1
|
E3 ubiquitin ligase Mindbomb 1 facilitates nuclear delivery of adenovirus genomes. Proc Natl Acad Sci U S A 2020; 118:2015794118. [PMID: 33443154 DOI: 10.1073/pnas.2015794118] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The journey from plasma membrane to nuclear pore is a critical step in the lifecycle of DNA viruses, many of which must successfully deposit their genomes into the nucleus for replication. Viral capsids navigate this vast distance through the coordinated hijacking of a number of cellular host factors, many of which remain unknown. We performed a gene-trap screen in haploid cells to identify host factors for adenovirus (AdV), a DNA virus that can cause severe respiratory illness in immune-compromised individuals. This work identified Mindbomb 1 (MIB1), an E3 ubiquitin ligase involved in neurodevelopment, as critical for AdV infectivity. In the absence of MIB1, we observed that viral capsids successfully traffic to the proximity of the nucleus but ultimately fail to deposit their genomes within. The capacity of MIB1 to promote AdV infection was dependent on its ubiquitination activity, suggesting that MIB1 may mediate proteasomal degradation of one or more negative regulators of AdV infection. Employing complementary proteomic approaches to characterize proteins proximal to MIB1 upon AdV infection and differentially ubiquitinated in the presence or absence of MIB1, we observed an intersection between MIB1 and ribonucleoproteins (RNPs) largely unexplored in mammalian cells. This work uncovers yet another way that viruses utilize host cell machinery for their own replication, highlighting a potential target for therapeutic interventions that counter AdV infection.
Collapse
|
2
|
Cunliffe TG, Bates EA, Parker AL. Hitting the Target but Missing the Point: Recent Progress towards Adenovirus-Based Precision Virotherapies. Cancers (Basel) 2020; 12:E3327. [PMID: 33187160 PMCID: PMC7696810 DOI: 10.3390/cancers12113327] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 10/31/2020] [Accepted: 11/09/2020] [Indexed: 12/23/2022] Open
Abstract
More people are surviving longer with cancer. Whilst this can be partially attributed to advances in early detection of cancers, there is little doubt that the improvement in survival statistics is also due to the expansion in the spectrum of treatments available for efficacious treatment. Transformative amongst those are immunotherapies, which have proven effective agents for treating immunogenic forms of cancer, although immunologically "cold" tumour types remain refractive. Oncolytic viruses, such as those based on adenovirus, have great potential as anti-cancer agents and have seen a resurgence of interest in recent years. Amongst their many advantages is their ability to induce immunogenic cell death (ICD) of infected tumour cells, thus providing the alluring potential to synergise with immunotherapies by turning immunologically "cold" tumours "hot". Additionally, enhanced immune mediated cell killing can be promoted through the local overexpression of immunological transgenes, encoded from within the engineered viral genome. To achieve this full potential requires the development of refined, tumour selective "precision virotherapies" that are extensively engineered to prevent off-target up take via native routes of infection and targeted to infect and replicate uniquely within malignantly transformed cells. Here, we review the latest advances towards this holy grail within the adenoviral field.
Collapse
Affiliation(s)
| | | | - Alan L. Parker
- Division of Cancer and Genetics, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK; (T.G.C.); (E.A.B.)
| |
Collapse
|
3
|
Douam F, Ziegler CGK, Hrebikova G, Fant B, Leach R, Parsons L, Wang W, Gaska JM, Winer BY, Heller B, Shalek AK, Ploss A. Selective expansion of myeloid and NK cells in humanized mice yields human-like vaccine responses. Nat Commun 2018; 9:5031. [PMID: 30487575 PMCID: PMC6262001 DOI: 10.1038/s41467-018-07478-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 10/29/2018] [Indexed: 12/21/2022] Open
Abstract
Mice engrafted with components of a human immune system have become widely-used models for studying aspects of human immunity and disease. However, a defined methodology to objectively measure and compare the quality of the human immune response in different models is lacking. Here, by taking advantage of the highly immunogenic live-attenuated yellow fever virus vaccine YFV-17D, we provide an in-depth comparison of immune responses in human vaccinees, conventional humanized mice, and second generation humanized mice. We demonstrate that selective expansion of human myeloid and natural killer cells promotes transcriptomic responses akin to those of human vaccinees. These enhanced transcriptomic profiles correlate with the development of an antigen-specific cellular and humoral response to YFV-17D. Altogether, our approach provides a robust scoring of the quality of the human immune response in humanized mice and highlights a rational path towards developing better pre-clinical models for studying the human immune response and disease.
Collapse
Affiliation(s)
- Florian Douam
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Washington Road, Princeton, NJ, 08544, USA
| | - Carly G K Ziegler
- Institute for Medical Engineering & Science (IMES), MIT, Cambridge, MA, 02139, USA
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, 02142, USA
- Harvard-MIT Division of Health Sciences and Technology, Harvard Medical School, Boston, MA, 02139, USA
- Graduate Program in Biophysics, Harvard Medical School, Boston, MA, 02139, USA
| | - Gabriela Hrebikova
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Washington Road, Princeton, NJ, 08544, USA
| | - Bruno Fant
- Department of Psychiatry, Center for Neurobiology and Behavior, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Robert Leach
- Lewis Sigler Institute for Integrative Genomics, Genomics Core, Carl Icahn Laboratory, Princeton University, Princeton, NJ, 19104, USA
| | - Lance Parsons
- Lewis Sigler Institute for Integrative Genomics, Genomics Core, Carl Icahn Laboratory, Princeton University, Princeton, NJ, 19104, USA
| | - Wei Wang
- Lewis Sigler Institute for Integrative Genomics, Genomics Core, Carl Icahn Laboratory, Princeton University, Princeton, NJ, 19104, USA
| | - Jenna M Gaska
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Washington Road, Princeton, NJ, 08544, USA
| | - Benjamin Y Winer
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Washington Road, Princeton, NJ, 08544, USA
| | - Brigitte Heller
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Washington Road, Princeton, NJ, 08544, USA
| | - Alex K Shalek
- Institute for Medical Engineering & Science (IMES), MIT, Cambridge, MA, 02139, USA
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, 02142, USA
- Harvard-MIT Division of Health Sciences and Technology, Harvard Medical School, Boston, MA, 02139, USA
- Graduate Program in Biophysics, Harvard Medical School, Boston, MA, 02139, USA
| | - Alexander Ploss
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Washington Road, Princeton, NJ, 08544, USA.
| |
Collapse
|
4
|
Mice Expressing Minimally Humanized CD81 and Occludin Genes Support Hepatitis C Virus Uptake In Vivo. J Virol 2017; 91:JVI.01799-16. [PMID: 27928007 DOI: 10.1128/jvi.01799-16] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 11/23/2016] [Indexed: 02/07/2023] Open
Abstract
Hepatitis C virus (HCV) causes chronic infections in at least 150 million individuals worldwide. HCV has a narrow host range and robustly infects only humans and chimpanzees. The underlying mechanisms for this narrow host range are incompletely understood. At the level of entry, differences in the amino acid sequences between the human and mouse orthologues of two essential host factors, the tetraspanin CD81 and the tight junction protein occludin (OCLN), explain, at least in part, HCV's limited ability to enter mouse hepatocytes. We have previously shown that adenoviral or transgenic overexpression of human CD81 and OCLN facilitates HCV uptake into mouse hepatocytes in vitro and in vivo In efforts to refine these models, we constructed knock-in mice in which the second extracellular loops of CD81 and OCLN were replaced with the respective human sequences, which contain the determinants that are critical for HCV uptake. We demonstrate that the humanized CD81 and OCLN were expressed at physiological levels in a tissue-appropriate fashion. Mice bearing the humanized alleles formed normal tight junctions and did not exhibit any immunologic abnormalities, indicating that interactions with their physiological ligands were intact. HCV entry factor knock-in mice take up HCV with an efficiency similar to that in mice expressing HCV entry factors transgenically or adenovirally, demonstrating the utility of this model for studying HCV infection in vivo IMPORTANCE: At least 150 million individuals are chronically infected with hepatitis C virus (HCV). Chronic hepatitis C can result in progressive liver disease and liver cancer. New antiviral treatments can cure HCV in the majority of patients, but a vaccine remains elusive. To gain a better understanding of the processes culminating in liver failure and cancer and to prioritize vaccine candidates more efficiently, small-animal models are needed. Here, we describe the characterization of a new mouse model in which the parts of two host factors that are essential for HCV uptake, CD81 and occludin (OCLN), which differ between mice and humans, were humanized. We demonstrate that such minimally humanized mice develop normally, express the modified genes at physiological levels, and support HCV uptake. This model is of considerable utility for studying viral entry in the three-dimensional context of the liver and to test approaches aimed at preventing HCV entry.
Collapse
|
5
|
de Jong YP, Dorner M, Mommersteeg MC, Xiao JW, Balazs AB, Robbins JB, Winer BY, Gerges S, Vega K, Labitt RN, Donovan BM, Giang E, Krishnan A, Chiriboga L, Charlton MR, Burton DR, Baltimore D, Law M, Rice CM, Ploss A. Broadly neutralizing antibodies abrogate established hepatitis C virus infection. Sci Transl Med 2015; 6:254ra129. [PMID: 25232181 DOI: 10.1126/scitranslmed.3009512] [Citation(s) in RCA: 177] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In most exposed individuals, hepatitis C virus (HCV) establishes a chronic infection; this long-term infection in turn contributes to the development of liver diseases such as cirrhosis and hepatocellular carcinoma. The role of antibodies directed against HCV in disease progression is poorly understood. Neutralizing antibodies (nAbs) can prevent HCV infection in vitro and in animal models. However, the effects of nAbs on an established HCV infection are unclear. We demonstrate that three broadly nAbs-AR3A, AR3B, and AR4A-delivered with adeno-associated viral vectors can confer protection against viral challenge in humanized mice. Furthermore, we provide evidence that nAbs can abrogate an ongoing HCV infection in primary hepatocyte cultures and in a human liver chimeric mouse model. These results showcase a therapeutic approach to interfere with HCV infection by exploiting a previously unappreciated need for HCV to continuously infect new hepatocytes to sustain a chronic infection.
Collapse
Affiliation(s)
- Ype P de Jong
- Center for the Study of Hepatitis C, Division of Gastroenterology and Hepatology, Weill Cornell Medical College, New York, NY 10065, USA. Center for the Study of Hepatitis C, Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA.
| | - Marcus Dorner
- Center for the Study of Hepatitis C, Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - Michiel C Mommersteeg
- Center for the Study of Hepatitis C, Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - Jing W Xiao
- Center for the Study of Hepatitis C, Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | | | - Justin B Robbins
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Benjamin Y Winer
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Sherif Gerges
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Kevin Vega
- Center for the Study of Hepatitis C, Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - Rachael N Labitt
- Center for the Study of Hepatitis C, Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - Bridget M Donovan
- Center for the Study of Hepatitis C, Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - Erick Giang
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Anuradha Krishnan
- Division of Gastroenterology and Hepatology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Luis Chiriboga
- Department of Pathology, New York University Medical Center, New York, NY 10016, USA
| | - Michael R Charlton
- Division of Gastroenterology and Hepatology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Dennis R Burton
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA. Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - David Baltimore
- Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA
| | - Mansun Law
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Charles M Rice
- Center for the Study of Hepatitis C, Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - Alexander Ploss
- Center for the Study of Hepatitis C, Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA. Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.
| |
Collapse
|
6
|
Behr M, Kaufmann JK, Ketzer P, Engelhardt S, Mück-Häusl M, Okun PM, Petersen G, Neipel F, Hassel JC, Ehrhardt A, Enk AH, Nettelbeck DM. Adenoviruses using the cancer marker EphA2 as a receptor in vitro and in vivo by genetic ligand insertion into different capsid scaffolds. PLoS One 2014; 9:e95723. [PMID: 24760010 PMCID: PMC3997477 DOI: 10.1371/journal.pone.0095723] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 03/30/2014] [Indexed: 11/18/2022] Open
Abstract
Adenoviral gene therapy and oncolysis would critically benefit from targeted cell entry by genetically modified capsids. This requires both the ablation of native adenovirus tropism and the identification of ligands that remain functional in virus context. Here, we establish cell type-specific entry of HAdV-5-based vectors by genetic ligand insertion into a chimeric fiber with shaft and knob domains of the short HAdV-41 fiber (Ad5T/41sSK). This fiber format was reported to ablate transduction in vitro and biodistribution to the liver in vivo. We show that the YSA peptide, binding to the pan-cancer marker EphA2, can be inserted into three positions of the chimeric fiber, resulting in strong transduction of EphA2-positive but not EphA2-negative cells of human melanoma biopsies and of tumor xenografts after intratumoral injection. Transduction was blocked by soluble YSA peptide and restored for EphA2-negative cells after recombinant EphA2 expression. The YSA peptide could also be inserted into three positions of a CAR binding-ablated HAdV-5 fiber enabling specific transduction; however, the Ad5T/41sSK format was superior in vivo. In conclusion, we establish an adenovirus capsid facilitating functional insertion of targeting peptides and a novel adenovirus using the tumor marker EphA2 as receptor with high potential for cancer gene therapy and viral oncolysis.
Collapse
Affiliation(s)
- Michael Behr
- Oncolytic Adenovirus Group, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Johanna K. Kaufmann
- Oncolytic Adenovirus Group, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Patrick Ketzer
- Oncolytic Adenovirus Group, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Sarah Engelhardt
- Oncolytic Adenovirus Group, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Martin Mück-Häusl
- Max von Pettenkofer-Institute, Department of Virology, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Pamela M. Okun
- Department of General Pediatrics, Division of Inherited Metabolic Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Gabriele Petersen
- COS, CellNetworks Deep Sequencing Core Facility, University Heidelberg, Heidelberg, Germany
| | - Frank Neipel
- Institute for Clinical and Molecular Virology, Erlangen University Hospital, Erlangen, Germany
| | - Jessica C. Hassel
- Department of Dermatology, Heidelberg University Hospital, Heidelberg, Germany
| | - Anja Ehrhardt
- Max von Pettenkofer-Institute, Department of Virology, Ludwig-Maximilians-University Munich, Munich, Germany
- Institute of Virology and Microbiology, Center for Biomedical Education and Research, Department of Human Medicine, Faculty of Health, University Witten/Herdecke, Witten, Germany
| | - Alexander H. Enk
- Department of Dermatology, Heidelberg University Hospital, Heidelberg, Germany
| | - Dirk M. Nettelbeck
- Oncolytic Adenovirus Group, German Cancer Research Center (DKFZ), Heidelberg, Germany
- * E-mail:
| |
Collapse
|
7
|
Song JD, Liu XL, Chen DL, Zou XH, Wang M, Qu JG, Lu ZZ, Hung T. Human adenovirus type 41 possesses different amount of short and long fibers in the virion. Virology 2012; 432:336-42. [DOI: 10.1016/j.virol.2012.05.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Revised: 04/24/2012] [Accepted: 05/24/2012] [Indexed: 10/28/2022]
|
8
|
Miralles M, Segura MM, Puig M, Bosch A, Chillon M. Efficient amplification of chimeric adenovirus 5/40S vectors carrying the short fiber protein of Ad40 in suspension cell cultures. PLoS One 2012; 7:e42073. [PMID: 22860056 PMCID: PMC3409147 DOI: 10.1371/journal.pone.0042073] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Accepted: 07/02/2012] [Indexed: 01/20/2023] Open
Abstract
The human adenovirus 40 (Ad40) is a promising tool for gene therapy of intestinal diseases. Since the production of Ad40 in vitro is extremely inefficient, chimeric Adenovirus 5/40S vectors carrying the Ad40 short fiber on the Ad5 capsid have been developed. However, Ad5/40S productivity is low. We hypothesized that low productivity was a result of inefficient viral entry into producer cells during amplification. To this end, we have developed a production strategy based on using 211B cells (expressing Ad5 fiber) during amplification steps, while Ad5/40S infectivity is further improved by adding polybrene during infections. In addition, the optimal harvesting time was determined by evaluating the Ad5/40S viral cycle. The developed production strategy significantly reduces the number of amplification cycles and duration of the process. Finally, to further facilitate Ad5/40S production, 211B cells were adapted to suspension thus allowing to easily upscale the production process in bioreactors.
Collapse
Affiliation(s)
- Marta Miralles
- Center of Animal Biotechnology and Gene Therapy (CBATEG), and Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - María Mercedes Segura
- Center of Animal Biotechnology and Gene Therapy (CBATEG), and Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Meritxell Puig
- Center of Animal Biotechnology and Gene Therapy (CBATEG), and Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Assumpció Bosch
- Center of Animal Biotechnology and Gene Therapy (CBATEG), and Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Miguel Chillon
- Center of Animal Biotechnology and Gene Therapy (CBATEG), and Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, Barcelona, Spain
- Institut Català de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
- * E-mail:
| |
Collapse
|
9
|
Kaufmann JK, Nettelbeck DM. Virus chimeras for gene therapy, vaccination, and oncolysis: adenoviruses and beyond. Trends Mol Med 2012; 18:365-76. [PMID: 22633438 DOI: 10.1016/j.molmed.2012.04.008] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Revised: 04/19/2012] [Accepted: 04/20/2012] [Indexed: 12/27/2022]
Abstract
Several challenges need to be addressed when developing viruses for clinical applications in gene therapy, vaccination, or viral oncolysis, including specific and efficient target cell transduction, virus delivery via the blood stream, and evasion of pre-existing immunity. With rising frequency, these goals are tackled by generating chimeric viruses containing nucleic acid fragments or proteins from two or more different viruses, thus combining different beneficial features of the parental viruses. These chimeras have boosted the development of virus-based treatment regimens for major inherited and acquired diseases, including cancer. Using adenoviruses as the paradigm and prominent examples from other virus families, we review the technological and functional advances in therapeutic virus chimera development and recent successful applications that can pave the way for future therapies.
Collapse
Affiliation(s)
- Johanna K Kaufmann
- Helmholtz University Group Oncolytic Adenoviruses, German Cancer Research Center (DKFZ) and Department of Dermatology, Heidelberg University Hospital, Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
| | | |
Collapse
|
10
|
Zou XH, Xiao X, Chen DL, Li ZL, Song JD, Wang M, Qu JG, Lu ZZ, Hung T. An improved HAdV-41 E1B55K-expressing 293 cell line for packaging fastidious adenovirus. J Virol Methods 2011; 175:188-96. [DOI: 10.1016/j.jviromet.2011.05.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Revised: 04/06/2011] [Accepted: 05/05/2011] [Indexed: 10/18/2022]
|
11
|
Dorner M, Horwitz JA, Robbins JB, Barry WT, Feng Q, Mu K, Jones CT, Schoggins JW, Catanese MT, Burton DR, Law M, Rice CM, Ploss A. A genetically humanized mouse model for hepatitis C virus infection. Nature 2011; 474:208-11. [PMID: 21654804 PMCID: PMC3159410 DOI: 10.1038/nature10168] [Citation(s) in RCA: 285] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2011] [Accepted: 04/28/2011] [Indexed: 02/06/2023]
Abstract
Hepatitis C virus (HCV) remains a major medical problem. Antiviral treatment is only partially effective and a vaccine does not exist. Development of more effective therapies has been hampered by the lack of a suitable small animal model. Although xenotransplantation of immunodeficient mice with human hepatocytes has shown promise, these models are subject to important challenges. Building on the previous observation that CD81 and occludin comprise the minimal human factors required to render mouse cells permissive to HCV entry in vitro, we attempted murine humanization via a genetic approach. Here we show that expression of two human genes is sufficient to allow HCV infection of fully immunocompetent inbred mice. We establish a precedent for applying mouse genetics to dissect viral entry and validate the role of scavenger receptor type B class I for HCV uptake. We demonstrate that HCV can be blocked by passive immunization, as well as showing that a recombinant vaccinia virus vector induces humoral immunity and confers partial protection against heterologous challenge. This system recapitulates a portion of the HCV life cycle in an immunocompetent rodent for the first time, opening opportunities for studying viral pathogenesis and immunity and comprising an effective platform for testing HCV entry inhibitors in vivo.
Collapse
Affiliation(s)
- Marcus Dorner
- Center for the Study of Hepatitis C, The Rockefeller University, New York, New York 10065, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Corjon S, Gonzalez G, Henning P, Grichine A, Lindholm L, Boulanger P, Fender P, Hong SS. Cell entry and trafficking of human adenovirus bound to blood factor X is determined by the fiber serotype and not hexon:heparan sulfate interaction. PLoS One 2011; 6:e18205. [PMID: 21637339 PMCID: PMC3102659 DOI: 10.1371/journal.pone.0018205] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Accepted: 02/28/2011] [Indexed: 01/29/2023] Open
Abstract
Human adenovirus serotype 5 (HAdV5)-based vectors administered intravenously accumulate in the liver as the result of their direct binding to blood coagulation factor X (FX) and subsequent interaction of the FX-HAdV5 complex with heparan sulfate proteoglycan (HSPG) at the surface of liver cells. Intriguingly, the serotype 35 fiber-pseudotyped vector HAdV5F35 has liver transduction efficiencies 4-logs lower than HAdV5, even though both vectors carry the same hexon capsomeres. In order to reconcile this apparent paradox, we investigated the possible role of other viral capsid proteins on the FX/HSPG-mediated cellular uptake of HAdV5-based vectors. Using CAR- and CD46-negative CHO cells varying in HSPG expression, we confirmed that FX bound to serotype 5 hexon protein and to HAdV5 and HAdV5F35 virions via its Gla-domain, and enhanced the binding of both vectors to surface-immobilized hypersulfated heparin and cellular HSPG. Using penton mutants, we found that the positive effect of FX on HAdV5 binding to HSPG and cell transduction did not depend on the penton base RGD and fiber shaft KKTK motifs. However, we found that FX had no enhancing effect on the HAdV5F35-mediated cell transduction, but a negative effect which did not involve the cell attachment or endocytic step, but the intracellular trafficking and nuclear import of the FX-HAdV5F35 complex. By cellular imaging, HAdV5F35 particles were observed to accumulate in the late endosomal compartment, and were released in significant amounts into the extracellular medium via exocytosis. We showed that the stability of serotype 5 hexon:FX interaction was higher at low pH compared to neutral pH, which could account for the retention of FX-HAdV5F35 complexes in the late endosomes. Our results suggested that, despite the high affinity interaction of hexon capsomeres to FX and cell surface HSPG, the adenoviral fiber acted as the dominant determinant of the internalization and trafficking pathway of HAdV5-based vectors.
Collapse
Affiliation(s)
- Stéphanie Corjon
- University Lyon 1, INRA UMR 754, Retrovirus
and Comparative Pathology, Lyon, France
| | - Gaëlle Gonzalez
- University Lyon 1, INRA UMR 754, Retrovirus
and Comparative Pathology, Lyon, France
| | - Petra Henning
- Department of Microbiology and Immunology,
University of Göteborg, Institute for Biomedicine, Göteborg,
Sweden
| | - Alexei Grichine
- Institut Albert Bonniot, CRI INSERM-UJF U-823,
La Tronche, France
| | | | - Pierre Boulanger
- University Lyon 1, INRA UMR 754, Retrovirus
and Comparative Pathology, Lyon, France
| | - Pascal Fender
- Unit for Virus-Host Interaction, UMI-3265,
CNRS-EMBL-UJF, Grenoble, France
| | - Saw-See Hong
- University Lyon 1, INRA UMR 754, Retrovirus
and Comparative Pathology, Lyon, France
| |
Collapse
|
13
|
Unity and diversity in the human adenoviruses: exploiting alternative entry pathways for gene therapy. Biochem J 2010; 431:321-36. [DOI: 10.1042/bj20100766] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Human Ads (adenoviruses) have been extensively utilized for the development of vectors for gene transfer, as they infect many cell types and do not integrate their genome into host-cell chromosomes. In addition, they have been widely studied as cytolytic viruses, termed oncolytic adenoviruses in cancer therapy. Ads are non-enveloped viruses with a linear double-stranded DNA genome of 30–38 kb which encodes 30–40 genes. At least 52 human Ad serotypes have been identified and classified into seven species, A–G. The Ad capsid has icosahedral symmetry and is composed of 252 capsomers, of which 240 are located on the facets of the capsid and consist of a trimeric hexon protein and the remaining 12 capsomers, the pentons, are at the vertices and comprise the penton base and projecting fibre protein. The entry of Ads into human cells is a two-step process. In the first step, the fibre protein mediates a primary interaction with the cell, effectively tethering the virus particle to the cell surface via a cellular attachment protein. The penton base then interacts with cell-surface integrins, leading to virus internalization. This interaction of the fibre protein with a number of cell-surface molecules appears to be important in determining the tropism of adenoviruses. Ads from all species, except species B and certain serotypes of species D, utilize CAR (coxsackie and adenovirus receptor) as their primary cellular-attachment protein, whereas most species B Ads use CD46, a complement regulatory protein. Such species-specific differences, as well as adaptations or modifications of Ads required for applications in gene therapy, form the major focus of the present review.
Collapse
|
14
|
Murakami M, Ugai H, Wang M, Belousova N, Dent P, Fisher PB, Glasgow JN, Everts M, Curiel DT. An adenoviral vector expressing human adenovirus 5 and 3 fiber proteins for targeting heterogeneous cell populations. Virology 2010; 407:196-205. [PMID: 20828776 DOI: 10.1016/j.virol.2010.08.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2010] [Revised: 06/09/2010] [Accepted: 08/12/2010] [Indexed: 11/16/2022]
Abstract
Human adenovirus serotype 5 (HAdV-5) attaches to its primary receptor, the coxsackie and adenovirus receptor (CAR) as the first step of infection. However, CAR expression decreases as tumors progress, thereby diminishing the utility of HAdV-5-based vectors for cancer therapy. In contrast, many aggressive tumor cells highly express CD46, a cellular receptor for HAdV-3. We hypothesized that a mosaic HAdV vector, containing two kinds of fiber proteins, would provide extensive transduction in a heterogeneous population of tumor cells with varying expression levels of HAdV receptors. We therefore generated a fiber-mosaic HAdV vector displaying both a chimeric HAdV-3 fiber and the HAdV-5 fiber protein. We verified the structural integrity of purified viral particles and confirmed that the fiber-mosaic HAdV vector has expanded tropism. We conclude that the use of fiber-mosaic HAdV vectors is a promising approach for transducing a heterogeneous cell population with different expression levels of adenovirus receptors.
Collapse
Affiliation(s)
- Miho Murakami
- Division of Human Gene Therapy, Department of Medicine, The University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Schoggins JW, Falck-Pedersen E. Serotype 5 Adenovirus fiber (F7F41S) chimeric vectors incur packaging deficiencies when targeting peptides are inserted into Ad41 short fiber. Virology 2009; 395:10-20. [PMID: 19782383 DOI: 10.1016/j.virol.2009.08.041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Revised: 06/17/2009] [Accepted: 08/28/2009] [Indexed: 01/25/2023]
Abstract
Adenovirus is a well-established viral gene transfer model system that presents two major hurdles when being considered for cell-specific targeting applications. First is the need to detarget the vector from inherent host binding mechanisms, and second is the need to establish a productive and stable method to retarget the vector to a desired cell receptor. In previous studies we had generated an adenovirus vector platform that lacks the normal targeting attributes derived from the fiber and penton capsid proteins. In the current study we characterized our detargeted Ad5-based vectors (Ad5.F7F41S and Ad5.F7F41SDeltaRGD) as platforms for novel retargeted viruses. The experimental strategy relied on incorporating small peptide ligands into several sites of the Ad 41short fiber knob domain (AB, CD, HI, G and Cterm). Reengineering of Ad41 short fiber resulted either in a bypass to fiber 7 usage, or in a dominant negative packaging/production deficiency phenotype. Under specific growth conditions we could remedy some of the capsid deficiencies and generate high titer viruses. However when examined by Western blot analysis, the resulting viruses were still defective in capsid content. The tandem fiber F7F41S platform has revealed an unanticipated sensitivity of Adenovirus packaging to fiber 41short structural modifications. These studies indicate fiber assembly into an intact virion or fiber influenced capsid stability as a bottleneck to efficient particle production. We also demonstrate that virus particles characterized as mature virions following CsCl banding can vary significantly in capsid protein content. Considering the complexity of virus entry into a target cell, modified "mature virions" may be compromised at the level of transduction not only through the intended modification, but also by virtue of secondary structural packaging conflicts.
Collapse
Affiliation(s)
- John W Schoggins
- Weill Medical College of Cornell University, Hearst Research Foundation, Department of Microbiology and Immunology, Molecular Biology Graduate Program, 1300 York Avenue, New York, NY 10021, USA
| | | |
Collapse
|
16
|
Short JJ, Curiel DT. Oncolytic adenoviruses targeted to cancer stem cells: Table 1. Mol Cancer Ther 2009; 8:2096-102. [DOI: 10.1158/1535-7163.mct-09-0367] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
17
|
Arnberg N. Adenovirus receptors: implications for tropism, treatment and targeting. Rev Med Virol 2009; 19:165-78. [PMID: 19367611 DOI: 10.1002/rmv.612] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Adenoviruses (Ads) are the most frequently used viral vectors in gene therapy and cancer therapy. Obstacles to successful clinical application include accumulation of vector and transduction in liver cells, coupled with poor transduction of target cells and tissues such as tumours. Many host molecules, including coagulation factor X, have been identified and suggested to serve as mediators of Ad liver tropism. This review summarises current knowledge concerning these molecules and the mechanisms used by Ads to bind to target cells, and considers the prospects of designing vectors that have been detargeted from the liver and retargeted to cells and tissues of interest in the context of gene therapy and cancer therapy.
Collapse
Affiliation(s)
- Niklas Arnberg
- Division of Virology, Department of Clinical Microbiology, Umeå University, Umeå, SE-901 85, Sweden.
| |
Collapse
|
18
|
Lu ZZ, Zou XH, Dong LX, Qu JG, Song JD, Wang M, Guo L, Hung T. Novel recombinant adenovirus type 41 vector and its biological properties. J Gene Med 2009; 11:128-38. [PMID: 19097028 DOI: 10.1002/jgm.1284] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Human adenovirus serotype 41 (Ad41) is a natural pathogen of the digestive tract and can cause gastroenteritis. There has been interest in reconstructing Ad41 as a gene delivery vector targeting the gastrointestinal tract, which is hampered by its fastidiousness. METHODS An Ad41 E1B55K-transduced 293 cell line (293E12) was established as the packaging cell line. A backbone plasmid (pAdbone41) and a shuttle plasmid (pSh41-CMV) were constructed based on the Ad41 genome. Replication-defective adenovirus (Ad41-GFP) was rescued in 293E12 after being transfected with the linearized adenoviral plasmid, which was generated by homologous recombination of pAdbone41 and the shuttle plasmid carrying the GFP gene in Escherichia coli strain BJ5183. The packaging ability of 293E12, the stability of the Ad41-GFP genome and the acid-resistant property of Ad41-GFP were all investigated. RESULTS A 293E12 cell could produce approximately 9000 viral particles of Ad41-GFP, which is close to the amount in the control virus (Ad5-GFP) amplified in one 293 cell. Ad41-GFP contained a genetically stable genome after being passaged eight times in 293E12 cells. More significantly, Ad41-GFP was more resistant to acid exposure than Ad5-GFP. It retained almost complete viability when exposed to hydrochloric acid with a pH value of 2 for 30 min, whereas Ad5-GFP lost 99% of its viability under the same conditions. Ad41-GFP was also more tolerant to treatment with artificial digestive fluid. CONCLUSIONS An Ad41 vector system was successfully constructed, which consisted of the backbone plasmid, shuttle plasmid and packaging cell line 293E12. This system can be utilized to generate genetically stable and acid-resistant recombinant Ad41 carrying any gene of interest.
Collapse
Affiliation(s)
- Zhuo-Zhuang Lu
- National Institute for Viral Disease Control and Prevention, Chinese Centre for Disease Control and Prevention, Beijing, PR China
| | | | | | | | | | | | | | | |
Collapse
|
19
|
Kashentseva EA, Douglas JT, Zinn KR, Curiel DT, Dmitriev IP. Targeting of adenovirus serotype 5 pseudotyped with short fiber from serotype 41 to c-erbB2-positive cells using bispecific single-chain diabody. J Mol Biol 2009; 388:443-61. [PMID: 19285990 DOI: 10.1016/j.jmb.2009.03.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2008] [Revised: 02/20/2009] [Accepted: 03/09/2009] [Indexed: 11/18/2022]
Abstract
The purpose of the current study was to alter the broad native tropism of human adenovirus for virus targeting to c-erbB2-positive cancer cells. First, we engineered a single-chain antibody (scFv) against the c-erbB2 oncoprotein into minor capsid protein IX (pIX) of adenovirus serotype 5 (Ad5) in a manner commensurate with virion integrity and binding to the soluble extracellular c-erbB2 domain. To ablate native viral tropism and facilitate binding of the pIX-incorporated scFv to cellular c-erbB2, we replaced the Ad5 fiber with the Ad41 short (41s) fiber devoid of all known cell-binding determinants. The resultant Ad5F41sIX6.5 vector demonstrated increased cell binding and gene transfer as compared to the Ad5F41s control; however, this augmentation of virus infectivity was not c-erbB2 specific. Incorporation of a six-histidine (His(6)) peptide into the C-terminus of the 41s fiber protein resulted in markedly increased Ad5F41s6H infectivity in 293AR cells, which express a membrane-anchored scFv against the C-terminal oligohistidine tag, as compared to the Ad5F41s vector and the parental 293 cells. These data suggested that a 41s-fiber-incorporated His(6) tag could serve for attachment of an adapter protein designed to guide Ad5F41s6H infection in a c-erbB2-specific manner. We therefore engineered a bispecific scFv diabody (scDb) combining affinities for both c-erbB2 and the His(6) tag and showed its ability to provide up to 25-fold increase of Ad5F41s6H infectivity in c-erbB2-positive cells. Thus, Ad5 fiber replacement by a His(6)-tagged 41s fiber coupled with virus targeting mediated by an scDb adapter represents a promising strategy to confer Ad5 vector tropism for c-erbB2-positive cancer cells.
Collapse
Affiliation(s)
- Elena A Kashentseva
- Division of Human Gene Therapy, Departments of Medicine, Obstetrics and Gynecology, Pathology, and Surgery, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | | | | | | | | |
Collapse
|
20
|
Abstract
The best hope of controlling the HIV pandemic is the development of an effective vaccine. In addition to the stimulation of virus neutralising antibodies, a vaccine will need an effective T-cell response against the virus. Vaccines based on recombinant adenoviruses (rAd) are promising candidates to stimulate anti-HIV T-cell responses. This review discusses the different rAd vector types, problems raised by host immune responses against them and strategies that are being adopted to overcome this problem. Vaccines need to target and stimulate dendritic cells and thus the tropism and interaction of rAd-based vaccines with these cells is covered. Different rAd vaccination regimes and the need to stimulate mucosal responses are discussed together with data from animal studies on immunogenicity and virus challenge experiments. The review ends with a discussion of the recent disappointing Merck HIV vaccine trial.
Collapse
Affiliation(s)
- Steven Patterson
- Department of Immunology, Imperial College, Chelsea and Westminster Hospital, London, UK.
| | | | | |
Collapse
|
21
|
Enhanced induction of intestinal cellular immunity by oral priming with enteric adenovirus 41 vectors. J Virol 2008; 83:748-56. [PMID: 18987146 DOI: 10.1128/jvi.01811-08] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) infection is characterized by the rapid onset of intestinal T-cell depletion that initiates the progression to AIDS. The induction of protective immunity in the intestinal mucosa therefore represents a potentially desirable feature of a preventive AIDS vaccine. In this study, we have evaluated the ability of an enteric adenovirus, recombinant adenovirus 41 (rAd41), to elicit intestinal and systemic immune responses by different immunization routes, alone or in combination with rAd5. rAd41 expressing HIV envelope (Env) protein induced cellular immune responses comparable to those of rAd5-based vectors after either a single intramuscular injection or a DNA prime/rAd boost. Oral priming with rAd41-Env followed by intramuscular boosting with rAd5-Env stimulated a more potent CD8(+) T-cell response in the small intestine than the other immunization regimens. Furthermore, the direct injection of rAd41-Env into ileum together with intramuscular rAd5-Env boosting increased Env-specific cellular immunity markedly in mucosal as well as systemic compartments. These data demonstrate that heterologous rAd41 oral or ileal priming with rAd5 intramuscular boosting elicits enhanced intestinal mucosal cellular immunity and that oral or ileal vector delivery for primary immunization facilitates the generation of mucosal immunity.
Collapse
|
22
|
Adenovirus serotype 5 hexon is critical for virus infection of hepatocytes in vivo. Proc Natl Acad Sci U S A 2008; 105:5483-8. [PMID: 18391209 DOI: 10.1073/pnas.0711757105] [Citation(s) in RCA: 268] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Human species C adenovirus serotype 5 (Ad5) is the most common viral vector used in clinical studies worldwide. Ad5 vectors infect liver cells in vivo with high efficiency via a poorly defined mechanism, which involves virus binding to vitamin K-dependent blood coagulation factors. Here, we report that the major Ad5 capsid protein, hexon, binds human coagulation factor X (FX) with an affinity of 229 pM. This affinity is 40-fold stronger than the reported affinity of Ad5 fiber for the cellular receptor coxsackievirus and adenovirus receptor, CAR. Cryoelectron microscopy and single-particle image reconstruction revealed that the FX attachment site is localized to the central depression at the top of the hexon trimer. Hexon-mutated virus bearing a large insertion in hexon showed markedly reduced FX binding in vitro and failed to deliver a transgene to hepatocytes in vivo. This study describes the mechanism of FX binding to Ad5 and demonstrates the critical role of hexon for virus infection of hepatocytes in vivo.
Collapse
|
23
|
Protective immunity to pseudomonas aeruginosa induced with a capsid-modified adenovirus expressing P. aeruginosa OprF. J Virol 2007; 81:13801-8. [PMID: 17942539 DOI: 10.1128/jvi.01246-07] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This study focuses on the development of a new clinical vaccine candidate (AdOprF.RGD.Epi8) against Pseudomonas aeruginosa using an E1(-) E3(-) adenovirus (Ad) vector expressing OprF (AdOprF.RGD.Epi8) and modifications of the Ad genome providing two capsid changes: (i) modification of the Ad hexon gene to incorporate an immune-dominant OprF epitope (Epi8) into loop 1 of the hexon, enabling repeat administration to boost the anti-OprF immune response, and (ii) modification of the fiber gene to incorporate an integrin-binding RGD sequence to enhance gene delivery to antigen-presenting cells. Western analysis confirmed that AdOprF.RGD.Epi8 expresses OprF, contains Epi8 in the hexon protein, and enhances gene transfer to dendritic cells compared to AdOprF, a comparable Ad vector expressing OprF with an unmodified capsid. Intramuscular immunization of C57BL/6 mice with AdOprF.RGD.Epi8 resulted in the generation of anti-OprF antibodies at comparable levels to those induced following immunization with AdOprF, but immunization with AdOprF.RGD.Epi8 was associated with increased CD4 and CD8 gamma interferon T-cell responses against OprF as well as increased survival against lethal pulmonary challenge with agar-encapsulated P. aeruginosa. Importantly, repeat administration of AdOprF.RGD.Epi8 resulted in boosting of the humoral anti-OprF response as well as increased protection, whereas no boosting could be achieved with repeat administration of AdOprF. This suggests that the capsid-modified AdOprF.RGD.Epi8 vector is a more effective immunogen compared to a comparable wild-type Ad capsid, making it a good candidate for an anti-P. aeruginosa vaccine.
Collapse
|
24
|
Ulasov IV, Rivera AA, Han Y, Curiel DT, Zhu ZB, Lesniak MS. Targeting adenovirus to CD80 and CD86 receptors increases gene transfer efficiency to malignant glioma cells. J Neurosurg 2007; 107:617-27. [PMID: 17886563 DOI: 10.3171/jns-07/09/0617] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECT Gene therapy protocols for malignant gliomas utilize adenoviral vectors that rely almost exclusively on the adenovirus serotype 5 (Ad5) backbone. The authors have previously shown that chimeric vectors that bind to the Ad3 receptor, or CD46, increase the transduction efficiency of malignant brain tumors. In light of the debate regarding the efficacy of CD46 compared with CD80/CD86 in binding Ad3 virions, the authors now examine the expression and transduction efficiency of Ad5/3 chimeras that bind via CD80/CD86. METHODS The authors first analyzed CD80/CD86 expression in glioma cell lines. They then used three replication-defective vectors containing a luciferase reporter gene: Ad5/3 (containing the tail and shaft domain of Ad5 and the knob domain of Ad3); Ad3/5 (containing the tail of Ad5, shaft of Ad3, and knob of Ad5); and Ad3/3 (containing the tail of Ad5, shaft of Ad3, and knob of Ad3). These vectors were analyzed both in vitro and in vivo against malignant glioma cells. To examine further the effect of Ad5/3 fiber modification, the authors created an oncolytic vector, conditionally replicative Ad5/3 (CRAd5/3). RESULTS The Ad5/3 vector showed a 10- to 100-fold enhanced transduction efficiency of malignant glioma compared with replication-defective wild-type adenovirus (reAd5) (p < 0.05). Moreover the use of Ad5/3 reduced transgene expression by more than 90% in normal human brain cells compared with reAd5. Finally, the use of CRAd5/3 inhibited tumor cell proliferation by 43% more than replication-competent wild-type virus in vitro (p < 0.05). CONCLUSIONS The results of this study demonstrate that the Ad5/3 vector offers superior transduction efficiency and low toxicity in the setting of brain tumors, and therefore represents a potential new approach to gene therapy for malignant gliomas.
Collapse
Affiliation(s)
- Ilya V Ulasov
- Division of Neurosurgery, The University of Chicago, Chicago, Illinois 60637, USA
| | | | | | | | | | | |
Collapse
|
25
|
Gall JGD, Lizonova A, EttyReddy D, McVey D, Zuber M, Kovesdi I, Aughtman B, King CR, Brough DE. Rescue and production of vaccine and therapeutic adenovirus vectors expressing inhibitory transgenes. Mol Biotechnol 2007; 35:263-73. [PMID: 17652790 DOI: 10.1007/bf02686012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 12/26/2022]
Abstract
Expression of certain transgenes from an adenovirus vector can be deleterious to its own replication. This can result in the inhibition of virus rescue, reduced viral yields, or, in the worst case, make it impossible to construct a vector expressing the inhibiting transgene product. A gene regulation system based on the tet operon was used to allow the rescue and efficient growth of adenovectors that express transgenes to high levels. A key advantage to this system is that repression of transgene expression is mediated by the packaging cell line, thus, expression of regulatory products from the adenovector are not required. This provides a simple, broadly applicable system wherein transgene repression is constitutive during vector rescue and growth and there is no effect on adenovector-mediated expression of gene products in transduced cells. Several high-level expression vectors based on first- and second-generation adenovectors were rescued and produced to high titer that otherwise could not be grown. Yields of adenovectors expressing inhibitory transgene products were increased, and the overgrowth of cultures by adenovectors with nonfunctional expression cassettes was prevented. The gene regulation system is a significant advancement for the development of adenovirus vectors for vaccine and other gene transfer applications.
Collapse
Affiliation(s)
- Jason G D Gall
- GenVec, Inc. 65 West Watkins Mill Rd, Gaithersburg MD 20878, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Di Paolo NC, Kalyuzhniy O, Shayakhmetov DM. Fiber shaft-chimeric adenovirus vectors lacking the KKTK motif efficiently infect liver cells in vivo. J Virol 2007; 81:12249-59. [PMID: 17855526 PMCID: PMC2168974 DOI: 10.1128/jvi.01584-07] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The molecular mechanisms governing the infectivity of adenovirus (Ad) toward specific cell and tissue types in vivo remain poorly understood. The direct Ad binding to hepatic heparan sulfate proteoglycans via the KKTK motif within the fiber shaft domain was suggested to be the major mechanism of Ad liver cell infection in vivo. Here, we describe the generation and in vitro and in vivo infectivity studies of Ad5-based vectors possessing long Ad31- or Ad41-derived fiber shaft domains, which lack the KKTK motif. We found that all the critical early steps of Ad infection, including attachment to the cellular receptor, internalization, and virus genome transfer into the nucleus, occurred with similar levels of efficiency for fiber shaft-chimeric vectors and unmodified Ad5. Upon intravenous delivery into mice, fiber shaft-chimeric vectors accumulated in liver tissue, transduced liver cells, and induced the production of proinflammatory cytokines (tumor necrosis factor alpha and interleukin-6) and the chemokine monocyte chemoattractant protein 1 at levels indistinguishable from those observed for Ad5. Thus, our data provide evidence that the Ad5 fiber shaft amino acid sequence does not play any substantial role in determining adenovirus infectivity toward hepatic cells in vivo. The data obtained contribute to improving our understanding of the molecular mechanisms determining Ad infectivity and biodistribution in vivo and may aid in designing novel Ad-based vectors for gene therapy applications.
Collapse
Affiliation(s)
- Nelson C Di Paolo
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, WA 98195-7720, USA
| | | | | |
Collapse
|
27
|
Hesse A, Kosmides D, Kontermann RE, Nettelbeck DM. Tropism modification of adenovirus vectors by peptide ligand insertion into various positions of the adenovirus serotype 41 short-fiber knob domain. J Virol 2006; 81:2688-99. [PMID: 17192304 PMCID: PMC1865974 DOI: 10.1128/jvi.02722-06] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Recombinant adenoviruses have emerged as promising agents in therapeutic gene transfer, genetic vaccination, and viral oncolysis. Therapeutic applications of adenoviruses, however, would benefit substantially from targeted virus cell entry, for example, into cancer or immune cells, as opposed to the broad tropism that adenoviruses naturally possess. Such tropism modification of adenoviruses requires the deletion of their natural cell binding properties and the incorporation of cell binding ligands. The short fibers of subgroup F adenoviruses have recently been suggested as a tool for genetic adenovirus detargeting based on the reduced infectivity of corresponding adenovectors with chimeric fibers in vitro and in vivo. The goal of our study was to determine functional insertion sites for peptide ligands in the adenovirus serotype 41 (Ad41) short fiber knob. With a model peptide, CDCRGDCFC, we could demonstrate that ligand incorporation into three of five analyzed loops of the knob, namely, EG, HI, and IJ, is feasible without a loss of fiber trimerization. The resulting adenovectors showed enhanced infectivity for various cell types, which was superior to that of viruses with the same peptide fused to the fiber C terminus. Strategies to further augment gene transfer efficacy by extension of the fiber shaft, insertion of tandem copies of the ligand peptide, or extension of the ligand-flanking linkers failed, indicating that precise ligand positioning is pivotal. Our study establishes that internal ligand incorporation into a short-shafted adenovirus fiber is feasible and suggests the Ad41 short fiber with ligand insertion into the top (IJ loop) or side (EG and HI loops) of the knob domain as a novel platform for genetic targeting of therapeutic adenoviruses.
Collapse
Affiliation(s)
- Andrea Hesse
- Virotherapy Lab, Department of Dermatology, University Hospital Erlasngen, Hartmannstrasse 14, Erlangen, Germany
| | | | | | | |
Collapse
|
28
|
Lemiale F, Haddada H, Nabel GJ, Brough DE, King CR, Gall JGD. Novel adenovirus vaccine vectors based on the enteric-tropic serotype 41. Vaccine 2006; 25:2074-84. [PMID: 17250935 PMCID: PMC2584667 DOI: 10.1016/j.vaccine.2006.11.025] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2006] [Revised: 11/06/2006] [Accepted: 11/13/2006] [Indexed: 10/23/2022]
Abstract
Replication-defective adenovirus vectors, primarily developed from serotype 5 (Ad5) viruses, have been widely used for gene transfer and vaccination approaches. Vectors based on other serotypes of adenovirus could be used in conjunction with, or in place of, Ad5 vectors. In this study, Ad41, an enteric adenovirus usually described as 'non-cultivable' or 'fastidious,' has been successfully cloned, rescued and propagated on 293-ORF6 cells. The complementation capabilities of this cell line allow generation of Ad41 vectors at titers comparable to those obtained for Ad5 vectors. Mice immunized with an Ad41 vector containing an HIV envelope (Env) gene mounted anti-Env cellular and humoral immune responses. Ad41-Env vectors appear to be particularly attractive when used in heterologous prime-boost regimens, where they induce significantly higher cellular immune responses to HIV-Env than Ad5-based regimens. Ad41-based constructs are attractive vaccine vectors alone or in combination with Ad5 adenovectors, since each vector type can provide circumvention of pre-existing immunity to the other.
Collapse
Affiliation(s)
- Franck Lemiale
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, Maryland 20892
| | - Hedi Haddada
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, Maryland 20892
| | - Gary J. Nabel
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, Maryland 20892
| | | | | | - Jason G. D. Gall
- GenVec, Inc. Gaithersburg, Maryland, USA, 20878
- Corresponding author. 65 West Watkins Mill Road, Gaithersburg, MD, USA, 20878.
| |
Collapse
|
29
|
Henning P, Lundgren E, Carlsson M, Frykholm K, Johannisson J, Magnusson MK, Tång E, Franqueville L, Hong SS, Lindholm L, Boulanger P. Adenovirus type 5 fiber knob domain has a critical role in fiber protein synthesis and encapsidation. J Gen Virol 2006; 87:3151-3160. [PMID: 17030847 DOI: 10.1099/vir.0.81992-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Adenovirus serotype 5 (Ad5) vectors carrying knobless fibers designed to remove their natural tropism were found to have a lower fiber content than recombinant Ad5 with wild-type (WT) capsid, implying a role for the knob-coding sequence or/and the knob domain in fiber encapsidation. Experimental data using a variety of fiber gene constructs showed that the defect did not occur at the fiber mRNA level, but at the protein level. Knobless fiber proteins were found to be synthesized at a significant slower rate compared with knob-carrying fibers, and the trimerization process of knobless fibers paralleled their slow rate of synthesis. A recombinant Ad5 diploid for the fiber gene (referred to as Ad5/R7-ZZwt/E1 : WT-fiber) was constructed to analyse the possible rescue of the knobless low-fiber-content phenotype by co-expression of WT fiber. Ad5/R7-ZZwt/E1 : WT-fiber contained a knobless fiber gene in its natural location (L5) in the viral genome and an additional WT fiber gene in an ectopic position in E1. Knobless fiber was still synthesized at low levels compared with the co-expressed E1 : WT fiber and the recovery of the two fiber species in virus progeny reflected their respective amounts in the infected cells. Our results suggested that deletion of the fiber knob domain had a negative effect on the translation of the fiber mRNA and on the intracellular concentration of fiber protein. They also suggested that the knob control of fiber protein synthesis and encapsidation occurred as aciseffect, which was not modified by WT fiber protein providedin transby the same Ad5 genome.
Collapse
Affiliation(s)
- Petra Henning
- Institute for Biomedicine, Department of Microbiology and Immunology, University of Göteborg, PO Box 435, SE 40530 Göteborg, Sweden
- Got-A-Gene AB, Östra Kyviksvägen 18, SE 42930 Kullavik, Sweden
| | - Emma Lundgren
- Got-A-Gene AB, Östra Kyviksvägen 18, SE 42930 Kullavik, Sweden
| | | | | | | | - Maria K Magnusson
- Institute for Biomedicine, Department of Microbiology and Immunology, University of Göteborg, PO Box 435, SE 40530 Göteborg, Sweden
- Got-A-Gene AB, Östra Kyviksvägen 18, SE 42930 Kullavik, Sweden
| | - Erika Tång
- Got-A-Gene AB, Östra Kyviksvägen 18, SE 42930 Kullavik, Sweden
| | - Laure Franqueville
- Laboratoire de Virologie et Pathogénèse Virale, Université Claude Bernard de Lyon and CNRS UMR-5537, Faculté de Médecine RTH Laennec, 7 Rue Guillaume Paradin, 69372 Lyon Cedex 08, France
| | - Saw See Hong
- Laboratoire de Virologie et Pathogénèse Virale, Université Claude Bernard de Lyon and CNRS UMR-5537, Faculté de Médecine RTH Laennec, 7 Rue Guillaume Paradin, 69372 Lyon Cedex 08, France
| | - Leif Lindholm
- Got-A-Gene AB, Östra Kyviksvägen 18, SE 42930 Kullavik, Sweden
| | - Pierre Boulanger
- Laboratoire de Virologie Médicale, Domaine Rockefeller, Hospices Civils de Lyon, 8 Avenue Rockefeller, 69373 Lyon Cedex 08, France
- Laboratoire de Virologie et Pathogénèse Virale, Université Claude Bernard de Lyon and CNRS UMR-5537, Faculté de Médecine RTH Laennec, 7 Rue Guillaume Paradin, 69372 Lyon Cedex 08, France
| |
Collapse
|
30
|
Lu ZZ, Ni F, Hu ZB, Wang L, Wang H, Zhang QW, Huang WR, Wu CT, Wang LS. Efficient gene transfer into hematopoietic cells by a retargeting adenoviral vector system with a chimeric fiber of adenovirus serotype 5 and 11p. Exp Hematol 2006; 34:1171-82. [PMID: 16939810 DOI: 10.1016/j.exphem.2006.05.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2006] [Revised: 04/17/2006] [Accepted: 05/03/2006] [Indexed: 12/24/2022]
Abstract
OBJECTIVE Adenoviral vectors (Ad) were widely used in gene therapy and study of gene function, but the commonly used serotype 5 adenovirus-based vectors (Ad5) could poorly transduce hematopoietic cells because of low expression of viral receptors on these cells. To overcome this limitation, we developed a retargeting adenovector with a chimeric fiber of Ad5 and Ad11p (Ad5F11p) and evaluated its gene transfer ability in hematopoietic cells. MATERIALS AND METHODS An Ad11p fiber pseudotyped Ad5 vector was generated by modifying the fiber gene of pAdEasy-1 backbone plasmid. Ad5F11p-GFP encoding enhanced green fluorescence protein (GFP) gene was transferred into human leukemic cell lines, primary leukemic cells, and CD34(+) hematopoietic cells. The gene transduction efficiency was determined by fluorescence-activated cell sorting assay. RESULTS More than 90% of U937 or K562 cells could be infected by Ad5F11p-GFP at a moderate multiplicity of infection (MOI). Ad5F11p-GFP is also significantly more effective than control Ad5-GFP in infection of primary myeloid leukemic cells. At 200 MOI, GFP-positive percentages of Ad5F11p-GFP transduced myeloid leukemic cells range from 10.58% to 92.63% with a median of 28.65%. Ad5F11p-GFP could transduce about 50% human hematopoietic stem/progenitor (CD34(+)) cells, while Ad5-GFP could transduce <15% at 200 MOI. CD46 was reported to be the receptor of Ad11p. Our data suggest that CD46 participates in the process of Ad5F11p-GFP infection but is not the unique molecule determining its gene transfer efficiency of host cells. CONCLUSION We established a retargeting adenovector system, which could infect hematopoietic cells effectively and would benefit research work on Ad tropism.
Collapse
Affiliation(s)
- Zhuo-Zhuang Lu
- Department of Experimental Hematology, Beijing Institute of Radiation Medicine, Beijing, P.R. China
| | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Schoggins JW, Falck-Pedersen E. Fiber and penton base capsid modifications yield diminished adenovirus type 5 transduction and proinflammatory gene expression with retention of antigen-specific humoral immunity. J Virol 2006; 80:10634-44. [PMID: 16943295 PMCID: PMC1641751 DOI: 10.1128/jvi.01359-06] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Fiber and penton base capsid proteins of adenovirus type 5 (Ad5) mediate a well-characterized two-step entry pathway in permissive tissue culture cell lines. Fiber binds with high affinity to the cell surface coxsackievirus-and-adenovirus receptor (CAR), and penton base facilitates viral internalization by binding alphav integrins through an RGD motif. In vivo, the entry pathway is complicated by interactions of capsid proteins with additional cell surface molecules and blood factors. When administered systemically in mice, adenovirus vectors (Adv) localize primarily to hepatic tissue, resulting in efficient gene transduction and potent activation of the host antiviral immune response. The goal of the present study was to detarget Adv uptake through fiber and penton base capsid protein manipulations and determine how detargeted vectors influence transduction efficiency, inflammatory activation, and activation of the adaptive arm of the immune system. By manipulating fiber and the penton base, we have generated highly detargeted vectors (up to 1,200-fold reduction in transgene expression in vivo) with reduced macrophage stimulatory activity in vitro and in vivo. In spite of the diminished transduction and macrophage activation, the detargeted vectors induce strong neutralizing immunity as well as efficient antitransgene antibody. Three of the modified vectors produce antitransgene humoral immunity at levels that exceed or are equal to that seen with an unmodified Ad5-based vector. The fiber-pseudotyped and penton base constructs with RGD deleted have attributes that could be important enhancements in a number of vaccine applications.
Collapse
Affiliation(s)
- John W Schoggins
- Weill Medical College of Cornell University, Department of Microbiology and Immunology Box 62, 1300 York Ave., New York, NY 10021, USA
| | | |
Collapse
|
32
|
Emile Gras JC, Verkuijlen P, Frants RR, Havekes LM, van Berkel TJC, Biessen EAL, van Dijk KW. Specific and efficient targeting of adenovirus vectors to macrophages: application of a fusion protein between an adenovirus-binding fragment and avidin, linked to a biotinylated oligonucleotide. J Gene Med 2006; 8:668-78. [PMID: 16532513 DOI: 10.1002/jgm.895] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND The application of serotype 5 adenoviruses (Ad5) in macrophages is hampered by the absence of the endogenous coxsackie adenovirus receptor (CAR). METHODS To overcome this limitation, we first generated a linker protein consisting of the virus-binding domain of CAR and the C-terminus of avidin. Second, to target macrophages, this linker protein was equipped with the biotinylated (bio) oligonucleotide dA6G10, which was previously shown to display a high affinity for the scavenger receptor A (SR-A). RESULTS As compared to nontargeted virus, the linker protein equipped with bio-dA6G10 showed a 500-fold increased reporter gene expression in mouse macrophage RAW264.7 cells. A linker protein equipped with a bio-dA16 control oligonucleotide was inactive. Moreover, the bio-dA6G10-equipped linker showed a 390-fold increased luciferase expression in the macrophage cell line J774 and 276- and 150-fold increased reporter gene expression in primary peritoneal and bone marrow (BM)-derived macrophages, respectively. Using BM-derived macrophages from SR-A knockout mice, it was shown that the dA6G10-mediated uptake is predominantly SR-A-mediated. CONCLUSIONS Thus, we have developed a novel tool to link biotinylated ligands to a virus-binding fragment of CAR and have exploited this linker protein to extend the applicability of Ad5 to infect transformed and primary macrophages.
Collapse
Affiliation(s)
- J C Emile Gras
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | | | | | | | | | | | | |
Collapse
|
33
|
Lecollinet S, Gavard F, Havenga MJE, Spiller OB, Lemckert A, Goudsmit J, Eloit M, Richardson J. Improved gene delivery to intestinal mucosa by adenoviral vectors bearing subgroup B and d fibers. J Virol 2006; 80:2747-59. [PMID: 16501084 PMCID: PMC1395461 DOI: 10.1128/jvi.80.6.2747-2759.2006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
A major obstacle to successful oral vaccination is the lack of antigen delivery systems that are both safe and highly efficient. Conventional replication-incompetent adenoviral vectors, derived from human adenoviruses of subgroup C, are poorly efficient in delivering genetic material to differentiated intestinal epithelia. To date, 51 human adenovirus serotypes have been identified and shown to recognize different cellular receptors with different tissue distributions. This natural diversity was exploited in the present study to identify suitable adenoviral vectors for efficient gene delivery to the human intestinal epithelium. In particular, we compared the capacities of a library of adenovirus type 5-based vectors pseudotyped with fibers of several human serotypes for transduction, binding, and translocation toward the basolateral pole in human and murine tissue culture models of differentiated intestinal epithelia. In addition, antibody-based inhibition was used to gain insight into the molecular interactions needed for efficient attachment. We found that vectors differing merely in their fiber proteins displayed vastly different capacities for gene transfer to differentiated human intestinal epithelium. Notably, vectors bearing fibers derived from subgroup B and subgroup D serotypes transduced the apical pole of human epithelium with considerably greater efficiency than a subgroup C vector. Such efficiency was correlated with the capacity to use CD46 or sialic acid-containing glycoconjugates as opposed to CAR as attachment receptors. These results suggest that substantial gains could be made in gene transfer to digestive epithelium by exploiting the tropism of existing serotypes of human adenoviruses.
Collapse
Affiliation(s)
- S Lecollinet
- UMR01161 ENVA-INRA-AFSSA de Virologie, Ecole Nationale Vétérinaire d'Alfort, 7 Avenue du Général de Gaulle, 94704 Maisons-Alfort, France
| | | | | | | | | | | | | | | |
Collapse
|
34
|
Schoggins JW, Nociari M, Philpott N, Falck-Pedersen E. Influence of fiber detargeting on adenovirus-mediated innate and adaptive immune activation. J Virol 2005; 79:11627-37. [PMID: 16140740 PMCID: PMC1212603 DOI: 10.1128/jvi.79.18.11627-11637.2005] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The major adenovirus (Ad) capsid proteins hexon, penton, and fiber influence the efficiency and tropism of gene transduction by Ad vectors. Fiber is the high-affinity receptor binding protein that serves to mediate cell attachment in vitro when using coxsackie-adenovirus receptor (CAR)-containing cell lines. This contrasts with transduction efficiency in macrophages or dendritic cells that lack high concentrations of CAR. To determine how fiber influences gene transduction and immune activation in a murine model, we have characterized Ad type 5 (Ad5) vectors with two classes of chimeric fiber, CAR binding and non-CAR binding. In a systemic infection, Ad5 fiber contributes to DNA localization and vector transduction in hepatic tissue. However, the majority of vector localization is due to Ad5 fiber-specific functions distinct from CAR binding. CAR-directed transduction occurs but at a modest level. In contrast to CAR binding vectors, the F7 and F7F41S non-CAR-binding vectors demonstrate a 2-log decrease in hepatic transduction, with a 10-fold decrease in the amount of vector DNA localizing to the hepatic tissue. To characterize the innate response to early infection using fiber chimeric vectors, intrahepatic cytokine and chemokine mRNAs were quantified 5 hours postinfection. Tumor necrosis factor alpha mRNA levels resulting from Ad5 fiber infections were elevated compared to viruses expressing serotype 7 or 41 fiber. Levels of chemokine mRNA (gamma interferon-inducible protein 10, T-cell activation gene 3, and macrophage inflammatory protein 1beta) were 10- to 20-fold higher with CAR binding vectors (Ad5 and F41T) than with non-CAR-binding vectors (F7 and F7F41S). In spite of quantitative differences in vector localization and innate activation, fiber pseudotyping did not significantly change the outcome of anti-Ad adaptive immunity. All vectors were cleared with the same kinetics as wild-type Ad5 vectors, and each induced neutralizing antibody. Although non-CAR-binding vectors were impaired in transduction by nearly 2 orders of magnitude, the level of antitransgene immunity was the same for each of the vectors. Using primary bone marrow-derived macrophages and dendritic cells, we demonstrate that transduction, induction of cytokine/chemokine, and phenotypic maturation of these antigen-presenting cells are independent of fiber content. Our data support a model where fiber-mediated hepatic localization enhances innate responses to virus infection but minimally impacts on adaptive immunity.
Collapse
Affiliation(s)
- John W Schoggins
- Weill Medical College of Cornell University, Hearst Research Foundation, Department of Microbiology and Immunology Graduate Program, Box 62, 1300 York Ave., New York, New York 10021, USA
| | | | | | | |
Collapse
|
35
|
Kesisoglou F, Chamberlain JR, Schmiedlin-Ren P, Kaz A, Fleisher D, Roessler B, Zimmermann EM. Chimeric Ad5 Vectors Expressing the Short Fiber of Ad41 Show Reduced Affinity for Human Intestinal Epithelium. Mol Pharm 2005; 2:500-8. [PMID: 16323957 DOI: 10.1021/mp0498897] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Altering adenovirus tropism has attracted increased attention in recent years to improve gene delivery. We constructed a recombinant Ad5 vector carrying the non-CAR (coxsackievirus and adenovirus receptor) binding short fiber of enterotropic Ad41 (Ad5SHORT) and tested its transduction efficiency on enterocytes. Ad5SHORT was engineered, in high titers similar to the parent vector, by homologous recombination in Escherichia coli BJ5183 (recBC sbcBC) and propagated on C7 cells. Western blotting confirmed the presence of Ad41 short fiber on Ad5SHORT while lack of CAR-binding was evident by the low transduction of CHO-CAR cells. Transduction efficiency of enterocytes, the natural target tissue for the fiber-"donor" virus Ad41, was tested in human intestinal biopsy cultures and in Caco-2 cells, including ulcerative colitis tissue and mucosal wound healing models. Ad5SHORT exhibited up to 23-fold lower transduction levels compared to Ad5 in human intestinal biopsy cultures and up to 13-fold in the in vitro systems. The differences with the in vitro systems were more pronounced when less differentiated cells were used. These studies highlight the potential for using this chimeric Ad5/Ad41 vector as a scaffold for the development of retargeted adenoviral vectors. Finally, our results suggest that the short fiber does not appear to be mediating, at least by itself, the increased enterocyte affinity of Ad41.
Collapse
Affiliation(s)
- Filippos Kesisoglou
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of Michigan, Ann Arbor, Michigan 48109-1065, USA
| | | | | | | | | | | | | |
Collapse
|
36
|
Nicklin SA, Wu E, Nemerow GR, Baker AH. The influence of adenovirus fiber structure and function on vector development for gene therapy. Mol Ther 2005; 12:384-93. [PMID: 15993650 DOI: 10.1016/j.ymthe.2005.05.008] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2005] [Revised: 05/09/2005] [Accepted: 05/10/2005] [Indexed: 01/02/2023] Open
Abstract
The collective attributes of adenoviruses (Ads), including ease of accomplishing replication deficiency, readily achievable high titers, encoding of large expression cassettes, efficiency of gene delivery to most cell types, and well-characterized biology, have made Ads, particularly Ad serotype 5 (Ad 5), some of the most utilized vectors for gene delivery. In recent years, however, it has become apparent that additional aspects of basic Ad virology must be uncovered for this vector system to succeed in the clinic. While local gene delivery is generally efficient, the broad tropism of Ad 5 and its tendency to home to the liver after systemic administration have proved to be limitations for other therapeutic applications, such as the treatment of disseminated cancers and cardiovascular disease. This has refocused research into the biology of Ad capsid components, particularly the main tropism determinant, the fiber/penton base complex, and their influence on transduction of selected cell types in vivo.
Collapse
Affiliation(s)
- Stuart A Nicklin
- BHF Glasgow Cardiovascular Research Centre, Division of Cardiovascular and Medical Sciences, University of Glasgow, Church Street, Glasgow G11 6NT, UK
| | | | | | | |
Collapse
|
37
|
Pereboeva L, Komarova S, Mahasreshti PJ, Curiel DT. Fiber-mosaic adenovirus as a novel approach to design genetically modified adenoviral vectors. Virus Res 2005; 105:35-46. [PMID: 15325079 DOI: 10.1016/j.virusres.2004.04.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2004] [Revised: 04/05/2004] [Accepted: 04/22/2004] [Indexed: 11/22/2022]
Abstract
Genetic modification of the adenovirus (Ad) capsid is one of the successful strategies to achieve viral retargeting. However, it has been widely recognized that structural constraints imposed by viral proteins limit the number and nature of incorporated targeting ligands and often hamper viral propagation. To address this issue, we propose a genetic fiber-mosaic virus (having two distinct fibers in one viral particle) as a means to facilitate fiber modifications. Fiber-mosaic virus having tandem fibers: a wild type (wt) fiber and second adjunctive fiber, will utilize natural viral entry for the conventional propagation of the vectors whereas, adjunctive fiber will serve multiple potential purposes such as targeting, purification, or imaging of viral particles via genetic incorporation of the corresponding functional moieties. We generated the mosaic adenovirus vector encoding two fibers: wild-type and adjunctive fiber--Fiber-Fibritin (FF) and confirmed incorporation of FF in the mosaic viral particles. We investigated binding specificity of the mosaic virus and the possible interference of the two fibers during virus life cycle. Fiber-mosaic Ad attained new binding properties provided by the second fiber, while preserving the binding ability attributed to the wt fiber. Our results suggest that the two fibers being presented and structurally separated on the viral particle may also function separately as binding counterparts for virus attachment. Therefore, the mosaic setting will allow more flexibility in Ad retargeting approaches.
Collapse
Affiliation(s)
- Larisa Pereboeva
- Division of Human Gene Therapy, Department of Medicine, The Gene Therapy Center, University of Alabama at Birmingham, Birmingham, Al 35294, USA
| | | | | | | |
Collapse
|
38
|
Yun CO, Yoon AR, Yoo JY, Kim H, Kim M, Ha T, Kim GE, Kim H, Kim JH. Coxsackie and Adenovirus Receptor Binding Ablation Reduces Adenovirus Liver Tropism and Toxicity. Hum Gene Ther 2005; 16:248-61. [PMID: 15761264 DOI: 10.1089/hum.2005.16.248] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Human adenovirus-based vectors have emerged as a new promising vehicle for in vivo gene transfer-mediated therapy. However, the full potential of this methodology has not been fully realized because of the nonspecific tissue distribution of adenoviral vectors. Adenovirus infection is initiated by forming a complex between the fiber protein and a ubiquitously expressed host cell membrane protein, coxsackie B virus and adenovirus receptor (CAR). Therefore, ablating the adenovirus vector's ability to bind to the CAR is the first step in redirecting adenoviral tropism. To ablate CAR binding, we mutated the Bbeta sheet of the fiber knob, generating CAR-binding ablated replication-incompetent (dl-K420A-Z) and replication-competent (YKLK420A) adenoviral vectors. The in vitro transduction efficiency of dl-K420A-Z was significantly reduced in comparison to dl-LacZ carrying the wild-type fiber in CAR-positive cells but not in CAR-negative cells, suggesting that the mutation introduced in the Bbeta sheet of the fiber knob could disable the CAR-dependent transduction pathway. The in vivo transduction was also dramatically reduced in the liver and other organs for mice treated with dl-K420A-Z, compared with a cognate control vector, dl-LacZ. Concomitant with this attenuated gene transfer efficiency in vivo was a substantial reduction in the amount of general toxicity observed in the YKL-K420A-treated mice. Diminished toxicity was surmised from quantitative measurement of serum level of enzymes for liver and kidney function, hematologic chemistries, histopathology, and differences in lethality. Significant decrease in serum transaminases (alanine transferase [ALT] and aspartate transferase [AST]) was observed in mice treated with YKL-K420A. In addition, the lethality was lower in the YKLK420A- treated groups compared to the YKL-1-treated groups at all doses examined. Furthermore, the hepatopathologic analysis revealed that YKL-1 induced focal zonal necrosis and hepatocyte degeneration, while YKL-K420A induced mild spotty necrosis. In summary, this decreased vector tropism of CAR-binding ablated adenoviruses in normal tissues may increase the amount of virus available for infecting tumor cells and thus increase the antitumor efficacy with fewer unwanted side effects.
Collapse
Affiliation(s)
- Chae-Ok Yun
- Brain Korea 21 Project for Medical Science, Institute for Cancer Research, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, 120-752, Korea
| | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Denby L, Work LM, Graham D, Hsu C, von Seggern DJ, Nicklin SA, Baker AH. Adenoviral Serotype 5 Vectors Pseudotyped with Fibers from Subgroup D Show Modified TropismIn VitroandIn Vivo. Hum Gene Ther 2004; 15:1054-64. [PMID: 15610606 DOI: 10.1089/hum.2004.15.1054] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Adenovirus (Ad5) serotype 5 vectors are commonly used for gene transfer. Preclinical studies have shown that their application to systemic gene delivery, however, is limited by their highly efficient uptake in the liver, principally mediated by receptor-binding sites on the fiber shaft and knob domain. Using Ad to target other sites in vivo requires vectors that lack hepatic tropism. We therefore sought to exploit Ad family diversity to isolate vectors that possessed poor hepatic tropism. We pseudotyped the fibers from Ad16 (subgroup B; Ad5/16), Ad19p (subgroup D; Ad5/19p), and Ad37 (subgroup D; Ad5/37) onto Ad5 capsids and assessed infectivity profiles in vitro in multiple cell types and in vivo in rats. In rat, mouse, and human hepatocytes, Ad5/19p and Ad5/37 both possessed a striking lack of hepatic cell infectivity compared with Ad5. Both vectors were, however, able to transduce human vascular endothelial and smooth muscle cells with efficiencies equal to or greater than that of nonmodified Ad5. We evaluated liver uptake in 12-week-old male rats after intravenous injection. In contrast to a vector with the wild-type Ad5 fiber, Ad5, both Ad5/19p and Ad5/37 produced significantly less virion accumulation (measured at 1 hr and 5 days) and transgene expression in the liver. Thus, Ad5/19p and Ad5/37 may be useful platforms for the development of targeted Ad vectors.
Collapse
Affiliation(s)
- Laura Denby
- Division of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow G11 6NT, United Kingdom
| | | | | | | | | | | | | |
Collapse
|
40
|
Denby L, Work LM, Graham D, Hsu C, Von Seggern DJ, Nicklin SA, Baker AH. Adenoviral Serotype 5 Vectors Pseudotyped with Fibers from Subgroup D Show Modified Tropism In Vitro and In Vivo. Hum Gene Ther 2004. [DOI: 10.1089/hum.2004.0.ft-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
41
|
Skog J, Edlund K, Widegren B, Salford LG, Wadell G, Mei YF. Efficient internalization into low-passage glioma cell lines using adenoviruses other than type 5: an approach for improvement of gene delivery to brain tumours. J Gen Virol 2004; 85:2627-2638. [PMID: 15302956 DOI: 10.1099/vir.0.80084-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
There is a need for improvement of the commonly used adenovirus vectors based on serotype 5. This study was performed on three adenovirus serotypes with a CAR-binding motif (Ad4p, Ad5p and Ad17p) and three non-CAR-binding serotypes (Ad11p, Ad16p and Ad21p). The capacity of these alternative adenovirus vector candidates to deliver DNA into low-passage glioma cell lines from seven different donors was evaluated. The non-CAR-binding serotype Ad16p was the most efficient serotype with regard to import of its DNA, as well as initiation of hexon protein expression. Ad16p established hexon expression in 60–80 % of the cell population in gliomas from all donors tested. The other non-CAR-binding serotypes, Ad11p and Ad21p, showed hexon expression in 25–60 and 40–80 % of cells, respectively. The corresponding figure for the best CAR-binding serotype, Ad5p, was only 25–65 %, indicating greater variability between cells from different donors than serotype Ad16p had. The other CAR-binding serotypes, Ad4p and Ad17p, were refractory to some of the gliomas, giving a maximum of only 45 and 40 % hexon expression, respectively, in the most permissive cells. Interestingly, the transduction capacity of the CAR-binding serotypes was not correlated to the level of CAR expression on the cells.
Collapse
Affiliation(s)
- Johan Skog
- Department of Virology, Umeå University, SE-901 85 Umeå, Sweden
| | - Karin Edlund
- Department of Virology, Umeå University, SE-901 85 Umeå, Sweden
| | - Bengt Widegren
- Department of Cell and Molecular Biology, Lund University, SE-223 62 Lund, Sweden
| | - Leif G Salford
- Department of Neurosurgery, Lund University Hospital, SE-221 85 Lund, Sweden
| | - Göran Wadell
- Department of Virology, Umeå University, SE-901 85 Umeå, Sweden
| | - Ya-Fang Mei
- Department of Virology, Umeå University, SE-901 85 Umeå, Sweden
| |
Collapse
|
42
|
Nicol CG, Graham D, Miller WH, White SJ, Smith TAG, Nicklin SA, Stevenson SC, Baker AH. Effect of adenovirus serotype 5 fiber and penton modifications on in vivo tropism in rats. Mol Ther 2004; 10:344-54. [PMID: 15294181 DOI: 10.1016/j.ymthe.2004.05.020] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2004] [Accepted: 05/12/2004] [Indexed: 11/22/2022] Open
Abstract
Sequestration of adenovirus serotype 5 (Ad5) in liver restricts its use for gene delivery to other target sites in vivo. To date, no studies have systematically assessed the impact of genetic capsid modifications on in vivo tropism in rats, an important preclinical model for many disease types. We evaluated a panel of Ad5 vectors with capsid mutations or pseudotyped with the short fiber from serotype 41 (Ad41s) for infectivity in Wistar Kyoto rats in vitro and systemically in vivo. In vitro studies demonstrated that both coxsackie and adenovirus receptor (CAR) and heparan sulfate proteoglycan (HSPG) binding were predominant predictors of Ad5 tropism. In vivo, neither CAR nor integrin mutations alone affected liver transduction. The HSPG-binding mutation alone moderately reduced rat liver transgene levels by 2-fold (P < 0.05). This was further substantially decreased by additional mutation of CAR binding (95-fold). Combining CAR and integrin mutations reduced transgene levels by >99% (509-fold, P < 0.01), an effect not observed in parallel experiments in mice and highly variable when studied further in an additional two strains of rat. Ad41s mediated very low liver transduction (58-fold lower than AdCTL). Moreover, CAR-binding mutants (KO1-containing) or pseudotyping 41s eliminated hemagglutination of rat and human red blood cells in vitro. This highlights some important potential species and strain differences dictating Ad5 tropism in vivo and identifies vectors that are substantially detargeted from rat liver in vivo.
Collapse
Affiliation(s)
- Campbell G Nicol
- Division of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow G11 6NT, United Kingdom
| | | | | | | | | | | | | | | |
Collapse
|
43
|
Balamotis MA, Huang K, Mitani K. Efficient delivery and stable gene expression in a hematopoietic cell line using a chimeric serotype 35 fiber pseudotyped helper-dependent adenoviral vector. Virology 2004; 324:229-37. [PMID: 15183069 DOI: 10.1016/j.virol.2004.03.030] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2004] [Revised: 02/10/2004] [Accepted: 03/26/2004] [Indexed: 11/25/2022]
Abstract
Certain human cell populations have remained difficult to infect with human adenovirus (Ad) serotype 5 because of their lack of coxsackievirus B-adenovirus receptor (CAR). Native adenovirus fiber compositions, although diverse, cannot infect all tissue types. Recently, a chimeric Ad5/35 fiber was created, which displays an altered tropism from Ad5. We incorporated this chimeric fiber into a helper-dependent (HD) adenovirus vector system and compared HD to E1-deleted (E1Delta) vectors by transgene expression, cell transduction efficiency, and cytotoxicity. K562 cells were infected approximately 50 times more efficiently with the chimeric Ad5/35 fiber compared with the Ad5 fiber. Short-term transgene expression was sustained longer from HD Ad5/35 than E1Delta Ad5/35 vector after in vitro infection of actively dividing K562 cells. Rapid loss of transgene expression from E1Delta Ad5/35 infection was not due to the loss of vector genomes, as determined by quantitative real-time PCR (QRT-PCR), or cytotoxicity, but rather through a putative silencing mechanism.
Collapse
Affiliation(s)
- Michael Andrew Balamotis
- Department of Microbiology, Immunology and Molecular Genetics, University of California-Los Angeles, Los Angeles, CA 90095-1747, USA
| | | | | |
Collapse
|
44
|
Vellinga J, Rabelink MJWE, Cramer SJ, van den Wollenberg DJM, Van der Meulen H, Leppard KN, Fallaux FJ, Hoeben RC. Spacers increase the accessibility of peptide ligands linked to the carboxyl terminus of adenovirus minor capsid protein IX. J Virol 2004; 78:3470-9. [PMID: 15016870 PMCID: PMC371045 DOI: 10.1128/jvi.78.7.3470-3479.2004] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The efficiency and specificity of gene transfer with human adenovirus (hAd)-derived gene transfer vectors would be improved if the native viral tropism could be modified. Here, we demonstrate that the minor capsid protein IX (pIX), which is present in 240 copies in the Ad capsid, can be exploited as an anchor for heterologous polypeptides. Protein IX-deleted hAd5 vectors were propagated in hAd5 helper cells expressing pIX variants, with heterologous carboxyl-terminal extensions of up to 113 amino acids in length. The extensions evaluated consist of alpha-helical spacers up to 75 A in length and to which peptide ligands were fused. The pIX variants were efficiently incorporated into the capsids of Ad particles. On intact particles, the MYC-tagged-pIX molecules were readily accessible to anti-MYC antibodies, as demonstrated by electron microscopic analyses of immunogold-labeled virus particles. The labeling efficiency improved with increasing spacer length, suggesting that the spacers lift and expose the ligand at the capsid surface. Furthermore, we found that the addition of an integrin-binding RGD motif to the pIX markedly stimulated the transduction of coxsackievirus group B and hAd receptor-deficient endothelioma cells, demonstrating the utility of pIX modification in gene transfer. Our data demonstrate that the minor capsid protein IX can be used as an anchor for the addition of polypeptide ligands to Ad particles.
Collapse
Affiliation(s)
- Jort Vellinga
- Department of Molecular Cell Biology, Leiden University Medical Centre, 2333 AL Leiden, The Netherlands
| | | | | | | | | | | | | | | |
Collapse
|
45
|
Akiyama M, Thorne S, Kirn D, Roelvink PW, Einfeld DA, King CR, Wickham TJ. Ablating CAR and Integrin Binding in Adenovirus Vectors Reduces Nontarget Organ Transduction and Permits Sustained Bloodstream Persistence Following Intraperitoneal Administration. Mol Ther 2004; 9:218-30. [PMID: 14759806 DOI: 10.1016/j.ymthe.2003.10.010] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2003] [Accepted: 10/06/2003] [Indexed: 11/17/2022] Open
Abstract
To create tumor-targeted Ad vectors, ablation of native CAR and integrin receptor binding is crucial to enhance the specificity of tumor transduction. Toward this aim, we have previously created base vectors in which binding to CAR (single-ablated) or to both CAR and integrins (double-ablated) has been ablated. In this study, the biodistribution of the conventional (CAR and integrin binding intact), single-ablated, and double-ablated vectors was evaluated following intraperitoneal administration. The mesothelial lining of the peritoneal organs was the principle site of CAR-dependent gene transfer by the conventional vector. Surprisingly, the single-ablated vector strongly transduced the liver parenchyma rather than the mesothelium, while the double-ablated vector did not significantly transduce the parenchyma or mesothelium. The high level of parenchymal transduction by the single-ablated vector suggested that it efficiently entered the bloodstream from the peritoneal cavity. Consistent with this hypothesis, a large proportion of active particles distributed and persisted in the bloodstream following intraperitoneal administration of either the single- or the double-ablated vector. The above results suggest that the double-ablated vector backbone may not only significantly improve targeting to cancers located in the peritoneal cavity, but may also significantly improve targeting to metastatic tumors located throughout the body by virtue of its enhanced bloodstream persistence.
Collapse
Affiliation(s)
- Masaki Akiyama
- FUSO Pharmaceutical Industries, Ltd., 2-3-30 MorinomiyaJoto, Osaka 536-8523, Japan
| | | | | | | | | | | | | |
Collapse
|