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Sample records for attenuated oncolytic recombinant

  1. Cytotoxic and immunogenic mechanisms of recombinant oncolytic poliovirus.

    Science.gov (United States)

    Brown, Michael C; Gromeier, Matthias

    2015-08-01

    An oncolytic virus (OV) based on poliovirus (PV), the highly attenuated polio/rhinovirus recombinant PVSRIPO, may deliver targeted inflammatory cancer cell killing; a principle that is showing promise in clinical trials for recurrent glioblastoma (GBM). The two decisive factors in PVSRIPO anti-tumor efficacy are selective cytotoxicity and its in situ immunogenic imprint. While our work is focused on what constitutes PVSRIPO cancer cytotoxicity, we are also studying how this engenders host immune responses that are vital to tumor regression. We hypothesize that PVSRIPO cytotoxicity and immunogenicity are inextricably linked in essential, complimentary roles that define the anti-neoplastic response. Herein we delineate mechanisms we unraveled to decipher the basis for PVSRIPO cytotoxicity and its immunotherapeutic potential. PMID:26083317

  2. Current Good Manufacturing Practice Production of an Oncolytic Recombinant Vesicular Stomatitis Viral Vector for Cancer Treatment

    Science.gov (United States)

    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.

    2011-01-01

    Abstract 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 109 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 × 1010 PFU/ml (total yield, 1 × 1013 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. PMID:21083425

  3. Efficient generation of double heterologous promoter controlled oncolytic adenovirus vectors by a single homologous recombination step in Escherichia coli

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    Wildner Oliver

    2006-08-01

    Full Text Available Abstract Background Oncolytic adenoviruses are promising agents for the multimodal treatment of cancer. However, tumor-selectivity is crucial for their applicability in patients. Recent studies by several groups demonstrated that oncolytic adenoviruses with tumor-/tissue-specific expression of the E1 and E4 genes, which are pivotal for adenoviral replication, have a specificity profile that is superior to viruses that solely target the expression of E1 or E4 genes. Presently the E1 and E4 regions are modified in a time consuming sequential fashion. Results Based on the widely used adenoviral cloning system AdEasy we generated a novel transfer vector that allows efficient and rapid generation of conditionally replication-competent adenovirus type 5 based vectors with the viral E1 and E4 genes under the transcriptional control of heterologous promoters. For insertion of the promoters of interest our transfer vector has two unique multiple cloning sites. Additionally, our shuttle plasmid allows encoding of a transgene within the E1A transcription unit. The modifications, including E1 mutations, are introduced into the adenoviral genome by a single homologous recombination step in Escherichia coli. Subsequently infectious viruses are rescued from plasmids. As a proof-of-concept we generated two conditionally replication-competent adenoviruses Ad.Ki•COX and Ad.COX•Ki with the promoters of the Ki-67 protein and the cyclooxygenase-2 (COX-2 driving E1 and E4 and vice versa. Conclusion We demonstrated with our cloning system efficient generation of double heterologous promoter controlled oncolytic adenoviral vectors by a single homologous recombination step in bacteria. The generated viruses showed preferential replication in tumor cells and in a subcutaneous HT-29 colon cancer xenograft model the viruses demonstrated significant oncolytic activity comparable with dl327.

  4. Recombinant vaccinia virus GLV-1h68 is a promising oncolytic vector in the treatment of cholangiocarcinoma.

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    Pugalenthi, Amudhan; Mojica, Kelly; Ady, Justin W; Johnsen, Clark; Love, Damon; Chen, Nanhai G; Aguilar, Richard J; Szalay, Aladar A; Fong, Yuman

    2015-12-01

    Although early stage cholangiocarcinoma (CC) can be cured by surgical extirpation, the options for treatment of advanced stage CC are very few and suboptimal. Oncolytic virotherapy using replication-competent vaccinia virus (VACV) is a promising new strategy to treat human cancers. The ability of oncolytic VACV GLV-1h68 to infect, replicate in, and lyse three human CC cell lines was assayed in vitro and in subcutaneous flank xenografts in athymic nude mice. In this study, we have demonstrated that GLV-1h68 effectively infects and lyses three CC cell lines (KMC-1, KMBC, and KMCH-1) in vitro. Expression of the viral marker gene ruc-gfp facilitated real-time monitoring of infection and replication. Furthermore in athymic nude mice, a single dose of GLV-1h68 significantly suppressed tumor growth. The treatment was well tolerated in all animals. Recombinant VACV GLV-1h68 has significant oncolytic ability against CC both in vitro and in vivo. GLV-1h68 has the potential to be used clinically as a therapeutic agent against CC. PMID:26584530

  5. Efficient generation of double heterologous promoter controlled oncolytic adenovirus vectors by a single homologous recombination step in Escherichia coli

    OpenAIRE

    Wildner Oliver; Hoffmann Dennis

    2006-01-01

    Abstract Background Oncolytic adenoviruses are promising agents for the multimodal treatment of cancer. However, tumor-selectivity is crucial for their applicability in patients. Recent studies by several groups demonstrated that oncolytic adenoviruses with tumor-/tissue-specific expression of the E1 and E4 genes, which are pivotal for adenoviral replication, have a specificity profile that is superior to viruses that solely target the expression of E1 or E4 genes. Presently the E1 and E4 reg...

  6. Attenuated vaccines can recombine to form virulent field viruses.

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    Lee, Sang-Won; Markham, Philip F; Coppo, Mauricio J C; Legione, Alistair R; Markham, John F; Noormohammadi, Amir H; Browning, Glenn F; Ficorilli, Nino; Hartley, Carol A; Devlin, Joanne M

    2012-07-13

    Recombination between herpesviruses has been seen in vitro and in vivo under experimental conditions. This has raised safety concerns about using attenuated herpesvirus vaccines in human and veterinary medicine and adds to other known concerns associated with their use, including reversion to virulence and disease arising from recurrent reactivation of lifelong chronic infection. We used high-throughput sequencing to investigate relationships between emergent field strains and vaccine strains of infectious laryngotracheitis virus (ILTV, gallid herpesvirus 1). We show that independent recombination events between distinct attenuated vaccine strains resulted in virulent recombinant viruses that became the dominant strains responsible for widespread disease in Australian commercial poultry flocks. These findings highlight the risks of using multiple different attenuated herpesvirus vaccines, or vectors, in the same populations. PMID:22798607

  7. Oncolytic Adenoviruses in Cancer Treatment

    Directory of Open Access Journals (Sweden)

    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.

  8. Genetic Manipulation of Homologous Recombination In Vivo Attenuates Intestinal Tumorigenesis.

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    McIlhatton, Michael A; Murnan, Kevin; Carson, Daniel; Boivin, Gregory P; Croce, Carlo M; Groden, Joanna

    2015-07-01

    Although disruption of DNA repair capacity is unquestionably associated with cancer susceptibility in humans and model organisms, it remains unclear if the inherent tumor phenotypes of DNA repair deficiency syndromes can be regulated by manipulating DNA repair pathways. Loss-of-function mutations in BLM, a member of the RecQ helicase family, cause Bloom's syndrome (BS), a rare, recessive genetic disorder that predisposes to many types of cancer. BLM functions in many aspects of DNA homeostasis, including the suppression of homologous recombination (HR) in somatic cells. We investigated whether BLM overexpression, in contrast with loss-of-function mutations, attenuated the intestinal tumor phenotypes of Apc(Min/+) and Apc(Min/+);Msh2(-/-) mice, animal models of familial adenomatous polyposis coli (FAP). We constructed a transgenic mouse line expressing human BLM (BLM-Tg) and crossed it onto both backgrounds. BLM-Tg decreased adenoma incidence in a dose-dependent manner in our Apc(Min/) (+) model of FAP, although levels of GIN were unaffected and concomitantly increased animal survival over 50%. It did not reduce intestinal tumorigenesis in Apc(Min/) (+);Msh2(-/-) mice. We used the pink-eyed unstable (p(un)) mouse model to demonstrate that increasing BLM dosage in vivo lowered endogenous levels of HR by 2-fold. Our data suggest that attenuation of the Min phenotype is achieved through a direct effect of BLM-Tg on the HR repair pathway. These findings demonstrate that HR can be manipulated in vivo to modulate tumor formation at the organismal level. Our data suggest that lowering HR frequencies may have positive therapeutic outcomes in the context of specific hereditary cancer predisposition syndromes, exemplified by FAP. PMID:25908507

  9. ReVOLT: radiation-enhanced viral oncolytic therapy

    International Nuclear Information System (INIS)

    Viral oncolytic therapy has been pursued with renewed interest as the molecular basis of carcinogenesis and viral replication has been elucidated. Genetically engineered, attenuated viruses have been rationally constructed to achieve a therapeutic index in tumor cells compared with surrounding normal tissue. Many of these attenuated mutant viruses have entered clinical trials. Here we review the preclinical literature demonstrating the interaction of oncolytic viruses with ionizing radiation and provides a basis for future clinical trials

  10. Imaging of Viral Thymidine Kinase Gene Expression by Replicating Oncolytic Adenovirus and Prediction of Therapeutic Efficacy

    OpenAIRE

    Kim, Eun-Jung; Yoo, Ji Young; Choi, Young-Hwan; Ahn, Keun-Jae; Lee, Jong-Doo; Yun, Chae-Ok; Yun, Mijin

    2008-01-01

    Purpose We have used a genetically attenuated adenoviral vector which expresses HSVtk to assess the possible additive role of suicidal gene therapy for enhanced oncolytic effect of the virus. Expression of TK was measured using a radiotracer-based molecular counting and imaging system. Materials and Methods Replication-competent recombinant adenoviral vector (Ad-ΔE1B19/55) was used in this study, whereas replication-incompetent adenovirus (Ad-ΔE1A) was generated as a control. Both Ad-ΔE1B19/5...

  11. 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.

  12. Vaccination of cats with an attenuated recombinant myxoma virus expressing feline calicivirus capsid protein.

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    McCabe, Victoria J; Tarpey, Ian; Spibey, Norman

    2002-06-01

    Myxoma virus, a member of the Poxviridae family (genus Leporipoxvirus) is the agent responsible for myxomatosis in the European rabbit. Recombinant myxoma viruses expressing the capsid gene of an F9 strain of feline calicivirus (FCV) were constructed from an apathogenic, laboratory attenuated, isolate of myxoma virus. The FCV capsid genes were recombined into the myxoma growth factor (MGF) locus of the myxoma genome and expressed from synthetic poxvirus promoters. Myxoma virus is unable to replicate productively in feline cells in vitro, however, cells infected with recombinant viruses do express the heterologous antigens from both late and early/late synthetic promoters. Cats immunised with myxoma-FCV recombinant virus generated high levels of serum neutralising antibody and were protected from disease on subsequent challenge with virulent FCV. Furthermore, there was no evidence of transmission of myxoma-FCV recombinant virus from vaccinated to non-vaccinated cats. These results demonstrate the potential of myxoma virus as a safe vaccine vector for use in non-lepori species and in particular the cat. PMID:12057600

  13. Amalgamating oncolytic viruses to enhance their safety, consolidate their killing mechanisms, and accelerate their spread.

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    Ayala-Breton, Camilo; Suksanpaisan, Lukkana; Mader, Emily K; Russell, Stephen J; Peng, Kah-Whye

    2013-10-01

    Oncolytic viruses are structurally and biologically diverse, spreading through tumors and killing them by various mechanisms and with different kinetics. Here, we created a hybrid vesicular stomatitis/measles virus (VSV/MV) that harnesses the safety of oncolytic MV, the speed of VSV, and the tumor killing mechanisms of both viruses. Oncolytic MV targets CD46 and kills by forcing infected cells to fuse with uninfected neighbors, but propagates slowly. VSV spreads rapidly, directly lysing tumor cells, but is neurotoxic and loses oncolytic potency when neuroattenuated by conventional approaches. The hybrid VSV/MV lacks neurotoxicity, replicates rapidly with VSV kinetics, and selectively targets CD46 on tumor cells. Its in vivo performance in a myeloma xenograft model was substantially superior to either MV or widely used recombinant oncolytic VSV-M51. PMID:23842448

  14. Epithelial Junction Opener Improves Oncolytic Adenovirus Therapy in Mouse Tumor Models.

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    Yumul, Roma; Richter, Maximilian; Lu, Zhuo-Zhuang; Saydaminova, Kamola; Wang, Hongjie; Wang, Chung-Huei Katherine; Carter, Darrick; Lieber, André

    2016-04-01

    A central resistance mechanism in solid tumors is the maintenance of epithelial junctions between malignant cells that prevent drug penetration into the tumor. Human adenoviruses (Ads) have evolved mechanisms to breach epithelial barriers. For example, during Ad serotype 3 (Ad3) infection of epithelial tumor cells, massive amounts of subviral penton-dodecahedral particles (PtDd) are produced and released from infected cells to trigger the transient opening of epithelial junctions, thus facilitating lateral virus spread. We show here that an Ad3 mutant that is disabled for PtDd production is significantly less effective in killing of epithelial human xenograft tumors than the wild-type Ad3 virus. Intratumoral spread and therapeutic effect of the Ad3 mutant was enhanced by co-administration of a small recombinant protein (JO; produced in Escherichia coli) that incorporated the minimal junction opening domains of PtDd. We then demonstrated that co-administration of JO with replication-competent Ads that do not produce PtDd (Ad5, Ad35) resulted in greater attenuation of tumor growth than virus injection alone. Furthermore, we genetically modified a conditionally replicating Ad5-based oncolytic Ad (Ad5Δ24) to express a secreted form of JO upon replication in tumor cells. The JO-expressing virus had a significantly greater antitumor effect than the unmodified AdΔ24 version. Our findings indicate that epithelial junctions limit the efficacy of oncolytic Ads and that this problem can be address by co-injection or expression of JO. JO has also the potential for improving cancer therapy with other types of oncolytic viruses. PMID:26993072

  15. 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

    2016-03-01

    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. PMID:26959050

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

    Science.gov (United States)

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

    2016-01-01

    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. PMID:26959050

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

    Directory of Open Access Journals (Sweden)

    Ming Yuan

    2016-03-01

    Full Text Available 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.

  18. 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.

  19. Oncolytic virus therapies.

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    Buonaguro, Franco Maria; Tornesello, Maria Lina; Izzo, Francesco; Buonaguro, Luigi

    2012-11-01

    Oncolytic virus (OV) therapy currently represents one of the most promising approaches to cancer treatment for their dual anticancer mechanisms: direct lysis of cancer cells (oncolytic feature) and activation of the immunosystem (cancer vaccine aspect). The latter demonstrates the advantage of a multi-target approach against multiple tumor-associated antigens. Since the 2005 SFDA (the Chinese FDA) approval for the clinical use of Oncorine™, the first human OV-based cancer treatment, more than 200 patents have been filed worldwide and several Phase I/II studies have been conducted. This patent review analyzes patents and clinical studies of the most promising OV products to highlight the pros and cons of this innovative anticancer approach, which is currently being tested in several cancers (i.e., hepatocellular carcinoma, melanoma and glioblastoma) by systemic as well as intratumoral injection. Clinical results, although effective only for a limited period of time, are encouraging. Combined treatments with radio or chemotherapeutic protocols are also in progress. PMID:24236929

  20. Rational development of an attenuated recombinant cyprinid herpesvirus 3 vaccine using prokaryotic mutagenesis and in vivo bioluminescent imaging.

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    Boutier, Maxime; Ronsmans, Maygane; Ouyang, Ping; Fournier, Guillaume; Reschner, Anca; Rakus, Krzysztof; Wilkie, Gavin S; Farnir, Frédéric; Bayrou, Calixte; Lieffrig, François; Li, Hong; Desmecht, Daniel; Davison, Andrew J; Vanderplasschen, Alain

    2015-02-01

    Cyprinid herpesvirus 3 (CyHV 3) is causing severe economic losses worldwide in common and koi carp industries, and a safe and efficacious attenuated vaccine compatible with mass vaccination is needed. We produced single deleted recombinants using prokaryotic mutagenesis. When producing a recombinant lacking open reading frame 134 (ORF134), we unexpectedly obtained a clone with additional deletion of ORF56 and ORF57. This triple deleted recombinant replicated efficiently in vitro and expressed an in vivo safety/efficacy profile compatible with use as an attenuated vaccine. To determine the role of the double ORF56-57 deletion in the phenotype and to improve further the quality of the vaccine candidate, a series of deleted recombinants was produced and tested in vivo. These experiments led to the selection of a double deleted recombinant lacking ORF56 and ORF57 as a vaccine candidate. The safety and efficacy of this strain were studied using an in vivo bioluminescent imaging system (IVIS), qPCR, and histopathological examination, which demonstrated that it enters fish via skin infection similar to the wild type strain. However, compared to the parental wild type strain, the vaccine candidate replicated at lower levels and spread less efficiently to secondary sites of infection. Transmission experiments allowing water contamination with or without additional physical contact between fish demonstrated that the vaccine candidate has a reduced ability to spread from vaccinated fish to naïve sentinel cohabitants. Finally, IVIS analyses demonstrated that the vaccine candidate induces a protective mucosal immune response at the portal of entry. Thus, the present study is the first to report the rational development of a recombinant attenuated vaccine against CyHV 3 for mass vaccination of carp. We also demonstrated the relevance of the CyHV 3 carp model for studying alloherpesvirus transmission and mucosal immunity in teleost skin. PMID:25700279

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

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    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

  2. Tumor Restrictions to Oncolytic Virus

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    Markus Vähä-Koskela

    2014-04-01

    Full Text Available Oncolytic virotherapy has advanced since the days of its conception but therapeutic efficacy in the clinics does not seem to reach the same level as in animal models. One reason is premature oncolytic virus clearance in humans, which is a reasonable assumption considering the immune-stimulating nature of the oncolytic agents. However, several studies are beginning to reveal layers of restriction to oncolytic virotherapy that are present before an adaptive neutralizing immune response. Some of these barriers are present constitutively halting infection before it even begins, whereas others are raised by minute cues triggered by virus infection. Indeed, we and others have noticed that delivering viruses to tumors may not be the biggest obstacle to successful therapy, but instead the physical make-up of the tumor and its capacity to mount antiviral defenses seem to be the most important efficacy determinants. In this review, we summarize the constitutive and innate barriers to oncolytic virotherapy and discuss strategies to overcome them.

  3. 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.

  4. 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.

  5. 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

  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 activated protein C attenuates coagulopathy and inflammation when administered early in murine pneumococcal pneumonia

    NARCIS (Netherlands)

    M. Schouten; C. van 't Veer; J.J.T.H. Roelofs; B. Gerlitz; B.W. Grinnell; M. Levi; T. van der Poll

    2011-01-01

    Recombinant human activated protein C (APC), which has both anticoagulant and anti-inflammatory properties, improves survival of patients with severe sepsis. This beneficial effect is especially apparent in patients with pneumococcal pneumonia. Earlier treatment with APC in sepsis has been associate

  8. Oncolytic viruses in radiation oncology

    International Nuclear Information System (INIS)

    Oncolytic viruses are investigational cancer treatments. They are currently being assessed as single agents or in combination with standard therapies such as external beam radiotherapy - a DNA damaging agent that is a standard of care for many tumour types. Preclinical data indicate that combinations of oncolytic viruses and radiation therapy are promising, showing additional or synergistic antitumour effects in in vitro and in vivo studies. This interaction has the potential to be multifaceted: viruses may act as radiosensitizing agents, but radiation may also enhance viral oncolysis by increasing viral uptake, replication, gene expression and cell death (apoptosis, autophagy or necrosis) in irradiated cells. Phase I and II clinical trials investigating combinations of viruses and radiation therapy have been completed, paving the way for ongoing phase III studies. The aim of this review is to focus on the therapeutic potential of these combinations and to highlight their mechanistic bases, with particular emphasis on the role of the DNA damage response.

  9. Effective preexposure and postexposure prophylaxis of rabies with a highly attenuated recombinant rabies virus

    OpenAIRE

    Faber, Milosz; Li, Jianwei; Kean, Rhonda B; Hooper, D. Craig; Alugupalli, Kishore R.; Dietzschold, Bernhard

    2009-01-01

    Rabies remains an important public health problem with more than 95% of all human rabies cases caused by exposure to rabid dogs in areas where effective, inexpensive vaccines are unavailable. Because of their ability to induce strong innate and adaptive immune responses capable of clearing the infection from the CNS after a single immunization, live-attenuated rabies virus (RV) vaccines could be particularly useful not only for the global eradication of canine rabies but also for late-stage r...

  10. Multiple antigens of Yersinia pestis delivered by live recombinant attenuated Salmonella vaccine strains elicit protective immunity against plague.

    Science.gov (United States)

    Sanapala, Shilpa; Rahav, Hannah; Patel, Hetal; Sun, Wei; Curtiss, Roy

    2016-05-01

    Based on our improved novel Salmonella vaccine delivery platform, we optimized the recombinant attenuated Salmonella typhimurium vaccine (RASV) χ12094 to deliver multiple Yersinia pestis antigens. These included LcrV196 (amino acids, 131-326), Psn encoded on pYA5383 and F1 encoded in the chromosome, their synthesis did not cause adverse effects on bacterial growth. Oral immunization with χ12094(pYA5383) simultaneously stimulated high antibody titers to LcrV, Psn and F1 in mice and presented complete protection against both subcutaneous (s.c.) and intranasal (i.n.) challenges with high lethal doses of Y. pestis CO92. Moreover, no deaths or other disease symptoms were observed in SCID mice orally immunized with χ12094(pYA5383) over a 60-day period. Therefore, the trivalent S. typhimurium-based live vaccine shows promise for a next-generation plague vaccine. PMID:27060051

  11. Clinical development of oncolytic viruses in China.

    Science.gov (United States)

    Liang, Min

    2012-07-01

    The oncolytic virus, being a promising new therapeutic strategy for cancer, has inspired a wave of recent clinical research and development in China. The first commercialized oncolytic virus, Oncorine, was approved by Chinese SFDA in November 2005 for nasopharyngeal carcinoma combined with chemotherapy. Since then, a number of oncolytic viruses have been moved into clinical trials. Among these are the armed oncolytic adenoviruses such as H103 (expressing the heat shock protein) currently has finished phase I trial, and KH901 (expressing GM-CSF) now launched in phase II trial In this review, we will discuss the current status of ongoing oncolytic virus projects being conducted at various clinical stages in China, including the preliminary market response for Oncorine after it was launched into the Chinese market in 2006. PMID:21740357

  12. 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.

  13. CCL21/IL21-armed oncolytic adenovirus enhances antitumor activity against TERT-positive tumor cells.

    Science.gov (United States)

    Li, Yang; Li, Yi-Fei; Si, Chong-Zhan; Zhu, Yu-Hui; Jin, Yan; Zhu, Tong-Tong; Liu, Ming-Yuan; Liu, Guang-Yao

    2016-07-15

    Multigene-armed oncolytic adenoviruses are capable of efficiently generating a productive antitumor immune response. The chemokine (C-C motif) ligand 21 (CCL21) binds to CCR7 on naïve T cells and dendritic cells (DCs) to promote their chemoattraction to the tumor and resultant antitumor activity. Interleukin 21 (IL21) promotes survival of naïve T cells while maintaining their CCR7 surface expression, which increases their capacity to transmigrate in response to CCL21 chemoattraction. IL21 is also involved in NK cell differentiation and B cell activation and proliferation. The generation of effective antitumor immune responses is a complex process dependent upon coordinated interactions of various subsets of effector cells. Using the AdEasy system, we aimed to construct an oncolytic adenovirus co-expressing CCL21 and IL21 that could selectively replicate in TERTp-positive tumor cells (Ad-CCL21-IL21 virus). The E1A promoter of these oncolytic adenoviruses was replaced by telomerase reverse transcriptase promoter (TERTp). Ad-CCL21-IL21 was constructed from three plasmids, pGTE-IL21, pShuttle-CMV-CCL21 and AdEasy-1 and was homologously recombined and propagated in the Escherichia coli strain BJ5183 and the packaging cell line HEK-293, respectively. Our results showed that our targeted and armed oncolytic adenoviruses Ad-CCL21-IL21 can induce apoptosis in TERTp-positive tumor cells to give rise to viral propagation, in a dose-dependent manner. Importantly, we confirm that these modified oncolytic adenoviruses do not replicate efficiently in normal cells even under high viral loads. Additionally, we investigate the role of Ad-CCL21-IL21 in inducing antitumor activity and tumor specific cytotoxicity of CTLs in vitro. This study suggests that Ad-CCL21-IL21 is a promising targeted tumor-specific oncolytic adenovirus. PMID:27157859

  14. Oncolytic Virotherapy of Canine and Feline Cancer

    Directory of Open Access Journals (Sweden)

    Ivaylo Gentschev

    2014-05-01

    Full Text Available Cancer is the leading cause of disease-related death in companion animals such as dogs and cats. Despite recent progress in the diagnosis and treatment of advanced canine and feline cancer, overall patient treatment outcome has not been substantially improved. Virotherapy using oncolytic viruses is one promising new strategy for cancer therapy. Oncolytic viruses (OVs preferentially infect and lyse cancer cells, without causing excessive damage to surrounding healthy tissue, and initiate tumor-specific immunity. The current review describes the use of different oncolytic viruses for cancer therapy and their application to canine and feline cancer.

  15. Recombinant human deoxyribonuclease attenuates oxidative stress in a model of eosinophilic pulmonary response in mice.

    Science.gov (United States)

    da Cunha, Aline Andrea; Nuñez, Nailê Karine; de Souza, Rodrigo Godinho; Vargas, Mauro Henrique Moraes; Silveira, Josiane Silva; Antunes, Géssica Luana; Schmitz, Felipe; de Souza Wyse, Angela Terezinha; Jones, Marcus Herbert; Pitrez, Paulo Márcio

    2016-02-01

    The inflammatory cells infiltrating the airways produce several mediators, such as reactive oxygen species (ROS). ROS and the oxidant-antioxidant imbalance might play an important role in the modulation of airways inflammation. In order to avoid the undesirable effects of ROS, various endogenous antioxidant strategies have evolved, incorporating both enzymatic and non-enzymatic mechanisms. Recombinant human deoxyribonuclease (rhDNase) in clinical studies demonstrated a reduction in sputum viscosity, cleaving extracellular DNA in the airways, and facilitating mucus clearance, but an antioxidant effect was not studied so far. Therefore, we evaluated whether the administration of rhDNase improves oxidative stress in a murine model of asthma. Mice were sensitized by two subcutaneous injections of ovalbumin (OVA), on days 0 and 7, followed by three lung challenges with OVA on days 14, 15, and 16. On days 15 and 16, after 2 h of the challenge with OVA, mice received 1 mg/mL of rhDNase in the lungs. Bronchoalveolar lavage fluid and lung tissue were obtained on day 17, for inflammatory and oxidative stress analysis. We showed that rhDNase did not alter the population of inflammatory cells, such as eosinophil cells, in OVA-treated rhDNase group but significantly improved oxidative stress in lung tissue, by decreasing oxygen reactive species and increasing superoxide dismutase/catalase ratio, glutathione peroxidase activity, and thiol content. Our data provide the first evidence that rhDNase decreases some measures of oxidative stress and antioxidant status in a murine model of asthma, with a potential antioxidant effect to be further studied in human asthma. PMID:26738487

  16. Polymeric oncolytic adenovirus for cancer gene therapy.

    Science.gov (United States)

    Choi, Joung-Woo; Lee, Young Sook; Yun, Chae-Ok; Kim, Sung Wan

    2015-12-10

    Oncolytic adenovirus (Ad) vectors present a promising modality to treat cancer. Many clinical trials have been done with either naked oncolytic Ad or combination with chemotherapies. However, the systemic injection of oncolytic Ad in clinical applications is restricted due to significant liver toxicity and immunogenicity. To overcome these issues, Ad has been engineered physically or chemically with numerous polymers for shielding the Ad surface, accomplishing extended blood circulation time and reduced immunogenicity as well as hepatotoxicity. In this review, we describe and classify the characteristics of polymer modified oncolytic Ad following each strategy for cancer treatment. Furthermore, this review concludes with the highlights of various polymer-coated Ads and their prospects, and directions for future research. PMID:26453806

  17. Oncolytic Activities of Host Defense Peptides

    Directory of Open Access Journals (Sweden)

    Lars Steinstraesser

    2011-11-01

    Full Text Available Cancer continues to be a leading source of morbidity and mortality worldwide in spite of progress in oncolytic therapies. In addition, the incidence of cancers affecting the breast, kidney, prostate and skin among others continue to rise. Chemotherapeutic drugs are widely used in cancer treatment but have the serious drawback of nonspecific toxicity because these agents target any rapidly dividing cell without discriminating between healthy and malignant cells. In addition, many neoplasms eventually become resistant to conventional chemotherapy due to selection for multidrug-resistant variants. The limitations associated with existing chemotherapeutic drugs have stimulated the search for new oncolytic therapies. Host defense peptides (HDPs may represent a novel family of oncolytic agents that can avoid the shortcomings of conventional chemotherapy because they exhibit selective cytotoxicity against a broad spectrum of malignant human cells, including multi-drug-resistant neoplastic cells. Oncolytic activity by HDPs is usually via necrosis due to cell membrane lysis, but some HDPs can trigger apoptosis in cancer cells via mitochondrial membrane disruption. In addition, certain HDPs are anti-angiogenic which may inhibit cancer progression. This paper reviews oncolytic HDP studies in order to address the suitability of selected HDPs as oncolytic therapies.

  18. 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.

  19. Vaccination against canine distemper virus infection in infant ferrets with and without maternal antibody protection, using recombinant attenuated poxvirus vaccines.

    Science.gov (United States)

    Welter, J; Taylor, J; Tartaglia, J; Paoletti, E; Stephensen, C B

    2000-07-01

    Canine distemper virus (CDV) infection of ferrets is clinically and immunologically similar to measles, making this a useful model for the human disease. The model was used to determine if parenteral or mucosal immunization of infant ferrets at 3 and 6 weeks of age with attenuated vaccinia virus (NYVAC) or canarypox virus (ALVAC) vaccine strains expressing the CDV hemagglutinin (H) and fusion (F) protein genes (NYVAC-HF and ALVAC-HF) would induce serum neutralizing antibody and protect against challenge infection at 12 weeks of age. Ferrets without maternal antibody that were vaccinated parenterally with NYVAC-HF (n = 5) or ALVAC-HF (n = 4) developed significant neutralizing titers (log(10) inverse mean titer +/- standard deviation of 2.30 +/- 0.12 and 2.20 +/- 0.34, respectively) by the day of challenge, and all survived with no clinical or virologic evidence of infection. Ferrets without maternal antibody that were vaccinated intranasally (i.n.) developed lower neutralizing titers, with NYVAC-HF producing higher titers at challenge (1.11 +/- 0.57 versus 0.40 +/- 0.37, P = 0.02) and a better survival rate (6/7 versus 0/5, P = 0.008) than ALVAC-HF. Ferrets with maternal antibody that were vaccinated parenterally with NYVAC-HF (n = 7) and ALVAC-HF (n = 7) developed significantly higher antibody titers (1.64 +/- 0. 54 and 1.28 +/- 0.40, respectively) than did ferrets immunized with an attenuated CDV vaccine (0.46 +/- 0.59; n = 7) or the recombinant vectors expressing rabies glycoprotein (RG) (0.19 +/- 0.32; n = 8, P = 7 x 10(-6)). The NYVAC vaccine also protected against weight loss, and both the NYVAC and attenuated CDV vaccines protected against the development of some clinical signs of infection, although survival in each of the three vaccine groups was low (one of seven) and not significantly different from the RG controls (none of eight). Combined i.n.-parenteral immunization of ferrets with maternal antibody using NYVAC-HF (n = 9) produced higher titers (1

  20. 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.

  1. 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.

  2. 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

  3. 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

    2016-07-01

    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 will

  4. Attenuated recombinant vaccinia virus expressing oncofetal antigen (tumor-associated antigen) 5T4 induces active therapy of established tumors.

    Science.gov (United States)

    Mulryan, Kate; Ryan, Matthew G; Myers, Kevin A; Shaw, David; Wang, Who; Kingsman, Susan M; Stern, Peter L; Carroll, Miles W

    2002-10-01

    The human oncofetal antigen 5T4 (h5T4) is a transmembrane glycoprotein overexpressed by a wide spectrum of cancers, including colorectal, ovarian, and gastric, but with a limited normal tissue expression. Such properties make 5T4 an excellent putative target for cancer immunotherapy. The murine homologue of 5T4 (m5T4) has been cloned and characterized, which allows for the evaluation of immune intervention strategies in "self-antigen" in vivo tumor models. We have constructed recombinant vaccinia viruses based on the highly attenuated and modified vaccinia virus ankara (MVA strain), expressing h5T4 (MVA-h5T4), m5T4 (MVA-m5T4), and Escherichia coli LacZ (MVA-LacZ). Immunization of BALB/c and C57BL/6 mice with MVA-h5T4 and MVA-m5T4 constructs induced antibody responses to human and mouse 5T4, respectively. C57BL/6 and BALB/c mice vaccinated with MVA-h5T4 were challenged with syngeneic tumor line transfectants, B16 melanoma, and CT26 colorectal cells that express h5T4. MVA-h5T4-vaccinated mice showed significant tumor retardation compared with mice vaccinated with MVA-LacZ or PBS. In active treatment studies, inoculation with MVA-h5T4 was able to treat established CT26-h5T4 lung tumor and to a lesser extent B16.h5T4 s.c. tumors. Additionally, when C57BL/6 mice vaccinated with MVA-m5T4 were challenged with B16 cells expressing m5T4, resulting growth of the tumors was significantly retarded compared with control animals. Furthermore, mice vaccinated with MVA-m5T4 showed no signs of autoimmune toxicity. These data support the use of MVA-5T4 for tumor immunotherapy. PMID:12481437

  5. 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.

  6. Ocular infection of mice with an avirulent recombinant HSV-1 expressing IL-4 and an attenuated HSV-1 strain generates virulent recombinants in vivo

    OpenAIRE

    Mott, Kevin R; Wechsler, Steven L.; Ghiasi, Homayon

    2010-01-01

    Purpose To assess the relative impact of overexpression of interleukin 2 (IL-2), interleukin 4 (IL-4), and interferon gamma (IFN-γ) expressing recombinant herpes simplex virus type 1 (HSV-1) on altering immune responses in ocularly infected mice. Methods BALB/c mice were co-infected ocularly with avirulent HSV-1 strain KOS and avirulent recombinant HSV-1 expressing murine IL-4 (HSV-IL-4). Controls mice were co-infected with KOS + HSV-IL-2 or KOS + HSV-IFNγ. Following ocular infection, virus r...

  7. 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.

  8. The impact of hypoxia on oncolytic virotherapy

    Directory of Open Access Journals (Sweden)

    Guo ZS

    2011-11-01

    Full Text Available Z Sheng GuoUniversity of Pittsburgh Cancer Institute and Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, USAAbstract: The hypoxic tumor microenvironment plays significant roles in tumor cell metabolism and survival, tumor growth, and progression. Hypoxia modulates target genes in target cells mainly through an oxygen-sensing signaling pathway mediated by hypoxia-inducible factor of transcription factors. As a result, hypoxic tumor cells are resistant to conventional therapeutics such as radiation and chemotherapy. Oncolytic virotherapy may be a promising novel therapeutic for hypoxic cancer. Some oncolytic viruses are better adapted than others to the hypoxic tumor environment. Replication of adenoviruses from both groups B and C is inhibited, yet replication of herpes simplex virus is enhanced. Hypoxia seems to exert little or no effect on the replication of other oncolytic viruses. Vaccinia virus displayed increased cytotoxicity in some hypoxic cancer cells even though viral protein synthesis and transgene expression were not affected. Vesicular stomatitis virus replicated to similar levels in both hypoxic and normoxic conditions, and is effective for killing hypoxic cancer cells. However, vesicular stomatitis virus and reovirus, but not encephalomyocarditis virus, are sensitive to elevated levels of hypoxia-inducible factor-1α in renal cancer cells with the loss of von Hippel–Lindau tumor suppressor protein, because elevated hypoxia-inducible factor activity confers dramatically enhanced resistance to cytotoxicity mediated by vesicular stomatitis virus or reovirus. A variety of hypoxia-selective and tumor-type-specific oncolytic adenoviruses, generated by incorporating hypoxia-responsive elements into synthetic promoters to control essential genes for viral replication or therapeutic genes, have been shown to be safe and efficacious. Hypoxic tumor-homing macrophages can function effectively as carrier

  9. Cell carriers for oncolytic viruses: current challenges and future directions.

    Science.gov (United States)

    Roy, Dominic G; Bell, John C

    2013-01-01

    The optimal route for clinical delivery of oncolytic viruses is thought to be systemic intravenous injection; however, the immune system is armed with several highly efficient mechanisms to remove pathogens from the circulatory system. To overcome the challenges faced in trying to delivery oncolytic viruses specifically to tumors via the bloodstream, carrier cells have been investigated to determine their suitability as delivery vehicles for systemic administration of oncolytic viruses. Cell carriers protect viruses from neutralization, one of the most limiting aspects of oncolytic virus interaction with the immune system. Cell carriers can also possess inherent tumor tropism, thus directing the delivery of the virus more specifically to a tumor. With preclinical studies already demonstrating the success and feasibility of this approach with multiple oncolytic viruses, clinical evaluation of cell-mediated delivery of viruses is on the horizon. Meanwhile, ongoing preclinical studies are aimed at identifying new cellular vehicles for oncolytic viruses and improving current promising cell carrier platforms. PMID:27512657

  10. Proteasome Inhibition Is Partially Effective in Attenuating Pre-Existing Immunity against Recombinant Adeno-Associated Viral Vectors

    OpenAIRE

    Karman, Jozsef; Gumlaw, Nathan K; Zhang, Jinhua; Jiang, Ji-Lei; Cheng, Seng H.; Zhu, Yunxiang

    2012-01-01

    Pre-existing immunity against adeno-associated virus (AAV) remains a major challenge facing the clinical use of systemic administration of recombinant AAV vectors for the treatment of genetic and acquired diseases using gene therapy. In this study, we evaluated the potential of bortezomib (marketed under trade name Velcade) to abrogate a pre-existing immunity to AAV in mice, thereby allowing subsequent transduction by a recombinant AAV vector of the same serotype. We demonstrate that bortezom...

  11. Immunocompetent syngeneic cotton rat tumor models for the assessment of replication-competent oncolytic adenovirus

    International Nuclear Information System (INIS)

    Oncolytic adenoviruses as a treatment for cancer have demonstrated limited clinical activity. Contributing to this may be the relevance of preclinical animal models used to study these agents. Syngeneic mouse tumor models are generally non-permissive for adenoviral replication, whereas human tumor xenograft models exhibit attenuated immune responses to the vector. The cotton rat (Sigmodon hispidus) is susceptible to human adenovirus infection, permissive for viral replication and exhibits similar inflammatory pathology to humans with adenovirus replicating in the lungs, respiratory passages and cornea. We evaluated three transplantable tumorigenic cotton rat cell lines, CCRT, LCRT and VCRT as models for the study of oncolytic adenoviruses. All three cells lines were readily infected with adenovirus type-5-based vectors and exhibited high levels of transgene expression. The cell lines supported viral replication demonstrated by the induction of cytopathogenic effect (CPE) in tissue culture, increase in virus particle numbers and assembly of virions seen on transmission electron microscopy. In vivo, LCRT and VCRT tumors demonstrated delayed growth after injection with replicating adenovirus. No in vivo antitumor activity was seen in CCRT tumors despite in vitro oncolysis. Adenovirus was also rapidly cleared from the CCRT tumors compared to LCRT and VCRT tumors. The effect observed with the different cotton rat tumor cell lines mimics the variable results of human clinical trials highlighting the potential relevance of this model for assessing the activity and toxicity of oncolytic adenoviruses

  12. 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. PMID:26803055

  13. Negative Regulation-Resistant p53 Variant Enhances Oncolytic Adenoviral Gene Therapy

    OpenAIRE

    Koo, Taeyoung; Choi, Il-Kyu; Kim, Minjung; Lee, Jung-Sun; Oh, Eonju; Kim, Jungho; Yun, Chae-Ok

    2012-01-01

    Intact p53 function is essential for responsiveness to cancer therapy. However, p53 activity is attenuated by the proto-oncoprotein Mdm2, the adenovirus protein E1B 55kD, and the p53 C-terminal domain. To confer resistance to Mdm2, E1B 55kD, and C-terminal negative regulation, we generated a p53 variant (p53VPΔ30) by deleting the N-terminal and C-terminal regions of wild-type p53 and inserting the transcriptional activation domain of herpes simplex virus VP16 protein. The oncolytic adenovirus...

  14. 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

  15. 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

  16. Immunotherapeutic Potential of Oncolytic Vaccinia Virus

    Directory of Open Access Journals (Sweden)

    StephenThorne

    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.

  17. Improving delivery of oncolytic viruses to solid tumours

    Czech Academy of Sciences Publication Activity Database

    Carlisle, R.; Mo, S.; Myers, R.; Graham, S.; Laga, Richard; Ulbrich, Karel; Coussios, C.; Seymour, L.

    MARY ANN LIEBERT INC. Roč. 25, č. 12 (2014), A4-A5. ISSN 1043-0342. [International Conference on Oncolytic Virus Therapeutics /8./. 10.04.2014-13.04.2014, Oxford] Institutional support: RVO:61389013 Keywords : oncolytic virus es * solid tumours Subject RIV: CD - Macromolecular Chemistry

  18. Vaccination against Canine Distemper Virus Infection in Infant Ferrets with and without Maternal Antibody Protection, Using Recombinant Attenuated Poxvirus Vaccines

    OpenAIRE

    Welter, Janet; Taylor, Jill; Tartaglia, James; Paoletti, Enzo; Stephensen, Charles B.

    2000-01-01

    Canine distemper virus (CDV) infection of ferrets is clinically and immunologically similar to measles, making this a useful model for the human disease. The model was used to determine if parenteral or mucosal immunization of infant ferrets at 3 and 6 weeks of age with attenuated vaccinia virus (NYVAC) or canarypox virus (ALVAC) vaccine strains expressing the CDV hemagglutinin (H) and fusion (F) protein genes (NYVAC-HF and ALVAC-HF) would induce serum neutralizing antibody and protect agains...

  19. 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. PMID:23171359

  20. Cell carriers for oncolytic viruses: current challenges and future directions

    Directory of Open Access Journals (Sweden)

    Roy DG

    2013-10-01

    Full Text Available Dominic G Roy,1,2 John C Bell1–31Centre for Innovative Cancer Therapeutics, Ottawa Hospital Research Institute, 2Department of Biochemistry, Immunology and Microbiology, 3Department of Medicine, University of Ottawa, Ottawa, ON, CanadaAbstract: The optimal route for clinical delivery of oncolytic viruses is thought to be systemic intravenous injection; however, the immune system is armed with several highly efficient mechanisms to remove pathogens from the circulatory system. To overcome the challenges faced in trying to delivery oncolytic viruses specifically to tumors via the bloodstream, carrier cells have been investigated to determine their suitability as delivery vehicles for systemic administration of oncolytic viruses. Cell carriers protect viruses from neutralization, one of the most limiting aspects of oncolytic virus interaction with the immune system. Cell carriers can also possess inherent tumor tropism, thus directing the delivery of the virus more specifically to a tumor. With preclinical studies already demonstrating the success and feasibility of this approach with multiple oncolytic viruses, clinical evaluation of cell-mediated delivery of viruses is on the horizon. Meanwhile, ongoing preclinical studies are aimed at identifying new cellular vehicles for oncolytic viruses and improving current promising cell carrier platforms.Keywords: oncolytic virus, cell carrier, systemic delivery, tumor targeting, cancer

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

    Directory of Open Access Journals (Sweden)

    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.

  2. Ad 2.0: a novel recombineering platform for high-throughput generation of tailored adenoviruses

    OpenAIRE

    Mück-Häusl, Martin; Solanki, Manish; Zhang, Wenli; Ruzsics, Zsolt; Ehrhardt, Anja

    2015-01-01

    Recombinant adenoviruses containing a double-stranded DNA genome of 26–45 kb were broadly explored in basic virology, for vaccination purposes, for treatment of tumors based on oncolytic virotherapy, or simply as a tool for efficient gene transfer. However, the majority of recombinant adenoviral vectors (AdVs) is based on a small fraction of adenovirus types and their genetic modification. Recombineering techniques provide powerful tools for arbitrary engineering of recombinant DNA. Here, we ...

  3. Live recombinant BHV/BRSV vaccine

    NARCIS (Netherlands)

    Keil, G.M.; Rijsewijk, F.A.M.

    1998-01-01

    The present invention refers to synthetic Bovine Respiratory Syncytium virus genes. Also the invention relates to live attenuated Bovine Herpesvirus recombinants carrying such synthetic genes. Furthermore, the invention relates to vaccines based on these live attenuated recombinants, for the protect

  4. Protection induced by commercially available live-attenuated and recombinant viral vector vaccines against infectious laryngotracheitis virus in broiler chickens.

    Science.gov (United States)

    Vagnozzi, Ariel; Zavala, Guillermo; Riblet, Sylva M; Mundt, Alice; García, Maricarmen

    2012-01-01

    Viral vector vaccines using fowl poxvirus (FPV) and herpesvirus of turkey (HVT) as vectors and carrying infectious laryngotracheitis virus (ILTV) genes are commercially available to the poultry industry in the USA. Different sectors of the broiler industry have used these vaccines in ovo or subcutaneously, achieving variable results. The objective of the present study was to determine the efficacy of protection induced by viral vector vaccines as compared with live-attenuated ILTV vaccines. The HVT-LT vaccine was more effective than the FPV-LT vaccine in mitigating the disease and reducing levels of challenge virus when applied in ovo or subcutaneously, particularly when the challenge was performed at 57 days rather than 35 days of age. While the FPV-LT vaccine mitigated clinical signs more effectively when administered subcutaneously than in ovo, it did not reduce the concentration of challenge virus in the trachea by either application route. Detection of antibodies against ILTV glycoproteins expressed by the viral vectors was a useful criterion to assess the immunogenicity of the vectors. The presence of glycoprotein I antibodies detected pre-challenge and post challenge in chickens vaccinated with HVT-LT indicated that the vaccine induced a robust antibody response, which was paralleled by significant reduction of clinical signs. The chicken embryo origin vaccine provided optimal protection by significantly mitigating the disease and reducing the challenge virus in chickens vaccinated via eye drop. The viral vector vaccines, applied in ovo and subcutaneously, provided partial protection, reducing to some degree clinical signs, and challenge VIRUS replication in the trachea. PMID:22845318

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

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  7. Recombinant human brain natriuretic peptide attenuates LPS-induced cellular injury in human fetal lung fibroblasts via inhibiting MAPK and NF-κB pathway activation.

    Science.gov (United States)

    Song, Zhi; Zhao, Xiu; Liu, Martin; Jin, Hongxu; Cui, Yan; Hou, Mingxiao; Gao, Yan

    2016-08-01

    Inflammatory responses are vital in lung injury diseases, particularly acute respiratory distress syndrome (ARDS). Recombinant human brain natriuretic peptide (rhBNP) has been shown to exhibit anti‑inflammatory effects in vivo in our previous studies. The present study aimed to investigate the mechanisms underlying the anti‑inflammatory effects of rhBNP on lipopolysaccharide (LPS)-induced human fetal lung fibroblasts (HFL-1). The results showed that LPS induced a significant increase in the leakage of lactate dehydrogenase and the secretion of interleukin (IL)‑1β. Activation of p38, extracellular-signal regulated kinase (ERK) 1/2, c‑Jun NH2-terminal kinase (JNK) mitogen‑activated protein kinases (MAPK)s, and nuclear factor (NF)‑κB in HFL‑1 cells was also observed following treatment with LPS. Treatment with rhBNP (0.1 µM) reduced the production of IL‑1β at the protein and mRNA levels. Moreover, rhBNP decreased the phosphorylation of p38, ERK1/2 and JNK induced by LPS. However, the JNK inhibitor, SP600125, significantly inhibited LPS‑induced IL‑1β production. These results indicate that the inhibition of IL‑1β by may dependent upon the JNK signaling pathway. The LPS‑induced NF‑κB activation was also suppressed by rhBNP, and IL‑1β production was inhibited by the NF‑κB inhibitor. Furthermore, NF‑κB activation was attenuated by the JNK inhibitor, indicating that NF‑κB activation was dependent on the JNK signaling pathway. The present study suggests that rhBNP exhibits an anti‑inflammatory effect on LPS‑induced HFL‑1 cell injury via the inhibition of MAPK and NF‑κB signaling pathways and may exhibit therapeutic potential for acute lung injury and ARDS. PMID:27314600

  8. Efficacy and safety of oncolytic vaccinia virus and Semliki Forest virus in the treatment of canine and feline malignant tumours

    OpenAIRE

    Autio, Karoliina

    2015-01-01

    Cancer is one of the most common reasons for death in dogs, cats and humans. New therapeutic modalities are necessary to improve disease outcome. One promising approach is oncolytic virotherapy. Until now, the only oncolytic virus evaluated in a clinical trial in veterinary medicine has been canine oncolytic adenovirus, but a clinical trial has been started with oncolytic vaccinia virus (VV) in pet dogs. In cats, oncolytic viruses have not been evaluated in clinical settings. Tumour treatment...

  9. Oncolytic virotherapy for human malignant mesothelioma: recent advances

    Directory of Open Access Journals (Sweden)

    Boisgerault N

    2015-09-01

    Full Text Available Nicolas Boisgerault,1–3 Carole Achard,1–3 Tiphaine Delaunay,1–3 Laurent Cellerin,4 Frédéric Tangy,5 Marc Grégoire,1–3 Jean-François Fonteneau1–31INSERM, UMR892, 2CNRS, UMR6299, Health Research Institute of the University of Nantes, 3University of Nantes, 4Nantes CHU Hospital, Department of Thoracic and Digestive Oncology, 5Viral Genomics and Vaccination Unit, Institut Pasteur, Paris, CNRS UMR-3569, FranceAbstract: Cancer virotherapy is an attractive alternative to conventional treatments because it offers a wide range of antitumor effects due to 1 the diversity of the oncolytic viruses that are now available and 2 their multifaceted activities against both tumor cells and tumor vessels, in addition to their ability to induce antitumor immune responses. In this review, we summarize preclinical and clinical data regarding the targeting of malignant mesothelioma (MM by oncolytic viruses. We also discuss the potential of other oncolytic viruses that have already shown antitumor effects against several malignancies in advanced clinical trials but are yet to be tested against MM cells. Finally, we review how the activation of the immune system and combinations with other types of anticancer treatments could support the development of oncolytic virotherapy for the treatment of MM.Keywords: oncolytic viruses, cancer virotherapy, malignant mesothelioma, antitumor immune responses, immunotherapy

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

    Directory of Open Access Journals (Sweden)

    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.

  11. Exploiting tumor epigenetics to improve oncolytic virotherapy

    Directory of Open Access Journals (Sweden)

    Nicole E. Forbes

    2013-09-01

    Full Text Available Oncolytic viruses (OVs comprise a versatile and multi-mechanistic therapeutic platform in the growing arsenal of anticancer biologics. These replicating therapeutics find favorable conditions in the tumor niche, characterized among others by increased metabolism, reduced anti-tumor/antiviral immunity, and disorganized vasculature. Through a self-amplification that is dependent on multiple cancer-specific defects, these agents exhibit remarkable tumor selectivity. With several OVs completing or entering Phase III clinical evaluation, their therapeutic potential as well as the challenges ahead are increasingly clear. One key hurdle is tumor heterogeneity, which results in variations in the ability of tumors to support productive infection by OVs and to induce adaptive anti-tumor immunity. To this end, mounting evidence suggests tumor epigenetics may play a key role. This review will focus on the epigenetic landscape of tumors and how it relates to OV infection. Therapeutic strategies aiming to exploit the epigenetic identity of tumors in order to improve OV therapy are also discussed.

  12. Recombinant Newcastle disease virus expressing IL15 demonstrates promising antitumor efficiency in melanoma model

    Science.gov (United States)

    Recombinant Newcastle Disease Virus (rNDV) has shown oncolytic therapeutic effect in preclinical studies. Previous data indicate that rNDV carrying IL2 has shown promise in cancer therapy. Due to the significant side effects of IL2, IL15 has been introduced into cancer therapy. A number of studies h...

  13. Big Data Offers Novel Insights for Oncolytic Virus Immunotherapy

    Directory of Open Access Journals (Sweden)

    Stephanie L. Swift

    2016-02-01

    Full Text Available 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.

  14. Big Data Offers Novel Insights for Oncolytic Virus Immunotherapy.

    Science.gov (United States)

    Swift, Stephanie L; Stojdl, David F

    2016-02-01

    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

  15. Big Data Offers Novel Insights for Oncolytic Virus Immunotherapy

    Science.gov (United States)

    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

  16. Cancer immunotherapy via combining oncolytic virotherapy with chemotherapy: recent advances

    Directory of Open Access Journals (Sweden)

    Simpson GR

    2016-01-01

    Full Text Available Guy R Simpson,1 Kate Relph,1 Kevin Harrington,2 Alan Melcher,3 Hardev Pandha1 1Department of Clinical and Experimental Medicine, Targeted Cancer Therapy, Faculty of Health and Medical Sciences, University of Surrey, Guildford, 2Targeted Therapy, The Institute of Cancer Research/The Royal Marsden NIHR Biomedical Research Centre, London, 3Targeted and Biological Therapies,Oncology and Clinical Research, Leeds Institute of Cancer and Pathology, Faculty of Medicine and Health, University of Leeds, Leeds, UK Abstract: Oncolytic viruses are multifunctional anticancer agents with huge clinical potential, and have recently passed the randomized Phase III clinical trial hurdle. Both wild-type and engineered viruses have been selected for targeting of specific cancers, to elicit cytotoxicity, and also to generate antitumor immunity. Single-agent oncolytic virotherapy treatments have resulted in modest effects in the clinic. There is increasing interest in their combination with cytotoxic agents, radiotherapy and immune-checkpoint inhibitors. Similarly to oncolytic viruses, the benefits of chemotherapeutic agents may be that they induce systemic antitumor immunity through the induction of immunogenic cell death of cancer cells. Combining these two treatment modalities has to date resulted in significant potential in vitro and in vivo synergies through various mechanisms without any apparent additional toxicities. Chemotherapy has been and will continue to be integral to the management of advanced cancers. This review therefore focuses on the potential for a number of common cytotoxic agents to be combined with clinically relevant oncolytic viruses. In many cases, this combined approach has already advanced to the clinical trial arena. Keywords: oncolytic virotherapy, chemotherapy, immunogenic cell death

  17. Immune cells: more than simple carriers for systemic delivery of oncolytic viruses

    Directory of Open Access Journals (Sweden)

    Eisenstein S

    2014-11-01

    Full Text Available Samuel Eisenstein,1 Shu-Hsia Chen,2 Ping-Ying Pan21Department of Surgery, 2Department of Oncological Sciences and Tisch Cancer Institute, The Icahn School of Medicine at Mount Sinai, New York, NY, USAAbstract: Oncolytic virotherapy on its own has numerous drawbacks, including an inability of the virus to actively target tumor cells and systemic toxicities at the high doses necessary to effectively treat tumors. Addition of immune cell-based carriers of oncolytic viruses holds promise as a technique in which oncolytic virus can be delivered directly to tumors in smaller and less toxic doses. Interestingly, the cell carriers themselves have also demonstrated antitumor effects, which can be augmented further by tailoring the appropriate oncolytic virus to the appropriate cell type. This review discusses the multiple factors that go into devising an effective, cell-based delivery system for oncolytic viruses.Keywords: oncolytic virus, cell carrier, immune cells, cancer therapy, myeloid-derived suppressor cells

  18. Development of a Recombinant Epsilon Toxoid Vaccine against Enterotoxemia and Its Use as a Combination Vaccine with Live Attenuated Sheep Pox Virus against Enterotoxemia and Sheep Pox▿

    OpenAIRE

    Chandran, Dev; Naidu, Sureddi Satyam; Sugumar, Parthasarathy; Rani, Gudavalli Sudha; Vijayan, Shahana Pallichera; Mathur, Deepika; Garg, Lalit C; Srinivasan, Villuppanoor Alwar

    2010-01-01

    Sheep pox and enterotoxemia are important diseases of sheep, and these diseases cause severe economic losses to sheep farmers. The present study was undertaken to evaluate the potential of formaldehyde-inactivated recombinant epsilon toxin as a vaccine candidate. The potency of the recombinant epsilon toxoid with aluminum hydroxide as an adjuvant in sheep was determined. Vaccinated sheep were protected against enterotoxemia, with potency values of >5 IU being protective. Further, the use of t...

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Development of a recombinant epsilon toxoid vaccine against enterotoxemia and its use as a combination vaccine with live attenuated sheep pox virus against enterotoxemia and sheep pox.

    Science.gov (United States)

    Chandran, Dev; Naidu, Sureddi Satyam; Sugumar, Parthasarathy; Rani, Gudavalli Sudha; Vijayan, Shahana Pallichera; Mathur, Deepika; Garg, Lalit C; Srinivasan, Villuppanoor Alwar

    2010-06-01

    Sheep pox and enterotoxemia are important diseases of sheep, and these diseases cause severe economic losses to sheep farmers. The present study was undertaken to evaluate the potential of formaldehyde-inactivated recombinant epsilon toxin as a vaccine candidate. The potency of the recombinant epsilon toxoid with aluminum hydroxide as an adjuvant in sheep was determined. Vaccinated sheep were protected against enterotoxemia, with potency values of >5 IU being protective. Further, the use of this construct in a combination vaccine against sheep pox resulted in the sheep being protected against both sheep pox and enterotoxemia. PMID:20427629

  1. Development of a Recombinant Epsilon Toxoid Vaccine against Enterotoxemia and Its Use as a Combination Vaccine with Live Attenuated Sheep Pox Virus against Enterotoxemia and Sheep Pox▿

    Science.gov (United States)

    Chandran, Dev; Naidu, Sureddi Satyam; Sugumar, Parthasarathy; Rani, Gudavalli Sudha; Vijayan, Shahana Pallichera; Mathur, Deepika; Garg, Lalit C.; Srinivasan, Villuppanoor Alwar

    2010-01-01

    Sheep pox and enterotoxemia are important diseases of sheep, and these diseases cause severe economic losses to sheep farmers. The present study was undertaken to evaluate the potential of formaldehyde-inactivated recombinant epsilon toxin as a vaccine candidate. The potency of the recombinant epsilon toxoid with aluminum hydroxide as an adjuvant in sheep was determined. Vaccinated sheep were protected against enterotoxemia, with potency values of >5 IU being protective. Further, the use of this construct in a combination vaccine against sheep pox resulted in the sheep being protected against both sheep pox and enterotoxemia. PMID:20427629

  2. Immunostimulatory Gene Therapy Using Oncolytic Viruses as Vehicles.

    Science.gov (United States)

    Loskog, Angelica

    2015-11-01

    Immunostimulatory gene therapy has been developed during the past twenty years. The aim of immunostimulatory gene therapy is to tilt the suppressive tumor microenvironment to promote anti-tumor immunity. Hence, like a Trojan horse, the gene vehicle can carry warriors and weapons into enemy territory to combat the tumor from within. The most promising immune stimulators are those activating and sustaining Th1 responses, but even if potent effects were seen in preclinical models, many clinical trials failed to show objective responses in cancer patients. However, with new tools to control ongoing immunosuppression in cancer patients, immunostimulatory gene therapy is now emerging as an interesting option. In parallel, oncolytic viruses have been shown to be safe in patients. To prolong immune stimulation and to increase efficacy, these two fields are now merging and oncolytic viruses are armed with immunostimulatory transgenes. These novel agents are racing towards approval as established cancer immunotherapeutics. PMID:26561829

  3. Immunostimulatory Gene Therapy Using Oncolytic Viruses as Vehicles

    Directory of Open Access Journals (Sweden)

    Angelica Loskog

    2015-11-01

    Full Text Available Immunostimulatory gene therapy has been developed during the past twenty years. The aim of immunostimulatory gene therapy is to tilt the suppressive tumor microenvironment to promote anti-tumor immunity. Hence, like a Trojan horse, the gene vehicle can carry warriors and weapons into enemy territory to combat the tumor from within. The most promising immune stimulators are those activating and sustaining Th1 responses, but even if potent effects were seen in preclinical models, many clinical trials failed to show objective responses in cancer patients. However, with new tools to control ongoing immunosuppression in cancer patients, immunostimulatory gene therapy is now emerging as an interesting option. In parallel, oncolytic viruses have been shown to be safe in patients. To prolong immune stimulation and to increase efficacy, these two fields are now merging and oncolytic viruses are armed with immunostimulatory transgenes. These novel agents are racing towards approval as established cancer immunotherapeutics.

  4. HSF1 overexpression enhances oncolytic effect of replicative adenovirus

    Directory of Open Access Journals (Sweden)

    Deng Youwen

    2010-05-01

    Full Text Available Abstract Background E1B55kD deleted oncolytic adenovirus was designed to achieve cancer-specific cytotoxicity, but showed limitations in clinical study. To find a method to increase its efficacy, we investigated the correlation between oncolytic effect of such oncolytic adenovirus Adel55 and intracellular heat shock transcription factor 1 (HSF1 activity. Methods In the present study, human breast cancer cell line Bcap37 was stably transfected with constitutively active HSF1 (cHSF1 or HSF1 specific siRNA (HSF1i to establish increased or decreased HSF1 expression levels. Cytotoxicity of Adel55 was analyzed in these cell lines in vitro and in vivo. Furthermore, Adel55 incorporated with cHSF1 (Adel55-cHSF1 was used to treat various tumor xenografts. Results Adel55 could achieve more efficient oncolysis in cHSF1 transfected Bcap37 cells, both in vitro and in vivo. However, inhibition of HSF1 expression by HSF1i could rescue Bcap37 cell line from oncolysis by Adel55. A time course study of viral replication established a correlation between higher replication of Adel55 and cytolysis or tumor growth inhibition. Then, we constructed Adel55-cHSF1 for tumor gene therapy and demonstrated that it is more potent than Adel55 itself in oncolysis and replication in both Bcap37 and SW620 xenografts. Conclusions cHSF1 enhances the Adel55 cell-killing potential through increasing the viral replication and is a potential therapeutic implication to augment the potential of E1B55kD deleted oncolytic adenovirus by increasing its burst.

  5. Herpes Simplex Virus Oncolytic Therapy for Pediatric Malignancies

    OpenAIRE

    Friedman, Gregory K.; Pressey, Joseph G.; Reddy, Alyssa T.; Markert, James M.; Gillespie, G. Yancey

    2009-01-01

    Despite improving survival rates for children with cancer, a subset of patients exist with disease resistant to traditional therapies such as surgery, chemotherapy, and radiation. These patients require newer, targeted treatments used alone or in combination with more traditional approaches. Oncolytic herpes simplex virus (HSV) is one of these newer therapies that offer promise for several difficult to treat pediatric malignancies. The potential benefit of HSV therapy in pediatric solid tumor...

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

    OpenAIRE

    Morris, Don G.; Thirukkumaran, Chandini M.

    2011-01-01

    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 an...

  7. Big Data Offers Novel Insights for Oncolytic Virus Immunotherapy

    OpenAIRE

    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 funct...

  8. Modelling Spread of Oncolytic Viruses in Heterogeneous Cell Populations

    Science.gov (United States)

    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.

  9. Oncolytic Replication of E1b-Deleted Adenoviruses

    Directory of Open Access Journals (Sweden)

    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.

  10. Expression of Interferon Gamma by a Recombinant Rabies Virus Strongly Attenuates the Pathogenicity of the Virus via Induction of Type I Interferon

    OpenAIRE

    Barkhouse, Darryll A.; Garcia, Samantha A.; Bongiorno, Emily K.; Lebrun, Aurore; Faber, Milosz; Hooper, D. Craig

    2014-01-01

    Previous animal model experiments have shown a correlation between interferon gamma (IFN-γ) expression and both survival from infection with attenuated rabies virus (RABV) and reduction of neurological sequelae. Therefore, we hypothesized that rapid production of murine IFN-γ by the rabies virus itself would induce a more robust antiviral response than would occur naturally in mice. To test this hypothesis, we used reverse engineering to clone the mouse IFN-γ gene into a pathogenic rabies vir...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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

  13. Recombinant, Live-Attenuated Tetravalent Dengue Virus Vaccine Formulations Induce a Balanced, Broad, and Protective Neutralizing Antibody Response against Each of the Four Serotypes in Rhesus Monkeys

    OpenAIRE

    Blaney, Joseph E.; Matro, Jennifer M.; Murphy, Brian R.; Whitehead, Stephen S

    2005-01-01

    Three tetravalent vaccine (TV) formulations of previously described monovalent dengue (DEN) virus vaccine candidates were compared to a tetravalent formulation of wild-type DEN viruses (T-wt) for replication in SCID mice transplanted with human liver cells (SCID-HuH-7) or for replication and immunogenicity in rhesus monkeys. TV-1 consists of recombinant DEN1, -2, -3, and -4, each with a 30-nucleotide deletion in the 3′ untranslated region (Δ30). TV-2 consists of rDEN1Δ30, rDEN4Δ30, and two an...

  14. Delivery of oncolytic adenovirus into the nucleus of tumorigenic cells by tumor microparticles for virotherapy.

    Science.gov (United States)

    Ran, Li; Tan, Xiaohua; Li, Yanchun; Zhang, Huafeng; Ma, Ruihua; Ji, Tiantian; Dong, Wenqian; Tong, Tong; Liu, Yuying; Chen, Degao; Yin, Xiaonan; Liang, Xiaoyu; Tang, Ke; Ma, Jingwei; Zhang, Yi; Cao, Xuetao; Hu, Zhuowei; Qin, Xiaofeng; Huang, Bo

    2016-05-01

    Oncolytic viruses have been utilized for the treatment of various cancers. However, delivery of the viral particles to tumor cells remains a major challenge. Microparticles (MP) are vesicle forms of plasma membrane fragments of 0.1-1 μm in size that are shed by cells. We have previously shown the delivery of chemotherapeutic drugs using tumor cell-derived MPs (T-MP). Here we report that T-MPs can be utilized as a unique carrier system to deliver oncolytic adenoviruses to human tumors, leading to highly efficient cytolysis of tumor cells needed for in vivo treatment efficacy. This T-MP-mediated oncolytic virotherapy approach holds multiple advantages, including: 1) delivery of oncolytic adenovirus by T-MPs is able to avoid the antiviral effect of host antibodies; 2) delivery of oncolytic adenovirus by T-MPs is not limited by virus-specific receptor that mediates the entry of virus into tumor cells; 3) T-MPs are apt at delivering oncolytic adenoviruses to the nucleus of tumor cells as well as to stem-like tumor-repopulating cells for the desired purpose of killing them. These findings highlight a novel oncolytic adenovirus delivery system with highly promising clinical applications. PMID:26950165

  15. Combined use of chemotherapeutics and oncolytic adenovirus in treatment of AFP-expressing hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Chen-Yu Mao; Han-Ju Hua; Ping Chen; De-Chao Yu; Jiang Cao; Li-Song Teng

    2009-01-01

    BACKGROUND: Hepatocellular carcinoma (HCC) which is always refractory to most chemotherapeutic agents may result in poor survival of patients with advanced HCC. Oncolytic adenovirus is a new form for cancer gene therapy via its ability to replicate and kill tumor cells in a tumor-speciifc manner. In order to eradicate tumors effectively, the combination of chemotherapeutic agents and oncolytic adenovirus has been considered. This study aimed to systematically analyze the possibility of synergistic cytotoxicity of oncolytic adenoviruses in combination with chemotherapeutic agents. METHODS: Several types of human HCC cell lines were used to determine the speciifcity and cytotoxicity of oncolytic adenovirus Ad5-HC and Ad5-AFP (IRES) by measuring cell viabilityin vitro and antitumor efifciency in vivo. The cytotoxicity of Ad5-HC and Ad5-AFP (IRES) combined with chemotherapeutic agents were also assessed by the methyl thiazolyl tetrazolium assay. RESULTS: Both Ad5-HC and Ad5-AFP (IRES) were signiifcantly cytotoxic to HCC cells with great speciifcity in vitro andin vivo. The combination of oncolytic adenovirus with 5-FU, doxorubicin, and paclitaxel was synergistically effective for the killing of HCC cells. CONCLUSIONS: These data suggest that oncolytic adenovirus sensitize tumors to chemotherapy and the combination therapy of chemotherapeutic agents and oncolytic adenovirus has an enhanced antitumor effect on HCC cells.

  16. All reovirus subtypes show oncolytic potential in primary cells of human high-grade glioma.

    Science.gov (United States)

    Alloussi, S H; Alkassar, M; Urbschat, S; Graf, N; Gärtner, B

    2011-09-01

    Reoviridae are non-human pathogenic viruses. The family of reoviridae consists of 4 different subtypes. Many studies have proven that the Dearing subtype 3 has oncolytic potential. This potential is related to the RAS protein expression in tumour cells. The aim of this study, was to investigate whether all reovirus subtypes have oncolytic potential and whether there are differences in their efficacy, in particular for high-grade glioma. To evaluate the oncolytic potential, we performed an in vitro head-to-head study for all reovirus subtypes in 5 primary cell cultures of high-grade gliomas. The oncolytic activity was determined using end-point titration with observation of the cytopathogenic effect. For measurement of RAS activity, we performed an immunofluorescent detection stain on all cell cultures. For quantification of the virus, an RT-PCR measurement for all subtypes was performed. All reovirus subtypes showed oncolytic activity in the observed glioma biopsies. These observations correlated with RAS overexpression in the observed cells. All glioma biopsies overexpressed the RAS protein. The quantitative oncolytic potential differed in relation to the single observed cell culture and in relation to the chosen reovirus subtype. To our knowledge, this is the first study showing oncolytic activity for all reovirus subtypes. We show the relationship and correlation between RAS protein overexpression and vulnerability of cells to reovirus. Efficacy of the different subtypes is interindividually different and cannot be forecast. PMID:21637921

  17. 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

  18. Preclinical Mouse Models for Analysis of the Therapeutic Potential of Engineered Oncolytic Herpes Viruses.

    Science.gov (United States)

    Speranza, Maria-Carmela; Kasai, Kazue; Lawler, Sean E

    2016-03-31

    After more than two decades of research and development, oncolytic herpes viruses (oHSVs) are moving into the spotlight due to recent encouraging clinical trial data. oHSV and other oncolytic viruses function through direct oncolytic cancer cell-killing mechanisms and by stimulating antitumor immunity. As further viruses are developed and optimized for the treatment of various types of cancer, appropriate predictive preclinical models will be of great utility. This review will discuss existing data in this area, focusing on the mouse tumor models that are commonly used. PMID:27034396

  19. 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

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

    Directory of Open Access Journals (Sweden)

    GregoryKFriedman

    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.

  1. Update on oncolytic viral therapy – targeting angiogenesis

    Directory of Open Access Journals (Sweden)

    Tysome JR

    2013-07-01

    Full Text Available James R Tysome,1–3 Nick R Lemoine,1,3 Yaohe Wang1,31Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom; 2Department of Otolaryngology, Cambridge University Hospitals, Cambridge, United Kingdom; 3Sino-British Research Center for Molecular Oncology, Zhengzhou University, Zhengzhou, People's Republic of ChinaAbstract: Oncolytic viruses (OVs have the ability to selectively replicate in and lyse cancer cells. Angiogenesis is an essential requirement for tumor growth. Like OVs, the therapeutic effect of many angiogenesis inhibitors has been limited, leading to the development of more effective approaches to combine antiangiogenic therapy with OVs. Angiogenesis can be targeted either directly by OV infection of vascular endothelial cells, or by arming OVs with antiangiogenic transgenes, which are subsequently expressed locally in the tumor microenvironment. In this review, we describe the development and targeting of OVs, the role of angiogenesis in cancer, and the progress made in arming viruses with antiangiogenic transgenes. Future developments required to optimize this approach are addressed.Keywords: oncolytic virotherapy, cancer

  2. Systemic CD8+ T cell-mediated tumoricidal effects by intratumoral treatment of oncolytic herpes simplex virus with the agonistic monoclonal antibody for murine glucocorticoid-induced tumor necrosis factor receptor.

    Directory of Open Access Journals (Sweden)

    Mikiya Ishihara

    Full Text Available Oncolytic virotherapy combined with immunomodulators is a novel noninvasive strategy for cancer treatment. In this study, we examined the tumoricidal effects of oncolytic HF10, a naturally occurring mutant of herpes simplex virus type-1, combined with an agonistic DTA-1 monoclonal antibody specific for the glucocorticoid-induced tumor necrosis factor receptor. Two murine tumor models were used to evaluate the therapeutic efficacies of HF10 virotherapy combined with DTA-1. The kinetics and immunological mechanisms of DTA-1 in HF10 infection were examined using flow cytometry and immunohistochemistry. Intratumoral administration of HF10 in combination with DTA-1 at a low dose resulted in a more vigorous attenuation of growth of the untreated contralateral as well as the treated tumors than treatment with either HF10 or DTA-1 alone. An accumulation of CD8(+ T cells, including tumor- and herpes simplex virus type-1-specific populations, and a decrease in the number of CD4(+ Foxp3(+ T regulatory cells were seen in both HF10- and DTA-1-treated tumors. Studies using Fc-digested DTA-1 and Fcγ receptor knockout mice demonstrated the direct participation of DTA-1 in regulatory T cell depletion by antibody-dependent cellular cytotoxicity primarily via macrophages. These results indicated the potential therapeutic efficacy of a glucocorticoid-induced tumor necrosis factor receptor-specific monoclonal antibody in oncolytic virotherapy at local tumor sites.

  3. Potent systemic therapy of Multiple Myeloma utilizing Oncolytic Vesicular stomatitis virus coding for Interferon-beta

    OpenAIRE

    Naik, Shruthi; Nace, Rebecca; Barber, Glen N.; Russell, Stephen J.

    2012-01-01

    Multiple myeloma (MM) is an incurable malignancy of plasma secreting B-cells disseminated in the bone marrow. Successful utilization of oncolytic virotherapy for myeloma treatment requires a systemically administered virus that selectively destroys disseminated myeloma cells in an immune-competent host. Vesicular stomatitis virus (VSV) expressing Interferon-β (IFNβ) is a promising new oncolytic agent that exploits tumor-associated defects in innate immune signaling pathways to specifically de...

  4. 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.

  5. 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.

  6. Immunotherapeutic effects of cytokine-induced killer cells combined with CCL21/IL15 armed oncolytic adenovirus in TERT-positive tumor cells.

    Science.gov (United States)

    Ye, Jun-Feng; Lin, Yuan-Qiang; Yu, Xiu-Hua; Liu, Ming-Yuan; Li, Yang

    2016-09-01

    The effective antitumor immune responses are dependent on coordinate interaction of various effector cells. Thus, the combination of adoptive immunotherapy and target gene therapy is capable of efficiently generating a productive antitumor immune response. We investigated whether combination of cytokine-induced killer (CIK) cells adoptive immunotherapy and CCL21/IL15 armed oncolytic adenovirus could induce the enhanced antitumor activity. The CCL21/IL15 co-expression oncolytic adenoviruses were constructed by using the AdEasy system, which uses homologous recombination with shuttle plasmids and full length Ad backbones. This conditionally replicating adenoviruses CRAd-CCL21-IL15 could induce apoptosis in TERTp-positive tumor cells for viral propagation, but do not replicate efficiently in normal cells, because the E1A promoter was replaced by telomerase reverse transcriptase promoter (TERTp). Our results showed that the combination of CIK cells and CRAd-CCL21-IL15 could induce higher antitumor activity than either CIK cells or CRAd-CCL21-IL15 alone. This combined treatment could induce the tumor specific cytotoxicity of CTLs (cytotoxic T lymphocytes) in vitro. Moreover, the treatment of established tumors with the combined therapy of CIK cells and CRAd-CCL21-IL15 resulted in tumor regression. This study suggests that the combined treatment by adoptive immunotherapy and gene therapy is a promising strategy for the therapy of tumor. PMID:27380620

  7. 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...

  8. Anti-tumour activity of oncolytic Western Reserve vaccinia viruses in canine tumour cell lines, xenografts, and fresh tumour biopsies.

    Science.gov (United States)

    Autio, K; Knuuttila, A; Kipar, A; Ahonen, M; Parviainen, S; Diaconu, I; Kanerva, A; Hakonen, T; Vähä-Koskela, M; Hemminki, A

    2014-10-10

    Cancer is one of the most common reasons for death in dogs. One promising approach is oncolytic virotherapy. We assessed the oncolytic effect of genetically modified vaccinia viruses in canine cancer cells, in freshly excised tumour biopsies, and in mice harbouring canine tumour xenografts. Tumour transduction efficacy was assessed using virus expressing luciferase or fluorescent marker genes and oncolysis was quantified by a colorimetric cell viability assay. Oncolytic efficacy in vivo was evaluated in a nude mouse xenograft model. Vaccinia virus was shown to infect most tested canine cancer cell lines and primary surgical tumour tissues. Virus infection significantly reduced tumour growth in the xenograft model. Oncolytic vaccinia virus has antitumour effects against canine cancer cells and experimental tumours and is able to replicate in freshly excised patient tumour tissue. Our results suggest that oncolytic vaccinia virus may offer an effective treatment option for otherwise incurable canine tumours. PMID:25302859

  9. Induction of Interferon Pathways Mediates In Vivo Resistance to Oncolytic Adenovirus

    Science.gov (United States)

    Liikanen, Ilkka; Monsurrò, Vladia; Ahtiainen, Laura; Raki, Mari; Hakkarainen, Tanja; Diaconu, Iulia; Escutenaire, Sophie; Hemminki, Otto; Dias, João D; Cerullo, Vincenzo; Kanerva, Anna; Pesonen, Sari; Marzioni, Daniela; Colombatti, Marco; Hemminki, Akseli

    2011-01-01

    Oncolytic adenoviruses are an emerging experimental approach for treatment of tumors refractory to available modalities. Although preclinical results have been promising, and clinical safety has been excellent, it is also apparent that tumors can become virus resistant. The resistance mechanisms acquired by advanced tumors against conventional therapies are increasingly well understood, which has allowed development of countermeasures. To study this in the context of oncolytic adenovirus, we developed two in vivo models of acquired resistance, where initially sensitive tumors eventually gain resistance and relapse. These models were used to investigate the phenomenon on RNA and protein levels using two types of analysis of microarray data, quantitative reverse transcriptase-polymerase chain reaction and immunohistochemistry. Interferon (IFN) signaling pathways were found upregulated and Myxovirus resistance protein A (MxA) expression was identified as a marker correlating with resistance, while transplantation experiments suggested a role for tumor stroma in maintaining resistance. Furthermore, pathway analysis suggested potential therapeutic targets in oncolytic adenovirus-resistant cells. Improved understanding of the antiviral phenotype causing tumor recurrence is of key importance in order to improve treatment of advanced tumors with oncolytic adenoviruses. Given the similarities between mechanisms of action, this finding might be relevant for other oncolytic viruses as well. PMID:21792178

  10. Mechanistic insights into the oncolytic activity of vesicular stomatitis virus in cancer immunotherapy

    Directory of Open Access Journals (Sweden)

    Simovic B

    2015-10-01

    Full Text Available Boris Simovic, Scott R Walsh, Yonghong Wan Department of Pathology and Molecular Medicine, McMaster Immunology Research Centre, Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada Abstract: Immunotherapy and oncolytic virotherapy have both shown anticancer efficacy in the clinic as monotherapies but the greatest promise lies in therapies that combine these approaches. Vesicular stomatitis virus is a prominent oncolytic virus with several features that promise synergy between oncolytic virotherapy and immunotherapy. This review will address the cytotoxicity of vesicular stomatitis virus in transformed cells and what this means for antitumor immunity and the virus' immunogenicity, as well as how it facilitates the breaking of tolerance within the tumor, and finally, we will outline how these features can be incorporated into the rational design of new treatment strategies in combination with immunotherapy. Keywords: virotherapy, rhabdovirus, anti-tumor immunity, t cell, natural killer cell, therapeutic vaccine

  11. Mitophagy switches cell death from apoptosis to necrosis in NSCLC cells treated with oncolytic measles virus.

    Science.gov (United States)

    Xia, Mao; Meng, Gang; Jiang, Aiqin; Chen, Aiping; Dahlhaus, Meike; Gonzalez, Patrick; Beltinger, Christian; Wei, Jiwu

    2014-06-15

    Although apoptotic phenomena have been observed in malignant cells infected by measles virus vaccine strain Edmonston B (MV-Edm), the precise oncolytic mechanisms are poorly defined. In this study we found that MV-Edm induced autophagy and sequestosome 1-mediated mitophagy leading to decreased cytochrome c release, which blocked the pro-apoptotic cascade in non-small cell lung cancer cells (NSCLCs). The decrease of apoptosis by mitophagy favored viral replication. Persistent viral replication sustained by autophagy ultimately resulted in necrotic cell death due to ATP depletion. Importantly, when autophagy was impaired in NSCLCs MV-Edm-induced cell death was significantly abrogated despite of increased apoptosis. Taken together, our results define a novel oncolytic mechanism by which mitophagy switches cell death from apoptosis to more efficient necrosis in NSCLCs following MV-Edm infection. This provides a foundation for future improvement of oncolytic virotherapy or antiviral therapy. PMID:25004098

  12. 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

  13. Oncolytic adenovirus armed with IL-24 Inhibits the growth of breast cancer in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Zhu Wei

    2012-05-01

    Full Text Available Abstract Background Interleukin-24 (IL-24 is a cytokine that belongs to the IL-10 family. It can selectively induce cancer cell apoptosis which has been utilized as a cancer gene therapy strategy. Methods A recombinant type five adenovirus containing IL-24 gene (designated CNHK600-IL24 was constructed, whose replication is activated only in tumor cells. The replication of CNHK600-IL24 in breast tumor cells and fibroblasts were assessed by TCID50 and MTT assay; the secretion of IL-24 was measured by ELISA and western blotting. The in vivo anti-tumor effect of CNHK600-IL24 was investigated in nude mice carrying orthotopic or metastatic breast tumor. Results We observed that CNHK600-IL24 could replicate efficiently and resulted in high level IL-24 expression and massive cell death in human breast cancer cell MDA-MB-231 but not in normal fibroblast cell MRC-5. In addition, orthotopic breast tumor growth in the nude mice model was significantly suppressed when CNHK600-IL24 was administered. In the metastatic model generated by tail vein injection, CNHK600-IL24 virotherapy significantly improved survival compared with the same virus expressing EGFP (median survival CNHK600-IL24, 55 days vs. CNHK600-EGFP, 41 day, p  Conclusion The oncolytic adenovirus armed with IL-24, which exhibited enhanced anti-tumor activity and improved survival, is a promising candidate for virotherapy of breast cancer.

  14. Moving oncolytic viruses into the clinic: clinical-grade production, purification, and characterization of diverse oncolytic viruses

    Science.gov (United States)

    Ungerechts, Guy; Bossow, Sascha; Leuchs, Barbara; Holm, Per S; Rommelaere, Jean; Coffey, Matt; Coffin, Rob; Bell, John; Nettelbeck, Dirk M

    2016-01-01

    Oncolytic viruses (OVs) are unique anticancer agents based on their pleotropic modes of action, which include, besides viral tumor cell lysis, activation of antitumor immunity. A panel of diverse viruses, often genetically engineered, has advanced to clinical investigation, including phase 3 studies. This diversity of virotherapeutics not only offers interesting opportunities for the implementation of different therapeutic regimens but also poses challenges for clinical translation. Thus, manufacturing processes and regulatory approval paths need to be established for each OV individually. This review provides an overview of clinical-grade manufacturing procedures for OVs using six virus families as examples, and key challenges are discussed individually. For example, different virus features with respect to particle size, presence/absence of an envelope, and host species imply specific requirements for measures to ensure sterility, for handling, and for determination of appropriate animal models for toxicity testing, respectively. On the other hand, optimization of serum-free culture conditions, increasing virus yields, development of scalable purification strategies, and formulations guaranteeing long-term stability are challenges common to several if not all OVs. In light of the recent marketing approval of the first OV in the Western world, strategies for further upscaling OV manufacturing and optimizing product characterization will receive increasing attention. PMID:27088104

  15. Moving oncolytic viruses into the clinic: clinical-grade production, purification, and characterization of diverse oncolytic viruses.

    Science.gov (United States)

    Ungerechts, Guy; Bossow, Sascha; Leuchs, Barbara; Holm, Per S; Rommelaere, Jean; Coffey, Matt; Coffin, Rob; Bell, John; Nettelbeck, Dirk M

    2016-01-01

    Oncolytic viruses (OVs) are unique anticancer agents based on their pleotropic modes of action, which include, besides viral tumor cell lysis, activation of antitumor immunity. A panel of diverse viruses, often genetically engineered, has advanced to clinical investigation, including phase 3 studies. This diversity of virotherapeutics not only offers interesting opportunities for the implementation of different therapeutic regimens but also poses challenges for clinical translation. Thus, manufacturing processes and regulatory approval paths need to be established for each OV individually. This review provides an overview of clinical-grade manufacturing procedures for OVs using six virus families as examples, and key challenges are discussed individually. For example, different virus features with respect to particle size, presence/absence of an envelope, and host species imply specific requirements for measures to ensure sterility, for handling, and for determination of appropriate animal models for toxicity testing, respectively. On the other hand, optimization of serum-free culture conditions, increasing virus yields, development of scalable purification strategies, and formulations guaranteeing long-term stability are challenges common to several if not all OVs. In light of the recent marketing approval of the first OV in the Western world, strategies for further upscaling OV manufacturing and optimizing product characterization will receive increasing attention. PMID:27088104

  16. 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 < 0.001), granulocyte macrophage colony-stimulating factor (GM-CSF) signaling (P < 0.001), and leukocyte extravasation signaling (P < 0.001), in patients surviving a shorter time than their controls. In immunohistochemical analysis, markers CD4 and CD163 were significantly elevated (P = 0.020 and P = 0.016 respectively), in patients with shorter than expected survival. Interestingly, T-cell exhaustion marker TIM-3 was also found to be significantly upregulated (P = 0.006) in patients with poor prognosis. Collectively, these data suggest that activation of several functions of the innate 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. PMID:26310629

  17. Chemovirotherapy of malignant melanoma with a targeted and armed oncolytic measles virus.

    Science.gov (United States)

    Kaufmann, Johanna K; Bossow, Sascha; Grossardt, Christian; Sawall, Stefanie; Kupsch, Jörg; Erbs, Philippe; Hassel, Jessica C; von Kalle, Christof; Enk, Alexander H; Nettelbeck, Dirk M; Ungerechts, Guy

    2013-04-01

    Effective treatment modalities for advanced melanoma are desperately needed. An innovative approach is virotherapy, in which viruses are engineered to infect cancer cells, resulting in tumor cell lysis and an amplification effect by viral replication and spread. Ideally, tumor selectivity of these oncolytic viruses is already determined during viral cell binding and entry, which has not been reported for melanoma. We engineered an oncolytic measles virus entering melanoma cells through the high molecular weight melanoma-associated antigen (HMWMAA) and proved highly specific infection and spread in melanoma cells. We further enhanced this oncolytic virus by inserting the FCU1 gene encoding the yeast-derived prodrug convertases cytosine deaminase and uracil phosphoribosyltransferase. Combination treatment with armed and retargeted MV-FCU1-αHMWMAA and the prodrug 5-fluorocytosine (5-FC) led to effective prodrug conversion to 5-fluorouracil, extensive cytotoxicity to melanoma cells, and excessive bystander killing of noninfected cells. Importantly, HMWMAA-retargeted MV showed antitumor activity in a human xenograft mouse model, which was further increased by the FCU1/5-FC prodrug activation system. Finally, we demonstrated susceptibility of melanoma skin metastasis biopsies to HMWMAA-retargeted MV. The highly selective, entry-targeted and armed oncolytic virus MV-FCU1-αHMWMAA may become a potent building block of future melanoma therapies. PMID:23223133

  18. 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

  19. In vivo magnetic resonance imaging and spectroscopy identifies oncolytic adenovirus responders.

    Science.gov (United States)

    Hemminki, O; Immonen, R; Närväinen, J; Kipar, A; Paasonen, J; Jokivarsi, K T; Yli-Ollila, H; Soininen, P; Partanen, K; Joensuu, T; Parvianen, S; Pesonen, S K; Koski, A; Vähä-Koskela, M; Cerullo, V; Pesonen, S; Gröhn, O H; Hemminki, A

    2014-06-15

    At present, it is not possible to reliably identify patients who will benefit from oncolytic virus treatments. Conventional modalities such as computed tomography (CT), which measure tumor size, are unreliable owing to inflammation-induced tumor swelling. We hypothesized that magnetic resonance imaging (MRI) and spectroscopy (MRS) might be useful in this regard. However, little previous data exist and neither oncolytic adenovirus nor immunocompetent models have been assessed by MRS. Here, we provide evidence that in T2-weighted MRI a hypointense core area, consistent with coagulative necrosis, develops in immunocompetent Syrian hamster carcinomas that respond to oncolytic adenovirus treatment. The same phenomenon was observed in a neuroblastoma patient while he responded to the treatment. With relapse at a later stage, however, the tumor of this patient became moderately hyperintense. We found that MRS of taurine, choline and unsaturated fatty acids can be useful early indicators of response and provide detailed information about tumor growth and degeneration. In hamsters, calprotectin-positive inflammatory cells (heterophils and macrophages) were found in abundance; particularly surrounding necrotic areas in carcinomas and T cells were significantly increased in sarcomas, when these had been treated with a granulocyte-macrophage colony-stimulating factor-producing virus, suggesting a possible link between oncolysis, necrosis (seen as a hypointense core in MRI) and/or immune response. Our study indicates that both MRI and MRS could be useful in the estimation of oncolytic adenovirus efficacy at early time points after treatment. PMID:24248808

  20. 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

  1. Differential dust attenuation in CALIFA galaxies

    Science.gov (United States)

    Vale Asari, N.; Cid Fernandes, R.; Amorim, A. L.; Lacerda, E. A. D.; Schlickmann, M.; Wild, V.; Kennicutt, R. C.

    2016-06-01

    Dust attenuation has long been treated as a simple parameter in SED fitting. Real galaxies are, however, much more complicated: The measured dust attenuation is not a simple function of the dust optical depth, but depends strongly on galaxy inclination and the relative distribution of stars and dust. We study the nebular and stellar dust attenuation in CALIFA galaxies, and propose some empirical recipes to make the dust treatment more realistic in spectral synthesis codes. By adding optical recombination emission lines, we find better constraints for differential attenuation. Those recipes can be applied to unresolved galaxy spectra, and lead to better recovered star formation rates.

  2. Characterization of a full-length infectious cDNA clone and a GFP reporter derivative of the oncolytic picornavirus SVV-001.

    Science.gov (United States)

    Poirier, John T; Reddy, P Seshidhar; Idamakanti, Neeraja; Li, Shawn S; Stump, Kristine L; Burroughs, Kevin D; Hallenbeck, Paul L; Rudin, Charles M

    2012-12-01

    Seneca Valley virus (SVV-001) is an oncolytic picornavirus with selective tropism for a subset of human cancers with neuroendocrine differentiation. To characterize further the specificity of SVV-001 and its patterns and kinetics of intratumoral spread, bacterial plasmids encoding a cDNA clone of the full-length wild-type virus and a derivative virus expressing GFP were generated. The full-length cDNA of the SVV-001 RNA genome was cloned into a bacterial plasmid under the control of the T7 core promoter sequence to create an infectious cDNA clone, pNTX-09. A GFP reporter virus cDNA clone, pNTX-11, was then generated by cloning a fusion protein of GFP and the 2A protein from foot-and-mouth disease virus immediately following the native SVV-001 2A sequence. Recombinant GFP-expressing reporter virus, SVV-GFP, was rescued from cells transfected with in vitro RNA transcripts from pNTX-11 and propagated in cell culture. The proliferation kinetics of SVV-001 and SVV-GFP were indistinguishable. The SVV-GFP reporter virus was used to determine that a subpopulation of permissive cells is present in small-cell lung cancer cell lines previously thought to lack permissivity to SVV-001. Finally, it was shown that SVV-GFP administered to tumour-bearing animals homes in to and infects tumours whilst having no detectable tropism for normal mouse tissues at 1×10(11) viral particles kg(-1), a dose equivalent to that administered in ongoing clinical trials. These infectious clones will be of substantial value in further characterizing the biology of this virus and as a backbone for the generation of additional oncolytic derivatives. PMID:22971818

  3. 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.

  4. Oncolytic Newcastle Disease Virus as Cutting Edge between Tumor and Host

    Directory of Open Access Journals (Sweden)

    Philippe Fournier

    2013-07-01

    Full Text Available Oncolytic viruses (OVs replicate selectively in tumor cells and exert anti-tumor cytotoxic activity. Among them, Newcastle Disease Virus (NDV, a bird RNA virus of the paramyxovirus family, appears outstanding. Its anti-tumor effect is based on: (i oncolytic activity and (ii immunostimulation. Together these activities facilitate the induction of post-oncolytic adaptive immunity. We will present milestones during the last 60 years of clinical evaluation of this virus. Two main strategies of clinical application were followed using the virus (i as a virotherapeutic agent, which is applied systemically or (ii as an immunostimulatory agent combined with tumor cells for vaccination of cancer patients. More recently, a third strategy evolved. It combines the strategies (i and (ii and includes also dendritic cells (DCs. The first step involves systemic application of NDV to condition the patient. The second step involves intradermal application of a special DC vaccine pulsed with viral oncolysate. This strategy, called NDV/DC, combines anti-cancer activity (oncolytic virotherapy and immune-stimulatory properties (oncolytic immunotherapy with the high potential of DCs (DC therapy to prime naive T cells. The aim of such treatment is to first prepare the cancer-bearing host for immunocompetence and then to instruct the patient’s immune system with information about tumor-associated antigens (TAAs of its own tumor together with danger signals derived from virus infection. This multimodal concept should optimize the generation of strong polyclonal T cell reactivity targeted against the patient’s TAAs and lead to the establishment of a long-lasting memory T cell repertoire.

  5. Treatment of medulloblastoma with oncolytic measles viruses expressing the angiogenesis inhibitors endostatin and angiostatin

    International Nuclear Information System (INIS)

    Medulloblastoma is the most common type of pediatric brain tumor. Although numerous factors influence patient survival rates, more than 30% of all cases will ultimately be refractory to conventional therapies. Current standards of care are also associated with significant morbidities, giving impetus for the development of new treatments. We have previously shown that oncolytic measles virotherapy is effective against medulloblastoma, leading to significant prolongation of survival and even cures in mouse xenograft models of localized and metastatic disease. Because medulloblastomas are known to be highly vascularized tumors, we reasoned that the addition of angiogenesis inhibitors could further enhance the efficacy of oncolytic measles virotherapy. Toward this end, we have engineered an oncolytic measles virus that express a fusion protein of endostatin and angiostatin, two endogenous and potent inhibitors of angiogenesis. Oncolytic measles viruses encoding human and mouse variants of a secretable endostatin/angiostatin fusion protein were designed and rescued according to established protocols. These viruses, known as MV-hE:A and MV-mE:A respectively, were then evaluated for their anti-angiogenic potential and efficacy against medulloblastoma cell lines and orthotopic mouse models of localized disease. Medulloblastoma cells infected by MV-E:A readily secrete endostatin and angiostatin prior to lysis. The inclusion of the endostatin/angiostatin gene did not negatively impact the measles virus’ cytotoxicity against medulloblastoma cells or alter its growth kinetics. Conditioned media obtained from these infected cells was capable of inhibiting multiple angiogenic factors in vitro, significantly reducing endothelial cell tube formation, viability and migration compared to conditioned media derived from cells infected by a control measles virus. Mice that were given a single intratumoral injection of MV-E:A likewise showed reduced numbers of tumor-associated blood

  6. Development of a model based on oncolytic adenovirus loaded with L-carnosine as a drug delivery system for cancer therapy

    OpenAIRE

    Garofalo, Mariangela

    2015-01-01

    Oncolytic viruses are viruses that are able to replicate specifically and infect and destroy only tumor cells. Many clinical studies have shown that the oncolytic approach alone could not efficiently destroy the large tumor mass, thus by limiting an efficacy virotherapy. Combination of oncolytic adenoviruses (Ads) and chemotherapeutic drugs has shown promising therapeutic results due to the synergistic action of virus and drug and is considered as a potential approach for cancer therapy. In t...

  7. Arming viruses in multi-mechanistic oncolytic viral therapy: current research and future developments, with emphasis on poxviruses

    OpenAIRE

    Thorne, Steve

    2013-01-01

    Padma Sampath, Steve H ThorneDepartment of Surgery, University of Pittsburgh Cancer Institute, University of Pittsburgh, Pittsburgh, PA, USAAbstract: The field of oncolytic virology has made great strides in recent years. However, one key finding has been that the use of viral agents that replicate selectively in tumors is usually insufficient to achieve anything beyond small and transient responses. Instead, like most cancer therapies, oncolytic viruses are most effective in combination with...

  8. A pRb-responsive, RGD-modified, and Hyaluronidase-armed Canine Oncolytic Adenovirus for Application in Veterinary Oncology

    OpenAIRE

    Laborda, Eduardo; Puig-Saus, Cristina; Rodriguez-García, Alba; Moreno, Rafael; Cascalló, Manel; Pastor, Josep; Alemany, Ramon

    2014-01-01

    Human and canine cancer share similarities such as genetic and molecular aspects, biological complexity, tumor epidemiology, and targeted therapeutic treatment. Lack of good animal models for human adenovirotherapy has spurred the use of canine adenovirus 2-based oncolytic viruses. We have constructed a canine oncolytic virus that mimics the characteristics of our previously published human adenovirus ICOVIR17: expression of E1a controlled by E2F sites, deletion of the pRb-binding site of E1a...

  9. Identification and characterization of alphavirus M1 as a selective oncolytic virus targeting ZAP-defective human cancers

    OpenAIRE

    Lin, Yuan; Zhang, Haipeng; Liang, Jiankai; Kai LI; Zhu, Wenbo; FU, LIWU; Wang, Fang; Zheng, Xiaoke; Shi, Huijuan; Wu, Sihan; Xiao, Xiao; Chen, Lijun; TANG, LIPENG; Yan, Min; Yang, Xiaoxiao

    2014-01-01

    Although oncolytic virotherapy is showing great promise in clinical trials, not all patients are benefiting. Identifying predictors of therapeutic effectiveness for each oncolytic virus would provide a good chance to increase response rate. Here, we describe an alphavirus (M1) that possesses selective and potent antitumor activity through intravenous infusion, whereas its replication is controlled by the zinc-finger antiviral protein (ZAP) gene. A survey of cancer tissue banks reveals that ZA...

  10. An Oncolytic Adenovirus Expressing Herpes Simplex Virus-Thymidine Kinase for Targeting Cancer Therapy: An in vitro Evaluation

    Institute of Scientific and Technical Information of China (English)

    Fei-qun Zheng; Yin Xu; Yi-de Qin; Ren-jie Yang; Jun Han

    2009-01-01

    Objective: Oncolytic adenovirus, also called conditionally replicating adenovirus (CRAD), has been developed for the treatment of cancer. However, there is a tremendous need to enhance their antitumor efficacy. Here we wish to evaluate whether a strategy that combines the herpes simplex virus-thymidine kinase with oncolytic effects offers a therapeutic advantage.Methods: A novel adenovirus Ad-ETK containing a sequentially positioned promoter of human telomerase reverse transcriptase (hTERT), the coding sequence of E1A gene, an internal ribosome entry site sequence (IRES) and the coding sequence of herpes simplex virus-thymidine kinase (HSV-TK) was constructed. Infection of various cells with Ad-ETK followed by RT-PCR confirmed the expression of E1A and HSV-TK. The oncolytic ability and synergism between oncolytic effects and HSV-TK system was measured. The infection efficiency was determined by flow cytometry.Results: Ad-ETK deliverys E1A and HSV-TK gene, which selectively replicates in hTERT-positive tumor cells, and the progeny virus can reach up to 150 IU/cell. Our in vitro study showed that Ad-ETK plus ganciclovir (GCV) induced an obvious cell death.Conclusion: An oncolytic adenovirus plus the HSV-TK/GCV suicide gene system resulted in a significant improvement in treatment efficacy and it may offer important considerations in the development and preclinical assessments of oncolytic virotherapy.

  11. Ad 2.0: a novel recombineering platform for high-throughput generation of tailored adenoviruses.

    Science.gov (United States)

    Mück-Häusl, Martin; Solanki, Manish; Zhang, Wenli; Ruzsics, Zsolt; Ehrhardt, Anja

    2015-04-30

    Recombinant adenoviruses containing a double-stranded DNA genome of 26-45 kb were broadly explored in basic virology, for vaccination purposes, for treatment of tumors based on oncolytic virotherapy, or simply as a tool for efficient gene transfer. However, the majority of recombinant adenoviral vectors (AdVs) is based on a small fraction of adenovirus types and their genetic modification. Recombineering techniques provide powerful tools for arbitrary engineering of recombinant DNA. Here, we adopted a seamless recombineering technology for high-throughput and arbitrary genetic engineering of recombinant adenoviral DNA molecules. Our cloning platform which also includes a novel recombination pipeline is based on bacterial artificial chromosomes (BACs). It enables generation of novel recombinant adenoviruses from different sources and switching between commonly used early generation AdVs and the last generation high-capacity AdVs lacking all viral coding sequences making them attractive candidates for clinical use. In combination with a novel recombination pipeline allowing cloning of AdVs containing large and complex transgenes and the possibility to generate arbitrary chimeric capsid-modified adenoviruses, these techniques allow generation of tailored AdVs with distinct features. Our technologies will pave the way toward broader applications of AdVs in molecular medicine including gene therapy and vaccination studies. PMID:25609697

  12. Triple-controlled oncolytic adenovirus expressing melittin to exert inhibitory efficacy on hepatocellular carcinoma

    OpenAIRE

    Qian, Chun-Yu; Wang, Kai-Li; Fang, Fan-Fu; Gu, Wei; Huang, Feng; Wang, Fu-Zhe; Li, Bai; Wang, Li-Na

    2015-01-01

    Hepatocellular carcinoma (HCC) is a highly malignant disease, and its outcome of routine therapies is poor. Comprehensive treatment including gene therapy is an important way to improve patients’ prognosis and survival. In this study, we successfully constructed a triple-controlled cancer-selective oncolytic adenovirus, QG511-HA-Melittin, carrying melittin gene, in which the hybrid promoter, hypoxia-response element (HRE)-AFP promoter, was used to control viral E1a expression targeting AFP-po...

  13. pH-sensitive oncolytic adenovirus hybrid targeting acidic tumor microenvironment and angiogenesis

    OpenAIRE

    Choi, Joung-Woo; Jung, Soo-Jung; Kasala, Dayananda; Hwang, June Kyu; Hu, Jun; Bae, You Han; Yun, Chae-Ok

    2015-01-01

    Although oncolytic adenoviruses (Ads) are an attractive option for cancer gene therapy, the intravenous administration of naked Ad still encounters unfavorable host responses, non-specific interactions, and heterogeneity in targeted cancer cells. To overcome these obstacles and achieve specific targeting of the tumor microenvironment, Ad was coated with the pH-sensitive block copolymer, methoxy poly(ethylene glycol)-b-poly(l-histidine-co-l-phenylalanine) (PEGbPHF). The physicochemical propert...

  14. Oncolytic Semliki forest virus vector as a novel candidate against unresectable osteosarcoma.

    Science.gov (United States)

    Ketola, Anna; Hinkkanen, Ari; Yongabi, Felicitas; Furu, Petra; Määttä, Ann-Marie; Liimatainen, Timo; Pirinen, Risto; Björn, Marko; Hakkarainen, Tanja; Mäkinen, Kimmo; Wahlfors, Jarmo; Pellinen, Riikka

    2008-10-15

    Oncolytic viruses are a promising tool for treatment of cancer. We studied an oncolytic Semliki Forest virus (SFV) vector, VA7, carrying the enhanced green fluorescent protein gene (EGFP), as a novel virotherapy candidate against unresectable osteosarcoma. The efficiency and characteristics of the VA7-EGFP treatment were compared with a widely studied oncolytic adenovirus, Ad5Delta24, both in vitro and in vivo. VA7-EGFP resulted in more rapid oncolysis and was more efficient at low multiplicities of infection (MOI) when compared with Ad5Delta24 in vitro. Yet, in MG-63 cells, a subpopulation resistant to the VA7-EGFP vector emerged. In subcutaneous human osteosarcoma xenografts in nude mice treatment with either vector reduced tumor size, whereas tumors in control mice expanded quickly. The VA7-EGFP-treated tumors were either completely abolished or regressed to pinpoint size. The efficacy of VA7-EGFP vector was studied also in an orthotopic osteosarcoma nude mouse model characterized by highly aggressive tumor growth. Treatment with oncolytic SFV extended survival of the animals significantly (P < 0.01), yet none of the animals were finally cured. Sera from SFV-treated mice contained neutralizing antibodies, and as nude mice are not able to establish IgG response, the result points out the role of IgM class antibodies in clearance of virus from peripheral tumors. Furthermore, biodistribution analysis at the survival end point verified the presence of virus in some of the brain samples, which is in line with previous studies demonstrating that IgG is required for clearance of SFV from central nervous system. PMID:18922906

  15. A novel oncolytic herpes simplex virus type 2 has potent anti-tumor activity.

    Directory of Open Access Journals (Sweden)

    Qian Zhao

    Full Text Available Oncolytic viruses are promising treatments for many kinds of solid tumors. In this study, we constructed a novel oncolytic herpes simplex virus type 2: oHSV2. We investigated the cytopathic effects of oHSV2 in vitro and tested its antitumor efficacy in a 4T1 breast cancer model. We compared its effect on the cell cycle and its immunologic impact with the traditional chemotherapeutic agent doxorubicin. In vitro data showed that oHSV2 infected most of the human and murine tumor cell lines and was highly oncolytic. oHSV2 infected and killed 4T1 tumor cells independent of their cell cycle phase, whereas doxorubicin mainly blocked cells that were in S and G2/M phase. In vivo study showed that both oHSV2 and doxorubicin had an antitumor effect, though the former was less toxic. oHSV2 treatment alone not only slowed down the growth of tumors without causing weight loss but also induced an elevation of NK cells and mild decrease of Tregs in spleen. In addition, combination therapy of doxorubicin followed by oHSV2 increased survival with weight loss than oHSV2 alone. The data showed that the oncolytic activity of oHSV2 was similar to oHSV1 in cell lines examined and in vivo. Therefore, we concluded that our virus is a safe and effective therapeutic agent for 4T1 breast cancer and that the sequential use of doxorubicin followed by oHSV2 could improve antitumor activity without enhancing doxorubicin's toxicity.

  16. Progress in clinical oncolytic virus-based therapy for hepatocellular carcinoma

    OpenAIRE

    Jebar, AH; Errington-Mais, F; Vile, RG; Selby, PJ; Melcher, AA; S. Griffin(Physics Department, McGill University, Montreal, QC H3A 2T8, Canada)

    2015-01-01

    Hepatocellular carcinoma (HCC) carries a dismal prognosis, with advanced disease being resistant to both radiotherapy and conventional cytotoxic drugs, whilst anti-angiogenic drugs are marginally efficacious. Oncolytic viruses (OVs) offer the promise of selective cancer therapy through direct and immune-mediated mechanisms. The premise of OVs lies in their preferential genomic replication, protein expression and productive infection of malignant cells. Numerous OVs are being tested in preclin...

  17. 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.

  18. T-cell Subsets in Peripheral Blood and Tumors of Patients Treated With Oncolytic Adenoviruses

    Science.gov (United States)

    Kristian, Taipale; Ilkka, Liikanen; Juuso, Juhila; Aila, Karioja-Kallio; Minna, Oksanen; Riku, Turkki; Nina, Linder; Johan, Lundin; Ari, Ristimäki; Anna, Kanerva; Anniina, Koski; Timo, Joensuu; Markus, Vähä-Koskela; Akseli, Hemminki

    2015-01-01

    The quality of the antitumor immune response is decisive when developing new immunotherapies for cancer. Oncolytic adenoviruses cause a potent immunogenic stimulus and arming them with costimulatory molecules reshapes the immune response further. We evaluated peripheral blood T-cell subsets of 50 patients with refractory solid tumors undergoing treatment with oncolytic adenovirus. These data were compared to changes in antiviral and antitumor T cells, treatment efficacy, overall survival, and T-cell subsets in pre- and post-treatment tumor biopsies. Treatment caused a significant (P < 0.0001) shift in T-cell subsets in blood, characterized by a proportional increase of CD8+ cells, and decrease of CD4+ cells. Concomitant treatment with cyclophosphamide and temozolomide resulted in less CD4+ decrease (P = 0.041) than cyclophosphamide only. Interestingly, we saw a correlation between T-cell changes in peripheral blood and the tumor site. This correlation was positive for CD8+ and inverse for CD4+ cells. These findings give insight to the interconnections between peripheral blood and tumor-infiltrating lymphocyte (TIL) populations regarding oncolytic virotherapy. In particular, our data suggest that induction of T-cell response is not sufficient for clinical response in the context of immunosuppressive tumors, and that peripheral blood T cells have a complicated and potentially misleading relationship with TILs. PMID:25655312

  19. 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.

  20. Development of an Oncolytic Adenovirus with Enhanced Spread Ability through Repeated UV Irradiation and Cancer Selection.

    Science.gov (United States)

    Wechman, Stephen L; Rao, Xiao-Mei; Cheng, Pei-Hsin; Gomez-Gutierrez, Jorge G; McMasters, Kelly M; Zhou, H Sam

    2016-01-01

    Oncolytic adenoviruses (Ads) have been shown to be safe and have great potential for the treatment of solid tumors. However, the therapeutic efficacy of Ads is antagonized by limited spread within solid tumors. To develop Ads with enhanced spread, viral particles of an E1-wildtype Ad5 dl309 was repeatedly treated with UV type C irradiation and selected for the efficient replication and release from cancer cells. After 72 cycles of treatment and cancer selection, AdUV was isolated. This vector has displayed many favorable characteristics for oncolytic therapy. AdUV was shown to lyse cancer cells more effectively than both E1-deleted and E1-wildtype Ads. This enhanced cancer cell lysis appeared to be related to increased AdUV replication in and release from infected cancer cells. AdUV-treated A549 cells displayed greater expression of the autophagy marker LC3-II during oncolysis and formed larger viral plaques upon cancer cell monolayers, indicating increased virus spread among cancer cells. This study indicates the potential of this approach of irradiation of entire viral particles for the development of oncolytic viruses with designated therapeutic properties. PMID:27314377

  1. Development of an Oncolytic Adenovirus with Enhanced Spread Ability through Repeated UV Irradiation and Cancer Selection

    Directory of Open Access Journals (Sweden)

    Stephen L. Wechman

    2016-06-01

    Full Text Available Oncolytic adenoviruses (Ads have been shown to be safe and have great potential for the treatment of solid tumors. However, the therapeutic efficacy of Ads is antagonized by limited spread within solid tumors. To develop Ads with enhanced spread, viral particles of an E1-wildtype Ad5 dl309 was repeatedly treated with UV type C irradiation and selected for the efficient replication and release from cancer cells. After 72 cycles of treatment and cancer selection, AdUV was isolated. This vector has displayed many favorable characteristics for oncolytic therapy. AdUV was shown to lyse cancer cells more effectively than both E1-deleted and E1-wildtype Ads. This enhanced cancer cell lysis appeared to be related to increased AdUV replication in and release from infected cancer cells. AdUV-treated A549 cells displayed greater expression of the autophagy marker LC3-II during oncolysis and formed larger viral plaques upon cancer cell monolayers, indicating increased virus spread among cancer cells. This study indicates the potential of this approach of irradiation of entire viral particles for the development of oncolytic viruses with designated therapeutic properties.

  2. Immunogenic cell death by oncolytic herpes simplex virus type 1 in squamous cell carcinoma cells.

    Science.gov (United States)

    Takasu, A; Masui, A; Hamada, M; Imai, T; Iwai, S; Yura, Y

    2016-04-01

    Molecules essential for the induction of immunogenic cell death (ICD) are called damage-associated molecular patterns (DAMPs). The effects of oncolytic herpes simplex virus type 1 (HSV-1) on the production of DAMPs were examined in squamous cell carcinoma (SCC) cells. The cytopathic effects of HSV-1 RH2 were observed in mouse SCCVII cells infected at a high multiplicity of infection (MOI), and the amounts of viable cells were decreased. After being infected with RH2, ATP and high mobility group box 1 (HMGB1) were released extracellulary, while calreticulin (CRT) translocated to the cell membrane. A flow-cytometric analysis revealed an increase in the number of annexin-V and propidium iodide (PI)-stained cells; and the amount of cleaved poly (ADP-ribose) polymerase (PARP) was increased. The killing effect of RH2 was reduced by pan-caspase inhibitor z-VAD-fmk and the caspase-1 inhibitor z-YVAD-fmk, suggesting the involvement of apoptosis and pyroptosis. In C3H mice bearing synergic SCCVII tumors, the growth of tumors injected with the supernatant of RH2-infected cells was less than that of tumors injected with phosphate-buffered saline (PBS). These results indicate that oncolytic HSV-1 RH2 produces DAMPs from SCC cells to induce cell death. This may contribute to the enhancement of tumor immunity by oncolytic HSV-1. PMID:26987291

  3. The integrin inhibitor cilengitide enhances the anti-glioma efficacy of vasculostatin-expressing oncolytic virus

    Science.gov (United States)

    Fujii, Kentaro; Kurozumi, Kazuhiko; Ichikawa, Tomotsugu; Onishi, Manabu; Shimazu, Yosuke; Ishida, Joji; Chiocca, E. Antonio; Kaur, Balveen; Date, Isao

    2016-01-01

    Oncolytic viral (OV) therapy has been considered as a promising treatment modality for brain tumors. Vasculostatin, the fragment of brain-specific angiogenesis inhibitor-1, shows anti-angiogenic activity against malignant gliomas. Previously, a vasculostatin-expressing oncolytic HSV-1, Rapid Antiangiogenesis Mediated By Oncolytic virus (RAMBO), was reported to have a potent antitumor effect. Here, we investigated the therapeutic efficacy of RAMBO and cilengitide, an integrin inhibitor, combination therapy for malignant glioma. In vitro, tube formation was significantly decreased in RAMBO and cilengitide combination treatment compared to RAMBO or cilengitide monotherapy. Moreover, combination treatment induced a synergistic suppressive effect on endothelial cell migration compared to the control virus. RAMBO, combined with cilengitide, induced synergistic cytotoxicity on glioma cells. In the caspase-8 and -9 assays, the relative absorption of U87ΔEGFR cell clusters treated with cilengitide and with RAMBO was significantly higher than of those treated with control. In addition, the activity of caspase 3/7 was significantly increased with combination therapy. In vivo, there was a significant increase in the survival of mice treated with combination therapy compared to RAMBO or cilengitide monotherapy. These results indicate that cilengitide enhanced vasculostatin-expressing OV therapy for malignant glioma and provide a rationale for designing future clinical trials combining these two agents. PMID:23827879

  4. Transient fasting enhances replication of oncolytic herpes simplex virus in glioblastoma

    Science.gov (United States)

    Esaki, Shinichi; Rabkin, Samuel D; Martuza, Robert L; Wakimoto, Hiroaki

    2016-01-01

    Short-term nutritional restriction (fasting) has been shown to enhance the efficacy of chemotherapy by sensitizing cancer cells and protecting normal cells in a variety of cancer models, including glioblastoma (GBM). Cancer cells, unlike normal cells, respond to fasting by promoting oncogenic signaling and protein synthesis. We hypothesized that fasting would increase the replication of oncolytic herpes simplex virus (oHSV) in GBM. Patient-derived GBM cell lines were fasted by growth in glucose and fetal calf serum restricted culture medium. “Transient fasting”, 24-hour fasting followed by 24-hour recovery in complete medium, increased late virus gene expression and G47Δ yields about 2-fold in GBM cells, but not in human astrocytes, and enhanced G47Δ killing of GBM cells. Mechanistically, “transient fasting” suppressed phosphorylation of the subunit of eukaryotic initiation factor 2α (eIF2α) and c-Jun N-terminal kinases (JNK) in GBM cells, but not in astrocytes. Pharmacological inhibition of JNK also increased G47Δ yield. In vivo, transient fasting (48-hour food restriction and 24-hour recovery) doubled luciferase activity after intratumoral G47Δ-US11fluc injection into orthotopic GBM xenografts. Thus, “transient fasting” increases G47Δ replication and oncolytic activity in human GBM cells. These results suggest that “transient fasting” may be effectively combined to enhance oncolytic HSV therapy of GBM. PMID:27186404

  5. Oncolytic Adenovirus Loaded with L-carnosine as Novel Strategy to Enhance the Antitumor Activity.

    Science.gov (United States)

    Garofalo, Mariangela; Iovine, Barbara; Kuryk, Lukasz; Capasso, Cristian; Hirvinen, Mari; Vitale, Andrea; Yliperttula, Marjo; Bevilacqua, Maria Assunta; Cerullo, Vincenzo

    2016-04-01

    Oncolytic viruses are able to specifically replicate, infect, and kill only cancer cells. Their combination with chemotherapeutic drugs has shown promising results due to the synergistic action of virus and drugs; the combinatorial therapy is considered a potential clinically relevant approach for cancer. In this study, we optimized a strategy to absorb peptides on the viral capsid, based on electrostatic interaction, and used this strategy to deliver an active antitumor drug. We used L-carnosine, a naturally occurring histidine dipeptide with a significant antiproliferative activity. An ad hoc modified, positively charged L-carnosine was combined with the capsid of an oncolytic adenovirus to generate an electrostatic virus-carnosine complex. This complex showed enhanced antitumor efficacy in vitro and in vivo in different tumor models. In HCT-116 colorectal and A549 lung cancer cell lines, the complex showed higher transduction ratio and infectious titer compared with an uncoated oncolytic adenovirus. The in vivo efficacy of the complex was tested in lung and colon cancer xenograft models, showing a significant reduction in tumor growth. Importantly, we investigated the molecular mechanisms underlying the effects of complex on tumor growth reduction. We found that complex induces apoptosis in both cell lines, by using two different mechanisms, enhancing viral replication and affecting the expression of Hsp27. Our system could be used in future studies also for delivery of other bioactive drugs. Mol Cancer Ther; 15(4); 651-60. ©2016 AACR. PMID:26861248

  6. 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.

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

    International Nuclear Information System (INIS)

    The primary objective of this study was to test whether oncolytic herpes simplex virus type 1 (HSV1) could eradicate chemoresistant cancer stem cells (CSCs). 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. 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<0.05). Though more CD8+ T lymphocytes were induced by oncolytic HSV1, no significant specific T cell response against CSCs was detected in vivo. These results suggested that the use of oncolytic HSV1 following doxorubicin treatment may help eradicate residual chemoresistant CSCs in vivo

  8. Attenuation of PRRSV by chimera construction

    Science.gov (United States)

    Two genetically distinct infectious recombinant virus clones (pMLV, constructed from Ingelvac® PRRS MLV and pMN184, constructed from virulent strain MN184) were developed to study attenuation of contemporary PRRSV. Two reciprocal chimeric clones (pMLVORF1/MN184 and pMN184ORF1/MLV) were then constru...

  9. Intramuscular Inoculation of Mice with the Live-Attenuated Recombinant Rabies Virus TriGAS Results in a Transient Infection of the Draining Lymph Nodes and a Robust, Long-Lasting Protective Immune Response against Rabies

    OpenAIRE

    Schutsky, Keith; Curtis, Dana; Bongiorno, Emily K.; Barkhouse, Darryll A; Kean, Rhonda B; Dietzschold, Bernhard; Hooper, D. Craig; Faber, Milosz

    2013-01-01

    A single intramuscular application of the live but not UV-inactivated recombinant rabies virus (RABV) variant TriGAS in mice induces the robust and sustained production of RABV-neutralizing antibodies that correlate with long-term protection against challenge with an otherwise lethal dose of the wild-type RABV. To obtain insight into the mechanism by which live TriGAS induces long-lasting protective immunity, quantitative PCR (qPCR) analysis of muscle tissue, draining lymph nodes, spleen, spi...

  10. 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.

  11. 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...

  12. 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.

  13. Therapeutic Use of Native and Recombinant Enteroviruses.

    Science.gov (United States)

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

    2016-03-01

    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. PMID:26907330

  14. 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.

  15. Rotary antenna attenuator

    Science.gov (United States)

    Dickinson, R. M.; Hardy, J. C.

    1969-01-01

    Radio frequency attenuator, having negligible insertion loss at minimum attenuation, can be used for making precise antenna gain measurements. It is small in size compared to a rotary-vane attenuator.

  16. Treatment of breast cancer stem cells with oncolytic herpes simplex virus

    OpenAIRE

    Hu, P; Li, J.; Zeng, W.; Zhang, Q; Rabkin, Samuel David; R. Liu

    2012-01-01

    Cancer stem cells have recently been isolated from several different solid tumors. In breast cancer, the \\(CD44^{+} CD24^{−/low}\\) population is considered to comprise stem-like cells. The identification of cancer stem cells has provided new targets for the development of therapeutics. Oncolytic herpes simplex viruses (oHSVs) are an effective strategy for killing breast cancer cells and treating breast tumors in preclinical models. Here, we examined the efficacy of the oHSV G47Δ in killing br...

  17. Arming viruses in multi-mechanistic oncolytic viral therapy: current research and future developments, with emphasis on poxviruses

    Directory of Open Access Journals (Sweden)

    Sampath P

    2013-12-01

    Full Text Available Padma Sampath, Steve H ThorneDepartment of Surgery, University of Pittsburgh Cancer Institute, University of Pittsburgh, Pittsburgh, PA, USAAbstract: The field of oncolytic virology has made great strides in recent years. However, one key finding has been that the use of viral agents that replicate selectively in tumors is usually insufficient to achieve anything beyond small and transient responses. Instead, like most cancer therapies, oncolytic viruses are most effective in combination with other therapies, which is where they have proven therapeutic effects in clinical and preclinical studies. In cases of some of the smaller RNA viruses, effects can only be achieved through combination regimens with chemotherapy, radiotherapy, or targeted conventional therapies. However, larger DNA viruses are able to express one or more transgenes; thus, therapeutic mechanisms can be built into the viral vector itself. The incorporated approaches into arming oncolytic viruses through transgene expression will be the main focus of this review, including use of immune activators, prodrug converting enzymes, anti-angiogenic factors, and targeting of the stroma. This will focus on poxviruses as model systems with large cloning capacities, which have routinely been used as transgene expression vectors in different settings, including vaccine and oncolytic viral therapy.Keywords: vaccinia, poxvirus, immunotherapy, angiogenesis, prodrug

  18. Biodistribution Analysis of Oncolytic Adenoviruses in Patient Autopsy Samples Reveals Vascular Transduction of Noninjected Tumors and Tissues.

    Science.gov (United States)

    Koski, Anniina; Bramante, Simona; Kipar, Anja; Oksanen, Minna; Juhila, Juuso; Vassilev, Lotta; Joensuu, Timo; Kanerva, Anna; Hemminki, Akseli

    2015-10-01

    In clinical trials with oncolytic adenoviruses, there has been no mortality associated with treatment vectors. Likewise, in the Advanced Therapy Access Program (ATAP), where 290 patients were treated with 10 different viruses, no vector-related mortality was observed. However, as the patient population who received adenovirus treatments in ATAP represented heavily pretreated patients, often with very advanced disease, some patients died relatively soon after receiving their virus treatment mandating autopsy to investigate cause of death. Eleven such autopsies were performed and confirmed disease progression as the cause of death in each case. The regulatory requirement for investigating the safety of advanced therapy medical products presented a unique opportunity to study tissue samples collected as a routine part of the autopsies. Oncolytic adenoviral DNA was recovered in a wide range of tissues, including injected and noninjected tumors and various normal tissues, demonstrating the ability of the vector to disseminate through the vascular route. Furthermore, we recovered and cultured viable virus from samples of noninjected brain metastases of an intravenously treated patient, confirming that oncolytic adenovirus can reach tumors through the intravascular route. Data presented here give mechanistic insight into mode of action and biodistribution of oncolytic adenoviruses in cancer patients. PMID:26156245

  19. Oncolytic immunotherapy through tumor-specific translation and cytotoxicity of poliovirus.

    Science.gov (United States)

    Brown, Michael C; Gromeier, Matthias

    2015-05-01

    Achieving tumor-specific, robust, and durable effector cytotoxic immune responses is key to successful immunotherapy. This has been accomplished with adoptive cell transfer of ex vivo-expanded autologous tumor-infiltrating or engineered T cells, or with immune checkpoint inhibitors, enhancing inherent T cell reactivity. A natural ability to recruit effector responses makes tumor-targeting ('oncolytic') viruses attractive as immunotherapy vehicles. However, most viruses actively block inflammatory and immunogenic events; or, host innate immune responses may prevent immune initiating events in the first place. Moreover, the mechanisms of how virus infection can produce effector responses against host (tumor) neo-antigens are unclear. We are pioneering oncolytic immunotherapy based on poliovirus, which has no specific mechanism to interfere with host immune activation, exhibits lytic cytotoxicity in the presence of an antiviral interferon response and pre-existing immunity, and engages a powerful innate immune sensor implicated in recruiting cytotoxic T cell responses. Central to this approach is a unique confluence of factors that drive tumor-specific viral translation and cytotoxicity. PMID:26105699

  20. Treatment of colon cancer with oncolytic herpes simplex virus in preclinical models.

    Science.gov (United States)

    Yang, H; Peng, T; Li, J; Wang, Y; Zhang, W; Zhang, P; Peng, S; Du, T; Li, Y; Yan, Q; Liu, B

    2016-05-01

    Cancer stem cells (CSCs), which are a rare population in any type of cancer, including colon cancer, are tumorigenic and responsible for cancer recurrence and metastasis. CSCs have been isolated from a number of different solid tumors recently, although the isolation of CSCs in colon cancer is still challenging. We cultured colon cancer cells in stem cell medium to obtain colonosphere cells. These cells possessed the characteristics of CSCs, with a high capacity of tumorigenicity, migration and invasion in vitro and in vivo. The isolation and identification of CSCs have provided new targets for the therapeutics. Oncolytic herpes simplex viruses (oHSV) are an effective strategy for killing colon cancer cells in preclinical models. Here, we examined the efficacy of an oncolytic herpes simplex virus type 2 (oHSV2) in killing colon cancer cells and colon cancer stem-like cells (CSLCs). oHSV2 was found to be highly cytotoxic to the adherent and sphere cells in vitro, and oHSV2 treatment in vivo significantly inhibited tumor growth. This study demonstrates that oHSV2 is effective against colon cancer cells and colon CSLCs and could be a promising strategy for treating colon cancer patients. PMID:26871935

  1. Oncolytic adenoviruses kill breast cancer initiating CD44+CD24-/low cells.

    Science.gov (United States)

    Eriksson, Minna; Guse, Kilian; Bauerschmitz, Gerd; Virkkunen, Pekka; Tarkkanen, Maija; Tanner, Minna; Hakkarainen, Tanja; Kanerva, Anna; Desmond, Renee A; Pesonen, Sari; Hemminki, Akseli

    2007-12-01

    Cancer stem cells have been indicated in the initiation of tumors and are even found to be responsible for relapses after apparently curative therapies have been undertaken. In breast cancer, they may reside in the CD44(+)CD24(-/low) population. The use of oncolytic adenoviruses presents an attractive anti-tumor approach for eradication of these cells because their entry occurs through infection and they are, therefore, not susceptible to those mechanisms that commonly render stem cells resistant to many drugs. We isolated CD44(+)CD24(-/low) cells from patient pleural effusions and confirmed stem cell-like features including oct4 and sox2 expression and Hoechst 33342 exclusion. CD44(+)CD24(-/low) cells, including the Hoechst excluding subpopulation, could be effectively killed by oncolytic adenoviruses Ad5/3-Delta24 and Ad5.pk7-Delta24. In mice, CD44(+)CD24(-/low) cells formed orthotopic breast tumors but virus infection prevented tumor formation. Ad5/3-Delta24 and Ad5.pk7-Delta24 were effective against advanced orthotopic CD44(+)CD24(-/low)-derived tumors. In summary, Ad5/3-Delta24 and Ad5.pk7-Delta24 can kill CD44(+)CD24(-/low), and also committed breast cancer cells, making them promising agents for treatment of breast cancer. PMID:17848962

  2. Combined Treatment with an Oncolytic Adenovirus and Antitumor Activity of Vincristine against Retinoblastoma Cells

    Directory of Open Access Journals (Sweden)

    Xianqun Fan

    2012-08-01

    Full Text Available Treatment trends of retinoblastoma (RB have gradually evolved from eye enucleation and external radiation to local treatment. Combined treatment with an oncolytic virus and chemotherapy is currently a new method in RB treatment. To investigate the therapeutic effect of oncolytic adenovirus SG600 in combination with vincristine (VCR on retinoblastoma in vitro, the cell viability, cell cycle effects and apoptotic activity of HXO-RB44 cells treated with SG600, VCR or SG600 plus VCR were measured using a cell counting kit-8-based procedure and flow cytometry. Western blot analysis for Akt, p-Akt, p-p53 and p-Rb protein was performed to investigate the underlying mechanisms of combined therapy. The combination therapy exerted a synergistic antitumor effect via a type of G2/M and S phase arrest rather than the induction of apoptosis. The combination of VCR and SG600 further reduced Akt phosphorylation compared with cells treated with VCR alone, suggesting that SG600 could overcome chemoresistance, perhaps by down-regulating Akt in RB cells. An increase in the expression of p-p53 and decrease in p-Rb expression in HXO-RB44 after co-treatment might be associated with cell cycle block. Western blot examination revealed that VCR might enhance SG600 replication. These results suggest that viro-chemo combination therapy is a feasible and potentially promising approach for the treatment of retinoblastoma.

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

    Directory of Open Access Journals (Sweden)

    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.

  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. Pexa-Vec double agent engineered vaccinia: oncolytic and active immunotherapeutic.

    Science.gov (United States)

    Breitbach, Caroline J; Parato, Kelley; Burke, James; Hwang, Tae-Ho; Bell, John C; Kirn, David H

    2015-08-01

    Oncolytic immunotherapies (OI) selectively infect, amplify within and destroy cancer cells, thereby representing a novel class of anti-cancer therapy. In addition to this primary mechanism-of-action (MOA), OI based on vaccinia have been shown to selectively target tumor-associated vasculature, triggering an acute reduction in tumor perfusion. This review focuses on a third complementary MOA for this product class: the induction of active immunotherapy. While the active immunotherapy approach has been validated by recent product approvals, the field is still faced with significant challenges. Tumors have evolved diverse mechanisms to hide from immune-mediated destruction. Here we hypothesize that oncolytic immunotherapy replication within tumors may tip the immune balance to allow for the effective induction and execution of adaptive anti-tumor immunity, resulting in long-term tumor control following OI clearance. This immune activation against the cancer can be augmented through OI 'arming' for the expression of immunostimulatory transgene products from the virus genome. With the first vaccinia OI (Pexa-Vec, thymidine kinase-inactivated vaccinia expressing Granulocyte-colony stimulating factor [GM-CSF]) now in advanced-stage clinical trials, it has become more important than ever to understand the complimentary MOA that contributes to tumor destruction and control in patients. PMID:25900822

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

    International Nuclear Information System (INIS)

    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. 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. 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. 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

  7. Recombinant human brain natriuretic peptide attenuates trauma-/haemorrhagic shock-induced acute lung injury through inhibiting oxidative stress and the NF-κB-dependent inflammatory/MMP-9 pathway.

    Science.gov (United States)

    Song, Zhi; Zhao, Xiu; Liu, Martin; Jin, Hongxu; Wang, Ling; Hou, Mingxiao; Gao, Yan

    2015-12-01

    Acute lung injury (ALI) is one of the most serious complications in traumatic patients and is an important part of multiple organ dysfunction syndrome (MODS). Recombinant human brain natriuretic peptide (rhBNP) is a peptide with a wide range of biological activity. In this study, we investigated local changes in oxidative stress and the NF-κB-dependent matrix metalloproteinase-9 (MMP-9) pathway in rats with trauma/haemorrhagic shock (TH/S)-induced ALI and evaluated the effects of pretreatment with rhBNP. Forty-eight rats were randomly divided into four groups: sham operation group, model group, low-dosage rhBNP group and high-dosage rhBNP group (n = 12 for each group). Oxidative stress and MPO activity were measured by ELISA kits. MMP-9 activity was detected by zymography analysis. NF-κB activity was determined using Western blot assay. With rhBNP pretreatment, TH/S-induced protein leakage, increased MPO activity, lipid peroxidation and metalloproteinase (MMP)-9 activity were inhibited. Activation of antioxidative enzymes was reversed. The phosphorylation of NF-κB and the degradation of its inhibitor IκB were suppressed. The results suggested that the protection mechanism of rhBNP is possibly mediated through upregulation of anti-oxidative enzymes and inhibition of NF-κB activation. More studies are needed to further evaluate whether rhBNP is a suitable candidate as an effective inhaling drug to reduce the incidence of TH/S-induced ALI. PMID:26852688

  8. Intramuscular inoculation of mice with the live-attenuated recombinant rabies virus TriGAS results in a transient infection of the draining lymph nodes and a robust, long-lasting protective immune response against rabies.

    Science.gov (United States)

    Schutsky, Keith; Curtis, Dana; Bongiorno, Emily K; Barkhouse, Darryll A; Kean, Rhonda B; Dietzschold, Bernhard; Hooper, D Craig; Faber, Milosz

    2013-02-01

    A single intramuscular application of the live but not UV-inactivated recombinant rabies virus (RABV) variant TriGAS in mice induces the robust and sustained production of RABV-neutralizing antibodies that correlate with long-term protection against challenge with an otherwise lethal dose of the wild-type RABV. To obtain insight into the mechanism by which live TriGAS induces long-lasting protective immunity, quantitative PCR (qPCR) analysis of muscle tissue, draining lymph nodes, spleen, spinal cord, and brain at different times after TriGAS inoculation revealed the presence of significant copy numbers of RABV-specific RNA in muscle, lymph node, and to a lesser extent, spleen for several days postinfection. Notably, no significant amounts of RABV RNA were detected in brain or spinal cord at any time after TriGAS inoculation. Differential qPCR analysis revealed that the RABV-specific RNA detected in muscle is predominantly genomic RNA, whereas RABV RNA detected in draining lymph nodes is predominantly mRNA. Comparison of genomic RNA and mRNA obtained from isolated lymph node cells showed the highest mRNA-to-genomic-RNA ratios in B cells and dendritic cells (DCs), suggesting that these cells represent the major cell population that is infected in the lymph node. Since RABV RNA declined to undetectable levels by 14 days postinoculation of TriGAS, we speculate that a transient infection of DCs with TriGAS may be highly immunostimulatory through mechanisms that enhance antigen presentation. Our results support the superior efficacy and safety of TriGAS and advocate for its utility as a vaccine. PMID:23192867

  9. 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.)

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

    International Nuclear Information System (INIS)

    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.)

  11. DC attenuation meter

    Science.gov (United States)

    Hargrove, Douglas L.

    2004-09-14

    A portable, hand-held meter used to measure direct current (DC) attenuation in low impedance electrical signal cables and signal attenuators. A DC voltage is applied to the signal input of the cable and feedback to the control circuit through the signal cable and attenuators. The control circuit adjusts the applied voltage to the cable until the feedback voltage equals the reference voltage. The "units" of applied voltage required at the cable input is the system attenuation value of the cable and attenuators, which makes this meter unique. The meter may be used to calibrate data signal cables, attenuators, and cable-attenuator assemblies.

  12. Expression of RNA interference triggers from an oncolytic herpes simplex virus results in specific silencing in tumour cells in vitro and tumours in vivo

    International Nuclear Information System (INIS)

    Delivery of small interfering RNA (siRNA) to tumours remains a major obstacle for the development of RNA interference (RNAi)-based therapeutics. Following the promising pre-clinical and clinical results with the oncolytic herpes simplex virus (HSV) OncoVEXGM-CSF, we aimed to express RNAi triggers from oncolytic HSV, which although has the potential to improve treatment by silencing tumour-related genes, was not considered possible due to the highly oncolytic properties of HSV. To evaluate RNAi-mediated silencing from an oncolytic HSV backbone, we developed novel replicating HSV vectors expressing short-hairpin RNA (shRNA) or artificial microRNA (miRNA) against the reporter genes green fluorescent protein (eGFP) and β-galactosidase (lacZ). These vectors were tested in non-tumour cell lines in vitro and tumour cells that are moderately susceptible to HSV infection both in vitro and in mice xenografts in vivo. Silencing was assessed at the protein level by fluorescent microscopy, x-gal staining, enzyme activity assay, and western blotting. Our results demonstrate that it is possible to express shRNA and artificial miRNA from an oncolytic HSV backbone, which had not been previously investigated. Furthermore, oncolytic HSV-mediated delivery of RNAi triggers resulted in effective and specific silencing of targeted genes in tumour cells in vitro and tumours in vivo, with the viruses expressing artificial miRNA being comprehensibly more effective. This preliminary data provide the first demonstration of oncolytic HSV-mediated expression of shRNA or artificial miRNA and silencing of targeted genes in tumour cells in vitro and in vivo. The vectors developed in this study are being adapted to silence tumour-related genes in an ongoing study that aims to improve the effectiveness of oncolytic HSV treatment in tumours that are moderately susceptible to HSV infection and thus, potentially improve response rates seen in human clinical trials

  13. 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.

  14. Increased suppression of oncolytic adenovirus carrying mutant k5 on colorectal tumor

    International Nuclear Information System (INIS)

    Angiogenesis plays a key role in the development of a wide variety of malignant tumors. The approach of targeting antiangiogenesis has become an important field of cancer gene therapy. In this study, the antiangiogenesis protein K5 (the kringle 5 of human plasminogen) has been mutated by changing leucine71 to arginine to form mK5. Then the ZD55-mK5, which is an oncolytic adenovirus expressing mK5, was constructed. It showed stronger inhibition on proliferation of human umbilical vein endothelial cell. Moreover, in tube formation and embryonic chorioallantoic membrane assay, ZD55-mK5 exhibited more effective antiangiogenesis than ZD55-K5. In addition, ZD55-mK5 generated obvious suppression on the growth of colorectal tumor xenografts and prolonged the life span of nude mice. These results indicate that ZD55-mK5 is a potent agent for inhibiting the tumor angiogenesis and tumor growth

  15. 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.

  16. 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.

  17. Pressure surge attenuator

    Science.gov (United States)

    Christie, Alan M.; Snyder, Kurt I.

    1985-01-01

    A pressure surge attenuation system for pipes having a fluted region opposite crushable metal foam. As adapted for nuclear reactor vessels and heads, crushable metal foam is disposed to attenuate pressure surges.

  18. 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.

  19. Hepatoma targeting peptide conjugated bio-reducible polymer complexed with oncolytic adenovirus for cancer gene therapy.

    Science.gov (United States)

    Choi, Joung-Woo; Kim, Hyun Ah; Nam, Kihoon; Na, Youjin; Yun, Chae-Ok; Kim, SungWan

    2015-12-28

    Despite adenovirus (Ad) vector's numerous advantages for cancer gene therapy, such as high ability of endosomal escape, efficient nuclear entry mechanism, and high transduction, and therapeutic efficacy, tumor specific targeting and antiviral immune response still remain as a critical challenge in clinical setting. To overcome these obstacles and achieve cancer-specific targeting, we constructed tumor targeting bioreducible polymer, an arginine grafted bio-reducible polymer (ABP)-PEG-HCBP1, by conjugating PEGylated ABP with HCBP1 peptides which has high affinity and selectivity towards hepatoma. The ABP-PEG-HCBP1-conjugated replication incompetent GFP-expressing ad, (Ad/GFP)-ABP-PEG-HCBP1, showed a hepatoma cancer specific uptake and transduction compared to either naked Ad/GFP or Ad/GFP-ABP. Competition assays demonstrated that Ad/GFP-ABP-PEG-HCBP1-mediated transduction was specifically inhibited by HCBP1 peptide rather than coxsackie and adenovirus receptor specific antibody. In addition, ABP-PEG-HCBP1 can protect biological activity of Ad against serum, and considerably reduced both innate and adaptive immune response against Ad. shMet-expressing oncolytic Ad (oAd; RdB/shMet) complexed with ABP-PEG-HCBP1 delivered oAd efficiently into hepatoma cancer cells. The oAd/ABP-PEG-HCBP1 demonstrated enhanced cancer cell killing efficacy in comparison to oAd/ABP complex. Furthermore, Huh7 and HT1080 cancer cells treated with oAd/shMet-ABP-PEG-HCBP1 complex had significantly decreased Met and VEGF expression in hepatoma cancer, but not in non-hepatoma cancer. In sum, these results suggest that HCBP1-conjugated bioreducible polymer could be used to deliver oncolytic Ad safely and efficiently to treat hepatoma. PMID:26437261

  20. 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

  1. Dendritic cells and T cells deliver oncolytic reovirus for tumour killing despite pre-existing anti-viral immunity

    OpenAIRE

    Ilett, EJ; Prestwich, RJ; Kottke, T; Errington, F; Thompson, JM; Harrington, KJ; Pandha, HS; Coffey, M; Selby, PJ; Vile, RG; Melcher, AA

    2009-01-01

    Reovirus is a naturally occurring oncolytic virus currently in early clinical trials. However, the rapid induction of neutralizing antibodies represents a major obstacle to successful systemic delivery. This study addresses, for the first time, the ability of cellular carriers in the form of T cells and dendritic cells (DC) to protect reovirus from systemic neutralization. In addition, the ability of these cellular carriers to manipulate the subsequent balance of anti-viral versus anti-tumour...

  2. Choindroitinase ABC I-Mediated Enhancement of Oncolytic Virus Spread and Anti Tumor Efficacy: A Mathematical Model

    OpenAIRE

    Kim, Yangjin; Lee, Hyun Geun; Dmitrieva, Nina; Kim, Junseok; Kaur, Balveen; Friedman, Avner

    2014-01-01

    Oncolytic viruses are genetically engineered viruses that are designed to kill cancer cells while doing minimal damage to normal healthy tissue. After being injected into a tumor, they infect cancer cells, multiply inside them, and when a cancer cell is killed they move on to spread and infect other cancer cells. Chondroitinase ABC (Chase-ABC) is a bacterial enzyme that can remove a major glioma ECM component, chondroitin sulfate glycosoamino glycans from proteoglycans without any deleterious...

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

    OpenAIRE

    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...

  4. 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.

  5. Specific transfer of oncolytic adenoviruses by mesenchymal stem cells for the elimination of pancreatic tumour stem cells

    OpenAIRE

    KACZOROWSKI, ADAM

    2014-01-01

    Abstract Pancreatic adenocarcinoma has a very poor prognosis with currently existing therapies prolonging patient life for only a few weeks. Therefore novel therapy options are urgently needed. Present theories maintain that only a small fraction of tumour cells (the cancer stem cells (CSC)) are responsible for the highly aggressive behaviour of pancreatic cancer. These cells show a stem cell like phenotype and a high resistance to chemotherapy. Oncolytic viruses are promising candidat...

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

    Science.gov (United States)

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

    2014-08-01

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

  7. The in vivo therapeutic efficacy of the oncolytic adenovirus Delta24-RGD is mediated by tumor-specific immunity.

    Directory of Open Access Journals (Sweden)

    Anne Kleijn

    Full Text Available The oncolytic adenovirus Delta24-RGD represents a new promising therapeutic agent for patients with a malignant glioma and is currently under investigation in clinical phase I/II trials. Earlier preclinical studies showed that Delta24-RGD is able to effectively lyse tumor cells, yielding promising results in various immune-deficient glioma models. However, the role of the immune response in oncolytic adenovirus therapy for glioma has never been explored. To this end, we assessed Delta24-RGD treatment in an immune-competent orthotopic mouse model for glioma and evaluated immune responses against tumor and virus. Delta24-RGD treatment led to long-term survival in 50% of mice and this effect was completely lost upon administration of the immunosuppressive agent dexamethasone. Delta24-RGD enhanced intra-tumoral infiltration of F4/80+ macrophages, CD4+ and CD8+ T-cells, and increased the local production of pro-inflammatory cytokines and chemokines. In treated mice, T cell responses were directed to the virus as well as to the tumor cells, which was reflected in the presence of protective immunological memory in mice that underwent tumor rechallenge. Together, these data provide evidence that the immune system plays a vital role in the therapeutic efficacy of oncolytic adenovirus therapy of glioma, and may provide angles to future improvements on Delta24-RGD therapy.

  8. Oncolytic adenovirus mediated Survivin knockdown by RNA interference suppresses human colorectal carcinoma growth in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Wang Chun-Yi

    2009-06-01

    Full Text Available Abstract Background Colorectal cancer is a one of the most common alimentary malignancies. Survivin has been proved by many studies to be an ideal target for cancer gene therapy because of its strong anti-apoptotic effect. The reduction of Survivin expression by means of chemically synthesized small interfering RNA or small hairpin RNA expressed from plasmid and resulted growth inhibition of cancer cells had been proved by many studies including ours, but the transfection efficiency was not encouraging. So for the first time we constructed the Survivin shRNA into an oncolytic adenovirus, tested its effects on colorectal cancer cell lines and nude mice xenograft model. Methods In this study, we constructed an oncolytic adenovirus with a Survivin targeted small hairpin RNA and a reporter gene (ZD55-Sur-EGFP. The expression of Survivin mRNA and protein were analyzed by RT-PCR and western blot. The cell growth and apoptosis were tested by in vitro cytopathic assay, MTT assay and flow cytometry respectively. The effect of the constructed virus on xenograft model was evaluated by tumor volume and western blot analysis. Results ZD55-Sur-EGFP replicated in cancer cells specifically, reduced the expression of Survivin mRNA and protein expression effectively (P Conclusion We conclude Survivin RNA interference combining with oncolytic adenovirus virotherapy to be a promising treatment for colorectal cancer.

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

    OpenAIRE

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

    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.

  10. Recombinant DNA in Medicine

    OpenAIRE

    Cederbaum, Stephen D.; Fareed, George C.; Lovett, Michael A.; Shapiro, Larry J.

    1984-01-01

    Studies in bacteria and bacterial viruses have led to methods to manipulate and recombine DNA in unique and reproducible ways and to amplify these recombined molecules millions of times. Once properly identified, the recombinant DNA molecules can be used in various ways useful in medicine and human biology. There are many applications for recombinant DNA technology. Cloned complementary DNA has been used to produce various human proteins in microorganisms. Insulin and growth hormone have been...

  11. Improving baculovirus recombination

    OpenAIRE

    Zhao, Yuguang; Chapman, David A. G.; Jones, Ian M.

    2003-01-01

    Recombinant baculoviruses have established themselves as a favoured technology for the high-level expression of recombinant proteins. The construction of recombinant viruses, however, is a time consuming step that restricts consideration of the technology for high throughput developments. Here we use a targeted gene knockout technology to inactivate an essential viral gene that lies adjacent to the locus used for recombination. Viral DNA prepared from the knockout fails to initiate an infecti...

  12. Isolated limb perfusion with biochemotherapy and oncolytic virotherapy combines with radiotherapy and surgery to overcome treatment resistance in an animal model of extremity soft tissue sarcoma.

    Science.gov (United States)

    Wilkinson, Michelle J; Smith, Henry G; Pencavel, Timothy D; Mansfield, David C; Kyula-Currie, Joan; Khan, Aadil A; McEntee, Gráinne; Roulstone, Victoria; Hayes, Andrew J; Harrington, Kevin J

    2016-09-15

    The management of locally advanced or recurrent extremity sarcoma often necessitates multimodal therapy to preserve a limb, of which isolated limb perfusion (ILP) is a key component. However, with standard chemotherapeutic agents used in ILP, the duration of response is limited. Novel agents or treatment combinations are urgently needed to improve outcomes. Previous work in an animal model has demonstrated the efficacy of oncolytic virotherapy when delivered by ILP and, in this study, we report further improvements from combining ILP-delivered oncolytic virotherapy with radiation and surgical resection. In vitro, the combination of radiation with an oncolytic vaccinia virus (GLV-1h68) and melphalan demonstrated increased cytotoxicity in a panel of sarcoma cell lines. The effects were mediated through activation of the intrinsic apoptotic pathway. In vivo, combinations of radiation, oncolytic virotherapy and standard ILP resulted in delayed tumour growth and prolonged survival when compared with standard ILP alone. However, local disease control could only be secured when such treatment was combined with surgical resection, the timing of which was crucial in determining outcome. Combinations of oncolytic virotherapy with surgical resection and radiation have direct clinical relevance in extremity sarcoma and represent an exciting prospect for improving outcomes in this pathology. PMID:27116656

  13. 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…

  14. Variable laser attenuator

    Science.gov (United States)

    Foltyn, Stephen R.

    1988-01-01

    The disclosure relates to low loss, high power variable attenuators comprng one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength.

  15. Photoionization and Recombination

    Science.gov (United States)

    Nahar, Sultana N.

    2000-01-01

    Theoretically self-consistent calculations for photoionization and (e + ion) recombination are described. The same eigenfunction expansion for the ion is employed in coupled channel calculations for both processes, thus ensuring consistency between cross sections and rates. The theoretical treatment of (e + ion) recombination subsumes both the non-resonant recombination ("radiative recombination"), and the resonant recombination ("di-electronic recombination") processes in a unified scheme. In addition to the total, unified recombination rates, level-specific recombination rates and photoionization cross sections are obtained for a large number of atomic levels. Both relativistic Breit-Pauli, and non-relativistic LS coupling, calculations are carried out in the close coupling approximation using the R-matrix method. Although the calculations are computationally intensive, they yield nearly all photoionization and recombination parameters needed for astrophysical photoionization models with higher precision than hitherto possible, estimated at about 10-20% from comparison with experimentally available data (including experimentally derived DR rates). Results are electronically available for over 40 atoms and ions. Photoionization and recombination of He-, and Li-like C and Fe are described for X-ray modeling. The unified method yields total and complete (e+ion) recombination rate coefficients, that can not otherwise be obtained theoretically or experimentally.

  16. Recombineering Homologous Recombination Constructs in Drosophila

    OpenAIRE

    Carreira-Rosario, Arnaldo; Scoggin, Shane; Shalaby, Nevine A.; Williams, Nathan David; Hiesinger, P. Robin; Buszczak, Michael

    2013-01-01

    The continued development of techniques for fast, large-scale manipulation of endogenous gene loci will broaden the use of Drosophila melanogaster as a genetic model organism for human-disease related research. Recent years have seen technical advancements like homologous recombination and recombineering. However, generating unequivocal null mutations or tagging endogenous proteins remains a substantial effort for most genes. Here, we describe and demonstrate techniques for using recombineeri...

  17. Expression of RNA interference triggers from an oncolytic herpes simplex virus results in specific silencing in tumour cells in vitro and tumours in vivo

    Directory of Open Access Journals (Sweden)

    Anesti Anna-Maria

    2010-09-01

    Full Text Available Abstract Background Delivery of small interfering RNA (siRNA to tumours remains a major obstacle for the development of RNA interference (RNAi-based therapeutics. Following the promising pre-clinical and clinical results with the oncolytic herpes simplex virus (HSV OncoVEXGM-CSF, we aimed to express RNAi triggers from oncolytic HSV, which although has the potential to improve treatment by silencing tumour-related genes, was not considered possible due to the highly oncolytic properties of HSV. Methods To evaluate RNAi-mediated silencing from an oncolytic HSV backbone, we developed novel replicating HSV vectors expressing short-hairpin RNA (shRNA or artificial microRNA (miRNA against the reporter genes green fluorescent protein (eGFP and β-galactosidase (lacZ. These vectors were tested in non-tumour cell lines in vitro and tumour cells that are moderately susceptible to HSV infection both in vitro and in mice xenografts in vivo. Silencing was assessed at the protein level by fluorescent microscopy, x-gal staining, enzyme activity assay, and western blotting. Results Our results demonstrate that it is possible to express shRNA and artificial miRNA from an oncolytic HSV backbone, which had not been previously investigated. Furthermore, oncolytic HSV-mediated delivery of RNAi triggers resulted in effective and specific silencing of targeted genes in tumour cells in vitro and tumours in vivo, with the viruses expressing artificial miRNA being comprehensibly more effective. Conclusions This preliminary data provide the first demonstration of oncolytic HSV-mediated expression of shRNA or artificial miRNA and silencing of targeted genes in tumour cells in vitro and in vivo. The vectors developed in this study are being adapted to silence tumour-related genes in an ongoing study that aims to improve the effectiveness of oncolytic HSV treatment in tumours that are moderately susceptible to HSV infection and thus, potentially improve response rates seen

  18. A Proteoliposome Containing Apolipoprotein A-I Mutant (V156K) Enhances Rapid Tumor Regression Activity of Human Origin Oncolytic Adenovirus in Tumor-Bearing Zebrafish and Mice

    OpenAIRE

    Seo, Juyi; Yun, Chae-Ok; Kwon, Oh-Joon; Choi, Eun-Jin; Song, Jae-Young; Choi, Inho; Cho, Kyung-Hyun

    2012-01-01

    We recently reported that the efficiency of adenoviral gene delivery and virus stability are significantly enhanced when a proteoliposome (PL) containing apolipoprotein (apo) A-I is used in an animal model. In the current study, we tested tumor removal activity of oncolytic adenovirus (Ad) using PL-containing wildtype (WT) or V156K. Oncolytic Ad with or without PL was injected into tumors of zebrafish and nude mice as a Hep3B tumor xenograft model. The V156K-PL-Ad-injected zebrafish, group sh...

  19. Fundamental study of recombination and recombineering in Escherichia coli

    OpenAIRE

    Sun, Xiaohang; Huang, Yang

    2008-01-01

    Recombination and recombineering systems have been used in Escherichia coli to recombinant DNA sequences. With endonuclease and DNA lipase the bacterial plasmid and target DNA fragment can bind together and recombinant for a new DNA sequences. Red Proteins have been used in recombineering system to perform the function as the enzymes in recombination system, and faster and easier than the other way of recombinant new DNA sequences in E.coli. In this report we get to know the pr...

  20. 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.

  1. 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.

  2. Horizontal Transmissible Protection against Myxomatosis and Rabbit Hemorrhagic Disease by Using a Recombinant Myxoma Virus

    OpenAIRE

    Bárcena, Juan; Morales, Mónica; Vázquez, Belén; Boga, José A.; Parra, Francisco; Lucientes, Javier; Pagès-Manté, Albert; Sánchez-Vizcaíno, José M.; Blasco, Rafael; Torres, Juan M.

    2000-01-01

    We have developed a new strategy for immunization of wild rabbit populations against myxomatosis and rabbit hemorrhagic disease (RHD) that uses recombinant viruses based on a naturally attenuated field strain of myxoma virus (MV). The recombinant viruses expressed the RHDV major capsid protein (VP60) including a linear epitope tag from the transmissible gastroenteritis virus (TGEV) nucleoprotein. Following inoculation, the recombinant viruses induced specific antibody responses against MV, RH...

  3. MicroRNA-Attenuated Clone of Virulent Semliki Forest Virus Overcomes Antiviral Type I Interferon in Resistant Mouse CT-2A Glioma

    Science.gov (United States)

    Martikainen, Miika; Niittykoski, Minna; von und zu Fraunberg, Mikael; Immonen, Arto; Koponen, Susanna; van Geenen, Maartje; Vähä-Koskela, Markus; Ylösmäki, Erkko; Jääskeläinen, Juha E.; Saksela, Kalle

    2015-01-01

    ABSTRACT Glioblastoma is a terminal disease with no effective treatment currently available. Among the new therapy candidates are oncolytic viruses capable of selectively replicating in cancer cells, causing tumor lysis and inducing adaptive immune responses against the tumor. However, tumor antiviral responses, primarily mediated by type I interferon (IFN-I), remain a key problem that severely restricts viral replication and oncolysis. We show here that the Semliki Forest virus (SFV) strain SFV4, which causes lethal encephalitis in mice, is able to infect and replicate independent of the IFN-I defense in mouse glioblastoma cells and cell lines originating from primary human glioblastoma patient samples. The ability to tolerate IFN-I was retained in SFV4-miRT124 cells, a derivative cell line of strain SFV4 with a restricted capacity to replicate in neurons due to insertion of target sites for neuronal microRNA 124. The IFN-I tolerance was associated with the viral nsp3-nsp4 gene region and distinct from the genetic loci responsible for SFV neurovirulence. In contrast to the naturally attenuated strain SFV A7(74) and its derivatives, SFV4-miRT124 displayed increased oncolytic potency in CT-2A murine astrocytoma cells and in the human glioblastoma cell lines pretreated with IFN-I. Following a single intraperitoneal injection of SFV4-miRT124 into C57BL/6 mice bearing CT-2A orthotopic gliomas, the virus homed to the brain and was amplified in the tumor, resulting in significant tumor growth inhibition and improved survival. IMPORTANCE Although progress has been made in development of replicative oncolytic viruses, information regarding their overall therapeutic potency in a clinical setting is still lacking. This could be at least partially dependent on the IFN-I sensitivity of the viruses used. Here, we show that the conditionally replicating SFV4-miRT124 virus shares the IFN-I tolerance of the pathogenic wild-type SFV, thereby allowing efficient targeting of a glioma

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

    OpenAIRE

    Zhuang Xiufen; Zhang Wen; Chen Yatong; Han Xiangping; Li Jie; Zhang Yu; Zhang Youhui; Zhang Shuren; Liu Binlei

    2012-01-01

    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, ALDHb...

  5. An Oncolytic Adenovirus Enhanced for Toll-like Receptor 9 Stimulation Increases Antitumor Immune Responses and Tumor Clearance

    OpenAIRE

    Cerullo, Vincenzo; Diaconu, Iulia; Romano, Valentina; Hirvinen, Mari; Ugolini, Matteo; Escutenaire, Sophie; Holm, Sirkka-Liisa; Kipar, Anja; Kanerva, Anna; Hemminki, Akseli

    2012-01-01

    Oncolytic viruses represent a multifaceted tool for cancer treatment. In addition to specific killing of cancer cells (oncolysis), these agents also provide danger signals prompting the immune system to stimulate an antitumor immune response. To increase adenovirus adjuvancy, we engineered the genome of Ad5D24 by inserting 18 immunostimulatory islands (Ad5D24-CpG). The toxicity and immunogenicity profile of Ad5D24-CpG showed that the safety of the maternal virus was retained. The efficacy of ...

  6. 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.

  7. RADIO FREQUENCY ATTENUATOR

    Science.gov (United States)

    Giordano, S.

    1963-11-12

    A high peak power level r-f attenuator that is readily and easily insertable along a coaxial cable having an inner conductor and an outer annular conductor without breaking the ends thereof is presented. Spaced first and second flares in the outer conductor face each other with a slidable cylindrical outer conductor portion therebetween. Dielectric means, such as water, contact the cable between the flares to attenuate the radio-frequency energy received thereby. The cylindrical outer conductor portion is slidable to adjust the voltage standing wave ratio to a low level, and one of the flares is slidable to adjust the attenuation level. An integral dielectric container is also provided. (AFC)

  8. Attenuator And Conditioner

    Science.gov (United States)

    Anderson, Gene R.; Armendariz, Marcelino G.; Carson, Richard F.; Bryan, Robert P.; Duckett, III, Edwin B.; Kemme, Shanalyn Adair; McCormick, Frederick B.; Peterson, David W.

    2006-04-04

    An apparatus and method of attenuating and/or conditioning optical energy for an optical transmitter, receiver or transceiver module is disclosed. An apparatus for attenuating the optical output of an optoelectronic connector including: a mounting surface; an array of optoelectronic devices having at least a first end; an array of optical elements having at least a first end; the first end of the array of optical elements optically aligned with the first end of the array of optoelectronic devices; an optical path extending from the first end of the array of optoelectronic devices and ending at a second end of the array of optical elements; and an attenuator in the optical path for attenuating the optical energy emitted from the array of optoelectronic devices. Alternatively, a conditioner may be adapted in the optical path for conditioning the optical energy emitted from the array of optoelectronic devices.

  9. Productive homologous and non-homologous recombination of hepatitis C virus in cell culture.

    Directory of Open Access Journals (Sweden)

    Troels K H Scheel

    2013-03-01

    Full Text Available Genetic recombination is an important mechanism for increasing diversity of RNA viruses, and constitutes a viral escape mechanism to host immune responses and to treatment with antiviral compounds. Although rare, epidemiologically important hepatitis C virus (HCV recombinants have been reported. In addition, recombination is an important regulatory mechanism of cytopathogenicity for the related pestiviruses. Here we describe recombination of HCV RNA in cell culture leading to production of infectious virus. Initially, hepatoma cells were co-transfected with a replicating JFH1ΔE1E2 genome (genotype 2a lacking functional envelope genes and strain J6 (2a, which has functional envelope genes but does not replicate in culture. After an initial decrease in the number of HCV positive cells, infection spread after 13-36 days. Sequencing of recovered viruses revealed non-homologous recombinants with J6 sequence from the 5' end to the NS2-NS3 region followed by JFH1 sequence from Core to the 3' end. These recombinants carried duplicated sequence of up to 2400 nucleotides. HCV replication was not required for recombination, as recombinants were observed in most experiments even when two replication incompetent genomes were co-transfected. Reverse genetic studies verified the viability of representative recombinants. After serial passage, subsequent recombination events reducing or eliminating the duplicated region were observed for some but not all recombinants. Furthermore, we found that inter-genotypic recombination could occur, but at a lower frequency than intra-genotypic recombination. Productive recombination of attenuated HCV genomes depended on expression of all HCV proteins and tolerated duplicated sequence. In general, no strong site specificity was observed. Non-homologous recombination was observed in most cases, while few homologous events were identified. A better understanding of HCV recombination could help identification of natural

  10. 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.

  11. Case–Control Estimation of the Impact of Oncolytic Adenovirus on the Survival of Patients With Refractory Solid Tumors

    Science.gov (United States)

    Kanerva, Anna; Koski, Anniina; Liikanen, Ilkka; Oksanen, Minna; Joensuu, Timo; Hemminki, Otto; Palmgren, Juni; Hemminki, Kari; Hemminki, Akseli

    2015-01-01

    Oncolytic immunotherapy with cytokine armed replication competent viruses is an emerging approach in cancer treatment. In a recent randomized trial, an increase in response rate was seen but the effect on overall survival is not known with any virus. To facilitate randomized trials, we performed a case–control study assessing the survival of 270 patients treated in an Advanced Therapy Access Program (ATAP), in comparison to matched concurrent controls from the same hospital. The overall survival of all virus treated patients was not increased over controls. However, when analysis was restricted to GMCSF-sensitive tumor types treated with GMSCF-coding viruses, a significant improvement in median survival was present (from 170 to 208 days, P = 0.0012, N = 148). An even larger difference was seen when analysis was restricted to good performance score patients (193 versus 292 days, P = 0.034, N = 90). The survival of ovarian cancer patients was especially promising as median survival nearly quadrupled (P = 0.0003, N = 37). These preliminary data lend support to initiation of randomized clinical trials with GMCSF-coding oncolytic adenoviruses. PMID:25381801

  12. Case-control estimation of the impact of oncolytic adenovirus on the survival of patients with refractory solid tumors.

    Science.gov (United States)

    Kanerva, Anna; Koski, Anniina; Liikanen, Ilkka; Oksanen, Minna; Joensuu, Timo; Hemminki, Otto; Palmgren, Juni; Hemminki, Kari; Hemminki, Akseli

    2015-02-01

    Oncolytic immunotherapy with cytokine armed replication competent viruses is an emerging approach in cancer treatment. In a recent randomized trial, an increase in response rate was seen but the effect on overall survival is not known with any virus. To facilitate randomized trials, we performed a case-control study assessing the survival of 270 patients treated in an Advanced Therapy Access Program (ATAP), in comparison to matched concurrent controls from the same hospital. The overall survival of all virus treated patients was not increased over controls. However, when analysis was restricted to GMCSF-sensitive tumor types treated with GMSCF-coding viruses, a significant improvement in median survival was present (from 170 to 208 days, P = 0.0012, N = 148). An even larger difference was seen when analysis was restricted to good performance score patients (193 versus 292 days, P = 0.034, N = 90). The survival of ovarian cancer patients was especially promising as median survival nearly quadrupled (P = 0.0003, N = 37). These preliminary data lend support to initiation of randomized clinical trials with GMCSF-coding oncolytic adenoviruses. PMID:25381801

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

    Science.gov (United States)

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

    2014-09-15

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

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

    International Nuclear Information System (INIS)

    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

  15. A cancer-favoring oncolytic vaccinia virus shows enhanced suppression of stem-cell like colon cancer

    Science.gov (United States)

    Yoo, So Young; Bang, Seo Young; Jeong, Su-Nam; Kang, Dae Hwan; Heo, Jeong

    2016-01-01

    Stem cell-like colon cancer cells (SCCs) pose a major challenge in colon cancer treatment because of their resistance to chemotherapy and radiotherapy. Oncolytic virus-based therapy has shown promising results in uncured cancer patients; however, its effects on SCCs are not well studied yet. Here, we engineered a cancer-favoring oncolytic vaccinia virus (CVV) as a potent biotherapeutic and investigated its therapeutic efficacy in terms of killing SCCs. CVV is an evolved Wyeth strain vaccinia virus (EVV) lacking the viral thymidine kinase. SCC models were established using human or mouse colon cancer spheres, which continuously expressed stemness markers. The cancer-favoring characteristics and different cytotoxic pathways for killing cancer cells successfully overrode general drug resistance, thereby killing colon cancer cells regardless of the presence of SCCs. Subcutaneously injected HT29 spheres showed lower growth in CVV-treated models than in 5-Fu-treated models. Intraperitoneally injected CT26 spheres induced tumor masses in the abdominal region. CVV-treated groups showed higher survival rates and smaller tumor mass formation, compared to 5-Fu-treated groups. Interestingly, the combined treatment of CVV with 5-Fu showed improved survival rates and complete suppression of tumor mass. The CVV developed in this study, thus, effectively suppresses SCCs, which can be synergistically enhanced by simultaneous treatment with the anticancer drug 5-Fu. Our novel CVV is highly advantageous as a next-generation therapeutic for treating colon cancer. PMID:26918725

  16. An oncolytic adenovirus enhanced for toll-like receptor 9 stimulation increases antitumor immune responses and tumor clearance.

    Science.gov (United States)

    Cerullo, Vincenzo; Diaconu, Iulia; Romano, Valentina; Hirvinen, Mari; Ugolini, Matteo; Escutenaire, Sophie; Holm, Sirkka-Liisa; Kipar, Anja; Kanerva, Anna; Hemminki, Akseli

    2012-11-01

    Oncolytic viruses represent a multifaceted tool for cancer treatment. In addition to specific killing of cancer cells (oncolysis), these agents also provide danger signals prompting the immune system to stimulate an antitumor immune response. To increase adenovirus adjuvancy, we engineered the genome of Ad5D24 by inserting 18 immunostimulatory islands (Ad5D24-CpG). The toxicity and immunogenicity profile of Ad5D24-CpG showed that the safety of the maternal virus was retained. The efficacy of the CpG-enriched virus was assessed in a xenograft model of lung cancer where a significant increase in antitumor effect was seen in comparison with controls. When the experiment was repeated in animal depleted of natural killer (NK) cells, Ad5D24-CpG lost its advantage. The same was seen when Toll-like receptor (TLR)9 was blocked systemically. In a syngeneic model of melanoma (B16-OVA), we observed a significant increase of OVA-specific T cells and a decrease of activation of myeloid-derived suppressor cells in Ad5D24-CpG-treated mice. In conclusion, we have generated the first genetically modified oncolytic adenovirus backbone able to enhance TLR9-stimulation for increased antitumor activity. PMID:22828500

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

    Science.gov (United States)

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

    2015-10-01

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

  18. Radiofrequency attenuator and method

    Science.gov (United States)

    Warner, Benjamin P.; McCleskey, T. Mark; Burrell, Anthony K.; Agrawal, Anoop; Hall, Simon B.

    2009-11-10

    Radiofrequency attenuator and method. The attenuator includes a pair of transparent windows. A chamber between the windows is filled with molten salt. Preferred molten salts include quarternary ammonium cations and fluorine-containing anions such as tetrafluoroborate (BF.sub.4.sup.-), hexafluorophosphate (PF.sub.6.sup.-), hexafluoroarsenate (AsF.sub.6.sup.-), trifluoromethylsulfonate (CF.sub.3SO.sub.3.sup.-), bis(trifluoromethylsulfonyl)imide ((CF.sub.3SO.sub.2).sub.2N.sup.-), bis(perfluoroethylsulfonyl)imide ((CF.sub.3CF.sub.2SO.sub.2).sub.2N.sup.-) and tris(trifluoromethylsulfonyl)methide ((CF.sub.3SO.sub.2).sub.3 C.sup.-). Radicals or radical cations may be added to or electrochemically generated in the molten salt to enhance the RF attenuation.

  19. Expression of Recombinant Antibodies

    OpenAIRE

    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 transg...

  20. An oncolytic adenovirus in combination with radiation treatment (RT) for nasopharyngeal carcinoma (NPC)

    International Nuclear Information System (INIS)

    We have succeeded in regulating gene expression in nasopharyngeal carcinoma (NPC) by exploiting the exclusive presence of the Epstein Barr virus (EBV) genome in the cancer cells. When the latently expressed EBV-gene product, EBNA-1, binds to a family of repeats (FR) sequence, located in the oriP of the EBV genome (oriP-FR), this results in transcriptional activation of downstream genes. Based on these observations we designed a transcriptional targeting strategy that now allows for the construction of a conditionally replicating adenovirus under the control of the oriP-FR promoter. Results: Cloning the E1A transcriptional unit downstream of the EBV-responsive, oriP-FR promoter sequence generated the novel adenovirus adv.oriP.E1A. E1A protein expression using Western blot analysis demonstrated a time-dependent increase in expression in the EBV-positive C666-1 cells, in contrast to minimal expression in EBV-negative NPC cells. The MTT assay showed a dose-dependent cytotoxic effect of adv.oriP.E1A in the C666-1 cells, and the combination with 6 Gy of ionizing radiation resulted in an additive cytotoxic effect. In contrast, no evidence of cytotoxicity was observed in a panel of four other human cell lines after adv.oriP.E1A treatment. Western blotting for adenoviral fiber knob protein demonstrated a time-dependent increase in expression, consistent with viral replication; this was confirmed using quantitative real-time PCR. Ex-vivo infection of C666-1 cells with adv.oriP.E1A inhibited tumor formation for at least 100 days after intramuscular injection as compared to control cells that established palpable tumors one week after injection. Treatment of established C666-1 tumours with six intratumoral injections of 2 x 109 pfu adv.oriP.E1A in combination with 2 x 4 Gy radiation therapy (RT) resulted in complete regression for 3-weeks. Conclusion: We have successfully constructed a novel selectively oncolytic virus for EBV-positive NPC cells, demonstrating significant

  1. Pressure surge attenuator

    International Nuclear Information System (INIS)

    A pressure surge attenuation arrangement comprises crushable metal foam disposed adjacent regions adapted to be expanded by a pressure surge. In a pipe system such region consists of a thin walled inner pipe surrounded by a housing with crushable metal foam disposed in the space between the housing and the inner pipe. (author)

  2. Tritium Attenuation by Distillation

    International Nuclear Information System (INIS)

    The objective of this study was to determine how a 100 Area distillation system could be used to reduce to a satisfactory low value the tritium content of the dilute moderator produced in the 100 Area stills, and whether such a tritium attenuator would have sufficient capacity to process all this material before it is sent to the 400 Area for reprocessing

  3. Natural attenuation of herbicides

    DEFF Research Database (Denmark)

    Tuxen, Nina; Højberg, Anker Lajer; Broholm, Mette Martina;

    2002-01-01

    A field injection experiment in a sandy, aerobic aquifer showed that two phenoxy acids MCPP (mecoprop) and dichlorprop were degraded within I in downgradient of the injection wells after an apparent lag period. The plume development and microbial measurements indicated that microbial growth gover...... observations may be important for application of natural attenuation as a remedy in field scale systems....

  4. 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

  5. DNA-launched live-attenuated vaccines for biodefense applications.

    Science.gov (United States)

    Pushko, Peter; Lukashevich, Igor S; Weaver, Scott C; Tretyakova, Irina

    2016-09-01

    A novel vaccine platform uses DNA immunization to launch live-attenuated virus vaccines in vivo. This technology has been applied for vaccine development against positive-strand RNA viruses with global public health impact including alphaviruses and flaviviruses. The DNA-launched vaccine represents the recombinant plasmid that encodes the full-length genomic RNA of live-attenuated virus downstream from a eukaryotic promoter. When administered in vivo, the genomic RNA of live-attenuated virus is transcribed. The RNA initiates limited replication of a genetically defined, live-attenuated vaccine virus in the tissues of the vaccine recipient, thereby inducing a protective immune response. This platform combines the strengths of reverse genetics, DNA immunization and the advantages of live-attenuated vaccines, resulting in a reduced chance of genetic reversions, increased safety, and improved immunization. With this vaccine technology, the field of DNA vaccines is expanded from those that express subunit antigens to include a novel type of DNA vaccines that launch live-attenuated viruses. PMID:27055100

  6. Institutional Animal Care and Use Committee Considerations Regarding the Use of Virus-Induced Carcinogenesis and Oncolytic Viral Models.

    Science.gov (United States)

    Lewis, Stephanie D; Hickman-Davis, Judy M; Bergdall, Valerie K

    2016-03-31

    The use of virus-induced carcinogenesis and oncologic experimental animal models is essential in understanding the mechanisms of cancer development to advance prevention, diagnosis, and treatment methods. The Institutional Animal Care and Use Committee (IACUC) is responsible for both the complex philosophical and practical considerations associated with animal models of cancer. Animal models of cancer carry their own unique issues that require special consideration from the IACUC. Many of the considerations to be discussed apply to cancer models in general; specific issues related to viral carcinogenesis or oncolytic viruses will be specifically discussed as they arise. Responsible animal use integrates good science, humane care, and regulatory compliance. To meet those standards, the IACUC, in conjunction with the research investigator and attending veterinarian, must address a wide range of issues, including animal model selection, cancer model selection, humane end point considerations, experimental considerations, postapproval monitoring, reporting requirements, and animal management and personnel safety considerations. PMID:27034398

  7. Cell-based delivery of oncolytic viruses: a new strategic alliance for a biological strike against cancer.

    Science.gov (United States)

    Power, Anthony T; Bell, John C

    2007-04-01

    Recent years have seen tremendous advances in the development of exquisitely targeted replicating virotherapeutics that can safely destroy malignant cells. Despite this promise, clinical advancement of this powerful and unique approach has been hindered by vulnerability to host defenses and inefficient systemic delivery. However, it now appears that delivery of oncolytic viruses within carrier cells may offer one solution to this critical problem. In this review, we compare the advantages and limitations of the numerous cell lineages that have been investigated as delivery platforms for viral therapeutics, and discuss examples showing how combined cell-virus biotherapeutics can be used to achieve synergistic gains in antitumor activity. Finally, we highlight avenues for future preclinical research that might be taken in order to refine cell-virus biotherapeutics in preparation for human trials. PMID:17264852

  8. A compact rotary vane attenuator

    Science.gov (United States)

    Nixon, D. L.; Otosh, T. Y.; Stelzried, C. T.

    1969-01-01

    Rotary vane attenuator, when used as a front end attenuator, introduces an insertion loss that is proportional to the angle of rotation. New technique allows the construction of a shortened compact unit suitable for most installations.

  9. Photon attenuation by intensifying screens

    International Nuclear Information System (INIS)

    The photon attenuation by intensifying screens of different chemical composition has been determined. The attenuation of photons between 20 keV and 120 keV was measured by use of a multi-channel analyzer and a broad bremsstrahlung distribution. The attenuation by the intensifying screens was hereby determined simultaneously at many different monoenergetic photon energies. Experimentally determined attenuations were found to agree well with attenuation calculated from mass attenuation coefficients. The attenuation by the screens was also determined at various bremsstrahlung distributions, simulating those occurring behind the patient in various diagnostic X-ray examinations. The high attenuation in some of the intensifying screens form the basis for an analysis of the construction of asymmetric screen pairs. Single screen systems are suggested as a favourable alternative to thick screen pair systems. (Author)

  10. Choindroitinase ABC I-mediated enhancement of oncolytic virus spread and anti tumor efficacy: a mathematical model.

    Directory of Open Access Journals (Sweden)

    Yangjin Kim

    Full Text Available Oncolytic viruses are genetically engineered viruses that are designed to kill cancer cells while doing minimal damage to normal healthy tissue. After being injected into a tumor, they infect cancer cells, multiply inside them, and when a cancer cell is killed they move on to spread and infect other cancer cells. Chondroitinase ABC (Chase-ABC is a bacterial enzyme that can remove a major glioma ECM component, chondroitin sulfate glycosoamino glycans from proteoglycans without any deleterious effects in vivo. It has been shown that Chase-ABC treatment is able to promote the spread of the viruses, increasing the efficacy of the viral treatment. In this paper we develop a mathematical model to investigate the effect of the Chase-ABC on the treatment of glioma by oncolytic viruses (OV. We show that the model's predictions agree with experimental results for a spherical glioma. We then use the model to test various treatment options in the heterogeneous microenvironment of the brain. The model predicts that separate injections of OV, one into the center of the tumor and another outside the tumor will result in better outcome than if the total injection is outside the tumor. In particular, the injection of the ECM-degrading enzyme (Chase-ABC on the periphery of the main tumor core need to be administered in an optimal strategy in order to infect and eradicate the infiltrating glioma cells outside the tumor core in addition to proliferative cells in the bulk of tumor core. The model also predicts that the size of tumor satellites and distance between the primary tumor and multifocal/satellite lesions may be an important factor for the efficacy of the viral therapy with Chase treatment.

  11. Choindroitinase ABC I-mediated enhancement of oncolytic virus spread and anti tumor efficacy: a mathematical model.

    Science.gov (United States)

    Kim, Yangjin; Lee, Hyun Geun; Dmitrieva, Nina; Kim, Junseok; Kaur, Balveen; Friedman, Avner

    2014-01-01

    Oncolytic viruses are genetically engineered viruses that are designed to kill cancer cells while doing minimal damage to normal healthy tissue. After being injected into a tumor, they infect cancer cells, multiply inside them, and when a cancer cell is killed they move on to spread and infect other cancer cells. Chondroitinase ABC (Chase-ABC) is a bacterial enzyme that can remove a major glioma ECM component, chondroitin sulfate glycosoamino glycans from proteoglycans without any deleterious effects in vivo. It has been shown that Chase-ABC treatment is able to promote the spread of the viruses, increasing the efficacy of the viral treatment. In this paper we develop a mathematical model to investigate the effect of the Chase-ABC on the treatment of glioma by oncolytic viruses (OV). We show that the model's predictions agree with experimental results for a spherical glioma. We then use the model to test various treatment options in the heterogeneous microenvironment of the brain. The model predicts that separate injections of OV, one into the center of the tumor and another outside the tumor will result in better outcome than if the total injection is outside the tumor. In particular, the injection of the ECM-degrading enzyme (Chase-ABC) on the periphery of the main tumor core need to be administered in an optimal strategy in order to infect and eradicate the infiltrating glioma cells outside the tumor core in addition to proliferative cells in the bulk of tumor core. The model also predicts that the size of tumor satellites and distance between the primary tumor and multifocal/satellite lesions may be an important factor for the efficacy of the viral therapy with Chase treatment. PMID:25047810

  12. 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

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

    International Nuclear Information System (INIS)

    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. 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. 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. These data suggest MV-NIS plus radioiodine may be a potentially useful therapy for the treatment of medulloblastoma

  14. Oncolytic Effect of Newcastle Disease Virus AF2240 Strain on the MCF-7 Breast Cancer Cell Line

    Directory of Open Access Journals (Sweden)

    Fauziah Othman

    2010-01-01

    Full Text Available Objective: This study was carried out to investigate the oncolytic effect of the Newcastledisease virus (NDV strain AF2240 on the MCF-7 breast cancer cell line.Materials and Methods: The NDV-AF2240 was propagated in 11 days old embryonatedchicken eggs for 72 hours. The virus in the allantoic fluid was harvested andpurified. The haemagglutination (HA test was conducted on the purified virus to determinethe virus titre which was 16384 haemagglutination units (HAUs. The microculturetetrazolium assay (MTA was carried out via two methods-the monolayer and co-culturetechniques- to determine the inhibitory concentration (IC50 of NDV-AF2240 against theMCF-7 breast cancer cell line. Confocal laser scanning microscopy was carried out onpolyclonal chicken antibody and fluorescein isothiocynate (FITC conjugated goat antichickenantibody to observe virus localization in the cells. The terminal deoxynucleotidyltransferase-mediated dUTP nick end-labeling (TUNEL assay was conducted to quantifythe percentage of apoptotic cells.Results: IC50 value of NDV-AF2240 was two HAUs in both the monolayer and co-cultures.Virus particles were detected in the cytoplasm of MCF-7 breast cancer cell lineafter 24 and 48 hours post treatment. Virus budding was detected 72 hours post treatment.The number of apoptotic cells was significantly increased (p<0.05 72 hours postNDV-AF2240 treatment.Conclusion: The findings of this study show that NDV-AF2240 has an oncolytic effectagainst the MCF-7 breast cancer cell line. Further studies are needed to understand theanti cancer mechanism of this virus.

  15. Recombination in ionized gases

    International Nuclear Information System (INIS)

    In this paper it is shown how capture-stabilized methodology (both macroscopic and microscopic) can provide a generic basis for a unified treatment of all of the above recombination mechanisms. A new semiclassical theory of dissociative recombination is also presented in an effort to gain further insight into the physics not included in the first-order treatment and difficult to extract from numerical quantal treatments based on configuration mixing and on multichannel quantum defect theory. A simple analytical expression more accurate than the standard first-order result is obtained for the cross section σ and rate coefficient α. (author)

  16. Pre-existing Immunity and Passive Immunity to Adenovirus 5 Prevents Toxicity Caused by an Oncolytic Adenovirus Vector in the Syrian Hamster Model

    OpenAIRE

    Dhar, Debanjan; Spencer, Jacqueline F.; Toth, Karoly; Wold, William SM

    2009-01-01

    We have used Syrian hamsters to examine the role of pre-existing immunity to adenovirus (Ad) 5 in the toxicity of the oncolytic Ad vector INGN 007. Groups of hamsters were or were not immunized with Ad5. Half the hamsters were immunosuppressed using cyclophosphamide (CP), then injected intravenously (i.v.) with 3× the maximum tolerated dose (MTD) of INGN 007 (in immunocompetent hamsters), and toxicity and vector replication in the liver were quantitated. In nonimmunized immunocompetent hamste...

  17. Adapted ECHO-7 virus Rigvir immunotherapy (oncolytic virotherapy) prolongs survival in melanoma patients after surgical excision of the tumour in a retrospective study

    OpenAIRE

    Doniņa, Simona; Strēle, Ieva; Proboka, Guna; Auziņš, Jurgis; Alberts, Pēteris; Jonsson, Björn; Venskus, Dite; Muceniece, Aina

    2015-01-01

    An oncolytic, nonpathogenic ECHO-7 virus adapted for melanoma that has not been genetically modified (Rigvir) is approved and registered for virotherapy, an active and specific immunotherapy, in Latvia since 2004. The present retrospective study was carried out to determine the effectiveness of Rigvir in substage IB, IIA, IIB and IIC melanoma patients on time to progression and overall survival. White patients (N=79) who had undergone surgical excision of the primary melanoma tumour were incl...

  18. 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

  19. Downhole pressure attenuation apparatus

    International Nuclear Information System (INIS)

    This patent describes a process for preventing damage to tool strings and other downhole equipment in a well caused by pressures produced during detonation of one or more downhole explosive devices. It comprises adding to a tool string at least one pressure attenuating apparatus for attenuating the peak pressure wave and quasi-static pressure pulse produced by the explosive devices, the pressure attenuating apparatus including an initially closed relief vent including tubing means supporting a plurality of charge port assemblies each including an explosive filled shaped charge and a prestressed disc, the shaped charges interconnected by a detonating cord, the amount of explosive in each shaped charge being sufficient to rupture its associated disc without damaging surrounding tubular bodies in the well, and a vent chamber defined by the tubing means and providing a liquid free volume, and opening the relief vent substantially contemporaneously with downhole explosive device detonation by detonating the shaped charges to rupture the discs of the charge port assemblies

  20. Control algorithms for dynamic attenuators

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, Scott S., E-mail: sshsieh@stanford.edu [Department of Radiology, Stanford University, Stanford, California 94305 and Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Pelc, Norbert J. [Department of Radiology, Stanford University, Stanford California 94305 and Department of Bioengineering, Stanford University, Stanford, California 94305 (United States)

    2014-06-15

    Purpose: The authors describe algorithms to control dynamic attenuators in CT and compare their performance using simulated scans. Dynamic attenuators are prepatient beam shaping filters that modulate the distribution of x-ray fluence incident on the patient on a view-by-view basis. These attenuators can reduce dose while improving key image quality metrics such as peak or mean variance. In each view, the attenuator presents several degrees of freedom which may be individually adjusted. The total number of degrees of freedom across all views is very large, making many optimization techniques impractical. The authors develop a theory for optimally controlling these attenuators. Special attention is paid to a theoretically perfect attenuator which controls the fluence for each ray individually, but the authors also investigate and compare three other, practical attenuator designs which have been previously proposed: the piecewise-linear attenuator, the translating attenuator, and the double wedge attenuator. Methods: The authors pose and solve the optimization problems of minimizing the mean and peak variance subject to a fixed dose limit. For a perfect attenuator and mean variance minimization, this problem can be solved in simple, closed form. For other attenuator designs, the problem can be decomposed into separate problems for each view to greatly reduce the computational complexity. Peak variance minimization can be approximately solved using iterated, weighted mean variance (WMV) minimization. Also, the authors develop heuristics for the perfect and piecewise-linear attenuators which do not requirea priori knowledge of the patient anatomy. The authors compare these control algorithms on different types of dynamic attenuators using simulated raw data from forward projected DICOM files of a thorax and an abdomen. Results: The translating and double wedge attenuators reduce dose by an average of 30% relative to current techniques (bowtie filter with tube current

  1. Flexible graphene based microwave attenuators.

    Science.gov (United States)

    Byun, Kisik; Ju Park, Yong; Ahn, Jong-Hyun; Min, Byung-Wook

    2015-02-01

    We demonstrate flexible 3 dB and 6 dB microwave attenuators using multilayer graphene grown by the chemical vapor deposition method. On the basis of the characterized results of multilayer graphene and graphene-Au ohmic contacts, the graphene attenuators are designed and measured. The flexible graphene-based attenuators have 3 dB and 6 dB attenuation with a return loss of less than -15 dB at higher than 5 GHz. The devices have shown durability in a bending cycling test of 100 times. The circuit model of the attenuator based on the characterized results matches the experimental results well. PMID:25590144

  2. Flexible graphene based microwave attenuators

    International Nuclear Information System (INIS)

    We demonstrate flexible 3 dB and 6 dB microwave attenuators using multilayer graphene grown by the chemical vapor deposition method. On the basis of the characterized results of multilayer graphene and graphene–Au ohmic contacts, the graphene attenuators are designed and measured. The flexible graphene-based attenuators have 3 dB and 6 dB attenuation with a return loss of less than −15 dB at higher than 5 GHz. The devices have shown durability in a bending cycling test of 100 times. The circuit model of the attenuator based on the characterized results matches the experimental results well. (paper)

  3. Therapeutic efficacy of an oncolytic adenovirus containing RGD ligand in minor capsid protein IX and Fiber, Δ24DoubleRGD, in an ovarian cancer model

    Directory of Open Access Journals (Sweden)

    Anton V Borovjagin

    2012-02-01

    Full Text Available Ovarian cancer is the leading cause of gynecological disease death despite advances in medicine. Therefore, novel strategies are required for ovarian cancer therapy. Conditionally replicative adenoviruses (CRAds, genetically modified as anti-cancer therapeutics, are one of the most attractive candidate agents for cancer therapy. However, a paucity of coxsackie B virus and adenovirus receptor (CAR expression on the surface of ovarian cancer cells has impeded treatment of ovarian cancer using this approach.This study sought to engineer a CRAd with enhanced oncolytic ability in ovarian cancer cells, “Δ24DoubleRGD.” Δ24DoubleRGD carries an arginine-glycine-aspartate (RGD motif incorporated into both fiber and capsid protein IX (pIX and its oncolytic efficacy was evaluated in ovarian cancer. In vitro analysis of cell viability showed that infection of ovarian cancer cells with Δ24DoubleRGD leads to increased cell killing relative to the control CRAds. Data from this study suggested that not only an increase in number of RGD motifs on the CRAd capsid, but also a change in the repertoir of targeted integrins could lead to enhanced oncolytic potency of Δ24DoubleRGD in ovarian cancer cells in vitro. In an intraperitoneal model of ovarian cancer, mice injected with Δ24DoubleRGD showed, however, a similar survival rate as mice treated with control CRAds.

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

    International Nuclear Information System (INIS)

    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

  5. 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.

  6. 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…

  7. Recombineering Pseudomonas syringae

    Science.gov (United States)

    Here we report the identification of functions that promote genomic recombination of linear DNA introduced into Pseudomonas cells by electroporation. The genes encoding these functions were identified in Pseudomonas syringae pv. syringae B728a based on similarity to the lambda Red Exo/Beta and RecE...

  8. Recombinant rabies virus expressing dog GM-CSF is an efficacious oral rabies vaccine for dogs

    OpenAIRE

    Zhou, Ming; Wang, Lei; Zhou, Songqin; Wang, Zhao; Ruan, Juncheng; Tang, Lijun; Jia, Ziming; Cui, Min; Zhao, Ling; Fu, Zhen F.

    2015-01-01

    Developing efficacious oral rabies vaccines is an important step to increase immunization coverage for stray dogs, which are not accessible for parenteral vaccination. Our previous studies have demonstrated that recombinant rabies virus (RABV) expressing cytokines/chemokines induces robust protective immune responses after oral immunization in mice by recruiting and activating dendritic cells (DCs) and B cells. To develop an effective oral rabies vaccine for dogs, a recombinant attenuated RAB...

  9. Armoring CRAds with p21/Waf-1 shRNAs: the next generation of oncolytic adenoviruses

    OpenAIRE

    Höti, N; Chowdhury, WH; Mustafa, S.; Ribas, J; Castanares, M; Johnson, T.; Liu, M.; Lupold, SE; Rodriguez, R.

    2010-01-01

    Conditionally replicating adenoviruses (CRAds) represent a promising modality for the treatment of neoplastic diseases, including Prostate Cancer. Selectively replicating viruses can be generated by placing a tissue or cancer-specific promoter upstream of one or more of the viral genes required for replication (for example, E1A, E1B). We have previously reported multiple cellular processes that can attenuate viral replication, which in turn compromises viral oncolysis and tumor kill. In this ...

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

    International Nuclear Information System (INIS)

    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. 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 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 essential role of IFN in restricting infection was further

  11. 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

  12. Model-based design of growth-attenuated viruses.

    Directory of Open Access Journals (Sweden)

    Kwang-Il Lim

    2006-09-01

    Full Text Available Live-virus vaccines activate both humoral and cell-mediated immunity, require only a single boosting, and generally provide longer immune protection than killed or subunit vaccines. However, growth of live-virus vaccines must be attenuated to minimize their potential pathogenic effects, and mechanisms of attenuation by conventional serial-transfer viral adaptation are not well-understood. New methods of attenuation based on rational engineering of viral genomes may offer a potentially greater control if one can link defined genetic modifications to changes in virus growth. To begin to establish such links between genotype and growth phenotype, we developed a computer model for the intracellular growth of vesicular stomatitis virus (VSV, a well-studied, nonsegmented, negative-stranded RNA virus. Our model incorporated established regulatory mechanisms of VSV while integrating key wild-type infection steps: hijacking of host resources, transcription, translation, and replication, followed by assembly and release of progeny VSV particles. Generalization of the wild-type model to allow for genome rearrangements matched the experimentally observed attenuation ranking for recombinant VSV strains that altered the genome position of their nucleocapsid gene. Finally, our simulations captured previously reported experimental results showing how altering the positions of other VSV genes has the potential to attenuate the VSV growth while overexpressing the immunogenic VSV surface glycoprotein. Such models will facilitate the engineering of new live-virus vaccines by linking genomic manipulations to controlled changes in virus gene-expression and growth.

  13. Recombinant influenza vaccines.

    Science.gov (United States)

    Sedova, E S; Shcherbinin, D N; Migunov, A I; Smirnov, Iu A; Logunov, D Iu; Shmarov, M M; Tsybalova, L M; Naroditskiĭ, B S; Kiselev, O I; Gintsburg, A L

    2012-10-01

    This review covers the problems encountered in the construction and production of new recombinant influenza vaccines. New approaches to the development of influenza vaccines are investigated; they include reverse genetics methods, production of virus-like particles, and DNA- and viral vector-based vaccines. Such approaches as the delivery of foreign genes by DNA- and viral vector-based vaccines can preserve the native structure of antigens. Adenoviral vectors are a promising gene-delivery platform for a variety of genetic vaccines. Adenoviruses can efficiently penetrate the human organism through mucosal epithelium, thus providing long-term antigen persistence and induction of the innate immune response. This review provides an overview of the practicability of the production of new recombinant influenza cross-protective vaccines on the basis of adenoviral vectors expressing hemagglutinin genes of different influenza strains. PMID:23346377

  14. RECOMBINANT INFLUENZA VACCINES

    OpenAIRE

    Sedova, E.; Shcherbinin, D.; Migunov, A.; Smirnov, Iu; Logunov, D.; Shmarov, M.; Tsybalova, L.; Naroditskiĭ, B.; O. Kiselev; Gintsburg, A.

    2012-01-01

    This review covers the problems encountered in the construction and production of new recombinant influenza vaccines. New approaches to the development of influenza vaccines are investigated; they include reverse genetics methods, production of virus-like particles, and DNA- and viral vector-based vaccines. Such approaches as the delivery of foreign genes by DNA- and viral vector-based vaccines can preserve the native structure of antigens. Adenoviral vectors are a promising gene-delivery pla...

  15. Soluble recombinant influenza vaccines.

    OpenAIRE

    Fiers, W; Neirynck, S; Deroo, T; Saelens, X; Jou, W M

    2001-01-01

    Soluble, recombinant forms of influenza A virus haemagglutinin and neuraminidase have been produced in cells of lower eukaryotes, and shown in a mouse model to induce complete protective immunity against a lethal virus challenge. Soluble neuraminidase, produced in a baculovirus system, consisted of tetramers, dimers and monomers. Only the tetramers were enzymatically active. The immunogenicity decreased very considerably in the order tetra > di > mono. Therefore, we fused the head part of the...

  16. Nonradiative recombination in semiconductors

    CERN Document Server

    Abakumov, VN; Yassievich, IN

    1991-01-01

    In recent years, great progress has been made in the understandingof recombination processes controlling the number of excessfree carriers in semiconductors under nonequilibrium conditions. As a result, it is now possible to give a comprehensivetheoretical description of these processes. The authors haveselected a number of experimental results which elucidate theunderlying physical problems and enable a test of theoreticalmodels. The following topics are dealt with: phenomenological theory ofrecombination, theoretical models of shallow and deep localizedstates, cascade model of carrier captu

  17. Ultrasonic Attenuation in Zircaloy-4

    International Nuclear Information System (INIS)

    In this work the relationship between Zircaloy-4 grain size and ultrasonic attenuation behavior was studied for longitudinal waves in the frequency range of 10-90 MHz. The attenuation was analyzed as a function of frequency for samples with different mechanical and heat treatments having recrystallized and Widmanstatten structures with different grain size. The attenuation behavior was analyzed by different scattering models, depending on grain size, wavelength and frequency

  18. Chopping-Wheel Optical Attenuator

    Science.gov (United States)

    Leviton, Douglas B.

    1988-01-01

    Star-shaped rotating chopping wheel provides adjustable time-averaged attenuation of narrow beam of light without changing length of optical path or spectral distribution of light. Duty cycle or attenuation factor of chopped beam controlled by adjusting radius at which beam intersects wheel. Attenuation factor independent of wavelength. Useful in systems in which chopping frequency above frequency-response limits of photodetectors receiving chopped light. Used in systems using synchronous detection with lock-in amplifiers.

  19. 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

  20. Activation of the human immune system by chemotherapeutic or targeted agents combined with the oncolytic parvovirus H-1

    International Nuclear Information System (INIS)

    Parvovirus H-1 (H-1PV) infects and lyses human tumor cells including melanoma, hepatoma, gastric, colorectal, cervix and pancreatic cancers. We assessed whether the beneficial effects of chemotherapeutic agents or targeted agents could be combined with the oncolytic and immunostimmulatory properties of H-1PV. Using human ex vivo models we evaluated the biological and immunological effects of H-1PV-induced tumor cell lysis alone or in combination with chemotherapeutic or targeted agents in human melanoma cells +/- characterized human cytotoxic T-cells (CTL) and HLA-A2-restricted dendritic cells (DC). H-1PV-infected MZ7-Mel cells showed a clear reduction in cell viability of >50%, which appeared to occur primarily through apoptosis. This correlated with viral NS1 expression levels and was enhanced by combination with chemotherapeutic agents or sunitinib. Tumor cell preparations were phagocytosed by DC whose maturation was measured according to the treatment administered. Immature DC incubated with H-1PV-induced MZ7-Mel lysates significantly increased DC maturation compared with non-infected or necrotic MZ7-Mel cells. Tumor necrosis factor-α and interleukin-6 release was clearly increased by DC incubated with H-1PV-induced SK29-Mel tumor cell lysates (TCL) and was also high with DC-CTL co-cultures incubated with H-1PV-induced TCL. Similarly, DC co-cultures with TCL incubated with H-1PV combined with cytotoxic agents or sunitinib enhanced DC maturation to a greater extent than cytotoxic agents or sunitinib alone. Again, these combinations increased pro-inflammatory responses in DC-CTL co-cultures compared with chemotherapy or sunitinib alone. In our human models, chemotherapeutic or targeted agents did not only interfere with the pronounced immunomodulatory properties of H-1PV, but also reinforced drug-induced tumor cell killing. H-1PV combined with cisplatin, vincristine or sunitinib induced effective immunostimulation via a pronounced DC maturation, better cytokine

  1. 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 < 0.0001). 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

  2. Synergistic antitumor activity of oncolytic reovirus and chemotherapeutic agents in non-small cell lung cancer cells

    Directory of Open Access Journals (Sweden)

    Coffey Matthew C

    2009-07-01

    Full Text Available Abstract Background Reovirus type 3 Dearing strain (ReoT3D has an inherent propensity to preferentially infect and destroy cancer cells. The oncolytic activity of ReoT3D as a single agent has been demonstrated in vitro and in vivo against various cancers, including colon, pancreatic, ovarian and breast cancers. Its human safety and potential efficacy are currently being investigated in early clinical trials. In this study, we investigated the in vitro combination effects of ReoT3D and chemotherapeutic agents against human non-small cell lung cancer (NSCLC. Results ReoT3D alone exerted significant cytolytic activity in 7 of 9 NSCLC cell lines examined, with the 50% effective dose, defined as the initial virus dose to achieve 50% cell killing after 48 hours of infection, ranging from 1.46 ± 0.12 ~2.68 ± 0.25 (mean ± SD log10 pfu/cell. Chou-Talalay analysis of the combination of ReoT3D with cisplatin, gemcitabine, or vinblastine demonstrated strong synergistic effects on cell killing, but only in cell lines that were sensitive to these compounds. In contrast, the combination of ReoT3D and paclitaxel was invariably synergistic in all cell lines tested, regardless of their levels of sensitivity to either agent. Treatment of NSCLC cell lines with the ReoT3D-paclitaxel combination resulted in increased poly (ADP-ribose polymerase cleavage and caspase activity compared to single therapy, indicating enhanced apoptosis induction in dually treated NSCLC cells. NSCLC cells treated with the ReoT3D-paclitaxel combination showed increased proportions of mitotic and apoptotic cells, and a more pronounced level of caspase-3 activation was demonstrated in mitotically arrested cells. Conclusion These data suggest that the oncolytic activity of ReoT3D can be potentiated by taxanes and other chemotherapeutic agents, and that the ReoT3D-taxane combination most effectively achieves synergy through accelerated apoptosis triggered by prolonged mitotic arrest.

  3. LINE-ABOVE-GROUND ATTENUATOR

    Science.gov (United States)

    Wilds, R.B.; Ames, J.R.

    1957-09-24

    The line-above-ground attenuator provides a continuously variable microwave attenuator for a coaxial line that is capable of high attenuation and low insertion loss. The device consists of a short section of the line-above- ground plane type transmission lime, a pair of identical rectangular slabs of lossy material like polytron, whose longitudinal axes are parallel to and indentically spaced away from either side of the line, and a geared mechanism to adjust amd maintain this spaced relationship. This device permits optimum fineness and accuracy of attenuator control which heretofore has been difficult to achieve.

  4. Fiber optic attenuator

    Science.gov (United States)

    Buzzetti, Mike F. (Inventor)

    1994-01-01

    A fiber optic attenuator of the invention is a mandrel structure through which a bundle of optical fibers is wrapped around in a complete circle. The mandrel structure includes a flexible cylindrical sheath through which the bundle passes. A set screw on the mandrel structure impacts one side of the sheath against two posts on the opposite side of the sheath. By rotating the screw, the sheath is deformed to extend partially between the two posts, bending the fiber optic bundle to a small radius controlled by rotating the set screw. Bending the fiber optic bundle to a small radius causes light in each optical fiber to be lost in the cladding, the amount depending upon the radius about which the bundle is bent.

  5. 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. PMID:26403370

  6. Recombinant Newcastle disease vaccines: risk for reversion to virulence and spread in non-target species

    Science.gov (United States)

    The present study is being conducted to determine the risk associated with using live recombinant NDV(rNDV) vaccines in the field. The goals of this study are to 1) determine the risk of rNDV vaccines, containing an attenuated fusion (F) protein cleavage site, to revert back to a virulent virus phen...

  7. 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.

  8. Primordial magnetogenesis before recombination

    CERN Document Server

    Fabre, Ophélia

    2015-01-01

    The origin of large magnetic fields in the Universe remains currently unknown. We investigate here a mechanism before recombination based on known physics. The source of the vorticity is due to the changes in the photon distribution function caused by the fluctuations in the background photons. We show that the magnetic field generated in the MHD limit, due to the Coulomb scattering, is of the order $10^{-49}$ G. We explicitly show that the magnetic fields generated from this process are sustainable and are not erased by resistive diffusion. We compare the results with current observations and discuss the implications.

  9. Adjustable Optical-Fiber Attenuator

    Science.gov (United States)

    Buzzetti, Mike F.

    1994-01-01

    Adjustable fiber-optic attenuator utilizes bending loss to reduce strength of light transmitted along it. Attenuator functions without introducing measurable back-reflection or insertion loss. Relatively insensitive to vibration and changes in temperature. Potential applications include cable television, telephone networks, other signal-distribution networks, and laboratory instrumentation.

  10. Recombinant Yellow Fever Vaccine Virus 17D Expressing Simian Immunodeficiency Virus SIVmac239 Gag Induces SIV-Specific CD8+ T-Cell Responses in Rhesus Macaques ▿

    OpenAIRE

    Bonaldo, Myrna C.; Martins, Mauricio A.; Rudersdorf, Richard; Mudd, Philip A.; Sacha, Jonah B.; Piaskowski, Shari M.; Costa Neves, Patrícia C.; Veloso de Santana, Marlon G.; Vojnov, Lara; Capuano, Saverio; Rakasz, Eva G.; Wilson, Nancy A.; Fulkerson, John; Sadoff, Jerald C.; Watkins, David I.

    2010-01-01

    Here we describe a novel vaccine vector for expressing human immunodeficiency virus (HIV) antigens. We show that recombinant attenuated yellow fever vaccine virus 17D expressing simian immunodeficiency virus SIVmac239 Gag sequences can be used as a vector to generate SIV-specific CD8+ T-cell responses in the rhesus macaque. Priming with recombinant BCG expressing SIV antigens increased the frequency of these SIV-specific CD8+ T-cell responses after recombinant YF17D boosting. These recombinan...

  11. 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. PMID:27119092

  12. SPECT/CT Imaging of hNIS -Expression after Intravenous Delivery of an Oncolytic Adenovirus and 131I

    Science.gov (United States)

    Hakkarainen, Tanja; Tenhunen, Mikko; Diaconu, Iulia; Kuhmonen, Venla; Kairemo, Kalevi; Kanerva, Anna; Airaksinen, Anu J.; Hemminki, Akseli

    2012-01-01

    Oncolytic adenoviruses can be engineered for better tumor selectivity, gene delivery and be armed for imaging and concentrating radionuclides into tumors for synergistic oncolysis. We constructed Ad5/3-hTERT-hNIS where replication is controlled by hTERT-promoter. Ad5/3-hTERT-hNIS expresses hNIS for imaging of transgene expression and for treatment of infected tumors by radioiodine. Ad5/3-hTERT-hNIS efficiently killed prostate cancer cells and induced iodine uptake in vitro and in vivo after intratumoral virus administration. Survival of mice treated with intravenous Ad5/3-hTERT-hNIS significantly prolonged survival over mock or radioiodine only but the combination of virus with radioiodine was not more effective than virus alone. Temporal and spatial changes in hNIS-expression during therapy were detected with SPECT, demonstrating feasibility of evaluation of the combination therapy with hNIS-expressing adenoviruses and radioiodide. PMID:22412937

  13. Mesenchymal Stromal Cells for Linked Delivery of Oncolytic and Apoptotic Adenoviruses to Non-small-cell Lung Cancers.

    Science.gov (United States)

    Hoyos, Valentina; Del Bufalo, Francesca; Yagyu, Shigeki; Ando, Miki; Dotti, Gianpietro; Suzuki, Masataka; Bouchier-Hayes, Lisa; Alemany, Ramon; Brenner, Malcolm K

    2015-09-01

    Oncolytic adenoviruses (OAdV) represent a promising strategy for cancer therapy. Despite their activity in preclinical models, to date the clinical efficacy remains confined to minor responses after intratumor injection. To overcome these limitations, we developed an alternative approach using the combination of the OAdv ICOVIR15 with a replication incompetent adenoviral vector carrying the suicide gene of inducible Caspase 9 (Ad.iC9), both of which are delivered by mesenchymal stromal cells (MSCs). We hypothesized that coinfection with ICOVIR15 and Ad.iC9 would allow MSCs to replicate both vectors and deliver two distinct types of antitumor therapy to the tumor, amplifying the cytotoxic effects of the two viruses, in a non-small-cell lung cancer (NSCLC) model. We showed that MSCs can replicate and release both vectors, enabling significant transduction of the iC9 gene in tumor cells. In the in vivo model using human NSCLC xenografts, MSCs homed to lung tumors where they released both viruses. The activation of iC9 by the chemical inducer of dimerization (CID) significantly enhanced the antitumor activity of the ICOVIR15, increasing the tumor control and translating into improved overall survival of tumor-bearing mice. These data support the use of this innovative approach for the treatment of NSCLC. PMID:26084970

  14. 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. PMID:27119092

  15. 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. PMID:24975392

  16. CRMAGE: CRISPR Optimized MAGE Recombineering

    OpenAIRE

    Carlotta Ronda; Lasse Ebdrup Pedersen; Sommer, Morten O. A.; Alex Toftgaard Nielsen

    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. Using CRMAGE, the recombineering efficiency was between 96.5% and 99.7% for gene recoding of three genomic targets, compared to between 0.68% and 5.4% using traditional recombineering. For modulat...

  17. The influence of the multi-basic cleavage site of the H5 hemagglutinin on the attenuation, immunogenicity and efficacy of a live attenuated influenza A h5N1 cold-adapted vaccine virus

    Science.gov (United States)

    A recombinant live attenuated influenza virus (LAIV) deltaH5N1 vaccine with a modified hemagglutinin (HA) and intact neuraminidase genes from A/Vietnam/1203/04 (H5N1) and the six remaining genome segments from A/Ann Arbor/6/60 (H2N2) cold-adapted (AA ca) virus was attenuated in chickens, mice and fe...

  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. Seismic attenuation in fractured media

    International Nuclear Information System (INIS)

    The prime objective of this paper is to quantitatively estimate seismic attenuation caused by fractures with different physical parameters. In seismic wave simulation, the fractured media are treated as the anisotropic media and fractures are represented by frequency-dependent elastic constants. Based on numerical experiments with three different parameters, namely viscosity, porosity and the Lamé parameters, this paper has the following observations. First, seismic attenuation is not affected by the viscosity within fractures, although it increases with the increase of porosity and decreases with the increase of the Lamé parameters within fractures. Among the latter two parameters, seismic attenuation is more sensitive to the Lamé parameters than to the porosity. Second, for the attenuation anisotropy, low frequencies have more anisotropic effect than high frequencies. For example, a 50 Hz wavefield has the strongest anisotropy effect if compared to 100 and 150 Hz wavefields. The attenuation anisotropy for low frequency (say 50 Hz) is more sensitive to the viscosity than the porosity and the Lamé parameters have the weakest effect among these three parameters. These observations suggest that low-frequency seismic attenuation, and especially the attenuation anisotropy in low frequency, would have great potential for fluid discrimination within fractured media. (paper)

  20. 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 as w...

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

    International Nuclear Information System (INIS)

    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. 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. 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. 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

  2. Heat shock protein 72 expression allows permissive replication of oncolytic adenovirus dl1520 (ONYX-015 in rat glioblastoma cells

    Directory of Open Access Journals (Sweden)

    Krewet James A

    2005-03-01

    Full Text Available Abstract In this study we have made novel observations with regards to potentiation of the tumoricidal activity of the oncolytic adenovirus, dl1520 (ONYX-015 in rat glioblastoma cell lines expressing heat shock protein 72 (HSP72 due to permissive virus replication. ONYX-015 is a conditionally replicating adenovirus that is deleted for the E1B 55 kDA gene product whose normal function is to interact with cell-cycle regulatory proteins to permit virus replication. However, many murine and rodent cell lines are not permissive for adenovirus replication. Previously, it has been reported that the heat shock response is necessary for adenovirus replication and that induction of heat shock proteins is mediated by E1 region gene products. Therefore, we hypothesized that HSP72 expression may allow for permissive replication of ONYX-015 in previously non-permissive cells. Rat glioma cell lines 9L and RT2 were transfected with a plasmids expressing HSP72 or GFP. After infection with ONYX-015, no tumoricidal activity is observed in GFP expressing cell lines despite adequate transduction. In contrast, HSP72 transfected cells show cytopathic effects by 72 hours and greater than 75% loss of viability by 96 hours. Burst assays show active virus replication in the HSP72 expressing cell lines. Therefore, 9L-HSP72 and RT2-HSP72 are ideal models to evaluate the efficacy of ONYX-015 in an immunocompetent rat model. Our study has implications for creating rodent tumor models for pre-clinical studies with E1 region deleted conditionally replicating adenovirus.

  3. Double-detargeted oncolytic adenovirus shows replication arrest in liver cells and retains neuroendocrine cell killing ability.

    Directory of Open Access Journals (Sweden)

    Justyna Leja

    Full Text Available BACKGROUND: We have previously developed an oncolytic serotype 5 adenovirus (Ad5 with chromogranin-A (CgA promoter-controlled E1A expression, Ad[CgA-E1A], with the intention to treat neuroendocrine tumors, including carcinoids. Since carcinoids tend to metastasize to the liver it is important to fully repress viral replication in hepatocytes to avoid adenovirus-related liver toxicity. Herein, we explore miRNA-based regulation of E1A expression as a complementary mechanism to promoter-based transcriptional control. METHODOLOGY/PRINCIPAL FINDINGS: Ad[CgA-E1A-miR122], where E1A expression is further controlled by six tandem repeats of the target sequence for the liver-specific miR122, was constructed and compared to Ad[CgA-E1A]. We observed E1A suppression and replication arrest of the miR122-detargeted adenovirus in normal hepatocytes, while the two viruses killed carcinoid cells to the same degree. Repeated intravenous injections of Ad[CgA-E1A] induced liver toxicity in mice while Ad[CgA-E1A-miR122] injections did not. Furthermore, a miR122-detargeted adenovirus with the wild-type E1A promoter showed reduced replication in hepatic cells compared to wild-type Ad5 but not to the same extent as the miR122-detargeted adenovirus with the neuroendocrine-selective CgA promoter. CONCLUSIONS/SIGNIFICANCE: A combination of transcriptional (promoter and post-transcriptional (miRNA target regulation to control virus replication may allow for the use of higher doses of adenovirus for efficient tumors treatment without liver toxicity.

  4. Potent anti-tumor effects of a dual specific oncolytic adenovirus expressing apoptin in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Encheng Yang

    2010-01-01

    Full Text Available Abstract Background Oncolytic virotherapy is an attractive drug platform of cancer gene therapy, but efficacy and specificity are important prerequisites for success of such strategies. Previous studies determined that Apoptin is a p53 independent, bcl-2 insensitive apoptotic protein with the ability to specifically induce apoptosis in tumor cells. Here, we generated a conditional replication-competent adenovirus (CRCA, designated Ad-hTERT-E1a-Apoptin, and investigated the effectiveness of the CRCA a gene therapy agent for further clinical trials. Results The observation that infection with Ad-hTERT-E1a-Apoptin significantly inhibited growth of the melanoma cells, protecting normal human epidermal melanocytes from growth inhibition confirmed cancer cell selective adenoviral replication, growth inhibition, and apoptosis induction of this therapeutic approach. The in vivo assays performed by using C57BL/6 mice containing established primary or metastatic tumors expanded the in vitro studies. When treated with Ad-hTERT-E1a-Apoptin, the subcutaneous primary tumor volume reduction was not only observed in intratumoral injection group but in systemic delivery mice. In the lung metastasis model, Ad-hTERT-E1a-Apoptin effectively suppressed pulmonary metastatic lesions. Furthermore, treatment of primary and metastatic models with Ad-hTERT-E1a-Apoptin increased mice survival. Conclusions These data further reinforce the previously research showing that an adenovirus expressing Apoptin is more effective and advocate the potential applications of Ad-hTERT-E1a-Apoptin in the treatment of neoplastic diseases in future clinical trials.

  5. Genome-wide lentiviral shRNA screen identifies serine/arginine-rich splicing factor 2 as a determinant of oncolytic virus activity in breast cancer cells.

    Science.gov (United States)

    Workenhe, S T; Ketela, T; Moffat, J; Cuddington, B P; Mossman, K L

    2016-05-12

    Oncolytic human herpes simplex virus type 1 (HSV-1) shows promising treatment efficacy in late-stage clinical trials. The anticancer activity of oncolytic viruses relies on deregulated pathways in cancer cells, which make them permissive to oncolysis. To identify pathways that restrict HSV-1 KM100-mediated oncolysis, this study used a pooled genome-wide short hairpin RNA library and found that depletion of the splicing factor arginine-rich splicing factor 2 (SRSF2) leads to enhanced cytotoxicity of breast cancer cells by KM100. Serine/arginine-rich (SR) proteins are a family of RNA-binding phosphoproteins that control both constitutive and alternative pre-mRNA splicing. Further characterization showed that KM100 infection of HS578T cells under conditions of low SRSF2 leads to pronounced apoptosis without a corresponding increase in virus replication. As DNA topoisomerase I inhibitors can limit the phosphorylation of SRSF2, we combined a topoisomerase I inhibitor chemotherapeutic with KM100 and observed synergistic anticancer effect in vitro and prolonged survival of tumor-bearing mice in vivo. PMID:26257065

  6. 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. PMID:25727013

  7. Delayed recombination and standard rulers

    International Nuclear Information System (INIS)

    Measurements of baryonic acoustic oscillations (BAOs) in galaxy surveys have been recognized as a powerful tool for constraining dark energy. However, this method relies on the knowledge of the size of the acoustic horizon at recombination derived from cosmic microwave background (CMB) anisotropy measurements. This estimate is typically derived assuming a standard recombination scheme; additional radiation sources can delay recombination altering the cosmic ionization history and the cosmological inferences drawn from CMB and BAO data. In this paper we quantify the effect of delayed recombination on the determination of dark energy parameters from future BAO surveys such as the Baryon Oscillation Spectroscopic Survey and the Wide-Field Multi-Object Spectrograph. We find the impact to be small but still not negligible. In particular, if recombination is nonstandard (to a level still allowed by CMB data), but this is ignored, future surveys may incorrectly suggest the presence of a redshift-dependent dark energy component. On the other hand, in the case of delayed recombination, adding to the analysis one extra parameter describing deviations from standard recombination does not significantly degrade the error bars on dark energy parameters and yields unbiased estimates. This is due to the CMB-BAO complementarity.

  8. Estimation of Water Vapour Attenuation And Rain Attenuation

    Directory of Open Access Journals (Sweden)

    K.Kalyana Srinivas

    2015-04-01

    Full Text Available Attenuation due to and water vapour and rain can severely degrade the radio wave propagation at centimeter or millimeter wavelengths. It restricts the path length of radio communication systems and limits the use of higher frequencies for line-of-sight microwave links and satellite communications. The attenuation will pose a greater problem to communication as the frequency of occurrence of heavy rain increases.In a tropical region, like Malaysia, where excessive rainfall is a common phenomenon throughout the year, the knowledge of the rain attenuation at the frequency of operation is extremely required for the design of a reliable terrestrial and earth space communication link at a particular location.

  9. The attenuation and the attenuators: strategies and tactics

    Directory of Open Access Journals (Sweden)

    Antonio Briz

    2013-12-01

    Full Text Available This work is inscribed in a research project (ES.POR.ATENUAÇÃO that seeks to analyze and explain the attenuator activity in different regional varieties of Spanish and Portuguese, in order to perform, subsequently, different contrastive intralinguistic and interlinguistic studies. In this article, we explain some of the theoretical and methodological principles on which are based the qualitative and quantitative analysis. And especially, we will refer to the concept of attenuation (Briz 1995, 2002, 2003, 2005, 2007a, 2012.

  10. 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.

  11. 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)

  12. Stable recombination hotspots in birds.

    Science.gov (United States)

    Singhal, Sonal; Leffler, Ellen M; Sannareddy, Keerthi; Turner, Isaac; Venn, Oliver; Hooper, Daniel M; Strand, Alva I; Li, Qiye; Raney, Brian; Balakrishnan, Christopher N; Griffith, Simon C; McVean, Gil; Przeworski, Molly

    2015-11-20

    The DNA-binding protein PRDM9 has a critical role in specifying meiotic recombination hotspots in mice and apes, but it appears to be absent from other vertebrate species, including birds. To study the evolution and determinants of recombination in species lacking the gene that encodes PRDM9, we inferred fine-scale genetic maps from population resequencing data for two bird species: the zebra finch, Taeniopygia guttata, and the long-tailed finch, Poephila acuticauda. We found that both species have recombination hotspots, which are enriched near functional genomic elements. Unlike in mice and apes, most hotspots are shared between the two species, and their conservation seems to extend over tens of millions of years. These observations suggest that in the absence of PRDM9, recombination targets functional features that both enable access to the genome and constrain its evolution. PMID:26586757

  13. Combinatorics in Recombinational Population Genomics

    Science.gov (United States)

    Parida, Laxmi

    The work that I will discuss is motivated by the need for understanding, and processing, the manifestations of recombination events in chromosome sequences. In this talk, we focus on two related problems. First, we explore the very general problem of reconstructability of pedigree history. How plausible is it to unravel the history of a complete unit (chromosome) of inheritance? The second problem deals with reconstructing the recombinational history of a collection of chromosomes.

  14. Progenitors of Recombining Supernova Remnants

    OpenAIRE

    Moriya, Takashi J.

    2012-01-01

    Usual supernova remnants have either ionizing plasma or plasma in collisional ionization equilibrium, i.e., the ionization temperature is lower than or equal to the electron temperature. However, the existence of recombining supernova remnants, i.e., supernova remnants with the ionization temperature higher than the electron temperature, is recently confirmed. One suggested way to have recombining plasma in a supernova remnant is to have a dense circumstellar medium at the time of the superno...

  15. Do mitochondria recombine in humans?

    OpenAIRE

    Eyre-Walker, A

    2000-01-01

    Until very recently, mitochondria were thought to be clonally inherited through the maternal line in most higher animals. However, three papers published in 2000 claimed population-genetic evidence of recombination in human mitochondrial DNA. Here I review the current state of the debate. I review the evidence for the two main pathways by which recombination might occur: through paternal leakage and via a mitochondrial DNA sequence in the nuclear genome. There is no strong evidence for either...

  16. Recombinant snake venom prothrombin activators

    OpenAIRE

    Lövgren, Ann

    2012-01-01

    Three prothrombin activators; ecarin, which was originally isolated from the venom of the saw-scaled viper Echis carinatus, trocarin from the rough-scaled snake Tropidechis carinatus, and oscutarin from the Taipan snake Oxyuranus scutellatus, were expressed in mammalian cells with the purpose to obtain recombinant prothrombin activators that could be used to convert prothrombin to thrombin. We have previously reported that recombinant ecarin can efficiently generate thrombin without the need ...

  17. Delayed recombination and cosmic parameters

    International Nuclear Information System (INIS)

    Current cosmological constraints from cosmic microwave background anisotropies are typically derived assuming a standard recombination scheme, however additional resonance and ionizing radiation sources can delay recombination, altering the cosmic ionization history and the cosmological inferences drawn from the cosmic microwave background data. We show that for recent observations of the cosmic microwave background anisotropy, from the Wilkinson microwave anisotropy probe satellite mission (WMAP) 5-year survey and from the arcminute cosmology bolometer array receiver experiment, additional resonance radiation is nearly degenerate with variations in the spectral index, ns, and has a marked effect on uncertainties in constraints on the Hubble constant, age of the universe, curvature and the upper bound on the neutrino mass. When a modified recombination scheme is considered, the redshift of recombination is constrained to z*=1078±11, with uncertainties in the measurement weaker by 1 order of magnitude than those obtained under the assumption of standard recombination while constraints on the shift parameter are shifted by 1σ to R=1.734±0.028. From the WMAP5 data we obtain the following constraints on the resonance and ionization sources parameters: εαi<0.058 at 95% c.l.. Although delayed recombination limits the precision of parameter estimation from the WMAP satellite, we demonstrate that this should not be the case for future, smaller angular scales measurements, such as those by the Planck satellite mission.

  18. Sound attenuation in magnetorheological fluids

    Science.gov (United States)

    Rodríguez-López, J.; Elvira, L.; Resa, P.; Montero de Espinosa, F.

    2013-02-01

    In this work, the attenuation of ultrasonic elastic waves propagating through magnetorheological (MR) fluids is analysed as a function of the particle volume fraction and the magnetic field intensity. Non-commercial MR fluids made with iron ferromagnetic particles and two different solvents (an olive oil based solution and an Araldite-epoxy) were used. Particle volume fractions of up to 0.25 were analysed. It is shown that the attenuation of sound depends strongly on the solvent used and the volume fraction. The influence of a magnetic field up to 212 mT was studied and it was found that the sound attenuation increases with the magnetic intensity until saturation is reached. A hysteretic effect is evident once the magnetic field is removed.

  19. The effect of a single recombination event

    DEFF Research Database (Denmark)

    Schierup, Mikkel Heide; Jensen, Thomas Mailund; Wiuf, Carsten

    the effect of a recombination event is the genealogical type of the event and whether SNP variation is present that can reveal the genealogical consequences of the recombination event. Recombination events that only change some branch lengths in the genealogy have a very small, but detectable, effect....... The more lineages left when the recombination event occurs, the larger effect it has, implying that it is mainly young recombination events that we detect when estimating the rate. If the population is growing, though, more lineages are present back in time and relatively more ancient recombination...... shared by these two populations are expected to contribute compared to the effect of private recombination events...

  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. Live attenuated measles virus vaccine therapy for locally established malignant glioblastoma tumor cells

    Directory of Open Access Journals (Sweden)

    Al-Shammari AM

    2014-05-01

    , and 120 hours of infection compared with control cells. This study concludes that live attenuated MV Schwarz vaccine induces the oncolytic effect in Iraqi tumor cell line ANGM5 and in the rhabdomyosarcoma cell line through syncytia in tumor cells, which is one of the causes of cell death. The MV vaccine strain has the ability to insert its hemagglutinin protein into the tumor cell surface, leading to modification of the antigenic surface of tumor cells that may induce an antitumor immune response, MV vaccine strain induced cell killing by direct cytolysis and apoptosis induction. These antitumor features may indicate the use of MV in the treatment of glioblastoma.Keywords: virotherapy, glioblastoma multiforme

  2. Investigations for designing catalytic recombiners

    International Nuclear Information System (INIS)

    In case of a severe accident in pressurised water reactors (PWR) a high amount of hydrogen up to about 20,000 m3 might be generated and released into the containments. The mixture consisting of hydrogen and oxygen may either burn or detonate, if ignited. In case of detonation the generated shock wave may endanger the components of the plant or the plant itself. Consequently, effective removal of hydrogen is required. The fact that hydrogen and oxygen react exo-thermally on catalytically acting surfaces already at low temperatures generating steam and heat is made use of in catalytic recombiners. They consist of substrates coated with catalyst (mainly platinum or palladium) which are arranged inside a casing. Being passively acting measures, recombiners do not need any additional energy supply. Experimental investigations on catalytic hydrogen recombination are conducted at FZJ (Forschungszentrum Juelich) using three test facilities. The results yield insight in the development potential of contemporary recombiner systems as well as of innovative systems. Detailed investigations on a recombiner section show strong temperature gradients over the surface of a catalytically coated sample. Dependent on the flow velocity, ignition temperature may be reached at the leading edge already at an inlet hydrogen concentration of about 5 vol.-%. The thermal strain of the substrate leads to considerable detachment of catalyst particles probably causing unintended ignition of the flammable mixture. Temperature peaks can be prevented effectively by leaving the first part of the plate uncoated. In order to avoid overheating of the catalyst elements of a recombiner even at high hydrogen concentrations a modular system of porous substrates is proposed. The metallic substrates are coated with platinum at low catalyst densities thus limiting the activity of the single specimen. A modular arrangement of these elements provides high recombination rates over a large hydrogen concentration

  3. Homologous Recombination in Negative Sense RNA Viruses

    OpenAIRE

    Michael Worobey; Guan-Zhu Han

    2011-01-01

    Recombination is an important process that influences biological evolution at many different levels. More and more homologous recombination events have been reported among negative sense RNA viruses recently. While sporadic authentic examples indicate that homologous recombination does occur, recombination seems to be generally rare or even absent in most negative sense RNA viruses, and most of the homologous recombination events reported in the literature were likely generated artificially d...

  4. Recombining WMAP: Constraints on ionizing and resonance radiation at recombination

    International Nuclear Information System (INIS)

    We place new constraints on sources of ionizing and resonance radiation at the epoch of the recombination process using the recent cosmic microwave background temperature and polarization spectra coming from the Wilkinson Microwave Anisotropy Probe (WMAP). We find that non-standard recombination scenarios are still consistent with the current data. In light of this we study the impact that such models can have on the determination of several cosmological parameters. In particular, the constraints on curvature and baryon density appear to be weakly affected by a modified recombination scheme. However, it may affect the current WMAP constraints on inflationary parameters such as the spectral index ns and its running. Physically motivated models, such as those based on primordial black holes or super heavy dark matter decay, are able to provide a good fit to the current data. Future observations in both temperature and polarization will be needed to more stringently test these models

  5. 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 biased...

  6. 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...

  7. Attenuation of Vrancea events revisited

    International Nuclear Information System (INIS)

    New aspects of the frequency-dependent attenuation of the seismic waves traveling from Vrancea subcrustal sources toward NW (Transylvanian Basin) and SE (Romanian Plain) are evidenced by the recent experimental data made available by the CALIXTO'99 tomography experiment. The observations validate the previous theoretical computations performed for the assessment, by means of a deterministic approach, of the seismic hazard in Romania. They reveal an essential aspect of the seismic ground motion attenuation, that has important implications on the probabilistic assessment of seismic hazard from Vrancea intermediate-depth earthquakes. The attenuation toward NW is shown to be a much stronger frequency-dependent effect than the attenuation toward SE and the seismic hazard computed by the deterministic approach fits satisfactorily well the observed ground motion distribution in the low-frequency band (< 1 Hz). The apparent contradiction with the historically-based intensity maps arises mainly from a systematic difference in the vulnerability (buildings eigenperiod) of the buildings in the intra- and extra-Carpathians regions. (author)

  8. Rational plasmid design and bioprocess optimization to enhance recombinant adeno-associated virus (AAV) productivity in mammalian cells.

    Science.gov (United States)

    Emmerling, Verena V; Pegel, Antje; Milian, Ernest G; Venereo-Sanchez, Alina; Kunz, Marion; Wegele, Jessica; Kamen, Amine A; Kochanek, Stefan; Hoerer, Markus

    2016-02-01

    Viral vectors used for gene and oncolytic therapy belong to the most promising biological products for future therapeutics. Clinical success of recombinant adeno-associated virus (rAAV) based therapies raises considerable demand for viral vectors, which cannot be met by current manufacturing strategies. Addressing existing bottlenecks, we improved a plasmid system termed rep/cap split packaging and designed a minimal plasmid encoding adenoviral helper function. Plasmid modifications led to a 12-fold increase in rAAV vector titers compared to the widely used pDG standard system. Evaluation of different production approaches revealed superiority of processes based on anchorage- and serum-dependent HEK293T cells, exhibiting about 15-fold higher specific and volumetric productivity compared to well-established suspension cells cultivated in serum-free medium. As for most other viral vectors, classical stirred-tank bioreactor production is thus still not capable of providing drug product of sufficient amount. We show that manufacturing strategies employing classical surface-providing culture systems can be successfully transferred to the new fully-controlled, single-use bioreactor system Integrity(TM) iCELLis(TM) . In summary, we demonstrate substantial bioprocess optimizations leading to more efficient and scalable production processes suggesting a promising way for flexible large-scale rAAV manufacturing. PMID:26284700

  9. 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.

  10. Recombinant vaccines and the development of new vaccine strategies

    International Nuclear Information System (INIS)

    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

  11. 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.

  12. 3D modeling of human cancer: A PEG-fibrin hydrogel system to study the role of tumor microenvironment and recapitulate the in vivo effect of oncolytic adenovirus.

    Science.gov (United States)

    Del Bufalo, Francesca; Manzo, Teresa; Hoyos, Valentina; Yagyu, Shigeki; Caruana, Ignazio; Jacot, Jeffrey; Benavides, Omar; Rosen, Daniel; Brenner, Malcolm K

    2016-04-01

    Interactions between malignant and stromal cells and the 3D spatial architecture of the tumor both substantially modify tumor behavior, including the responses to small molecule drugs and biological therapies. Conventional 2D culture systems cannot replicate this complexity. To overcome these limitations and more accurately model solid tumors, we developed a highly versatile 3D PEG-fibrin hydrogel model of human lung adenocarcinoma. Our model relevantly recapitulates the effect of oncolytic adenovirus; tumor responses in this setting nearly reproduce those observed in vivo. We have also validated the use of this model for complex, long-term, 3D cultures of cancer cells and their stroma (fibroblasts and endothelial cells). Both tumor proliferation and invasiveness were enhanced in the presence of stromal components. These results validate our 3D hydrogel model as a relevant platform to study cancer biology and tumor responses to biological treatments. PMID:26826297

  13. Inhomogeneous recombinations during cosmic reionization

    CERN Document Server

    Sobacchi, Emanuele

    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 feedback on star-formation, we present large-scale, semi-numeric reionization simulations which self-consistently track the local (sub-grid) evolution of both sources and sinks of ionizing photons. Our simple, single-parameter model naturally results in both an extended reionization and a modest, slowly-evolving emissivity, consistent with observations. Recombinations are instrumental in slowing the growth of large HII regions, and damping the rapid rise of the ionizing background in the late stages of (and following) reioniza...

  14. Recombinant snake venom prothrombin activators.

    Science.gov (United States)

    Lövgren, Ann

    2013-01-01

    Three prothrombin activators; ecarin, which was originally isolated from the venom of the saw-scaled viper Echis carinatus, trocarin from the rough-scaled snake Tropidechis carinatus, and oscutarin from the Taipan snake Oxyuranus scutellatus, were expressed in mammalian cells with the purpose to obtain recombinant prothrombin activators that could be used to convert prothrombin to thrombin. We have previously reported that recombinant ecarin can efficiently generate thrombin without the need for additional cofactors, but does not discriminate non-carboxylated prothrombin from biologically active γ-carboxylated prothrombin. Here we report that recombinant trocarin and oscutarin could not efficiently generate thrombin without additional protein co-factors. We confirm that both trocarin and oscutarin are similar to human coagulation Factor X (FX), explaining the need for additional cofactors. Sequencing of a genomic fragment containing 7 out of the 8 exons coding for oscutarin further confirmed the similarity to human FX. PMID:23111318

  15. An oncolytic adenovirus enhances antiangiogenic and antitumoral effects of a replication-deficient adenovirus encoding endostatin by rescuing its selective replication in nasopharyngeal carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ran-yi, E-mail: liuranyi@mail.sysu.edu.cn [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Guangzhou 510060 (China); Zhou, Ling [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Guangzhou 510060 (China); Zhang, Yan-ling [School of Biotechnology, Southern Medical University, Guangzhou 510515 (China); Huang, Bi-jun; Ke, Miao-la; Chen, Jie-min [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Guangzhou 510060 (China); Li, Li-xia [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Guangzhou 510060 (China); General Hospital of Guangzhou Military Command of PLA, Guangzhou 510010 (China); Fu, Xiang; Wu, Jiang-xue [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Guangzhou 510060 (China); Huang, Wenlin, E-mail: hwenl@mail.sysu.edu.cn [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Guangzhou 510060 (China); Guangdong Provincial Key Laboratory of Tumor-Targeted Drug, Doublle Bioproducts Inc., Guangzhou 510663 (China)

    2013-12-13

    Highlights: •H101 promotes endostatin expression by Ad-Endo via rescuing Ad-Endo replication. •H101 rescued Ad-Endo replication by supplying E1A and E1B19k proteins. •Ad-Endo enhanced the cytotoxicity of H101 in NPC cells. •Ad-Endo and oncolytic Ad H101 have synergistic antitumor effects on NPC. -- Abstract: A replication-deficient adenovirus (Ad) encoding secreted human endostatin (Ad-Endo) has been demonstrated to have promising antiangiogenic and antitumoral effects. The E1B55k-deleted Ad H101 can selectively lyse cancer cells. In this study, we explored the antitumor effects and cross-interactions of Ad-Endo and H101 on nasopharyngeal carcinoma (NPC). The results showed that H101 dramatically promoted endostatin expression by Ad-Endo via rescuing Ad-Endo replication in NPC cells, and the expressed endostatin proteins significantly inhibited the proliferation of human umbilical vein endothelial cells. E1A and E1B19k products are required for the rescuing of H101 to Ad-Endo replication in CNE-1 and CNE-2 cells, but not in C666-1 cells. On the other hand, Ad-Endo enhanced the cytotoxicity of H101 by enhancing Ad replication in NPC cells. The combination of H101 and Ad-Endo significantly inhibited CNE-2 xenografts growth through the increased endostatin expression and Ad replication. These findings indicate that the combination of Ad-Endo gene therapy and oncolytic Ad therapeutics could be promising in comprehensive treatment of NPC.

  16. 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.

  17. 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.

  18. Paired Charge-to-Alanine Mutagenesis of Dengue Virus Type 4 NS5 Generates Mutants with Temperature-Sensitive, Host Range, and Mouse Attenuation Phenotypes

    OpenAIRE

    Hanley, Kathryn A.; Lee, Jay J.; Blaney, Joseph E.; Murphy, Brian R.; Whitehead, Stephen S

    2002-01-01

    Charge-to-alanine mutagenesis of dengue virus type 4 (DEN4) NS5 gene generated a collection of attenuating mutations for potential use in a recombinant live attenuated DEN vaccine. Codons for 80 contiguous pairs of charged amino acids in NS5 were individually mutagenized to create uncharged pairs of alanine residues, and 32 recombinant mutant viruses were recovered from the 80 full-length mutant DEN4 cDNA constructs. These mutant viruses were tested for temperature-sensitive (ts) replication ...

  19. 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).

  20. Efficacy of Recombinant Canine Distemper Virus Expressing Leishmania Antigen against Leishmania Challenge in Dogs.

    Directory of Open Access Journals (Sweden)

    Ryuichi Miura

    Full Text Available Canine distemper virus (CDV vaccination confers long-term protection against CDV reinfection. To investigate the utility of CDV as a polyvalent vaccine vector for Leishmania, we generated recombinant CDVs, based on an avirulent Yanaka strain, that expressed Leishmania antigens: LACK, TSA, or LmSTI1 (rCDV-LACK, rCDV-TSA, and rCDV-LmSTI1, respectively. Dogs immunized with rCDV-LACK were protected against challenge with lethal doses of virulent CDV, in the same way as the parental Yanaka strain. To evaluate the protective effects of the recombinant CDVs against cutaneous leishmaniasis in dogs, dogs were immunized with one recombinant CDV or a cocktail of three recombinant CDVs, before intradermal challenge (in the ears with infective-stage promastigotes of Leishmania major. Unvaccinated dogs showed increased nodules with ulcer formation after 3 weeks, whereas dogs immunized with rCDV-LACK showed markedly smaller nodules without ulceration. Although the rCDV-TSA- and rCDV-LmSTI1-immunized dogs showed little protection against L. major, the cocktail of three recombinant CDVs more effectively suppressed the progression of nodule formation than immunization with rCDV-LACK alone. These results indicate that recombinant CDV is suitable for use as a polyvalent live attenuated vaccine for protection against both CDV and L. major infections in dogs.

  1. CRMAGE: CRISPR Optimized MAGE Recombineering

    Science.gov (United States)

    Ronda, Carlotta; Pedersen, Lasse Ebdrup; Sommer, Morten O. A.; Nielsen, Alex Toftgaard

    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. Using CRMAGE, the recombineering efficiency was between 96.5% and 99.7% for gene recoding of three genomic targets, compared to between 0.68% and 5.4% using traditional recombineering. For modulation of protein synthesis (small insertion/RBS substitution) the efficiency was increased from 6% to 70%. CRMAGE can be multiplexed and enables introduction of at least two mutations in a single round of recombineering with similar efficiencies. PAM-independent loci were targeted using degenerate codons, thereby making it possible to modify any site in the genome. CRMAGE is based on two plasmids 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 oligos and the gRNAs. The CRMAGE platform enables highly efficient and fast genome editing and may open up promising prospective for automation of genome-scale engineering. PMID:26797514

  2. Controlled Release from Recombinant Polymers

    OpenAIRE

    Price, Robert; Poursaid, Azadeh; Ghandehari, Hamidreza

    2014-01-01

    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 tempor...

  3. Preparing Recombinant Gonad Organ Cultures

    OpenAIRE

    sprotocols

    2014-01-01

    Authors: Blanche Capel and Jordan Batchvarov Corresponding author ([]()) ### INTRODUCTION It can be useful to assay migration between any two adjacent tissues during development. This protocol assays cell migration between the gonad and mesonephros using tissue recombination between genetically marked and unmarked tissue, combined with an organ culture technique. First, agar blocks are prepared in a custom-built mold. The size and sh...

  4. Construction of attenuated Salmonella typhimurium Strain expressing Helicobacter pylori conservative region of adhesin antigen and its immunogenicity

    Institute of Scientific and Technical Information of China (English)

    Yang Bai; Ya-Li Zhang; Ji-De Wang; Zhao-Shan Zhang; Dian-Yuan Zhou

    2004-01-01

    AIM: To construct a non-resistant and attenuated Salmonella typhimurium (S. typhimurium) strain which expresses conservative region of adhesion AB of Helicobacter pylori (H pylori) and evaluate its immunogenicity.METHODS: The AB gene amplified by PCR was inserted into the expression vector pYA248 containing asd gene and through two transformations introduced into the delta Cya, delta Crp, delta Asd attenuated Salmonella typhimurium strain, constructing balanced lethal attenuated Salmonella typhimurium strains X4072 (pYA248-AB). Bridged ELISA method was used to measure the expression of AB antigen in sonic ate and culture supernatant. According to the method described by Meacock, stability of the recombinant was evaluated. Semi-lethal capacity test was used to evaluate the safety of recombinant. The immunogenicity of recombinant was evaluated with animal experiments.RESULTS: The attenuated S. typhimurium X4072 (pYA248-AB) which expresses AB was successfully constructed.Furthermore, bridged ELISA assay showed that the content of AB in recombinant X4072 (pYA248- AB) culture supematant was higher than that was in thallus lyric liquor. And after recombinant X4072 (pYA248- AB) was cultured for 100generations without selection pressure, the entire recombinant bacteria selected randomly could grow, and the AB antigen was defected positive by ELISA. The growth curve of the recombinant bacteria showed that the growth states of X4072 (pYA248) and X4072 (pYA248-AB) were basically consistent. The survival rate of C57BL/6 was still 100%, at 30 d after mice taking X4072 (pYA248-AB) 1.0×1010 cfu orally. Oral immunization of mice with X4072 (pYA248-AB)induced a specific immune response.CONCLUSION: In vitro recombinant plasmid appears to be stable and experiments on animals showed that the recombinant strains were safe and immunogenic in vitro,which providing a new live oral vaccine candidate for protection and care of H pylori infection.

  5. Development of a simple and rapid protocol for the production of customized intertypic recombinant polioviruses.

    Science.gov (United States)

    Bessaud, Maël; Delpeyroux, Francis

    2012-12-01

    The three attenuated strains Sabin are used as oral vaccine to immunize against poliomyelitis in many countries. Low vaccine coverage can allow these strains to circulate among non-immunized people, accumulating genetic modifications through nucleotide substitutions and recombination with non-polio enteroviruses. These modifications can induce a loss of attenuation, so promoting the emergence of pathogenic vaccine-derived polioviruses responsible for poliomyelitis outbreaks. In vitro-engineered chimeric viruses containing both Sabin and non-polio sequences constitute a powerful tool for understanding the constraints that drive and limit the recombination events between the Sabin strains and other enteroviruses and to understand the consequences on the viral phenotypic properties of substitutions of large genomic regions due to recombination events. A method was optimized that allowed the rapid production of customized Sabin-derived viruses. By using sequences from Sabin 2 and 3 polioviruses and from non-polio field enteroviruses, several recombinant genomes were engineered by using fusion PCR. The corresponding viruses were recovered after cell transfection. This method was found able to generate rapidly a wide range of unnatural viruses with multiple breakpoints that can be chosen precisely. Furthermore, this method is also suitable to engineer nucleotide deletions, insertions and/or substitutions within a given genome, so increasing the number of unnatural viruses that can be studied. PMID:22939977

  6. A method to generate recombinant Salmonella typhi Ty21a strains expressing multiple heterologous genes using an improved recombineering strategy.

    Science.gov (United States)

    Yu, Bin; Yang, Mei; Wong, Ho Yin Bosco; Watt, Rory M; Song, Erwei; Zheng, Bo-Jian; Yuen, Kwok-Yung; Huang, Jian-Dong

    2011-07-01

    Live attenuated Salmonella enterica serovar Typhi Ty21a (Ty21a) is an important vaccine strain used in clinical studies for typhoid fever and as a vaccine vector for the expression of heterologous antigens. To facilitate the use of Ty21a in such studies, it is desirable to develop improved strategies that enable the stable chromosomal integration and expression of multiple heterologous antigens. The phage λ Red homologous recombination system has previously been used in various gram-negative bacteria species to mediate the accurate replacement of regions of chromosomal DNA with PCR-generated 'targeting cassettes' that contain flanking regions of shared homologous DNA sequence. However, the efficiency of λ Red-mediated recombineering in Ty21a is far lower than in Escherichia coli and other Salmonella typhimurium strains. Here, we describe an improved strategy for recombineering-based methods in Ty21a. Our reliable and efficient method involves the use of linear DNA-targeting cassettes that contain relatively long flanking 'arms' of sequence (ca. 1,000 bp) homologous to the chromosomal target. This enables multiple gene-targeting procedures to be performed on a single Ty21a chromosome in a straightforward, sequential manner. Using this strategy, we inserted three different influenza antigen expression cassettes as well as a green fluorescent protein gene reporter into four different loci on the Ty21a chromosome, with high efficiency and accuracy. Fluorescent microscopy and Western blotting analysis confirmed that strong inducible expression of all four heterologous genes could be achieved. In summary, we have developed an efficient, robust, and versatile method that may be used to construct recombinant Ty21a antigen-expressing strains. PMID:21611798

  7. Recombinant DNA: History of the Controversy.

    Science.gov (United States)

    Vigue, Charles L.; Stanziale, William G.

    1979-01-01

    The hazards associated with recombinant DNA research are presented along with some social implications and the development of recombinant DNA research guidelines by the National Institutes of Health. (SA)

  8. Recombinant innovation and endogenous technological transitions

    NARCIS (Netherlands)

    K. Frenken; L.R. Izquierdo; P. Zeppini

    2012-01-01

    We propose a model of technological transitions based on two different types of innovations. Branching innovations refer to technological improvements along a particular path, while recombinant innovations represent fusions of multiple paths. Recombinant innovations create "short-cuts" which reduce

  9. Attenuation in silica-based optical fibers

    DEFF Research Database (Denmark)

    Wandel, Marie Emilie

    2006-01-01

    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...... well as the viscosity profile a lower attenuation of high index fibers can be obtained. The design of dispersion compensating fibers using the super mode approach is described, the object being to design dispersion compensating fibers for dispersion compensating fiber modules having a low attenuation......, described by a high figure of merit. The major trade offs encountered when designing dispersion compensating fibers with high figure of merit are to obtain a very negative dispersion, low attenuation and low micro bend loss at the same time. The model for predicting the attenuation of high index fibers is...

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

    Science.gov (United States)

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

    2016-01-01

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

  11. Effect of gamma radiation on retroviral recombination.

    OpenAIRE

    Hu, W S; Temin, H M

    1992-01-01

    To elucidate the mechanism(s) of retroviral recombination, we exposed virions to gamma radiation prior to infecting target cells. By using previously described spleen necrosis virus-based vectors containing multiple markers, recombinant proviruses were studied after a single round of retrovirus replication. The current models of retroviral recombination predict that breaking virion RNA should promote minus-strand recombination (forced copy-choice model), decrease or not affect plus-strand rec...

  12. [Recombination in Drosophila in space flight].

    Science.gov (United States)

    Filatova, L P; Vaulina, E N; Lapteva, N Sh; Grozdova, T Ia

    1988-04-01

    An experiment with Drosophila melanogaster males was performed aboard the Artificial Satellite "Kosmos-1667". Mutagenic effects of a 7-day space flight on intergene recombination in chromosome 2 were studied. The space flight factors decreased the frequency of recombination. A model experiment on a laboratory centrifuge demonstrated insignificant increase in recombination frequency caused by acceleration. PMID:3135244

  13. The first EGF domain of coagulation factor IX attenuates cell adhesion and induces apoptosis.

    Science.gov (United States)

    Ishikawa, Tomomi; Kitano, Hisataka; Mamiya, Atsushi; Kokubun, Shinichiro; Hidai, Chiaki

    2016-07-01

    Coagulation factor IX (FIX) is an essential plasma protein for blood coagulation. The first epidermal growth factor (EGF) motif of FIX (EGF-F9) has been reported to attenuate cell adhesion to the extracellular matrix (ECM). The purpose of the present study was to determine the effects of this motif on cell adhesion and apoptosis. Treatment with a recombinant EGF-F9 attenuated cell adhesion to the ECM within 10 min. De-adhesion assays with native FIX recombinant FIX deletion mutant proteins suggested that the de-adhesion activity of EGF-F9 requires the same process of FIX activation as that which occurs for coagulation activity. The recombinant EGF-F9 increased lactate dehydrogenase (LDH) activity release into the medium and increased the number of cells stained with annexin V and activated caspase-3, by 8.8- and 2.7-fold respectively, indicating that EGF-F9 induced apoptosis. Activated caspase-3 increased very rapidly after only 5 min of administration of recombinant EGF-F9. Treatment with EGF-F9 increased the level of phosphorylated p38 mitogen-activated protein kinase (MAPK), but not that of phosphorylated MAPK 44/42 or c-Jun N-terminal kinase (JNK). Inhibitors of caspase-3 suppressed the release of LDH. Caspase-3 inhibitors also suppressed the attenuation of cell adhesion and phosphorylation of p38 MAPK by EGF-F9. Our data indicated that EGF-F9 activated signals for apoptosis and induced de-adhesion in a caspase-3 dependent manner. PMID:27129300

  14. Recombinant human erythropoietin attenuates weight loss in a murine cancer cachexia model.

    NARCIS (Netherlands)

    Halteren, H.K. van; Bongaerts, G.P.A.; Verhagen, C.A.H.H.V.M.; Kamm, Y.J.L.; Willems, J.L.; Grutters, G.J.; Koopman, J.P.; Wagener, D.J.T.

    2004-01-01

    BACKGROUND: Within hypoxic tumor regions anaerobic dissimilation of glucose is the sole source of energy generation. It yields only 5% of the ATP that is normally gained by means of oxidative glucose catabolism. The increased need for glucose may aggravate cancer cachexia. We investigated the impact

  15. Immune responses of pigs immunized with a recombinant porcine reproductive and respiratory syndrome virus expressing porcine GM-CSF.

    Science.gov (United States)

    Li, Zhijun; Wang, Gang; Wang, Yan; Zhang, Chong; Huang, Baicheng; Li, Qiongyi; Li, Liangliang; Xue, Biyun; Ding, Peiyang; Cai, Xuehui; Wang, Chengbao; Zhou, En-Min

    2015-11-15

    Porcine reproductive and respiratory syndrome virus (PRRSV) has spread worldwide, causing huge economic losses to the swine industry. The current PRRSV vaccines have failed to provide broad protection against various strains. Granulocyte macrophage colony-stimulating factor (GM-CSF), an efficacious adjuvant, has been shown to enhance the immunogenicity of various vaccines. The purpose of this study was to construct a recombinant live attenuated PRRSV that expresses porcine GM-CSF (pGM-CSF) and evaluate the immune responses of pigs immunized with the recombinant virus. The results showed that the recombinant PRRSV was successfully rescued and had similar growth properties to parental virus grown in Marc-145 cells. The recombinant virus was stable for 10 passages in cell culture. Pigs intramuscularly immunized with the recombinant virus produced a similar humoral response to that elicited using parental virus. With regard to cell-mediated immunity assessed in peripheral blood, the recombinant virus induced higher proportion of CD4(+)CD8(+) double-positive T cells (DPT), higher IFN-γ level at 0 and 7 days post-challenge (DPC), and lower viremia at 21 DPC than pigs immunized with parental virus. These results indicate that recombinant PRRSV expressing pGM-CSF can induce a significant higher cellular immune response and reduce the persistent infection compared pigs vaccinated with the parental virus. This is first report of evaluation of immune response in pigs elicited by a recombinant live attenuated PRRSV expressing porcine GM-CSF. It may represent a novel strategy for future development of genetic engineered vaccines against PRRSV infection. PMID:26300317

  16. Imaging Rayleigh wave attenuation with USArray

    Science.gov (United States)

    Bao, Xueyang; Dalton, Colleen A.; Jin, Ge; Gaherty, James B.; Shen, Yang

    2016-07-01

    The EarthScope USArray provides an opportunity to obtain detailed images of the continental upper mantle at an unprecedented scale. The majority of mantle models derived from USArray data to date contain spatial variations in seismic-wave speed; however, in many cases these data sets do not by themselves allow a non-unique interpretation. Joint interpretation of seismic attenuation and velocity models can improve upon the interpretations based only on velocity and provide important constraints on the temperature, composition, melt content, and volatile content of the mantle. The surface wave amplitudes that constrain upper-mantle attenuation are sensitive to factors in addition to attenuation, including the earthquake source excitation, focusing and defocusing by elastic structure, and local site amplification. Because of the difficulty of isolating attenuation from these other factors, little is known about the attenuation structure of the North American upper mantle. In this study, Rayleigh wave traveltime and amplitude in the period range 25-100 s are measured using an interstation cross-correlation technique, which takes advantage of waveform similarity at nearby stations. Several estimates of Rayleigh wave attenuation and site amplification are generated at each period, using different approaches to separate the effects of attenuation and local site amplification on amplitude. It is assumed that focusing and defocusing effects can be described by the Laplacian of the traveltime field. All approaches identify the same large-scale patterns in attenuation, including areas where the attenuation values are likely contaminated by unmodelled focusing and defocusing effects. Regionally averaged attenuation maps are constructed after removal of the contaminated attenuation values, and the variations in intrinsic shear attenuation that are suggested by these Rayleigh wave attenuation maps are explored.

  17. Selection of Recombinant Human Antibodies.

    Science.gov (United States)

    Tomszak, Florian; Weber, Susanne; Zantow, Jonas; Schirrmann, Thomas; Hust, Michael; Frenzel, André

    2016-01-01

    Since the development of therapeutic antibodies the demand of recombinant human antibodies is steadily increasing. Traditionally, therapeutic antibodies were generated by immunization of rat or mice, the generation of hybridoma clones, cloning of the antibody genes and subsequent humanization and engineering of the lead candidates. In the last few years, techniques were developed that use transgenic animals with a human antibody gene repertoire. Here, modern recombinant DNA technologies can be combined with well established immunization and hybridoma technologies to generate already affinity maturated human antibodies. An alternative are in vitro technologies which enabled the generation of fully human antibodies from antibody gene libraries that even exceed the human antibody repertoire. Specific antibodies can be isolated from these libraries in a very short time and therefore reduce the development time of an antibody drug at a very early stage.In this review, we describe different technologies that are currently used for the in vitro and in vivo generation of human antibodies. PMID:27236551

  18. Mechanisms of sister chromatid recombination

    International Nuclear Information System (INIS)

    Studies using T948 as a model system have been carried out aimed at elucidating the mechanism of sister chromatid recombination (SCR). Characterization of U.V. light- and x-ray-induced SCR, the relationiship between SCR induction and DNA repair using rad mutations, and the relationship between SCR induction and the time of cell division using cdc mutations are presented. It has been supposed that SCR is induced at the phase of S-G2 following DNA replication, that postreplication break of DNA strands is strongly involved in the induction of SCR, and that induction type of SCR, i.e., conversion type or recombination type, is dependent upon the type of molecular damage of DNA. (Namekawa, K.)

  19. Recombinant modified vaccinia virus Ankara-based malaria vaccines.

    Science.gov (United States)

    Sebastian, Sarah; Gilbert, Sarah C

    2016-01-01

    A safe and effective malaria vaccine is a crucial part of the roadmap to malaria elimination/eradication by the year 2050. Viral-vectored vaccines based on adenoviruses and modified vaccinia virus Ankara (MVA) expressing malaria immunogens are currently being used in heterologous prime-boost regimes in clinical trials for induction of strong antigen-specific T-cell responses and high-titer antibodies. Recombinant MVA is a safe and well-tolerated attenuated vector that has consistently shown significant boosting potential. Advances have been made in large-scale MVA manufacture as high-yield producer cell lines and high-throughput purification processes have recently been developed. This review describes the use of MVA as malaria vaccine vector in both preclinical and clinical studies in the past 5 years. PMID:26511884

  20. Recombinations of Busy Beaver Machines

    OpenAIRE

    Bátfai, Norbert

    2009-01-01

    Many programmers belive that Turing-based machines cannot think. We also believe in this, however it is interesting to note that the most sophisticated machines are not programmed by human beings. We have only discovered them. In this paper, using well-known Busy Beaver and Placid Platypus machines, we generate further very similar, but not exactly the same machines. We have found a recombinated BB_5 machine which can make 70.740.809 steps before halting.

  1. Recombinant erythropoietin in clinical practice

    OpenAIRE

    Ng, T; Marx, G.; Littlewood, T; Macdougall, I

    2003-01-01

    The introduction of recombinant human erythropoietin (RHuEPO) has revolutionised the treatment of patients with anaemia of chronic renal disease. Clinical studies have demonstrated that RHuEPO is also useful in various non-uraemic conditions including haematological and oncological disorders, prematurity, HIV infection, and perioperative therapies. Besides highlighting both the historical and functional aspects of RHuEPO, this review discusses the applications of RHuEPO in clinical practice a...

  2. Recombinant antibodies and tumor targeting

    OpenAIRE

    Sheikholvaezin, Ali

    2006-01-01

    Different antibody derived constructs are rapidly advancing as putative tools for treatment of malignant diseases. Antibody engineering has added significant new technologies to modify size, affinities, solubility, stability and biodistribution properties for immunoconjugates. In the present thesis, the aim was to increase our knowledge on how new recombinant antibodies could be tailored to optimize localization to experimental tumors in mice. One hybridoma, producing the monoclonal antibody ...

  3. 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...

  4. Effect of gamma radiation on retroviral recombination.

    Science.gov (United States)

    Hu, W S; Temin, H M

    1992-07-01

    To elucidate the mechanism(s) of retroviral recombination, we exposed virions to gamma radiation prior to infecting target cells. By using previously described spleen necrosis virus-based vectors containing multiple markers, recombinant proviruses were studied after a single round of retrovirus replication. The current models of retroviral recombination predict that breaking virion RNA should promote minus-strand recombination (forced copy-choice model), decrease or not affect plus-strand recombination (strand displacement/assimilation model), and shift plus-strand recombination towards the 3' end of the genome. However, we found that while gamma irradiation of virions reduced the amount of recoverable viral RNA, it did not primarily cause breaks. Thus, the frequency of selected recombinants was not significantly altered with greater doses of radiation. In spite of this, the irradiation did decrease the number of recombinants with only one internal template switch. As a result, the average number of additional internal template switches in the recombinant proviruses increased from 0.7 to 1.4 as infectivity decreased to 6%. The unselected internal template switches tended to be 5' of the selected crossover even in the recombinants from irradiated viruses, inconsistent with a plus-strand recombination mechanism. PMID:1602553

  5. SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Joel Walls; M.T. Taner; Naum Derzhi; Gary Mavko; Jack Dvorkin

    2003-12-01

    We have developed and tested technology for a new type of direct hydrocarbon detection. The method uses inelastic rock properties to greatly enhance the sensitivity of surface seismic methods to the presence of oil and gas saturation. These methods include use of energy absorption, dispersion, and attenuation (Q) along with traditional seismic attributes like velocity, impedance, and AVO. Our approach is to combine three elements: (1) a synthesis of the latest rock physics understanding of how rock inelasticity is related to rock type, pore fluid types, and pore microstructure, (2) synthetic seismic modeling that will help identify the relative contributions of scattering and intrinsic inelasticity to apparent Q attributes, and (3) robust algorithms that extract relative wave attenuation attributes from seismic data. This project provides: (1) Additional petrophysical insight from acquired data; (2) Increased understanding of rock and fluid properties; (3) New techniques to measure reservoir properties that are not currently available; and (4) Provide tools to more accurately describe the reservoir and predict oil location and volumes. These methodologies will improve the industry's ability to predict and quantify oil and gas saturation distribution, and to apply this information through geologic models to enhance reservoir simulation. We have applied for two separate patents relating to work that was completed as part of this project.

  6. Fusion of the BCL9 HD2 domain to E1A increases the cytopathic effect of an oncolytic adenovirus that targets colon cancer cells

    International Nuclear Information System (INIS)

    The Wnt signaling pathway is activated by mutations in the APC and β-catenin genes in many types of human cancer. β-catenin is stabilized by these mutations and activates transcription in part by acting as a bridge between Tcf/LEF proteins and the HD2 domain of the BCL9 coactivator. We have previously described oncolytic adenoviruses with binding sites for Tcf/LEF transcription factors inserted into the early viral promoters. These viruses replicate selectively in cells with activation of the Wnt pathway. To increase the activity of these viruses we have fused the viral transactivator E1A to the BCL9 HD2 domain. Luciferase assays, co-immunoprecipitation and Western blotting, immunofluorescent cell staining and cytopathic effect assays were used to characterize the E1A-HD2 fusion protein and virus in vitro. Growth curves of subcutaneous SW620 colon cancer xenografts were used to characterize the virus in vivo. The E1A-HD2 fusion protein binds to β-catenin in vivo and activates a Tcf-regulated luciferase reporter better than wild-type E1A in cells with activated Wnt signaling. Expression of the E1A-HD2 protein promotes nuclear import of β-catenin, mediated by the strong nuclear localization signal in E1A. Tcf-regulated viruses expressing the fusion protein show increased expression of viral proteins and a five-fold increase in cytopathic effect (CPE) in colorectal cancer cell lines. There was no change in viral protein expression or CPE in HeLa cells, indicating that E1A-HD2 viruses retain selectivity for cells with activation of the Wnt signaling pathway. Despite increasing the cytopathic effect of the virus in vitro, fusion of the HD2 domain to E1A did not increase the burst size of the virus in vitro or the anti-tumor effect of the virus in an SW620 xenograft model in vivo. Despite an increase in the nuclear pool of β-catenin, the effects on viral activity in colon cancer cells were small, suggesting that factors acting downstream of β-catenin are limiting

  7. Fusion of the BCL9 HD2 domain to E1A increases the cytopathic effect of an oncolytic adenovirus that targets colon cancer cells

    Directory of Open Access Journals (Sweden)

    Pittet Anne-Laure

    2006-10-01

    Full Text Available Abstract Background The Wnt signaling pathway is activated by mutations in the APC and β-catenin genes in many types of human cancer. β-catenin is stabilized by these mutations and activates transcription in part by acting as a bridge between Tcf/LEF proteins and the HD2 domain of the BCL9 coactivator. We have previously described oncolytic adenoviruses with binding sites for Tcf/LEF transcription factors inserted into the early viral promoters. These viruses replicate selectively in cells with activation of the Wnt pathway. To increase the activity of these viruses we have fused the viral transactivator E1A to the BCL9 HD2 domain. Methods Luciferase assays, co-immunoprecipitation and Western blotting, immunofluorescent cell staining and cytopathic effect assays were used to characterize the E1A-HD2 fusion protein and virus in vitro. Growth curves of subcutaneous SW620 colon cancer xenografts were used to characterize the virus in vivo. Results The E1A-HD2 fusion protein binds to β-catenin in vivo and activates a Tcf-regulated luciferase reporter better than wild-type E1A in cells with activated Wnt signaling. Expression of the E1A-HD2 protein promotes nuclear import of β-catenin, mediated by the strong nuclear localization signal in E1A. Tcf-regulated viruses expressing the fusion protein show increased expression of viral proteins and a five-fold increase in cytopathic effect (CPE in colorectal cancer cell lines. There was no change in viral protein expression or CPE in HeLa cells, indicating that E1A-HD2 viruses retain selectivity for cells with activation of the Wnt signaling pathway. Despite increasing the cytopathic effect of the virus in vitro, fusion of the HD2 domain to E1A did not increase the burst size of the virus in vitro or the anti-tumor effect of the virus in an SW620 xenograft model in vivo. Conclusion Despite an increase in the nuclear pool of β-catenin, the effects on viral activity in colon cancer cells were small

  8. [Construction of recombinant yellow fever virus 17D containing 2A fragment as a vaccine vector].

    Science.gov (United States)

    Xiaowu, Pang; Fu, Wen-Chuan; Guo, Yin-Han; Zhang, Li-Shu; Xie, Tian-Pei; Xinbin, Gu

    2006-05-01

    The Yellow Fever (YF) vaccine, an attenuated yellow fever 17D (YF-17D) live vaccine, is one of the most effective and safest vaccines in the world and is regarded as one of the best candidates for viral expression vector. We here first reported in China the construction and characterization of the recombinant expression vector of yellow fever 17D which contained the proteinase 2A fragment of foot-and-mouth disease virus (FMDV). Three cDNA fragments representing the full-length YF-17D genome, named 5'-end cDNA (A), 3'-end cDNA (B) and middle cDNA (C), were obtained by reverse transcription polymerase chain reaction (RT-PCR), together with the introduction of SP6 enhancer, necessary restriction sites and overlaps for homologous recombination in yeast. Fragment A and B were then introduced into pRS424 in turn by DNA recombination, followed by transfection of fragment C and the recombinant pRS424 containing A and B (pRS-A-B) into yeast. A recombinant vector containing full length cDNA of YF-17D (pRS-YF) was obtained by screening on medium lack of tryptophan and uracil. A recombinant YF-17D expression vector containing FMDV-2A gene fragment (pRS-YF-2A1) was then constructed by methods of DNA recombination and homologous recombination in yeast described above. In vitro transcription of the recombinant vector pRS-YF-2A1 was then carried out and introduced into BHK-21 cells by electroporation. Results of indirect immunofluorescence assay (IFA) and titer determination showed a stable infectious recombinant virus was gotten, whose features such as growth curve were similar to those of the parental YF-17D. The results suggest that the recombinant vector pRS-YF-2A1, by introduction of heterogenous genes via 2A region, is potential to be an effective live vaccine expression vector. PMID:16755933

  9. 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

  10. 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

    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...... using GalK 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...

  11. 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.

  12. 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. PMID:24442504

  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. Attenuation characteristics of gypsum wallboard

    International Nuclear Information System (INIS)

    Increased cost of lead is promoting enhanced usage of common building materials for shielding in diagnostic medical and dental facilities where only a few half-value layers (HVLs) are needed. Attenuation of primary beam X-ray photons in gypsum wallboard as a function of kVp, filtration, and wallboard thickness have been measured. Findings, obtained using a Victoreen 555 with an 0.1 DAS probe in poor geometry, are substantially in agreement with the sparse data in the literature but extend to thicker wall configurations and different kVp and filtration parameters. These findings are of value in maximizing the benefit/cost ratio for diagnostic shielding, and strengthen the conviction that, where used for shielding purposes, common building materials must be installed carefully and HVL-depth dependence considered thoroughly. (author)

  15. 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...... 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...

  16. Immune Events Associated with High Level Protection against Schistosoma japonicum Infection in Pigs Immunized with UV-Attenuated Cercariae

    OpenAIRE

    Tian, Fang; Lin, Dandan; Wu, Jingjiao; Gao, Yanan; Zhang, Donghui; Ji, Minjun; Wu, Guanling

    2010-01-01

    Background The vaccination of radiation-attenuated Schistosoma japonicum cercariae can induce effective protection in artiodactyl, but the immune events related to protective immunity are not fully understood. To provide a paradigm for a human recombinant antigen vaccine, we have undertaken a vaccination and challenge experiment in pigs, which was recognized as an appropriate animal model in this type of study because of their similarity to human in immunology, and investigated the relative i...

  17. Adapted ECHO-7 virus Rigvir immunotherapy (oncolytic virotherapy) prolongs survival in melanoma patients after surgical excision of the tumour in a retrospective study.

    Science.gov (United States)

    Doniņa, Simona; Strēle, Ieva; Proboka, Guna; Auziņš, Jurgis; Alberts, Pēteris; Jonsson, Björn; Venskus, Dite; Muceniece, Aina

    2015-10-01

    An oncolytic, nonpathogenic ECHO-7 virus adapted for melanoma that has not been genetically modified (Rigvir) is approved and registered for virotherapy, an active and specific immunotherapy, in Latvia since 2004. The present retrospective study was carried out to determine the effectiveness of Rigvir in substage IB, IIA, IIB and IIC melanoma patients on time to progression and overall survival. White patients (N=79) who had undergone surgical excision of the primary melanoma tumour were included in this study. All patients were free from disease after surgery and classified into substages IB, IIA, IIB and IIC. Circulating levels of clinical chemistry parameters were recorded. Survival was analysed by Cox regression. Rigvir significantly (PRigvir was statistically significantly different: hazard ratio 6.27 for all, 4.39 for substage IIA-IIB-IIC and 6.57 for substage IIB-IIC patients. The follow-up period was not statistically different between both treatment groups. These results indicate that the patients treated with Rigvir had a 4.39-6.57-fold lower mortality than those under observation. In this study, there was no untoward side effect or discontinuation of Rigvir treatment. Safety assessment of adverse events graded according to NCI CTCAE did not show any value above grade 2 in Rigvir-treated patients. In conclusion, Rigvir significantly prolongs survival in early-stage melanoma patients without any side effect. PMID:26193376

  18. Simple parameterization of nuclear attenuation data

    CERN Document Server

    Akopov, N; Akopov, Z

    2007-01-01

    Based on the nuclear attenuation data obtained by the HERMES experiment on nitrogen and krypton nuclei, it is shown that the nuclear attenuation $R_M^{h}$ can be parametrised in a form of a linear polynomial $P_1=a_{11}$ + $\\tau a_{12}$, where $\\tau$ is the formation time, which depends on the energy of the virtual photon $\

  19. Docking-mechanism attenuator with electromechanical damper

    Science.gov (United States)

    Syromyatnikov, V. S.

    1971-01-01

    Theoretical and practical problems involved in the application of electromechanical damping for spacecraft docking-mechanism attenuation are discussed. Some drawbacks of hydraulic dampers used for the purpose are pointed out. The basic scheme of the attenuator with the electromechanical damper is given.

  20. Theory of standing spin-wave attenuation

    International Nuclear Information System (INIS)

    Exchange attenuation of standing spin waves is calculated for an ultrathin magnetic of the order of exchange length thick. Because of the boundary conditions the wave vectors of spin waves in such films high values that are proportional to the inverse film thickness. The exchange attenuation at such wave vectors becomes dominant and can result in smearing of the standing spin wave spectrum

  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...

  2. Comparison of 2 synthetically generated recombinant prions

    OpenAIRE

    Zhang, Yi; Wang, Fei; Wang, Xinhe; Zhang, Zhihong; Xu, Yuanyuan; Yu, Guohua; Yuan, Chonggang; Ma, Jiyan

    2014-01-01

    Prion is a protein-conformation-based infectious agent causing fatal neurodegenerative diseases in humans and animals. Our previous studies revealed that in the presence of cofactors, infectious prions can be synthetically generated in vitro with bacterially expressed recombinant prion protein (PrP). Once initiated, the recombinant prion is able to propagate indefinitely via serial protein misfolding cyclic amplification (sPMCA). In this study, we compared 2 separately initiated recombinant p...

  3. Impact of recombination on bacterial evolution

    OpenAIRE

    Didelot, Xavier; Maiden, Martin C. J.

    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...

  4. Recombination rate variation in closely related species

    OpenAIRE

    Smukowski, C S; Noor, M A F

    2011-01-01

    Despite their importance to successful meiosis and various evolutionary processes, meiotic recombination rates sometimes vary within species or between closely related species. For example, humans and chimpanzees share virtually no recombination hotspot locations in the surveyed portion of the genomes. However, conservation of recombination rates between closely related species has also been documented, raising an apparent contradiction. Here, we evaluate how and why conflicting patterns of r...

  5. 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.

  6. 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...... recombination leads to a large overestimation of the substitution rate heterogeneity and the loss of the molecular clock. These results are discussed in relation to viral and mtDNA data sets. Udgivelsesdato: 2000-Oct...

  7. RNA recombination in animal and plant viruses.

    OpenAIRE

    Lai, M M

    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 ...

  8. Ultrasound fields in an attenuating medium

    DEFF Research Database (Denmark)

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

    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...

  9. 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.

  10. Experimental recombination rates for highly charged ions

    International Nuclear Information System (INIS)

    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)

  11. Genetic characterisation of attenuated SAD rabies virus strains used for oral vaccination of wildlife.

    Science.gov (United States)

    Geue, Lutz; Schares, Susann; Schnick, Christina; Kliemt, Jeannette; Beckert, Aline; Freuling, Conrad; Conraths, Franz J; Hoffmann, Bernd; Zanoni, Reto; Marston, Denise; McElhinney, Lorraine; Johnson, Nicholas; Fooks, Anthony R; Tordo, Noel; Müller, Thomas

    2008-06-19

    The elimination of rabies from the red fox (Vulpes vulpes) in Western Europe has been achieved by the oral rabies vaccination (ORV) of wildlife with a range of attenuated rabies virus strains. With the exception of the vaccinia rabies glycoprotein recombinant vaccine (VRG), all strains were originally derived from a common ancestor; the Street Alabama Dufferin (SAD) field strain. However, after more than 30 years of ORV it is still not possible to distinguish these vaccine strains and there is little information on the genetic basis for their attenuation. We therefore sequenced and compared the full-length genome of five commercially available SAD vaccine viruses (SAD B19, SAD P5/88, SAG2, SAD VA1 and SAD Bern) and four other SAD strains (the original SAD Bern, SAD VA1, ERA and SAD 1-3670 Wistar). Nucleotide sequencing allowed identifying each vaccine strain unambiguously. Phylogenetic analysis revealed that the majority of the currently used commercial attenuated rabies virus vaccines appear to be derived from SAD B19 rather than from SAD Bern. One commercially available vaccine virus did not contain the SAD strain mentioned in the product information of the producer. Two SAD vaccine strains appeared to consist of mixed genomic sequences. Furthermore, in-del events targeting A-rich sequences (in positive strand) within the 3' non-coding regions of M and G genes were observed in SAD-derivates developed in Europe. Our data also supports the idea of a possible recombination that had occurred during the derivation of the European branch of SAD viruses. If confirmed, this recombination event would be the first one reported among RABV vaccine strains. PMID:18485548

  12. Recombinant BCG: Innovations on an Old Vaccine. Scope of BCG Strains and Strategies to Improve Long-Lasting Memory

    OpenAIRE

    da Costa, Adeliane Castro; Nogueira, Sarah Veloso; Kipnis, André; Junqueira-Kipnis, Ana Paula

    2014-01-01

    Bacille Calmette–Guérin (BCG), an attenuated vaccine derived from Mycobacterium bovis, is the current vaccine of choice against tuberculosis (TB). Despite its protection against active TB in children, BCG has failed to protect adults against TB infection and active disease development, especially in developing countries where the disease is endemic. Currently, there is a significant effort toward the development of a new TB vaccine. This review article aims to address publications on recombin...

  13. Oral immunization and protection of raccoons (Procyon lotor) with a vaccinia-rabies glycoprotein recombinant virus vaccine.

    OpenAIRE

    Rupprecht, C E; Wiktor, T. J.; Johnston, D. H.; Hamir, A N; Dietzschold, B; Wunner, W H; Glickman, L T; Koprowski, H

    1986-01-01

    Animal rabies control has been frustrated by the existence of multiple wildlife reservoirs and the lack of efficacious oral vaccines. In this investigation, raccoons fed a vaccinia-rabies glycoprotein recombinant virus in a sponge bait developed rabies virus-neutralizing antibody (0.6-54.0 units) and resisted street rabies virus infection 28 and 205 days after feeding. Additional raccoons immunized by oral infusion with attenuated antigenic variants of rabies virus strains CVS-11 and ERA fail...

  14. 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.

  15. Plasmodium falciparum: attenuation by irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Waki, S.; Yonome, I.; Suzuki, M.

    1983-12-01

    The effect of irradiation on the in vitro growth of Plasmodium falciparum was investigated. The cultured malarial parasites at selected stages of development were exposed to gamma rays and the sensitivity of each stage was determined. The stages most sensitive to irradiation were the ring forms and the early trophozoites; late trophozoites were relatively insensitive. The greatest resistance was shown when parasites were irradiated at a time of transition from the late trophozoite and schizont stages to young ring forms. The characteristics of radiosensitive variation in the parasite cycle resembled that of mammalian cells. Growth curves of parasites exposed to doses of irradiation upto 150 gray had the same slope as nonirradiated controls but parasites which were exposed to 200 gray exhibited a growth curve which was less steep than that for parasites in other groups. Less than 10 organisms survived from the 10(6) parasites exposed to this high dose of irradiation; the possibility exists of obtaining radiation-attenuated P. falciparum.

  16. Beta attenuation transmission system (BATS)

    International Nuclear Information System (INIS)

    The beta attenuation transmission system (BATS) is an automated radiation gauge designed for quantitative measurement of component thickness in explosive detonators. The BATS was designed and built by Group M-1, the Nondestructive Testing Group, of the Los Alamos Scientific Laboratory to measure the areal thickness, in mg/cm2, of a cylinder of high explosive (HE) enclosed within a plastic holder. The problem is to determine the density of the HE. A 90Sr source is collimated by a 0.25 x 1.59-mm slit, and the transmitted beta-particle flux is detected by a plastic scintillator, coupled to a photomultiplier tube. The detonator is transported through the radiation beam by a leadscrew, ballnut, stepping-motor combination. Continuous analog position data are available, derived from the output from a linear-actuated potentiometer attached to the scanner. A linear electrometer amplifies the detected signal, which is then integrated for a preselected time, to obtain the desired statistical accuracy. A microprocessor (μP) is used to control the scanner position and to make the data readings at the assigned positions. The data are stored, and, at the completion of the scan, are processed into the desired format. The final answer is displayed to the operator or output to a peripheral device for permanent record. The characteristics of the radiation source, the collimator, the signal detection and conditioning, and the final results are described in detail. The scanner and the microprocessor control system are briefly outlined

  17. Beta attenuation transmission system (BATS)

    Energy Technology Data Exchange (ETDEWEB)

    Hagan, R.C.; Fullbright, H.J.

    1977-01-01

    The beta attenuation transmission system (BATS) is an automated radiation gauge designed for quantitative measurement of component thickness in explosive detonators. The BATS was designed and built by Group M-1, the Nondestructive Testing Group, of the Los Alamos Scientific Laboratory to measure the areal thickness, in mg/cm/sup 2/, of a cylinder of high explosive (HE) enclosed within a plastic holder. The problem is to determine the density of the HE. A /sup 90/Sr source is collimated by a 0.25 x 1.59-mm slit, and the transmitted beta-particle flux is detected by a plastic scintillator, coupled to a photomultiplier tube. The detonator is transported through the radiation beam by a leadscrew, ballnut, stepping-motor combination. Continuous analog position data are available, derived from the output from a linear-actuated potentiometer attached to the scanner. A linear electrometer amplifies the detected signal, which is then integrated for a preselected time, to obtain the desired statistical accuracy. A microprocessor (..mu..P) is used to control the scanner position and to make the data readings at the assigned positions. The data are stored, and, at the completion of the scan, are processed into the desired format. The final answer is displayed to the operator or output to a peripheral device for permanent record. The characteristics of the radiation source, the collimator, the signal detection and conditioning, and the final results are described in detail. The scanner and the microprocessor control system are briefly outlined.

  18. Attenuation Tomography of the Upper Mantle

    Science.gov (United States)

    Adenis, A.; Debayle, E.; Ricard, Y. R.

    2014-12-01

    We present a 3-D model of surface wave attenuation in the upper mantle. The model is constrained by a large data set of fundamental and higher Rayleigh mode observations. This data set consists of about 1,800,000 attenuation curves measured in the period range 50-300s by Debayle and Ricard (2012). A careful selection allows us to reject data for which measurements are likely biased by the poor knowledge of the scalar seismic moment or by a ray propagation too close to a node of the source radiation pattern. For each epicenter-station path, elastic focusing effects due to seismic heterogeneities are corrected using DR2012 and the data are turned into log(1/Q). The selected data are then combined in a tomographic inversion using the non-linear least square formalism of Tarantola and Valette (1982). The obtained attenuation maps are in agreement with the surface tectonic for periods and modes sensitive to the top 200km of the upper mantle. Low attenuation regions correlate with continental shields while high attenuation regions are located beneath young oceanic regions. The attenuation pattern becomes more homogeneous at depths greater than 200 km and the maps are dominated by a high quality factor signature beneath slabs. We will discuss the similarities and differences between the tomographies of seismic velocities and of attenuations.

  19. Local Production of Tumor Necrosis Factor Encoded by Recombinant Vaccinia Virus is Effective in Controlling Viral Replication in vivo

    Science.gov (United States)

    Sambhi, Sharan K.; Kohonen-Corish, Maija R. J.; Ramshaw, Ian A.

    1991-05-01

    Tumor necrosis factor (TNF) has pleiotropic effects on a wide variety of cell types. In vitro studies have demonstrated that TNF has antiviral properties and is induced in response to viral infections. However, a role for TNF in the antiviral immune response of the host has yet to be demonstrated. Here we describe the construction of and studies using a recombinant vaccinia virus that encodes the gene for murine TNF-α. By comparing the replication of and immune responses elicited by the TNF-encoding virus to a similarly constructed control virus, we hoped to observe immunobiological effects of TNF in the host. The in vivo experiments with this recombinant virus demonstrate that the localized production of TNF-α during a viral infection leads to the rapid and efficient clearance of the virus in normal mice and attenuates the otherwise lethal pathogenicity of the virus in immunodeficient animals. This attenuation occurs early in the infection (by postinfection hour 24) and is not due to the enhancement of cellular or antibody responses by the vaccinia virus-encoded TNF. This evidence suggests that attenuation of the recombinant virus is due to a direct antiviral effect of TNF on cells at the site of infection. Therefore, these results support the suggestion that TNF produced by immune cells may be an important effector mechanism of viral clearance in vivo.

  20. Heterogeneity in recombinant protein production

    DEFF Research Database (Denmark)

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

    2012-01-01

    A crucial step in biotechnology is the scale-up process. Normally, lab scale verification and optimization of production processes and strains are performed in small reactors with perfect mixing and hence the cells experience a homogenous environment. The gradients that occur in industrial scale...... bioreactors are often not taken into consideration in these experiments. Gradients occur due to insufficient mixing in the reactor, and affect the process in a variety of ways. When cells travel through the reactor and encounter different substrate concentrations, oxygen availability, pH, temperature, etc....... the cell physiology is affected. Cells are stressed, and this may severely affect growth, by-product accumulation, biomass yield and recombinant product yield. The stress caused by exposure to divergent microenvironments, genetic differences of individual cells, differing cell cycle stage and cell age...

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

    International Nuclear Information System (INIS)

    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

  2. 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.

  3. 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...... ultrasound pulse, which includes a maximum likelihood attenuation estimator, is derived. The results of this correspondence are of great importance for deconvolution and attenuation imaging in medical ultrasound...

  4. 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...

  5. Recombinant organisms for production of industrial products

    OpenAIRE

    Adrio, Jose-Luis; Demain, Arnold L.

    2009-01-01

    A revolution in industrial microbiology was sparked by the discoveries of ther double-stranded structure of DNA and the development of recombinant DNA technology. Traditional industrial microbiology was merged with molecular biology to yield improved recombinant processes for the industrial production of primary and secondary metabolites, protein biopharmaceuticals and industrial enzymes. Novel genetic techniques such as metabolic engineering, combinatorial biosynthesis and molecular breeding...

  6. 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.

  7. Recombinant Vaccinia Virus: Immunization against Multiple Pathogens

    Science.gov (United States)

    Perkus, Marion E.; Piccini, Antonia; Lipinskas, Bernard R.; Paoletti, Enzo

    1985-09-01

    The coding sequences for the hepatitis B virus surface antigen, the herpes simplex virus glycoprotein D, and the influenza virus hemagglutinin were inserted into a single vaccinia virus genome. Rabbits inoculated intravenously or intradermally with this polyvalent vaccinia virus recombinant produced antibodies reactive to all three authentic foreign antigens. In addition, the feasibility of multiple rounds of vaccination with recombinant vaccinia virus was demonstrated.

  8. Electron-ion recombination at low energy

    International Nuclear Information System (INIS)

    The work is based on results obtained with a merged-beams experiment. A beam of electronics with a well characterized density and energy distribution was merged with a fast, monoenergetic ion beam. Results have been obtained for radiative recombination and dielectronic recombination at low relative energies (0 to ∼70eV). The obtained energy resolution was improved by about a factor of 30. High vacuum technology was used to suppress interactions with electrons from the environments. The velocity distribution of the electron beam was determined. State-selective dielectronic-recombination measurements were performable. Recombination processes were studied. The theoretical background for radiative recombination and Kramers' theory are reviewed. The quantum mechanical result and its relation to the semiclassical theory is discussed. Radiative recombination was also measured with several different non-bare ions, and the applicability of the semiclassical theory to non-bare ions was investigated. The use of an effective charge is discussed. For dielectronic recombination, the standard theoretical approach in the isolated resonance and independent-processes approximation is debated. The applicability of this method was tested. The theory was able to reproduce most of the experimental data except when the recombination process was sensitive to couplings between different electronic configurations. The influence of external perturbing electrostatic fields is discussed. (AB) (31 refs.)

  9. Recombinant Swinepox Virus for Veterinary Vaccine Development.

    Science.gov (United States)

    Fan, Hong-Jie; Lin, Hui-Xing

    2016-01-01

    Poxvirus-vectors have been widely used in vaccine development for several important human and animal diseases; some of these vaccines have been licensed and used extensively. Swinepox virus (SPV) is well suited to develop recombinant vaccines because of its large packaging capacity for recombinant DNA, its host range specificity, and its ability to induce appropriate immune responses. PMID:26458836

  10. 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.

  11. Molecular requirements for radiation-activated recombination

    International Nuclear Information System (INIS)

    Purpose/Objective: The major stumbling block to successful gene therapy today is poor gene transfer. We hypothesized that ionizing radiation might activate cellular recombination, and so improve stable gene transfer. We further hypothesized that known DNA-damage-repair proteins might also be important in radiation-activated recombination. Materials and Methods: The effect of irradiation on stable gene transfer efficiency was determined in human (A549 and 39F) and rodent (NIH/3T3) cell lines. Continuous low dose rate and multiple radiation fractions were also tested. Nuclear extracts were made and the effect of irradiation on inter-plasmid recombination/ligation determined. Multiple DNA damage-repair deficient cell lines were tested for radiation-activated recombination. Results: A significant radiation dose-dependent improvement in stable plasmid transfection (by as much as 1300 fold) is demonstrated in neoplastic and primary cells. An improvement in transient plasmid transfection is also seen, with as much as 85% of cells transiently expressing b-galactosidase (20-50 fold improvement). Stable transfection is only improved for linearized or nicked plasmids. Cells have improved gene transfer for at least 96 hours after irradiation. Both fractionated and continuous low dose rate irradiation are effective at improving stable gene transfer in mammalian cells, thus making relatively high radiation dose delivery clinically feasible. Inter-plasmid recombination is radiation dose dependent in nuclear extract assays, and the type of overhang (3', 5' or blunt end) significantly affects recombination efficiency and the type of product. The most common end-joining activity involves filling-in of the overhang followed by blunt end ligation. Adenovirus is a linear, double stranded DNA virus. We demonstrate that adenoviral infection efficiency is increased by irradiation. The duration of transgene expression is lengthened because the virus integrates with high efficiency (∼10

  12. 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.

  13. Close-coupling R-matrix calculations for electron-ion recombination cross sections

    International Nuclear Information System (INIS)

    Close-coupling (CC) calculations of electron-ion recombination cross sections using the R-matrix method are presented and benchmarked with available experimental measurements. The electron-ion recombination process, including resonant and non-resonant recombination may be unified as a natural extension of the coupled-channel approximation, as traditionally employed for photoionization and electron-ion scattering. Recombination cross sections can be calculated to the same accuracy by employing similar eigenfunction expansions for the target ion. Detailed results are obtained for electron recombination with C V, C VI, O VIII and Fe XXV. Several sets of theoretical calculations are reported and discussed: non-relativistic CC in LS coupling, relativistic CC in the Breit-Pauli approximation, with radiative attenuation and fine structure, and the relativistic distorted-wave approximation. The theoretical results are in very good agreement with highly accurate experimental measurements at the Heidelberg test storage ring for C V, C VI and O VIII, and the electron-ion beam trap at Livermore for Fe XXV. We discuss the overall effect of radiation damping of all resonances on effective cross sections and rates, important for H- and He-like ions. In addition to agreement with experimental data, the validity of the CC calculations is demonstrated by the continuity between the calculated photorecombination, dielectronic recombination and electron impact excitation cross sections. Certain issues related to the works of Badnell et al (1998 J. Phys. B: At. Mol. Opt. Phys. 31 L239) and Robicheaux (1998 J. Phys. B: At. Mol. Opt. Phys. 31 L109) are also addressed. (author)

  14. Attenuation caused by infrequently updated covariates in survival analysis

    DEFF Research Database (Denmark)

    Andersen, Per Kragh; Liestøl, Knut

    Attenuation; Cox regression model; Measurement errors; Survival analysis; Time-dependent covariates......Attenuation; Cox regression model; Measurement errors; Survival analysis; Time-dependent covariates...

  15. V(D)J recombination deficiencies.

    Science.gov (United States)

    de Villartay, Jean-Pierre

    2009-01-01

    V(D)J recombination not only comprises the molecular mechanism that insures diversity of the immune system but also constitutes a critical checkpoint in the developmental program of B- and T-lymphocytes. The analysis of human patients with Severe Combined Immune Deficiency (SCID) has contributed to the understanding of the biochemistry of the V(D)J recombination reaction. The molecular study V(D)J recombination settings in humans, mice and in cellular mutants has allowed to unravel the process of Non Homologous End Joining (NHEJ), one of the key pathway that insure proper repair of DNA double strand breaks (dsb), whether they occur during V(D)J recombination or secondary to other DNA injuries. Two NHEJ factors, Artemis and Cernunnos, were indeed discovered through the study of human V(D)J recombination defective human SCID patients. PMID:19731800

  16. Stress analysis of passive hydrogen autocatalytic recombiner

    International Nuclear Information System (INIS)

    Background: Passive hydrogen autocatalytic recombiner is a device for eliminating hydrogen in the containment of the nuclear power plant when severe accident occurs, avoiding hydrogen explosion. After the Fukushima nuclear accident, the nuclear power plants pay more attention to the role of Passive hydrogen autocatalytic recombiner. Purpose: This paper studies the stresses of passive hydrogen autocatalytic recombiner under the seismic and LOCA conditions, Methods: Modeling by using the finite element software ANSYS, the impacts of airflow load under the LOCA conditions are considered reasonably and the strength of passive hydrogen autocatalytic recombiner is also evaluated according RCC-M, Results: The results show that the model can meet the requirement of the standard document. Conclusions: This paper will provide technical support for stress analysis and evaluation of passive hydrogen autocatalytic recombiner. (authors)

  17. Genome sequence of SG33 strain and recombination between wild-type and vaccine myxoma viruses.

    Science.gov (United States)

    Camus-Bouclainville, Christelle; Gretillat, Magalie; Py, Robert; Gelfi, Jacqueline; Guérin, Jean Luc; Bertagnoli, Stéphane

    2011-04-01

    Myxomatosis in Europe is the result of the release of a South America strain of myxoma virus in 1952. Several attenuated strains with origins in South America or California have since been used as vaccines in the rabbit industry. We sequenced the genome of the SG33 myxoma virus vaccine strain and compared it with those of other myxoma virus strains. We show that SG33 genome carries a large deletion in its right end. Furthermore, our data strongly suggest that the virus isolate from which SG33 is derived results from an in vivo recombination between a wild-type South America (Lausanne) strain and a California MSD-derived strain. These findings raise questions about the use of insufficiently attenuated virus in vaccination. PMID:21470452

  18. Containment air circulation for optimal hydrogen recombination

    International Nuclear Information System (INIS)

    An accepted first-line defense for hydrogen mitigation is to design for the hydrogen to be rapidly mixed with the containment atmosphere and diluted to below flammability concentrations. Then, as hydrogen continues to be produced in the longer term, recombiners can be used to remove hydrogen: recombiners can be located in forced-air ducts or passive recombiners can be distributed within containment and the heat of recombination used to promote local air circulation. However, this principle does not eliminate the possibility of high hydrogen concentrations at locations removed from the recombiners. An improvement on this strategy is to arrange for a specific, buoyancy-driven, overall circulation of the containment atmosphere such that the recombiners can be located within the recirculation flow, immediately downstream of the hydrogen source. This would make the mixing process more predictable and solve the mass-transfer problem associated with distributed recombiners. Ideally, the recombiners would be located just above the hydrogen source so that the heat of recombination would assist the overall circulation. In this way, the hydrogen would be removed as close as possible to the source, thereby minimizing the amount of hydrogen immediately downstream of the source and reducing the hydrogen concentration to acceptable levels at other locations. Such a strategy requires the containment volume to be divided into an upflow path, past the hydrogen source and the recombiner, and a downflow path to complete the circuit. The flow could be generated actively using fans or passively using buoyancy forces arising from the difference in density of gases in the upfiow and downflow paths; the gases in the downflow path being cooled at an elevated heat sink. (author)

  19. A novel recombinant multi-epitope protein against Brucella melitensis infection.

    Science.gov (United States)

    Yin, Dehui; Li, Li; Song, Dandan; Liu, Yushen; Ju, Wen; Song, Xiuling; Wang, Juan; Pang, Bo; Xu, Kun; Li, Juan

    2016-07-01

    Live, attenuated Brucella vaccines are considered effective but can induce abortions in pregnant animals and are potentially infectious to humans. There is a strong need to improve the immunoprotective effects and safety of vaccines against Brucella. Currently, subunit vaccines have been demonstrated to be safe and efficacious alternatives in both humans and animals. In this study, we employed bioinformatics tools to predict B and T cell epitopes to aid development of a novel recombinant multi-epitope antigen for brucellosis vaccination. To evaluate the protective capacity of the recombinant antigen, the antigen's efficacy was studied in a mouse model of brucellosis. Our results indicated that BALB/c mice immunized with this recombinant multi-epitope antigen showed mixed Th1-Th2 immune responses with high levels of specific IgG and exhibited high degrees of IFN-γ and IL-6 and significantly higher CD3, CD4, and CD8 frequencies compared to the control group. The recombinant antigen and vaccine strain M5-90 also provided protection against Brucella melitensis 16 M infection. Using bioinformatics tools to develop candidate vaccines is a promising strategy for the development of Brucella vaccines. PMID:27133932

  20. 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.

  1. Radiation-attenuated vaccine for lungworm disease

    International Nuclear Information System (INIS)

    The work done at the Indian Veternary Research Institute, Izatnagar, on the development of a vaccine for lungworm diseases is reported. Research work done includes: (1) studies on the epidemiology and the incidence of the lungworm infections, (ii) studies on the radiation-attenuated lungworm Dictyocaulus filaria vaccine, (iii) studies on other parasites using ionizing radiation, (iv) incidence of lungworm infection in sheep in Jammu and Kashmir State, (v) suitable dose of gamma radiation for attenuation, (vi) laboratory studies with radiation-attenuated D. filaria vaccine, (vii) serology of D. filaria infection, (viii) field trials with the radiation-attenuated vaccine, (ix) immune response of previously exposed lambs to vaccination, (x) comparative susceptibility of sheep and goats to infection with D. filaria, (xi) quantitative studies of D. filaria in lambs and (xii) production and supply of lungworm vaccine. (A.K.)

  2. Attenuation layer for magnetostatic wave (MSW) absorbers

    Science.gov (United States)

    Glass, H. L.; Adkins, L. R.; Stearns, F. S.

    1984-09-01

    A new technique has been developed for the suppression of MSW end reflections which give rise to passband ripple. The basic idea is to provide a thin film of highly attenuating epitaxial material at the ends of a MSW delay line while preserving high quality YIG in the active region of the device. The GGG wafer preparation is a three step process which involves: (1) the growth of the attenuation layer, (2) the removal of this layer from the central region of the wafer and (3) the growth of high quality YIG on the remaining structure. Delay lines using the attenuation layer for end terminations have been evaluated experimentally and compared to devices utilizing other termination methods. The results indicate that the attenuation layer method produces ripple suppression characteristics which are the equal of those obtained with other termination techniques. The advantage of this new method lies in its suitability for large quantity fabrication requirements.

  3. Post-Retrieval Extinction Attenuates Cocaine Memories

    OpenAIRE

    Sartor, Gregory C.; Aston-Jones, Gary

    2013-01-01

    Recent studies have shown that post-retrieval extinction training attenuates fear and reward-related memories in both humans and rodents. This noninvasive, behavioral approach has the potential to be used in clinical settings to treat maladaptive memories that underlie several psychiatric disorders, including drug addiction. However, few studies to date have used a post-retrieval extinction approach to attenuate addiction-related memories. In the current study, we attempted to disrupt cocaine...

  4. Brucellosis: The Case for Live, Attenuated Vaccines

    OpenAIRE

    Ficht, Thomas A.; Kahl-McDonagh, Melissa M.; Arenas-Gamboa, Angela M.; Rice-Ficht, Allison C.

    2009-01-01

    The successful control of animal brucellosis and associated reduction in human exposure has limited the development of human brucellosis vaccines. However, the potential use of Brucella in bioterrorism or biowarfare suggests that direct intervention strategies are warranted. Although the dominant approach has explored the use of live attenuated vaccines, side-effects associated with their use has prevented widespread use in humans. Development of live, attenuated Brucella vaccines that are sa...

  5. Investigation of photon attenuation coefficients for marble

    International Nuclear Information System (INIS)

    The total linear attenuation coefficients μ (cm-1) have been obtained using the XCOM program at photon energies of 1 keV to 1 GeV for six different natural marbles produced in different places in Turkey. The individual contribution of photon interaction processes to the total linear attenuation coefficients for marble has been investigated. The calculated results were also compared with the measurements. The results obtained for marble were also compared with concrete. (note)

  6. Electron Effective-Attenuation-Length Database

    Science.gov (United States)

    SRD 82 NIST Electron Effective-Attenuation-Length Database (PC database, no charge)   This database provides values of electron effective attenuation lengths (EALs) in solid elements and compounds at selected electron energies between 50 eV and 2,000 eV. The database was designed mainly to provide EALs (to account for effects of elastic-eletron scattering) for applications in surface analysis by Auger-electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS).

  7. 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....

  8. Hepatitis C virus core protein enhances hepatocellular carcinoma cells to be susceptible to oncolytic vesicular stomatitis virus through down-regulation of HDAC4.

    Science.gov (United States)

    Moon, Jeong; Kaowinn, Sirichat; Cho, Il-Rae; Min, Do Sik; Myung, Heejoon; Oh, Sangtaek; Kaewpiboon, Chutima; Kraemer, Olive H; Chung, Young-Hwa

    2016-06-01

    Since hepatitis C virus (HCV) core protein is known to possess potential oncogenic activity, we explored whether oncolytic vesicular stomatitis virus (VSV) could efficiently induce cytolysis in hepatocellular carcinoma cells stably expressing HCV core protein (Hep3B-Core). We found that Hep3B-Core cells were more susceptible to VSV as compared to control (Hep3B-Vec) cells owing to core-mediated inactivation of STAT1 and STAT2 proteins. Core expression induced lower phosphorylation levels of type I IFN signaling proteins such as Tyk2 and Jak1, and a reduced response to exogenous IFN-α, which resulted in susceptibility to VSV. Furthermore, as STAT1 acetylation by switching phosphorylation regulated its activity, the role of STAT1 acetylation in susceptibility of Hep3B-Core cells to VSV was investigated. Treatment with trichostatin A, an inhibitor of histone deacetylase (HDAC), increased STAT1 acetylation but blocked IFN-α-induced phosphorylation of STAT1, leading to increase of susceptibility to VSV. Interestingly, the core protein decreased HDCA4 transcript levels, leading to down-regulation of HDAC4 protein. However, ectopic expression of HDAC4 conversely enforced phosphorylation of STAT1 and hindered VSV replication, indicating that core-mediated reduction of HDAC4 provides a suitable intracellular circumstance for VSV replication. Collectively, we suggest that VSV treatment will be a useful therapeutic strategy for HCV-infected hepatocellular carcinoma cells because HCV core protein suppresses the anti-viral threshold by down-regulation of the STAT1-HDAC4 signaling axis. PMID:27150631

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

    International Nuclear Information System (INIS)

    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

  10. 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.

  11. Cdk1 targets Srs2 to complete synthesis-dependent strand annealing and to promote recombinational repair.

    Directory of Open Access Journals (Sweden)

    Marco Saponaro

    2010-02-01

    Full Text Available Cdk1 kinase phosphorylates budding yeast Srs2, a member of UvrD protein family, displays both DNA translocation and DNA unwinding activities in vitro. Srs2 prevents homologous recombination by dismantling Rad51 filaments and is also required for double-strand break (DSB repair. Here we examine the biological significance of Cdk1-dependent phosphorylation of Srs2, using mutants that constitutively express the phosphorylated or unphosphorylated protein isoforms. We found that Cdk1 targets Srs2 to repair DSB and, in particular, to complete synthesis-dependent strand annealing, likely controlling the disassembly of a D-loop intermediate. Cdk1-dependent phosphorylation controls turnover of Srs2 at the invading strand; and, in absence of this modification, the turnover of Rad51 is not affected. Further analysis of the recombination phenotypes of the srs2 phospho-mutants showed that Srs2 phosphorylation is not required for the removal of toxic Rad51 nucleofilaments, although it is essential for cell survival, when DNA breaks are channeled into homologous recombinational repair. Cdk1-targeted Srs2 displays a PCNA-independent role and appears to have an attenuated ability to inhibit recombination. Finally, the recombination defects of unphosphorylatable Srs2 are primarily due to unscheduled accumulation of the Srs2 protein in a sumoylated form. Thus, the Srs2 anti-recombination function in removing toxic Rad51 filaments is genetically separable from its role in promoting recombinational repair, which depends exclusively on Cdk1-dependent phosphorylation. We suggest that Cdk1 kinase counteracts unscheduled sumoylation of Srs2 and targets Srs2 to dismantle specific DNA structures, such as the D-loops, in a helicase-dependent manner during homologous recombinational repair.

  12. Cdk1 targets Srs2 to complete synthesis-dependent strand annealing and to promote recombinational repair.

    Science.gov (United States)

    Saponaro, Marco; Callahan, Devon; Zheng, Xiuzhong; Krejci, Lumir; Haber, James E; Klein, Hannah L; Liberi, Giordano

    2010-02-01

    Cdk1 kinase phosphorylates budding yeast Srs2, a member of UvrD protein family, displays both DNA translocation and DNA unwinding activities in vitro. Srs2 prevents homologous recombination by dismantling Rad51 filaments and is also required for double-strand break (DSB) repair. Here we examine the biological significance of Cdk1-dependent phosphorylation of Srs2, using mutants that constitutively express the phosphorylated or unphosphorylated protein isoforms. We found that Cdk1 targets Srs2 to repair DSB and, in particular, to complete synthesis-dependent strand annealing, likely controlling the disassembly of a D-loop intermediate. Cdk1-dependent phosphorylation controls turnover of Srs2 at the invading strand; and, in absence of this modification, the turnover of Rad51 is not affected. Further analysis of the recombination phenotypes of the srs2 phospho-mutants showed that Srs2 phosphorylation is not required for the removal of toxic Rad51 nucleofilaments, although it is essential for cell survival, when DNA breaks are channeled into homologous recombinational repair. Cdk1-targeted Srs2 displays a PCNA-independent role and appears to have an attenuated ability to inhibit recombination. Finally, the recombination defects of unphosphorylatable Srs2 are primarily due to unscheduled accumulation of the Srs2 protein in a sumoylated form. Thus, the Srs2 anti-recombination function in removing toxic Rad51 filaments is genetically separable from its role in promoting recombinational repair, which depends exclusively on Cdk1-dependent phosphorylation. We suggest that Cdk1 kinase counteracts unscheduled sumoylation of Srs2 and targets Srs2 to dismantle specific DNA structures, such as the D-loops, in a helicase-dependent manner during homologous recombinational repair. PMID:20195513

  13. 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. 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.

  2. 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.

  3. 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....... 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....

  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. 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...... 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......, 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....

  6. Fat Attenuation at CT in Anorexia Nervosa.

    Science.gov (United States)

    Gill, Corey M; Torriani, Martin; Murphy, Rachel; Harris, Tamara B; Miller, Karen K; Klibanski, Anne; Bredella, Miriam A

    2016-04-01

    Purpose To investigate the composition, cross-sectional area (CSA), and hormonal correlates of different fat depots in women with anorexia nervosa (AN) and control subjects with normal weights to find out whether patients with AN have lower fat CSA but higher attenuation than did control subjects and whether these changes may be mediated by gonadal steroids, cortisol, and thyroid hormones. Materials and Methods This study was institutional review board approved and HIPAA compliant. Written informed consent was obtained. Forty premenopausal women with AN and 40 normal-weight women of comparable age (mean age ± standard deviation, 26 years ± 5) were studied. All individuals underwent computed tomography of the abdomen and thigh with a calibration phantom. Abdominal subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), thigh SAT, and thigh intermuscular adipose tissue CSA and attenuation were quantified. Serum estradiol, thyroid hormones, and urinary free cortisol levels were assessed. Variables were compared by using analysis of variance. Associations were examined by using linear regression analysis. Results Women with AN had higher fat attenuation than did control subjects (-100.1 to -46.7 HU vs -117.6 to -61.8 HU, P < .0001), despite lower fat CSA (2.0-62.8 cm(2) vs 5.5-185.9 cm(2), P < .0001). VAT attenuation but not CSA was inversely associated with lowest prior lifetime body mass index in AN (r = -0.71, P = .006). Serum estradiol levels were inversely associated with fat attenuation (r = -0.34 to -0.61, P = .03 to <.0001) and were positively associated with fat CSA of all compartments (r = 0.42-0.64, P = .007 to <.0001). Thyroxine levels and urinary free cortisol levels were positively associated with thigh SAT attenuation (r = 0.64 [P = .006] and r = 0.68 [P = .0004], respectively) and were inversely associated with abdominal SAT and VAT CSA (r = -0.44 to -0.58, P = .04 to .02). Conclusion Women with AN have differences in fat composition, with

  7. Efficient generation of recombinant adenoviral vectors by Cre-lox recombination in vitro.

    OpenAIRE

    Aoki, K.; Barker, C.; Danthinne, X; Imperiale, M J; Nabel, G. J.

    1999-01-01

    BACKGROUND: Although recombinant adenovirus vectors are attractive for use in gene expression studies and therapeutic applications, the construction of these vectors remains relatively time-consuming. We report here a strategy that simplifies the production of adenoviruses using the Cre-loxP system. MATERIALS AND METHODS: Full-length recombinant adenovirus DNA was generated in vitro by Cre-mediated recombination between loxP sites in a linearized shuttle plasmid containing a transgene and ade...

  8. Intermolecular recombination assay for mammalian cells that produces recombinants carrying both homologous and nonhomologous junctions.

    OpenAIRE

    Brouillette, S; Chartrand, P

    1987-01-01

    We present an intermolecular recombination assay for mammalian cells that does not involve the reconstitution of a selectable marker. It is based on the generation of a shuttle vector by recombination between a bacterial and a mammalian vector. The recombinants can thus be amplified in mammalian cells, isolated by plasmid rescue in an Escherichia coli RecA- host, and identified by in situ hybridization, by using mammalian vector sequences as probes. Since both parental molecules can share def...

  9. Cine CT for Attenuation Correction in Cardiac PET/CT

    OpenAIRE

    Alessio, Adam M.; Kohlmyer, Steve; Branch, Kelley; Chen, Grace; Caldwell, James; Kinahan, Paul

    2007-01-01

    In dual-modality PET/CT systems, the CT scan provides the attenuation map for PET attenuation correction. The current clinical practice of obtaining a single helical CT scan provides only a snapshot of the respiratory cycle, whereas PET occurs over multiple respiratory cycles. Misalignment of the attenuation map and emission image because of respiratory motion causes errors in the attenuation correction factors and artifacts in the attenuation-corrected PET image. To rectify this problem, we ...

  10. Signals From the Epoch of Cosmological Recombination

    OpenAIRE

    Sunyaev, R. A.; Chluba, J.

    2009-01-01

    The physical ingredients to describe the epoch of cosmological recombination are amazingly simple and well-understood. This fact allows us to take into account a very large variety of physical processes, still finding potentially measurable consequences for the energy spectrum and temperature anisotropies of the Cosmic Microwave Background (CMB). In this contribution we provide a short historical overview in connection with the cosmological recombination epoch and its connection to the CMB. A...

  11. Tunnel surface recombination in optoelectronic device modeling

    Science.gov (United States)

    Ptashchenko, Alexander A.; Ptashchenko, Fedor A.

    1997-08-01

    The rate of tunnel surface recombination (TSR) in a p-n structure has been calculated as a function of the excitation level and temperature in a semiclassical approximation under the assumption that the excess energy of a recombining electron is transferred to phonons or to a photon. The approximating analytical expressions obtained are applied in calculations of the effect of TSR on the characteristics of photodiodes, solar cells, light-emitting diodes and diode lasers.

  12. Recombinant DNA production of spider silk proteins

    OpenAIRE

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

    2013-01-01

    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...

  13. Algae-based oral recombinant vaccines

    OpenAIRE

    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 ...

  14. Dielectronic recombination of hydrogen-like ions

    International Nuclear Information System (INIS)

    Decay dynamics of dielectronic recombination (DR) processes of H-like titanium ions was investigated with an electron beam ion trap. In the DR of H-like ions a K-shell vacancy is available even after the decay of the doubly excited state produced by the recombination. Therefore secondary X-ray emission is possible. An observed X-ray spectrum of DR obtained in the present experiment was well reproduced theoretically by taking into account the secondary X-rays

  15. Recombination-deficient mutant of Streptococcus faecalis.

    OpenAIRE

    Yagi, Y; Clewell, D B

    1980-01-01

    An ultraviolet radiation-sensitive derivative of Streptococcus faecalis strain JH2-2 was isolated and found to be deficient in recombination, using a plasmid-plasmid recombination system. The strain was sensitive to chemical agents which interact with deoxyribonucleic acid and also underwent deoxyribonucleic acid degradation after ultraviolet irradiation. Thus, the mutant has properties similar to those of recA strains of Escherichia coli.

  16. Enabling photon counting detectors with dynamic attenuators

    Science.gov (United States)

    Hsieh, Scott S.; Pelc, Norbert J.

    2014-03-01

    Photon-counting x-ray detectors (PCXDs) are being investigated as a replacement for conventional x-ray detectors because they promise several advantages, including better dose efficiency, higher resolution and spectral imaging. However, many of these advantages disappear when the x-ray flux incident on the detector is too high. We recently proposed a dynamic, piecewise-linear attenuator (or beam shaping filter) that can control the flux incident on the detector. This can restrict the operating range of the PCXD to keep the incident count rate below a given limit. We simulated a system with the piecewise-linear attenuator and a PCXD using raw data generated from forward projected DICOM files. We investigated the classic paralyzable and nonparalyzable PCXD as well as a weighted average of the two, with the weights chosen to mimic an existing PCXD (Taguchi et al, Med Phys 2011). The dynamic attenuator has small synergistic benefits with the nonparalyzable detector and large synergistic benefits with the paralyzable detector. Real PCXDs operate somewhere between these models, and the weighted average model still shows large benefits from the dynamic attenuator. We conclude that dynamic attenuators can reduce the count rate performance necessary for adopting PCXDs.

  17. Recombination of U92+ ions with electrons

    International Nuclear Information System (INIS)

    Recombination of fully stripped U92+ ions with electrons has been investigated at the Experimental Storage Ring (ESR) in Darmstadt. Absolute recombination rate coefficients have been measured for relative energies from 0 to 33 eV. For energies greater than 20 meV the experimental result is well described by the theory for radiative recombination (RR). Below 20 meV the experimental rate increasingly exceeds the RR calculation as observed previously in the recombination of light bare ions as well as of Bi83+. This low-energy rate enhancement is shown to scale as Z2.6 for bare ions, where Z is the atomic number of the ion. The U92+ recombination rate enhancement is insensitive to changes of the electron density. Variation of the magnetic guiding field strength from 80 mT to 120 mT resulted in oscillations of the recombination rate at 0 eV. The oscillations are partly attributed to changes of the transverse electron temperature accompanying the change of the magnetic guiding field strength; partly they may be caused by uncompensated small changes of the interaction angle between the two beams. (orig.)

  18. Development of a multiplex RT-PCR assay for the identification of recombination types at different genomic regions of vaccine-derived polioviruses.

    Science.gov (United States)

    Dimitriou, T G; Kyriakopoulou, Z; Tsakogiannis, D; Fikatas, A; Gartzonika, C; Levidiotou-Stefanou, S; Markoulatos, P

    2016-08-01

    Polioviruses (PVs) are the causal agents of acute paralytic poliomyelitis. Since the 1960s, poliomyelitis has been effectively controlled by the use of two vaccines containing all three serotypes of PVs, the inactivated poliovirus vaccine and the live attenuated oral poliovirus vaccine (OPV). Despite the success of OPV in polio eradication programme, a significant disadvantage was revealed: the emergence of vaccine-associated paralytic poliomyelitis (VAPP). VAPP is the result of accumulated mutations and putative recombination events located at the genome of attenuated vaccine Sabin strains. In the present study, ten Sabin isolates derived from OPV vaccinees and environmental samples were studied in order to identify recombination types located from VP1 to 3D genomic regions of virus genome. The experimental procedure that was followed was virus RNA extraction, reverse transcription to convert the virus genome into cDNA, PCR and multiplex-PCR using specific designed primers able to localize and identify each recombination following agarose gel electrophoresis. This multiplex RT-PCR assay allows for the immediate detection and identification of multiple recombination types located at the viral genome of OPV derivatives. After the eradication of wild PVs, the remaining sources of poliovirus infection worldwide would be the OPV derivatives. As a consequence, the immediate detection and molecular characterization of recombinant derivatives are important to avoid epidemics due to the circulation of neurovirulent viral strains. PMID:27098645

  19. Estimation of Charge Exchange Recombination Emission Based on Diagnostic Neutral Beam on the Experimental Advanced Superconducting Tokamak

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xian-Mei; WAN Bao-Nian; WU Zhen-Wei

    2007-01-01

    Diagnostic neutral beam (DNB) attenuation and charge exchange recombination emission are estimated on EAST tokamak. Approximately 40% of the beam with the energy of 50 keV can reach the plasma centre (r = 0) for the typical parameters of the Experimental Advanced Superconducting Tokamak (EAST) plasma. Emissivities of CVI (n = 8 → 7, 529.0nm) and OVⅢ (n = 10 → 9, 607.0 nm) visible charge exchange recombination emissions based on the DNB are estimated. The emissivities of the visible bremsstrahlung emission near this wavelength are also calculated for comparison. The results show that the charge exchange recombination emission is about two orders of magnitude greater than the bremsstrahlung emission. It is theoretically indicated that the ratio of signal of charge exchange recombination spectroscopy to the noise from background bremsstrahlung emission,S/N, is large enough in the EAST tokamak with the typical designed parameters. The present results are helpful for experiment design of charge-exchange recombination spectroscopy based on the DNB in the EAST tokamak.

  20. Protection against infectious laryngotracheitis by in ovo vaccination with commercially available viral vector recombinant vaccines.

    Science.gov (United States)

    Johnson, Deirdre I; Vagnozzi, Ariel; Dorea, Fernanda; Riblet, Sylva M; Mundt, Alice; Zavala, Guillermo; García, Maricarmen

    2010-12-01

    Infectious laryngotracheitis (ILT) is a highly contagious respiratory disease of chickens caused by infectious laryngotracheitis virus (ILTV). The disease is mainly controlled through biosecurity and by vaccination with live-attenuated vaccines. The chicken embryo origin (CEO) vaccines, although proven to be effective in experimental settings, have limited efficacy in controlling the disease in dense broiler production sites due to unrestricted use and poor mass vaccination coverage. These factors allowed CEO vaccines to regain virulence, causing long lasting and, consequently, severe outbreaks of the disease. A new generation of viral vector fowl poxvirus (FPV) and herpesvirus of turkey (HVT) vaccines carrying ILTV genes has been developed and such vaccines are commercially available. These vaccines are characterized by their lack of transmission, lack of ILTV-associated latent infections, and no reversion to virulence. HVT-vectored ILTV recombinant vaccines were originally approved for subcutaneous HVT or transcutaneous (pox) delivery. The increased incidence of ILTV outbreaks in broiler production sites encouraged the broiler industry to deliver the FPV-LT and HVT-LT recombinant vaccines in ovo. The objective of this study was to evaluate the protection induced by ILTV viral vector recombinant vaccines after in ovo application in 18-day-old commercial broiler embryos. The protection induced by recombinant ILTV vaccines was assessed by their ability to prevent clinical signs and mortality; to reduce challenge virus replication in the trachea; to prevent an increase in body temperature; and to prevent a decrease in body weight gain after challenge. In this study, both recombinant-vectored ILTV vaccines provided partial protection, thereby mitigating the disease, but did not reduce challenge virus loads in the trachea. PMID:21313847

  1. Finite Element Analysis of Honeycomb Impact Attenuator

    Science.gov (United States)

    Yang, Seung-Yong; Choi, Seung-Kyu; Kim, Nohyu

    To participate in Student Formula Society of Automotive Engineers (SAE) competitions, it is necessary to build an impact attenuator that would give an average deceleration not to exceed 20g when it runs into a rigid wall. Students can use numerical simulations or experimental test data to show that their car satisfies this safety requirement. A student group to study formula cars at the Korea University of Technology and Education has designed a vehicle to take part in a SAE competition, and a honeycomb structure was adopted as the impact attenuator. In this paper, finite element calculations were carried out to investigate the dynamic behavior of the honeycomb attenuator. Deceleration and deformation behaviors were studied. Effect of the yield strength was checked by comparing the numerical results. ABAQUS/Explicit finite element code was used.

  2. Attenuation of the gamma rays in tissues

    International Nuclear Information System (INIS)

    The mass and lineal attenuation coefficient and of hepatic tissue, muscular, osseous and of brain before gamma rays of 10-3 to 105 MeV were calculated. For the case of the osseous tissue the calculation was made for the cartilage, the cortical tissue and the bone marrow. During the calculations the elementary composition of the tissues of human origin was used. The calculations include by separate the Photoelectric effect, the Compton scattering and the Pair production, as well as the total. For to establish a comparison with the attenuation capacities, the coefficients of the water, the aluminum and the lead also were calculated. The study was complemented measuring the attenuation coefficient of hepatic tissue of bovine before gamma rays of 0.662 MeV of a source of 137 Cs. The measurement was made through of an experiment of photons transmission through samples frozen of hepatic tissue and with a Geiger-Mueller detector. (Author)

  3. Graphene-Based Waveguide Terahertz Wave Attenuator

    Science.gov (United States)

    Jian-rong, Hu; Jiu-sheng, Li; Guo-hua, Qiu

    2016-07-01

    We design an electrically controllable terahertz wave attenuator by using graphene. We show that terahertz wave can be confined and propagate on S-shaped graphene waveguide with little radiation losses, and the confined terahertz wave is further manipulated and controlled via external applied voltage bias. The simulated results show that, when chemical potential changes from 0.03 into 0.05 eV, the extinction ratio of the terahertz wave attenuator can be tuned from 1.28 to 39.42 dB. Besides the simplicity, this novel terahertz wave attenuator has advantages of small size (24 × 30 μm2), a low insertion loss, and good controllability. It has a potential application for forthcoming planar terahertz wave integrated circuit fields.

  4. Attenuation of ear muffs in Canadian mines

    Energy Technology Data Exchange (ETDEWEB)

    Savich, M.U.

    1979-12-01

    The main characteristics of eleven commercially available ear muffs were investigated in the laboratory and analyzed by a psychophysical and a physical method. Nine ear muffs were tested in mines. The three best muffs had bands passing behind the head. The ear muff with a support strap, which improves comfort and maintains a good fit during wear, showed the best attenuation. Causes of poor attenuation are listed. None of the ear muffs tested had all the characteristics desirable in an ideal unit. Because of unsatisfactory attenuation in working conditions, it should be a mandatory requirement that workers wear both ear muffs and ear plugs if the noise level is higher than 105 dBA.

  5. Extensible chip of optofluidic variable optical attenuator.

    Science.gov (United States)

    Wan, J; Xue, F L; Wu, L X; Fu, Y J; Hu, J; Zhang, W; Hu, F R

    2016-05-01

    A core chip of optofluidic variable optical attenuator (VOA) is reported. The chip, with a simple structure, utilizes microfluid and compressed air to regulate the optical attenuation, and it can be expanded to form a number of VOAs by using different microfluidic driving technologies. Three VOAs based on this chip and different driving technologies are introduced. The theoretical and experimental results show that the proposed chip possesses the advantages of large optical attenuation range (> 50dB) and low insertion loss (0.55 dB). Moreover it is a broadband optical device which can be operated in visible and near infrared wavelengths. The proposed chip provides a new method for seeking miniaturized VOAs with good performances, and it is promising to develop a number of different VOAs. PMID:27137582

  6. Research on Nanosecond Pulse Corona Discharge Attenuation

    International Nuclear Information System (INIS)

    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

  7. 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.

  8. Study of neutral beam attenuation of 5 MW hydrogen beam in SST-1 Tokomak

    International Nuclear Information System (INIS)

    The neutral beam injector (NBI) system at IPR is capable of injecting ∼1 MW of neutral beam (H°, 30-50 keV) power to the Tokamak (SST-1) plasma for performing heating and current drive experiments. Currently, preparations are underway for integrating the NBI injector with the SST-1 Tokamak. For understanding the power transmission into the tokomak and power delivered to the NB shine-through, knowledge on the neutral beam attenuation profile for different impurity composition and in various operating scenarios of SST-1 operation is necessary. A comprehensive Charge Exchange Recombination and Beam emission analysis package is being developed under JET-IPR collaboration, for analysing the CX and Beam emissions from Tokamaks. A neutral beam attenuation package for SST-1 is being developed to suit the SST-1 NBI geometries and plasma, which is expected to have Carbon and Oxygen as the main impurity species. The main features of the package and the computed neutral beam attenuation profiles, for various operation scenarios of SST1 have been presented here

  9. 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.

  10. 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.

  11. 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

  12. 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

  13. Preclinical pharmacology and toxicology study of Ad-hTERT-E1a-Apoptin, a novel dual cancer-specific oncolytic adenovirus

    International Nuclear Information System (INIS)

    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 × 108, 2.5 × 109, and 1.25 × 1010 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 × 108, 2.5 × 109, and 1.25 × 1010 VP/kg doses. In acute toxicity tests in mice, the maximum tolerated dose > 5 × 1010 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 × 1010 VP/kg) and beagles (2.5 × 109 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 × 1010 VP/mL Ad-hTERT-E1a-Apoptin each and challenged by one intravenous injection of 1.67 × 108 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-hTERT-E1a-Apoptin

  14. Performance testing of passive autocatalytic recombiners (PARs)

    International Nuclear Information System (INIS)

    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)

  15. 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.

  16. Live Attenuated Influenza Vaccine Provides Superior Protection from Heterologous Infection in Pigs with Maternal Antibodies without Inducing Vaccine-Associated Enhanced Respiratory Disease

    OpenAIRE

    Vincent, Amy L.; Ma, Wenjun; Lager, Kelly M.; Richt, Jürgen A.; Janke, Bruce H.; Sandbulte, Matthew R.; Gauger, Philip C.; Loving, Crystal L.; Webby, Richard J; García-Sastre, Adolfo

    2012-01-01

    Control of swine influenza A virus (IAV) in the United States is hindered because inactivated vaccines do not provide robust cross-protection against the multiple antigenic variants cocirculating in the field. Vaccine efficacy can be limited further for vaccines administered to young pigs that possess maternally derived immunity. We previously demonstrated that a recombinant A/sw/Texas/4199-2/1998 (TX98) (H3N2) virus expressing a truncated NS1 protein is attenuated in swine and has potential ...

  17. 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

  18. 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.

  19. Human recombinant lysosomal enzymes produced in microorganisms.

    Science.gov (United States)

    Espejo-Mojica, Ángela J; Alméciga-Díaz, Carlos J; Rodríguez, Alexander; Mosquera, Ángela; Díaz, Dennis; Beltrán, Laura; Díaz, Sergio; Pimentel, Natalia; Moreno, Jefferson; Sánchez, Jhonnathan; Sánchez, Oscar F; Córdoba, Henry; Poutou-Piñales, Raúl A; Barrera, Luis A

    2015-01-01

    Lysosomal storage diseases (LSDs) are caused by accumulation of partially degraded substrates within the lysosome, as a result of a function loss of a lysosomal protein. Recombinant lysosomal proteins are usually produced in mammalian cells, based on their capacity to carry out post-translational modifications similar to those observed in human native proteins. However, during the last years, a growing number of studies have shown the possibility to produce active forms of lysosomal proteins in other expression systems, such as plants and microorganisms. In this paper, we review the production and characterization of human lysosomal proteins, deficient in several LSDs, which have been produced in microorganisms. For this purpose, Escherichia coli, Saccharomyces cerevisiae, Pichia pastoris, Yarrowia lipolytica, and Ogataea minuta have been used as expression systems. The recombinant lysosomal proteins expressed in these hosts have shown similar substrate specificities, and temperature and pH stability profiles to those produced in mammalian cells. In addition, pre-clinical results have shown that recombinant lysosomal enzymes produced in microorganisms can be taken-up by cells and reduce the substrate accumulated within the lysosome. Recently, metabolic engineering in yeasts has allowed the production of lysosomal enzymes with tailored N-glycosylations, while progresses in E. coli N-glycosylations offer a potential platform to improve the production of these recombinant lysosomal enzymes. In summary, microorganisms represent convenient platform for the production of recombinant lysosomal proteins for biochemical and physicochemical characterization, as well as for the development of ERT for LSD. PMID:26071627

  20. Growth properties and vaccine efficacy of recombinant pseudorabies virus defective in glycoprotein E and thymidine kinase genes.

    Science.gov (United States)

    Wu, Ching-Ying; Liao, Chih-Ming; Chi, Jiun-Ni; Chien, Maw-Sheng; Huang, Chienjin

    2016-07-10

    Pseudorabies virus (PRV) is an alphaherpesvirus that causes pseudorabies (PR), an economically important viral disease of pigs. Marker vaccines were widely used in PR prevention and eradication programs. The purpose of this study was to construct a novel recombinant virus with deletions at defined regions in the glycoprotein E (gE) and thymine kinase (TK) genes by homologous recombination. This study also evaluated the safety and efficacy of the virus for a live attenuated marker vaccine. No significant difference was observed in virus replication between gE gene-deleted (gE(-)), gE/TK double gene-deleted (gE(-)TK(-)), and wild-type PRV by growth curve analysis. However, gE(-)TK(-) PRV was completely attenuated in mice. To evaluate the immunogenicity of gE(-)TK(-) PRV, four 12-week-old specific-pathogen-free pigs per group were immunized intramuscularly with viral titers of 1×10(4), 1×10(5), or 1×10(6) TCID50, followed by intranasal challenge infection with virulent PRV (1×10(8) TCID50) at 3 weeks post vaccination. The gE(-)TK(-) PRV-vaccinated pigs displayed no general adverse effects after immunization and had protective immune responses after PRV challenge. Thus, gE(-)TK(-) PRV was safe and efficacious and might be a potential candidate for a live attenuated marker vaccine against PRV. PMID:27164258

  1. Hadron attenuation at HERMES and JLab

    OpenAIRE

    Falter, T.; Cassing, W.; Gallmeister, K.; Mosel, U.

    2005-01-01

    We investigate the attenuation of hadrons in deep inelastic lepton-nucleus scattering in the kinematical regime of the HERMES and Jefferson Lab experiments. The calculation is carried out in the framework of a BUU transport model. Our results indicate a strong influence of (pre)hadronic final state interactions on the observed multiplicity ratios.

  2. 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.

  3. Switching Control for Adaptive Disturbance Attenuation

    NARCIS (Netherlands)

    Battistelli, Giorgio; Mari, Daniele; Selvi, Daniela; Tesi, Alberto; Tesi, Pietro

    2014-01-01

    The problem of adaptive disturbance attenuation is addressed in this paper using a switching control approach. A finite family of stabilizing controllers is pre-designed, with the assumption that, for any possible operating condition, at least one controller is able to achieve a prescribed level of

  4. Attenuation correction for small animal PET tomographs

    Energy Technology Data Exchange (ETDEWEB)

    Chow, Patrick L [David Geffen School of Medicine at UCLA, Crump Institute for Molecular Imaging, University of California, 700 Westwood Plaza, Los Angeles, CA 90095 (United States); Rannou, Fernando R [Departamento de Ingenieria Informatica, Universidad de Santiago de Chile (USACH), Av. Ecuador 3659, Santiago (Chile); Chatziioannou, Arion F [David Geffen School of Medicine at UCLA, Crump Institute for Molecular Imaging, University of California, 700 Westwood Plaza, Los Angeles, CA 90095 (United States)

    2005-04-21

    Attenuation correction is one of the important corrections required for quantitative positron emission tomography (PET). This work will compare the quantitative accuracy of attenuation correction using a simple global scale factor with traditional transmission-based methods acquired either with a small animal PET or a small animal x-ray computed tomography (CT) scanner. Two phantoms (one mouse-sized and one rat-sized) and two animal subjects (one mouse and one rat) were scanned in CTI Concorde Microsystem's microPET (registered) Focus{sup TM} for emission and transmission data and in ImTek's MicroCAT{sup TM} II for transmission data. PET emission image values were calibrated against a scintillation well counter. Results indicate that the scale factor method of attenuation correction places the average measured activity concentration about the expected value, without correcting for the cupping artefact from attenuation. Noise analysis in the phantom studies with the PET-based method shows that noise in the transmission data increases the noise in the corrected emission data. The CT-based method was accurate and delivered low-noise images suitable for both PET data correction and PET tracer localization.

  5. The Coriolis attenuation problem in 235U

    International Nuclear Information System (INIS)

    A new version of the particle-rotor model, featuring diagonalization of a state-dependent pairing force and the full recoil term, has been applied to 235U. A significant improvement is obtained in the description of the Coriolis coupled K=5/2, 7/2 and 9/2 rotational bands. No ad hoc Coriolis attenuation factors are used. (orig.)

  6. Electrically tunable hot-silicon terahertz attenuator

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Minjie [Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005 (United States); Vajtai, Robert; Ajayan, Pulickel M. [Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005 (United States); Kono, Junichiro, E-mail: kono@rice.edu [Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005 (United States); Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005 (United States); Department of Physics and Astronomy, Rice University, Houston, Texas 77005 (United States)

    2014-10-06

    We have developed a continuously tunable, broadband terahertz attenuator with a transmission tuning range greater than 10{sup 3}. Attenuation tuning is achieved electrically, by simply changing the DC voltage applied to a heating wire attached to a bulk silicon wafer, which controls its temperature between room temperature and ∼550 K, with the corresponding free-carrier density adjusted between ∼10{sup 11 }cm{sup −3} and ∼10{sup 17 }cm{sup −3}. This “hot-silicon”-based terahertz attenuator works most effectively at 450–550 K (corresponding to a DC voltage variation of only ∼7 V) and completely shields terahertz radiation above 550 K in a frequency range of 0.1–2.5 THz. Both intrinsic and doped silicon wafers were tested and demonstrated to work well as a continuously tunable attenuator. All behaviors can be understood quantitatively via the free-carrier Drude model taking into account thermally activated intrinsic carriers.

  7. Electrically tunable hot-silicon terahertz attenuator

    International Nuclear Information System (INIS)

    We have developed a continuously tunable, broadband terahertz attenuator with a transmission tuning range greater than 103. Attenuation tuning is achieved electrically, by simply changing the DC voltage applied to a heating wire attached to a bulk silicon wafer, which controls its temperature between room temperature and ∼550 K, with the corresponding free-carrier density adjusted between ∼1011 cm−3 and ∼1017 cm−3. This “hot-silicon”-based terahertz attenuator works most effectively at 450–550 K (corresponding to a DC voltage variation of only ∼7 V) and completely shields terahertz radiation above 550 K in a frequency range of 0.1–2.5 THz. Both intrinsic and doped silicon wafers were tested and demonstrated to work well as a continuously tunable attenuator. All behaviors can be understood quantitatively via the free-carrier Drude model taking into account thermally activated intrinsic carriers.

  8. GPR measurements of attenuation in concrete

    International Nuclear Information System (INIS)

    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

  9. ULTRASONIC ATTENUATION IN MIXED STATE OF NIOBIUM

    OpenAIRE

    Dominec, J.; MÍŠek, K.

    1987-01-01

    We have investigated the attenuation of ultrasonic waves in the mixed state of niobium, where a remarkable dip appears near the lower critical field . The measurement has been performed on one sample for various orientations of the wave vector and of the principal crystallographic axes of the sample with respect to external magnetic field.

  10. A recombinant canine distemper virus expressing a modified rabies virus glycoprotein induces immune responses in mice.

    Science.gov (United States)

    Li, Zhili; Wang, Jigui; Yuan, Daoli; Wang, Shuang; Sun, Jiazeng; Yi, Bao; Hou, Qiang; Mao, Yaping; Liu, Weiquan

    2015-06-01

    Canine distemper virus (CDV) and rabies virus (RV) are two important pathogens of the dog. CDV, a member of the morbillivirus genus, has shown promise as an expression vector. The glycoprotein from RV is a main contributor to protective immunity and capable of eliciting the production of virus-neutralizing antibodies. In this study, we recovered an attenuated strain of canine distemper virus and constructed a recombinant virus, rCDV-RV-G, expressing a modified (R333Q) rabies virus glycoprotein (RV-G) of RV Flury strain LEP. RV-G expression by the recombinant viruses was confirmed. Furthermore, G was proved to be incorporated into the surface of CDV particles. While replication of the recombinant virus was slightly reduced compared with the parental CDV, it stably expressed the RV-G over ten serial passages. Inoculation of mice induced specific neutralizing antibodies against both RV-G and CDV. Therefore, the rCDV-RV-G has the potential as a vaccine that may be used to control rabies virus infection in dogs and other animals. PMID:25764477

  11. 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.

  12. Jet fragmentation via recombination of parton showers

    Science.gov (United States)

    Han, Kyong Chol; Fries, Rainer J.; Ko, Che Ming

    2016-04-01

    We propose to model hadronization of parton showers in QCD jets through a hybrid approach involving quark recombination and string fragmentation. This is achieved by allowing gluons at the end of the perturbative shower evolution to undergo a nonperturbative splitting into quark and antiquark pairs, then applying a Monte Carlo version of instantaneous quark recombination, and finally subjecting remnant quarks (those which have not found a recombination partner) to Lund string fragmentation. When applied to parton showers from the pythia Monte Carlo event generator, the final hadron spectra from our calculation compare quite well to pythia jets that have been hadronized with the default Lund string fragmentation. Our new approach opens up the possibility to generalize hadronization to jets embedded in a quark gluon plasma.

  13. Comparison of recombination models in organic bulk heterojunction solar cells

    International Nuclear Information System (INIS)

    Recombination in bulk-heterojunction (BHJ) organic solar cells is the key loss mechanism, and it directly affects characteristic parameters such as power conversion efficiency, short-circuit current, open-circuit voltage, and fill factor. However, which recombination mechanism dominates the loss in organic materials is unclear at present. In this work, we simulate state-of-art BHJ solar cells using five recombination models, including direct recombination, Langevin recombination, charge transfer state recombination, trap-assisted recombination, and recombination via tail. All processes are strongly dependent on charge carrier mobility and exhibit a similar recombination distribution in active layer. For high mobilities, all models present a similar behavior along with the increased mobilities, whereas, there are slight differences in open-circuit voltage between trap/tail model and other ones at lower mobilities, resulting from the interaction between photo-carriers and dark-carriers

  14. Murine antibody response to oral infection with live aroA recombinant Salmonella dublin vaccine strains expressing filamentous hemagglutinin antigen from Bordetella pertussis.

    OpenAIRE

    Molina, N C; Parker, C D

    1990-01-01

    Two plasmids which express either nearly intact or truncated filamentous hemagglutinin (FHA) from Bordetella pertussis and which are marked with a tetracycline resistance (Tcr) gene were transformed into Salmonella dublin SL1438, an aroA deletion mutant intended for use as an attenuated oral vaccine against salmonellosis. These S. dublin recombinants, when fed to mice, induced serum immunoglobulin, immunoglobulin M (IgM), and sometimes IgA antibody responses to FHA and S. dublin. In addition,...

  15. SIR epidemics in monogamous populations with recombination

    CERN Document Server

    Zanette, Damián H

    2011-01-01

    We study the propagation of an SIR (susceptible-infectious-recovered) disease over an agent population which, at any instant, is fully divided into couples of agents. Couples are occasionally allowed to exchange their members. This process of couple recombination can compensate the instantaneous disconnection of the interaction pattern and thus allow for the propagation of the infection. We study the incidence of the disease as a function of its infectivity and of the recombination rate of couples, thus characterizing the interplay between the epidemic dynamics and the evolution of the population's interaction pattern.

  16. 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.

  17. Evaluation of satellite derived spectral diffuse attenuation coefficients

    Digital Repository Service at National Institute of Oceanography (India)

    Suresh, T.; Talaulikar, M.; Desa, E.; Mascarenhas, A.A.M.Q.; Matondkar, S.G.P.

    Spectral diffuse attenuation K sub(d)(lambda) is an important apparent optical property that provide information about the attenuation of the spectral downwelling solar irradiance with depth in water. The spectral K sub(d)(lambda) at lambda = 412...

  18. Interleukin-2/Anti-Interleukin-2 Immune Complex Attenuates Cardiac Remodeling after Myocardial Infarction through Expansion of Regulatory T Cells

    OpenAIRE

    Zhipeng Zeng; Kunwu Yu; Long Chen; Weihua Li; Hong Xiao; Zhengrong Huang

    2016-01-01

    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 significant...

  19. 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.

  20. Photon attenuation characteristics of radiation shielding materials

    International Nuclear Information System (INIS)

    In the design and construction of installation housing high intensity radiation sources and other radiation generating equipment, a variety of shielding materials are used to minimise exposure to individual. Among the materials, lead is best known for radiation shielding characteristics due to their high density and atomic number. Commercial and barium enriched cement, apart from better compressive strength, smoother surface finish and high abrasion resistance, offers adequate shielding to gamma radiations. Although photon attenuation data are available in literature, it is necessary to test these commercially available material experimentally for their radiation shielding efficiency before putting them in to regular use. In the present work, attenuation characteristics of lead. commercial cement and barium enriched cement supplied by a manufacturing firm have been studied for photons of 662 and 1250keV from Cs-137 and Co-60. The radiographic sources of Cs-137 and Co-60 of radioactive strength of 260 and 30 mCi respectively were utilised in the present investigation. Experimental measurements were done with gamma radiography survey meter MR 4500A placed at a distance of 2 meters from the source. Attenuation coefficients for photons in commercial cement, barite and lead were determined experimentally through photon transmission measurements performed under broad beam counting geometry. The absorbers used were in form of thin sheets of lead, commercial cements and barite of uniform thicknesses. These thin sheets were weighed accurately on an analytical balance and from their measured area, thicknesses proportional to area density in gram.cm-2 were determined. The average thickness of each absorber varied from a few milligram to several gram per cm-2. Higher thicknesses were obtained by stacking the absorbers with each other. Each absorber of specified thickness was interposed between the source and detector such that the primary beam is incident normally on its

  1. Breath-hold CT attenuation correction for quantitative cardiac SPECT

    OpenAIRE

    Koshino, Kazuhiro; Fukushima, Kazuhito; Fukumoto, Masaji; Sasaki, Kazunari; Moriguchi, Tetsuaki; Hori, Yuki; Zeniya, Tsutomu; Nishimura, Yoshihiro; Kiso, Keisuke; Iida, Hidehiro

    2012-01-01

    Background Attenuation correction of a single photon emission computed tomography (SPECT) image is possible using computed tomography (CT)-based attenuation maps with hybrid SPECT/CT. CT attenuation maps acquired during breath holding can be misaligned with SPECT, generating artifacts in the reconstructed images. The purpose of this study was to investigate the effects of respiratory phase during breath-hold CT acquisition on attenuation correction of cardiac SPECT imaging. Methods A series o...

  2. Recombinant microorganisms for increased production of organic acids

    Science.gov (United States)

    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.

  3. Simple Scheme for Variable High Power Laser Beam Attenuation

    OpenAIRE

    Bialkowski, Stephen E.

    1987-01-01

    A venetian style infrared attenuator placed prior to a pinhole spatial filter results in variable high‐power laser attenuation. This attenuation scheme has a wide dynamic range, results in high‐quality Gaussian beams, does not introduce beam walk‐off error, and is independent of polarization.

  4. 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.

  5. Attenuation of gamma radiation in concrete shields

    International Nuclear Information System (INIS)

    The attenuation characteristics of γ radiation in concrete layers considering their mechanical resistence and densities were determined. A 137Cs source was used in a 'good geometry' arrangement to eliminate the effects of the buildup factor. The ordinary and the heavy concrete were irradiated and for the latter it was used as additives iron ore and Fe2O3 pellets in various grain sizes. The detection system consisted of a 2' x 2' NaI (Tl) crystal coupled to a photomultiplier tube and the associated electronic equipment. FORTRAN programs were used for determining the absorption coefficients and the attenuation factors. These programs calculate photopeak areas eliminating all contributions due to Compton effect and background. (Author)

  6. Implicit temporal expectation attenuates auditory attentional blink.

    Directory of Open Access Journals (Sweden)

    Dawei Shen

    Full Text Available Attentional blink (AB describes a phenomenon whereby correct identification of a first target impairs the processing of a second target (i.e., probe nearby in time. Evidence suggests that explicit attention orienting in the time domain can attenuate the AB. Here, we used scalp-recorded, event-related potentials to examine whether auditory AB is also sensitive to implicit temporal attention orienting. Expectations were set up implicitly by varying the probability (i.e., 80% or 20% that the probe would occur at the +2 or +8 position following target presentation. Participants showed a significant AB, which was reduced with the increased probe probability at the +2 position. The probe probability effect was paralleled by an increase in P3b amplitude elicited by the probe. The results suggest that implicit temporal attention orienting can facilitate short-term consolidation of the probe and attenuate auditory AB.

  7. 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.

  8. Radiative recombination of excitons in amorphous semiconductors

    International Nuclear Information System (INIS)

    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

  9. Genetic Recombination as a Chemical Reaction Network

    OpenAIRE

    Müller, Stefan; Hofbauer, Josef

    2015-01-01

    The process of genetic recombination can be seen as a chemical reaction network with mass-action kinetics. We review the known results on existence, uniqueness, and global stability of an equilibrium in every compatibility class and for all rate constants, from both the population genetics and the reaction networks point of view.

  10. 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)

  11. 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.…

  12. Selected techniques in recombinant DNA technology

    International Nuclear Information System (INIS)

    Recombined DNA technology comprises a complex of techniques in the fields of nucleic acid biochemistry and molecular biology. This presentation gives an introduction, a brief description and example of the procedures of some of the basic techniques in the DNA cloning work currently used. 8 refs

  13. 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)

  14. Production and delivery of recombinant subunit vaccines

    OpenAIRE

    Andersson, Christin

    2000-01-01

    Recombinant strategies are today dominating in thedevelopment of modern subunit vaccines. This thesis describesstrategies for the production and recovery of protein subunitimmunogens, and how genetic design of the expression vectorscan be used to adapt the immunogens for incorporation intoadjuvant systems. In addition, different strategies fordelivery of subunit vaccines by RNA or DNA immunization havebeen investigated. Attempts to create general production strategies forrecombinant protein i...

  15. Asthma and Therapeutics: Recombinant Therapies in Asthma

    Directory of Open Access Journals (Sweden)

    Cockcroft Donald W

    2005-03-01

    Full Text Available Abstract Numerous recombinant therapies are being investigated for the treatment of asthma. This report reviews the current status of several of these novel agents. Anti-immunoglobulin (IgE (omalizumab, Xolair markedly inhibits all aspects of the allergen challenge in subjects who have reduction of free serum IgE to undetectable levels. Several clinical studies in atopic asthma have demonstrated benefit by improved symptoms and lung function and a reduction in corticosteroid requirements. Early use in atopic asthmatics may be even more effective. Several approaches target interleukin (IL-4. Soluble IL-4 receptor has been shown to effectively replace inhaled corticosteroid; further studies are under way. Recombinant anti-IL-5 and recombinant IL-12 inhibit blood and sputum eosinophils and allergen-induced eosinophilia without any effect on airway responsiveness, allergen-induced airway responses, or allergen-induced airway hyperresponsiveness. Efalizumab, a recombinant antibody that inhibits lymphocyte trafficking, is effective in psoriasis. A bronchoprovocation study showed a reduction in allergen-induced late asthmatic response and allergen-induced eosinophilia, which suggests that it should be effective in clinical asthma. These exciting novel therapies provide not only promise of new therapies for asthma but also valuable tools for investigation of asthma mechanisms.

  16. Catalytic hydrogen recombination for nuclear containments

    International Nuclear Information System (INIS)

    Catalytic recombiners appear to be a credible option for hydrogen mitigation in nuclear containments. The passive operation, versatility and ease of back fitting are appealing for existing stations and new designs. Recently, a generation of wet-proofed catalyst materials have been developed at AECL which are highly specific to H2-O2, are active at ambient temperatures and are being evaluated for containment applications. Two types of catalytic recombiners were evaluated for hydrogen removal in containments based on the AECL catalyst. The first is a catalytic combustor for application in existing air streams such as provided by fans or ventilation systems. The second is an autocatalytic recombiner which uses the enthalpy of reaction to produce natural convective flow over the catalyst elements. Intermediate-scale results obtained in 6 m3 and 10 m3 spherical and cylindrical vessels are given to demonstrate self-starting limits, operating limits, removal capacity, scaling parameters, flow resistance, mixing behaviour in the vicinity of an operating recombiner and sensitivity to poisoning, fouling and radiation. (author). 13 refs., 10 figs

  17. 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. PMID:26686863

  18. 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.

  19. Recombination times in germanium under high pressure

    International Nuclear Information System (INIS)

    The influence of pressure on a well defined recombination process was studied. The centres were introduced by γirradiation and the lifetime determined by the decay time of photoconductivity. An optical pressure vessel is described which allows for a hydrostatic variation of 3000 bars. The diffusion constant and lifetime measurements are presented and analysed. (V.J.C.)

  20. 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. PMID:23821459