1
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Minetti A. Unlocking the potential of adeno-associated virus in neuroscience: a brief review. Mol Biol Rep 2024; 51:563. [PMID: 38647711 PMCID: PMC11035420 DOI: 10.1007/s11033-024-09521-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Accepted: 04/03/2024] [Indexed: 04/25/2024]
Abstract
Adeno-associated virus (AAV) has emerged as a pivotal tool in neuroscience research, owing to its remarkable versatility and efficiency in delivering genetic material to diverse cell types within the nervous system. This mini review aims to underscore the advanced applications of AAV vectors in neuroscience and their profound potential to revolutionize our understanding of brain function and therapeutic interventions for neurological disorders. By providing a concise overview of the latest developments and strategies employing AAV vectors, this review illuminates the transformative role of AAV technology in unraveling the complexities of neural circuits and paving the way for innovative treatments. Through elucidating the multifaceted capabilities of AAV-mediated gene delivery, this review underscores its pivotal role as a cornerstone in contemporary neuroscience research, promising remarkable insights into the intricacies of brain biology and offering new avenues for therapeutic intervention.
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Affiliation(s)
- Antea Minetti
- Neuroscience Institute, National Research Council (CNR), Pisa, Italy.
- Department of Biology, Unit of Cell and Developmental Biology, University of Pisa, Pisa, Italy.
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2
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Lopez-Gordo E, Chamberlain K, Riyad JM, Kohlbrenner E, Weber T. Natural Adeno-Associated Virus Serotypes and Engineered Adeno-Associated Virus Capsid Variants: Tropism Differences and Mechanistic Insights. Viruses 2024; 16:442. [PMID: 38543807 PMCID: PMC10975205 DOI: 10.3390/v16030442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 03/02/2024] [Accepted: 03/06/2024] [Indexed: 05/23/2024] Open
Abstract
Today, adeno-associated virus (AAV)-based vectors are arguably the most promising in vivo gene delivery vehicles for durable therapeutic gene expression. Advances in molecular engineering, high-throughput screening platforms, and computational techniques have resulted in a toolbox of capsid variants with enhanced performance over parental serotypes. Despite their considerable promise and emerging clinical success, there are still obstacles hindering their broader use, including limited transduction capabilities, tissue/cell type-specific tropism and penetration into tissues through anatomical barriers, off-target tissue biodistribution, intracellular degradation, immune recognition, and a lack of translatability from preclinical models to clinical settings. Here, we first describe the transduction mechanisms of natural AAV serotypes and explore the current understanding of the systemic and cellular hurdles to efficient transduction. We then outline progress in developing designer AAV capsid variants, highlighting the seminal discoveries of variants which can transduce the central nervous system upon systemic administration, and, to a lesser extent, discuss the targeting of the peripheral nervous system, eye, ear, lung, liver, heart, and skeletal muscle, emphasizing their tissue and cell specificity and translational promise. In particular, we dive deeper into the molecular mechanisms behind their enhanced properties, with a focus on their engagement with host cell receptors previously inaccessible to natural AAV serotypes. Finally, we summarize the main findings of our review and discuss future directions.
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3
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Theuerkauf SA, Herrera-Carrillo E, John F, Zinser LJ, Molina MA, Riechert V, Thalheimer FB, Börner K, Grimm D, Chlanda P, Berkhout B, Buchholz CJ. AAV vectors displaying bispecific DARPins enable dual-control targeted gene delivery. Biomaterials 2023; 303:122399. [PMID: 37992599 PMCID: PMC10721713 DOI: 10.1016/j.biomaterials.2023.122399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/10/2023] [Accepted: 11/10/2023] [Indexed: 11/24/2023]
Abstract
Precise delivery of genes to therapy-relevant cells is crucial for in vivo gene therapy. Receptor-targeting as prime strategy for this purpose is limited to cell types defined by a single cell-surface marker. Many target cells are characterized by combinations of more than one marker, such as the HIV reservoir cells. Here, we explored the tropism of adeno-associated viral vectors (AAV2) displaying designed ankyrin repeat proteins (DARPins) mono- and bispecific for CD4 and CD32a. Cryo-electron tomography revealed an unaltered capsid structure in the presence of DARPins. Surprisingly, bispecific AAVs transduced CD4/CD32a double-positive cells at much higher efficiencies than single-positive cells, even if present in low amounts in cell mixtures or human blood. This preference was confirmed when vector particles were systemically administered into mice. Cell trafficking studies revealed an increased cell entry rate for bispecific over monospecific AAVs. When equipped with an HIV genome-targeting CRISPR/Cas cassette, the vectors prevented HIV replication in T cell cultures. The data provide proof-of-concept for high-precision gene delivery through tandem-binding regions on AAV. Reminiscent of biological products following Boolean logic AND gating, the data suggest a new option for receptor-targeted vectors to improve the specificity and safety of in vivo gene therapy.
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Affiliation(s)
- Samuel A Theuerkauf
- Gene Therapy and Molecular Biotechnology, Paul-Ehrlich-Institut, Langen, Germany
| | | | - Fabian John
- Gene Therapy and Molecular Biotechnology, Paul-Ehrlich-Institut, Langen, Germany; Frankfurt Cancer Institute, Goethe University, Frankfurt, Germany
| | - Luca J Zinser
- Gene Therapy and Molecular Biotechnology, Paul-Ehrlich-Institut, Langen, Germany
| | | | - Vanessa Riechert
- Gene Therapy and Molecular Biotechnology, Paul-Ehrlich-Institut, Langen, Germany
| | - Frederic B Thalheimer
- Gene Therapy and Molecular Biotechnology, Paul-Ehrlich-Institut, Langen, Germany; Frankfurt Cancer Institute, Goethe University, Frankfurt, Germany
| | - Kathleen Börner
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Heidelberg, Germany; BioQuant, Heidelberg University, Heidelberg, Germany; German Center for Infection Research (DZIF), Heidelberg, Germany
| | - Dirk Grimm
- BioQuant, Heidelberg University, Heidelberg, Germany; German Center for Infection Research (DZIF), Heidelberg, Germany; Department of Infectious Diseases/Virology, Section Viral Vector Technologies, Heidelberg University Hospital, Heidelberg, Germany; German Center for Cardiovascular Research (DZHK), Heidelberg, Germany
| | - Petr Chlanda
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Heidelberg, Germany; BioQuant, Heidelberg University, Heidelberg, Germany; Schaller Research Groups, Heidelberg University, Heidelberg, Germany
| | | | - Christian J Buchholz
- Gene Therapy and Molecular Biotechnology, Paul-Ehrlich-Institut, Langen, Germany; Frankfurt Cancer Institute, Goethe University, Frankfurt, Germany.
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4
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Bentler M, Hardet R, Ertelt M, Rudolf D, Kaniowska D, Schneider A, Vondran FW, Schoeder CT, Delphin M, Lucifora J, Ott M, Hacker UT, Adriouch S, Büning H. Modifying immune responses to adeno-associated virus vectors by capsid engineering. Mol Ther Methods Clin Dev 2023; 30:576-592. [PMID: 37693943 PMCID: PMC10485635 DOI: 10.1016/j.omtm.2023.08.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 08/18/2023] [Indexed: 09/12/2023]
Abstract
De novo immune responses are considered major challenges in gene therapy. With the aim to lower innate immune responses directly in cells targeted by adeno-associated virus (AAV) vectors, we equipped the vector capsid with a peptide known to interfere with Toll-like receptor signaling. Specifically, we genetically inserted in each of the 60 AAV2 capsid subunits the myeloid differentiation primary response 88 (MyD88)-derived peptide RDVLPGT, known to block MyD88 dimerization. Inserting the peptide neither interfered with capsid assembly nor with vector production yield. The novel capsid variant, AAV2.MB453, showed superior transduction efficiency compared to AAV2 in human monocyte-derived dendritic cells and in primary human hepatocyte cultures. In line with our hypothesis, AAV2.MB453 and AAV2 differed regarding innate immune response activation in primary human cells, particularly for type I interferons. Furthermore, mice treated with AAV2.MB453 showed significantly reduced CD8+ T cell responses against the transgene product for different administration routes and against the capsid following intramuscular administration. Moreover, humoral responses against the capsid were mitigated as indicated by delayed IgG2a antibody formation and an increased NAb50. To conclude, insertion of the MyD88-derived peptide into the AAV2 capsid improved early steps of host-vector interaction and reduced innate and adaptive immune responses.
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Affiliation(s)
- Martin Bentler
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
| | - Romain Hardet
- University of Rouen, INSERM, U1234, Pathophysiology Autoimmunity and Immunotherapy (PANTHER), Normandie University, 76000 Rouen, France
| | - Moritz Ertelt
- Institute for Drug Discovery, University of Leipzig Medical Center, 04103 Leipzig, Germany
- Center for Scalable Data Analytics and Artificial Intelligence (ScaDS.AI), Dresden/Leipzig, Germany
| | - Daniela Rudolf
- Laboratory for Vector Based Immunotherapy, Fraunhofer Institute for Cell Therapy and Immunology (IZI), 04103 Leipzig, Germany
| | - Dorota Kaniowska
- Laboratory for Vector Based Immunotherapy, Fraunhofer Institute for Cell Therapy and Immunology (IZI), 04103 Leipzig, Germany
- Department of Medicine II, University Cancer Center Leipzig (UCCL), University of Leipzig Medical Center, 04103 Leipzig, Germany
| | - Andreas Schneider
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
| | - Florian W.R. Vondran
- ReMediES, Department of General, Visceral and Transplant Surgery, Hannover Medical School, 30625 Hannover, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
| | - Clara T. Schoeder
- Institute for Drug Discovery, University of Leipzig Medical Center, 04103 Leipzig, Germany
| | - Marion Delphin
- CIRI, Centre International de Recherche en Infectiologie, Université de Lyon, Inserm U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, 69007 Lyon, France
| | - Julie Lucifora
- CIRI, Centre International de Recherche en Infectiologie, Université de Lyon, Inserm U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, 69007 Lyon, France
| | - Michael Ott
- Department of Gastroenterology, Hepatology, and Endocrinology, Hannover Medical School, 30625 Hannover, Germany
| | - Ulrich T. Hacker
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
- Laboratory for Vector Based Immunotherapy, Fraunhofer Institute for Cell Therapy and Immunology (IZI), 04103 Leipzig, Germany
- Department of Medicine II, University Cancer Center Leipzig (UCCL), University of Leipzig Medical Center, 04103 Leipzig, Germany
| | - Sahil Adriouch
- University of Rouen, INSERM, U1234, Pathophysiology Autoimmunity and Immunotherapy (PANTHER), Normandie University, 76000 Rouen, France
| | - Hildegard Büning
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
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5
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Masri S, Carré L, Jaulin N, Vandamme C, Couzinié C, Guy-Duché A, Dupont JB, Pereira A, Charpentier E, David L, Gernoux G, Guilbaud M, Adjali O. Transcriptomic Analysis Reveals the Inability of Recombinant AAV8 to Activate Human Monocyte-Derived Dendritic Cells. Int J Mol Sci 2023; 24:10447. [PMID: 37445621 DOI: 10.3390/ijms241310447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 06/13/2023] [Accepted: 06/14/2023] [Indexed: 07/15/2023] Open
Abstract
Recombinant Adeno-Associated Virus (rAAV) is considered as one of the most successful and widely used viral vectors for in vivo gene therapy. However, host immune responses to the vector and/or the transgene product remain a major hurdle to successful AAV gene transfer. In contrast to antivector adaptive immunity, the initiation of the innate immunity towards rAAV is still poorly understood but is directly dependent on the interaction between the viral vector and innate immune cells. Here, we used a quantitative transcriptomic-based approach to determine the activation of inflammatory and anti-viral pathways after rAAV8-based infection of monocyte-derived dendritic cells (moDCs) obtained from 12 healthy human donors. We have shown that rAAV8 particles are efficiently internalized, but that this uptake does not induce any detectable transcriptomic change in moDCs in contrast to an adenoviral infection, which upregulates anti-viral pathways. These findings suggest an immunologically favorable profile for rAAV8 serotype with regard to in vitro activation of moDC model. Transcriptomic analysis of rAAV-infected innate immune cells is a powerful method to determine the ability of the viral vector to be seen by these sensor cells, which remains of great importance to better understand the immunogenicity of rAAV vectors and to design immune-stealth products.
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Affiliation(s)
- Samer Masri
- Nantes Université, CHU Nantes, INSERM, TaRGeT-Translational Research in Gene Therapy, UMR 1089, F-44200 Nantes, France
| | - Laure Carré
- Nantes Université, CHU Nantes, INSERM, TaRGeT-Translational Research in Gene Therapy, UMR 1089, F-44200 Nantes, France
| | - Nicolas Jaulin
- Nantes Université, CHU Nantes, INSERM, TaRGeT-Translational Research in Gene Therapy, UMR 1089, F-44200 Nantes, France
| | - Céline Vandamme
- Nantes Université, CHU Nantes, INSERM, TaRGeT-Translational Research in Gene Therapy, UMR 1089, F-44200 Nantes, France
| | - Célia Couzinié
- Nantes Université, CHU Nantes, INSERM, TaRGeT-Translational Research in Gene Therapy, UMR 1089, F-44200 Nantes, France
| | - Aurélien Guy-Duché
- Nantes Université, CHU Nantes, INSERM, TaRGeT-Translational Research in Gene Therapy, UMR 1089, F-44200 Nantes, France
| | - Jean-Baptiste Dupont
- Nantes Université, CHU Nantes, INSERM, TaRGeT-Translational Research in Gene Therapy, UMR 1089, F-44200 Nantes, France
| | - Allwyn Pereira
- Nantes Université, CHU Nantes, INSERM, TaRGeT-Translational Research in Gene Therapy, UMR 1089, F-44200 Nantes, France
| | - Eric Charpentier
- Nantes Université, CHU Nantes, CNRS, INSERM, SFR Santé, UMS 3556, UMS016, F-44000 Nantes, France
| | - Laurent David
- Nantes Université, CHU Nantes, INSERM, Center for Research in Transplantation and Translational Immunology, UMR 1064, ITUN, F-44000 Nantes, France
| | - Gwladys Gernoux
- Nantes Université, CHU Nantes, INSERM, TaRGeT-Translational Research in Gene Therapy, UMR 1089, F-44200 Nantes, France
| | - Mickaël Guilbaud
- Nantes Université, CHU Nantes, INSERM, TaRGeT-Translational Research in Gene Therapy, UMR 1089, F-44200 Nantes, France
| | - Oumeya Adjali
- Nantes Université, CHU Nantes, INSERM, TaRGeT-Translational Research in Gene Therapy, UMR 1089, F-44200 Nantes, France
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6
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Golm SK, Hübner W, Müller KM. Fluorescence Microscopy in Adeno-Associated Virus Research. Viruses 2023; 15:v15051174. [PMID: 37243260 DOI: 10.3390/v15051174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/02/2023] [Accepted: 05/07/2023] [Indexed: 05/28/2023] Open
Abstract
Research on adeno-associated virus (AAV) and its recombinant vectors as well as on fluorescence microscopy imaging is rapidly progressing driven by clinical applications and new technologies, respectively. The topics converge, since high and super-resolution microscopes facilitate the study of spatial and temporal aspects of cellular virus biology. Labeling methods also evolve and diversify. We review these interdisciplinary developments and provide information on the technologies used and the biological knowledge gained. The emphasis lies on the visualization of AAV proteins by chemical fluorophores, protein fusions and antibodies as well as on methods for the detection of adeno-associated viral DNA. We add a short overview of fluorescent microscope techniques and their advantages and challenges in detecting AAV.
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Affiliation(s)
- Susanne K Golm
- Cellular and Molecular Biotechnology, Faculty of Technology, Bielefeld University, 33615 Bielefeld, Germany
| | - Wolfgang Hübner
- Biomolecular Photonics, Faculty of Physics, Bielefeld University, 33615 Bielefeld, Germany
| | - Kristian M Müller
- Cellular and Molecular Biotechnology, Faculty of Technology, Bielefeld University, 33615 Bielefeld, Germany
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7
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Tumor antigen-loaded AAV vaccine drives protective immunity in a melanoma animal model. Mol Ther Methods Clin Dev 2023; 28:301-311. [PMID: 36851984 PMCID: PMC9957711 DOI: 10.1016/j.omtm.2023.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 01/29/2023] [Indexed: 02/04/2023]
Abstract
We previously described therapeutic opportunities provided by capsid- and expression cassette-optimized adeno-associated virus serotype 6 (AAV6) vectors to suppress tumor growth in both solid and metastatic mouse models by using artificial ovalbumin (OVA) immunogen. In the current study, we further elucidated the mechanism of function of a novel AAV-based vaccine loaded with the melanoma tumor-associated antigens premelanosome protein gp100, tyrosinase (Tyr), tyrosinase-related protein 1 (TRP1), and dopachrome tautomerase (TRP2). We showed that the AAV6-based vaccine creates cellular and humoral antigen-specific responses, while antigen expression at the site of vaccine injection was temporal, and the clearance of antigen coincided with T cell infiltration. Our data revealed the superior protective immune response of optimized AAV6-TRP1 compared with other self-antigens in a disease-free mouse model. We further assessed the ability of AAV6-TRP1 to protect animals from metastatic spread in the lungs and to extend animal survival by inhibiting solid tumor growth. Flow cytometry-based analysis indicated significant infiltration of CD8+ T cells and natural killer (NK) cells in the tumor site, as well as changes in the polarization of intratumoral macrophages. Altogether, our data strongly support the use of optimized AAV vectors for cancer vaccine development.
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8
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Critchley BJ, Gaspar HB, Benedetti S. Targeting the central nervous system in lysosomal storage diseases: Strategies to deliver therapeutics across the blood-brain barrier. Mol Ther 2023; 31:657-675. [PMID: 36457248 PMCID: PMC10014236 DOI: 10.1016/j.ymthe.2022.11.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 11/18/2022] [Accepted: 11/28/2022] [Indexed: 12/02/2022] Open
Abstract
Lysosomal storage diseases (LSDs) are multisystem inherited metabolic disorders caused by dysfunctional lysosomal activity, resulting in the accumulation of undegraded macromolecules in a variety of organs/tissues, including the central nervous system (CNS). Treatments include enzyme replacement therapy, stem/progenitor cell transplantation, and in vivo gene therapy. However, these treatments are not fully effective in treating the CNS as neither enzymes, stem cells, nor viral vectors efficiently cross the blood-brain barrier. Here, we review the latest advancements in improving delivery of different therapeutic agents to the CNS and comment upon outstanding questions in the field of neurological LSDs.
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Affiliation(s)
- Bethan J Critchley
- Infection, Immunity and Inflammation Research & Teaching Department, UCL Great Ormond Street Institute of Child Health, Zayed Centre for Research, London WC1N 1DZ, UK
| | - H Bobby Gaspar
- Infection, Immunity and Inflammation Research & Teaching Department, UCL Great Ormond Street Institute of Child Health, Zayed Centre for Research, London WC1N 1DZ, UK; Orchard Therapeutics Ltd., London EC4N 6EU, UK
| | - Sara Benedetti
- Infection, Immunity and Inflammation Research & Teaching Department, UCL Great Ormond Street Institute of Child Health, Zayed Centre for Research, London WC1N 1DZ, UK; NIHR Great Ormond Street Hospital Biomedical Research Centre, London, UK.
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9
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Meumann N, Cabanes-Creus M, Ertelt M, Navarro RG, Lucifora J, Yuan Q, Nien-Huber K, Abdelrahman A, Vu XK, Zhang L, Franke AC, Schmithals C, Piiper A, Vogt A, Gonzalez-Carmona M, Frueh JT, Ullrich E, Meuleman P, Talbot SR, Odenthal M, Ott M, Seifried E, Schoeder CT, Schwäble J, Lisowski L, Büning H. Adeno-associated virus serotype 2 capsid variants for improved liver-directed gene therapy. Hepatology 2023; 77:802-815. [PMID: 35976053 PMCID: PMC9936986 DOI: 10.1002/hep.32733] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 07/29/2022] [Accepted: 08/07/2022] [Indexed: 12/08/2022]
Abstract
BACKGROUND AND AIMS Current liver-directed gene therapies look for adeno-associated virus (AAV) vectors with improved efficacy. With this background, capsid engineering is explored. Whereas shuffled capsid library screenings have resulted in potent liver targeting variants with one first vector in human clinical trials, modifying natural serotypes by peptide insertion has so far been less successful. Here, we now report on two capsid variants, MLIV.K and MLIV.A, both derived from a high-throughput in vivo AAV peptide display selection screen in mice. APPROACH AND RESULTS The variants transduce primary murine and human hepatocytes at comparable efficiencies, a valuable feature in clinical development, and show significantly improved liver transduction efficacy, thereby allowing a dose reduction, and outperform parental AAV2 and AAV8 in targeting human hepatocytes in humanized mice. The natural heparan sulfate proteoglycan binding ability is markedly reduced, a feature that correlates with improved hepatocyte transduction. A further property that might contribute to the improved transduction efficacy is the lower capsid melting temperature. Peptide insertion also caused a moderate change in sensitivity to human sera containing anti-AAV2 neutralizing antibodies, revealing the impact of epitopes located at the basis of the AAV capsid protrusions. CONCLUSIONS In conclusion, MLIV.K and MLIV.A are AAV peptide display variants selected in immunocompetent mice with improved hepatocyte tropism and transduction efficiency. Because these features are maintained across species, MLIV variants provide remarkable potential for translation of therapeutic approaches from mice to men.
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Affiliation(s)
- Nadja Meumann
- Institute of Experimental Hematology , Hannover Medical School , Hannover , Germany.,Center for Molecular Medicine Cologne , University of Cologne , Cologne , Germany
| | - Marti Cabanes-Creus
- Translational Vectorology Research Unit , Children's Medical Research Institute , The University of Sydney , Sydney , New South Wales , Australia
| | - Moritz Ertelt
- Institute for Drug Discovery , University Leipzig Medical School , Leipzig , Germany.,Center for Scalable Data Analytics and Artificial Intelligence ScaDS.AI , Dresden/Leipzig , Germany
| | - Renina Gale Navarro
- Translational Vectorology Research Unit , Children's Medical Research Institute , The University of Sydney , Sydney , New South Wales , Australia
| | - Julie Lucifora
- Cancer Research Center of Lyon , Institut National de la Santé et la Recherche Médicale , Lyon , France
| | - Qinggong Yuan
- Department of Gastroenterology, Hepatology, and Endocrinology , Hannover Medical School , Hannover , Germany.,Twincore Centre for Experimental and Clinical Infection Research , Hannover , Germany
| | - Karin Nien-Huber
- Institute for Transfusion Medicine and Immunohematology , Goethe University Hospital Medical School , German Red Cross Blood Donor Service , Frankfurt , Germany
| | - Ahmed Abdelrahman
- Institute for Transfusion Medicine and Immunohematology , Goethe University Hospital Medical School , German Red Cross Blood Donor Service , Frankfurt , Germany
| | - Xuan-Khang Vu
- Institute of Experimental Hematology , Hannover Medical School , Hannover , Germany
| | - Liang Zhang
- Center for Molecular Medicine Cologne , University of Cologne , Cologne , Germany.,Institute of Pathology , University Hospital Cologne , Cologne , Germany
| | - Ann-Christin Franke
- Institute of Experimental Hematology , Hannover Medical School , Hannover , Germany
| | - Christian Schmithals
- Department of Internal Medicine I , University Hospital Frankfurt , Frankfurt , Germany
| | - Albrecht Piiper
- Department of Internal Medicine I , University Hospital Frankfurt , Frankfurt , Germany
| | - Annabelle Vogt
- Department of Internal Medicine I , University Hospital Bonn , Bonn , Germany
| | | | - Jochen T Frueh
- Experimental Immunology , Children's University Hospital , Goethe University Frankfurt , Frankfurt am Main , Germany
| | - Evelyn Ullrich
- Experimental Immunology , Children's University Hospital , Goethe University Frankfurt , Frankfurt am Main , Germany
| | - Philip Meuleman
- Laboratory of Liver Infectious Diseases , Faculty of Medicine and Health Sciences , Ghent University , Ghent , Belgium
| | - Steven R Talbot
- Institute for Laboratory Animal Science , Hannover Medical School , Hannover , Germany
| | - Margarete Odenthal
- Center for Molecular Medicine Cologne , University of Cologne , Cologne , Germany.,Institute of Pathology , University Hospital Cologne , Cologne , Germany
| | - Michael Ott
- Department of Gastroenterology, Hepatology, and Endocrinology , Hannover Medical School , Hannover , Germany.,Twincore Centre for Experimental and Clinical Infection Research , Hannover , Germany
| | - Erhard Seifried
- Institute for Transfusion Medicine and Immunohematology , Goethe University Hospital Medical School , German Red Cross Blood Donor Service , Frankfurt , Germany
| | - Clara T Schoeder
- Institute for Drug Discovery , University Leipzig Medical School , Leipzig , Germany
| | - Joachim Schwäble
- Institute for Transfusion Medicine and Immunohematology , Goethe University Hospital Medical School , German Red Cross Blood Donor Service , Frankfurt , Germany
| | - Leszek Lisowski
- Translational Vectorology Research Unit , Children's Medical Research Institute , The University of Sydney , Sydney , New South Wales , Australia.,Military Institute of Medicine , Laboratory of Molecular Oncology and Innovative Therapies , Warsaw , Poland
| | - Hildegard Büning
- Institute of Experimental Hematology , Hannover Medical School , Hannover , Germany.,Center for Molecular Medicine Cologne , University of Cologne , Cologne , Germany
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10
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Rode L, Bär C, Groß S, Rossi A, Meumann N, Viereck J, Abbas N, Xiao K, Riedel I, Gietz A, Zimmer K, Odenthal M, Büning H, Thum T. AAV capsid engineering identified two novel variants with improved in vivo tropism for cardiomyocytes. Mol Ther 2022; 30:3601-3618. [PMID: 35810332 PMCID: PMC9734024 DOI: 10.1016/j.ymthe.2022.07.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 07/06/2022] [Accepted: 07/06/2022] [Indexed: 01/01/2023] Open
Abstract
AAV vectors are promising delivery tools for human gene therapy. However, broad tissue tropism and pre-existing immunity against natural serotypes limit their clinical use. We identified two AAV capsid variants, AAV2-THGTPAD and AAV2-NLPGSGD, by in vivo AAV2 peptide display library screening in a murine model of pressure overload-induced cardiac hypertrophy. Both variants showed significantly improved efficacy in in vivo cardiomyocyte transduction compared with the parental serotype AAV2 as indicated by a higher number of AAV vector episomes in the nucleus and significant improved transduction efficiency. Both variants also outcompeted the reference serotype AAV9 regarding cardiomyocyte tropism, reaching comparable cardiac transduction efficiencies accompanied with liver de-targeting and decreased transduction efficiency of non-cardiac cells. Capsid modification influenced immunogenicity as sera of mice treated with AAV2-THGTPAD and AAV2-NLPGSGD demonstrated a poor neutralization capacity for the parental serotype and the novel variants. In a therapeutic setting, using the long non-coding RNA H19 in low vector dose conditions, novel AAV variants mediated superior anti-hypertrophic effects and revealed a further improved target-to-noise ratio, i.e., cardiomyocyte tropism. In conclusion, AAV2-THGTPAD and AAV2-NLPGSGD are promising novel tools for cardiac-directed gene therapy outperforming AAV9 regarding the specificity and therapeutic efficiency of in vivo cardiomyocyte transduction.
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Affiliation(s)
- Laura Rode
- Institute of Molecular and Translational Therapeutic Strategies (IMTTS), Hannover Medical School, OE 8886, Carl-Neuberg-Str. 1, 30635 Hannover, Germany
| | - Christian Bär
- Institute of Molecular and Translational Therapeutic Strategies (IMTTS), Hannover Medical School, OE 8886, Carl-Neuberg-Str. 1, 30635 Hannover, Germany; REBIRTH Center for Translational Regenerative Medicine, Hannover Medical School, 30625 Hannover, Germany; Fraunhofer Institute for Toxicology and Experimental Medicine, 30625 Hannover, Germany
| | - Sonja Groß
- Institute of Molecular and Translational Therapeutic Strategies (IMTTS), Hannover Medical School, OE 8886, Carl-Neuberg-Str. 1, 30635 Hannover, Germany
| | - Axel Rossi
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
| | - Nadja Meumann
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
| | - Janika Viereck
- Institute of Molecular and Translational Therapeutic Strategies (IMTTS), Hannover Medical School, OE 8886, Carl-Neuberg-Str. 1, 30635 Hannover, Germany
| | - Naisam Abbas
- Institute of Molecular and Translational Therapeutic Strategies (IMTTS), Hannover Medical School, OE 8886, Carl-Neuberg-Str. 1, 30635 Hannover, Germany
| | - Ke Xiao
- Institute of Molecular and Translational Therapeutic Strategies (IMTTS), Hannover Medical School, OE 8886, Carl-Neuberg-Str. 1, 30635 Hannover, Germany
| | - Isabelle Riedel
- Institute of Molecular and Translational Therapeutic Strategies (IMTTS), Hannover Medical School, OE 8886, Carl-Neuberg-Str. 1, 30635 Hannover, Germany
| | - Anika Gietz
- Institute of Molecular and Translational Therapeutic Strategies (IMTTS), Hannover Medical School, OE 8886, Carl-Neuberg-Str. 1, 30635 Hannover, Germany
| | - Karina Zimmer
- Institute of Molecular and Translational Therapeutic Strategies (IMTTS), Hannover Medical School, OE 8886, Carl-Neuberg-Str. 1, 30635 Hannover, Germany
| | - Margarete Odenthal
- Institute of Pathology, University Hospital of Cologne and Center for Molecular Medicine Cologne, University of Cologne, 50937 Cologne, Germany
| | - Hildegard Büning
- REBIRTH Center for Translational Regenerative Medicine, Hannover Medical School, 30625 Hannover, Germany; Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany.
| | - Thomas Thum
- Institute of Molecular and Translational Therapeutic Strategies (IMTTS), Hannover Medical School, OE 8886, Carl-Neuberg-Str. 1, 30635 Hannover, Germany; REBIRTH Center for Translational Regenerative Medicine, Hannover Medical School, 30625 Hannover, Germany; Fraunhofer Institute for Toxicology and Experimental Medicine, 30625 Hannover, Germany.
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11
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New vector and vaccine platforms: mRNA, DNA, viral vectors. Curr Opin HIV AIDS 2022; 17:338-344. [DOI: 10.1097/coh.0000000000000763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Sant’Anna TB, Araujo NM. Adeno-associated virus infection and its impact in human health: an overview. Virol J 2022; 19:173. [PMID: 36316711 PMCID: PMC9623951 DOI: 10.1186/s12985-022-01900-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 10/04/2022] [Accepted: 10/10/2022] [Indexed: 01/24/2023] Open
Abstract
Discovered as a contaminant of adenovirus stocks in the 1960s, adeno-associated virus (AAV) is a mono-stranded DNA virus that depends on helper factors to replicate. Even though AAV is endemic in the human population (35-80%), it is remarkable that many issues concerning the natural infection by this virus remain unanswered. In this study, we reflect on the main basic aspects of AAV biology and provide an overview of the studies exploring the impact of AAV infection on human health, focusing on three major research areas including, (i) cervical and (ii) liver cancer, and (iii) reproductive system disorders. Conflicting results have been obtained into the association of AAV infection with the occurrence of adverse reproductive outcomes, such as placental complications, spontaneous abortion, and fertility disorders, or with a protective role in HPV-related cervical carcinogenesis. Noteworthy, recent reports have identified AAV insertional mutagenesis as a novel risk factor for the development of hepatocellular carcinoma. This latest finding raises concern regarding the widespread usage of AAV vectors in liver-targeted gene therapy.
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Affiliation(s)
- Thaís B Sant’Anna
- grid.418068.30000 0001 0723 0931Laboratory of Molecular Virology, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil
| | - Natalia M Araujo
- grid.418068.30000 0001 0723 0931Laboratory of Molecular Virology, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil
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13
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Jäschke N, Büning H. Adeno-Associated Virus Vector Design-Moving the Adeno-Associated Virus to a Bioengineered Therapeutic Nanoparticle. Hematol Oncol Clin North Am 2022; 36:667-685. [PMID: 35778330 DOI: 10.1016/j.hoc.2022.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Although the number of market-approved gene therapies is still low, this new class of therapeutics has become an integral part of modern medicine. The success and safety of gene therapy depend on the vectors used to deliver the therapeutic material. Adeno-associated virus (AAV) vectors have emerged as the most frequently used delivery system for in vivo gene therapy. This success was achieved with first-generation vectors, using capsids derived from natural AAV serotypes. Their broad tropism, the high seroprevalence for many of the AAV serotypes in the human population, and the high vector doses needed to transduce a sufficient number of therapy-relevant target cells are challenges that are addressed by engineering the capsid and the vector genome, improving the efficacy of these biological nanoparticles.
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Affiliation(s)
- Nico Jäschke
- Institute of Experimental Hematology, Hannover Medical School, Carl-Neuberg-Str.1, Hannover 30625, Germany
| | - Hildegard Büning
- Institute of Experimental Hematology, Hannover Medical School, Carl-Neuberg-Str.1, Hannover 30625, Germany; REBIRTH Research Center for Translational Regenerative Medicine, Hannover Medical School, Carl-Neuberg-Str.1, Hannover 30625, Germany; German Center for Infection Research, Partner Site Hannover-Braunschweig.
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14
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Becker J, Fakhiri J, Grimm D. Fantastic AAV Gene Therapy Vectors and How to Find Them—Random Diversification, Rational Design and Machine Learning. Pathogens 2022; 11:pathogens11070756. [PMID: 35890005 PMCID: PMC9318892 DOI: 10.3390/pathogens11070756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 06/30/2022] [Accepted: 07/01/2022] [Indexed: 11/16/2022] Open
Abstract
Parvoviruses are a diverse family of small, non-enveloped DNA viruses that infect a wide variety of species, tissues and cell types. For over half a century, their intriguing biology and pathophysiology has fueled intensive research aimed at dissecting the underlying viral and cellular mechanisms. Concurrently, their broad host specificity (tropism) has motivated efforts to develop parvoviruses as gene delivery vectors for human cancer or gene therapy applications. While the sum of preclinical and clinical data consistently demonstrates the great potential of these vectors, these findings also illustrate the importance of enhancing and restricting in vivo transgene expression in desired cell types. To this end, major progress has been made especially with vectors based on Adeno-associated virus (AAV), whose capsid is highly amenable to bioengineering, repurposing and expansion of its natural tropism. Here, we provide an overview of the state-of-the-art approaches to create new AAV variants with higher specificity and efficiency of gene transfer in on-target cells. We first review traditional and novel directed evolution approaches, including high-throughput screening of AAV capsid libraries. Next, we discuss programmable receptor-mediated targeting with a focus on two recent technologies that utilize high-affinity binders. Finally, we highlight one of the latest stratagems for rational AAV vector characterization and optimization, namely, machine learning, which promises to facilitate and accelerate the identification of next-generation, safe and precise gene delivery vehicles.
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Affiliation(s)
- Jonas Becker
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, Center for Integrative Infectious Diseases Research (CIID), BioQuant, 69120 Heidelberg, Germany;
- Faculty of Biosciences, University of Heidelberg, 69120 Heidelberg, Germany
| | - Julia Fakhiri
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Munich, Roche Diagnostics GmbH, Nonnenwald 2, 82377 Penzberg, Germany
- Correspondence: (J.F.); (D.G.); Tel.: +49-174-3486203 (J.F.); +49-6221-5451331 (D.G.)
| | - Dirk Grimm
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, Center for Integrative Infectious Diseases Research (CIID), BioQuant, 69120 Heidelberg, Germany;
- German Center for Infection Research (DZIF), Partner Site Heidelberg, 69120 Heidelberg, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Heidelberg, 69120 Heidelberg, Germany
- Correspondence: (J.F.); (D.G.); Tel.: +49-174-3486203 (J.F.); +49-6221-5451331 (D.G.)
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15
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bin Umair M, Akusa FN, Kashif H, Seerat-e-Fatima, Butt F, Azhar M, Munir I, Ahmed M, Khalil W, Sharyar H, Rafique S, Shahid M, Afzal S. Viruses as tools in gene therapy, vaccine development, and cancer treatment. Arch Virol 2022; 167:1387-1404. [PMID: 35462594 PMCID: PMC9035288 DOI: 10.1007/s00705-022-05432-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 01/28/2022] [Indexed: 12/11/2022]
Abstract
Using viruses to our advantage has been a huge leap for humanity. Their ability to mediate horizontal gene transfer has made them useful tools for gene therapy, vaccine development, and cancer treatment. Adenoviruses, adeno-associated viruses, retroviruses, lentiviruses, alphaviruses, and herpesviruses are a few of the most common candidates for use as therapeutic agents or efficient gene delivery systems. Efforts are being made to improve and perfect viral-vector-based therapies to overcome potential or reported drawbacks. Some preclinical trials of viral vector vaccines have yielded positive results, indicating their potential as prophylactic or therapeutic vaccine candidates. Utilization of the oncolytic activity of viruses is the future of cancer therapy, as patients will then be free from the harmful effects of chemo- or radiotherapy. This review discusses in vitro and in vivo studies showing the brilliant therapeutic potential of viruses.
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Affiliation(s)
- Musab bin Umair
- Centre of Excellence in Molecular Biology (CEMB), University of the Punjab, 87-West Canal Bank Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Fujimura Nao Akusa
- Centre of Excellence in Molecular Biology (CEMB), University of the Punjab, 87-West Canal Bank Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Hadia Kashif
- Centre of Excellence in Molecular Biology (CEMB), University of the Punjab, 87-West Canal Bank Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Seerat-e-Fatima
- Centre of Excellence in Molecular Biology (CEMB), University of the Punjab, 87-West Canal Bank Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Fatima Butt
- Centre of Excellence in Molecular Biology (CEMB), University of the Punjab, 87-West Canal Bank Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Marium Azhar
- Centre of Excellence in Molecular Biology (CEMB), University of the Punjab, 87-West Canal Bank Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Iqra Munir
- Centre of Excellence in Molecular Biology (CEMB), University of the Punjab, 87-West Canal Bank Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Muhammad Ahmed
- Centre of Excellence in Molecular Biology (CEMB), University of the Punjab, 87-West Canal Bank Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Wajeeha Khalil
- Centre of Excellence in Molecular Biology (CEMB), University of the Punjab, 87-West Canal Bank Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Hafiz Sharyar
- Centre of Excellence in Molecular Biology (CEMB), University of the Punjab, 87-West Canal Bank Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Shazia Rafique
- Centre of Excellence in Molecular Biology (CEMB), University of the Punjab, 87-West Canal Bank Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Muhammad Shahid
- Centre of Excellence in Molecular Biology (CEMB), University of the Punjab, 87-West Canal Bank Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Samia Afzal
- Centre of Excellence in Molecular Biology (CEMB), University of the Punjab, 87-West Canal Bank Road, Thokar Niaz Baig, Lahore, Pakistan
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16
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Bucher K, Rodriguez-Bocanegra E, Fischer MD. Benefits and Shortcomings of Laboratory Model Systems in the Development of Genetic Therapies. Klin Monbl Augenheilkd 2022; 239:263-269. [PMID: 35316853 DOI: 10.1055/a-1757-9879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Gene therapeutic approaches promise treatment or even a cure of diseases that were previously untreatable. Retinal gene therapies tested in clinical trials comprise a wide range of different strategies, including gene supplementation therapies, in vivo gene editing, modulation of splicing mechanisms, or the suppression of gene expression. To guarantee efficient transfer of genetic material into the respective target cells while avoiding major adverse effects, the development of genetic therapies requires appropriate in vitro model systems that allow tests of efficacy and safety of the gene therapeutic approach. In this review, we introduce various in vitro models of different levels of complexity used in the development of genetic therapies and discuss their respective benefits and shortcomings using the example of adeno-associated virus-based retinal gene therapy.
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Affiliation(s)
- Kirsten Bucher
- University Eye Hospital, University Hospital Tübingen Clinic of Ophthalmology, Tubingen, Germany.,Institute for Ophthalmic Research, University Hospital Tübingen Clinic of Ophthalmology, Tubingen, Germany
| | | | - M Dominik Fischer
- University Eye Hospital, University Hospital Tübingen Clinic of Ophthalmology, Tubingen, Germany.,Institute for Ophthalmic Research, University Hospital Tübingen Clinic of Ophthalmology, Tubingen, Germany.,Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom of Great Britain and Northern Ireland.,Department of Clinical Neurosciences, University of Oxford Nuffield Laboratory of Ophthalmology, Oxford, United Kingdom of Great Britain and Northern Ireland
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17
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Westhaus A, Cabanes Creus M, Jonker T, Sallard E, Navarro RG, Zhu E, Baltazar G, Lee S, Wilmott P, Gonzalez-Cordero A, Santilli G, Thrasher AJ, Alexander IE, Lisowski L. AAV-p40 bioengineering platform for variant selection based on transgene expression. Hum Gene Ther 2022; 33:664-682. [PMID: 35297686 PMCID: PMC10112876 DOI: 10.1089/hum.2021.278] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The power of AAV directed evolution for identifying novel vector variants with improved properties is well established, as evidenced by numerous publications reporting novel AAV variants. However, most capsid variants reported to date have been identified using either replication-competent selection platforms or PCR-based capsid DNA recovery methods, which can bias the selection towards efficient replication or unproductive intracellular trafficking, respectively. A central objective of this study was to validate a functional transduction (FT)-based method for rapid identification of novel AAV variants based on AAV capsid mRNA expression in target cells. We performed a comparison of the FT platform to existing replication competent strategies. Based on the selection kinetics and function of novel capsids identified in an in vivo screen in a xenograft model of human hepatocytes, we identified the mRNA-based FT selection as the most optimal AAV selection method. Lastly, to gain insight into the mRNA-based selection mechanism driven by the native AAV-p40 promoter, we studied its activity in a range of in vitro and in vivo targets. We found AAV-p40 to be a ubiquitously active promoter that can be modified for cell type-specific expression by incorporating binding sites for silencing transcription factors, allowing for cell-type-specific library selection.
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Affiliation(s)
- Adrian Westhaus
- Children's Medical Research Institute, 58454, Translational Vectorology Group, 214 Hawkesbury Road, Westmead, New South Wales, Australia, 2145;
| | - Marti Cabanes Creus
- Children's Medical Research Institute, 58454, Translational Vectorology Group, Westmead, New South Wales, Australia;
| | - Timo Jonker
- Children's Medical Research Institute, 58454, Westmead, New South Wales, Australia;
| | - Erwan Sallard
- Children's Medical Research Institute, 58454, Westmead, New South Wales, Australia;
| | - Renina Gale Navarro
- Children's Medical Research Institute, 58454, Translational Vectorology Group, 214 Hawkesbury Road, Westmead, New South Wales, Australia, 2145;
| | - Erhua Zhu
- Children's Medical Research Institute, 58454, Gene Therapy Research Unit, Westmead, New South Wales, Australia;
| | - Grober Baltazar
- Children's Medical Research Institute, 58454, Translational Vectorology Group, Westmead, New South Wales, Australia;
| | - Scott Lee
- Children's Medical Research Institute, 58454, Westmead, New South Wales, Australia;
| | - Patrick Wilmott
- Children's Medical Research Institute, 58454, Translational Vectorology Group, 214 Hawkesbury Rd, Westmead, New South Wales, Australia, 2145;
| | - Anai Gonzalez-Cordero
- The University of Sydney Faculty of Medicine and Health, 522555, Stem Cell & Organoid Facility and Stem Cell Medicine Group, Children's Medical Research Institute, 214 Hawkesbury Road, Westmead, Sydney, New South Wales, Australia, 2145;
| | - Giorgia Santilli
- UCL-Institute of Child Health, Centre for Immunodeficiencies, 30 guilford street, London, United Kingdom of Great Britain and Northern Ireland, WC1N 1EH;
| | - Adrian J Thrasher
- Institute of Child Health, London, UK, Molecular Immunology Unit, 30 guilford street, london, United Kingdom of Great Britain and Northern Ireland, wc1n1eh;
| | - Ian Edward Alexander
- Sydney Children's Hospitals Network and Children's Medical Research Institute, Corner Hawkesbury Rd & Hainsworth St, Locked Bag 4001, Westmead, New South Wales, Australia, 2145 Sydney;
| | - Leszek Lisowski
- Children's Medical Research Institute, 58454, Translational Vectorology Research Unit, Westmead, New South Wales, Australia;
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18
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Aliahmad P, Miyake-Stoner SJ, Geall AJ, Wang NS. Next generation self-replicating RNA vectors for vaccines and immunotherapies. Cancer Gene Ther 2022:10.1038/s41417-022-00435-8. [PMID: 35194198 PMCID: PMC8861484 DOI: 10.1038/s41417-022-00435-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 01/18/2022] [Accepted: 01/28/2022] [Indexed: 01/06/2023]
Abstract
RNA technology has recently come to the forefront of innovative medicines and is being explored for a wide range of therapies, including prophylactic and therapeutic vaccines, biotherapeutic protein expression and gene therapy. In addition to conventional mRNA platforms now approved for prophylactic SARS-CoV2 vaccines, synthetic self-replicating RNA vaccines are currently being evaluated in the clinic for infectious disease and oncology. The prototypical srRNA vectors in clinical development are derived from alphaviruses, specifically Venezuelan Equine Encephalitis Virus (VEEV). While non-VEEV alphaviral strains have been explored as single cycle viral particles, their use as synthetic vectors largely remains under-utilized in clinical applications. Here we describe the potential commonalities and differences in synthetic alphaviral srRNA vectors in host cell interactions, immunogenicity, cellular delivery, and cargo expression. Thus, unlike the current thinking that VEEV-based srRNA is a one-size-fits-all platform, we argue that a new drug development approach leveraging panels of customizable, synthetic srRNA vectors will be required for clinical success.
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19
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Meumann N, Schmithals C, Elenschneider L, Hansen T, Balakrishnan A, Hu Q, Hook S, Schmitz J, Bräsen JH, Franke AC, Olarewaju O, Brandenberger C, Talbot SR, Fangmann J, Hacker UT, Odenthal M, Ott M, Piiper A, Büning H. Hepatocellular Carcinoma Is a Natural Target for Adeno-Associated Virus (AAV) 2 Vectors. Cancers (Basel) 2022; 14:cancers14020427. [PMID: 35053588 PMCID: PMC8774135 DOI: 10.3390/cancers14020427] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 12/21/2021] [Accepted: 01/11/2022] [Indexed: 02/04/2023] Open
Abstract
Simple Summary Gene therapy is a novel approach to treat diseases by introducing corrective genetic information into target cells. Adeno-associated virus vectors are the most frequently applied gene delivery tools for in vivo gene therapy and are also studied as part of innovative anticancer strategies. Here, we report on the natural preference of AAV2 vectors for hepatocellular carcinoma (HCC) compared to nonmalignant liver cells in mice and human tissue. This preference in transduction is due to the improved intracellular processing of AAV2 vectors in HCC, resulting in significantly more vector genomes serving as templates for transcription in the cell nucleus. Based on this natural tropism for HCC, novel therapeutic strategies can be designed or existing therapeutic approaches can be strengthened as they currently result in only a minor improvement of the poor prognosis for most liver cancer patients. Abstract Although therapeutic options are gradually improving, the overall prognosis for patients with hepatocellular carcinoma (HCC) is still poor. Gene therapy-based strategies are developed to complement the therapeutic armamentarium, both in early and late-stage disease. For efficient delivery of transgenes with antitumor activity, vectors demonstrating preferred tumor tropism are required. Here, we report on the natural tropism of adeno-associated virus (AAV) serotype 2 vectors for HCC. When applied intravenously in transgenic HCC mouse models, similar amounts of vectors were detected in the liver and liver tumor tissue. In contrast, transduction efficiency, as indicated by the level of transgene product, was moderate in the liver but was elevated up to 19-fold in mouse tumor tissue. Preferred transduction of HCC compared to hepatocytes was confirmed in precision-cut liver slices from human patient samples. Our mechanistic studies revealed that this preference is due to the improved intracellular processing of AAV2 vectors in HCC, resulting, for example, in nearly 4-fold more AAV vector episomes that serve as templates for gene transcription. Given this background, AAV2 vectors ought to be considered to strengthen current—or develop novel—strategies for treating HCC.
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Affiliation(s)
- Nadja Meumann
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany; (N.M.); (A.-C.F.); (O.O.); (U.T.H.)
- REBIRTH Research Center for Translational Regenerative Medicine, Hannover Medical School, 30625 Hannover, Germany
- Center for Molecular Medicine Cologne, University of Cologne, 50931 Cologne, Germany;
| | - Christian Schmithals
- Department of Medicine 1, University Hospital, Goethe University Frankfurt, 60590 Frankfurt, Germany; (C.S.); (A.P.)
| | - Leroy Elenschneider
- Fraunhofer Institute for Toxicology and Experimental Medicine Preclinical Pharmacology and In-Vitro Toxicology, 30625 Hannover, Germany; (L.E.); (T.H.)
| | - Tanja Hansen
- Fraunhofer Institute for Toxicology and Experimental Medicine Preclinical Pharmacology and In-Vitro Toxicology, 30625 Hannover, Germany; (L.E.); (T.H.)
| | - Asha Balakrishnan
- Clinic for Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, 30625 Hannover, Germany; (A.B.); (Q.H.); (S.H.); (M.O.)
- Twincore Centre for Experimental and Clinical Infection Research, 30625 Hannover, Germany
| | - Qingluan Hu
- Clinic for Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, 30625 Hannover, Germany; (A.B.); (Q.H.); (S.H.); (M.O.)
- Twincore Centre for Experimental and Clinical Infection Research, 30625 Hannover, Germany
| | - Sebastian Hook
- Clinic for Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, 30625 Hannover, Germany; (A.B.); (Q.H.); (S.H.); (M.O.)
- Twincore Centre for Experimental and Clinical Infection Research, 30625 Hannover, Germany
| | - Jessica Schmitz
- Nephropathology Unit, Institute of Pathology, Hannover Medical School, 30625 Hannover, Germany; (J.S.); (J.H.B.)
| | - Jan Hinrich Bräsen
- Nephropathology Unit, Institute of Pathology, Hannover Medical School, 30625 Hannover, Germany; (J.S.); (J.H.B.)
| | - Ann-Christin Franke
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany; (N.M.); (A.-C.F.); (O.O.); (U.T.H.)
| | - Olaniyi Olarewaju
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany; (N.M.); (A.-C.F.); (O.O.); (U.T.H.)
- REBIRTH Research Center for Translational Regenerative Medicine, Hannover Medical School, 30625 Hannover, Germany
| | - Christina Brandenberger
- Institute of Functional and Applied Anatomy, Hannover Medical School, 30625 Hannover, Germany;
- Biomedical Research in Endstage and Obstructive Lung Research (BREATH), German Center for Lung Research (DZL), 30625 Hannover, Germany
| | - Steven R. Talbot
- Institute for Laboratory Animal Science, Hannover Medical School, 30625 Hannover, Germany;
| | - Josef Fangmann
- KRH Klinikum Siloah, Liver Center Hannover (LCH), 30459 Hannover, Germany;
| | - Ulrich T. Hacker
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany; (N.M.); (A.-C.F.); (O.O.); (U.T.H.)
- Department of Oncology, Gastroenterology, Hepatology, Pulmonology, and Infectious Diseases, University Cancer Center Leipzig (UCCL), Leipzig University Medical Center, 04103 Leipzig, Germany
| | - Margarete Odenthal
- Center for Molecular Medicine Cologne, University of Cologne, 50931 Cologne, Germany;
- Institute of Pathology, University Hospital Cologne, 50931 Cologne, Germany
| | - Michael Ott
- Clinic for Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, 30625 Hannover, Germany; (A.B.); (Q.H.); (S.H.); (M.O.)
- Twincore Centre for Experimental and Clinical Infection Research, 30625 Hannover, Germany
| | - Albrecht Piiper
- Department of Medicine 1, University Hospital, Goethe University Frankfurt, 60590 Frankfurt, Germany; (C.S.); (A.P.)
- German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Hildegard Büning
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany; (N.M.); (A.-C.F.); (O.O.); (U.T.H.)
- REBIRTH Research Center for Translational Regenerative Medicine, Hannover Medical School, 30625 Hannover, Germany
- Center for Molecular Medicine Cologne, University of Cologne, 50931 Cologne, Germany;
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
- Correspondence: ; Tel.: +49-511-532-5106
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20
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Kok CY, MacLean LM, Ho JC, Lisowski L, Kizana E. Potential Applications for Targeted Gene Therapy to Protect Against Anthracycline Cardiotoxicity: JACC: CardioOncology Primer. JACC CardioOncol 2022; 3:650-662. [PMID: 34988473 PMCID: PMC8702812 DOI: 10.1016/j.jaccao.2021.09.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 08/30/2021] [Accepted: 09/08/2021] [Indexed: 12/26/2022] Open
Abstract
Anthracyclines are associated with risk of significant dose-dependent cardiotoxicity. Conventional heart failure therapies have neither ameliorated declining cardiac function nor addressed the underlying cause. Gene therapy may confer long-term cardioprotection by rendering the heart resistant to anthracyclines after 1 treatment, although the optimal therapeutic target remains to be elucidated. Recombinant adeno-associated virus is now clinically approved for the treatment of lipoprotein lipase deficiency, spinal muscular atrophy, and hereditary transthyretin amyloidosis. High-throughput methods allow selection of recombinant adeno-associated virus capsids that facilitate efficient gene delivery to specific target cells. Vector safety is enhanced by incorporating cardiac-specific promoters into vector design and localizing delivery to reduce off-target risk. Any cardioprotective transgene may bear a degree of risk as they may play as yet unknown roles, which require careful assessment using clinically relevant models. The innovative technologies outlined here make gene therapy a promising proof of principle, with potential further application to nonanthracycline chemotherapeutics. Protection against anthracycline cardiotoxicity may be achieved by gene delivery to the heart. The optimal cardioprotective target gene remains to be identified. Targeted gene expression in human myocytes can now be achieved with advances in AAV vectorology. It is critical to minimize risk of off-target effects which may impede anthracycline oncotherapy.
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Affiliation(s)
- Cindy Y Kok
- Centre for Heart Research, The Westmead Institute for Medical Research, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.,Westmead Clinical School, the Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Lauren M MacLean
- Centre for Heart Research, The Westmead Institute for Medical Research, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Jett C Ho
- Centre for Heart Research, The Westmead Institute for Medical Research, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Leszek Lisowski
- Military Institute of Medicine, Laboratory of Molecular Oncology and Innovative Therapies, Warsaw, Poland.,Translational Vectorology Research Unit, Children's Medical Research Institute, Faculty of Medicine and Health, The University of Sydney, Westmead, New South Wales, Australia.,Vector and Genome Engineering Facility, Children's Medical Research Institute, Faculty of Medicine and Health, The University of Sydney, Westmead, New South Wales, Australia
| | - Eddy Kizana
- Centre for Heart Research, The Westmead Institute for Medical Research, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.,Westmead Clinical School, the Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.,Department of Cardiology, Westmead Hospital, Sydney, New South Wales, Australia
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21
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Hamann MV, Beschorner N, Vu XK, Hauber I, Lange UC, Traenkle B, Kaiser PD, Foth D, Schneider C, Büning H, Rothbauer U, Hauber J. Improved targeting of human CD4+ T cells by nanobody-modified AAV2 gene therapy vectors. PLoS One 2021; 16:e0261269. [PMID: 34928979 PMCID: PMC8687595 DOI: 10.1371/journal.pone.0261269] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 11/26/2021] [Indexed: 12/12/2022] Open
Abstract
Adeno-associated viruses (AAV) are considered non-pathogenic in humans, and thus have been developed into powerful vector platforms for in vivo gene therapy. Although the various AAV serotypes display broad tropism, frequently infecting multiple tissues and cell types, vectors for specific and efficient targeting of human CD4+ T lymphocytes are largely missing. In fact, a substantial translational bottleneck exists in the field of therapeutic gene transfer that would require in vivo delivery into peripheral disease-related lymphocytes for subsequent genome editing. To solve this issue, capsid modification for retargeting AAV tropism, and in turn improving vector potency, is considered a promising strategy. Here, we genetically modified the minor AAV2 capsid proteins, VP1 and VP2, with a set of novel nanobodies with high-affinity for the human CD4 receptor. These novel vector variants demonstrated improved targeting of human CD4+ cells, including primary human peripheral blood mononuclear cells (PBMC) and purified human CD4+ T lymphocytes. Thus, the technical approach presented here provides a promising strategy for developing specific gene therapy vectors, particularly targeting disease-related peripheral blood CD4+ leukocytes.
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Affiliation(s)
- Martin V. Hamann
- Heinrich Pette Institute – Leibniz Institute for Experimental Virology (HPI), Hamburg, Germany
- German Center for Infection Research (DZIF), Partner Site Hamburg – Lübeck – Borstel – Riems, Hamburg, Germany
| | - Niklas Beschorner
- Heinrich Pette Institute – Leibniz Institute for Experimental Virology (HPI), Hamburg, Germany
- German Center for Infection Research (DZIF), Partner Site Hamburg – Lübeck – Borstel – Riems, Hamburg, Germany
| | - Xuan-Khang Vu
- Institute of Experimental Haematology, Hannover Medical School, Hannover, Germany
| | - Ilona Hauber
- Heinrich Pette Institute – Leibniz Institute for Experimental Virology (HPI), Hamburg, Germany
| | - Ulrike C. Lange
- Heinrich Pette Institute – Leibniz Institute for Experimental Virology (HPI), Hamburg, Germany
- German Center for Infection Research (DZIF), Partner Site Hamburg – Lübeck – Borstel – Riems, Hamburg, Germany
- Department of Anaesthesiology, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Bjoern Traenkle
- Natural and Medical Science Institute at the University Tübingen (NMI), Reutlingen, Germany
| | - Philipp D. Kaiser
- Natural and Medical Science Institute at the University Tübingen (NMI), Reutlingen, Germany
| | - Daniel Foth
- Heinrich Pette Institute – Leibniz Institute for Experimental Virology (HPI), Hamburg, Germany
| | - Carola Schneider
- Heinrich Pette Institute – Leibniz Institute for Experimental Virology (HPI), Hamburg, Germany
| | - Hildegard Büning
- German Center for Infection Research (DZIF), Partner Site Hamburg – Lübeck – Borstel – Riems, Hamburg, Germany
- Institute of Experimental Haematology, Hannover Medical School, Hannover, Germany
| | - Ulrich Rothbauer
- Natural and Medical Science Institute at the University Tübingen (NMI), Reutlingen, Germany
- Pharmaceutical Biotechnology, Eberhard Karls University Tübingen, Reutlingen, Germany
| | - Joachim Hauber
- Heinrich Pette Institute – Leibniz Institute for Experimental Virology (HPI), Hamburg, Germany
- German Center for Infection Research (DZIF), Partner Site Hamburg – Lübeck – Borstel – Riems, Hamburg, Germany
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22
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Kofoed RH, Heinen S, Silburt J, Dubey S, Dibia CL, Maes M, Simpson EM, Hynynen K, Aubert I. Transgene distribution and immune response after ultrasound delivery of rAAV9 and PHP.B to the brain in a mouse model of amyloidosis. Mol Ther Methods Clin Dev 2021; 23:390-405. [PMID: 34761053 PMCID: PMC8560718 DOI: 10.1016/j.omtm.2021.10.001] [Citation(s) in RCA: 9] [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: 04/01/2021] [Revised: 08/12/2021] [Accepted: 10/05/2021] [Indexed: 01/01/2023]
Abstract
Efficient disease-modifying treatments for Alzheimer disease, the most common form of dementia, have yet to be established. Gene therapy has the potential to provide the long-term production of therapeutic in the brain following a single administration. However, the blood-brain barrier poses a challenge for gene delivery to the adult brain. We investigated the transduction efficiency and immunological response following non-invasive gene-delivery strategies to the brain of a mouse model of amyloidosis. Two emerging technologies enabling gene delivery across the blood-brain barrier were used to establish the minimal vector dosage required to reach the brain: (1) focused ultrasound combined with intravenous microbubbles, which increases the permeability of the blood-brain barrier at targeted sites and (2) the recombinant adeno-associated virus (rAAV)-based capsid named rAAV-PHP.B. We found that equal intravenous dosages of rAAV9 combined with focused ultrasound, or rAAV-PHP.B, were required for brain gene delivery. In contrast to rAAV9, focused ultrasound did not decrease the rAAV-PHP.B dosage required to transduce brain cells in a mouse model of amyloidosis. The non-invasive rAAV delivery to the brain using rAAV-PHP.B or rAAV9 with focused ultrasound triggered an immune reaction including major histocompatibility complex class II expression, complement system and microglial activation, and T cell infiltration.
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Affiliation(s)
- Rikke Hahn Kofoed
- Biological Sciences, Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON M4N 3M5, Canada
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Stefan Heinen
- Biological Sciences, Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON M4N 3M5, Canada
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Joseph Silburt
- Biological Sciences, Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON M4N 3M5, Canada
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Sonam Dubey
- Biological Sciences, Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON M4N 3M5, Canada
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Chinaza Lilian Dibia
- Biological Sciences, Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON M4N 3M5, Canada
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Miriam Maes
- Biological Sciences, Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON M4N 3M5, Canada
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Elizabeth M. Simpson
- Centre for Molecular Medicine and Therapeutics at British Columbia Children’s Hospital, Department of Medical Genetics, The University of British Columbia, Vancouver, BC V5Z 4H4, Canada
| | - Kullervo Hynynen
- Physical Sciences, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON M4N 3M5, Canada
- Department of Medical Biophysics, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5G 1L7, Canada
| | - Isabelle Aubert
- Biological Sciences, Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON M4N 3M5, Canada
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
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23
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Ding Y, Li Z, Jaklenec A, Hu Q. Vaccine delivery systems toward lymph nodes. Adv Drug Deliv Rev 2021; 179:113914. [PMID: 34363861 PMCID: PMC9418125 DOI: 10.1016/j.addr.2021.113914] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 07/05/2021] [Accepted: 07/31/2021] [Indexed: 12/15/2022]
Abstract
Strategies of improving vaccine targeting ability toward lymph nodes have been attracting considerable interest in recent years, though there are remaining delivery barriers based on the inherent properties of lymphatic systems and limited administration routes of vaccination. Recently, emerging vaccine delivery systems using various materials as carriers are widely developed to achieve efficient lymph node targeting and improve vaccine-triggered adaptive immune response. In this review, to further optimize the vaccine targeting ability for future research, the design principles of lymph node targeting vaccine delivery based on the anatomy of lymph nodes and vaccine administration routes are first summarized. Then different designs of lymph node targeting vaccine delivery systems, including vaccine delivery systems in clinical applications, are carefully surveyed. Also, the challenges and opportunities of current delivery systems for vaccines are concluded in the end.
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Affiliation(s)
- Yingyue Ding
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, United States,Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, United States
| | - Zhaoting Li
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, United States,Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, United States
| | - Ana Jaklenec
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, United States
| | - Quanyin Hu
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, United States; Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, United States.
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24
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Riyad JM, Weber T. Intracellular trafficking of adeno-associated virus (AAV) vectors: challenges and future directions. Gene Ther 2021; 28:683-696. [PMID: 33658649 PMCID: PMC8413391 DOI: 10.1038/s41434-021-00243-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 01/27/2021] [Accepted: 02/05/2021] [Indexed: 02/07/2023]
Abstract
In the last two decades, recombinant adeno-associated virus has emerged as the most popular gene therapy vector. Recently AAV gene therapy has been approved by the FDA for the treatment of two rare genetic disorders, namely the early childhood blindness disease Leber congenital amaurosis and spinal muscular atrophy (SMA). As is the case for the treatment of SMA, if the AAV vector must be administered systemically, very high vector doses are often required for therapeutic efficacy. But higher vector doses inevitably increase the risk of adverse events. The tragic death of three children in a clinical trial to treat X-linked myotubular myopathy with an AAV vector has thrown this limitation into sharp relief. Regardless of the precise cause(s) that led to the death of the two children, it is critical that we develop better AAV vectors to achieve therapeutic levels of expression with lower vector doses. To transduce successfully a target cell, AAV has to overcome both systemic as well as cellular roadblocks. In this review, we discuss some of the most prominent cellular roadblocks that AAV must get past to deliver successfully its therapeutic payload. We also highlight recent advancements in our knowledge of AAV biology that can potentially be harnessed to improve AAV vector performance and thereby make AAV gene therapy safer.
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Affiliation(s)
- Jalish M Riyad
- Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Thomas Weber
- Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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25
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Varin J, Morival C, Maillard N, Adjali O, Cronin T. Risk Mitigation of Immunogenicity: A Key to Personalized Retinal Gene Therapy. Int J Mol Sci 2021; 22:12818. [PMID: 34884622 PMCID: PMC8658027 DOI: 10.3390/ijms222312818] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 11/17/2021] [Accepted: 11/23/2021] [Indexed: 12/27/2022] Open
Abstract
Gene therapy (GT) for ocular disorders has advanced the most among adeno-associated virus (AAV)-mediated therapies, with one product already approved in the market. The bank of retinal gene mutations carefully compiled over 30 years, the small retinal surface that does not require high clinical vector stocks, and the relatively immune-privileged environment of the eye explain such success. However, adverse effects due to AAV-delivery, though rare in the retina have led to the interruption of clinical trials. Risk mitigation, as the key to safe and efficient GT, has become the focus of 'bedside-back-to-bench' studies. Herein, we overview the inflammatory adverse events described in retinal GT trials and analyze which components of the retinal immunological environment might be the most involved in these immune responses, with a focus on the innate immune system composed of microglial surveillance. We consider the factors that can influence inflammation in the retina after GT such as viral sensors in the retinal tissue and CpG content in promoters or transgene sequences. Finally, we consider options to reduce the immunological risk, including dose, modified capsids or exclusion criteria for clinical trials. A better understanding and mitigation of immune risk factors inducing host immunity in AAV-mediated retinal GT is the key to achieving safe and efficient GT.
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Affiliation(s)
| | | | | | - Oumeya Adjali
- CHU de Nantes, INSERM UMR1089, Translational Gene Therapy for Genetic Diseases, Université de Nantes, F-44200 Nantes, France; (J.V.); (C.M.); (N.M.)
| | - Therese Cronin
- CHU de Nantes, INSERM UMR1089, Translational Gene Therapy for Genetic Diseases, Université de Nantes, F-44200 Nantes, France; (J.V.); (C.M.); (N.M.)
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26
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Rapti K, Grimm D. Adeno-Associated Viruses (AAV) and Host Immunity - A Race Between the Hare and the Hedgehog. Front Immunol 2021; 12:753467. [PMID: 34777364 PMCID: PMC8586419 DOI: 10.3389/fimmu.2021.753467] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 09/28/2021] [Indexed: 12/12/2022] Open
Abstract
Adeno-associated viruses (AAV) have emerged as the lead vector in clinical trials and form the basis for several approved gene therapies for human diseases, mainly owing to their ability to sustain robust and long-term in vivo transgene expression, their amenability to genetic engineering of cargo and capsid, as well as their moderate toxicity and immunogenicity. Still, recent reports of fatalities in a clinical trial for a neuromuscular disease, although linked to an exceptionally high vector dose, have raised new caution about the safety of recombinant AAVs. Moreover, concerns linger about the presence of pre-existing anti-AAV antibodies in the human population, which precludes a significant percentage of patients from receiving, and benefitting from, AAV gene therapies. These concerns are exacerbated by observations of cellular immune responses and other adverse events, including detrimental off-target transgene expression in dorsal root ganglia. Here, we provide an update on our knowledge of the immunological and molecular race between AAV (the “hedgehog”) and its human host (the “hare”), together with a compendium of state-of-the-art technologies which provide an advantage to AAV and which, thus, promise safer and more broadly applicable AAV gene therapies in the future.
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Affiliation(s)
- Kleopatra Rapti
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, Heidelberg, Germany.,BioQuant Center, BQ0030, University of Heidelberg, Heidelberg, Germany
| | - Dirk Grimm
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, Heidelberg, Germany.,BioQuant Center, BQ0030, University of Heidelberg, Heidelberg, Germany.,German Center for Infection Research Deutsches Zentrum für Infektionsforschung (DZIF) and German Center for Cardiovascular Research Deutsches Zentrum für Herz-Kreislauf-Erkrankungen (DZHK), Partner Site Heidelberg, Heidelberg, Germany
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27
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Brown D, Altermatt M, Dobreva T, Chen S, Wang A, Thomson M, Gradinaru V. Deep Parallel Characterization of AAV Tropism and AAV-Mediated Transcriptional Changes via Single-Cell RNA Sequencing. Front Immunol 2021; 12:730825. [PMID: 34759919 PMCID: PMC8574206 DOI: 10.3389/fimmu.2021.730825] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 09/17/2021] [Indexed: 12/21/2022] Open
Abstract
Engineered variants of recombinant adeno-associated viruses (rAAVs) are being developed rapidly to meet the need for gene-therapy delivery vehicles with particular cell-type and tissue tropisms. While high-throughput AAV engineering and selection methods have generated numerous variants, subsequent tropism and response characterization have remained low throughput and lack resolution across the many relevant cell and tissue types. To fully leverage the output of these large screening paradigms across multiple targets, we have developed an experimental and computational single-cell RNA sequencing (scRNA-seq) pipeline for in vivo characterization of barcoded rAAV pools at high resolution. Using this platform, we have both corroborated previously reported viral tropisms and discovered unidentified AAV capsid targeting biases. As expected, we observed that the tropism profile of AAV.CAP-B10 in mice was shifted toward neurons and away from astrocytes when compared with AAV-PHP.eB. Transcriptomic analysis revealed that this neuronal bias is due mainly to increased targeting efficiency for glutamatergic neurons, which we confirmed by RNA fluorescence in situ hybridization. We further uncovered cell subtype tropisms of AAV variants in vascular and glial cells, such as low transduction of pericytes and Myoc+ astrocytes. Additionally, we have observed cell-type-specific transitory responses to systemic AAV-PHP.eB administration, such as upregulation of genes involved in p53 signaling in endothelial cells three days post-injection, which return to control levels by day twenty-five. The presented experimental and computational approaches for parallel characterization of AAV tropism will facilitate the advancement of safe and precise gene delivery vehicles, and showcase the power of understanding responses to gene therapies at the single-cell level.
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Affiliation(s)
- David Brown
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Michael Altermatt
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Tatyana Dobreva
- Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Sisi Chen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Alexander Wang
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, United States
| | - Matt Thomson
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Viviana Gradinaru
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
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28
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Macdonald J, Marx J, Büning H. Capsid-Engineering for Central Nervous System-Directed Gene Therapy with Adeno-Associated Virus Vectors. Hum Gene Ther 2021; 32:1096-1119. [PMID: 34662226 DOI: 10.1089/hum.2021.169] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Closing the gap in knowledge on the cause of neurodegenerative disorders is paving the way toward innovative treatment strategies, among which gene therapy has emerged as a top candidate. Both conventional gene therapy and genome editing approaches are being developed, and a great number of human clinical trials are ongoing. Already 2 years ago, the first gene therapy for a neurodegenerative disease, spinal muscular atrophy type 1 (SMA1), obtained market approval. To realize such innovative strategies, gene therapy delivery tools are key assets. Here, we focus on recombinant adeno-associated virus (AAV) vectors and report on strategies to improve first-generation vectors. Current efforts focus on the viral capsid to modify the host-vector interaction aiming at increasing the efficacy of target cell transduction, at simplifying vector administration, and at reducing the risk of vector dose-related side effects.
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Affiliation(s)
- Josephine Macdonald
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,REBIRTH Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany
| | - Jennifer Marx
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,REBIRTH Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany
| | - Hildegard Büning
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,REBIRTH Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany
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29
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Griciuc A, Federico AN, Natasan J, Forte AM, McGinty D, Nguyen H, Volak A, LeRoy S, Gandhi S, Lerner EP, Hudry E, Tanzi RE, Maguire CA. Gene therapy for Alzheimer's disease targeting CD33 reduces amyloid beta accumulation and neuroinflammation. Hum Mol Genet 2021; 29:2920-2935. [PMID: 32803224 DOI: 10.1093/hmg/ddaa179] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/03/2020] [Accepted: 07/29/2020] [Indexed: 02/06/2023] Open
Abstract
Neuroinflammation is a key contributor to the pathology of Alzheimer's disease (AD). CD33 (Siglec-3) is a transmembrane sialic acid-binding receptor on the surface of microglial cells. CD33 is upregulated on microglial cells from post-mortem AD patient brains, and high levels of CD33 inhibit uptake and clearance of amyloid beta (Aβ) in microglial cell cultures. Furthermore, knockout of CD33 reduces amyloid plaque burden in mouse models of AD. Here, we tested whether a gene therapy strategy to reduce CD33 on microglia in AD could decrease Aβ plaque load. Intracerebroventricular injection of an adeno-associated virus (AAV) vector-based system encoding an artificial microRNA targeting CD33 (miRCD33) into APP/PS1 mice reduced CD33 mRNA and TBS-soluble Aβ40 and Aβ42 levels in brain extracts. Treatment of APP/PS1 mice with miRCD33 vector at an early age (2 months) was more effective at reducing Aβ plaque burden than intervening at later times (8 months). Furthermore, early intervention downregulated several microglial receptor transcripts (e.g. CD11c, CD47 and CD36) and pro-inflammatory activation genes (e.g. Tlr4 and Il1b). Marked reductions in the chemokine Ccl2 and the pro-inflammatory cytokine Tnfα were observed at the protein level in the brain of APP/PS1 mice treated with miRCD33 vector. Overall, our data indicate that CD33 is a viable target for AAV-based knockdown strategies to reduce AD pathology. One Sentence Summary: A gene therapy approach for Alzheimer's disease using adeno-associated virus vector-based knockdown of CD33 reduced amyloid beta accumulation and neuroinflammation.
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Affiliation(s)
- Ana Griciuc
- Genetics and Aging Research Unit, McCance Center for Brain Health, MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Anthony N Federico
- Genetics and Aging Research Unit, McCance Center for Brain Health, MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Jeyashree Natasan
- Molecular Neurogenetics Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02114, USA
| | - Angela M Forte
- Genetics and Aging Research Unit, McCance Center for Brain Health, MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Danielle McGinty
- Genetics and Aging Research Unit, McCance Center for Brain Health, MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Huong Nguyen
- Alzheimer's Disease Research Laboratory, MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Adrienn Volak
- Molecular Neurogenetics Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02114, USA
| | - Stanley LeRoy
- Molecular Neurogenetics Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02114, USA
| | - Sheetal Gandhi
- Alzheimer's Disease Research Laboratory, MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Eli P Lerner
- Alzheimer's Disease Research Laboratory, MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Eloise Hudry
- Alzheimer's Disease Research Laboratory, MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Rudolph E Tanzi
- Genetics and Aging Research Unit, McCance Center for Brain Health, MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Casey A Maguire
- Molecular Neurogenetics Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02114, USA
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30
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Song L, Samulski RJ, Hirsch ML. Adeno-Associated Virus Vector Mobilization, Risk Versus Reality. Hum Gene Ther 2021; 31:1054-1067. [PMID: 32829671 DOI: 10.1089/hum.2020.118] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Recombinant adeno-associated viral (rAAV) vector mobilization is a largely theoretical process in which intact AAV vectors spread or "mobilize" from transduced cells and infect additional cells within, or external of, the initial host. This process can be helper virus-independent (vector alone) or helper virus-dependent (de novo rAAV production facilitated by superinfection of both wild-type AAV [wtAAV] and Adenovirus 5 [Ad] helper virus). Herein, rAAV production and mobilization with and without wtAAV were analyzed following plasmid transfection or viral transduction utilizing well-established in vitro conditions and analytical measurements. During in vitro production, wtAAV produced the highest titer with rAAV-luc (4.1 kb), rAAV-IDUA (3.7 kb), and rAAV-Nano-dysferlin (4.9 kb) generating 2.5-, 5.9-, or 10.7-fold lower amounts, respectively. Surprisingly, cotransfection of a wtAAV and an rAAV plasmid resulted in a uniform decrease in production of wtAAV in all instances with a concomitant increase of rAAV such that wtAAV:rAAV titers were at a ratio of 1:1 for all constructs investigated. These results were shown to be independent of the rAAV transgenic sequence, size, transgene, or promoter choice and point to novel aspects of wtAAV complementation that enhance current vector production systems yet to be defined. In a mobilization assay, a sizeable amount of rAAV recovered from infected 293 cell lysate remained intact and competent for a secondary round of infection (termed Ad-independent mobilization). In rAAV-infected cells coinfected with Ad and wtAAV, rAAV particle production was increased >50-fold compared with no Ad conditions. In addition, Ad-dependent rAAV vectors mobilized and resulted in >1,000-fold transduction upon a subsequent second-round infection, highlighting the reality of these theoretical safety concerns that can be manifested under various conditions. Overall, these studies document and signify the need for mobilization-resistant vectors and the opportunity to derive better vector production systems.
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Affiliation(s)
- Liujiang Song
- Gene Therapy Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.,Department of Ophthalmology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - R Jude Samulski
- Gene Therapy Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.,Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Matthew L Hirsch
- Gene Therapy Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.,Department of Ophthalmology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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31
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AAV-mediated in vivo CAR gene therapy for targeting human T-cell leukemia. Blood Cancer J 2021; 11:119. [PMID: 34162832 PMCID: PMC8222347 DOI: 10.1038/s41408-021-00508-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 05/19/2021] [Accepted: 06/01/2021] [Indexed: 12/12/2022] Open
Abstract
Chimeric antigen receptor (CAR) T-cell therapy is the most active field in immuno-oncology and brings substantial benefit to patients with B cell malignancies. However, the complex procedure for CAR T-cell generation hampers its widespread applications. Here, we describe a novel approach in which human CAR T cells can be generated within the host upon injecting an Adeno-associated virus (AAV) vector carrying the CAR gene, which we call AAV delivering CAR gene therapy (ACG). Upon single infusion into a humanized NOD.Cg-Prkdcscid Il2rgem26/Nju tumor mouse model of human T-cell leukemia, AAV generates sufficient numbers of potent in vivo CAR cells, resulting in tumor regression; these in vivo-generated CAR cells produce antitumor immunological characteristics. This instantaneous generation of in vivo CAR T cells may bypass the need for patient lymphodepletion, as well as the β processes of traditional CAR T-cell production, which may make CAR therapy simpler and less expensive. It may allow the development of intricate, individualized treatments in the form of on-demand and diverse therapies.
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32
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Tissue and cell-type-specific transduction using rAAV vectors in lung diseases. J Mol Med (Berl) 2021; 99:1057-1071. [PMID: 34021360 DOI: 10.1007/s00109-021-02086-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 04/20/2021] [Accepted: 04/26/2021] [Indexed: 10/21/2022]
Abstract
Gene therapy of genetically determined diseases, including some pathologies of the respiratory system, requires an efficient method for transgene delivery. Recombinant adeno-associated viral (rAAV) vectors are well studied and employed in gene therapy, as they are relatively simple and low immunogenic and able to efficiently transduce eukaryotic cells. To date, many natural and artificial (with modified capsids) AAV serotypes have been isolated, demonstrating preferential tropism toward different tissues and cells in accordance with the prevalent receptors on the cell surface. However, rAAV-mediated delivery is not strictly specific due to wide tropism of some viral serotypes. Thus, the development of the methods allowing modulating specificity of these vectors could be beneficial in some cases. This review describes various approaches for retargeting rAAV to respiratory cells, for example, using different types of capsid modifications and regulation of a transgene expression by tissue-specific promoters. Part of the review is devoted to the issues of transduction of stem and progenitor lung cells using AAV, which is a complicated task today.
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Massaro G, Geard AF, Liu W, Coombe-Tennant O, Waddington SN, Baruteau J, Gissen P, Rahim AA. Gene Therapy for Lysosomal Storage Disorders: Ongoing Studies and Clinical Development. Biomolecules 2021; 11:611. [PMID: 33924076 PMCID: PMC8074255 DOI: 10.3390/biom11040611] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 04/11/2021] [Accepted: 04/13/2021] [Indexed: 12/12/2022] Open
Abstract
Rare monogenic disorders such as lysosomal diseases have been at the forefront in the development of novel treatments where therapeutic options are either limited or unavailable. The increasing number of successful pre-clinical and clinical studies in the last decade demonstrates that gene therapy represents a feasible option to address the unmet medical need of these patients. This article provides a comprehensive overview of the current state of the field, reviewing the most used viral gene delivery vectors in the context of lysosomal storage disorders, a selection of relevant pre-clinical studies and ongoing clinical trials within recent years.
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Affiliation(s)
- Giulia Massaro
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK; (A.F.G.); (W.L.); (O.C.-T.); (A.A.R.)
| | - Amy F. Geard
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK; (A.F.G.); (W.L.); (O.C.-T.); (A.A.R.)
- Wits/SAMRC Antiviral Gene Therapy Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2193, South Africa;
| | - Wenfei Liu
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK; (A.F.G.); (W.L.); (O.C.-T.); (A.A.R.)
| | - Oliver Coombe-Tennant
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK; (A.F.G.); (W.L.); (O.C.-T.); (A.A.R.)
| | - Simon N. Waddington
- Wits/SAMRC Antiviral Gene Therapy Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2193, South Africa;
- Gene Transfer Technology Group, EGA Institute for Women’s Health, University College London, London WC1E 6HX, UK
| | - Julien Baruteau
- Metabolic Medicine Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 1EH, UK;
- Great Ormond Street Hospital Biomedical Research Centre, Great Ormond Street Institute of Child Health, National Institute of Health Research, University College London, London WC1N 1EH, UK;
| | - Paul Gissen
- Great Ormond Street Hospital Biomedical Research Centre, Great Ormond Street Institute of Child Health, National Institute of Health Research, University College London, London WC1N 1EH, UK;
| | - Ahad A. Rahim
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK; (A.F.G.); (W.L.); (O.C.-T.); (A.A.R.)
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34
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Whitehead M, Osborne A, Yu-Wai-Man P, Martin K. Humoral immune responses to AAV gene therapy in the ocular compartment. Biol Rev Camb Philos Soc 2021; 96:1616-1644. [PMID: 33837614 DOI: 10.1111/brv.12718] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 03/25/2021] [Accepted: 03/25/2021] [Indexed: 12/11/2022]
Abstract
Viral vectors can be utilised to deliver therapeutic genes to diseased cells. Adeno-associated virus (AAV) is a commonly used viral vector that is favoured for its ability to infect a wide range of tissues whilst displaying limited toxicity and immunogenicity. Most humans harbour anti-AAV neutralising antibodies (NAbs) due to subclinical infections by wild-type virus during infancy and these pre-existing NAbs can limit the efficiency of gene transfer depending on the target cell type, route of administration and choice of serotype. Vector administration can also result in de novo NAb synthesis that could limit the opportunity for repeated gene transfer to diseased sites. A number of strategies have been described in preclinical models that could circumvent NAb responses in humans, however, the successful translation of these innovations into the clinical arena has been limited. Here, we provide a comprehensive review of the humoral immune response to AAV gene therapy in the ocular compartment. We cover basic AAV biology and clinical application, the role of pre-existing and induced NAbs, and possible approaches to overcoming antibody responses. We conclude with a framework for a comprehensive strategy for circumventing humoral immune responses to AAV in the future.
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Affiliation(s)
- Michael Whitehead
- John Van Geest Centre for Brain Repair, Department of Clinical Neuroscience, University of Cambridge, Cambridge, U.K
| | - Andrew Osborne
- John Van Geest Centre for Brain Repair, Department of Clinical Neuroscience, University of Cambridge, Cambridge, U.K
| | - Patrick Yu-Wai-Man
- John Van Geest Centre for Brain Repair, Department of Clinical Neuroscience, University of Cambridge, Cambridge, U.K.,MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, U.K.,NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, U.K
| | - Keith Martin
- John Van Geest Centre for Brain Repair, Department of Clinical Neuroscience, University of Cambridge, Cambridge, U.K.,Wellcome Trust-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, U.K.,Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, VIC, Australia
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35
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Pavlou M, Schön C, Occelli LM, Rossi A, Meumann N, Boyd RF, Bartoe JT, Siedlecki J, Gerhardt MJ, Babutzka S, Bogedein J, Wagner JE, Priglinger SG, Biel M, Petersen‐Jones SM, Büning H, Michalakis S. Novel AAV capsids for intravitreal gene therapy of photoreceptor disorders. EMBO Mol Med 2021; 13:e13392. [PMID: 33616280 PMCID: PMC8033523 DOI: 10.15252/emmm.202013392] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 01/14/2021] [Accepted: 01/15/2021] [Indexed: 12/12/2022] Open
Abstract
Gene therapy using recombinant adeno-associated virus (rAAV) vectors to treat blinding retinal dystrophies has become clinical reality. Therapeutically impactful targeting of photoreceptors still relies on subretinal vector delivery, which detaches the retina and harbours substantial risks of collateral damage, often without achieving widespread photoreceptor transduction. Herein, we report the development of novel engineered rAAV vectors that enable efficient targeting of photoreceptors via less invasive intravitreal administration. A unique in vivo selection procedure was performed, where an AAV2-based peptide-display library was intravenously administered in mice, followed by isolation of vector DNA from target cells after only 24 h. This stringent selection yielded novel vectors, termed AAV2.GL and AAV2.NN, which mediate widespread and high-level retinal transduction after intravitreal injection in mice, dogs and non-human primates. Importantly, both vectors efficiently transduce photoreceptors in human retinal explant cultures. As proof-of-concept, intravitreal Cnga3 delivery using AAV2.GL lead to cone-specific expression of Cnga3 protein and rescued photopic cone responses in the Cnga3-/- mouse model of achromatopsia. These novel rAAV vectors expand the clinical applicability of gene therapy for blinding human retinal dystrophies.
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Affiliation(s)
- Marina Pavlou
- Department of OphthalmologyLudwig‐Maximilians‐UniversityMunichGermany
- Centre for Integrated Protein Science Munich (CIPSM) at the Department of PharmacyLudwig‐Maximilians‐UniversityMunichGermany
| | - Christian Schön
- Centre for Integrated Protein Science Munich (CIPSM) at the Department of PharmacyLudwig‐Maximilians‐UniversityMunichGermany
| | - Laurence M Occelli
- Department of Small Animal Clinical SciencesMichigan State UniversityEast LansingMIUSA
| | - Axel Rossi
- Laboratory for Infection Biology and Gene TransferInstitute of Experimental HaematologyHannover Medical SchoolHannoverGermany
| | - Nadja Meumann
- Laboratory for Infection Biology and Gene TransferInstitute of Experimental HaematologyHannover Medical SchoolHannoverGermany
- REBIRTH Research Centre for Translational Regenerative MedicineHannover Medical SchoolHannoverGermany
| | - Ryan F Boyd
- Ophthalmology ServicesCharles River LaboratoriesMattawanMIUSA
| | - Joshua T Bartoe
- Ophthalmology ServicesCharles River LaboratoriesMattawanMIUSA
| | - Jakob Siedlecki
- Department of OphthalmologyLudwig‐Maximilians‐UniversityMunichGermany
| | | | - Sabrina Babutzka
- Department of OphthalmologyLudwig‐Maximilians‐UniversityMunichGermany
- Centre for Integrated Protein Science Munich (CIPSM) at the Department of PharmacyLudwig‐Maximilians‐UniversityMunichGermany
| | - Jacqueline Bogedein
- Department of OphthalmologyLudwig‐Maximilians‐UniversityMunichGermany
- Centre for Integrated Protein Science Munich (CIPSM) at the Department of PharmacyLudwig‐Maximilians‐UniversityMunichGermany
| | - Johanna E Wagner
- Centre for Integrated Protein Science Munich (CIPSM) at the Department of PharmacyLudwig‐Maximilians‐UniversityMunichGermany
| | | | - Martin Biel
- Centre for Integrated Protein Science Munich (CIPSM) at the Department of PharmacyLudwig‐Maximilians‐UniversityMunichGermany
| | | | - Hildegard Büning
- Laboratory for Infection Biology and Gene TransferInstitute of Experimental HaematologyHannover Medical SchoolHannoverGermany
- REBIRTH Research Centre for Translational Regenerative MedicineHannover Medical SchoolHannoverGermany
| | - Stylianos Michalakis
- Department of OphthalmologyLudwig‐Maximilians‐UniversityMunichGermany
- Centre for Integrated Protein Science Munich (CIPSM) at the Department of PharmacyLudwig‐Maximilians‐UniversityMunichGermany
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36
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Murenu E, Pavlou M, Richter L, Rapti K, Just S, Cehajic-Kapetanovic J, Tafrishi N, Hayes A, Scholey R, Lucas R, Büning H, Grimm D, Michalakis S. A universal protocol for isolating retinal ON bipolar cells across species via fluorescence-activated cell sorting. Mol Ther Methods Clin Dev 2021; 20:587-600. [PMID: 33665228 PMCID: PMC7895692 DOI: 10.1016/j.omtm.2021.01.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 01/19/2021] [Indexed: 11/17/2022]
Abstract
Inherited retinal dystrophies (IRDs) are characterized by progressive degeneration and loss of light-sensing photoreceptors. The most promising therapeutic approach for IRDs is gene supplementation therapy using viral vectors, which requires the presence of viable photoreceptors at the time of intervention. At later disease stages, photoreceptors are lost and can no longer be rescued with this approach. For these patients, conferring light-sensing abilities to the remaining interneurons of the ON circuit (i.e., ON bipolar cells) using optogenetic tools poses an alternative treatment strategy. Such treatments, however, are hampered by the lack of efficient gene delivery tools targeting ON bipolar cells, which in turn rely on the effective isolation of these cells to facilitate tool development. Herein, we describe a method to selectively isolate ON bipolar cells via fluorescence-activated cell sorting (FACS), based on the expression of two intracellular markers. We show that the method is compatible with highly sensitive downstream analyses and suitable for the isolation of ON bipolar cells from healthy as well as degenerated mouse retinas. Moreover, we demonstrate that this approach works effectively using non-human primate (NHP) retinal tissue, thereby offering a reliable pipeline for universal screening strategies that do not require inter-species adaptations or transgenic animals.
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Affiliation(s)
- Elisa Murenu
- Department of Ophthalmology, Ludwig-Maximilians-University Munich, 80336 Munich, Germany
- Department of Pharmacy, Ludwig-Maximilians-University Munich, 81377 Munich, Germany
| | - Marina Pavlou
- Department of Ophthalmology, Ludwig-Maximilians-University Munich, 80336 Munich, Germany
- Department of Pharmacy, Ludwig-Maximilians-University Munich, 81377 Munich, Germany
| | - Lisa Richter
- Core Facility Flow Cytometry, Biomedical Center, Ludwig-Maximilians-University Munich, 82152 Planegg-Martinsried, Germany
| | - Kleopatra Rapti
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, 69120 Heidelberg, Germany
- BioQuant Center, University of Heidelberg, 69120 Heidelberg, Germany
| | - Sabrina Just
- Laboratory for Infection Biology and Gene Transfer, Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
- REBIRTH Research Center for Translational Regenerative Medicine, Hannover Medical School, 30625 Hannover, Germany
| | - Jasmina Cehajic-Kapetanovic
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, Oxford University and Oxford University Hospitals, Oxford OX3 9DU, UK
| | - Neda Tafrishi
- Core Facility Flow Cytometry, Gene Center, BioSysM, Ludwig-Maximilians-University Munich, 81377 Munich, Germany
| | - Andrew Hayes
- Center for Biological Timing & School of Biological Sciences, Faculty of Biology Medicine and Health, University of Manchester, Manchester M13 9PL, UK
| | - Rachel Scholey
- Center for Biological Timing & School of Biological Sciences, Faculty of Biology Medicine and Health, University of Manchester, Manchester M13 9PL, UK
| | - Robert Lucas
- Center for Biological Timing & School of Biological Sciences, Faculty of Biology Medicine and Health, University of Manchester, Manchester M13 9PL, UK
| | - Hildegard Büning
- Laboratory for Infection Biology and Gene Transfer, Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
- REBIRTH Research Center for Translational Regenerative Medicine, Hannover Medical School, 30625 Hannover, Germany
- German Center for Infection Research (DZIF), partner site, Hannover, Germany
| | - Dirk Grimm
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, 69120 Heidelberg, Germany
- BioQuant Center, University of Heidelberg, 69120 Heidelberg, Germany
- German Center for Infection Research (DZIF) and German Center for Cardiovascular Research (DZHK), partner site, Heidelberg, Germany
| | - Stylianos Michalakis
- Department of Ophthalmology, Ludwig-Maximilians-University Munich, 80336 Munich, Germany
- Department of Pharmacy, Ludwig-Maximilians-University Munich, 81377 Munich, Germany
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37
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Rodríguez-Márquez E, Meumann N, Büning H. Adeno-associated virus (AAV) capsid engineering in liver-directed gene therapy. Expert Opin Biol Ther 2020; 21:749-766. [PMID: 33331201 DOI: 10.1080/14712598.2021.1865303] [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: 12/19/2022]
Abstract
Introduction: Gene therapy clinical trials with adeno-associated virus (AAV) vectors report impressive clinical efficacy data. Nevertheless, challenges have become apparent, such as the need for high vector doses and the induction of anti-AAV immune responses that cause the loss of vector-transduced hepatocytes. This fostered research focusing on development of next-generation AAV vectors capable of dealing with these hurdles.Areas Covered: While both the viral vector genome and the capsid are subjects to engineering, this review focuses on the latter. Specifically, we summarize the principles of capsid engineering strategies, and describe developments and applications of engineered capsid variants for liver-directed gene therapy.Expert Opinion: Capsid engineering is a promising strategy to significantly improve efficacy of the AAV vector system in clinical application. Reduction in vector dose will further improve vector safety, lower the risk of host immune responses and the cost of manufacturing. Capsid engineering is also expected to result in AAV vectors applicable to patients with preexisting immunity toward natural AAV serotypes.
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Affiliation(s)
- Esther Rodríguez-Márquez
- Universidad Autónoma De Madrid, Madrid, Spain.,Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,REBIRTH Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany
| | - Nadja Meumann
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,REBIRTH Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany
| | - Hildegard Büning
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,REBIRTH Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany.,Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany.,German Center for Infection Research (DZIF, Partner Site Hannover-Braunschweig, Germany
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38
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Journey to the Center of the Cell: Tracing the Path of AAV Transduction. Trends Mol Med 2020; 27:172-184. [PMID: 33071047 DOI: 10.1016/j.molmed.2020.09.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 09/13/2020] [Accepted: 09/15/2020] [Indexed: 02/08/2023]
Abstract
As adeno-associated virus (AAV)-based gene therapies are being increasingly approved for use in humans, it is important that we understand vector-host interactions in detail. With the advances in genome-wide genetic screening tools, a clear picture of AAV-host interactions is beginning to emerge. Understanding these interactions can provide insights into the viral life cycle. Accordingly, novel strategies to circumvent the current limitations of AAV-based vectors may be explored. Here, we summarize our current understanding of the various stages in the journey of the vector from the cell surface to the nucleus and contextualize the roles of recently identified host factors.
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Hacker UT, Bentler M, Kaniowska D, Morgan M, Büning H. Towards Clinical Implementation of Adeno-Associated Virus (AAV) Vectors for Cancer Gene Therapy: Current Status and Future Perspectives. Cancers (Basel) 2020; 12:E1889. [PMID: 32674264 PMCID: PMC7409174 DOI: 10.3390/cancers12071889] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 07/03/2020] [Accepted: 07/07/2020] [Indexed: 02/06/2023] Open
Abstract
Adeno-associated virus (AAV) vectors have gained tremendous attention as in vivo delivery systems in gene therapy for inherited monogenetic diseases. First market approvals, excellent safety data, availability of large-scale production protocols, and the possibility to tailor the vector towards optimized and cell-type specific gene transfer offers to move from (ultra) rare to common diseases. Cancer, a major health burden for which novel therapeutic options are urgently needed, represents such a target. We here provide an up-to-date overview of the strategies which are currently developed for the use of AAV vectors in cancer gene therapy and discuss the perspectives for the future translation of these pre-clinical approaches into the clinic.
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Affiliation(s)
- Ulrich T. Hacker
- Department of Oncology, Gastroenterology, Hepatology, Pulmonology, and Infectious Diseases, University Cancer Center Leipzig (UCCL), Leipzig University Medical Center, 04103 Leipzig, Germany;
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany; (M.B.); (M.M.)
| | - Martin Bentler
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany; (M.B.); (M.M.)
| | - Dorota Kaniowska
- Department of Oncology, Gastroenterology, Hepatology, Pulmonology, and Infectious Diseases, University Cancer Center Leipzig (UCCL), Leipzig University Medical Center, 04103 Leipzig, Germany;
| | - Michael Morgan
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany; (M.B.); (M.M.)
- REBIRTH Research Center for Translational Regenerative Medicine, Hannover Medical School, 30625 Hannover, Germany
| | - Hildegard Büning
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany; (M.B.); (M.M.)
- REBIRTH Research Center for Translational Regenerative Medicine, Hannover Medical School, 30625 Hannover, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Inhoffenstraße 7, 38124 Braunschweig, Germany
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40
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Meier AF, Fraefel C, Seyffert M. The Interplay between Adeno-Associated Virus and its Helper Viruses. Viruses 2020; 12:E662. [PMID: 32575422 PMCID: PMC7354565 DOI: 10.3390/v12060662] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 06/15/2020] [Accepted: 06/18/2020] [Indexed: 12/14/2022] Open
Abstract
The adeno-associated virus (AAV) is a small, nonpathogenic parvovirus, which depends on helper factors to replicate. Those helper factors can be provided by coinfecting helper viruses such as adenoviruses, herpesviruses, or papillomaviruses. We review the basic biology of AAV and its most-studied helper viruses, adenovirus type 5 (AdV5) and herpes simplex virus type 1 (HSV-1). We further outline the direct and indirect interactions of AAV with those and additional helper viruses.
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Affiliation(s)
| | | | - Michael Seyffert
- Institute of Virology, University of Zurich, CH-8057 Zurich, Switzerland; (A.F.M.); (C.F.)
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41
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Pierce GF. Uncertainty in an era of transformative therapy for haemophilia: Addressing the unknowns. Haemophilia 2020; 27 Suppl 3:103-113. [PMID: 32484283 DOI: 10.1111/hae.14023] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 03/24/2020] [Indexed: 12/12/2022]
Abstract
Haemophilia is at the dawn of a new era in therapeutic management, one that can generate greater protection from bleeding and a functional cure in some individuals. Prior advances in protein engineering and monoclonal antibody technology have facilitated therapeutic options to maintain decreased risk of bleeding and less burdensome treatment. The use of gene transfer, first proposed in 1971 for monogenic diseases, is emerging as an effective long-term treatment for a variety of diseases. Transfer of functional factor VIII (FVIII) and factor IX (FIX) genes has witnessed a series of advances and setbacks since the first non-clinical experiments in animals were initiated nearly 30 years ago. More recently, multiyear therapeutic levels of FVIII and FIX activity have been achieved in human clinical trials, translated into meaningful clinical benefit and a functional cure. While clinical progress has been definitive, many questions remain unanswered as prelicensure phase 3 clinical trials are underway. These unanswered questions translate into a state of uncertainty about the known unknowns and unknown unknowns intrinsic to any new therapeutic platform. Accepting this modality as a means to functionally cure haemophilia also means accepting the uncertainty regarding the biology of viral vector-mediated gene transfer, which remains inadequately understood. Gene therapy is a far more complex biological 'drug' than small molecule and protein drugs, where manufacturing processes and the drugs themselves are now well characterized. Extent of community acceptance of uncertainty and acknowledgement of the need for an uncompromising drive for answers to the unknowns will characterize the introduction of this first generation of gene therapy for haemophilia to the wider patient population in both resource-rich and resource-poor countries.
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Cerebral Organoids: A Human Model for AAV Capsid Selection and Therapeutic Transgene Efficacy in the Brain. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2020; 18:167-175. [PMID: 32637448 PMCID: PMC7327852 DOI: 10.1016/j.omtm.2020.05.028] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 05/27/2020] [Indexed: 12/15/2022]
Abstract
The development of gene therapies for central nervous system disorders is challenging because it is difficult to translate preclinical data from current in vitro and in vivo models to the clinic. Therefore, we developed induced pluripotent stem cell (iPSC)-derived cerebral organoids as a model for recombinant adeno-associated virus (rAAV) capsid selection and for testing efficacy of AAV-based gene therapy in a human context. Cerebral organoids are physiological 3D structures that better recapitulate the human brain compared with 2D cell lines. To validate the model, we compared the transduction efficiency and distribution of two commonly used AAV serotypes (rAAV5 and rAAV9). In cerebral organoids, transduction with rAAV5 led to higher levels of vector DNA, transgenic mRNA, and protein expression as compared with rAAV9. The superior transduction of rAAV5 was replicated in iPSC-derived neuronal cells. Furthermore, rAAV5-mediated delivery of a human sequence-specific engineered microRNA to cerebral organoids led to a lower expression of its target ataxin-3. Our studies provide a new tool for selecting and deselecting AAV serotypes, and for demonstrating therapeutic efficacy of transgenes in a human context. Implementing cerebral organoids during gene therapy development could reduce the usage of animal models and improve translation to the clinic.
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43
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An essential N-terminal serine-rich motif in the AAV VP1 and VP2 subunits that may play a role in viral transcription. Virology 2020; 546:127-132. [PMID: 32452411 DOI: 10.1016/j.virol.2020.04.008] [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] [Received: 02/18/2020] [Revised: 04/12/2020] [Accepted: 04/13/2020] [Indexed: 11/23/2022]
Abstract
Adeno-associated virus (AAV) is one of the most researched, clinically utilized gene therapy vectors. Though clinical success has been achieved, transgene delivery and expression may be hindered by cellular and tissue barriers. Understanding the role of receptor binding, entry, endosomal escape, cytoplasmic and nuclear trafficking, capsid uncoating, and viral transcription in therapeutic efficacy is paramount. Previous studies have shown that N-terminal regions of the AAV capsid proteins are responsible for endosomal escape and nuclear trafficking, however the mechanisms remain unknown. We identified a highly-conserved three-residue serine/threonine (S/T) motif in the capsid N-terminus, previously uncharacterized in its role in intracellular trafficking and transduction. Using alanine scanning mutagenesis, we found S155 and the flanking residues, D154 and G158, are essential for AAV2 transduction efficiency. Remarkably, specific capsid mutants show a 5 to 9-fold decrease in viral mRNA transcripts, highlighting a potential role of the S/T motif in transcription of the viral genome.
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44
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Maurer AC, Weitzman MD. Adeno-Associated Virus Genome Interactions Important for Vector Production and Transduction. Hum Gene Ther 2020; 31:499-511. [PMID: 32303138 PMCID: PMC7232694 DOI: 10.1089/hum.2020.069] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Accepted: 04/16/2020] [Indexed: 12/12/2022] Open
Abstract
Recombinant adeno-associated virus has emerged as one of the most promising gene therapy delivery vectors. Development of these vectors took advantage of key features of the wild-type adeno-associated virus (AAV), enabled by basic studies of the underlying biology and requirements for transcription, replication, and packaging of the viral genome. Each step in generating and utilizing viral vectors involves numerous molecular interactions that together determine the efficiency of vector production and gene delivery. Once delivered into the cell, interactions with host proteins will determine the fate of the viral genome, and these will impact the intended goal of gene delivery. Here, we provide an overview of known interactions of the AAV genome with viral and cellular proteins involved in its amplification, packaging, and expression. Further appreciation of how the AAV genome interacts with host factors will enhance how this simple virus can be harnessed for an array of vector purposes that benefit human health.
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Affiliation(s)
- Anna C. Maurer
- Department of Molecular and Cell Biology, University of California, Berkeley, California, USA
| | - Matthew D. Weitzman
- Division of Protective Immunity, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Division of Cancer Pathobiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
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45
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Zhang L, Rossi A, Lange L, Meumann N, Koitzsch U, Christie K, Nesbit MA, Moore CBT, Hacker UT, Morgan M, Hoffmann D, Zengel J, Carette JE, Schambach A, Salvetti A, Odenthal M, Büning H. Capsid Engineering Overcomes Barriers Toward Adeno-Associated Virus Vector-Mediated Transduction of Endothelial Cells. Hum Gene Ther 2020; 30:1284-1296. [PMID: 31407607 DOI: 10.1089/hum.2019.027] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Endothelial cells (EC) are targets in gene therapy and regenerative medicine, but they are inefficiently transduced with adeno-associated virus (AAV) vectors of various serotypes. To identify barriers hampering efficient transduction and to develop an optimized AAV variant for EC transduction, we screened an AAV serotype 2-based peptide display library on primary human macrovascular EC. Using a new high-throughput selection and monitoring protocol, we identified a capsid variant, AAV-VEC, which outperformed the parental serotype as well as first-generation targeting vectors in EC transduction. AAV vector uptake was improved, resulting in significantly higher transgene expression levels from single-stranded vector genomes detectable within a few hours post-transduction. Notably, AAV-VEC transduced not only proliferating EC but also quiescent EC, although higher particle-per-cell ratios had to be applied. Also, induced pluripotent stem cell-derived endothelial progenitor cells, a novel tool in regenerative medicine and gene therapy, were highly susceptible toward AAV-VEC transduction. Thus, overcoming barriers by capsid engineering significantly expands the AAV tool kit for a wide range of applications targeting EC.
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Affiliation(s)
- L Zhang
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.,Institute of Pathology, University Hospital of Cologne, Cologne, Germany
| | - A Rossi
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,International Center for Research in Infectiology (CIRI), INSERM U1111, CNRS UMR5308, Lyon, France
| | - L Lange
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,REBIRTH Cluster of Excellence, Hannover Medical School, Hannover, Germany
| | - N Meumann
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.,Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany
| | - U Koitzsch
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.,Institute of Pathology, University Hospital of Cologne, Cologne, Germany
| | - K Christie
- Biomedical Sciences Research Institute, Ulster University, Ulster, Northern Ireland
| | - M A Nesbit
- Biomedical Sciences Research Institute, Ulster University, Ulster, Northern Ireland
| | - C B T Moore
- Biomedical Sciences Research Institute, Ulster University, Ulster, Northern Ireland.,Avellino Labs USA, Menlo Park, California
| | - U T Hacker
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,1st Medical Department, University Cancer Center Leipzig, University Leipzig Medical Center, Leipzig, Germany
| | - M Morgan
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,REBIRTH Cluster of Excellence, Hannover Medical School, Hannover, Germany
| | - D Hoffmann
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,REBIRTH Cluster of Excellence, Hannover Medical School, Hannover, Germany
| | - J Zengel
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California
| | - J E Carette
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California
| | - A Schambach
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,REBIRTH Cluster of Excellence, Hannover Medical School, Hannover, Germany.,Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - A Salvetti
- International Center for Research in Infectiology (CIRI), INSERM U1111, CNRS UMR5308, Lyon, France
| | - M Odenthal
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.,Institute of Pathology, University Hospital of Cologne, Cologne, Germany
| | - H Büning
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.,Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,REBIRTH Cluster of Excellence, Hannover Medical School, Hannover, Germany.,German Center for Infection Research (DZIF), Partner Sites Bonn-Cologne and Hannover-Braunschweig, Braunschweig, Germany
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46
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Verdera HC, Kuranda K, Mingozzi F. AAV Vector Immunogenicity in Humans: A Long Journey to Successful Gene Transfer. Mol Ther 2020; 28:723-746. [PMID: 31972133 PMCID: PMC7054726 DOI: 10.1016/j.ymthe.2019.12.010] [Citation(s) in RCA: 344] [Impact Index Per Article: 86.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 12/27/2019] [Indexed: 12/15/2022] Open
Abstract
Gene therapy with adeno-associated virus (AAV) vectors has demonstrated safety and long-term efficacy in a number of trials across target organs, including eye, liver, skeletal muscle, and the central nervous system. Since the initial evidence that AAV vectors can elicit capsid T cell responses in humans, which can affect the duration of transgene expression, much progress has been made in understanding and modulating AAV vector immunogenicity. It is now well established that exposure to wild-type AAV results in priming of the immune system against the virus, with development of both humoral and T cell immunity. Aside from the neutralizing effect of antibodies, the impact of pre-existing immunity to AAV on gene transfer is still poorly understood. Herein, we review data emerging from clinical trials across a broad range of gene therapy applications. Common features of immune responses to AAV can be found, suggesting, for example, that vector immunogenicity is dose-dependent, and that innate immunity plays an important role in the outcome of gene transfer. A range of host-specific factors are also likely to be important, and a comprehensive understanding of the mechanisms driving AAV vector immunogenicity in humans will be key to unlocking the full potential of in vivo gene therapy.
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Affiliation(s)
- Helena Costa Verdera
- Genethon and INSERM U951, 91000 Evry, France; Sorbonne Université and INSERM U974, 75013 Paris, France
| | | | - Federico Mingozzi
- Genethon and INSERM U951, 91000 Evry, France; Spark Therapeutics, Philadelphia, PA 19104, USA.
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47
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Westhaus A, Cabanes-Creus M, Rybicki A, Baltazar G, Navarro RG, Zhu E, Drouyer M, Knight M, Albu RF, Ng BH, Kalajdzic P, Kwiatek M, Hsu K, Santilli G, Gold W, Kramer B, Gonzalez-Cordero A, Thrasher AJ, Alexander IE, Lisowski L. High-Throughput In Vitro, Ex Vivo, and In Vivo Screen of Adeno-Associated Virus Vectors Based on Physical and Functional Transduction. Hum Gene Ther 2020; 31:575-589. [PMID: 32000541 PMCID: PMC7232709 DOI: 10.1089/hum.2019.264] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Adeno-associated virus (AAV) vectors are quickly becoming the vectors of choice for therapeutic gene delivery. To date, hundreds of natural isolates and bioengineered variants have been reported. While factors such as high production titer and low immunoreactivity are important to consider, the ability to deliver the genetic payload (physical transduction) and to drive high transgene expression (functional transduction) remains the most important feature when selecting AAV variants for clinical applications. Reporter expression assays are the most commonly used methods for determining vector fitness. However, such approaches are time consuming and become impractical when evaluating a large number of variants. Limited access to primary human tissues or challenging model systems further complicates vector testing. To address this problem, convenient high-throughput methods based on next-generation sequencing (NGS) are being developed. To this end, we built an AAV Testing Kit that allows inherent flexibility in regard to number and type of AAV variants included, and is compatible with in vitro, ex vivo, and in vivo applications. The Testing Kit presented here consists of a mix of 30 known AAVs where each variant encodes a CMV-eGFP cassette and a unique barcode in the 3′-untranslated region of the eGFP gene, allowing NGS-barcode analysis at both the DNA and RNA/cDNA levels. To validate the AAV Testing Kit, individually packaged barcoded variants were mixed at an equal ratio and used to transduce cells/tissues of interest. DNA and RNA/cDNA were extracted and subsequently analyzed by NGS to determine the physical/functional transduction efficiencies. We were able to assess the transduction efficiencies of immortalized cells, primary cells, and induced pluripotent stem cells in vitro, as well as in vivo transduction in naïve mice and a xenograft liver model. Importantly, while our data validated previously reported transduction characteristics of individual capsids, we also identified novel previously unknown tropisms for some AAV variants.
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Affiliation(s)
- Adrian Westhaus
- Translational Vectorology Research Unit, Children's Medical Research Institute, The University of Sydney, Westmead, Australia.,Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Marti Cabanes-Creus
- Translational Vectorology Research Unit, Children's Medical Research Institute, The University of Sydney, Westmead, Australia
| | - Arkadiusz Rybicki
- Translational Vectorology Research Unit, Children's Medical Research Institute, The University of Sydney, Westmead, Australia
| | - Grober Baltazar
- Translational Vectorology Research Unit, Children's Medical Research Institute, The University of Sydney, Westmead, Australia
| | - Renina Gale Navarro
- Translational Vectorology Research Unit, Children's Medical Research Institute, The University of Sydney, Westmead, Australia
| | - Erhua Zhu
- Gene Therapy Research Unit, Children's Medical Research Institute and Sydney Children's Hospitals Network, The University of Sydney, Westmead, Australia
| | - Matthieu Drouyer
- Translational Vectorology Research Unit, Children's Medical Research Institute, The University of Sydney, Westmead, Australia
| | - Maddison Knight
- Vector and Genome Engineering Facility, Children's Medical Research Institute, , The University of Sydney, Westmead, Australia
| | - Razvan F Albu
- Vector and Genome Engineering Facility, Children's Medical Research Institute, , The University of Sydney, Westmead, Australia
| | - Boaz H Ng
- Vector and Genome Engineering Facility, Children's Medical Research Institute, , The University of Sydney, Westmead, Australia
| | - Predrag Kalajdzic
- Vector and Genome Engineering Facility, Children's Medical Research Institute, , The University of Sydney, Westmead, Australia
| | - Magdalena Kwiatek
- Military Institute of Hygiene and Epidemiology, The Biological Threats Identification and Countermeasure Centre, Puławy, Poland
| | - Kenneth Hsu
- Children's Cancer Research Unit, The Children's Hospital at Westmead, Westmead, Australia
| | - Giorgia Santilli
- Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Wendy Gold
- Molecular Neurobiology Research Lab, The Children's Hospital at Westmead, Westmead, Australia.,Discipline of Child and Adolescent Health, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia.,Kids Neuroscience Centre, Kids Research, The Children's Hospital at Westmead, Westmead, Australia
| | - Belinda Kramer
- Children's Cancer Research Unit, The Children's Hospital at Westmead, Westmead, Australia
| | - Anai Gonzalez-Cordero
- Stem Cell & Organoid Facility and Stem Cell Medicine Group, Children's Medical Research Institute, Faculty of Medicine and Health, The University of Sydney, Westmead, Australia
| | - Adrian J Thrasher
- Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Ian E Alexander
- Gene Therapy Research Unit, Children's Medical Research Institute and Sydney Children's Hospitals Network, The University of Sydney, Westmead, Australia.,Discipline of Child and Adolescent Health, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
| | - Leszek Lisowski
- Translational Vectorology Research Unit, Children's Medical Research Institute, The University of Sydney, Westmead, Australia.,Vector and Genome Engineering Facility, Children's Medical Research Institute, , The University of Sydney, Westmead, Australia.,Military Institute of Hygiene and Epidemiology, The Biological Threats Identification and Countermeasure Centre, Puławy, Poland
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48
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Krotova K, Day A, Aslanidi G. An Engineered AAV6-Based Vaccine Induces High Cytolytic Anti-Tumor Activity by Directly Targeting DCs and Improves Ag Presentation. Mol Ther Oncolytics 2019; 15:166-177. [PMID: 31720373 PMCID: PMC6838889 DOI: 10.1016/j.omto.2019.10.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 10/01/2019] [Indexed: 12/30/2022] Open
Abstract
We have previously shown that an AAV6-based vaccine generates high levels of antigen-specific CD8+ T cells. Further modifications described here led to significantly increased levels of antigen-specific CD8+ and CD4+ T cells, enhanced formation of memory cells, and superior antigen-specific killing capacity in a murine model. By tracking reporter-gene-positive dendritic cells, we showed that they were directly targeted with modified AAV6 in vivo. Our vaccine's anti-cancer potential was evaluated with the antigen ovalbumin against a B16F10 melanoma cell line stably expressing ovalbumin. The vaccination showed superior protection in a murine model of metastatic melanoma. The vaccination significantly delayed solid tumor growth but did not completely prevent tumor development. We show that tumors in immunized mice escaped vaccine-induced killing by losing ovalbumin expression. The vaccine induced massive tumor infiltration with NK and CD8+ T cells with upregulated PD-1 expression. Thus, a vaccination of a combination of anti-PD-1 antibodies demonstrated significant improvement in the treatment efficacy. To summarize, we showed that a bioengineered AAV6-based vaccine elicits strong and long-lasting cellular and humoral responses against an encoded antigen. To increase AAV vaccine efficiency and mitigate tumor escape through antigen loss, we intended to target several antigens in combination with treatments targeting the tumor microenvironment.
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Affiliation(s)
- Karina Krotova
- The Hormel Institute, University of Minnesota, Austin, MN, USA
| | - Andrew Day
- The Hormel Institute, University of Minnesota, Austin, MN, USA
| | - George Aslanidi
- The Hormel Institute, University of Minnesota, Austin, MN, USA
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49
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Song L, Song Z, Fry NJ, Conatser L, Llanga T, Mei H, Kafri T, Hirsch ML. Gene Delivery to Human Limbal Stem Cells Using Viral Vectors. Hum Gene Ther 2019; 30:1336-1348. [PMID: 31392914 DOI: 10.1089/hum.2019.071] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Limbal stem cell (LSC) transplantation is a promising treatment for ocular surface diseases especially LSC deficiency. Genetic engineering represents an attractive strategy to increase the potential for success in LSC transplantations either by correcting autologous diseased LSCs or by decreasing the immunogenicity of allogeneic LSCs. Therefore, two popular viral vectors, adeno-associated viral (AAV) vector and lentiviral (LV) vector, were compared for gene delivery in human LSCs. Transduction efficiency was evaluated by flow cytometry, quantitation of viral genomes, and fluorescence microscopy after introducing eight self-complementary AAV serotypes or LV carrying a green fluorescent protein (GFP) cassette to fresh limbal epithelial cells, cultivated LSC colonies, or after corneal intrastromal injection into human explant tissue. For fresh limbal epithelial cells, AAV6 showed the highest transduction efficiency, followed by LV and AAV4 at 24 h after vector incubation, which did not directly correlate with internalized genome copy number. The colony formation efficiency, as well as colony size over time, showed no significant differences among AAV serotypes, LV, and nontreated controls. The percentage of GFP+ colonies at 14 days post-seeding was significantly higher in the LV group, which plateaued at 50% GFP+ upon serial passages. Interestingly, AAV6-treated colonies initially showed a variegated transduction phenotype with no GFP+ colonies in serial passages. Quantitative polymerase chain reaction and AAV6 capsid staining revealed that transduction was restricted to differentiated cells of LSC colonies at a post-entry step. Following central intrastromal injection of human corneas, both LV and AAV6 transduced the stroma and endothelial cells, and AAV6 also transduced cells of the epithelia. However, no transduction was observed in derived LSC colonies. The collective results demonstrate the effectiveness of LV for stable human LSC genetic engineering and an unreported phenomenon of AAV6 transduction restriction in multipotent cells derived from the human limbus.
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Affiliation(s)
- Liujiang Song
- Gene Therapy Center, University of North Carolina, Chapel Hill, North Carolina
| | - Zhenwei Song
- Department of Ophthalmology, University of North Carolina, Chapel Hill, North Carolina
| | - Nathaniel J Fry
- Department of Microbiology, University of North Carolina, Chapel Hill, North Carolina
| | - Laura Conatser
- Gene Therapy Center, University of North Carolina, Chapel Hill, North Carolina
| | - Telmo Llanga
- Gene Therapy Center, University of North Carolina, Chapel Hill, North Carolina
| | - Hua Mei
- Department of Ophthalmology, University of North Carolina, Chapel Hill, North Carolina
| | - Tal Kafri
- Gene Therapy Center, University of North Carolina, Chapel Hill, North Carolina.,Department of Microbiology, University of North Carolina, Chapel Hill, North Carolina
| | - Matthew L Hirsch
- Gene Therapy Center, University of North Carolina, Chapel Hill, North Carolina.,Department of Ophthalmology, University of North Carolina, Chapel Hill, North Carolina
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