to the fetus, with the additional chromosome 21 in the [47,XX,+21] cell lineage originating from the paternal side. Conclusion We thus propose that this chimeric fetus was formed via the dispermic fertilization of a parthenogenetic ovum with one (Y sperm and one (X,+21 sperm.

  9. Enhanced antigen detection in immunohistochemical staining using a 'digitized' chimeric antibody.

    Science.gov (United States)

    Eng, Hui-Yan; Wang, Cheng-I; Xue, Yuezhen; Lee, Chia-Yin; Zulkifli, Sarah Binte; Chiam, Poh-Cheang; Ghadessy, Farid J; Lane, David P

    2016-01-01

    The immunohistochemical (IHC) staining of mouse tissue sections using antibodies of mouse origin can result in high nonspecific background due to the staining of endogenous immunoglobulins (Igs) by enzyme-conjugated secondary antibodies. In order to obviate this issue, we developed a chimeric mouse-human anti-p53 monoclonal antibody (MH242) by grafting the variable regions of a known mouse antibody into a human Ig scaffold. This facilitated use of an anti-human secondary antibody, and resulted in near-zero background when compared with its parental mouse monoclonal antibody (PAb242). Furthermore, the chimeric antibody enabled reproducible detection of mutant p53 (homozygous R172H) expression in mouse tissue, an observation hitherto largely equivocal based on the use of existing antibodies. The approach we describe leads to the generation of tractable antibody reagents, whose integrity can be readily verified through DNA sequencing of expressor plasmids. The wide-spread adoption of such 'digitized' antibodies should reduce experimental disparities that can commonly arise through variations in antibody quality. PMID:26508747

  10. EspA-Intimin chimeric protein, a candidate vaccine against Escherichia coli O157:H7.

    Directory of Open Access Journals (Sweden)

    Hamid Sedighian Rad

    2013-09-01

    Full Text Available Enterohemorrhagic Escherichia coli (EHEC O157:H7 is an important enteric pathogen in human causing bloody or nonbloody diarrhea, which may be complicated by hemolytic uremic syndrome (HUS. Cattle are an important reservoir of EHEC. This research aims at vaccination with a divalent chimer protein composed of EspA120 and Intimin 282 and its preventive effect of EHEC O157 colonization in mice rectal epithelium.A divalent recombinant EspA-Intimin (EI protein containing EspA120 and Intimin280 attached with a linker was amplified from a trivalent construct and cloned in pET-28a (+ vector. The immunization was conducted in mice after expression and purification of the recombinant EI (rEI.Mice subcutaneously immunized with rEI, elicited significant rEI specific serum IgG antibodies and showed significantly decreased E.coli O157:H7 shedding compared to the control group.The chimeric recombinant protein induced strong humoral response as well as protection against oral challenges with live E.coli O157:H7.

  11. Development of GR/MR Chimeric Receptors and Their Response to Steroid Hormones

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    We have established an effective and reliable technique of developing GR/MR chimeric receptors by DNA homologous recombination. To develop the method we transformed several different E. coli strains with a linearized plasmid containing full length of mGR(mouse GR) and hormone binding domain(HBD) of rMR(rat MR), the linear DNA undergoes recombination due to the homology of the mGR and the rMR and recircularize , and propagation in E. coli. PCR was performed to screen correct construction in which fusion between GR and MR took place. The constructs were digested with appropriate restriction endonucleases to test probable fusion sites of GR and HBD of MR. Precise fusion sites of GR and MR for constructs AB1157 # 2 , AB1157 # 18, AB 1157 # 22, AB1157 # 32, CMK603 # 6 were verified by DNA sequencing. Trans fection of COS- 7 cells with the constructs and subsequent treatment of transfected COS-7 cells with steroid hormones were carried out, the results showed that the constructs gave response to tested hormones. The study suggested that the GR/MR chimeric receptors can give rise to fusion proteins and their interactive function between hormone and receptor.

  12. Simulating aerosols over Arabian Peninsula with CHIMERE: Sensitivity to soil, surface parameters and anthropogenic emission inventories

    Science.gov (United States)

    Beegum, S. Naseema; Gherboudj, Imen; Chaouch, Naira; Couvidat, Florian; Menut, Laurent; Ghedira, Hosni

    2016-03-01

    A three dimensional chemistry transport model, CHIMERE, was used to simulate the aerosol optical depths (AOD) over the Arabian Peninsula desert with an offline coupling of Weather Research and Forecasting (WRF) model. The simulations were undertaken with: (i) different horizontal and vertical configurations, (ii) new datasets derived for soil/surface properties, and (iii) EDGAR-HTAP anthropogenic emissions inventories. The model performance evaluations were assessed: (i) qualitatively using MODIS (Moderate-Resolution Imaging Spectroradiometer) deep blue (DB) AOD data for the two local dust events of August 6th and 23rd (2013), and (ii) quantitatively using AERONET (Aerosol Robotic Network) AOD observations, CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) aerosol extinction profiles, and AOD simulations from various forecast models. The model results were observed to be highly sensitive to erodibility and aerodynamic surface roughness length. The use of new datasets on soil erodibility, derived from the MODIS reflectance, and aerodynamic surface roughness length (z0), derived from the ERA-Interim datasets, significantly improved the simulation results. Simulations with the global EDGAR-HTAP anthropogenic emission inventories brought the simulated AOD values closer to the observations. Performance testing of the adapted model for the Arabian Peninsula domain with improved datasets showed good agreement between AERONET AOD measurements and CHIMERE simulations, where the correlation coefficient (R) is 0.6. Higher values of the correlation coefficients and slopes were observed for the dusty periods compared to the non-dusty periods.

  13. Stoichiometry of monoclonal antibody neutralization of T-cell line-adapted human immunodeficiency virus type 1

    DEFF Research Database (Denmark)

    Schønning, Kristian; Lund, O; Lund, O S; Hansen, J E

    1999-01-01

    In order to study the stoichiometry of monoclonal antibody (MAb) neutralization of T-cell line-adapted human immunodeficiency virus type 1 (HIV-1) in antibody excess and under equilibrium conditions, we exploited the ability of HIV-1 to generate mixed oligomers when different env genes are...... coexpressed. By the coexpression of Env glycoproteins that either can or cannot bind a neutralizing MAb in an env transcomplementation assay, virions were generated in which the proportion of MAb binding sites could be regulated. As the proportion of MAb binding sites in Env chimeric virus increased, MAb...

  14. Stoichiometry of monoclonal antibody neutralization of T-cell line-adapted human immunodeficiency virus type 1

    DEFF Research Database (Denmark)

    Schønning, Kristian; Lund, O; Lund, O S; Hansen, J E

    1999-01-01

    In order to study the stoichiometry of monoclonal antibody (MAb) neutralization of T-cell line-adapted human immunodeficiency virus type 1 (HIV-1) in antibody excess and under equilibrium conditions, we exploited the ability of HIV-1 to generate mixed oligomers when different env genes are...... data could not exclude the existence of a threshold for neutralization. However, results from MAb neutralization of chimeric virus containing wild-type Env and Env defective in CD4 binding was readily explained by a model of incremental MAb neutralization. In summary, the data indicate that MAb...

  15. Zika Virus.

    Science.gov (United States)

    Phillips, Jennan A; Neyland, Anavernyel

    2016-08-01

    Zika virus (ZIKV) infections are the latest global public health emergency. Occupational health nurses can protect society by educating workers, women of childbearing age, and others traveling in ZIKV-infected areas about prevention strategies. PMID:27411846

  16. HIV restriction by APOBEC3 in humanized mice.

    Directory of Open Access Journals (Sweden)

    John F Krisko

    2013-03-01

    Full Text Available Innate immune restriction factors represent important specialized barriers to zoonotic transmission of viruses. Significant consideration has been given to their possible use for therapeutic benefit. The apolipoprotein B mRNA editing enzyme catalytic polypeptide 3 (APOBEC3 family of cytidine deaminases are potent immune defense molecules capable of efficiently restricting endogenous retroelements as well as a broad range of viruses including Human Immunodeficiency virus (HIV, Hepatitis B virus (HBV, Human Papilloma virus (HPV, and Human T Cell Leukemia virus (HTLV. The best characterized members of this family are APOBEC3G (A3G and APOBEC3F (A3F and their restriction of HIV. HIV has evolved to counteract these powerful restriction factors by encoding an accessory gene designated viral infectivity factor (vif. Here we demonstrate that APOBEC3 efficiently restricts CCR5-tropic HIV in the absence of Vif. However, our results also show that CXCR4-tropic HIV can escape from APOBEC3 restriction and replicate in vivo independent of Vif. Molecular analysis identified thymocytes as cells with reduced A3G and A3F expression. Direct injection of vif-defective HIV into the thymus resulted in viral replication and dissemination detected by plasma viral load analysis; however, vif-defective viruses remained sensitive to APOBEC3 restriction as extensive G to A mutation was observed in proviral DNA recovered from other organs. Remarkably, HIV replication persisted despite the inability of HIV to develop resistance to APOBEC3 in the absence of Vif. Our results provide novel insight into a highly specific subset of cells that potentially circumvent the action of APOBEC3; however our results also demonstrate the massive inactivation of CCR5-tropic HIV in the absence of Vif.

  17. Live Virus Smallpox Vaccine

    Science.gov (United States)

    ... A - Z Index SMALLPOX FACT SHEET The Live Virus Smallpox Vaccine The vaccinia virus is the "live ... it cannot cause smallpox. What is a "live virus" vaccine? A "live virus" vaccine is a vaccine ...

  18. Sequencing and rescuing a highly virulent classical swine fever virus: Chinese strain cF114 from a full-length cDNA clone

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The complete nucleotide sequence of classical swine fever virus (CSFV) strain cF114 (F114 strain propa- gated on PK-15 cells) was cloned by RT-PCR. The analyses of nucleotide and amino acids identity between cF114 and F114, Brescia, Alfort or C strain were 99.41%, 96.80%, 86.03%, 95.70% and 99.28%, 98.54%, 93.33%, 97.41% re- spectively. The cDNA fragments with correct sequence were ligated into a full-length cDNA and inserted into pMC18 plasmid (pMC12297). A full-length infectious viral RNA was synthesized by runoff transcription and transfected to PK15 cells. Viruses were recovered from transfected cells which wese titrated on PK-15 cells by endpoint dilution and indirect immunofluorescence with a CSFV-specific monoclonal antibody. The antigenicity and replication kinetics of the plasmid-derived virus (vM12297) were similar to the parental virus in vitro. The E01 or E2 gene was replaced with the genes from strain C and the pM/CE01 and pM/CE2 with chimeric full-length cDNA of cF114 were generated. The infectious viruses were obtained from pM/CE01 and pM/CE2. Both of the chimeric viruses can infect PK-15, SK- 6 and primary testicle cell of swine. The chimeric viruses can grow to a titer of 8×105 F-PFU/mL. These results are very important for understanding the genes related to the CSFV propagation and pathogenesis.

  19. Links between human LINE-1 retrotransposons and hepatitis virus-related hepatocellular carcinoma

    Science.gov (United States)

    Honda, Tomoyuki

    2016-05-01

    Hepatocellular carcinoma (HCC) accounts for approximately 80% of liver cancers, the third most frequent cause of cancer mortality. The most prevalent risk factors for HCC are infections by hepatitis B or hepatitis C virus. Findings suggest that hepatitis virus-related HCC might be a cancer in which LINE-1 retrotransposons, often termed L1, activity plays a potential role. Firstly, hepatitis viruses can suppress host defense factors that also control L1 mobilization. Secondly, many recent studies also have indicated that hypomethylation of L1 affects the prognosis of HCC patients. Thirdly, endogenous L1 retrotransposition was demonstrated to activate oncogenic pathways in HCC. Fourthly, several L1 chimeric transcripts with host or viral genes are found in hepatitis virus-related HCC. Such lines of evidence suggest a linkage between L1 retrotransposons and hepatitis virus-related HCC. Here, I briefly summarize current understandings of the association between hepatitis virus-related HCC and L1. Then, I discuss potential mechanisms of how hepatitis viruses drive the development of HCC via L1 retrotransposons. An increased understanding of the contribution of L1 to hepatitis virus-related HCC may provide unique insights related to the development of novel therapeutics for this disease.

  20. Links between Human LINE-1 Retrotransposons and Hepatitis Virus-Related Hepatocellular Carcinoma

    Science.gov (United States)

    Honda, Tomoyuki

    2016-01-01

    Hepatocellular carcinoma (HCC) accounts for approximately 80% of liver cancers, the third most frequent cause of cancer mortality. The most prevalent risk factors for HCC are infections by hepatitis B or hepatitis C virus. Findings suggest that hepatitis virus-related HCC might be a cancer in which LINE-1 retrotransposon, often termed L1, activity plays a potential role. Firstly, hepatitis viruses can suppress host defense factors that also control L1 mobilization. Secondly, many recent studies also have indicated that hypomethylation of L1 affects the prognosis of HCC patients. Thirdly, endogenous L1 retrotransposition was demonstrated to activate oncogenic pathways in HCC. Fourthly, several L1 chimeric transcripts with host or viral genes are found in hepatitis virus-related HCC. Such lines of evidence suggest a linkage between L1 retrotransposons and hepatitis virus-related HCC. Here, I briefly summarize current understandings of the association between hepatitis virus-related HCC and L1. Then, I discuss potential mechanisms of how hepatitis viruses drive the development of HCC via L1 retrotransposons. An increased understanding of the contribution of L1 to hepatitis virus-related HCC may provide unique insights related to the development of novel therapeutics for this disease.

  1. Chimeric Mouse model to track the migration of bone marrow derived cells in glioblastoma following anti-angiogenic treatments.

    Science.gov (United States)

    Achyut, B R; Shankar, Adarsh; Iskander, A S M; Ara, Roxan; Knight, Robert A; Scicli, Alfonso G; Arbab, Ali S

    2016-03-01

    Bone marrow derived cells (BMDCs) have been shown to contribute in the tumor development. In vivo animal models to investigate the role of BMDCs in tumor development are poorly explored. We established a novel chimeric mouse model using as low as 5 × 10(6) GFP+ BM cells in athymic nude mice, which resulted in >70% engraftment within 14 d. In addition, chimera was established in NOD-SCID mice, which displayed >70% with in 28 d. Since anti-angiogenic therapies (AAT) were used as an adjuvant against VEGF-VEGFR pathway to normalize blood vessels in glioblastoma (GBM), which resulted into marked hypoxia and recruited BMDCs to the tumor microenvironment (TME). We exploited chimeric mice in athymic nude background to develop orthotopic U251 tumor and tested receptor tyrosine kinase inhibitors and CXCR4 antagonist against GBM. We were able to track GFP+ BMDCs in the tumor brain using highly sensitive multispectral optical imaging instrument. Increased tumor growth associated with the infiltration of GFP+ BMDCs acquiring suppressive myeloid and endothelial phenotypes was seen in TME following treatments. Immunofluorescence study showed GFP+ cells accumulated at the site of VEGF, SDF1 and PDGF expression, and at the periphery of the tumors following treatments. In conclusion, we developed a preclinical chimeric model of GBM and phenotypes of tumor infiltrated BMDCs were investigated in context of AATs. Chimeric mouse model could be used to study detailed cellular and molecular mechanisms of interaction of BMDCs and TME in cancer. PMID:26797476

  2. Fluctuations between multiple EF-G-induced chimeric tRNA states during translocation on the ribosome

    Science.gov (United States)

    Adio, Sarah; Senyushkina, Tamara; Peske, Frank; Fischer, Niels; Wintermeyer, Wolfgang; Rodnina, Marina V.

    2015-06-01

    The coupled translocation of transfer RNA and messenger RNA through the ribosome entails large-scale structural rearrangements, including step-wise movements of the tRNAs. Recent structural work has visualized intermediates of translocation induced by elongation factor G (EF-G) with tRNAs trapped in chimeric states with respect to 30S and 50S ribosomal subunits. The functional role of the chimeric states is not known. Here we follow the formation of translocation intermediates by single-molecule fluorescence resonance energy transfer. Using EF-G mutants, a non-hydrolysable GTP analogue, and fusidic acid, we interfere with either translocation or EF-G release from the ribosome and identify several rapidly interconverting chimeric tRNA states on the reaction pathway. EF-G engagement prevents backward transitions early in translocation and increases the fraction of ribosomes that rapidly fluctuate between hybrid, chimeric and posttranslocation states. Thus, the engagement of EF-G alters the energetics of translocation towards a flat energy landscape, thereby promoting forward tRNA movement.

  3. The construction of chimeric T-Cell receptor with spacer base of modeling study of VHH and MUC1 interaction.

    Science.gov (United States)

    Pirooznia, Nazanin; Hasannia, Sadegh; Taghdir, Majid; Rahbarizadeh, Fatemeh; Eskandani, Morteza

    2011-01-01

    Adaptive cell immunotherapy with the use of chimeric receptors leads to the best and most specific response against tumors. Chimeric receptors consist of a signaling fragment, extracellular spacer, costimulating domain, and an antibody. Antibodies cause immunogenicity; therefore, VHH is a good replacement for ScFv in chimeric receptors. Since peptide sequences have an influence on chimeric receptors, the effect of peptide domains on each other's conformation were investigated. CD3Zeta, CD28, VHH and CD8α, and FcgIIα are used as signaling moieties, costimulating domain, antibody, and spacers, respectively. To investigate the influence of the ligation of spacers on the conformational structure of VHH, models of VHH were constructed. Molecular dynamics simulation was run to study the influence of the presence of spacers on the conformational changes in the binding sites of VHH. Root mean square deviation and root mean square fluctuation of critical segments in the binding site showed no noticeable differences with those in the native VHH. Results from molecular docking revealed that the presence of spacer FcgIIα causes an increasing effect on VHH with MUC1 interaction. Each of the constructs was transformed into the Jurkat E6.1. Expression analysis and evaluation of their functions were examined. The results showed good expression and function. PMID:21869862

  4. The Construction of Chimeric T-Cell Receptor with Spacer Base of Modeling Study of VHH and MUC1 Interaction

    Directory of Open Access Journals (Sweden)

    Nazanin Pirooznia

    2011-01-01

    Full Text Available Adaptive cell immunotherapy with the use of chimeric receptors leads to the best and most specific response against tumors. Chimeric receptors consist of a signaling fragment, extracellular spacer, costimulating domain, and an antibody. Antibodies cause immunogenicity; therefore, VHH is a good replacement for ScFv in chimeric receptors. Since peptide sequences have an influence on chimeric receptors, the effect of peptide domains on each other's conformation were investigated. CD3Zeta, CD28, VHH and CD8α, and FcgIIα are used as signaling moieties, costimulating domain, antibody, and spacers, respectively. To investigate the influence of the ligation of spacers on the conformational structure of VHH, models of VHH were constructed. Molecular dynamics simulation was run to study the influence of the presence of spacers on the conformational changes in the binding sites of VHH. Root mean square deviation and root mean square fluctuation of critical segments in the binding site showed no noticeable differences with those in the native VHH. Results from molecular docking revealed that the presence of spacer FcgIIα causes an increasing effect on VHH with MUC1 interaction. Each of the constructs was transformed into the Jurkat E6.1. Expression analysis and evaluation of their functions were examined. The results showed good expression and function.

  5. Chimerism 47,XY,+21/46,XX in a female infant with anencephaly and other congenital defects

    OpenAIRE

    Danielle R. Lucon; Luciene M. Zanchetta; Cavalcanti, Denise P.

    2006-01-01

    Chimerism is rare in humans and is usually discovered accidentally when a 46,XX and 46,XY karyotype is found in a same individual. We describe a malformed female infant with neural tube defect (NTD) and a 47,XY,+21[5]/46,XX[30] karyotype.

  6. Chimerism 47,XY,+21/46,XX in a female infant with anencephaly and other congenital defects

    Directory of Open Access Journals (Sweden)

    Danielle R. Lucon

    2006-01-01

    Full Text Available Chimerism is rare in humans and is usually discovered accidentally when a 46,XX and 46,XY karyotype is found in a same individual. We describe a malformed female infant with neural tube defect (NTD and a 47,XY,+21[5]/46,XX[30] karyotype.

  7. Targeting apoptosis to induce stable mixed hematopoietic chimerism and long-term allograft survival without myelosuppressive conditioning in mice.

    Science.gov (United States)

    Cippà, Pietro E; Gabriel, Sarah S; Chen, Jin; Bardwell, Philip D; Bushell, Andrew; Guimezanes, Annick; Kraus, Anna K; Wekerle, Thomas; Wüthrich, Rudolf P; Fehr, Thomas

    2013-08-29

    Induction of mixed hematopoietic chimerism results in donor-specific immunological tolerance by apoptosis-mediated deletion of donor-reactive lymphocytes. A broad clinical application of this approach is currently hampered by limited predictability and toxicity of the available conditioning protocols. We developed a new therapeutic approach to induce mixed chimerism and tolerance by a direct pharmacological modulation of the intrinsic apoptosis pathway in peripheral T cells. The proapoptotic small-molecule Bcl-2 inhibitor ABT-737 promoted mixed chimerism induction and reversed the antitolerogenic effect of calcineurin inhibitors by boosting the critical role of the proapoptotic Bcl-2 factor Bim. A short conditioning protocol with ABT-737 in combination with costimulation blockade and low-dose cyclosporine A resulted in a complete deletion of peripheral donor-reactive lymphocytes and was sufficient to induce mixed chimerism and robust systemic tolerance across full major histocompatibility complex barriers, without myelosuppression and by using moderate doses of bone marrow cells. Thus, immunological tolerance can be achieved by direct modulation of the intrinsic apoptosis pathway in peripheral lymphocytes-a new approach to translate immunological tolerance into clinically applicable protocols. PMID:23869083

  8. Performance Assessment of Four Chimeric Trypanosoma cruzi Antigens Based on Antigen-Antibody Detection for Diagnosis of Chronic Chagas Disease.

    Science.gov (United States)

    Santos, Fred Luciano Neves; Celedon, Paola Alejandra Fiorani; Zanchin, Nilson Ivo Tonin; Brasil, Tatiana de Arruda Campos; Foti, Leonardo; Souza, Wayner Vieira de; Silva, Edmilson Domingos; Gomes, Yara de Miranda; Krieger, Marco Aurélio

    2016-01-01

    The performance of serologic tests in chronic Chagas disease diagnosis largely depends on the type and quality of the antigen preparations that are used for detection of anti-Trypanosoma cruzi antibodies. Whole-cell T. cruzi extracts or recombinant proteins have shown variation in the performance and cross-reactivity. Synthetic chimeric proteins comprising fragments of repetitive amino acids of several different proteins have been shown to improve assay performances to detect Chagasic infections. Here, we describe the production of four chimeric T. cruzi proteins and the assessment of their performance for diagnostic purposes. Circular Dichroism spectra indicated the absence of well-defined secondary structures, while polydispersity evaluated by Dynamic Light Scattering revealed only minor aggregates in 50 mM carbonate-bicarbonate (pH 9.6), demonstrating that it is an appropriate buffering system for sensitizing microplates. Serum samples from T. cruzi-infected and non-infected individuals were used to assess the performance of these antigens for detecting antibodies against T. cruzi, using both enzyme-linked immunosorbent assay and a liquid bead array platform. Performance parameters (AUC, sensitivity, specificity, accuracy and J index) showed high diagnostic accuracy for all chimeric proteins for detection of specific anti-T. cruzi antibodies and differentiated seropositive individuals from those who were seronegative. Our data suggest that these four chimeric proteins are eligible for phase II studies. PMID:27517281

  9. Entrée du virus de l'hépatite C et transmission de cellule à cellule : implications pour le cycle viral et le traitement antiviral

    OpenAIRE

    Xiao, Fei

    2014-01-01

    Hepatitis C virus (HCV) poses a threat to global health with infecting about 170 million people. Current therapies cannot cure all the patients infected with HCV and have obvious side effects. In the first part of my thesis, we uncovered combinations of direct-acting antivirals (DAAs) and entry inhibitors caracterized by a synergistic effect in prevention and treatment of HCV infection using HCV cell culture models and human liver chimeric uPA-SCID mice, thereby providing a new strategy to co...

  10. The kissing-loop motif is a preferred site of 5' leader recombination during replication of SL3-3 murine leukemia viruses in mice

    DEFF Research Database (Denmark)

    Lund, Anders Henrik; Mikkelsen, J G; Schmidt, J; Duch, M; Pedersen, F S

    1999-01-01

    exogenous input virus and endogenous MLV-like sequences within the 5' leader region. Evidence of recombination within the region studied was found in 14 of 52 tumors analyzed. Sequence analysis of a approximately 330-bp fragment of 44 chimeric proviruses, encompassing the U5, the primer binding site, and...... loop, presumably via a role in RNA dimer formation, constitutes a hot spot for reverse transcriptase-mediated recombination in MLV....

  11. Cell-to-cell movement of Alfalfa mosaic virus can be mediated by the movement proteins of Ilar-, bromo-, cucumo-, tobamo- and comoviruses and does not require virion formation.

    Science.gov (United States)

    Sánchez-Navarro, Jesús A; Carmen Herranz, María; Pallás, Vicente

    2006-03-01

    RNA 3 of Alfalfa mosaic virus (AMV) encodes the movement protein (MP) and coat protein (CP). Chimeric RNA 3 with the AMV MP gene replaced by the corresponding MP gene of Prunus necrotic ringspot virus, Brome mosaic virus, Cucumber mosaic virus or Cowpea mosaic virus efficiently moved from cell-to-cell only when the expressed MP was extended at its C-terminus with the C-terminal 44 amino acids of AMV MP. MP of Tobacco mosaic virus supported the movement of the chimeric RNA 3 whether or not the MP was extended with the C-terminal AMV MP sequence. The replacement of the CP gene in RNA 3 by a mutant gene encoding a CP defective in virion formation did not affect cell-to-cell transport of the chimera's with a functional MP. A GST pull-down technique was used to demonstrate for the first time that the C-terminal 44 amino acids of the MP of a virus belonging to the family Bromoviridae interact specifically with AMV virus particles. Together, these results demonstrate that AMV RNA 3 can be transported from cell-to-cell by both tubule-forming and non-tubule-forming MPs if a specific MP-CP interaction occurs. PMID:16316673

  12. CCR5 inhibitors: Emerging promising HIV therapeutic strategy

    Directory of Open Access Journals (Sweden)

    Surya Rao Padmasri

    2009-01-01

    Full Text Available Though potent anti-HIV therapy has spectacularly reduced the morbidity and mortality of human immunodeficiency virus (HIV-1 infection in the advanced countries, it continues to be associated with substantial toxicity, drug-drug interactions, difficulties in adherence, and abnormal cost. As a result, better effective, safe antiretroviral drugs and treatment strategies keep on to be pursued. In this process, CCR5 (chemokine receptor 5 inhibitors are a new class of antiretroviral drug used in the treatment of HIV. They are designed to prevent HIV infection of CD4 T-cells by blocking the CCR5. When the CCR5 receptor is unavailable, ′R5-tropic′ HIV (the variant of the virus that is common in earlier HIV infection cannot engage with a CD4 T-cell to infect the cell. In August 2007, the FDA approved the first chemokine (C-C motif CCR5 inhibitor, maraviroc, for treatment-experienced patients infected with R5-using virus. Studies from different cohort in regions, affected by clad B HIV-1, demonstrate that 81-88% of HIV-1 variants in treatment naïve patients are CCR5 tropic and that virtually all the remaining variants are dual/mixed tropic i.e., are able to utilize both CCR5 and CXCR4 coreceptors. In treatment experienced patients, 49−78% of the variants are purely CCR5 tropic, 22−48% are dual/mixed tropic, and 2-5% exclusively utilize CXCR4. A 32 bp deletion in the CCR5 gene, which results in a frame shift and truncation of the normal CCR5 protein, was identified in a few persons who had remained uninfected after exposure to CCR5 tropic HIV-1 virus. This allele is common in white of European origin, with prevalence near to 10%, but is absent among East Asian, American Indian, Tamil Indian, and African ethnic groups. HIV-infected individuals, who are heterozygous for CCR5 delta 32, have slower rates of disease progression. The currently available data supports the continuation of the development of CCR5 antagonists in different settings related

  13. Computer Viruses. Technology Update.

    Science.gov (United States)

    Ponder, Tim, Comp.; Ropog, Marty, Comp.; Keating, Joseph, Comp.

    This document provides general information on computer viruses, how to help protect a computer network from them, measures to take if a computer becomes infected. Highlights include the origins of computer viruses; virus contraction; a description of some common virus types (File Virus, Boot Sector/Partition Table Viruses, Trojan Horses, and…

  14. Development of an infectious surrogate hepatitis C virus based on a recombinant vesicular stomatitis virus expressing hepatitis C virus envelope glycoproteins and green fluorescent protein.

    Science.gov (United States)

    Okuma, Kazu; Fukagawa, Koji; Tateyama, Seiji; Kohma, Takuya; Mochida, Keiko; Hiyoshi, Masateru; Takahama, Youichi; Hamaguchi, Yukio; Hirose, Kunitaka; Buonocore, Linda; Rose, John K; Mizuochi, Toshiaki; Hamaguchi, Isao

    2015-01-01

    To develop surrogate viruses for hepatitis C virus (HCV), we previously produced recombinant vesicular stomatitis viruses (rVSVs) lacking glycoprotein G but instead expressing chimeric HCV E1/E2 fused to G. These rVSVs were not infectious in HCV-susceptible hepatoma cells. In this study, to develop an infectious surrogate HCV based on an rVSV (vesicular stomatitis virus [VSV]/HCV), we generated a novel rVSV encoding the native E1/E2 (H77 strain) and green fluorescent protein (GFP) instead of G. Here, we showed that this VSV/HCV efficiently infected human hepatoma cells, including Huh7 human hepatoma cells, expressed GFP in these cells, and propagated, but did not do so in nonsusceptible BHK-21 cells. The infectivity of VSV/HCV, measured as the number of foci of GFP-positive cells, was specifically reduced by the addition of chimpanzee anti-HCV serum, anti-E2 antibody, or anti-CD81 antibody to the cultures. When sera obtained from HCV-infected or uninfected patients were added, infection was selectively inhibited only by the sera of HCV-infected patients. These data together suggest that this infectious GFP-expressing VSV/HCV could be a useful tool for studying the mechanisms of HCV entry into cells and for assessing potential inhibitors of viral entry, including neutralizing antibodies. PMID:25672345

  15. Chimeric HIV-1 envelope glycoproteins with potent intrinsic granulocyte-macrophage colony-stimulating factor (GM-CSF activity.

    Directory of Open Access Journals (Sweden)

    Gözde Isik

    Full Text Available HIV-1 acquisition can be prevented by broadly neutralizing antibodies (BrNAbs that target the envelope glycoprotein complex (Env. An ideal vaccine should therefore be able to induce BrNAbs that can provide immunity over a prolonged period of time, but the low intrinsic immunogenicity of HIV-1 Env makes the elicitation of such BrNAbs challenging. Co-stimulatory molecules can increase the immunogenicity of Env and we have engineered a soluble chimeric Env trimer with an embedded granulocyte-macrophage colony-stimulating factor (GM-CSF domain. This chimeric molecule induced enhanced B and helper T cell responses in mice compared to Env without GM-CSF. We studied whether we could optimize the activity of the embedded GM-CSF as well as the antigenic structure of the Env component of the chimeric molecule. We assessed the effect of truncating GM-CSF, removing glycosylation-sites in GM-CSF, and adjusting the linker length between GM-CSF and Env. One of our designed Env(GM-CSF chimeras improved GM-CSF-dependent cell proliferation by 6-fold, reaching the same activity as soluble recombinant GM-CSF. In addition, we incorporated GM-CSF into a cleavable Env trimer and found that insertion of GM-CSF did not compromise Env cleavage, while Env cleavage did not compromise GM-CSF activity. Importantly, these optimized Env(GM-CSF proteins were able to differentiate human monocytes into cells with a macrophage-like phenotype. Chimeric Env(GM-CSF should be useful for improving humoral immunity against HIV-1 and these studies should inform the design of other chimeric proteins.

  16. MHC-mismatched mixed chimerism augments thymic regulatory T-cell production and prevents relapse of EAE in mice.

    Science.gov (United States)

    Wu, Limin; Li, Nainong; Zhang, Mingfeng; Xue, Sheng-Li; Cassady, Kaniel; Lin, Qing; Riggs, Arthur D; Zeng, Defu

    2015-12-29

    Multiple sclerosis (MS) is an autoimmune inflammatory disease of the central nervous system with demyelination, axon damage, and paralysis. Induction of mixed chimerism with allogeneic donors has been shown to not cause graft-versus-host disease (GVHD) in animal models and humans. We have reported that induction of MHC-mismatched mixed chimerism can cure autoimmunity in autoimmune NOD mice, but this approach has not yet been tested in animal models of MS, such as experimental autoimmune encephalomyelitis (EAE). Here, we report that MHC-mismatched mixed chimerism with C57BL/6 (H-2(b)) donor in SJL/J (H-2(s)) EAE recipients eliminates clinical symptoms and prevents relapse. This cure is demonstrated by not only disappearance of clinical signs but also reversal of autoimmunity; elimination of infiltrating T, B, and macrophage cells in the spinal cord; and regeneration of myelin sheath. The reversal of autoimmunity is associated with a marked reduction of autoreactivity of CD4(+) T cells and significant increase in the percentage of Foxp3(+) Treg among host-type CD4(+) T cells in the spleen and lymph nodes. The latter is associated with a marked reduction of the percentage of host-type CD4(+)CD8(+) thymocytes and an increase of Treg percentage among the CD4(+)CD8(+) and CD4(+)CD8(-) thymocytes. Thymectomy leads to loss of prevention of EAE relapse by induction of mixed chimerism, although there is a dramatic expansion of host-type Treg cells in the lymph nodes. These results indicate that induction of MHC-mismatched mixed chimerism can restore thymic negative selection of autoreactive CD4(+) T cells, augment production of Foxp3(+) Treg, and cure EAE. PMID:26647186

  17. Chimeric Antigen Receptor-Engineered T Cells for Immunotherapy of Cancer

    Directory of Open Access Journals (Sweden)

    Marc Cartellieri

    2010-01-01

    Full Text Available CD4+ and CD8+ T lymphocytes are powerful components of adaptive immunity, which essentially contribute to the elimination of tumors. Due to their cytotoxic capacity, T cells emerged as attractive candidates for specific immunotherapy of cancer. A promising approach is the genetic modification of T cells with chimeric antigen receptors (CARs. First generation CARs consist of a binding moiety specifically recognizing a tumor cell surface antigen and a lymphocyte activating signaling chain. The CAR-mediated recognition induces cytokine production and tumor-directed cytotoxicity of T cells. Second and third generation CARs include signal sequences from various costimulatory molecules resulting in enhanced T-cell persistence and sustained antitumor reaction. Clinical trials revealed that the adoptive transfer of T cells engineered with first generation CARs represents a feasible concept for the induction of clinical responses in some tumor patients. However, further improvement is required, which may be achieved by second or third generation CAR-engrafted T cells.

  18. Detecting chimeric 5′/3′UTRs with cross-chromosomal splicing by bioinformatics

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhihua; ZHANG Yong; SHI Baochen; DENG Wei; ZHAO Yi; CHEN Runsheng

    2004-01-01

    The 5′/3′ UTRs of mRNA are crucial in translational regulation, and several serious diseases are believed to be associated with abnormal splicing of these parts of the mRNA sequence. In this work a novel method which uses sequence alignment database searching for detecting chimeric 5′3′ UTRs with cross-chromosomal splicing is reported. Eight highly credible instances of cross-chromosomal splicing have been found using this method, representing additional confirmation of the existence of cross-chromosomal splicing events provided by bioinformatics tools. Since no conserved motif has been found in any of the eight instances, and at the same time current prediction algorithms produce only trivial secondary structures at the "splicing sites", it is not possible to identify any specific signal leading to the splicing.

  19. Case of 46,XX/47,XY, +21 chimerism in a newborn infant with ambiguous genitalia

    Energy Technology Data Exchange (ETDEWEB)

    Sawai, Tomoko; Yoshimoto, Masaaki; Kinoshita, Ei-ichi; Baba, Tsuneyoshi; Matsumoto, Tadashi; Tsuji, Yoshiro, Niikawa, Norio [Nagasaki Univ. School of Medicine, Nagasaki (Japan); Fukuda, Shinpei [Ohmura Municipal Hospital, Ohmura (Japan); Harada, Naoki [Kyushu Medical Science, Nagasaki (Japan)

    1994-02-15

    The authors describe the whole-body chimerism in a newborn infant with small phallus, pseudo-vaginal perineal hypospadias, and a bifid scrotum containing gonads. The human testis determining factor gene (SRY) was detected by PCR amplification. GTG-banding chromosome analysis in peripheral blood lymphocytes and cultured fibroblasts derived from right cubital skin showed a 46,XX/47,XY, +21 karyotype. Their ratios in each cell line were 294:5 and 178:7, respectively. QFQ-banding chromosome analysis documented 3 heteromorphic satellites on trisomic chromsomes 21 in the 47,XY,+21 cell line and a homozygous satellite pattern in the 46,XX cell line. Heteromorphic patterns of chromsomes 4, 13, 14, and 22 were also different between the two cell lines. To our knowledge, such disomy/trisomy chimeras have not been described previously. 10 refs., 3 figs.

  20. Giant trochanteric pressure sore: Use of a pedicled chimeric perforator flap for cover

    Directory of Open Access Journals (Sweden)

    Mehrotra Sandeep

    2009-01-01

    Full Text Available Pressure sores are increasing in frequency commensurate with an ageing population with multi-system disorders and trauma. Numerous classic options are described for providing stable wound cover. With the burgeoning knowledge on perforator anatomy, recent approaches focus on the use of perforator-based flaps in bedsore surgery. A giant neglected trochanteric pressure sore in a paraplegic is presented. Since conventional options of reconstruction appeared remote, the massive ulcer was successfully managed by a chimeric perforator-based flap. The combined muscle and fasciocutaneous flaps were raised as separate paddles based on the anterolateral thigh perforator branches and provided stable cover without complications. Perforators allow versatility in managing complex wounds without compromising on established principles.

  1. Improving therapy of chronic lymphocytic leukemia with chimeric antigen receptor T cells.

    Science.gov (United States)

    Fraietta, Joseph A; Schwab, Robert D; Maus, Marcela V

    2016-04-01

    Adoptive cell immunotherapy for the treatment of chronic lymphocytic leukemia (CLL) has heralded a new era of synthetic biology. The infusion of genetically engineered, autologous chimeric antigen receptor (CAR) T cells directed against CD19 expressed by normal and malignant B cells represents a novel approach to cancer therapy. The results of recent clinical trials of CAR T cells in relapsed and refractory CLL have demonstrated long-term disease-free remissions, underscoring the power of harnessing and redirecting the immune system against cancer. This review will briefly summarize T-cell therapies in development for CLL disease. We discuss the role of T-cell function and phenotype, T-cell culture optimization, CAR design, and approaches to potentiate the survival and anti-tumor effects of infused lymphocytes. Future efforts will focus on improving the efficacy of CAR T cells for the treatment of CLL and incorporating adoptive cell immunotherapy into standard medical management of CLL. PMID:27040708

  2. Discovery of mitochondrial chimeric-gene associated with cytoplasmic male sterility of HL-rice

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The mitochondrial genome libraries of HL-type sterile line(A) and maintainer line(B) have been constructed.Mitochondrial gene, atp6, was used to screen libraries, due to the different Southern and Northern blot results between sterile and maintainer line. Sequencing analysis of positive clones proved that there were two copies of atp6 gene in sterile line and only one in maintainer line. One copy of atpt6 in sterile line was same to that in maintainer line; the other showed different flanking sequence from the 49th nucleotide downstream of the termination codon of atp6 gene. A new chimeric gene, orfH79, was found in the region. OrfH79 had homology to mitochondrial gene coxⅡ and orfl07, and was special to HL-sterile cytoplasm.``

  3. An amino-terminal segment of hantavirus nucleocapsid protein presented on hepatitis B virus core particles induces a strong and highly cross-reactive antibody response in mice

    International Nuclear Information System (INIS)

    Previously, we have demonstrated that hepatitis B virus (HBV) core particles tolerate the insertion of the amino-terminal 120 amino acids (aa) of the Puumala hantavirus nucleocapsid (N) protein. Here, we demonstrate that the insertion of 120 amino-terminal aa of N proteins from highly virulent Dobrava and Hantaan hantaviruses allows the formation of chimeric core particles. These particles expose the inserted foreign protein segments, at least in part, on their surface. Analysis by electron cryomicroscopy of chimeric particles harbouring the Puumala virus (PUUV) N segment revealed 90% T = 3 and 10% T = 4 shells. A map computed from T = 3 shells shows additional density splaying out from the tips of the spikes producing the effect of an extra shell of density at an outer radius compared with wild-type shells. The inserted Puumala virus N protein segment is flexibly linked to the core spikes and only partially icosahedrally ordered. Immunisation of mice of two different haplotypes (BALB/c and C57BL/6) with chimeric core particles induces a high-titered and highly cross-reactive N-specific antibody response in both mice strains

  4. Chimeric External Control to Quantify Cell Free DNA in Plasma Samples by Real Time PCR

    Science.gov (United States)

    Eini, Maryam; Behzad-Behbahani, Abbas; Takhshid, Mohammad Ali; Ramezani, Amin; Rafiei Dehbidi, Gholam Reza; Okhovat, Mohammad Ali; Farhadi, Ali; Alavi, Parniyan

    2016-01-01

    Background: DNA isolation procedure can significantly influence the quantification of DNA by real time PCR specially when cell free DNA (cfDNA) is the subject. To assess the extraction efficiency, linearity of the extraction yield, presence of co-purified inhibitors and to avoid problems with fragment size relevant to cfDNA, development of appropriate External DNA Control (EDC) is challenging. Using non-human chimeric nucleotide sequences, an EDC was developed for standardization of qPCR for monitoring stability of cfDNA concentration in blood samples over time. Methods: A0 DNA fragment of 167 bp chimeric sequence of parvovirus B19 and pBHA designated as EDC fragment was designed. To determine the impact of different factors during DNA extraction processing on quantification of cfDNA, blood samples were collected from normal subjects and divided into aliquots with and without specific treatment. In time intervals, the plasma samples were isolated. The amplicon of 167 bp EDC fragment in final concentration of 1.1 pg/500 μl was added to each plasma sample and total DNA was extracted by an in house method. Relative and absolute quantification real time PCR was performed to quantify both EDC fragment and cfDNA in extracted samples. Results: Comparison of real time PCR threshold cycle (Ct) for cfDNA fragment in tubes with and without specific treatment indicated a decrease in untreated tubes. In contrast, the threshold cycle was constant for EDC fragment in treated and untreated tubes, indicating the difference in Ct values of the cfDNA is because of specific treatments that were made on them. Conclusions: Spiking of DNA fragment size relevant to cfDNA into the plasma sample can be useful to minimize the bias due to sample preparation and extraction processing. Therefore, it is highly recommended that standard external DNA control be employed for the extraction and quantification of cfDNA for accurate data analysis.

  5. Synthetic metabolic engineering-a novel, simple technology for designing a chimeric metabolic pathway

    Directory of Open Access Journals (Sweden)

    Ye Xiaoting

    2012-09-01

    Full Text Available Abstract Background The integration of biotechnology into chemical manufacturing has been recognized as a key technology to build a sustainable society. However, the practical applications of biocatalytic chemical conversions are often restricted due to their complexities involving the unpredictability of product yield and the troublesome controls in fermentation processes. One of the possible strategies to overcome these limitations is to eliminate the use of living microorganisms and to use only enzymes involved in the metabolic pathway. Use of recombinant mesophiles producing thermophilic enzymes at high temperature results in denaturation of indigenous proteins and elimination of undesired side reactions; consequently, highly selective and stable biocatalytic modules can be readily prepared. By rationally combining those modules together, artificial synthetic pathways specialized for chemical manufacturing could be designed and constructed. Results A chimeric Embden-Meyerhof (EM pathway with balanced consumption and regeneration of ATP and ADP was constructed by using nine recombinant E. coli strains overproducing either one of the seven glycolytic enzymes of Thermus thermophilus, the cofactor-independent phosphoglycerate mutase of Pyrococcus horikoshii, or the non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase of Thermococcus kodakarensis. By coupling this pathway with the Thermus malate/lactate dehydrogenase, a stoichiometric amount of lactate was produced from glucose with an overall ATP turnover number of 31. Conclusions In this study, a novel and simple technology for flexible design of a bespoke metabolic pathway was developed. The concept has been testified via a non-ATP-forming chimeric EM pathway. We designated this technology as “synthetic metabolic engineering”. Our technology is, in principle, applicable to all thermophilic enzymes as long as they can be functionally expressed in the host, and thus would be

  6. Fibrinogen interaction of CHO cells expressing chimeric αIIb/αvβ3 integrin

    Institute of Scientific and Technical Information of China (English)

    Juan-juan CHEN; Xiao-yu SU; Xiao-dong XI; Li-ping LIN; Jian DING; He LU

    2008-01-01

    Aim: The molecular mechanisms of the affinity regulation of αvβ3 integrin are important in tumor development, wound repairing, and angiogenesis. It has been established that the cytoplasmic domains of αvβ3 integrin play an important role in integrin-ligand affinity regulation. However, the relationship of structure-func-tion within these domains remains unclear. Methods: The extracellular and trans-membrane domain of αⅡb was fused to the αv integrin cytoplasmic domain, and the chimeric α subunit was coexpressed in Chinese hamster ovary (CHO) cells with the wild-type β3 subunit or with 3 mutant 133 sequences bearing truncations at the positions of T741, Y747, and F754, respectively. The CHO cells expressing these recombinant integrins were tested for soluble fibrinogen binding and the cell adhesion and spreading on immobilized fibrinogen. Results: All 4 types of integrins bound soluble fibrinogen in the absence of agonist stimulation, and only the cells expressing the chimeric α subunit with the wild-type β3 subunit, but not those with truncated β3, could adhere to and spread on immobilized fibrinogen. Conclusion: The substitution αⅡb at the cytoplasmic domain with the ctv cyto-plasmic sequence rendered the extracellular αⅡbβ3 a constitutively activated con-formation for ligands without the need of "inside-out" signals. Our results also indicated that the COOH-terminal sequence of β3 might play a key role in integrin αⅡb/αvβ3-mediated cell adhesion and spreading on immobilized fibrinogen. The cells expressing αⅡb/αvβ3 have enormous potential for facilitating drug screen-ing for antagonists either to αvβ3 intracellular interactions or to αⅡbβ3 receptor functions.

  7. Enhancement by dimethyl myleran of donor type chimerism in murine recipients of bone marrow allografts

    International Nuclear Information System (INIS)

    A major problem in using murine models for studies of bone marrow allograft rejection in leukemia patients is the narrow margin in which graft rejection can be analyzed. In mice irradiated with greater than 9 Gy total body irradiation (TBI) rejection is minimal, whereas after administration of 8 Gy TBI, which spares a significant number of clonable T cells, a substantial frequency of host stem cells can also be detected. In current murine models, unlike in humans, bone marrow allograft rejection is generally associated with full autologous hematopoietic reconstitution. In the present study, we investigated the effect of the myeloablative drug dimethyl myleran (DMM) on chimerism status following transplantation of T cell-depleted allogenic bone marrow (using C57BL/6 donors and C3H/HeJ recipients, conditioned with 8 Gy TBI). Donor type chimerism 1 to 2 months post-transplant of 1 to 3 x 10(6) bone marrow cells was markedly enhanced by using DMM one day after TBI and prior to transplantation. Conditioning with cyclophosphamide instead of DMM, in combination with 8 Gy TBI, did not enhance engraftment of donor type cells. Artificial reconstitution of T cells, after conditioning with TBI plus DMM, by adding mature thymocytes, or presensitization with irradiated donor type spleen cells 1 week before TBI and DMM, led to strong graft rejection and consequently to severe anemia. The anti-donor responses in these models were proportional to the number of added T cells and to the number of cells used for presensitization, and they could be neutralized by increasing the bone marrow inoculum

  8. Enhanced protective efficacy of a chimeric form of the schistosomiasis vaccine antigen Sm-TSP-2.

    Directory of Open Access Journals (Sweden)

    Mark S Pearson

    Full Text Available The large extracellular loop of the Schistosoma mansoni tetraspanin, Sm-TSP-2, when fused to a thioredoxin partner and formulated with Freund's adjuvants, has been shown to be an efficacious vaccine against murine schistosomiasis. Moreover, Sm-TSP-2 is uniquely recognised by IgG(1 and IgG(3 from putatively resistant individuals resident in S. mansoni endemic areas in Brazil. In the present study, we expressed Sm-TSP-2 at high yield and in soluble form in E. coli without the need for a solubility enhancing fusion partner. We also expressed in E. coli a chimera called Sm-TSP-2/5B, which consisted of Sm-TSP-2 fused to the immunogenic 5B region of the hookworm aspartic protease and vaccine antigen, Na-APR-1. Sm-TSP-2 formulated with alum/CpG showed significant reductions in adult worm and liver egg burdens in two separate murine schistosomiasis challenge studies. Sm-TSP-2/5B afforded significantly greater protection than Sm-TSP-2 alone when both antigens were formulated with alum/CpG. The enhanced protection obtained with the chimeric fusion protein was associated with increased production of anti-Sm-TSP-2 antibodies and IL-4, IL-10 and IFN-γ from spleen cells of vaccinated animals. Sera from 666 individuals from Brazil who were infected with S. mansoni were screened for potentially deleterious IgE responses to Sm-TSP-2. Anti-Sm-TSP-2 IgE to this protein was not detected (also shown previously for Na-APR-1, suggesting that the chimeric antigen Sm-TSP-2/5B could be used to safely and effectively vaccinate people in areas where schistosomes and hookworms are endemic.

  9. Enhanced protective efficacy of a chimeric form of the schistosomiasis vaccine antigen Sm-TSP-2.

    Science.gov (United States)

    Pearson, Mark S; Pickering, Darren A; McSorley, Henry J; Bethony, Jeffrey M; Tribolet, Leon; Dougall, Annette M; Hotez, Peter J; Loukas, Alex

    2012-01-01

    The large extracellular loop of the Schistosoma mansoni tetraspanin, Sm-TSP-2, when fused to a thioredoxin partner and formulated with Freund's adjuvants, has been shown to be an efficacious vaccine against murine schistosomiasis. Moreover, Sm-TSP-2 is uniquely recognised by IgG(1) and IgG(3) from putatively resistant individuals resident in S. mansoni endemic areas in Brazil. In the present study, we expressed Sm-TSP-2 at high yield and in soluble form in E. coli without the need for a solubility enhancing fusion partner. We also expressed in E. coli a chimera called Sm-TSP-2/5B, which consisted of Sm-TSP-2 fused to the immunogenic 5B region of the hookworm aspartic protease and vaccine antigen, Na-APR-1. Sm-TSP-2 formulated with alum/CpG showed significant reductions in adult worm and liver egg burdens in two separate murine schistosomiasis challenge studies. Sm-TSP-2/5B afforded significantly greater protection than Sm-TSP-2 alone when both antigens were formulated with alum/CpG. The enhanced protection obtained with the chimeric fusion protein was associated with increased production of anti-Sm-TSP-2 antibodies and IL-4, IL-10 and IFN-γ from spleen cells of vaccinated animals. Sera from 666 individuals from Brazil who were infected with S. mansoni were screened for potentially deleterious IgE responses to Sm-TSP-2. Anti-Sm-TSP-2 IgE to this protein was not detected (also shown previously for Na-APR-1), suggesting that the chimeric antigen Sm-TSP-2/5B could be used to safely and effectively vaccinate people in areas where schistosomes and hookworms are endemic. PMID:22428079

  10. Comparing regional modeling (CHIMERE) and satellite observations of aerosols (PARASOL): Methodology and case study over Mexico

    Science.gov (United States)

    Stromatas, Stavros

    2010-05-01

    S. Stromatas (1), S. Turquety (1), H. Chepfer (1), L. Menut (1), B. Bessagnet (2), JC Pere (2), D. Tanré (3) . (1) Laboratoire de Météorologie Dynamique, CNRS/IPSL, École Polytechnique, 91128 Palaiseau Cedex, France, (2) INERIS, Institut National de l'Environnement Industriel et des Risques, Parc technologique ALATA, 60550 Verneuil en Halatte, FRANCE, (3) Laboratoire d'Optique Atmosphérique/CNRS Univ. des Sciences et Tech. de Lille, 59650 - Villeneuve d'Ascq, France. Atmospheric suspended particles (aerosols) have significant radiative and environmental impacts, affecting human health, visibility and climate. Therefore, they are regulated by air quality standards worldwide, and monitored by regional observation networks. Satellite observations vastly improve the horizontal and temporal coverage, providing daily distributions. Aerosols are currently estimated using aerosol optical depth (AOD) retrievals, a quantitative measure of the extinction of solar radiation by aerosol scattering and absorption between the point of observation and the top of the atmosphere. Even though remarkable progresses in aerosol modeling by chemistry-transport models (CTM) and measurement experiments have been made in recent years, there is still a significant divergence between the modeled and observed results. However, AOD retrievals from satellites remains a highly challenging task mostly because it depends on a variety of different parameters such as cloud contamination, surface reflectance contributions and a priori assumptions on aerosol types, each one of them incorporating its own difficulties. Therefore, comparisons between CTM and observations are often difficult to interpret. In this presentation, we will discuss comparisons between regional modeling (CHIMERE CTM) over Mexico and satellite observations obtained by the POLDER instrument embarked on PARASOL micro-satellite. After a comparison of the model AOD with the retrieved L2 AOD, we will present an alternative

  11. Translation efficiency determines differences in cellular infection among dengue virus type 2 strains

    International Nuclear Information System (INIS)

    We have investigated the molecular basis for differences in the ability of natural variants of dengue virus type 2 (DEN2) to replicate in primary human cells. The rates of virus binding, virus entry, input strand translation, and RNA stability of low-passage Thai and Nicaraguan and prototype DEN2 strains were compared. All strains exhibited equivalent binding, entry, and uncoating, and displayed comparable stability of positive strand viral RNA over time in primary cells. However, the low-passage Nicaraguan isolates were much less efficient in their ability to translate viral proteins. Sequence analysis of the full-length low-passage Nicaraguan and Thai viral genomes identified specific differences in the 3' untranslated region (3'UTR). Substitution of the different sequences into chimeric RNA reporter constructs demonstrated that the changes in the 3'UTR directly affected the efficiency of viral translation. Thus, differences in infectivity among closely related DEN2 strains correlate with efficiency of translation of input viral RNA

  12. The cytoplasmic tails of infectious bronchitis virus E and M proteins mediate their interaction

    International Nuclear Information System (INIS)

    Virus-like particle (VLP) formation by the coronavirus E and M proteins suggests that interactions between these proteins play a critical role in coronavirus assembly. We studied interactions between the infectious bronchitis virus (IBV) E and M proteins using in vivo crosslinking and VLP assembly assays. We show that IBV E and M can be crosslinked to each other in IBV-infected and transfected cells, indicating that they interact. The cytoplasmic tails of both proteins are important for this interaction. We also examined the ability of the mutant and chimeric E and M proteins to form VLPs. IBV M proteins that are missing portions of their cytoplasmic tails or transmembrane regions were not able to support VLP formation, regardless of their ability to be crosslinked to IBV E. Interactions between the E and M proteins and the membrane bilayer are likely to play an important role in VLP formation and virus budding

  13. Ebola Virus

    Directory of Open Access Journals (Sweden)

    Anusha Rangare Lakshman

    2015-09-01

    Full Text Available The disease Ebola takes its name from the Ebola River situated near a village in the Democratic Republic of Congo, where the disease first appeared in 1976. It is caused by a virus from the Filoviridae family (filovirus. The present outbreak of Ebola Virus Disease (EVD concerns four countries in West Africa, namely Guinea, Liberia, Sierra Leone and Nigeria till date. Further to widespread transmission of the disease, it has been declared as a Public Health Emergency of International Concern by the World Health Organisation on 8 August 2014. As of 4 August 2014, countries have reported 1,711 cases (1,070 confirmed, 436 probable, 205 suspect, including 932 deaths. This review paper enlightens about the awareness of Ebola virus and its preventive measures. [Archives Medical Review Journal 2015; 24(3.000: 296-305

  14. Improved humoral and cellular immune response against the gp120 V3 loop of HIV-1 following genetic immunization with a chimeric DNA vaccine encoding the V3 inserted into the hepatites B surface antigen

    DEFF Research Database (Denmark)

    Fomsgaard, A.; Nielsen, H.V.; Bryder, K.;

    1998-01-01

    The gp120-derived V3 loop of HIV-1 is involved in co-receptor interaction, it guides cell tropism, and contains an epitope for antibody neutralization. Thus, HIV-1 V3 is an attractive vaccine candidate. The V3 of the MN strain (MN V3) contains both B- and T-cell epitopes, including a known mouse H......-2d-restricted cytotoxic T lymphocyte (CTL) epitope. In an attempt to improve the immunogenicity of V3 in DNA vaccines, a plasmid expressing MN V3 as a fusion protein with the highly immunogenic middle (pre-S2+S) surface antigen of hepatitis B virus (HBsAg) was constructed. Epidermal inoculation by...... response and a uniform strong anti-HBs CTL response already 1 week p.i. in all mice. DNA vaccination with the chimeric MN V2/HBsAg plasmid elicited humoral responses against both viruses within 3-6 weeks which peaked at 6-12 weeks and remained stable for at least 25 weeks. In addition, specific CTL...

  15. Improved humoral and cellular immune responses against the gp120 V3 loop of HIV-1 following genetic immunization with a chimeric DNA vaccine encoding the V3 inserted into the hepatitis B surface antigen

    DEFF Research Database (Denmark)

    Fomsgaard, A; Nielsen, H V; Bryder, K;

    1998-01-01

    The gp120-derived V3 loop of HIV-1 is involved in co-receptor interaction, it guides cell tropism, and contains an epitope for antibody neutralization. Thus, HIV-1 V3 is an attractive vaccine candidate. The V3 of the MN strain (MN V3) contains both B- and T-cell epitopes, including a known mouse H......-2d-restricted cytotoxic T lymphocyte (CTL) epitope. In an attempt to improve the immunogenicity of V3 in DNA vaccines, a plasmid expressing MN V3 as a fusion protein with the highly immunogenic middle (pre-S2 + S) surface antigen of hepatitis B virus (HBsAg) was constructed. Epidermal inoculation by...... response and a uniform strong anti-HBs CTL response already 1 week p.i. in all mice. DNA vaccination with the chimeric MN V3/HBsAg plasmid elicited humoral responses against both viruses within 3-6 weeks which peaked at 6-12 weeks and remained stable for at least 25 weeks. In addition, specific CTL...

  16. Modification of the internal ribosome entry site element impairs the growth of foot-and-mouth disease virus in porcine-derived cells.

    Science.gov (United States)

    Sun, Chao; Yang, Decheng; Gao, Rongyuan; Liang, Te; Wang, Haiwei; Zhou, Guohui; Yu, Li

    2016-04-01

    The 5' untranslated region (5'UTR) of foot-and-mouth disease virus (FMDV) contains an internal ribosome entry site (IRES) that facilitates translation initiation of the viral ORF in a 5' (m7GpppN) cap-independent manner. IRES elements are responsible for the virulence phenotypes of several enteroviruses. Here, we constructed a chimeric virus in which the IRES of FMDV was completely replaced with that of bovine rhinitis B virus (BRBV) in an infectious clone of serotype O FMDV. The resulting IRES-replaced virus, FMDV(BRBV), replicated as efficiently as WT FMDV in hamster-derived BHK-21 cells, but was restricted for growth in porcine-derived IBRS-2, PK-15 and SK-6 cells, which are susceptible to WT FMDV. To identify the genetic determinants of FMDV underlying this altered cell tropism, a series of IRES-chimeric viruses were constructed in which each domain of the FMDV IRES was replaced with its counterpart from the BRBV IRES. The replication kinetics of these chimeric viruses in different cell lines revealed that the growth restriction phenotype in porcine-derived cells was produced after the replacement of domain 3 or 4 in the FMDV IRES. Furthermore, the change in FMDV cell tropism due to IRES replacement in porcine-derived cells was mainly attributed to a decline in cell-specific IRES translation initiation efficiency. These findings demonstrate that IRES domains 3 and 4 of FMDV are novel cell-specific cis-elements for viral replication in vitro and suggest that IRES-mediated translation determines the species specificity of FMDV infection in vivo. PMID:26795299

  17. Passatempo Virus, a Vaccinia Virus Strain, Brazil

    OpenAIRE

    Leite, Juliana A.; Drumond, Betânia P.; Trindade, Giliane S; Zélia I P Lobato; da Fonseca, Flávio G.; dos Santos, João R.; Madureira, Marieta C.; Guedes, Maria I.M.C.; Ferreira, Jaqueline M. S.; Bonjardim, Cláudio A.; Ferreira, Paulo C. P.; Kroon, Erna G.

    2005-01-01

    Passatempo virus was isolated during a zoonotic outbreak. Biologic features and molecular characterization of hemagglutinin, thymidine kinase, and vaccinia growth factor genes suggested a vaccinia virus infection, which strengthens the idea of the reemergence and circulation of vaccinia virus in Brazil. Molecular polymorphisms indicated that Passatempo virus is a different isolate.

  18. Recombinant Virus Vaccination against “Self” Antigens Using Anchor-fixed Immunogens

    OpenAIRE

    Irvine, Kari R.; Parkhurst, Maria R.; Shulman, Eliza P.; Tupesis, Janis P; Custer, Mary; Touloukian, Christopher E; Robbins, Paul F.; Yafal, Alicia Gómez; Greenhalgh, Patricia; Sutmuller, Roger P.M.; Offringa, Rienk; Rosenberg, Steven A.; Restifo, Nicholas P

    1999-01-01

    To study the induction of anti-“self” CD8+ T-cell reactivity against the tumor antigen gp100, we used a mouse transgenic for a chimeric HLA-A*0201/H-2 Kb molecule (A2/Kb). We immunized the mice with a recombinant vaccinia virus encoding a form of gp100 that had been modified at position 210 (from a threonine to a methionine) to increase epitope binding to the restricting class I molecule. Immunogens containing the “anchor-fixed” modification elicited anti-self CD8+ T cells specific for the wi...

  19. High-yield production of canine parvovirus virus-like particles in a baculovirus expression system.

    Science.gov (United States)

    Jin, Hongli; Xia, Xiaohong; Liu, Bing; Fu, Yu; Chen, Xianping; Wang, Huihui; Xia, Zhenqiang

    2016-03-01

    An optimized VP2 gene from the current prevalent CPV strain (new CPV-2a) in China was expressed in a baculovirus expression system. It was found that the VP2 proteins assembled into virus-like particles (VLPs) with antigenic properties similar to those of natural CPV and with an especially high hemagglutination (HA) titer (1:2(20)). Dogs intramuscularly or orally immunized with VLPs produced antibodies against CPV with >1:80 hemagglutination inhibition (HI) units for at least 3 months. The CPV VLPs could be considered for use as a vaccine against CPV or as a platform for research on chimeric VLP vaccines against other diseases. PMID:26666439

  20. Na+/H+ exchanger type 1 is a receptor for pathogenic subgroup J avian leukosis virus

    OpenAIRE

    Chai, Ning; Bates, Paul

    2006-01-01

    Subgroup J avian leukosis virus (ALV-J) is a recently identified avian oncogenic retrovirus responsible for severe economic losses worldwide. In contrast with the other ALV subgroups, ALV-J predominantly induces myeloid leukosis in meat-type chickens. Despite significant homology with the other ALV subgroups across most of the genome, the envelope protein of ALV-J (EnvJ) shares low homology with the others. Pathogenicity and myeloid leukosis induction map to the env gene of ALV-J. A chimeric ...

  1. Local and systemic immune responses induced by a recombinant chimeric protein containing Mycoplasma hyopneumoniae antigens fused to the B subunit of Escherichia coli heat-labile enterotoxin LTB.

    Science.gov (United States)

    Marchioro, Silvana Beutinger; Fisch, Andressa; Gomes, Charles K; Jorge, Sérgio; Galli, Vanessa; Haesebrouck, Freddy; Maes, Dominiek; Dellagostin, Odir; Conceição, Fabricio R

    2014-09-17

    A multi-antigen chimera composed of three antigens of Mycoplasma hyopneumoniae (R1, P42, and NrdF) and the mucosal adjuvant Escherichia coli heat-labile enterotoxin B subunit (LTB) was constructed, and its antigenic and immunogenic properties were evaluated in mice and pigs. In addition, we compared the effect of the fusion and co-administration of these proteins in mice. Antibodies against each subunit recognized the chimeric protein. Intranasal and intramuscular immunization of mice with the chimeric protein significantly increased IgG and IgA levels in the serum and tracheobronchial lavages, respectively, against some of the antigens present in the chimeric. Swine immunized with the chimeric protein developed an immune response against all M. hyopneumoniae antigens present in the fusion with a statistically significant difference (Phyopneumoniae infection. PMID:25091529

  2. Oropuche virus: A virus present but ignored

    Directory of Open Access Journals (Sweden)

    Salim Mattar V.

    2015-09-01

    Full Text Available Bunyaviruses are RNA viruses that affect animals and plants; they have five genera and four of them affect humans: Orthobunyavirus, Nairovirus, Phlebovirus and Hantavirus. All of them are Arbovirus, except Hantavirus. The Orthobunyaviruses comprise Oropouche, Tahyna, La Crosse virus, California encephalitis virus and Heartland virus recently discovered (1. Except for Heartland virus which is transmitted by ticks of the genus Amblyoma, these Phleboviruses have as vectors mosquitoes, which bite small mammals which are able to be as reservoirs amplifiers.

  3. The V domain of dog PVRL4 (nectin-4) mediates canine distemper virus entry and virus cell-to-cell spread

    International Nuclear Information System (INIS)

    The entry of canine distemper virus (CDV) is a multistep process that involves the attachment of CDV hemagglutinin (H) to its cellular receptor, followed by fusion between virus and cell membranes. Our laboratory recently identified PVRL4 (nectin-4) to be the epithelial receptor for measles and canine distemper viruses. In this study, we demonstrate that the V domain of PVRL4 is critical for CDV entry and virus cell-to-cell spread. Furthermore, four key amino acid residues within the V domain of dog PVRL4 and two within the CDV hemagglutinin were shown to be essential for receptor-mediated virus entry. - Highlights: • PVRL4 (nectin-4) is the epithelial cell receptor for measles and canine distemper viruses. • V domain of PVRL4 is critical for CDV entry, cell-to-cell spread, and syncytia formation. • Chimeric PVRL1 backbone substituted with the V domain of PVRL4 can function as a receptor. • Amino acids (F132/P133/A134/G135) within the V domain are essential for PVRL4 receptor activity. • Amino acids (P493/Y539) within CDV H protein are essential for PVRL4 receptor interaction

  4. The V domain of dog PVRL4 (nectin-4) mediates canine distemper virus entry and virus cell-to-cell spread

    Energy Technology Data Exchange (ETDEWEB)

    Delpeut, Sebastien; Noyce, Ryan S. [The Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada B3H 1X5 (Canada); IWK Health Centre, Canadian Center for Vaccinology, Goldbloom Pavilion, Halifax, Nova Scotia, Canada B3H 1X5 (Canada); Richardson, Christopher D., E-mail: chris.richardson@dal.ca [The Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada B3H 1X5 (Canada); IWK Health Centre, Canadian Center for Vaccinology, Goldbloom Pavilion, Halifax, Nova Scotia, Canada B3H 1X5 (Canada); The Department of Pediatrics, Dalhousie University, Halifax, Nova Scotia (Canada)

    2014-04-15

    The entry of canine distemper virus (CDV) is a multistep process that involves the attachment of CDV hemagglutinin (H) to its cellular receptor, followed by fusion between virus and cell membranes. Our laboratory recently identified PVRL4 (nectin-4) to be the epithelial receptor for measles and canine distemper viruses. In this study, we demonstrate that the V domain of PVRL4 is critical for CDV entry and virus cell-to-cell spread. Furthermore, four key amino acid residues within the V domain of dog PVRL4 and two within the CDV hemagglutinin were shown to be essential for receptor-mediated virus entry. - Highlights: • PVRL4 (nectin-4) is the epithelial cell receptor for measles and canine distemper viruses. • V domain of PVRL4 is critical for CDV entry, cell-to-cell spread, and syncytia formation. • Chimeric PVRL1 backbone substituted with the V domain of PVRL4 can function as a receptor. • Amino acids (F132/P133/A134/G135) within the V domain are essential for PVRL4 receptor activity. • Amino acids (P493/Y539) within CDV H protein are essential for PVRL4 receptor interaction.

  5. Development of a Human Immunodeficiency Virus Type 1-Based Lentiviral Vector That Allows Efficient Transduction of both Human and Rhesus Blood Cells▿ †

    OpenAIRE

    Uchida, Naoya; Washington, Kareem N.; Hayakawa, Jun; Hsieh, Matthew M.; Bonifacino, Aylin C.; Krouse, Allen E.; Metzger, Mark E.; Donahue, Robert E.; Tisdale, John F.

    2009-01-01

    Human immunodeficiency virus type 1 (HIV-1) vectors transduce rhesus blood cells poorly due to a species-specific block by TRIM5α and APOBEC3G, which target HIV-1 capsid and viral infectivity factor (Vif), respectively. We sought to develop a lentiviral vector capable of transducing both human and rhesus blood cells by combining components of both HIV-1 and simian immunodeficiency virus (SIV), including SIV capsid (sCA) and SIV Vif. A chimeric HIV-1 vector including sCA (χHIV) was superior to...

  6. Quantitative and Qualitative Involvement of P3N-PIPO in Overcoming Recessive Resistance against Clover Yellow Vein Virus in Pea Carrying the cyv1 Gene

    OpenAIRE

    Choi, Sun Hee; Hagiwara-Komoda, Yuka; Nakahara, Kenji S.; Atsumi, Go; Shimada, Ryoko; Hisa, Yusuke; Naito, Satoshi; Uyeda, Ichiro

    2013-01-01

    In pea carrying cyv1, a recessive gene for resistance to Clover yellow vein virus (ClYVV), ClYVV isolate Cl-no30 was restricted to the initially infected cells, whereas isolate 90-1 Br2 overcame this resistance. We mapped the region responsible for breaking of cyv1-mediated resistance by examining infection of cyv1 pea with chimeric viruses constructed from parts of Cl-no30 and 90-1 Br2. The breaking of resistance was attributed to the P3 cistron, which is known to produce two proteins: P3, f...

  7. An Unusual Chimeric Diterpene Synthase from Emericella variecolor and Its Functional Conversion into a Sesterterpene Synthase by Domain Swapping.

    Science.gov (United States)

    Qin, Bin; Matsuda, Yudai; Mori, Takahiro; Okada, Masahiro; Quan, Zhiyang; Mitsuhashi, Takaaki; Wakimoto, Toshiyuki; Abe, Ikuro

    2016-01-01

    Di- and sesterterpene synthases produce C20 and C25 isoprenoid scaffolds from geranylgeranyl pyrophosphate (GGPP) and geranylfarnesyl pyrophosphate (GFPP), respectively. By genome mining of the fungus Emericella variecolor, we identified a multitasking chimeric terpene synthase, EvVS, which has terpene cyclase (TC) and prenyltransferase (PT) domains. Heterologous gene expression in Aspergillus oryzae led to the isolation of variediene (1), a novel tricyclic diterpene hydrocarbon. Intriguingly, in vitro reaction with the enzyme afforded the new macrocyclic sesterterpene 2 as a minor product from dimethylallyl pyrophosphate (DMAPP) and isopentenyl pyrophosphate (IPP). The TC domain thus produces the diterpene 1 and the sesterterpene 2 from GGPP and GFPP, respectively. Notably, a domain swap of the PT domain of EvVS with that of another chimeric sesterterpene synthase, EvSS, successfully resulted in the production of 2 in vivo as well. Cyclization mechanisms for the production of these two compounds are proposed. PMID:26546087

  8. ReX: A suite of computational tools for the design, visualization, and analysis of chimeric protein libraries.

    Science.gov (United States)

    Huang, Weiliang; Johnston, Wayne A; Boden, Mikael; Gillam, Elizabeth M J

    2016-02-01

    Directed evolution has greatly facilitated protein engineering and provided new insights into protein structure-function relationships. DNA shuffling using restriction enzymes is a particularly simple and cost-effective means of recombinatorial evolution that is well within the capability of most molecular biologists, but tools for the design and analysis of such experiments are limited. Here we introduce a suite of freely available online tools to make the construction and analysis of chimeric libraries readily accessible to the novice. REcut (http://qpmf.rx.umaryland.edu/REcut.html) facilitates the choice of DNA fragmentation strategy, while Xover (http://qpmf.rx.umaryland.edu/Xover.html) analyzes chimeric mutants to reveal recombination patterns and extract quantitative data. PMID:26842355

  9. Vaccine candidates for dengue virus type 1 (DEN1 generated by replacement of the structural genes of rDEN4 and rDEN4Δ30 with those of DEN1

    Directory of Open Access Journals (Sweden)

    Blaney Joseph E

    2007-02-01

    Full Text Available Abstract Background Antigenic chimeric viruses have previously been generated in which the structural genes of recombinant dengue virus type 4 (rDEN4 have been replaced with those derived from DEN2 or DEN3. Two vaccine candidates were identified, rDEN2/4Δ30(ME and rDEN3/4Δ30(ME, which contain the membrane (M precursor and envelope (E genes of DEN2 and DEN3, respectively, and a 30 nucleotide deletion (Δ30 in the 3' untranslated region of the DEN4 backbone. Based on the promising preclinical phenotypes of these viruses and the safety and immunogenicity of rDEN2/4Δ30(ME in humans, we now describe the generation of a panel of four antigenic chimeric DEN4 viruses using either the capsid (C, M, and E (CME or ME structural genes of DEN1 Puerto Rico/94 strain. Results Four antigenic chimeric viruses were generated and found to replicate efficiently in Vero cells: rDEN1/4(CME, rDEN1/4Δ30(CME, rDEN1/4(ME, and rDEN1/4Δ30(ME. With the exception of rDEN1/4(ME, each chimeric virus was significantly attenuated in a SCID-HuH-7 mouse xenograft model with a 25-fold or greater reduction in replication compared to wild type DEN1. In rhesus monkeys, only chimeric viruses with the Δ30 mutation appeared to be attenuated as measured by duration and magnitude of viremia. rDEN1/4Δ30(CME appeared over-attenuated since it failed to induce detectable neutralizing antibody and did not confer protection from wild type DEN1 challenge. In contrast, rDEN1/4Δ30(ME induced 66% seroconversion and protection from DEN1 challenge. Presence of the Δ30 mutation conferred a significant restriction in mosquito infectivity upon rDEN1/4Δ30(ME which was shown to be non-infectious for Aedes aegypti fed an infectious bloodmeal. Conclusion The attenuation phenotype in SCID-HuH-7 mice, rhesus monkeys, and mosquitoes and the protective immunity observed in rhesus monkeys suggest that rDEN1/4Δ30(ME should be considered for evaluation in a clinical trial.

  10. A Chimeric Protein That Functions as both an Anthrax Dual-Target Antitoxin and a Trivalent Vaccine▿

    OpenAIRE

    Wu, Gaobing; Hong, Yuzhi; Guo, Aizhen; Feng, Chunfang; Cao, Sha; Zhang, Cheng-Cai; Shi, Ruiping; Tan, Yadi; Liu, Ziduo

    2010-01-01

    Effective measures for the prophylaxis and treatment of anthrax are still required for counteracting the threat posed by inhalation anthrax. In this study, we first demonstrated that the chimeric protein LFn-PA, created by fusing the protective antigen (PA)-binding domain of lethal factor (LFn) to PA, retained the functions of the respective molecules. On the basis of this observation, we attempted to develop an antitoxin that targets the binding of lethal factor (LF) and/or edema factor (EF)...

  11. MURINE MOBILIZED PERIPHERAL BLOOD STEM CELLS HAVE A LOWER CAPACITY THAN BONE MARROW TO INDUCE MIXED CHIMERISM AND TOLERANCE

    OpenAIRE

    Koporc, Zvonimir; Pilat, Nina; Nierlich, Patrick; Blaha, Peter; Bigenzahn, Sinda; Pree, Ines; Selzer, Edgar; Sykes, Megan; Muehlbacher, Ferdinand; Wekerle, Thomas

    2008-01-01

    Allogeneic bone marrow transplantation (BMT) under costimulation blockade allows induction of mixed chimerism and tolerance without global T cell depletion. The mildest such protocols without recipient cytoreduction, however, require clinically impracticable bone marrow (BM) doses. The successful use of mobilized peripheral blood stem cells (PBSC) instead of BM in such regimens would provide a substantial advance, allowing transplantation of higher doses of hematopoietic donor cells. We thus ...

  12. Chimeric β-lactamases: global conservation of parental function and fast time-scale dynamics with increased slow motions.

    Directory of Open Access Journals (Sweden)

    Christopher M Clouthier

    Full Text Available Enzyme engineering has been facilitated by recombination of close homologues, followed by functional screening. In one such effort, chimeras of two class-A β-lactamases - TEM-1 and PSE-4 - were created according to structure-guided protein recombination and selected for their capacity to promote bacterial proliferation in the presence of ampicillin (Voigt et al., Nat. Struct. Biol. 2002 9:553. To provide a more detailed assessment of the effects of protein recombination on the structure and function of the resulting chimeric enzymes, we characterized a series of functional TEM-1/PSE-4 chimeras possessing between 17 and 92 substitutions relative to TEM-1 β-lactamase. Circular dichroism and thermal scanning fluorimetry revealed that the chimeras were generally well folded. Despite harbouring important sequence variation relative to either of the two 'parental' β-lactamases, the chimeric β-lactamases displayed substrate recognition spectra and reactivity similar to their most closely-related parent. To gain further insight into the changes induced by chimerization, the chimera with 17 substitutions was investigated by NMR spin relaxation. While high order was conserved on the ps-ns timescale, a hallmark of class A β-lactamases, evidence of additional slow motions on the µs-ms timescale was extracted from model-free calculations. This is consistent with the greater number of resonances that could not be assigned in this chimera relative to the parental β-lactamases, and is consistent with this well-folded and functional chimeric β-lactamase displaying increased slow time-scale motions.

  13. Broad neutralization of calcium-permeable amyloid pore channels with a chimeric Alzheimer/Parkinson peptide targeting brain gangliosides.

    Science.gov (United States)

    Di Scala, Coralie; Yahi, Nouara; Flores, Alessandra; Boutemeur, Sonia; Kourdougli, Nazim; Chahinian, Henri; Fantini, Jacques

    2016-02-01

    Growing evidence supports a role for brain gangliosides in the pathogenesis of neurodegenerative diseases including Alzheimer's and Parkinson's. Recently we deciphered the ganglioside-recognition code controlling specific ganglioside binding to Alzheimer's β-amyloid (Aβ1-42) peptide and Parkinson's disease-associated protein α-synuclein. Cracking this code allowed us to engineer a short chimeric Aβ/α-synuclein peptide that recognizes all brain gangliosides. Here we show that ganglioside-deprived neural cells do no longer sustain the formation of zinc-sensitive amyloid pore channels induced by either Aβ1-42 or α-synuclein, as assessed by single-cell Ca(2+) fluorescence microscopy. Thus, amyloid channel formation, now considered a key step in neurodegeneration, is a ganglioside-dependent process. Nanomolar concentrations of chimeric peptide competitively inhibited amyloid pore formation induced by Aβ1-42 or α-synuclein in cultured neural cells. Moreover, this peptide abrogated the intracellular calcium increases induced by Parkinson's-associated mutant forms of α-synuclein (A30P, E46K and A53T). The chimeric peptide also prevented the deleterious effects of Aβ1-42 on synaptic vesicle trafficking and decreased the Aβ1-42-induced impairment of spontaneous activity in rat hippocampal slices. Taken together, these data show that the chimeric peptide has broad anti-amyloid pore activity, suggesting that a common therapeutic strategy based on the prevention of amyloid-ganglioside interactions is a reachable goal for both Alzheimer's and Parkinson's diseases. PMID:26655601

  14. Inducible Expression of Chimeric EWS/ETS Proteins Confers Ewing's Family Tumor-Like Phenotypes to Human Mesenchymal Progenitor Cells

    OpenAIRE

    Miyagawa, Yoshitaka; Okita, Hajime; Nakaijima, Hideki; Horiuchi, Yasuomi; Sato, Ban; TAGUCHI, Tomoko; Toyoda, Masashi; Katagiri, Yohko U; Fujimoto, Junichiro; Hata, Jun-Ichi; Umezawa, Akihiro; Kiyokawa, Nobutaka

    2008-01-01

    Ewing's family tumor (EFT) is a rare pediatric tumor of unclear origin that occurs in bone and soft tissue. Specific chromosomal translocations found in EFT cause EWS to fuse to a subset of ets transcription factor genes (ETS), generating chimeric EWS/ETS proteins. These proteins are believed to play a crucial role in the onset and progression of EFT. However, the mechanisms responsible for the EWS/ETS-mediated onset remain unclear. Here we report the establishment of a tetracycline-controlle...

  15. Cellular and humoral immune responses to chimeric EGFP-pseudocapsids derived from the mouse polyomavirus after their intranasal administration

    Czech Academy of Sciences Publication Activity Database

    Frič, Jan; Marek, M.; Hrušková, V.; Holáň, Vladimír; Forstová, J.

    2008-01-01

    Roč. 26, č. 26 (2008), s. 3242-3251. ISSN 0264-410X R&D Projects: GA MŠk 1M0506; GA MŠk LC545 Grant ostatní: GA Mšk(CZ) 1M0508 Institutional research plan: CEZ:AV0Z50520514 Keywords : mouse polyomavirus pseudocapsids * chimeric VLPs * antigen carrier and adjuvant Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.298, year: 2008

  16. Mutation of the Fiber Shaft Heparan Sulphate Binding Site of a 5/3 Chimeric Adenovirus Reduces Liver Tropism

    OpenAIRE

    Koski, Anniina; Karli, Eerika; Kipar, Anja; Escutenaire, Sophie; Kanerva, Anna; Hemminki, Akseli

    2013-01-01

    Natural tropism to the liver is a major obstacle in systemic delivery of adenoviruses in cancer gene therapy. Adenovirus binding to soluble coagulation factors and to cellular heparan sulphate proteoglycans via the fiber shaft KKTK domain are suggested to cause liver tropism. Serotype 5 adenovirus constructs with mutated KKTK regions exhibit liver detargeting, but they also transduce tumors less efficiently, possibly due to altered fiber conformation. We constructed Ad5/3lucS*, a 5/3 chimeric...

  17. Hematopoietic microenvironment. Origin, lineage, and transplantability of the stromal cells in long-term bone marrow cultures from chimeric mice.

    OpenAIRE

    Perkins, S; Fleischman, R A

    1988-01-01

    Studies of bone marrow transplant patients have suggested that the stromal cells of the in vitro hematopoietic microenvironment are transplantable into conditioned recipients. Moreover, in patients with myeloproliferative disorders, all of the stromal cells, which include presumptive endothelial cells, appear to be derived from hematopoietic precursors. To confirm these findings, we have constructed two chimeric mouse models: (a) traditional radiation chimeras, and (b) fetal chimeras, produce...

  18. Protein L: a novel reagent for the detection of Chimeric Antigen Receptor (CAR) expression by flow cytometry

    OpenAIRE

    Zheng Zhili; Chinnasamy Nachimuthu; Morgan Richard A

    2012-01-01

    Abstract Background There has been significant progress in the last two decades on the design of chimeric antigen receptors (CAR) for adoptive immunotherapy targeting tumor-associated antigens. Structurally CARs consist of a single chain antibody fragment directed against a tumor-associated antigen fused to an extracellular spacer and transmembrane domain followed by T cell cytoplasmic signaling moieties. Currently several clinical trials are underway using gene modified peripheral blood lymp...

  19. Regulation of expression of two LY-6 family genes by intron retention and transcription induced chimerism

    Directory of Open Access Journals (Sweden)

    Mallya Meera

    2008-09-01

    Full Text Available Abstract Background Regulation of the expression of particular genes can rely on mechanisms that are different from classical transcriptional and translational control. The LY6G5B and LY6G6D genes encode LY-6 domain proteins, whose expression seems to be regulated in an original fashion, consisting of an intron retention event which generates, through an early premature stop codon, a non-coding transcript, preventing expression in most cell lines and tissues. Results The MHC LY-6 non-coding transcripts have shown to be stable and very abundant in the cell, and not subject to Nonsense Mediated Decay (NMD. This retention event appears not to be solely dependent on intron features, because in the case of LY6G5B, when the intron is inserted in the artificial context of a luciferase expression plasmid, it is fully spliced but strongly stabilises the resulting luciferase transcript. In addition, by quantitative PCR we found that the retained and spliced forms are differentially expressed in tissues indicating an active regulation of the non-coding transcript. EST database analysis revealed that these genes have an alternative expression pathway with the formation of Transcription Induced Chimeras (TIC. This data was confirmed by RT-PCR, revealing the presence of different transcripts that would encode the chimeric proteins CSNKβ-LY6G5B and G6F-LY6G6D, in which the LY-6 domain would join to a kinase domain and an Ig-like domain, respectively. Conclusion In conclusion, the LY6G5B and LY6G6D intron-retained transcripts are not subjected to NMD and are more abundant than the properly spliced forms. In addition, these genes form chimeric transcripts with their neighbouring same orientation 5' genes. Of interest is the fact that the 5' genes (CSNKβ or G6F undergo differential splicing only in the context of the chimera (CSNKβ-LY6G5B or G6F-LY6G6C and not on their own.

  20. Plant Virus Metagenomics: Advances in Virus Discovery.

    Science.gov (United States)

    Roossinck, Marilyn J; Martin, Darren P; Roumagnac, Philippe

    2015-06-01

    In recent years plant viruses have been detected from many environments, including domestic and wild plants and interfaces between these systems-aquatic sources, feces of various animals, and insects. A variety of methods have been employed to study plant virus biodiversity, including enrichment for virus-like particles or virus-specific RNA or DNA, or the extraction of total nucleic acids, followed by next-generation deep sequencing and bioinformatic analyses. All of the methods have some shortcomings, but taken together these studies reveal our surprising lack of knowledge about plant viruses and point to the need for more comprehensive studies. In addition, many new viruses have been discovered, with most virus infections in wild plants appearing asymptomatic, suggesting that virus disease may be a byproduct of domestication. For plant pathologists these studies are providing useful tools to detect viruses, and perhaps to predict future problems that could threaten cultivated plants. PMID:26056847

  1. Generation of porcine reproductive and respiratory syndrome virus by in vitro assembly of viral genomic cDNA fragments.

    Science.gov (United States)

    Suhardiman, Maman; Kramyu, Jarin; Narkpuk, Jaraspim; Jongkaewwattana, Anan; Wanasen, Nanchaya

    2015-01-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) is the causative agent for a swine disease affecting the pig industry worldwide. Infection with PRRSV leads to reproductive complications, respiratory illness, and weak immunity to secondary infections. To better control PRRSV infection, novel approaches for generating control measures are critically needed. Here, in vitro Gibson assembly (GA) of viral genomic cDNA fragments was tested for its use as a quick and simple method to recover infectious PRRSV in cell culture. GA involves the activities of T5-exonuclease, Phusion polymerase, and Taq ligase to join overlapping cDNA fragments in an isothermal condition. Four overlapping cDNA fragments covering the entire PRRSV genome and one vector fragment were used to create a plasmid capable of expressing the PRRSV genome. The assembled product was used to transfect a co-culture of 293T and MARC-145 cells. Supernatants from the transfected cells were then passaged onto MARC-145 cells to rescue infectious virus particles. Verification and characterization of the recovered virus confirmed that the GA protocol generated infectious PRRSV that had similar characteristics to the parental virus. This approach was then tested for the generation of a chimeric virus. By replacing one of the four genomic fragments with that of another virus strain, a chimeric virus was successfully recovered via GA. In conclusion, this study describes for the first time the use of GA as a simple, yet powerful tool for generating infectious PRRSV needed for studying PRRSV biology and developing novel vaccines. PMID:25300804

  2. Newcastle disease virus chimeras expressing the Hemagglutinin- Neuraminidase protein of mesogenic strain exhibits an enhanced anti-hepatoma efficacy.

    Science.gov (United States)

    He, Jinjiao; Pan, Ziye; Tian, Guiyou; Liu, Xin; Liu, Yunye; Guo, Xiaochen; An, Ying; Song, Liying; Wu, Hongsong; Cao, Hongwei; Yu, Dan; Che, Ruixiang; Xu, Pengfei; Rasoul, Lubna M; Li, Deshan; Yin, Jiechao

    2016-08-01

    Newcastle disease virus (NDV) is an intrinsically tumor-specific virus, many researchers have reported that lentogenic NDV is a safe and effective agent for human cancer therapy. It had been demonstrated that the amino acid sequence of the fusion protein cleavage site is a major factor in the pathogenicity and anti-tumor efficacy of rNDV. However, the role of Hemagglutinin-Neuraminidase (HN) gene that contributes to virulence and anti-tumor efficacy remains undefined. To assess the role of HN gene in virus pathogenicity and anti-tumor efficacy, a reverse genetic system was developed using the lentogenic NDV Clone30 strain to provide backbone for gene exchange. Chimeric virus (rClone30-Anh(HN)) created by exchange of the HN gene of lentogenic strain Clone30 with HN gene of mesogenic strain produce no significant changes in virus pathogenicity as assessed by conducting the mean death time (MDT) and intracerebral pathogenicity index (ICPI) assays. In vitro, infection with chimeras could induce the formation of syncytium relative significantly in HepG2 cells. Furthermore, chimeras was shown to induce the cell apoptosis via MTT and Annexin V-PI assays, reduce mitochondrial membrane potential and increase the mRNA transcription level of caspase 3. In vivo, ICR mice carrying tumor of hepatoma H22 cells were treated via intratumoral injection of chimeric virus. The treatment of chimera shows an obvious suppression in tumor volume. These results suggest that it could be an ideal approach to enhance the antitumor ability of Newcastle disease virus and highlighted the potential therapeutic application of rClone30-Anh(HN) as a viral vector to deliver foreign genes for treatment of cancers. PMID:27164362

  3. Intranasal Immunization with Influenza Virus-Like Particles Containing Membrane-Anchored Cholera Toxin B or Ricin Toxin B Enhances Adaptive Immune Responses and Protection against an Antigenically Distinct Virus

    Science.gov (United States)

    Ji, Xianliang; Ren, Zhiguang; Xu, Na; Meng, Lingnan; Yu, Zhijun; Feng, Na; Sang, Xiaoyu; Li, Shengnan; Li, Yuanguo; Wang, Tiecheng; Zhao, Yongkun; Wang, Hualei; Zheng, Xuexing; Jin, Hongli; Li, Nan; Yang, Songtao; Cao, Jinshan; Liu, Wensen; Gao, Yuwei; Xia, Xianzhu

    2016-01-01

    Vaccination is the most effective means to prevent influenza virus infection, although current approaches are associated with suboptimal efficacy. Here, we generated virus-like particles (VLPs) composed of the hemagglutinin (HA), neuraminidase (NA) and matrix protein (M1) of A/Changchun/01/2009 (H1N1) with or without either membrane-anchored cholera toxin B (CTB) or ricin toxin B (RTB) as molecular adjuvants. The intranasal immunization of mice with VLPs containing membrane-anchored CTB or RTB elicited stronger humoral and cellular immune responses when compared to mice immunized with VLPs alone. Administration of VLPs containing CTB or RTB significantly enhanced virus-specific systemic and mucosal antibody responses, hemagglutination inhibiting antibody titers, virus neutralizing antibody titers, and the frequency of virus-specific IFN-γ and IL-4 secreting splenocytes. VLPs with and without CTB or RTB conferred complete protection against lethal challenge with a mouse-adapted homologous virus. When challenged with an antigenically distinct H1N1 virus, all mice immunized with VLPs containing CTB or RTB survived whereas mice immunized with VLPs alone showed only partial protection (80% survival). Our results suggest that membrane-anchored CTB and RTB possess strong adjuvant properties when incorporated into an intranasally-delivered influenza VLP vaccine. Chimeric influenza VLPs containing CTB or RTB may represent promising vaccine candidates for improved immunological protection against homologous and antigenically distinct influenza viruses. PMID:27110810

  4. Assessing the ammonium nitrate formation regime in the Paris megacity and its representation in the CHIMERE model

    Science.gov (United States)

    Petetin, Hervé; Sciare, Jean; Beekmann, Matthias; Sanchez, Olivier; Rosso, Amandine; Denier van der Gon, Hugo

    2014-05-01

    Ammonium nitrates significantly contribute to the fine particulate matter load, in particular in the Paris agglomeration where two measurement campaigns, PARTICULES and FRANCIPOL, have recently made available a large database on this compound and its gaseous precursors, nitric acid and ammonia. These new observations give the opportunity (for the first time in France) to assess the ammonium nitrate formation regime (in terms of limited species) as well as the ability of the CHIMERE chemistry-transport model to simulate each species and to reproduce in fine the observed regime. Quite satisfactory results are obtained on nitrates, mainly due to a significant contribution of imports from outside the agglomeration. However, significant biases affect both gaseous precursors. Various uncertainty sources are discussed, including those relative to ammonia trafic and agricultural emissions, thermodynamic equilibria or oxidative capacity of the atmosphere. Despite these errors, CHIMERE manages to simulate a HNO3-limited regime, in agreement with observations, at least at the daily scale. This study especially confirms that further work on the OH radical characterization in the CHIMERE model and agricultural ammonia emissions are required to improve the simulation of the ammonium nitrate formation regime.

  5. Nanobody-based chimeric receptor gene integration in Jurkat cells mediated by PhiC31 integrase

    Energy Technology Data Exchange (ETDEWEB)

    Iri-Sofla, Farnoush Jafari [Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Rahbarizadeh, Fatemeh, E-mail: rahbarif@modares.ac.ir [Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Ahmadvand, Davoud [Center of Pharmaceutical Nanotechnology and Nanotoxicology, Department of Pharmaceutics and Analytical Chemistry, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen O (Denmark); Rasaee, Mohammad J. [Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)

    2011-11-01

    The crucial role of T lymphocytes in anti-tumor immunity has led to the development of novel strategies that can target and activate T cells against tumor cells. Recombinant DNA technology has been used to generate non-MHC-restricted chimeric antigen receptors (CARs). Here, we constructed a panel of recombinant CAR that harbors the anti-MUC1 nanobody and the signaling and co-signaling moieties (CD3{zeta}/CD28) with different spacer regions derived from human IgG3 with one or two repeats of the hinge sequence or the hinge region of Fc{gamma}RII. The PhiC31 integrase system was employed to investigate if the recombination efficiency could be recruited for high and stable expression of T cell chimeric receptor genes. The effect of nuclear localization signal (NLS) and two different promoters (CMV and CAG) on efficacy of PhiC31 integrase in human T cell lines was evaluated. The presence of integrase in combination with NLS, mediated up to 7.6 and 8.5 fold increases in CAR expression in ZCHN-attB and ZCHHN-attB cassette integrated T cells, respectively. Our results showed that highly efficient and stable transduction of the Jurkat cell line by PhiC31 integrase is a feasible modality for generating anti-cancer chimeric T cells for use in cancer immunotherapy.

  6. Nanobody-based chimeric receptor gene integration in Jurkat cells mediated by PhiC31 integrase

    International Nuclear Information System (INIS)

    The crucial role of T lymphocytes in anti-tumor immunity has led to the development of novel strategies that can target and activate T cells against tumor cells. Recombinant DNA technology has been used to generate non-MHC-restricted chimeric antigen receptors (CARs). Here, we constructed a panel of recombinant CAR that harbors the anti-MUC1 nanobody and the signaling and co-signaling moieties (CD3ζ/CD28) with different spacer regions derived from human IgG3 with one or two repeats of the hinge sequence or the hinge region of FcγRII. The PhiC31 integrase system was employed to investigate if the recombination efficiency could be recruited for high and stable expression of T cell chimeric receptor genes. The effect of nuclear localization signal (NLS) and two different promoters (CMV and CAG) on efficacy of PhiC31 integrase in human T cell lines was evaluated. The presence of integrase in combination with NLS, mediated up to 7.6 and 8.5 fold increases in CAR expression in ZCHN-attB and ZCHHN-attB cassette integrated T cells, respectively. Our results showed that highly efficient and stable transduction of the Jurkat cell line by PhiC31 integrase is a feasible modality for generating anti-cancer chimeric T cells for use in cancer immunotherapy.

  7. Functional participation of a nifH-arsA2 chimeric fusion gene in arsenic reduction by Escherichia coli

    International Nuclear Information System (INIS)

    The NifH (dimer) and ArsA proteins are structural homologs and share common motifs like nucleotide-binding domains, signal transduction domains and also possible similar metal center ligands. Given the similarity between two proteins, we investigated if the NifH protein from Azotobacter vinelandii could functionally substitute for the ArsA1 half of the ArsA protein of Escherichia coli. The chimeric NifH-ArsA2 protein was expressed and detected in the E. coli strain by Western blotting. Growth comparisons of E. coli strains containing plasmids encoding for complete ArsA, partial ArsA (ArsA2) or chimeric ArsA (NifH-ArsA2) in media with increasing sodium arsenite concentrations (0-5 mM) showed that the chimeric NifH-ArsA2 could substitute for the ArsA. This functional complementation demonstrated the strong conservation of essential domains that have been maintained in NifH and ArsA even after their divergence to perform varied functions

  8. Construction of an allogenic chimeric mouse model for the study of the behaviors of donor stem cells in vivo

    Institute of Scientific and Technical Information of China (English)

    WANG Mo-lin; YAN Jing-bin; XIAO Yan-ping; HUANG Shu-zhen

    2005-01-01

    Background It is essential to establish an animal model for the elucidation of the biological behaviors of stem cells in vivo. We constructed a chimeric animal model by in utero transplantation for investigation of stem cell transplantation.Methods This chimerism was achieved by injecting the stem cells derived from the bone marrow of green fluorescence protein (GFP)-transgenic mice into fetal mice at 13.5 days of gestation. Several methods such as polymerase chain reaction (PCR), real-time PCR, fluorescence-assisted cell sorting (FACS) and fluorescence in situ hybridization (FISH) were used for the observation of donor cells.Results Under a fluorescence microscope, we observed the GFP cells of donor-origin in a recipient. PCR, FACS analysis and FISH indicated chimerism at various intervals. Real-time PCR indicated that some donor cells existed in chimera for more than 6 months.Conclusions Allogenic stem cells may exist in recipients for a long time and this allogenic animal model provides a useful tool for studying the behavior of hematopoietic stem cells and also offers an effective model system for the study of stem cells.

  9. Ag85A/ESAT-6 chimeric DNA vaccine induces an adverse response in tuberculosis-infected mice

    Science.gov (United States)

    Liang, Yan; Bai, Xuejuang; Zhang, Junxian; Song, Jingying; Yang, Yourong; Yu, Qi; Li, Ning; Wu, Xueqiong

    2016-01-01

    The Mycobacterium tuberculosis (M. tb) antigens encoded by the 6 kDa early secretory antigenic target (esat-6) and antigen 85A (ag85a) genes are known to exert protective effects against tuberculosis in animal models. In addition, these antigens represent vaccine components that were tested in early human clinical trials. In the present study, a chimeric DNA vaccine was constructed that contained two copies of the esat-6 gene inserted into the ag85a gene from M. tb. BALB/c mice were treated with this chimeric vaccine following infection with either M. tb H37Rv or a clinical multi drug resistant tuberculosis isolate. Treatment of both groups of mice with the chimeric vaccine resulted in accelerated mortality. These findings are in contrast with previous results, which indicated that DNA vaccines expressing the individual antigens were either beneficial or at least not harmful. The results of the present study suggested that the ESAT-6 antigen is not suitable for inclusion in therapeutic vaccines. PMID:27279275

  10. A chimeric protein of aluminum-activated malate transporter generated from wheat and Arabidopsis shows enhanced response to trivalent cations.

    Science.gov (United States)

    Sasaki, Takayuki; Tsuchiya, Yoshiyuki; Ariyoshi, Michiyo; Ryan, Peter R; Yamamoto, Yoko

    2016-07-01

    TaALMT1 from wheat (Triticum aestivum) and AtALMT1 from Arabidopsis thaliana encode aluminum (Al)-activated malate transporters, which confer acid-soil tolerance by releasing malate from roots. Chimeric proteins from TaALMT1 and AtALMT1 (Ta::At, At::Ta) were previously analyzed in Xenopus laevis oocytes. Those studies showed that Al could activate malate efflux from the Ta::At chimera but not from At::Ta. Here, functions of TaALMT1, AtALMT1 and the chimeric protein Ta::At were compared in cultured tobacco BY-2 cells. We focused on the sensitivity and specificity of their activation by trivalent cations. The activation of malate efflux by Al was at least two-fold greater in the chimera than the native proteins. All proteins were also activated by lanthanides (erbium, ytterbium, gadolinium, and lanthanum), but the chimera again released more malate than TaALMT1 or AtALMT1. In Xenopus oocytes, Al, ytterbium, and erbium activated inward currents from the native TaALMT1 and the chimeric protein, but gadolinium only activated currents from the chimera. Lanthanum inhibited currents from both proteins. These results demonstrated that function of the chimera protein was altered compared to the native proteins and was more responsive to a range of trivalent cations when expressed in plant cells. PMID:27039280

  11. DPPC/poly(2-methyl-2-oxazoline)-grad-poly(2-phenyl-2-oxazoline) chimeric nanostructures as potential drug nanocarriers

    Energy Technology Data Exchange (ETDEWEB)

    Pippa, Natassa [Faculty of Pharmacy, National and Kapodistrian University of Athens, Department of Pharmaceutical Technology (Greece); Kaditi, Eleni; Pispas, Stergios [Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation (Greece); Demetzos, Costas, E-mail: demetzos@pharm.uoa.gr [Faculty of Pharmacy, National and Kapodistrian University of Athens, Department of Pharmaceutical Technology (Greece)

    2013-06-15

    In this study, we report on the self assembly behavior and on stability studies of mixed (chimeric) nanosystems consisting of dipalmitoylphosphatidylcholine (DPPC) and poly(2-methyl-2-oxazoline)-grad-poly(2-phenyl-2-oxazoline) (MPOx) gradient copolymer in aqueous media and in fetal bovine serum (FBS). A gamut of light scattering techniques and fluorescence spectroscopy were used in order to extract information on the size and morphological characteristics of the nanoassemblies formed, as a function of gradient block copolymer content, as well as temperature. The hydrodynamic radii (R{sub h}) of nanoassemblies decreased in the process of heating up to 50 Degree-Sign C, while the fractal dimension (d{sub f}) values, also increased. Indomethacin was successfully incorporated into these chimeric nanocarriers. Drug release was depended on the components ratio. The present studies show that there are a number of parameters that can be used in order to alter the properties of chimeric nanosystems, and this is advantageous to the development of 'smart' nanocarriers for drug delivery.

  12. Cloning, purification, crystallization and preliminary X-ray analysis of a chimeric NADPH-cytochrome P450 reductase

    International Nuclear Information System (INIS)

    A 2.5 Å resolution data set was collected from a crystal of a soluble chimeric form of NADPH-cytochrome P450 reductase (CPR) produced using a fusion gene composed of the yeast FMN and the human FAD domains. The chimeric protein was crystallized in a modified conformation compared with the previously solved structures. NADPH-cytochrome P450 reductase (CPR) is the favoured redox partner of microsomal cytochromes P450. This protein is composed of two flavin-containing domains (FMN and FAD) connected by a structured linker. An active CPR chimera consisting of the yeast FMN and human FAD domains has been produced, purified and crystallized. The crystals belonged to the monoclinic space group C2 and contained one molecule per asymmetric unit. Molecular replacement was performed using the published rat and yeast structures as search models. The initial electron-density maps revealed that the chimeric enzyme had crystallized in a conformation that differed from those of previously solved structures

  13. Analysis of beta-globin mutations shows stable mixed chimerism in patients with thalassemia after bone marrow transplantation.

    Science.gov (United States)

    Kapelushnik, J; Or, R; Filon, D; Nagler, A; Cividalli, G; Aker, M; Naparstek, E; Slavin, S; Oppenheim, A

    1995-10-15

    Beta-thalassemia major (TM) is caused by any of approximately 150 mutations within the beta-globin gene. To establish the degree of chimerism after bone marrow transplantation (BMT), we have performed molecular analysis of beta-globin mutations in 14 patients with TM over a period of 10 years. All patients underwent T cell-depleted allogeneic BMT from HLA-identical related donors, using either in vitro T-cell depletion with CAMPATH 1M and complement or in vivo depletion using CAMPATH 1G in the bone marrow collection bag. To date, at different time periods after BMT, seven patients have some degree of chimerism; six of these patients, all blood transfusion-independent, have donor cells in the range of 70% to 95%, with stable mixed chimerism (MC). The seventh patient has less than 10% donor cells with, surprisingly, only minimal transfusion requirements. The detection of beta-globin gene point mutation, as used here, is a highly specific and sensitive marker for engraftment and MC in patients with thalassemia. In light of its specificity, the method is applicable in all cases of TM, as it is independent of sex and other non-globin-related DNA markers. The high incidence of MC found in our patients may be a consequence of the pre-BMT T-cell depletion. Because MC was associated with transfusion independence, complete eradication of residual host cells for effective treatment of TM and possibly other genetic diseases may prove not to be essential. PMID:7579421

  14. Zika Virus.

    Science.gov (United States)

    Musso, Didier; Gubler, Duane J

    2016-07-01

    Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) in the genus Flavivirus and the family Flaviviridae. ZIKV was first isolated from a nonhuman primate in 1947 and from mosquitoes in 1948 in Africa, and ZIKV infections in humans were sporadic for half a century before emerging in the Pacific and the Americas. ZIKV is usually transmitted by the bite of infected mosquitoes. The clinical presentation of Zika fever is nonspecific and can be misdiagnosed as other infectious diseases, especially those due to arboviruses such as dengue and chikungunya. ZIKV infection was associated with only mild illness prior to the large French Polynesian outbreak in 2013 and 2014, when severe neurological complications were reported, and the emergence in Brazil of a dramatic increase in severe congenital malformations (microcephaly) suspected to be associated with ZIKV. Laboratory diagnosis of Zika fever relies on virus isolation or detection of ZIKV-specific RNA. Serological diagnosis is complicated by cross-reactivity among members of the Flavivirus genus. The adaptation of ZIKV to an urban cycle involving humans and domestic mosquito vectors in tropical areas where dengue is endemic suggests that the incidence of ZIKV infections may be underestimated. There is a high potential for ZIKV emergence in urban centers in the tropics that are infested with competent mosquito vectors such as Aedes aegypti and Aedes albopictus. PMID:27029595

  15. Computer Viruses: An Overview.

    Science.gov (United States)

    Marmion, Dan

    1990-01-01

    Discusses the early history and current proliferation of computer viruses that occur on Macintosh and DOS personal computers, mentions virus detection programs, and offers suggestions for how libraries can protect themselves and their users from damage by computer viruses. (LRW)

  16. Viruses Infecting Reptiles

    OpenAIRE

    Marschang, Rachel E.

    2011-01-01

    A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The ...

  17. Oncogenic viruses and cancer

    Institute of Scientific and Technical Information of China (English)

    Guangxiang; George; Luo; Jing-hsiung; James; Ou

    2015-01-01

    <正>This special issue of the journal is dedicated to the important topic of oncogenic viruses and cancer.It contains seven review articles covering all known oncogenic viruses except for human T-lymphotropic virus type1(HTLV-1).These review articles are contributed by experts on specific viruses and their associated human cancers.Viruses account for about 20%of total human cancer cases.Although many viruses can cause various tumors in animals,only seven of them

  18. Construction, Expression and Characterization of a Chimeric Protein Targeting Carcinoembryonic Antigen in Lung Cancer

    Institute of Scientific and Technical Information of China (English)

    LI Yang; HUA Shu-cheng; MA Cheng-yuan; YU Zhen-xiang; XU Li-jun; LI Dan; SUN Li-li; LI Xiao; PENG Li-ping

    2011-01-01

    The carcinoembryonic antigen(CEA) is an oncofetal glycoprotein known as an important clinical tumor marker and is overexpressed in several types of tumors, including colorectal and lung carcinomas. We constructed a chimeric protein that exhibits both specific binding and immune stimulating activities, by fusing staphylococcal enterotoxin A(SEA) to the C-terminus of an anti-CEA single-chain disulfide-stabilized Fv(scdsFv) antibody (single-chain-C-terminus/SEA, SC-C/SEA). The SC-C/SEA protein was expressed in Escherichia coli(E. coli), refolded, and purified on an immobilized Ni2+ affinity chromatography column. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) and Western blot analysis reveal that the target protein was expressed sufficiently. We used immunofluorescence assays to demonstrate that SC-C/SEA could bind specifically to human lung carcinoma cells(A549), but almost human uterine cervix cells(HeLa). We also used the L-lactate dehydrogenase(LDH) release assay to show that SC-C/SEA elicits a strong A549 tumor-specific cytotoxic T lymphocyte(CTL) response in vitro. The results suggest that SC-C/SEA shows specific activity against CEA-positive cells and has potential application in CEA-targeted cancer immunotherapy.

  19. Chimeric DNA Vaccines against ErbB2+ Carcinomas: From Mice to Humans

    International Nuclear Information System (INIS)

    DNA vaccination exploits a relatively simple and flexible technique to generate an immune response against microbial and tumor-associated antigens (TAAs). Its effectiveness is enhanced by the application of an electrical shock in the area of plasmid injection (electroporation). In our studies we exploited a sophisticated electroporation device approved for clinical use (Cliniporator, IGEA, Carpi, Italy). As the target antigen is an additional factor that dramatically modulates the efficacy of a vaccine, we selected ErbB2 receptor as a target since it is an ideal oncoantigen. It is overexpressed on the cell membrane by several carcinomas for which it plays an essential role in driving their progression. Most oncoantigens are self-tolerated molecules. To circumvent immune tolerance we generated two plasmids (RHuT and HuRT) coding for chimeric rat/human ErbB2 proteins. Their immunogenicity was compared in wild type mice naturally tolerant for mouse ErbB2, and in transgenic mice that are also tolerant for rat or human ErbB2. In several of these mice, RHuT and HuRT elicited a stronger anti-tumor response than plasmids coding for fully human or fully rat ErbB2. The ability of heterologous moiety to blunt immune tolerance could be exploited to elicit a significant immune response in patients. A clinical trial to delay the recurrence of ErbB2+ carcinomas of the oral cavity, oropharynx and hypopharynx is awaiting the approval of the Italian authorities

  20. Assessment of fetal cell chimerism in transgenic pig lines generated by Sleeping beauty transposition.

    Science.gov (United States)

    Garrels, Wiebke; Holler, Stephanie; Taylor, Ulrike; Herrmann, Doris; Niemann, Heiner; Ivics, Zoltan; Kues, Wilfried A

    2014-01-01

    Human cells migrate between mother and fetus during pregnancy and persist in the respective host for long-term after birth. Fetal microchimerism occurs also in twins sharing a common placenta or chorion. Whether microchimerism occurs in multiparous mammals such as the domestic pig, where fetuses have separate placentas and chorions, is not well understood. Here, we assessed cell chimerism in litters of wild-type sows inseminated with semen of transposon transgenic boars. Segregation of three independent monomeric transposons ensured an excess of transgenic over non-transgenic offspring in every litter. Transgenic siblings (n = 35) showed robust ubiquitous expression of the reporter transposon encoding a fluorescent protein, and provided an unique resource to assess a potential cell trafficking to non-transgenic littermates (n = 7) or mothers (n = 4). Sensitive flow cytometry, fluorescence microscopy, and real-time PCR provided no evidence for microchimerism in porcine littermates, or piglets and their mothers in both blood and solid organs. These data indicate that the epitheliochorial structure of the porcine placenta effectively prevents cellular exchange during gestation. PMID:24811124

  1. Pharmacologic suppression of target cell recognition by engineered T cells expressing chimeric T-cell receptors.

    Science.gov (United States)

    Alvarez-Vallina, L; Yañez, R; Blanco, B; Gil, M; Russell, S J

    2000-04-01

    Adoptive therapy with autologous T cells expressing chimeric T-cell receptors (chTCRs) is of potential interest for the treatment of malignancy. To limit possible T-cell-mediated damage to normal tissues that weakly express the targeted tumor antigen (Ag), we have tested a strategy for the suppression of target cell recognition by engineered T cells. Jurkat T cells were transduced with an anti-hapten chTCR tinder the control of a tetracycline-suppressible promoter and were shown to respond to Ag-positive (hapten-coated) but not to Ag-negative target cells. The engineered T cells were then reacted with hapten-coated target cells at different effector to target cell ratios before and after exposure to tetracycline. When the engineered T cells were treated with tetracycline, expression of the chTCR was greatly decreased and recognition of the hapten-coated target cells was completely suppressed. Tetracycline-mediated suppression of target cell recognition by engineered T cells may be a useful strategy to limit the toxicity of the approach to cancer gene therapy. PMID:10811469

  2. Design of Switchable Chimeric Antigen Receptor T Cells Targeting Breast Cancer.

    Science.gov (United States)

    Cao, Yu; Rodgers, David T; Du, Juanjuan; Ahmad, Insha; Hampton, Eric N; Ma, Jennifer S Y; Mazagova, Magdalena; Choi, Sei-Hyun; Yun, Hwa Young; Xiao, Han; Yang, Pengyu; Luo, Xiaozhou; Lim, Reyna K V; Pugh, Holly M; Wang, Feng; Kazane, Stephanie A; Wright, Timothy M; Kim, Chan Hyuk; Schultz, Peter G; Young, Travis S

    2016-06-20

    Chimeric antigen receptor T (CAR-T) cells have demonstrated promising results against hematological malignancies, but have encountered significant challenges in translation to solid tumors. To overcome these hurdles, we have developed a switchable CAR-T cell platform in which the activity of the engineered cell is controlled by dosage of an antibody-based switch. Herein, we apply this approach to Her2-expressing breast cancers by engineering switch molecules through site-specific incorporation of FITC or grafting of a peptide neo-epitope (PNE) into the anti-Her2 antibody trastuzumab (clone 4D5). We demonstrate that both switch formats can be readily optimized to redirect CAR-T cells (specific for the corresponding FITC or PNE) to Her2-expressing tumor cells, and afford dose-titratable activation of CAR-T cells ex vivo and complete clearance of the tumor in rodent xenograft models. This strategy may facilitate the application of immunotherapy to solid tumors by affording comparable efficacy with improved safety owing to switch-based control of the CAR-T response. PMID:27145250

  3. Chimeric calcium/calmodulin-dependent protein kinase in tobacco: differential regulation by calmodulin isoforms

    Science.gov (United States)

    Liu, Z.; Xia, M.; Poovaiah, B. W.

    1998-01-01

    cDNA clones of chimeric Ca2+/calmodulin-dependent protein kinase (CCaMK) from tobacco (TCCaMK-1 and TCCaMK-2) were isolated and characterized. The polypeptides encoded by TCCaMK-1 and TCCaMK-2 have 15 different amino acid substitutions, yet they both contain a total of 517 amino acids. Northern analysis revealed that CCaMK is expressed in a stage-specific manner during anther development. Messenger RNA was detected when tobacco bud sizes were between 0.5 cm and 1.0 cm. The appearance of mRNA coincided with meiosis and became undetectable at later stages of anther development. The reverse polymerase chain reaction (RT-PCR) amplification assay using isoform-specific primers showed that both of the CCaMK mRNAs were expressed in anther with similar expression patterns. The CCaMK protein expressed in Escherichia coli showed Ca2+-dependent autophosphorylation and Ca2+/calmodulin-dependent substrate phosphorylation. Calmodulin isoforms (PCM1 and PCM6) had differential effects on the regulation of autophosphorylation and substrate phosphorylation of tobacco CCaMK, but not lily CCaMK. The evolutionary tree of plant serine/threonine protein kinases revealed that calmodulin-dependent kinases form one subgroup that is distinctly different from Ca2+-dependent protein kinases (CDPKs) and other serine/threonine kinases in plants.

  4. Chimeric DNA Vaccines against ErbB2{sup +} Carcinomas: From Mice to Humans

    Energy Technology Data Exchange (ETDEWEB)

    Quaglino, Elena; Riccardo, Federica; Macagno, Marco; Bandini, Silvio; Cojoca, Rodica; Ercole, Elisabetta [Molecular Biotechnology Center, Department of Clinical and Biological Sciences, University of Turin, 10126 Turin (Italy); Amici, Augusto [Department of Molecular Cellular and Animal Biology, University of Camerino, 62032 Camerino (Italy); Cavallo, Federica, E-mail: federica.cavallo@unito.it [2 Department of Molecular Cellular and Animal Biology, University of Camerino, 62032 Camerino (Italy)

    2011-08-10

    DNA vaccination exploits a relatively simple and flexible technique to generate an immune response against microbial and tumor-associated antigens (TAAs). Its effectiveness is enhanced by the application of an electrical shock in the area of plasmid injection (electroporation). In our studies we exploited a sophisticated electroporation device approved for clinical use (Cliniporator, IGEA, Carpi, Italy). As the target antigen is an additional factor that dramatically modulates the efficacy of a vaccine, we selected ErbB2 receptor as a target since it is an ideal oncoantigen. It is overexpressed on the cell membrane by several carcinomas for which it plays an essential role in driving their progression. Most oncoantigens are self-tolerated molecules. To circumvent immune tolerance we generated two plasmids (RHuT and HuRT) coding for chimeric rat/human ErbB2 proteins. Their immunogenicity was compared in wild type mice naturally tolerant for mouse ErbB2, and in transgenic mice that are also tolerant for rat or human ErbB2. In several of these mice, RHuT and HuRT elicited a stronger anti-tumor response than plasmids coding for fully human or fully rat ErbB2. The ability of heterologous moiety to blunt immune tolerance could be exploited to elicit a significant immune response in patients. A clinical trial to delay the recurrence of ErbB2{sup +} carcinomas of the oral cavity, oropharynx and hypopharynx is awaiting the approval of the Italian authorities.

  5. Creation of chimeric human/rabbit APOBEC1 with HIV-1 restriction and DNA mutation activities

    Science.gov (United States)

    Ikeda, Terumasa; Ong, Eugene Boon Beng; Watanabe, Nobumoto; Sakaguchi, Nobuo; Maeda, Kazuhiko; Koito, Atsushi

    2016-01-01

    APOBEC1 (A1) proteins from lagomorphs and rodents have deaminase-dependent restriction activity against HIV-1, whereas human A1 exerts a negligible effect. To investigate these differences in the restriction of HIV-1 by A1 proteins, a series of chimeric proteins combining rabbit and human A1s was constructed. Homology models of the A1s indicated that their activities derive from functional domains that likely act in tandem through a dimeric interface. The C-terminal region containing the leucine-rich motif and the dimerization domains of rabbit A1 is important for its anti-HIV-1 activity. The A1 chimeras with strong anti-HIV-1 activity were incorporated into virions more efficiently than those without anti-HIV-1 activity, and exhibited potent DNA-mutator activity. Therefore, the C-terminal region of rabbit A1 is involved in both its packaging into the HIV-1 virion and its deamination activity against both viral cDNA and genomic RNA. This study identifies the novel molecular mechanism underlying the target specificity of A1.

  6. Homogeneized modeling of mineral dust emissions over Europe and Africa using the CHIMERE model

    Directory of Open Access Journals (Sweden)

    R. Briant

    2014-05-01

    Full Text Available In the region including Africa and Europe, the main part of mineral dust emissions is observed in Africa. The particles are thus transported towards Europe and constitute a non-negligible part of the surface aerosols measured and controlled in the framework of the European air quality legislation. The modelling of these African dust emissions fluxes and transport is widely studied and complex parameterizations are already used in regional to global model for this Sahara-Sahel region. In a lesser extent, mineral dust emissions occur locally in Europe, mainly over agricultural areas. Their modelling is generally poorly done or just ignored. But in some cases, this contribution may be important and may impact the European air quality budget. In this study, we propose an homogeneized calculations of mineral dust fluxes for Europe and Africa. For that, we extended the CHIMERE dust production model (DPM by using new soil and surface datasets, and the global aeolian roughness length dataset provided by GARLAP from microwave and visible satellite observations. This DPM is detailed along with academic tests case results and simulation on a real case results.

  7. Multiscale characterization of a chimeric biomimetic polypeptide for stem cell culture

    International Nuclear Information System (INIS)

    Mesenchymal stem cells have attracted great interest in the field of tissue engineering and regenerative medicine because of their multipotentiality and relative ease of isolation from adult tissues. The medical application of this cellular system requires the inclusion in a growth and delivery scaffold that is crucial for the clinical effectiveness of the therapy. In particular, the ideal scaffolding material should have the needed porosity and mechanical strength to allow a good integration with the surrounding tissues, but it should also assure high biocompatibility and full resorbability. For such a purpose, protein-inspired biomaterials and, in particular, elastomeric-derived polypeptides are playing a major role, in which they are expected to fulfil many of the biological and mechanical requirements. A specific chimeric protein, designed starting from elastin, resilin and collagen sequences, was characterized over different length scales. Single-molecule mechanics, aggregation properties and compatibility with human mesenchymal stem cells were tested, showing that the engineered compound is a good candidate as a stem cell scaffold to be used in tissue engineering applications. (paper)

  8. The developmental fate of green fluorescent mouse embryonic germ cells in chimeric embryos

    Institute of Scientific and Technical Information of China (English)

    XUXIN; SUMIOSUGANO; 等

    1999-01-01

    Primordial germ cells (PGCs),as precursors of mammalian germ lineage,have been gaining more attention as a new resource of pluripotent stem cells,which bring a great possibility to study developmental events of germ cell in vitro and at animal level.EG4 cells derived from 10.5 days post coitum (dpc) PGCs of 129/svJ strain mouse were established and maintained in an undifferentiated state.With an attempt to study the differentiation capability of EG4 cells with a reporter protein:green fluorescence protein,and the possible application of EG4 cells in the research of germ cell development,we have generated several EG4-GFP cell lines expressing enhanced green fluorescence protein (EGFP) and still maintaining typical characteristics of pluripotent stem cells.Then,the differentiation of EG4-GFP cells in vitro as well as their developmental fate in chimeric embryos which were produced by aggregating EG4-GFP cells to 8-cell stage embryos were studied.The results showed that EG4 cells carrying green fluorescence have a potential use in the research of germ cell development and other related studies.

  9. Current status and regulatory perspective of chimeric antigen receptor-modified T cell therapeutics.

    Science.gov (United States)

    Kim, Mi-Gyeong; Kim, Dongyoon; Suh, Soo-Kyung; Park, Zewon; Choi, Min Joung; Oh, Yu-Kyoung

    2016-04-01

    Chimeric antigen receptor-modified T cells (CAR-T) have emerged as a new modality for cancer immunotherapy due to their potent efficacy against terminal cancers. CAR-Ts are reported to exert higher efficacy than monoclonal antibodies and antibody-drug conjugates, and act via mechanisms distinct from T cell receptor-engineered T cells. These cells are constructed by transducing genes encoding fusion proteins of cancer antigen-recognizing single-chain Fv linked to intracellular signaling domains of T cell receptors. CAR-Ts are classified as first-, second- and third-generation, depending on the intracellular signaling domain number of T cell receptors. This review covers the current status of CAR-T research, including basic proof-of-concept investigations at the cell and animal levels. Currently ongoing clinical trials of CAR-T worldwide are additionally discussed. Owing to the lack of existing approved products, several unresolved concerns remain with regard to safety, efficacy and manufacturing of CAR-T, as well as quality control issues. In particular, the cytokine release syndrome is the major side-effect impeding the successful development of CAR-T in clinical trials. Here, we have addressed the challenges and regulatory perspectives of CAR-T therapy. PMID:26895243

  10. Performance-enhancing drugs: design and production of redirected chimeric antigen receptor (CAR) T cells.

    Science.gov (United States)

    Levine, B L

    2015-03-01

    Performance enhancement of the immune system can now be generated through ex vivo gene modification of T cells in order to redirect native specificity to target tumor antigens. This approach combines the specificity of antibody therapy, the expanded response of cellular therapy and the memory activity of vaccine therapy. Recent clinical trials of chimeric antigen receptor (CAR) T cells directed toward CD19 as a stand-alone therapy have shown sustained complete responses in patients with acute lymphoblastic leukemia and chronic lymphocytic leukemia. As these drug products are individually derived from a patient's own cells, a different manufacturing approach is required for this kind of personalized therapy compared with conventional drugs. Key steps in the CAR T-cell manufacturing process include the selection and activation of isolated T cells, transduction of T cells to express CARs, ex vivo expansion of modified T cells and cryopreservation in infusible media. In this review, the steps involved in isolating, genetically modifying and scaling-out the CAR T cells for use in a clinical setting are described in the context of in-process and release testing and regulatory standards. PMID:25675873

  11. Chimeric Antigen Receptor-Modified T Cells for Solid Tumors: Challenges and Prospects

    Directory of Open Access Journals (Sweden)

    Yelei Guo

    2016-01-01

    Full Text Available Recent studies have highlighted the successes of chimeric antigen receptor-modified T- (CART- cell-based therapy for B-cell malignancies, and early phase clinical trials have been launched in recent years. The few published clinical studies of CART cells in solid tumors have addressed safety and feasibility, but the clinical outcome data are limited. Although antitumor effects were confirmed in vitro and in animal models, CART-cell-based therapy still faces several challenges when directed towards solid tumors, and it has been difficult to achieve the desired outcomes in clinical practice. Many studies have struggled to improve the clinical responses to and benefits of CART-cell treatment of solid tumors. In this review, the status quo of CART cells and their clinical applications for solid tumors will be summarized first. Importantly, we will suggest improvements that could increase the therapeutic effectiveness of CART cells for solid tumors and their future clinical applications. These interventions will make treatment with CART cells an effective and routine therapy for solid tumors.

  12. Diverse hematological malignancies including hodgkin-like lymphomas develop in chimeric MHC class II transgenic mice.

    Directory of Open Access Journals (Sweden)

    Silke H Raffegerst

    Full Text Available A chimeric HLA-DR4-H2-E (DR4 homozygous transgenic mouse line spontaneously develops diverse hematological malignancies with high frequency (70%. The majority of malignancies were distributed equally between T and B cell neoplasms and included lymphoblastic T cell lymphoma (LTCL, lymphoblastic B cell lymphoma (LBCL, diffuse large B cell lymphoma (DLBCL, the histiocyte/T cell rich variant of DLBCL (DLBCL-HA/T cell rich DLBCL, splenic marginal zone lymphoma (SMZL, follicular B cell lymphoma (FBL and plasmacytoma (PCT. Most of these neoplasms were highly similar to human diseases. Also, some non-lymphoid malignancies such as acute myeloid leukemia (AML and histiocytic sarcoma were found. Interestingly, composite lymphomas, including Hodgkin-like lymphomas, were also detected that had CD30(+ Hodgkin/Reed-Sternberg (H/RS-like cells, representing a tumor type not previously described in mice. Analysis of microdissected H/RS-like cells revealed their origin as germinal center B cells bearing somatic hypermutations and, in some instances, crippled mutations, as described for human Hodgkin lymphoma (HL. Transgene integration in an oncogene was excluded as an exclusive driving force of tumorigenesis and age-related lymphoma development suggests a multi-step process. Thus, this DR4 line is a useful model to investigate common molecular mechanisms that may contribute to important neoplastic diseases in man.

  13. Modification of chimeric (2S, 3S)-butanediol dehydrogenase based on structural information.

    Science.gov (United States)

    Shimegi, Tomohito; Mochizuki, Kaito; Oyama, Takuji; Ohtsuki, Takashi; Kusunoki, Masami; Ui, Sadaharu

    2014-01-01

    A chimeric (2S, 3S)-butanediol dehydrogenase (cLBDH) was engineered to have the strict (S)-configuration specificity of the (2S, 3S)-BDH (BsLBDH) derived from Brevibacterium saccharolyticum as well as the enzymatic stability of the (2R, 3S)-BDH (KpMBDH) from Klebsiella pneumonia by swapping the domains of two native BDHs. However, while cLBDH possesses the stability, it lacks the specificity. In order to assist in the design a BDH having strict substrate specificity, an X-ray structural analysis of a cLBDH crystal was conducted at 1.58 Å. The results obtained show some readily apparent differences around the active sites of cLBDH and BsLBDH. Based on this structural information, a novel (2S, 3S)-BDH having a preferred specificity was developed by introducing a V254L mutation into cLBDH. The influence of this mutation on the stability of cLBDH was not evaluated. Nevertheless, the technique described herein is an effective method for the production of a tailor-made BDH. PMID:25612804

  14. Nanoparticles of cationic chimeric peptide and sodium polyacrylate exhibit striking antinociception activity at lower dose.

    Science.gov (United States)

    Gupta, Kshitij; Singh, Vijay P; Kurupati, Raj K; Mann, Anita; Ganguli, Munia; Gupta, Yogendra K; Singh, Yogendra; Saleem, Kishwar; Pasha, Santosh; Maiti, Souvik

    2009-02-20

    The current study investigates the performance of polyelectrolyte complexes based nanoparticles in improving the antinociceptive activity of cationic chimeric peptide-YFa at lower dose. Size, Zeta potential and morphology of the nanoparticles were determined. Size of the nanoparticles decreases and zeta potential increases with concomitant increase in charge ratio (Z(+/-)). The nanoparticles at Z(+/-)12 are spherical with 70+/-7 nm diameter in AFM and displayed positive surface charge and similar sizes (83+/-8 nm) by Zetasizer. The nanoparticles of Z(+/-) 12 are used in this study. Cytotoxicity by MTT assay on three different mammalian cell lines (liver, neuronal and kidney) revealed lower toxicity of nanoparticles. Hematological parameters were also not affected by nanoparticles compared to normal counts of water treated control group. Nanoparticles containing 10 mg/kg YFa produced increased antinociception, approximately 36%, in tail-flick latency test in mice, whereas the neat peptide at the same concentration did not show any antinociception activity. This enhancement in activity is attributed to the nanoparticle associated protection of peptide from proteolytic degradation. In vitro peptide release study in plasma also supported the antinociception profile of nanoparticles. Thus, our results suggest of a potential nanoparticle delivery system for cationic peptide drug candidates for improving their stability and bioavailability. PMID:19014986

  15. Subalpine Pyrenees received higher nitrogen deposition than predicted by EMEP and CHIMERE chemistry-transport models

    Science.gov (United States)

    Boutin, Marion; Lamaze, Thierry; Couvidat, Florian; Pornon, André

    2015-08-01

    Deposition of reactive nitrogen (N) from the atmosphere is expected to be the third greatest driver of biodiversity loss by the year 2100. Chemistry-transport models are essential tools to estimate spatially explicit N deposition but the reliability of their predictions remained to be validated in mountains. We measured N deposition and air concentration over the subalpine Pyrenees. N deposition was found to range from 797 to 1,463 mg N m-2 year-1. These values were higher than expected from model predictions, especially for nitrate, which exceeded the estimations of EMEP by a factor of 2.6 and CHIMERE by 3.6. Our observations also displayed a reversed reduced-to-oxidized ratio in N deposition compared with model predictions. The results highlight that the subalpine Pyrenees are exposed to higher levels of N deposition than expected according to standard predictions and that these levels exceed currently recognized critical loads for most high-elevation habitats. Our study reveals a need to improve the evaluation of N deposition in mountains which are home to a substantial and original part of the world’s biodiversity.

  16. Design and development of therapies using chimeric antigen receptor-expressing T cells.

    Science.gov (United States)

    Dotti, Gianpietro; Gottschalk, Stephen; Savoldo, Barbara; Brenner, Malcolm K

    2014-01-01

    Investigators developed chimeric antigen receptors (CARs) for expression on T cells more than 25 years ago. When the CAR is derived from an antibody, the resultant cell should combine the desirable targeting features of an antibody (e.g. lack of requirement for major histocompatibility complex recognition, ability to recognize non-protein antigens) with the persistence, trafficking, and effector functions of a T cell. This article describes how the past two decades have seen a crescendo of research which has now begun to translate these potential benefits into effective treatments for patients with cancer. We describe the basic design of CARs, describe how antigenic targets are selected, and the initial clinical experience with CAR-T cells. Our review then describes our own and other investigators' work aimed at improving the function of CARs and reviews the clinical studies in hematological and solid malignancies that are beginning to exploit these approaches. Finally, we show the value of adding additional engineering features to CAR-T cells, irrespective of their target, to render them better suited to function in the tumor environment, and discuss how the safety of these heavily modified cells may be maintained. PMID:24329793

  17. Virus Movement Maintains Local Virus Population Diversity

    Energy Technology Data Exchange (ETDEWEB)

    J. Snyder; B. Wiedenheft; M. Lavin; F. Roberto; J. Spuhler; A. Ortmann; T. Douglas; M. Young

    2007-11-01

    Viruses are the largest reservoir of genetic material on the planet, yet little is known about the population dynamics of any virus within its natural environment. Over a 2-year period, we monitored the diversity of two archaeal viruses found in hot springs within Yellowstone National Park (YNP). Both temporal phylogeny and neutral biodiversity models reveal that virus diversity in these local environments is not being maintained by mutation but rather by high rates of immigration from a globally distributed metacommunity. These results indicate that geographically isolated hot springs are readily able to exchange viruses. The importance of virus movement is supported by the detection of virus particles in air samples collected over YNP hot springs and by their detection in metacommunity sequencing projects conducted in the Sargasso Sea. Rapid rates of virus movement are not expected to be unique to these archaeal viruses but rather a common feature among virus metacommunities. The finding that virus immigration rather than mutation can dominate community structure has significant implications for understanding virus circulation and the role that viruses play in ecology and evolution by providing a reservoir of mobile genetic material.

  18. Engineering HIV-1-resistant T-cells from short-hairpin RNA-expressing hematopoietic stem/progenitor cells in humanized BLT mice.

    Directory of Open Access Journals (Sweden)

    Gene-Errol E Ringpis

    Full Text Available Down-regulation of the HIV-1 coreceptor CCR5 holds significant potential for long-term protection against HIV-1 in patients. Using the humanized bone marrow/liver/thymus (hu-BLT mouse model which allows investigation of human hematopoietic stem/progenitor cell (HSPC transplant and immune system reconstitution as well as HIV-1 infection, we previously demonstrated stable inhibition of CCR5 expression in systemic lymphoid tissues via transplantation of HSPCs genetically modified by lentiviral vector transduction to express short hairpin RNA (shRNA. However, CCR5 down-regulation will not be effective against existing CXCR4-tropic HIV-1 and emergence of resistant viral strains. As such, combination approaches targeting additional steps in the virus lifecycle are required. We screened a panel of previously published shRNAs targeting highly conserved regions and identified a potent shRNA targeting the R-region of the HIV-1 long terminal repeat (LTR. Here, we report that human CD4(+ T-cells derived from transplanted HSPC engineered to co-express shRNAs targeting CCR5 and HIV-1 LTR are resistant to CCR5- and CXCR4- tropic HIV-1-mediated depletion in vivo. Transduction with the combination vector suppressed CXCR4- and CCR5- tropic viral replication in cell lines and peripheral blood mononuclear cells in vitro. No obvious cytotoxicity or interferon response was observed. Transplantation of combination vector-transduced HSPC into hu-BLT mice resulted in efficient engraftment and subsequent stable gene marking and CCR5 down-regulation in human CD4(+ T-cells within peripheral blood and systemic lymphoid tissues, including gut-associated lymphoid tissue, a major site of robust viral replication, for over twelve weeks. CXCR4- and CCR5- tropic HIV-1 infection was effectively inhibited in hu-BLT mouse spleen-derived human CD4(+ T-cells ex vivo. Furthermore, levels of gene-marked CD4(+ T-cells in peripheral blood increased despite systemic infection with either

  19. Synthesis and characterization of human recombinant thyrotropin (rec-hTSH) with a chimeric β-subunit (rec-hTSHβ-CTPE hCGβ)

    International Nuclear Information System (INIS)

    Recombinant hTSH is now successfully being used in clinical studies of thyroid cancer. Because of its therapeutic potential, we have constructed a longer acting analog of hTSH by fusing the carboxy terminal extension peptide (CTEP) of hCGβ onto hTSHβ. When coexpressed either with α-subunit complementary DNA or α-minigene in African green monkey (Cos-7) and human embryonic kidney (293) cells, the chimera was fully bioactive in vitro and exhibited enhanced in vivo potency associated with a prolonged plasma half-life. The addition of 29 amino acids with 4 O-linked oligosaccharide chains did not affect the assembly and secretion of chimeric TSH. Wild type (WT) and chimeric hTSH secreted by Cos-7 and 293 cells displayed wide differences in their plasma half-lives, presumably due to the difference in the terminal sialic acid and sulfate of their oligosaccharide chains. Chimeric and WT hTSH secreted by both cell lines demonstrated similar bioactivity in cAMP production, with some differences in [3 H]-thymidine incorporation. Chimeric hTSH secreted by Cos-7 appears to be more active than that secreted by 293 cells, as judged by growth assay. Cos-7 produced chimeric hTSH showed the maximum increase in half-life, indicating the importance of sialic acid in prolonging half-life and in vivo potency. Sulfation of both subunits, predominantly β and to a lesser extent α, appears to be responsible, at least in part, for the increased metabolic clearance of WT and chimeric TSH secreted by 293 cells. Apart from its therapeutic potential, chimeric TSH produced in various cell lines can be used as a tool to delineate the roles of sulfate and sialic acid in the in vivo clearance and, thereby in the in vivo bioactivity. (author). 104 refs., 23 figs., 3 tabs

  20. A fast and simple approach for the simultaneous detection of hematopoietic chimerism, NPM1, and FLT3-ITD mutations after allogeneic stem cell transplantation.

    Science.gov (United States)

    Waterhouse, Miguel; Bertz, Hartmut; Finke, Juergen

    2014-02-01

    Hematopoietic chimerism can be used as a tool for patient management after allogeneic hematopoietic stem cell transplantation (HSCT). An increase in the proportion of recipient cells after transplantation is strongly associated with relapse in chronic myeloid leukemia. However, in acute myeloid leukemia (AML) the significance of increasing mixed chimerism (MC) as a predictive marker for relapse is less clear. Several mutations frequently found in AML have been employed for minimal residual disease detection and relapse prediction. Therefore, a combined analysis of hematopoietic chimerism and of the molecular aberrations found in AML could be used to improve MC characterization. We developed a multiplex PCR for use in the simultaneous detection of hematopoietic chimerism and mutations in nucleophosmin (NPM1) and fms-like tyrosine kinase-3 internal tandem duplication (FLT3-ITD). A total of 303 samples from 20 AML patients were analyzed after HSCT. The microsatellite markers used for hematopoietic chimerism detection were D1S80, D7S1517, D4S2366, THO1, and SE33. A total of 149 samples from 18 patients showed MC with a mean detection time of 9.7 months. From the 18 patients with MC, in 6 of the patients, no FLT3-ITD or NPM1 mutation was found at any time point tested, and these patients remained in complete hematological remission. In 12 patients with MC, FLT3-ITD and NPM1 mutations were found, and these patients showed signs of hematological relapse. Our combined analysis of NPM1/FLT3-ITD mutations and hematopoietic chimerism improved the characterization of patients with MC after HSCT. The present approach may be further expanded by combining additional mutations found in AML with hematopoietic chimerism detection. PMID:23907410

  1. Intragenotypic JFH1 based recombinant hepatitis C virus produces high levels of infectious particles but causes increased cell death

    DEFF Research Database (Denmark)

    Mateu, Guaniri; Donis, Ruben O; Wakita, Takaji;

    2008-01-01

    into the JFH1 infectious clone. All genomes produced high levels of intracellular HCV RNA and NS3 protein in Huh-7.5 transfected cells. However, JFH1 genomes containing J6 sequences from C to E2 (CE2) or C to p7 (Cp7) secreted up to 100-fold more infectious HCV particles than the parental JFH1 clone......The full-length hepatitis C virus (HCV) JFH1 genome (genotype 2a) produces moderate titers of infectious particles in cell culture but the optimal determinants required for virion production are unclear. It has been shown that intragenotypic recombinants encoding core to NS2 from J6CF in the...... of the chimeric junction. Moreover, NTRNS2 a chimeric virus equivalent to the previously reported FL-J6/JFH chimera, showed a 10-fold enhancement of virus titers compared to CNS2. NTRNS2 differs from CNS2 by three nucleotide differences residing in the 5' NTR and core coding sequence and all three...

  2. Chimeric toxins inhibit growth of primary oral squamous cell carcinoma cells.

    Science.gov (United States)

    Bachran, Christopher; Heisler, Iring; Bachran, Diana; Dassler, Katrin; Ervens, Jürgen; Melzig, Matthias F; Fuchs, Hendrik

    2008-02-01

    Treatment of oral squamous cell carcinoma (OSCC) is currently based on surgery and radiotherapy. Prolongation of the survival time of patients with progressing tumors is infrequently achieved. To improve the therapeutic options, targeted therapies are a favorable alternative. Therefore, we analyzed the effect of a chimeric toxin (CT) named SE consisting of the epidermal growth factor and the plant protein toxin saporin from Saponaria officinalis. A second construct (SA2E) additionally contains a peptidic adapter designed to enhance efficacy of the CT in vivo and to reduce side effects. The IC(50) values for an OSCC cell line (BHY) were 0.27 nM and 0.73 nM for SE and SA2E, respectively, while fibroblasts remained unaffected. To investigate primary tumor cells, we developed a technique to analyze freshly prepared OSCC cells of 28 patients in a stem cell assay directly after surgery. Cells were treated for 1 h with the CTs, subsequently seeded into soft agar and colony growth determined after 1-2 weeks In spite of the short time of CT incubation, the amount of colonies was reduced to about 78% by 10 nM and to 69% by 100 nM of either toxin. A combined application of 10 nM SA2E with a saponin from Gypsophila paniculata reduced the amount of surviving cells to 68%. The results demonstrate the impact of the CTs on OSCC cells and depict that the stem cell assay is suitable to determine the potential of anti-tumor drugs before studies in vivo will be initiated. PMID:18059188

  3. Design of a novel chimeric tissue plasminogen activator with favorable Vampire bat plasminogen activator properties.

    Science.gov (United States)

    Kazemali, MohammadReza; Majidzadeh-A, Keivan; Sardari, Soroush; Saadatirad, Amir Hossein; Khalaj, Vahid; Zarei, Najmeh; Barkhordari, Farzaneh; Adeli, Ahmad; Mahboudi, Fereidoun

    2014-12-01

    Fibrinolytic agents are widely used in treatment of the thromboembolic disorders. The new generations like recombinant tissue plasminogen activator (t-PA, alteplase) are not showing promising results in clinical practice in spite of displaying specific binding to fibrin in vitro. Vampire bat plasminogen activator (b-PA) is a plasminogen activator with higher fibrin affinity and specificity in comparison to t-PA resulting in reduced probability of hemorrhage. b-PA is also resistant to plasminogen activator inhibitor-1 (PAI-1) showing higher half-life compared to other variants of t-PA. However, its non-human origin was a driving force to design a human t-PA with favorable properties of b-PA. In the present study, we designed a chimeric t-PA with desirable b-PA properties and this new molecule was called as CT-b. The construct was prepared through kringle 2 domain removal and replacement of t-PA finger domain with b-PA one. In addition, the KHRR sequence at the initial part of protease domain was replaced by four alanine residues. The novel construct was integrated in Pichia pastoris genome by electroporation. Catalytic activity was investigated in the presence and absence of fibrin. The purified protein was analyzed by western blot. Fibrin binding and PAI resistance assays were also conducted. The activity of the recombinant protein in the presence of fibrin was 1560 times more than its activity in the absence of fibrin, showing its higher specificity to fibrin. The fibrin binding of CT-b was 1.2 fold more than t-PA. In addition, it was inhibited by PAI enzyme 44% less than t-PA. Although the presented data demonstrate a promising in vitro activity, more in vivo studies are needed to confirm the therapeutic advantage of this novel plasminogen activator. PMID:25442953

  4. Porcine Pluripotent Stem Cells Derived from IVF Embryos Contribute to Chimeric Development In Vivo.

    Directory of Open Access Journals (Sweden)

    Binghua Xue

    Full Text Available Although the pig is considered an important model of human disease and an ideal animal for the preclinical testing of cell transplantation, the utility of this model has been hampered by a lack of genuine porcine embryonic stem cells. Here, we derived a porcine pluripotent stem cell (pPSC line from day 5.5 blastocysts in a newly developed culture system based on MXV medium and a 5% oxygen atmosphere. The pPSCs had been passaged more than 75 times over two years, and the morphology of the colony was similar to that of human embryonic stem cells. Characterization and assessment showed that the pPSCs were alkaline phosphatase (AKP positive, possessed normal karyotypes and expressed classic pluripotent markers, including OCT4, SOX2 and NANOG. In vitro differentiation through embryonic body formation and in vivo differentiation via teratoma formation in nude mice demonstrated that the pPSCs could differentiate into cells of the three germ layers. The pPSCs transfected with fuw-DsRed (pPSC-FDs could be passaged with a stable expression of both DsRed and pluripotent markers. Notably, when pPSC-FDs were used as donor cells for somatic nuclear transfer, 11.52% of the reconstructed embryos developed into blastocysts, which was not significantly different from that of the reconstructed embryos derived from porcine embryonic fibroblasts. When pPSC-FDs were injected into day 4.5 blastocysts, they became involved in the in vitro embryonic development and contributed to the viscera of foetuses at day 50 of pregnancy as well as the developed placenta after the chimeric blastocysts were transferred into recipients. These findings indicated that the pPSCs were porcine pluripotent cells; that this would be a useful cell line for porcine genetic engineering and a valuable cell line for clarifying the molecular mechanism of pluripotency regulation in pigs.

  5. RNA-guided Transcriptional Regulation in Plants via dCas9 Chimeric Proteins

    KAUST Repository

    Baazim, Hatoon

    2014-05-01

    Developing targeted genome regulation approaches holds much promise for accelerating trait discovery and development in agricultural biotechnology. Clustered Regularly Interspaced Palindromic Repeats (CRISPRs)/CRISPR associated (Cas) system provides bacteria and archaea with an adaptive molecular immunity mechanism against invading nucleic acids through phages and conjugative plasmids. The type II CRISPR/Cas system has been adapted for genome editing purposes across a variety of cell types and organisms. Recently, the catalytically inactive Cas9 (dCas9) protein combined with guide RNAs (gRNAs) were used as a DNA-targeting platform to modulate the expression patterns in bacterial, yeast and human cells. Here, we employed this DNA-targeting system for targeted transcriptional regulation in planta by developing chimeric dCas9-based activators and repressors. For example, we fused to the C-terminus of dCas9 with the activation domains of EDLL and TAL effectors, respectively, to generate transcriptional activators, and the SRDX repression domain to generate transcriptional repressor. Our data demonstrate that the dCas9:EDLL and dCas9:TAD activators, guided by gRNAs complementary to promoter elements, induce strong transcriptional activation on episomal targets in plant cells. Moreover, our data suggest that the dCas9:SRDX repressor and the dCas9:EDLL and dCas9:TAD activators are capable of markedly repressing or activating, respectively, the transcription of an endogenous genomic target. Our data indicate that the CRISPR/dCas9:TFs DNA targeting system can be used in plants as a functional genomic tool and for biotechnological applications.

  6. Making Better Chimeric Antigen Receptors for Adoptive T-cell Therapy.

    Science.gov (United States)

    Maus, Marcela V; June, Carl H

    2016-04-15

    Chimeric antigen receptors (CAR) are engineered fusion proteins constructed from antigen recognition, signaling, and costimulatory domains that can be expressed in cytotoxic T cells with the purpose of reprograming the T cells to specifically target tumor cells. CAR T-cell therapy uses gene transfer technology to reprogram a patient's own T cells to stably express CARs, thereby combining the specificity of an antibody with the potent cytotoxic and memory functions of a T cell. In early-phase clinical trials, CAR T cells targeting CD19 have resulted in sustained complete responses within a population of otherwise refractory patients with B-cell malignancies and, more specifically, have shown complete response rates of approximately 90% in patients with relapsed or refractory acute lymphoblastic leukemia. Given this clinical efficacy, preclinical development of CAR T-cell therapy for a number of cancer indications has been actively investigated, and the future of the CAR T-cell field is extensive and dynamic. Several approaches to increase the feasibility and safety of CAR T cells are currently being explored, including investigation into the mechanisms regulating the persistence of CAR T cells. In addition, numerous early-phase clinical trials are now investigating CAR T-cell therapy beyond targeting CD19, especially in solid tumors. Trials investigating combinations of CAR T cells with immune checkpoint blockade therapies are now beginning and results are eagerly awaited. This review evaluates several of the ongoing and future directions of CAR T-cell therapy.Clin Cancer Res; 22(8); 1875-84. ©2016 AACR SEE ALL ARTICLES IN THIS CCR FOCUS SECTION, "OPPORTUNITIES AND CHALLENGES IN CANCER IMMUNOTHERAPY". PMID:27084741

  7. Calcium-stimulated autophosphorylation site of plant chimeric calcium/calmodulin-dependent protein kinase

    Science.gov (United States)

    Sathyanarayanan, P. V.; Siems, W. F.; Jones, J. P.; Poovaiah, B. W.

    2001-01-01

    The existence of two molecular switches regulating plant chimeric Ca(2+)/calmodulin-dependent protein kinase (CCaMK), namely the C-terminal visinin-like domain acting as Ca(2+)-sensitive molecular switch and calmodulin binding domain acting as Ca(2+)-stimulated autophosphorylation-sensitive molecular switch, has been described (Sathyanarayanan, P. V., Cremo, C. R., and Poovaiah, B. W. (2000) J. Biol. Chem. 275, 30417-30422). Here we report the identification of Ca(2+)-stimulated autophosphorylation site of CCaMK by matrix-assisted laser desorption ionization time of flight-mass spectrometry. Thr(267) was confirmed as the Ca(2+)-stimulated autophosphorylation site by post-source decay experiments and by site-directed mutagenesis. The purified T267A mutant form of CCaMK did not show Ca(2+)-stimulated autophosphorylation, autophosphorylation-dependent variable calmodulin affinity, or Ca(2+)/calmodulin stimulation of kinase activity. Sequence comparison of CCaMK from monocotyledonous plant (lily) and dicotyledonous plant (tobacco) suggests that the autophosphorylation site is conserved. This is the first identification of a phosphorylation site specifically responding to activation by second messenger system (Ca(2+) messenger system) in plants. Homology modeling of the kinase and calmodulin binding domain of CCaMK with the crystal structure of calcium/calmodulin-dependent protein kinase 1 suggests that the Ca(2+)-stimulated autophosphorylation site is located on the surface of the kinase and far from the catalytic site. Analysis of Ca(2+)-stimulated autophosphorylation with increasing concentration of CCaMK indicates the possibility that the Ca(2+)-stimulated phosphorylation occurs by an intermolecular mechanism.

  8. Autophosphorylation-dependent inactivation of plant chimeric calcium/calmodulin-dependent protein kinase

    Science.gov (United States)

    Sathyanarayanan, P. V.; Poovaiah, B. W.

    2002-01-01

    Chimeric calcium/calmodulin dependent protein kinase (CCaMK) is characterized by the presence of a visinin-like Ca(2+)-binding domain unlike other known calmodulin- dependent kinases. Ca(2+)-Binding to the visinin-like domain leads to autophosphorylation and changes in the affinity for calmodulin [Sathyanarayanan P.V., Cremo C.R. & Poovaiah B.W. (2000) J. Biol. Chem. 275, 30417-30422]. Here, we report that the Ca(2+)-stimulated autophosphorylation of CCaMK results in time-dependent loss of enzyme activity. This time-dependent loss of activity or self-inactivation due to autophosphorylation is also dependent on reaction pH and ATP concentration. Inactivation of the enzyme resulted in the formation of a sedimentable enzyme due to self-association. Specifically, autophosphorylation in the presence of 200 microm ATP at pH 7.5 resulted in the formation of a sedimentable enzyme with a 33% loss in enzyme activity. Under similar conditions at pH 6.5, the enzyme lost 67% of its activity and at pH 8.5, 84% enzyme activity was lost. Furthermore, autophosphorylation at either acidic or alkaline reaction pH lead to the formation of a sedimentable enzyme. Transmission electron microscopic studies on autophosphorylated kinase revealed particles that clustered into branched complexes. The autophosphorylation of wild-type kinase in the presence of AMP-PNP (an unhydrolyzable ATP analog) or the autophosphorylation-site mutant, T267A, did not show formation of branched complexes under the electron microscope. Autophosphorylation- dependent self-inactivation may be a mechanism of modulating the signal transduction pathway mediated by CCaMK.

  9. Developmental regulation of the gene for chimeric calcium/calmodulin-dependent protein kinase in anthers

    Science.gov (United States)

    Poovaiah, B. W.; Xia, M.; Liu, Z.; Wang, W.; Yang, T.; Sathyanarayanan, P. V.; Franceschi, V. R.

    1999-01-01

    Chimeric Ca(2+)/calmodulin-dependent protein kinase (CCaMK) was cloned from developing anthers of lily (Lilium longiflorum Thumb. cv. Nellie White) and tobacco (Nicotiana tabacum L. cv. Xanthi). Previous biochemical characterization and structure/function studies had revealed that CCaMK has dual modes of regulation by Ca(2+) and Ca(2+)/calmodulin. The unique structural features of CCaMK include a catalytic domain, a calmodulin-binding domain, and a neural visinin-like Ca(2+)-binding domain. The existence of these three features in a single polypeptide distinguishes it from other kinases. Western analysis revealed that CCaMK is expressed in a stage-specific manner in developing anthers. Expression of CCaMK was first detected in pollen mother cells and continued to increase, reaching a peak around the tetrad stage of meiosis. Following microsporogenesis, CCaMK expression rapidly decreased and at later stages of microspore development, no expression was detected. A tobacco genomic clone of CCaMK was isolated and transgenic tobacco plants were produced carrying the CCaMK promoter fused to the beta-glucuronidase reporter gene. Both CCaMK mRNA and protein were detected in the pollen sac and their localizations were restricted to the pollen mother cells and tapetal cells. Consistent results showing a stage-specific expression pattern were obtained by beta-glucuronidase analysis, in-situ hybridization and immunolocalization. The stage- and tissue-specific appearance of CCaMK in anthers suggests that it could play a role in sensing transient changes in free Ca(2+) concentration in target cells, thereby controlling developmental events in the anther.

  10. Partitioning of genetically distinct cell populations in chimeric juveniles of the sponge Amphimedon queenslandica.

    Science.gov (United States)

    Gauthier, Marie; Degnan, Bernard M

    2008-01-01

    Natural chimerism, the fusion between genetically distinct conspecifics, is a process known to occur in various marine benthic invertebrates. Sponges (phylum Porifera) have proven to be a useful model to study the origin and evolution of allorecognition. Like some other invertebrates, they display an ontogenetic shift in their allorecognition response: genetically different individuals can fuse during early development, but, in most instances, not as adults. However, there is a limited understanding of the cellular organisation of sponge chimeras and the onset of this allorecognition response, which prevents integration of incompatible genotypes. Here we follow the behaviours and fates of cells derived from genetically distinct larvae of the demosponge Amphimedon queenslandica that have fused together at metamorphosis. By labelling individual larvae with different fluorescent dyes, we can follow cell movement in the postlarval chimeras. We observed that cells from the two individuals readily mixed for 2 weeks after the initial fusion. After that time, differently labelled cells began to sort into different postlarval cellular territories, with one lineage giving rise to choanocytes and the other to pinacocytes and cells of the mesohyl. These results suggest that a rapid ontogenetic shift in the allogeneic response of A. queenslandica occurs about 2 weeks after the initiation of metamorphosis and that the molecular basis of this response is also involved in creating differential cell affinities that underlie the construction of the sponge body plan. Compatible with this proposition is the observation that cells from postlarvae that are allowed to develop for 2 weeks before contact do not fuse and form a distinct boundary between genotypes. The successful chimeras remained stable for the duration of the experiment (3 weeks) raising the possibility that reproductive chimeras might persist in the natural environment, with a single genotype giving rise to germ cells

  11. Identification of chimeric antigen receptors that mediate constitutive or inducible proliferation of T cells.

    Science.gov (United States)

    Frigault, Matthew J; Lee, Jihyun; Basil, Maria Ciocca; Carpenito, Carmine; Motohashi, Shinichiro; Scholler, John; Kawalekar, Omkar U; Guedan, Sonia; McGettigan, Shannon E; Posey, Avery D; Ang, Sonny; Cooper, Laurence J N; Platt, Jesse M; Johnson, F Brad; Paulos, Chrystal M; Zhao, Yangbing; Kalos, Michael; Milone, Michael C; June, Carl H

    2015-04-01

    This study compared second-generation chimeric antigen receptors (CAR) encoding signaling domains composed of CD28, ICOS, and 4-1BB (TNFRSF9). Here, we report that certain CARs endow T cells with the ability to undergo long-term autonomous proliferation. Transduction of primary human T cells with lentiviral vectors encoding some of the CARs resulted in sustained proliferation for up to 3 months following a single stimulation through the T-cell receptor (TCR). Sustained numeric expansion was independent of cognate antigen and did not require the addition of exogenous cytokines or feeder cells after a single stimulation of the TCR and CD28. Results from gene array and functional assays linked sustained cytokine secretion and expression of T-bet (TBX21), EOMES, and GATA-3 to the effect. Sustained expression of the endogenous IL2 locus has not been reported in primary T cells. Sustained proliferation was dependent on CAR structure and high expression, the latter of which was necessary but not sufficient. The mechanism involves constitutive signaling through NF-κB, AKT, ERK, and NFAT. The propagated CAR T cells retained a diverse TCR repertoire, and cellular transformation was not observed. The CARs with a constitutive growth phenotype displayed inferior antitumor effects and engraftment in vivo. Therefore, the design of CARs that have a nonconstitutive growth phenotype may be a strategy to improve efficacy and engraftment of CAR T cells. The identification of CARs that confer constitutive or nonconstitutive growth patterns may explain observations that CAR T cells have differential survival patterns in clinical trials. PMID:25600436

  12. Porcine Pluripotent Stem Cells Derived from IVF Embryos Contribute to Chimeric Development In Vivo

    Science.gov (United States)

    Xue, Binghua; Li, Yan; He, Yilong; Wei, Renyue; Sun, Ruizhen; Yin, Zhi; Bou, Gerelchimeg; Liu, Zhonghua

    2016-01-01

    Although the pig is considered an important model of human disease and an ideal animal for the preclinical testing of cell transplantation, the utility of this model has been hampered by a lack of genuine porcine embryonic stem cells. Here, we derived a porcine pluripotent stem cell (pPSC) line from day 5.5 blastocysts in a newly developed culture system based on MXV medium and a 5% oxygen atmosphere. The pPSCs had been passaged more than 75 times over two years, and the morphology of the colony was similar to that of human embryonic stem cells. Characterization and assessment showed that the pPSCs were alkaline phosphatase (AKP) positive, possessed normal karyotypes and expressed classic pluripotent markers, including OCT4, SOX2 and NANOG. In vitro differentiation through embryonic body formation and in vivo differentiation via teratoma formation in nude mice demonstrated that the pPSCs could differentiate into cells of the three germ layers. The pPSCs transfected with fuw-DsRed (pPSC-FDs) could be passaged with a stable expression of both DsRed and pluripotent markers. Notably, when pPSC-FDs were used as donor cells for somatic nuclear transfer, 11.52% of the reconstructed embryos developed into blastocysts, which was not significantly different from that of the reconstructed embryos derived from porcine embryonic fibroblasts. When pPSC-FDs were injected into day 4.5 blastocysts, they became involved in the in vitro embryonic development and contributed to the viscera of foetuses at day 50 of pregnancy as well as the developed placenta after the chimeric blastocysts were transferred into recipients. These findings indicated that the pPSCs were porcine pluripotent cells; that this would be a useful cell line for porcine genetic engineering and a valuable cell line for clarifying the molecular mechanism of pluripotency regulation in pigs. PMID:26991423

  13. Adoptive immunotherapy for acute leukemia:New insights in chimeric antigen receptors

    Institute of Scientific and Technical Information of China (English)

    Ma?l; Heiblig; Mohamed; Elhamri; Mauricette; Michallet; Xavier; Thomas

    2015-01-01

    Relapses remain a major concern in acute leukemia. It is well known that leukemia stem cells(LSCs) hide in hematopoietic niches and escape to the immune system surveillance through the outgrowth of poorly immunogenic tumor-cell variants and the suppression of the active immune response. Despitethe introduction of new reagents and new therapeutic approaches, no treatment strategies have been able to definitively eradicate LSCs. However, recent adoptive immunotherapy in cancer is expected to revolutionize our way to fight against this disease, by redirecting the immune system in order to eliminate relapse issues. Initially described at the onset of the 90’s, chimeric antigen receptors(CARs) are recombinant receptors transferred in various T cell subsets, providing specific antigens binding in a non-major histocompatibility complex restricted manner, and effective on a large variety of human leukocyte antigen-divers cell populations. Once transferred, engineered T cells act like an expanding "living drug" specifically targeting the tumor-associated antigen, and ensure long-term antitumor memory. Over the last decades, substantial improvements have been made in CARs design. CAR T cells have finally reached the clinical practice and first clinical trials have shown promising results. In acute lymphoblastic leukemia, high rate of complete and prolonged clinical responses have been observed after anti-CD19 CAR T cell therapy, with specific but manageable adverse events. In this review, our goal was to describe CAR structures and functions, and to summarize recent data regarding pre-clinical studies and clinical trials in acute leukemia.

  14. Dual Regulation of a Chimeric Plant Serine/Threonine Kinase by Calcium and Calcium/Calmodulin

    Science.gov (United States)

    Takezawa, D.; Ramachandiran, S.; Paranjape, V.; Poovaiah, B. W.

    1996-01-01

    A chimeric Ca(2+)/calmodulin-dependent protein kinase (CCaMK) gene characterized by a catalytic domain, a calmodulin-binding domain, and a neural visinin-like Ca(2+)-binding domain was recently cloned from plants. The Escherichia coli-expressed CCaMK phosphorylates various protein and peptide substrates in a Ca(2+)/calmodulin-dependent manner. The calmodulin-binding region of CCAMK has similarity to the calmodulin-binding region of the alpha-subunit of multifunctional Ca(2+)/calmodulin-dependent protein kinase (CaMKII). CCaMK exhibits basal autophosphorylation at the threonine residue(s) (0.098 mol of P-32/mol) that is stimulated 3.4-fold by Ca(2+) (0.339 mol of P-32/mol), while calmodulin inhibits Ca(2+)-stimulated autophosphorylation to the basal level. A deletion mutant lacking the visinin-like domain did not show Ca(2+)-simulated autophosphorylation activity but retained Ca(2+)/calmodulin-dependent protein kinase activity at a reduced level. Ca(2+)-dependent mobility shift assays using E.coli-expressed protein from residues 358-520 revealed that Ca(2+) binds to the visinin-like domain. Studies with site-directed mutants of the visinin-like domain indicated that EF-hands II and III are crucial for Ca(2+)-induced conformational changes in the visinin-like domain. Autophosphorylation of CCaMK increases Ca(2+)/calmodulin-dependent protein kinase activity by about 5-fold, whereas it did not affect its C(2+)-independent activity. This report provides evidence for the existence of a protein kinase in plants that is modulated by Ca(2+) and Ca(2+)/calmodulin. The presence of a visinin-like Ca(2+)-binding domain in CCaMK adds an additional Ca(2+)-sensing mechanism not previously known to exist in the Ca(2+)/calmodulin-mediated signaling cascade in plants.

  15. Preubiquitinated chimeric ErbB2 is constitutively endocytosed and subsequently degraded in lysosomes

    Energy Technology Data Exchange (ETDEWEB)

    Vuong, Tram Thu [Institute of Clinical Medicine, University of Oslo, Rikshospitalet, 0027 Oslo (Norway); Berger, Christian [Department of Pathology, Oslo University Hospital, Rikshospitalet, P.O. Box 4950 Nydalen, 0424 Oslo (Norway); Bertelsen, Vibeke; Rødland, Marianne Skeie [Institute of Clinical Medicine, University of Oslo, Rikshospitalet, 0027 Oslo (Norway); Stang, Espen [Department of Pathology, Oslo University Hospital, Rikshospitalet, P.O. Box 4950 Nydalen, 0424 Oslo (Norway); Madshus, Inger Helene, E-mail: i.h.madshus@medisin.uio.no [Institute of Clinical Medicine, University of Oslo, Rikshospitalet, 0027 Oslo (Norway); Department of Pathology, Oslo University Hospital, Rikshospitalet, P.O. Box 4950 Nydalen, 0424 Oslo (Norway)

    2013-02-01

    The oncoprotein ErbB2 is endocytosis-deficient, probably due to its interaction with Heat shock protein 90. We previously demonstrated that clathrin-dependent endocytosis of ErbB2 is induced upon incubation of cells with Ansamycin derivatives, such as geldanamycin and its derivative 17-AAG. Furthermore, we have previously demonstrated that a preubiquitinated chimeric EGFR (EGFR-Ub{sub 4}) is constitutively endocytosed in a clathrin-dependent manner. We now demonstrate that also an ErbB2-Ub{sub 4} chimera is endocytosed constitutively and clathrin-dependently. Upon expression, the ErbB2-Ub{sub 4} was further ubiquitinated, and by Western blotting, we demonstrated the formation of both Lys48-linked and Lys63-linked polyubiquitin chains. ErbB2-Ub{sub 4} was constitutively internalized and eventually sorted to late endosomes and lysosomes where the fusion protein was degraded. ErbB2-Ub{sub 4} was not cleaved prior to internalization. Interestingly, over-expression of Ubiquitin Interaction Motif-containing dominant negative fragments of the clathrin adaptor proteins epsin1 and Eps15 negatively affected endocytosis of ErbB2. Altogether, this argues that ubiquitination is sufficient to induce clathrin-mediated endocytosis and lysosomal degradation of the otherwise plasma membrane localized ErbB2. Also, it appears that C-terminal cleavage is not required for endocytosis. -- Highlights: ► A chimera containing ErbB2 and a tetra-Ubiquitin chain internalizes constitutively. ► Receptor fragmentation is not required for endocytosis of ErbB2. ► Ubiquitination is sufficient to induce endocytosis and degradation of ErbB2. ► ErbB2-Ub4 is internalized clathrin-dependently.

  16. Sex steroids level in blood plasma and ovarian follicles of the chimeric chicken.

    Science.gov (United States)

    Sechman, A; Lakota, P; Wojtysiak, D; Hrabia, A; Mika, M; Lisowski, M; Czekalski, P; Rzasa, J; Kapkowska, E; Bednarczyk, M

    2006-12-01

    The study was performed to determine the hormonal status of mature germline chimeras obtained by blastodermal cell transfer from chicken embryos of a donor breed [Green-legged Partridgelike breed (GP) x Araucana (AR)] to those of a recipient breed [White Leghorn (WL)] being at the same stage of embryonic development. The egg-laying chimeras and WL hens (control) of the same age were used in the experiment. At first, blood samples were taken from each bird at 0.5, 5, 12.5 and 18.5 h following oviposition. Subsequently, the chimeras and the WL hens were decapitated 1-2 h after ovulation. A stroma and the following follicles were isolated from the ovary: white normal (1-4, 4-6 and 6-8 mm), white atretic and yellow preovulatory follicles (F4-F1). Sex hormones, progesterone (P4), testosterone (T) and oestradiol (E2) in blood plasma and ovarian follicles were determined radioimmunologically. The activity of the 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the granulosa and theca layers of the follicles was analysed histochemically. In chimeric chickens, a higher level of T in blood plasma during the ovulatory cycle was noticed. However, in the stroma, white prehierarchical and medium-size preovulatory ovarian follicles the level of T was significantly lower. With respect to E2, its elevated levels were found both in blood and in the ovarian follicles. There were no significant differences in P4 concentrations in blood plasma while in ovarian follicles a higher level was observed only in white 6-8 mm follicles. 3beta-HSD activity in granulosa and theca layers of the ovarian follicles in chimeras was not different from that in the WL hens. In conclusion, the results obtained indicate that germline chimeras exhibit significant alterations in sex hormone levels in the ovary and blood plasma, which in turn may affect their reproductive abilities. PMID:17105570

  17. Focused Directed Evolution of Aryl-Alcohol Oxidase in Saccharomyces cerevisiae by Using Chimeric Signal Peptides.

    Science.gov (United States)

    Viña-Gonzalez, Javier; Gonzalez-Perez, David; Ferreira, Patricia; Martinez, Angel T; Alcalde, Miguel

    2015-09-01

    Aryl-alcohol oxidase (AAO) is an extracellular flavoprotein that supplies ligninolytic peroxidases with H2O2 during natural wood decay. With a broad substrate specificity and highly stereoselective reaction mechanism, AAO is an attractive candidate for studies into organic synthesis and synthetic biology, and yet the lack of suitable heterologous expression systems has precluded its engineering by directed evolution. In this study, the native signal sequence of AAO from Pleurotus eryngii was replaced by those of the mating α-factor and the K1 killer toxin, as well as different chimeras of both prepro-leaders in order to drive secretion in Saccharomyces cerevisiae. The secretion of these AAO constructs increased in the following order: preproα-AAO > preαproK-AAO > preKproα-AAO > preproK-AAO. The chimeric preαproK-AAO was subjected to focused-directed evolution with the aid of a dual screening assay based on the Fenton reaction. Random mutagenesis and DNA recombination was concentrated on two protein segments (Met[α1]-Val109 and Phe392-Gln566), and an array of improved variants was identified, among which the FX7 mutant (harboring the H91N mutation) showed a dramatic 96-fold improvement in total activity with secretion levels of 2 mg/liter. Analysis of the N-terminal sequence of the FX7 variant confirmed the correct processing of the preαproK hybrid peptide by the KEX2 protease. FX7 showed higher stability in terms of pH and temperature, whereas the pH activity profiles and the kinetic parameters were maintained. The Asn91 lies in the flavin attachment loop motif, and it is a highly conserved residue in all members of the GMC superfamily, except for P. eryngii and P. pulmonarius AAO. The in vitro involution of the enzyme by restoring the consensus ancestor Asn91 promoted AAO expression and stability. PMID:26162870

  18. In vivo anti-tumor activity of marine hematopoietic stem cells expressing a p185HER2-specific chimeric T-cell receptor gene

    Institute of Scientific and Technical Information of China (English)

    JIAN MIN YANG; MICHAEL S FRIEDMAN; MARIANNE T HUBEN; JENNIFER FULLER; QIAO LI; ALFRED E CHANG; JAMES J MULE; KEVIN T MCDONAGH

    2006-01-01

    We have confirmed efficient anti-tumor activities of the peripheral lymphocytes transduced with a p185HER2-specific chimeric T-cell receptor gene both in murine and in human in our previous studies. To further test the feasibility of chimeric T-cell receptor in a bone marrow transplantation model, we first, made two murine tumor cell lines: MT901 and MCA-205, to express human p185HER2by retroviral gene transduction. Murine bone marrow cells were retrovirally transduced to express the chimeric T-cell receptor and gene-modified bone marrow cells were transplanted into lethally irradiated mouse. Six months post transplantation, p185HER2-positive tumor cells: MT-901/HER2 or MCA-205/HER2 was subcutaneously or intravenously injected to make mouse models simulating primary breast cancer or pulmonary metastasis. The in vivo anti-tumor effects were monitored by the size of the subcutaneous tumor or counting the tumor nodules in the lungs after India ink staining. The size of the subcutaneous tumor was significantly inhibited and the number of pulmonary nodules were significantly decreased in mouse recipients transplanted with chimeric T-cell receptor modified bone marrow cells compared with the control group. Our results suggest the efficient in vivo anti-tumor activities of chimeric T-cell receptor gene modified bone marrow cells.

  19. PU.1-Silenced Dendritic Cells Induce Mixed Chimerism and Alleviate Intestinal Transplant Rejection in Rats via a Th1 to Th2 Shift

    Directory of Open Access Journals (Sweden)

    Xingwei Xu

    2016-01-01

    Full Text Available Background/Aims: Intestinal transplantation is an effective treatment for end-stage bowel failure; however, graft rejection and the toxicity associated with non-specific immunosuppression are major limitations of this procedure. Studies have shown that mixed chimerism can produce post-transplantation immune tolerance. Here, we demonstrate that in rat intestinal transplantation, PU.1-silenced dendritic cells (DCs plus bone marrow (BM cell transfusion results in mixed chimerism, and we investigate the mechanisms responsible for the effects of mixed chimerism rejection. Methods: In a model of intestinal transplantation, male Brown Norway rats were the donors, and female Lewis rats were the recipients that were randomly divided into 4 groups: control, BM, BM-imDCs and BM-PU.1. The dynamic changes in graft morphology, rejection scoring and serum concentrations of Th1/Th2-related cytokines were investigated on postoperative days 0, 7, 14, 21, and 30. Results: The BM-PU.1 group had better graft health, milder pathologic injuries, and lower rejection grades compared with the other groups. The rates of mixed chimerism were significantly highest in the BM-PU.1 group and correlated with decreases in serum IL-2 and increases in serum IL-10. Conclusion: Transfusion of PU.1-silenced DCs and BM cells induces stable mixed chimerism and has the potential to reduce pathologic injuries via a pro-Th2 shift in the Th1/Th2 balance.

  20. Chimerism Analysis of Cell-Free DNA in Patients Treated with Hematopoietic Stem Cell Transplantation May Predict Early Relapse in Patients with Hematologic Malignancies

    Directory of Open Access Journals (Sweden)

    Mahmoud Aljurf

    2016-01-01

    Full Text Available Background. We studied DNA chimerism in cell-free DNA (cfDNA in patients treated with HSCT. Methods. Chimerism analysis was performed on CD3+ cells, polymorphonuclear (PMN cells, and cfDNA using 16 small tandem repeat loci. The resulting labeled PCR-products were size-fractionated and quantified. Results. Analyzing samples from 191 patients treated with HSCT for nonneoplastic hematologic disorders demonstrated that the cfDNA chimerism is comparable to that seen in PMN cells. Analyzing leukemia patients (N = 126 showed that, of 84 patients with 100% donor DNA in PMN, 16 (19% had evidence of clinical relapse and >10% recipient DNA in the plasma. Additional 16 patients of the 84 (19% showed >10% recipient DNA in plasma, but without evidence of relapse. Eight patients had mixed chimerism in granulocytes, lymphocytes, and plasma, but three of these patients had >10% recipient DNA in plasma compared to PMN cells and these three patients had clinical evidence of relapse. The remaining 34 patients showed 100% donor DNA in both PMN and lymphocytes, but cfDNA showed various levels of chimerism. Of these patients 14 (41% showed laboratory or clinical evidence of relapse and all had >10% recipient DNA in cfDNA. Conclusion. Monitoring patients after HSCT using cfDNA might be more reliable than cellular DNA in predicting early relapse.

  1. Chimerism Analysis of Cell-Free DNA in Patients Treated with Hematopoietic Stem Cell Transplantation May Predict Early Relapse in Patients with Hematologic Malignancies

    Science.gov (United States)

    Aljurf, Mahmoud; Abalkhail, Hala; Alseraihy, Amal; Mohamed, Said Y.; Ayas, Mouhab; Alsharif, Fahad; Alzahrani, Hazza; Al-Jefri, Abdullah; Aldawsari, Ghuzayel; Al-Ahmari, Ali; Belgaumi, Asim F.; Walter, Claudia Ulrike; El-Solh, Hassan; Rasheed, Walid; Albitar, Maher

    2016-01-01

    Background. We studied DNA chimerism in cell-free DNA (cfDNA) in patients treated with HSCT. Methods. Chimerism analysis was performed on CD3+ cells, polymorphonuclear (PMN) cells, and cfDNA using 16 small tandem repeat loci. The resulting labeled PCR-products were size-fractionated and quantified. Results. Analyzing samples from 191 patients treated with HSCT for nonneoplastic hematologic disorders demonstrated that the cfDNA chimerism is comparable to that seen in PMN cells. Analyzing leukemia patients (N = 126) showed that, of 84 patients with 100% donor DNA in PMN, 16 (19%) had evidence of clinical relapse and >10% recipient DNA in the plasma. Additional 16 patients of the 84 (19%) showed >10% recipient DNA in plasma, but without evidence of relapse. Eight patients had mixed chimerism in granulocytes, lymphocytes, and plasma, but three of these patients had >10% recipient DNA in plasma compared to PMN cells and these three patients had clinical evidence of relapse. The remaining 34 patients showed 100% donor DNA in both PMN and lymphocytes, but cfDNA showed various levels of chimerism. Of these patients 14 (41%) showed laboratory or clinical evidence of relapse and all had >10% recipient DNA in cfDNA. Conclusion. Monitoring patients after HSCT using cfDNA might be more reliable than cellular DNA in predicting early relapse. PMID:27006832

  2. Chimeric peptide containing both B and T cells epitope of tumor-associated antigen L6 enhances anti-tumor effects in HLA-A2 transgenic mice.

    Science.gov (United States)

    Lin, Su-I; Huang, Ming-Hsi; Chang, Yu-Wen; Chen, I-Hua; Roffler, Steve; Chen, Bing-Mae; Sher, Yuh-Pyng; Liu, Shih-Jen

    2016-07-28

    Synthetic peptides are attractive for cancer immunotherapy because of their safety and flexibility. In this report, we identified a new B cell epitope of tumor-associated antigen L6 (TAL6) that could induce antibody-dependent cellular cytotoxicity (ADCC) in vivo. We incorporated the B cell epitope with a cytotoxic T lymphocyte (CTL) and a helper T (Th) epitope to form a chimeric long peptide. We formulated the chimeric peptide with different adjuvants to immunize HLA-A2 transgenic mice and evaluate their immunogenicity. The chimeric peptide formulated with an emulsion type nanoparticle (PELC) adjuvant and a toll-like receptor 9 agonist (CpG ODN) (PELC/CpG) induced the greatest ADCC and CTL responses. The induced anti-tumor immunity inhibited the growth of TAL6-positive cancer cells. Moreover, we observed that immunization with the chimeric peptide inhibited cancer cell migration in vitro and metastasis in vivo. These data suggest that a chimeric peptide containing both B and T cell epitopes of TAL6 formulated with PELC/CpG adjuvant is feasible for cancer immunotherapy. PMID:27130449

  3. Uncertainty characterization and quantification in air pollution models. Application to the CHIMERE model

    Science.gov (United States)

    Debry, Edouard; Mallet, Vivien; Garaud, Damien; Malherbe, Laure; Bessagnet, Bertrand; Rouïl, Laurence

    2010-05-01

    Prev'Air is the French operational system for air pollution forecasting. It is developed and maintained by INERIS with financial support from the French Ministry for Environment. On a daily basis it delivers forecasts up to three days ahead for ozone, nitrogene dioxide and particles over France and Europe. Maps of concentration peaks and daily averages are freely available to the general public. More accurate data can be provided to customers and modelers. Prev'Air forecasts are based on the Chemical Transport Model CHIMERE. French authorities rely more and more on this platform to alert the general public in case of high pollution events and to assess the efficiency of regulation measures when such events occur. For example the road speed limit may be reduced in given areas when the ozone level exceeds one regulatory threshold. These operational applications require INERIS to assess the quality of its forecasts and to sensitize end users about the confidence level. Indeed concentrations always remain an approximation of the true concentrations because of the high uncertainty on input data, such as meteorological fields and emissions, because of incomplete or inaccurate representation of physical processes, and because of efficiencies in numerical integration [1]. We would like to present in this communication the uncertainty analysis of the CHIMERE model led in the framework of an INERIS research project aiming, on the one hand, to assess the uncertainty of several deterministic models and, on the other hand, to propose relevant indicators describing air quality forecast and their uncertainty. There exist several methods to assess the uncertainty of one model. Under given assumptions the model may be differentiated into an adjoint model which directly provides the concentrations sensitivity to given parameters. But so far Monte Carlo methods seem to be the most widely and oftenly used [2,3] as they are relatively easy to implement. In this framework one

  4. Proline-rich tandem repeats of antibody complementarity-determining regions bind and neutralize human immunodeficiency virus type 1 particles.

    OpenAIRE

    Fontenot, J D; Zacharopoulos, V R; Phillips, D M

    1996-01-01

    The proline-rich tandem repeat domain of human mucin MUC1 forms an extended structure containing large repeating loops that are crested by a turn. We show that the repeating-loop structure of MUC1 can be replaced by an antibody complementarity-determining region loop of a human immunodeficiency virus type 1 (HIV-1)-specific neutralizing antibody to create a chimeric, multivalent, mucin-like, anti-HIV-1 compound. We used 8 residues of an antibody molecule to replace 8 of 20 residues of the MUC...

  5. Monoclonal antibody therapy for Junin virus infection.

    Science.gov (United States)

    Zeitlin, Larry; Geisbert, Joan B; Deer, Daniel J; Fenton, Karla A; Bohorov, Ognian; Bohorova, Natasha; Goodman, Charles; Kim, Do; Hiatt, Andrew; Pauly, Michael H; Velasco, Jesus; Whaley, Kevin J; Altmann, Friedrich; Gruber, Clemens; Steinkellner, Herta; Honko, Anna N; Kuehne, Ana I; Aman, M Javad; Sahandi, Sara; Enterlein, Sven; Zhan, Xiaoguo; Enria, Delia; Geisbert, Thomas W

    2016-04-19

    Countermeasures against potential biothreat agents remain important to US Homeland Security, and many of these pharmaceuticals could have dual use in the improvement of global public health. Junin virus, the causative agent of Argentine hemorrhagic fever (AHF), is an arenavirus identified as a category A high-priority agent. There are no Food and Drug Administration (FDA) approved drugs available for preventing or treating AHF, and the current treatment option is limited to administration of immune plasma. Whereas immune plasma demonstrates the feasibility of passive immunotherapy, it is limited in quantity, variable in quality, and poses safety risks such as transmission of transfusion-borne diseases. In an effort to develop a monoclonal antibody (mAb)-based alternative to plasma, three previously described neutralizing murine mAbs were expressed as mouse-human chimeric antibodies and evaluated in the guinea pig model of AHF. These mAbs provided 100% protection against lethal challenge when administered 2 d after infection (dpi), and one of them (J199) was capable of providing 100% protection when treatment was initiated 6 dpi and 92% protection when initiated 7 dpi. The efficacy of J199 is superior to that previously described for all other evaluated drugs, and its high potency suggests that mAbs like J199 offer an economical alternative to immune plasma and an effective dual use (bioterrorism/public health) therapeutic. PMID:27044104

  6. A high-affinity CDR-grafted antibody against influenza A H5N1 viruses recognizes a conserved epitope of H5 hemagglutinin.

    Directory of Open Access Journals (Sweden)

    Feifei Xiong

    Full Text Available Highly pathogenic avian influenza (HPAI H5N1 virus infection is still a potential threat to public health worldwide. While vaccines and antiviral drugs are currently under development, neutralizing antibodies could offer an alternative strategy to prevent and treat H5N1 virus infection. In the present study, we had developed a humanized antibody against H5N1 viruses from mouse-derived hybridoma in order to minimize its immunogenicity for potential clinical application. The humanized antibody hH5M9 was generated by transferring the mouse complementarity determining region (CDR residues together with four key framework region (FR residues onto the FR of the human antibody. This humanized antibody exhibited high affinity and specificity comparable to the parental mouse or chimeric counterpart with broad and strong neutralization activity against all H5N1 clades and subclades except for Egypt clades investigated. Furthermore, through epitope mapping we identified a linear epitope on the top region of hemagglutinin (HA that was H5N1 specific and conserved. Our results for the first time reported a humanized antibody against H5N1 viruses by CDR grafting method. With the expected lower immunogenicity, this humanized antibody was expected to be more efficacious than murine or human-mouse chimeric antibodies for future application in humans.

  7. Comparison of satellite NO2 results with mobile MAX-DOAS observations and CHIMERE model simulations for Paris

    Science.gov (United States)

    Shaiganfar, Reza; Beirle, Steffen; Petetin, Herve; Zhang, Qiji; Beekmann, Matthias; Wagner, Thomas

    2013-04-01

    Megacities are localized, heterogeneous and variable sources of various air pollutants, having great impact on air quality and ultimately on climate. Within the European project MEGAPOLI we characterise and quantify the pollution levels and emissions using spectroscopic observations from satellite and ground based instruments mounted on a car. The mobile observations are conducted on circles with different radii around megacities. From the satellite observations the link from local to regional and global scales can be made. Especially the impact of important sources like megacities on the surrounding areas and also over longer distances can be studied. The combination with the mobile measurements adds information about the heterogeneity within a satellite pixel and the diurnal cycle, which are not well captured from satellite observations. The CHIMERE model is used to produce daily 3D fields of different trace gases, ozone and aerosols. We compare the CHIMERE model with mobile MAX-DOAS and OMI satellite observations. The mobile measurements are also used for validation of the satellite observations. We compare the tropospheric NO2 from OMI (TEMIS) with our mobile MAX-DOAS vertical column densities (VCDs). In general good agreement of the spatial patterns was found between differet data sets. However, the mobile MAX-DOAS measurements usually showed much finer details of the horizontal distributions than the satellite and model data. Also differences in the absolute values were found: The Chimere data are17x% lower and 45% lower than the mobile MAX-DOAS data in summer and winter, respectively. The satellite data are about 50 % lower than mobile MAX-DOAS.

  8. Advances on the treatment of solid tumor by 131I labeled mouse-human chimeric tumor necrosis therapy monoclonal antibody

    International Nuclear Information System (INIS)

    131I labeled mouse-human chimeric tumor necrosis therapy monoclonal antibody (131I-chTNT) is a kind of new drug targeting at degenerated or necrotic nuclei in the tumor necrosis zone,and may be applicable to the majority of human solid tumors, such as lung cancer, liver cancer,colon carcinoma and glioma, while conventional tumor cell monoclonal antibody can target only tumor cell surface antigen. Enhanced effects can be achieved by 131I-chTNT in combination with other therapies, such as radiotherapy,chemotherapy or radiofrequency ablation, which may increase tumor necrosis region and expose more combinative targets. (authors)

  9. Abbreviated incubation times for human prions in mice expressing a chimeric mouse–human prion protein transgene

    OpenAIRE

    Korth, Carsten; Kaneko, Kiyotoshi; Groth, Darlene; Heye, Norbert; Telling, Glenn; Mastrianni, James; Parchi, Piero; Gambetti, Pierluigi; Will, Robert; Ironside, James; Heinrich, Cornelia; Tremblay, Patrick; Stephen J DeArmond; Prusiner, Stanley B.

    2003-01-01

    Transgenic (Tg) mouse lines that express chimeric mouse–human prion protein (PrP), designated MHu2M, are susceptible to prions from patients with sporadic Creutzfeldt–Jakob disease (sCJD). With the aim of decreasing the incubation time to fewer than 200 days, we constructed transgenes in which one or more of the nine human residues in MHu2M were changed to mouse. The construct with murine residues at positions 165 and 167 was expressed in Tg(MHu2M,M165V,E167Q) mice and resulted in shortening ...

  10. Genetically engineered T cells bearing chimeric nanoconstructed receptors harboring TAG-72-specific camelid single domain antibodies as targeting agents

    DEFF Research Database (Denmark)

    Sharifzadeh, Zahra; Rahbarizadeh, Fatemeh; Shokrgozar, Mohammad A;

    2013-01-01

    Despite the preclinical success of adoptive therapy with T cells bearing chimeric nanoconstructed antigen receptors (CARs), certain limitations of this therapeutic approach such as the immunogenicity of the antigen binding domain, the emergence of tumor cell escape variants and the blocking...... expressing tumor cells, the combination of CD3ζ, OX40, CD28 as well as the CH3-CH2-hinge-hinge domains most efficiently triggered T cell activation. Importantly, CAR mediated functions were not blocked by the soluble TAG-72 antigen at a supraphysiological concentration. Our approach may have the potential to...

  11. Chimeric antibody with human constant regions and mouse variable regions directed against carcinoma-associated antigen 17-1A

    International Nuclear Information System (INIS)

    The authors have cloned the genomic DNA fragments encoding the heavy and light chain variable regions of monoclonal antibody 17-1A, and they have inserted them into mammalian expression vectors containing genomic DNA segments encoding human γ3 and kappa constant regions. The transfer of these expression vectors containing mouse-human chimeric immunoglobulin genes into Sp2/0 mouse myeloma cells resulted in the production of functional IgG that retained the specific binding to the surface antigen 17-1A expressed on colorectal carcinoma cells

  12. A Molecular Model for Cocaine Binding by the Immunotherapeutic Human/Mouse Chimeric Monoclonal Antibody 2E2

    OpenAIRE

    Lape, Michael; Paula, Stefan; Ball, William J.

    2010-01-01

    Immunotherapy by cocaine-binding monoclonal antibodies (mAbs) has emerged as a promising strategy for the treatment of cocaine addiction. The human (γ1 heavy chain)/murine (λ light chain) chimeric mAb 2E2 has excellent affinity and specificity for cocaine and recent animal studies have demonstrated 2E2’s ability in vivo to reduce cocaine levels in the brain as well as alter cocaine self-administration behavior in rats. In this study, we used mAb 2E2 amino acid sequence information to create a...

  13. Construction and analysis of variants of a polyvalent Lyme disease vaccine: approaches for improving the immune response to chimeric vaccinogens

    OpenAIRE

    Earnhart, Christopher G.; Marconi, Richard T.

    2007-01-01

    There is currently no Lyme disease vaccine commercially available for use in humans. Outer surface protein C (OspC) of the Borrelia has been widely investigated as a potential vaccinogen. At least 38 OspC types have been defined. While the antibody response to OspC is protective, the range of protection is narrow due to the localization of protective epitopes within OspC type-specific domains. To develop a broadly protective vaccine, we previously constructed a tetravalent chimeric vaccinogen...

  14. Paranoid males have reduced lateralisation for processing of negative emotions: an investigation using the chimeric faces test.

    Science.gov (United States)

    Bourne, Victoria J; McKay, Ryan T

    2014-01-01

    Reduced strength of lateralisation in patients with schizophrenia has been reported in a number of studies. However the exact nature of this relationship remains unclear. In this study, lateralisation for processing emotional faces was measured using the chimeric faces test and examined in relation to paranoia in a non-clinical sample. For males only, those with higher scores on a paranoia questionnaire had reduced lateralisation for processing negative facial emotion. For females there were no significant relationships. These findings suggest that atypical patterns of lateralisation for processing emotional stimuli may be implicated in, or associated with, increased levels of paranoia. PMID:23844655

  15. Nonirradiated NOD/SCID-Human Chimeric Animal Model for Primary Human Multiple Myeloma : A Potential in Vivo Culture System

    OpenAIRE

    Huang, Shang-Yi; Tien, Hwei-Fang; Su, Fang-Hsein; Hsu, Su-Ming

    2004-01-01

    The NOD/SCID human chimeric animal model was generated by implanting of human fetal bones (FBs) into subcutaneous sites of NOD/SCID mice (NOD/SCID-hu+), followed by inoculation of primary bone marrow mononuclear cells (BMNCs) obtained from patients with multiple myeloma (MM) into the FBs. The BMNCs from 30 patients with MM were inoculated, and 28 (93%) of them revealed evidence of tumor growth of myeloma cells (MCs) in the NOD/SCID-hu+ mice. Intriguingly, 17 (61%) of the 28 patients’ BMNCs in...

  16. Functional analysis of chimeric genes obtained by exchanging homologous domains of the mouse mdr1 and mdr2 genes.

    OpenAIRE

    Buschman, E; Gros, P.

    1991-01-01

    A full-length cDNA clone for the mouse mdr1 gene can confer multidrug resistance when introduced by transfection into otherwise drug-sensitive cells. In the same assay, a full-length cDNA clone for a closely related member of the mouse mdr gene family, mdr2, fails to confer multidrug resistance. To identify the domains of mdr1 which are essential for multidrug resistance and which may be functionally distinct in mdr2, we have constructed chimeric cDNA molecules in which discrete domains of md...

  17. Chimeric TLS/FUS-CHOP Gene Expression and the Heterogeneity of its Junction in Human Myxoid and Round Cell Liposarcoma

    OpenAIRE

    Kuroda, Masahiko; Ishida, Tsuyoshi; Horiuchi, Hajime; Kida, Naotoshi; Uozaki, Hiroshi; TAKEUCHI, Hajime; Tsuji, Kaori; Imamura, Tetsuo; Mori, Shigeo; Machinami, Rikuo; Watanabe, Toshiki

    1995-01-01

    Myxoid liposarcomas have a unique and specific t(12;16)(q13;p11) chromosomal translocation. The breakpoint has recently been identified and shown to involve the TLS/FUS gene on chromosome 16 and the CHOP gene on chromosome 12. This translocation causes fusion of these genes resulting in the expression of a novel chimeric TLS/FUS-CHOP message. Using the polymerase chain reaction with primer sets derived from sequences of TLS/FUS and CHOP cDNAs, we could amplify three types of the fusion transc...

  18. Voltage-Jump Relaxation Kinetics for Wild-type and Chimeric β Subunits of Neuronal Nicotinic Receptors

    OpenAIRE

    Figl, Antonio; Labarca, Cesar; Davidson, Norman; Lester, Henry A.; Cohen, Bruce N.

    1996-01-01

    We have studied the voltage-jump relaxation currents for a series of neuronal nicotinic acetylcholine receptors resulting from the coexpression of wild-type and chimeric β4/β2 subunits with α3 subunits in Xenopus oocytes. With acetylcholine as the agonist, the wild-type α3β4 receptors displayed five- to eightfold slower voltage-jump relaxations than did the wild-type α3β2 receptors. In both cases, the relaxations could best be described by two exponential components of approximately equal amp...

  19. Viruses Infecting Reptiles

    Directory of Open Access Journals (Sweden)

    Rachel E. Marschang

    2011-11-01

    Full Text Available A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch’s postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions.

  20. Chimeric Mice with Competent Hematopoietic Immunity Reproduce Key Features of Severe Lassa Fever

    OpenAIRE

    Lisa Oestereich; Anja Lüdtke; Paula Ruibal; Elisa Pallasch; Romy Kerber; Toni Rieger; Stephanie Wurr; Sabrina Bockholt; Pérez-Girón, José V; Susanne Krasemann; Stephan Günther; César Muñoz-Fontela

    2016-01-01

    Lassa fever (LASF) is a highly severe viral syndrome endemic to West African countries. Despite the annual high morbidity and mortality caused by LASF, very little is known about the pathophysiology of the disease. Basic research on LASF has been precluded due to the lack of relevant small animal models that reproduce the human disease. Immunocompetent laboratory mice are resistant to infection with Lassa virus (LASV) and, to date, only immunodeficient mice, or mice expressing human HLA, have...

  1. HLA-DR4-IE chimeric class II transgenic, murine class II-deficient mice are susceptible to experimental allergic encephalomyelitis

    OpenAIRE

    1996-01-01

    To investigate the development of HLA-DR-associated autoimmune diseases, we generated transgenic (Tg) mice with HLA-DRA-IE alpha and HLA-DRB1*0401-IE beta chimeric genes. The transgene-encoded proteins consisted of antigen-binding domains from HLA-DRA and HLA-DRB1*0401 molecules and the remaining domains from the IE(d)-alpha and IE(d)-beta chains. The chimeric molecules showed the same antigen-binding specificity as HLA-DRB1*0401 molecules, and were functional in presenting antigens to T cell...

  2. Comparison of a chimeric anti-carcinoembryonic antigen antibody conjugated with visible or near-infrared fluorescent dyes for imaging pancreatic cancer in orthotopic nude mouse models

    OpenAIRE

    Maawy, Ali A.; Hiroshima, Yukihiko; Kaushal, Sharmeela; Luiken, George A.; Robert M Hoffman; Bouvet, Michael

    2013-01-01

    Abstract. The aim of this study was to evaluate a set of visible and near-infrared dyes conjugated to a tumor-specific chimeric antibody for high-resolution tumor imaging in orthotopic models of pancreatic cancer. BxPC-3 human pancreatic cancer was orthotopically implanted into pancreata of nude mice. Mice received a single intravenous injection of a chimeric anti-carcinoembryonic antigen antibody conjugated to one of the following fluorophores: 488-nm group (Alexa Fluor 488 or DyLight 488); ...

  3. Redirecting Therapeutic T Cells against Myelin-Specific T Lymphocytes Using a Humanized Myelin Basic Protein-HLA-DR2-{zeta} Chimeric Receptor

    DEFF Research Database (Denmark)

    Moisini, Ioana; Nguyen, Phuong; Fugger, Lars;

    2008-01-01

    Therapies that Ag-specifically target pathologic T lymphocytes responsible for multiple sclerosis (MS) and other autoimmune diseases would be expected to have improved therapeutic indices compared with Ag-nonspecific therapies. We have developed a cellular immunotherapy that uses chimeric receptors...... humanized mouse model system. Finally, the chimeric receptor-modified CTL ameliorated or blocked experimental allergic encephalomyelitis (EAE) disease mediated by MBP(84-102)/DR2-specific T lymphocytes. These results provide support for the further development of redirected therapeutic T cells able to...

  4. Immunogenicity of a chimeric peptide corresponding to T helper and B cell epitopes of the Chlamydia trachomatis major outer membrane protein

    OpenAIRE

    1992-01-01

    The immunogenicity of a chimeric T/B cell peptide corresponding to antigenically characterized epitopes of the Chlamydia trachomatis major outer membrane protein (MOMP) was studied in mice to further define its potential use in the development of a subunit vaccine in preventing blinding trachoma in humans. The chimeric peptide, designated A8-VDI, corresponds to a conserved MOMP T helper (Th) cell epitope(s) (A8, residues 106-130) and serovar A VDI (residues 66-80), which contains the serovar-...

  5. Testing for Human Immunodeficiency Virus

    Science.gov (United States)

    ... education Fact Sheet PFS005: Testing for Human Immunodeficiency Virus AUGUST 2015 • Reasons for Getting Tested • Who Should ... For More Information • Glossary Testing for Human Immunodeficiency Virus Human immunodeficiency virus (HIV) is the virus that ...

  6. Biochemical characterization and evaluation of cytotoxicity of antistaphylococcal chimeric protein P128

    Directory of Open Access Journals (Sweden)

    George Shilpa E

    2012-06-01

    Full Text Available Abstract Background Antibiotic resistant S. aureus infection is a global threat. Newer approaches are required to control this organism in the current scenario. Cell wall degrading enzymes have been proposed as antibacterial agents for human therapy. P128 is a novel antistaphylococcal chimeric protein under development against S. aureus for human use which derives its bacterial cell wall degrading catalytic endopeptidase domain from ORF56, the Phage K tail-structure associated enzyme. Lead therapeutic entities have to be extensively characterized before they are assessed in animals for preclinical safety and toxicity. P128 is effective against antibiotic resistant strains as well as against a panel of isolates of global significance. Its efficacy against S. aureus in vivo has been established in our lab. Against this background, this study describes the characterization of this protein for its biochemical properties and other attributes. Results We evaluated the requirement or effect of divalent cations and the metal ion chelator, EDTA upon biological activity of P128. As the protein is intended for therapeutic use, we tested its activity in presence of body fluids and antibodies specific to P128. For the same reason, we used standard human cell lines to evaluate cytotoxic effects, if any. The divalent cations, calcium and magnesium at upto 25 mM and Zinc upto 2.5 mM neither inhibited nor enhanced P128 activity. Incubation of this protein with EDTA, human serum, plasma and blood also did not alter the antibacterial properties of the molecule. No inhibitory effect was observed in presence of hyper-immune sera raised against the protein. Finally, P128 did not show any cytotoxic effect on HEp2 and Vero cells at the highest concentration (5 mg/mL tested. Conclusions The results presented here throw light on several properties of protein P128. Taken together, these substantiate the potential of P128 for therapeutic use against S. aureus

  7. Analysis of Virus Algorithms

    Directory of Open Access Journals (Sweden)

    Jyoti Kalyani

    2006-01-01

    Full Text Available Security of wired and wireless networks is the most challengeable in today's computer world. The aim of this study was to give brief introduction about viruses and worms, their creators and characteristics of algorithms used by viruses. Here wired and wireless network viruses are elaborated. Also viruses are compared with human immune system. On the basis of this comparison four guidelines are given to detect viruses so that more secure systems are made. While concluding this study it is found that the security is most challengeable, thus it is required to make more secure models which automatically detect viruses and prevent the system from its affect.

  8. {sup 99m}Tc-labeled chimeric anti-NCA 95 antigranulocyte monoclonal antibody for bone marrow imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sarwar, M.; Higuchi, Tetsuya; Tomiyoshi, Katsumi [Gunma Univ., Maebashi (Japan). School of Medicine] [and others

    1998-09-01

    Chimeric mouse-human antigranulocyte monoclonal antibody (ch MAb) against non-specific cross-reacting antigen (NCA-95) was labeled with {sup 99m}Tc (using a direct method) and {sup 125}I (using the chloramine T method), and its binding to human granulocytes and LS-180 colorectal carcinoma cells expressing carcinoembryonic antigen on their surfaces, cross-reactive with anti-NCA-95 chimeric monoclonal antibody, increased in proportion to the number of cells added and reached more than 80% and 90%, respectively. In biodistribution studies, {sup 99m}Tc and {sup 125}I-labeled ch anti-NCA-95 MAb revealed high tumor uptake, and the tumor-to-blood ratio was 2.9 after 24 hours. The tumor-to-normal-organ ratio was also more than 3.0 in all organs except for the tumor-to-kidney ratio. Scintigrams of athymic nude mice confirmed the results of biodistribution studies that showed higher radioactivity in tumor and kidney of the mice administered with {sup 99m}Tc-labeled ch MAb. A normal volunteer injected with {sup 99m}Tc-labeled ch anti-NCA-95 antigranulocyte MAb showed clear bone marrow images, and a patient with aplastic anemia revealed irregular uptake in his lumbar spine, suggesting its utility for bone marrow scintigraphy and for the detection of hematological disorders, infections, and bone metastasis. (author)

  9. Structural Characterization by NMR of a Double Phosphorylated Chimeric Peptide Vaccine for Treatment of Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Stefan Berger

    2013-04-01

    Full Text Available Rational design of peptide vaccines becomes important for the treatment of some diseases such as Alzheimer’s disease (AD and related disorders. In this study, as part of a larger effort to explore correlations of structure and activity, we attempt to characterize the doubly phosphorylated chimeric peptide vaccine targeting a hyperphosphorylated epitope of the Tau protein. The 28-mer linear chimeric peptide consists of the double phosphorylated B cell epitope Tau229-237[pThr231/pSer235] and the immunomodulatory T cell epitope Ag85B241-255 originating from the well-known antigen Ag85B of the Mycobacterium tuberculosis, linked by a four amino acid sequence -GPSL-. NMR chemical shift analysis of our construct demonstrated that the synthesized peptide is essentially unfolded with a tendency to form a β-turn due to the linker. In conclusion, the -GPSL- unit presumably connects the two parts of the vaccine without transferring any structural information from one part to the other. Therefore, the double phosphorylated epitope of the Tau peptide is flexible and accessible.

  10. The role of bone marrow-derived cells in bone fracture repair in a green fluorescent protein chimeric mouse model

    International Nuclear Information System (INIS)

    We investigated the role of bone marrow cells in bone fracture repair using green fluorescent protein (GFP) chimeric model mice. First, the chimeric model mice were created: bone marrow cells from GFP-transgenic C57BL/6 mice were injected into the tail veins of recipient wild-type C57BL/6 mice that had been irradiated with a lethal dose of 10 Gy from a cesium source. Next, bone fracture models were created from these mice: closed transverse fractures of the left femur were produced using a specially designed device. One, three, and five weeks later, fracture lesions were extirpated for histological and immunohistochemical analyses. In the specimens collected 3 and 5 weeks after operation, we confirmed calluses showing intramembranous ossification peripheral to the fracture site. The calluses consisted of GFP- and osteocalcin-positive cells at the same site, although the femur consisted of only osteocalcin-positive cells. We suggest that bone marrow cells migrated outside of the bone marrow and differentiated into osteoblasts to make up the calluses

  11. Construction and analysis of variants of a polyvalent Lyme disease vaccine: approaches for improving the immune response to chimeric vaccinogens.

    Science.gov (United States)

    Earnhart, Christopher G; Marconi, Richard T

    2007-04-30

    There is currently no Lyme disease vaccine commercially available for use in humans. Outer surface protein C (OspC) of the Borrelia has been widely investigated as a potential vaccinogen. At least 38 OspC types have been defined. While the antibody response to OspC is protective, the range of protection is narrow due to the localization of protective epitopes within OspC type-specific domains. To develop a broadly protective vaccine, we previously constructed a tetravalent chimeric vaccinogen containing epitopes from OspC types A, B, K, and D. While this construct elicited bactericidal antibody against strains bearing each of the four OspC types, its solubility was low, and decreasing IgG titer to epitopes near the C-terminus of the construct was observed. In this report, construct solubility and immunogenicity were increased by dialysis against an Arg/Glu buffer. We also demonstrate the immunogenicity of the construct in alum. To further optimize epitope-specific immune responses, several constructs were generated with differing epitope organization or with putative C-terminal protective motifs. Analyses of murine antibody titers and isotype profiles induced by these constructs revealed that while the C-terminal tags did not enhance antibody titer, specific epitope reorganization and reiteration did. These analyses provide important information that can be exploited in the development of chimeric vaccinogens in general. PMID:17239505

  12. Iron carrier proteins facilitate engraftment of allogeneic bone marrow and enduring hemopoietic chimerism in the lethally irradiated host

    International Nuclear Information System (INIS)

    Cell-free supernatants of rabbit bone marrow were fractionated, separated, and purified by Ultrogel and Superose chromatography. A single fraction promoted engraftment of allogeneic bone marrow and enduring hemopoietic chimerism across the H-2 barrier in lethally irradiated mice. This 'bio-active' fraction, analyzed by reducing SDS-PAGE electrophoresis, and transblotted on PVDF membrane, and purified by reverse-phase HPLC and SDS-PAGE electrophoresis yielded a main prealbumin band that when examined for primary structure by Edman degradation, proved to be rabbit transferrin. This was also attested by highly specific precipitation of the prealbumin band with polyclonal antibodies to rabbit transferrin. Iron-saturated human transferrin, lactotransferrin, and egg transferrin (conalbumin) were assayed in irradiated C57BL/6 mice infused with bone marrow from histoincompatible BALB/c donors. Mice treated with iron-loaded transferrins survive and develop enduring allogeneic chimerism with no discernible signs of graft-versus-host disease. Iron carrier proteins thus provide an unique means of achieving successful engraftment of allogeneic bone marrow in immunologically hostile murine H-2 combinations

  13. Exchanging murine and human immunoglobulin constant chains affects the kinetics and thermodynamics of antigen binding and chimeric antibody autoreactivity.

    Directory of Open Access Journals (Sweden)

    Marcela Torres

    Full Text Available Mouse-human chimeric antibodies composed of murine variable (V and human (C chains are useful therapeutic reagents. Consequently, we investigated whether heterologous C-regions from mice and humans affected specificity and affinity, and determined the contribution of C(H glycosylation to antigen binding. The interaction of a 12-mer peptide mimetic with monoclonal antibody (mAb 18B7 to Cryptococcus neoformans glucuronoxylomannan, and its chimeric (ch and deglycosylated forms were studied by surface plasmon resonance. The equilibrium and rate association constants for the chAb were higher than for mAb 18B7. V region affinity was not affected by C(H region glycosylation whereas heterologous C region of the same isotype altered the Ab binding affinity and the specificity for self-antigens. Structural models displayed local differences that implied changes on the connectivity of residues. These findings suggest that V region conformational changes can be dictated by the C(H domains through an allosteric effect involving networks of highly connected amino acids.

  14. Chimeric molecules facilitate the degradation of androgen receptors and repress the growth of LNCaP cells

    Institute of Scientific and Technical Information of China (English)

    Yue-Qing Tang; Bang-Min Han; Xin-Quan Yao; Yan Hong; Yan Wang; Fu-Jun Zhao; Sheng-Qiang Yu; Xiao-Wen Sun; Shu-Jie Xia

    2009-01-01

    Post-translational degradation of protein plays an important role in cell life.We employed chimeric molecules (dihydrotestosterone-based proteolysis-targeting chimeric molecule [DHT-PROTAC]) to facilitate androgen receptor (AR) degradation via the ubiquitin-proteasome pathway (UPP) and to investigate the role of AR in cell proliferation and viability in androgen-sensitive prostate cancer cells.Western blot analysis and immunohistochemistry were applied to analyse AR levels in LNCaP cells after DHT-PROTAC treatment.Cell counting and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) cell viability assay were used to evaluate cell proliferation and viability after AR elimination in both LNCaP and PC-3 cells.AR was tagged for elimination via the UPP by DHT-PROTAC,and this could be blocked by proteasome inhibitors.Degradation of AR depended on DHT-PROTAC concentration,and either DHT or an ALAPYIP-(arg)s peptide could compete with DHT-PROTAC.Inhibition of cell proliferation and decreased viability were observed in LNCaP cells,but not in PC-3 or 786-O cells after DHT-PROTAC treatment.These data indicate that AR elimination is facilitated via the UPP by DHT-PROTAC,and that the growth of LNCaP cells is repressed after AR degradation.

  15. Bioactivity assays and application of 125I labeled human mouse chimeric anti-CD22 monoclonal antibody SM03

    International Nuclear Information System (INIS)

    To investigate the bioactivity and application of 125I labeled human mouse chimeric monoclonal SM03, SM03 was labeled with 125I using Indogen method. The labeled mixture was purified by Sephacryl S-300 HR separation chromospectry. The purity and concentration of separated fractions were determined by HPLC and Protein Assay Kit, respectively. Competitive binding method and ELISA method were used for bioactivity assays. 125I-SM03 was applied to screen cell lines which express the most abundant CD22 antigen. The purity and recovery of 125I-SM03 were >99% and >47%, respectively. The bioactivity of 125I- SM03 and SM03 hasn't significant difference in statistics. Ramos cell line had the strongest special radioactivity when 125I-SM03 bound with in Raji, Daudi and Ramos cell lines. Indogen method is a good way to label Human mouse chimeric anti-CD22 monoclonal antibody SM03 and the label will not affect the activity of SM03. The 125I-SM03 not only can be used for detect agent, but also may be put into market for NHL therapy. (authors)

  16. Exploiting chimeric human antibodies to characterize a protective epitope of Neisseria adhesin A, one of the Bexsero vaccine components.

    Science.gov (United States)

    Bertoldi, Isabella; Faleri, Agnese; Galli, Barbara; Lo Surdo, Paola; Liguori, Alessia; Norais, Nathalie; Santini, Laura; Masignani, Vega; Pizza, Mariagrazia; Giuliani, Marzia Monica

    2016-01-01

    Neisseria adhesin A (NadA) is one of the antigens of Bexsero, the recently licensed multicomponent vaccine against serogroup B Neisseria meningitidis (MenB). NadA belongs to the class of oligomeric coiled-coil adhesins and is able to mediate adhesion and invasion of human epithelial cells. As a vaccine antigen, NadA has been shown to induce high levels of bactericidal antibodies; however, the domains important for protective response are still unknown. In order to further investigate its immunogenic properties, we have characterized the murine IgG1 mAb (6E3) that was able to recognize the 2 main antigenic variants of NadA on the surface of MenB strains. The epitope targeted by mAb 6E3 was mapped by hydrogen-deuterium exchange mass spectrometry and shown to be located on the coiled-coil stalk region of NadA (aa 206-249). Although no serum bactericidal activity was observed for murine IgG1 mAb 6E3, functional activity was restored when using chimeric antibodies in which the variable regions of the murine mAb 6E3 were fused to human IgG3 constant regions, thus confirming the protective nature of the mAb 6E3 epitope. The use of chimeric antibody molecules will enable future investigations of complement-mediated antibody functionality independently of the Fc-mediated differences in complement activation. PMID:26304221

  17. Immunogenicity of IMS 1113 plus soluble subunit and chimeric proteins containing Mycoplasma hyopneumoniae P97 C-terminal repeat regions.

    Science.gov (United States)

    Barate, Abhijit K; Cho, Youngjae; Truong, Quang Lam; Hahn, Tae-Wook

    2014-03-01

    The surface adhesin P97 mediates the adherence of Mycoplasma hyopneumoniae to swine cilia. Two reiterated repeats R1 and R2 are located at the C-terminus of P97. The purpose of this study was to evaluate the immunogenicity of Montanide adjuvant IMS 1113 plus soluble subunit proteins rR1, rR1R2 and their chimeric forms coupled with B subunit of the heat-labile enterotoxin of Escherichia coli (LTB). Each recombinant protein in this study was capable of eliciting anti-R1 specific humoral antibodies (IgG), mucosal antibodies (IgG and IgA) and IFN-γ production. The chimeric protein rLTBR1R2 elicited the quickest humoral antibody response among the recombinant proteins. Serum and bronchoalveolar lavage analysis revealed that each recombinant protein was capable of inducing both Th1 and Th2 responses. Importantly, all of the proteins induced an anti-R1-specific Th2-biased response in both humoral and mucosal compartments, similar to the response observed in a natural infection or vaccination process. These observations indicate that rR1, rR1R2, rLTBR1 and rLTBR1R2 with IMS 1113 might represent a promising subunit vaccine strategy against porcine enzootic pneumonia in pigs. PMID:24461070

  18. Mutation of the fiber shaft heparan sulphate binding site of a 5/3 chimeric adenovirus reduces liver tropism.

    Science.gov (United States)

    Koski, Anniina; Karli, Eerika; Kipar, Anja; Escutenaire, Sophie; Kanerva, Anna; Hemminki, Akseli

    2013-01-01

    Natural tropism to the liver is a major obstacle in systemic delivery of adenoviruses in cancer gene therapy. Adenovirus binding to soluble coagulation factors and to cellular heparan sulphate proteoglycans via the fiber shaft KKTK domain are suggested to cause liver tropism. Serotype 5 adenovirus constructs with mutated KKTK regions exhibit liver detargeting, but they also transduce tumors less efficiently, possibly due to altered fiber conformation. We constructed Ad5/3lucS*, a 5/3 chimeric adenovirus with a mutated KKTK region. The fiber knob swap was hypothesized to facilitate tumor transduction. This construct was studied with or without additional coagulation factor ablation. Ad5/3lucS* exhibited significantly reduced transduction of human hepatic cells in vitro and mouse livers in vivo. Combination of coagulation factor ablation by warfarinization to Ad5/3lucS* seemed to further enhance liver detargeting. Cancer cell transduction by Ad5/3lucS* was retained in vitro. In vivo, viral particle accumulation in M4A4-LM3 xenograft tumors was comparable to controls, but Ad5/3lucS* transgene expression was nearly abolished. Coagulation factor ablation did not affect tumor transduction. These studies set the stage for further investigations into the effects of the KKTK mutation and coagulation factor ablation in the context of 5/3 serotype chimerism. Of note, the putative disconnect between tumor transduction and transgene expression could prove useful in further understanding of adenovirus biology. PMID:23585829

  19. Hepatitis Delta Virus: A Peculiar Virus

    OpenAIRE

    Carolina Alves; Cristina Branco; Celso Cunha

    2013-01-01

    The hepatitis delta virus (HDV) is distributed worldwide and related to the most severe form of viral hepatitis. HDV is a satellite RNA virus dependent on hepatitis B surface antigens to assemble its envelope and thus form new virions and propagate infection. HDV has a small 1.7 Kb genome making it the smallest known human virus. This deceivingly simple virus has unique biological features and many aspects of its life cycle remain elusive. The present review endeavors to gather the available ...

  20. Virus Infection

    Directory of Open Access Journals (Sweden)

    Hiroshi Abe

    2013-01-01

    Full Text Available Of 168 patients with chronic hepatitis B virus (HBV infection-related liver disease, 20 patients who had received 100 mg of lamivudine plus 10 mg/day of adefovir dipivoxil (ADV (ADV group and 124 patients who had received 0.5 mg/day of entecavir or 100 mg/day of lamivudine (non-ADV group for >1 year were enrolled. For comparative analyses, 19 well-matched pairs were obtained from the groups by propensity scores. At the time of enrollment, serum creatinine and phosphate concentrations were similar between the ADV and non-ADV groups; however, urinary phosphate ( and serum bone-specific alkaline phosphatase (BAP ( concentrations were significantly higher in the ADV group than in the non-ADV group. Serum BAP was significantly higher at the time of enrollment than before ADV administration in the ADV group (, although there was no significant change in serum BAP concentration in the non-ADV group. There was a significant positive correlation between the period of ADV therapy and ΔBAP (, . Serum BAP concentration increased before increase in serum creatinine concentration and was useful for early detection of adverse events and for developing adequate measures for continuing ADV for chronic HBV infection-related liver disease.

  1. I-131 rituximab (chimeric anti Cd 20 mab) radioimmunotherapy of non-Hodgkins lymphoma

    International Nuclear Information System (INIS)

    radioimmunotherapy rather than antibody-targeted internal radiotherapy. Such treatment in 90 patients with relapsed/refractory follicular (grade I, II, III) (78) MALT (5) and small lymphocytic (7) lymphoma with 3 (1-8) median prior chemo-therapies, 60% stage III/IV, resulted in complete remission CR) in 51% and partial response (PR) in 23% for an overall response rate (ORR) of 74%. In contrast to radiolabelled murine antibodies, the 131I-rituximab chimeric monoclonal antibody does not cause any immunogenic HAMA host response and repeated courses of 131I-rituximab radioimmunotherapy may be given for subsequent relapse. The median duration of response was 22 months in our patients who achieved CR and retreatment was performed in 8 patients, the majority of whom responded again to the repeat 131I-rituximab radioimmunotherapy. Median progression-free survival in our patients was 13 months and the 4 year actuarial survival of all our treated patients after 131I-rituximab radioimmunotherapy for non-Hodgkins lymphoma was 63%. Non-myeloablative radioimmunotherapy of mantle cell non-Hodgkins lymphoma with 131I-rituximab showed CR in 2 of 8 patients, but the reported results of myeloablative regimens and autologous stem cell rescue demonstrate CR in 6 or 7 patients after 131I-rituximab treatment. Indolent non-Hodgkins lymphoma which transforms into more aggressive forms may also be treated with a myeloablative regimen combining standard dose 131I-rituximab radioimmunotherapy with BEAM chemotherapy for conditioning prior to stem cell autograft at 16 days. Three patients with transformed non-Hodgkins lymphoma treated with 131I-rituximab, BEAM chemotherapy and stem cell rescue all achieved CR of duration of at least 12 months. Refractory or relapsed aggressive non-Hodgkins lymphoma such as DLCBL may also be treated with non-myeloablative protocols complemented by long-term consolidation and maintenance MabThera immunotherapy, currently in clinical trial. Greater experience has been obtained with

  2. Hepatitis virus panel

    Science.gov (United States)

    The hepatitis virus panel is a series of blood tests used to detect current or past infection by hepatitis A , hepatitis ... samples for more than one kind of hepatitis virus at the same time. Antibody and antigen tests ...

  3. Human Parainfluenza Viruses

    Science.gov (United States)

    ... Search The CDC Cancel Submit Search The CDC Human Parainfluenza Viruses (HPIVs) Note: Javascript is disabled or ... CDC.gov . Recommend on Facebook Tweet Share Compartir Human parainfluenza viruses (HPIVs) commonly cause respiratory illnesses in ...

  4. Tumorigenic DNA viruses

    Energy Technology Data Exchange (ETDEWEB)

    Klein, G.

    1989-01-01

    The eighth volume of Advances in Viral Oncology focuses on the three major DNA virus groups with a postulated or proven tumorigenic potential: papillomaviruses, animal hepatitis viruses, and the Epstein-Bar virus. In the opening chapters, the contributors analyze the evidence that papillomaviruses and animal hepatitis viruses are involved in tumorigenesis and describe the mechanisms that trigger virus-host cell interactions. A detailed section on the Epstein-Barr virus (EBV) - comprising more than half the book - examines the transcription and mRNA processing patterns of the virus genome; the mechanisms by which EBV infects lymphoid and epithelial cells; the immunological aspects of the virus; the actions of EBV in hosts with Acquired Immune Deficiency Syndrome; and the involvement of EBV in the etiology of Burkitt's lymphoma.

  5. Viruses and Breast Cancer

    International Nuclear Information System (INIS)

    Viruses are the accepted cause of many important cancers including cancers of the cervix and anogenital area, the liver, some lymphomas, head and neck cancers and indirectly human immunodeficiency virus associated cancers. For over 50 years, there have been serious attempts to identify viruses which may have a role in breast cancer. Despite these efforts, the establishment of conclusive evidence for such a role has been elusive. However, the development of extremely sophisticated new experimental techniques has allowed the recent development of evidence that human papilloma virus, Epstein-Barr virus, mouse mammary tumor virus and bovine leukemia virus may each have a role in the causation of human breast cancers. This is potentially good news as effective vaccines are already available to prevent infections from carcinogenic strains of human papilloma virus, which causes cancer of the uterine cervix

  6. Viruses and human cancer

    Energy Technology Data Exchange (ETDEWEB)

    Gallo, R.C.; Haseltine, W.; Klein, G.; Zur Hausen, H.

    1987-01-01

    This book contains papers on the following topics: Immunology and Epidemiology, Biology and Pathogenesis, Models of Pathogenesis and Treatment, Simian and Bovine Retroviruses, Human Papilloma Viruses, EBV and Herpesvirus, and Hepatitis B Virus.

  7. Herpes Simplex Virus (HSV)

    Science.gov (United States)

    ... rashes clinical tools newsletter | contact Share | Herpes Simplex Virus (HSV) A parent's guide to condition and treatment ... skin or mouth sores with the herpes simplex virus (HSV) is called primary herpes. This may be ...

  8. Hepatitis virus panel

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003558.htm Hepatitis virus panel To use the sharing features on this page, please enable JavaScript. The hepatitis virus panel is a series of blood tests used ...

  9. Viruses and Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lawson, James S., E-mail: james.lawson@unsw.edu.au; Heng, Benjamin [School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney (Australia)

    2010-04-30

    Viruses are the accepted cause of many important cancers including cancers of the cervix and anogenital area, the liver, some lymphomas, head and neck cancers and indirectly human immunodeficiency virus associated cancers. For over 50 years, there have been serious attempts to identify viruses which may have a role in breast cancer. Despite these efforts, the establishment of conclusive evidence for such a role has been elusive. However, the development of extremely sophisticated new experimental techniques has allowed the recent development of evidence that human papilloma virus, Epstein-Barr virus, mouse mammary tumor virus and bovine leukemia virus may each have a role in the causation of human breast cancers. This is potentially good news as effective vaccines are already available to prevent infections from carcinogenic strains of human papilloma virus, which causes cancer of the uterine cervix.

  10. Taming influenza viruses

    OpenAIRE

    Ozawa, Makoto; Kawaoka, Yoshihiro

    2011-01-01

    Plasmid-based reverse genetics systems allow the artificial generation of viruses with cloned cDNA-derived genomes. Since the establishment of such systems for influenza virus, numerous attempts have been made to tame this pathogenic agent. In particular, several types of viruses expressing foreign genes have been generated and used to further our knowledge of influenza virus replication and pathogenicity and to develop novel influenza vaccines. Here, we review these achievements and discuss ...

  11. Understanding Ebola Virus Transmission

    OpenAIRE

    Seth Judson; Joseph Prescott; Vincent Munster

    2015-01-01

    An unprecedented number of Ebola virus infections among healthcare workers and patients have raised questions about our understanding of Ebola virus transmission. Here, we explore different routes of Ebola virus transmission between people, summarizing the known epidemiological and experimental data. From this data, we expose important gaps in Ebola virus research pertinent to outbreak situations. We further propose experiments and methods of data collection that will enable scientists to fil...

  12. Hepatitis D Virus Replication.

    Science.gov (United States)

    Taylor, John M

    2015-11-01

    This work reviews specific related aspects of hepatitis delta virus (HDV) reproduction, including virion structure, the RNA genome, the mode of genome replication, the delta antigens, and the assembly of HDV using the envelope proteins of its helper virus, hepatitis B virus (HBV). These topics are considered with perspectives ranging from a history of discovery through to still-unsolved problems. HDV evolution, virus entry, and associated pathogenic potential and treatment of infections are considered in other articles in this collection. PMID:26525452

  13. Lifestyles of plant viruses

    OpenAIRE

    Roossinck, Marilyn J.

    2010-01-01

    The vast majority of well-characterized eukaryotic viruses are those that cause acute or chronic infections in humans and domestic plants and animals. However, asymptomatic persistent viruses have been described in animals, and are thought to be sources for emerging acute viruses. Although not previously described in these terms, there are also many viruses of plants that maintain a persistent lifestyle. They have been largely ignored because they do not generally cause disease. The persisten...

  14. Efficient generation of recombinant RNA viruses using targeted recombination-mediated mutagenesis of bacterial artificial chromosomes containing full-length cDNA

    DEFF Research Database (Denmark)

    Rasmussen, Thomas Bruun; Risager, Peter Christian; Fahnøe, Ulrik;

    2013-01-01

    Background Infectious cDNA clones are a prerequisite for directed genetic manipulation of RNA viruses. Here, a strategy to facilitate manipulation and rescue of classical swine fever viruses (CSFVs) from full-length cDNAs present within bacterial artificial chromosomes (BACs) is described. This...... strategy allows manipulation of viral cDNA by targeted recombination-mediated mutagenesis within bacteria. Results A new CSFV-BAC (pBeloR26) derived from the Riems vaccine strain has been constructed and subsequently modified in the E2 coding sequence, using the targeted recombination strategy to enable...... rescue of chimeric pestiviruses (vR26_E2gif and vR26_TAV) with potential as new marker vaccine candidates. Sequencing of the BACs revealed a high genetic stability during passages within bacteria. The complete genome sequences of rescued viruses, after extensive passages in mammalian cells showed that...

  15. Chikungunya virus, Cameroon, 2006

    OpenAIRE

    Peyrefitte, Christophe N.; Rousset, Dominique; Pastorino, Boris A.M.; Pouillot, Regis; Bessaud, Maël; Tock, Fabienne; Mansaray, Helene; Merle, Olivier L.; Pascual, Aurelie M.; Paupy, Christophe; Vessiere, Aurelia; Imbert, Patrice; Tchendjou, Patrice; Durand, Jean-Paul; Tolou, Hugues J.

    2007-01-01

    We report the isolation of chikungunya virus from a patient during an outbreak of a denguelike syndrome in Cameroon in 2006. The virus was phylogenetically grouped in the Democratic Republic of the Congo cluster, indicating a continuous circulation of a genetically similar chikungunya virus population during 6 years in Central Africa.

  16. Computer Virus Protection

    Science.gov (United States)

    Rajala, Judith B.

    2004-01-01

    A computer virus is a program--a piece of executable code--that has the unique ability to replicate. Like biological viruses, computer viruses can spread quickly and are often difficult to eradicate. They can attach themselves to just about any type of file, and are spread by replicating and being sent from one individual to another. Simply having…

  17. What's West Nile Virus?

    Science.gov (United States)

    ... Help White House Lunch Recipes What's West Nile Virus? KidsHealth > For Kids > What's West Nile Virus? Print A A A Text Size en español ¿Qué es el Virus del Nilo Occidental? What exactly is the West ...

  18. Respiratory Syncytial Virus

    Science.gov (United States)

    ... Things to Know About Zika & Pregnancy Respiratory Syncytial Virus KidsHealth > For Parents > Respiratory Syncytial Virus Print A A A Text Size What's in ... RSV When to Call the Doctor en español Virus respiratorio sincitial About RSV Respiratory syncytial (sin-SISH- ...

  19. BOVINE VIRAL DIARRHEA VIRUSES

    Science.gov (United States)

    Bovine viral diarrhea virus (BVDV) is an umbrella term for two species of viruses, BVDV1 and BVDV2, within the Pestivirus genus of the Flavivirus family. BVDV viruses are further subclassified as cytopathic and noncytopathic based on their activity in cultured epithelial cells. Noncytopathic BVDV p...

  20. Chimeric anti-staphylococcal enterotoxin B antibodies and lovastatin act synergistically to provide in vivo protection against lethal doses of SEB.

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    Mulualem E Tilahun

    Full Text Available Staphylococcal enterotoxin B (SEB is one of a family of toxins secreted by Staphylococcus aureus that act as superantigens, activating a large fraction of the T-cell population and inducing production of high levels of inflammatory cytokines that can cause toxic shock syndrome (TSS and death. Extracellular engagement of the TCR of T-cells and class II MHC of antigen presenting cells by SEB triggers the activation of many intracellular signaling processes. We engineered chimeric antibodies to block the extracellular engagement of cellular receptors by SEB and used a statin to inhibit intracellular signaling. Chimeric human-mouse antibodies directed against different neutralizing epitopes of SEB synergistically inhibited its activation of human T-cells in vitro. In the in vivo model of lethal toxic shock syndrome (TSS in HLA-DR3 transgenic mice, two of these antibodies conferred significant partial protection when administered individually, but offered complete protection in a synergistic manner when given together. Similarly, in vivo, lovastatin alone conferred only partial protection from TSS similar to single anti-SEB antibodies. However, used in combination with one chimeric neutralizing anti-SEB antibody, lovastatin provided complete protection against lethal TSS in HLA-DR3 transgenic mice. These experiments demonstrate that in vivo protection against lethal doses of SEB can be achieved by a statin of proven clinical safety and chimeric human-mouse antibodies, agents now widely used and known to be of low immunogenicity in human hosts.