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Sample records for attenuated oncolytic recombinant

  1. Recombinant immunomodulating lentogenic or mesogenic oncolytic newcastle disease virus for treatment of pancreatic adenocarcinoma

    NARCIS (Netherlands)

    P.R.A. Buijs (Pascal); S. van Nieuwkoop (Stefan); Vaes, V. (Vincent); R.A.M. Fouchier (Ron); C.H.J. van Eijck (Casper); B.G. van den Hoogen (Bernadette)

    2015-01-01

    textabstractOncolytic Newcastle disease virus (NDV) might be a promising new therapeutic agent for the treatment of pancreatic cancer. We evaluated recombinant NDVs (rNDVs) expressing interferon (rNDV-hIFNβ-F0) or an IFN antagonistic protein (rNDV-NS1-F0), as well as rNDV with

  2. Current good manufacturing practice production of an oncolytic recombinant vesicular stomatitis viral vector for cancer treatment.

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    Ausubel, L J; Meseck, M; Derecho, I; Lopez, P; Knoblauch, C; McMahon, R; Anderson, J; Dunphy, N; Quezada, V; Khan, R; Huang, P; Dang, W; Luo, M; Hsu, D; Woo, S L C; Couture, L

    2011-04-01

    Vesicular stomatitis virus (VSV) is an oncolytic virus currently being investigated as a promising tool to treat cancer because of its ability to selectively replicate in cancer cells. To enhance the oncolytic property of the nonpathologic laboratory strain of VSV, we generated a recombinant vector [rVSV(MΔ51)-M3] expressing murine gammaherpesvirus M3, a secreted viral chemokine-binding protein that binds to a broad range of mammalian chemokines with high affinity. As previously reported, when rVSV(MΔ51)-M3 was used in an orthotopic model of hepatocellular carcinoma (HCC) in rats, it suppressed inflammatory cell migration to the virus-infected tumor site, which allowed for enhanced intratumoral virus replication leading to increased tumor necrosis and substantially prolonged survival. These encouraging results led to the development of this vector for clinical translation in patients with HCC. However, a scalable current Good Manufacturing Practice (cGMP)-compliant manufacturing process has not been described for this vector. To produce the quantities of high-titer virus required for clinical trials, a process that is amenable to GMP manufacturing and scale-up was developed. We describe here a large-scale (50-liter) vector production process capable of achieving crude titers on the order of 10(9) plaque-forming units (PFU)/ml under cGMP. This process was used to generate a master virus seed stock and a clinical lot of the clinical trial agent under cGMP with an infectious viral titer of approximately 2 × 10(10) PFU/ml (total yield, 1 × 10(13) PFU). The lot has passed all U.S. Food and Drug Administration-mandated release testing and will be used in a phase 1 clinical translational trial in patients with advanced HCC.

  3. Intratumoral modulation of the inducible co-stimulator ICOS by recombinant oncolytic virus promotes systemic anti-tumour immunity

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    Zamarin, Dmitriy; Holmgaard, Rikke B.; Ricca, Jacob; Plitt, Tamar; Palese, Peter; Sharma, Padmanee; Merghoub, Taha; Wolchok, Jedd D.; Allison, James P.

    2017-01-01

    Emerging data suggest that locoregional cancer therapeutic approaches with oncolytic viruses can lead to systemic anti-tumour immunity, although the appropriate targets for intratumoral immunomodulation using this strategy are not known. Here we find that intratumoral therapy with Newcastle disease virus (NDV), in addition to the activation of innate immunity, upregulates the expression of T-cell co-stimulatory receptors, with the inducible co-stimulator (ICOS) being most notable. To explore ICOS as a direct target in the tumour, we engineered a recombinant NDV-expressing ICOS ligand (NDV-ICOSL). In the bilateral flank tumour models, intratumoral administration of NDV-ICOSL results in enhanced infiltration with activated T cells in both virus-injected and distant tumours, and leads to effective rejection of both tumours when used in combination with systemic CTLA-4 blockade. These findings highlight that intratumoral immunomodulation with an oncolytic virus expressing a rationally selected ligand can be an effective strategy to drive systemic efficacy of immune checkpoint blockade. PMID:28194010

  4. Evaluation of a new recombinant oncolytic vaccinia virus strain GLV-5b451 for feline mammary carcinoma therapy.

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    Marion Adelfinger

    Full Text Available Virotherapy on the basis of oncolytic vaccinia virus (VACV infection is a promising approach for cancer therapy. In this study we describe the establishment of a new preclinical model of feline mammary carcinoma (FMC using a recently established cancer cell line, DT09/06. In addition, we evaluated a recombinant vaccinia virus strain, GLV-5b451, expressing the anti-vascular endothelial growth factor (VEGF single-chain antibody (scAb GLAF-2 as an oncolytic agent against FMC. Cell culture data demonstrate that GLV-5b451 virus efficiently infected, replicated in and destroyed DT09/06 cancer cells. In the selected xenografts of FMC, a single systemic administration of GLV-5b451 led to significant inhibition of tumor growth in comparison to untreated tumor-bearing mice. Furthermore, tumor-specific virus infection led to overproduction of functional scAb GLAF-2, which caused drastic reduction of intratumoral VEGF levels and inhibition of angiogenesis. In summary, here we have shown, for the first time, that the vaccinia virus strains and especially GLV-5b451 have great potential for effective treatment of FMC in animal model.

  5. Oncolytic Adenoviruses in Cancer Treatment

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    Ramon Alemany

    2014-02-01

    Full Text Available The therapeutic use of viruses against cancer has been revived during the last two decades. Oncolytic viruses replicate and spread inside tumors, amplifying their cytotoxicity and simultaneously reversing the tumor immune suppression. Among different viruses, recombinant adenoviruses designed to replicate selectively in tumor cells have been clinically tested by intratumoral or systemic administration. Limited efficacy has been associated to poor tumor targeting, intratumoral spread, and virocentric immune responses. A deeper understanding of these three barriers will be required to design more effective oncolytic adenoviruses that, alone or combined with chemotherapy or immunotherapy, may become tools for oncologists.

  6. Application Progress of Recombinant Attenuated Listeria monocytogenes in Tumor Immunotherapy

    Institute of Scientific and Technical Information of China (English)

    Yin Xiaojiao; Bai Lin; Yang Xu

    2015-01-01

    Much progress of application of bacterial vaccine in treatment and prevention of tumor was acquired,which showed broad prospect in clinical study of animals and humans. Listeria monocytogenes( L. monocytogenes) was considered much important by virtue of its special characteristic of biology and immunology.L. monocytogenes was ingested by professional or part-time phagocytes,survived and proliferated in the phagocytes under synergism of toxic factor secreted by itself,meanwhile,the cellular and humoral immune response was induced. Antigenic gene of specific tumor was loaded in the attenuated L. monocytogenes,which can enhance immune response of host cells. Effective cell targeted to enter tumor tissue and acted on tumor cells to induce apoptosis of tumor cells. Tumor degenerated not easy to reappear. Therefore,recombinant attenuated L. monocytogenes was a safe and effective anti-cancer vaccine vector. Now the work of researchers mainly focuses on solving practical problem in clinical application. Biological characteristics of L. monocytogenes,feasibility and superiority of L. monocytogenes as targeted vaccine vector,problem and prospect of L. monocytogenes in clinical application of anti-tumor were reviewed in this paper.

  7. Regression of Human Prostate Tumors and Metastases in Nude Mice following Treatment with the Recombinant Oncolytic Vaccinia Virus GLV-1h68

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    Ivaylo Gentschev

    2010-01-01

    Full Text Available Virotherapy using oncolytic vaccinia virus strains is one of the most promising new strategies for cancer therapy. In the current study, we analyzed the therapeutic efficacy of the oncolytic vaccinia virus GLV-1h68 against two human prostate cancer cell lines DU-145 and PC-3 in cell culture and in tumor xenograft models. By viral proliferation assays and cell survival tests, we demonstrated that GLV-1h68 was able to infect, replicate in, and lyse these prostate cancer cells in culture. In DU-145 and PC-3 tumor xenograft models, a single intravenous injection with GLV-1h68 resulted in a significant reduction of primary tumor size. In addition, the GLV-1h68-infection led to strong inflammatory and oncolytic effects resulting in drastic reduction of regional lymph nodes with PC-3 metastases. Our data documented that the GLV-1h68 virus has a great potential for treatment of human prostate carcinoma.

  8. Using recombinant DNA technology for the development of live-attenuated dengue vaccines.

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    Lee, Hsiang-Chi; Butler, Michael; Wu, Suh-Chin

    2012-07-15

    Dramatic increases in dengue (DEN) incidence and disease severity have been reported, in great part due to the geographic expansion of Aedes aegypti and Aedes albopictus mosquitoes. One result is the expanded co-circulation of all dengue 1-4 serotype viruses (DENV) in urban areas worldwide, especially in South and South-East Asia, and South America. DEN disease severity ranges from asymptomatic infections to febrile dengue fevers (DF) to life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). There is an urgent need for a safe and effective tetravalent DEN vaccine. Several live attenuated, tetravalent DEN vaccine candidates have been generated by recombinant DNA technology; these candidates are capable of providing immunity to all four DENV serotypes. In this paper we review (a) recombinant live-attenuated DEN vaccine candidates in terms of deletion, antigen chimerization, and the introduction of adaptive mutations; (b) strategies for improving tetravalent vaccine attenuation; and (c) live-attenuated DENV vaccine development.

  9. Construction of a recombinant attenuated Salmonella typhimurium DNA vaccine carrying Helicobacter pylori hpaA

    Institute of Scientific and Technical Information of China (English)

    Can Xu; Zhao-Shen Li; Yi-Qi Du; Zhen-Xing Tu; Yan-Fang Gong; Jing Jin; Hong-Yu Wu; Guo-Ming Xu

    2005-01-01

    AIM: To construct a recombinant attenuated Salmonella typhimurium DNA vaccine carrying Helicobacter pylori hpaA gene and to detect its immunogenicity.METHODS: Genomic DNA of the standard H pylori strain 17 874 was isolated as the template, hpaA gene fragment was amplified by polymerase chain reaction (PCR) and cloned into pUCmT vector. DNA sequence of the amplified hpaA gene was assayed, then cloned into the eukaryotic expression vector pIRES through enzyme digestion and ligation reactions. The recombinant plasmid was used to transform competent Escherichia coliDH5α, and the positive clones were screened by PCR and restriction enzyme digestion. Then, the recombinant pIRES-hpaA was used to transform LB5000 and the recombinant plasmid isolated from LB5000 was finally used to transform SL7207. After that, the recombinant strain was grown in vitrorepeatedly. In order to iclentify the immunogenicity of the vaccinein vitro, the recombinant pIRES-hpaA was transfected to COS-7 cells using LipofectamineTM2000, the immunogenicity of expressed HpaA protein was detected with SDS-PAGE and Western blot.RESULTS: The 750-base pair hpaA gene fragment was amplified from the genomic DNA and was consistent with the sequence of H pylori hpaA by sequence analysis. It was confirmed by PCR and restriction enzyme digestion that H pylori hpaA gene was inserted into the eukaryotic expression vector pIRES and a stable recombinant live attenuated Salmonella typhimurium DNA vaccine carrying H pylori hpaA gene was successfully constructed and the specific strip of HpaA expressed by pIRES-hpaA was detected through Western blot.CONCLUSION: The recombinant attenuated Salmonella typhimurium DNA vaccine strain expressing HpaA protein with immunogenicity can be constructed and it may be helpful for further investigating the immune action of DNA vaccine in vivo.

  10. Plant recombinant erythropoietin attenuates inflammatory kidney cell injury.

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    Conley, Andrew J; Mohib, Kanishka; Jevnikar, Anthony M; Brandle, Jim E

    2009-02-01

    Human erythropoietin (EPO) is a pleiotropic cytokine with remarkable tissue-protective activities in addition to its well-established role in red blood cell production. Unfortunately, conventional mammalian cell cultures are unlikely to meet the anticipated market demands for recombinant EPO because of limited capacity and high production costs. Plant expression systems may address these limitations to enable practical, cost-effective delivery of EPO in tissue injury prevention therapeutics. In this study, we produced human EPO in tobacco and demonstrated that plant-derived EPO had tissue-protective activity. Our results indicated that targeting to the endoplasmic reticulum (ER) provided the highest accumulation levels of EPO, with a yield approaching 0.05% of total soluble protein in tobacco leaves. The codon optimization of the human EPO gene for plant expression had no clear advantage; furthermore, the human EPO signal peptide performed better than a tobacco signal peptide. In addition, we found that glycosylation was essential for the stability of plant recombinant EPO, whereas the presence of an elastin-like polypeptide fusion had a limited positive impact on the level of EPO accumulation. Confocal microscopy showed that apoplast and ER-targeted EPO were correctly localized, and N-glycan analysis demonstrated that complex plant glycans existed on apoplast-targeted EPO, but not on ER-targeted EPO. Importantly, plant-derived EPO had enhanced receptor-binding affinity and was able to protect kidney epithelial cells from cytokine-induced death in vitro. These findings demonstrate that tobacco plants may be an attractive alternative for the production of large amounts of biologically active EPO.

  11. An Overview of Live Attenuated Recombinant Pseudorabies Viruses for Use as Novel Vaccines

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    Bo Dong

    2014-01-01

    Full Text Available Pseudorabies virus (PRV is a double-stranded, DNA-based swine virus with a genome approximating 150 kb in size. PRV has many nonessential genes which can be replaced with genes encoding heterologous antigens but without deleterious effects on virus propagation. Recombinant PRVs expressing both native and foreign antigens are able to stimulate immune responses. In this paper, we review the current status of live attenuated recombinant PRVs and live PRV-based vector vaccines with potential for controlling viral infections in animals.

  12. CRISPR-Cas9 as a Powerful Tool for Efficient Creation of Oncolytic Viruses.

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    Yuan, Ming; Webb, Eika; Lemoine, Nicholas Robert; Wang, Yaohe

    2016-03-07

    The development of oncolytic viruses has led to an emerging new class of cancer therapeutics. Although the safety profile has been encouraging, the transition of oncolytic viruses to the clinical setting has been a slow process due to modifications. Therefore, a new generation of more potent oncolytic viruses needs to be exploited, following our better understanding of the complex interactions between the tumor, its microenvironment, the virus, and the host immune response. The conventional method for creation of tumor-targeted oncolytic viruses is based on homologous recombination. However, the creation of new mutant oncolytic viruses with large genomes remains a challenge due to the multi-step process and low efficiency of homologous recombination. The CRISPR-associated endonuclease Cas9 has hugely advanced the potential to edit the genomes of various organisms due to the ability of Cas9 to target a specific genomic site by a single guide RNA. In this review, we discuss the CRISPR-Cas9 system as an efficient viral editing method for the creation of new oncolytic viruses, as well as its potential future applications in the development of oncolytic viruses. Further, this review discusses the potential of off-target effects as well as CRISPR-Cas9 as a tool for basic research into viral biology.

  13. 重组复制型溶瘤腺病毒p53的质量控制方法%Quality control of recombinant oncolytic adenovirus/p53

    Institute of Scientific and Technical Information of China (English)

    高凯; 毕华; 丁有学; 李永红; 韩春梅; 郭莹; 饶春明

    2011-01-01

    replication ability of recombinant virus was determined by TCID50 titer ratio of filial generation virus between human lung cancer cell A549 and human diploid epidermal fibrolast BJ cells after infected by virus with same MOI. TCID50 titer ratio of tumor cell infection group to normal cell infection control group was 398. The IE-HPLC purity of virus was 99.5%. There was less than 1 copy of wild type adenovirus within 1×107 VP recombinant virus. Other quality control items were complied with corresponding requirements in the guidance for human somatic cell therapy and gene therapy and Chinese pharmacopeia volume III. The detection method of oncolytic adenovirus/p53 was successfully established for quality control standard. The study also provided reference for quality control of other oncolytic viral vector products.

  14. Novel oncolytic viral therapies in patients with thoracic malignancies

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    Ahmad Z

    2016-12-01

    Full Text Available Zeeshan Ahmad, Robert A Kratzke Department of Medicine, Division of Hematology, Oncology, and Transplantation, University of Minnesota Medical School, Minneapolis, MN, USA Abstract: Oncolytic virotherapy is the use of replication-competent viruses to treat malignancies. The potential of oncolytic virotherapy as an approach to cancer therapy is based on historical evidence that certain viral infections can cause spontaneous remission of both hematologic and solid tumor malignancies. Oncolytic virotherapy may eliminate cancer cells through either direct oncolysis of infected tumor cells or indirect immune-mediated oncolysis of uninfected tumor cells. Recent advances in oncolytic virotherapy include the development of a wide variety of genetically attenuated RNA viruses with precise cellular tropism and the identification of cell-surface receptors that facilitate viral transfer to the tissue of interest. Current research is also focused on targeting metastatic disease by sustaining the release of progeny viruses from infected tumor cells and understanding indirect tumor cell killing through immune-mediated mechanisms of virotherapy. The purpose of this review is to critically evaluate recent evidence on the clinical development of tissue-specific viruses capable of targeting tumor cells and eliciting secondary immune responses in lung cancers and mesothelioma. Keywords: lung cancer, mesothelioma, VSV, adenovirus, measles

  15. Recombinant Bcl-xL attenuates vascular hyperpermeability in a rat model of hemorrhagic shock

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    Tharakan, B; McNeal, SI; Hunter, FA; Sawant, DA; Smythe, WR; Childs, EW

    2015-01-01

    Following hemorrhagic shock (HS), vascular hyperpermeability, that is, the leakage of fluid, nutrients and proteins into the extravascular space occurs primarily due to the disruption of the endothelial cell–cell adherens junctional complex. Studies from our laboratory demonstrate that activation of the mitochondria-mediated ‘intrinsic’ apoptotic signaling cascade has a significant role in modulating HS-induced hyperpermeability. Here we report the novel use of recombinant Bcl-xL, an anti-apoptotic protein, to control HS-induced vascular hyperpermeability. Our results corroborate involvement of vascular hyperpermeability and apoptotic signaling. HS (the mean arterial pressure (MAP) was reduced to 40 mm Hg for 60 min followed by resuscitation to 90 mm Hg for 60 min) in rats resulted in vascular hyperpermeability as determined by intravital microscopy. Treatment of Bcl-xL (2.5 µg/ml of rat blood in non-lipid cationic polymer, i.v.) before, during and even after HS attenuated or reversed HS-induced vascular hyperpermeability significantly (P<0.05). Conversely, treatment using Bcl-xL inhibitors, 2-methoxy antimycin (2-OMeAA) and ABT 737, significantly increased vascular hyperpermeability compared with sham (P<0.05). Bcl-xL treatment also decreased the amount of fluid volume required to maintain a MAP of 90 mm Hg during resuscitation (P<0.05). HS resulted in an increased mitochondrial reactive oxygen species formation, reduction of ΔΨm, mitochondrial release of cytochrome c and significant activation of caspase-3 (P<0.05). All of these effects were significantly inhibited by Bcl-xL pre-treatment (P<0.05). Our results show that recombinant Bcl-xL is effective against HS-induced vascular hyperpermeability that appears to be mediated through the preservation of ΔΨm and subsequent prevention of caspase-3 activation. PMID:27042339

  16. Induction of influenza-specific mucosal immunity by an attenuated recombinant Sendai virus.

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    Thuc-vy L Le

    Full Text Available BACKGROUND: Many pathogens initiate infection at the mucosal surfaces; therefore, induction of mucosal immune responses is a first level of defense against infection and is the most powerful means of protection. Although intramuscular injection is widely used for vaccination and is effective at inducing circulating antibodies, it is less effective at inducing mucosal antibodies. METHODOLOGY/PRINCIPAL FINDINGS: Here we report a novel recombinant, attenuated Sendai virus vector (GP42-H1 in which the hemagglutinin (HA gene of influenza A virus was introduced into the Sendai virus genome as an additional gene. Infection of CV-1 cells by GP42-H1 resulted in cell surface expression of the HA protein. Intranasal immunization of mice with 1,000 plaque forming units (pfu of GP42-H1 induced HA-specific IgG and IgA antibodies in the blood, bronchoalveolar lavage fluid, fecal pellet extracts and saliva. The HA-specific antibody titer induced by GP42-H1 closely resembles the titer induced by sublethal infection by live influenza virus; however, in contrast to infection by influenza virus, immunization with GP42-H1 did not result in disease symptoms or the loss of body weight. In mice that were immunized with GP42-H1 and then challenged with 5LD(50 (1250 pfu of influenza virus, no significant weight loss was observed and other visual signs of morbidity were not detected. CONCLUSIONS: These results demonstrate that the GP42-H1 Sendai virus recombinant is able to confer full protection from lethal infection by influenza virus, supporting the conclusion that it is a safe and effective mucosal vaccine vector.

  17. Systemic immune responses to oral administration of recombinant attenuated Salmonella typhimurium expressing Helicobacter pyloriurease in mice

    Institute of Scientific and Technical Information of China (English)

    Xiao-Feng Liu; Jia-Lu Hu; Qi-Zheng Quan; Zi-Qin Sun; Yao-Jun Wang; Feng Qi

    2005-01-01

    AIM: To evaluate whether attenuated Salmonellatyphimurium producing Helicobacter pylori ( H pylori) urease subunit B (UreB) could induce systemic immune responses against H pylori infection.METHODS: Attenuated S. typhimurium SL3261 was used as a live carrier of plasmid pTC01-UreB, which encodes recombinant H pylori UreB protein. Balb/c mice were given oral immunization with two doses of SL3261/pTC01-UreBat a 3-wk interval. Twelve weeks after oral immunization of mice, serum IgG antibodies were evaluated by ELISA assay. Gamma interferon (IFN-γ) and interleukin 10 (IL-10)in the supernatant of spleen cell culture were also assessed by ELISA.RESULTS: After oral immunization of mice, serum specific IgG antibodies against UreB in vaccine group were much higher than that in PBS and native Salmonella SL3261control groups (A450, 0.373±0.100 vs 0.053±0.022, 0.142±0.039, respectively, P<0.01). Moreover, IFN-γ in vaccine group was on average 167.53±29.93 pg/mL, which showed a significant increase vs that of PBS control group (35.68±3.55 pg/mL, P<0.01). There was also a tremendous increase of IL-L0 in vaccine group compared to PBS and SL3261 control groups (275.13±27.65 pg/mL vs 56.00±7.15 pg/mL, 68.02±15.03 pg/mL, respectively, P<0.01). In addition, no obvious side effects in mice and no change in gastric inflammation were observed. CONCLUSION: The multiple oral immunizations with the attenuated S. typhimurium expressing H pylori UreB could induce significant systemic immune responses, suggesting it may be used as oral vaccine against H pylori infection.

  18. Oncolytic virus therapy for cancer.

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    Goldufsky, Joe; Sivendran, Shanthi; Harcharik, Sara; Pan, Michael; Bernardo, Sebastian; Stern, Richard H; Friedlander, Philip; Ruby, Carl E; Saenger, Yvonne; Kaufman, Howard L

    2013-01-01

    The use of oncolytic viruses to treat cancer is based on the selection of tropic tumor viruses or the generation of replication selective vectors that can either directly kill infected tumor cells or increase their susceptibility to cell death and apoptosis through additional exposure to radiation or chemotherapy. In addition, viral vectors can be modified to promote more potent tumor cell death, improve the toxicity profile, and/or generate host antitumor immunity. A variety of viruses have been developed as oncolytic therapeutics, including adenovirus, vaccinia virus, herpesvirus, coxsackie A virus, Newcastle disease virus, and reovirus. The clinical development of oncolytic viral therapy has accelerated in the last few years, with several vectors entering clinical trials for a variety of cancers. In this review, current strategies to optimize the therapeutic effectiveness and safety of the major oncolytic viruses are discussed, and a summary of current clinical trials is provided. Further investigation is needed to characterize better the clinical impact of oncolytic viruses, but there are increasing data demonstrating the potential promise of this approach for the treatment of human and animal cancers.

  19. Oncolytic viruses as anticancer vaccines

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    Norman eWoller

    2014-07-01

    Full Text Available Oncolytic virotherapy has shown impressive results in preclinical studies and first promising therapeutic outcomes in clinical trials as well. Since viruses are known for a long time as excellent vaccination agents, oncolytic viruses are now designed as novel anticancer agents combining the aspect of lysis-dependent cytoreductive activity with concomitant induction of antitumoral immune responses. Antitumoral immune activation by oncolytic virus infection of tumor tissue comprises both, immediate effects of innate immunity and also adaptive responses for long lasting antitumoral activity which is regarded as the most prominent challenge in clinical oncology. To date, the complex effects of a viral tumor infection on the tumor microenvironment and the consequences for the tumor-infiltrating immune cell compartment are poorly understood. However, there is more and more evidence that a tumor infection by an oncolytic virus opens up a number of options for further immunomodulating interventions such as systemic chemotherapy, generic immunostimulating strategies, dendritic cell-based vaccines, and antigenic libraries to further support clinical efficacy of oncolytic virotherapy.

  20. Recombinant human leptin attenuates stress axis activity in common carp (Cyprinus carpio L.).

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    Gorissen, Marnix; Bernier, Nicholas J; Manuel, Remy; de Gelder, Stefan; Metz, Juriaan R; Huising, Mark O; Flik, Gert

    2012-08-01

    Proper functioning of the endocrine stress axis requires communication between the stress axis and other regulatory mechanisms. We here describe an intimate interplay between the stress axis and recombinant human leptin (rhLeptin) in a teleostean fish, the common carp Cyprinus carpio. Restraint stress (by netting up to 96h) increased plasma cortisol but did not affect hepatic leptin expression. Perifusion of pituitary glands or head kidneys with rhLeptin revealed direct effects of rhLeptin on both tissues. RhLeptin suppresses basal and CRF-induced ACTH-secretion in a rapid and concentration-dependent manner. The rhLeptin effect persisted for over an hour after administration had been terminated. RhLeptin decreases basal interrenal cortisol secretion in vitro, and by doing so attenuates ACTH-stimulated cortisol production; rhLeptin does not affect interrenal ACTH-sensitivity. Our findings show that the endocrine stress axis activity and leptin are inseparably linked in a teleostean fish, a notion relevant to further our insights in the evolution of leptin physiology in vertebrates.

  1. Recombinant interleukin-1 receptor antagonist attenuates the severity of chronic pancreatitis induced by TNBS in rats.

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    Xu, Chunfang; Shen, Jiaqing; Zhang, Jing; Jia, Zhenyu; He, Zhilong; Zhuang, Xiaohui; Xu, Ting; Shi, Yuqi; Zhu, Shunying; Wu, Mingyuan; Han, Wei

    2015-02-15

    Chronic pancreatitis (CP) is a common disease in the department of gastroenterology, with the main symptoms of exocrine and/or endocrine insufficiency and abdominal pain. The pathogenic mechanism of CP is still not fully clarified and the aims of treatment now are to relieve symptoms. In this study, we attempted to find a connection between interleukin-1β (IL-1β) and interleukin-1 receptor antagonist (IL-1Ra) in trinitrobenzene sulfonic acid (TNBS)-induced chronic pancreatitis, and then the therapeutic effect of recombinant IL-1Ra was also detected in the CP model. Chronic pancreatitis was induced by intraductal infusion of TNBS in SD rats followed by a consecutive administration of rIL-1Ra, and the histological changes and collagen content in the pancreas were measured, as well as the abdominal hypersensitivity. We found that rhIL-1Ra could attenuate the severity of chronic pancreatic injury, modulate the extracellular matrix secretion, focal proliferation and apoptosis, and cellular immunity in TNBS-induced CP. Interestingly, rIL-1Ra could also block the pancreatitis-induced referred abdominal hypersensitivity. In conclusion, IL-1Ra may play a protective role in CP and rIL-1Ra would be a potential therapeutic target for the treatment of CP, while its possible mechanisms and clinical usage still need further investigation.

  2. Oncolytic vaccinia therapy of squamous cell carcinoma

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    Yu Yong A

    2009-07-01

    Full Text Available Abstract Background Novel therapies are necessary to improve outcomes for patients with squamous cell carcinomas (SCC of the head and neck. Historically, vaccinia virus was administered widely to humans as a vaccine and led to the eradication of smallpox. We examined the therapeutic effects of an attenuated, replication-competent vaccinia virus (GLV-1h68 as an oncolytic agent against a panel of six human head and neck SCC cell lines. Results All six cell lines supported viral transgene expression (β-galactosidase, green fluorescent protein, and luciferase as early as 6 hours after viral exposure. Efficient transgene expression and viral replication (>150-fold titer increase over 72 hrs were observed in four of the cell lines. At a multiplicity of infection (MOI of 1, GLV-1h68 was highly cytotoxic to the four cell lines, resulting in ≥ 90% cytotoxicity over 6 days, and the remaining two cell lines exhibited >45% cytotoxicity. Even at a very low MOI of 0.01, three cell lines still demonstrated >60% cell death over 6 days. A single injection of GLV-1h68 (5 × 106 pfu intratumorally into MSKQLL2 xenografts in mice exhibited localized intratumoral luciferase activity peaking at days 2–4, with gradual resolution over 10 days and no evidence of spread to normal organs. Treated animals exhibited near-complete tumor regression over a 24-day period without any observed toxicity, while control animals demonstrated rapid tumor progression. Conclusion These results demonstrate significant oncolytic efficacy by an attenuated vaccinia virus for infecting and lysing head and neck SCC both in vitro and in vivo, and support its continued investigation in future clinical trials.

  3. Oncolytic virus therapy for cancer

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    Goldufsky J

    2013-09-01

    Full Text Available Joe Goldufsky,1 Shanthi Sivendran,3 Sara Harcharik,4 Michael Pan,4 Sebastian Bernardo,4 Richard H Stern,5 Philip Friedlander,4 Carl E Ruby,1,2 Yvonne Saenger,4 Howard L Kaufman1,2 Departments of 1Immunology & Microbiology and 2Surgery, Rush University Medical Center, Chicago IL, USA 3Hematology/Oncology Medical Specialists, Lancaster General Health, Lancaster, PA, USA, and Departments of 4Medical Oncology and 5Radiology, Tisch Cancer Institute, The Mount Sinai School of Medicine, New York, NY, USA Abstract: The use of oncolytic viruses to treat cancer is based on the selection of tropic tumor viruses or the generation of replication selective vectors that can either directly kill infected tumor cells or increase their susceptibility to cell death and apoptosis through additional exposure to radiation or chemotherapy. In addition, viral vectors can be modified to promote more potent tumor cell death, improve the toxicity profile, and/or generate host antitumor immunity. A variety of viruses have been developed as oncolytic therapeutics, including adenovirus, vaccinia virus, herpesvirus, coxsackie A virus, Newcastle disease virus, and reovirus. The clinical development of oncolytic viral therapy has accelerated in the last few years, with several vectors entering clinical trials for a variety of cancers. In this review, current strategies to optimize the therapeutic effectiveness and safety of the major oncolytic viruses are discussed, and a summary of current clinical trials is provided. Further investigation is needed to characterize better the clinical impact of oncolytic viruses, but there are increasing data demonstrating the potential promise of this approach for the treatment of human and animal cancers. Keywords: cancer, gene therapy, oncolytic therapy, virus, treatment

  4. Sulfonimidamide analogs of oncolytic sulfonylureas.

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    Toth, J E; Grindey, G B; Ehlhardt, W J; Ray, J E; Boder, G B; Bewley, J R; Klingerman, K K; Gates, S B; Rinzel, S M; Schultz, R M; Weir, L C; Worzalla, J F

    1997-03-14

    A series of sulfonimidamide analogs of the oncolytic diarylsulfonylureas was synthesized and evaluated for (1) in vitro cytotoxicity against CEM cells, (2) in vivo antitumor activity against subaxillary implanted 6C3HED lymphosarcoma, and (3) metabolic breakdown to the o-sulfate of p-chloroaniline. The separated enantiomers of one sulfonimidamide analog displayed very different activities in the in vivo screening model. In general, several analogs demonstrated excellent growth inhibitory activity in the 6C3HED model when dosed orally or intraperitoneally. A correlative structure-activity relationship to the oncolytic sulfonylureas was not apparent.

  5. Treatment with recombinant lubricin attenuates osteoarthritis by positive feedback loop between articular cartilage and subchondral bone in ovariectomized rats.

    Science.gov (United States)

    Cui, Zhuang; Xu, Changpeng; Li, Xue; Song, Jinqi; Yu, Bin

    2015-05-01

    Osteoarthritis (OA) is a most commonly multifactorial degenerative joint disease along with the aging population, particularly in postmenopausal women. During the onset of OA, articular cartilage and subchondral bone act in concert as a functional unit. This present study is to investigate the effects of early or late treatment with recombinant lubricin on the onset of osteoarthritis (OA) in ovariectomized (OVX) rats. We found that both early and late recombinant lubricin treatments attenuated the onset of OA by positive feedback loop between articular cartilage and subchondral bone, although late treatment contributed to a lesser effect compared with early treatment. Specifically, treatment with recombinant lubricin protected articular cartilage from degeneration, demonstrated by lower proteoglycan loss, lower OARSI scores, less calcification cartilage zone and reduced immunostaining for collagen X (Col X) and matrix metalloproteinase (MMP-13) but increased the expression of lubricin, in comparison with vehicle-treated OVX rat group. Further, chondroprotective effects of lubricin normalized bone remodeling in subchondral bone underneath. It's suggested that treatment with recombinant lubricin inhibited the elevation of TRAP and Osterix positive cells in OVX rats and led to the normalization of subchondral bone microarchitectures with the suppression of subsidence of bone volume ratio (BV/TV) and trabecular thickness (Tb.Th) and the increase of trabecular separation (Tb.Sp) in vehicle-treated OVX rats. What's more, the normalization of subchondral bone in turn attenuated the articular cartilage erosion by inhibiting vascular invasion from subchondral bone to calcified cartilage zone, exemplified by inhibiting the elevation of CD31 positive cells in calcified cartilage and angiography in subchondral bone. Together, these results shed light that both early and late recombinant lubricin treatments attenuate the onset of OA by balancing the interplay between articular

  6. Construction of recombinant attenuated Salmonella typhimurium DNA vaccine expressing H pylori ureB and IL-2

    Institute of Scientific and Technical Information of China (English)

    Can Xu; Zhao-Shen Li; Yi-Qi Du; Yan-Fang Gong; Hua Yang; Bo Sun; Jing Jin

    2007-01-01

    AIM: To construct a recombinant live attenuated Salmonella typhimurium DNA vaccine encoding H pylori ureB gene and mouse IL-2 gene and to detect its immunogenicity in vitro and in vivo.METHODS: H pylori ureB and mouse IL-2 gene fragments were amplified by potymerase chain reaction (PCR) and cloned into pUCmT vector. DNA sequence of the amplified ureB and IL-2 genes was assayed, then cloned into the eukaryotic expression vector pIRES through enzyme digestion and ligation reactions resulting in pIRES-ureB and pIRES-ureB-IL-2. The recombinant plasmids were used to transform competent E. Coli DH5a, and the positive clones were screened by PCR and restriction enzyme digestion. Then, the recombinant pIRES-ureB and pIRES-ureB-IL-2 were used to transform LB5000 and the recombinant plasmids extracted from LB5000 were finally introduced into the final host SL7207. After that, recombinant strains were grown in vitro repeatedly. In order to detect the immunogenicity of the vaccine in vitro, pIRES-ureB and pIRES-ureB-IL-2 were transfected to COS-7 cells using Lipofectamine TM 2000, the immunogenicity of expressed UreB and IL-2 proteins was assayed with SDS-PAGE and Western blot. C57BL/6 mice were orally immunized with 1 x 108 recombinant attenuated Salmonella typhimurium DNA vaccine. Four weeks after vaccination, mice were challenged with 1 x 107 CFU of live Hpylori SSI. Mice were sacrificed and the stomach was isolated for examination of H pylori 4 wk post-challenge.RESULTS: The 1700 base pair ureB gene fragment amplified from the genomic DNA was consistent with the sequence of H pylori ureB by sequence analysis. The amplified 510 base pair fragment was consistent with the sequence of mouse IL-2 in gene bank. It was confirmed by PCR and restriction enzyme digestion that H pylori ureB and mouse IL-2 genes were inserted into the eukaryotic expression vector pIRES. The experiments in vitro snowed that stable recombinant live attenuated Salmonella typhimurium DNA vaccine carrying

  7. Recombinant constructions and infectivity analysis of tobacco mosaic virus and attenuated tomato mosaic virus N14 genomes

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The recombinant clones of pTN and pNT have been constructed by exchanging the coding regions of the movement proteins (MP), coat proteins (CP) and 3′noncoding regions between the cDNAs of the tobacco mosaic virus (Chinese Isolate, TMV-Cv) and the attenuated tomato mosaic virus N14 genomes, and used as templates for in vitro runoff transcription. Their transcripts have been used for tobacco infection assays. The infection results show that the transcripts of pTN and pNT are infectious. Local lesions were observed in the leaves of Nicotiana tabacum cv. Samsun NN inoculated with pTN transcript, but were fewer than those in the same kind of plant induced by pTMV-Cv transcript. Systemic symptoms were also observed in N. tabacum cv. Huangmiaoyu induced by pTN transcript, but were slighter than those on the same kind of tobacco induced by pTMV-Cv transcript. Local lesions were shown in N. tabacum cv. Samsun NN inoculated with pNT transcript, but were more than those in the same kind of plant induced by pN14 transcript while no systemic symptom was displayed in N. tabacum cv. Huangmiaoyu. These results suggest that the recombinant viruses of TN and NT are able to propagate in the assayed tobaccos, and they keep the most same phenotypic character with pTMV-Cv and pN14 transcripts, and TMV-Cv and N14 as well. The conjunctions between the replicase and the MP, CP and 3′noncoding regions are not stringent. Apparently there is a compatible function complementation between the homologous subgenomes of TMV-Cv and N14. From those above it could be probably presumed that the mutagenized replicase gene of N14 plays a major role in contributing to the virus attenuation while its mutagenized MP gene could avianize the symptoms of the infected tobaccos.

  8. Immune responses to a recombinant attenuated Salmonella typhimurium strain expressing a Taenia solium oncosphere antigen TSOL18.

    Science.gov (United States)

    Ding, Juntao; Zheng, Yadong; Wang, Ying; Dou, Yongxi; Chen, Xiaoyu; Zhu, Xueliang; Wang, Shuai; Zhang, Shaohua; Liu, Zhenyong; Hou, Junling; Zhai, Junjun; Yan, Hongbin; Luo, Xuenong; Cai, Xuepeng

    2013-01-01

    A tapeworm, Taenia solium, remains a great threat to human health, particularly in developing countries. The life cycle of T. solium is thought to be terminated via vaccination of intermediate hosts. In this study, we constructed a recombinant attenuated Salmonella typhimurium live vaccine strain χ4558 expressing a TSOL18 antigen. SDS-PAGE and Western blot confirmed the expression of the interest protein and its antigenic property. The recombinant strain stably propagated in vitro, of which the growth was not reversely influenced by TSOL18 protein expressed. It was also shown that mice survived 10(12) CFU of S. typhimurium χ4558, while all mice infected with 10(7) CFU of the wild-type died within five days. The mouse experiment indicated that vaccine strain χ4558 induced a high titer of specific antibody for a long time. In contrast to the controls, the vaccinated mice had an obvious augment of CD4(+) and CD8(+) T lymphocytes and the percentage of helper CD4(+)/CD8(+) T lymphocytes was significantly increased (psolium.

  9. Safety, tolerability, and immunogenicity of a recombinant, genetically engineered, live-attenuated vaccine against canine blastomycosis.

    Science.gov (United States)

    Wüthrich, Marcel; Krajaejun, Theerapong; Shearn-Bochsler, Valerie; Bass, Chris; Filutowicz, Hanna I; Legendre, Alfred M; Klein, Bruce S

    2011-05-01

    Blastomycosis is a severe, commonly fatal infection caused by the dimorphic fungus Blastomyces dermatitidis in dogs that live in the United States, Canada, and parts of Africa. The cost of treating an infection can be expensive, and no vaccine against this infection is commercially available. A genetically engineered live-attenuated strain of B. dermatitidis lacking the major virulence factor BAD-1 successfully vaccinates against lethal experimental infection in mice. Here we studied the safety, toxicity, and immunogenicity of this strain as a vaccine in dogs, using 25 beagles at a teaching laboratory and 78 foxhounds in a field trial. In the beagles, escalating doses of live vaccine ranging from 2 × 10⁴ to 2 × 10⁷ yeast cells given subcutaneously were safe and did not disseminate to the lung or induce systemic illness, but a dose of vaccine dose of 10⁵ yeast cells was also well tolerated in vaccinated foxhounds who had never had blastomycosis; however, vaccinated dogs with prior infection had more local reactions at the vaccine site. The draining lymph node cells and peripheral blood lymphocytes from vaccinated dogs demonstrated gamma interferon (IFN-γ), tumor necrosis factor alpha (TNF-α), and granulocyte-macrophage colony-stimulating factor (GM-CSF) specifically in response to stimulation with Blastomyces antigens. Thus, the live-attenuated vaccine against blastomycosis studied here proved safe, well tolerated, and immunogenic in dogs and merits further studies of vaccine efficacy.

  10. Oncolytic Newcastle Disease Virus as treatment for pancreatic cancer

    NARCIS (Netherlands)

    P.R.A. Buijs (Pascal)

    2015-01-01

    markdownabstractAbstract In this thesis, experiments are presented that were undertaken to develop oncolytic NDV for the treatment of pancreatic adenocarcinoma. Oncolytic viruses (OVs), reported first halfway the previous century, have undergone a tremendous evolution from anecdotal experimental an

  11. Evaluation of attenuated Salmonella choleraesuis-mediated inhibin recombinant DNA vaccine in rats.

    Science.gov (United States)

    Hui, F M; Meng, C L; Guo, N N; Yang, L G; Shi, F X; Mao, D G

    2014-08-07

    DNA vaccination has been studied intensively as a potential vaccine technology. We evaluated the effect of an attenuated Salmonella choleraesuis-mediated inhibin DNA vaccine in rats. First, 15 rats were treated with different doses of an inhibin vaccine to evaluate vaccine safety. Next, 30 rats were divided into 3 groups and injected intramuscularly with the inhibin vaccine two (T1) or three times (T2) or with control bacteria (Con) at 4-week intervals. The inhibin antibody levels increased [positive/negative well (P/N) value: T1 vs Con = 2.39 ± 0.01 vs 1.08 ± 0.1; T2 vs Con = 2.36 ± 0.1 vs 1.08 ± 0.1, P < 0.05] at week 2 and were maintained at a high level in T1 and T2 until week 8, although a small decrease in T2 was observed at week 10. Rats in the T1 group showed more corpora lutea compared with the Con group (10.50 ± 0.87 vs 7.4 ± 0.51, P < 0.05). Estradiol (0.439 ± 0.052 vs 0.719 ± 0.063 ng/mL, P < 0.05) and progesterone (1.315 ± 0.2 vs 0.737 ± 0.11 ng/mL, P < 0.05) levels differed significantly at metestrus after week 10 between rats in the T1 and Con groups. However, there were no significant differences in body, ovary, uterus weights, or pathological signs in the ovaries after immunization, indicating that this vaccine is safe. In conclusion, the attenuated S. choleraesuis-mediated inhibin vaccine may be an alternative to naked inhibin plasmids for stimulating ovarian follicular development to increase the ovulation rate in rats.

  12. Recombinant adeno-associated virus-mediated delivery of antisense angiotensin Ⅱ receptor 1 gene attenuates hypertension development

    Institute of Scientific and Technical Information of China (English)

    Xu-guang LI; Jiang-tao YAN; Xi-zheng XU; Jia-ning WANG; Li-ming CHENG; Tao WANG; Ping ZUO; Dao-wen WANG

    2007-01-01

    Aim:The renin-angiotensin system plays a crucial role in the development and establishment of hypertension,and the pharmacological blockade of the system results in a reduction in blood pressure. In the present study,we investigated whether the effects of a novel,double-stranded,recombinant adeno-associated virus vector (rAAV)-mediated antisense angiotensin Ⅱ receptor l (AT1R) gene efficiently prevents the development of hypertension induced by a high-salt diet in adult,male Sprague-Dawley (SD) rats. Methods:A rAAV was prepared with a cassette containing a cytomegalovirus promoter and partial cDNA (660 base pairs) for the AT1R inserted in the antisense direction (rAAV-AT1AS). A single tail vein injection of the rAAV-AT1-AS or rAAV-GFP (green fluorescent protein,a reporter gene) was performed in adult,male SD rats. Two weeks after injection,the animals were fed a diet containing 8% NaCI,and the systolic blood pressure was measured weekly using the tail-cuff method for 12 weeks. Results:The high-salt diet induced a significant rise in systolic blood pressure in the rAAV-GFP-treated animals;however,the rAAV-AT:AS treatment attenuated the rise in blood pressure (142.7±4.5 mmHg vs 117±3.8 mmHg,P<0.01),and the hypotensive effect was maintained until the experiments ended at 12 weeks. In the rAAV-GFP-treated animals AT1 was overexpressed in various tissues,especially in the aorta and kidney at mRNA levels;in contrast,rAAV-AT:AS treatment markedly attenuated AT1 expression. Furthermore,rAAV-AT:AS treatment prevented target organ damages from hypertension,including cardiac dysfunction and renal injury compared to the rAAV-GFP group. Conclusion:These results suggest that rAAVmediated anti-AT1 delivery attenuates the development of hypertension and protects against renal injury and cardiac remodeling.

  13. Oncolytic myxoma virus: the path to clinic.

    Science.gov (United States)

    Chan, Winnie M; Rahman, Masmudur M; McFadden, Grant

    2013-09-06

    Many common neoplasms are still noncurative with current standards of cancer therapy. More therapeutic modalities need to be developed to significantly prolong the lives of patients and eventually cure a wider spectrum of cancers. Oncolytic virotherapy is one of the promising new additions to clinical cancer therapeutics. Successful oncolytic virotherapy in the clinic will be those strategies that best combine tumor cell oncolysis with enhanced immune responses against tumor antigens. The current candidate oncolytic viruses all share the common property that they are relatively nonpathogenic to humans, yet they have the ability to replicate selectively in human cancer cells and induce cancer regression by direct oncolysis and/or induction of improved anti-tumor immune responses. Many candidate oncolytic viruses are in various stages of clinical and preclinical development. One such preclinical candidate is myxoma virus (MYXV), a member of the Poxviridae family that, in its natural setting, exhibits a very restricted host range and is only pathogenic to European rabbits. Despite its narrow host range in nature, MYXV has been shown to productively infect various classes of human cancer cells. Several preclinical in vivo modeling studies have demonstrated that MYXV is an attractive and safe candidate oncolytic virus, and hence, MYXV is currently being developed as a potential therapeutic for several cancers, such as pancreatic cancer, glioblastoma, ovarian cancer, melanoma, and hematologic malignancies. This review highlights the preclinical cancer models that have shown the most promise for translation of MYXV into human clinical trials.

  14. Systemic treatment of xenografts with vaccinia virus GLV-1h68 reveals the immunologic facet of oncolytic therapy

    Directory of Open Access Journals (Sweden)

    Liu Hui

    2009-07-01

    Full Text Available Abstract Background GLV-1h68 is an attenuated recombinant vaccinia virus (VACV that selectively colonizes established human xenografts inducing their complete regression. Results Here, we explored xenograft/VACV/host interactions in vivo adopting organism-specific expression arrays and tumor cell/VACV in vitro comparing VACV replication patterns. There were no clear-cut differences in vitro among responding and non-responding tumors, however, tumor rejection was associated in vivo with activation of interferon-stimulated genes (ISGs and innate immune host's effector functions (IEFs correlating with VACV colonization of the xenografts. These signatures precisely reproduce those observed in humans during immune-mediated tissue-specific destruction (TSD that causes tumor or allograft rejection, autoimmunity or clearance of pathogens. We recently defined these common pathways in the "immunologic constant of rejection" hypothesis (ICR. Conclusion This study provides the first prospective validation of a universal mechanism associated with TSD. Thus, xenograft infection by oncolytic VACV, beyond offering a promising therapy of established cancers, may represent a reliable pre-clinical model to test therapeutic strategies aimed at modulating the central pathways leading to TSD; this information may lead to the identification of principles that could refine the treatment of cancer and chronic infection by immune stimulation or autoimmunity and allograft rejection through immune tolerance.

  15. Immunogenicity of recombinant attenuated Salmonella enterica serovar Typhimurium vaccine strains carrying a gene that encodes Eimeria tenella antigen SO7.

    Science.gov (United States)

    Konjufca, Vjollca; Jenkins, Mark; Wang, Shifeng; Juarez-Rodriguez, Maria Dolores; Curtiss, Roy

    2008-12-01

    Recombinant attenuated Salmonella vaccines against avian coccidiosis were developed to deliver Eimeria species antigens to the lymphoid tissues of chickens via the type 3 secretion system (T3SS) and the type 2 secretion system (T2SS) of Salmonella. For antigen delivery via the T3SS, the Eimeria tenella gene encoding sporozoite antigen SO7 was cloned downstream of the translocation domain of the Salmonella enterica serovar Typhimurium sopE gene in the parental pYA3868 and pYA3870 vectors to generate pYA4156 and pYA4157. Newly constructed T3SS vectors were introduced into host strain chi8879 (Delta phoP233 Delta sptP1033::xylE Delta asdA16), an attenuated derivative of the highly virulent UK-1 strain. The SopE-SO7 fusion protein was secreted by the T3SS of Salmonella. The vector pYA4184 was constructed for delivery of the SO7 antigen via the T2SS. The SO7 protein was toxic to Salmonella when larger amounts were synthesized; thus, the synthesis of this protein was placed under the control of the lacI repressor gene, whose expression in turn was dependent on the amount of available arabinose in the medium. The pYA4184 vector was introduced into host strain chi9242 (Delta phoP233 Delta asdA16 Delta araBAD23 Delta relA198::araC P(BAD) lacI TT [TT is the T4ipIII transcription terminator]). In addition to SO7, for immunization and challenge studies we used the EAMZ250 antigen of Eimeria acervulina, which was previously shown to confer partial protection against E. acervulina challenge when it was delivered via the T3SS. Immunization of chickens with a combination of the SO7 and EAMZ250 antigens delivered via the T3SS induced superior protection against challenge by E. acervulina. In contrast, chickens immunized with SO7 that was delivered via the T2SS of Salmonella were better protected from challenge by E. tenella.

  16. Oncolytic Virotherapy for Hematological Malignancies

    Directory of Open Access Journals (Sweden)

    Swarna Bais

    2012-01-01

    Full Text Available Hematological malignancies such as leukemias, lymphomas, multiple myeloma (MM, and the myelodysplastic syndromes (MDSs primarily affect adults and are difficult to treat. For high-risk disease, hematopoietic stem cell transplant (HCT can be used. However, in the setting of autologous HCT, relapse due to contamination of the autograft with cancer cells remains a major challenge. Ex vivo manipulations of the autograft to purge cancer cells using chemotherapies and toxins have been attempted. Because these past strategies lack specificity for malignant cells and often impair the normal hematopoietic stem and progenitor cells, prior efforts to ex vivo purge autografts have resulted in prolonged cytopenias and graft failure. The ideal ex vivo purging agent would selectively target the contaminating cancer cells while spare normal stem and progenitor cells and would be applied quickly without toxicities to the recipient. One agent which meets these criteria is oncolytic viruses. This paper details experimental progress with reovirus, myxoma virus, measles virus, vesicular stomatitis virus, coxsackievirus, and vaccinia virus as well as requirements for translation of these results to the clinic.

  17. Attenuation of skeletal muscle wasting with recombinant human growth hormone secreted from a tissue-engineered bioartificial muscle

    Science.gov (United States)

    Vandenburgh, H.; Del Tatto, M.; Shansky, J.; Goldstein, L.; Russell, K.; Genes, N.; Chromiak, J.; Yamada, S.

    1998-01-01

    Skeletal muscle wasting is a significant problem in elderly and debilitated patients. Growth hormone (GH) is an anabolic growth factor for skeletal muscle but is difficult to deliver in a therapeutic manner by injection owing to its in vivo instability. A novel method is presented for the sustained secretion of recombinant human GH (rhGH) from genetically modified skeletal muscle implants, which reduces host muscle wasting. Proliferating murine C2C12 skeletal myoblasts stably transduced with the rhGH gene were tissue engineered in vitro into bioartificial muscles (C2-BAMs) containing organized postmitotic myofibers secreting 3-5 microg of rhGH/day in vitro. When implanted subcutaneously into syngeneic mice, C2-BAMs delivered a sustained physiologic dose of 2.5 to 11.3 ng of rhGH per milliliter of serum. rhGH synthesized and secreted by the myofibers was in the 22-kDa monomeric form and was biologically active, based on downregulation of a GH-sensitive protein synthesized in the liver. Skeletal muscle disuse atrophy was induced in mice by hindlimb unloading, causing the fast plantaris and slow soleus muscles to atrophy by 21 to 35% ( < 0.02). This atrophy was significantly attenuated 41 to 55% (p < 0.02) in animals that received C2-BAM implants, but not in animals receiving daily injections of purified rhGH (1 mg/kg/day). These data support the concept that delivery of rhGH from BAMs may be efficacious in treating muscle-wasting disorders.

  18. Increasing the Efficacy of Oncolytic Adenovirus Vectors

    Directory of Open Access Journals (Sweden)

    William S. M. Wold

    2010-08-01

    Full Text Available Oncolytic adenovirus (Ad vectors present a new modality to treat cancer. These vectors attack tumors via replicating in and killing cancer cells. Upon completion of the vector replication cycle, the infected tumor cell lyses and releases progeny virions that are capable of infecting neighboring tumor cells. Repeated cycles of vector replication and cell lysis can destroy the tumor. Numerous Ad vectors have been generated and tested, some of them reaching human clinical trials. In 2005, the first oncolytic Ad was approved for the treatment of head-and-neck cancer by the Chinese FDA. Oncolytic Ads have been proven to be safe, with no serious adverse effects reported even when high doses of the vector were injected intravenously. The vectors demonstrated modest anti-tumor effect when applied as a single agent; their efficacy improved when they were combined with another modality. The efficacy of oncolytic Ads can be improved using various approaches, including vector design, delivery techniques, and ancillary treatment, which will be discussed in this review.

  19. Development of prophylactic recombinant HPV58-attenuated Shigeila live vector vaccine and evaluation of its protective efficacy and immunogenicity in the guinea pig keratoconjunctivitis model

    Institute of Scientific and Technical Information of China (English)

    Wensheng Li; Hongli Liu; Xiaofeng Yang; Jin Zheng; Yili Wang; Lusheng Si

    2009-01-01

    To develop a prophylactic recombinant HPV58L1-attenuated Shigella live vector vaccine and evaluate its protective efficacy and immunogenicity in the guinea pig keratoconjunctivitis model, the HPV58L1 gene was cloned into vector pUCmt, and then subcloned into the suicide vector pCVD442. The recombinant plasmid pCVD442-HPV58L1 was introduced into attenuated Shigella (sf301:△virG) with the helper plasmid PRK2013 by filter mating. The positive colonies were harvested and confirmed by polymerase chain reaction. The expression of the HPV58L1 protein with a molecu-lar weight of 60 kDa was confirmed by western blot. The ability of the interested protein to self-assemble into virus-like particles was identified by transmission electron microscope, and murine erythrocyte hemagglu-tination assay. The guinea pig keratoconjunctivitis model was used to evaluate the protective efficacy and immunogenicity of the vaccine. Animal experiments showed that there was no keratoconjunctivitis occurred in the immunized group (HPV58-attenuated Shigella), and the serum levels of anti-HPV58L1-IgG and -IgA were obviously increased (P0.05). Enzyme-linked immunosorbent spot assay showed that HPV58L1-specific IgA-antibody-secreting cells (ASC) and IgG-ASC of spleen and lymph nodes were also obviously increased (P<0.01). In this study, a recombi-nant HPV58L1-attenuated Shigella live vector vaccine was successfully constructed, and it could induce strong humoral immune responses in the immunized animals, and induce protective antibody production.

  20. Successful cross-protective efficacy induced by heat-adapted live attenuated nephropathogenic infectious bronchitis virus derived from a natural recombinant strain.

    Science.gov (United States)

    Lim, Tae-Hyun; Youn, Ha-Na; Yuk, Seong-Su; Kwon, Jung-Hoon; Hong, Woo-Tack; Gwon, Gyeong-Bin; Lee, Jung-Ah; Lee, Joong-Bok; Lee, Sang-Won; Song, Chang-Seon

    2015-12-16

    A natural recombinant nephropathogenic K40/09 strain of infectious bronchitis virus (IBV) was heat-adapted for possible future use as live attenuated vaccine. The K40/09 strain was selected during successive serial passages in specific-pathogen free (SPF) embryonated eggs at sub-optimal higher temperature (56°C). Unlike the parental strain, the attenuated strain, designated K40/09 HP50, was found to be safe in 1-day-old SPF chicks, which showed neither mortality nor signs of morbidity, and rarely induced ciliostasis or histological changes in the trachea and kidney after intraocular and fine-spray administration. K40/09 HP50 provided almost complete protection against two distinct subgroups of a nephropathogenic strain (KM91-like and QX-like subgroup) and elicited the production of high titers of neutralizing antibody (neutralization index of 3.6). We conclude that the K40/09 HP50 vaccine virus is rapidly attenuated by heat adaptation and exhibits the desired level of attenuation, immunogenicity, and protective efficacy required for a live attenuated vaccine. These results indicate that the K40/09 vaccine could be helpful for the reduction of economic losses caused by recently emergent nephropathogenic IBV infection in many countries.

  1. Safety Overview of a Recombinant Live-Attenuated Tetravalent Dengue Vaccine: Pooled Analysis of Data from 18 Clinical Trials.

    Directory of Open Access Journals (Sweden)

    Sophia Gailhardou

    2016-07-01

    Full Text Available A recombinant live attenuated tetravalent dengue vaccine (CYD-TDV has been shown to be efficacious in preventing virologically-confirmed dengue disease, severe dengue disease and dengue hospitalization in children aged 2-16 years in Asia and Latin America. We analyzed pooled safety data from 18 phase I, II and III clinical trials in which the dengue vaccine was administered to participants aged 2-60 years, including long-term safety follow-up in three efficacy trials. The participants were analyzed according to their age at enrollment. The percentage of participants aged 2-60 years reporting ≥1 solicited injection-site or systemic reactions was slightly higher in the CYD-TDV group than in the placebo group. The most common solicited injection-site reactions were pain. Headache and malaise were the most common solicited systemic reactions. In both groups 0.3% of participants discontinued for safety reasons. The most common unsolicited adverse events were injection-site reactions, gastrointestinal disorders, and infections. Reactogenicity did not increase with successive doses of CYD-TDV. The frequency and nature of SAEs occurring within 28 days of any dose were similar in the CYD-TDV and placebo groups and were common medical conditions that could be expected as a function of age. Baseline dengue virus serostatus did not appear to influence the safety profile. No vaccine-related anaphylactic reactions, neurotropic events or viscerotropic events were reported. In year 3 after dose 1, an imbalance for dengue hospitalization, including for severe dengue, observed in participants aged <9 years in the CYD-TDV group compared with the placebo group was not observed for participants aged ≥9 years. In Year 4, this imbalance in participants aged <9 years was less marked, giving an overall lower risk of dengue hospitalization or severe dengue from dose 1 to Year 4 in the CYD-TDV group. These results have contributed to the definition of the target

  2. Safety Overview of a Recombinant Live-Attenuated Tetravalent Dengue Vaccine: Pooled Analysis of Data from 18 Clinical Trials

    Science.gov (United States)

    Gailhardou, Sophia; Skipetrova, Anna; Dayan, Gustavo H.; Jezorwski, John; Saville, Melanie; Van der Vliet, Diane; Wartel, T. Anh

    2016-01-01

    A recombinant live attenuated tetravalent dengue vaccine (CYD-TDV) has been shown to be efficacious in preventing virologically-confirmed dengue disease, severe dengue disease and dengue hospitalization in children aged 2–16 years in Asia and Latin America. We analyzed pooled safety data from 18 phase I, II and III clinical trials in which the dengue vaccine was administered to participants aged 2–60 years, including long-term safety follow-up in three efficacy trials. The participants were analyzed according to their age at enrollment. The percentage of participants aged 2–60 years reporting ≥1 solicited injection-site or systemic reactions was slightly higher in the CYD-TDV group than in the placebo group. The most common solicited injection-site reactions were pain. Headache and malaise were the most common solicited systemic reactions. In both groups 0.3% of participants discontinued for safety reasons. The most common unsolicited adverse events were injection-site reactions, gastrointestinal disorders, and infections. Reactogenicity did not increase with successive doses of CYD-TDV. The frequency and nature of SAEs occurring within 28 days of any dose were similar in the CYD-TDV and placebo groups and were common medical conditions that could be expected as a function of age. Baseline dengue virus serostatus did not appear to influence the safety profile. No vaccine-related anaphylactic reactions, neurotropic events or viscerotropic events were reported. In year 3 after dose 1, an imbalance for dengue hospitalization, including for severe dengue, observed in participants aged dengue hospitalization or severe dengue from dose 1 to Year 4 in the CYD-TDV group. These results have contributed to the definition of the target population for vaccination (≥9 years old) for which CYD-TDV has a satisfactory safety profile. Long-term safety will continue to be monitored in the ongoing follow-up of efficacy trials. Safety and effectiveness in real-life settings

  3. Oncolytic and immunologic cancer therapy with GM-CSF-armed vaccinia virus of Tian Tan strain Guang9.

    Science.gov (United States)

    Deng, Lili; Fan, Jun; Guo, Mingming; Huang, Biao

    2016-03-28

    Targeted oncolytic vaccinia viruses are being developed as a novel strategy in cancer therapy. Arming vaccinia viruses with immunostimulatory cytokines can enhance antitumor efficacy. Such engineered oncolytic viruses, like JX-594, a Wyeth strain vaccinia virus modified with human granulocyte-macrophage colony-stimulating factor (GM-CSF), have shown promising results and have proceeded rapidly in clinical trials. However, the oncolytic potential of the Chinese vaccine strain Tian Tan (VTT) has not been explored. In this study, we constructed a targeted oncolytic vaccinia virus of Tian Tan strain Guang9 (VG9) expressing murine GM-CSF (VG9-GMCSF) and evaluated the antitumor effect of this recombinant vaccinia virus in a murine melanoma model. In vitro, viral replication and cytotoxicity of VG9-GMCSF was as potent as VG9; in vivo, VG9-GMCSF significantly inhibited the growth of subcutaneously implanted melanoma tumors, prolonged the survival of tumor-bearing mice, and produced an antitumor cytotoxic response. Such antitumor effect may be due to the lytic nature of virus as well as the stimulation of immune activity by GM-CSF production. Our results indicate that VG9-GMCSF induces strong tumoricidal activity, providing a potential therapeutic strategy for combating cancer.

  4. A bovine herpesvirus 5 recombinant defective in the thymidine kinase (TK gene and a double mutant lacking TK and the glycoprotein E gene are fully attenuated for rabbits

    Directory of Open Access Journals (Sweden)

    S.C. Silva

    2010-02-01

    Full Text Available Bovine herpesvirus 5 (BoHV-5, the agent of herpetic meningoencephalitis in cattle, is an important pathogen of cattle in South America and several efforts have been made to produce safer and more effective vaccines. In the present study, we investigated in rabbits the virulence of three recombinant viruses constructed from a neurovirulent Brazilian BoHV-5 strain (SV507/99. The recombinants are defective in glycoprotein E (BoHV-5gEΔ, thymidine kinase (BoHV-5TKΔ and both proteins (BoHV-5gEΔTKΔ. Rabbits inoculated with the parental virus (N = 8 developed neurological disease and died or were euthanized in extremis between days 7 and 13 post-infection (pi. Infectivity was detected in several areas of their brains. Three of 8 rabbits inoculated with the recombinant BoHV-5gEΔ developed neurological signs between days 10 and 15 pi and were also euthanized. A more restricted virus distribution was detected in the brain of these animals. Rabbits inoculated with the recombinants BoHV-5TKΔ (N = 8 or BoHV-5gEΔTKΔ (N = 8 remained healthy throughout the experiment in spite of variable levels of virus replication in the nose. Dexamethasone (Dx administration to rabbits inoculated with the three recombinants at day 42 pi did not result in viral reactivation, as demonstrated by absence of virus shedding and/or increase in virus neutralizing titers. Nevertheless, viral DNA was detected in the trigeminal ganglia or olfactory bulbs of all animals at day 28 post-Dx, demonstrating they were latently infected. These results show that recombinants BoHV-5TKΔ and BoHV-5gEΔTKΔ are attenuated for rabbits and constitute potential vaccine candidates upon the confirmation of this phenotype in cattle.

  5. Compact, accurate description of diagnostic neutral beam propagation and attenuation in a high temperature plasma for charge exchange recombination spectroscopy analysis.

    Science.gov (United States)

    Bespamyatnov, Igor O; Rowan, William L; Granetz, Robert S

    2008-10-01

    Charge exchange recombination spectroscopy on Alcator C-Mod relies on the use of the diagnostic neutral beam injector as a source of neutral particles which penetrate deep into the plasma. It employs the emission resulting from the interaction of the beam atoms with fully ionized impurity ions. To interpret the emission from a given point in the plasma as the density of emitting impurity ions, the density of beam atoms must be known. Here, an analysis of beam propagation is described which yields the beam density profile throughout the beam trajectory from the neutral beam injector to the core of the plasma. The analysis includes the effects of beam formation, attenuation in the neutral gas surrounding the plasma, and attenuation in the plasma. In the course of this work, a numerical simulation and an analytical approximation for beam divergence are developed. The description is made sufficiently compact to yield accurate results in a time consistent with between-shot analysis.

  6. Viral Oncolytic Therapeutics for Neoplastic Meningitis

    Science.gov (United States)

    2014-09-01

    the rat model. The therapeutic effect of HSV-1 oncolysis on meningeal metastases was presented ( oral ) at the annual meeting of the World Molecular...Abstracts, and Presentations Presentations & Abstracts: 1. Oral Presentation at WMIC, Seoul. “Novel oncolytic HSV-1 therapeutics for breast cancer...tomography of herpes simplex virus 1 oncolysis. Cancer Research. 2007; 67(7): 3295. 3. Kuruppu D, Tanabe KK. Viral oncolysis by herpes simplex virus and

  7. Immunotherapeutic Potential of Oncolytic Vaccinia Virus

    Directory of Open Access Journals (Sweden)

    Stephen eThorne

    2014-06-01

    Full Text Available The concept of oncolytic viral therapy was based on the hypothesis that engineering tumor-selectivity into the replication potential of viruses would permit direct destruction of tumor cells as a result of viral-mediated lysis, resulting in amplification of the therapy exclusively within the tumor environment. The immune response raised by the virus was considered to be necessary for the safety of the approach, but also something of a hindrance to optimal therapeutic activity and repeat dosing. However the pre-clinical and subsequent clinical success of several oncolytic viruses expressing selected cytokines has demonstrated the potential for harnessing the immune response as an additional and beneficial mechanism of therapeutic activity within the platform. Over the last few years a variety of novel approaches have been incorporated to try to enhance this immunotherapeutic activity. Several innovative and subtle approaches have moved far beyond the expression of a single cytokine transgene, with the hope of optimizing anti-tumor immunity while having minimal detrimental impact on viral oncolytic activity.

  8. Oncolytic virotherapy: the questions and the promise

    Directory of Open Access Journals (Sweden)

    Aurelian L

    2013-06-01

    Full Text Available Laure Aurelian Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD, USA Abstract: Oncolytic virotherapy is a new strategy to reduce tumor burden through selective virus replication in rapidly proliferating cells. Oncolytic viruses are members of at least ten virus families, each with its advantages and disadvantages. Here, I briefly review the recent advances and key challenges, as exemplified by the best-studied platforms. Recent advances include preclinical proof of feasibility, clinical evidence of tolerability and effectiveness, and the development of new strategies to improve efficacy. These include engineered tumor selectivity and expression of antitumorigenic genes that could function independently of virus replication, identification of combinatorial therapies that accelerate intratumoral virus propagation, and modification of immune responses and vascular delivery for treatment of metastatic disease. Key challenges are to select “winners” from the distinct oncolytic platforms that can stimulate anti-cancer immunity without affecting virus replication and can lyse cancer stem cells, which are most likely responsible for tumor maintenance, aggressiveness, and recurrence. Preventing the emergence of resistant tumor cells during virotherapy through the activation of multiple death pathways, the development of a better understanding of the mechanisms of cancer stem-cell lysis, and the development of more meaningful preclinical animal models are additional challenges for the next-generation of engineered viruses. Keywords: tumor cell lysis, virus replication, tumor selectivity, programmed cell death, immune response

  9. Oncolytic viruses: a step into cancer immunotherapy

    Directory of Open Access Journals (Sweden)

    Pol JG

    2011-12-01

    Full Text Available Jonathan G Pol, Julien Rességuier, Brian D LichtyMcMaster Immunology Research Centre, Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, CanadaAbstract: Oncolytic virotherapy is currently under investigation in phase I–III clinical trials for approval as a new cancer treatment. Oncolytic viruses (OVs selectively infect, replicate in, and kill tumor cells. For a long time, the therapeutic efficacy was thought to depend on the direct viral oncolysis (virocentric view. The host immune system was considered as a brake that impaired virus delivery and spread. Attention was paid primarily to approaches enhancing virus tumor selectivity and cytotoxicity and/or that limited antiviral responses. Thinking has changed over the past few years with the discovery that OV therapy was also inducing indirect oncolysis mechanisms. Among them, induction of an antitumor immunity following OV injection appeared to be a key factor for an efficient therapeutic activity (immunocentric view. Indeed, tumor-specific immune cells persist post-therapy and can search and destroy any tumor cells that escape the OVs, and thus immune memory may prevent relapse of the disease. Various strategies, which are summarized in this manuscript, have been developed to enhance the efficacy of OV therapy with a focus on its immunotherapeutic aspects. These include genetic engineering and combination with existing cancer treatments. Several are currently being evaluated in human patients and already display promising efficacy.Keywords: oncolytic virus, cancer immunotherapy, tumor antigen, cancer vaccine, combination strategies

  10. 特异性溶瘤重组腺病毒KH901的碘标记方法及其生物学分布%Iodination Conditions of KH901, a Tumor-specific Oncolytic Recombinant Adenovirus, and Its ~(125)I-labeled Compounds Biodistribution in Animals

    Institute of Scientific and Technical Information of China (English)

    米彦霞; 李云春; 龙亚红; 解朋

    2009-01-01

    研究一种~(125)I直接标记特异性溶瘤重组腺病毒KH901的简便高效的方法,以及评价~(125)I-KH901的体内生物学行为.采用N-溴代琥珀酰亚胺(NBS)方法对KH901进行标记,确定最佳标记条件;用凝胶过滤层析法对标记物进行分离纯化,纸层析法测定放化纯度.对~(125)I-KH901进行正常小鼠体内生物学分布检测.结果显示,~(125)I-KH901的放化纯达到95%以上,标记率可达到78%;正常小鼠尾静脉注射~(125)I-KH901后体内分布显示肝脏中放射性浓集度最高,24 h检测肝脏仍有较多放射性滞留,可达13.34 %ID/g,标记物在肾脏的摄取也较高,为8.06% ID/g. 因此, N-溴代琥珀酰亚胺(NBS)方法是一种步骤简便、标记率高的比较理想的碘标记病毒方法,~(125)I-KH901主要分布在肝脏和肾脏.%In this research was developed high efficiency method using ~(125)I for directly labeling KH901,a tumor-specific oncolytic recombinant adenovirus,biodistribution of ~(125)I-labeled compound in normal mice was investigated. ~(125)I-KH901 was prepared by N-bromosuccinimide labeling method to find the optimal ratio of labeling response. The compounds were isolated and purified by Sephadex-G10 agarose and the radiochemical purity of compounds was analyzed by paper chromatography. The radioactivity biodistribution in mice was measured at different times after caudal vein injection with 0.1ml ~(125)I-KH901. The labeling yield of ~(125)I-KH901 was 78% and the radiochemical purity was 95% after purification by Sephadex-G10 agarose. Biodistribution revealed that the uptake of ~(125)I-KH901 in liver was higher than in other organs at all time points of the experiment. ~(125)I-KH901 was mainly concentrated in liver,kidneys,spleen and lung. It can be seen that N-bromosuccinimide labeling method is an optimal method with simple steps and high labeling yield in labeling KH901 with ~(125)I. ~(125)I-KH901 has a biodistribution trait which is an advantage to treating liver

  11. 携带p53基因的重组1型单纯疱疹病毒溶瘤特性的实验观察%Oncolytic property of HSV-1 recombinant viruses carrying the p53 gene

    Institute of Scientific and Technical Information of China (English)

    王雪莹; 朱慧; 汪习; 刘晓娟; 马正海

    2016-01-01

    Objective To obtain the recombinant herpes simplex virus 1 (HSV-1) inserted p53 gene with homologous recombination technology and investigate the virus' replication ability and oncolytic property in vitro and in vivo.Methods A eukaryotic expression case with p53 gene was cloned into pKOS/BN.The pKOS/p53 was constructed and transfected to the E.coli with pHSV△IR-BAC by electroporation.Then the recombinant pHSV△IR-BAC/p53 was obtained and transfected into Vero cells.Recombinant virus (MH1004) was identified by Southern blot and Western blot.Then the virus' replication abilities in several human tumors cells were tested by plaque assay.A murine melanoma model was established by subcutaneous inoculation of B16 cells.A dosage of 2 × 106 PFU (plaque forming unit) of MH1004,MH1001,HSV-1 wt or PBS was injected 3 times intratumorally in every 3 days.The tumor volume and survival rate were measured twice a week.Results The results of Western blot showed that the p53 protein can be detected from the Vero cells infected by MH1004.The replication abilities of MH1004 and HSV-1 wt in the same tumor cell was insignificant (P > 0.05).And MH1004's replication abilities in SK-N-SH and U251 was significantly higher than other cancer cells.The tumors volume of group HSV-1 wt,MH1001 (HSV△IR) and MH1004 were (6 180 ±751),(5 760 ±267) and (4 850 ±532) mm3 compared with PBS group (9 860 ± 91) mm3,the difference of reduction of tumors volume was significant (P < 0.01).And the tumors volume of MH1004 group was smaller than HSV-1 wt and MH1001 group,but without significant difference (P > 0.05).And the survival rate of MH1004 treated mice (5/6) was greatly higher than PBS (3/6),HSV-1 wt (3/6) and MH1001 (3/6).Conclusion The replication abilities of MH1004 in neural tumor are very high and MH1004 can inhibit the growth of tumor so that prolong the survival of mice bearing mnurine melanoma.%目的 利用同源重组技术获得插入p53基因的重组1

  12. Immunogenicity of viral vector, prime-boost SIV vaccine regimens in infant rhesus macaques: attenuated vesicular stomatitis virus (VSV) and modified vaccinia Ankara (MVA) recombinant SIV vaccines compared to live-attenuated SIV.

    Science.gov (United States)

    Van Rompay, Koen K A; Abel, Kristina; Earl, Patricia; Kozlowski, Pamela A; Easlick, Juliet; Moore, Joseph; Buonocore-Buzzelli, Linda; Schmidt, Kimberli A; Wilson, Robert L; Simon, Ian; Moss, Bernard; Rose, Nina; Rose, John; Marthas, Marta L

    2010-02-10

    In a previously developed infant macaque model mimicking HIV infection by breast-feeding, we demonstrated that intramuscular immunization with recombinant poxvirus vaccines expressing simian immunodeficiency virus (SIV) structural proteins provided partial protection against infection following oral inoculation with virulent SIV. In an attempt to further increase systemic but also local antiviral immune responses at the site of viral entry, we tested the immunogenicity of different orally administered, replicating vaccines. One group of newborn macaques received an oral prime immunization with a recombinant vesicular stomatitis virus expressing SIVmac239 gag, pol and env (VSV-SIVgpe), followed 2 weeks later by an intramuscular boost immunization with MVA-SIV. Another group received two immunizations with live-attenuated SIVmac1A11, administered each time both orally and intravenously. Control animals received mock immunizations or non-SIV VSV and MVA control vectors. Analysis of SIV-specific immune responses in blood and lymphoid tissues at 4 weeks of age demonstrated that both vaccine regimens induced systemic antibody responses and both systemic and local cell-mediated immune responses. The safety and immunogenicity of the VSV-SIVgpe+MVA-SIV immunization regimen described in this report provide the scientific incentive to explore the efficacy of this vaccine regimen against virulent SIV exposure in the infant macaque model.

  13. Attenuation and immunogenicity of recombinant yellow fever 17D-dengue type 2 virus for rhesus monkeys

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    Galler R.

    2005-01-01

    Full Text Available A chimeric yellow fever (YF-dengue serotype 2 (dengue 2 virus was constructed by replacing the premembrane and envelope genes of the YF 17D virus with those from dengue 2 virus strains of Southeast Asian genotype. The virus grew to high titers in Vero cells and, after passage 2, was used for immunogenicity and attenuation studies in rhesus monkeys. Subcutaneous immunization of naive rhesus monkeys with the 17D-D2 chimeric virus induced a neutralizing antibody response associated with the protection of 6 of 7 monkeys against viremia by wild-type dengue 2 virus. Neutralizing antibody titers to dengue 2 were significantly lower in YF-immune animals than in YF-naive monkeys and protection against challenge with wild-type dengue 2 virus was observed in only 2 of 11 YF-immune monkeys. An anamnestic response to dengue 2, indicated by a sharp increase of neutralizing antibody titers, was observed in the majority of the monkeys after challenge with wild-type virus. Virus attenuation was demonstrated using the standard monkey neurovirulence test. The 17D-D2 chimera caused significantly fewer histological lesions than the YF 17DD virus. The attenuated phenotype could also be inferred from the limited viremias compared to the YF 17DD vaccine. Overall, these results provide further support for the use of chimeric viruses for the development of a new live tetravalent dengue vaccine.

  14. A pilot study comparing the development of EIAV Env-specific antibodies induced by DNA/recombinant vaccinia-vectored vaccines and an attenuated Chinese EIAV vaccine.

    Science.gov (United States)

    Meng, Qinglai; Lin, Yuezhi; Ma, Jian; Ma, Yan; Zhao, Liping; Li, Shenwei; Yang, Kai; Zhou, Jianhua; Shen, Rongxian; Zhang, Xiaoyan; Shao, Yiming

    2012-12-01

    Data from successful attenuated lentiviral vaccine studies indicate that fully mature Env-specific antibodies characterized by high titer, high avidity, and the predominant recognition of conformational epitopes are associated with protective efficacy. Although vaccination with a DNA prime/recombinant vaccinia-vectored vaccine boost strategy has been found to be effective in some trials with non-human primate/simian/human immunodeficiency virus (SHIV) models, it remains unclear whether this vaccination strategy could elicit mature equine infectious anemia virus (EIAV) Env-specific antibodies, thus protecting vaccinated horses against EIAV infection. Therefore, in this pilot study we vaccinated horses using a strategy based on DNA prime/recombinant Tiantan vaccinia (rTTV)-vectored vaccines encoding EIAV env and gag genes, and observed the development of Env-specific antibodies, neutralizing antibodies, and p26-specific antibodies. Vaccination with DNA induced low titer, low avidity, and the predominant recognition of linear epitopes by Env-specific antibodies, which was enhanced by boosting vaccinations with rTTV vaccines. However, the maturation levels of Env-specific antibodies induced by the DNA/rTTV vaccines were significantly lower than those induced by the attenuated vaccine EIAV(FDDV). Additionally, DNA/rTTV vaccines did not elicit broadly neutralizing antibodies. After challenge with a virulent EIAV strain, all of the vaccinees and control horses died from EIAV disease. These data indicate that the regimen of DNA prime/rTTV vaccine boost did not induce mature Env-specific antibodies, which might have contributed to immune protection failure.

  15. Oncolytic virotherapy for pediatric malignancies: future prospects

    Directory of Open Access Journals (Sweden)

    Waters AM

    2016-08-01

    Full Text Available Alicia M Waters,1 Gregory K Friedman,2 Eric K Ring,2 Elizabeth A Beierle1 1Department of Surgery, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA; 2Department of Pediatrics, Division of Hematology-Oncology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA Abstract: Pediatric solid tumors remain a major health concern, with nearly 16,000 children diagnosed each year. Of those, ~2,000 succumb to their disease, and survivors often suffer from lifelong disability secondary to toxic effects of current treatments. Countless multimodality ­treatment regimens are being explored to make advances against this deadly disease. One targeted treatment approach is oncolytic virotherapy. Conditionally replicating viruses can infect tumor cells while leaving normal cells unharmed. Four viruses have been advanced to pediatric clinical trials, including herpes simplex virus-1, Seneca Valley virus, reovirus, and vaccinia virus. In this review, we discuss the mechanism of action of each virus, pediatric preclinical studies conducted to date, past and ongoing pediatric clinical trials, and potential future direction for these novel viral therapeutics. Keywords: oncolytic virus, herpes simplex virus, Seneca Valley virus, reovirus, vaccinia

  16. Interferon γ expressed by a recombinant respiratory syncytial virus attenuates virus replication in mice without compromising immunogenicity

    OpenAIRE

    1999-01-01

    Interferon γ (IFN-γ) has pleiotropic biological effects, including intrinsic antiviral activity as well as stimulation and regulation of immune responses. An infectious recombinant human respiratory syncytial virus (rRSV/mIFN-γ) was constructed that encodes murine (m) IFN-γ as a separate gene inserted into the G-F intergenic region. Cultured cells infected with rRSV/mIFN-γ secreted 22 μg mIFN-γ per 106 cells. The replication of rRSV/mIFN-γ, but not that of a control chimeric rRSV containing t...

  17. Making Common Sense of Vaccines: An Example of Discussing the Recombinant Attenuated Salmonella Vaccine with the Public.

    Science.gov (United States)

    Dankel, Dorothy J; Roland, Kenneth L; Fisher, Michael; Brenneman, Karen; Delgado, Ana; Santander, Javier; Baek, Chang-Ho; Clark-Curtiss, Josephine; Strand, Roger; Curtiss, Roy

    2014-01-01

    Researchers have iterated that the future of synthetic biology and biotechnology lies in novel consumer applications of crossing biology with engineering. However, if the new biology's future is to be sustainable, early and serious efforts must be made towards social sustainability. Therefore, the crux of new applications of synthetic biology and biotechnology is public understanding and acceptance. The RASVaccine is a novel recombinant design not found in nature that re-engineers a common bacteria (Salmonella) to produce a strong immune response in humans. Synthesis of the RASVaccine has the potential to improve public health as an inexpensive, non-injectable product. But how can scientists move forward to create a dialogue of creating a 'common sense' of this new technology in order to promote social sustainability? This paper delves into public issues raised around these novel technologies and uses the RASVaccine as an example of meeting the public with a common sense of its possibilities and limitations.

  18. Vaccination with recombinant Mycobacterium tuberculosis PknD attenuates bacterial dissemination to the brain in guinea pigs.

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    Ciaran Skerry

    Full Text Available BACKGROUND: We have previously identified Mycobacterium tuberculosis PknD to be an important virulence factor required for the pathogenesis of central nervous system (CNS tuberculosis (TB. Specifically, PknD mediates bacillary invasion of the blood-brain barrier, which can be neutralized by specific antisera, suggesting its potential role as a therapeutic target against TB meningitis. METHODOLOGY/PRINCIPAL FINDINGS: We utilized an aerosol challenge guinea pig model of CNS TB and compared the protective efficacy of recombinant M. tuberculosis PknD subunit protein with that of M. bovis BCG against bacillary dissemination to the brain. BCG vaccination limited the pulmonary bacillary burden after aerosol challenge with virulent M. tuberculosis in guinea pigs and also reduced bacillary dissemination to the brain (P = 0.01. PknD vaccination also offered significant protection against bacterial dissemination to the brain, which was no different from BCG (P>0.24, even though PknD vaccinated animals had almost 100-fold higher pulmonary bacterial burdens. Higher levels of PknD-specific IgG were noted in animals immunized with PknD, but not in BCG-vaccinated or control animals. Furthermore, pre-incubation of M. tuberculosis with sera from PknD-vaccinated animals, but not with sera from BCG-vaccinated or control animals, significantly reduced bacterial invasion in a human blood-brain barrier model (P<0.01. CONCLUSION: Current recommendations for administering BCG at birth are based on protection gained against severe disease, such as TB meningitis, during infancy. We demonstrate that vaccination with recombinant M. tuberculosis PknD subunit offers a novel strategy to protect against TB meningitis, which is equivalent to BCG in a guinea pig model. Moreover, since BCG lacks the PknD sensor, BCG could also be boosted to develop a more effective vaccine against TB meningitis, a devastating disease that disproportionately affects young children.

  19. Oncolytic virotherapy for pediatric malignancies: future prospects

    Science.gov (United States)

    Waters, Alicia M; Friedman, Gregory K; Ring, Eric K; Beierle, Elizabeth A

    2016-01-01

    Pediatric solid tumors remain a major health concern, with nearly 16,000 children diagnosed each year. Of those, ~2,000 succumb to their disease, and survivors often suffer from lifelong disability secondary to toxic effects of current treatments. Countless multimodality treatment regimens are being explored to make advances against this deadly disease. One targeted treatment approach is oncolytic virotherapy. Conditionally replicating viruses can infect tumor cells while leaving normal cells unharmed. Four viruses have been advanced to pediatric clinical trials, including herpes simplex virus-1, Seneca Valley virus, reovirus, and vaccinia virus. In this review, we discuss the mechanism of action of each virus, pediatric preclinical studies conducted to date, past and ongoing pediatric clinical trials, and potential future direction for these novel viral therapeutics. PMID:27579298

  20. Attenuation of skeletal muscle wasting with recombinant human growth hormone secreted from a tissue-engineered bioartificial muscle

    Science.gov (United States)

    Vandenburgh, H.; Del Tatto, M.; Shansky, J.; Goldstein, L.; Russell, K.; Genes, N.; Chromiak, J.; Yamada, S.

    1998-01-01

    Skeletal muscle wasting is a significant problem in elderly and debilitated patients. Growth hormone (GH) is an anabolic growth factor for skeletal muscle but is difficult to deliver in a therapeutic manner by injection owing to its in vivo instability. A novel method is presented for the sustained secretion of recombinant human GH (rhGH) from genetically modified skeletal muscle implants, which reduces host muscle wasting. Proliferating murine C2C12 skeletal myoblasts stably transduced with the rhGH gene were tissue engineered in vitro into bioartificial muscles (C2-BAMs) containing organized postmitotic myofibers secreting 3-5 microg of rhGH/day in vitro. When implanted subcutaneously into syngeneic mice, C2-BAMs delivered a sustained physiologic dose of 2.5 to 11.3 ng of rhGH per milliliter of serum. rhGH synthesized and secreted by the myofibers was in the 22-kDa monomeric form and was biologically active, based on downregulation of a GH-sensitive protein synthesized in the liver. Skeletal muscle disuse atrophy was induced in mice by hindlimb unloading, causing the fast plantaris and slow soleus muscles to atrophy by 21 to 35% ( muscle-wasting disorders.

  1. Recombinant Human Leptin Does Not Alter Gut Hormone Levels after Gastric Bypass but May Attenuate Sweet Cravings

    Directory of Open Access Journals (Sweden)

    Rushika Conroy

    2014-01-01

    Full Text Available Bariatric surgery improves glucose homeostasis and alters gut hormones partly independent of weight loss. Leptin plays a role in these processes; levels are decreased following bariatric surgery, creating a relative leptin insufficiency. We previously showed that leptin administration in a weight-reduced state after Roux-en-Y gastric bypass (RYGB caused no further weight loss. Here, we discuss the impact of leptin administration on gut hormones, glucostasis, and appetite. Weight stable women after RYGB were randomized to receive placebo or recombinant human metreleptin (0.05 mg/kg twice daily. At weeks 0 and 16, a liquid meal challenge was performed. Glucose, insulin, C-peptide, GLP-1, PYY, glucagon, and ghrelin (total, acyl, and desacyl were measured fasting and postprandially. Appetite was assessed using a visual analog scale. Mean post-op period was 53±2.3 months; mean BMI was 34.6±0.2 kg/m2. At 16 weeks, there was no significant change in weight within or between groups. Fasting PYY was significantly different between groups and the leptin group had lower sweets craving at week 16 than the placebo group (P<0.05. No other differences were observed. Leptin replacement does not alter gut hormones or glucostasis but may diminish sweet cravings compared to placebo in this population of post-RYGB women.

  2. Gene transfer of GLT-1, a glial glutamate transporter, into the spinal cord by recombinant adenovirus attenuates inflammatory and neuropathic pain in rats

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    Nakagawa Takayuki

    2008-12-01

    Full Text Available Abstract Background The glial glutamate transporter GLT-1 is abundantly expressed in astrocytes and is crucial for glutamate removal from the synaptic cleft. Decreases in glutamate uptake activity and expression of spinal glutamate transporters are reported in animal models of pathological pain. However, the lack of available specific inhibitors and/or activators for GLT-1 makes it difficult to determine the roles of spinal GLT-1 in inflammatory and neuropathic pain. In this study, we examined the effect of gene transfer of GLT-1 into the spinal cord with recombinant adenoviruses on the inflammatory and neuropathic pain in rats. Results Intraspinal infusion of adenoviral vectors expressing the GLT-1 gene increased GLT-1 expression in the spinal cord 2–21 days after the infusion. Transgene expression was primarily localized to astrocytes. The spinal GLT-1 gene transfer had no effect on acute mechanical and thermal nociceptive responses in naive rats, whereas it significantly reduced the inflammatory mechanical hyperalgesia induced by hindlimb intraplantar injection of carrageenan/kaolin. Spinal GLT-1 gene transfer 7 days before partial sciatic nerve ligation recovered the extent of the spinal GLT-1 expression in the membrane fraction that was decreased following the nerve ligation, and prevented the induction of tactile allodynia. However, the partial sciatic nerve ligation-induced allodynia was not reversed when the adenoviruses were infused 7 or 14 days after the nerve ligation. Conclusion These results suggest that overexpression of GLT-1 on astrocytes in the spinal cord by recombinant adenoviruses attenuates the induction, but not maintenance, of inflammatory and neuropathic pain, probably by preventing the induction of central sensitization, without affecting acute pain sensation. Upregulation or functional enhancement of spinal GLT-1 could be a novel strategy for the prevention of pathological pain.

  3. Recombinant human MFG-E8 attenuates intestinal injury and mortality in severe whole body irradiation in rats.

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    Michael A Ajakaiye

    Full Text Available The gastrointestinal (GI syndrome component of acute radiation syndrome (ARS results from depletion of immature parenchymal stem cells after high dose irradiation and contributes significantly to early mortality. It is associated with severe, irreparable damage in the GI tract and extremely low survival. There is a need for the development of viable mitigators of whole body irradiation (WBI due to the possibility of unexpected high level radiation exposure from nuclear accidents or attacks. We therefore examined the effect of recombinant human milk fat globule-EGF factor 8 (rhMFG-E8 in mitigating damage after WBI. Male Sprague-Dawley rats were exposed to 10 Gy WBI using Cesium-137 as the radiation source. The animals in the treatment group received rhMFG-E8 (166 µg/kg BW subcutaneously once a day with the first dose given 6 h after WBI. Blood and tissue samples from the ileum were collected after 3 days of treatment. A separate cohort of animals was treated for 7 days and the 21 day mortality rate was determined. Treatment with rhMFG-E8 significantly improved the survival from 31% to 75% over 21 days. Furthermore, rhMFG-E8 treatment resulted in a 36% reduction in the radiation injury intestinal mucosal damage score, corresponding to visible histological changes. MFG-E8 gene expression was significantly decreased in WBI-induced animals as compared to sham controls. Treatment with rhMFG-E8 increased p53 and p21 expression by 207% and 84% compared to untreated controls. This was accompanied by an 80% increase in the expression of anti-apoptotic cell regulator Bcl-2. p53 and p21 levels correlate with improved survival after radiation injury. These cell regulators arrest the cell after DNA damage and enable DNA repair as well as optimize cell survival. Taken together, these results indicate that rhMFG-E8 ameliorates the GI syndrome and improves survival after WBI by minimizing intestinal cell damage and optimizing recovery.

  4. Truncated recombinant human SP-D attenuates emphysema and type II cell changes in SP-D deficient mice

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    Mühlfeld Christian

    2007-10-01

    Full Text Available Abstract Background Surfactant protein D (SP-D deficient mice develop emphysema-like pathology associated with focal accumulations of foamy alveolar macrophages, an excess of surfactant phospholipids in the alveolar space and both hypertrophy and hyperplasia of alveolar type II cells. These findings are associated with a chronic inflammatory state. Treatment of SP-D deficient mice with a truncated recombinant fragment of human SP-D (rfhSP-D has been shown to decrease the lipidosis and alveolar macrophage accumulation as well as production of proinflammatory chemokines. The aim of this study was to investigate if rfhSP-D treatment reduces the structural abnormalities in parenchymal architecture and type II cells characteristic of SP-D deficiency. Methods SP-D knock-out mice, aged 3 weeks, 6 weeks and 9 weeks were treated with rfhSP-D for 9, 6 and 3 weeks, respectively. All mice were sacrificed at age 12 weeks and compared to both PBS treated SP-D deficient and wild-type groups. Lung structure was quantified by design-based stereology at the light and electron microscopic level. Emphasis was put on quantification of emphysema, type II cell changes and intracellular surfactant. Data were analysed with two sided non-parametric Mann-Whitney U-test. Main Results After 3 weeks of treatment, alveolar number was higher and mean alveolar size was smaller compared to saline-treated SP-D knock-out controls. There was no significant difference concerning these indices of pulmonary emphysema within rfhSP-D treated groups. Type II cell number and size were smaller as a consequence of treatment. The total volume of lamellar bodies per type II cell and per lung was smaller after 6 weeks of treatment. Conclusion Treatment of SP-D deficient mice with rfhSP-D leads to a reduction in the degree of emphysema and a correction of type II cell hyperplasia and hypertrophy. This supports the concept that rfhSP-D might become a therapeutic option in diseases that are

  5. Oncolytic Seneca Valley Virus: past perspectives and future directions

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    Burke MJ

    2016-09-01

    Full Text Available Michael J Burke Department of Pediatrics, Division of Pediatric Oncology, Medical College of Wisconsin, MACC Fund Research Center, Milwaukee, WI, USA Abstract: Seneca Valley Virus isolate 001 (SVV-001 is an oncolytic RNA virus of the Picornaviridae family. It is also the first picornavirus discovered of the novel genus Senecavirus. SVV-001 replicates through an RNA intermediate, bypassing a DNA phase, and is unable to integrate into the host genome. SVV-001 was originally discovered as a contaminant in the cell culture of fetal retinoblasts and has since been identified as a potent oncolytic virus against tumors of neuroendocrine origin. SVV-001 has a number of features that make it an attractive oncolytic virus, namely, its ability to target and penetrate solid tumors via intravenous administration, inability for insertional mutagenesis, and being a self-replicating RNA virus with selective tropism for cancer cells. SVV-001 has been studied in both pediatric and adult early phase studies reporting safety and some clinical efficacy, albeit primarily in adult tumors. This review summarizes the current knowledge of SVV-001 and what its future as an oncolytic virus may hold. Keywords: oncolytic, virus, oncology, Seneca, valley

  6. Oncolytic Virotherapy for Multiple Myeloma: Past, Present, and Future

    Directory of Open Access Journals (Sweden)

    Chandini M. Thirukkumaran

    2011-01-01

    Full Text Available Multiple myeloma (MM is a B-cell malignancy that is currently felt to be incurable. Despite recently approved novel targeted treatments such as lenalidomide and bortezomib, most MM patients' relapse is emphasizing the need for effective and well-tolerated therapies for this deadly disease. The use of oncolytic viruses has garnered significant interest as cancer therapeutics in recent years, and are currently under intense clinical investigation. Both naturally occurring and engineered DNA and RNA viruses have been investigated preclinically as treatment modalities for several solid and hematological malignancies. Presently, only a genetically modified measles virus is in human clinical trials for MM. The information obtained from this and other future clinical trials will guide clinical application of oncolytic viruses as anticancer agents for MM. This paper provides a timely overview of the history of oncolytic viruses for the treatment of MM and future strategies for the optimization of viral therapy for this disease.

  7. Tumor-Associated Macrophages in Oncolytic Virotherapy: Friend or Foe?

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    Nicholas L. Denton

    2016-07-01

    Full Text Available Cancer therapy remains a challenge due to toxicity limitations of chemotherapy and radiation therapy. Oncolytic viruses that selectively replicate and destroy cancer cells are of increasing interest. In addition to direct cell lysis, these vectors stimulate an anti-tumor immune response. A key regulator of tumor immunity is the tumor-associated macrophage population. Macrophages can either support oncolytic virus therapy through pro-inflammatory stimulation of the anti-tumor response at the cost of hindering direct oncolysis or through immunosuppressive protection of virus replication at the cost of hindering the anti-tumor immune response. Despite similarities in macrophage interaction between adult and pediatric tumors and the abundance of research supporting macrophage modulation in adult tumors, there are few studies investigating macrophage modulation in pediatric cancers or modulation of immunotherapy. We review the current state of knowledge regarding macrophages in cancers and their influence on oncolytic virotherapy.

  8. Oncolytic Viruses: Therapeutics With an Identity Crisis.

    Science.gov (United States)

    Breitbach, Caroline J; Lichty, Brian D; Bell, John C

    2016-07-01

    Oncolytic viruses (OV) are replicating viral therapeutics for the treatment of cancer and have been in laboratory development for about twenty years. Recently, the FDA approved Imlygic, a herpes virus based therapeutic for the treatment of melanoma and thus OVs have entered a new era where they are a weapon in the armament of the oncologist. OVs are unique therapeutics with multiple mechanisms of therapeutic activity. The exact path for their development and eventual uptake by pharmaceutical companies is somewhat clouded by an uncertain identity. Are they vaccines, tumour lysing therapeutics, inducers of innate immunity, gene therapy vectors, anti-vascular agents or all of the above? Should they be developed as stand-alone loco-regional therapeutics, systemically delivered tumour hunters or immune modulators best tested as combination therapeutics? We summarize data here supporting the idea, depending upon the virus, that OVs can be any or all of these things. Pursuing a "one-size fits all" approach is counter-productive to their clinical development and instead as a field we should build on the strengths of individual virus platforms.

  9. Oncolytic Viruses: Therapeutics With an Identity Crisis

    Directory of Open Access Journals (Sweden)

    Caroline J. Breitbach

    2016-07-01

    Full Text Available Oncolytic viruses (OV are replicating viral therapeutics for the treatment of cancer and have been in laboratory development for about twenty years. Recently, the FDA approved Imlygic, a herpes virus based therapeutic for the treatment of melanoma and thus OVs have entered a new era where they are a weapon in the armament of the oncologist. OVs are unique therapeutics with multiple mechanisms of therapeutic activity. The exact path for their development and eventual uptake by pharmaceutical companies is somewhat clouded by an uncertain identity. Are they vaccines, tumour lysing therapeutics, inducers of innate immunity, gene therapy vectors, anti-vascular agents or all of the above? Should they be developed as stand-alone loco-regional therapeutics, systemically delivered tumour hunters or immune modulators best tested as combination therapeutics? We summarize data here supporting the idea, depending upon the virus, that OVs can be any or all of these things. Pursuing a “one-size fits all” approach is counter-productive to their clinical development and instead as a field we should build on the strengths of individual virus platforms.

  10. Recombinant mumps virus as a cancer therapeutic agent.

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    Ammayappan, Arun; Russell, Stephen J; Federspiel, Mark J

    2016-01-01

    Mumps virus belongs to the family of Paramyxoviridae and has the potential to be an oncolytic agent. Mumps virus Urabe strain had been tested in the clinical setting as a treatment for human cancer four decades ago in Japan. These clinical studies demonstrated that mumps virus could be a promising cancer therapeutic agent that showed significant antitumor activity against various types of cancers. Since oncolytic virotherapy was not in the limelight until the beginning of the 21(st) century, the interest to pursue mumps virus for cancer treatment slowly faded away. Recent success stories of oncolytic clinical trials prompted us to resurrect the mumps virus and to explore its potential for cancer treatment. We have obtained the Urabe strain of mumps virus from Osaka University, Japan, which was used in the earlier human clinical trials. In this report we describe the development of a reverse genetics system from a major isolate of this Urabe strain mumps virus stock, and the construction and characterization of several recombinant mumps viruses with additional transgenes. We present initial data demonstrating these recombinant mumps viruses have oncolytic activity against tumor cell lines in vitro and some efficacy in preliminary pilot animal tumor models.

  11. Big Data Offers Novel Insights for Oncolytic Virus Immunotherapy

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    Swift, Stephanie L.; Stojdl, David F.

    2016-01-01

    Large-scale assays, such as microarrays, next-generation sequencing and various “omics” technologies, have explored multiple aspects of the immune response following virus infection, often from a public health perspective. Yet a lack of similar data exists for monitoring immune engagement during oncolytic virus immunotherapy (OVIT) in the cancer setting. Tracking immune signatures at the tumour site can create a snapshot or longitudinally analyse immune cell activation, infiltration and functionality within global populations or individual cells. Mapping immune changes over the course of oncolytic biotherapy—from initial infection to tumour stabilisation/regression through to long-term cure or escape/relapse—has the potential to generate important therapeutic insights around virus-host interactions. Further, correlating such immune signatures with specific tumour outcomes has significant value for guiding the development of novel oncolytic virus immunotherapy strategies. Here, we provide insights for OVIT from large-scale analyses of immune populations in the infection, vaccination and immunotherapy setting. We analyse several approaches to manipulating immune engagement during OVIT. We further explore immunocentric changes in the tumour tissue following immunotherapy, and compile several immune signatures of therapeutic success. Ultimately, we highlight clinically relevant large-scale approaches with the potential to strengthen future oncolytic strategies to optimally engage the immune system. PMID:26861383

  12. Luciferase imaging for evaluation of oncolytic adenovirus replication in vivo.

    Science.gov (United States)

    Guse, K; Dias, J D; Bauerschmitz, G J; Hakkarainen, T; Aavik, E; Ranki, T; Pisto, T; Särkioja, M; Desmond, R A; Kanerva, A; Hemminki, A

    2007-06-01

    Oncolytic viruses kill cancer cells by tumor-selective replication. Clinical data have established the safety of the approach but also the need of improvements in potency. Efficacy of oncolysis is linked to effective infection of target cells and subsequent productive replication. Other variables include intratumoral barriers, access to target cells, uptake by non-target organs and immune response. Each of these aspects relates to the location and degree of virus replication. Unfortunately, detection of in vivo replication has been difficult, labor intensive and costly and therefore not much studied. We hypothesized that by coinfection of a luciferase expressing E1-deleted virus with an oncolytic virus, both viruses would replicate when present in the same cell. Photon emission due to conversion of D-Luciferin is sensitive and penetrates tissues well. Importantly, killing of animals is not required and each animal can be imaged repeatedly. Two different murine xenograft models were used and intratumoral coinjections of luciferase encoding virus were performed with eight different oncolytic adenoviruses. In both models, we found significant correlation between photon emission and infectious virus production. This suggests that the system can be used for non-invasive quantitation of the amplitude, persistence and dynamics of oncolytic virus replication in vivo, which could be helpful for the development of more effective and safe agents.

  13. Replication-selective oncolytic viruses in the treatment of cancer.

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    Everts, Bart; van der Poel, Henk G

    2005-02-01

    In the search for novel strategies, oncolytic virotherapy has recently emerged as a viable approach to specifically kill tumor cells. Unlike conventional gene therapy, it uses replication competent viruses that are able to spread through tumor tissue by virtue of viral replication and concomitant cell lysis. Recent advances in molecular biology have allowed the design of several genetically modified viruses, such as adenovirus and herpes simplex virus that specifically replicate in, and kill tumor cells. On the other hand, viruses with intrinsic oncolytic capacity are also being evaluated for therapeutic purposes. In this review, an overview is given of the general mechanisms and genetic modifications by which these viruses achieve tumor cell-specific replication and antitumor efficacy. However, although generally the oncolytic efficacy of these approaches has been demonstrated in preclinical studies the therapeutic efficacy in clinical trails is still not optimal. Therefore, strategies are evaluated that could further enhance the oncolytic potential of conditionally replicating viruses. In this respect, the use of tumor-selective viruses in conjunction with other standard therapies seems most promising. However, still several hurdles regarding clinical limitations and safety issues should be overcome before this mode of therapy can become of clinical relevance.

  14. Oncolytic Seneca Valley Virus: past perspectives and future directions.

    Science.gov (United States)

    Burke, Michael J

    2016-01-01

    Seneca Valley Virus isolate 001 (SVV-001) is an oncolytic RNA virus of the Picornaviridae family. It is also the first picornavirus discovered of the novel genus Senecavirus. SVV-001 replicates through an RNA intermediate, bypassing a DNA phase, and is unable to integrate into the host genome. SVV-001 was originally discovered as a contaminant in the cell culture of fetal retinoblasts and has since been identified as a potent oncolytic virus against tumors of neuroendocrine origin. SVV-001 has a number of features that make it an attractive oncolytic virus, namely, its ability to target and penetrate solid tumors via intravenous administration, inability for insertional mutagenesis, and being a self-replicating RNA virus with selective tropism for cancer cells. SVV-001 has been studied in both pediatric and adult early phase studies reporting safety and some clinical efficacy, albeit primarily in adult tumors. This review summarizes the current knowledge of SVV-001 and what its future as an oncolytic virus may hold.

  15. Insertion of the human sodium iodide symporter to facilitate deep tissue imaging does not alter oncolytic or replication capability of a novel vaccinia virus

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    Mittra Arjun

    2011-03-01

    Full Text Available Abstract Introduction Oncolytic viruses show promise for treating cancer. However, to assess therapeutic efficacy and potential toxicity, a noninvasive imaging modality is needed. This study aimed to determine if insertion of the human sodium iodide symporter (hNIS cDNA as a marker for non-invasive imaging of virotherapy alters the replication and oncolytic capability of a novel vaccinia virus, GLV-1h153. Methods GLV-1h153 was modified from parental vaccinia virus GLV-1h68 to carry hNIS via homologous recombination. GLV-1h153 was tested against human pancreatic cancer cell line PANC-1 for replication via viral plaque assays and flow cytometry. Expression and transportation of hNIS in infected cells was evaluated using Westernblot and immunofluorescence. Intracellular uptake of radioiodide was assessed using radiouptake assays. Viral cytotoxicity and tumor regression of treated PANC-1tumor xenografts in nude mice was also determined. Finally, tumor radiouptake in xenografts was assessed via positron emission tomography (PET utilizing carrier-free 124I radiotracer. Results GLV-1h153 infected, replicated within, and killed PANC-1 cells as efficiently as GLV-1h68. GLV-1h153 provided dose-dependent levels of hNIS expression in infected cells. Immunofluorescence detected transport of the protein to the cell membrane prior to cell lysis, enhancing hNIS-specific radiouptake (P In vivo, GLV-1h153 was as safe and effective as GLV-1h68 in regressing pancreatic cancer xenografts (P 124I-PET. Conclusion Insertion of the hNIS gene does not hinder replication or oncolytic capability of GLV-1h153, rendering this novel virus a promising new candidate for the noninvasive imaging and tracking of oncolytic viral therapy.

  16. Going viral: a review of replication-selective oncolytic adenoviruses.

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    Larson, Christopher; Oronsky, Bryan; Scicinski, Jan; Fanger, Gary R; Stirn, Meaghan; Oronsky, Arnold; Reid, Tony R

    2015-08-21

    Oncolytic viruses have had a tumultuous course, from the initial anecdotal reports of patients having antineoplastic effects after natural viral infections a century ago to the development of current cutting-edge therapies in clinical trials. Adenoviruses have long been the workhorse of virotherapy, and we review both the scientific and the not-so-scientific forces that have shaped the development of these therapeutics from wild-type viral pathogens, turning an old foe into a new friend. After a brief review of the mechanics of viral replication and how it has been modified to engineer tumor selectivity, we give particular attention to ONYX-015, the forerunner of virotherapy with extensive clinical testing that pioneered the field. The findings from those as well as other oncolytic trials have shaped how we now view these viruses, which our immune system has evolved to vigorously attack, as promising immunotherapy agents.

  17. Oncolytic Viruses in the Treatment of Bladder Cancer

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    Kyle G. Potts

    2012-01-01

    Full Text Available Bladder carcinoma is the second most common malignancy of the urinary tract. Up to 85% of patients with bladder cancer are diagnosed with a tumor that is limited to the bladder mucosa (Ta, T1, and CIS. These stages are commonly termed as non-muscle-invasive bladder cancer (NMIBC. Although the treatment of NMIBC has greatly improved in recent years, there is a need for additional therapies when patients fail bacillus Calmette-Guérin (BCG and chemotherapeutic agents. We propose that bladder cancer may be an ideal target for oncolytic viruses engineered to selectively replicate in and lyse tumor cells leaving normal cells unharmed. In support of this hypothesis, here we review current treatment strategies for bladder cancer and their shortcomings, as well as recent advancements in oncolytic viral therapy demonstrating encouraging safety profiles and antitumor activity.

  18. Measles to the Rescue: A Review of Oncolytic Measles Virus

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    Sarah Aref

    2016-10-01

    Full Text Available Oncolytic virotherapeutic agents are likely to become serious contenders in cancer treatment. The vaccine strain of measles virus is an agent with an impressive range of oncolytic activity in pre-clinical trials with increasing evidence of safety and efficacy in early clinical trials. This paramyxovirus vaccine has a proven safety record and is amenable to careful genetic modification in the laboratory. Overexpression of the measles virus (MV receptor CD46 in many tumour cells may direct the virus to preferentially enter transformed cells and there is increasing awareness of the importance of nectin-4 and signaling lymphocytic activation molecule (SLAM in oncolysis. Successful attempts to retarget MV by inserting genes for tumour-specific ligands to antigens such as carcinoembryonic antigen (CEA, CD20, CD38, and by engineering the virus to express synthetic microRNA targeting sequences, and “blinding” the virus to the natural viral receptors are exciting measures to increase viral specificity and enhance the oncolytic effect. Sodium iodine symporter (NIS can also be expressed by MV, which enables in vivo tracking of MV infection. Radiovirotherapy using MV-NIS, chemo-virotherapy to convert prodrugs to their toxic metabolites, and immune-virotherapy including incorporating antibodies against immune checkpoint inhibitors can also increase the oncolytic potential. Anti-viral host immune responses are a recognized barrier to the success of MV, and approaches such as transporting MV to the tumour sites by carrier cells, are showing promise. MV Clinical trials are producing encouraging preliminary results in ovarian cancer, myeloma and cutaneous non-Hodgkin lymphoma, and the outcome of currently open trials in glioblastoma multiforme, mesothelioma and squamous cell carcinoma are eagerly anticipated.

  19. Modelling Spread of Oncolytic Viruses in Heterogeneous Cell Populations

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    Ellis, Michael; Dobrovolny, Hana

    2014-03-01

    One of the most promising areas in current cancer research and treatment is the use of viruses to attack cancer cells. A number of oncolytic viruses have been identified to date that possess the ability to destroy or neutralize cancer cells while inflicting minimal damage upon healthy cells. Formulation of predictive models that correctly describe the evolution of infected tumor systems is critical to the successful application of oncolytic virus therapy. A number of different models have been proposed for analysis of the oncolytic virus-infected tumor system, with approaches ranging from traditional coupled differential equations such as the Lotka-Volterra predator-prey models, to contemporary modeling frameworks based on neural networks and cellular automata. Existing models are focused on tumor cells and the effects of virus infection, and offer the potential for improvement by including effects upon normal cells. We have recently extended the traditional framework to a 2-cell model addressing the full cellular system including tumor cells, normal cells, and the impacts of viral infection upon both populations. Analysis of the new framework reveals complex interaction between the populations and potential inability to simultaneously eliminate the virus and tumor populations.

  20. Oncolytic Replication of E1b-Deleted Adenoviruses

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    Pei-Hsin Cheng

    2015-11-01

    Full Text Available Various viruses have been studied and developed for oncolytic virotherapies. In virotherapy, a relatively small amount of viruses used in an intratumoral injection preferentially replicate in and lyse cancer cells, leading to the release of amplified viral particles that spread the infection to the surrounding tumor cells and reduce the tumor mass. Adenoviruses (Ads are most commonly used for oncolytic virotherapy due to their infection efficacy, high titer production, safety, easy genetic modification, and well-studied replication characteristics. Ads with deletion of E1b55K preferentially replicate in and destroy cancer cells and have been used in multiple clinical trials. H101, one of the E1b55K-deleted Ads, has been used for the treatment of late-stage cancers as the first approved virotherapy agent. However, the mechanism of selective replication of E1b-deleted Ads in cancer cells is still not well characterized. This review will focus on three potential molecular mechanisms of oncolytic replication of E1b55K-deleted Ads. These mechanisms are based upon the functions of the viral E1B55K protein that are associated with p53 inhibition, late viralmRNAexport, and cell cycle disruption.

  1. Delta-24-RGD oncolytic adenovirus elicits anti-glioma immunity in an immunocompetent mouse model

    NARCIS (Netherlands)

    H. Jiang (Hao); K. Clise-Dwyer (Karen); K.E. Ruisaard (Kathryn); X. Fan (Xuejun); W. Tian (Weihua); J. Gumin (Joy); M.L.M. Lamfers (Martine); A. Kleijn (Anne); F.F. Lang (Frederick); S. Yung (Sun); L.M. Vence (Luis); C. Gomez-Manzano (Candelaria); J. Fueyo (Juan)

    2014-01-01

    textabstractBackground: Emerging evidence suggests anti-cancer immunity is involved in the therapeutic effect induced by oncolytic viruses. Here we investigate the effect of Delta-24-RGD oncolytic adenovirus on innate and adaptive anti-glioma immunity. Design: Mouse GL261-glioma model was set up in

  2. Construction of a novel oncolytic adenoviral vector and its biological characteristics.

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    Zhang, Mingzhi; Zhang, Xudong; Han, Zhiqiang; Chen, Xinfeng; Yang, Li; Sheng, Yuqiao; Wen, Jianguo

    2013-02-01

    In this study, we aimed to construct an effective and safe oncolytic adenoviral vector for cancer treatment with gene therapy. First, the promoter of the catalytic subunit of human telomerase (hTERTp), adenovirus early region 1a gene (E1A) and thymidine kinase gene of human herpes virus type 1 (HSV-1-TK) were amplified by using PCR from genomic DNA of 293A cells and wild-type HSV-1 (wHSV-1). These specially-prepared elements were inserted into an adenoviral shuttle vector in the opposite and the same directions of left inverted terminal repeat (L-ITR), respectively, to construct pENTR-E1A-IRES-TK-hTERTp (pEITH) and pENTR-hTERTp-E1A-IRES-TK (pHEIT). LR reaction between adenoviral shuttle vectors (pEITH and pHEIT) and the backbone vector DEST was carried out to establish adenoviral expression vectors pAd-E1A-IRES-TK-hTERTp (pAd-EITH) and pAd-hTERTp-E1A-IRES-TK (pAd-HEIT). Recombinant adenovirus Ad-EITH and Ad-HEIT were produced by transfecting 293A cells and purified for the subsequent studies of titer measurement, replication capability with and without acyclovir (ACV) and antitumor ability with and without ganciclovir (GCV) to evaluate the biological characteristics. Adenoviral shuttle vectors pEITH and pHEIT and expression vectors pAd-EITH and pAd-HEIT were successfully constructed, and recombinant adenoviruses Ad-EITH and Ad-HEIT with high titer were produced. The results of replication and cytotoxicity assays showed that Ad-EITH and Ad-HEIT replicated in the hTERTp (+) human nasopharyngeal carcinoma cell line CNE and expressed the TK gene effectively leading to the death of tumor cells. In addition, there were still some Ad-HEIT particles replicating in the hTERTp (-) human osteosarcoma U-2OS cells and human lung HFL-1 fibroblasts compared to Ad-EITH which was hardly able to replicate in U-2OS and HFL-1 cells. In addition, we also observed an interesting phenomenon, that the replication of Ad-EITH could be inhibited by antiviral drug ACV on account of the

  3. Oncolytic virotherapy in veterinary medicine: current status and future prospects for canine patients

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    Patil Sandeep S

    2012-01-01

    Full Text Available Abstract Oncolytic viruses refer to those that are able to eliminate malignancies by direct targeting and lysis of cancer cells, leaving non-cancerous tissues unharmed. Several oncolytic viruses including adenovirus strains, canine distemper virus and vaccinia virus strains have been used for canine cancer therapy in preclinical studies. However, in contrast to human studies, clinical trials with oncolytic viruses for canine cancer patients have not been reported. An 'ideal' virus has yet to be identified. This review is focused on the prospective use of oncolytic viruses in the treatment of canine tumors - a knowledge that will undoubtedly contribute to the development of oncolytic viral agents for canine cancer therapy in the future.

  4. Oncolytic herpes viruses, chemotherapeutics, and other cancer drugs

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    Braidwood L

    2013-12-01

    Full Text Available Lynne Braidwood,1 Sheila V Graham,2 Alex Graham,1 Joe Conner11Virttu Biologics Ltd, Department of Neurology, Southern General Hospital, Glasgow, UK; 2MRC-University of Glasgow Centre for Virus Research, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Jarrett Building, University of Glasgow, Glasgow, UKAbstract: Oncolytic viruses are emerging as a potential new way of treating cancers. They are selectively replication-competent viruses that propagate only in actively dividing tumor cells but not in normal cells and, as a result, destroy the tumor cells by consequence of lytic infection. At least six different oncolytic herpes simplex viruses (oHSVs have undergone clinical trials worldwide to date, and they have demonstrated an excellent safety profile and intimations of efficacy. The first pivotal Phase III trial with an oHSV, talimogene laherparepvec (T-Vec [OncoVexGM-CSF], is almost complete, with extremely positive early results reported. Intuitively, therapeutically beneficial interactions between oHSV and chemotherapeutic and targeted therapeutic drugs would be limited as the virus requires actively dividing cells for maximum replication efficiency and most anticancer agents are cytotoxic or cytostatic. However, combinations of such agents display a range of responses, with antagonistic, additive, or, perhaps most surprisingly, synergistic enhancement of antitumor activity. When synergistic interactions in cancer cell killing are observed, chemotherapy dose reductions that achieve the same overall efficacy may be possible, resulting in a valuable reduction of adverse side effects. Therefore, the combination of an oHSV with “standard-of-care” drugs makes a logical and reasonable approach to improved therapy, and the addition of a targeted oncolytic therapy with “standard-of-care” drugs merits further investigation, both preclinically and in the clinic. Numerous publications report

  5. Enhanced performance of dye-sensitized solar cells with dual-function coadsorbent: reducing the surface concentration of dye-iodine complexes concomitant with attenuated charge recombination.

    Science.gov (United States)

    Mazloum-Ardakani, Mohammad; Khoshroo, Alireza

    2015-09-21

    In this paper, we have investigated the effects of oleic acid as a dual-function coadsorbent on recombination and iodine binding in dye-sensitized solar cells. Oleic acid as a dual-function coadsorbent effectively shields the back electron transfer from TiO2 to I3(-) ions and also reduces the surface concentration of dye-I2 complexes via iodine binding to the unsaturated double bond on oleic acid. It was found that interaction between iodine and the double bond of oleic acid keeps the iodine molecules away from the surface and reduces the recombination rate between injected electrons in a semiconductor and iodine molecules and also increases open-circuit voltage. Furthermore, the interaction between iodine molecules and unexcited dyes affects the UV-Vis spectrum of them and prevents an unfavorable blue shift. Overall, the results point to an improved performance for DSC operation and development.

  6. Protection of pigs against pandemic swine origin H1N1 influenza A virus infection by hemagglutinin- or neuraminidase-expressing attenuated pseudorabies virus recombinants.

    Science.gov (United States)

    Klingbeil, Katharina; Lange, Elke; Blohm, Ulrike; Teifke, Jens P; Mettenleiter, Thomas C; Fuchs, Walter

    2015-03-01

    Influenza is an important respiratory disease of pigs, and may lead to novel human pathogens like the 2009 pandemic H1N1 swine-origin influenza virus (SoIV). Therefore, improved influenza vaccines for pigs are required. Recently, we demonstrated that single intranasal immunization with a hemagglutinin (HA)-expressing pseudorabies virus recombinant of vaccine strain Bartha (PrV-Ba) protected pigs from H1N1 SoIV challenge (Klingbeil et al., 2014). Now we investigated enhancement of efficacy by prime-boost vaccination and/or intramuscular administration. Furthermore, a novel PrV-Ba recombinant expressing codon-optimized N1 neuraminidase (NA) was included. In vitro replication of this virus was only slightly affected compared to parental virus. Unlike HA, the abundantly expressed NA was efficiently incorporated into PrV particles. Immunization of pigs with the two PrV recombinants, either singly or in combination, induced B cell proliferation and the expected SoIV-specific antibodies, whose titers increased substantially after boost vaccination. After immunization of animals with either PrV recombinant H1N1 SoIV challenge virus replication was significantly reduced compared to PrV-Ba vaccinated or naïve controls. Protective efficacy of HA-expressing PrV was higher than of NA-expressing PrV, and not significantly enhanced by combination. Despite higher serum antibody titers obtained after intramuscular immunization, transmission of challenge virus to naïve contact animals was only prevented after intranasal prime-boost vaccination with HA-expressing PrV-Ba.

  7. Oncolytic adenovirus-mediated therapy for prostate cancer

    Science.gov (United States)

    Sweeney, Katrina; Halldén, Gunnel

    2016-01-01

    Prostate cancer is a leading cause of cancer-related death and morbidity in men in the Western world. Tumor progression is dependent on functioning androgen receptor signaling, and initial administration of antiandrogens and hormone therapy (androgen-deprivation therapy) prevent growth and spread. Tumors frequently develop escape mechanisms to androgen-deprivation therapy and progress to castration-resistant late-stage metastatic disease that, in turn, inevitably leads to resistance to all current therapeutics, including chemotherapy. In spite of the recent development of more effective inhibitors of androgen–androgen receptor signaling such as enzalutamide and abiraterone, patient survival benefits are still limited. Oncolytic adenoviruses have proven efficacy in prostate cancer cells and cause regression of tumors in preclinical models of numerous drug-resistant cancers. Data from clinical trials demonstrate that adenoviral mutants have limited toxicity to normal tissues and are safe when administered to patients with various solid cancers, including prostate cancer. While efficacy in response to adenovirus administration alone is marginal, findings from early-phase trials targeting local-ized and metastatic prostate cancer suggest improved efficacy in combination with cytotoxic drugs and radiation therapy. Here, we review recent progress in the development of multimodal oncolytic adenoviruses as biological therapeutics to improve on tumor elimination in prostate cancer patients. These optimized mutants target cancer cells by several mechanisms including viral lysis and by expression of cytotoxic transgenes and immune-stimulatory factors that activate the host immune system to destroy both infected and noninfected prostate cancer cells. Additional modifications of the viral capsid proteins may support future systemic delivery of oncolytic adenoviruses. PMID:27579296

  8. Complex spatial dynamics of oncolytic viruses in vitro: mathematical and experimental approaches.

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    Dominik Wodarz

    Full Text Available Oncolytic viruses replicate selectively in tumor cells and can serve as targeted treatment agents. While promising results have been observed in clinical trials, consistent success of therapy remains elusive. The dynamics of virus spread through tumor cell populations has been studied both experimentally and computationally. However, a basic understanding of the principles underlying virus spread in spatially structured target cell populations has yet to be obtained. This paper studies such dynamics, using a newly constructed recombinant adenovirus type-5 (Ad5 that expresses enhanced jellyfish green fluorescent protein (EGFP, AdEGFPuci, and grows on human 293 embryonic kidney epithelial cells, allowing us to track cell numbers and spatial patterns over time. The cells are arranged in a two-dimensional setting and allow virus spread to occur only to target cells within the local neighborhood. Despite the simplicity of the setup, complex dynamics are observed. Experiments gave rise to three spatial patterns that we call "hollow ring structure", "filled ring structure", and "disperse pattern". An agent-based, stochastic computational model is used to simulate and interpret the experiments. The model can reproduce the experimentally observed patterns, and identifies key parameters that determine which pattern of virus growth arises. The model is further used to study the long-term outcome of the dynamics for the different growth patterns, and to investigate conditions under which the virus population eliminates the target cells. We find that both the filled ring structure and disperse pattern of initial expansion are indicative of treatment failure, where target cells persist in the long run. The hollow ring structure is associated with either target cell extinction or low-level persistence, both of which can be viewed as treatment success. Interestingly, it is found that equilibrium properties of ordinary differential equations describing the

  9. Pediatric glioma stem cells: biologic strategies for oncolytic HSV virotherapy

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    Gregory K Friedman

    2013-02-01

    Full Text Available While glioblastoma multiforme (GBM is the most common adult malignant brain tumor, GBMs in childhood represent less than 10% of pediatric malignant brain tumors and are phenotypically and molecularly distinct from adult GBMs. Similar to adult patients, outcomes for children with high-grade gliomas (HGGs remain poor. Furthermore, the significant morbidity and mortality yielded by pediatric GBM is compounded by neurotoxicity for the developing brain caused by current therapies. Poor outcomes have been attributed to a subpopulation of chemotherapy and radiotherapy resistant cells, termed ‘glioma stem cells’ (GSCs, ‘glioma progenitor cells’, or ‘glioma-initiating cells', which have the ability to initiate and maintain the tumor and to repopulate the recurring tumor after conventional therapy. Future innovative therapies for pediatric HGGs must be able to eradicate these therapy-resistant GSCs. Oncolytic herpes simplex viruses, genetically engineered to be safe for normal cells and to express diverse foreign anti-tumor therapeutic genes, have been demonstrated in preclinical studies to infect and kill GSCs and tumor cells equally while sparing normal brain cells. In this review, we discuss the unique aspects of pediatric GSCs, including markers to identify them, the microenvironment they reside in, signaling pathways that regulate them, mechanisms of cellular resistance, and approaches to target GSCs, with a focus on the promising therapeutic, genetically engineered oncolytic herpes simplex virus (HSV.

  10. ONCOLYTIC VIRUS-MEDIATED REVERSAL OF IMPAIRED TUMOR ANTIGEN PRESENTATION

    Directory of Open Access Journals (Sweden)

    Shashi Ashok Gujar

    2014-04-01

    Full Text Available Anti-tumor immunity can eliminate existing cancer cells and also maintain a constant surveillance against possible relapse. Such an antigen-specific adaptive response begins when tumor-specific T cells become activated. T cell activation requires two signals on antigen presenting cells (APCs: antigen presentation through MHC molecules and co-stimulation. In the absence of one or both of these signals, T cells remain inactivated or can even become tolerized. Cancer cells and their associated microenvironment strategically hinder the processing and presentation of tumor antigens and consequently prevent the development of anti-tumor immunity. Many studies, however, demonstrate that interventions that overturn tumor-associated immune evasion mechanisms can establish anti-tumor immune responses of therapeutic potential. One such intervention is oncolytic virus (OV-based anti-cancer therapy. Here we discuss how OV-induced immunological events override tumor-associated antigen presentation impairment and promote appropriate T cell:APC interaction. Detailed understanding of this phenomenon is pivotal for devising the strategies that will enhance the efficacy of OV-based anti-cancer therapy by complementing its inherent oncolytic

  11. Chronic Activation of Innate Immunity Correlates With Poor Prognosis in Cancer Patients Treated With Oncolytic Adenovirus.

    Science.gov (United States)

    Taipale, Kristian; Liikanen, Ilkka; Juhila, Juuso; Turkki, Riku; Tähtinen, Siri; Kankainen, Matti; Vassilev, Lotta; Ristimäki, Ari; Koski, Anniina; Kanerva, Anna; Diaconu, Iulia; Cerullo, Vincenzo; Vähä-Koskela, Markus; Oksanen, Minna; Linder, Nina; Joensuu, Timo; Lundin, Johan; Hemminki, Akseli

    2016-02-01

    Despite many clinical trials conducted with oncolytic viruses, the exact tumor-level mechanisms affecting therapeutic efficacy have not been established. Currently there are no biomarkers available that would predict the clinical outcome to any oncolytic virus. To assess the baseline immunological phenotype and find potential prognostic biomarkers, we monitored mRNA expression levels in 31 tumor biopsy or fluid samples from 27 patients treated with oncolytic adenovirus. Additionally, protein expression was studied from 19 biopsies using immunohistochemical staining. We found highly significant changes in several signaling pathways and genes associated with immune responses, such as B-cell receptor signaling (P immunity before treatment is associated with inferior survival in patients treated with oncolytic adenovirus. Conversely, lack of chronic innate inflammation at baseline may predict improved treatment outcome, as suggested by good overall prognosis.

  12. Oncolytic effects of a novel influenza A virus expressing interleukin-15 from the NS reading frame.

    Directory of Open Access Journals (Sweden)

    Marijke van Rikxoort

    Full Text Available Oncolytic influenza A viruses with deleted NS1 gene (delNS1 replicate selectively in tumour cells with defective interferon response and/or activated Ras/Raf/MEK/ERK signalling pathway. To develop a delNS1 virus with specific immunostimulatory properties, we used an optimised technology to insert the interleukin-15 (IL-15 coding sequence into the viral NS gene segment (delNS1-IL-15. DelNS1 and delNS1-IL-15 exerted similar oncolytic effects. Both viruses replicated and caused caspase-dependent apoptosis in interferon-defective melanoma cells. Virus replication was required for their oncolytic activity. Cisplatin enhanced the oncolytic activity of delNS1 viruses. The cytotoxic drug increased delNS1 replication and delNS1-induced caspase-dependent apoptosis. Interference with MEK/ERK signalling by RNAi-mediated depletion or the MEK inhibitor U0126 did not affect the oncolytic effects of the delNS1 viruses. In oncolysis sensitive melanoma cells, delNS1-IL-15 (but not delNS1 infection resulted in the production of IL-15 levels ranging from 70 to 1140 pg/mL in the cell culture supernatants. The supernatants of delNS1-IL-15-infected (but not of delNS1-infected melanoma cells induced primary human natural killer cell-mediated lysis of non-infected tumour cells. In conclusion, we constructed a novel oncolytic influenza virus that combines the oncolytic activity of delNS1 viruses with immunostimulatory properties through production of functional IL-15. Moreover, we showed that the oncolytic activity of delNS1 viruses can be enhanced in combination with cytotoxic anti-cancer drugs.

  13. Inhibition of Dual Specific Oncolytic Adenovirus on Esophageal Cancer via Activation of Caspases by a Mitochondrial-dependent Pathway

    Institute of Scientific and Technical Information of China (English)

    SU Jia-qiang; CHI Bao-rong; LI Xiao; LIU Lei; LIU Li-ming; QI Yan-xin; WANG Zhuo-yue; JIN Ning-yi

    2012-01-01

    We investigated the anti-tumor effects of dual cancer specific-oncolytic adenovirus Ad-VP on esophageal cancer(EC).The anti-tumor activity of Ad-VP was compared with that of the control recombinant adenoviruses (Ad-GP,Ad-Apoptin,Ad-EGFP) in human esophageal cancer cell EC-109 and human normal liver cell L02 in vitro.In 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assays,the growth of EC-109 cells was slightly inhibited by Ad-GP.Ad-Apoptin and Ad-EGFP.However,Ad-VP induced a significant cytotoxic effect.Infection of EC-109 cells with Ad-VP resulted in a significant induction of apoptosis of them in vitro,detected by 4′,6-diamidino-2-phenylindole(DAPI) or acridine orange and ethidium bromide staining.The results of Western blot and flow cytometric assay indicate the loss of mitochondrial membrane potential(△ψm),the release of cytochrome c and the activation of caspase-3,6 and 7 in Ad-VP infiected EC-109 cells.In contrast,all these assays show almost no effects of the recombinant adenoviruses on L02 cells.These results demonstrate that the treatment of tumors with Ad-VP selectively inhibits tumor growth and induces apoptosis of esophageal cancer cells.Ad-VP may provide a novel and powerful strategy for cancer gene therapy.

  14. Questing for an optimal, universal viral agent for oncolytic virotherapy

    CERN Document Server

    Paiva, L R; Ferreira, S C

    2011-01-01

    One of the most promising strategies to treat cancer is attacking it with viruses designed to exploit specific altered pathways. Here, the effects of oncolytic virotherapy on tumors having compact, papillary and disconnected morphologies are investigated through computer simulations of a multiscale model coupling macroscopic reaction diffusion equations for the nutrients with microscopic stochastic rules for the actions of individual cells and viruses. The interaction among viruses and tumor cells involves cell infection, intracellular virus replication and release of new viruses in the tissue after cell lysis. The evolution in time of both viral load and cancer cell population, as well as the probabilities for tumor eradication were evaluated for a range of multiplicities of infection, viral entries and burst sizes. It was found that in immunosuppressed hosts, the antitumor efficacy of a virus is primarily determined by its entry efficiency, its replicative capacity within the tumor, and its ability to sprea...

  15. High-throughput screening to enhance oncolytic virus immunotherapy

    Directory of Open Access Journals (Sweden)

    Allan KJ

    2016-04-01

    Full Text Available KJ Allan,1,2 David F Stojdl,1–3 SL Swift1 1Children’s Hospital of Eastern Ontario (CHEO Research Institute, 2Department of Biology, Microbiology and Immunology, 3Department of Pediatrics, University of Ottawa, Ottawa, ON, Canada Abstract: High-throughput screens can rapidly scan and capture large amounts of information across multiple biological parameters. Although many screens have been designed to uncover potential new therapeutic targets capable of crippling viruses that cause disease, there have been relatively few directed at improving the efficacy of viruses that are used to treat disease. Oncolytic viruses (OVs are biotherapeutic agents with an inherent specificity for treating malignant disease. Certain OV platforms – including those based on herpes simplex virus, reovirus, and vaccinia virus – have shown success against solid tumors in advanced clinical trials. Yet, many of these OVs have only undergone minimal engineering to solidify tumor specificity, with few extra modifications to manipulate additional factors. Several aspects of the interaction between an OV and a tumor-bearing host have clear value as targets to improve therapeutic outcomes. At the virus level, these include delivery to the tumor, infectivity, productivity, oncolysis, bystander killing, spread, and persistence. At the host level, these include engaging the immune system and manipulating the tumor microenvironment. Here, we review the chemical- and genome-based high-throughput screens that have been performed to manipulate such parameters during OV infection and analyze their impact on therapeutic efficacy. We further explore emerging themes that represent key areas of focus for future research. Keywords: oncolytic, virus, screen, high-throughput, cancer, chemical, genomic, immunotherapy

  16. Stem Cell-Based Cell Carrier for Targeted Oncolytic Virotherapy: Translational Opportunity and Open Questions.

    Science.gov (United States)

    Kim, Janice; Hall, Robert R; Lesniak, Maciej S; Ahmed, Atique U

    2015-11-27

    Oncolytic virotherapy for cancer is an innovative therapeutic option where the ability of a virus to promote cell lysis is harnessed and reprogrammed to selectively destroy cancer cells. Such treatment modalities exhibited antitumor activity in preclinical and clinical settings and appear to be well tolerated when tested in clinical trials. However, the clinical success of oncolytic virotherapy has been significantly hampered due to the inability to target systematic metastasis. This is partly due to the inability of the therapeutic virus to survive in the patient circulation, in order to target tumors at distant sites. An early study from various laboratories demonstrated that cells infected with oncolytic virus can protect the therapeutic payload form the host immune system as well as function as factories for virus production and enhance the therapeutic efficacy of oncolytic virus. While a variety of cell lineages possessed potential as cell carriers, copious investigation has established stem cells as a very attractive cell carrier system in oncolytic virotherapy. The ideal cell carrier desire to be susceptible to viral infection as well as support viral infection, maintain immunosuppressive properties to shield the loaded viruses from the host immune system, and most importantly possess an intrinsic tumor homing ability to deliver loaded viruses directly to the site of the metastasis-all qualities stem cells exhibit. In this review, we summarize the recent work in the development of stem cell-based carrier for oncolytic virotherapy, discuss the advantages and disadvantages of a variety of cell carriers, especially focusing on why stem cells have emerged as the leading candidate, and finally propose a future direction for stem cell-based targeted oncolytic virotherapy that involves its establishment as a viable treatment option for cancer patients in the clinical setting.

  17. Recombinant osteopontin attenuates hyperoxia-induced acute lung injury through inhibiting nuclear factor kappa B and matrix metalloproteinases 2 and 9

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiangfeng; Liu Fen; Zhu Guangfa; Wang Zengzhi

    2014-01-01

    Background Exposure of adult mice to more than 95% O2 produces a lethal injury by 72 hours.Nuclear factor kappa B (NF-κB) is a transcriptional factor that plays a key role in the modulation of cytokine networks during hyperoxia-induced acute lung injury (ALl).Osteopontin (OPN) is a phosphorylated glycoprotein produced principally by macrophages.Studies have reported that exogenous OPN can maintain the integrity of the cerebral microvascular basement membrane and reduce brain damage through inhibiting NF-κB activities in the brain after subarachnoid hemorrhage.However,it is not clear whether OPN can reduce lung injury during ALl by inhibiting transcriptional signal pathways of NF-κB and consequent inhibition of infiammatory cytokines.Thus we examined the effects and mechanisms of recombinant OPN (r-OPN) on ALl.Methods Ninety-six mice were randomly divided into phosphate buffered saline (PBS) and r-OPN groups.Mice were put in an oxygen chamber (>95% O2) and assessed for lung injury at 24,48,and 72 hours.Expressions of NF-κB,matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9),and tissue inhibitors of MMP-2 and MMP-9 (TIMP-1,TIMP-2) mRNA in lungs were examined with RT-PCR.Expression and distribution of NF-κB protein in lungs were measured with immunohistochemistry.Results Exposure to hyperoxia for 72 hours induced more severe lung injury in the PBS group compared with the r-OPN group.Expression of NF-κB mRNA in the PBS group exposed to hyperoxia for 48 and 72 hours was significantly higher than the r-OPN group (P <0.05).With 72-hour exposure,expression of TIMP-1 mRNA in the r-OPN group was significantly higher than that of the PBS group (P <0.05).Expression of TIMP-2 mRNA in the r-OPN group at 48 and 72 hours was significantly higher than those in the PBS group (P <0.05).After 72-hour exposure,expression of NF-κB protein in airway epithelium in the PBS group was significantly higher than that in the r-OPN group (P <0.05).Conclusion r-OPN can

  18. Chemotherapy and Oncolytic Virotherapy: Advanced Tactics in the War against Cancer

    Directory of Open Access Journals (Sweden)

    Andrew eNguyen

    2014-06-01

    Full Text Available Cancer is a traitorous archenemy that threatens our survival. Its ability to evade detection and adapt to various cancer therapies means that it is a moving target that becomes increasingly difficult to attack. Through technological advancements we have developed sophisticated weapons to fight off tumor growth and invasion. However, if we are to stand a chance in this war against cancer, advanced tactics will be required to maximize the use of our available resources. Oncolytic viruses are multi-functional cancer-fighters that can be engineered to suit many different strategies; in particular, their retooling can facilitate increased capacity for direct tumor killing (oncolytic virotherapy and elicit adaptive antitumor immune responses (oncolytic immunotherapy. However, administration of these modified oncolytic viruses alone, rarely induces successful regression of established tumors. This may be attributed to host antiviral immunity that acts to eliminate viral particles, as well as the capacity for tumors to adapt to therapeutic selective pressure. It has been shown that various chemotherapeutic drugs with distinct functional properties can potentiate the antitumor efficacy of oncolytic viruses. In this review, we summarize the chemotherapeutic combinatorial strategies used to optimize virally-induced destruction of tumors. With a particular focus on pharmaceutical immunomodulators, we discuss how specific therapeutic contexts may alter the effects of these synergistic combinations and their implications for future clinical use.

  19. [Oncolytic viruses as a new way of treatment of neoplastic diseases].

    Science.gov (United States)

    Kukla, Urszula; Chronowska, Justyna; Łabuzek, Krzysztof; Okopień, Bogusław

    2015-08-01

    Despite the unceasing progression in chemotherapy, radiotherapy and surgery, neoplasms are still the second, after cardiovascular diseases, cause of death in the world. The creation of oncolytic viruses gives hope for increase of anticancer therapy effectiveness. Oncolytic viruses are the type of viruses that selectively infect and cause the lyse of tumor cells excluding normal cells. This mechanism allows to avoid the consequences of the possible replication of the virus, which having entered to the organism, replicates in organism's cells by using the DNA of host cells. The development of genetic engineering and molecular biology has enabled the creation of this kind of genetically modified viruses, which deprive them of their virulence. Currently, there are many clinical trials in progress including the use of oncolytic viruses in head and neck squamous cell carcinoma, thyroid cancer, colorectal cancer, liver cancer, melanoma and glioblastoma multiforme treatment. There are parallel studies in animals using the subsequent viruses. Oncolytic viruses treatment is generally well tolerated, without significant side effects. It is worth to point out that this method combined with chemotherapy and radiotherapy allows to reduce the use of therapeutic doses, which significantly reduces the toxicity of conventional treatment. Further clinical studies evaluating the efficacy and safety of oncolytic viruses will develop more effective and better tolerated therapeutic protocols in the future.

  20. Effects of nanoparticle coatings on the activity of oncolytic adenovirus-magnetic nanoparticle complexes.

    Science.gov (United States)

    Tresilwised, Nittaya; Pithayanukul, Pimolpan; Holm, Per Sonne; Schillinger, Ulrike; Plank, Christian; Mykhaylyk, Olga

    2012-01-01

    Limitations to adenovirus infectivity can be overcome by association with magnetic nanoparticles and enforced infection by magnetic field influence. Here we examined three core-shell-type iron oxide magnetic nanoparticles differing in their surface coatings, particle sizes and magnetic properties for their ability to enhance the oncolytic potency of adenovirus Ad520 and to stabilize it against the inhibitory effects of serum or a neutralizing antibody. It was found that the physicochemical properties of magnetic nanoparticles are critical determinants of the properties which govern the oncolytic productivities of their complexes with Ad520. Although high serum concentration during infection or a neutralizing antibody had strong inhibitory influence on the uptake or oncolytic productivity of the naked virus, one particle type was identified which conferred high protection against both inhibitory factors while enhancing the oncolytic productivity of the internalized virus. This particle type equipped with a silica coating and adsorbed polyethylenimine, displaying a high magnetic moment and high saturation magnetization, mediated a 50% reduction of tumor growth rate versus control upon intratumoral injection of its complex with Ad520 and magnetic field influence, whereas Ad520 alone was inefficient. The correlations between physical properties of the magnetic particles or virus complexes and oncolytic potency are described herein.

  1. Changing faces in virology: the dutch shift from oncogenic to oncolytic viruses.

    Science.gov (United States)

    Belcaid, Zineb; Lamfers, Martine L M; van Beusechem, Victor W; Hoeben, Rob C

    2014-10-01

    Viruses have two opposing faces. On the one hand, they can cause harm and disease. A virus may manifest directly as a contagious disease with a clinical pathology of varying significance. A viral infection can also have delayed consequences, and in rare cases may cause cellular transformation and cancer. On the other hand, viruses may provide hope: hope for an efficacious treatment of serious disease. Examples of the latter are the use of viruses as a vaccine, as transfer vector for therapeutic genes in a gene therapy setting, or, more directly, as therapeutic anticancer agent in an oncolytic-virus therapy setting. Already there is evidence for antitumor activity of oncolytic viruses. The antitumor efficacy seems linked to their capacity to induce a tumor-directed immune response. Here, we will provide an overview on the development of oncolytic viruses and their clinical evaluation from the Dutch perspective.

  2. Ultrasound-mediated oncolytic virus delivery and uptake for increased therapeutic efficacy: state of art

    Directory of Open Access Journals (Sweden)

    Nande R

    2015-11-01

    Full Text Available Rounak Nande,1 Candace M Howard,2 Pier Paolo Claudio,3,4 1Department of Biochemistry and Microbiology, Marshall University School of Medicine, Huntington, WV, 2Department of Radiology, University of Mississippi Medical Center, Jackson, MS, 3Department of BioMolecular Sciences and National Center for Natural Products Research, School of Pharmacy, University of Mississippi, MS, 4Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS, USA Abstract: The field of ultrasound (US has changed significantly from medical imaging and diagnosis to treatment strategies. US contrast agents or microbubbles (MB are currently being used as potential carriers for chemodrugs, small molecules, nucleic acids, small interfering ribonucleic acid, proteins, adenoviruses, and oncolytic viruses. Oncolytic viruses can selectively replicate within and destroy a cancer cell, thus making them a powerful therapeutic in treating late-stage or metastatic cancer. These viruses have been shown to have robust activity in clinical trials when injected directly into tumor nodules. However limitations in oncolytic virus’ effectiveness and its delivery approach have warranted exploration of ultrasound-mediated delivery. Gene therapy bearing adenoviruses or oncolytic viruses can be coupled with MBs and injected intravenously. Following application of US energy to the target region, the MBs cavitate, and the resulting shock wave enhances drug, gene, or adenovirus uptake. Though the underlying mechanism is yet to be fully understood, there is evidence to suggest that mechanical pore formation of cellular membranes allows for the temporary uptake of drugs. This delivery method circumvents the limitations due to stimulation of the immune system that prevented intravenous administration of viruses. This review provides insight into this intriguing new frontier on the delivery of oncolytic viruses to tumor sites.Keywords: microbubbles, ultrasound

  3. Oncolytic viruses: From bench to bedside with a focus on safety

    Science.gov (United States)

    Buijs, Pascal RA; Verhagen, Judith HE; van Eijck, Casper HJ; van den Hoogen, Bernadette G

    2015-01-01

    Oncolytic viruses are a relatively new class of anti-cancer immunotherapy agents. Several viruses have undergone evaluation in clinical trials in the last decades, and the first agent is about to be approved to be used as a novel cancer therapy modality. In the current review, an overview is presented on recent (pre)clinical developments in the field of oncolytic viruses that have previously been or currently are being evaluated in clinical trials. Special attention is given to possible safety issues like toxicity, environmental shedding, mutation and reversion to wildtype virus. PMID:25996182

  4. High-throughput screening to enhance oncolytic virus immunotherapy

    Science.gov (United States)

    Allan, KJ; Stojdl, David F; Swift, SL

    2016-01-01

    High-throughput screens can rapidly scan and capture large amounts of information across multiple biological parameters. Although many screens have been designed to uncover potential new therapeutic targets capable of crippling viruses that cause disease, there have been relatively few directed at improving the efficacy of viruses that are used to treat disease. Oncolytic viruses (OVs) are biotherapeutic agents with an inherent specificity for treating malignant disease. Certain OV platforms – including those based on herpes simplex virus, reovirus, and vaccinia virus – have shown success against solid tumors in advanced clinical trials. Yet, many of these OVs have only undergone minimal engineering to solidify tumor specificity, with few extra modifications to manipulate additional factors. Several aspects of the interaction between an OV and a tumor-bearing host have clear value as targets to improve therapeutic outcomes. At the virus level, these include delivery to the tumor, infectivity, productivity, oncolysis, bystander killing, spread, and persistence. At the host level, these include engaging the immune system and manipulating the tumor microenvironment. Here, we review the chemical- and genome-based high-throughput screens that have been performed to manipulate such parameters during OV infection and analyze their impact on therapeutic efficacy. We further explore emerging themes that represent key areas of focus for future research. PMID:27579293

  5. Oncolytic parvoviruses: from basic virology to clinical applications.

    Science.gov (United States)

    Marchini, Antonio; Bonifati, Serena; Scott, Eleanor M; Angelova, Assia L; Rommelaere, Jean

    2015-01-29

    Accumulated evidence gathered over recent decades demonstrated that some members of the Parvoviridae family, in particular the rodent protoparvoviruses H-1PV, the minute virus of mice and LuIII have natural anticancer activity while being nonpathogenic to humans. These studies have laid the foundations for the launch of a first phase I/IIa clinical trial, in which the rat H-1 parvovirus is presently undergoing evaluation for its safety and first signs of efficacy in patients with glioblastoma multiforme. After a brief overview of the biology of parvoviruses, this review focuses on the studies which unraveled the antineoplastic properties of these agents and supported their clinical use as anticancer therapeutics. Furthermore, the development of novel parvovirus-based anticancer strategies with enhanced specificity and efficacy is discussed, in particular the development of second and third generation vectors and the combination of parvoviruses with other anticancer agents. Lastly, we address the key challenges that remain towards a more rational and efficient use of oncolytic parvoviruses in clinical settings, and discuss how a better understanding of the virus life-cycle and of the cellular factors involved in virus infection, replication and cytotoxicity may promote the further development of parvovirus-based anticancer therapies, open new prospects for treatment and hopefully improve clinical outcome.

  6. Construction and identification of a recombinant attenuated Salmonella typhimurium vaccine strain expressing Helicobacter pylori hpaA gene%表达幽门螺杆菌hpaA重组减毒鼠伤寒沙门氏菌的构建和鉴定

    Institute of Scientific and Technical Information of China (English)

    朱森林; 陈旻湖; 廖文俊; 陈洁; 胡品津

    2001-01-01

    Objective: To construct a recombinant live attenuated Salmonellaty phimurium vaccine strain expressing Helicobacter pylori hpaA gene.Methods: By g enetic engineering methods,hpaA gene was cloned into a procaryotic expression pl asmid pTrc99A,and the identified recombinant plasmid was then used to transform an attenuated Salmonella typhimurium vaccine strain SL3261,and the positive clon es were screened by PCR and restriction enzyme digestion. HpaA expression was an alyzed by SDS-PAGE and Western blot.Results:Confirmed by PCR and restriction en zyme digestion ,a recombinant procaryotic expression plasmid pTrc99A-hpaA was c o nstructed,and then introduced into an attenuated Sa lmonella typhimurium vaccine strain SL3261 successfully. HpaA was expressed in t he recombinant strains in the form of a dimer,and also its immunogenicity was co nfirmed by Western blot. Conclusion: A recombinant live attenuated Salmonella ty phimurium vaccine strain expressing Helicobacter pylori hpaA gene was constructe d and identified,and this work will help to develop an oral recombinant live vac cine against Helicobacter pylori.%目的:构建表达幽门螺杆菌(H.pylori)hpaA的重组减毒鼠伤寒沙门氏疫苗菌。方法:用基因工程的方法将hpaA基因克隆入原核表达质粒pTrc99A,并进行了基因测序。重组质粒经鉴定后再导入减毒鼠伤寒沙门氏菌SL3261,提取重组疫苗菌质粒,PCR和酶切鉴定,筛选阳性克隆。用SDS-PAGE电泳和Westernblot进行HpaA表达和鉴定。结果:经PCR和酶切证实,构建了含hpaA的重组原核表达质粒pTrc99A-hpaA,并将后者成功转化了减毒鼠伤寒沙门氏菌。HpaA能在疫苗菌中以二聚体形式表达,HpaA量约占全菌体蛋白量的17%,Westernblot证实其有免疫原性。结论:构建了表达H.pylorihpaA的重组减毒鼠伤寒沙门氏疫苗菌,为探索制备H.pylori口服活疫苗奠定了基础。

  7. The immunoregulatory properties of oncolytic myxoma virus and their implications in therapeutics.

    Science.gov (United States)

    Liu, Jia; Wennier, Sonia; McFadden, Grant

    2010-12-01

    Myxoma virus (MYXV) is a poxvirus with a strict rabbit-specific host-tropism for pathogenesis. The immunoregulatory factors encoded by MYXV can suppress some functions of immune effectors from other species. We review their mechanisms of action, implications in therapeutics and the potential to improve MYXV as an oncolytic agent in humans.

  8. The immunoregulatory properties of oncolytic myxoma virus and their implications in therapeutics

    OpenAIRE

    Liu, Jia; Wennier, Sonia; McFadden, Grant

    2010-01-01

    Myxoma virus (MYXV) is a poxvirus with a strict rabbit-specific host-tropism for pathogenesis. The immunoregulatory factors encoded by MYXV can suppress some functions of immune effectors from other species. We review their mechanisms of action, implications in therapeutics and the potential to improve MYXV as an oncolytic agent in humans.

  9. Oncolytic viral purging of leukemic hematopoietic stem and progenitor cells with Myxoma virus.

    Science.gov (United States)

    Rahman, Masmudur M; Madlambayan, Gerard J; Cogle, Christopher R; McFadden, Grant

    2010-01-01

    High-dose chemotherapy and radiation followed by autologous blood and marrow transplantation (ABMT) has been used for the treatment of certain cancers that are refractory to standard therapeutic regimes. However, a major challenge with ABMT for patients with hematologic malignancies is disease relapse, mainly due to either contamination with cancerous hematopoietic stem and progenitor cells (HSPCs) within the autograft or the persistence of residual therapy-resistant disease niches within the patient. Oncolytic viruses represent a promising therapeutic approach to prevent cancer relapse by eliminating tumor-initiating cells that contaminate the autograft. Here we summarize an ex vivo "purging" strategy with oncolytic Myxoma virus (MYXV) to remove cancer-initiating cells from patient autografts prior to transplantation. MYXV, a novel oncolytic poxvirus with potent anti-cancer properties in a variety of in vivo tumor models, can specifically eliminate cancerous stem and progenitor cells from samples obtained from acute myelogenous leukemia (AML) patients, while sparing normal CD34+ hematopoietic stem and progenitor cells capable of rescuing hematopoiesis following high dose conditioning. We propose that a broader subset of patients with intractable hematologic malignancies who have failed standard therapy could become eligible for ABMT when the treatment schema is coupled with ex vivo oncolytic therapy.

  10. The ex vivo purge of cancer cells using oncolytic viruses: recent advances and clinical implications

    Directory of Open Access Journals (Sweden)

    Tsang JJ

    2015-01-01

    Full Text Available Jovian J Tsang,1,2 Harold L Atkins2,3 1Department of Biochemistry, University of Ottawa, 2Cancer Therapeutics, Ottawa Hospital Research Institute, 3Blood and Marrow Transplant Program, The Ottawa Hospital, Ottawa, ON, Canada Abstract: Hematological malignancies are treated with intensive high-dose chemotherapy, with or without radiation. This is followed by hematopoietic stem cell (HSC transplantation (HSCT to rescue or reconstitute hematopoiesis damaged by the anticancer therapy. Autologous HSC grafts may contain cancer cells and purging could further improve treatment outcomes. Similarly, allogeneic HSCT may be improved by selectively purging alloreactive effector cells from the graft rather than wholesale immune cell depletion. Viral agents that selectively replicate in specific cell populations are being studied in experimental models of cancer and immunological diseases and have potential applications in the context of HSC graft engineering. This review describes preclinical studies involving oncolytic virus strains of adenovirus, herpes simplex virus type 1, myxoma virus, and reovirus as ex vivo purging agents for HSC grafts, as well as in vitro and in vivo experimental studies using oncolytic coxsackievirus, measles virus, parvovirus, vaccinia virus, and vesicular stomatitis virus to eradicate hematopoietic malignancies. Alternative ex vivo oncolytic virus strategies are also outlined that aim to reduce the risk of relapse following autologous HSCT and mitigate morbidity and mortality due to graft-versus-host disease in allogeneic HSCT. Keywords: hematopoietic stem cells, oncolytic virus, hematopoietic stem cell transplantation, stem cell graft purging, hematopoietic malignancy, graft vs host disease

  11. Immunosuppression enhances oncolytic adenovirus replication and antitumor efficacy in the Syrian hamster model.

    Science.gov (United States)

    Thomas, Maria A; Spencer, Jacqueline F; Toth, Karoly; Sagartz, John E; Phillips, Nancy J; Wold, William S M

    2008-10-01

    We recently described an immunocompetent Syrian hamster model for oncolytic adenoviruses (Ads) that permits virus replication in tumor cells as well as some normal tissues. This model allows exploration of interactions between the virus, tumor, normal organs, and host immune system that could not be examined in the immunodeficient or nonpermissive animal models previously used in the oncolytic Ad field. Here we asked whether the immune response to oncolytic Ad enhances or limits antitumor efficacy. We first determined that cyclophosphamide (CP) is a potent immunosuppressive agent in the Syrian hamster and that CP alone had no effect on tumor growth. Importantly, we found that the antitumor efficacy of oncolytic Ads was significantly enhanced in immunosuppressed animals. In animals that received virus therapy plus immunosuppression, significant differences were observed in tumor histology, and in many cases little viable tumor remained. Notably, we also determined that immunosuppression allowed intratumoral virus levels to remain elevated for prolonged periods. Although favorable tumor responses can be achieved in immunocompetent animals, the rate of virus clearance from the tumor may lead to varied antitumor efficacy. Immunosuppression, therefore, allows sustained Ad replication and oncolysis, which leads to substantially improved suppression of tumor growth.

  12. Effect of Repeat Dosing of Engineered Oncolytic Herpes Simplex Virus on Preclinical Models of Rhabdomyosarcoma

    Directory of Open Access Journals (Sweden)

    Alicia M. Waters

    2016-10-01

    Full Text Available Rhabdomyosarcoma (RMS, a tumor of skeletal muscle origin, is the most common sarcoma of childhood. Despite multidrug chemotherapy regimens, surgical intervention, and radiation treatment, outcomes remain poor, especially in advanced disease, and novel therapies are needed for the treatment of these aggressive malignancies. Genetically engineered oncolytic viruses, such as herpes simplex virus-1 (HSV, are currently being explored as treatments for pediatric tumors. M002, an oncolytic HSV, has both copies of the γ134.5 gene deleted, enabling replication in tumor cells but thwarting infection of normal, postmitotic cells. We hypothesized that M002 would infect human RMS tumor cells and lead to decreased tumor cell survival in vitro and impede tumor growth in vivo. In the current study, we demonstrated that M002 could infect, replicate in, and decrease cell survival in both embryonal (ERMS and alveolar rhabdomyosarcoma (ARMS cells. Additionally, M002 reduced xenograft tumor growth and increased animal survival in both ARMS and ERMS. Most importantly, we showed for the first time that repeated dosing of oncolytic virus coupled with low-dose radiation provided improved tumor response in RMS. These findings provide support for the clinical investigation of oncolytic HSV in pediatric RMS.

  13. Neuroblastoma cell lines contain pluripotent tumor initiating cells that are susceptible to a targeted oncolytic virus.

    Directory of Open Access Journals (Sweden)

    Yonatan Y Mahller

    Full Text Available BACKGROUND: Although disease remission can frequently be achieved for patients with neuroblastoma, relapse is common. The cancer stem cell theory suggests that rare tumorigenic cells, resistant to conventional therapy, are responsible for relapse. If true for neuroblastoma, improved cure rates may only be achieved via identification and therapeutic targeting of the neuroblastoma tumor initiating cell. Based on cues from normal stem cells, evidence for tumor populating progenitor cells has been found in a variety of cancers. METHODOLOGY/PRINCIPAL FINDINGS: Four of eight human neuroblastoma cell lines formed tumorspheres in neural stem cell media, and all contained some cells that expressed neurogenic stem cell markers including CD133, ABCG2, and nestin. Three lines tested could be induced into multi-lineage differentiation. LA-N-5 spheres were further studied and showed a verapamil-sensitive side population, relative resistance to doxorubicin, and CD133+ cells showed increased sphere formation and tumorigenicity. Oncolytic viruses, engineered to be clinically safe by genetic mutation, are emerging as next generation anticancer therapeutics. Because oncolytic viruses circumvent typical drug-resistance mechanisms, they may represent an effective therapy for chemotherapy-resistant tumor initiating cells. A Nestin-targeted oncolytic herpes simplex virus efficiently replicated within and killed neuroblastoma tumor initiating cells preventing their ability to form tumors in athymic nude mice. CONCLUSIONS/SIGNIFICANCE: These results suggest that human neuroblastoma contains tumor initiating cells that may be effectively targeted by an oncolytic virus.

  14. Oncolytic viruses as immunotherapy: progress and remaining challenges

    Directory of Open Access Journals (Sweden)

    Aurelian L

    2016-05-01

    Full Text Available Laure Aurelian Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD, USA Abstract: Oncolytic viruses (OVs comprise an emerging cancer therapeutic modality whose activity involves both direct tumor cell lysis and the induction of immunogenic cell death (ICD. Cellular proteins released from the OV-lysed tumor cells, known as damage-associated molecular patterns and tumor-associated antigens, activate dendritic cells and elicit adaptive antitumor immunity. Interaction with the innate immune system and the development of long-lasting immune memory also contribute to OV-induced cell death. The degree to which the ICD component contributes to the clinical efficacy of OV therapy is still unclear. Modulation of a range of immune interactions may be beneficial or detrimental in nature and the interactions depend on the specific tumor, the site and extent of the disease, the immunosuppressive tumor microenvironment, the OV platform, the dose, time, and delivery conditions, as well as individual patient responses. To enhance the contribution of ICD, OVs have been engineered to express immunostimulatory genes and strategies have been developed to combine OV therapy with chemo- and immune-based therapeutic regimens. However, these approaches carry the risk that they may also be tolerogenic depending on their levels and the presence of other cytokines, their direct antiviral effects, and the timing and conditions of their expression. The contribution of autophagy to adaptive immunity, the ability of the OVs to kill cancer stem cells, and the patient’s baseline immune status are additional considerations. This review focuses on the complex and as yet poorly understood balancing act that dictates the outcome of OV therapy. We summarize current understanding of the OVs’ function in eliciting antitumor immunity and its relationship to therapeutic efficacy. Also discussed are the criteria involved in restraining antiviral

  15. Heterogeneous delivery is a barrier to the translational advancement of oncolytic virotherapy for treating solid tumors

    Directory of Open Access Journals (Sweden)

    Miller AC

    2014-07-01

    Full Text Available Amber C Miller,1,2 Stephen J Russell2,3 1Mayo Graduate School, Mayo Clinic, Rochester, Minnesota, USA; 2Department of Molecular Medicine, Mayo Clinic, Rochester, Minnesota, USA; 3Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA Abstract: Oncolytic viruses are a promising experimental anticancer therapy currently undergoing clinical translation. The development of oncolytic virotherapy offers a potential solution to the elusive “one-shot”cancer cure by providing targeted therapy to selectively infect and kill cancer cells while provoking adaptive anticancer immune responses as protection against distant metastasis and recurrent tumor challenge. While this technology has overcome barriers to safety and efficacy through cancer-specific targeting techniques, in order to reach full therapeutic potential, oncolytic therapies must still overcome barriers to intratumoral delivery and spread that result in heterogeneous intratumoral delivery and nonuniform response. This review will discuss barriers to oncolytic virotherapy translation related to mechanisms of delivering virus via tumor vasculature and distributing virus throughout the tumor microenvironment. Barriers include extravasation into the tumor that is dependent on adequate blood flow, tissue perfusion, and tumoral enhanced permeability and retention for transvascular transport. Subsequently, virions must undergo interstitial transport against dense stromal barriers and high interstitial fluid pressure to initiate infection. In order to achieve massive tumor regression, infection must spread to cover large volumes of tumor mass. Furthermore, virus bioavailability is quickly dampened upon systemic administration due to neutralization and sequestration. These barriers to delivery limit the amount of virus that effectively reaches and spreads within the tumor, forcing dose increases that impinge upon limits of production and increase possibility of adverse

  16. Herpes simplex virus type-1(HSV-1 oncolytic and highly fusogenic mutants carrying the NV1020 genomic deletion effectively inhibit primary and metastatic tumors in mice

    Directory of Open Access Journals (Sweden)

    David Andrew T

    2008-06-01

    Full Text Available Abstract Background The NV1020 oncolytic herpes simplex virus type-1 has shown significant promise for the treatment of many different types of tumors in experimental animal models and human trials. Previously, we described the construction and use of the NV1020-like virus OncSyn to treat human breast tumors implanted in nude mice. The syncytial mutation gKsyn1 (Ala-to-Val at position 40 was introduced into the OncSyn viral genome cloned into a bacterial artificial chromosome using double-red mutagenesis in E. coli to produce the OncdSyn virus carrying syncytial mutations in both gB(syn3 and gK(syn1. Results The OncdSyn virus caused extensive virus-induced cell fusion in cell culture. The oncolytic potential of the OncSyn and OncdSyn viruses was tested in the highly metastatic syngeneic mouse model system, which utilizes 4T1 murine mammary cancer cells implanted within the interscapular region of Balb/c mice. Mice were given three consecutive intratumor injections of OncSyn, OncdSyn, or phosphate buffered saline four days apart. Both OncSyn and OncdSyn virus injections resulted in significant reduction of tumor sizes (p Conclusion These results show that the attenuated, but highly fusogenic OncSyn and OncdSyn viruses can effectively reduce primary and metastatic breast tumors in immuncompetent mice. The available bac-cloned OncSyn and OncdSyn viral genomes can be rapidly modified to express a number of different anti-tumor and immunomodulatory genes that can further enhance their anti-tumor potency.

  17. Replacement of the Ectodomains of the Hemagglutinin-Neuraminidase and Fusion Glycoproteins of Recombinant Parainfluenza Virus Type 3 (PIV3) with Their Counterparts from PIV2 Yields Attenuated PIV2 Vaccine Candidates

    OpenAIRE

    Tao, Tao; Skiadopoulos, Mario H.; Davoodi, Fatemeh; Riggs, Jeffrey M.; Collins, Peter L.; Murphy, Brian R

    2000-01-01

    We sought to develop a live attenuated parainfluenza virus type 2 (PIV2) vaccine strain for use in infants and young children, using reverse genetic techniques that previously were used to rapidly produce a live attenuated PIV1 vaccine candidate. The PIV1 vaccine candidate, designated rPIV3-1cp45, was generated by substituting the full-length HN and F proteins of PIV1 for those of PIV3 in the attenuated cp45 PIV3 vaccine candidate (T. Tao et al., J. Virol. 72:2955–2961, 1998; M. H. Skiadopoul...

  18. Intratumor injection of recombinant attenuated salmonella carrying Mycobacterium tuberculosis heat shock protein 70 and herpes simplex virus thymidine kinase genes to suppress murine melanoma growth%mtHSP70/HSV-tk重组沙门菌抗小鼠黑色素瘤的作用

    Institute of Scientific and Technical Information of China (English)

    曾曙光; 刘启才; 王素文; 彭细毛; 章锦才; 张积仁

    2012-01-01

    目的 研究携带结核杆菌热休克蛋白70(mtHSP70)、人单纯疱疹病毒一胸苷激酶(HSV-TK)双基因的重组沙门菌瘤内注射抗小鼠黑色素瘤的抑瘤效应.方法 构建重组沙门菌SL7207/PCMV-mtHSP70-IRES-TK,建立小鼠黑色素瘤动物模型,瘤内注射重组沙门菌观察其抑瘤效应、荷瘤鼠的生存期并进行安全性评估.结果 瘤内注射重组沙门菌,实验组抑瘤率显著高于对照组,延长荷瘤鼠生存期,重组菌治疗后荷瘤小鼠的生存状态良好,无腹泻,治疗期间体质量无明显改变.结论 减毒沙门菌携带的mtHSP70/HSV-TK双基因真核共表达质粒瘤内注射对B16肿瘤细胞具有显著抑制作用.%Objective To study the effection of suppression murine melanoma growth by Intratumor injection of recombinant attenuated salmonella carrying heat shock protein 70 and herpes simplex virus thymidine kinase genes. Methods Plasmids PCMV-mtHSP70-IRES-TK were electro-transferred into salmonella typhimurium SL7207 to construct recombinant salmonella typhimurium. In vivo, Recombinant bacteria were injected into the mouse melanoma and the antitumor effection was observed. The survival period was recorded and safety analysis for this vaccine in each group. Results In vivo, the mtHSP70/ HSV-tk recombinant bacteria can suppress tumor growth significantly and extend survival. After recombinant Salmonella, 10' CFU/mL, was administered as an intratumoral injection, No diarrhea were observed. During therapy, body weight did not change markedly. Conclusion Results of the animal experiment suggests intratumor injection of recombinant attenuated salmonella typhimurium containing mtHSP70 and HSV-tk genes, has targeting ability against B16 tumor cell and could significantly inhibit tumor growth.

  19. Recombination instability

    DEFF Research Database (Denmark)

    D'Angelo, N.

    1967-01-01

    A recombination instability is considered which may arise in a plasma if the temperature dependence of the volume recombination coefficient, alpha, is sufficiently strong. Two cases are analyzed: (a) a steady-state plasma produced in a neutral gas by X-rays or high energy electrons; and (b) an af...

  20. Use of microRNA Let-7 to control the replication specificity of oncolytic adenovirus in hepatocellular carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Huajun Jin

    Full Text Available Highly selective therapy for hepatocellular carcinoma (HCC remains an unmet medical need. In present study, we found that the tumor suppressor microRNA, let-7 was significantly downregulated in a proportion of primary HCC tissues (12 of 33, 36.4% and HCC cell lines. In line with this finding, we have engineered a chimeric Ad5/11 fiber oncolytic adenovirus, SG7011(let7T, by introducing eight copies of let-7 target sites (let7T into the 3' untranslated region of E1A, a key gene associated with adenoviral replication. The results showed that the E1A expression (both RNA and protein levels of the SG7011(let7T was tightly regulated according to the endogenous expression level of the let-7. As contrasted with the wild-type adenovirus and the control virus, the replication of SG7011(let7T was distinctly inhibited in normal liver cells lines (i.e. L-02 and WRL-68 expressing high level of let-7 (>300 folds, whereas was almost not impaired in HCC cells (i.e. Hep3B and PLC/PRF/5 with low level of let-7. Consequently, the cytotoxicity of SG7011(let7T to normal liver cells was successfully decreased while was almost not attenuated in HCC cells in vitro. The antitumor ability of SG7011(let7Tin vivo was maintained in mice with Hep3B xenograft tumor, whereas was greatly decreased against the SMMC-7721 xenograft tumor expressing a high level of let-7 similar with L-02 when compared to the wild-type adenovirus. These results suggested that SG7011(let7T may be a promising anticancer agent or vector to mediate the expression of therapeutic gene, broadly applicable in the treatment for HCC and other cancers where the let-7 gene is downregulated.

  1. Cellular factors promoting resistance to effective treatment of glioma with oncolytic myxoma virus.

    Science.gov (United States)

    Zemp, Franz J; McKenzie, Brienne A; Lun, Xueqing; Reilly, Karlyne M; McFadden, Grant; Yong, V Wee; Forsyth, Peter A

    2014-12-15

    Oncolytic virus therapy is being evaluated in clinical trials for human glioma. While it is widely assumed that the immune response of the patient to the virus infection limits the utility of the therapy, investigations into the specific cell type(s) involved in this response have been performed using nonspecific pharmacologic inhibitors or allogeneic models with compromised immunity. To identify the immune cells that participate in clearing an oncolytic infection in glioma, we used flow cytometry and immunohistochemistry to immunophenotype an orthotopic glioma model in immunocompetent mice after Myxoma virus (MYXV) administration. These studies revealed a large resident microglia and macrophage population in untreated tumors, and robust monocyte, T-, and NK cell infiltration 3 days after MYXV infection. To determine the role on the clinical utility of MYXV therapy for glioma, we used a combination of knockout mouse strains and specific immunocyte ablation techniques. Collectively, our experiments identify an important role for tumor-resident myeloid cells and overlapping roles for recruited NK and T cells in the clearance and efficacy of oncolytic MYXV from gliomas. Using a cyclophosphamide regimen to achieve lymphoablation prior and during MYXV treatment, we prevented treatment-induced peripheral immunocyte recruitment and, surprisingly, largely ablated the tumor-resident macrophage population. Virotherapy of cyclophosphamide-treated animals resulted in sustained viral infection within the glioma as well as a substantial survival advantage. This study demonstrates that resistance to MYXV virotherapy in syngeneic glioma models involves a multifaceted cellular immune response that can be overcome with cyclophosphamide-mediated lymphoablation.

  2. The ex vivo purge of cancer cells using oncolytic viruses: recent advances and clinical implications.

    Science.gov (United States)

    Tsang, Jovian J; Atkins, Harold L

    2015-01-01

    Hematological malignancies are treated with intensive high-dose chemotherapy, with or without radiation. This is followed by hematopoietic stem cell (HSC) transplantation (HSCT) to rescue or reconstitute hematopoiesis damaged by the anticancer therapy. Autologous HSC grafts may contain cancer cells and purging could further improve treatment outcomes. Similarly, allogeneic HSCT may be improved by selectively purging alloreactive effector cells from the graft rather than wholesale immune cell depletion. Viral agents that selectively replicate in specific cell populations are being studied in experimental models of cancer and immunological diseases and have potential applications in the context of HSC graft engineering. This review describes preclinical studies involving oncolytic virus strains of adenovirus, herpes simplex virus type 1, myxoma virus, and reovirus as ex vivo purging agents for HSC grafts, as well as in vitro and in vivo experimental studies using oncolytic coxsackievirus, measles virus, parvovirus, vaccinia virus, and vesicular stomatitis virus to eradicate hematopoietic malignancies. Alternative ex vivo oncolytic virus strategies are also outlined that aim to reduce the risk of relapse following autologous HSCT and mitigate morbidity and mortality due to graft-versus-host disease in allogeneic HSCT.

  3. Inhibition of Indoleamine-2,3-dioxygenase (IDO in Glioblastoma Cells by Oncolytic Herpes Simplex Virus

    Directory of Open Access Journals (Sweden)

    Bonnie Reinhart

    2012-01-01

    Full Text Available Successful oncolytic virus treatment of malignant glioblastoma multiforme depends on widespread tumor-specific lytic virus replication and escape from mitigating innate immune responses to infection. Here we characterize a new HSV vector, JD0G, that is deleted for ICP0 and the joint sequences separating the unique long and short elements of the viral genome. We observed that JD0G replication was enhanced in certain glioblastoma cell lines compared to HEL cells, suggesting that a vector backbone deleted for ICP0 may be useful for treatment of glioblastoma. The innate immune response to virus infection can potentially impede oncolytic vector replication in human tumors. Indoleamine-2,3-dioxygenase (IDO is expressed in response to interferon γ (IFNγ and has been linked to both antiviral functions and to the immune escape of tumor cells. We observed that IFNγ treatment of human glioblastoma cells induced the expression of IDO and that this expression was quelled by infection with both wild-type and JD0G viruses. The role of IDO in inhibiting virus replication and the connection of this protein to the escape of tumor cells from immune surveillance suggest that IDO downregulation by HSV infection may enhance the oncolytic activity of vectors such as JD0G.

  4. Preclinical evaluation of oncolytic vaccinia virus for therapy of canine soft tissue sarcoma.

    Directory of Open Access Journals (Sweden)

    Ivaylo Gentschev

    Full Text Available Virotherapy using oncolytic vaccinia virus (VACV strains is one promising new strategy for canine cancer therapy. In this study we describe the establishment of an in vivo model of canine soft tissue sarcoma (CSTS using the new isolated cell line STSA-1 and the analysis of the virus-mediated oncolytic and immunological effects of two different Lister VACV LIVP1.1.1 and GLV-1h68 strains against CSTS. Cell culture data demonstrated that both tested VACV strains efficiently infected and destroyed cells of the canine soft tissue sarcoma line STSA-1. In addition, in our new canine sarcoma tumor xenograft mouse model, systemic administration of LIVP1.1.1 or GLV-1h68 viruses led to significant inhibition of tumor growth compared to control mice. Furthermore, LIVP1.1.1 mediated therapy resulted in almost complete tumor regression and resulted in long-term survival of sarcoma-bearing mice. The replication of the tested VACV strains in tumor tissues led to strong oncolytic effects accompanied by an intense intratumoral infiltration of host immune cells, mainly neutrophils. These findings suggest that the direct viral oncolysis of tumor cells and the virus-dependent activation of tumor-associated host immune cells could be crucial parts of anti-tumor mechanism in STSA-1 xenografts. In summary, the data showed that both tested vaccinia virus strains and especially LIVP1.1.1 have great potential for effective treatment of CSTS.

  5. Entry of Oncolytic Herpes Simplex Virus into Human Squamous Cell Carcinoma Cells by Ultrasound

    Directory of Open Access Journals (Sweden)

    Shusuke Okunaga

    2015-10-01

    Full Text Available Low-intensity ultrasound is a useful method to introduce materials into cells due to the transient formation of micropores, called sonoporations, on the cell membrane. Whether oncolytic herpes simplex virus type 1 (HSV-1 can be introduced into oral squamous cell carcinoma (SCC cells through membrane pores remains undetermined. Human SCC cell line SAS and oncolytic HSV-1 RH2, which was deficient in the 134.5 gene and fusogenic, were used. Cells were exposed to ultrasound in the presence or absence of microbubbles. The increase of virus entry was estimated by plaque numbers. Viral infection was hardly established without the adsorption step, but plaque number was increased by the exposure of HSV-1-inoculated cells to ultrasound. Plaque number was also increased even if SAS cells were exposed to ultrasound and inoculated with RH2 without the adsorption step. This effect was abolished when the interval from ultrasound exposure to virus inoculation was prolonged. Scanning electron microscopy revealed depressed spots on the cell surface after exposure to ultrasound. These results suggest that oncolytic HSV-1 RH2 can be introduced into SAS cells through ultrasound-mediated pores of the cell membrane that are resealed after an interval.

  6. Recombination monitor

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, S. Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2017-02-03

    This is a brief report on LEReC recombination monitor design considerations. The recombination produced Au78+ ion rate is reviewed. Based on this two designs are discussed. One is to use the large dispersion lattice. It is shown that even with the large separation of the Au78+ beam from the Au79+ beam, the continued monitoring of the recombination is not possible. Accumulation of Au78+ ions is needed, plus collimation of the Au79+ beam. In another design, it is shown that the recombination monitor can be built based on the proposed scheme with the nominal lattice. From machine operation point of view, this design is preferable. Finally, possible studies and the alternative strategies with the basic goal of the monitor are discussed.

  7. The combination of i-leader truncation and gemcitabine improves oncolytic adenovirus efficacy in an immunocompetent model.

    Science.gov (United States)

    Puig-Saus, C; Laborda, E; Rodríguez-García, A; Cascalló, M; Moreno, R; Alemany, R

    2014-02-01

    Adenovirus (Ad) i-leader protein is a small protein of unknown function. The C-terminus truncation of the i-leader protein increases Ad release from infected cells and cytotoxicity. In the current study, we use the i-leader truncation to enhance the potency of an oncolytic Ad. In vitro, an i-leader truncated oncolytic Ad is released faster to the supernatant of infected cells, generates larger plaques, and is more cytotoxic in both human and Syrian hamster cell lines. In mice bearing human tumor xenografts, the i-leader truncation enhances oncolytic efficacy. However, in a Syrian hamster pancreatic tumor model, which is immunocompetent and less permissive to human Ad, antitumor efficacy is only observed when the i-leader truncated oncolytic Ad, but not the non-truncated version, is combined with gemcitabine. This synergistic effect observed in the Syrian hamster model was not seen in vitro or in immunodeficient mice bearing the same pancreatic hamster tumors, suggesting a role of the immune system in this synergism. These results highlight the interest of the i-leader C-terminus truncation because it enhances the antitumor potency of an oncolytic Ad and provides synergistic effects with gemcitabine in the presence of an immune competent system.

  8. Doxorubicin-enriched, ALDHbr mouse breast cancer stem cells are treatable to oncolytic herpes simplex virus type 1

    Directory of Open Access Journals (Sweden)

    Zhuang Xiufen

    2012-11-01

    Full Text Available Abstract Background The primary objective of this study was to test whether oncolytic herpes simplex virus type 1 (HSV1 could eradicate chemoresistant cancer stem cells (CSCs. Methods The fluorescent aldefluor reagent-based technique was used to identify and isolate ALDHbr cells as CSCs from the 4T1 murine breast cancer cell line. The presence of ALDHbr 4T1 cells was also examined in 4T1 breast cancer transplanted in immune-competent syngeneic mice. Results Compared with ALDHlo cells, ALDHbr cells had a markedly higher ability to form tumor spheres in vitro and a higher tumorigenic potential in vivo. ALDHbr cells also exhibited increased doxorubicin resistance in vitro, which correlated with a selective increase in the percentage of ALDHbr cells after doxorubicin treatment and an increased expression of P-glycoprotein (P-gp, a known chemoresistance factor. In contrast, oncolytic HSV1 was able to kill ALDHbr cells in vitro and even more markedly in vivo. Furthermore, in in vivo studies, systemic administration of doxorubicin followed by intratumoral injection of oncolytic HSV1 resulted in much more significant suppression of tumor growth with increased median survival period compared with each treatment given alone (p+ T lymphocytes were induced by oncolytic HSV1, no significant specific T cell response against CSCs was detected in vivo. Conclusions These results suggested that the use of oncolytic HSV1 following doxorubicin treatment may help eradicate residual chemoresistant CSCs in vivo.

  9. Patient-derived mesenchymal stem cells as delivery vehicles for oncolytic virotherapy: novel state-of-the-art technology.

    Science.gov (United States)

    Ramírez, Manuel; García-Castro, Javier; Melen, Gustavo J; González-Murillo, África; Franco-Luzón, Lidia

    2015-01-01

    Oncolytic virotherapy is gaining interest in the clinic as a new weapon against cancer. In vivo administration of oncolytic viruses showed important limitations that decrease their effectiveness very significantly: the antiviral immune response causes the elimination of the therapeutic effect, and the poor natural ability of oncolytic viruses to infect micrometastatic lesions significantly minimizes the effective dose of virus. This review will focus on updating the technical and scientific foundations of one of the strategies developed to overcome these limitations, ie, using cells as vehicles for oncolytic viruses. Among many candidates, a special type of adult stem cell, mesenchymal stem cells (MSCs), have already been used in the clinic as cell vehicles for oncolytic viruses, partly due to the fact that these cells are actively being evaluated for other indications. MSC carrier cells are used as Trojan horses loaded with oncoviruses, are administered systemically, and release their cargos at the right places. MSCs are equipped with an array of molecules involved in cell arrest in the capillaries (integrins and selectins), migration toward specific parenchymal locations within tissues (chemokine receptors), and invasion and degradation of the extracellular matrix (proteases). In addition to anatomical targeting capacity, MSCs have a well-recognized role in modulating immune responses by affecting cells of the innate (antigen-presenting cells, natural killer cells) and adaptive immune system (effector and regulatory lymphocytes). Therefore, carrier MSCs may also modulate the immune responses taking place after therapy, ie, the antiviral and the antitumor immune responses.

  10. Patient-derived mesenchymal stem cells as delivery vehicles for oncolytic virotherapy: novel state-of-the-art technology

    Directory of Open Access Journals (Sweden)

    Ramírez M

    2015-10-01

    Full Text Available Manuel Ramírez,1 Javier García-Castro,2 Gustavo J Melen,1 África González-Murillo,1 Lidia Franco-Luzón1 1Oncohematología, Hospital Universitario Niño Jesús, 2Unidad de Biotecnología Celular, Instituto de Salud Carlos III, Madrid, Spain Abstract: Oncolytic virotherapy is gaining interest in the clinic as a new weapon against cancer. In vivo administration of oncolytic viruses showed important limitations that decrease their effectiveness very significantly: the antiviral immune response causes the elimination of the therapeutic effect, and the poor natural ability of oncolytic viruses to infect micrometastatic lesions significantly minimizes the effective dose of virus. This review will focus on updating the technical and scientific foundations of one of the strategies developed to overcome these limitations, ie, using cells as vehicles for oncolytic viruses. Among many candidates, a special type of adult stem cell, mesenchymal stem cells (MSCs, have already been used in the clinic as cell vehicles for oncolytic viruses, partly due to the fact that these cells are actively being evaluated for other indications. MSC carrier cells are used as Trojan horses loaded with oncoviruses, are administered systemically, and release their cargos at the right places. MSCs are equipped with an array of molecules involved in cell arrest in the capillaries (integrins and selectins, migration toward specific parenchymal locations within tissues (chemokine receptors, and invasion and degradation of the extracellular matrix (proteases. In addition to anatomical targeting capacity, MSCs have a well-recognized role in modulating immune responses by affecting cells of the innate (antigen-presenting cells, natural killer cells and adaptive immune system (effector and regulatory lymphocytes. Therefore, carrier MSCs may also modulate the immune responses taking place after therapy, ie, the antiviral and the antitumor immune responses. Keywords: virotherapy

  11. Telomerase-specific oncolytic virotherapy for human hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    AIM: To evaluate the therapeutic efficiency of replicative adenovirus CNHK300 targeted in telomerase-positive hepatocellular carcinoma. METHODS: CNHK300, ONYX-015 (55 kDa protein deleted adenovirus) and wtAd5 (wild type adenovirus 5) were compared, and virus proliferation assay, cell viability assay, Western blot and fluorescence microscopy were used to evaluate the proliferation and cytolysis selectivity of CNHK300.RESULTS:The replicative multiples in Hep3B and HepG after 48 h of CNHK300 proliferation were 40625and 65326 fold, respectively, similar to that of wtAd5..However, CNHK300 exhibited attenuated replicative ability in normal fibroblast cell line BJ.CNHK300 could lyse hepatocellular carcinoma cells at a low multiplicity of infection (MOI),but could not affect growth of normal cells even at a high MOI.CONCLUSION:CNHK300 is a cancer-selective replication-competent adenovirus which can cause oncolysis of liver cancer cells as well as wtAd5 (wild type adenovirus 5),but had severely attenuated replicative and cytolytic ability in normal cells. This novel strategy of cancer treatment offers a promising treatment platform.

  12. The Research Progress of the Orally Attenuated Recombinant Salmonella Typhimurium Vector Vaccine%减毒沙门氏菌作为口服活疫苗载体的研究进展

    Institute of Scientific and Technical Information of China (English)

    马全英; 安芳兰; 刘萍; 祝秀梅; 吕志慧; 王凡; 刘学荣; 黄银君; 牟克斌

    2012-01-01

    文章就沙门氏菌相关基因的特点、减毒沙门氏菌载体激发的免疫应答、进入机体免疫系统的机制、减毒沙门氏菌的应用、载体疫苗的优越性及潜在危险性几方面综述了减毒沙门氏菌作为口服疫苗载体的研究进展,为新型菌苗的研制提供一种新的思路。%This article related genes from Salmonella characteristics of the related gene, attenuation salmonella carrier stimulate the immune re- sponse, into the mechanism of the immune system, the application of attenuated salmonella typhimurium, the superiority of vaccine vectors potentially dangerous areas and review of the attenuated salmonella as oral progress in a new type vaccine vectors for the development of novel vaccine provides a new way of thinking.

  13. Synergistic Antitumor Efficacy of Oncolytic Adenovirus Combined with Chemotherapy

    Institute of Scientific and Technical Information of China (English)

    LI Yue-min; QIAN Qi-jun; SONG San-tai; JIANG Ze-fei; ZHANG Qi; QU Yi-mei; SU Chang-qing; ZHAO Chuan-hua; LI Zhi-qiang; GE Fei-jiao

    2007-01-01

    Objective: Chemotherapy is an effective means of treating breast cancer, and cancer-specific replicative adenovirus is also a promising antitumor agent in recent years. Our investigation aims to demonstrate that CNHK300 can mediate selective antitumor efficacy and produce synergistic cytotoxicity with chemotherapy on HER-2 over-expressing breast cancer. Methods: We engineered the telomerase-dependent replicative adenovirus CNHK300 by placing the E1A gene under the control of the human hTERT promoter. By analysis of E1A expression, we proved the fidelity of hTERT promoter in adenovirus genome and the selective expression of E1A in telomerase-positive breast cancer cells but not in normal fibroblast cells. By proliferation test, we further showed efficient replication of CNHK300 in breast cancer cells with apparently attenuated proliferation in normal fibroblast cells. Finally, we demonstrated by MTT methods that CNHK300 virus caused potent cytolysis and produced synergistic cytotoxicity with chemotherapy in breast cancer cells with attenuated cytotoxicity on normal cells. Results: In this virus, the E1A gene is successfully placed under the control of the human hTERT promoter. CNHK300 virus replicated as efficiently as the wild-type adenovirus and caused intensive cell killing in HER-2 over-expressing breast cancer cells in vitro. In contrast, telomerase-negative normal fibroblast cells, which expressed no hTERT activity, were not able to support CNHK300 replication. Combined treatment of CNHK300 with paclitaxel improved cytotoxicity on cancer cells. Conclusion: We conclude that CNHK300 can produce selective antitumor efficacy and enhance the in vitro response of chemotherapy on HER-2 overexpressing breast cancer.

  14. Myxoma virus oncolytic efficiency can be enhanced through chemical or genetic disruption of the actin cytoskeleton.

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    Chad R Irwin

    Full Text Available Myxoma virus (MYXV is one of many animal viruses that exhibit oncolytic properties in transformed human cells. Compared to orthopoxviruses like vaccinia (VACV, MYXV spreads inefficiently, which could compromise its use in treating tumors and their associated metastases. The VACV F11 protein promotes virus exit and rapid spread by inhibiting Rho signalling, which results in a disruption of cortical actin. We have previously shown that although MYXV lacks an F11 homolog, the F11L gene can be introduced into MYXV promoting the spread of this Leporipoxvirus in natural host cells. Here we show that the F11-encoding (F11L(+ MYXV strain replicates to higher levels in a number of human cancer cells. We also show that F11L(+ MYXV induces better tumor control and prolonged survival of mice bearing MDA-MB-231 cancer cells. Furthermore, we show that this virus also spreads more efficiently from the site of growth in one injected tumor, to a second untreated tumor. While we focused mostly on the use of a modified MYXV we were able to show that the effects of F11 on MYXV growth in cancer cells could be mimicked through the use of pharmacological inhibition or siRNA-mediated silencing of key regulators of cortical actin (RhoA, RhoC, mDia1, or LIMK2. These data suggest that it may be possible to increase the oncolytic efficacy of wild-type MYXV using chemical inhibitors of RhoA/C or their downstream targets. Furthermore, since all viruses must overcome barriers to exit posed by structures like cortical actin, these findings suggest that the oncolytic activity of other viruses may be enhanced through similar strategies.

  15. Myxoma virus oncolytic efficiency can be enhanced through chemical or genetic disruption of the actin cytoskeleton.

    Science.gov (United States)

    Irwin, Chad R; Favis, Nicole A; Agopsowicz, Kate C; Hitt, Mary M; Evans, David H

    2013-01-01

    Myxoma virus (MYXV) is one of many animal viruses that exhibit oncolytic properties in transformed human cells. Compared to orthopoxviruses like vaccinia (VACV), MYXV spreads inefficiently, which could compromise its use in treating tumors and their associated metastases. The VACV F11 protein promotes virus exit and rapid spread by inhibiting Rho signalling, which results in a disruption of cortical actin. We have previously shown that although MYXV lacks an F11 homolog, the F11L gene can be introduced into MYXV promoting the spread of this Leporipoxvirus in natural host cells. Here we show that the F11-encoding (F11L(+)) MYXV strain replicates to higher levels in a number of human cancer cells. We also show that F11L(+) MYXV induces better tumor control and prolonged survival of mice bearing MDA-MB-231 cancer cells. Furthermore, we show that this virus also spreads more efficiently from the site of growth in one injected tumor, to a second untreated tumor. While we focused mostly on the use of a modified MYXV we were able to show that the effects of F11 on MYXV growth in cancer cells could be mimicked through the use of pharmacological inhibition or siRNA-mediated silencing of key regulators of cortical actin (RhoA, RhoC, mDia1, or LIMK2). These data suggest that it may be possible to increase the oncolytic efficacy of wild-type MYXV using chemical inhibitors of RhoA/C or their downstream targets. Furthermore, since all viruses must overcome barriers to exit posed by structures like cortical actin, these findings suggest that the oncolytic activity of other viruses may be enhanced through similar strategies.

  16. MicroRNA-mediated suppression of oncolytic adenovirus replication in human liver.

    Science.gov (United States)

    Ylösmäki, Erkko; Lavilla-Alonso, Sergio; Jäämaa, Sari; Vähä-Koskela, Markus; af Hällström, Taija; Hemminki, Akseli; Arola, Johanna; Mäkisalo, Heikki; Saksela, Kalle

    2013-01-01

    MicroRNAs (miRNAs) are important and ubiquitous regulators of gene expression that can suppress their target genes by translational inhibition as well as mRNA destruction. Cell type-specific miRNA expression patterns have been successfully exploited for targeting the expression of experimental and therapeutic gene constructs, for example to reduce pathogenic effects of cancer virotherapy in normal tissues. In order to avoid liver damage associated with systemic or intrahepatic delivery of oncolytic adenoviruses we have introduced the concept of suppressing adenovirus replication in hepatic cells by inserting target elements for the liver-specific miR122 into the viral genome. Here we show using ex vivo cultured tissue specimens that six perfectly complementary miR122 target sites in the 3' untranslated region of the viral E1A gene are sufficient in the absence of any other genetic modifications to prevent productive replication of serotype 5 adenovirus (Ad5) in normal human liver. This modification did not compromise the replicative capacity of the modified virus in cancer tissue derived from a colon carcinoma liver metastasis or its oncolytic potency in a human lung cancer xenograft mouse model. Unlike wild-type Ad5, the modified virus did not result in increased serum levels of liver enzymes in infected mice. These results provide a strong preclinical proof of concept for the use of miR122 target sites for reducing the risk of liver damage caused by oncolytic adenoviruses, and suggest that ectopic miR122 target elements should be considered as an additional safety measure included in any therapeutic virus or viral vector posing potential hazard to the liver.

  17. MicroRNA-mediated suppression of oncolytic adenovirus replication in human liver.

    Directory of Open Access Journals (Sweden)

    Erkko Ylösmäki

    Full Text Available MicroRNAs (miRNAs are important and ubiquitous regulators of gene expression that can suppress their target genes by translational inhibition as well as mRNA destruction. Cell type-specific miRNA expression patterns have been successfully exploited for targeting the expression of experimental and therapeutic gene constructs, for example to reduce pathogenic effects of cancer virotherapy in normal tissues. In order to avoid liver damage associated with systemic or intrahepatic delivery of oncolytic adenoviruses we have introduced the concept of suppressing adenovirus replication in hepatic cells by inserting target elements for the liver-specific miR122 into the viral genome. Here we show using ex vivo cultured tissue specimens that six perfectly complementary miR122 target sites in the 3' untranslated region of the viral E1A gene are sufficient in the absence of any other genetic modifications to prevent productive replication of serotype 5 adenovirus (Ad5 in normal human liver. This modification did not compromise the replicative capacity of the modified virus in cancer tissue derived from a colon carcinoma liver metastasis or its oncolytic potency in a human lung cancer xenograft mouse model. Unlike wild-type Ad5, the modified virus did not result in increased serum levels of liver enzymes in infected mice. These results provide a strong preclinical proof of concept for the use of miR122 target sites for reducing the risk of liver damage caused by oncolytic adenoviruses, and suggest that ectopic miR122 target elements should be considered as an additional safety measure included in any therapeutic virus or viral vector posing potential hazard to the liver.

  18. Single-particle characterization of oncolytic vaccinia virus by flow virometry.

    Science.gov (United States)

    Tang, Vera A; Renner, Tyler M; Varette, Oliver; Le Boeuf, Fabrice; Wang, Jiahu; Diallo, Jean-Simon; Bell, John C; Langlois, Marc-André

    2016-09-30

    Vaccinia virus (VV) is an oncolytic virus that is currently being evaluated as a promising cancer vaccine in several phase I, II and III clinical trials. Although several quality control tests are performed on each new batch of virus, these do not routinely include a systematic characterization of virus particle homogeneity, or relate the infectious titer to the total number of submicron sized particles (SSPs) present in the sample. SSPs are comprised of infectious virus and non-infectious viral particles, but also cell contaminants derived from the virus isolation procedures, such as cellular vesicles and debris. Here we have employed flow virometry (FV) analysis and sorting to isolate and characterize distinct SSP populations in therapeutic oncolytic VV preparations. We show that VV preparations contain SSPs heterogeneous in size and include large numbers of non-infectious VV particles. Furthermore, we used FV to illustrate how VV has a propensity to aggregate over time and under various handling and storage procedures. Accordingly, we find that together the infectious titer, the total number of SSPs, the number of viral genomes and the level of particle aggregation in a sample constitute useful parameters that greatly facilitate inter-sample assessment of physical quality, and also provides a means to monitor sample deterioration over time. Additionally, we have successfully employed FV sorting to further isolate virus from other particles by identifying a lipophilic dye that preferentially stains VV over other SSPs in the sample. Overall, we demonstrate that FV is a fast and effective tool that can be used to perform quality, and consistency control assessments of oncolytic VV vaccine preparations.

  19. Tumor suppressor in lung cancer-1 (TSLC1) mediated by dual-regulated oncolytic adenovirus exerts specific antitumor actions in a mouse model

    Institute of Scientific and Technical Information of China (English)

    Wen LEI; Hong-bin LIU; Shi-bing WANG; Xiu-mei ZHOU; Shui-di ZHENG; Ke-ni GUO; Bu-yun MA

    2013-01-01

    Aim:The tumor suppressor in lung cancer-1 (TSLC1) is a candidate tumor suppressor of lung cancer,and frequently inactivated in primary non-small cell lung cancer (NSCLC).In this study,we investigated the effects of TSLC1 mediated by a dual-regulated oncolytic adenovirus on lung cancer,and the mechanisms underlying the antitumor actions.Methods:The recombinant virus Ad·sp-E1A(△24)-TSLC1 was constructed by inserting the TSLC1 gene into the dual-regulated Ad·spE1A(△24) vector,which contained the survivin promoter and a 24 bp deletion within E1A.The antitumor effects of Ad·sp-E1A(△24)-TSLC1 were evaluated in NCI-H460,A549,and H1299 lung cancer cell lines and the normal fibroblast cell line MRC-5,as well as in A549 xenograft model in nude mice.Cell viability was assessed using MTT assay.The expression of TSLC1 and activation of the caspase signaling pathway were detected by Western blot analyses.The tumor tissues from the xenograft models were examined using H&E staining,IHC,TUNEL,and TEM analyses.Results:Infection of A549 lung cancer cells with Ad·sp-E1A(△24)-TSLC1 induced high level expression of TSLC1.Furthermore,the Ad·spE1A(△△24)-TSLC1 virus dose-dependently suppressed the viability of NCI-H460,A549,and H1299 lung cancer cells,and did not affect MRC-5 normal fibroblast cells.Infection of NCI-H460,A549,and H1299 lung cancer cells with Ad·sp-E1A(△24)-TSLC1 induced apoptosis,and increased activation of caspase-8,caspase-3 and PARR.In A549 xenograft model in nude mice,intratumoral injection of Ad.spE1A(△24)-TSLC1 significantly suppressed the tumor volume,and increased the survival rate (from less than 15% to 87.5% at d 60).Histological studies showed that injection of Ad·sp-E1A(△24)-TSLC1 caused tumor cell apoptosis and virus particle propagation in tumor tissues.Conclusion:The oncolytic adenovirus Ad·sp-E1A(△24)-TSLC1 exhibits specific antitumor effects,and is a promising agent for the treatment of lung cancer.

  20. Oncolytic adenovirus SG600-IL24 selectively kills hepatocellular carcinoma cell lines

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM: To investigate the effect of oncolytic adenovirus SG600-IL24 and replication-incompetent adenovirus Ad.IL-24 on hepatocellular carcinoma (HCC) cell lines and normal liver cell line. METHODS: HCC cell lines (HepG2, Hep3B and MHCC97L) and normal liver cell line (L02) with a different p53 status were infected with SG600-IL24 and Ad.IL-24, respectively. Melanoma differentiation-associated (MDA)-7/interleukin (IL)-24 mRNA and protein expressions in infected cells were detected by reverse transcription-polym...

  1. Establishing the lysine-rich protein CEST reporter gene as a CEST MR imaging detector for oncolytic virotherapy

    NARCIS (Netherlands)

    C.T. Farrar (Christian T.); J.S. Buhrman (Jason); G. Liu (Guanshu); A. Kleijn (Anne); M.L.M. Lamfers (Martine); M.T. McMahon (Michael T.); A.A. Gilad (Assaf A.); G. Fulci (Giulia)

    2015-01-01

    textabstractPurpose: To (a) evaluate whether the lysine-rich protein (LRP) magnetic resonance (MR) imaging reporter gene can be engineered into G47Δ, a herpes simplex-derived oncolytic virus that is currently being tested in clinical trials, without disrupting its therapeutic effectiveness and (b) e

  2. GP73-regulated oncolytic adenoviruses possess potent killing effect on human liver cancer stem-like cells

    Science.gov (United States)

    Zhang, Rong; Ma, Buyun; Liu, Tao; Yang, Yu; Xie, Wenjie; Liu, Xianglei; Huang, Fang; Liu, Tao; Zhou, Xiumei; Liu, Xinyuan; Wang, Yigang

    2016-01-01

    Cancer stem cells (CSCs), also known as tumor-initiating cells, are highly metastatic, chemo-resistant and tumorigenic, and are critical for cancer development, maintenance and recurrence. Oncolytic adenovirus could targetedly kill CSCs and has been acted as a promising anticancer agent. Currently, a novel GP73-regulated oncolytic adenovirus GD55 was constructed to specifically treat liver cancer and exhibited obvious cytotoxicity effect. However, there remains to be confirmed that whether GD55 could effectively eliminate liver CSCs. We first utilized the suspension culture to enrich the liver CSCs-like cells, which acquires the properties of liver CSCs in self-renewal, differentiation, quiescence, chemo-resistance and tumorigenicity. The results indicated that GD55 elicited more significant cytotoxicity and stronger oncolytic effect in liver CSC-like cells compared to common oncolytic virus ZD55. Additionally, GD55 possessed the greater efficacy in suppressing the growth of implanted tumors derived from liver CSC-like cells than ZD55. Furthermore, GD55 induced remarkable apoptosis of liver CSC-like cells in vitro and in vivo, and inhibited the propogation of cells and angiogenesis in xenograft tumor tissues. Thus, GD55 may virtually represent an attractive therapeutic agent for targeting liver CSCs to achieve better clinical outcomes for HCC patients. PMID:27121064

  3. Generation of an adenovirus-parvovirus chimera with enhanced oncolytic potential.

    Science.gov (United States)

    El-Andaloussi, Nazim; Bonifati, Serena; Kaufmann, Johanna K; Mailly, Laurent; Daeffler, Laurent; Deryckère, François; Nettelbeck, Dirk M; Rommelaere, Jean; Marchini, Antonio

    2012-10-01

    In this study, our goal was to generate a chimeric adenovirus-parvovirus (Ad-PV) vector that combines the high-titer and efficient gene transfer of adenovirus with the anticancer potential of rodent parvovirus. To this end, the entire oncolytic PV genome was inserted into a replication-defective E1- and E3-deleted Ad5 vector genome. As we found that parvoviral NS expression inhibited Ad-PV chimera production, we engineered the parvoviral P4 early promoter, which governs NS expression, by inserting into its sequence tetracycline operator elements. As a result of these modifications, P4-driven expression was blocked in the packaging T-REx-293 cells, which constitutively express the tetracycline repressor, allowing high-yield chimera production. The chimera effectively delivered the PV genome into cancer cells, from which fully infectious replication-competent parvovirus particles were generated. Remarkably, the Ad-PV chimera exerted stronger cytotoxic activities against various cancer cell lines, compared with the PV and Ad parental viruses, while being still innocuous to a panel of tested healthy primary human cells. This Ad-PV chimera represents a novel versatile anticancer agent which can be subjected to further genetic manipulations in order to reinforce its enhanced oncolytic capacity through arming with transgenes or retargeting into tumor cells.

  4. Oncolytic herpes simplex virus vectors for the treatment of human breast cancer

    Institute of Scientific and Technical Information of China (English)

    LIU Ren-bin; Samuel D.Rabkin

    2005-01-01

    Background Oncolytic herpes simplex virus (HSV) vectors can be used for cancer therapy as direct cytotoxic agents, inducers of anti-tumor immune responses, and as expressers of anti-cancer genes. In this study, the efficacy of HSV vectors, G47Δ and NV1023 were examined for the treatment of the human breast cancer.Methods Human breast cancer MDA-MB-435 cells were cultured or implanted subcutaneously in BALB/c nude mice. The cells or tumors were inoculated with G47Δ or NV1023, and cell killing or inhibition of tumor growth determined. Both viruses contained the LacZ gene and expression in infected cells was detected with X-gal histochemistry. Results G47Δ and NV1023 were highly cytotoxic to MDA-MB-435 cells in vitro at very low multiplicities of infection. X-gal staining of infected tumor cells in vitro and in vivo illustrated the replication and spread of both viruses. G47Δ and NV1023 inoculation inhibited tumor growth and prolonged mouse survival. Both vectors behaved similarly.Conclusions Oncolytic HSV vectors, G47Δ and NV1023, were extremely effective at killing human breast cancer cells in vitro and in tumor xenografts in vivo. This novel form of cancer therapy warrants further investigation and consideration of clinical application.

  5. Permissivity of the NCI-60 cancer cell lines to oncolytic Vaccinia Virus GLV-1h68

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    Bedognetti Davide

    2011-10-01

    Full Text Available Abstract Background Oncolytic viral therapy represents an alternative therapeutic strategy for the treatment of cancer. We previously described GLV-1h68, a modified Vaccinia Virus with exclusive tropism for tumor cells, and we observed a cell line-specific relationship between the ability of GLV-1h68 to replicate in vitro and its ability to colonize and eliminate tumor in vivo. Methods In the current study we surveyed the in vitro permissivity to GLV-1h68 replication of the NCI-60 panel of cell lines. Selected cell lines were also tested for permissivity to another Vaccinia Virus and a vesicular stomatitis virus (VSV strain. In order to identify correlates of permissity to viral infection, we measured transcriptional profiles of the cell lines prior infection. Results We observed highly heterogeneous permissivity to VACV infection amongst the cell lines. The heterogeneity of permissivity was independent of tissue with the exception of B cell derivation. Cell lines were also tested for permissivity to another Vaccinia Virus and a vesicular stomatitis virus (VSV strain and a significant correlation was found suggesting a common permissive phenotype. While no clear transcriptional pattern could be identified as predictor of permissivity to infection, some associations were observed suggesting multifactorial basis permissivity to viral infection. Conclusions Our findings have implications for the design of oncolytic therapies for cancer and offer insights into the nature of permissivity of tumor cells to viral infection.

  6. Preclinical evaluation of engineered oncolytic herpes simplex virus for the treatment of pediatric solid tumors.

    Directory of Open Access Journals (Sweden)

    Michael L Megison

    Full Text Available Recently, investigators showed that mice with syngeneic murine gliomas that were treated with a neuroattenuated oncolytic herpes simplex virus-1 (oHSV, M002, had a significant increase in survival. M002 has deletions in both copies of the γ134.5 gene, enabling replication in tumor cells but precluding infection of normal cells. Previous studies have shown antitumor effects of other oHSV against a number of adult tumors including hepatocellular carcinoma and renal cell carcinoma. The purpose of the current study was to investigate the oncolytic potential of M002 against difficult to treat pediatric liver and kidney tumors. We showed that the oHSV, M002, infected, replicated, and decreased cell survival in hepatoblastoma, malignant rhabdoid kidney tumor, and renal sarcoma cell lines. In addition, we showed that in murine xenografts, treatment with M002 significantly increased survival and decreased tumor growth. Finally, these studies showed that the primary entry protein for oHSV, CD111 (nectin-1 was present in human hepatoblastoma and malignant rhabdoid kidney tumor specimens. We concluded that M002 effectively targeted these rare aggressive tumor types and that M002 may have potential for use in children with unresponsive or relapsed pediatric solid tumors.

  7. Preclinical Evaluation of Engineered Oncolytic Herpes Simplex Virus for the Treatment of Pediatric Solid Tumors

    Science.gov (United States)

    Megison, Michael L.; Gillory, Lauren A.; Stewart, Jerry E.; Nabers, Hugh C.; Mroczek-Musulman, Elizabeth; Waters, Alicia M.; Coleman, Jennifer M.; Kelly, Virginia; Markert, James M.; Gillespie, G. Yancey; Friedman, Gregory K.; Beierle, Elizabeth A.

    2014-01-01

    Recently, investigators showed that mice with syngeneic murine gliomas that were treated with a neuroattenuated oncolytic herpes simplex virus-1 (oHSV), M002, had a significant increase in survival. M002 has deletions in both copies of the γ134.5 gene, enabling replication in tumor cells but precluding infection of normal cells. Previous studies have shown antitumor effects of other oHSV against a number of adult tumors including hepatocellular carcinoma and renal cell carcinoma. The purpose of the current study was to investigate the oncolytic potential of M002 against difficult to treat pediatric liver and kidney tumors. We showed that the oHSV, M002, infected, replicated, and decreased cell survival in hepatoblastoma, malignant rhabdoid kidney tumor, and renal sarcoma cell lines. In addition, we showed that in murine xenografts, treatment with M002 significantly increased survival and decreased tumor growth. Finally, these studies showed that the primary entry protein for oHSV, CD111 (nectin-1) was present in human hepatoblastoma and malignant rhabdoid kidney tumor specimens. We concluded that M002 effectively targeted these rare aggressive tumor types and that M002 may have potential for use in children with unresponsive or relapsed pediatric solid tumors. PMID:24497984

  8. Immunological effects of a tumor necrosis factor alpha-armed oncolytic adenovirus.

    Science.gov (United States)

    Hirvinen, Mari; Rajecki, Maria; Kapanen, Mika; Parviainen, Suvi; Rouvinen-Lagerström, Noora; Diaconu, Iulia; Nokisalmi, Petri; Tenhunen, Mikko; Hemminki, Akseli; Cerullo, Vincenzo

    2015-03-01

    For long it has been recognized that tumor necrosis factor alpha (TNFa) has anticancer characteristics, and its use as a cancer therapeutic was proposed already in the 1980s. However, its systemic toxicity has limited its usability. Oncolytic viruses, selectively cancer-killing viruses, have shown great potency, and one of their most useful aspects is their ability to produce high amounts of transgene products locally, resulting in high local versus systemic concentrations. Therefore, the overall magnitude of tumor cell killing results from the combination of oncolysis, transgene-mediated direct effect such as TNFa-mediated apoptosis, and, perhaps most significantly, from activation of the host immune system against the tumor. We generated a novel chimeric oncolytic adenovirus expressing human TNFa, Ad5/3-D24-hTNFa, whose efficacy and immunogenicity were tested in vitro and in vivo. The hTNFa-expressing adenovirus showed increased cancer-eradicating potency, which was shown to be because of elevated apoptosis and necrosis rates and induction of various immune responses. Interestingly, we saw increase in immunogenic cell death markers in Ad5/3-d24-hTNFa-treated cells. Moreover, tumors treated with Ad5/3-D24-hTNFa displayed enhanced presence of OVA-specific cytotoxic T cells. We thus can conclude that tumor eradication and antitumor immune responses mediated by Ad5/3-d24-hTNFa offer a new potential drug candidate for cancer therapy.

  9. Heat shock and heat shock protein 70i enhance the oncolytic effect of replicative adenovirus.

    Science.gov (United States)

    Haviv, Y S; Blackwell, J L; Li, H; Wang, M; Lei, X; Curiel, D T

    2001-12-01

    Replication-competent viruses are currently being evaluated for their cancer cell-killing properties. These vectors are designed to induce tumor regression after selective viral propagation within the tumor. However, replication-competent viruses have not resulted heretofore in complete tumor eradication in the clinical setting. Recently, heat shock has been reported to partially alleviate replication restriction on an avian adenovirus (Ad) in a human lung cancer cell line. Therefore, we hypothesized that heat shock and overexpression of heat shock protein (hsp) would support the oncolytic effect of a replication-competent human Ad. To this end, we tested the oncolytic and burst kinetics of a replication-competent Ad after exposure to heat shock or to inducible hsp 70 overexpression by a replication-deficient Ad (Adhsp 70i). Heat-shock resulted in augmentation of Ad burst and oncolysis while decreasing total intracellular Ad DNA. Overexpression of hsp 70i also enhanced Ad-mediated oncolysis but did not decrease intracellular Ad DNA levels. We conclude that heat shock and Adhsp 70i enhance the Ad cell-killing potential via distinct mechanisms. A potential therapeutic implication would be the use of local hyperthermia to augment oncolysis by increasing the burst of replication-competent Ad. The role of hsp in Ad-mediated oncolysis should be additionally explored.

  10. Myxoma virus suppresses proliferation of activated T lymphocytes yet permits oncolytic virus transfer to cancer cells.

    Science.gov (United States)

    Villa, Nancy Y; Wasserfall, Clive H; Meacham, Amy M; Wise, Elizabeth; Chan, Winnie; Wingard, John R; McFadden, Grant; Cogle, Christopher R

    2015-06-11

    Allogeneic hematopoietic cell transplant (allo-HCT) can be curative for certain hematologic malignancies, but the risk of graft-versus-host disease (GVHD) is a major limitation for wider application. Ideally, strategies to improve allo-HCT would involve suppression of T lymphocytes that drive GVHD while sparing those that mediate graft-versus-malignancy (GVM). Recently, using a xenograft model, we serendipitously discovered that myxoma virus (MYXV) prevented GVHD while permitting GVM. In this study, we show that MYXV binds to resting, primary human T lymphocytes but will only proceed into active virus infection after the T cells receive activation signals. MYXV-infected T lymphocytes exhibited impaired proliferation after activation with reduced expression of interferon-γ, interleukin-2 (IL-2), and soluble IL-2Rα, but did not affect expression of IL-4 and IL-10. MYXV suppressed T-cell proliferation in 2 patterns (full vs partial) depending on the donor. In terms of GVM, we show that MYXV-infected activated human T lymphocytes effectively deliver live oncolytic virus to human multiple myeloma cells, thus augmenting GVM by transfer of active oncolytic virus to residual cancer cells. Given this dual capacity of reducing GVHD plus increasing the antineoplastic effectiveness of GVM, ex vivo virotherapy with MYXV may be a promising clinical adjunct to allo-HCT regimens.

  11. Assessment of the Na/I symporter as a reporter gene to visualize oncolytic adenovirus propagation in peritoneal tumours

    Energy Technology Data Exchange (ETDEWEB)

    Merron, Andrew; McNeish, Iain A. [Queen Mary' s School of Medicine and Dentistry, Centre for Molecular Oncology, Institute of Cancer, London (United Kingdom); Baril, Patrick; Tran, Lucile; Vassaux, Georges [CHU Hotel Dieu, INSERM, Nantes (France); CHU de Nantes, Institut des Maladies de l' Appareil Digestif, Nantes (France); Martin-Duque, Pilar [Instituto Aragones de Ciencias de la Salud, Zaragoza (Spain); Vieja, Antonio de la [Instituto de Investigaciones Biomedicas, Madrid (Spain); Briat, Arnaud [INSERM U877, Grenoble (France); Harrington, Kevin J. [Chester Beatty Laboratories, Institute of Cancer Research, London (United Kingdom)

    2010-07-15

    In vivo imaging of the spread of oncolytic viruses using the Na/I symporter (NIS) has been proposed. Here, we assessed whether the presence of NIS in the viral genome affects the therapeutic efficacy of the oncolytic adenovirus dl922-947 following intraperitoneal administration, in a mouse model of peritoneal ovarian carcinoma. We generated AdAM7, a dl922-947 oncolytic adenovirus encoding the NIS coding sequence. Iodide uptake, NIS expression, infectivity and cell-killing activity of AdAM7, as well as that of relevant controls, were determined in vitro. In vivo, the propagation of this virus in the peritoneal cavity of tumour-bearing mice was determined using SPECT/CT imaging and its therapeutic efficacy was evaluated. In vitro infection of ovarian carcinoma IGROV-1 cells with ADAM7 led to functional expression of NIS. However, the insertion of NIS into the viral genome resulted in a loss of efficacy of the virus in terms of replication and cytotoxicity. In vivo, on SPECT/CT imaging AdAM7 was only detectable in the peritoneal cavity of animals bearing peritoneal ovarian tumours for up to 5 days after intraperitoneal administration. Therapeutic experiments in vivo demonstrated that AdAM7 is as potent as its NIS-negative counterpart. This study demonstrated that despite the detrimental effect observed in vitro, insertion of the reporter gene NIS in an oncolytic adenovirus did not affect its therapeutic efficacy in vivo. We conclude that NIS is a highly relevant reporter gene to monitor the fate of oncolytic adenovectors in live subjects. (orig.)

  12. Therapeutic Use of Native and Recombinant Enteroviruses.

    Science.gov (United States)

    Ylä-Pelto, Jani; Tripathi, Lav; Susi, Petri

    2016-02-23

    Research on human enteroviruses has resulted in the identification of more than 100 enterovirus types, which use more than 10 protein receptors and/or attachment factors required in cell binding and initiation of the replication cycle. Many of these "viral" receptors are overexpressed in cancer cells. Receptor binding and the ability to replicate in specific target cells define the tropism and pathogenesis of enterovirus types, because cellular infection often results in cytolytic response, i.e., disruption of the cells. Viral tropism and cytolytic properties thus make native enteroviruses prime candidates for oncolytic virotherapy. Copy DNA cloning and modification of enterovirus genomes have resulted in the generation of enterovirus vectors with properties that are useful in therapy or in vaccine trials where foreign antigenic epitopes are expressed from or on the surface of the vector virus. The small genome size and compact particle structure, however, set limits to enterovirus genome modifications. This review focuses on the therapeutic use of native and recombinant enteroviruses and the methods that have been applied to modify enterovirus genomes for therapy.

  13. Therapeutic Use of Native and Recombinant Enteroviruses

    Directory of Open Access Journals (Sweden)

    Jani Ylä-Pelto

    2016-02-01

    Full Text Available Research on human enteroviruses has resulted in the identification of more than 100 enterovirus types, which use more than 10 protein receptors and/or attachment factors required in cell binding and initiation of the replication cycle. Many of these “viral” receptors are overexpressed in cancer cells. Receptor binding and the ability to replicate in specific target cells define the tropism and pathogenesis of enterovirus types, because cellular infection often results in cytolytic response, i.e., disruption of the cells. Viral tropism and cytolytic properties thus make native enteroviruses prime candidates for oncolytic virotherapy. Copy DNA cloning and modification of enterovirus genomes have resulted in the generation of enterovirus vectors with properties that are useful in therapy or in vaccine trials where foreign antigenic epitopes are expressed from or on the surface of the vector virus. The small genome size and compact particle structure, however, set limits to enterovirus genome modifications. This review focuses on the therapeutic use of native and recombinant enteroviruses and the methods that have been applied to modify enterovirus genomes for therapy.

  14. Vaccine development using recombinant DNA technology

    Science.gov (United States)

    Vaccines induce an immune response in the host that subsequently recognizes infectious agents and helps fight off the disease; vaccines must do this without causing the disease. This paper reviews the development of recombinant DNA technologies as a means of providing new ways for attenuating diseas...

  15. Targeting gallbladder cancer: oncolytic virotherapy with myxoma virus is enhanced by rapamycin in vitro and further improved by hyaluronan in vivo

    OpenAIRE

    Weng, Mingzhe; Gong, Wei; Ma, Mingzhe; Chu, Bingfeng; Qin, Yiyu; Zhang, Mingdi; Lun, XueQing; McFadden, Grant; Forsyth, Peter; Yong YANG; Quan, Zhiwei

    2014-01-01

    Background Gallbladder carcinoma (GBC) is highly lethal, and effective treatment will require synergistic anti-tumor management. The study is aimed at investigating the oncolytic value of myxoma virus (MYXV) infection against GBC and optimizing MYXV oncolytic efficiency. Methods We examined the permissiveness of GBC cell lines to MYXV infection and compared the effects of MYXV on cell viability among GBC and control permissive glioma cells in vitro and in vivo after MYXV + rapamycin (Rap) tre...

  16. Postexposure Protection Against Marburg Haemorrhagic Fever with Recombinant Vesicular Stomatitis Virus Vectors in Non-Human Primates: An Efficacy Assessment

    Science.gov (United States)

    2006-04-29

    virus (MARV). We aimed to test the effi cacy of a replication -competent vaccine based on attenuated recombinant vesicular stomatitis virus (rVSV...including vaccines based on recombinant adenoviruses12,13 and recombinant alphaviruses .8 We previously described the generation and assessment of a live...such as Marburg virus (MARV). We aimed to test the efficacy of a replication -competent vaccine based on attenuated recombinant vesicular stomatitis

  17. Construction and infectivity analysis of live attenuated recombinant salmonella expressing HIV-1 447-52D epitope on fimbriae%以沙门氏菌菌毛为载体的重组HIV-1 447-52D表位疫苗的构建和毒力检测

    Institute of Scientific and Technical Information of China (English)

    金刚; 于璐; 岳超; 李海宁; 杨全; 李庆海; 刘树林

    2016-01-01

    Objective To construct recombinant attenuated Salmonella expressing the HIV-1 447-52D epitope on the thin aggregative fimbriae and to analyze the infectivity status of this recombinant strain.Methods The recombinant attenuated Salmonella ST-44752D was constructed by using pHSG415 gene replacement system to replace the wild-type agfA gene with the chimeric agfA:44752D gene and then verified by polymeruse chain reaction(PCR) and sequencing.The expression of the recombinant thin aggregative fimbriae was analyzed by Western blotting.Congo red binding test was performed to examine the adsorbability of fimbriae.50% lethal dose (LD50) and organ distribution status of the 447-52D strain were determined in mice.Results The 447-52D expressing recombinant strain was successfully constructed and confirmed by DNA sequencing.Compared with wild-type ST,recombinant ST-44752D strain showed similar expression level of the thin aggregative fimbriae AgfA,and similar binding activity to Congo red reagent.The LD50 value of ST-44752D strain in mice was 1.45 × 109 CFU.After infection,ST-44752D strain could distribute effectively in spleen and lymph node,similar to wild-type ST.Conclusion The recombinant attenuated Salmonella typhimurium ST-44752D harboring HIV-1 447-52D epitope on fimbriae was successfully constructed.The 447-52D epitope within AgfA did not influence AgfA expression,fimbrial adsorbability,bacterial LDS0 value or organ distribution in mice.%目的 构建菌毛上表达HIV-1 447-52D表位的减毒Salmonella typhimurium ST14028-3b aroA-44752D,并对其毒力进行检测.方法 利用同源重组技术,将447-52D表位整合至沙门氏菌细聚合菌毛上,Western blot检测其表达情况,通过刚果红结合实验分析外源表位对菌毛吸附能力的影响.感染动物后检测重组菌的毒力及其在小鼠体内的分布.结果 重组菌的嵌合基因片段测序结果和嵌合蛋白的表达分析表明,重组菌菌毛上成功表达外源447-52D表位.重

  18. Construction of a recombinant-attenuated Salmonella Enteritidis strain secreting Escherichia coli heat-labile enterotoxin B subunit protein and its immunogenicity and protection efficacy against salmonellosis in chickens.

    Science.gov (United States)

    Nandre, Rahul M; Lee, John Hwa

    2014-01-09

    A live attenuated Salmonella Enteritidis (SE) strain secreting Escherichia coli heat-labile enterotoxin B subunit (LTB) protein was constructed as a new vaccine candidate. The comparative effect of this vaccine candidate was evaluated with a previously reported SE vaccine, JOL919. An asd+, p15A ori plasmid containing eltB-encoding LTB was introduced into a ΔlonΔcpxRΔasd SE strain, and designated as JOL1364. In a single immunization experiment, group A chickens were orally inoculated with phosphate-buffered saline as a control, group B chickens were orally immunized with JOL919, and group C chickens were orally immunized with JOL1364. The immunized groups B and C showed significantly higher systemic, mucosal and cellular immune responses as compared to those of the control group. In addition, the immunized group C showed significantly higher mucosal and cellular immune responses as compared to those of the immunized group B at the 1st week post-immunization. In the examination of protection efficacy, the immunized groups B and C showed lower gross lesion scores in the liver and spleen, and lower bacterial counts of SE challenge strain in the liver, spleen, and caeca as compared to those of the control group. The number of SE-positive birds was significantly lower in the immunized group C as compared to that of the control group at the 14th day post-challenge. In addition, the number of birds carrying the challenge strain in the caeca was significantly lower in the immunized group C than those in the immunized group B and control group at the 7th and 14th day post-challenge. These results indicate that immunization with the JOL1364 vaccine candidate can induce higher mucosal and cellular immune responses than those of the JOL919 for efficient protection against salmonellosis.

  19. Interferon-β-armed oncolytic adenovirus induces both apoptosis and necroptosis in cancer cells

    Institute of Scientific and Technical Information of China (English)

    Hongling Huang; Tian Xiao; Lingfeng He; Hongbin Ji; Xin-Yuan Liu

    2012-01-01

    Interferon-β (IFN-β) has been widely used in cancer therapy,but the clinical trial results are generally disappointing.Our previous studies have shown that an oncolytic adenovirus carrying IFN-β (ZD55-IFN-β) exhibits significant anti-tumor activities.However,the underlying mechanisms are not clear.Here we showed that ZD55-IFN-β infection-induced S-phase cell cycle arrest in a p53-dependent manner by activating the ataxia telangiectasia mutated-dependent DNA damage pathway.In addition, ZD55-IFN-β infection could initiate both caspase-dependent apoptosis and necroptosis in cancer cells.More importantly,ZD55-IFN-β showed a synergistic effect on cancer cells when combined with doxorubicin.These results suggest that the combination of ZD55-IFN-β with doxorubicin may represent a promising clinical strategy in cancer therapy.

  20. Characterization of the Antiglioma Effect of the Oncolytic Adenovirus VCN-01.

    Directory of Open Access Journals (Sweden)

    Beatriz Vera

    Full Text Available Despite the recent advances in the development of antitumor therapies, the prognosis for patients with malignant gliomas remains dismal. Therapy with tumor-selective viruses is emerging as a treatment option for this devastating disease. In this study we characterize the anti-glioma effect of VCN-01, an improved hyaluronidase-armed pRB-pathway-selective oncolytic adenovirus that has proven safe and effective in the treatment of several solid tumors. VCN-01 displayed a significant cytotoxic effect on glioma cells in vitro. In vivo, in two different orthotopic glioma models, a single intra-tumoral administration of VCN-01 increased overall survival significantly and led to long-term survivors free of disease.

  1. Clinical development of reovirus for cancer therapy: An oncolytic virus with immune-mediated antitumor activity

    Science.gov (United States)

    Gong, Jun; Sachdev, Esha; Mita, Alain C; Mita, Monica M

    2016-01-01

    Reovirus is a double-stranded RNA virus with demonstrated oncolysis or preferential replication in cancer cells. The oncolytic properties of reovirus appear to be dependent, in part, on activated Ras signaling. In addition, Ras-transformation promotes reovirus oncolysis by affecting several steps of the viral life cycle. Reovirus-mediated immune responses can present barriers to tumor targeting, serve protective functions against reovirus systemic toxicity, and contribute to therapeutic efficacy through antitumor immune-mediated effects via innate and adaptive responses. Preclinical studies have demonstrated the broad anticancer activity of wild-type, unmodified type 3 Dearing strain reovirus (Reolysin®) across a spectrum of malignancies. The development of reovirus as an anticancer agent and available clinical data reported from 22 clinical trials will be reviewed. PMID:27019795

  2. Clinical development of reovirus for cancer therapy: An oncolytic virus with immune-mediated antitumor activity.

    Science.gov (United States)

    Gong, Jun; Sachdev, Esha; Mita, Alain C; Mita, Monica M

    2016-03-26

    Reovirus is a double-stranded RNA virus with demonstrated oncolysis or preferential replication in cancer cells. The oncolytic properties of reovirus appear to be dependent, in part, on activated Ras signaling. In addition, Ras-transformation promotes reovirus oncolysis by affecting several steps of the viral life cycle. Reovirus-mediated immune responses can present barriers to tumor targeting, serve protective functions against reovirus systemic toxicity, and contribute to therapeutic efficacy through antitumor immune-mediated effects via innate and adaptive responses. Preclinical studies have demonstrated the broad anticancer activity of wild-type, unmodified type 3 Dearing strain reovirus (Reolysin(®)) across a spectrum of malignancies. The development of reovirus as an anticancer agent and available clinical data reported from 22 clinical trials will be reviewed.

  3. Distinct host cell fates for human malignant melanoma targeted by oncolytic rodent parvoviruses.

    Science.gov (United States)

    Vollmers, Ellen M; Tattersall, Peter

    2013-11-01

    The rodent parvoviruses are known to be oncoselective, and lytically infect many transformed human cells. Because current therapeutic regimens for metastatic melanoma have low response rates and have little effect on improving survival, this disease is a prime candidate for novel approaches to therapy, including oncolytic parvoviruses. Screening of low-passage, patient-derived melanoma cell lines for multiplicity-dependent killing by a panel of five rodent parvoviruses identified LuIII as the most melanoma-lytic. This property was mapped to the LuIII capsid gene, and an efficiently melanoma tropic chimeric virus shown to undergo three types of interaction with primary human melanoma cells: (1) complete lysis of cultures infected at very low multiplicities; (2) acute killing resulting from viral protein synthesis and DNA replication, without concomitant expansion of the infection, due to failure to export progeny virions efficiently; or (3) complete resistance that operates at an intracellular step following virion uptake, but preceding viral transcription.

  4. A targeting ligand enhances infectivity and cytotoxicity of an oncolytic adenovirus in human pancreatic cancer tissues.

    Science.gov (United States)

    Yamamoto, Yuki; Hiraoka, Nobuyoshi; Goto, Naoko; Rin, Yosei; Miura, Kazuki; Narumi, Kenta; Uchida, Hiroaki; Tagawa, Masatoshi; Aoki, Kazunori

    2014-10-28

    The addition of a targeting strategy is necessary to enhance oncolysis and secure safety of a conditionally replicative adenovirus (CRAd). We have constructed an adenovirus library displaying random peptides on the fiber, and have successfully identified a pancreatic cancer-targeting ligand (SYENFSA). Here, the usefulness of cancer-targeted CRAd for pancreatic cancer was examined as a preclinical study. First, we constructed a survivin promoter-regulated CRAd expressing enhanced green fluorescent protein gene (EGFP), which displayed the identified targeting ligand (AdSur-SYE). The AdSur-SYE resulted in higher gene transduction efficiency and oncolytic potency than the untargeted CRAd (AdSur) in several pancreatic cancer cell lines. An intratumoral injection of AdSur-SYE significantly suppressed the growth of subcutaneous tumors, in which AdSur-SYE effectively proliferated and spread. An ectopic infection in adjacent tissues and organs of intratumorally injected AdSur-SYE was decreased compared with AdSur. Then, to examine whether the targeting ligand actually enhanced the infectivity of CRAd in human pancreatic cancer tissues, tumor cells prepared from surgical specimens were infected with viruses. The AdSur-SYE increased gene transduction efficiency 6.4-fold higher than did AdSur in single cells derived from human pancreatic cancer, whereas the infectivity of both vectors was almost the same in the pancreas and other cancers. Immunostaining showed that most EGFP(+) cells were cytokeratin-positive in the sliced tissues, indicating that pancreatic cancer cells but not stromal cells were injected with AdSur-SYE. AdSur-SYE resulted in a stronger oncolysis in the primary pancreatic cancer cells co-cultured with mouse embryonic fibroblasts than AdSur did. CRAd in combination with a tumor-targeting ligand is promising as a next-generation of oncolytic virotherapy for pancreatic cancer.

  5. p21 promotes oncolytic adenoviral activity in ovarian cancer and is a potential biomarker

    Directory of Open Access Journals (Sweden)

    Lockley Michelle

    2010-07-01

    Full Text Available Abstract The oncolytic adenovirus dl922-947 replicates selectively within and lyses cells with a dysregulated Rb pathway, a finding seen in > 90% human cancers. dl922-947 is more potent than wild type adenovirus and the E1B-deletion mutant dl1520 (Onyx-015. We wished to determine which host cell factors influence cytotoxicity. SV40 large T-transformed MRC5-VA cells are 3-logs more sensitive to dl922-947 than isogenic parental MRC5 cells, confirming that an abnormal G1/S checkpoint increases viral efficacy. The sensitivity of ovarian cancer cells to dl922-947 varied widely: IC50 values ranged from 51 (SKOV3ip1 to 0.03 pfu/cell (TOV21G. Cells sensitive to dl922-947 had higher S phase populations and supported earlier E1A expression. Cytotoxicity correlated poorly with both infectivity and replication, but well with expression of p21 by microarray and western blot analyses. Matched p21+/+ and -/- Hct116 cells confirmed that p21 influences dl922-947 activity in vitro and in vivo. siRNA-mediated p21 knockdown in sensitive TOV21G cells decreases E1A expression and viral cytotoxicity, whilst expression of p21 in resistant A2780CP cells increases virus activity in vitro and in intraperitoneal xenografts. These results highlight that host cell factors beyond simple infectivity can influence the efficacy of oncolytic adenoviruses. p21 expression may be an important biomarker of response in clinical trials.

  6. Myxoma Virus Sensitizes Cancer Cells to Gemcitabine and Is an Effective Oncolytic Virotherapeutic in Models of Disseminated Pancreatic Cancer

    OpenAIRE

    Wennier, Sonia Tusell; Liu, Jia; Li, Shoudong; Rahman, Masmudur M.; Mona, Mahmoud; McFadden, Grant

    2012-01-01

    Myxoma virus (MYXV) is a novel oncolytic virus that has been shown to replicate in pancreatic cancer cells, but its efficacy in animal models of pancreatic cancer has not been determined. The efficacy of MYXV as monotherapy or in combination with gemcitabine was evaluated in intraperitoneal dissemination (IPD) models of pancreatic cancer. The effects of an intact immune system on the efficacy of MYXV therapy was tested by comparing immunodeficient versus immunocompetent murine models and comb...

  7. Imaging of intratumoral inflammation during oncolytic virotherapy of tumors by 19F-magnetic resonance imaging (MRI.

    Directory of Open Access Journals (Sweden)

    Stephanie Weibel

    Full Text Available BACKGROUND: Oncolytic virotherapy of tumors is an up-coming, promising therapeutic modality of cancer therapy. Unfortunately, non-invasive techniques to evaluate the inflammatory host response to treatment are rare. Here, we evaluate (19F magnetic resonance imaging (MRI which enables the non-invasive visualization of inflammatory processes in pathological conditions by the use of perfluorocarbon nanoemulsions (PFC for monitoring of oncolytic virotherapy. METHODOLOGY/PRINCIPAL FINDINGS: The Vaccinia virus strain GLV-1h68 was used as an oncolytic agent for the treatment of different tumor models. Systemic application of PFC emulsions followed by (1H/(19F MRI of mock-infected and GLV-1h68-infected tumor-bearing mice revealed a significant accumulation of the (19F signal in the tumor rim of virus-treated mice. Histological examination of tumors confirmed a similar spatial distribution of the (19F signal hot spots and CD68(+-macrophages. Thereby, the CD68(+-macrophages encapsulate the GFP-positive viral infection foci. In multiple tumor models, we specifically visualized early inflammatory cell recruitment in Vaccinia virus colonized tumors. Furthermore, we documented that the (19F signal correlated with the extent of viral spreading within tumors. CONCLUSIONS/SIGNIFICANCE: These results suggest (19F MRI as a non-invasive methodology to document the tumor-associated host immune response as well as the extent of intratumoral viral replication. Thus, (19F MRI represents a new platform to non-invasively investigate the role of the host immune response for therapeutic outcome of oncolytic virotherapy and individual patient response.

  8. Combination effect of oncolytic adenovirus therapy and herpes simplex virus thymidine kinase/ganciclovir in hepatic carcinoma animal models

    Institute of Scientific and Technical Information of China (English)

    Fei-qun ZHENG; Yin XU; Ren-jie YANG; Bin WU; Xiao-hua TAN; Yi-de QIN; Qun-wei ZHANG

    2009-01-01

    Aim: Oncolytic adenovirus, also called conditionally replicating adenovirus (CRAD), can selectively propagate in tumor cells and cause cell lysis. The released viral progeny can infect neighboring cancer cells, initiating a cascade that can lead to the ultimate destruction of the tumor. Suicide gene therapy using herpes simplex virus thymidine kinase (HSV-TK) and ganciclovir (GCV) offers a potential treatment strategy for cancer and is undergoing preclinical trials for a variety of tumors.We hypothesized that HSV-TK gene therapy combined with oncolytic adenoviral therapy would have an enhanced effect compared with the individual effects of the therapies and is a potential novel therapeutic strategy to treat liver cancer. Methods: To address our hypothesis, a novel CRAD was created, which consisted of a telomerase-dependent oncolytic adenovirus engineered to express E1A and HSV-TK genes (Ad-ETK). The combined effect of Ad-ETK and GCV was assessed both in vitro and in vivo in nude mice bearing HepG2 cell-derived tumors. Expression of the therapeutic genes by the transduced tumor cells was analyzed by RT-PCR and Western blotting.Results: We confirmed that Ad-ETK had antitumorigenic effects on human hepatocellular carcinoma (HCC) both in vitro and in vivo, and the TK/GCV system enhanced oncolytic adenoviral therapy. We confirmed that both E1A and HSV-TK genes were expressed in vivo.Conclusion: The Ad-ETK construct should provide a relatively safe and selective approach to killing cancer cells and should be investigated as an adjuvant therapy for hepatocellular carcinoma.

  9. 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.

  10. Survivin promoter-regulated oncolytic adenovirus with Hsp70 gene exerts effective antitumor efficacy in gastric cancer immunotherapy

    OpenAIRE

    Wang, Weiguo; Ji, Weidan; Hu, Huanzhang; Ma, Juming; Li, Xiaoya; Mei, Weiqun; Xu, Yang; Hu, Huizhen; Yan, Yan; Song, Qizhe; Li, Zhigang; Su, Changqing

    2013-01-01

    Gene therapy is a promising adjuvant therapeutic strategy for cancer treatment. To overcome the limitations of current gene therapy, such as poor transfection efficiency of vectors, low levels of transgene expression and lack of tumor targeting, the Survivin promoter was used to regulate the selective replication of oncolytic adenovirus in tumor cells, and the heat shock protein 70 (Hsp70) gene was loaded as the anticancer transgene to generate an AdSurp-Hsp70 viral therapy system. The effica...

  11. Selective purging of human multiple myeloma cells from autologous stem cell transplant grafts using oncolytic myxoma virus

    OpenAIRE

    Bartee, Eric; Chan, Winnie S.; Moreb, Jan S.; Cogle, Christopher R.; McFadden, Grant

    2012-01-01

    Autologous stem cell transplantation (ASCT) and novel therapies have improved overall survival of patients with multiple myeloma; however, most patients relapse and eventually succumb to their disease. Evidence indicates that residual cancer cells contaminate autologous grafts and may contribute to early relapses after ASCT. Here, we demonstrate that ex vivo treatment with an oncolytic poxvirus called myxoma virus results in specific elimination of human myeloma cells by inducing rapid cellul...

  12. Retargeted oncolytic adenovirus displaying a single variable domain of camelid heavy-chain-only antibody in a fiber protein.

    Science.gov (United States)

    van Erp, Elisabeth A; Kaliberova, Lyudmila N; Kaliberov, Sergey A; Curiel, David T

    2015-01-01

    Conditionally replicative adenoviruses are promising agents for oncolytic virotherapy. Various approaches have been attempted to retarget adenoviruses to tumor-specific antigens to circumvent deficiency of receptor for adenoviral binding and to provide an additional level of tumor specificity. Functional incorporation of highly specific targeting molecules into the viral capsid can potentially retarget adenoviral infection. However, conventional antibodies are not compatible with the cytoplasmic adenovirus capsid synthesis. The goal of this study was to evaluate the utility of single variable domains derived from heavy chain camelid antibodies for retargeting of adenovirus infection. We have combined transcriptional targeting using a tumor-specific promoter with transductional targeting through viral capsid incorporation of antihuman carcinoembryonic antigen single variable domains. Obtained data demonstrated that employment of a single variable domain genetically incorporated into an adenovirus fiber increased specificity of infection and efficacy of replication of single variable domain-targeted oncolytic adenovirus. The double targeting, both transcriptional through the C-X-C chemokine receptor type 4 promoter and transductional using the single variable domain, is a promising means to improve the therapeutic index for these advanced generation conditionally replicative adenoviruses. A successful strategy to transductional retargeting of oncolytic adenovirus infection has not been shown before and therefore we believe this is the first employment of transductional targeting using single variable domains derived from heavy chain camelid antibodies to enhance specificity of conditionally replicative adenoviruses.

  13. Efficient colonization and therapy of human hepatocellular carcinoma (HCC using the oncolytic vaccinia virus strain GLV-1h68.

    Directory of Open Access Journals (Sweden)

    Ivaylo Gentschev

    Full Text Available Virotherapy using oncolytic vaccinia virus strains is one of the most promising new strategies for cancer therapy. In this study, we analyzed for the first time the therapeutic efficacy of the oncolytic vaccinia virus GLV-1h68 in two human hepatocellular carcinoma cell lines HuH7 and PLC/PRF/5 (PLC in cell culture and in tumor xenograft models. By viral proliferation assays and cell survival tests, we demonstrated that GLV-1h68 efficiently colonized, replicated in, and did lyse these cancer cells in culture. Experiments with HuH7 and PLC xenografts have revealed that a single intravenous injection (i.v. of mice with GLV-1h68 resulted in a significant reduction of primary tumor sizes compared to uninjected controls. In addition, replication of GLV-1h68 in tumor cells led to strong inflammatory and oncolytic effects resulting in intense infiltration of MHC class II-positive cells like neutrophils, macrophages, B cells and dendritic cells and in up-regulation of 13 pro-inflammatory cytokines. Furthermore, GLV-1h68 infection of PLC tumors inhibited the formation of hemorrhagic structures which occur naturally in PLC tumors. Interestingly, we found a strongly reduced vascular density in infected PLC tumors only, but not in the non-hemorrhagic HuH7 tumor model. These data demonstrate that the GLV-1h68 vaccinia virus may have an enormous potential for treatment of human hepatocellular carcinoma in man.

  14. Oncolytic Vesicular Stomatitis Virus as a Viro-Immunotherapy: Defeating Cancer with a “Hammer” and “Anvil”

    Directory of Open Access Journals (Sweden)

    Michael Karl Melzer

    2017-02-01

    Full Text Available Oncolytic viruses have gained much attention in recent years, due, not only to their ability to selectively replicate in and lyse tumor cells, but to their potential to stimulate antitumor immune responses directed against the tumor. Vesicular stomatitis virus (VSV, a negative-strand RNA virus, is under intense development as an oncolytic virus due to a variety of favorable properties, including its rapid replication kinetics, inherent tumor specificity, and its potential to elicit a broad range of immunomodulatory responses to break immune tolerance in the tumor microenvironment. Based on this powerful platform, a multitude of strategies have been applied to further improve the immune-stimulating potential of VSV and synergize these responses with the direct oncolytic effect. These strategies include: 1. modification of endogenous virus genes to stimulate interferon induction; 2. virus-mediated expression of cytokines or immune-stimulatory molecules to enhance anti-tumor immune responses; 3. vaccination approaches to stimulate adaptive immune responses against a tumor antigen; 4. combination with adoptive immune cell therapy for potentially synergistic therapeutic responses. A summary of these approaches will be presented in this review.

  15. Effects of capsid-modified oncolytic adenoviruses and their combinations with gemcitabine or silica gel on pancreatic cancer.

    Science.gov (United States)

    Kangasniemi, Lotta; Parviainen, Suvi; Pisto, Tommi; Koskinen, Mika; Jokinen, Mika; Kiviluoto, Tuula; Cerullo, Vincenzo; Jalonen, Harry; Koski, Anniina; Kangasniemi, Anna; Kanerva, Anna; Pesonen, Sari; Hemminki, Akseli

    2012-07-01

    Conventional cancer treatments often have little impact on the course of advanced pancreatic cancer. Although cancer gene therapy with adenoviruses is a promising developmental approach, the primary receptor is poorly expressed in pancreatic cancers which might compromise efficacy and thus targeting to other receptors could be beneficial. Extended stealth delivery, combination with standard chemotherapy or circumvention of host antiadenoviral immune response might improve efficacy further. In this work, capsid-modified adenoviruses were studied for transduction of cell lines and clinical normal and tumor tissue samples. The respective oncolytic viruses were tested for oncolytic activity in vitro and in vivo. Survival was studied in a peritoneally disseminated pancreas cancer model, with or without concurrent gemcitabine while silica implants were utilized for extended intraperitoneal virus delivery. Immunocompetent mice and Syrian hamsters were used to study the effect of silica mediated delivery on antiviral immune responses and subsequent in vivo gene delivery. Capsid modifications selectively enhanced gene transfer to malignant pancreatic cancer cell lines and clinical samples. The respective oncolytic viruses resulted in increased cell killing in vitro, which translated into a survival benefit in mice. Early proinfammatory cytokine responses and formation of antiviral neutralizing antibodies was partially avoided with silica implants. The implant also shielded the virus from pre-existing neutralizing antibodies, while increasing the pancreas/liver gene delivery ratio six-fold. In conclusion, capsid modified adenoviruses would be useful for testing in pancreatic cancer trials. Silica implants might increase the safety and efficacy of the approach.

  16. Survivin promoter-regulated oncolytic adenovirus with Hsp70 gene exerts effective antitumor efficacy in gastric cancer immunotherapy.

    Science.gov (United States)

    Wang, Weiguo; Ji, Weidan; Hu, Huanzhang; Ma, Juming; Li, Xiaoya; Mei, Weiqun; Xu, Yang; Hu, Huizhen; Yan, Yan; Song, Qizhe; Li, Zhigang; Su, Changqing

    2014-01-15

    Gene therapy is a promising adjuvant therapeutic strategy for cancer treatment. To overcome the limitations of current gene therapy, such as poor transfection efficiency of vectors, low levels of transgene expression and lack of tumor targeting, the Survivin promoter was used to regulate the selective replication of oncolytic adenovirus in tumor cells, and the heat shock protein 70 (Hsp70) gene was loaded as the anticancer transgene to generate an AdSurp-Hsp70 viral therapy system. The efficacy of this targeted immunotherapy was examined in gastric cancer. The experiments showed that the oncolytic adenovirus can selectively replicate in and lyse the Survivin-positive gastric cancer cells, without significant toxicity to normal cells. AdSurp-Hsp70 reduced viability of cancer cells and inhibited tumor growth of gastric cancer xenografts in immuno-deficient and immuno-reconstruction mouse models. AdSurp-Hsp70 produced dual antitumor effects due to viral replication and high Hsp70 expression. This therapeutic system used the Survivin promoter-regulated oncolytic adenovirus vector to mediate targeted expression of the Hsp70 gene and ensure safety and efficacy for subsequent gene therapy programs against a variety of cancers.

  17. Photonic Crystal Fiber Attenuator

    Institute of Scientific and Technical Information of China (English)

    Joo; Beom; Eom; Hokyung; Kim; Jinchae; Kim; Un-Chul; Paek; Byeong; Ha; Lee

    2003-01-01

    We propose a novel fiber attenuator based on photonic crystal fibers. The difference in the modal field diameters of a conventional single mode fiber and a photonic crystal fiber was used. A variable optical attenuator was also achieved by applying macro-bending on the PCF part of the proposed attenuator

  18. Recombinant Technology and Probiotics

    Directory of Open Access Journals (Sweden)

    Icy D’Silva

    2011-09-01

    Full Text Available Recombinant technology has led the way to monumental advances in the development of useful molecules, including the development of safe probiotics. The development of novel approaches using recombinant technology and probiotics that allow accurate targeting of therapeutics to the mucosa is an interesting area of research. The creation and use of recombinant probiotics expressing recombinantovalbumin, recombinant ovalbumin mutants and yet-to-be-designed recombinant hypo/non-allergenic molecules offer the opportunity to further investigate their effects for food, nutrition, environment andhealth. This review highlights advances in native probiotics and recombinant probiotics expressing native and recombinant molecules for food, nutrition, environment and health.

  19. Recombinant Technology and Probiotics

    OpenAIRE

    Icy D’Silva

    2011-01-01

    Recombinant technology has led the way to monumental advances in the development of useful molecules, including the development of safe probiotics. The development of novel approaches using recombinant technology and probiotics that allow accurate targeting of therapeutics to the mucosa is an interesting area of research. The creation and use of recombinant probiotics expressing recombinantovalbumin, recombinant ovalbumin mutants and yet-to-be-designed recombinant hypo/non-allergenic molecule...

  20. Tracer attenuation in groundwater

    Science.gov (United States)

    Cvetkovic, Vladimir

    2011-12-01

    The self-purifying capacity of aquifers strongly depends on the attenuation of waterborne contaminants, i.e., irreversible loss of contaminant mass on a given scale as a result of coupled transport and transformation processes. A general formulation of tracer attenuation in groundwater is presented. Basic sensitivities of attenuation to macrodispersion and retention are illustrated for a few typical retention mechanisms. Tracer recovery is suggested as an experimental proxy for attenuation. Unique experimental data of tracer recovery in crystalline rock compare favorably with the theoretical model that is based on diffusion-controlled retention. Non-Fickian hydrodynamic transport has potentially a large impact on field-scale attenuation of dissolved contaminants.

  1. Cavitation-enhanced delivery of a replicating oncolytic adenovirus to tumors using focused ultrasound.

    Science.gov (United States)

    Bazan-Peregrino, Miriam; Rifai, Bassel; Carlisle, Robert C; Choi, James; Arvanitis, Costas D; Seymour, Leonard W; Coussios, Constantin C

    2013-07-10

    Oncolytic viruses (OV) and ultrasound-enhanced drug delivery are powerful novel technologies. OV selectively self-amplify and kill cancer cells but their clinical use has been restricted by limited delivery from the bloodstream into the tumor. Ultrasound has been previously exploited for targeted release of OV in vivo, but its use to induce cavitation, microbubble oscillations, for enhanced OV tumor extravasation and delivery has not been previously reported. By identifying and optimizing the underlying physical mechanism, this work demonstrates that focused ultrasound significantly enhances the delivery and biodistribution of systemically administered OV co-injected with microbubbles. Up to a fiftyfold increase in tumor transgene expression was achieved, without any observable tissue damage. Ultrasound exposure parameters were optimized as a function of tumor reperfusion time to sustain inertial cavitation, a type of microbubble activity, throughout the exposure. Passive detection of acoustic emissions during treatment confirmed inertial cavitation as the mechanism responsible for enhanced delivery and enabled real-time monitoring of successful viral delivery.

  2. Preclinical Evaluation of Engineered Oncolytic Herpes Simplex Virus for the Treatment of Neuroblastoma

    Science.gov (United States)

    Gillory, Lauren A.; Megison, Michael L.; Stewart, Jerry E.; Mroczek-Musulman, Elizabeth; Nabers, Hugh C.; Waters, Alicia M.; Kelly, Virginia; Coleman, Jennifer M.; Markert, James M.; Gillespie, G. Yancey; Friedman, Gregory K.; Beierle, Elizabeth A.

    2013-01-01

    Despite intensive research efforts and therapeutic advances over the last few decades, the pediatric neural crest tumor, neuroblastoma, continues to be responsible for over 15% of pediatric cancer deaths. Novel therapeutic options are needed for this tumor. Recently, investigators have shown that mice with syngeneic murine gliomas treated with an engineered, neuroattenuated oncolytic herpes simplex virus-1 (oHSV), M002, had a significant increase in survival. M002 has deletions in both copies of the γ134.5 gene, enabling replication in tumor cells but precluding infection of normal neural cells. We hypothesized that M002 would also be effective in the neural crest tumor, neuroblastoma. We showed that M002 infected, replicated, and decreased survival in neuroblastoma cell lines. In addition, we showed that in murine xenografts, treatment with M002 significantly decreased tumor growth, and that this effect was augmented with the addition of ionizing radiation. Importantly, survival could be increased by subsequent doses of radiation without re-dosing of the virus. Finally, these studies showed that the primary entry protein for oHSV, CD111 was expressed by numerous neuroblastoma cell lines and was also present in human neuroblastoma specimens. We concluded that M002 effectively targeted neuroblastoma and that this oHSV may have potential for use in children with unresponsive or relapsed neuroblastoma. PMID:24130898

  3. Preclinical evaluation of engineered oncolytic herpes simplex virus for the treatment of neuroblastoma.

    Directory of Open Access Journals (Sweden)

    Lauren A Gillory

    Full Text Available Despite intensive research efforts and therapeutic advances over the last few decades, the pediatric neural crest tumor, neuroblastoma, continues to be responsible for over 15% of pediatric cancer deaths. Novel therapeutic options are needed for this tumor. Recently, investigators have shown that mice with syngeneic murine gliomas treated with an engineered, neuroattenuated oncolytic herpes simplex virus-1 (oHSV, M002, had a significant increase in survival. M002 has deletions in both copies of the γ 1 34.5 gene, enabling replication in tumor cells but precluding infection of normal neural cells. We hypothesized that M002 would also be effective in the neural crest tumor, neuroblastoma. We showed that M002 infected, replicated, and decreased survival in neuroblastoma cell lines. In addition, we showed that in murine xenografts, treatment with M002 significantly decreased tumor growth, and that this effect was augmented with the addition of ionizing radiation. Importantly, survival could be increased by subsequent doses of radiation without re-dosing of the virus. Finally, these studies showed that the primary entry protein for oHSV, CD111 was expressed by numerous neuroblastoma cell lines and was also present in human neuroblastoma specimens. We concluded that M002 effectively targeted neuroblastoma and that this oHSV may have potential for use in children with unresponsive or relapsed neuroblastoma.

  4. Oncolytic Immunotherapy: Dying the Right Way is a Key to Eliciting Potent Antitumor Immunity

    Directory of Open Access Journals (Sweden)

    Zong Sheng eGuo

    2014-04-01

    Full Text Available Oncolytic viruses (OVs are novel immunotherapeutic agents whose anticancer effects come from both oncolysis and elicited antitumor immunity. OVs induce mostly immunogenic cancer cell death (ICD, including immunogenic apoptosis, necrosis/necroptosis, pyroptosis and autophagic cell death, leading to exposure of calreticulin and heat-shock proteins to the cell surface, and/or released ATP, high mobility group box-1 [HMGB1], uric acid, and other DAMPs as well as PAMPs as danger signals, along with tumor-associated antigens, to activate dendritic cells (DCs and elicit adaptive antitumor immunity. Dying the right way may greatly potentiate adaptive antitumor immunity. The mode of cancer cell death may be modulated by individual OVs and cancer cells as they often encode and express genes that inhibit/promote apoptosis, necroptosis or autophagic cell death. We can genetically engineer OVs with death-pathway-modulating genes and thus skew the infected cancer cells towards certain death pathways for the enhanced immunogenicity. Strategies combining with some standard therapeutic regimens may also change the immunological consequence of cancer cell death. In this review, we discuss recent advances in our understanding of danger signals, modes of cancer cell death induced by OVs, the induced danger signals and functions in eliciting subsequent antitumor immunity. We also discuss potential combination strategies to target cells into specific modes of ICD and enhance cancer immunogenicity, including blockade of immune checkpoints, in order to break immune tolerance, improve antitumor immunity and thus the overall therapeutic efficacy.

  5. Antigen profiling analysis of vaccinia virus injected canine tumors: oncolytic virus efficiency predicted by boolean models.

    Science.gov (United States)

    Cecil, Alexander; Gentschev, Ivaylo; Adelfinger, Marion; Nolte, Ingo; Dandekar, Thomas; Szalay, Aladar A

    2014-01-01

    Virotherapy on the basis of oncolytic vaccinia virus (VACV) strains is a novel approach for cancer therapy. In this study we describe for the first time the use of dynamic boolean modeling for tumor growth prediction of vaccinia virus GLV-1h68-injected canine tumors including canine mammary adenoma (ZMTH3), canine mammary carcinoma (MTH52c), canine prostate carcinoma (CT1258), and canine soft tissue sarcoma (STSA-1). Additionally, the STSA-1 xenografted mice were injected with either LIVP 1.1.1 or LIVP 5.1.1 vaccinia virus strains.   Antigen profiling data of the four different vaccinia virus-injected canine tumors were obtained, analyzed and used to calculate differences in the tumor growth signaling network by type and tumor type. Our model combines networks for apoptosis, MAPK, p53, WNT, Hedgehog, TK cell, Interferon, and Interleukin signaling networks. The in silico findings conform with in vivo findings of tumor growth. Boolean modeling describes tumor growth and remission semi-quantitatively with a good fit to the data obtained for all cancer type variants. At the same time it monitors all signaling activities as a basis for treatment planning according to antigen levels. Mitigation and elimination of VACV- susceptible tumor types as well as effects on the non-susceptible type CT1258 are predicted correctly. Thus the combination of Antigen profiling and semi-quantitative modeling optimizes the therapy already before its start.

  6. Histone deacetylase inhibitors improve the replication of oncolytic herpes simplex virus in breast cancer cells.

    Directory of Open Access Journals (Sweden)

    James J Cody

    Full Text Available New therapies are needed for metastatic breast cancer patients. Oncolytic herpes simplex virus (oHSV is an exciting therapy being developed for use against aggressive tumors and established metastases. Although oHSV have been demonstrated safe in clinical trials, a lack of sufficient potency has slowed the clinical application of this approach. We utilized histone deacetylase (HDAC inhibitors, which have been noted to impair the innate antiviral response and improve gene transcription from viral vectors, to enhance the replication of oHSV in breast cancer cells. A panel of chemically diverse HDAC inhibitors were tested at three different doses (LD50 for their ability to modulate the replication of oHSV in breast cancer cells. Several of the tested HDAC inhibitors enhanced oHSV replication at low multiplicity of infection (MOI following pre-treatment of the metastatic breast cancer cell line MDA-MB-231 and the oHSV-resistant cell line 4T1, but not in the normal breast epithelial cell line MCF10A. Inhibitors of class I HDACs, including pan-selective compounds, were more effective for increasing oHSV replication compared to inhibitors that selectively target class II HDACs. These studies demonstrate that select HDAC inhibitors increase oHSV replication in breast cancer cells and provides support for pre-clinical evaluation of this combination strategy.

  7. Immune response is an important aspect of the antitumor effect produced by a CD40L-encoding oncolytic adenovirus.

    Science.gov (United States)

    Diaconu, Iulia; Cerullo, Vincenzo; Hirvinen, Mari L M; Escutenaire, Sophie; Ugolini, Matteo; Pesonen, Saila K; Bramante, Simona; Parviainen, Suvi; Kanerva, Anna; Loskog, Angelica S I; Eliopoulos, Aristides G; Pesonen, Sari; Hemminki, Akseli

    2012-05-01

    Oncolytic adenovirus is an attractive platform for immunotherapy because virus replication is highly immunogenic and not subject to tolerance. Although oncolysis releases tumor epitopes and provides costimulatory danger signals, arming the virus with immunostimulatory molecules can further improve efficacy. CD40 ligand (CD40L, CD154) induces apoptosis of tumor cells and triggers several immune mechanisms, including a T-helper type 1 (T(H)1) response, which leads to activation of cytotoxic T cells and reduction of immunosuppression. In this study, we constructed a novel oncolytic adenovirus, Ad5/3-hTERT-E1A-hCD40L, which features a chimeric Ad5/3 capsid for enhanced tumor transduction, a human telomerase reverse transcriptase (hTERT) promoter for tumor selectivity, and human CD40L for increased efficacy. Ad5/3-hTERT-E1A-hCD40L significantly inhibited tumor growth in vivo via oncolytic and apoptotic effects, and (Ad5/3-hTERT-E1A-hCD40L)-mediated oncolysis resulted in enhanced calreticulin exposure and HMGB1 and ATP release, which were suggestive of immunogenicity. In two syngeneic mouse models, murine CD40L induced recruitment and activation of antigen-presenting cells, leading to increased interleukin-12 production in splenocytes. This effect was associated with induction of the T(H)1 cytokines IFN-γ, RANTES, and TNF-α. Tumors treated with Ad5/3-CMV-mCD40L also displayed an enhanced presence of macrophages and cytotoxic CD8(+) T cells but not B cells. Together, our findings show that adenoviruses coding for CD40L mediate multiple antitumor effects including oncolysis, apoptosis, induction of T-cell responses, and upregulation of T(H)1 cytokines.

  8. Therapeutic Recombinant Monoclonal Antibodies

    Science.gov (United States)

    Bakhtiar, Ray

    2012-01-01

    During the last two decades, the rapid growth of biotechnology-derived techniques has led to a myriad of therapeutic recombinant monoclonal antibodies with significant clinical benefits. Recombinant monoclonal antibodies can be obtained from a number of natural sources such as animal cell cultures using recombinant DNA engineering. In contrast to…

  9. 77 FR 22333 - Prospective Grant of Exclusive License: Development of Oncolytic Viral Cancer Therapies

    Science.gov (United States)

    2012-04-13

    ...: Notice. SUMMARY: This is notice, in accordance with 35 U.S.C. 209(c)(1) and 37 CFR Part 404.7(a)(1)(i...: 1. U.S. Patent No. 7,045,313 issued May 16, 2006 entitled, ``Recombinant Vaccinia Virus Containing a... recombinant poxviruses, and in particular the vaccinia virus, as a backbone that carries a foreign DNA....

  10. Efficacy and safety/toxicity study of recombinant vaccinia virus JX-594 in two immunocompetent animal models of glioma.

    Science.gov (United States)

    Lun, XueQing; Chan, Jennifer; Zhou, Hongyuan; Sun, Beichen; Kelly, John J P; Stechishin, Owen Owen; Bell, John C; Parato, Kelley; Hu, Kang; Vaillant, Dominique; Wang, Jiahu; Liu, Ta-Chiang; Breitbach, Caroline; Kirn, David; Senger, Donna L; Forsyth, Peter A

    2010-11-01

    The purpose of this study was to investigate the oncolytic potential of the recombinant, granulocyte macrophage colony-stimulating factor (GM-CSF)-expressing vaccinia virus (VV) JX-594 in experimental malignant glioma (MGs) in vitro and in immunocompetent rodent models. We have found that JX-594 killed all MG cell lines tested in vitro. Intratumoral (i.t.) administration of JX-594 significantly inhibited tumor growth and prolonged survival in rats-bearing RG2 intracranial (i.c.) tumors and mice-bearing GL261 brain tumors. Combination therapy with JX-594 and rapamycin significantly increased viral replication and further prolonged survival in both immunocompetent i.c. MG models with several animals considered "cured" (three out of seven rats >120 days, terminated experiment). JX-594 infected and killed brain tumor-initiating cells (BTICs) from patient samples grown ex vivo, and did so more efficiently than other oncolytic viruses MYXV, Reovirus type-3, and VSV(ΔM51). Additional safety/toxicity studies in nontumor-bearing rodents treated with a supratherapeutic dose of JX-594 demonstrated GM-CSF-dependent inflammation and necrosis. These results suggest that i.c. administered JX-594 triggers a predictable GM-CSF-mediated inflammation in murine models. Before proceeding to clinical trials, JX-594 should be evaluated in the brains of nonhuman primates and optimized for the viral doses, delivery routes as well as the combination agents (e.g., mTOR inhibitors).

  11. Human precision-cut liver tumor slices as a tumor patient-individual predictive test system for oncolytic measles vaccine viruses

    NARCIS (Netherlands)

    Zimmermann, Martina; Armeanu, Sorin; Smirnow, Irina; Kupka, Susan; Wagner, Silvia; Wehrmann, Manfred; Rots, Marianne G.; Groothuis, Geny M. M.; Weiss, Thomas S.; Koenigsrainer, Alfred; Gregor, Michael; Bitzer, Michael; Lauer, Ulrich M.

    2009-01-01

    Availability of an individualized preselection of oncolytic viruses to be used for virotherapy of tumor patients would be of great help. Using primary liver tumor resection specimens we evaluated the precision-cut liver slice (PCLS) technology as a novel in vitro test system for characterization of

  12. A modified hTERT promoter-directed oncolytic adenovirus replication with concurrent inhibition of TGFbeta signaling for breast cancer therapy.

    Science.gov (United States)

    Hu, Z; Robbins, J S; Pister, A; Zafar, M B; Zhang, Z-W; Gupta, J; Lee, K J; Newman, K; Neuman, K; Yun, C-O; Guise, T; Seth, P

    2010-04-01

    We were interested in developing oncolytic adenoviral vectors that can be administered systemically for the treatment of breast cancer. To restrict viral replication in breast tumor cells, we constructed mhTERTAd.sTbetaRFc, a 01/07-based adenoviral vector expressing the soluble form of transforming growth factor-beta (TGFbeta) receptor II fused with the human Fc IgG1 (sTGFbetaRIIFc) gene, in which viral replication is under the control of a modified human telomerase reverse transcriptase (mhTERT) promoter. In addition, mhTERTAd.sTbetaRFc-mediated sTGFbetaRIIFc production targets the TGFbeta pathway known to contribute to the tumor progression of breast cancer metastasis. We chose to use the mhTERT promoter because it was found to be relatively more active (approximately 20 times) in breast cancer cells compared with normal human cells. We showed that infection of MDA-MB-231 and MCF-7 breast cancer cells for 48 h with mhTERTAd.sTbetaRFc produced high levels of sTGFbetaRIIFc (greater than 1 microg ml(-1)) in the medium. Breast cancer cells produced nearly a 6000-fold increase in viral titers during the 48 h infection period. However, mhTERTAd.sTbetaRFc replication was attenuated in normal cells. Infection of breast cancer cells with a replication-deficient virus Ad(E1(-)).sTbetaRFc also produced high levels of sTGFbetaRIIFc, but under these conditions, no detectable viral replication was observed. Adenoviral-mediated production of sTGFbetaRIIFc was shown to bind with TGFbeta-1, and to abolish the effects of TGFbeta-1 on downstream SMAD-3 phosphorylation. The administration of mhTERTAd.sTbetaRFc intravenously into MDA-MB-231 human xenograft-bearing mice resulted in a significant inhibition of tumor growth and production of sTGFbetaRIIFc in the blood. Conversely, intravenous injection of Ad(E1(-)).sTbetaRFc did not show a significant inhibition of tumor growth, but resulted in sTGFbetaRIIFc in the blood, suggesting that viral replication along with s

  13. A modified hTERT Promoter-directed Oncolytic Adenovirus Replication with Concurrent Inhibition of TGFβ Signaling for Breast Cancer Therapy

    Science.gov (United States)

    Hu, Zebin; Robbins, John S.; Pister, Amanda; Zafar, M. Behzad; Zhang, Zhen-Wei; Gupta, Janhavi; Lee, K. Jessica; Neuman, Kam; Yun, Chae-Ok; Guise, Theresa; Seth, Prem

    2009-01-01

    Our laboratory is interested to develop oncolytic adenoviral vectors that can be administered systemically for the treatment of breast cancer. To restrict viral replication in breast tumor cells, we have constructed mhTERTAd.sTβRFc, a 01/07 based adenoviral vector expressing the soluble form of TGFβ receptor II fused with human Fc IgG1 (sTGFβRIIFc) gene, in which viral replication is under the control of modified human telomerase reverse transcriptase (mhTERT) promoter. In addition, mhTERTAd.sTβRFc-mediated sTGFβRIIFc production would target growth factor-β (TGFβ) pathway known to contribute to the tumor progression breast cancer metastasis. We chose to use mhTERT promoter because it was found to be relatively more active (approximately 20-times) in breast cancer cells compared to normal human cells. We showed that infection of MDA-MB-231 and MCF-7 breast cancer cells for 48 hrs with mhTERTAd.sTβRFc produced high levels of sTGFβRIIFc (greater than 1 μg/ml) in the medium. Breast cancer cells produced nearly 6,000-fold increase in the viral titers during 48 hrs infection period. However, mhTERTAd.sTβRFc replication was attenuated in normal cells. Infection of breast cancer cells with a replication deficient virus Ad(E1-).sTβRFc also produced high levels of sTGFβRIIFc, but under these conditions no detectable viral replication was observed. Adenoviral-mediated production of sTGFβRIIFc was shown to bind with TGFβ-1, and abolished the effects of TGFβ-1 on downstream SMAD-3 phosphorylation. The administration of mhTERTAd.sTβRFc intravenously into MDA-MB-231 human xenograft bearing mice resulted in significant inhibition of tumor growth, and production of sTGFβRIIFc in the blood. On the other hand, intravenous injection of Ad(E1-).sTβRFc did not exhibit significant inhibition of the tumor growth, but resulted in the sTGFβRIIFc in the blood, suggesting that viral replication along with sTGFβRIIFc protein production play a critical role in inducing

  14. Systemic Delivery of an Oncolytic Adenovirus Expressing Decorin for the Treatment of Breast Cancer Bone Metastases.

    Science.gov (United States)

    Yang, Yuefeng; Xu, Weidong; Neill, Thomas; Hu, Zebin; Wang, Chi-Hsiung; Xiao, Xianghui; Stock, Stuart R; Guise, Theresa; Yun, Chae-Ok; Brendler, Charles B; Iozzo, Renato V; Seth, Prem

    2015-12-01

    The development of novel therapies for breast cancer bone metastasis is a major unmet medical need. Toward that end, we have constructed an oncolytic adenovirus, Ad.dcn, and a nonreplicating adenovirus, Ad(E1-).dcn, both containing the human decorin gene. Our in vitro studies showed that Ad.dcn produced high levels of viral replication and the decorin protein in the breast tumor cells. Ad(E1-).dcn-mediated decorin expression in MDA-MB-231 cells downregulated the expression of Met, β-catenin, and vascular endothelial growth factor A, all of which are recognized decorin targets and play pivotal roles in the progression of breast tumor growth and metastasis. Adenoviral-mediated decorin expression inhibited cell migration and induced mitochondrial autophagy in MDA-MB-231 cells. Mice bearing MDA-MB-231-luc skeletal metastases were systemically administered with the viral vectors, and skeletal tumor growth was monitored over time. The results of bioluminescence imaging and X-ray radiography indicated that Ad.dcn and Ad(E1-).dcn significantly inhibited the progression of bone metastases. At the terminal time point, histomorphometric analysis, micro-computed tomography, and bone destruction biomarkers showed that Ad.dcn and Ad(E1-).dcn reduced tumor burden and inhibited bone destruction. A nonreplicating adenovirus Ad(E1-).luc expressing the luciferase 2 gene had no significant effect on inhibiting bone metastases, and in several assays, Ad.dcn and Ad(E1-).dcn were better than Ad.luc, a replicating virus expressing the luciferase 2 gene. Our data suggest that adenoviral replication coupled with decorin expression could produce effective antitumor responses in a MDA-MB-231 bone metastasis model of breast cancer. Thus, Ad.dcn could potentially be developed as a candidate gene therapy vector for treating breast cancer bone metastases.

  15. Myxoma virus sensitizes cancer cells to gemcitabine and is an effective oncolytic virotherapeutic in models of disseminated pancreatic cancer.

    Science.gov (United States)

    Wennier, Sonia Tusell; Liu, Jia; Li, Shoudong; Rahman, Masmudur M; Mona, Mahmoud; McFadden, Grant

    2012-04-01

    Myxoma virus (MYXV) is a novel oncolytic virus that has been shown to replicate in pancreatic cancer cells, but its efficacy in animal models of pancreatic cancer has not been determined. The efficacy of MYXV as monotherapy or in combination with gemcitabine was evaluated in intraperitoneal dissemination (IPD) models of pancreatic cancer. The effects of an intact immune system on the efficacy of MYXV therapy was tested by comparing immunodeficient versus immunocompetent murine models and combination therapy with gemcitabine was also evaluated. In cell culture, MYXV replication was robust in a broad range of pancreatic cancer cells and also showed increased oncolysis in combination with gemcitabine. In animal models, MYXV treatment conferred survival benefits over control or gemcitabine-treated cohorts regardless of the cell line or animal model used. MYXV monotherapy was most effective in an immunocompetent IPD model, and resulted in 60% long-term survivors. In Pan02 engrafted immunocompetent IPD models, sequential treatment in which MYXV was administered first, followed by gemcitabine, was the most effective and resulted in 100% long-term survivors. MYXV is an effective oncolytic virus for pancreatic cancer and can be combined with gemcitabine to enhance survival, particularly in the presence of an intact host immune system.

  16. Prevention of EBV lymphoma development by oncolytic myxoma virus in a murine xenograft model of post-transplant lymphoproliferative disease

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Manbok, E-mail: manbok66@dankook.ac.kr [Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610 (United States); Rahman, Masmudur M. [Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610 (United States); Cogle, Christopher R. [Department of Hematology/Oncology, University of Florida, Gainesville, FL 32610 (United States); McFadden, Grant [Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610 (United States)

    2015-07-10

    Epstein–Barr virus (EBV) has been associated with a variety of epithelial and hematologic malignancies, including B-, T- and NK cell-lymphomas, Hodgkin's disease (HD), post-transplant lymphoproliferative diseases (LPDs), nasopharyngeal and gastric carcinomas, smooth muscle tumors, and HIV-associated lymphomas. Currently, treatment options for EBV-associated malignancies are limited. We have previously shown that myxoma virus specifically targets various human solid tumors and leukemia cells in a variety of animal models, while sparing normal human or murine tissues. Since transplant recipients of bone marrow or solid organs often develop EBV-associated post-transplant LPDs and lymphoma, myxoma virus may be of utility to prevent EBV-associated malignancies in immunocompromised transplant patients where treatment options are frequently limited. In this report, we demonstrate the safety and efficacy of myxoma virus purging as a prophylactic strategy for preventing post-transplant EBV-transformed human lymphomas, using a highly immunosuppressed mouse xenotransplantation model. This provides support for developing myxoma virus as a potential oncolytic therapy for preventing EBV-associated LPDs following transplantation of bone marrow or solid organ allografts. - Highlights: • Myxoma virus effectively infects and purges EBV lymphoma cells in vivo. • Oncolytic myxoma virus effectively eradicates oncogenic EBV tumorigenesis. • Ex vivo pre-treatment of myxoma virus can be effective as a preventive treatment modality for post-transplant lymphoproliferative diseases.

  17. Oral Immunization with Recombinant Listeria monocytogenes Controls Virus Load after Vaginal Challenge with Feline Immunodeficiency Virus

    OpenAIRE

    Stevens, Rosemary; Howard, Kristina E.; Nordone, Sushila; Burkhard, MaryJo; Dean, Gregg A

    2004-01-01

    Recombinant Listeria monocytogenes has many attractive characteristics as a vaccine vector against human immunodeficiency virus (HIV). Wild-type and attenuated Listeria strains expressing HIV Gag have been shown to induce long-lived mucosal and systemic T-cell responses in mice. Using the feline immunodeficiency virus (FIV) model of HIV we evaluated recombinant L. monocytogenes in a challenge system. Five cats were immunized with recombinant L. monocytogenes that expresses the FIV Gag and del...

  18. Landing gear noise attenuation

    Science.gov (United States)

    Moe, Jeffrey W. (Inventor); Whitmire, Julia (Inventor); Kwan, Hwa-Wan (Inventor); Abeysinghe, Amal (Inventor)

    2011-01-01

    A landing gear noise attenuator mitigates noise generated by airframe deployable landing gear. The noise attenuator can have a first position when the landing gear is in its deployed or down position, and a second position when the landing gear is in its up or stowed position. The noise attenuator may be an inflatable fairing that does not compromise limited space constraints associated with landing gear retraction and stowage. A truck fairing mounted under a truck beam can have a compliant edge to allow for non-destructive impingement of a deflected fire during certain conditions.

  19. Recombinant MVA vaccines: dispelling the myths.

    Science.gov (United States)

    Cottingham, Matthew G; Carroll, Miles W

    2013-09-06

    Diseases such as HIV/AIDS, tuberculosis, malaria and cancer are prime targets for prophylactic or therapeutic vaccination, but have proven partially or wholly resistant to traditional approaches to vaccine design. New vaccines based on recombinant viral vectors expressing a foreign antigen are under intense development for these and other indications. One of the most advanced and most promising vectors is the attenuated, non-replicating poxvirus MVA (modified vaccinia virus Ankara), a safer derivative of the uniquely successful smallpox vaccine. Despite the ability of recombinant MVA to induce potent humoral and cellular immune responses against transgenic antigen in humans, especially when used as the latter element of a heterologous prime-boost regimen, doubts are occasionally expressed about the ultimate feasibility of this approach. In this review, five common misconceptions over recombinant MVA are discussed, and evidence is cited to show that recombinant MVA is at least sufficiently genetically stable, manufacturable, safe, and immunogenic (even in the face of prior anti-vector immunity) to warrant reasonable hope over the feasibility of large-scale deployment, should useful levels of protection against target pathogens, or therapeutic benefit for cancer, be demonstrated in efficacy trials.

  20. Planetary Ices Attenuation Properties

    Science.gov (United States)

    McCarthy, Christine; Castillo-Rogez, Julie C.

    In this chapter, we review the topic of energy dissipation in the context of icy satellites experiencing tidal forcing. We describe the physics of mechanical dissipation, also known as attenuation, in polycrystalline ice and discuss the history of laboratory methods used to measure and understand it. Because many factors - such as microstructure, composition and defect state - can influence rheological behavior, we review what is known about the mechanisms responsible for attenuation in ice and what can be inferred from the properties of rocks, metals and ceramics. Since attenuation measured in the laboratory must be carefully scaled to geologic time and to planetary conditions in order to provide realistic extrapolation, we discuss various mechanical models that have been used, with varying degrees of success, to describe attenuation as a function of forcing frequency and temperature. We review the literature in which these models have been used to describe dissipation in the moons of Jupiter and Saturn. Finally, we address gaps in our present knowledge of planetary ice attenuation and provide suggestions for future inquiry.

  1. FDG-PET/CT for Monitoring Response of Melanoma to the Novel Oncolytic Viral Therapy Talimogene Laherparepvec.

    Science.gov (United States)

    Covington, Matthew F; Curiel, Clara N; Lattimore, Lois; Avery, Ryan J; Kuo, Phillip H

    2017-02-01

    61-year-old woman with stage IIIa (T3a N1a M0) left lower leg melanoma with lesions suggestive of in-transit metastases 8 months following wide local excision and femoral nodal dissection. FDG-PET/CT demonstrated 5 FDG-avid in-transit nodal metastases in the distal left leg, confirmed on biopsy. Talimogene laherparepvec (T-VEC) oncolytic immunotherapy consisting of intralesional injections of modified herpes simplex virus-expressing granulocyte-macrophage colony-stimulating factor was completed over 6 months. Subsequent FDG-PET/CT demonstrated reduced or resolved FDG activity in the treated in-transit metastases and a new FDG-avid left thigh in-transit metastasis. FDG-PET/CT can monitor response to T-VEC and potentially other novel viral immunotherapies.

  2. Interview with Robert Coffin, inventor of T-VEC: the first oncolytic immunotherapy approved for the treatment of cancer.

    Science.gov (United States)

    Coffin, Robert

    2016-02-01

    Interviewed by Ellen Clarke, Commissioning Editor, Future Science Group. Robert Coffin is co-founder and CEO of Replimune. Previously he was Founder and CTO of BioVex Inc, a spin out from his research group at University College London in 1999. He was the inventor of all BioVex products including OncoVEXGM-CSF (talimogene laherparepvec; T-VEC; Imlygic) and oversaw all research and clinical development including bringing T-VEC through to two pivotal Phase 3 studies in melanoma and head and neck cancer. BioVex was acquired by Amgen in 2011 where he was VP Global Development until 2013. T-VEC was approved by the FDA for use in advanced melanoma in October 2015, the first oncolytic therapy or gene therapy to be approved in USA. He was awarded a PhD in virology from Imperial College London prior to his move to University College London in 1991.

  3. ET-46ONCOLYTIC VIRAL THERAPY FOR MALIGNANT GLIOMAS USING MYXOMA VIRUS DELETED FOR ANTI-APOPTOTIC M11L GENE

    Science.gov (United States)

    Pisklakova, Alexandra; McKenzie, Brienne; Kenchappa, Rajappa; McFadden, Grant; Forsyth, Peter

    2014-01-01

    Brain Tumour Initiating Cells (BTICs) are stem-like cells hypothesized to mediate recurrence in high-grade gliomas. Myxoma virus (MyxV) is a promising oncolytic virus, which is highly effective in conventional long term resistant glioma cell lines and less effective in BTICs. We hypothesized that one possible factor limiting efficacy in BTICs is that cell death following infection with MyxV is inhibited by virally encoded anti-apoptotic proteins, such as the Bcl-2 structural homologue, M011L. To test this we evaluated and compared the efficacy of wtMYXV versus the viral construct MyxV-M011L-KO (in which the anti-apoptotic protein M11L has been deleted) in BTICs. We found that WT-MyxV does not induce significant level of apoptosis in infected BTICs, but that MyxV-M011L-KO induces dramatically more apoptosisas shown by caspase activation, PARP cleavage, and Cytochrome C release from the mitochondria M11L from the WT-MyxV localized to the mitochondrial membrane and prevented the association of Bax with the mitochondrial membrane. Finally, silencing of Bax using specific siRNAs significantly blocked the induction of apoptosis and cell death that occurs after infection with mutant MyxV-M011L-KO virus. Therefore MyxV-M011L-KO, which is has the anti-apoptotic virally derived gene M11L, dramatically improves the oncolytic efficacy in BTICs and this is dependent on the presence of the pro-apoptotic host protein, Bax. This is the first demonstration, that the MyxV mutant, genetically modified to promote apoptosis in tumor initiating cells, is significantly more efficacious than the wildtype virus. Strategies, such as this one, that promotes apoptosis in tumor initiating cells might be particularly effective.

  4. Treatment of medulloblastoma using an oncolytic measles virus encoding the thyroidal sodium iodide symporter shows enhanced efficacy with radioiodine

    Directory of Open Access Journals (Sweden)

    Hutzen Brian

    2012-11-01

    Full Text Available Abstract Background Medulloblastoma is the most common malignant brain tumor of childhood. Although the clinical outcome for medulloblastoma patients has improved significantly, children afflicted with the disease frequently suffer from debilitating side effects related to the aggressive nature of currently available therapy. Alternative means for treating medulloblastoma are desperately needed. We have previously shown that oncolytic measles virus (MV can selectively target and destroy medulloblastoma tumor cells in localized and disseminated models of the disease. MV-NIS, an oncolytic measles virus that encodes the human thyroidal sodium iodide symporter (NIS, has the potential to deliver targeted radiotherapy to the tumor site and promote a localized bystander effect above and beyond that achieved by MV alone. Methods We evaluated the efficacy of MV-NIS against medulloblastoma cells in vitro and examined their ability to incorporate radioiodine at various timepoints, finding peak uptake at 48 hours post infection. The effects of MV-NIS were also evaluated in mouse xenograft models of localized and disseminated medulloblastoma. Athymic nude mice were injected with D283med-Luc medulloblastoma cells in the caudate putamen (localized disease or right lateral ventricle (disseminated disease and subsequently treated with MV-NIS. Subsets of these mice were given a dose of 131I at 24, 48 or 72 hours later. Results MV-NIS treatment, both by itself and in combination with 131I, elicited tumor stabilization and regression in the treated mice and significantly extended their survival times. Mice given 131I were found to concentrate radioiodine at the site of their tumor implantations. In addition, mice with localized tumors that were given 131I either 24 or 48 hours after MV-NIS treatment exhibited a significant survival advantage over mice given MV-NIS alone. Conclusions These data suggest MV-NIS plus radioiodine may be a potentially useful therapy for

  5. Targeted cancer immunotherapy with oncolytic adenovirus coding for a fully human monoclonal antibody specific for CTLA-4.

    Science.gov (United States)

    Dias, J D; Hemminki, O; Diaconu, I; Hirvinen, M; Bonetti, A; Guse, K; Escutenaire, S; Kanerva, A; Pesonen, S; Löskog, A; Cerullo, V; Hemminki, A

    2012-10-01

    Promising clinical results have been achieved with monoclonal antibodies (mAbs) such as ipilimumab and tremelimumab that block cytotoxic T lymphocyte-associated antigen-4 (CTLA-4, CD152). However, systemic administration of these agents also has the potential for severe immune-related adverse events. Thus, local production might allow higher concentrations at the target while reducing systemic side effects. We generated a transductionally and transcriptionally targeted oncolytic adenovirus Ad5/3-Δ24aCTLA4 expressing complete human mAb specific for CTLA-4 and tested it in vitro, in vivo and in peripheral blood mononuclear cells (PBMCs) of normal donors and patients with advanced solid tumors. mAb expression was confirmed by western blotting and immunohistochemistry. Biological functionality was determined in a T-cell line and in PBMCs from cancer patients. T cells of patients, but not those of healthy donors, were activated by an anti-CTLA4mAb produced by Ad5/3-Δ24aCTLA4. In addition to immunological effects, a direct anti-CTLA-4-mediated pro-apoptotic effect was observed in vitro and in vivo. Local production resulted in 43-fold higher (P<0.05) tumor versus plasma anti-CTLA4mAb concentration. Plasma levels in mice remained below what has been reported safe in humans. Replication-competent Ad5/3-Δ24aCTLA4 resulted in 81-fold higher (P<0.05) tumor mAb levels as compared with a replication-deficient control. This is the first report of an oncolytic adenovirus producing a full-length human mAb. High mAb concentrations were seen at tumors with lower systemic levels. Stimulation of T cells of cancer patients by Ad5/3-Δ24aCTLA4 suggests feasibility of testing the approach in clinical trials.

  6. 11R-P53 and GM-CSF Expressing Oncolytic Adenovirus Target Cancer Stem Cells with Enhanced Synergistic Activity

    Science.gov (United States)

    Lv, Sai-qun; Ye, Zhen-long; Liu, Pin-yi; Huang, Yao; Li, Lin-fang; Liu, Hui; Zhu, Hai-li; Jin, Hua-jun; Qian, Qi-jun

    2017-01-01

    Targeting cancer stem cells with oncolytic virus (OV) holds great potential for thorough elimination of cancer cells. Based on our previous studies, we here established 11R-P53 and mGM-CSF carrying oncolytic adenovirus (OAV) SG655-mGMP and investigated its therapeutic effect on hepatocellular carcinoma stem cells Hep3B-C and teratoma stem cells ECCG5. Firstly, the augmenting effect of 11R in our construct was tested and confirmed by examining the expression of EGFP with Fluorescence and FCM assays after transfecting Hep3B-C and ECCG5 cells with OVA SG7605-EGFP and SG7605-11R-EGFP. Secondly, the expressions of 11R-P53 and GM-CSF in Hep3B-C and ECCG5 cells after transfection with OAV SG655-mGMP were detected by Western blot and Elisa assays, respectively. Thirdly, the enhanced growth inhibitory and augmented apoptosis inducing effects of OAV SG655-mGMP on Hep3B-C and ECCG5 cells were tested with FCM assays by comparing with the control, wild type 5 adenovirus, 11R-P53 carrying OVA in vitro. Lastly, the in vivo therapeutic effect of OAV SG655-mGMP toward ECCG5 cell-formed xenografts was studied by measuring tumor volumes post different treatments with PBS, OAV SG655-11R-P53, OAV SG655-mGM-CSF and OAV SG655-mGMP. Treatment with OAV SG655-mGMP induced significant xenograft growth inhibition, inflammation factor AIF1 expression and immune cells infiltration. Therefore, our OAV SG655-mGMP provides a novel platform to arm OVs to target cancer stem cells.

  7. Activation of the human immune system via toll-like receptors by the oncolytic parvovirus H-1.

    Science.gov (United States)

    Sieben, Maike; Schäfer, Petra; Dinsart, Christiane; Galle, Peter R; Moehler, Markus

    2013-06-01

    This study aimed to investigate the function of toll-like receptors (TLRs) during oncolytic parvovirus H-1 (H-1PV)-induced human immune responses. First, the role of TLRs in the activation of the NFκB transcription factor was characterized; second, the immunologic effects of H-1PV-induced tumor cell lysates (TCL) on human antitumor immune responses were evaluated. A human ex vivo model was used to study immune responses with dendritic cells (DCs). Human embryonic kidney cells (HEK293) transfected to stably express TLRs were used as potential human DC equivalents to further investigate the role of specific TLRs during immune activation. TLR3 and TLR9 were activated by H-1PV infection, which correlated with NFκB translocation to the nucleus and a reduced cytoplasmic IκB expression. Using a TLR-signaling reporter plasmid (pNiFty-Luc), NFκB activity was increased following H-1PV infection. In addition, human DCs coincubated with H-1PV-induced TCL demonstrated increased TLR3 and TLR9 expression. These data suggest that H-1PV-induced TCL stimulate human DCs at least in part through TLR-dependent signaling pathways. Thus, DC maturation occurred through exposure to H-1PV-induced TCL through TLR-signaling leading to NFκB-dependent activation of the adaptive immune system as indicated by the increased expression of CD86, TLR3 and TLR9. Furthermore, the transcription of various cytokines indicates the activation of immune response, therefore the production of the proinflammatory cytokine TNF-α was determined. Here, H-1PV-induced TCL significantly enhanced the TNF-α level by DCs after coculture. H-1PV oncolytic virotherapy enhances immune priming by different effects on DCs and generates antitumor immunity. These findings potentially offer a new approach to tumor therapy.

  8. Frequency Dependent Attenuation Revisited

    CERN Document Server

    Richard, Kowar; Xavier, Bonnefond

    2009-01-01

    The work is inspired by thermo-and photoacoustic imaging, where recent efforts are devoted to take into account attenuation and varying wave speed parameters. In this paper we study causal equations describing propagation of attenuated pressure waves. We review standard models like frequency power laws and and the thermo-viscous equation. The lack of causality of standard models in the parameter range relevant for photoacoustic imaging requires to derive novel equations. The main ingredients for deriving causal equations are the Kramers-Kronig relation and the mathematical concept of linear system theory. The theoretical results of this work are underpined by numerical experiments.

  9. Recombinant mumps virus as a cancer therapeutic agent

    OpenAIRE

    2016-01-01

    Mumps virus belongs to the family of Paramyxoviridae and has the potential to be an oncolytic agent. Mumps virus Urabe strain had been tested in the clinical setting as a treatment for human cancer four decades ago in Japan. These clinical studies demonstrated that mumps virus could be a promising cancer therapeutic agent that showed significant antitumor activity against various types of cancers. Since oncolytic virotherapy was not in the limelight until the beginning of the 21st century, th...

  10. Recombinant methods and materials

    Energy Technology Data Exchange (ETDEWEB)

    Roizman, B.; Post, L.E.

    1988-09-06

    This patent describes a method for stably effecting the insertion or deletion of a selected DNA sequence at a specific site in a viral genome. The method consists of: (1) isolating from the genome a linear DNA fragment comprising both (a) the specific site determined for insertion or deletion of selected DNA sequence and (b) flanking DNA sequences normally preceding and following the site; (2) preparing first and second altered genome fragments from the fragment isolated in step (1). (a) the first altered fragment comprising the fragment comprising a thymidine kinase gene in a position intermediate the ends of the fragment, and (b) the second altered fragment comprising the fragment having the selected DNA sequence inserted therein or deleted therefrom; (3) contacting the genome with the first altered fragment under conditions permitting recombination at sites of DNA sequence homology, selecting for a recombinant genome comprising the thymidine kinase gene, and isolating the recombinant genome; and (4) contacting the recombinant genome isolated in step (3) with the second altered fragment under conditions permitting recombination at sites of DNA sequence homology, selecting for a recombinant genome lacking the thymidine kinase gene, and isolating the recombinant genome product.

  11. Dissociative recombination in aeronomy

    Science.gov (United States)

    Fox, J. L.

    1989-01-01

    The importance of dissociative recombination in planetary aeronomy is summarized, and two examples are discussed. The first is the role of dissociative recombination of N2(+) in the escape of nitrogen from Mars. A previous model is updated to reflect new experimental data on the electronic states of N produced in this process. Second, the intensity of the atomic oxygen green line on the nightside of Venus is modeled. Use is made of theoretical rate coefficients for production of O (1S) in dissociative recombination from different vibrational levels of O2(+).

  12. Virotherapy of canine tumors with oncolytic vaccinia virus GLV-1h109 expressing an anti-VEGF single-chain antibody.

    Directory of Open Access Journals (Sweden)

    Sandeep S Patil

    Full Text Available Virotherapy using oncolytic vaccinia virus (VACV strains is one promising new strategy for cancer therapy. We have previously reported that oncolytic vaccinia virus strains expressing an anti-VEGF (Vascular Endothelial Growth Factor single-chain antibody (scAb GLAF-1 exhibited significant therapeutic efficacy for treatment of human tumor xenografts. Here, we describe the use of oncolytic vaccinia virus GLV-1h109 encoding GLAF-1 for canine cancer therapy. In this study we analyzed the virus-mediated delivery and production of scAb GLAF-1 and the oncolytic and immunological effects of the GLV-1h109 vaccinia virus strain against canine soft tissue sarcoma and canine prostate carcinoma in xenograft models. Cell culture data demonstrated that the GLV-1h109 virus efficiently infect, replicate in and destroy both tested canine cancer cell lines. In addition, successful expression of GLAF-1 was demonstrated in virus-infected canine cancer cells and the antibody specifically recognized canine VEGF. In two different xenograft models, the systemic administration of the GLV-1h109 virus was found to be safe and led to anti-tumor and immunological effects resulting in the significant reduction of tumor growth in comparison to untreated control mice. Furthermore, tumor-specific virus infection led to a continued production of functional scAb GLAF-1, resulting in inhibition of angiogenesis. Overall, the GLV-1h109-mediated cancer therapy and production of immunotherapeutic anti-VEGF scAb may open the way for combination therapy concept i.e. vaccinia virus mediated oncolysis and intratumoral production of therapeutic drugs in canine cancer patients.

  13. Extended disease-free interval of 6 years in a recurrent glioblastoma multiforme patient treated with G207 oncolytic viral therapy

    Directory of Open Access Journals (Sweden)

    Whisenhunt Jr TR

    2015-01-01

    Full Text Available Thomas R Whisenhunt Jr, Kiran F Rajneesh, James R Hackney, James M Markert Department of Neurosurgery, University of Alabama at Birmingham, Birmingham, AL, USA Background: Glioblastoma multiforme (GBM is a relentless primary central nervous system malignancy that remains resistant to conventional therapy despite major advances in clinical neurooncology. This report details the case of a patient who had failed conventional treatment for recurrent GBM and was ultimately treated with a genetically engineered herpes simplex virus (HSV type 1 vector, G207. Methods: Case report detailing the outcomes of one patient enrolled into the gene therapy arm of the Neurovir G207 protocol whereby stereotactic injection of 120 µL G207 viral suspension containing 1×107 plaque-forming units (or active viral particles was made into the enhancing region of the tumor. Results: In this patient, despite aggressive surgical resection, adjuvant radiotherapy and chemotherapy, tumor progression occurred. However, with G207 oncolytic therapy and brief exposures to second and third treatments, this patient had an extended survival time of 7.5 years and a 6-year apparent disease-free interval, an extraordinarily unusual finding in the pretemozolomide era. Conclusion: With minimal adjunctive chemotherapy, including one course of temozolomide, one course of procarbazine, and four cycles of irinotecan, the patient survived over 7 years before the next recurrence. Addition of G207 to this patient’s traditional therapy may have been the critical treatment producing her prolonged survival. This report demonstrates the potential for long-term response to a one-time treatment with oncolytic HSV and encourages continued research on oncolytic viral therapy for GBM. Keywords: oncolytic virotherapy, malignant glioma, tumor, herpes simplex, HSV-1, immunotherapy

  14. Genetically attenuated Trypanosoma cruzi parasites as a potential vaccination tool

    OpenAIRE

    2012-01-01

    Chagas disease is the clinical manifestation of the infection produced by the parasite Trypanosoma cruzi. Currently there is no vaccine to prevent this disease and the protection attained with vaccines containing non-replicating parasites is limited. Genetically attenuated trypanosomatid parasites can be obtained by deletion of selected genes. Gene deletion takes advantage of the fact that this parasite can undergo homologous recombination between endogenous and foreign DNA sequences artifici...

  15. Pancreatic adenocarcinoma upregulated factor (PAUF) confers resistance to pancreatic cancer cells against oncolytic parvovirus H-1 infection through IFNA receptor-mediated signaling

    Energy Technology Data Exchange (ETDEWEB)

    Kaowinn, Sirichat; Cho, Il-Rae; Moon, Jeong; Jun, Seung Won; Kim, Chang Seok [BK21+, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-736 (Korea, Republic of); Kang, Ho Young [Department of Microbiology, Pusan National University, Busan 609-736 (Korea, Republic of); Kim, Manbok [Department of Medical Science, Dankook University College of Medicine, Cheonan 330-714 (Korea, Republic of); Koh, Sang Seok [Department of Biological Sciences, Dong-A University, Busan 604-714 (Korea, Republic of); Chung, Young-Hwa, E-mail: younghc@pusan.ac.kr [BK21+, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-736 (Korea, Republic of)

    2015-04-03

    Pancreatic adenocarcinoma upregulated factor (PAUF), a novel oncogene, plays a crucial role in the development of pancreatic cancer, including its metastasis and proliferation. Therefore, PAUF-expressing pancreatic cancer cells could be important targets for oncolytic virus-mediated treatment. Panc-1 cells expressing PAUF (Panc-PAUF) showed relative resistance to parvovirus H-1 infection compared with Panc-1 cells expressing an empty vector (Panc-Vec). Of interest, expression of type I IFN-α receptor (IFNAR) was higher in Panc-PAUF cells than in Panc-Vec cells. Increased expression of IFNAR in turn increased the activation of Stat1 and Tyk2 in Panc-PAUF cells compared with that in Panc-Vec cells. Suppression of Tyk2 and Stat1, which are important downstream molecules for IFN-α signaling, sensitized pancreatic cancer cells to parvovirus H-1-mediated apoptosis. Further, constitutive suppression of PAUF sensitized Bxpc3 pancreatic cancer cells to parvovirus H-1 infection. Taken together, these results suggested that PAUF conferred resistance to pancreatic cancer cells against oncolytic parvovirus H-1 infection through IFNAR-mediated signaling. - Highlights: • PAUF confers resistance against oncolytic parvovirus H-1 infection. • PAUF enhances the expression of IFNAR in Panc-1 cells. • Increased activation of Tyk2 or Stat1 by PAUF provides resistance to parvovirus H-1-mediated apoptosis. • Constitutive inhibition of PAUF enhances parvovirus H-1-mediated oncolysis of Bxpc3 pancreatic cancer cells.

  16. Identification and manipulation of the molecular determinants influencing poliovirus recombination.

    Directory of Open Access Journals (Sweden)

    Charles Runckel

    2013-02-01

    Full Text Available The control and prevention of communicable disease is directly impacted by the genetic mutability of the underlying etiological agents. In the case of RNA viruses, genetic recombination may impact public health by facilitating the generation of new viral strains with altered phenotypes and by compromising the genetic stability of live attenuated vaccines. The landscape of homologous recombination within a given RNA viral genome is thought to be influenced by several factors; however, a complete understanding of the genetic determinants of recombination is lacking. Here, we utilize gene synthesis and deep sequencing to create a detailed recombination map of the poliovirus 1 coding region. We identified over 50 thousand breakpoints throughout the genome, and we show the majority of breakpoints to be concentrated in a small number of specific "hotspots," including those associated with known or predicted RNA secondary structures. Nucleotide base composition was also found to be associated with recombination frequency, suggesting that recombination is modulated across the genome by predictable and alterable motifs. We tested the predictive utility of the nucleotide base composition association by generating an artificial hotspot in the poliovirus genome. Our results imply that modification of these motifs could be extended to whole genome re-designs for the development of recombination-deficient, genetically stable live vaccine strains.

  17. Oncolytic targeting of androgen-sensitive prostate tumor by the respiratory syncytial virus (RSV: consequences of deficient interferon-dependent antiviral defense

    Directory of Open Access Journals (Sweden)

    Hubbard Gene B

    2011-01-01

    Full Text Available Abstract Background Oncolytic virotherapy for cancer treatment utilizes viruses for selective infection and death of cancer cells without any adverse effect on normal cells. We previously reported that the human respiratory syncytial virus (RSV is a novel oncolytic virus against androgen-independent PC-3 human prostate cancer cells. The present study extends the result to androgen-dependent prostate cancer, and explores the underlying mechanism that triggers RSV-induced oncolysis of prostate cancer cells. Methods The oncolytic effect of RSV on androgen-sensitive LNCaP human prostate cancer cells and on androgen-independent RM1 murine prostate cancer cells was studied in vitro in culture and in vivo in a xenograft or allograft tumor model. In vitro, cell viability, infectivity and apoptosis were monitored by MTT assay, viral plaque assay and annexin V staining, respectively. In vivo studies involved virus administration to prostate tumors grown in immune compromised nude mice and in syngeneic immune competent C57BL/6J mice. Anti-tumorogenic oncolytic activity was monitored by measuring tumor volume, imaging bioluminescent tumors in live animals and performing histopathological analysis and TUNEL assay with tumors Results We show that RSV imposes a potent oncolytic effect on LNCaP prostate cancer cells. RSV infectivity was markedly higher in LNCaP cells compared to the non-tumorigenic RWPE-1 human prostate cells. The enhanced viral burden led to LNCaP cell apoptosis and growth inhibition of LNCaP xenograft tumors in nude mice. A functional host immune response did not interfere with RSV-induced oncolysis, since growth of xenograft tumors in syngeneic C57BL/6J mice from murine RM1 cells was inhibited upon RSV administration. LNCaP cells failed to activate the type-I interferon (IFNα/β-induced transcription factor STAT-1, which is required for antiviral gene expression, although these cells could produce IFN in response to RSV infection. The

  18. Regulation of Meiotic Recombination

    Energy Technology Data Exchange (ETDEWEB)

    Gregory p. Copenhaver

    2011-11-09

    Meiotic recombination results in the heritable rearrangement of DNA, primarily through reciprocal exchange between homologous chromosome or gene conversion. In plants these events are critical for ensuring proper chromosome segregation, facilitating DNA repair and providing a basis for genetic diversity. Understanding this fundamental biological mechanism will directly facilitate trait mapping, conventional plant breeding, and development of genetic engineering techniques that will help support the responsible production and conversion of renewable resources for fuels, chemicals, and the conservation of energy (1-3). Substantial progress has been made in understanding the basal recombination machinery, much of which is conserved in organisms as diverse as yeast, plants and mammals (4, 5). Significantly less is known about the factors that regulate how often and where that basal machinery acts on higher eukaryotic chromosomes. One important mechanism for regulating the frequency and distribution of meiotic recombination is crossover interference - or the ability of one recombination event to influence nearby events. The MUS81 gene is thought to play an important role in regulating the influence of interference on crossing over. The immediate goals of this project are to use reverse genetics to identify mutants in two putative MUS81 homologs in the model plant Arabidopsis thaliana, characterize those mutants and initiate a novel forward genetic screen for additional regulators of meiotic recombination. The long-term goal of the project is to understand how meiotic recombination is regulated in higher eukaryotes with an emphasis on the molecular basis of crossover interference. The ability to monitor recombination in all four meiotic products (tetrad analysis) has been a powerful tool in the arsenal of yeast geneticists. Previously, the qrt mutant of Arabidopsis, which causes the four pollen products of male meiosis to remain attached, was developed as a facile system

  19. Construction and identification of dual-regulated oncolytic adenovirus with dual-efficacy%双调控双功效溶瘤腺病毒的构建及意义

    Institute of Scientific and Technical Information of China (English)

    孙立臣; 潘旭波; 周先亭; 宋占文; 苏长青

    2013-01-01

    目的 构建表达Survivin基因小发卡RNA和内皮抑素基因的双调控双功效肿瘤特异性溶瘤腺病毒(CNHK500-shSRV-mE,以下简称双调控腺病毒),为肝癌的基因治疗奠定基础.方法 以人端粒酶逆转录酶启动子(hTERT)调控腺病毒E1a基因,缺氧调控元件序列(HRE)调控E1b基因,重组双调控双功效的肿瘤特异性溶瘤腺病毒载体;于E1区插入Survivin基因序列设计特异shRNA和全长内皮抑素基因构建双调控腺病毒.将双调控腺病毒分别感染人肝癌细胞株SMMC-7721、BEL-7402,观察病毒的增殖活性.结果 双调控腺病毒能在肝癌细胞中特异性高拷贝增殖,而在正常细胞系中几乎不增殖.结论 双调控腺病毒成功构建;其为肝癌的基因治疗奠定了基础.%Objective To construct the dual-regulated oncolytic adenovirus carrying surviving-shRNA and endostatin in order to investigate its replicative activity in hepatocellular carcinoma. Methods The hTERT promoter was cloned and used to control El a expression. HRE was cloned and used to control Elb expression. The survivin shRNA and mouse endostatin gene were inserted into adenoviral genome. The recombinant adenovirus was used to infect hepatocellular carcinoma cell lines and its replicative activity was observed. Result The recombinant adenovirus CNHK500-shSRV-mE was replicated selectively in cancer cells but not normal cells. Conclusion CNHK500-shSRV-mE can replicate selectively in cancer cells, which can be used in cancer gene therapy.

  20. Ultrasonic attenuation in pearlitic steel.

    Science.gov (United States)

    Du, Hualong; Turner, Joseph A

    2014-03-01

    Expressions for the attenuation coefficients of longitudinal and transverse ultrasonic waves are developed for steel with pearlitic microstructure. This type of lamellar duplex microstructure influences attenuation because of the lamellar spacing. In addition, longitudinal attenuation measurements were conducted using an unfocused transducer with 10 MHz central frequency on the cross section of a quenched railroad wheel sample. The dependence of longitudinal attenuation on the pearlite microstructure is observed from the changes of longitudinal attenuation from the quenched tread surface to deeper locations. The results show that the attenuation value is lowest and relatively constant within the quench depth, then increases linearly. The experimental results demonstrate a reasonable agreement with results from the theoretical model. Ultrasonic attenuation provides an important non-destructive method to evaluate duplex microstructure within grains which can be implemented for quality control in conjunction with other manufacturing processes.

  1. Recombination experiments at CRYRING

    Energy Technology Data Exchange (ETDEWEB)

    Spies, W.; Glans, P.; Zong, W.; Gao, H.; Andler, G.; Justiniano, E.; Saito, M.; Schuch, R

    1998-11-15

    Recent advances in studies of electron-ion recombination processes at low relative energies with the electron cooler of the heavy-ion storage ring CRYRING are shown. Through the use of an adiabatically expanded electron beam, collisions down to 10{sup -4}eV relative energies were measured with highly charged ions stored in the ring at around 15 MeV/amu energies. Examples of recombination measurements for bare ions of D{sup +}, He{sup 2+}, N{sup 7+}, Ne{sup 10+} and Si{sup 14+} are presented. Further on, results of an experiment measuring laser-induced recombination (LIR) into n=3 states of deuterium with polarized laser light are shown.

  2. Recombinant Helicobacter pylori catalase

    Institute of Scientific and Technical Information of China (English)

    Yang Bai; Ya-Li Zhang; Jian-Feng Jin; Ji-De Wang; Zhao-Shan Zhang

    2003-01-01

    AIM: To construct a recombinant strain which highly expresses catalase of Helicobacter pylori(H.pylori) and assay the activity of H. pylori catalase.METHODS: The catalase DNA was amplified from H. pylori chromosomal DNA with PCR techniques and inserted into the prokaryotie expression vector pET-22b (+), and then was transformed into the BL21 (DE3) E. coli strain which expressed catalase recombinant protein. The activity of H.pylori catalase was assayed by the Beers & Sizers.RESULTS: DNA sequence analysis showed that the sequence of catalase DNA was the same as GenBank's research. The catalase recombinant protein amounted to 24.4 % of the total bacterial protein after induced with IPTG for 3 hours at 37 ℃ and the activity of H. pylori catalase was high in the BL21 (DE3) E. coli strain.CONCLUSION: A clone expressing high activity H. pylori catalase is obtained, laying a good foundation for further studies.

  3. Imaging characteristics, tissue distribution, and spread of a novel oncolytic vaccinia virus carrying the human sodium iodide symporter.

    Directory of Open Access Journals (Sweden)

    Dana Haddad

    Full Text Available INTRODUCTION: Oncolytic viruses show promise for treating cancer. However, to assess therapy and potential toxicity, a noninvasive imaging modality is needed. This study aims to determine the in vivo biodistribution, and imaging and timing characteristics of a vaccinia virus, GLV-1h153, encoding the human sodium iodide symporter (hNIS. METHODS: GLV-1h153 was modified from GLV-1h68 to encode the hNIS gene. Timing of cellular uptake of radioiodide (131I in human pancreatic carcinoma cells PANC-1 was assessed using radiouptake assays. Viral biodistribution was determined in nude mice bearing PANC-1 xenografts, and infection in tumors confirmed histologically and optically via Green Fluorescent Protein (GFP and bioluminescence. Timing characteristics of enhanced radiouptake in xenografts were assessed via (124I-positron emission tomography (PET. Detection of systemic administration of virus was investigated with both (124I-PET and 99m-technecium gamma-scintigraphy. RESULTS: GLV-1h153 successfully facilitated time-dependent intracellular uptake of (131I in PANC-1 cells with a maximum uptake at 24 hours postinfection (P<0.05. In vivo, biodistribution profiles revealed persistence of virus in tumors 5 weeks postinjection at 10(9 plaque-forming unit (PFU/gm tissue, with the virus mainly cleared from all other major organs. Tumor infection by GLV-1h153 was confirmed via optical imaging and histology. GLV-1h153 facilitated imaging virus replication in tumors via PET even at 8 hours post radiotracer injection, with a mean %ID/gm of 3.82 ± 0.46 (P<0.05 2 days after intratumoral administration of virus, confirmed via tissue radiouptake assays. One week post systemic administration, GLV-1h153-infected tumors were detected via (124I-PET and 99m-technecium-scintigraphy. CONCLUSION: GLV-1h153 is a promising oncolytic agent against pancreatic cancer with a promising biosafety profile. GLV-1h153 facilitated time-dependent hNIS-specific radiouptake in pancreatic

  4. Sickle Cells Abolish Melanoma Tumorigenesis in Hemoglobin SS Knockin Mice and Augment the Tumoricidal Effect of Oncolytic Virus In Vivo.

    Science.gov (United States)

    Sun, Chiang Wang; Willmon, Candice; Wu, Li-Chen; Knopick, Peter; Thoerner, Jutta; Vile, Richard; Townes, Tim M; Terman, David S

    2016-01-01

    Insights from the study of cancer resistance in animals have led to the discovery of novel anticancer pathways and opened new venues for cancer prevention and treatment. Sickle cells (SSRBCs) from subjects with homozygous sickle cell anemia (SCA) have been shown to target hypoxic tumor niches, induce diffuse vaso-occlusion, and potentiate a tumoricidal response in a heme- and oxidant-dependent manner. These findings spawned the hypothesis that SSRBCs and the vasculopathic microenvironment of subjects with SCA might be inimical to tumor outgrowth and thereby constitute a natural antitumor defense. We therefore implanted the B16F10 melanoma into humanized hemoglobin SS knockin mice which exhibit the hematologic and vasculopathic sequelae of human SCA. Over the 31-day observation period, hemoglobin SS mice showed no significant melanoma outgrowth. By contrast, 68-100% of melanomas implanted in background and hemoglobin AA knockin control mice reached the tumor growth end point (p SS knockin mice also exhibited established markers of underlying vasculopathy, e.g., chronic hemolysis (anemia, reticulocytosis) and vascular inflammation (leukocytosis) that differed significantly from all control groups. Genetic differences or normal AA gene knockin do not explain the impaired tumor outgrowth in SS knockin mice. These data point instead to the chronic pro-oxidative vasculopathic network in these mice as the predominant cause. In related studies, we demonstrate the ability of the sickle cell component of this system to function as a therapeutic vehicle in potentiating the oncolytic/vasculopathic effect of RNA reovirus. Sickle cells were shown to efficiently adsorb and transfer the virus to melanoma cells where it induced apoptosis even in the presence of anti-reovirus neutralizing antibodies. In vivo, SSRBCs along with their viral cargo rapidly targeted the tumor and initiated a tumoricidal response exceeding that of free virus and similarly loaded normal RBCs without

  5. Recombinant Parvoviruses Armed to Deliver CXCL4L1 and CXCL10 Are Impaired in Their Antiangiogenic and Antitumoral Effects in a Kaposi Sarcoma Tumor Model Due To the Chemokines' Interference with the Virus Cycle.

    Science.gov (United States)

    Dinsart, Christiane; Pervolaraki, Kalliopi; Stroh-Dege, Alexandra; Lavie, Muriel; Ronsse, Isabelle; Rommelaere, Jean; Van Damme, Jo; Van Raemdonck, Katrien; Struyf, Sofie

    2017-03-01

    Application of oncolytic viruses is a valuable option to broaden the armament of anticancer therapies, as these combine specific cytotoxic effects and immune-stimulating properties. The self-replicating H-1 parvovirus (H-1PV) is a prototypical oncolytic virus that, besides targeting tumor cells, also infects endothelial cells, thus combining oncolytic and angiostatic traits. To increase its therapeutic value, H-1PV can be armed with cytokines or chemokines to enhance the immunological response. Some chemokines-more specifically, the CXCR3 ligands CXCL4L1 and CXCL10-combine immune-stimulating properties with angiostatic activity. This study explores the therapeutic value of recombinant parvoviruses carrying CXCL4L1 or CXCL10 transgenes (Chi-H1/CXCL4L1 or Chi-H1/CXCL10, respectively) to inhibit the growth of the human Kaposi sarcoma cell line KS-IMM. KS-IMM cells infected by Chi-H1/CXCL4L1 or Chi-H1/CXCL10 released the corresponding chemokine and showed reduced migratory capacity. Therefore, the antitumoral capacity of Chi-H1/CXCL4L1 or Chi-H1/CXCL10 was tested in mice. Either in vitro infected KS-IMM cells were injected or subcutaneously growing KS-IMM xenografts were treated by peritumoral injections of the different viruses. Surprisingly, the transgenes did not increase the antitumoral effect of natural H-1PV. Further experiments indicated that CXCL4L1 and CXCL10 interfered with the expression of the viral NS1 protein in KS-IMM cells. These results indicate that the outcome of parvovirus-based delivery of CXCR3 ligands might be tumor cell type dependent, and hence its application must be considered carefully.

  6. Recombinant measles AIK-C vaccine strain expressing heterologous virus antigens.

    Science.gov (United States)

    Nakayama, Tetsuo; Sawada, Akihito; Yamaji, Yoshiaki; Ito, Takashi

    2016-01-04

    Further attenuated measles vaccines were developed more than 50 years ago and have been used throughout the world. Recombinant measles vaccine candidates have been developed and express several heterologous virus protective antigens. Immunogenicity and protective actions were confirmed using experimental animals: transgenic mice, cotton rats, and primates. The recent development of measles vaccine-based vectored vaccine candidates has been reviewed and some information on recombinant measles vaccines expressing respiratory syncytial virus proteins has been shown and discussed.

  7. Recombineering linear BACs.

    Science.gov (United States)

    Chen, Qingwen; Narayanan, Kumaran

    2015-01-01

    Recombineering is a powerful genetic engineering technique based on homologous recombination that can be used to accurately modify DNA independent of its sequence or size. One novel application of recombineering is the assembly of linear BACs in E. coli that can replicate autonomously as linear plasmids. A circular BAC is inserted with a short telomeric sequence from phage N15, which is subsequently cut and rejoined by the phage protelomerase enzyme to generate a linear BAC with terminal hairpin telomeres. Telomere-capped linear BACs are protected against exonuclease attack both in vitro and in vivo in E. coli cells and can replicate stably. Here we describe step-by-step protocols to linearize any BAC clone by recombineering, including inserting and screening for presence of the N15 telomeric sequence, linearizing BACs in vivo in E. coli, extracting linear BACs, and verifying the presence of hairpin telomere structures. Linear BACs may be useful for functional expression of genomic loci in cells, maintenance of linear viral genomes in their natural conformation, and for constructing innovative artificial chromosome structures for applications in mammalian and plant cells.

  8. Recombinant renewable polyclonal antibodies.

    Science.gov (United States)

    Ferrara, Fortunato; D'Angelo, Sara; Gaiotto, Tiziano; Naranjo, Leslie; Tian, Hongzhao; Gräslund, Susanne; Dobrovetsky, Elena; Hraber, Peter; Lund-Johansen, Fridtjof; Saragozza, Silvia; Sblattero, Daniele; Kiss, Csaba; Bradbury, Andrew R M

    2015-01-01

    Only a small fraction of the antibodies in a traditional polyclonal antibody mixture recognize the target of interest, frequently resulting in undesirable polyreactivity. Here, we show that high-quality recombinant polyclonals, in which hundreds of different antibodies are all directed toward a target of interest, can be easily generated in vitro by combining phage and yeast display. We show that, unlike traditional polyclonals, which are limited resources, recombinant polyclonal antibodies can be amplified over one hundred million-fold without losing representation or functionality. Our protocol was tested on 9 different targets to demonstrate how the strategy allows the selective amplification of antibodies directed toward desirable target specific epitopes, such as those found in one protein but not a closely related one, and the elimination of antibodies recognizing common epitopes, without significant loss of diversity. These recombinant renewable polyclonal antibodies are usable in different assays, and can be generated in high throughput. This approach could potentially be used to develop highly specific recombinant renewable antibodies against all human gene products.

  9. Recombinant DNA for Teachers.

    Science.gov (United States)

    Duvall, James G., III

    1992-01-01

    A science teacher describes his experience at a workshop to learn to teach the Cold Spring Harbor DNA Science Laboratory Protocols. These protocols lead students through processes for taking E. coli cells and transforming them into a new antibiotic resistant strain. The workshop featured discussions of the role of DNA recombinant technology in…

  10. Salmonella enterica serovar typhimurium strains with regulated delayed attenuation in vivo.

    Science.gov (United States)

    Curtiss, Roy; Wanda, Soo-Young; Gunn, Bronwyn M; Zhang, Xin; Tinge, Steven A; Ananthnarayan, Vidya; Mo, Hua; Wang, Shifeng; Kong, Wei

    2009-03-01

    Recombinant bacterial vaccines must be fully attenuated for animal or human hosts to avoid inducing disease symptoms while exhibiting a high degree of immunogenicity. Unfortunately, many well-studied means for attenuating Salmonella render strains more susceptible to host defense stresses encountered following oral vaccination than wild-type virulent strains and/or impair their ability to effectively colonize the gut-associated and internal lymphoid tissues. This thus impairs the ability of recombinant vaccines to serve as factories to produce recombinant antigens to induce the desired protective immunity. To address these problems, we designed strains that display features of wild-type virulent strains of Salmonella at the time of immunization to enable strains first to effectively colonize lymphoid tissues and then to exhibit a regulated delayed attenuation in vivo to preclude inducing disease symptoms. We recently described one means to achieve this based on a reversible smooth-rough synthesis of lipopolysaccharide O antigen. We report here a second means to achieve regulated delayed attenuation in vivo that is based on the substitution of a tightly regulated araC P(BAD) cassette for the promoters of the fur, crp, phoPQ, and rpoS genes such that expression of these genes is dependent on arabinose provided during growth. Thus, following colonization of lymphoid tissues, the Fur, Crp, PhoPQ, and/or RpoS proteins cease to be synthesized due to the absence of arabinose such that attenuation is gradually manifest in vivo to preclude induction of diseases symptoms. Means for achieving regulated delayed attenuation can be combined with other mutations, which together may yield safe efficacious recombinant attenuated Salmonella vaccines.

  11. Synergistic combination of valproic acid and oncolytic parvovirus H-1PV as a potential therapy against cervical and pancreatic carcinomas.

    Science.gov (United States)

    Li, Junwei; Bonifati, Serena; Hristov, Georgi; Marttila, Tiina; Valmary-Degano, Séverine; Stanzel, Sven; Schnölzer, Martina; Mougin, Christiane; Aprahamian, Marc; Grekova, Svitlana P; Raykov, Zahari; Rommelaere, Jean; Marchini, Antonio

    2013-10-01

    The rat parvovirus H-1PV has oncolytic and tumour-suppressive properties potentially exploitable in cancer therapy. This possibility is being explored and results are encouraging, but it is necessary to improve the oncotoxicity of the virus. Here we show that this can be achieved by co-treating cancer cells with H-1PV and histone deacetylase inhibitors (HDACIs) such as valproic acid (VPA). We demonstrate that these agents act synergistically to kill a range of human cervical carcinoma and pancreatic carcinoma cell lines by inducing oxidative stress, DNA damage and apoptosis. Strikingly, in rat and mouse xenograft models, H-1PV/VPA co-treatment strongly inhibits tumour growth promoting complete tumour remission in all co-treated animals. At the molecular level, we found acetylation of the parvovirus nonstructural protein NS1 at residues K85 and K257 to modulate NS1-mediated transcription and cytotoxicity, both of which are enhanced by VPA treatment. These results warrant clinical evaluation of H-1PV/VPA co-treatment against cervical and pancreatic ductal carcinomas.

  12. Ultrasound-induced cavitation enhances the delivery and therapeutic efficacy of an oncolytic virus in an in vitro model.

    Science.gov (United States)

    Bazan-Peregrino, Miriam; Arvanitis, Costas D; Rifai, Bassel; Seymour, Leonard W; Coussios, Constantin-C

    2012-01-30

    We investigated whether ultrasound-induced cavitation at 0.5 MHz could improve the extravasation and distribution of a potent breast cancer-selective oncolytic adenovirus, AdEHE2F-Luc, to tumour regions that are remote from blood vessels. We developed a novel tumour-mimicking model consisting of a gel matrix containing human breast cancer cells traversed by a fluid channel simulating a tumour blood vessel, through which the virus and microbubbles could be made to flow. Ultrasonic pressures were chosen to maximize either broadband emissions, associated with inertial cavitation, or ultraharmonic emissions, associated with stable cavitation, while varying duty cycle to keep the total acoustic energy delivered constant for comparison across exposures. None of the exposure conditions tested affected cell viability in the absence of the adenovirus. When AdEHE2F-Luc was delivered via the vessel, inertial cavitation increased transgene expression in tumour cells by up to 200 times. This increase was not observed in the absence of Coxsackie and Adenovirus Receptor cell expression, discounting sonoporation as the mechanism of action. In the presence of inertial cavitation, AdEHE2F-Luc distribution was greatly improved in the matrix surrounding the vessel, particularly in the direction of the ultrasound beam; this enabled AdEHE2F-Luc to kill up to 80% of cancer cells within the ultrasound focal volume in the gel 24 hours after delivery, compared to 0% in the absence of cavitation.

  13. Prevention of EBV lymphoma development by oncolytic myxoma virus in a murine xenograft model of post-transplant lymphoproliferative disease.

    Science.gov (United States)

    Kim, Manbok; Rahman, Masmudur M; Cogle, Christopher R; McFadden, Grant

    2015-07-10

    Epstein-Barr virus (EBV) has been associated with a variety of epithelial and hematologic malignancies, including B-, T- and NK cell-lymphomas, Hodgkin's disease (HD), post-transplant lymphoproliferative diseases (LPDs), nasopharyngeal and gastric carcinomas, smooth muscle tumors, and HIV-associated lymphomas. Currently, treatment options for EBV-associated malignancies are limited. We have previously shown that myxoma virus specifically targets various human solid tumors and leukemia cells in a variety of animal models, while sparing normal human or murine tissues. Since transplant recipients of bone marrow or solid organs often develop EBV-associated post-transplant LPDs and lymphoma, myxoma virus may be of utility to prevent EBV-associated malignancies in immunocompromised transplant patients where treatment options are frequently limited. In this report, we demonstrate the safety and efficacy of myxoma virus purging as a prophylactic strategy for preventing post-transplant EBV-transformed human lymphomas, using a highly immunosuppressed mouse xenotransplantation model. This provides support for developing myxoma virus as a potential oncolytic therapy for preventing EBV-associated LPDs following transplantation of bone marrow or solid organ allografts.

  14. Oncolytic adenovirus and doxorubicin-based chemotherapy results in synergistic antitumor activity against soft-tissue sarcoma.

    Science.gov (United States)

    Siurala, Mikko; Bramante, Simona; Vassilev, Lotta; Hirvinen, Mari; Parviainen, Suvi; Tähtinen, Siri; Guse, Kilian; Cerullo, Vincenzo; Kanerva, Anna; Kipar, Anja; Vähä-Koskela, Markus; Hemminki, Akseli

    2015-02-15

    Despite originating from several different tissues, soft-tissue sarcomas (STS) are often grouped together as they share mesenchymal origin and treatment guidelines. Also, with some exceptions, a common denominator is that when the tumor cannot be cured with surgery, the efficacy of current therapies is poor and new treatment modalities are thus needed. We have studied the combination of a capsid-modified oncolytic adenovirus CGTG-102 (Ad5/3-D24-GMCSF) with doxorubicin, with or without ifosfamide, the preferred first-line chemotherapeutic options for most types of STS. We show that CGTG-102 and doxorubicin plus ifosfamide together are able to increase cell killing of Syrian hamster STS cells over single agents, as well as upregulate immunogenic cell death markers. When tested in vivo against established STS tumors in fully immunocompetent Syrian hamsters, the combination was highly effective. CGTG-102 and doxorubicin (without ifosfamide) resulted in synergistic antitumor efficacy against human STS xenografts in comparison with single agent treatments. Doxorubicin increased adenoviral replication in human and hamster STS cells, potentially contributing to the observed therapeutic synergy. In conclusion, the preclinical data generated here support clinical translation of the combination of CGTG-102 and doxorubicin, or doxorubicin plus ifosfamide, for the treatment of STS, and provide clues on the mechanisms of synergy.

  15. Safety and biodistribution of a double-deleted oncolytic vaccinia virus encoding CD40 ligand in laboratory Beagles.

    Science.gov (United States)

    Autio, Karoliina; Knuuttila, Anna; Kipar, Anja; Pesonen, Sari; Guse, Kilian; Parviainen, Suvi; Rajamäki, Minna; Laitinen-Vapaavuori, Outi; Vähä-Koskela, Markus; Kanerva, Anna; Hemminki, Akseli

    2014-01-01

    We evaluated adverse events, biodistribution and shedding of oncolytic vaccinia virus encoding CD40 ligand in two Beagles, in preparation for a phase 1 trial in canine cancer patients. Dog 1 received one dose of vaccinia virus and was euthanized 24 hours afterwards, while dog 2 received virus four times once weekly and was euthanized 7 days after that. Dogs were monitored for adverse events and underwent a detailed postmortem examination. Blood, saliva, urine, feces, and organs were collected for virus detection. Dog 1 had mild fever and lethargy while dog 2 experienced a possible seizure 5.5 hours after first virus administration. Viral DNA declined quickly in the blood after virus administration in both dogs but was still detectable 1 week later by quantitative polymerase chain reaction. Only samples taken directly after virus infusion contained infectious virus. Small amounts of viral DNA, but no infectious virus, were detected in a few saliva and urine samples. Necropsies did not reveal any relevant pathological changes and virus DNA was detected mainly in the spleen. The dogs in the study did not have cancer, and thus adverse events could be more common and viral load higher in dogs with tumors which allow viral amplification.

  16. Selective purging of human multiple myeloma cells from autologous stem cell transplant grafts using oncolytic myxoma virus

    Science.gov (United States)

    Bartee, Eric; Chan, Winnie S.; Moreb, Jan S.; Cogle, Christopher R.; McFadden, Grant

    2012-01-01

    Autologous stem cell transplantation (ASCT) and novel therapies have improved overall survival of patients with multiple myeloma; however, most patients relapse and eventually succumb to their disease. Evidence indicates that residual cancer cells contaminate autologous grafts and may contribute to early relapses after ASCT. Here, we demonstrate that ex vivo treatment with an oncolytic poxvirus called myxoma virus results in specific elimination of human myeloma cells by inducing rapid cellular apoptosis while fully sparing normal hematopoietic stem and progenitor cells (HSPCs). The specificity of this elimination is based on strong binding of the virus to myeloma cells coupled with an inability of the virus to bind or infect CD34+ HSPCs. These two features allow myxoma to readily identify and distinguish even low levels of myeloma cells in complex mixtures. This ex vivo MYXV treatment also effectively inhibits systemic in vivo engraftment of human myeloma cells into immunodeficient mice and results in efficient elimination of primary CD138+ myeloma cells contaminating patient hematopoietic cell products. We conclude that ex vivo myxoma treatment represents a safe and effective method to selectively eliminate myeloma cells from hematopoietic autografts prior to reinfusion. PMID:22516053

  17. Syngeneic syrian hamster tumors feature tumor-infiltrating lymphocytes allowing adoptive cell therapy enhanced by oncolytic adenovirus in a replication permissive setting.

    Science.gov (United States)

    Siurala, Mikko; Vähä-Koskela, Markus; Havunen, Riikka; Tähtinen, Siri; Bramante, Simona; Parviainen, Suvi; Mathis, J Michael; Kanerva, Anna; Hemminki, Akseli

    2016-05-01

    Adoptive transfer of tumor-infiltrating lymphocytes (TIL) has shown promising yet sometimes suboptimal results in clinical trials for advanced cancer, underscoring the need for approaches improving efficacy and safety. Six implantable syngeneic tumor cell lines of the Syrian hamster were used to initiate TIL cultures. TIL generated from tumor fragments cultured in human interleukin-2 (IL-2) for 10 d were adoptively transferred into tumor-bearing hamsters with concomitant intratumoral injections of oncolytic adenovirus (Ad5-D24) for the assessment of antitumor efficacy. Pancreatic cancer (HapT1) and melanoma (RPMI 1846) TIL exhibited potent and tumor-specific cytotoxicity in effector-to-target (E/T) assays. MHC Class I blocking abrogated the cell killing of RPMI 1846 TIL, indicating cytotoxic CD8(+) T-cell activity. When TIL were combined with Ad5-D24 in vitro, HapT1 tumor cell killing was significantly enhanced over single agents. In vivo, the intratumoral administration of HapT1 TIL and Ad5-D24 resulted in improved tumor growth control compared with either treatment alone. Additionally, splenocytes derived from animals treated with the combination of Ad5-D24 and TIL killed autologous tumor cells more efficiently than monotherapy-derived splenocytes, suggesting that systemic antitumor immunity was induced. For the first time, TIL of the Syrian hamster have been cultured, characterized and used therapeutically together with oncolytic adenovirus for enhancing the efficacy of TIL therapy. Our results support human translation of oncolytic adenovirus as an enabling technology for adoptive T-cell therapy of solid tumors.

  18. Cancer targeting Gene-Viro-Therapy specific for liver cancer by α-fetoprotein-controlled oncolytic adenovirus expression of SOCS3 and IL-24

    Institute of Scientific and Technical Information of China (English)

    Xin Cao; Ruicheng Wei; Xinran Liu; Yan Zeng; Hongling Huang; Miao Ding; Kangjian Zhang; Xin-Yuan Liu

    2011-01-01

    The combination of gene therapy and virotherapy for cancer treatment has received close attention and has become a trend in the field of cancer biotherapy.A strategy called 'Cancer Targeting Gene-Viro-Therapy' (CTGVT) or 'Gene Armed Oncolytic Viral Therapy'(GAOVT) has been proposed,in which an antitumor gene is inserted into an oncolytic viral vector.In our previous study,a dual-regulated oncolytic adenovirus with enhanced safety for normal cells and strict liver cancertargeting ability,designated Ad·enAFP· E1A· E1 B (A55)(briefly Ad·enAFP·D55),was successfully constructed. In the current work,interleukin-24 (IL-24) and suppressor of cytokine signaling 3 (SOCS3) genes were packaged into Ad·enAFP·D55.The new constructs,Ad·enAFP·D55-(IL-24) and Ad·enAFP·D55-(SOCS3),showed improved tumoricidal activity in hepatoma cell lines compared with the oncolytic viral vector Ad·enAFP·D55.The coadministrationofAd · enAFP· D55-(IL-24)and Ad·enAFP·D55-(SOCS3) showed much better antitumor effect than Ad·enAFP·D55-(IL-24) or Ad·enAFP·D55-(SOCS3) alone both in vitro and in a nude mouse xenograft model.Moreover,our results also showed that blockade of the Jak/Stat3 pathway by Ad·enAFP·D55-(SOCS3) infection in HuH-7 cells could down-regulate some anti-apoptosis proteins,such as XIAP,Bcl-xL,and survivin,whichmightsensitizethecellsto Ad·enAFP·D55-(IL-24)-induced apoptosis.These results indicate that co-administration of Ad·enAFP·D55-(IL-24) and Ad·enAFP·D55-(SOCS3) may serve as a candidate therapeutic approach for the treatment of liver cancer.

  19. Toxicology and Biodistribution Studies for MGH2.1, an Oncolytic Virus that Expresses Two Prodrug-activating Genes, in Combination with Prodrugs

    OpenAIRE

    Kasai, Kazue; Nakashima, Hiroshi; Liu, Fang; Kerr, Samantha; Wang, Jiang, 1959-; Phelps, Mitch; Potter, Philip M.; Goins, William B; Fernandez, Soledad A.; Chiocca, E. Antonio

    2013-01-01

    MGH2.1 is a herpes simplex virus type 1 (HSV1) oncolytic virus that expresses two prodrug-activating transgenes: the cyclophosphamide (CPA)-activating cytochrome P4502B1 (CYP2B1) and the CPT11-activating secreted human intestinal carboxylesterase (shiCE). Toxicology and biodistribution of MGH2.1 in the presence/absence of prodrugs was evaluated in mice. MGH2.1 ± prodrugs was cytotoxic to human glioma cells, but not to normal cells. Pharmacokinetically, intracranial MGH2.1 did not significantl...

  20. SUMO Wrestles with Recombination

    Directory of Open Access Journals (Sweden)

    Lumír Krejčí

    2012-07-01

    Full Text Available DNA double-strand breaks (DSBs comprise one of the most toxic DNA lesions, as the failure to repair a single DSB has detrimental consequences on the cell. Homologous recombination (HR constitutes an error-free repair pathway for the repair of DSBs. On the other hand, when uncontrolled, HR can lead to genome rearrangements and needs to be tightly regulated. In recent years, several proteins involved in different steps of HR have been shown to undergo modification by small ubiquitin-like modifier (SUMO peptide and it has been suggested that deficient sumoylation impairs the progression of HR. This review addresses specific effects of sumoylation on the properties of various HR proteins and describes its importance for the homeostasis of DNA repetitive sequences. The article further illustrates the role of sumoylation in meiotic recombination and the interplay between SUMO and other post-translational modifications.

  1. Recombinant Human Enterovirus 71

    OpenAIRE

    2004-01-01

    Two human enterovirus 71 (HEV71) isolates were identified from hand, foot and mouth disease patients with genome sequences that had high similarity to HEV71 (>93%) at 5´ UTR, P1, and P2 and coxsackievirus A16 (CV-A16, >85%) at P3 and 3´UTR. Intertypic recombination is likely to have occurred between HEV71 and CV-A16 or an as-yet to be described CV-A16-like virus.

  2. Vaxvec: The first web-based recombinant vaccine vector database and its data analysis.

    Science.gov (United States)

    Deng, Shunzhou; Martin, Carly; Patil, Rasika; Zhu, Felix; Zhao, Bin; Xiang, Zuoshuang; He, Yongqun

    2015-11-27

    A recombinant vector vaccine uses an attenuated virus, bacterium, or parasite as the carrier to express a heterologous antigen(s). Many recombinant vaccine vectors and related vaccines have been developed and extensively investigated. To compare and better understand recombinant vectors and vaccines, we have generated Vaxvec (http://www.violinet.org/vaxvec), the first web-based database that stores various recombinant vaccine vectors and those experimentally verified vaccines that use these vectors. Vaxvec has now included 59 vaccine vectors that have been used in 196 recombinant vector vaccines against 66 pathogens and cancers. These vectors are classified to 41 viral vectors, 15 bacterial vectors, 1 parasitic vector, and 1 fungal vector. The most commonly used viral vaccine vectors are double-stranded DNA viruses, including herpesviruses, adenoviruses, and poxviruses. For example, Vaxvec includes 63 poxvirus-based recombinant vaccines for over 20 pathogens and cancers. Vaxvec collects 30 recombinant vector influenza vaccines that use 17 recombinant vectors and were experimentally tested in 7 animal models. In addition, over 60 protective antigens used in recombinant vector vaccines are annotated and analyzed. User-friendly web-interfaces are available for querying various data in Vaxvec. To support data exchange, the information of vaccine vectors, vaccines, and related information is stored in the Vaccine Ontology (VO). Vaxvec is a timely and vital source of vaccine vector database and facilitates efficient vaccine vector research and development.

  3. Protective efficacy of a recombinant BAC clone of Marek's disease virus containing REV-LTR

    Science.gov (United States)

    Insertion of reticuloendotheliosis virus (REV) long-terminal repeat (LTR) into a bacterial artificial chromosome (BAC) clone of a very virulent strain of Marek’s disease (MD) virus (MDV), Md5 (Kim et al, 2011) rendered the resultant recombinant virus termed rMd5 REV-LTR BAC fully attenuated at passa...

  4. Enhancement of tumor cell death by combining cisplatin with an oncolytic adenovirus carrying MDA-7/IL-24

    Institute of Scientific and Technical Information of China (English)

    Yu-mei WU; Kang-jian ZHANG; Xue-tian YUE; Yi-qiang WANG; Yi YANG; Gong-chu LI; Na LI; Yi-gang WANG

    2009-01-01

    Aim: The aim of this study was to creatively implement a novel chemo-gene-virotherapeutic strategy and further strengthen the antitumor effect in cancer cells by the combined use of ZD55-IL-24 and cisplatin. Methods: ZD55-IL-24 is an oncolytic adenovirus that harbors interleukin 24 (IL-24), which has a strong antitumor effect and was identified and evaluated by PCR, RT-PCR, and Western blot analysis. Enhancement of cancer cell death using a combination of ZD55-IL-24 and cisplatin was assessed in several cancer cell lines by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and cytopathic effect (CPE) assay. Apoptosis induction by treatment with ZD55-IL-24 and/or cisplatin was detected in BEL7404 and SMMC7721 by morphological evaluation, apoptotic cell staining, and flow cytometry analysis. In addition, negative effects on normal cells were evaluated in the L-02 cell line using the MTT assay,the CPE assay, morphological evaluation, apoptotic cell staining, and flow cytometry analysis. Results: The combination of ZD55-IL-24 and cisplatin, which is superior to ZD55-IL-24, cisplatin, and ZD55-EGFP, as well as ZD55-EGFP plus cisplatin, resulted in a significantly increased effect. Most importantly, conjugation of ZD55-IL-24 with cisplatin had toxic effects equal to that of cisplatin and did not have overlapping toxicities in normal cells.Conclusions: This study showed that ZD55-IL-24 conjugated with cisplatin exhibited a remarkably increased cytotoxic and apoptosis-inducing effect in cancer cells and significantly reduced the toxicity in normal cells through the use of a reduced dose.

  5. A combinational therapy of EGFR-CAR NK cells and oncolytic herpes simplex virus 1 for breast cancer brain metastases.

    Science.gov (United States)

    Chen, Xilin; Han, Jianfeng; Chu, Jianhong; Zhang, Lingling; Zhang, Jianying; Chen, Charlie; Chen, Luxi; Wang, Youwei; Wang, Hongwei; Yi, Long; Elder, J Bradley; Wang, Qi-En; He, Xiaoming; Kaur, Balveen; Chiocca, E Antonio; Yu, Jianhua

    2016-05-10

    Breast cancer brain metastases (BCBMs) are common in patients with metastatic breast cancer and indicate a poor prognosis. These tumors are especially resistant to currently available treatments due to multiple factors. However, the combination of chimeric antigen receptor (CAR)-modified immune cells and oncolytic herpes simplex virus (oHSV) has not yet been explored in this context. In this study, NK-92 cells and primary NK cells were engineered to express the second generation of EGFR-CAR. The efficacies of anti-BCBMs of EGFR-CAR NK cells, oHSV-1, and their combination were tested in vitro and in a breast cancer intracranial mouse model. In vitro, compared with mock-transduced NK-92 cells or primary NK cells, EGFR-CAR-engineered NK-92 cells and primary NK cells displayed enhanced cytotoxicity and IFN-γ production when co-cultured with breast cancer cell lines MDA-MB-231, MDA-MB-468, and MCF-7. oHSV-1 alone was also capable of lysing and destroying these cells. However, a higher cytolytic effect of EGFR-CAR NK-92 cells was observed when combined with oHSV-1 compared to the monotherapies. In the mice intracranially pre-inoculated with EGFR-expressing MDA-MB-231 cells, intratumoral administration of either EGFR-CAR-transduced NK-92 cells or oHSV-1 mitigated tumor growth. Notably, the combination of EGFR-CAR NK-92 cells with oHSV-1 resulted in more efficient killing of MDA-MB-231 tumor cells and significantly longer survival of tumor-bearing mice when compared to monotherapies. These results demonstrate that regional administration of EGFR-CAR NK-92 cells combined with oHSV-1 therapy is a potentially promising strategy to treat BCBMs.

  6. Bacterial Recombineering: Genome Engineering via Phage-Based Homologous Recombination.

    Science.gov (United States)

    Pines, Gur; Freed, Emily F; Winkler, James D; Gill, Ryan T

    2015-11-20

    The ability to specifically modify bacterial genomes in a precise and efficient manner is highly desired in various fields, ranging from molecular genetics to metabolic engineering and synthetic biology. Much has changed from the initial realization that phage-derived genes may be employed for such tasks to today, where recombineering enables complex genetic edits within a genome or a population. Here, we review the major developments leading to recombineering becoming the method of choice for in situ bacterial genome editing while highlighting the various applications of recombineering in pushing the boundaries of synthetic biology. We also present the current understanding of the mechanism of recombineering. Finally, we discuss in detail issues surrounding recombineering efficiency and future directions for recombineering-based genome editing.

  7. A bidirectional Tet-dependent promotor construct regulating the expression of E1A for tight control of oncolytic adenovirus replication.

    Science.gov (United States)

    Fechner, Henry; Wang, Xiaomin; Picó, Almudena Hurtado; Wildner, Judith; Suckau, Lennart; Pinkert, Sandra; Sipo, Isaac; Weger, Stefan; Poller, Wolfgang

    2007-01-20

    Tight regulation of oncolytic adenoviruses (oAdV) represents an important requirement for their safe application. Here we describe a new doxycycline (Dox)-dependent oAdV with a bidirectional expression cassette, which drives the expression of the reverse tetracycline-controlled transactivator (rtTA(s)-M2) from a lung tumor-specific promoter and, in the opposite direction, the expression of the adenoviral E1A gene from a second generation TetO(7) sequence linked to an isolated TATA box. In H441 lung cancer cells, this oAdV showed a strictly Dox-dependent E1A expression, adenoviral replication, cell killing activity and a 450-fold induction of progeny virus production. The virus could be shut off again by withdrawal of Dox and, in contrast to a control oAdV expressing E1A directly from the SP-B promoter, did not replicate in non-target cells. However, the absolute values of virus production and the cell killing activity in the presence of the inducer were still reduced as compared to the control oAdV. The results demonstrate, for the first time, Dox-dependent oAdV replication from a single adenoviral vector genome. Future improvement of the Dox-dependent E1A regulation cassette should lead to the generation of an oAdV well suited to meet the demands for a highly regulated and efficient oncolytic virus for in vivo applications.

  8. Pancreatic adenocarcinoma upregulated factor (PAUF) confers resistance to pancreatic cancer cells against oncolytic parvovirus H-1 infection through IFNA receptor-mediated signaling.

    Science.gov (United States)

    Kaowinn, Sirichat; Cho, Il-Rae; Moon, Jeong; Jun, Seung Won; Kim, Chang Seok; Kang, Ho Young; Kim, Manbok; Koh, Sang Seok; Chung, Young-Hwa

    2015-04-01

    Pancreatic adenocarcinoma upregulated factor (PAUF), a novel oncogene, plays a crucial role in the development of pancreatic cancer, including its metastasis and proliferation. Therefore, PAUF-expressing pancreatic cancer cells could be important targets for oncolytic virus-mediated treatment. Panc-1 cells expressing PAUF (Panc-PAUF) showed relative resistance to parvovirus H-1 infection compared with Panc-1 cells expressing an empty vector (Panc-Vec). Of interest, expression of type I IFN-α receptor (IFNAR) was higher in Panc-PAUF cells than in Panc-Vec cells. Increased expression of IFNAR in turn increased the activation of Stat1 and Tyk2 in Panc-PAUF cells compared with that in Panc-Vec cells. Suppression of Tyk2 and Stat1, which are important downstream molecules for IFN-α signaling, sensitized pancreatic cancer cells to parvovirus H-1-mediated apoptosis. Further, constitutive suppression of PAUF sensitized Bxpc3 pancreatic cancer cells to parvovirus H-1 infection. Taken together, these results suggested that PAUF conferred resistance to pancreatic cancer cells against oncolytic parvovirus H-1 infection through IFNAR-mediated signaling.

  9. Viability Reduction and Rac1 Gene Downregulation of Heterogeneous Ex-Vivo Glioma Acute Slice Infected by the Oncolytic Newcastle Disease Virus Strain V4UPM

    Directory of Open Access Journals (Sweden)

    Zulkifli Mustafa

    2013-01-01

    Full Text Available Oncolytic viruses have been extensively evaluated for anticancer therapy because this virus preferentially infects cancer cells without interfering with normal cells. Newcastle Disease Virus (NDV is an avian virus and one of the intensively studied oncolytic viruses affecting many types of cancer including glioma. Nevertheless, the capability of NDV infection on heterogeneous glioma tissue in a cerebrospinal fluid atmosphere has never been reported. Recently, Rac1 is reported to be required for efficient NDV replication in human cancer cells and established a link between tumourigenesis and sensitivity to NDV. Rac1 is a member of the Rho GTPases involved in the regulation of the cell migration and cell-cycle progression. Rac1 knockdown leads to significant inhibition of viral replication. In this work, we demonstrated that NDV treatment led to significant reduction of tumour tissue viability of freshly isolated heterogeneous human brain tumour slice, known as an ex vivo glioma acute slice (EGAS. Analysis of gene expression indicated that reduced tissue viability was associated with downregulation of Rac1. However, the viability reduction was not persistent. We conclude that NDV treatment induced EGAS viability suppression, but subsequent downregulation of Rac1 gene may reduce the NDV replication and lead to regrowth of EGAS tissue.

  10. Chapter three--Syrian hamster as an animal model to study oncolytic adenoviruses and to evaluate the efficacy of antiviral compounds.

    Science.gov (United States)

    Wold, William S M; Toth, Karoly

    2012-01-01

    The Syrian (golden) hamster (Mesocricetus auratus) has served as a useful model for different aspects of biology for at least 50 years, and its use has been expanding recently. In earlier years, among other things, it was a model for cancer development. More recently, it has become a model for many different infectious diseases. It has also become an alternative model for the study of oncolytic adenovirus vectors for cancer gene therapy. Among several other human pathogens, the hamster is permissive for the replication of human species C adenoviruses, which are the parental virus for the majority of adenovirus vectors in use today. These vectors replicate in some of the established hamster tumor cell lines that can be used to generate tumors in vivo, that is, one can study oncolytic (replication competent) adenoviruses in a permissive, immunocompetent model. This has afforded the opportunity to study the effect of the host immune system on the vector-infected tumor and has allowed the use of a more relevant animal model to determine the safety and biodistribution of replication-competent adenoviruses. The hamster has also been used to evaluate antiviral compounds and vaccines against many viruses, including adenoviruses, flaviviruses, alphaviruses, arenaviruses, bunyaviruses, and paramyxoviruses.

  11. Preclinical Evaluation of Oncolytic Δγ134.5 Herpes Simplex Virus Expressing Interleukin-12 for Therapy of Breast Cancer Brain Metastases

    Directory of Open Access Journals (Sweden)

    James J. Cody

    2012-01-01

    Full Text Available The metastasis of breast cancer to the brain and central nervous system (CNS is a problem of increasing importance. As improving treatments continue to extend patient survival, the incidence of CNS metastases from breast cancer is on the rise. New treatments are needed, as current treatments are limited by deleterious side effects and are generally palliative. We have previously described an oncolytic herpes simplex virus (HSV, designated M002, which lacks both copies of the γ134.5 neurovirulence gene and carries a murine interleukin 12 (IL-12 expression cassette, and have validated its antitumor efficacy in a variety of preclinical models of primary brain tumors. However, M002 has not been yet evaluated for use against metastatic brain tumors. Here, we demonstrate the following: both human breast cancer and murine mammary carcinoma cells support viral replication and IL-12 expression from M002; M002 replicates in and destroys breast cancer cells from a variety of histological subtypes, including “triple-negative” and HER2 overexpressing; M002 improves survival in an immunocompetent model more effectively than does a non-cytokine control virus. Thus, we conclude from this proof-of-principle study that a γ134.5-deleted IL-12 expressing oncolytic HSV may be a potential new therapy for breast cancer brain metastases.

  12. Recombinant Collagenlike Proteins

    Science.gov (United States)

    Fertala, Andzej

    2007-01-01

    A group of collagenlike recombinant proteins containing high densities of biologically active sites has been invented. The method used to express these proteins is similar to a method of expressing recombinant procollagens and collagens described in U. S. Patent 5,593,859, "Synthesis of human procollagens and collagens in recombinant DNA systems." Customized collagenous proteins are needed for biomedical applications. In particular, fibrillar collagens are attractive for production of matrices needed for tissue engineering and drug delivery. Prior to this invention, there was no way of producing customized collagenous proteins for these and other applications. Heretofore, collagenous proteins have been produced by use of such biological systems as yeasts, bacteria, and transgenic animals and plants. These products are normal collagens that can also be extracted from such sources as tendons, bones, and hides. These products cannot be made to consist only of biologically active, specific amino acid sequences that may be needed for specific applications. Prior to this invention, it had been established that fibrillar collagens consist of domains that are responsible for such processes as interaction with cells, binding of growth factors, and interaction with a number of structural proteins present in the extracellular matrix. A normal collagen consists of a sequence of domains that can be represented by a corresponding sequence of labels, e.g., D1D2D3D4. A collagenlike protein of the present invention contains regions of collagen II that contain multiples of a single domain (e.g., D1D1D1D1 or D4D4D4D4) chosen for its specific biological activity. By virtue of the multiplicity of the chosen domain, the density of sites having that specific biological activity is greater than it is in a normal collagen. A collagenlike protein according to this invention can thus be made to have properties that are necessary for tissue engineering.

  13. Dielectronic recombination theory

    Energy Technology Data Exchange (ETDEWEB)

    LaGattuta, K.J.

    1991-12-31

    A theory now in wide use for the calculation of dielectronic recombination cross sections ({sigma}{sup DR}) and rate coefficients ({alpha}{sup DR}) was one introduced originally by Feshbach for nuclear physics applications, and then later adapted for atomic scattering problems by Hahn. In the following, we briefly review this theory in a very general form, which allows one to account for the effects of overlapping and interacting resonances, as well as continuum-continuum coupling. An extension of our notation will then also allow for the inclusion of the effects of direct radiative recombination, along with a treatment of the interference between radiative and dielectronic recombination. Other approaches to the calculation of {sigma}{sup DR} have been described by Fano and by Seaton. We will not consider those theories here. Calculations of {alpha}{sup DR} have progressed considerably over the last 25 years, since the early work of Burgess. Advances in the reliability of theoretical predictions have also been promoted recently b a variety of direct laboratory measurements of {sigma}{sup DR}. While the measurements of {sigma}{sup DR} for {delta}n {ne} 0 excitations have tended to agree very well with calculations, the case of {delta}n = 0 has been much problematic. However, by invoking a mechanism originally proposed by Jacobs, which takes into account the effect of stray electric fields on high Rydberg states (HRS) participating in the DR process, new calculations have improved the agreement between theory and experiment for these cases. Nevertheless, certain discrepancies still remain.

  14. Engineered measles virus Edmonston strain used as a novel oncolytic viral system against human hepatoblastoma

    Directory of Open Access Journals (Sweden)

    Zhang Shu-Cheng

    2012-09-01

    Full Text Available Abstract Background Hepatoblastoma (HB is the most common primary, malignant pediatric liver tumor in children. The treatment results for affected children have markedly improved in recent decades. However, the prognosis for high-risk patients who have extrahepatic extensions, invasion of the large hepatic veins, distant metastases and very high alpha-fetoprotein (AFP serum levels remains poor. There is an urgent need for the development of novel therapeutic approaches. Methods An attenuated strain of measles virus, derived from the Edmonston vaccine lineage, was genetically engineered to produce carcinoembryonic antigen (CEA. We investigated the antitumor potential of this novel viral agent against human HB both in vitro and in vivo. Results Infection of the Hep2G and HUH6 HB cell lines, at multiplicities of infection (MOIs ranging from 0.01 to 1, resulted in a significant cytopathic effect consisting of extensive syncytia formation and massive cell death at 72–96 h after infection. Both of the HB lines overexpressed the measles virus receptor CD46 and supported robust viral replication, which correlated with CEA production. The efficacy of this approach in vivo was examined in murine Hep2G xenograft models. Flow cytometry assays indicated an apoptotic mechanism of cell death. Intratumoral administration of MV-CEA resulted in statistically significant delay of tumor growth and prolongation of survival. Conclusions The engineered measles virus Edmonston strain MV-CEA has potent therapeutic efficacy against HB cell lines and xenografts. Trackable measles virus derivatives merit further exploration in HB treatment.

  15. Cell biology of mitotic recombination

    DEFF Research Database (Denmark)

    Lisby, Michael; Rothstein, Rodney

    2015-01-01

    Homologous recombination provides high-fidelity DNA repair throughout all domains of life. Live cell fluorescence microscopy offers the opportunity to image individual recombination events in real time providing insight into the in vivo biochemistry of the involved proteins and DNA molecules...... of this review include the stoichiometry and dynamics of recombination complexes in vivo, the choreography of assembly and disassembly of recombination proteins at sites of DNA damage, the mobilization of damaged DNA during homology search, and the functional compartmentalization of the nucleus with respect...... as well as the cellular organization of the process of homologous recombination. Herein we review the cell biological aspects of mitotic homologous recombination with a focus on Saccharomyces cerevisiae and mammalian cells, but will also draw on findings from other experimental systems. Key topics...

  16. Expression of recombinant antibodies.

    Science.gov (United States)

    Frenzel, André; Hust, Michael; Schirrmann, Thomas

    2013-01-01

    Recombinant antibodies are highly specific detection probes in research, diagnostics, and have emerged over the last two decades as the fastest growing class of therapeutic proteins. Antibody generation has been dramatically accelerated by in vitro selection systems, particularly phage display. An increasing variety of recombinant production systems have been developed, ranging from Gram-negative and positive bacteria, yeasts and filamentous fungi, insect cell lines, mammalian cells to transgenic plants and animals. Currently, almost all therapeutic antibodies are still produced in mammalian cell lines in order to reduce the risk of immunogenicity due to altered, non-human glycosylation patterns. However, recent developments of glycosylation-engineered yeast, insect cell lines, and transgenic plants are promising to obtain antibodies with "human-like" post-translational modifications. Furthermore, smaller antibody fragments including bispecific antibodies without any glycosylation are successfully produced in bacteria and have advanced to clinical testing. The first therapeutic antibody products from a non-mammalian source can be expected in coming next years. In this review, we focus on current antibody production systems including their usability for different applications.

  17. Semiactive control for vibration attenuation

    Energy Technology Data Exchange (ETDEWEB)

    Leitmann, G. [Univ. of California, Berkeley, CA (United States). Coll. of Engineering

    1994-12-31

    With the advent of materials, such as electrorheological fluids, whose material properties can be altered rapidly by means of external stimuli, employing such materials as actuators for the controlled attenuation of undesirable vibrations is now possible. Such control schemes are dubbed semiactive in that they attenuate vibrations whether applied actively or passively. The author investigates various such control schemes, allowing for both separate and joint control of the stiffness and damping characteristics of the material.

  18. RECOMBINANT HORSERADISH PEROXIDASE FOR ANALYTICAL APPLICATIONS

    OpenAIRE

    2013-01-01

    The article deals with prospects of using recombinant horseradish peroxidase in analytical biochemistry and biotechnology. Problems of recombinant horseradish peroxidase cloning in different expression systems, possible approaches to their solution, advantages of recombinant recombinant horseradish peroxidase and recombinant horseradish peroxidase-fusion proteins for immunoassays are considered. Possibility for development of mediatorless bienzyme biosensor for peroxide and metabolites, yield...

  19. Bimolecular recombination in organic photovoltaics.

    Science.gov (United States)

    Lakhwani, Girish; Rao, Akshay; Friend, Richard H

    2014-01-01

    The recombination of electrons and holes is a major loss mechanism in photovoltaic devices that controls their performance. We review scientific literature on bimolecular recombination (BR) in bulk heterojunction organic photovoltaic devices to bring forward existing ideas on the origin and nature of BR and highlight both experimental and theoretical work done to quantify its extent. For these systems, Langevin theory fails to explain BR, and recombination dynamics turns out to be dependent on mobility, temperature, electric field, charge carrier concentration, and trapped charges. Relationships among the photocurrent, open-circuit voltage, fill factor, and morphology are discussed. Finally, we highlight the recent emergence of a molecular-level picture of recombination, taking into account the spin and delocalization of charges. Together with the macroscopic picture of recombination, these new insights allow for a comprehensive understanding of BR and provide design principles for future materials and devices.

  20. HCCS1-armed, quadruple-regulated oncolytic adenovirus specific for liver cancer as a cancer targeting gene-viro-therapy strategy

    Directory of Open Access Journals (Sweden)

    Xu Hai-Neng

    2011-11-01

    Full Text Available Abstract Background In previously published studies, oncolytic adenovirus-mediated gene therapy has produced good results in targeting cancer cells. However, safety and efficacy, the two most important aspects in cancer therapy, remain serious challenges. The specific expression or deletion of replication related genes in an adenovirus has been frequently utilized to regulate the cancer cell specificity of a virus. Accordingly, in this study, we deleted 24 bp in E1A (bp924-bp947 and the entirety of E1B, including those genes encoding E1B 55kDa and E1B19kDa. We used the survivin promoter (SP to control E1A in order to construct a new adenovirus vector named Ad.SP.E1A(Δ24.ΔE1B (briefly Ad.SPDD. HCCS1 (hepatocellular carcinoma suppressor 1 is a novel tumor suppressor gene that is able to specifically induce apoptosis in cancer cells. The expression cassette AFP-HCCS1-WPRE-SV40 was inserted into Ad.SPDD to form Ad.SPDD-HCCS1, enabling us to improve the safety and efficacy of oncolytic-mediated gene therapy for liver cancer. Results Ad.SPDD showed a decreased viral yield and less toxicity in normal cells but enhanced toxicity in liver cancer cells, compared with the cancer-specific adenovirus ZD55 (E1B55K deletion. Ad.SPDD-HCCS1 exhibited a potent anti-liver-cancer ability and decreased toxicity in vitro. Ad.SPDD-HCCS1 also showed a measurable capacity to inhibit Huh-7 xenograft tumor growth on nude mice. The underlying mechanism of Ad.SPDD-HCCS1-induced liver cancer cell death was found to be via the mitochondrial apoptosis pathway. Conclusions These results demonstrate that Ad.SPDD-HCCS1 was able to elicit reduced toxicity and enhanced efficacy both in vitro and in vivo compared to a previously constructed oncolytic adenovirus. Ad.SPDD-HCCS1 could be a promising candidate for liver cancer therapy.

  1. Photoacoustic Imaging Taking into Account Attenuation

    CERN Document Server

    Kowar, Richard

    2010-01-01

    First, we review existing attenuation models and discuss their causality properties, which we believe to be essential for algorithms for inversion with attenuated data. Then, we survey causality properties of common attenuation models. We also derive integro-differential equations which the attenuated waves are satisfying. In addition we discuss the ill--conditionness of the inverse problem for calculating the unattenuated wave from the attenuated one.

  2. Attenuation in Superconducting Circular Waveguides

    Directory of Open Access Journals (Sweden)

    K. H. Yeap

    2016-09-01

    Full Text Available We present an analysis on wave propagation in superconducting circular waveguides. In order to account for the presence of quasiparticles in the intragap states of a superconductor, we employ the characteristic equation derived from the extended Mattis-Bardeen theory to compute the values of the complex conductivity. To calculate the attenuation in a circular waveguide, the tangential fields at the boundary of the wall are first matched with the electrical properties (which includes the complex conductivity of the wall material. The matching of fields with the electrical properties results in a set of transcendental equations which is able to accurately describe the propagation constant of the fields. Our results show that although the attenuation in the superconducting waveguide above cutoff (but below the gap frequency is finite, it is considerably lower than that in a normal waveguide. Above the gap frequency, however, the attenuation in the superconducting waveguide increases sharply. The attenuation eventually surpasses that in a normal waveguide. As frequency increases above the gap frequency, Cooper pairs break into quasiparticles. Hence, we attribute the sharp rise in attenuation to the increase in random collision of the quasiparticles with the lattice structure.

  3. Riboswitch-mediated Attenuation of Transgene Cytotoxicity Increases Adeno-associated Virus Vector Yields in HEK-293 Cells.

    Science.gov (United States)

    Strobel, Benjamin; Klauser, Benedikt; Hartig, Jörg S; Lamla, Thorsten; Gantner, Florian; Kreuz, Sebastian

    2015-10-01

    Cytotoxicity of transgenes carried by adeno-associated virus (AAV) vectors might be desired, for instance, in oncolytic virotherapy or occur unexpectedly in exploratory research when studying sparsely characterized genes. To date, most AAV-based studies use constitutively active promoters (e.g., the CMV promoter) to drive transgene expression, which often hampers efficient AAV production due to cytotoxic, antiproliferative, or unknown transgene effects interfering with producer cell performance. Therefore, we explored artificial riboswitches as novel tools to control transgene expression during AAV production in mammalian cells. Our results demonstrate that the guanine-responsive GuaM8HDV aptazyme efficiently attenuates transgene expression and associated detrimental effects, thereby boosting AAV vector yields up to 23-fold after a single addition of guanine. Importantly, riboswitch-harboring vectors preserved their ability to express functional transgene at high levels in the absence of ligand, as demonstrated in a mouse model of AAV-TGFβ1-induced pulmonary fibrosis. Thus, our study provides the first application-ready biotechnological system-based on aptazymes, which should enable high viral vector yields largely independent of the transgene used. Moreover, the RNA-intrinsic, small-molecule regulatable mode of action of riboswitches provides key advantages over conventional transcription factor-based regulatory systems. Therefore, such riboswitch vectors might be ultimately applied to temporally control therapeutic transgene expression in vivo.

  4. Analysis of interchromosomal mitotic recombination.

    Science.gov (United States)

    McGill, C B; Shafer, B K; Higgins, D R; Strathern, J N

    1990-07-01

    A novel synthetic locus is described that provides a simple assay system for characterizing mitotic recombinants. The locus consists of the TRP1 and HIS3 genes inserted into chromosome III of S. cerevisiae between the CRY1 and MAT loci. Defined trp1 and his3 alleles have been generated that allow the selection of interchromosomal recombinants in this interval. Trp+ or His+ recombinants can be divided into several classes based on coupling of the other alleles in the interval. The tight linkage of the CRY1 and MAT loci, combined with the drug resistance and cell type phenotypes that they respectively control, facilitates the classification of the recombinants without resorting to tetrad dissection. We present the distribution of spontaneous recombinants among the classes defined by this analysis. The data suggest that the recombination intermediate can have regions of symmetric strand exchange and that co-conversion tracts can extend over 1-3 kb. Continuous conversion tracts are favored over discontinuous tracts. The distribution among the classes defined by this analysis is altered in recombinants induced by UV irradiation.

  5. X-Ray Attenuation Cell

    Energy Technology Data Exchange (ETDEWEB)

    Ryutov, D.; Toor, A.

    2000-03-03

    To minimize the pulse-to-pulse variation, the LCLS FEL must operate at saturation, i.e. 10 orders of magnitude brighter spectral brilliance than 3rd-generation light sources. At this intensity, ultra-high vacuums and windowless transport are required. Many of the experiments, however, will need to be conducted at a much lower intensity thereby requiring a reliable means to reduce the x-ray intensity by many orders of magnitude without increasing the pulse-to-pulse variation. In this report we consider a possible solution for controlled attenuation of the LCLS x-ray radiation. We suggest using for this purpose a windowless gas-filled cell with the differential pumping. Although this scheme is easily realizable in principle, it has to be demonstrated that the attenuator can be made short enough to be practical and that the gas loads delivered to the vacuum line of sight (LOS) are acceptable. We are not going to present a final, optimized design. Instead, we will provide a preliminary analysis showing that the whole concept is robust and is worth further study. The spatial structure of the LCLS x-ray pulse at the location of the attenuator is shown in Fig. 1. The central high-intensity component, due to the FEL, has a FWHM of {approx}100 {micro}m. A second component, due to the undulator's broad band spontaneous radiation is seen as a much lower intensity ''halo'' with a FWHM of 1 mm. We discuss two versions of the attenuation cell. The first is directed towards a controlled attenuation of the FEL up to the 4 orders of magnitude in the intensity, with the spontaneous radiation halo being eliminated by collimators. In the second version, the spontaneous radiation is not sacrificed but the FEL component (as well as the first harmonic of the spontaneous radiation) gets attenuated by a more modest factor up to 100. We will make all the estimates assuming that the gas used in the attenuator is Xenon and that the energy of the FEL is 8.25 keV. At

  6. Genetically attenuated Trypanosoma cruzi parasites as a potential vaccination tool.

    Science.gov (United States)

    Pérez Brandan, Cecilia; Basombrío, Miguel Ángel

    2012-01-01

    Chagas disease is the clinical manifestation of the infection produced by the parasite Trypanosoma cruzi. Currently there is no vaccine to prevent this disease and the protection attained with vaccines containing non-replicating parasites is limited. Genetically attenuated trypanosomatid parasites can be obtained by deletion of selected genes. Gene deletion takes advantage of the fact that this parasite can undergo homologous recombination between endogenous and foreign DNA sequences artificially introduced in the cells. This approach facilitated the discovery of several unknown gene functions, as well as allowing us to speculate about the potential for genetically attenuated live organisms as experimental immunogens. Vaccination with live attenuated parasites has been used effectively in mice to reduce parasitemia and histological damage, and in dogs, to prevent vector-delivered infection in the field. However, the use of live parasites as immunogens is controversial due to the risk of reversion to a virulent phenotype. Herein, we present our results from experiments on genetic manipulation of two T. cruzi strains to produce parasites with impaired replication and infectivity, and using the mutation of the dhfr-ts gene as a safety device against reversion to virulence.

  7. Resistance to oncolytic myxoma virus therapy in nf1(-/-)/trp53(-/-) syngeneic mouse glioma models is independent of anti-viral type-I interferon.

    Science.gov (United States)

    Zemp, Franz J; McKenzie, Brienne A; Lun, Xueqing; Maxwell, Lori; Reilly, Karlyne M; McFadden, Grant; Yong, V Wee; Forsyth, Peter A

    2013-01-01

    Despite promising preclinical studies, oncolytic viral therapy for malignant gliomas has resulted in variable, but underwhelming results in clinical evaluations. Of concern are the low levels of tumour infection and viral replication within the tumour. This discrepancy between the laboratory and the clinic could result from the disparity of xenograft versus syngeneic models in determining in vivo viral infection, replication and treatment efficacy. Here we describe a panel of primary mouse glioma lines derived from Nf1 (+/-) Trp53 (+/-) mice in the C57Bl/6J background for use in the preclinical testing of the oncolytic virus Myxoma (MYXV). These lines show a range of susceptibility to MYXV replication in vitro, but all succumb to viral-mediated cell death. Two of these lines orthotopically grafted produced aggressive gliomas. Intracranial injection of MYXV failed to result in sustained viral replication or treatment efficacy, with minimal tumour infection that was completely resolved by 7 days post-infection. We hypothesized that the stromal production of Type-I interferons (IFNα/β) could explain the resistance seen in these models; however, we found that neither the cell lines in vitro nor the tumours in vivo produce any IFNα/β in response to MYXV infection. To confirm IFNα/β did not play a role in this resistance, we ablated the ability of tumours to respond to IFNα/β via IRF9 knockdown, and generated identical results. Our studies demonstrate that these syngeneic cell lines are relevant preclinical models for testing experimental glioma treatments, and show that IFNα/β is not responsible for the MYXV treatment resistance seen in syngeneic glioma models.

  8. Preferential colonization of metastases by oncolytic vaccinia virus strain GLV-1h68 in a human PC-3 prostate cancer model in nude mice.

    Directory of Open Access Journals (Sweden)

    Ulrike Donat

    Full Text Available Recently, we showed that the oncolytic vaccinia virus GLV-1h68 has a significant therapeutic potential in treating lymph node metastases of human PC-3 prostate carcinoma in tumor xenografts. In this study, underlying mechanisms of the virus-mediated metastases reduction were analyzed. Immunohistochemistry demonstrated that virus-treatment resulted in a drastically decrease of blood and lymph vessels, representing essential routes for PC-3 cell migration, in both tumors and metastases. Thus, GLV-1h68 drastically reduced essential routes for the metastatic spread of PC-3 cells. Furthermore, analysis of viral distribution in GLV-1h68-injected tumor-bearing mice by plaque assays, revealed significantly higher virus titers in metastases compared to solid tumors. To elucidate conditions potentially mediating the preferential viral colonization and eradication of metastases, microenvironmental components of uninfected tumors and metastases were compared by microscopic studies. These analyses revealed that PC-3 lymph node metastases showed increased vascular permeability, higher proliferation status of tumor cells as determined by BrdU- and Ki-67 assays and lesser necrosis of PC-3 cells than solid tumors. Moreover, an increased number of immune cells (MHCII(+/CD68(+ macrophages, MHCII(+/CD19(+ B lymphocytes combined with an up-regulated expression of pro-inflammatory cytokines was observed in metastases in comparison to primary PC-3 tumors. We propose that these microenvironmental components mediated the metastatic tropism of GLV-1h68. Therefore, vaccinia virus-based oncolytic virotherapy might offer a novel treatment of metastatic prostate carcinomas in humans.

  9. Resistance to oncolytic myxoma virus therapy in nf1(-/-/trp53(-/- syngeneic mouse glioma models is independent of anti-viral type-I interferon.

    Directory of Open Access Journals (Sweden)

    Franz J Zemp

    Full Text Available Despite promising preclinical studies, oncolytic viral therapy for malignant gliomas has resulted in variable, but underwhelming results in clinical evaluations. Of concern are the low levels of tumour infection and viral replication within the tumour. This discrepancy between the laboratory and the clinic could result from the disparity of xenograft versus syngeneic models in determining in vivo viral infection, replication and treatment efficacy. Here we describe a panel of primary mouse glioma lines derived from Nf1 (+/- Trp53 (+/- mice in the C57Bl/6J background for use in the preclinical testing of the oncolytic virus Myxoma (MYXV. These lines show a range of susceptibility to MYXV replication in vitro, but all succumb to viral-mediated cell death. Two of these lines orthotopically grafted produced aggressive gliomas. Intracranial injection of MYXV failed to result in sustained viral replication or treatment efficacy, with minimal tumour infection that was completely resolved by 7 days post-infection. We hypothesized that the stromal production of Type-I interferons (IFNα/β could explain the resistance seen in these models; however, we found that neither the cell lines in vitro nor the tumours in vivo produce any IFNα/β in response to MYXV infection. To confirm IFNα/β did not play a role in this resistance, we ablated the ability of tumours to respond to IFNα/β via IRF9 knockdown, and generated identical results. Our studies demonstrate that these syngeneic cell lines are relevant preclinical models for testing experimental glioma treatments, and show that IFNα/β is not responsible for the MYXV treatment resistance seen in syngeneic glioma models.

  10. Transduction and oncolytic profile of a potent replication-competent adenovirus 11p vector (RCAd11pGFP in colon carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Jim Silver

    Full Text Available Replication-competent adenovirus type 5 (Ad5 vectors promise to be more efficient gene delivery vehicles than their replication-deficient counterparts, and chimeric Ad5 vectors that are capable of targeting CD46 are more effective than Ad5 vectors with native fibers. Although several strategies have been used to improve gene transduction and oncolysis, either by modifying their tropism or enhancing their replication capacity, some tumor cells are still relatively refractory to infection by chimeric Ad5. The oncolytic effects of the vectors are apparent in certain tumors but not in others. Here, we report the biological and oncolytic profiles of a replication-competent adenovirus 11p vector (RCAd11pGFP in colon carcinoma cells. CD46 was abundantly expressed in all cells studied; however, the transduction efficiency of RCAd11pGFP varied. RCAd11pGFP efficiently transduced HT-29, HCT-8, and LS174T cells, but it transduced T84 cells, derived from a colon cancer metastasis in the lung, less efficiently. Interestingly, RCAd11p replicated more rapidly in the T84 cells than in HCT-8 and LS174T cells and as rapidly as in HT-29 cells. Cell toxicity and proliferation assays indicated that RCAd11pGFP had the highest cell-killing activities in HT29 and T84 cells, the latter of which also expressed the highest levels of glycoproteins of the carcinoma embryonic antigen (CEA family. In vivo experiments showed significant growth inhibition of T84 and HT-29 tumors in xenograft mice treated with either RCAd11pGFP or Ad11pwt compared to untreated controls. Thus, RCAd11pGFP has a potent cytotoxic effect on colon carcinoma cells.

  11. Testing for recombinant erythropoietin.

    Science.gov (United States)

    Delanghe, Joris R; Bollen, Mathieu; Beullens, Monique

    2008-03-01

    Erythropoietin (Epo) is a glycoprotein hormone that promotes the production of red blood cells. Recombinant human Epo (rhEpo) is illicitly used to improve performance in endurance sports. Doping in sports is discouraged by the screening of athletes for rhEpo. Both direct tests (indicating the presence of exogeneous Epo isoforms) and indirect tests (indicating hematological changes induced by exogenous Epo administration) can be used for Epo detection. At present, the test adopted by the World Anti Doping Agency is based on a combination of isoelectric focusing and double immunoblotting, and distinguishes between endogenous and rhEpo. However, the adopted monoclonal anti-Epo antibodies are not monospecific. Therefore, the test can occasionally lead to the false-positive detection of rhEpo (epoetin-beta) in post-exercise, protein-rich urine, or in case of contamination of the sample with microorganisms. An improved preanalytical care may counteract a lot of these problems. Adaptation of the criteria may be helpful to further refine direct Epo testing. Indirect tests have the disadvantage that they require blood instead of urine samples, but they can be applied to detect a broader range of performance improving techniques which are illicitly used in sports.

  12. Attenuation in silica-based optical fibers

    DEFF Research Database (Denmark)

    Wandel, Marie Emilie

    2006-01-01

    In this thesis on attenuation in silica based optical fibers results within three main topics are reported. Spectral attenuation measurements on transmission fibers are performed in the wide wavelength range 290 nm – 1700 nm. The measured spectral attenuation is analyzed with special emphasis...... on absorption peaks in order to investigate the cause of an unusual high attenuation in a series of transmission fibers. Strong indications point to Ni2+ in octahedral coordination as being the cause of the high attenuation. The attenuation of fibers having a high core refractive index is analyzed and the cause...... of the high attenuation measured in such fibers is described as being due to scattering of light on fluctuations of the core diameter. A novel semi-empirical model for predicting the attenuation of high index fibers is presented. The model is shown to be able to predict the attenuation of high index fibers...

  13. The combined effects of oncolytic reovirus plus Newcastle disease virus and reovirus plus parvovirus on U87 and U373 cells in vitro and in vivo.

    Science.gov (United States)

    Alkassar, Muhannad; Gärtner, Barbara; Roemer, Klaus; Graesser, Friedrich; Rommelaere, Jean; Kaestner, Lars; Haeckel, Isabelle; Graf, Norbert

    2011-09-01

    Previous results had documented oncolytic capacity of reovirus, parvovirus and Newcastle disease virus (NDV) on several tumor cell types. To test whether combinations of these viruses may increase this capacity, human U87- and U373-glioblastoma cells, in vitro or xenografted into immuno-compromised mice, were subjected to simultaneous double infections and analyzed. Our results show that reovirus (serotype-3) plus NDV (Hitcher-B1) and reovirus plus parvovirus-H1 lead to a significant increase in tumor cell killing in vitro in both cell lines (Kruskal-Wallis test, P 95%) after combined infection. These data thus indicate that a synergistic anti-tumor effect can be achieved by the combined infection with oncolytic viruses.

  14. Construction of the recombinant attenuated Salmonella typhimurium under the control of the in vivo inducible nirB promoter%NirB启动子调控下鼠沙门氏菌体内诱导型表达载体的构建

    Institute of Scientific and Technical Information of China (English)

    郭恒; 刘明远; 王光明; 王学林; 李慧萍; 刘学; 张凌怡; 唐艺芝; 高鹤; 杨秀丽; 徐德启

    2011-01-01

    目的 构建遗传稳定性良好的沙门氏菌体内诱导型表达载体.方法 以克隆载体pGB2为基础,将沙门氏菌厌氧启动子PnirB和EGFP基因串联,并在其多克隆位点 MCS 下游引入 rrnbT1T2 转录终止序列,构建沙门氏菌低拷贝体内诱导型表达载体 pGnirB-EGFP-rrnb,电转化入鼠伤寒沙门氏菌phoP/phoQ株,对质粒的稳定性及蛋白表达情况进行检测.结果 含有低拷贝重组质粒的沙门氏菌在缺失抗生素选择压力下盲传100代后质粒稳定性高于95%,在厌氧静置72 h培养后激光共聚焦显微镜下可观察到明显绿色荧光.结论 高度稳定的沙门氏菌体内诱导型表达载体构建成功,为研制以鼠伤寒沙门氏菌为活载体的新型口服疫苗奠定了基础.%Objective Construction of a stable expression vector under the controlof the in vivo inducible nirB promoter in the salm onella typhim urium (S . typhim urium ) .Methods Anaerobic promoter P nir B of salm onella and EGFP were connected into cloning vector pGB2 ,rmbT1T2 transcription termination sequence was inserted into the downstrean of multiply clone sites(M CS) .This plasmid was introduced into S .typhimurium strain phoP/phoQ .The stability of pGB2-based vaccine constructs was determined .The expression of report gene EGFP was detected. Results Salmonella contained pGB2-based plasm id was cultivated for 100 generations without an-tibiotic selection ,the stability of plasm id was up to 95% .Strong green fluorescent can be observed after stationary cultivation for 72 hours under laser scanning confocal microscope. Conclusion The low-copy-number internal-induced eukaryotic expression vector f pG nirB-EGFP-rmb was constructed successfully and stably expressed in salm onella under the control of the in vivo inducible PnirB promoter.It laid a foundation of further study on a new type pre-exposure oral vaccine by using attenuated salm onella as vector.

  15. Cell encoding recombinant human erythropoietin

    Energy Technology Data Exchange (ETDEWEB)

    Beck, A.K.; Withy, R.M.; Zabrecky, J.R.; Masiello, N.C.

    1990-09-04

    This patent describes a C127 cell transformed with a recombinant DNA vector. It comprises: a DNA sequence encoding human erythropoietin, the transformed cell being capable of producing N-linked and O-linked glycosylated human erythropoietin.

  16. Controlled release from recombinant polymers.

    Science.gov (United States)

    Price, Robert; Poursaid, Azadeh; Ghandehari, Hamidreza

    2014-09-28

    Recombinant polymers provide a high degree of molecular definition for correlating structure with function in controlled release. The wide array of amino acids available as building blocks for these materials lend many advantages including biorecognition, biodegradability, potential biocompatibility, and control over mechanical properties among other attributes. Genetic engineering and DNA manipulation techniques enable the optimization of structure for precise control over spatial and temporal release. Unlike the majority of chemical synthetic strategies used, recombinant DNA technology has allowed for the production of monodisperse polymers with specifically defined sequences. Several classes of recombinant polymers have been used for controlled drug delivery. These include, but are not limited to, elastin-like, silk-like, and silk-elastinlike proteins, as well as emerging cationic polymers for gene delivery. In this article, progress and prospects of recombinant polymers used in controlled release will be reviewed.

  17. Perovskite photovoltaics: Slow recombination unveiled

    Science.gov (United States)

    Moser, Jacques-E.

    2017-01-01

    One of the most salient features of hybrid lead halide perovskites is the extended lifetime of their photogenerated charge carriers. This property has now been shown experimentally to originate from a slow, thermally activated recombination process.

  18. Influenza Vaccine, Inactivated or Recombinant

    Science.gov (United States)

    ... die from flu, and many more are hospitalized.Flu vaccine can:keep you from getting flu, make flu ... inactivated or recombinant influenza vaccine?A dose of flu vaccine is recommended every flu season. Children 6 months ...

  19. Three Decades of Recombinant DNA.

    Science.gov (United States)

    Palmer, Jackie

    1985-01-01

    Discusses highlights in the development of genetic engineering, examining techniques with recombinant DNA, legal and ethical issues, GenBank (a national database of nucleic acid sequences), and other topics. (JN)

  20. Josephson tunnel junction microwave attenuator

    DEFF Research Database (Denmark)

    Koshelets, V. P.; Shitov, S. V.; Shchukin, A. V.

    1993-01-01

    A new element for superconducting electronic circuitry-a variable attenuator-has been proposed, designed, and successfully tested. The principle of operation is based on the change in the microwave impedance of a superconductor-insulator-superconductor (SIS) Josephson tunnel junction when dc bias...

  1. Compact plasmonic variable optical attenuator

    DEFF Research Database (Denmark)

    Leosson, Kristjan; Rosenzveig, Tiberiu; Hermannsson, Pétur Gordon

    2008-01-01

    We demonstrate plasmonic nanowire-based thermo-optic variable optical attenuators operating in the 1525-1625 nm wavelength range. The devices have a footprint as low as 1 mm, extinction ratio exceeding 40 dB, driving voltage below 3 V, and full modulation bandwidth of 1 kHz. The polarization...

  2. Heterogeneity in recombinant protein production

    DEFF Research Database (Denmark)

    Schalén, Martin; Johanson, Ted; Lundin, Luisa;

    2012-01-01

    contribute to make a population in a fermenter heterogeneous, resulting in cell-to-cell variation in physiological parameters of the microbial culture. Our study aims at investigating how population heterogeneity and recombinant protein production is affected by environmental gradients in bioreactors...... are simulated in small bioreactors and the population heterogeneity can be visualised by analysing single cells with flow cytometry. This can give new insights to cell physiology and recombinant protein production at the industrial scale....

  3. Inhomogeneous recombinations during cosmic reionization

    OpenAIRE

    Sobacchi, Emanuele; Mesinger, Andrei

    2014-01-01

    By depleting the ionizing photon budget available to expand cosmic HII regions, recombining systems (or Lyman limit systems) can have a large impact during (and following) cosmic reionization. Unfortunately, directly resolving such structures in large-scale reionization simulations is computationally impractical. Instead, here we implement a sub-grid prescription for tracking inhomogeneous recombinations in the intergalactic medium. Building on previous work parameterizing photo-heating feedb...

  4. Plasmid recombination in Haemophilus influenzae

    Energy Technology Data Exchange (ETDEWEB)

    McCarthy, D.

    1982-01-01

    DNA recombination in exponential phase and competent Haemophilus influenzae was measured by an electron microscopic assay that relies on the conversion of plasmid RSF0885 monomers into multimeric forms. Dimer circles were present at a frequency of 2% in plasmid preparations from competent Rd (wild-type) cells; multimers were present at a frequency of 0.2% in preparations from exponential phase cells. Thus, plasmid recombination was stimulated in competent cells. Multimer formation occurred efficiently in cells of the transformation defective mutant rec2, implying that the rec2 gene product is not required for plasmid recombination. However, the absence of multimer plasmids in preparations from competent cells of the transformation defective mutant rec1 suggests that the rec1 gene product is required. Digestion of purified plasmids with restriction endonuclease PvuII, which makes a single cut in the monomer, revealed the presence of recombination intermediates composed of two linear plasmids joined to form two pairs of arms resembling the Greek letter chi. Length measurements of these arms taken from a population of recombination intermediates gave evidence that the plasmids were joined at sites of homology. The distributions of individual DNA strands, at the intersections of the four arms, could be resolved in some recombination intermediates and were of two types. The first type of junction appeared as a single-stranded arm appended to each corner. The second type of junction consisted of a single strand of DNA linking the two linear plasmids at a site of homology. The single-stranded linker was frequently situated at the edge of a short gap on one of the plasmids in the pair. The fine structures of the recombinational joints have been interpreted in terms of previously proposed models of recombination.

  5. Recombinant protein expression in Nicotiana.

    Science.gov (United States)

    Matoba, Nobuyuki; Davis, Keith R; Palmer, Kenneth E

    2011-01-01

    Recombinant protein pharmaceuticals are now widely used in treatment of chronic diseases, and several recombinant protein subunit vaccines are approved for human and veterinary use. With growing demand for complex protein pharmaceuticals, such as monoclonal antibodies, manufacturing capacity is becoming limited. There is increasing need for safe, scalable, and economical alternatives to mammalian cell culture-based manufacturing systems, which require substantial capital investment for new manufacturing facilities. Since a seminal paper reporting immunoglobulin expression in transgenic plants was published in 1989, there have been many technological advances in plant expression systems to the present time where production of proteins in leaf tissues of nonfood crops such as Nicotiana species is considered a viable alternative. In particular, transient expression systems derived from recombinant plant viral vectors offer opportunities for rapid expression screening, construct optimization, and expression scale-up. Extraction of recombinant proteins from Nicotiana leaf tissues can be achieved by collection of secreted protein fractions, or from a total protein extract after grinding the leaves with buffer. After separation from solids, the major purification challenge is contamination with elements of the photosynthetic complex, which can be solved by application of a variety of facile and proven strategies. In conclusion, the technologies required for safe, efficient, scalable manufacture of recombinant proteins in Nicotiana leaf tissues have matured to the point where several products have already been tested in phase I clinical trials and will soon be followed by a rich pipeline of recombinant vaccines, microbicides, and therapeutic proteins.

  6. Stormwater Attenuation by Green Roofs

    Science.gov (United States)

    Sims, A.; O'Carroll, D. M.; Robinson, C. E.; Smart, C. C.

    2014-12-01

    Innovative municipal stormwater management technologies are urgently required in urban centers. Inadequate stormwater management can lead to excessive flooding, channel erosion, decreased stream baseflows, and degraded water quality. A major source of urban stormwater is unused roof space. Green roofs can be used as a stormwater management tool to reduce roof generated stormwater and generally improve the quality of runoff. With recent legislation in some North American cities, including Toronto, requiring the installation of green roofs on large buildings, research on the effectiveness of green roofs for stormwater management is important. This study aims to assess the hydrologic response of an extensive sedum green roof in London, Ontario, with emphasis on the response to large precipitation events that stress municipal stormwater infrastructure. A green roof rapidly reaches field capacity during large storm events and can show significantly different behavior before and after field capacity. At field capacity a green roof has no capillary storage left for retention of stormwater, but may still be an effective tool to attenuate peak runoff rates by transport through the green roof substrate. The attenuation of green roofs after field capacity is linked to gravity storage, where gravity storage is the water that is temporarily stored and can drain freely over time after field capacity has been established. Stormwater attenuation of a modular experimental green roof is determined from water balance calculations at 1-minute intervals. Data is used to evaluate green roof attenuation and the impact of field capacity on peak flow rates and gravity storage. In addition, a numerical model is used to simulate event based stormwater attenuation. This model is based off of the Richards equation and supporting theory of multiphase flow through porous media.

  7. Recombinant human thrombopoietin in myelosuppressive chemotherapy.

    Science.gov (United States)

    Vadhan-Raj, S

    2001-07-01

    Recombinant human thrombopoietin (rhTPO) is a full-length glycosylated molecule that has been under evaluation in the setting of chemotherapy-induced myelosuppression. It has been shown to be a potent stimulator of platelet production in cancer patients when administered prior to chemotherapy. The peak platelet response to a single dose of rhTPO is observed around day 12, and is accompanied by a significant increase in the number of mature megakaryocytes in bone marrow. Consistent with this biologic effect, rhTPO administered postchemotherapy has been shown to be effective in attenuating severe thrombocytopenia induced by carboplatin, which produces a late platelet nadir. Early clinical experience with a regimen that produces an early nadir, however, such as AI (doxorubicin [Adriamycin] and ifosfamide [Ifex]), suggests that administration of rhTPO both prior to and following chemotherapy might be important to reduce thrombocytopenia severity. Treatment with rhTPO in these clinical trials has been well tolerated with a favorable safety profile. Randomized clinical trials have been initiated to determine further the importance of schedule in the prevention and treatment of severe thrombocytopenia in cancer patients.

  8. Intracellular processing and presentation of T cell epitopes, expressed by recombinant Escherichia coli and Salmonella typhimurium, to human T cells

    NARCIS (Netherlands)

    G.M.G.M. Verjans (George); C.M. Janssen (Riny); F.G.C.M. Uytdehaag (Fons); C.E.M. van Doornik (C. E M); J. Tommassen (Jan)

    1995-01-01

    textabstractVaccines based on recombinant attenuated bacteria represent a potentially safe and effective immunization strategy. A carrier system was developed to analyze in vitro whether foreign T cell epitopes, inserted in the outer membrane protein PhoE of Escherichia coli and expressed by recombi

  9. Evaluation of the infection and transmission of wild type and recombinant strains of Newcastle disease virus in Japanese Quail

    Science.gov (United States)

    Newcastle disease virus (NDV) causes a range of clinical disease ranging from asymptomatic infection to severe disease with high mortality. Vaccination for NDV is practiced almost worldwide in commercial chickens. Attenuated live vaccines are most commonly used, with recombinant vaccines becoming ...

  10. 重组人红细胞生成素通过上调核因子-κB p65减少同型半胱氨酸诱导的培养内皮细胞凋亡%Recombinant human erythropoietin attenuates homocysteine-induced apoptosis in cultured endothelial cells via upregulating nuclear factor-κB

    Institute of Scientific and Technical Information of China (English)

    李敏子; 刘振华; 杨卫红

    2013-01-01

    Objective To investigate the effect of erythropoietin (EPO) on vascular endothelial cell apoptosis induced by homocysteine (Hcy) and the role of nuclear factor-κB (NF-κB) p65.Methods Human umbilical vein endothelial cells (HUVECs) were divided into normal control,Hcy treatment,EPO pretreatment,and simple EPO groups.The cell viability was detected by the methylthiazolyl tetrazolium (MTT) assay,the apoptosis rate was measured by flow cytometry,and the expression of NF-κB p65 was tested by Western blot.Results The apoptosis rates in the groups of the normal control,Hcy treatment,EPO pretreatment and simple EPO (all n =3) were 2.23 ± 0.4%,12.8 ± 1.2%,3.2 ± 0.5% and 2.18 ± 0.6%,respectively (F =1 105.630,P =0.000).The apoptosis rate in the Hcy treatment goup was significantly higher than that in the normal control group (P =0.000) ; there was no significant differences between the simple EPO group and the normal control group (P =0.616); the apoptosis rates in the groups of EPO pretreatment (P =0.000) and simple EPO (P =0.000) were significantly lower than that in the Hcy treatment group.Western blot analysis showed that the normal control group almost did not express NF-κB p65.The expression of NF-κB p65 in the groups of Hcy treatment,simple EPO and EPO pretreatment (all n =3) were 66.1 ± 7.3,1 046.1 ± 71.3 and 1 362.4 ± 25.3,respectively.There were significant differences among the 3 groups (F =1 310.954,P =0.000).The expression of NF-κB p65 in the groups of EPO pretreatment (P =0.000) and simple EPO (P=0.000) were significantly higher than that in the HCY group.The expression of NF-κB p65 in the EPO pretreatment group was significantly higher than that in the simple EPO group (P =0.007).Conelusions EPO may attenuate Hcy-induced endothelial cell apoptosis via upregulating the expression of NF-κB p65.%目的 探讨红细胞生成素(erythropoietin,EPO)对同型半胱氨酸(homocysteine,Hcy)诱导的血管内皮细胞凋亡的

  11. RECOMBINANT HORSERADISH PEROXIDASE FOR ANALYTICAL APPLICATIONS

    Directory of Open Access Journals (Sweden)

    А.M. Egorov

    2012-08-01

    Full Text Available The article deals with prospects of using recombinant horseradish peroxidase in analytical biochemistry and biotechnology. Problems of recombinant horseradish peroxidase cloning in different expression systems, possible approaches to their solution, advantages of recombinant recombinant horseradish peroxidase and recombinant horseradish peroxidase-fusion proteins for immunoassays are considered. Possibility for development of mediatorless bienzyme biosensor for peroxide and metabolites, yielding hydrogen peroxide during their transformations, based on co-adsorption of recombinant horseradish peroxidase and the appropriate oxidase was demonstrated. The possibility to produce a fully active recombinant conjugate of recombinant horseradish peroxidase with human heart-type fatty acid binding protein, which may be used in competitive immunoassay for clinical diagnosis of acute myocardial infarction, and recombinant conjugates (N- and C-terminus of recombinant horseradish peroxidase with Fab-fragments of the antibody against atrazine, which may be applied for atrazine pesticides detection, are demonstra ted for the first time.

  12. Ferrite attenuator modulation improves antenna performance

    Science.gov (United States)

    Hooks, J. C.; Larson, S. G.; Shorkley, F. H.; Williams, B. T.

    1970-01-01

    Ferrite attenuator inserted into appropriate waveguide reduces the gain of the antenna element which is causing interference. Modulating the ferrite attenuator to change the antenna gain at the receive frequency permits ground tracking until the antenna is no longer needed.

  13. Recombinant human erythropoietin attenuates pulmonary inflammatory in newborn rats with chronical hyperoxia-induced bronchopulmonary dysplasia%重组人促红细胞生成素减轻慢性高体积分数氧致支气管肺发育不良新生大鼠的炎性反应

    Institute of Scientific and Technical Information of China (English)

    耿琳琳; 吕伟; 宋靖荣

    2015-01-01

    Objective To investigate anti-inflammatory effect of recombinant human erythropoietin(rhEPO) on bronchopulmonary dysplasia in newborn rats exposed to hyperoxia.Methods Ninety-six Wistar newborn rats were randomly divided into 4 groups after birth:room air-exposed control group,room air-exposed rhEPO treated group,hyperoxia-exposed group,and the hyperoxia-exposed rhEPO treated group.The last two groups were exposed to oxygen,FiO2 =850 mL/L,room air-exposed rhEPO treated and hyperoxia-exposed rhEPO treated group received rhEPO 2 400 IU/kg subcutaneously at birth,30 minutes' before oxygen exposure and 2 d after birth.The isodose of 9 g/L saline was given in the same way in room air-exposed controls and hyperoxia-exposed pups.Rats from each group were sacrificed on day 3,7 and 10.Lung histology was observed under microscope,and mRNA expression of monocyte chemoattractant protein-1 (MCP-1) and cytokine-induced neutrophil hemoattractant-1 (CINC-1) were determined with reverse transcriotion-polymerase chain reaction(RT-PCR).Results Under microscope,in the hyperoxia-exposed group,inflammatory cell influx was detected in the lungs on the 3rd day and there was marked neutrophlic infiltrate on the 7th day.Alveolar enlargement and fibrosis were evident on the 10th day.At the same time,the histopathological changes were improved greatly in the lungs of hyperoxia-exposed rhEPO treated pups compared with the hyperoxia-exposed pups.MCP-1 and CINC-1 mRNA expression increased in hyperoxia-exposed pups,compared with room air-exposed controls especially on the 7th day [(0.94 ± 0.45) vs (0.21 ± 0.03),P < 0.001 ; (1.26 ± 0.29) vs (0.26 ± 0.06),P < 0.001].MCP-1 and CINC-1 mRNA expression were greatly depressed in the hyperoxia-exposed rhEPO treated pups compared with the hyperoxia-exposed pups especially on the 7th day.[(0.65 ± 0.07) vs (0.94 ± 0.45),P<0.05;(0.83±0.07) vs (1.26±0.29),P<0.05].Conclusions The therapy of rhEPO (2 400 IU/kg) therapy can reduce lung

  14. Conservation of recombination hotspots in yeast

    OpenAIRE

    Tsai, Isheng J.; Burt, Austin; Koufopanou, Vassiliki

    2010-01-01

    Meiotic recombination does not occur randomly along a chromosome, but instead tends to be concentrated in small regions, known as “recombination hotspots.” Recombination hotspots are thought to be short-lived in evolutionary time due to their self-destructive nature, as gene conversion favors recombination-suppressing alleles over recombination-promoting alleles during double-strand repair. Consistent with this expectation, hotspots in humans are highly dynamic, with little correspondence in ...

  15. Recombination at the DNA level. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    1984-01-01

    Abstracts of papers in the following areas are presented: (1) chromosome mechanics; (2) yeast systems; (3) mammalian homologous recombination; (4) transposons; (5) Mu; (6) plant transposons/T4 recombination; (7) topoisomerase, resolvase, and gyrase; (8) Escherichia coli general recombination; (9) recA; (10) repair; (11) eucaryotic enzymes; (12) integration and excision of bacteriophage; (13) site-specific recombination; and (14) recombination in vitro. (ACR)

  16. ENHANCEMENTS TO NATURAL ATTENUATION: SELECTED CASE STUDIES

    Energy Technology Data Exchange (ETDEWEB)

    Vangelas, K; W. H. Albright, W; E. S. Becvar, E; C. H. Benson, C; T. O. Early, T; E. Hood, E; P. M. Jardine, P; M. Lorah, M; E. Majche, E; D. Major, D; W. J. Waugh, W; G. Wein, G; O. R. West, O

    2007-05-15

    In 2003 the US Department of Energy (DOE) embarked on a project to explore an innovative approach to remediation of subsurface contaminant plumes that focused on introducing mechanisms for augmenting natural attenuation to achieve site closure. Termed enhanced attenuation (EA), this approach has drawn its inspiration from the concept of monitored natural attenuation (MNA).

  17. Recombinant vaccines and the development of new vaccine strategies

    Directory of Open Access Journals (Sweden)

    I.P. Nascimento

    2012-12-01

    Full Text Available Vaccines were initially developed on an empirical basis, relying mostly on attenuation or inactivation of pathogens. Advances in immunology, molecular biology, biochemistry, genomics, and proteomics have added new perspectives to the vaccinology field. The use of recombinant proteins allows the targeting of immune responses focused against few protective antigens. There are a variety of expression systems with different advantages, allowing the production of large quantities of proteins depending on the required characteristics. Live recombinant bacteria or viral vectors effectively stimulate the immune system as in natural infections and have intrinsic adjuvant properties. DNA vaccines, which consist of non-replicating plasmids, can induce strong long-term cellular immune responses. Prime-boost strategies combine different antigen delivery systems to broaden the immune response. In general, all of these strategies have shown advantages and disadvantages, and their use will depend on the knowledge of the mechanisms of infection of the target pathogen and of the immune response required for protection. In this review, we discuss some of the major breakthroughs that have been achieved using recombinant vaccine technologies, as well as new approaches and strategies for vaccine development, including potential shortcomings and risks.

  18. Recombinant vaccines and the development of new vaccine strategies.

    Science.gov (United States)

    Nascimento, I P; Leite, L C C

    2012-12-01

    Vaccines were initially developed on an empirical basis, relying mostly on attenuation or inactivation of pathogens. Advances in immunology, molecular biology, biochemistry, genomics, and proteomics have added new perspectives to the vaccinology field. The use of recombinant proteins allows the targeting of immune responses focused against few protective antigens. There are a variety of expression systems with different advantages, allowing the production of large quantities of proteins depending on the required characteristics. Live recombinant bacteria or viral vectors effectively stimulate the immune system as in natural infections and have intrinsic adjuvant properties. DNA vaccines, which consist of non-replicating plasmids, can induce strong long-term cellular immune responses. Prime-boost strategies combine different antigen delivery systems to broaden the immune response. In general, all of these strategies have shown advantages and disadvantages, and their use will depend on the knowledge of the mechanisms of infection of the target pathogen and of the immune response required for protection. In this review, we discuss some of the major breakthroughs that have been achieved using recombinant vaccine technologies, as well as new approaches and strategies for vaccine development, including potential shortcomings and risks.

  19. Recombinant vaccines and the development of new vaccine strategies

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, I.P.; Leite, L.C.C. [Centro de Biotecnologia, Instituto Butantan, São Paulo, SP (Brazil)

    2012-09-07

    Vaccines were initially developed on an empirical basis, relying mostly on attenuation or inactivation of pathogens. Advances in immunology, molecular biology, biochemistry, genomics, and proteomics have added new perspectives to the vaccinology field. The use of recombinant proteins allows the targeting of immune responses focused against few protective antigens. There are a variety of expression systems with different advantages, allowing the production of large quantities of proteins depending on the required characteristics. Live recombinant bacteria or viral vectors effectively stimulate the immune system as in natural infections and have intrinsic adjuvant properties. DNA vaccines, which consist of non-replicating plasmids, can induce strong long-term cellular immune responses. Prime-boost strategies combine different antigen delivery systems to broaden the immune response. In general, all of these strategies have shown advantages and disadvantages, and their use will depend on the knowledge of the mechanisms of infection of the target pathogen and of the immune response required for protection. In this review, we discuss some of the major breakthroughs that have been achieved using recombinant vaccine technologies, as well as new approaches and strategies for vaccine development, including potential shortcomings and risks.

  20. Chlorine signal attenuation in concrete.

    Science.gov (United States)

    Naqvi, A A; Maslehuddin, M; ur-Rehman, Khateeb; Al-Amoudi, O S B

    2015-11-01

    The intensity of prompt gamma-ray was measured at various depths from chlorine-contaminated silica fume (SF) concrete slab concrete specimens using portable neutron generator-based prompt gamma-ray setup. The intensity of 6.11MeV chloride gamma-rays was measured from the chloride contaminated slab at distance of 15.25, 20.25, 25.25, 30.25 and 35.25cm from neutron target in a SF cement concrete slab specimens. Due to attenuation of thermal neutron flux and emitted gamma-ray intensity in SF cement concrete at various depths, the measured intensity of chlorine gamma-rays decreases non-linearly with increasing depth in concrete. A good agreement was noted between the experimental results and the results of Monte Carlo simulation. This study has provided useful experimental data for evaluating the chloride contamination in the SF concrete utilizing gamma-ray attenuation method.

  1. Recombinant allergens for pollen immunotherapy.

    Science.gov (United States)

    Wallner, Michael; Pichler, Ulrike; Ferreira, Fatima

    2013-12-01

    Specific immunotherapy (IT) represents the only potentially curative therapeutic intervention of allergic diseases capable of suppressing allergy-associated symptoms not only during treatment, but also after its cessation. Presently, IT is performed with allergen extracts, which represent a heterogeneous mixture of allergenic, as well as nonallergenic, compounds of a given allergen source. To overcome many of the problems associated with extract-based IT, strategies based on the use of recombinant allergens or derivatives thereof have been developed. This review focuses on recombinant technologies to produce allergy therapeuticals, especially for allergies caused by tree, grass and weed pollen, as they are among the most prevalent allergic disorders affecting the population of industrialized societies. The reduction of IgE-binding of recombinant allergen derivatives appears to be mandatory to increase the safety profile of vaccine candidates. Moreover, increased immunogenicity is expected to reduce the dosage regimes of the presently cumbersome treatment. In this regard, it has been convincingly demonstrated in animal models that hypoallergenic molecules can be engineered to harbor inherent antiallergenic immunologic properties. Thus, strategies to modulate the allergenic and immunogenic properties of recombinant allergens will be discussed in detail. In recent years, several successful clinical studies using recombinant wild-type or hypoallergens as active ingredients have been published and, currently, novel treatment forms with higher safety and efficacy profiles are under investigation in clinical trials. These recent developments are summarized and discussed.

  2. Mechanisms of geometrical seismic attenuation

    Directory of Open Access Journals (Sweden)

    Igor B. Morozov

    2011-07-01

    Full Text Available In several recent reports, we have explained the frequency dependence of the apparent seismic quality-factor (Q observed in many studies according to the effects of geometrical attenuation, which was defined as the zero-frequency limit of the temporal attenuation coefficient. In particular, geometrical attenuation was found to be positive for most waves traveling within the lithosphere. Here, we present three theoretical models that illustrate the origin of this geometrical attenuation, and we investigate the causes of its preferential positive values. In addition, we discuss the physical basis and limitations of both the conventional and new attenuation models. For waves in media with slowly varying properties, geometrical attenuation is caused by variations in the wavefront curvature, which can be both positive (for defocusing and negative (for focusing. In media with velocity/density contrasts, incoherent reflectivity leads to geometrical-attenuation coefficients which are proportional to the mean squared reflectivity and are always positive. For «coherent» reflectivity, the geometrical attenuation is approximately zero, and the attenuation process can be described according to the concept of «scattering Q». However, the true meaning of this parameter is in describing the mean reflectivity within the medium, and not that of the traditional resonator quality factor known in mechanics. The general conclusion from these models is that non-zero and often positive levels of geometrical attenuation are common in realistic, heterogeneous media, both observationally and theoretically. When transformed into the conventional Q-factor form, this positive geometrical attenuation leads to Q values that quickly increase with frequency. These predictions show that the positive frequency-dependent Q observed in many datasets might represent artifacts of the transformations of the attenuation coefficients into Q.

  1. Cross-Protection against Marburg Virus Strains by Using a Live, Attenuated Recombinant Vaccine

    Science.gov (United States)

    2006-10-01

    Guttieri, B. R. Mothe, T. Larsen, L. E. Hensley, P. B. Jahrling, and H. Feldmann. 2005. Development of a new vaccine for the prevention of Lassa fever ...Manitoba, Canada Received 10 May 2006/Accepted 12 July 2006 Marburg virus (MARV) has been associated with sporadic episodes of hemorrhagic fever ...lineages within the Lake Victoria marburgvirus species of MARV. The original MARV isolates from the 1967 episodes in Marburg, Germany (Popp and Ratayczak

  2. Attenuation map reconstruction from TOF PET data

    CERN Document Server

    Yang, Qingsong; Wang, Ge

    2013-01-01

    To reconstruct a radioactive tracer distribution with positron emission tomography (PET), the background attenuation correction is needed to eliminate image artifacts. Recent research shows that time-of-flight (TOF) PET data determine the attenuation sinogram up to a constant, and its gradient can be computed using an analytic algorithm. In this paper, we study a direct estimation of the sinogram only from TOF PET data. First, the gradient of the attenuation sinogram is estimated using the aforementioned algorithm. Then, a relationship is established to link the differential attenuation sinogram and the underlying attenuation background. Finally, an iterative algorithm is designed to determine the attenuation sinogram accurately and stably. A 2D numerical simulation study is conducted to verify the correctness of our proposed approach.

  3. Extended recombinant bacterial ghost system.

    Science.gov (United States)

    Lubitz, W; Witte, A; Eko, F O; Kamal, M; Jechlinger, W; Brand, E; Marchart, J; Haidinger, W; Huter, V; Felnerova, D; Stralis-Alves, N; Lechleitner, S; Melzer, H; Szostak, M P; Resch, S; Mader, H; Kuen, B; Mayr, B; Mayrhofer, P; Geretschläger, R; Haslberger, A; Hensel, A

    1999-08-20

    Controlled expression of cloned PhiX174 gene E in Gram-negative bacteria results in lysis of the bacteria by formation of an E-specific transmembrane tunnel structure built through the cell envelope complex. Bacterial ghosts from a variety of bacteria are used as non-living candidate vaccines. In the recombinant ghost system, foreign proteins are attached on the inside of the inner membrane as fusions with specific anchor sequences. Ghosts have a sealed periplasmic space and the export of proteins into this space vastly extends the capacity of ghosts or recombinant ghosts to function as carriers of foreign antigens. In addition, S-layer proteins forming shell-like self assembly structures can be expressed in candidate vaccine strains prior to E-mediated lysis. Such recombinant S-layer proteins carrying foreign epitopes further extend the possibilities of ghosts as carriers of foreign epitopes. As ghosts have inherent adjuvant properties, they can be used as adjuvants in combination with subunit vaccines. Subunits or other ligands can also be coupled to matrixes like dextran which are used to fill the internal lumen of ghosts. Oral, aerogenic or parenteral immunization of experimental animals with recombinant ghosts induced specific humoral and cellular immune responses against bacterial and target components including protective mucosal immunity. The most relevant advantage of recombinant bacterial ghosts as immunogens is that no inactivation procedures that denature relevant immunogenic determinants are employed in this production. This fact explains the superior quality of ghosts when compared to other inactivated vaccines. The endotoxic component of the outer membrane does not limit the use of ghosts as vaccine candidates but triggers the release of several potent immunoregulatory cytokines. As carriers, there is no limitation in the size of foreign antigens that can be inserted in the membrane and the capacity of all spaces including the membranes, peri

  4. Optimal ultrasonic array focusing in attenuative media.

    Science.gov (United States)

    Ganguli, A; Gao, R X; Liang, K; Jundt, J

    2011-12-01

    This paper presents a parametric study on the efficiency of ultrasound focusing in an attenuative medium, using phased arrays. Specifically, an analytical model of ultrasound wave focusing in a homogeneous, isotropic and attenuative fluid with point sources is presented. Calculations based on the model have shown that in an attenuative medium, an optimum frequency exists for the best focusing performance for a particular size of aperture and focal distance. The effect of different f numbers on the focusing performance in the attenuative medium is further investigated. The information obtained from the analytical model provides insights into the design and installation of a phased transducer array for energy efficient wave focusing.

  5. Wideband, 50 dB Attenuation Range Liquid Crystal Based Variable Optical Attenuator

    Institute of Scientific and Technical Information of China (English)

    J.J.; Pan; Henry; He; Eric; Zhang

    2003-01-01

    A compact variable optical attenuator, covering C and L bands with over 50 dB attenuation range, is realized using a single liquid crystal cell with a tilted fused silica coating compensating the cell's small residual birefringence.

  6. Construction of two Listeria ivanovii attenuated strains expressing Mycobacterium tuberculosis antigens for TB vaccine purposes.

    Science.gov (United States)

    Lin, Qingqing; Zhou, Mengying; Xu, Zongkai; Khanniche, Asma; Shen, Hao; Wang, Chuan

    2015-02-20

    Bacillus Calmette-Guerin (BCG) has failed in complete control of tuberculosis (TB), thus, novel tuberculosis vaccines are urgently needed. We have constructed several TB vaccine candidates, which are characterized by the use of Listeria ivanovii (LI) strain as an antigen delivery vector. Two L. ivanovii attenuated recombinant strains L. ivanovii△actAplcB-Rv0129c and L. ivanovii△actAplcB-Rv3875 were successfully screened. Results from genome PCR and sequencing showed that the Mycobacterium tuberculosis antigen gene cassette coding for Ag85C or ESAT-6 protein respectively had been integrated into LI genome downstream of mpl gene. Western blot confirmed the secretion of Ag85C or ESAT-6 protein from the recombinant LI strains. These two recombinant strains showed similar growth curves as wide type strain in vitro. In vivo, they transiently propagated in mice spleen and liver, and induced specific CD8(+) IFN-γ secretion. Therefore, in this paper, two novel LI attenuated strains expressing specific TB antigens were successfully constructed. The promising growth characteristics in mice immune system and the capability of induction of IFN-γ secretion make them of potential interest for development of TB vaccines.

  7. Immunogenicity of transmissible gastroenteritis virus (TGEV) M gene delivered by attenuated Salmonella typhimurium in mice.

    Science.gov (United States)

    Qing, Ying; Liu, Jiawen; Huang, Xiaobo; Li, Yaqing; Zhang, Yudi; Chen, Jie; Wen, Xintian; Cao, Sanjie; Wen, Yiping; Wu, Rui; Yan, Qigui; Ma, Xiaoping

    2016-04-01

    Attenuated Salmonella typhimurium (S. typhimurium) was selected as a transgenic vehicle for the development of live mucosal vaccines against transmissible gastroenteritis virus (TGEV) based on the M gene. An approximate 1.0 kb DNA fragment, encoding for glycoprotein M, was amplified by RT-PCR and cloned into eukaryotic expression vector pVAX1. The recombinant plasmid pVAX-M was transformed by electroporation into attenuated S. typhimurium SL7207, and the expression and translation of the pVAX-M delivered by recombinant S. typhimurium SL7207 (pVAX-M) was detected both in vitro and in vivo. BALB/c mice were inoculated orally with SL7207 (pVAX-M) at different dosages to evaluate safety of the vaccines. The bacterium was safe to mice at a dosage of 2 × 10(9) CFU, almost eliminated from the spleen and liver at week 4 post-immunization and eventually cleared at week 6. Mice immunized with 1 × 10(9) CFU of SL7207 (pVAX-M) elicited specific anti-TGEV local mucosal and humoral responses including levels of IgA, IgG, IL-4, and IFN-γ as measured by indirect ELISA assay. Moreover, the control groups (pVAX group, PBS group) maintained at a normal level during week 4-8 post-immunization. The results indicated that attenuated S. typhimurium could be used as a delivery vector for oral immunization of TGEV M gene vaccine.

  8. Recombinant protein production in bacterial hosts.

    Science.gov (United States)

    Overton, Tim W

    2014-05-01

    The production of recombinant proteins is crucial for both the development of new protein drugs and the structural determination of drug targets. As such, recombinant protein production has a major role in drug development. Bacterial hosts are commonly used for the production of recombinant proteins, accounting for approximately 30% of current biopharmaceuticals on the market. In this review, I introduce fundamental concepts in recombinant protein production in bacteria, from drug development to production scales. Recombinant protein production processes can often fail, but how can this failure be minimised to rapidly deliver maximum yields of high-quality protein and so accelerate drug discovery?

  9. Homologous recombination in Leishmania enriettii.

    OpenAIRE

    1991-01-01

    We have used derivatives of the recently developed stable transfection vector pALT-Neo to formally demonstrate that Leishmania enriettii contains the enzymatic machinery necessary for homologous recombination. This observation has implications for gene regulation, gene amplification, genetic diversity, and the maintenance of tandemly repeated gene families in the Leishmania genome as well as in closely related organisms, including Trypanosoma brucei. Two plasmids containing nonoverlapping del...

  10. Recombinant Toxins for Cancer Treatment

    Science.gov (United States)

    Pastan, Ira; Fitzgerald, David

    1991-11-01

    Recombinant toxins target cell surface receptors and antigens on tumor cells. They kill by mechanisms different from conventional chemotherapy, so that cross resistance to conventional chemotherapeutic agents should not be a problem. Furthermore, they are not mutagens and should not induce secondary malignancies or accelerate progression of benign malignancies. They can be mass-produced cheaply in bacteria as homogeneous proteins. Either growth factor-toxin fusions or antibody-toxin fusions can be chosen, depending on the cellular target.

  11. Novel applications of recombinant erythropoietin.

    Science.gov (United States)

    Sharples, Edward J; Thiemermann, Christoph; Yaqoob, Magdi M

    2006-04-01

    Recombinant erythropoietin (EPO) was introduced into clinical practice after the identification of EPO as the major haemopoietic growth factor determining survival and maturation of erythroid precursors. Advances in our understanding of the novel sites of action of EPO in the vasculature, brain, heart and kidney have opened new avenues of therapeutic potential for EPO, and have led to an increased understanding of the biological roles of EPO and its mechanisms of cell protection.

  12. Recombinant house dust mite allergens

    OpenAIRE

    2013-01-01

    House dust mites (HDM) are a globally important source of allergen responsible for the sensitization of more than 50% of allergic patients. Specific immunotherapy with HDM extracts is effective but allergen extracts cannot be fully standardized and severe side-effects can occur during the protracted course of treatment. The introduction of molecular biological techniques into allergy research allowed the indentification of more than 20 groups of HDM allergens. Recombinant HDM allergens can be...

  13. Ultrasonic attenuation in cuprate superconductors

    Indian Academy of Sciences (India)

    T Gupta; D M Gaitonde

    2002-05-01

    We calculate the longitudinal ultrasonic attenuation rate (UAR) in clean d-wave superconductors in the Meissner and the mixed phases. In the Meissner phase we calculate the contribution of previously ignored processes involving the excitation of a pair of quasi-holes or quasi-particles. There is a contribution ∝ in the regime B ≪ F ≪ 0 and a contribution ∝ 1/ in the regime F ≪ B ≪ 0. We find that these contributions to the UAR are large and cannot be ignored. In the mixed phase, using a semi-classical description, we calculate the electronic quasi-particle contribution to the UAR which at very low , has a independent term proportional to $\\sqrt{H}$.

  14. Workshop on Radio Recombination Lines

    CERN Document Server

    1980-01-01

    Since their first detection 15 years ago, radio recombination lines from several elements have been observed in a wide variety of objects including HII regions, planetary nebulae, molecular clouds, the diffuse interstellar medium, and recently, other galaxies. The observations span almost the entire range from 0.1 to 100 GHz, and employ both single­ djsh and aperture synthesis techniques. The theory of radio recombination lines has also advanced strongly, to the point where it is perhaps one of the best-understood in astro­ physics. In a parallel development, it has become possible over the last decade to study these same highly-excited atoms in the laboratory; this work provides further confirmation of the theoretical framework. However there has been continuing controversy over the astrophysical interpre­ tation of radio recombination line observations, especially regarding the role of stimulated emission. A workshop was held in Ottawa on 24-25 August, 1979, bringing together many of the active scientist...

  15. DSM-5: ATTENUATED PSYCHOSIS SYNDROME?

    Directory of Open Access Journals (Sweden)

    Eduardo Fonseca-Pedrero

    2013-09-01

    Full Text Available Psychotic syndrome includes several devastating mental disorders characterized by a rupture of higher mental functions. The signs and symptoms of psychosis begin in adolescence or early adulthood and usually begin gradually and progress over time. Attenuated psychosis syndrome is a new DSM-5 diagnostic proposal which deals with identifying people at high-risk mental state (ARMS/UHR which may be a predictor of conversion to psychosis. The potential benefit would be that if psychotic disorder is treated more effectively in its early stages, it could produce a lasting beneficial effect that probably could not be achieved with later intervention. This syndrome has generated intense discussion in specialized scientific and professional forums, crisscrossing arguments in favor and against its inclusion. HRMS is preferentially evaluated in the adolescent or young adult population. HRMS evolution is associated with a higher rate of transition toward nonaffective psychosis, although it can evolve toward other mental disorders, remain stable or remit over time. Empirical evidence shows that early intervention seems to have a certain beneficial effect, although for now the results are still insufficient and contradictory. The lack of specificity of symptoms in predicting psychosis, presence of certain limitations (e.g., stigmatization, results found in early interventions and lack of empirical evidence, have led to include the attenuated psychosis syndrome in the DSM-5 Appendix III. The main benefits and limitations of including this supposed category, possible lessons learned from this type of study and future lines of action are discussed in the light of these findings.

  16. Nondisjunction of chromosome 15: Origin and recombination

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, W.P.; Bernasconi, F.; Schinzel, A.A.; Mutirangura, A.; Ledbetter, D.H. (Baylor College of Medicine, Houston, TX (United States)); Langlois, S. (Univ. of Britisch Columbia, Vancouver (Canada)); Morris, M.A.; Malcolm, S.

    1993-09-01

    Thirty-two cases of uniparental disomy (UPD), ascertained from Prader-Willi syndrome patients (N=27) and Angelman syndrome patients (N-5), are used to investigate the pattern of recombination associated with nondisjunction of chromosome 15. In addition, the meiotic stage of nondisjunction is inferred by using markers mapping near the centromere. Two basic approaches to the analysis of recombination in specific pairwise intervals along the chromosome. This method shows a significant reduction in recombination for two of five intervals examined. Second, the observed frequency of each recombinant class (i.e., zero, one, two, three, or more observable crossovers) is compared with expected values. This is useful for testing whether the reduction in recombination can be attributed solely to a proportion of cases with no recombination at all (because of asynapsis), with the remaining groups showing normal recombination (or even excess recombination), or whether recombination is uniformly reduced. Analysis of maternal UPD(15) data shows a slight reduction in the multiple-recombinant classes, with a corresponding increase in both the zero- and one-recombinant classes over expected values. The majority, more than 82%, of the extra chromosomes in maternal UPD(15) cases are due to meiotic I nondisjunction events. In contrast, more paternal UPD(15) cases so far examined appear to have a postzygotic origin of the extra paternal chromosome. 33 refs., 1 fig., 7 tabs.

  17. Consequences of recombination on traditional phylogenetic analysis

    DEFF Research Database (Denmark)

    Schierup, M H; Hein, J

    2000-01-01

    We investigate the shape of a phylogenetic tree reconstructed from sequences evolving under the coalescent with recombination. The motivation is that evolutionary inferences are often made from phylogenetic trees reconstructed from population data even though recombination may well occur (mtDNA...... or viral sequences) or does occur (nuclear sequences). We investigate the size and direction of biases when a single tree is reconstructed ignoring recombination. Standard software (PHYLIP) was used to construct the best phylogenetic tree from sequences simulated under the coalescent with recombination....... With recombination present, the length of terminal branches and the total branch length are larger, and the time to the most recent common ancestor smaller, than for a tree reconstructed from sequences evolving with no recombination. The effects are pronounced even for small levels of recombination that may...

  18. Attenuation characteristics of a light attenuator combined by polarizers with different extinction ratios

    Institute of Scientific and Technical Information of China (English)

    Huang Chong; Deng Peng; Zhao Shuang; Chen Hai-Qing

    2011-01-01

    This paper deals with a systematical analysis and an algorithm of attenuation characteristics of a light attenuator combined by n pieces of polarizers(n-LACP)whose extinction ratios are different from each other.The attenuation ratio expression of a two-LACP is deduced. We find that the monotonic attenuation interval depends on the first polarizer and that the attenuation range depends on the second one.For the three-LACP,a method for obtaining a monotonic attenuation interval is proposed.Moreover,the attenuation ratio expression is demonstrated.Analysis and experiment show that when the initial status of the three-LACP is at the maximum output,if the second or third polarizer rotates alone,the minimum attenuation ratios can reach K2-1and K3-1,respectively,and if the first polarizer rotates,a minimum attenuation ratio of K2-1K3-1can be obtained(K1,K2 and K3 represent the extinction ratios of the three polarizers in turn).Furthermore,the attenuation ratio expression of n-LACP and the relevant attenuation characteristics are proposed.The minimum attenuation ratio of an n-LACP is(K2K3...Kn)-1.

  19. The recombinant globular head domain of the measles virus hemagglutinin protein as a subunit vaccine against measles.

    Science.gov (United States)

    Lobanova, Liubov M; Eng, Nelson F; Satkunarajah, Malathy; Mutwiri, George K; Rini, James M; Zakhartchouk, Alexander N

    2012-04-26

    Despite the availability of live attenuated measles virus (MV) vaccines, a large number of measles-associated deaths occur among infants in developing countries. The development of a measles subunit vaccine may circumvent the limitations associated with the current live attenuated vaccines and eventually contribute to global measles eradication. Therefore, the goal of this study was to test the feasibility of producing the recombinant globular head domain of the MV hemagglutinin (H) protein by stably transfected human cells and to examine the ability of this recombinant protein to elicit MV-specific immune responses. The recombinant protein was purified from the culture supernatant of stably transfected HEK293T cells secreting a tagged version of the protein. Two subcutaneous immunizations with the purified recombinant protein alone resulted in the production of MV-specific serum IgG and neutralizing antibodies in mice. Formulation of the protein with adjuvants (polyphosphazene or alum) further enhanced the humoral immune response and in addition resulted in the induction of cell-mediated immunity as measured by the production of MV H-specific interferon gamma (IFN-γ) and interleukin 5 (IL-5) by in vitro re-stimulated splenocytes. Furthermore, the inclusion of polyphosphazene into the vaccine formulation induced a mixed Th1/Th2-type immune response. In addition, the purified recombinant protein retained its immunogenicity even after storage at 37°C for 2 weeks.

  20. Mechanistic features of recombination in HIV.

    Science.gov (United States)

    Galetto, Román; Negroni, Matteo

    2005-01-01

    The importance of recombination in retroviral evolution has been acknowledged for several decades. Consequently, after the identification of HIV as the etiological agent of AIDS, it was suspected that recombination could also play a central role in the evolution of this virus. However, only recently, extensive epidemiologic studies of HIV infections worldwide have provided an estimate for the occurrence of recombination in vivo, unveiling recombination frequencies that dwarf those initially expected. Nowadays, recombination is regarded as an integral part of the infectious cycle of this retrovirus, which impacts on diagnosis and treatment of infections, especially when genetically distant viruses have been at the origin of the recombinant forms. Retroviral recombination is observed when two genetically divergent genomic RNA molecules are present in the same viral particle, and arises during the reverse transcription step. This review focuses on the mechanisms that have been proposed to account for the occurrence of recombination in retroviruses, from the strand displacement model, according to which recombination occurs during second DNA strand synthesis; to the description of the factors responsible for copy-choice recombination during first DNA strand synthesis, such as the presence of breaks, pause sites, or secondary structures in the genomic RNA. Most of these models have been supported by experimental data obtained from in vitro reconstituted systems or from cell infection studies using academic model sequences. The situation in vivo is expected to be more complex, since several factors come into play when recombination involves relatively distant isolates, as in the case of inter-subtype recombination. At present, it is clear that further studies are needed in order to evaluate whether a prevailing mechanism exists for in vivo recombination, and these studies will also be essential for understanding how the underlying mechanisms of recombination contribute

  1. Inactivated Recombinant Rabies Viruses Displaying the Canine Distemper Virus Glycoproteins Induce Protective Immunity Against Both Pathogens.

    Science.gov (United States)

    Budaszewski, Renata da Fontoura; Hudacek, Andrew; Sawatsky, Bevan; Krämer, Beate; Xiangping, Yin; Schnell, Matthias J; von Messling, Veronika

    2017-02-01

    The development of multivalent vaccines is an attractive methodology for the simultaneous prevention of several infectious diseases in vulnerable populations. Canine distemper (CDV) and rabies (RABV) viruses both cause lethal disease in wild and domestic carnivores. While RABV vaccines are inactivated, the live-attenuated CDV vaccines retain residual virulence for highly susceptible wild life species. In the current study, we have developed recombinant bivalent vaccine candidates based on recombinant vaccine strain rabies virus particles, which concurrently display the protective CDV and RABV glycoprotein antigens. The recombinant viruses replicated to near wild type titers and the heterologous glycoproteins were efficiently expressed and incorporated in the viral particles. Immunization of ferrets with beta-propiolactone inactivated recombinant virus particles elicited protective RABV antibody titers, and animals immunized with a combination of CDV attachment and fusion protein-expressing recombinant viruses were protected from lethal CDV challenge. However, animals that were only immunized with a RABV expressing the attachment protein of the CDV vaccine strain Onderstepoort succumbed to the infection with a more recent wild type strain, indicating that immune responses to the more conserved fusion protein contribute to protection against heterologous CDV strains.

  2. Construction and characterization of recombinant Japanese encephalitis virus carrying brainspecific miRNA target sequences

    Directory of Open Access Journals (Sweden)

    Wen-yuan CAO

    2014-08-01

    Full Text Available Objective To construct the recombinant Japanese encephalitis virus ( JEV carrying brain-specific miRNA targeting sequences. Methods The target sequences of brain-specific miR-124 and miR-125 were introduced into the infectious cDNA clone of JEV to generate recombinant plasmids based on reverse genetics technology. The recombinant plasmids were linearized with Xho Ⅰ and served as templates of transcription with SP6 RNA polymerase to generate infectious viral RNA. The RNA transcripts were then transfected into BHK-21 cells, and the supernatant was obtained after incubated at 37℃, 5% CO2 for 3 days. The cytopathic changes of BHK-21 cells inoculated with the supernatant were observed after one passage. The rescued viruses carrying miRNA target sequences were validated by RT-PCR, standard plaque forming test on BHK-21 cells and growth curves analysis. Results Two recombinant viruses carrying miR-124 or miR-125 target sequence were rescued, respectively. The insertion of miRNA target sequences was confirmed by DNA sequencing. The rescued viruses yielded similar plaque morphology and replication efficiency compared with wild type JEV. Conclusion The recombinant JEV containing brain-specific miRNA target sequences can be obtained by reverse genetics technique, which could be used in further studies of miRNA-mediated tissue-specific attenuation mechanism of JEV. DOI: 10.11855/j.issn.0577-7402.2014.06.01

  3. Recombinant neural progenitor transplants in the spinal dorsal horn alleviate chronic central neuropathic pain.

    Science.gov (United States)

    Jergova, Stanislava; Gajavelli, Shyam; Pathak, Nirmal; Sagen, Jacqueline

    2016-04-01

    Neuropathic pain induced by spinal cord injury (SCI) is clinically challenging with inadequate long-term treatment options. Partial pain relief offered by pharmacologic treatment is often counterbalanced by adverse effects after prolonged use in chronic pain patients. Cell-based therapy for neuropathic pain using GABAergic neuronal progenitor cells (NPCs) has the potential to overcome untoward effects of systemic pharmacotherapy while enhancing analgesic potency due to local activation of GABAergic signaling in the spinal cord. However, multifactorial anomalies underlying chronic pain will likely require simultaneous targeting of multiple mechanisms. Here, we explore the analgesic potential of genetically modified rat embryonic GABAergic NPCs releasing a peptidergic NMDA receptor antagonist, Serine-histogranin (SHG), thus targeting both spinal hyperexcitability and reduced inhibitory processes. Recombinant NPCs were designed using either lentiviral or adeno-associated viral vectors (AAV2/8) encoding single and multimeric (6 copies of SHG) cDNA. Intraspinal injection of recombinant cells elicited enhanced analgesic effects compared with nonrecombinant NPCs in SCI-induced pain in rats. Moreover, potent and sustained antinociception was achieved, even after a 5-week postinjury delay, using recombinant multimeric NPCs. Intrathecal injection of SHG antibody attenuated analgesic effects of the recombinant grafts suggesting active participation of SHG in these antinociceptive effects. Immunoblots and immunocytochemical assays indicated ongoing recombinant peptide production and secretion in the grafted host spinal cords. These results support the potential for engineered NPCs grafted into the spinal dorsal horn to alleviate chronic neuropathic pain.

  4. DISTURBANCE ATTENUATION FOR UNCERTAIN NONLINEAR CASCADED SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    BI Weiping; MU Xiaowu; SUN Yuqiang

    2004-01-01

    In present paper, the disturbance attenuation problem of uncertain nonlinear cascaded systems is studied. Based on the adding one power integrator technique and recursive design, a feedback controller that solves the disturbance attenuation problem is constructed for uncertain nonlinear cascaded systems with internal stability.

  5. Light attenuation on Chlorella vulgaris cells

    Science.gov (United States)

    Krol, Tadeusz; Lotocka, Maria

    1993-12-01

    The laboratory measurements of spectrum of light attenuation on phytoplankton particles i.e. monoculture of unicellural green algae Chlorella vulgaris are presented. The measurements were carried out for alive culture and the cultures subjected to chemical (NaOH) or physical (ultrasounds) modification. The distinct changes in the light attenuation spectrum were a result of modification of the internal cell structures.

  6. Attenuation coefficients for water quality trading.

    Science.gov (United States)

    Keller, Arturo A; Chen, Xiaoli; Fox, Jessica; Fulda, Matt; Dorsey, Rebecca; Seapy, Briana; Glenday, Julia; Bray, Erin

    2014-06-17

    Water quality trading has been proposed as a cost-effective approach for reducing nutrient loads through credit generation from agricultural or point source reductions sold to buyers facing costly options. We present a systematic approach to determine attenuation coefficients and their uncertainty. Using a process-based model, we determine attenuation with safety margins at many watersheds for total nitrogen (TN) and total phosphorus (TP) loads as they transport from point of load reduction to the credit buyer. TN and TP in-stream attenuation generally increases with decreasing mean river flow; smaller rivers in the modeled region of the Ohio River Basin had TN attenuation factors per km, including safety margins, of 0.19-1.6%, medium rivers of 0.14-1.2%, large rivers of 0.13-1.1%, and very large rivers of 0.04-0.42%. Attenuation in ditches transporting nutrients from farms to receiving rivers is 0.4%/km for TN, while for TP attenuation in ditches can be up to 2%/km. A 95 percentile safety margin of 30-40% for TN and 6-10% for TP, applied to the attenuation per km factors, was determined from the in-stream sensitivity of load reductions to watershed model parameters. For perspective, over 50 km a 1% per km factor would result in 50% attenuation = 2:1 trading ratio.

  7. Ultrasound fields in an attenuating medium

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Gandhi,, D; O'Brien,, W.D., Jr.

    1993-01-01

    Ultrasound fields propagating in tissue will undergo changes in shape not only due to diffraction, but also due to the frequency dependent attenuation. Linear fields can be fairly well predicted for a non-attenuating medium like water by using the Tupholme-Stepanishen method for calculating...... the spatial impulse response, whereas the field cannot readily be found for an attenuating medium. In this paper we present a simulation program capable of calculating the field in a homogeneous attenuating medium. The program splits the aperture into rectangles and uses a far-field approximation for each...... of the rectangles and sums all contributions to arrive at the spatial impulse response for the aperture and field point. This approach makes it possible to model all transducer apertures, and the program can readily calculate the emitted, pulse-echo and continuous wave field. Attenuation is included by splitting...

  8. Bacteriophage recombination systems and biotechnical applications.

    Science.gov (United States)

    Nafissi, Nafiseh; Slavcev, Roderick

    2014-04-01

    Bacteriophage recombination systems have been widely used in biotechnology for modifying prokaryotic species, for creating transgenic animals and plants, and more recently, for human cell gene manipulation. In contrast to homologous recombination, which benefits from the endogenous recombination machinery of the cell, site-specific recombination requires an exogenous source of recombinase in mammalian cells. The mechanism of bacteriophage evolution and their coexistence with bacterial cells has become a point of interest ever since bacterial viruses' life cycles were first explored. Phage recombinases have already been exploited as valuable genetic tools and new phage enzymes, and their potential application to genetic engineering and genome manipulation, vectorology, and generation of new transgene delivery vectors, and cell therapy are attractive areas of research that continue to be investigated. The significance and role of phage recombination systems in biotechnology is reviewed in this paper, with specific focus on homologous and site-specific recombination conferred by the coli phages, λ, and N15, the integrase from the Streptomyces phage, ΦC31, the recombination system of phage P1, and the recently characterized recombination functions of Yersinia phage, PY54. Key steps of the molecular mechanisms involving phage recombination functions and their application to molecular engineering, our novel exploitations of the PY54-derived recombination system, and its application to the development of new DNA vectors are discussed.

  9. Current trends of HIV recombination worldwide

    Directory of Open Access Journals (Sweden)

    Katherine A. Lau

    2013-06-01

    Full Text Available One of the major characteristics of HIV-1 is its high genetic variability and extensive heterogeneity. This characteristic is due to its molecular traits, which in turn allows it to vary, recombine, and diversify at a high frequency. As such, it generates complex molecular forms, termed recombinants, which evade the human immune system and so survive. There is no sequence constraint to the recombination pattern as it appears to occur at inter-group (between groups M and O, as well as inter- and intra-subtype within group M. Rapid emergence and active global transmission of HIV-1 recombinants, known as circulating recombinant forms (CRFs and unique recombinant forms (URFs, requires urgent attention. To date, 55 CRFs have been reported around the world. The first CRF01_AE originated from Central Africa but spread widely in Asia. The most recent CRF; CRF55_01B is a recombinant form of CRF01_AE and subtype B, although its origin is yet to be publicly disclosed. HIV-1 recombination is an ongoing event and plays an indispensable role in HIV epidemics in different regions. Africa, Asia and South America are identified as recombination hot-spots. They are affected by continual emergence and co-circulation of newly emerging CRFs and URFs, which are now responsible for almost 20% of HIV-1 infections worldwide. Better understanding of recombinants is necessary to determine their biological and molecular attributes.

  10. Immunogenicity analysis following human immunodeficiency virus recombinant DNA and recombinant vaccinia virus Tian Tan prime-boost immunization.

    Science.gov (United States)

    Liu, Cunxia; Du, Shouwen; Li, Chang; Wang, Yuhang; Wang, Maopeng; Li, Yi; Yin, Ronglan; Li, Xiao; Ren, Dayong; Qin, Yanqing; Ren, Jingqiang; Jin, Ningyi

    2013-06-01

    This study assessed and compared the immunogenicity of various immunization strategies in mice using combinations of recombinant DNA (pCCMp24) and recombinant attenuated vaccinia virus Tian Tan (rddVTT-CCMp24). Intramuscular immunization was performed on days 0 (prime) and 21 (boost). The immunogenicity of the vaccine schedules was determined by measuring human immunodeficiency virus (HIV)-specific binding antibody levels and cytokine (interleukin-2 and interleukin-4) concentrations in peripheral blood, analyzing lymphocyte proliferation capacity against HIV epitopes and CD4(+)/CD8(+) cell ratio, and monitoring interferon-gamma levels at different times post-immunization. The results showed that pCCMp24, rddVTT-CCMp24 and their prime-boost immunization induced humoral and cellular immune responses. The pCCMp24/rddVTT-CCMp24 immunization strategy increased CD8(+) T cells and induced more IFN-γ-secreting cells compared with single-shot rDNA. The prime-boost immunization strategy also induced the generation of cellular immunological memory to HIV epitope peptides. These results demonstrated that prime-boost immunization with rDNA and rddVTT-CCMp24 had a tendency to induce greater cellular immune response than single-shot vaccinations, especially IFN-γ response, providing a basis for further studies.

  11. Characterization of an attenuated TE3L-deficient vaccinia virus Tian Tan strain.

    Science.gov (United States)

    Wang, Yuhang; Kan, Shifu; Du, Shouwen; Qi, Yanxin; Wang, Jinhui; Liu, Liming; Ji, Huifan; He, Dongyun; Wu, Na; Li, Chang; Chi, Baorong; Li, Xiao; Jin, Ningyi

    2012-12-01

    An attenuated vaccinia virus (VACV), TE3L(-)VTT, was evaluated for virulence and safety to determine its potential use as a vaccine or as a recombinant virus vector to express foreign genes. The virulence of TE3L(-)VTT was compared with that of the wild-type VTT both in vivo and in vitro. The humoral and cellular immune responses were detected in a mouse model to test the vaccine efficacy of the TE3L mutant. The results suggested that deletion of the TE3L gene decreased the virulence and neurovirulence significantly in mice and rabbit models, yet retained the immunogenicity. Thus, the deletion of TE3L improved the safety of the VTT vector; this approach may yield a valuable resource for studies of recombinant VACV-vectored vaccines.

  12. The yellow fever 17D virus as a platform for new live attenuated vaccines.

    Science.gov (United States)

    Bonaldo, Myrna C; Sequeira, Patrícia C; Galler, Ricardo

    2014-01-01

    The live-attenuated yellow fever 17D virus is one of the most outstanding human vaccines ever developed. It induces efficacious immune responses at a low production cost with a well-established manufacture process. These advantages make the YF17D virus attractive as a vector for the development of new vaccines. At the beginning of vector development studies, YF17D was genetically manipulated to express other flavivirus prM and E proteins, components of the viral envelope. While these 17D recombinants are based on the substitution of equivalent YF17D genes, other antigens from unrelated pathogens have also been successfully expressed and delivered by recombinant YF17D viruses employing alternative strategies for genetic manipulation of the YF17D genome. Herein, we discuss these strategies in terms of possibilities of single epitope or larger sequence expression and the main properties of these replication-competent viral platforms.

  13. A novel imageable therapeutic probe for cancer; cytolysin a expressing attenuated salmonella typhimurium

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Vu Hong; Tae, Seong Ho; Piao, Hong Hua; Hong, Yeoung Jin; Choy, Hyon E.; Bom, Hee Seung; Min, Jung Joon [Chonnam National University Medical School, Gwangju (Korea, Republic of)

    2007-07-01

    Oncolytic strategy using bacteria has a long history. With the discovery of fluorescent and luminescent reporter genes, bacteria can be easily monitored continuously in treatment process. Salmonella typhimurium ppGpp mutant, one of the prominent attenuated bacteria, has just reported recently, Therefore, in this study, we established strain Cytolysin A (Cly A) expressing light-emitting S. typhimurium ppGpp mutant. S. typhimurium ppGpp mutant was transducted by lux gene for in vivo imaging (S. typhimurium ppGpp/lux) and then, plasmid containing ClyA gene, which is encoded for a pore-forming protein toxin, was transformed to create the strain expressing haemolytic activity (S. typhimurium ppGpp/lux/ClyA). The toxicity of ClyA was evaluated in vitro by inoculating the bacteria with various cultured cancer cell lines. On the other hand, to test the therapeutic effect, the bacteria were injected intermittently, intraperitoneal y or intravenously into CT26-bearing Balb/c mice. The sizes of tumors were measured and in vivo imaging was taken everyday by IVIS machine (Xenogen). The in vitro result showed the number of death cells were significantly higher in the samples containing S. typhimurium ppGpp/lux/ClyA compared with the samples containing S. typhimurium ppGpp/lux. After two days injection, the growth of tumors were repressed in mice injected with either S. typhimurium ppGpp/lux/ClyA or S. typhimurium ppGpp/lux, while tumors in control group still grew fast. In day 3, the tumors inoculated with S. typhimurium ppGpp/lux/ClyA became necrosis and regressed in the following days but not in other groups. In addition, in vivo imaging data showed that the Salmonella strains selectively located in the tumor. By in vivo imaging technique, the light-emitting bacteria can be easily monitored and quantified non-invasively and repeatedly. And ClyA expressing light-emitting S. typhimurium ppGpp mutant can become an effective and safely candidate for cancer treatment.

  14. Development of live-attenuated arenavirus vaccines based on codon deoptimization of the viral glycoprotein.

    Science.gov (United States)

    Cheng, Benson Y H; Nogales, Aitor; de la Torre, Juan Carlos; Martínez-Sobrido, Luis

    2017-01-15

    Several arenaviruses, chiefly Lassa (LASV) in West Africa, cause hemorrhagic fever (HF) disease in humans and pose important public health problems in their endemic regions. To date, there are no FDA-approved arenavirus vaccines and current anti-arenaviral therapy is limited to the use of ribavirin that has very limited efficacy. In this work we document that a recombinant prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) with a codon deoptimized (CD) surface glycoprotein (GP), rLCMV/CD, exhibited wild type (WT)-like growth properties in cultured cells despite barely detectable GP expression levels in rLCMV/CD-infected cells. Importantly, rLCMV/CD was highly attenuated in vivo but able to induce complete protection against a subsequent lethal challenge with rLCMV/WT. Our findings support the feasibility of implementing an arenavirus GP CD-based approach for the development of safe and effective live-attenuated vaccines (LAVs) to combat diseases caused by human pathogenic arenaviruses.

  15. Tamoxifen-regulated adenoviral E1A chimeras for the control of tumor selective oncolytic adenovirus replication in vitro and in vivo.

    Science.gov (United States)

    Sipo, I; Wang, X; Hurtado Picó, A; Suckau, L; Weger, S; Poller, W; Fechner, H

    2006-01-01

    Pharmacological control is a desirable safety feature of oncolytic adenoviruses (oAdV). It has recently been shown that oAdV replication may be controlled by drug-dependent transcriptional regulation of E1A expression. Here, we present a novel concept that relies on tamoxifen-dependent regulation of E1A activity through functional linkage to the mutated hormone-binding domain of the murine estrogen receptor (Mer). Four different E1A-Mer chimeras (ME, EM, E(DeltaNLS)M, MEM) were constructed and inserted into the adenoviral genome under control of a lung-specific surfactant protein B promoter. The highest degree of regulation in vitro was seen for the corresponding oAdVs Ad.E(DeltaNLS)M and Ad.MEM, which exhibited an up to 100-fold higher oAdV replication in the presence as compared with the absence of 4-OH-tamoxifen. Moreover, destruction of nontarget cells was six- and 13-fold reduced for Ad.E(DeltaNLS)M and Ad.MEM, respectively, as compared with Ad.E. Further investigations supported tamoxifen-dependent regulation of Ad.E(DeltaNLS)M and Ad.MEM in vivo. Induction of Ad.E(DeltaNLS)M inhibited growth of H441 lung tumors as efficient as a control oAdV expressing E1A. E(DeltaNLS)M and the MEM chimeras can be easily inserted into a single vector genome, which extends their application to existing oAdVs and strongly facilitates in vivo application.

  16. Prospective Randomized Phase 2 Trial of Intensity Modulated Radiation Therapy With or Without Oncolytic Adenovirus-Mediated Cytotoxic Gene Therapy in Intermediate-Risk Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Freytag, Svend O., E-mail: sfreyta1@hfhs.org [Department of Radiation Oncology, Henry Ford Health System, Detroit, Michigan (United States); Stricker, Hans [Vattikuti Urology Institute, Henry Ford Health System, Detroit, Michigan (United States); Lu, Mei [Public Health Sciences, Henry Ford Health System, Detroit, Michigan (United States); Elshaikh, Mohamed; Aref, Ibrahim; Pradhan, Deepak; Levin, Kenneth; Kim, Jae Ho [Department of Radiation Oncology, Henry Ford Health System, Detroit, Michigan (United States); Peabody, James [Vattikuti Urology Institute, Henry Ford Health System, Detroit, Michigan (United States); Siddiqui, Farzan; Barton, Kenneth; Pegg, Jan; Zhang, Yingshu; Cheng, Jingfang [Department of Radiation Oncology, Henry Ford Health System, Detroit, Michigan (United States); Oja-Tebbe, Nancy; Bourgeois, Renee [Public Health Sciences, Henry Ford Health System, Detroit, Michigan (United States); Gupta, Nilesh; Lane, Zhaoli [Pathology, Henry Ford Health System, Detroit, Michigan (United States); Rodriguez, Ron [Urology, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); DeWeese, Theodore [Department of Radiation Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); and others

    2014-06-01

    Purpose: To assess the safety and efficacy of combining oncolytic adenovirus-mediated cytotoxic gene therapy (OAMCGT) with intensity modulated radiation therapy (IMRT) in intermediate-risk prostate cancer. Methods and Materials: Forty-four men with intermediate-risk prostate cancer were randomly assigned to receive either OAMCGT plus IMRT (arm 1; n=21) or IMRT only (arm 2; n=23). The primary phase 2 endpoint was acute (≤90 days) toxicity. Secondary endpoints included quality of life (QOL), prostate biopsy (12-core) positivity at 2 years, freedom from biochemical/clinical failure (FFF), freedom from metastases, and survival. Results: Men in arm 1 exhibited a greater incidence of low-grade influenza-like symptoms, transaminitis, neutropenia, and thrombocytopenia than men in arm 2. There were no significant differences in gastrointestinal or genitourinary events or QOL between the 2 arms. Two-year prostate biopsies were obtained from 37 men (84%). Thirty-three percent of men in arm 1 were biopsy-positive versus 58% in arm 2, representing a 42% relative reduction in biopsy positivity in the investigational arm (P=.13). There was a 60% relative reduction in biopsy positivity in the investigational arm in men with <50% positive biopsy cores at baseline (P=.07). To date, 1 patient in each arm exhibited biochemical failure (arm 1, 4.8%; arm 2, 4.3%). No patient developed hormone-refractory or metastatic disease, and none has died from prostate cancer. Conclusions: Combining OAMCGT with IMRT does not exacerbate the most common side effects of prostate radiation therapy and suggests a clinically meaningful reduction in positive biopsy results at 2 years in men with intermediate-risk prostate cancer.

  17. The oncolytic virus dl922-947 reduces IL-8/CXCL8 and MCP-1/CCL2 expression and impairs angiogenesis and macrophage infiltration in anaplastic thyroid carcinoma

    Science.gov (United States)

    Vastolo, Viviana; Di Somma, Sarah; Scamardella, Eloise; Gigantino, Vincenzo; Franco, Renato; Marone, Gianni; Portella, Giuseppe

    2016-01-01

    Anaplastic thyroid carcinoma (ATC) is one of the most aggressive human solid tumor and current treatments are ineffective in increasing patients' survival. Thus, the development of new therapeutic approaches for ATC is needed. We have previously shown that the oncolytic adenovirus dl922-947 induces ATC cell death in vitro and tumor regression in vivo. However, the impact of dl922-947 on the pro-tumorigenic ATC microenvironment is still unknown. Since viruses are able to regulate cytokine and chemokine production from infected cells, we sought to investigate whether dl922-947 virotherapy has such effect on ATC cells, thereby modulating ATC microenvironment. dl922-947 decreased IL-8/CXCL8 and MCP-1/CCL2 production by the ATC cell lines 8505-c and BHT101-5. These results correlated with dl922-947-mediated reduction of NF-κB p65 binding to IL8 promoter in 8505-c and BHT101-5 cells and CCL2 promoter in 8505-c cells. IL-8 stimulates cancer cell proliferation, survival and invasion, and also angiogenesis. dl922-947-mediated reduction of IL-8 impaired ATC cell motility in vitro and ATC-induced angiogenesis in vitro and in vivo. We also show that dl922-947-mediated reduction of the monocyte-attracting chemokine CCL2 decreased monocyte chemotaxis in vitro and tumor macrophage density in vivo. Interestingly, dl922-947 treatment induced the switch of tumor macrophages toward a pro-inflammatory M1 phenotype, likely by increasing the expression of the pro-inflammatory cytokine interferon-γ. Altogether, we demonstrate that dl922-947 treatment re-shape the pro-tumorigenic ATC microenvironment by modulating cancer-cell intrinsic factors and the immune response. An in-depth knowledge of dl922-947-mediated effects on ATC microenvironment may help to refine ATC virotherapy in the context of cancer immunotherapy. PMID:26625205

  18. CRMAGE: CRISPR Optimized MAGE Recombineering

    DEFF Research Database (Denmark)

    Ronda, Carlotta; Pedersen, Lasse Ebdrup; Sommer, Morten Otto Alexander

    2016-01-01

    A bottleneck in metabolic engineering and systems biology approaches is the lack of efficient genome engineering technologies. Here, we combine CRISPR/Cas9 and λ Red recombineering based MAGE technology (CRMAGE) to create a highly efficient and fast method for genome engineering of Escherichia coli...... that are assembled by a USER-cloning approach enabling quick and cost efficient gRNA replacement. CRMAGE furthermore utilizes CRISPR/Cas9 for efficient plasmid curing, thereby enabling multiple engineering rounds per day. To facilitate the design process, a web-based tool was developed to predict both the λ Red...

  19. Recombinant DNA technology in apple.

    Science.gov (United States)

    Gessler, Cesare; Patocchi, Andrea

    2007-01-01

    This review summarizes the achievements of almost 20 years of recombinant DNA technology applied to apple, grouping the research results into the sections: developing the technology, insect resistance, fungal disease resistance, self-incompatibility, herbicide resistance, fire blight resistance, fruit ripening, allergens, rooting ability, and acceptance and risk assessment. The diseases fire blight, caused by Erwinia amylovora, and scab, caused by Venturia inaequalis, were and still are the prime targets. Shelf life improvement and rooting ability of rootstocks are also relevant research areas. The tools to create genetically modified apples of added value to producers, consumers, and the environment are now available.

  20. Attenuation of diacylglycerol second messengers

    Energy Technology Data Exchange (ETDEWEB)

    Bishop, W.R.; Ganong, B.R.; Bell, R.M.

    1986-05-01

    Diacylglycerol(DAG) derived from phosphatidylinositol activates protein kinase C in agonist-stimulated cells. At least two pathways may contribute to the attenuation of the DAG signal: (1) phosphorylation to phosphatidic acid(PA) by DAG kinase(DGK), and (2) deacylation by DAG and monoacylglycerol lipases. A number of DAG analogs were tested as substrates and inhibitors of partially purified pig brain DGK. Two analogs were potent inhibitors in vitro, 1-monooleoylglycerol(MOG,K/sub I/ = 91 ..mu..M) and diotanoylethyleneglycol (diC/sub 8/EG, K/sub I/ = 58 ..mu..M). These compounds were tested in human platelets. DiC/sub 8/EG inhibited (70 - 100%) (/sup 32/P/sub i/) incorporation into PA in thrombin-stimulated platelets. Under these conditions the DAG signal was somewhat long-lived but was still metabolized, presumably by the lipase pathway. MOG treatment elevated DAG levels up to 4-fold in unstimulated platelets. The DAG formed was in a pool where it did not activate protein kinase C. Thrombin-stimulation of MOG-treated platelets resulted in DAG levels 10-fold higher than control platelets. This appears to be due to the inability of these platelets to metabolize agonist-linked DAG via the lipase pathway. The development of specific inhibitors of DAG kinase and DAG lipase, in conjunction with mass quantification of DAG levels as used here, will provide further insights into the regulation of DAG second messengers.

  1. Live attenuated intranasal influenza vaccine.

    Science.gov (United States)

    Esposito, Susanna; Montinaro, Valentina; Groppali, Elena; Tenconi, Rossana; Semino, Margherita; Principi, Nicola

    2012-01-01

    Annual vaccination is the most effective means of preventing and controlling influenza epidemics, and the traditional trivalent inactivated vaccine (TIV) is by far the most widely used. Unfortunately, it has a number of limitations, the most important of which is its poor immunogenicity in younger children and the elderly, the populations at greatest risk of severe influenza. Live attenuated influenza vaccine (LAIV) has characteristics that can overcome some of these limitations. It does not have to be injected because it is administered intranasally. It is very effective in children and adolescents, among whom it prevents significantly more cases of influenza than the traditional TIV. However, its efficacy in adults has not been adequately documented, which is why it has not been licensed for use by adults by the European health authorities. LAIV is safe and well tolerated by children aged > 2 y and adults, but some concerns arisen regarding its safety in younger children and subjects with previous asthma or with recurrent wheezing. Further studies are needed to solve these problems and to evaluate the possible role of LAIV in the annual vaccination of the general population.

  2. aroA-Deficient Salmonella enterica Serovar Typhimurium Is More Than a Metabolically Attenuated Mutant

    Directory of Open Access Journals (Sweden)

    Sebastian Felgner

    2016-09-01

    Full Text Available Recombinant attenuated Salmonella enterica serovar Typhimurium strains are believed to act as powerful live vaccine carriers that are able to elicit protection against various pathogens. Auxotrophic mutations, such as a deletion of aroA, are commonly introduced into such bacteria for attenuation without incapacitating immunostimulation. In this study, we describe the surprising finding that deletion of aroA dramatically increased the virulence of attenuated Salmonella in mouse models. Mutant bacteria lacking aroA elicited increased levels of the proinflammatory cytokine tumor necrosis factor alpha (TNF-α after systemic application. A detailed genetic and phenotypic characterization in combination with transcriptomic and metabolic profiling demonstrated that ΔaroA mutants display pleiotropic alterations in cellular physiology and lipid and amino acid metabolism, as well as increased sensitivity to penicillin, complement, and phagocytic uptake. In concert with other immunomodulating mutations, deletion of aroA affected flagellin phase variation and gene expression of the virulence-associated genes arnT and ansB. Finally, ΔaroA strains displayed significantly improved tumor therapeutic activity. These results highlight the importance of a functional shikimate pathway to control homeostatic bacterial physiology. They further highlight the great potential of ΔaroA-attenuated Salmonella for the development of vaccines and cancer therapies with important implications for host-pathogen interactions and translational medicine.

  3. Atomic excitation and recombination in external fields

    Energy Technology Data Exchange (ETDEWEB)

    Nayfeh, M.H.; Clark, C.W.

    1985-01-01

    This volume offers a timely look at Rydberg states of atoms in external fields and dielectronic recombination. Each topic provides authoritative coverage, presents a fresh account of a flourishing field of current atomic physics and introduces new opportunities for discovery and development. Topics considered include electron-atom scattering in external fields; observations of regular and irregular motion as exemplified by the quadratic zeeman effect and other systems; Rydberg atoms in external fields and the Coulomb geometry; crossed-field effects in the absorption spectrum of lithium in a magnetic field; precise studies of static electric field ionization; widths and shapes of stark resonances in sodium above the saddle point; studies of electric field effects and barium autoionizing resonances; autoionization and dielectronic recombination in plasma electric microfields; dielectronic recombination measurements on multicharged ions; merged beam studies of dielectronic recombination; Rydberg atoms and dielectronic recombination in astrophysics; and observations on dielectronic recombination.

  4. Detecting the cosmological recombination signal from space

    CERN Document Server

    Desjacques, Vincent; Silk, Joseph; de Bernardis, Francesco; Doré, Olivier

    2015-01-01

    Spectral distortions of the CMB have recently experienced an increased interest. One of the inevitable distortion signals of our cosmological concordance model is created by the cosmological recombination process, just a little before photons last scatter at redshift $z\\simeq 1100$. These cosmological recombination lines, emitted by the hydrogen and helium plasma, should still be observable as tiny deviation from the CMB blackbody spectrum in the cm--dm spectral bands. In this paper, we present a forecast for the detectability of the recombination signal with future satellite experiments. We argue that serious consideration for future CMB experiments in space should be given to probing spectral distortions and, in particular, the recombination line signals. The cosmological recombination radiation not only allows determination of standard cosmological parameters, but also provides a direct observational confirmation for one of the key ingredients of our cosmological model: the cosmological recombination histo...

  5. HUMAN PAPILLOMAVIRUS TYPE 16 L1 PROTEIN CAN BE EXPRESSED IN LIVE ATTENUATED SHIGELLA FLEXNERI 5A STRAIN SH42

    Institute of Scientific and Technical Information of China (English)

    Qu Xinzhong; Yang Xiaofeng; Zheng Jin; Wang Kai; Si Lüsheng; Wang Yili

    2005-01-01

    Objective Attenuated strains of Shigella are attractive live vaccine candidates for eliciting mucosal immune responses which is a suitable carrier for the prophylactic human papillomaviruses (HPV) vaccine development, To examine the potential of a live Shigella based prophylactic HPV vaccine, HPV16L1should be expressed in attenuated shigella strain. Methods A Shigella large invasive plasmid (icsA/virG) based prokaryotic expression plasmid pHS3199 was constructed. HPV16L1 gene was inserted into plasmid pHS3199 to form pHS3199-HPV16 L1 construct, and pHS3199-hpv16L1 was electroporated into a live attenuated shigella strain sh42. The expression of HPV16L1 protein was demonstrated by Western blotting with monoclonal antibody to HPV16L1, The genetic stability of recombinant strain sh42-HPV16 L1 was monitored by consecutive passage culture. Invasive ability of sh42-HPV16L1 was evaluated by Hela cell infection assay. Results HPV16 L1 protein can be expressed in recombinant strain sh42-HPV16 L1, and the protein stably expressed over 140 generations. The invasive ability of sh42-HPV16L1 was diminished dramatically compared to its parent strain, but not abolished completely. Conclusion HPV16L1 protein was constitutively expressed in the attenuated strain of shigella flexneri sh42, and maintained partial invasive ability. Our strategy may represent a promising vaccine candidate against genital HPV16 infection.

  6. V(D)J recombination frequency is affected by the sequence interposed between a pair of recombination signals: sequence comparison reveals a putative recombinational enhancer element

    DEFF Research Database (Denmark)

    Roch, F A; Hobi, R; Berchtold, M W;

    1997-01-01

    The immunoglobulin heavy chain intron enhancer (Emu) not only stimulates transcription but also V(D)J recombination of chromosomally integrated recombination substrates. We aimed at reproducing this effect in recombination competent cells by transient transfection of extrachromosomal substrates. ...

  7. Specific anti-tumor effect induced by attenuated Salmonella typhimurium vaccine expressing extracellular region of vascular endothelial growth factor receptor 2

    Institute of Scientific and Technical Information of China (English)

    YANG Jun; DONG Jian; PU Ping; WANG ZhiQiang; HONG Min; CHEN MingQing

    2008-01-01

    The purposes of this research were to study the stable expression of exogenous gene encoding therapeutic protein in attenuated Salmonella typhimurium, observe the metabolism of oral gene vac-cine carried by attenuated Salmonella typhimurium in BALB/c mouse, and investigate the feasibility of prevention and treatment of tumors by the recombinant bacteria. Recombinant plasmid pcDNA3.1+ VEGFR2(n1-7) was transformed into competent attenuated Salmonella typhimurium SL3261 to develop oral DNA vaccine SL3261-pcDNA3.1+VEGFR2(n1-7). To observe whether the exogenous gene can be ex-pressed in the recombinant bacteria, PCR was performed to amplify the CMV promoter of the eu-karyotic expression vector as the proof of stable expression of exogenous protein; transmission elec-tron microscopy (TEM) was applied to observe the morphology of the recombinant bacteria to confirm that the exogenous gene has no impact on the growth of the bacteria, and then BALB/c mice were immunized with the gene vaccine. After inoculation of the gene vaccine, the recombinant bacteria SL3261 could be detected in the tissues such as small intestine, colon, liver and spleen. And then, mice in each group were challenged with tumor cells. The results of animal experiment showed that tumor growth of the mice in experimental group was inhibited and survival time of immunized mice was pro-longed compared with control groups. A higher lymphocyte infiltration in tumors from animals treated with DNA vaccine was observed. Immunohistochemical analysis of tumor samples revealed an en-hanced accumulation of CD8+ cytotoxic T lymphocytes, as well as an increase in CD4+ cells in the tu-mors of animals treated with the oral gene vaccine compared to tumors from control group mice. UI-trastructure of the tumor tissue showed that tumor cells in the samples of the immunized mice were well-differentiated. Our research confirmed that the exogenous gene can be stably expressed in the attenuated Salmonella typhimurium and has no

  8. The homologous recombination system of Ustilago maydis

    OpenAIRE

    Holloman, William K.; Schirawski, Jan; Holliday, Robin

    2008-01-01

    Homologous recombination is a high fidelity, template-dependent process that is used in repair of damaged DNA, recovery of broken replication forks, and disjunction of homologous chromosomes in meiosis. Much of what is known about recombination genes and mechanisms comes from studies on baker's yeast. Ustilago maydis, a basidiomycete fungus, is distant evolutionarily from baker's yeast and so offers the possibility of gaining insight into recombination from an alternative perspective. Here we...

  9. Role of ubiquitination in meiotic recombination repair

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Programmed and unprogrammed double-strand breaks (DSBs) often arise from such physiological requirements as meiotic recombination, and exogenous insults, such as ionizing radiation (IR). Due to deleterious impacts on genome stability, DSBs must be appropriately processed and repaired in a regulatory manner. Recent investigations have indicated that ubiquitination is a critical factor in DNA damage response and meiotic recombination repair. This review summarizes the effects of proteins and complexes associated with ubiquitination with regard to homologous recombination (HR)-dependent DSB repair.

  10. Recombinant DNA production of spider silk proteins.

    Science.gov (United States)

    Tokareva, Olena; Michalczechen-Lacerda, Valquíria A; Rech, Elíbio L; Kaplan, David L

    2013-11-01

    Spider dragline silk is considered to be the toughest biopolymer on Earth due to an extraordinary combination of strength and elasticity. Moreover, silks are biocompatible and biodegradable protein-based materials. Recent advances in genetic engineering make it possible to produce recombinant silks in heterologous hosts, opening up opportunities for large-scale production of recombinant silks for various biomedical and material science applications. We review the current strategies to produce recombinant spider silks.

  11. Impact of recombination on bacterial evolution

    OpenAIRE

    2010-01-01

    Genetic exchange plays a defining role in the evolution of many bacteria. The recent accumulation of nucleotide sequence data from multiple members of diverse bacterial genera has facilitated comparative studies that have revealed many features of this process. Here we focus on genetic exchange that has involved homologous recombination and illustrate how nucleotide sequence data have furthered our understanding of: (i) the frequency of recombination; (ii) the impact of recombination in diffe...

  12. RNA recombination in animal and plant viruses.

    OpenAIRE

    1992-01-01

    An increasing number of animal and plant viruses have been shown to undergo RNA-RNA recombination, which is defined as the exchange of genetic information between nonsegmented RNAs. Only some of these viruses have been shown to undergo recombination in experimental infection of tissue culture, animals, and plants. However, a survey of viral RNA structure and sequences suggests that many RNA viruses were derived form homologous or nonhomologous recombination between viruses or between viruses ...

  13. Rapid purification of recombinant histones.

    Directory of Open Access Journals (Sweden)

    Henrike Klinker

    Full Text Available The development of methods to assemble nucleosomes from recombinant histones decades ago has transformed chromatin research. Nevertheless, nucleosome reconstitution remains time consuming to this day, not least because the four individual histones must be purified first. Here, we present a streamlined purification protocol of recombinant histones from bacteria. We termed this method "rapid histone purification" (RHP as it circumvents isolation of inclusion bodies and thereby cuts out the most time-consuming step of traditional purification protocols. Instead of inclusion body isolation, whole cell extracts are prepared under strongly denaturing conditions that directly solubilize inclusion bodies. By ion exchange chromatography, the histones are purified from the extracts. The protocol has been successfully applied to all four canonical Drosophila and human histones. RHP histones and histones that were purified from isolated inclusion bodies had similar purities. The different purification strategies also did not impact the quality of octamers reconstituted from these histones. We expect that the RHP protocol can be readily applied to the purification of canonical histones from other species as well as the numerous histone variants.

  14. Graphene-based Electronically Tuneable Microstrip Attenuator

    Directory of Open Access Journals (Sweden)

    L. Pierantoni

    2014-06-01

    Full Text Available This paper presents the design of a graphene- based electronically tuneable microstrip attenuator operating at a frequency of 5 GHz. The use of graphene as a variable resistor is discussed and the modelling of its electromagnetic properties at microwave frequencies is fully addressed. The design of the graphene-based attenuator is described. The structure integrates a patch of graphene, whose characteristics can range from being a fairly good conductor to a highly lossy material, depending on the applied voltage. By applying the proper voltage through two high-impedance bias lines, the surface resistivity of graphene can be modified, thereby changing the insertion loss of the microstrip attenuator.

  15. Experimental recombination rates for highly charged ions

    Energy Technology Data Exchange (ETDEWEB)

    Reinhold Schuch [Dept. of Atomic Physics, Stockholm Univ., Frescativ., Stockholm (Sweden)

    2000-01-01

    Recent studies of recombination between free electrons and highly charged ions using electron coolers of heavy-ion storage rings have produced accurate rate coefficients of interest for plasma modeling and diagnostics. Some surprises were discovered which can lead to revisions of recombination models. With bare ions one finds at low energy a strong and puzzling deviation from radiative recombination theory. Dielectronic recombination with C3+, N4+ show that jj coupling gives essential contributions to the cross section also for light ions. (author)

  16. Human Insulin from Recombinant DNA Technology

    Science.gov (United States)

    Johnson, Irving S.

    1983-02-01

    Human insulin produced by recombinant DNA technology is the first commercial health care product derived from this technology. Work on this product was initiated before there were federal guidelines for large-scale recombinant DNA work or commercial development of recombinant DNA products. The steps taken to facilitate acceptance of large-scale work and proof of the identity and safety of such a product are described. While basic studies in recombinant DNA technology will continue to have a profound impact on research in the life sciences, commercial applications may well be controlled by economic conditions and the availability of investment capital.

  17. A Recombinant Vesicular Stomatitis Virus Ebola Vaccine.

    Science.gov (United States)

    Regules, Jason A; Beigel, John H; Paolino, Kristopher M; Voell, Jocelyn; Castellano, Amy R; Hu, Zonghui; Muñoz, Paula; Moon, James E; Ruck, Richard C; Bennett, Jason W; Twomey, Patrick S; Gutiérrez, Ramiro L; Remich, Shon A; Hack, Holly R; Wisniewski, Meagan L; Josleyn, Matthew D; Kwilas, Steven A; Van Deusen, Nicole; Mbaya, Olivier Tshiani; Zhou, Yan; Stanley, Daphne A; Jing, Wang; Smith, Kirsten S; Shi, Meng; Ledgerwood, Julie E; Graham, Barney S; Sullivan, Nancy J; Jagodzinski, Linda L; Peel, Sheila A; Alimonti, Judie B; Hooper, Jay W; Silvera, Peter M; Martin, Brian K; Monath, Thomas P; Ramsey, W Jay; Link, Charles J; Lane, H Clifford; Michael, Nelson L; Davey, Richard T; Thomas, Stephen J

    2017-01-26

    Background The worst Ebola virus disease (EVD) outbreak in history has resulted in more than 28,000 cases and 11,000 deaths. We present the final results of two phase 1 trials of an attenuated, replication-competent, recombinant vesicular stomatitis virus (rVSV)-based vaccine candidate designed to prevent EVD. Methods We conducted two phase 1, placebo-controlled, double-blind, dose-escalation trials of an rVSV-based vaccine candidate expressing the glycoprotein of a Zaire strain of Ebola virus (ZEBOV). A total of 39 adults at each site (78 participants in all) were consecutively enrolled into groups of 13. At each site, volunteers received one of three doses of the rVSV-ZEBOV vaccine (3 million plaque-forming units [PFU], 20 million PFU, or 100 million PFU) or placebo. Volunteers at one of the sites received a second dose at day 28. Safety and immunogenicity were assessed. Results The most common adverse events were injection-site pain, fatigue, myalgia, and headache. Transient rVSV viremia was noted in all the vaccine recipients after dose 1. The rates of adverse events and viremia were lower after the second dose than after the first dose. By day 28, all the vaccine recipients had seroconversion as assessed by an enzyme-linked immunosorbent assay (ELISA) against the glycoprotein of the ZEBOV-Kikwit strain. At day 28, geometric mean titers of antibodies against ZEBOV glycoprotein were higher in the groups that received 20 million PFU or 100 million PFU than in the group that received 3 million PFU, as assessed by ELISA and by pseudovirion neutralization assay. A second dose at 28 days after dose 1 significantly increased antibody titers at day 56, but the effect was diminished at 6 months. Conclusions This Ebola vaccine candidate elicited anti-Ebola antibody responses. After vaccination, rVSV viremia occurred frequently but was transient. These results support further evaluation of the vaccine dose of 20 million PFU for preexposure prophylaxis and suggest that a

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

    Directory of Open Access Journals (Sweden)

    Juana M Sánchez-Puig

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

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

    Science.gov (United States)

    Sánchez-Puig, Juana M; Lorenzo, María M; Blasco, Rafael

    2013-01-01

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

  20. [Modified vaccinia virus ankara (MVA)--development as recombinant vaccine and prospects for use in veterinary medicine].

    Science.gov (United States)

    Volz, Asisa; Fux, Robert; Langenmayer, Martin C; Sutter, Gerd

    2015-01-01

    Poxviruses as expression vectors are widely used in medical research for the development of recombinant vaccines and molecular therapies. Here we review recent accomplishments in vaccine research using recombinant modified vaccinia virus ankara (MVA). MVA is a highly attenuated vaccinia virus strain that originated from serial tissue culture passage in chicken embryo fibroblasts more than 40 years ago. Growth adaptation to avian host cells caused deletions and mutations in the viral genome affecting about 15% of the original genetic information. In consequence, MVA is replication-deficient in cells of mammalian origin and fails to produce many of the virulence factors encoded by conventional vaccinia virus. Because of its safety for the general environment MVA can be handled under conditions of biosafety level one. Non-replicating MVA can enter any target cell and activate its molecular life cycle to express all classes of viral and recombinant genes. Therefore, recombinant MVA have been established as an extremely safe and efficient vector system for vaccine development in medical research. By now, various recombinant MVA vaccines have been found safe and immunogenic when used for phase I/II clinical testing in humans, and suitable for industrial scale production following good practice of manufacturing. Thus, there is an obvious usefulness of recombinant MVA vaccines for novel prophylactic and therapeutic approaches also in veterinary medicine. Results from first studies in companion and farm animals are highly promising.

  1. Precision Model for Microwave Rotary Vane Attenuator

    DEFF Research Database (Denmark)

    Guldbrandsen, Tom

    1979-01-01

    A model for a rotary vane attenuator is developed to describe the attenuator reflection and transmission coefficients in detail. All the parameters of the model can be measured in situ, i.e., without diassembling any part. The tranmission errors caused by internal reflections are calculated from ...... measurements of the much larger reflection parameters, hence commonly used nonprecision instruments can be used to determine the transmission errors with sufficient accuracy for the highest precision obtainable in standard laboratories....

  2. Wave attenuation charcteristics of tethered float system

    Digital Repository Service at National Institute of Oceanography (India)

    Vethamony, P.

    and transmitted wave powers, transmission coefficients are computed. The results show that transmission coefficient does not vary with changes in wave height or water depth. When depth of submergence of float increases, wave attenuation decreases, showing... that the system performs well when it is just submerged. As float velocity decreases with increase in float size, transmission coefficient increases with increase in float size. The influence of wave period on wave attenuation is remarkable compared to other...

  3. ATTENUATION AND FLANKING TRANSMISSION IN LIGHTWEIGHT STRUCTURES

    DEFF Research Database (Denmark)

    Brunskog, Jonas; Lhomond, Alice; Ohlrich, Mogens

    2007-01-01

    In this paper the attenuation and flanking transmissions of impact noise in lightweight building structures is studied using a modal approach. The structural field is mainly analysed, putting the main attention to the parts being important in the modelling. The amount of attenuation produced...... by the periodically reinforcing beams used in lightweight building structures is analysed. The consequence of these factors in modelling flanking transmission is also discussed....

  4. Construction of recombinant pseudorabies viruses by using PRV BACs deficient in IE180 or pac sequences: Application of vBAC90D recombinant virus to production of PRV amplicons.

    Science.gov (United States)

    Lerma, L; Muñoz, A L; Wagner, S; Dinu, M; Martín, B; Tabarés, E

    2016-02-02

    We describe a simple and efficient method to obtain recombinant pseudorabies virus (PRV) in mammalian cells by using the PRV BACs, PBAC80 deficient in pac sequences and PBAC90 deficient in the IE180 gene. These essential viral sequences were used as targets to obtain viable recombinant viruses. PBAC80 was constructed, confirmed to encode a copy of the IE180 gene regulated by the inducible Ptet promoter, and used to obtain recombinant attenuated PRV viruses that express the EGFP protein (PRV-BT80GF virus). PBAC90 was used to obtain the vBAC90D virus, deficient in IE180 and free of replication-competent revertants, and which can be used as a helper in the production of PRV amplicons.

  5. Light attenuation in estuarine mangrove lakes

    Science.gov (United States)

    Frankovich, Thomas A.; Rudnick, David T.; Fourqurean, James W.

    2017-01-01

    Submerged aquatic vegetation (SAV) cover has declined in brackish lakes in the southern Everglades characterized by low water transparencies, emphasizing the need to evaluate the suitability of the aquatic medium for SAV growth and to identify the light attenuating components that contribute most to light attenuation. Underwater attenuation of downwards irradiance of photosynthetically active radiation (PAR) was determined over a three year period at 42 sites in shallow (lakes in two sub-estuaries in the coastal Everglades, Florida USA. Turbidity, chromophoric dissolved organic matter (CDOM), and phytoplankton chlorophyll a (chl a) were measured concurrently and their respective contributions to the light attenuation rate were estimated. Light transmission to the benthos relative to literature estimates of minimum requirements for SAV growth indicated that the underwater light environment was often unsuitable for SAV. Light attenuation rates (n = 417) corrected for solar elevation angles ranged from 0.16 m-1 to 9.83 m-1 with a mean of 1.73 m-1. High concentrations of CDOM with high specific light absorption contributed the most to light attenuation followed by turbidity and chl a. CDOM alone sufficiently reduces light transmission beyond the estimated limits for SAV growth, making it difficult for ecosystem managers to increase SAV abundance by management activities. Light limitation of SAV in these areas may be a persistent feature because of their proximity to CDOM source materials from the surrounding mangrove swamp. Increasing freshwater flow into these areas may dilute CDOM concentrations and improve the salinity and light climate for SAV communities.

  6. Dielectronic recombination of tungsten ions

    Science.gov (United States)

    Li, Bowen; O'Sullivan, Gerry; Dong, Chenzhong; Chen, Ximeng

    2016-08-01

    Ab initio calculations of dielectronic recombination rate coefficients of Ne-, Pd- and Ag-like tungsten have been performed. Energy levels, radiative transition probabilities and autoionization rates were calculated using the Flexible Atomic Code. The contributions from different channels to the total rate coefficients are discussed. The present calculated rate coefficients are compared with other calculations where available. Excellent agreement has been found for Ne-like W while a large discrepancy was found for Pd-like W, which implies that more ab initio calculations and experimental measurements are badly needed. Further calculations demonstrated that the influence of configuration interaction is small while nonresonant radiative stabilizing (NRS) contribution to doubly excited non-autoionizing states are vital. The data obtained are expected to be useful for modeling plasmas for fusion applications, especially for the ITER community, which makes experimental verification even more essential.

  7. Fundamental Studies of Recombinant Hydrogenases

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Michael W

    2014-01-25

    This research addressed the long term goals of understanding the assembly and organization of hydrogenase enzymes, of reducing them in size and complexity, of determining structure/function relationships, including energy conservation via charge separation across membranes, and in screening for novel H2 catalysts. A key overall goal of the proposed research was to define and characterize minimal hydrogenases that are produced in high yields and are oxygen-resistant. Remarkably, in spite of decades of research carried out on hydrogenases, it is not possible to readily manipulate or design the enzyme using molecular biology approaches since a recombinant form produced in a suitable host is not available. Such resources are essential if we are to understand what constitutes a “minimal” hydrogenase and design such catalysts with certain properties, such as resistance to oxygen, extreme stability and specificity for a given electron donor. The model system for our studies is Pyrococcus furiosus, a hyperthermophile that grows optimally at 100°C, which contains three different nickel-iron [NiFe-] containing hydrogenases. Hydrogenases I and II are cytoplasmic while the other, MBH, is an integral membrane protein that functions to both evolve H2 and pump protons. Three important breakthroughs were made during the funding period with P. furiosus soluble hydrogenase I (SHI). First, we produced an active recombinant form of SHI in E. coli by the co-expression of sixteen genes using anaerobically-induced promoters. Second, we genetically-engineered P. furiosus to overexpress SHI by an order of magnitude compared to the wild type strain. Third, we generated the first ‘minimal’ form of SHI, one that contained two rather than four subunits. This dimeric form was stable and active, and directly interacted with a pyruvate-oxidizing enzyme with any intermediate electron carrier. The research resulted in five peer-reviewed publications.

  8. Titania Photocatalysis beyond Recombination: A Critical Review

    Directory of Open Access Journals (Sweden)

    Bunsho Ohtani

    2013-11-01

    Full Text Available This short review paper shows the significance of recombination of a photoexcited electron and a hole in conduction and valence bands, respectively, of a titania photocatalyst, since recombination has not yet been fully understood and has not been evaluated adequately during the past several decades of research on heterogeneous photocatalysis.

  9. Cell biology of homologous recombination in yeast

    DEFF Research Database (Denmark)

    Eckert-Boulet, Nadine Valerie; Rothstein, Rodney; Lisby, Michael

    2011-01-01

    Homologous recombination is an important pathway for error-free repair of DNA lesions, such as single- and double-strand breaks, and for rescue of collapsed replication forks. Here, we describe protocols for live cell imaging of single-lesion recombination events in the yeast Saccharomyces...

  10. Theoretic Study of CⅡ Recombination Line

    Institute of Scientific and Technical Information of China (English)

    彭永伦; 王民盛; 韩小英; 李家明

    2004-01-01

    Using the R-matrix method, we carry out theoretical calculations for recombination line λ 8794 A(3d'-3p') of CⅡ, which is important to estimate the abundances of carbon in planetary nebulae. Our calculations are based on three sets of target orbital basis, through which we elucidate the electron correlation and static polarization effects in the dielectronic recombination processes.

  11. RNAi and heterochromatin repress centromeric meiotic recombination

    DEFF Research Database (Denmark)

    Ellermeier, Chad; Higuchi, Emily C; Phadnis, Naina

    2010-01-01

    During meiosis, the formation of viable haploid gametes from diploid precursors requires that each homologous chromosome pair be properly segregated to produce an exact haploid set of chromosomes. Genetic recombination, which provides a physical connection between homologous chromosomes, is essen......During meiosis, the formation of viable haploid gametes from diploid precursors requires that each homologous chromosome pair be properly segregated to produce an exact haploid set of chromosomes. Genetic recombination, which provides a physical connection between homologous chromosomes....... Surprisingly, one mutant derepressed for recombination in the heterochromatic mating-type region during meiosis and several mutants derepressed for centromeric gene expression during mitotic growth are not derepressed for centromeric recombination during meiosis. These results reveal a complex relation between...... types of repression by heterochromatin. Our results also reveal a previously undemonstrated role for RNAi and heterochromatin in the repression of meiotic centromeric recombination and, potentially, in the prevention of birth defects by maintenance of proper chromosome segregation during meiosis....

  12. Recombinant vaccines: experimental and applied aspects

    DEFF Research Database (Denmark)

    Lorenzen, Niels

    1999-01-01

    Development of vaccines for aquaculture fish represent an important applied functional aspect of fish immunology research. Particularly in the case of recombinant vaccines, where a single antigen is usually expected to induce immunity to a specific pathogen, knowledge of mechanisms involved in in......, these fields will open up a number of interesting research objectives of mutual benefit. Recent aspects of recombinant protein vaccines, live recombinant vaccines and DNA vaccines are discussed.......Development of vaccines for aquaculture fish represent an important applied functional aspect of fish immunology research. Particularly in the case of recombinant vaccines, where a single antigen is usually expected to induce immunity to a specific pathogen, knowledge of mechanisms involved...... in induction of a protective immune response may become vital. The few recombinant vaccines licensd so far, despite much research during the last decade, illustrate that this is not a straightforward matter. However, as vaccine technology as well as our knowledge of the fish immune system is steadily improved...

  13. Construction of an oral recombinant DNA vaccine from H pylori neutrophil activating protein and its immunogenicity

    Institute of Scientific and Technical Information of China (English)

    Bo Sun; Zhao-Shen Li; Zhen-Xing Tu; Guo-Ming Xu; Yi-Qi Du

    2006-01-01

    AIM: To construct a live attenuated Salmonella typhimurium (S.typhimurium) strain harboring the H pylori neutrophil activating protein (HP-NAP) gene as an oral recombinant DNA vaccine, and to evaluate its immunogenicity.METHODS: By genetic engineering methods, the genomic DNA of H pylori was extracted as a template. The total length of the HP-NAP gene was amplified by polymerase chain reaction (PCR) and cloned into pBT vector for sequencing and BLAST analysis, then subcloned into a eukaryotic expression vector pIRES followed by PCR identification and restriction enzyme digestion. The identified recombinant plasmid pIRES-NAP was transfected into COS-7 cells for target fusion protein expression, and its antigenicity was detected by Western blotting. Then the recombinant plasmid was transformed into a live attenuated S. typhimurium strain SL7207 as an oral vaccine strain, and its immunogenicity was evaluated with animal experiments.RESULTS: A 435 bp product was cloned using high homology with HP-NAP gene in GenBank (more than 98%). With identification by PCR and restriction enzyme digestion, a recompinant eukaryotic expression plasmid pIRES-NAP containing the HP-NAP gene of H pylori was successfully constructed. The expressed target protein had a specific reaction with H pylor(i) whole cell antibody and showed a single strip result detected by Western blotting. Oral immunization of mice with recombinant DNA vaccine strain SL7207 (pIRES-NAP) also induced a specific immune response.CONCLUSION: The successful construction of HP-NAP oral DNA vaccine with good immunogenicity may help to further investigate its immunoprotection effects and develop vaccine against H pylori infection.

  14. The recombinational anatomy of a mouse chromosome.

    Directory of Open Access Journals (Sweden)

    Kenneth Paigen

    2008-07-01

    Full Text Available Among mammals, genetic recombination occurs at highly delimited sites known as recombination hotspots. They are typically 1-2 kb long and vary as much as a 1,000-fold or more in recombination activity. Although much is known about the molecular details of the recombination process itself, the factors determining the location and relative activity of hotspots are poorly understood. To further our understanding, we have collected and mapped the locations of 5,472 crossover events along mouse Chromosome 1 arising in 6,028 meioses of male and female reciprocal F1 hybrids of C57BL/6J and CAST/EiJ mice. Crossovers were mapped to a minimum resolution of 225 kb, and those in the telomere-proximal 24.7 Mb were further mapped to resolve individual hotspots. Recombination rates were evolutionarily conserved on a regional scale, but not at the local level. There was a clear negative-exponential relationship between the relative activity and abundance of hotspot activity classes, such that a small number of the most active hotspots account for the majority of recombination. Females had 1.2x higher overall recombination than males did, although the sex ratio showed considerable regional variation. Locally, entirely sex-specific hotspots were rare. The initiation of recombination at the most active hotspot was regulated independently on the two parental chromatids, and analysis of reciprocal crosses indicated that parental imprinting has subtle effects on recombination rates. It appears that the regulation of mammalian recombination is a complex, dynamic process involving multiple factors reflecting species, sex, individual variation within species, and the properties of individual hotspots.

  15. Interleukin-11 attenuates ifosfamide-induced hemorrhagic cystitis

    Directory of Open Access Journals (Sweden)

    Jose M. Mota

    2007-10-01

    Full Text Available OBJECTIVE: To investigate the possible protective effect of recombinant human interleukin-11 (rhIL-11 against ifosfamide (IFS-induced hemorrhagic cystitis (HC MATERIALS AND METHODS: Male Swiss mice (20-30g were pretreated with rhIL-11 (25-625 mg, subcutaneously. 30 min before intraperitoneal injection of IFS (400 mg/kg or with saline (control group. Twelve hours later, HC was evaluated by bladder wet weight (BWW to quantify edema, Evans blue extravasation (EBE to measure vascular permeability, and macroscopic and microscopic analysis. All bladders were assessed by histopathological analysis RESULTS: rhIL-11 (at 125 and 625 mg attenuated the IFS- induced increase of BWW (37.48% and 45.44%, respectively, p < 0.05 and EBE (62.35% and 56.47%, respectively, p < 0.05. IFS- induced macroscopic edema and hemorrhage and microscopic alterations, were also prevented by rhIL-11 at 625 mg. (p < 0.05 CONCLUSION: Our results demonstrate a protective effect of rhIL-11 on experimental IFS- induced HC, not previously reported.

  16. Construction and characterization of recombinant flaviviruses bearing insertions between E and NS1 genes

    Directory of Open Access Journals (Sweden)

    Kubelka Claire F

    2007-10-01

    Full Text Available Abstract Background The yellow fever virus, a member of the genus Flavivirus, is an arthropod-borne pathogen causing severe disease in humans. The attenuated yellow fever 17D virus strain has been used for human vaccination for 70 years and has several characteristics that are desirable for the development of new, live attenuated vaccines. We described here a methodology to construct a viable, and immunogenic recombinant yellow fever 17D virus expressing a green fluorescent protein variant (EGFP. This approach took into account the presence of functional motifs and amino acid sequence conservation flanking the E and NS1 intergenic region to duplicate and fuse them to the exogenous gene and thereby allow the correct processing of the viral polyprotein precursor. Results YF 17D EGFP recombinant virus was grew in Vero cells and reached a peak titer of approximately 6.45 ± 0.4 log10 PFU/mL at 96 hours post-infection. Immunoprecipitation and confocal laser scanning microscopy demonstrated the expression of the EGFP, which was retained in the endoplasmic reticulum and not secreted from infected cells. The association with the ER compartment did not interfere with YF assembly, since the recombinant virus was fully competent to replicate and exit the cell. This virus was genetically stable up to the tenth serial passage in Vero cells. The recombinant virus was capable to elicit a neutralizing antibody response to YF and antibodies to EGFP as evidenced by an ELISA test. The applicability of this cloning strategy to clone gene foreign sequences in other flavivirus genomes was demonstrated by the construction of a chimeric recombinant YF 17D/DEN4 virus. Conclusion This system is likely to be useful for a broader live attenuated YF 17D virus-based vaccine development for human diseases. Moreover, insertion of foreign genes into the flavivirus genome may also allow in vivo studies on flavivirus cell and tissue tropism as well as cellular processes related

  17. Maximum likelihood estimation of the attenuated ultrasound pulse

    DEFF Research Database (Denmark)

    Rasmussen, Klaus Bolding

    1994-01-01

    The attenuated ultrasound pulse is divided into two parts: a stationary basic pulse and a nonstationary attenuation pulse. A standard ARMA model is used for the basic pulse, and a nonstandard ARMA model is derived for the attenuation pulse. The maximum likelihood estimator of the attenuated...

  18. Production of bioactive soluble interleukin-15 in complex with interleukin-15 receptor alpha from a conditionally-replicating oncolytic HSV-1.

    Directory of Open Access Journals (Sweden)

    David C Gaston

    Full Text Available Oncolytic type-1 herpes simplex viruses (oHSVs lacking the γ134.5 neurovirulence gene are being evaluated for treatment of a variety of malignancies. oHSVs replicate within and directly kill permissive cancer cells. To augment their anti-tumor activity, oHSVs have been engineered to express immunostimulatory molecules, including cytokines, to elicit tumor-specific immune responses. Interleukin-15 (IL-15 holds potential as an immunotherapeutic cytokine because it has been demonstrated to promote both natural killer (NK cell-mediated and CD8(+ T cell-mediated cytotoxicity against cancer cells. The purpose of these studies was to engineer an oHSV producing bioactive IL-15. Two oHSVs were constructed encoding murine (mIL-15 alone (J100 or with the mIL-15 receptor α (mIL-15Rα, J100D to determine whether co-expression of these proteins is required for production of bioactive mIL-15 from oHSV. The following were demonstrated: i both oHSVs retain replication competence and cytotoxicity in permissive tumor cell lines. ii Enhanced production of mIL-15 was detected in cell lysates of neuro-2a cells following J100D infection as compared to J100 infection, suggesting that mIL-15Rα improved mIL-15 production. iii Soluble mIL-15 in complex with mIL-15Rα was detected in supernates from J100D-infected, but not J100-infected, neuro-2a, GL261, and CT-2A cells. These cell lines vary in permissiveness to oHSV replication and cytotoxicity, demonstrating soluble mIL-15/IL-15Rα complex production from J100D was independent of direct oHSV effects. iv The soluble mIL-15/IL-15Rα complex produced by J100D was bioactive, stimulating NK cells to proliferate and reduce the viability of syngeneic GL261 and CT-2A cells. v J100 and J100D were aneurovirulent inasmuch as no neuropathologic effects were documented following direct inoculation into brains of CBA/J mice at up to 1x10(7 plaque forming units. The production of mIL-15/mIL-15Rα from multiple tumor lines, as well

  19. The HDAC Inhibitors Scriptaid and LBH589 Combined with the Oncolytic Virus Delta24-RGD Exert Enhanced Anti-Tumor Efficacy in Patient-Derived Glioblastoma Cells.

    Directory of Open Access Journals (Sweden)

    Lotte M E Berghauser Pont

    Full Text Available A phase I/II trial for glioblastoma with the oncolytic adenovirus Delta24-RGD was recently completed. Delta24-RGD conditionally replicates in cells with a disrupted retinoblastoma-pathway and enters cells via αvβ3/5 integrins. Glioblastomas are differentially sensitive to Delta24-RGD. HDAC inhibitors (HDACi affect integrins and share common cell death pathways with Delta24-RGD. We studied the combination treatment effects of HDACi and Delta24-RGD in patient-derived glioblastoma stem-like cells (GSC, and we determined the most effective HDACi.SAHA, Valproic Acid, Scriptaid, MS275 and LBH589 were combined with Delta24-RGD in fourteen distinct GSCs. Synergy was determined by Chou Talalay method. Viral infection and replication were assessed using luciferase and GFP encoding vectors and hexon-titration assays. Coxsackie adenovirus receptor and αvβ3 integrin levels were determined by flow cytometry. Oncolysis and mechanisms of cell death were studied by viability, caspase-3/7, LDH and LC3B/p62, phospho-p70S6K. Toxicity was studied on normal human astrocytes. MGMT promotor methylation status, TCGA classification, Rb-pathway and integrin gene expression levels were assessed as markers of responsiveness.Scriptaid and LBH589 acted synergistically with Delta24-RGD in approximately 50% of the GSCs. Both drugs moderately increased αvβ3 integrin levels and viral infection in responding but not in non-responding GSCs. LBH589 moderately increased late viral gene expression, however, virus titration revealed diminished viral progeny production by both HDACi, Scriptaid augmented caspase-3/7 activity, LC3B conversion, p62 and phospho-p70S6K consumption, as well as LDH levels. LBH589 increased LDH and phospho-p70S6K consumption. Responsiveness correlated with expression of various Rb-pathway genes and integrins. Combination treatments induced limited toxicity to human astrocytes.LBH589 and Scriptaid combined with Delta24-RGD revealed synergistic anti

  20. Preclinical pharmacology and toxicology study of Ad-hTERT-E1a-Apoptin, a novel dual cancer-specific oncolytic adenovirus

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Yanxin [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Institute of Military Veterinary, Academy of Military Medical Sciences of PLA, Changchun 130122 (China); Guo, Huanhuan [Institute of Military Veterinary, Academy of Military Medical Sciences of PLA, Changchun 130122 (China); Changchun Brother Biotech Co., Ltd., Changchun, 130000 (China); Hu, Ningning; He, Dongyun [Institute of Military Veterinary, Academy of Military Medical Sciences of PLA, Changchun 130122 (China); The Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun 130122 (China); Zhang, Shi [Institute of Military Veterinary, Academy of Military Medical Sciences of PLA, Changchun 130122 (China); School of Clinical Medicine, Jilin University, Changchun 130001 (China); Chu, Yunjie [Affiliated Hospital of Changchun University of Traditional Chinese Medicine, Changchun 130021 (China); Huang, Yubin [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Li, Xiao, E-mail: lixiao06@mails.jlu.edu.cn [Institute of Military Veterinary, Academy of Military Medical Sciences of PLA, Changchun 130122 (China); The Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun 130122 (China); Sun, LiLi, E-mail: linjiaxiaoya@163.com [Department of Head and Neck Surgery, Tumor Hospital of Jilin Province, Changchun 130012 (China); Jin, Ningyi, E-mail: ningyij@126.com [Institute of Military Veterinary, Academy of Military Medical Sciences of PLA, Changchun 130122 (China); The Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun 130122 (China)

    2014-10-15

    Clinical studies have demonstrated that conditionally replicating adenovirus is safe. We constructed an oncolytic adenovirus, Ad-hTERT-E1a-Apoptin, using a cancer-specific promoter (human telomerase reverse transcriptase promoter, hTERTp) and a cancer cell-selective apoptosis-inducing gene (Apoptin). Ad-hTERT-E1a-Apoptin was proven effective both in vitro and in vivo in our previous study. In this study, the preclinical safety profiles of Ad-hTERT-E1a-Apoptin in animal models were investigated. At doses of 5.0 × 10{sup 8}, 2.5 × 10{sup 9}, and 1.25 × 10{sup 10} viral particles (VP)/kg, Ad-hTERT-E1a-Apoptin had no adverse effects on mouse behavior, muscle cooperation, sedative effect, digestive system, and nervous systems, or on beagle cardiovascular and respiratory systems at 5.0 × 10{sup 8}, 2.5 × 10{sup 9}, and 1.25 × 10{sup 10} VP/kg doses. In acute toxicity tests in mice, the maximum tolerated dose > 5 × 10{sup 10} VP/kg. There was no inflammation or ulceration at the injection sites within two weeks. In repeat-dose toxicological studies, the no observable adverse effect levels of Ad-hTERT-E1a-Apoptin in rats (1.25 × 10{sup 10} VP/kg) and beagles (2.5 × 10{sup 9} VP/kg) were 62.5- and 12.5-fold of the proposed clinical dose, respectively. The anti-virus antibody was produced in animal sera. Bone marrow examination revealed no histopathological changes. Guinea pigs sensitized by three repeated intraperitoneal injections of 1.35 × 10{sup 10} VP/mL Ad-hTERT-E1a-Apoptin each and challenged by one intravenous injection of 1.67 × 10{sup 8} VP/kg Ad-hTERT-E1a-Apoptin did not exhibit any sign of systemic anaphylaxis. Our data from different animal models suggest that Ad-hTERT-E1a-Apoptin is a safe anti-tumor therapeutic agent. - Highlights: • We use the rodents and non-rodents animal models to evaluation Ad-hTERT-E1a-Apoptin. • Ad-hTERT-E1a-Apoptin is a safe anti-tumor therapeutic agent. • Demonstrate the safety and feasibility dose of injected Ad

  1. Identifying the important HIV-1 recombination breakpoints.

    Directory of Open Access Journals (Sweden)

    John Archer

    Full Text Available Recombinant HIV-1 genomes contribute significantly to the diversity of variants within the HIV/AIDS pandemic. It is assumed that some of these mosaic genomes may have novel properties that have led to their prevalence, particularly in the case of the circulating recombinant forms (CRFs. In regions of the HIV-1 genome where recombination has a tendency to convey a selective advantage to the virus, we predict that the distribution of breakpoints--the identifiable boundaries that delimit the mosaic structure--will deviate from the underlying null distribution. To test this hypothesis, we generate a probabilistic model of HIV-1 copy-choice recombination and compare the predicted breakpoint distribution to the distribution from the HIV/AIDS pandemic. Across much of the HIV-1 genome, we find that the observed frequencies of inter-subtype recombination are predicted accurately by our model. This observation strongly indicates that in these regions a probabilistic model, dependent on local sequence identity, is sufficient to explain breakpoint locations. In regions where there is a significant over- (either side of the env gene or under- (short regions within gag, pol, and most of env representation of breakpoints, we infer natural selection to be influencing the recombination pattern. The paucity of recombination breakpoints within most of the envelope gene indicates that recombinants generated in this region are less likely to be successful. The breakpoints at a higher frequency than predicted by our model are approximately at either side of env, indicating increased selection for these recombinants as a consequence of this region, or at least part of it, having a tendency to be recombined as an entire unit. Our findings thus provide the first clear indication of the existence of a specific portion of the genome that deviates from a probabilistic null model for recombination. This suggests that, despite the wide diversity of recombinant forms seen in

  2. Identifying the Important HIV-1 Recombination Breakpoints

    Science.gov (United States)

    Fan, Jun; Simon-Loriere, Etienne; Arts, Eric J.; Negroni, Matteo; Robertson, David L.

    2008-01-01

    Recombinant HIV-1 genomes contribute significantly to the diversity of variants within the HIV/AIDS pandemic. It is assumed that some of these mosaic genomes may have novel properties that have led to their prevalence, particularly in the case of the circulating recombinant forms (CRFs). In regions of the HIV-1 genome where recombination has a tendency to convey a selective advantage to the virus, we predict that the distribution of breakpoints—the identifiable boundaries that delimit the mosaic structure—will deviate from the underlying null distribution. To test this hypothesis, we generate a probabilistic model of HIV-1 copy-choice recombination and compare the predicted breakpoint distribution to the distribution from the HIV/AIDS pandemic. Across much of the HIV-1 genome, we find that the observed frequencies of inter-subtype recombination are predicted accurately by our model. This observation strongly indicates that in these regions a probabilistic model, dependent on local sequence identity, is sufficient to explain breakpoint locations. In regions where there is a significant over- (either side of the env gene) or under- (short regions within gag, pol, and most of env) representation of breakpoints, we infer natural selection to be influencing the recombination pattern. The paucity of recombination breakpoints within most of the envelope gene indicates that recombinants generated in this region are less likely to be successful. The breakpoints at a higher frequency than predicted by our model are approximately at either side of env, indicating increased selection for these recombinants as a consequence of this region, or at least part of it, having a tendency to be recombined as an entire unit. Our findings thus provide the first clear indication of the existence of a specific portion of the genome that deviates from a probabilistic null model for recombination. This suggests that, despite the wide diversity of recombinant forms seen in the viral

  3. Comparison of non-attenuation corrected and attenuation corrected myocardial perfusion SPE

    Directory of Open Access Journals (Sweden)

    Hasan Raza

    2016-09-01

    Conclusion: This study demonstrates that CT based attenuation corrected Tc-99mm sestamibi SPECT myocardial perfusion imaging significantly improved the specificity of the RCA territory compared with non-attenuation corrected Tc-99mm sestamibi SPECT myocardial perfusion imaging in both genders irrespective of BMI.

  4. Attenuation tomography in West Bohemia/Vogtland

    Science.gov (United States)

    Mousavi, Sima; Haberland, Christian; Bauer, Klaus; Hejrani, Babak; Korn, Michael

    2017-01-01

    We present a three-dimensional (3-D) P-wave attenuation (Qp) model for the geodynamically active swarm earthquake area of West Bohemia/Vogtland in the Czech/German border region. Path-averaged attenuation t* is calculated from amplitude spectra of time windows around the P-wave arrivals of local earthquakes. Average t/t* value or Qp for stations close to Nový Kostel are very low (focal zone (increases up to 500 within 80 km distance). The SIMUL2000 tomography scheme is used to invert the t* for P-wave attenuation perturbation. Analysis of resolution shows that our model is well-resolved in the vicinity of earthquake swarm hypocenters. The prominent features of the model are located around Nový Kostel focal zone and its northern vicinity. Beneath Nový Kostel a vertically stretched (down to depth of 11 km) and a highly attenuating body is observed. We believe that this is due to fracturing and high density of cracks inside the weak earthquake swarm zone in conjunction with presence of free gas/fluid. Further north of Nový Kostel two highly attenuating bodies are imaged which could represent fluid channels toward the surface. The eastern anomaly shows a good correlation with the fluid accumulation area which was suggested in 9HR seismic profile.

  5. Implications of recombination for HIV diversity.

    Science.gov (United States)

    Ramirez, Bertha Cecilia; Simon-Loriere, Etienne; Galetto, Roman; Negroni, Matteo

    2008-06-01

    The human immunodeficiency virus (HIV) population is characterised by extensive genetic variability that results from high error and recombination rates of the reverse transcription process, and from the fast turnover of virions in HIV-infected individuals. Among the viral variants encountered at the global scale, recombinant forms are extremely abundant. Some of these recombinants (known as circulating recombinant forms) become fixed and undergo rapid expansion in the population. The reasons underlying their epidemiological success remain at present poorly understood and constitute a fascinating area for future research to improve our understanding of immune escape, pathogenicity and transmission. Recombinant viruses are generated during reverse transcription as a consequence of template switching between the two genetically different genomic RNAs present in a heterozygous virus. Recombination can thereby generate shortcuts in evolution by producing mosaic reverse transcription products of parental genomes. Therefore, in a single infectious cycle multiple mutations that are positively selected can be combined or, conversely, negatively selected mutations can be removed. Recombination is therefore involved in different aspects of HIV evolution, adaptation to its host, and escape from antiviral treatments.

  6. Initiation of meiotic recombination in Ustilago maydis.

    Science.gov (United States)

    Kojic, Milorad; Sutherland, Jeanette H; Pérez-Martín, José; Holloman, William K

    2013-12-01

    A central feature of meiosis is the pairing and recombination of homologous chromosomes. Ustilago maydis, a biotrophic fungus that parasitizes maize, has long been utilized as an experimental system for studying recombination, but it has not been clear when in the life cycle meiotic recombination initiates. U. maydis forms dormant diploid teliospores as the end product of the infection process. Upon germination, teliospores complete meiosis to produce four haploid basidiospores. Here we asked whether the meiotic process begins when teliospores germinate or at an earlier stage in development. When teliospores homozygous for a cdc45 mutation temperature sensitive for DNA synthesis were germinated at the restrictive temperature, four nuclei became visible. This implies that teliospores have already undergone premeiotic DNA synthesis and suggests that meiotic recombination initiates at a stage of infection before teliospores mature. Determination of homologous recombination in plant tissue infected with U. maydis strains heteroallelic for the nar1 gene revealed that Nar(+) recombinants were produced at a stage before teliospore maturation. Teliospores obtained from a spo11Δ cross were still able to germinate but the process was highly disturbed and the meiotic products were imbalanced in chromosomal complement. These results show that in U. maydis, homologous recombination initiates during the infection process and that meiosis can proceed even in the absence of Spo11, but with loss of genomic integrity.

  7. Optimal Expression Condition of Recombinant RAP

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jie; ZHANG Hong; BI Hao; LIU Zhiguo; GUO Jianli; QU Shen

    2007-01-01

    In order to construct the expression recombinant of human receptor associated protein (RAP), optimize its expression condition and obtain the recombinant protein after expression with high efficiency, two prokaryotic expression vectors-pT7-PL and pET-28a(+) were used to construct the expression recombinant containing RAP cDNA, and the expression efficiency of two kinds of expression E. coli of BL21 strains was compared. The effect of different induction conditions on the expression of recombinant RAP was observed. After recombinant protein was purified with Ni+-nitrilotriacetic acid (Ni+-NTA) affinity chromatogram, its binding ability with microphage was observed. The results showed that two recombinant plasmids both obtained high expression of RAP. The expression levels of RAP in plasmid pT7-PL-RAP in BL21 (DE3, plysS) strain were significantly higher than in BL21 (DE3) strain. The expression of pT7-PL-RAP in the presence of chloramphenicol was higher than in the absence of chloramphenicol, and most of the inducible expressed RAP was soluble. The RAP which was purified by Ni+-NTA resin could strongly bind with the RAW264.7 cells rich in low density lipoprotein receptor (LDLR) family receptors. It was concluded that the expression condition of recombinant RAP was optimized and functional RAP was obtained, which offered a good foundation for the further production of RAP as research tool.

  8. Recombination analysis of Soybean mosaic virus sequences reveals evidence of RNA recombination between distinct pathotypes

    Directory of Open Access Journals (Sweden)

    Babu Mohan

    2008-11-01

    Full Text Available Abstract RNA recombination is one of the two major factors that create RNA genome variability. Assessing its incidence in plant RNA viruses helps understand the formation of new isolates and evaluate the effectiveness of crop protection strategies. To search for recombination in Soybean mosaic virus (SMV, the causal agent of a worldwide seed-borne, aphid-transmitted viral soybean disease, we obtained all full-length genome sequences of SMV as well as partial sequences encoding the N-terminal most (P1 protease and the C-terminal most (capsid protein; CP viral protein. The sequences were analyzed for possible recombination events using a variety of automatic and manual recombination detection and verification approaches. Automatic scanning identified 3, 10, and 17 recombination sites in the P1, CP, and full-length sequences, respectively. Manual analyses confirmed 10 recombination sites in three full-length SMV sequences. To our knowledge, this is the first report of recombination between distinct SMV pathotypes. These data imply that different SMV pathotypes can simultaneously infect a host cell and exchange genetic materials through recombination. The high incidence of SMV recombination suggests that recombination plays an important role in SMV evolution. Obtaining additional full-length sequences will help elucidate this role.

  9. Homologous recombination in Leishmania enriettii.

    Science.gov (United States)

    Tobin, J F; Laban, A; Wirth, D F

    1991-02-01

    We have used derivatives of the recently developed stable transfection vector pALT-Neo to formally demonstrate that Leishmania enriettii contains the enzymatic machinery necessary for homologous recombination. This observation has implications for gene regulation, gene amplification, genetic diversity, and the maintenance of tandemly repeated gene families in the Leishmania genome as well as in closely related organisms, including Trypanosoma brucei. Two plasmids containing nonoverlapping deletions of the chloramphenicol acetyltransferase (CAT) gene, as well as the neomycin-resistance gene, were cotransfected into L. enriettii. Analysis of the DNA from these cells by Southern blotting and plasmid rescue revealed that a full-length or doubly deleted CAT gene could be reconstructed by homologous crossing-over and/or gene conversion between the two deletion plasmids. Additionally, parasites cotransfected with pALT-Neo and pALT-CAT-S, a plasmid containing two copies of the chimeric alpha-tubulin-CAT gene, resulted in G418-resistant parasites expressing high levels of CAT activity. The structure of the DNA within these cells, as shown by Southern blot analysis and the polymerase chain reaction, is that which would be expected from a homologous exchange event occurring between the two plasmids.

  10. Recombinant horseradish peroxidase: production and analytical applications.

    Science.gov (United States)

    Grigorenko, V G; Andreeva, I P; Rubtsova, M Yu; Egorov, A M

    2015-04-01

    Horseradish peroxidase is a key enzyme in bio- and immunochemical analysis. New approaches in functional expression of the peroxidase gene in E. coli cells and the subsequent refolding of the resulting protein yield a recombinant enzyme that is comparable in its spectral and catalytic characteristics to the native plant peroxidase. Genetic engineering approaches allow production of recombinant peroxidase conjugates with both protein antigens and Fab antibody fragments. The present article reviews the use of recombinant horseradish peroxidase as the marker enzyme in ELISA procedures as well as in amperometric sensors based on direct electron transfer.

  11. Advances in recombinant antibody manufacturing.

    Science.gov (United States)

    Kunert, Renate; Reinhart, David

    2016-04-01

    Since the first use of Chinese hamster ovary (CHO) cells for recombinant protein expression, production processes have steadily improved through numerous advances. In this review, we have highlighted several key milestones that have contributed to the success of CHO cells from the beginning of their use for monoclonal antibody (mAb) expression until today. The main factors influencing the yield of a production process are the time to accumulate a desired amount of biomass, the process duration, and the specific productivity. By comparing maximum cell densities and specific growth rates of various expression systems, we have emphasized the limiting parameters of different cellular systems and comprehensively described scientific approaches and techniques to improve host cell lines. Besides the quantitative evaluation of current systems, the quality-determining properties of a host cell line, namely post-translational modifications, were analyzed and compared to naturally occurring polyclonal immunoglobulin fractions from human plasma. In summary, numerous different expression systems for mAbs are available and also under scientific investigation. However, CHO cells are the most frequently investigated cell lines and remain the workhorse for mAb production until today.

  12. Polynomial identities for ternary intermolecular recombination

    CERN Document Server

    Bremner, Murray R

    2010-01-01

    The operation of binary intermolecular recombination, originating in the theory of DNA computing, permits a natural generalization to n-ary operations which perform simultaneous recombination of n molecules. In the case n = 3, we use computer algebra to determine the polynomial identities of degree <= 9 satisfied by this trilinear nonassociative operation. Our approach requires computing a basis for the nullspace of a large integer matrix, and for this we compare two methods: (i) the row canonical form, and (ii) the Hermite normal form with lattice basis reduction. In the conclusion, we formulate some conjectures for the general case of n-ary intermolecular recombination.

  13. Live attenuated vaccines for invasive Salmonella infections.

    Science.gov (United States)

    Tennant, Sharon M; Levine, Myron M

    2015-06-19

    Salmonella enterica serovar Typhi produces significant morbidity and mortality worldwide despite the fact that there are licensed Salmonella Typhi vaccines available. This is primarily due to the fact that these vaccines are not used in the countries that most need them. There is growing recognition that an effective invasive Salmonella vaccine formulation must also prevent infection due to other Salmonella serovars. We anticipate that a multivalent vaccine that targets the following serovars will be needed to control invasive Salmonella infections worldwide: Salmonella Typhi, Salmonella Paratyphi A, Salmonella Paratyphi B (currently uncommon but may become dominant again), Salmonella Typhimurium, Salmonella Enteritidis and Salmonella Choleraesuis (as well as other Group C Salmonella). Live attenuated vaccines are an attractive vaccine formulation for use in developing as well as developed countries. Here, we describe the methods of attenuation that have been used to date to create live attenuated Salmonella vaccines and provide an update on the progress that has been made on these vaccines.

  14. Research on Nanosecond Pulse Corona Discharge Attenuation

    Institute of Scientific and Technical Information of China (English)

    HE Zheng-hao; XU Huai-li; BAI Jing; YU Fu-sheng; HU Feng; LI Jin

    2007-01-01

    A line-to-plate reactor was set-up in the experimental study on the application of nanosecond pulsed corona discharge plasma technology in environmental pollution control.Investigation on the attenuation and distortion of the amplitude of the pulse wave front and the discharge image as well as the waveform along the corona wire was conducted.The results show that the wave front decreases sharply during the corona discharge along the corona wire.The higher the amplitude of the applied pulse is,the more the amplitude of the wave front decreased.The wave attenuation responds in a lower corona discharge inversely.To get a higher efficiency of the line-to-plate reactor a sharp attenuation of the corona has to be considered in practical design.

  15. Oral attenuated Salmonella typhimurium vaccine against MG7-Ag mimotope of gastric cancer

    Institute of Scientific and Technical Information of China (English)

    Fan-Ping Meng; Jie Ding; Zhao-Cai Yu; Quan-Li Han; Chang-Cun Guo; Na Liu; Dai-Ming Fan

    2005-01-01

    AIM: To develop an oral attenuated Salmonella typhimurium vaccine against gastric cancer and to evaluate its efficacy in mice.METHODS: A complementary sequence of Nco I site and a sequence coding for MG7-Ag mimotope were designed at the 5' terminus of forward primer. Using p1.2 Ⅱ-HBCAg plasmid as template, PCR was performed to get a fusion gene of the mimotope and a HBcAg gene. The fusion gene was then subcloned into the plasmid pYA3341complementary to Salmonella typhimurium X4550, and the recombinant plasmid was then transformed into attenuated Salmonella typhimurium X4550. Balb/c mice were orally immunized with the recombinant Salmonella typhimurium X4550. The mice were immunized every 2 wk to reinforce the immunity. At the 6th wk, serum titer of antibody was detected by ELISA, and at the 8th wk,cellular immunity was detected by 51Cr release test. Ehrlich ascites carcinoma cells expressing MG7-Ag were used in tumor challenge assay as a model to evaluate the protective effect of the vaccine.RESULTS: Serum titer of antibody against MG7-Ag was significantly higher in mice immunized with the vaccine than in control groups (0.9538±0.043 vs0.6531±0.018,P<0.01; 0.9538±0.043 vs0.6915±0.012, P<0.01), while in vitro 51Cr release assay of the splenocytes showed no statistical difference in the three groups. Two weeks after tumor challenge, 1 in 5 immunized mice was tumor free, while all the mice in the control group presented tumor.CONCLUSION: Oral attenuated Salmonella typhimurium vaccine against the MG7-Ag mimotope of gastric cancer is immunogenic. It can induce significant humoral immunity against tumors in mice, and has some protective effects.

  16. Is there seismic attenuation in the mantle?

    Science.gov (United States)

    Ricard, Y.; Durand, S.; Montagner, J.-P.; Chambat, F.

    2014-02-01

    The small scale heterogeneity of the mantle is mostly due to the mixing of petrological heterogeneities by a smooth but chaotic convection and should consist in a laminated structure (marble cake) with a power spectrum S(k) varying as 1/k, where k is the wavenumber of the anomalies. This distribution of heterogeneities during convective stirring with negligible diffusion, called Batchelor regime is documented by fluid dynamic experiments and corresponds to what can be inferred from geochemistry and seismic tomography. This laminated structure imposes density, seismic velocity and potentially, anisotropic heterogeneities with similar 1/k spectra. A seismic wave of wavenumber k0 crossing such a medium is partly reflected by the heterogeneities and we show that the scattered energy is proportional to k0S(2k0). The reduction of energy for the propagating wave appears therefore equivalent to a quality factor 1/Q∝k0S(2k0). With the specific 1/k spectrum of the mantle, the resulting apparent attenuation should therefore be frequency independent. We show that the total contribution of 6-9% RMS density, velocity and anisotropy would explain the observed S and P attenuation of the mantle. Although these values are large, they are not unreasonable and we discuss how they depend on the range of frequencies over which the attenuation is explained. If such a level of heterogeneity were present, most of the attenuation of the Earth would be due to small scale scattering by laminations, not by intrinsic dissipation. Intrinsic dissipation must certainly exist but might correspond to a larger, yet unobserved Q. This provocative result would explain the very weak frequency dependence of the attenuation, and the fact that bulk attenuation seems negligible, two observations that have been difficult to explain for 50 years.

  17. Resistance to Oncolytic Myxoma Virus Therapy in Nf1−/−/Trp53−/− Syngeneic Mouse Glioma Models Is Independent of Anti-Viral Type-I Interferon

    Science.gov (United States)

    Zemp, Franz J.; McKenzie, Brienne A.; Lun, Xueqing; Maxwell, Lori; Reilly, Karlyne M.; McFadden, Grant; Yong, V. Wee; Forsyth, Peter A.

    2013-01-01

    Despite promising preclinical studies, oncolytic viral therapy for malignant gliomas has resulted in variable, but underwhelming results in clinical evaluations. Of concern are the low levels of tumour infection and viral replication within the tumour. This discrepancy between the laboratory and the clinic could result from the disparity of xenograft versus syngeneic models in determining in vivo viral infection, replication and treatment efficacy. Here we describe a panel of primary mouse glioma lines derived from Nf1+/−Trp53+/− mice in the C57Bl/6J background for use in the preclinical testing of the oncolytic virus Myxoma (MYXV). These lines show a range of susceptibility to MYXV replication in vitro, but all succumb to viral-mediated cell death. Two of these lines orthotopically grafted produced aggressive gliomas. Intracranial injection of MYXV failed to result in sustained viral replication or treatment efficacy, with minimal tumour infection that was completely resolved by 7 days post-infection. We hypothesized that the stromal production of Type-I interferons (IFNα/β) could explain the resistance seen in these models; however, we found that neither the cell lines in vitro nor the tumours in vivo produce any IFNα/β in response to MYXV infection. To confirm IFNα/β did not play a role in this resistance, we ablated the ability of tumours to respond to IFNα/β via IRF9 knockdown, and generated identical results. Our studies demonstrate that these syngeneic cell lines are relevant preclinical models for testing experimental glioma treatments, and show that IFNα/β is not responsible for the MYXV treatment resistance seen in syngeneic glioma models. PMID:23762429

  18. Recombinant Human Papillomavirus (HPV) Bivalent Vaccine

    Science.gov (United States)

    This page contains brief information about recombinant human papillomavirus (HPV) bivalent vaccine and a collection of links to more information about the use of this vaccine, research results, and ongoing clinical trials.

  19. Recombinant Human Papillomavirus (HPV) Nonavalent Vaccine

    Science.gov (United States)

    This page contains brief information about recombinant human papillomavirus (HPV) nonavalent vaccine and a collection of links to more information about the use of this vaccine, research results, and ongoing clinical trials.

  20. Recombinant Human Papillomavirus (HPV) Quadrivalent Vaccine

    Science.gov (United States)

    This page contains brief information about recombinant human papillomavirus (HPV) quadrivalent vaccine and a collection of links to more information about the use of this vaccine, research results, and ongoing clinical trials.

  1. The homologous recombination system of Ustilago maydis.

    Science.gov (United States)

    Holloman, William K; Schirawski, Jan; Holliday, Robin

    2008-08-01

    Homologous recombination is a high fidelity, template-dependent process that is used in repair of damaged DNA, recovery of broken replication forks, and disjunction of homologous chromosomes in meiosis. Much of what is known about recombination genes and mechanisms comes from studies on baker's yeast. Ustilago maydis, a basidiomycete fungus, is distant evolutionarily from baker's yeast and so offers the possibility of gaining insight into recombination from an alternative perspective. Here we have surveyed the genome of U. maydis to determine the composition of its homologous recombination system. Compared to baker's yeast, there are fundamental differences in the function as well as in the repertoire of dedicated components. These include the use of a BRCA2 homolog and its modifier Dss1 rather than Rad52 as a mediator of Rad51, the presence of only a single Rad51 paralog, and the absence of Dmc1 and auxiliary meiotic proteins.

  2. Recombinant allergens: what does the future hold?

    Science.gov (United States)

    Valenta, Rudolf; Niespodziana, Katarzyna; Focke-Tejkl, Margit; Marth, Katharina; Huber, Hans; Neubauer, Angela; Niederberger, Verena

    2011-04-01

    This year we are celebrating not only the centenary of allergen-specific immunotherapy but also the 10-year anniversary of the first administration of recombinant allergen-based vaccines to allergic patients. By using recombinant DNA technology, defined and safe allergy vaccines can be produced that allow us to overcome many, if not all, of the problems associated with the use of natural allergen extracts, such as insufficient quality, allergenic activity, and poor immunogenicity. Here we provide an update of clinical studies with recombinant allergen-based vaccines, showing that some of these vaccines have undergone successful clinical evaluation up to phase III studies. Furthermore, we introduce a strategy for allergen-specific immunotherapy based on recombinant fusion proteins consisting of viral carrier proteins and allergen-derived peptides without allergenic activity, which holds the promise of being free of side effects and eventually being useful for prophylactic vaccination.

  3. Recombination Effects on Supernovae Light-Curves

    CERN Document Server

    Goldfriend, Tomer; Sari, Re'em

    2014-01-01

    Supernovae of type IIP are marked by the long plateau seen in their optical light curves. The plateau is believed to be the result of a recombination wave that propagates through the outflowing massive hydrogen envelope. Here, we analytically investigate the transition from a fully ionized envelope to a partially recombined one and its effects on the SN light curve. The motivation is to establish the underlying processes which dominate the evolution at late times when recombination takes place in the envelope, yet early enough so that $^{56}$Ni decay is a negligible source of energy. We assume a simple, yet adequate, hydrodynamic profile of the envelope and study the mechanisms which dominate the energy emission and the observed temperature. We consider the diffusion of photons through the envelope while analyzing the ionization fraction and the coupling between radiation and gas. We find that once recombination starts, the observed temperature decreases slowly in time. However, in a typical red supergiant (R...

  4. Genetic Analyses of Meiotic Recombination in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Meiosis is essential for sexual reproduction and recombination is a critical step required for normal meiosis. Understanding the underlying molecular mechanisms that regulate recombination ie important for medical, agricultural and ecological reasons. Readily available molecular and cytological tools make Arabidopsis an excellent system to study meiosis. Here we review recent developments in molecular genetic analyses on meiotic recombination. These Include studies on plant homologs of yeast and animal genes, as well as novel genes that were first identified in plants. The characterizations of these genes have demonstrated essential functions from the initiation of recombination by double-strand breaks to repair of such breaks, from the formation of double-Holliday junctions to possible resolution of these junctions, both of which are critical for crossover formation. The recent advances have ushered a new era in plant meiosis, in which the combination of genetics, genomics, and molecular cytology can uncover important gene functions.

  5. The stability of recombined milk fat globules.

    NARCIS (Netherlands)

    Melsen, J.P.

    1987-01-01

    The stability of the fat globules in recombined milk products against creaming, flocculation, clustering, partial coalescence and real coalescence, with the emphasis on partial coalescence, was studied. (partial) Coalescence was characterized by determining changes in globule size distribution and f

  6. Complexity through Recombination: From Chemistry to Biology

    Directory of Open Access Journals (Sweden)

    Carolina Díaz Arenas

    2010-12-01

    Full Text Available Recombination is a common event in nature, with examples in physics, chemistry, and biology. This process is characterized by the spontaneous reorganization of structural units to form new entities. Upon reorganization, the complexity of the overall system can change. In particular the components of the system can now experience a new response to externally applied selection criteria, such that the evolutionary trajectory of the system is altered. In this work we explore the link between chemical and biological forms of recombination. We estimate how the net system complexity changes, through analysis of RNA-RNA recombination and by mathematical modeling. Our results underscore the importance of recombination in the origins of life on the Earth and its subsequent evolutionary divergence.

  7. Ultrasound transmission attenuation tomography using energy-scaled amplitude ratios

    Science.gov (United States)

    Chen, Ting; Shin, Junseob; Huang, Lianjie

    2016-04-01

    Ultrasound attenuation of breast tumors is related to their types and pathological states, and can be used to detect and characterize breast cancer. Particularly, ultrasound scattering attenuation can infer the margin properties of breast tumors. Ultrasound attenuation tomography quantitatively reconstructs the attenuation properties of the breast. Our synthetic-aperture breast ultrasound tomography system with two parallel transducer arrays records both ultrasound reflection and transmission signals. We develop an ultrasound attenuation tomography method using ultrasound energy-scaled amplitude decays of ultrasound transmission signals and conduct ultrasound attenuation tomography using a known sound-speed model. We apply our ultrasound transmission attenuation tomography method to a breast phantom dataset, and compare the ultrasound attenuation tomography results with conventional beamforming ultrasound images obtained using reflection signals. We show that ultrasound transmission attenuation tomography complements beamforming images in identifying breast lesions.

  8. Recombinant bispecific antibodies for cancer therapy

    Institute of Scientific and Technical Information of China (English)

    Roland E KONTERMANN

    2005-01-01

    Bispecific antibodies can serve as mediators to retarget effector mechanisms to disease-associated sites. Studies over the past two decades have revealed the potentials but also the limitations of conventional bispecific antibodies. The development of recombinant antibody formats has opened up the possibility of generating bispecific molecules with improved properties. This review summarizes recent developments in the field of recombinant bispecific antibodies and discusses further requirements for clinical development.

  9. Hadron Correlations from Recombination and Fragmentation

    CERN Document Server

    Fries, R J

    2005-01-01

    We review the formalism of quark recombination applied to the hadronization of a quark gluon plasma. Evidence in favor of the quark recombination model is outlined. Recent work on parton correlations, leading to detectable correlations between hadrons, is discussed. Hot spots from completely quenched jets are a likely source of such correlations which appear to be jet-like. It will be discussed how such a picture compares with measurement of associated hadron yields at RHIC.

  10. Rapid host adaptation by extensive recombination

    OpenAIRE

    2009-01-01

    Experimental investigations into virus recombination can provide valuable insights into the biochemical mechanisms and the evolutionary value of this fundamental biological process. Here, we describe an experimental scheme for studying recombination that should be applicable to any recombinogenic viruses amenable to the production of synthetic infectious genomes. Our approach is based on differences in fitness that generally exist between synthetic chimaeric genomes and the wild-type viruses ...

  11. Oral immunization with recombinant listeria monocytogenes controls virus load after vaginal challenge with feline immunodeficiency virus.

    Science.gov (United States)

    Stevens, Rosemary; Howard, Kristina E; Nordone, Sushila; Burkhard, MaryJo; Dean, Gregg A

    2004-08-01

    Recombinant Listeria monocytogenes has many attractive characteristics as a vaccine vector against human immunodeficiency virus (HIV). Wild-type and attenuated Listeria strains expressing HIV Gag have been shown to induce long-lived mucosal and systemic T-cell responses in mice. Using the feline immunodeficiency virus (FIV) model of HIV we evaluated recombinant L. monocytogenes in a challenge system. Five cats were immunized with recombinant L. monocytogenes that expresses the FIV Gag and delivers an FIV Env-expressing DNA vaccine (LMgag/pND14-Lc-env). Control cats were either sham immunized or immunized with wild-type L. monocytogenes (LM-wt). At 1 year after vaginal challenge, provirus could not be detected in any of the nine tissues evaluated from cats immunized with the recombinant bacteria but was detected in at least one tissue in 8 of 10 control animals. Virus was isolated from bone marrow of four of five LMgag/pND14-Lc-env-immunized cats by use of a stringent coculture system but required CD8(+) T-cell depletion, indicating CD8(+) T-cell suppression of virus replication. Control animals had an inverted CD4:CD8 ratio in mesenteric lymph node and were depleted of both CD4(+) and CD8(+) intestinal epithelial T cells, while LMgag/pND14-Lc-env-immunized animals showed no such abnormalities. Vaginal FIV-specific immunoglobulin A was present at high titer in three LMgag/pND14-Lc-env-immunized cats before challenge and in all five at 1 year postchallenge. This study demonstrates that recombinant L. monocytogenes conferred some control of viral load after vaginal challenge with FIV.

  12. Dissociation of recombinant prion autocatalysis from infectivity.

    Science.gov (United States)

    Noble, Geoffrey P; Supattapone, Surachai

    2015-01-01

    Within the mammalian prion field, the existence of recombinant prion protein (PrP) conformers with self-replicating (ie. autocatalytic) activity in vitro but little to no infectious activity in vivo challenges a key prediction of the protein-only hypothesis of prion replication--that autocatalytic PrP conformers should be infectious. To understand this dissociation of autocatalysis from infectivity, we recently performed a structural and functional comparison between a highly infectious and non-infectious pair of autocatalytic recombinant PrP conformers derived from the same initial prion strain. (1) We identified restricted, C-terminal structural differences between these 2 conformers and provided evidence that these relatively subtle differences prevent the non-infectious conformer from templating the conversion of native PrP(C) substrates containing a glycosylphosphatidylinositol (GPI) anchor. (1) In this article we discuss a model, consistent with these findings, in which recombinant PrP, lacking post-translational modifications and associated folding constraints, is capable of adopting a wide variety of autocatalytic conformations. Only a subset of these recombinant conformers can be adopted by post-translationally modified native PrP(C), and this subset represents the recombinant conformers with high specific infectivity. We examine this model's implications for the generation of highly infectious recombinant prions and the protein-only hypothesis of prion replication.

  13. Recombination rate predicts inversion size in Diptera.

    Science.gov (United States)

    Cáceres, M; Barbadilla, A; Ruiz, A

    1999-09-01

    Most species of the Drosophila genus and other Diptera are polymorphic for paracentric inversions. A common observation is that successful inversions are of intermediate size. We test here the hypothesis that the selected property is the recombination length of inversions, not their physical length. If so, physical length of successful inversions should be negatively correlated with recombination rate across species. This prediction was tested by a comprehensive statistical analysis of inversion size and recombination map length in 12 Diptera species for which appropriate data are available. We found that (1) there is a wide variation in recombination map length among species; (2) physical length of successful inversions varies greatly among species and is inversely correlated with the species recombination map length; and (3) neither the among-species variation in inversion length nor the correlation are observed in unsuccessful inversions. The clear differences between successful and unsuccessful inversions point to natural selection as the most likely explanation for our results. Presumably the selective advantage of an inversion increases with its length, but so does its detrimental effect on fertility due to double crossovers. Our analysis provides the strongest and most extensive evidence in favor of the notion that the adaptive value of inversions stems from their effect on recombination.

  14. The key role of rubella virus glycoproteins in the formation of immune response, and perspectives on their use in the development of new recombinant vaccines.

    Science.gov (United States)

    Petrova, Ekaterina K; Dmitrieva, Anastasia A; Trifonova, Ekaterina A; Nikitin, Nikolai A; Karpova, Olga V

    2016-02-17

    Rubella is a highly contagious viral disease which is mostly threatens to women of reproductive age. Existent live attenuated vaccines are effective enough, but have some drawbacks and are unusable for a certain group of people, including pregnant women and people with AIDS and other immunodeficiency. Thereby the development of alternative non-replicating, recombinant vaccines undoubtedly is needed. This review discusses the protein E1 and E2 role in formation of immune response and perspectives in development of new generation recombinant vaccines using them.

  15. Touch Attenuates Infants' Physiological Reactivity to Stress

    Science.gov (United States)

    Feldman, Ruth; Singer, Magi; Zagoory, Orna

    2010-01-01

    Animal studies demonstrate that maternal touch and contact regulate infant stress, and handling during periods of maternal deprivation attenuates the stress response. To measure the effects of touch on infant stress reactivity during simulated maternal deprivation, 53 dyads were tested in two paradigms: still-face (SF) and still-face with maternal…

  16. Microwave attenuation with composite of copper microwires

    Energy Technology Data Exchange (ETDEWEB)

    Gorriti, A.G.; Marin, P. [Instituto de Magnetismo Aplicado, (UCM-ADIF-CSIC) and Departamento de Fisica de Materiales (UCM). P.O. Box 155, Las Rozas, Madrid 28230 (Spain); Cortina, D. [Micromag S.L., Las Rozas, Madrid 28230 (Spain); Hernando, A., E-mail: antonio.hernando@adif.e [Instituto de Magnetismo Aplicado, (UCM-ADIF-CSIC) and Departamento de Fisica de Materiales (UCM). P.O. Box 155, Las Rozas, Madrid 28230 (Spain); Micromag S.L., Las Rozas, Madrid 28230 (Spain)

    2010-05-15

    It is shown that copper microwires composite media attenuates microwave reflection of metallic surfaces. We show how the distance to the metallic surface, as well as the length and volume fraction of microwires, determine the frequency of maximum absorption and the return loss level. Furthermore, we were able to fit the experimental results with a theoretical model based on Maxwell-Garnett mixing formula.

  17. GPR measurements of attenuation in concrete

    Energy Technology Data Exchange (ETDEWEB)

    Eisenmann, David, E-mail: djeisen@cnde.iastate.edu; Margetan, Frank J., E-mail: djeisen@cnde.iastate.edu; Pavel, Brittney, E-mail: djeisen@cnde.iastate.edu [Center for Nondestructive Evaluation, Iowa State University, 1915 Scholl Road, Ames, IA 50011-3042 (United States)

    2015-03-31

    Ground-penetrating radar (GPR) signals from concrete structures are affected by several phenomenon, including: (1) transmission and reflection coefficients at interfaces; (2) the radiation patterns of the antenna(s) being used; and (3) the material properties of concrete and any embedded objects. In this paper we investigate different schemes for determining the electromagnetic (EM) attenuation of concrete from measured signals obtained using commercially-available GPR equipment. We adapt procedures commonly used in ultrasonic inspections where one compares the relative strengths of two or more signals having different travel paths through the material of interest. After correcting for beam spread (i.e., diffraction), interface phenomena, and equipment amplification settings, any remaining signal differences are assumed to be due to attenuation thus allowing the attenuation coefficient (say, in dB of loss per inch of travel) to be estimated. We begin with a brief overview of our approach, and then discuss how diffraction corrections were determined for our two 1.6 GHz GPR antennas. We then present results of attenuation measurements for two types of concrete using both pulse/echo and pitch/catch measurement setups.

  18. Evaluation of the Efficacy, Potential for Vector Transmission, and Duration of Immunity of MP-12, an Attenuated Rift Valley Fever Virus Vaccine Candidate, in Sheep

    Science.gov (United States)

    2015-08-01

    and L (24–26), thus significantly reducing the risk of reversion to viru - lence that might otherwise arise from a recombination event with other viruses ...Transmission, and Duration of Immunity of MP-12, an Attenuated Rift Valley Fever Virus Vaccine Candidate, in Sheep 5a. CONTRACT NUMBER 5b. GRANT...Immunol. 2015; 22(8):930-937 14. ABSTRACT Rift Valley fever virus (RVFV) causes serious disease in ruminants and humans in Africa. In North America

  19. Reporter-Expressing, Replicating-Competent Recombinant Arenaviruses

    Directory of Open Access Journals (Sweden)

    Luis Martínez-Sobrido

    2016-07-01

    Full Text Available Several arenaviruses cause hemorrhagic fever (HF disease in humans and pose an important public health problem in their endemic regions. To date, no Food and Drug Administration (FDA-licensed vaccines are available to combat human arenavirus infections, and current anti-arenaviral drug therapy is limited to an off-label use of ribavirin that is only partially effective. The development of arenavirus reverse genetic approaches has provided investigators with a novel and powerful approach for the study of arenavirus biology including virus–host interactions underlying arenavirus induced disease. The use of cell-based minigenome systems has allowed examining the cis- and trans-acting factors involved in arenavirus replication and transcription, as well as particle assembly and budding. Likewise, it is now feasible to rescue infectious arenaviruses containing predetermined mutations in their genomes to investigate virus-host interactions and mechanisms of pathogenesis. The use of reverse genetics approaches has also allowed the generation of recombinant arenaviruses expressing additional genes of interest. These advances in arenavirus molecular genetics have also facilitated the implementation of novel screens to identify anti-arenaviral drugs, and the development of novel strategies for the generation of arenavirus live-attenuated vaccines. In this review, we will summarize the current knowledge on reporter-expressing, replicating-competent arenaviruses harboring reporter genes in different locations of the viral genome and their use for studying and understanding arenavirus biology and the identification of anti-arenaviral drugs to combat these important human pathogens.

  20. Reporter-Expressing, Replicating-Competent Recombinant Arenaviruses.

    Science.gov (United States)

    Martínez-Sobrido, Luis; de la Torre, Juan Carlos

    2016-07-20

    Several arenaviruses cause hemorrhagic fever (HF) disease in humans and pose an important public health problem in their endemic regions. To date, no Food and Drug Administration (FDA)-licensed vaccines are available to combat human arenavirus infections, and current anti-arenaviral drug therapy is limited to an off-label use of ribavirin that is only partially effective. The development of arenavirus reverse genetic approaches has provided investigators with a novel and powerful approach for the study of arenavirus biology including virus-host interactions underlying arenavirus induced disease. The use of cell-based minigenome systems has allowed examining the cis- and trans-acting factors involved in arenavirus replication and transcription, as well as particle assembly and budding. Likewise, it is now feasible to rescue infectious arenaviruses containing predetermined mutations in their genomes to investigate virus-host interactions and mechanisms of pathogenesis. The use of reverse genetics approaches has also allowed the generation of recombinant arenaviruses expressing additional genes of interest. These advances in arenavirus molecular genetics have also facilitated the implementation of novel screens to identify anti-arenaviral drugs, and the development of novel strategies for the generation of arenavirus live-attenuated vaccines. In this review, we will summarize the current knowledge on reporter-expressing, replicating-competent arenaviruses harboring reporter genes in different locations of the viral genome and their use for studying and understanding arenavirus biology and the identification of anti-arenaviral drugs to combat these important human pathogens.

  1. 双特异性抗肿瘤重组腺病毒对前列腺癌细胞的抑制作用%Inhibition effect on prostate cancer cells by an hTERT-promoter-dependent oncolytic adenovirus that expresses apoptin

    Institute of Scientific and Technical Information of China (English)

    王金辉; 张慕淳; 李霄; 齐延新; 刘广臣; 孙丹丹; 金宁一

    2012-01-01

    Objective To investigate the inhibition effects of an hTERT-promoter-dependent oncolytic adenovirus Ad-VT that expresses apoptin on human prostatic carcinoma cell PC-3. Methods MTT assay was used to measure viability of PC-3 cell which was infected by recombinant adenovirus.The viability was measured at time points of 12,24,36,48,60,72,84 and 96 h after infection.AO/EB staining,DAPI staining,Annexin V assay were used to investigate the lethal effect and style of Ad-VT on PC-3 cell in vitro.The Caspases were measured by whole cell extraction of PC-3 cells 48hrs after infection. Results Ad-VT,Ad-VP3 and Ad-GT inhibited the proliferation of PC-3 cell in vitro.Ad-VT and Ad-GT were more effective than Ad-VP3 on cell growth,P < 0.05.At 48,72,96 h time points,the inhibition effect of Ad-VT on PC-3 cell exhibited a dose related manner.When infection at MOI 100,the inhibition effect of Ad-VT on PC-3 cells exhibited time related manner.The AO/EB staining,DAPI staining,Annexin V assay,Annexin V assays and Caspase assays showed that Ad-VT inhibited the proliferation of PC-3 cells by inducing apoptosis of prostate cancer cells,Loss of cytoplasmic membrane integrity. Conclusions The hTERT-promoterdependent oncolytic adenovirus Ad-VT could effectively suppress prostate cancer cells PC-3 growth.%目的 探讨结合肿瘤特异性启动子hTERTp和特异性抑癌基因Apoptin的腺病毒AdhTERTp-E1 a-A poptin (Ad-VT)对前列腺癌PC-3细胞的抑制作用. 方法 于96孔板内制备前列腺癌PC-3单层细胞(5×103个/孔),分别用100个感染复数(multiplicity of infection,M OI)、10 MOI和1 M0I的重组腺病毒Ad-VT、Ad-CMV-Apoptin(Ad-VP3)、Ad-hTERTp-El a-EGFP (Ad-GT)和Ad-CMV-EGFP(Ad-EGFP)进行感染,以未感染孔为对照,每个剂量设3个复孔.采用96 h噻唑盐(MTT)法,检测重组腺病毒对PC-3细胞的抑制作用.于6孔板制备PC-3单层细胞(1 × 106个/孔),分别用100 MOI的Ad-VT、Ad-VP3、Ad-GT和Ad-EGFP感染PC-3细胞,培养48 h后,分别应

  2. Sizes of mantle heteogeneities and seismic attenuation

    Science.gov (United States)

    Ricard, Y. R.; durand, S.; Chambat, F.; Montagner, J.

    2013-12-01

    The small scale heterogeneity of the mantle, being mostly due to the mixing of petrological heterogeneities by a smooth but chaotic convection should consist in a laminated structure (marble cake) with a power spectrum S(k) varying as 1/k, where k is the wavenumber of the anomalies. This distribution of heterogeneities during convective stirring with negligible diffusion, called Batchelor regime is documented by fluid dynamic experiments and corresponds to what can be inferred from geochemistry and seismic tomography. This laminated structure imposes density, seismic velocity and potentially, anisotropic heterogeneities with similar 1/k spectrums. We show that a seismic wave of wavenumber k_0 crossing such medium is partly reflected by the heterogeneities and the scattered energy has an energy found proportional to k_0 S(2k_0). The reduction of energy for the propagating wave appears therefore equivalent to a quality factor 1/Q proportional to k_0 S(2k_0). With the specific 1/k spectrum of the mantle, the resulting apparent attenuation should therefore be frequency independent. We show that the total contribution of 6-9% RMS density, velocity and anisotropy would explain the observed S and P attenuation of the mantle. Although these values are large there are not unreasonable and we discuss how they are likely overestimated. In this case, most of the attenuation of the Earth would be due to small scale scattering by laminations not by intrinsic dissipation. Intrinsic dissipation must certainly exists but might correspond to a larger, yet unobserved Q. This provocative result would explain the observed very weak frequency dependence of the attenuation, and the fact that bulk attenuation seems negligeable, two observations that have been difficult to explain for 50 years.

  3. Recombination analysis based on the complete genome of bocavirus

    Directory of Open Access Journals (Sweden)

    Chen Shengxia

    2011-04-01

    Full Text Available Abstract Bocavirus include bovine parvovirus, minute virus of canine, porcine bocavirus, gorilla bocavirus, and Human bocaviruses 1-4 (HBoVs. Although recent reports showed that recombination happened in bocavirus, no systematical study investigated the recombination of bocavirus. The present study performed the phylogenetic and recombination analysis of bocavirus over the complete genomes available in GenBank. Results confirmed that recombination existed among bocavirus, including the likely inter-genotype recombination between HBoV1 and HBoV4, and intra-genotype recombination among HBoV2 variants. Moreover, it is the first report revealing the recombination that occurred between minute viruses of canine.

  4. Somatic recombination, gene amplification and cancer.

    Science.gov (United States)

    Ramel, C; Cederberg, H; Magnusson, J; Vogel, E; Natarajan, A T; Mullender, L H; Nivard, J M; Parry, J M; Leyson, A; Comendador, M A; Sierra, L M; Ferreiro, J A; Consuegra, S

    1996-06-12

    The principle objective of this research programme, to analyse chemical induction of somatic recombination and related endpoints, i.e., mobilization of transposing elements and gene amplification, has been approached by means of several assay systems. These have included Drosophila, Saccharomyces and mammalian cell cultures. 6.1. Screening assays for mitotic recombination. A large number of chemicals have been investigated in the three Drosophila assay systems employed--the multiple wing hair/flare wing spot system developed by Graf et al., 1984, the white-ivory system developed by Green et al., 1986 and the white/white+ eye spot assay developed by Vogel (Vogel and Nivard, 1993). Particularly the screening of 181 chemicals, covering a wide array of chemical classes, by the last mentioned assay has shown that measurement of somatic recombination in Drosophila constitutes a sensitive and efficient short-term test which shows a remarkably good correlation with the agent score of 83 short-term tests analysed by ICPEMC (Mendelsohn et al., 1992; Table 2) as well as the assay performance in international collaborative programmes measuring carcinogen/non-carcinogens (de Serres and Ashby, 1981; Ashby et al., 1985, 1988). Also the wing spot assay has gained wide international recognition as a similarly sensitive test. These two assay systems in Drosophila measure both intrachromosomal events and interchromosomal recombination. The white-ivory system on the other hand is based on the loss of a tandem duplication in the white locus, the mechanism of which is less known, but probably involves intrachromosomal recombination. The difference in the mechanism between this assay and the former two was indicated by the lack of response to methotrexate in the white-ivory assay, while this compound was strongly recombinogenic in both the wing spot and white/white+ assays. The use of different strains of Drosophila with the white/white+ assay demonstrated the importance of the

  5. Performance testing of passive autocatalytic recombiners (PARs)

    Energy Technology Data Exchange (ETDEWEB)

    Blanchat, T. [Sandia National Laboratories, Albuquerque, NM (United States); Malliakos, A. [U.S. Nuclear Regulatory Commission, Washington, DC (United States)

    1997-03-01

    Passive autocatalytic recombiners (PARs) have been under consideration in the U.S. as a combustible gas control system in advanced light water reactor (ALWR) containments for design basis and severe accidents. PARs do not require a source of power. Instead they use palladium or platinum as a catalyst to recombine hydrogen and oxygen gases into water vapor upon contact with the catalyst. Energy from the recombination of hydrogen with oxygen is released at a relatively slow but continuous rate into the containment which prevents the pressure from becoming too high. The heat produced creates strong buoyancy effects which increases the influx of the surrounding gases to the recombiner. These natural convective flow currents promote mixing of combustible gases in the containment. PARs are self-starting and self-feeding under a very wide range of conditions. The recombination rate of the PAR system needs to be great enough to keep the concentration of hydrogen (or oxygen) below acceptable limits. There are several catalytic recombiner concepts under development worldwide. The USNRC is evaluating a specific design of a PAR which is in an advanced stage of engineering development and has been proposed for ALWR designs. Sandia National laboratories (SNL), under the sponsorship and the direction of the USNRC, is conducting an experimental program to evaluate the performance of PARs. The PAR will be tested at the SURTSEY facility at SNL. The test plan currently includes the following experiments: experiments will be conducted to define the startup characteristics of PARs (i.e., to define what is the lowest hydrogen concentration that the PAR starts recombining the hydrogen with oxygen); experiments will be used to define the hydrogen depletion rate of PARs as a function of hydrogen concentration; and experiments will be used to define the PAR performance in the presence of high concentrations of steam. (author)

  6. Oral Immunization of Mice With Vaccine of Attenuated Salmonella typhimurium Expressing Helicobacter pylori Urease B Subunit

    Institute of Scientific and Technical Information of China (English)

    XING-LONG YANG; WEN-CHAO LIU; WU-WEI YANG; DONG ZHONG; YU-HU LIU; JING-DONG ZHANG; JIAN-HUI JIANG; SHAN-SHAN LI

    2005-01-01

    Objective To prepare the live recombinant vaccine of attenuated Salmonella typhimurium SL3261 expressing Helicobacterpylori (H. pylori) B subunit (UreB) and to determine whether it could be used as an oral vaccine against H. pylori infection. Methods Using genomic DNA of H. pylori Sydney strain (SS1) as template, the H. pylori UreB gene fragment was amplified by PCR and subcloned into the expression vector pTC01. The recombinant plasmid pTC01-UreB was then transferred into LB5000 to obtain modified forms, and further conversed into the attenuated Salmonella typhimurium SL3261 to obtain recombinant SL3261/pCT01-UreB as an oral immunization reagent, which was then used to orally immunize Balb/c mice twice at a three-week interval. Twelve weeks later, anti-UreB IgA antibodies in intestinal fluid and IgG antibodies in sera were determined by ELISA. The relating data in control groups (including body weight, gastric inflammation, etc.) were also collected. Results The sequencing analysis showed that the UreB gene fragment amplified by PCR was consistent with the sequence of the H. pylori UreB gene. The restriction enzyme digestion revealed that the correct pTC01-UreB was obtained.SDS-PAGE and Western blot showed that a 61KD protein was expressed in SL3261/pTC01-UreB, which could be recognized by anti-H. pylori UreB antiserum and was absent in the control containing only Salmonella typhimurium SL3261 strain. The multiple oral immunization with SL3261/pTC01-UreB could significantly induce H. pylori specific mucosal IgA response as well as serum IgG responses. IFN-γ and IL-10 levels were significantly increased in SL3261/pTC01-UreB group, and no obvious side effect and change in gastric inflammation were observed. Conclusion The attenuated vaccine of Salmonella typhimurium expressing H. pylori UreB can be used as an oral vaccine against H. pylori infection.

  7. The ATM signaling cascade promotes recombination-dependent pachytene arrest in mouse spermatocytes.

    Directory of Open Access Journals (Sweden)

    Sarai Pacheco

    2015-03-01

    Full Text Available Most mutations that compromise meiotic recombination or synapsis in mouse spermatocytes result in arrest and apoptosis at the pachytene stage of the first meiotic prophase. Two main mechanisms are thought to trigger arrest: one independent of the double-strand breaks (DSBs that initiate meiotic recombination, and another activated by persistent recombination intermediates. Mechanisms underlying the recombination-dependent arrest response are not well understood, so we sought to identify factors involved by examining mutants deficient for TRIP13, a conserved AAA+ ATPase required for the completion of meiotic DSB repair. We find that spermatocytes with a hypomorphic Trip13 mutation (Trip13mod/mod arrest with features characteristic of early pachynema in wild type, namely, fully synapsed chromosomes without incorporation of the histone variant H1t into chromatin. These cells then undergo apoptosis, possibly in response to the arrest or in response to a defect in sex body formation. However, TRIP13-deficient cells that additionally lack the DSB-responsive kinase ATM progress further, reaching an H1t-positive stage (i.e., similar to mid/late pachynema in wild type despite the presence of unrepaired DSBs. TRIP13-deficient spermatocytes also progress to an H1t-positive stage if ATM activity is attenuated by hypomorphic mutations in Mre11 or Nbs1 or by elimination of the ATM-effector kinase CHK2. These mutant backgrounds nonetheless experience an apoptotic block to further spermatogenic progression, most likely caused by failure to form a sex body. DSB numbers are elevated in Mre11 and Nbs1 hypomorphs but not Chk2 mutants, thus delineating genetic requirements for the ATM-dependent negative feedback loop that regulates DSB numbers. The findings demonstrate for the first time that ATM-dependent signaling enforces the normal pachytene response to persistent recombination intermediates. Our work supports the conclusion that recombination defects trigger

  8. Recombinant canine distemper virus serves as bivalent live vaccine against rabies and canine distemper.

    Science.gov (United States)

    Wang, Xijun; Feng, Na; Ge, Jinying; Shuai, Lei; Peng, Liyan; Gao, Yuwei; Yang, Songtao; Xia, Xianzhu; Bu, Zhigao

    2012-07-20

    Effective, safe, and affordable rabies vaccines are still being sought. Attenuated live vaccine has been widely used to protect carnivores from canine distemper. In this study, we generated a recombinant canine distemper virus (CDV) vaccine strain, rCDV-RVG, expressing the rabies virus glycoprotein (RVG) by using reverse genetics. The recombinant virus rCDV-RVG retained growth properties similar to those of vector CDV in Vero cell culture. Animal studies demonstrated that rCDV-RVG was safe in mice and dogs. Mice inoculated intracerebrally or intramuscularly with rCDV-RVG showed no apparent signs of disease and developed a strong rabies virus (RABV) neutralizing antibody response, which completely protected mice from challenge with a lethal dose of street virus. Canine studies showed that vaccination with rCDV-RVG induced strong and long-lasting virus neutralizing antibody responses to RABV and CDV. This is the first study demonstrating that recombinant CDV has the potential to serve as bivalent live vaccine against rabies and canine distemper in animals.

  9. Attenuation of seismic waves in Central Egypt

    Directory of Open Access Journals (Sweden)

    Mamdouh Abbas Morsy

    2013-06-01

    Full Text Available Attenuation of seismic waves in central Egypt had never been studied before. The results of the research on the seismic attenuation are based upon the information collected by the seismological network from 1998 to 2011. 855 earthquakes were selected from the Egyptian seismological catalog, with their epicenter distances between 15 and 150 km, their magnitudes ranging from 2 and 4.1 and focal depths reaching up to 30 km. The first systematic study of attenuation derived from the P-, S- and coda wave in the frequency range 1–24 Hz is presented. In the interpretation of the results both single and multiple scattering in a half space are considered. The single scattering model proposed by Sato (1977 was used. Two methods, the coda (Qc and the Multiple Lapse Time Window (MLTW method are used. The aim of this study is to validate these interpretations in the region and to try to identify the effects of attenuation due to intrinsic (Qi and scattering attenuation (Qsc. The mean Qc value calculated was Qc = (39 ± 1f1.0±0.009. The average Qc at 1.5 Hz is (53 ± 6 and Qc = (900 ± 195 at 24 Hz with Qo ranging between 23 and 107, where η ranging between 0.9 and 1.3. The quality factor (Q was estimated from spectra of P- and S-waves by applying a spectral ratio technique. The results show variations in Qp and QS as a function of frequency, according to the power law Q = 56η1.1. The seismic albedo is 0.7 at all stations and it mean that the earthquake activity is due to tectonic origin. The attenuation and frequency dependency for different paths and the correlation of the results with the geotectonic of the region are presented. The Qc values were calculated and correlated with the geology and tectonics of the area. The relatively low Qo and the high frequency dependency agree with the values of a region characterized by a low tectonic activity and vise versa.

  10. Autophagy is involved in recombinant Newcastle disease virus (rL-RVG)-induced cell death of stomach adenocarcinoma cells in vitro.

    Science.gov (United States)

    Bu, Xu-Feng; Wang, Mu-Bing; Zhang, Zhi-Jian; Zhao, Ying-Hai; Li, Mi; Yan, Yu-Lan

    2015-08-01

    Oncolytic viruses can kill malignant cells while sparing normal cells. Multiple pathways are involved in this action. The antitumor effects of viral infection on SGC-7901 and AGS cells were investigated. We measured endoplasmic reticulum stress and autophagy caused by the recombinant avirulent Newcastle disease virus (NDV) LaSota strain expressing the rabies virus glycoprotein (rL-RVG) and the NDV wild-type strain. The dose-response curves were analyzed using the MTT assay. The expression of RVG was detected by western blotting, RT-PCR and immunofluorescence analyses. Cell death and autophagy were observed using transmission electron microscopy, TUNEL and western blotting. Endoplasmic reticulum stress and the mitochondrial transmembrane potential were detected by western blotting and immunofluorescence, respectively. Immunofluorescence, western blot and RT-PCR analyses indicated that RVG gene and protein were expressed in SGC-7901 and AGS cells infected by rL-RVG. MTT and TUNEL analyses showed that the growth of SGC-7901 and AGS cells in the rL-RVG-infected group was significantly inhibited compared with the wild-type NDV-infected group (prL-RVG and NDV induced increases in apoptosis, endoplasmic reticulum stress, and autophagy in the SGC-7901 and AGS cells. However, apoptosis and autophagy decreased in these cells after the application of the autophagy pathway inhibitor 3-MA or ATG-5-specific siRNA. Immunofluorescence analysis showed that the mitochondrial membrane potential collapsed. Taken together, these results indicate that the rL-RVG virus group is much more powerful compared with the NDV-infected group (prL-RVG and NDV are potent antitumor agents that induce autophagy.

  11. Molecular hydrogen in the cosmic recombination epoch

    CERN Document Server

    Alizadeh, Esfandiar

    2010-01-01

    The advent of precise measurements of the cosmic microwave background (CMB) anisotropies has motivated correspondingly precise calculations of the cosmic recombination history. Cosmic recombination proceeds far out of equilibrium because of a "bottleneck" at the $n=2$ level of hydrogen: atoms can only reach the ground state via slow processes: two-photon decay or Lyman-$\\alpha$ resonance escape. However, even a small primordial abundance of molecules could have a large effect on the interline opacity in the recombination epoch and lead to an additional route for hydrogen recombination. Therefore, this paper computes the abundance of the H$_2$ molecule during the cosmic recombination epoch. Hydrogen molecules in the ground electronic levels X$^1\\Sigma^+_g$ can either form from the excited H$_2$ electronic levels B$^1\\Sigma^+_u$ and C$^1\\Pi_u$ or through the charged particles H$_2^+$, HeH$^+$ and H$^-$. We follow the transitions among all of these species, resolving the rotational and vibrational sub-levels. Si...

  12. Polyploidization increases meiotic recombination frequency in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Rehmsmeier Marc

    2011-04-01

    Full Text Available Abstract Background Polyploidization is the multiplication of the whole chromosome complement and has occurred frequently in vascular plants. Maintenance of stable polyploid state over generations requires special mechanisms to control pairing and distribution of more than two homologous chromosomes during meiosis. Since a minimal number of crossover events is essential for correct chromosome segregation, we investigated whether polyploidy has an influence on the frequency of meiotic recombination. Results Using two genetically linked transgenes providing seed-specific fluorescence, we compared a high number of progeny from diploid and tetraploid Arabidopsis plants. We show that rates of meiotic recombination in reciprocal crosses of genetically identical diploid and autotetraploid Arabidopsis plants were significantly higher in tetraploids compared to diploids. Although male and female gametogenesis differ substantially in meiotic recombination frequency, both rates were equally increased in tetraploids. To investigate whether multivalent formation in autotetraploids was responsible for the increased recombination rates, we also performed corresponding experiments with allotetraploid plants showing strict bivalent pairing. We found similarly increased rates in auto- and allotetraploids, suggesting that the ploidy effect is independent of chromosome pairing configurations. Conclusions The evolutionary success of polyploid plants in nature and under domestication has been attributed to buffering of mutations and sub- and neo-functionalization of duplicated genes. Should the data described here be representative for polyploid plants, enhanced meiotic recombination, and the resulting rapid creation of genetic diversity, could have also contributed to their prevalence.

  13. Graded Recombination Layers for Multijunction Photovoltaics

    KAUST Repository

    Koleilat, Ghada I.

    2012-06-13

    Multijunction devices consist of a stack of semiconductor junctions having bandgaps tuned across a broad spectrum. In solar cells this concept is used to increase the efficiency of photovoltaic harvesting, while light emitters and detectors use it to achieve multicolor and spectrally tunable behavior. In series-connected current-matched multijunction devices, the recombination layers must allow the hole current from one cell to recombine, with high efficiency and low voltage loss, with the electron current from the next cell. We recently reported a tandem solar cell in which the recombination layer was implemented using a progression of n-type oxides whose doping densities and work functions serve to connect, with negligible resistive loss at solar current densities, the constituent cells. Here we present the generalized conditions for design of efficient graded recombination layer solar devices. We report the number of interlayers and the requirements on work function and doping of each interlayer, to bridge an work function difference as high as 1.6 eV. We also find solutions that minimize the doping required of the interlayers in order to minimize optical absorption due to free carriers in the graded recombination layer (GRL). We demonstrate a family of new GRL designs experimentally and highlight the benefits of the progression of dopings and work functions in the interlayers. © 2012 American Chemical Society.

  14. Recombinant expression systems for allergen vaccines.

    Science.gov (United States)

    Singh, Mohan B; Bhalla, Prem L

    2006-01-01

    Allergen immunotherapy of future is likely to be based on allergy vaccines that contain engineered allergens modified to abolish or substantially reduce their IgE-binding activity in order to remove the risk of unwanted anaphylactic responses. The development of efficient systems for the production of recombinant allergens in sufficient quantities is requirement for establishing use of engineered allergens as components of allergy vaccines. This review outlines relative advantages and disadvantages of various heterologous systems for production of recombinant allergens. Microbial systems are most convenient and cost effective platforms for the production of recombinant allergens. However, lack of post-translational processing implies that some allergens have to be expressed in eukaryotic systems for proper folding and post-translational modifications such as glycosylation. Yeast systems can yield high levels of recombinant allergens but often are associated with hyper- glycosylation problems. Mammalian cell culture systems offer suitable post -translational modifications but are nearly hundred fold more expensive than microbial systems. The use of plants as bio-factories for production of recombinant allergens is emerging as a very attractive option as plants-based production system offer several advantages over other expression systems such as post translational processing of proteins, low production costs, scale up ability and enhanced safety due to absence of animal or human pathogens.

  15. Interleukin-2/Anti-Interleukin-2 Immune Complex Attenuates Cardiac Remodeling after Myocardial Infarction through Expansion of Regulatory T Cells

    Directory of Open Access Journals (Sweden)

    Zhipeng Zeng

    2016-01-01

    Full Text Available CD4+CD25+Foxp3+ regulatory T cells (Treg cells have protective effects in wound healing and adverse ventricular remodeling after myocardial infarction (MI. We hypothesize that the interleukin- (IL- 2 complex comprising the recombinant mouse IL-2/anti-IL-2 mAb (JES6-1 attenuates cardiac remodeling after MI through the expansion of Treg. Mice were subjected to surgical left anterior descending coronary artery ligation and treated with either PBS or IL-2 complex. The IL-2 complex significantly attenuates ventricular remodeling, as demonstrated by reduced infarct size, improved left ventricular (LV function, and attenuated cardiomyocyte apoptosis. The IL-2 complex increased the percentage of CD4+CD25+Foxp3+ Treg cells, which may be recruited to the infarcted heart, and decreased the frequencies of IFN-γ- and IL-17-producing CD4+ T helper (Th cells among the CD4+Foxp3− T cells in the spleen. Furthermore, the IL-2 complex inhibited the gene expression of proinflammatory cytokines as well as macrophage infiltrates in the infarcted myocardium and induced the differentiation of macrophages from M1 to M2 phenotype in border zone of infarcted myocardium. Our studies indicate that the IL-2 complex may serve as a promising therapeutic approach to attenuate adverse remodeling after MI through expanding Treg cells specifically.

  16. Frequency Dependence of Attenuation Constant of Dielectric Materials

    Directory of Open Access Journals (Sweden)

    A. S. Zadgaonkar

    1975-01-01

    Full Text Available Different dielectric materials have been studied for frequency dependence of attenuation constant. The sensitive cathode ray oscillograph method has been used to evaluate to the dielectric constant and loss factor, and from these attenuation constants have been calculated. The temperature remaining constant, a regular increase has been observed in attenuation constant, at higher frequencies of electro-magnetic propagating wave.

  17. On the excess attenuation of sound in the atmosphere

    Science.gov (United States)

    Deloach, R.

    1975-01-01

    The attenuation suffered by an acoustic plane wave propagating from an elevated source to the ground, in excess of absorption losses, was studied. Reported discrepancies between attenuation measurements made in the field and theories which only account for absorption losses are discussed. It was concluded that the scattering of sound by turbulence results in a nonnegligible contribution to the total attenuation.

  18. Attenuation of microwaves by poly-disperse small spheroid particles

    Science.gov (United States)

    Zhang, Peichang; Wang, Zhenhui

    1998-08-01

    Expressions for calculating the attenuation cross sections of poly-disperse, small spheroids, whose rotatory axes are in specific status, have been derived from a universal formula for calculating the attenuation cross section of a particle of arbitrary shape. Attenuation cross sections of liquid, ice, and spongy spheroidal droplets in different size and eccentricity at different wave lengths have been computed and analyzed.

  19. Attenuated partial internal reflection infrared spectroscopy.

    Science.gov (United States)

    Zhang, Zhenfeng; Ewing, George E

    2002-06-01

    A new method for the spectroscopic study of absorbing films is proposed. In contrast to the well-established methods that take advantage of the attenuation of total internal reflection (ATR) to obtain spectra, we intentionally arrange the optics to permit partial internal reflection from the sampling prism face. Attenuated partial internal reflection (APR) spectroscopy is introduced through theoretical calculations and experimental demonstrations. The calculated APR spectra in the infrared region were generated from the Fresnel and Airy equations. Experimentally, APR spectra of water films on a NaCl prism were obtained. APR is more sensitive than ATR, and can easily distinguish water films at the monolayer level (310 pm). The determination of film thickness from interference fringes in APR spectra is also illustrated. It is shown that APR can be used for film thickness measurements that can span 6 orders of magnitude. The limitations of APR are also discussed.

  20. Particle size characterization by ultrasonic attenuation spectra

    Institute of Scientific and Technical Information of China (English)

    Mingxu Su; Minghua Xue; Xiaoshu Cai; Zhitao Shang; Feng Xu

    2008-01-01

    This paper contributes to extracting information from signals of broadband ultrasonic attenuation spectrum for effective utilization in particle size characterization. The single particle scattering model and the coupled-phase model are formulated simultaneously, the relationship between particle size distribution and ultrasonic spectrum is established, and a convergence criterion for calculation is quantified. Demonsa'ation inversion by the optimum regularization factor method is carded out to yield typical numerical results for discussion. With the experimental set-up developed by the Institute of Particle and Two-Phase Flow Measurement (IPTFM) at the University of Shanghai for Science and Technology, sand sediment particle size is measured by attenuation spectrum and analyzed using the above inversion algorithm and theoretical models. To validate the proposed ultrasonic spectrum particle sizing method, results are compared with those obtained by microscopy.

  1. Attenuated psychosis syndrome: benefits of explicit recognition

    Science.gov (United States)

    SCHIFFMAN, Jason; CARPENTER, William T

    2015-01-01

    Summary Given the unique characteristics of people who meet criteria for attenuated psychosis syndrome (APS) and the growing literature on the clinical benefits of providing services to individuals who meet these criteria, the APS diagnosis serves an important, and previously missing, role in psychiatry. The promotion of the APS diagnosis should help reduce the over-diagnosis and over-treatment of individuals with prodromal psychotic conditions and it should also encourage expanded training about attenuated psychosis among clinicians who primarily provide services to youth (a primary group who are diagnosed with APS). Only some of the individuals with APS subsequently develop psychosis, but all have existing clinical needs – regardless of subsequent conversion. The formal recognition of APS in DSM-5 will facilitate the research needed to identify and meet those needs. PMID:25852257

  2. Carcinoma cervix with fat attenuating skull metastases

    Institute of Scientific and Technical Information of China (English)

    Anuradha Kapali; Atmakuri Sateesh Kumar; Mukunda Malathi; S D Shamsundar

    2016-01-01

    Skeletal metastasis in carcinoma cervix occurs in about 0.8-23% of cases. These lesions are usually radiographically lytic. Very few cases of metastases to the skull have been identiifed, about 5 cases to the best of our knowledge. We present a case of adenosquamous cell carcinoma of cervix with fat attenuating skull metastases in a 38-year-old lady that is not reported till date. The lesion was lytic, expansile and with negative attenuation of -15 to -30 Hounsifeld units corresponding to fat.Metastases must be included in the differentials of scalp lesions. A history of recent onset of swelling and associated lytic areas in calvarium on contrast enhanced computed tomography with multiplicity can give a clue to metastatic nature of disease.

  3. LCLS XTOD Attenuator System System Concept Report

    Energy Technology Data Exchange (ETDEWEB)

    Kishiyama, K; Roeben, M; Trent, J; Ryutov, D; Shen, S

    2006-04-12

    The attenuator system for the Linac Coherent Light Source (LCLS) X-ray Transport, Optics and Diagnostics (XTOD) system has been configured and analyzed by the Lawrence Livermore National Laboratory's New Technologies Engineering Division (NTED) as requested by the SLAC/LCLS program. The system layout, performance analyses and selection of the vacuum components are presented in this System Conceptual Review (SCR) report. Also included are the plans for prototype, procurement, mechanical integration, and the cost estimates.

  4. Narrow terahertz attenuation signatures in Bacillus thuringiensis.

    Science.gov (United States)

    Zhang, Weidong; Brown, Elliott R; Viveros, Leamon; Burris, Kellie P; Stewart, C Neal

    2014-10-01

    Terahertz absorption signatures from culture-cultivated Bacillus thuringiensis were measured with a THz photomixing spectrometer operating from 400 to 1200 GHz. We observe two distinct signatures centered at ∼955 and 1015 GHz, and attribute them to the optically coupled particle vibrational resonance (surface phonon-polariton) of Bacillus spores. This demonstrates the potential of the THz attenuation signatures as "fingerprints" for label-free biomolecular detection.

  5. Molecular Characterization of Attenuated Junin Virus Variants.

    Science.gov (United States)

    1992-07-14

    No. DAMD17-89-Z-9024 Area de Quimica Biologica y Biologia Molecular Facultad de Ciencias Exactas Universidad Nacional de La Plata Calles 47 y 115, 1900...MONITORING ORGANIZATION Area de Quimica Biologica (If applicable) y Biologia Molecular I 6c. ADDRESS (City, State, and ZIPCode) 7b. ADDRESS (City, State...AD-A260 128 AD____ MOLECULAR CHARACTERIZATION OF ATTENUATED JUNIN VIRUS VARIANTS FINAL REPORT VICTOR ROMANOWSKI PABLO D. GHIRINGHELLI CESAR G

  6. Recombination Processes and Nonlinear Markov Chains.

    Science.gov (United States)

    Pirogov, Sergey; Rybko, Alexander; Kalinina, Anastasia; Gelfand, Mikhail

    2016-09-01

    Bacteria are known to exchange genetic information by horizontal gene transfer. Since the frequency of homologous recombination depends on the similarity between the recombining segments, several studies examined whether this could lead to the emergence of subspecies. Most of them simulated fixed-size Wright-Fisher populations, in which the genetic drift should be taken into account. Here, we use nonlinear Markov processes to describe a bacterial population evolving under mutation and recombination. We consider a population structure as a probability measure on the space of genomes. This approach implies the infinite population size limit, and thus, the genetic drift is not assumed. We prove that under these conditions, the emergence of subspecies is impossible.

  7. Recombinant human erythropoietin in sports: a review

    Directory of Open Access Journals (Sweden)

    Rafael Maia de Almeida Bento

    2003-06-01

    Full Text Available Erythropoietin is an endogenous hormone of glicoproteic nature secreted by the kidneys and is the main regulator of the erythropoiesis. An alteration in its production generates a disturbance in the plasmatic concentration giving rise to several types of pathologies related to the hematopoietic system. The recombinant forms of erythropoietin have indiscriminately been used by athletes, mainly in endurance sports, by increasing the erythrocytes concentration, generating a better delivery of oxygen to the muscle tissue. The administration of recombinant erythropoietin was prohibited by the International Olympic Committee and its use considered as doping. This review has the intention to describe the physical, biological and pharmacokinetic properties of the endogenous erythropoietin, as well as its recombinant form, describing also its use in sports and the process of searching methodologies for its detection in doping control.

  8. Genetics of meiosis and recombination in mice.

    Science.gov (United States)

    Bolcun-Filas, Ewelina; Schimenti, John C

    2012-01-01

    Meiosis is one of the most critical developmental processes in sexually reproducing organisms. One round of DNA replication followed by two rounds of cell divisions results in generation of haploid gametes (sperm and eggs in mammals). Meiotic failure typically leads to infertility in mammals. In the process of meiotic recombination, maternal and paternal genomes are shuffled, creating new allelic combinations and thus genetic variety. However, in order to achieve this, meiotic cells must self-inflict DNA damage in the form of programmed double-strand breaks (DSBs). Complex processes evolved to ensure proper DSB repair, and to do so in a way that favors interhomolog reciprocal recombination and crossovers. The hallmark of meiosis, a structurally conserved proteinaceous structure called the synaptonemal complex, is found only in meiotic cells. Conversely, meiotic homologous recombination is an adaptation of the mitotic DNA repair process but involving specialized proteins. In this chapter, we summarize current developments in mammalian meiosis enabled by genetically modified mice.

  9. Regulation of Homologous Recombination by SUMOylation

    DEFF Research Database (Denmark)

    Pinela da Silva, Sonia Cristina

    Double-strand breaks (DSBs) are one of the most deleterious types of DNA lesions challenging genome integrity. The DNA damage response (DDR) promotes fast and effective detection and repair of the damaged DNA, leading to cell cycle arrest through checkpoint activation and the recruitment of repair...... factors such as the homologous recombination (HR) machinery. HR constitutes the main DSB repair pathway in Saccharomyces cerevisiae and despite being largely considered an error-free process and essential for genome stability, uncontrolled recombination can lead to loss of heterozygosity, translocations....... In this study I present new insights for the role of SUMOylation in regulating HR by dissecting the role of SUMO in the interaction between the central HR-mediator protein Rad52 and its paralogue Rad59 and the outcome of recombination. This data provides evidence for the importance of SUMO in promoting protein...

  10. Generation of Modified Pestiviruses by Targeted Recombination

    DEFF Research Database (Denmark)

    Rasmussen, Thomas Bruun; Friis, Martin Barfred; Risager, Peter Christian

    involves targeted modification of viral cDNA genomes, cloned within BACs, by Red/ET recombination-mediated mutagenesis in E.coli DH10B cells. Using recombination-mediated mutagenesis for the targeted design, the work can be expedited and focused in principal on any sequence within the viral genome......Infectious cDNA clones are a prerequisite for directed genetic manipulation of pestivirus RNA genomes. We have developed a novel strategy to facilitate manipulation and rescue of modified pestiviruses from infectious cDNA clones based on bacterial artificial chromosomes (BACs). The strategy...... and hence is not limited to the use of internal restriction sites. Rescue of modified pestiviruses can be obtained by electroporation of cell cultures with full-length RNA transcripts in vitro transcribed from the recombined BAC clones. We have used this approach to generate a series of new pestivirus BACs...

  11. Novel Intriguing Strategies Attenuating to Sarcopenia

    Directory of Open Access Journals (Sweden)

    Kunihiro Sakuma

    2012-01-01

    Full Text Available Sarcopenia, the age-related loss of skeletal muscle mass, is characterized by a deterioration of muscle quantity and quality leading to a gradual slowing of movement, a decline in strength and power, increased risk of fall-related injury, and, often, frailty. Since sarcopenia is largely attributed to various molecular mediators affecting fiber size, mitochondrial homeostasis, and apoptosis, the mechanisms responsible for these deleterious changes present numerous therapeutic targets for drug discovery. Resistance training combined with amino acid-containing supplements is often utilized to prevent age-related muscle wasting and weakness. In this review, we summarize more recent therapeutic strategies (myostatin or proteasome inhibition, supplementation with eicosapentaenoic acid (EPA or ursolic acid, etc. for counteracting sarcopenia. Myostatin inhibitor is the most advanced research with a Phase I/II trial in muscular dystrophy but does not try the possibility for attenuating sarcopenia. EPA and ursolic acid seem to be effective as therapeutic agents, because they attenuate the degenerative symptoms of muscular dystrophy and cachexic muscle. The activation of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α in skeletal muscle by exercise and/or unknown supplementation would be an intriguing approach to attenuating sarcopenia. In contrast, muscle loss with age may not be influenced positively by treatment with a proteasome inhibitor or antioxidant.

  12. Natural Biological Attenuation of Benzene in Groundwater

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Benzene has been found in subsurface unsaturated soil and groundwater beneath a petro-chemical plant. Although the groundwater contained several mg/L of benzene in the area immediately beneath the source, benzene was not detected in monitoring wells approximately 800m down stream. All kinds of physical processes such as adsorption and advection/dispersion are considered to account for the observed attenuation. The results indicated that the attenuation was primarily due to natural biological processes occurring within the aquifer. The evidence for the natural bioremediation of benzene from the groundwater included: (1) analysis of groundwater chemistry, (2) laboratory studies demonstrating benzene biodegradation in aquifer samples, and (3) computer simulations examining benzene transport. Laboratory experiments indicated that for conditions similar to those in the plume, the aerobic degradation of benzene by the naturally occurring microorganisms in the polluted groundwater samples was quite rapid with a half-life time of from 5 to 15 days. In situ analyses indicated the level of dissolved oxygen in the groundwater was over 2mg/L. Thus, oxygen should not limit the biodegradation. In fact, the benzene was also shown to degrade under anaerobic conditions. The results from the modeling simulations indicate that biodegradation is the dominant process influencing attenuation of the benzene.

  13. Breaking the sound barrier in recombination fronts

    CERN Document Server

    Williams, R J R

    1995-01-01

    We exploit a generic instability in the integration of steady, sonic near-isothermal flows to find the complete transition diagram for recombination fronts (for a model system of equations). The instability requires the integration of the flow equations for speeds between the isothermal and adiabatic sound speeds to be performed with particular care. As a result of this, the previous work of Newman & Axford on the structure of recombination fronts neglected an important class of solution, that of transonic fronts; our method is readily extensible to a more complete treatment of the ionization structure. Future papers will apply these results in models of the structure of ultracompact HII regions.

  14. Quantum Electrodynamics Theory of Laser Assisted Recombination

    Institute of Scientific and Technical Information of China (English)

    敖淑艳; 程太旺; 李晓峰; 潘守甫; 傅盘铭

    2003-01-01

    Using a formal scattering theoretical approach, we develop a nonperturbative quantum electrodynamics theory to describe laser assisted recombination (LAR), in which an electron initially in the quantized Volkov state recombines with an ion and emits a high-energy photon with frequency defined by energy conservation laws.The transition probability is expressed as an analytic closed form and the spectrum of LAR reflects mainly the properties of general Bessel functions. For the case of a fast electron the LAR spectrum is confined in a well-defined range, while for a slow electron, the LAR spectrum exhibits a double-plateau structure.

  15. Thermal Recombination: Beyond the Valence Quark Approximation

    CERN Document Server

    Müller, B; Bass, S A

    2005-01-01

    Quark counting rules derived from recombination models agree well with data on hadron production at intermediate transverse momenta in relativistic heavy-ion collisions. They convey a simple picture of hadrons consisting only of valence quarks. We discuss the inclusion of higher Fock states that add sea quarks and gluons to the hadron structure. We show that, when recombination occurs from a thermal medium, hadron spectra remain unaffected by the inclusion of higher Fock states. However, the quark number scaling for elliptic flow is somewhat affected. We discuss the implications for our understanding of data from the Relativistic Heavy Ion Collider.

  16. Seismic Attenuation Inversion with t* Using tstarTomog.

    Energy Technology Data Exchange (ETDEWEB)

    Preston, Leiph

    2014-09-01

    Seismic attenuation is defined as the loss of the seismic wave amplitude as the wave propagates excluding losses strictly due to geometric spreading. Information gleaned from seismic waves can be utilized to solve for the attenuation properties of the earth. One method of solving for earth attenuation properties is called t*. This report will start by introducing the basic theory behind t* and delve into inverse theory as it pertains to how the algorithm called tstarTomog inverts for attenuation properties using t* observations. This report also describes how to use the tstarTomog package to go from observed data to a 3-D model of attenuation structure in the earth.

  17. Recombinant microorganisms for increased production of organic acids

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Jian; Kleff, Susanne; Guettler, Michael V

    2013-04-30

    Disclosed are recombinant microorganisms for producing organic acids. The recombinant microorganisms express a polypeptide that has the enzymatic activity of an enzyme that is utilized in the pentose phosphate cycle. The recombinant microorganism may include recombinant Actinobacillus succinogenes that has been transformed to express a Zwischenferment (Zwf) gene. The recombinant microorganisms may be useful in fermentation processes for producing organic acids such as succinic acid and lactic acid. Also disclosed are novel plasmids that are useful for transforming microorganisms to produce recombinant microorganisms that express enzymes such as Zwf.

  18. Rational Design of Human Metapneumovirus Live Attenuated Vaccine Candidates by Inhibiting Viral mRNA Cap Methyltransferase

    Science.gov (United States)

    Zhang, Yu; Wei, Yongwei; Zhang, Xiaodong; Cai, Hui; Niewiesk, Stefan

    2014-01-01

    ABSTRACT The paramyxoviruses human respiratory syncytial virus (hRSV), human metapneumovirus (hMPV), and human parainfluenza virus type 3 (hPIV3) are responsible for the majority of pediatric respiratory diseases and inflict significant economic loss, health care costs, and emotional burdens. Despite major efforts, there are no vaccines available for these viruses. The conserved region VI (CR VI) of the large (L) polymerase proteins of paramyxoviruses catalyzes methyltransferase (MTase) activities that typically methylate viral mRNAs at positions guanine N-7 (G-N-7) and ribose 2′-O. In this study, we generated a panel of recombinant hMPVs carrying mutations in the S-adenosylmethionine (SAM) binding site in CR VI of L protein. These recombinant viruses were specifically defective in ribose 2′-O methylation but not G-N-7 methylation and were genetically stable and highly attenuated in cell culture and viral replication in the upper and lower respiratory tracts of cotton rats. Importantly, vaccination of cotton rats with these recombinant hMPVs (rhMPVs) with defective MTases triggered a high level of neutralizing antibody, and the rats were completely protected from challenge with wild-type rhMPV. Collectively, our results indicate that (i) amino acid residues in the SAM binding site in the hMPV L protein are essential for 2′-O methylation and (ii) inhibition of mRNA cap MTase can serve as a novel target to rationally design live attenuated vaccines for hMPV and perhaps other paramyxoviruses, such as hRSV and hPIV3. IMPORTANCE Human paramyxoviruses, including hRSV, hMPV, and hPIV3, cause the majority of acute upper and lower respiratory tract infections in humans, particularly in infants, children, the elderly, and immunocompromised individuals. Currently, there is no licensed vaccine available. A formalin-inactivated vaccine is not suitable for these viruses because it causes enhanced lung damage upon reinfection with the same virus. A live attenuated vaccine

  19. Acute reactogenicity after intramuscular immunization with recombinant vesicular stomatitis virus is linked to production of IL-1β.

    Directory of Open Access Journals (Sweden)

    Kathleen Athearn

    Full Text Available Vaccines based on live viruses are attractive because they are immunogenic, cost-effective, and can be delivered by multiple routes. However, live virus vaccines also cause reactogenic side effects such as fever, myalgia, and injection site pain that have reduced their acceptance in the clinic. Several recent studies have linked vaccine-induced reactogenic side effects to production of the pro-inflammatory cytokine interleukin-1β (IL-1β in humans. Our objective was therefore to determine whether IL-1β contributed to pathology after immunization with recombinant vesicular stomatitis virus (rVSV vaccine vectors, and if so, to identify strategies by which IL-1β mediated pathology might be reduced without compromising immunogenicity. We found that an rVSV vaccine induced local and systemic production of IL-1β in vivo, and that accumulation of IL-1β correlated with acute pathology after rVSV immunization. rVSV-induced pathology was reduced in mice deficient in the IL-1 receptor Type I, but the IL-1R-/- mice were fully protected from lethal rechallenge with a high dose of VSV. This result demonstrated that IL-1 contributed to reactogenicity of the rVSV, but was dispensable for induction of protective immunity. The amount of IL-1β detected in mice deficient in either caspase-1 or the inflammasome adaptor molecule ASC after rVSV immunization was not significantly different than that produced by wild type animals, and caspase-1-/- and ASC-/- mice were only partially protected from rVSV-induced pathology. Those data support the idea that some of the IL-1β expressed in vivo in response to VSV may be activated by a caspase-1 and ASC-independent mechanism. Together these results suggest that rVSV vectors engineered to suppress the induction of IL-1β, or signaling through the IL-1R would be less reactogenic in vivo, but would retain their immunogenicity and protective capacity. Such rVSV would be highly desirable as either vaccine vectors or

  20. Recombination-mediated genetic engineering of a bacterial artificial chromosome clone of modified vaccinia virus Ankara (MVA)

    DEFF Research Database (Denmark)

    Cottingham, Matthew G; Andersen, Rikke F; Spencer, Alexandra J

    2008-01-01

    The production, manipulation and rescue of a bacterial artificial chromosome clone of Vaccinia virus (VAC-BAC) in order to expedite construction of expression vectors and mutagenesis of the genome has been described (Domi & Moss, 2002, PNAS99 12415-20). The genomic BAC clone was 'rescued' back...... to infectious virus using a Fowlpox virus helper to supply transcriptional machinery. We apply here a similar approach to the attenuated strain Modified Vaccinia virus Ankara (MVA), now widely used as a safe non-replicating recombinant vaccine vector in mammals, including humans. Four apparently full......K counterselection to insert an antigen expression cassette lacking a tandem marker gene into the traditional thymidine kinase locus of MVA-BAC. MVA continues to feature prominently in clinical trials of recombinant vaccines against diseases such as HIV-AIDS, malaria and tuberculosis. Here we demonstrate in proof-of-concept...

  1. The Relationship between Albumin-Binding Capacity of Recombinant Polypeptide and Changes in the Structure of Albumin-Binding Domain.

    Science.gov (United States)

    Bormotova, E A; Gupalova, T V

    2015-07-01

    Many bacteria express surface proteins interacting with human serum albumin (HSA). One of these proteins, PAB from anaerobic bacteria, contains an albumin-binding domain consisting of 45 amino acid residues known as GA domain. GA domains are also found in G proteins isolated from human streptococcal strains (groups C and G) and of albumin-binding protein isolated from group G streptococcal strains of animal origin. The GA domain is a left-handed three-helix bundle structure in which amino acid residues of the second and third helixes are involved in albumin binding. We studied the relationship between HSA-binding activity of the recombinant polypeptide isolated from group G streptococcus of animal origin and structure of the GA domain is studied. Structural changes in GA domain significantly attenuated HAS-binding capacity of the recombinant polypeptide. Hence, affinity HSA-binding polypeptide depends on stability of GA domain structure.

  2. Attenuation of IL-7 receptor signaling is not required for allelic exclusion.

    Science.gov (United States)

    Will, Wynette M; Aaker, Joshua D; Burchill, Matthew A; Harmon, Ian R; O'Neil, Jennifer J; Goetz, Christine A; Hippen, Keli L; Farrar, Michael A

    2006-03-15

    Allelic exclusion prevents pre-B cells from generating more than one functional H chain, thereby ensuring the formation of a unique pre-BCR. The signaling processes underlying allelic exclusion are not clearly understood. IL-7R-dependent signals have been clearly shown to regulate the accessibility of the Ig H chain locus. More recent work has suggested that pre-BCR-dependent attenuation of IL-7R signaling returns the H chain loci to an inaccessible state; this process has been proposed to underlie allelic exclusion. Importantly, this model predicts that preventing pre-BCR-dependent down-regulation of IL-7R signaling should interfere with allelic exclusion. To test this hypothesis, we made use of transgenic mice that express a constitutively active form of STAT5b (STAT5b-CA). STAT5b-CA expression restores V(D)J recombination in IL-7R(-/-) B cells, demonstrating that IL-7 regulates H chain locus accessibility and V(D)J recombination via STAT5 activation. To examine the effects of constitutively active STAT5b on allelic exclusion, we crossed STAT5b-CA mice (which express the IgM(b) allotype) to IgM(a) allotype congenic mice. We found no difference in the percentage of IgM(a)/IgM(b)-coexpressing B cells in STAT5b-CA vs littermate control mice; identical results were observed when crossing STAT5b-CA mice with hen egg lysozyme (HEL) H chain transgenic mice. The HEL transgene enforces allelic exclusion, preventing rearrangement of endogenous H chain genes; importantly, rearrangement of endogenous H chain genes was suppressed to a similar degree in STAT5b-CA vs HEL mice. Thus, attenuation of IL-7R/STAT5 signaling is not required for allelic exclusion.

  3. Evidence for homologous recombination in Chikungunya Virus.

    Science.gov (United States)

    Casal, Pablo E; Chouhy, Diego; Bolatti, Elisa M; Perez, Germán R; Stella, Emma J; Giri, Adriana A

    2015-04-01

    Chikungunya Virus (CHIKV), a mosquito-transmitted alphavirus, causes acute fever and joint pain in humans. Recently, endemic CHIKV infection outbreaks have jeopardized public health in wider geographical regions. Here, we analyze the phylogenetic associations of CHIKV and explore the potential recombination events on 152 genomic isolates deposited in GenBank database. The CHIKV genotypes [West African, Asian, East/Central/South African (ECSA)], and a clear division of ECSA clade into three sub-groups (I-II-III), were defined by Bayesian analysis; similar results were obtained using E1 gene sequences. A nucleotide identity-based approach is provided to facilitate CHIKV classification within ECSA clade. Using seven methods to detect recombination, we found a statistically significant event (p-values range: 1.14×10(-7)-4.45×10(-24)) located within the nsP3 coding region. This finding was further confirmed by phylogenetic networks (PHI Test, p=0.004) and phylogenetic tree incongruence analysis. The recombinant strain, KJ679578/India/2011 (ECSA III), derives from viruses of ECSA III and ECSA I. Our study demonstrates that recombination is an additional mechanism of genetic diversity in CHIKV that might assist in the cross-species transmission process.

  4. Recombinant Bovine Growth Hormone Criticism Grows.

    Science.gov (United States)

    Gaard, Greta

    1995-01-01

    Discusses concerns related to the use of recombinant bovine growth hormone in the United States and other countries. Analyses the issue from the perspectives of animal rights, human health, world hunger, concerns of small and organic farmers, costs to the taxpayer, and environmental questions. A sidebar discusses Canadian review of the hormone.…

  5. Algae-based oral recombinant vaccines.

    Science.gov (United States)

    Specht, Elizabeth A; Mayfield, Stephen P

    2014-01-01

    Recombinant subunit vaccines are some of the safest and most effective vaccines available, but their high cost and the requirement of advanced medical infrastructure for administration make them impractical for many developing world diseases. Plant-based vaccines have shifted that paradigm by paving the way for recombinant vaccine production at agricultural scale using an edible host. However, enthusiasm for "molecular pharming" in food crops has waned in the last decade due to difficulty in developing transgenic crop plants and concerns of contaminating the food supply. Microalgae could be poised to become the next candidate in recombinant subunit vaccine production, as they present several advantages over terrestrial crop plant-based platforms including scalable and contained growth, rapid transformation, easily obtained stable cell lines, and consistent transgene expression levels. Algae have been shown to accumulate and properly fold several vaccine antigens, and efforts are underway to create recombinant algal fusion proteins that can enhance antigenicity for effective orally delivered vaccines. These approaches have the potential to revolutionize the way subunit vaccines are made and delivered - from costly parenteral administration of purified protein, to an inexpensive oral algae tablet with effective mucosal and systemic immune reactivity.

  6. Recombinant Supercharged Polypeptides Restore and Improve Biolubrication

    NARCIS (Netherlands)

    Veeregowda, Deepak H.; Kolbe, Anke; van der Mei, Henny C.; Busscher, Henk J.; Herrmann, Andreas; Sharma, Prashant K.

    2013-01-01

    Recombinant supercharged polypeptides (SUPs) with low cytotoxicity are developed and applied to rejuvenate the lubrication of naturally occurring salivary conditioning films (SCFs). SUPs with 72 positive charges adsorbed and rigidified the SCFs and recruited mucins to form a hydrated layer. These SC

  7. Radiative recombination of excitons in amorphous semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Jai [School of Engineering and Logistics, Faculty Technology, B-41, Charles Darwin University, Darwin, NT 0909 (Australia)]. E-mail: jai.singh@cdu.edu.au

    2005-04-15

    A theory for calculating the radiative lifetime of excitons in amorphous semiconductors is presented. Four possibilities of excitonic radiative recombination are considered and the corresponding rates are derived at thermal equilibrium. The radiative lifetime is calculated from the inverse of the maximum rate for all the four possibilities. Results agree very well with experiments.

  8. Recombinant protein blends: silk beyond natural design.

    Science.gov (United States)

    Dinjaski, Nina; Kaplan, David L

    2016-06-01

    Recombinant DNA technology and new material concepts are shaping future directions in biomaterial science for the design and production of the next-generation biomaterial platforms. Aside from conventionally used synthetic polymers, numerous natural biopolymers (e.g., silk, elastin, collagen, gelatin, alginate, cellulose, keratin, chitin, polyhydroxyalkanoates) have been investigated for properties and manipulation via bioengineering. Genetic engineering provides a path to increase structural and functional complexity of these biopolymers, and thereby expand the catalog of available biomaterials beyond that which exists in nature. In addition, the integration of experimental approaches with computational modeling to analyze sequence-structure-function relationships is starting to have an impact in the field by establishing predictive frameworks for determining material properties. Herein, we review advances in recombinant DNA-mediated protein production and functionalization approaches, with a focus on hybrids or combinations of proteins; recombinant protein blends or 'recombinamers'. We highlight the potential biomedical applications of fibrous protein recombinamers, such as Silk-Elastin Like Polypeptides (SELPs) and Silk-Bacterial Collagens (SBCs). We also discuss the possibility for the rationale design of fibrous proteins to build smart, stimuli-responsive biomaterials for diverse applications. We underline current limitations with production systems for these proteins and discuss the main trends in systems/synthetic biology that may improve recombinant fibrous protein design and production.

  9. Why do bacteria engage in homologous recombination?

    NARCIS (Netherlands)

    Vos, M.

    2009-01-01

    Microbiologists have long recognized that the uptake and incorporation of homologous DNA from outside the cell is a common feature of bacteria, with important implications for their evolution. However, the exact reasons why bacteria engage in homologous recombination remain elusive. This Opinion art

  10. DNA Sequence Alignment during Homologous Recombination.

    Science.gov (United States)

    Greene, Eric C

    2016-05-27

    Homologous recombination allows for the regulated exchange of genetic information between two different DNA molecules of identical or nearly identical sequence composition, and is a major pathway for the repair of double-stranded DNA breaks. A key facet of homologous recombination is the ability of recombination proteins to perfectly align the damaged DNA with homologous sequence located elsewhere in the genome. This reaction is referred to as the homology search and is akin to the target searches conducted by many different DNA-binding proteins. Here I briefly highlight early investigations into the homology search mechanism, and then describe more recent research. Based on these studies, I summarize a model that includes a combination of intersegmental transfer, short-distance one-dimensional sliding, and length-specific microhomology recognition to efficiently align DNA sequences during the homology search. I also suggest some future directions to help further our understanding of the homology search. Where appropriate, I direct the reader to other recent reviews describing various issues related to homologous recombination.

  11. Recombinant CBM-fusion technology - Applications overview.

    Science.gov (United States)

    Oliveira, Carla; Carvalho, Vera; Domingues, Lucília; Gama, Francisco M

    2015-01-01

    Carbohydrate-binding modules (CBMs) are small components of several enzymes, which present an independent fold and function, and specific carbohydrate-binding activity. Their major function is to bind the enzyme to the substrate enhancing its catalytic activity, especially in the case of insoluble substrates. The immense diversity of CBMs, together with their unique properties, has long raised their attention for many biotechnological applications. Recombinant DNA technology has been used for cloning and characterizing new CBMs. In addition, it has been employed to improve the purity and availability of many CBMs, but mainly, to construct bi-functional CBM-fused proteins for specific applications. This review presents a comprehensive summary of the uses of CBMs recombinantly produced from heterologous organisms, or by the original host, along with the latest advances. Emphasis is given particularly to the applications of recombinant CBM-fusions in: (a) modification of fibers, (b) production, purification and immobilization of recombinant proteins, (c) functionalization of biomaterials and (d) development of microarrays and probes.

  12. Quadrivalent Human Papillomavirus recombinant vaccine associated lipoatrophy.

    Science.gov (United States)

    Ojaimi, Samar; Buttery, Jim P; Korman, Tony M

    2009-08-06

    Involutional lipoatrophy, a loss of subcutaneous fat, may be idiopathic, associated with inflammatory skin conditions, or trauma, and has also been reported following injections of medications including insulin, corticosteroids and penicillin. There have also been reports in association with Diptheria Pertussis Tetanus (DPT) vaccine. We report on two cases of lipoatrophy associated with the new Quadrivalent Human Papillomavirus (HPV) recombinant vaccine (Gardasil).

  13. Algae-based oral recombinant vaccines

    Directory of Open Access Journals (Sweden)

    Elizabeth A Specht

    2014-02-01

    Full Text Available Recombinant subunit vaccines are some of the safest and most effective vaccines available, but their high cost and the requirement of advanced medical infrastructure for administration make them impractical for many developing world diseases. Plant-based vaccines have shifted that paradigm by paving the way for recombinant vaccine production at agricultural scale using an edible host. However, enthusiasm for molecular pharming in food crops has waned in the last decade due to difficulty in developing transgenic crop plants and concerns of contaminating the food supply. Microalgae are poised to become the next candidate in recombinant subunit vaccine production, and they present several advantages over terrestrial crop plant-based platforms including scalable and contained growth, rapid transformation, easily obtained stable cell lines, and consistent transgene expression levels. Algae have been shown to accumulate and properly fold several vaccine antigens, and efforts are underway to create recombinant algal fusion proteins that can enhance antigenicity for effective orally-delivered vaccines. These approaches have the potential to revolutionize the way subunit vaccines are made and delivered – from costly parenteral administration of purified protein, to an inexpensive oral algae tablet with effective mucosal and system immune reactivity.

  14. Expression and characterization of recombinant ecarin.

    NARCIS (Netherlands)

    Jonebring, A.; Lange, U.; Bucha, E.; Deinum, J.; Elg, M.; Lovgren, A.

    2012-01-01

    The snake venom protease ecarin from Echis carinatus was expressed in stable transfected CHO-S cells grown in animal component free cell culture medium. Recombinant ecarin (r-ecarin) was secreted from the suspension adapted Chinese Hamster Ovary (CHO-S) host cells as a pro-protein and activation to

  15. Science: The Recombinant DNA Advisory Committee.

    Science.gov (United States)

    Wright, Susan

    1979-01-01

    Reports on the status of the Recombinant DNA Advisory Committee (RAC) and attempts to rationalize Suburban Highway Policy. Effective communication among members of the RAC is a current problem facing the committee. A federal transportation priority spending policy is suggested during these times of money and fuel shortages. (MA)

  16. Recombinant DNA: Scientific and Social Perspectives.

    Science.gov (United States)

    Vandegrift, Vaughn

    1979-01-01

    This article is designed to inform chemical educators not engaged in this technology as to the nature and methods used in the technology, the reasons for scientific and social concern, and the attempts made to assuage concerns involving recombinant DNA research. (author/BB)

  17. Combined immunity of DNA vector and recombinant vaccinia virus expressing Gag proteins of equine infectious anemia virus

    Institute of Scientific and Technical Information of China (English)

    DAI Chunming; ZHANG Xiaoyan; WANG Shuhui; LIU Ying; DUAN Danli; SHEN Rongxian; SHAO Yiming

    2004-01-01

    In order to develop a new vaccine candidate for equine infectious anemia virus (EIAV), gag gene of Chinese donkey leukocyte attenuated strain (EIAV DLV) and its parental virulent strain (EIAV LN) were inserted respectively into the TK region of the Tiantan strain (VV) of vaccinia virus by homologous recombination and the positive clone was confirmed by blue plaque assay. Protein expression was examined by Western blot. Prime and prime-boost procedures were used to immunize mice with two DNA vectors and two recombinant vaccinia viruses expressing EIAV Gag proteins. The results showed that the specific lysis of CTL responses in the DNA+rVV groups was stronger than those in the DNA groups, amounting to 31%. Although the levels of specific antibodies were not significantly different, we could conclude that the recombinant vaccinia virus could boost the cellular responses following DNA vector priming. There was no detectable difference between the immune responses induced by DLV and LN Gag proteins. This data demonstrates that the combined immunity of DNA vector and recombinant vaccinia virus expressing EIAV gag proteins, utilizing the prime-boost procedure, can drive immunized mice to produce powerful cellular responses. These results lay an important foundation for the development of a new EIAV genetic engineering vaccine.

  18. A molecular recombination map of Antirrhinum majus

    Directory of Open Access Journals (Sweden)

    Hudson Andrew

    2010-12-01

    Full Text Available Abstract Background Genetic recombination maps provide important frameworks for comparative genomics, identifying gene functions, assembling genome sequences and for breeding. The molecular recombination map currently available for the model eudicot Antirrhinum majus is the result of a cross with Antirrhinum molle, limiting its usefulness within A. majus. Results We created a molecular linkage map of A. majus based on segregation of markers in the F2 population of two inbred lab strains of A. majus. The resulting map consisted of over 300 markers in eight linkage groups, which could be aligned with a classical recombination map and the A. majus karyotype. The distribution of recombination frequencies and distorted transmission of parental alleles differed from those of a previous inter-species hybrid. The differences varied in magnitude and direction between chromosomes, suggesting that they had multiple causes. The map, which covered an estimated of 95% of the genome with an average interval of 2 cM, was used to analyze the distribution of a newly discovered family of MITE transposons and tested for its utility in positioning seven mutations that affect aspects of plant size. Conclusions The current map has an estimated interval of 1.28 Mb between markers. It shows a lower level of transmission ratio distortion and a longer length than the previous inter-species map, making it potentially more useful. The molecular recombination map further indicates that the IDLE MITE transposons are distributed throughout the genome and are relatively stable. The map proved effective in mapping classical morphological mutations of A. majus.

  19. Oxygen Atom Recombination in Carbon Dioxide Atmospheres

    Science.gov (United States)

    Jamieson, Corey; Garcia, R. M.; Pejakovic, D. A.; Kalogerakis, K. S.

    2009-09-01

    Understanding processes involving atomic oxygen is crucial for the study and modeling of composition, energy transfer, airglow, and transport dynamics in planetary atmospheres. Significant gaps and uncertainties exist in our understanding of the above processes, and often the relevant input from laboratory measurements is missing or outdated. We are conducting experiments to measure the rate coefficients for O + O + CO2 and O + O2 + CO2 recombination and investigate the O2 excited states produced following O-atom recombination. These laboratory measurements are key input for a quantitative understanding and reliable modeling of the atmospheres of the CO2 planets and their airglow. An ArF excimer laser with 193-nm pulsed output radiation is employed to partially photodissociate carbon dioxide. In an ambient-pressure (760 Torr) background of CO2, the O atoms produced recombine in a time scale of a few milliseconds. Detection of laser-induced fluorescence at 845 nm following two-photon excitation near 226 nm monitors the decay of the oxygen atom population. From the temporal evolution of the signal we can extract the rate coefficients for recombination of O + O and O + O2 in the presence of CO2. We also use fluorescence and resonance-enhanced multi-photon ionization techniques to detect the products of the O-atom recombination and subsequent relaxation in CO2. This work is supported by the US National Science Foundation's (NSF) Planetary Astronomy Program. Rosanne Garcia's participation was funded by the NSF Research Experiences for Undergraduates (REU) Program.

  20. Detecting and Analyzing Genetic Recombination Using RDP4.

    Science.gov (United States)

    Martin, Darren P; Murrell, Ben; Khoosal, Arjun; Muhire, Brejnev

    2017-01-01

    Recombination between nucleotide sequences is a major process influencing the evolution of most species on Earth. The evolutionary value of recombination has been widely debated and so too has its influence on evolutionary analysis methods that assume nucleotide sequences replicate without recombining. When nucleic acids recombine, the evolution of the daughter or recombinant molecule cannot be accurately describ