1
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Ball JB, Frank MG, Green-Fulgham SM, Watkins LR. Use of adeno-associated viruses for transgenic modulation of microglia structure and function: A review of technical considerations and challenges. Brain Behav Immun 2024; 118:368-379. [PMID: 38471576 PMCID: PMC11103248 DOI: 10.1016/j.bbi.2024.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 02/08/2024] [Accepted: 03/03/2024] [Indexed: 03/14/2024] Open
Abstract
Microglia play a central role in the etiology of many neuropathologies. Transgenic tools are a powerful experiment approach to gain reliable and specific control over microglia function. Adeno-associated virus (AAVs) vectors are already an indispensable tool in neuroscience research. Despite ubiquitous use of AAVs and substantial interest in the role of microglia in the study of central nervous system (CNS) function and disease, transduction of microglia using AAVs is seldom reported. This review explores the challenges and advancements made in using AAVs for expressing transgenes in microglia. First, we will examine the functional anatomy of the AAV capsid, which will serve as a basis for subsequent discussions of studies exploring the relationship between capsid mutations and microglia transduction efficacy. After outlining the functional anatomy of AAVs, we will consider the experimental evidence demonstrating AAV-mediated transduction of microglia and microglia-like cell lines followed by an examination of the most promising experimental approaches identified in the literature. Finally, technical limitations will be considered in future applications of AAV experimental approaches.
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Affiliation(s)
- Jayson B Ball
- Department of Psychology and Neuroscience, and the Center for Neuroscience, University of Colorado, Boulder, CO 80309, USA.
| | - Matthew G Frank
- Department of Psychology and Neuroscience, and the Center for Neuroscience, University of Colorado, Boulder, CO 80309, USA
| | - Suzanne M Green-Fulgham
- Department of Psychology and Neuroscience, and the Center for Neuroscience, University of Colorado, Boulder, CO 80309, USA
| | - Linda R Watkins
- Department of Psychology and Neuroscience, and the Center for Neuroscience, University of Colorado, Boulder, CO 80309, USA
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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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Wang Y, Fu Q, Park SY, Lee YS, Park SY, Lee DY, Yoon S. Decoding cellular mechanism of recombinant adeno-associated virus (rAAV) and engineering host-cell factories toward intensified viral vector manufacturing. Biotechnol Adv 2024; 71:108322. [PMID: 38336188 DOI: 10.1016/j.biotechadv.2024.108322] [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: 06/11/2023] [Revised: 01/22/2024] [Accepted: 02/06/2024] [Indexed: 02/12/2024]
Abstract
Recombinant adeno-associated virus (rAAV) is one of the prominent gene delivery vehicles that has opened promising opportunities for novel gene therapeutic approaches. However, the current major viral vector production platform, triple transfection in mammalian cells, may not meet the increasing demand. Thus, it is highly required to understand production bottlenecks from the host cell perspective and engineer the cells to be more favorable and tolerant to viral vector production, thereby effectively enhancing rAAV manufacturing. In this review, we provided a comprehensive exploration of the intricate cellular process involved in rAAV production, encompassing various stages such as plasmid entry to the cytoplasm, plasmid trafficking and nuclear delivery, rAAV structural/non-structural protein expression, viral capsid assembly, genome replication, genome packaging, and rAAV release/secretion. The knowledge in the fundamental biology of host cells supporting viral replication as manufacturing factories or exhibiting defending behaviors against viral production is summarized for each stage. The control strategies from the perspectives of host cell and materials (e.g., AAV plasmids) are proposed as our insights based on the characterization of molecular features and our existing knowledge of the AAV viral life cycle, rAAV and other viral vector production in the Human embryonic kidney (HEK) cells.
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Affiliation(s)
- Yongdan Wang
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, MA 01854, United States of America
| | - Qiang Fu
- Department of Biomedical Engineering and Biotechnology, University of Massachusetts Lowell, Lowell, MA 01854, United States of America
| | - So Young Park
- Department of Pharmaceutical Sciences, University of Massachusetts Lowell, Lowell, MA 01854, United States of America
| | - Yong Suk Lee
- Department of Pharmaceutical Sciences, University of Massachusetts Lowell, Lowell, MA 01854, United States of America
| | - Seo-Young Park
- School of Chemical Engineering, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do 16419, Republic of Korea
| | - Dong-Yup Lee
- School of Chemical Engineering, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do 16419, Republic of Korea
| | - Seongkyu Yoon
- Department of Chemical Engineering, University of Massachusetts Lowell, Lowell, MA 01854, United States of America.
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4
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Huang X, Wang X, Sun Y, Li L, Li A, Xu W, Xie X, Diao Y. Bleomycin promotes rAAV2 transduction via DNA-PKcs/Artemis-mediated DNA break repair pathways. Virology 2024; 590:109959. [PMID: 38100984 DOI: 10.1016/j.virol.2023.109959] [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: 08/07/2023] [Revised: 11/17/2023] [Accepted: 11/30/2023] [Indexed: 12/17/2023]
Abstract
Because it is safe and has a simple genome, recombinant adeno-associated virus (rAAV) is an extremely appealing vector for delivery in in vivo gene therapy. However, its low transduction efficiency for some cells, limits its further application in the field of gene therapy. Bleomycin is a chemotherapeutic agent approved by the FDA whose effect on rAAV transduction has not been studied. In this study, we systematically investigated the effect of Bleomycin on the second-strand synthesis and used CRISPR/CAS9 and RNAi methods to understand the effects of Bleomycin on rAAV vector transduction, particularly the effect of DNA repair enzymes. The results showed that Bleomycin could promote rAAV2 transduction both in vivo and in vitro. Increased transduction was discovered to be a direct result of decreased cytoplasmic rAAV particle degradation and increased second-strand synthesis. TDP1, PNKP, and SETMAR are required to repair the DNA damage gap caused by Bleomycin, TDP1, PNKP, and SETMAR promote rAAV second-strand synthesis. Bleomycin induced DNA-PKcs phosphorylation and phosphorylated DNA-PKcs and Artemis promoted second-strand synthesis. The current study identifies an effective method for increasing the capability and scope of in-vivo and in-vitro rAAV applications, which can amplify cell transduction at Bleomycin concentrations. It also supplies information on combining tumor gene therapy with chemotherapy.
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Affiliation(s)
- Xiaoping Huang
- College of Chemical Engineering and Materials Sciences, Quanzhou Normal University, Quanzhou, China; Institute of Molecular Medicine, Huaqiao University, Quanzhou, China
| | - Xiao Wang
- Institute of Molecular Medicine, Huaqiao University, Quanzhou, China
| | - Yaqi Sun
- College of Chemical Engineering and Materials Sciences, Quanzhou Normal University, Quanzhou, China
| | - Ling Li
- Institute of Molecular Medicine, Huaqiao University, Quanzhou, China
| | - Anna Li
- Institute of Molecular Medicine, Huaqiao University, Quanzhou, China
| | - Wentao Xu
- College of Chemical Engineering and Materials Sciences, Quanzhou Normal University, Quanzhou, China
| | - Xiaolan Xie
- College of Chemical Engineering and Materials Sciences, Quanzhou Normal University, Quanzhou, China.
| | - Yong Diao
- Institute of Molecular Medicine, Huaqiao University, Quanzhou, China.
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5
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Kraszewska I, Sarad K, Andrysiak K, Kopacz A, Schmidt L, Krüger M, Dulak J, Jaźwa-Kusior A. Casein kinase 2 activity is a host restriction factor for AAV transduction. Mol Ther 2024; 32:84-102. [PMID: 37952087 PMCID: PMC10787142 DOI: 10.1016/j.ymthe.2023.11.010] [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: 03/17/2023] [Revised: 09/29/2023] [Accepted: 11/09/2023] [Indexed: 11/14/2023] Open
Abstract
So far, the mechanisms that impede AAV transduction, especially in the human heart, are poorly understood, hampering the introduction of new, effective gene therapy strategies. Therefore, the aim of this study was to identify and overcome the main cellular barriers to successful transduction in the heart, using induced pluripotent stem cell (iPSC)-derived cardiomyocytes (iPSC-CMs), iPSC-derived cardiac fibroblasts (iPSC-CFs), and primary endothelial cells to model vector-host interactions. Through phosphoproteome analysis we established that casein kinase 2 (CK2) signaling is one of the most significantly affected pathways upon AAV exposure. Transient inhibition of CK2 activity substantially enhanced the transduction rate of AAV2, AAV6, and AAV9 in all tested cell types. In particular, CK2 inhibition improved the trafficking of AAVs through the cytoplasm, impaired DNA damage response through destabilization of MRE11, and altered the RNA processing pathways, which were also highly responsive to AAV transduction. Also, it augmented transgene expression in already transduced iPSC-CFs, which retain AAV genomes in a functional, but probably silent form. In summary, the present study provides new insights into the current understanding of the host-AAV vector interaction, identifying CK2 activity as a key barrier to efficient transduction and transgene expression, which may translate to improving the outcome of AAV-based therapies in the future.
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Affiliation(s)
- Izabela Kraszewska
- Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland.
| | - Katarzyna Sarad
- Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland; Doctoral School of Exact and Natural Sciences, Jagiellonian University, Krakow, Poland
| | - Kalina Andrysiak
- Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Aleksandra Kopacz
- Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Luisa Schmidt
- CECAD Research Center, Institute for Genetics, University of Cologne, Cologne, Germany
| | - Marcus Krüger
- CECAD Research Center, Institute for Genetics, University of Cologne, Cologne, Germany
| | - Józef Dulak
- Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Agnieszka Jaźwa-Kusior
- Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland.
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6
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Liu S, Chowdhury EA, Xu V, Jerez A, Mahmood L, Ly BQ, Le HK, Nguyen A, Rajwade A, Meno-Tetang G, Shah DK. Whole-Body Disposition and Physiologically Based Pharmacokinetic Modeling of Adeno-Associated Viruses and the Transgene Product. J Pharm Sci 2024; 113:141-157. [PMID: 37805073 DOI: 10.1016/j.xphs.2023.10.005] [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: 08/25/2023] [Revised: 10/02/2023] [Accepted: 10/02/2023] [Indexed: 10/09/2023]
Abstract
To facilitate model-informed drug development (MIDD) of adeno-associated virus (AAV) therapy, here we have developed a physiologically based pharmacokinetic (PBPK) model for AAVs following preclinical investigation in mice. After 2E11 Vg/mouse dose of AAV8 and AAV9 encoding a monoclonal antibody (mAb) gene, whole-body disposition of both the vector and the transgene mAb was evaluated over 3 weeks. At steady-state, the following tissue-to-blood (T/B) concentration ratios were found for AAV8/9: ∼50 for liver; ∼10 for heart and muscle; ∼2 for brain, lung, kidney, adipose, and spleen; ≤1 for bone, skin, and pancreas. T/B values for mAb were compared with the antibody biodistribution coefficients, and five different clusters of organs were identified based on their transgene expression profile. All the biodistribution data were used to develop a novel AAV PBPK model that incorporates: (i) whole-body distribution of the vector; (ii) binding, internalization, and intracellular processing of the vector; (iii) transgene expression and secretion; and (iv) whole-body disposition of the secreted transgene product. The model was able to capture systemic and tissue PK of the vector and the transgene-produced mAb reasonably well. Pathway analysis of the PBPK model suggested that liver, muscle, and heart are the main contributors for the secreted transgene mAb. Unprecedented PK data and the novel PBPK model developed here provide the foundation for quantitative systems pharmacology (QSP) investigations of AAV-mediated gene therapies. The PBPK model can also serve as a quantitative tool for preclinical study design and preclinical-to-clinical translation of AAV-based gene therapies.
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Affiliation(s)
- Shufang Liu
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States
| | - Ekram Ahmed Chowdhury
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States
| | - Vivian Xu
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States
| | - Anthony Jerez
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States
| | - Leeha Mahmood
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States
| | - Bao Quoc Ly
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States
| | - Huyen Khanh Le
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States
| | - Anne Nguyen
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States
| | - Aneesh Rajwade
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States
| | - Guy Meno-Tetang
- Neuroscience, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom
| | - Dhaval K Shah
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, The State University of New York at Buffalo, Buffalo, NY, United States.
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7
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Fu Y, Choudhary D, Liu N, Moon Y, Abdubek P, Sweezy L, Rosconi M, Palackal N, Pyles E. Comprehensive biophysical characterization of AAV-AAVR interaction uncovers serotype- and pH-dependent interaction. J Pharm Biomed Anal 2023; 234:115562. [PMID: 37441888 DOI: 10.1016/j.jpba.2023.115562] [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: 05/05/2023] [Revised: 06/29/2023] [Accepted: 07/03/2023] [Indexed: 07/15/2023]
Abstract
After more than two decades of research and development, adeno-associated virus (AAV) has become one of the dominant delivery vectors in gene therapy. Despite the focused research, the cell entry pathway for AAV is still not fully understood. Universal AAV receptor (AAVR) has been identified to be involved in cellular entry of different AAV serotypes. With the unveiling of the high-resolution AAV-AAVR complex structure by cryogenic electron microscopy, the atomic level interaction between AAV and AAVR has become the focus of study in recent years. However, the serotype dependence of this binding interaction and the effect of pH have not been studied. Here, orthogonal approaches including bio-layer interferometry (BLI), size-exclusion chromatography coupled to multi-angle laser scattering (SEC-MALS) and sedimentation velocity analytical ultracentrifugation (SV-AUC) were utilized to study the interaction between selected AAV serotypes and AAVR under different pH conditions. A robust BLI method was developed and the equilibrium dissociation binding constants (KD) between different AAV serotypes (AAV1, AAV5 and AAV8) and AAVR was measured. The binding constants measured by BLI together with orthogonal methods (SEC-MALS and SV-AUC) all confirmed that AAV5 has the strongest binding affinity followed by AAV1 while AAV8 binds the weakest. It was also observed that lower pH promotes the binding between AAV and AAVR and neutral or slightly basic conditions lead to very weak binding. These data indicate that for certain serotypes, AAVR may play a prominent role in trafficking AAV to the Golgi rather than acting as a host cell receptor. Information obtained from these combinatorial biophysical methods can be used to engineer future generations of AAVs to have better transduction efficiency.
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Affiliation(s)
- Yue Fu
- Protein Biochemistry, Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Deepanshu Choudhary
- Protein Biochemistry, Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Nina Liu
- Protein Biochemistry, Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Youmi Moon
- Protein Biochemistry, Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Polat Abdubek
- Protein Biochemistry, Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Laura Sweezy
- Protein Biochemistry, Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Michael Rosconi
- Protein Biochemistry, Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Nisha Palackal
- Protein Biochemistry, Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA.
| | - Erica Pyles
- Protein Biochemistry, Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
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8
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Maguire CA. Accessorizing viral vectors with extracellular vesicles for enhanced performance. Mol Ther 2023; 31:1204-1206. [PMID: 37044086 PMCID: PMC10188910 DOI: 10.1016/j.ymthe.2023.03.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 03/29/2023] [Accepted: 03/29/2023] [Indexed: 04/14/2023] Open
Affiliation(s)
- Casey A Maguire
- Harvard Medical School, The Massachusetts General Hospital, Boston, MA, USA.
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9
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Sarkar S, Panikker P, D’Souza S, Shetty R, Mohan RR, Ghosh A. Corneal Regeneration Using Gene Therapy Approaches. Cells 2023; 12:1280. [PMID: 37174680 PMCID: PMC10177166 DOI: 10.3390/cells12091280] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 04/13/2023] [Accepted: 04/23/2023] [Indexed: 05/15/2023] Open
Abstract
One of the most remarkable advancements in medical treatments of corneal diseases in recent decades has been corneal transplantation. However, corneal transplants, including lamellar strategies, have their own set of challenges, such as graft rejection, delayed graft failure, shortage of donor corneas, repeated treatments, and post-surgical complications. Corneal defects and diseases are one of the leading causes of blindness globally; therefore, there is a need for gene-based interventions that may mitigate some of these challenges and help reduce the burden of blindness. Corneas being immune-advantaged, uniquely avascular, and transparent is ideal for gene therapy approaches. Well-established corneal surgical techniques as well as their ease of accessibility for examination and manipulation makes corneas suitable for in vivo and ex vivo gene therapy. In this review, we focus on the most recent advances in the area of corneal regeneration using gene therapy and on the strategies involved in the development of such therapies. We also discuss the challenges and potential of gene therapy for the treatment of corneal diseases. Additionally, we discuss the translational aspects of gene therapy, including different types of vectors, particularly focusing on recombinant AAV that may help advance targeted therapeutics for corneal defects and diseases.
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Affiliation(s)
- Subhradeep Sarkar
- GROW Research Laboratory, Narayana Nethralaya Foundation, Bangalore 560099, Karnataka, India
- Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Priyalakshmi Panikker
- GROW Research Laboratory, Narayana Nethralaya Foundation, Bangalore 560099, Karnataka, India
| | - Sharon D’Souza
- Department of Cornea and Refractive Surgery, Narayana Nethralaya, Bangalore 560010, Karnataka, India
| | - Rohit Shetty
- Department of Cornea and Refractive Surgery, Narayana Nethralaya, Bangalore 560010, Karnataka, India
| | - Rajiv R. Mohan
- Harry S. Truman Memorial Veterans’ Hospital, Columbia, MO 65201, USA
- One-Health Vision Research Program, Departments of Veterinary Medicine and Surgery and Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
- Mason Eye Institute, School of Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Arkasubhra Ghosh
- GROW Research Laboratory, Narayana Nethralaya Foundation, Bangalore 560099, Karnataka, India
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Ghauri MS, Ou L. AAV Engineering for Improving Tropism to the Central Nervous System. BIOLOGY 2023; 12:biology12020186. [PMID: 36829465 PMCID: PMC9953251 DOI: 10.3390/biology12020186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 01/21/2023] [Accepted: 01/24/2023] [Indexed: 01/28/2023]
Abstract
Adeno-associated virus (AAV) is a non-pathogenic virus that mainly infects primates with the help of adenoviruses. AAV is being widely used as a delivery vector for in vivo gene therapy, as evidenced by five currently approved drugs and more than 255 clinical trials across the world. Due to its relatively low immunogenicity and toxicity, sustained efficacy, and broad tropism, AAV holds great promise for treating many indications, including central nervous system (CNS), ocular, muscular, and liver diseases. However, low delivery efficiency, especially for the CNS due to the blood-brain barrier (BBB), remains a significant challenge for more clinical application of AAV gene therapy. Thus, there is an urgent need for utilizing AAV engineering to discover next-generation capsids with improved properties, e.g., enhanced BBB penetrance, lower immunogenicity, and higher packaging efficiency. AAV engineering methods, including directed evolution, rational design, and in silico design, have been developed, resulting in the discovery of novel capsids (e.g., PhP.B, B10, PAL1A/B/C). In this review, we discuss key studies that identified engineered CNS capsids and/or established methodological improvements. Further, we also discussed important issues that need to be addressed, including cross-species translatability, cell specificity, and modular engineering to improve multiple properties simultaneously.
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Affiliation(s)
- Muhammad S. Ghauri
- School of Medicine, California University of Science and Medicine, Colton, CA 92324, USA
| | - Li Ou
- Genemagic Biosciences, Media, PA 19086, USA
- Department of Pediatrics, University of Minnesota, Minneapolis, MN 55454, USA
- Correspondence:
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11
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Hoad M, Cross EM, Donnelly CM, Sarker S, Roby JA, Forwood JK. Structural Characterization of Porcine Adeno-Associated Virus Capsid Protein with Nuclear Trafficking Protein Importin Alpha Reveals a Bipartite Nuclear Localization Signal. Viruses 2023; 15:v15020315. [PMID: 36851528 PMCID: PMC9964314 DOI: 10.3390/v15020315] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/11/2023] [Accepted: 01/17/2023] [Indexed: 01/24/2023] Open
Abstract
Adeno-associated viruses (AAV) are important vectors for gene therapy, and accordingly, many aspects of their cell transduction pathway have been well characterized. However, the specific mechanisms that AAV virions use to enter the host nucleus remain largely unresolved. We therefore aimed to reveal the interactions between the AAV Cap protein and the nuclear transport protein importin alpha (IMPα) at an atomic resolution. Herein we expanded upon our earlier research into the Cap nuclear localization signal (NLS) of a porcine AAV isolate, by examining the influence of upstream basic regions (BRs) towards IMPα binding. Using a high-resolution crystal structure, we identified that the IMPα binding determinants of the porcine AAV Cap comprise a bipartite NLS with an N-terminal BR binding at the minor site of IMPα, and the previously identified NLS motif binding at the major site. Quantitative assays showed a vast difference in binding affinity between the previously determined monopartite NLS, and bipartite NLS described in this study. Our results provide a detailed molecular view of the interaction between AAV capsids and the nuclear import receptor, and support the findings that AAV capsids enter the nucleus by binding the nuclear import adapter IMPα using the classical nuclear localization pathway.
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Affiliation(s)
- Mikayla Hoad
- School of Dentistry and Medical Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia
| | - Emily M. Cross
- School of Dentistry and Medical Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia
| | - Camilla M. Donnelly
- School of Dentistry and Medical Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia
| | - Subir Sarker
- Department of Microbiology, Anatomy, Physiology and Pharmacology, School of Agriculture, Biomedicine and Environment, La Trobe University, Melbourne, VIC 3086, Australia
| | - Justin A. Roby
- School of Dentistry and Medical Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia
| | - Jade K. Forwood
- School of Dentistry and Medical Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia
- Correspondence:
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12
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Han Z, Luo N, Wu Y, Kou J, Ma W, Yang X, Cai Y, Ma L, Han L, Wang X, Qin H, Shi Q, Wang J, Ye C, Lin K, Xu F. AAV13 Enables Precise Targeting of Local Neural Populations. Int J Mol Sci 2022; 23:12806. [PMID: 36361595 PMCID: PMC9653909 DOI: 10.3390/ijms232112806] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 10/17/2022] [Accepted: 10/21/2022] [Indexed: 09/05/2023] Open
Abstract
As powerful tools for local gene delivery, adeno-associated viruses (AAVs) are widely used for neural circuit studies and therapeutical purposes. However, most of them have the characteristics of large diffusion range and retrograde labeling, which may result in off-target transduction during in vivo application. Here, in order to achieve precise gene delivery, we screened AAV serotypes that have not been commonly used as gene vectors and found that AAV13 can precisely transduce local neurons in the brain, with a smaller diffusion range than AAV2 and rigorous anterograde labeling. Then, AAV13-based single-viral and dual-viral strategies for sparse labeling of local neurons in the brains of C57BL/6 or Cre transgenic mice were developed. Additionally, through the neurobehavioral test in the ventral tegmental area, we demonstrated that AAV13 was validated for functional monitoring by means of carrying Cre recombinase to drive the expression of Cre-dependent calcium-sensitive indicator. In summary, our study provides AAV13-based toolkits for precise local gene delivery, which can be used for in situ small nuclei targeting, sparse labeling and functional monitoring.
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Affiliation(s)
- Zengpeng Han
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Shenzhen Key Laboratory of Viral Vectors for Biomedicine, Key Laboratory of Quality Control Technology for Virus-Based Therapeutics, Guangdong Provincial Medical Products Administration, NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen 518055, China
| | - Nengsong Luo
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Yang Wu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiaxin Kou
- Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Wenyu Ma
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xin Yang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Yuxiang Cai
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Lin Ma
- Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Lu Han
- College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Xiujie Wang
- College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Hualing Qin
- College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Qing Shi
- Shenzhen Key Laboratory of Viral Vectors for Biomedicine, Key Laboratory of Quality Control Technology for Virus-Based Therapeutics, Guangdong Provincial Medical Products Administration, NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen 518055, China
| | - Jie Wang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chaohui Ye
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kunzhang Lin
- Shenzhen Key Laboratory of Viral Vectors for Biomedicine, Key Laboratory of Quality Control Technology for Virus-Based Therapeutics, Guangdong Provincial Medical Products Administration, NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen 518055, China
| | - Fuqiang Xu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Shenzhen Key Laboratory of Viral Vectors for Biomedicine, Key Laboratory of Quality Control Technology for Virus-Based Therapeutics, Guangdong Provincial Medical Products Administration, NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen 518055, China
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China
- Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China
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13
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Han J, Zhu L, Zhang J, Guo L, Sun X, Huang C, Xu K, Zhang Y, Li W, Zhou Q. Rational engineering of adeno-associated virus capsid enhances human hepatocyte tropism and reduces immunogenicity. Cell Prolif 2022; 55:e13339. [PMID: 36135100 DOI: 10.1111/cpr.13339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 08/25/2022] [Accepted: 08/31/2022] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVES Gene therapy based on recombinant adeno-associated viral (rAAV) vectors has been proved to be clinically effective for genetic diseases. However, there are still some limitations, including possible safety concerns for high dose delivery and a decreasing number of target patients caused by the high prevalence of pre-existing neutralizing antibodies, hindering its application. Herein, we explored whether there was an engineering strategy that can obtain mutants with enhanced transduction efficiency coupled with reduced immunogenicity. METHODS We described a new strategy for AAV capsids engineering by combining alterations of N-linked glycosylation and the mutation of PLA2-like motif. With this combined strategy, we generated novel variants derived from AAV8 and AAVS3. RESULTS The variants mediated higher transduction efficiency in human liver carcinoma cell lines and human primary hepatocytes as well as other human tissue cell lines. Importantly, all the variants screened out showed lower sensitivity to neutralizing antibody in vitro and in vivo. Moreover, the in vivo antibody profiles of variants were different from their parental AAV capsids. CONCLUSIONS Our work proposed a new combined engineering strategy and engineered two liver-tropic AAVs. We also obtained several AAV variants with a higher transduction efficiency and lower sensitivity of neutralizing antibodies. By expanding the gene delivery toolbox, these variants may further facilitate the success of AAV gene therapy.
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Affiliation(s)
- Jiabao Han
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regenerative Medicine, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Liyu Zhu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regenerative Medicine, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Jingwen Zhang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regenerative Medicine, Chinese Academy of Sciences, Beijing, China.,College of Life Science, Nankai University, Tianjin, China
| | - Lu Guo
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regenerative Medicine, Chinese Academy of Sciences, Beijing, China
| | - Xuehan Sun
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regenerative Medicine, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Cheng Huang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regenerative Medicine, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Kai Xu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regenerative Medicine, Chinese Academy of Sciences, Beijing, China.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
| | - Ying Zhang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regenerative Medicine, Chinese Academy of Sciences, Beijing, China.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
| | - Wei Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regenerative Medicine, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
| | - Qi Zhou
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Institute for Stem Cell and Regenerative Medicine, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
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14
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Nakahama R, Saito A, Nobe S, Togashi K, Suzuki IK, Uematsu A, Emoto K. The tyrosine capsid mutations on retrograde adeno-associated virus accelerates gene transduction efficiency. Mol Brain 2022; 15:70. [PMID: 35941689 PMCID: PMC9358834 DOI: 10.1186/s13041-022-00957-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 07/28/2022] [Indexed: 12/02/2022] Open
Abstract
Adeno-associated virus (AAV) vector is a critical tool for gene delivery through its durable transgene expression and safety profile. Among many serotypes, AAV2-retro is typically utilized for dissecting neural circuits with its retrograde functionality. However, this vector requires a relatively long-term incubation period (over 2 weeks) to obtain enough gene expression levels presumably due to low efficiency in gene transduction. Here, we aimed to enhance transgene expression efficiency of AAV2-retro vectors by substituting multiple tyrosine residues with phenylalanines (YF mutations) in the virus capsid, which is previously reported to improve the transduction efficiency of AAV2-infected cells by evading host cell responses. We found that AAV2-retro with YF mutations (AAV2-retroYF)-mediated transgene expression was significantly enhanced in the primary culture of murine cortical neurons at 1 week after application, comparable to that of the conventional AAV2-retro at 2 week after application. Moreover, transgene expressions in the retrogradely labeled neurons mediated by AAV2-retroYF were significantly increased both in the cortico-cortical circuits and in the subcortical circuits in vivo, while the retrograde functionality of AAV2-retroYF was equally effective as that of AAV2-retro. Our data indicate that YF mutations boost AAV2-retro-mediated retrograde gene transduction in vivo and suggest that the AAV2-retroYF should be useful for efficient targeting of the projection-defined neurons, which is suited to applications for dissecting neural circuits during development as well as future clinical applications.
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Affiliation(s)
- Ryota Nakahama
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Aika Saito
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Sensho Nobe
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Kazuya Togashi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Ikuo K Suzuki
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Akira Uematsu
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan. .,International Research Center for Neurointelligence (WPI-IRCN), The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
| | - Kazuo Emoto
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan. .,International Research Center for Neurointelligence (WPI-IRCN), The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
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15
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Ashby F, Heldermon C. The significance of triple-capsid-mutant AAV8 for treatment of Sanfilippo Syndrome Type B. ARCHIVES OF STEM CELL AND THERAPY 2022; 3:11-17. [PMID: 38596745 PMCID: PMC11003760 DOI: 10.46439/stemcell.3.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Sanfilippo Syndrome Type-B remains an untreatable childhood neurodegenerative disease with great burden for both patient and caregiver. Very few clinical trials have been undertaken to treat the disease, and none of these have yet yielded clinically obtainable products for patients. Caused by a simple enzyme function deficiency, Sanfilippo Syndrome Type-B has been considered a great prospect for gene-therapy interventions. Adeno-associated virus (AAV) remains a major choice for therapeutic gene delivery due to its relatively low-immunogenicity, versatility and tissue tropism. However, many clinical trials with AAV continue to use wild-type capsids, which in many cases are not able to reach stable transgene expression for long enough to be clinically effective in most cases. Previous research in AAV gene-therapy has created a litany of novel AAV capsids that can improve overall transduction efficiency far above that of wild-type AAV capsids. One such example is the triple-capsid mutant AAV8 (TCM8), which has been shown to exhibit transgene expression far superior to other capsids in Sanfilippo mouse models, specifically. Originally designed to bypass capsid ubiquitination intracellularly, mouse studies suggest this TCM8 vector outperforms both AAV5 and AAV9 when delivered to the central nervous system. This implies it as an ideal contender for an effective gene-therapy clinical trial candidate and has the potential to advance the progress of Sanfilippo Syndrome treatment. Here we provide commentary on the TCM8 vector and its context in the field of Sanfilippo Syndrome Type-B research.
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Affiliation(s)
- Frederick Ashby
- University of Florida, College of Medicine, Gainesville, FL 32610-0278, USA
| | - Coy Heldermon
- University of Florida, College of Medicine, Gainesville, FL 32610-0278, USA
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16
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Fakhiri J, Grimm D. Best of most possible worlds: Hybrid gene therapy vectors based on parvoviruses and heterologous viruses. Mol Ther 2021; 29:3359-3382. [PMID: 33831556 PMCID: PMC8636155 DOI: 10.1016/j.ymthe.2021.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 01/12/2021] [Accepted: 03/31/2021] [Indexed: 12/12/2022] Open
Abstract
Parvoviruses and especially the adeno-associated virus (AAV) species provide an exciting and versatile platform for the rational design or molecular evolution of human gene-therapy vectors, documented by literature from over half a century, hundreds of clinical trials, and the recent commercialization of multiple AAV gene therapeutics. For the last three decades, the power of these vectors has been further potentiated through various types of hybrid vectors created by intra- or inter-genus juxtaposition of viral DNA and protein cis elements or by synergistic complementation of parvoviral features with those of heterologous, prokaryotic, or eukaryotic viruses. Here, we provide an overview of the history and promise of this rapidly expanding field of hybrid parvoviral gene-therapy vectors, starting with early generations of chimeric particles composed of a recombinant AAV genome encapsidated in shells of synthetic AAVs or of adeno-, herpes-, baculo-, or protoparvoviruses. We then dedicate our attention to two newer, highly promising types of hybrid vectors created via (1) pseudotyping of AAV genomes with bocaviral serotypes and capsid mutants or (2) packaging of AAV DNA into, or tethering of entire vector particles to, bacteriophages. Finally, we conclude with an outlook summarizing critical requirements and improvements toward clinical translation of these original concepts.
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Affiliation(s)
- Julia Fakhiri
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, Heidelberg, Germany; BioQuant, University of Heidelberg, Heidelberg, Germany
| | - Dirk Grimm
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, Heidelberg, Germany; BioQuant, University of Heidelberg, Heidelberg, Germany; German Center for Infection Research (DZIF) and German Center for Cardiovascular Research (DZHK), Partner site Heidelberg, Heidelberg, Germany.
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17
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Bennett A, Hull J, Jolinon N, Tordo J, Moss K, Binns E, Mietzsch M, Hagemann C, Linden RM, Serio A, Chipman P, Sousa D, Broecker F, Seeberger P, Henckaerts E, McKenna R, Agbandje-McKenna M. Comparative structural, biophysical, and receptor binding study of true type and wild type AAV2. J Struct Biol 2021; 213:107795. [PMID: 34509611 PMCID: PMC9918372 DOI: 10.1016/j.jsb.2021.107795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 08/27/2021] [Accepted: 09/05/2021] [Indexed: 01/25/2023]
Abstract
Adeno-associated viruses (AAV) are utilized as gene transfer vectors in the treatment of monogenic disorders. A variant, rationally engineered based on natural AAV2 isolates, designated AAV-True Type (AAV-TT), is highly neurotropic compared to wild type AAV2 in vivo, and vectors based on it, are currently being evaluated for central nervous system applications. AAV-TT differs from AAV2 by 14 amino acids, including R585S and R588T, two residues previously shown to be essential for heparan sulfate binding of AAV2. The capsid structures of AAV-TT and AAV2 visualized by cryo-electron microscopy at 3.4 and 3.0 Å resolution, respectively, highlighted structural perturbations at specific amino acid differences. Differential scanning fluorimetry (DSF) performed at different pH conditions demonstrated that the melting temperature (Tm) of AAV2 was consistently ∼5 °C lower than AAV-TT, but both showed maximal stability at pH 5.5, corresponding to the pH in the late endosome, proposed as required for VP1u externalization to facilitate endosomal escape. Reintroduction of arginines at positions 585 and 588 in AAV-TT caused a reduction in Tm, demonstrating that the lack of basic amino acids at these positions are associated with capsid stability. These results provide structural and thermal annotation of AAV2/AAV-TT residue differences, that account for divergent cell binding, transduction, antigenic reactivity, and transduction of permissive tissues between the two viruses. Specifically, these data indicate that AAV-TT may not utilize a glycan receptor mediated pathway to enter cells and may have lower antigenic properties as compared to AAV2.
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Affiliation(s)
- Antonette Bennett
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Joshua Hull
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Nelly Jolinon
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King's College London, London SE1 9RT, UK
| | | | - Katie Moss
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Enswert Binns
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Mario Mietzsch
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Cathleen Hagemann
- Centre for Craniofacial & Regenerative Biology, King's College London, London SE19RT, UK; The Francis Crick Institute, London NW1 1AT, UK
| | | | - Andrea Serio
- Centre for Craniofacial & Regenerative Biology, King's College London, London SE19RT, UK; The Francis Crick Institute, London NW1 1AT, UK
| | - Paul Chipman
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Duncan Sousa
- Biological Science Imaging Resource, Department of Biological Sciences, Florida State University, 89 Chieftan Way Rm 119, Tallahassee, FL 32306, USA
| | - Felix Broecker
- Department of Biomolecular Systems, Max-Planck-Institute of Colloids and Interfaces, 14476 Potsdam, Germany
| | - Peter Seeberger
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany
| | - Els Henckaerts
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King's College London, London SE1 9RT, UK; Laboratory of Viral Cell Biology and Therapeutics, Department of Cellular and Molecular Medicine, Department of Microbiology, Immunology and Transplantation, KU Leuven, 3000 Leuven, Belgium.
| | - Robert McKenna
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA.
| | - Mavis Agbandje-McKenna
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
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18
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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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19
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Gilkes JA, Judkins BL, Herrera BN, Mandel RJ, Boye SL, Boye SE, Srivastava A, Heldermon CD. Site-specific modifications to AAV8 capsid yields enhanced brain transduction in the neonatal MPS IIIB mouse. Gene Ther 2021; 28:447-455. [PMID: 33244179 PMCID: PMC8149485 DOI: 10.1038/s41434-020-00206-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 09/03/2020] [Accepted: 10/19/2020] [Indexed: 12/16/2022]
Abstract
Mucopolysaccharidosis type IIIB (MPS IIIB) is an autosomal recessive lysosomal disease caused by defective production of the enzyme α-N-acetylglucosaminidase. It is characterized by severe and complex central nervous system degeneration. Effective therapies will likely target early onset disease and overcome the blood-brain barrier. Modifications of adeno-associated viral (AAV) vector capsids that enhance transduction efficiency have been described in the retina. Herein, we describe for the first time, a transduction assessment of two intracranially administered adeno-associated virus serotype 8 variants, in which specific surface-exposed tyrosine (Y) and threonine (T) residues were substituted with phenylalanine (F) and valine (V) residues, respectively. A double-mutant (Y444 + 733F) and a triple-mutant (Y444 + 733F + T494V) AAV8 were evaluated for their efficacy for the potential treatment of MPS IIIB in a neonatal setting. We evaluated biodistribution and transduction profiles of both variants compared to the unmodified parental AAV8, and assessed whether the method of vector administration would modulate their utility. Vectors were administered through four intracranial routes: six sites (IC6), thalamic (T), intracerebroventricular, and ventral tegmental area into neonatal mice. Overall, we conclude that the IC6 method resulted in the widest biodistribution within the brain. Noteworthy, we demonstrate that GFP intensity was significantly more robust with AAV8 (double Y-F + T-V) compared to AAV8 (double Y-F). This provides proof of concept for the enhanced utility of IC6 administration of the capsid modified AAV8 (double Y-F + T-V) as a valid therapeutic approach for the treatment of MPS IIIB, with further implications for other monogenic diseases.
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Affiliation(s)
- Janine A Gilkes
- Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
| | - Benjamin L Judkins
- Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
| | - Brontie N Herrera
- Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
| | - Ronald J Mandel
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL, USA
| | - Sanford L Boye
- Department of Pediatrics, Powell Gene Therapy Center, University of Florida College of Medicine, Gainesville, FL, USA
| | - Shannon E Boye
- Department of Pediatrics, Division of Cellular and Molecular Therapy, University of Florida College of Medicine, Gainesville, FL, USA
| | - Arun Srivastava
- Department of Pediatrics, Division of Cellular and Molecular Therapy, University of Florida College of Medicine, Gainesville, FL, USA
| | - Coy D Heldermon
- Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA.
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20
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AAV9 Structural Rearrangements Induced by Endosomal Trafficking pH and Glycan Attachment. J Virol 2021; 95:e0084321. [PMID: 34260280 DOI: 10.1128/jvi.00843-21] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Adeno-associated viruses (AAVs) are small non-enveloped ssDNA viruses, that are currently being developed as gene therapy biologics. After cell entry, AAVs traffic to the nucleus using the endo-lysosomal pathway. The subsequent decrease in pH triggers conformational changes to the capsid that enables the externalization of the capsid protein (VP) N-termini, including the unique domain of the minor capsid protein VP1 (VP1u), which permits phospholipase activity required for the capsid lysosomal egress. Here, we report the AAV9 capsid structure, determined at the endosomal pHs (7.4, 6.0, 5.5, and 4.0) and terminal galactose-bound AAV9 capsids at pHs 7.4 and 5.5 using cryo-electron microscopy and three-dimensional image reconstruction. Taken together these studies provide insight into AAV9 capsid conformational changes at the 5-fold pore during endosomal trafficking, both in the presence and absence of its cellular glycan receptor. We visualized, for the first time, that acidification induces the externalization of the VP3 and possibly VP2 N-termini, presumably in prelude to the externalization of VP1u at pH 4.0, that is essential for lysosomal membrane disruption. In addition, the structural study of AAV9-galactose interactions demonstrates AAV9 remains attached to its glycan receptor at the late endosome pH 5.5. This interaction significantly alters the conformational stability of the variable region I of the VPs, as well as the dynamics associated with VP N-terminus externalization. Importance There are 13 distinct Adeno-associated virus (AAV) serotypes that are structurally homologous and whose capsid proteins (VP1-3) are similar in amino acid sequence. However, AAV9 is one of the most commonly studied and used as gene therapy vector. This is part because, AAV9 is capable of crossing the blood brain barrier as well as readily transduces a wide array of tissues, including the central nervous system. In this study we provide AAV9 capsid structural insight during intracellular trafficking. Although the AAV capsid has been shown to externalize the N-termini of its VPs, to enzymatically disrupt the lysosome membrane at low pH, there was no structural evidence to confirm this. By utilizing AAV9 as our model, we provide the first structural evidence that the externalization process occurs at the protein interface at the icosahedral 5-fold symmetry axis and can be triggered by lowering pH.
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21
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Cui S, Ganjawala TH, Abrams GW, Pan ZH. Effect of Proteasome Inhibitors on the AAV-Mediated Transduction Efficiency in Retinal Bipolar Cells. Curr Gene Ther 2021; 19:404-412. [PMID: 32072884 DOI: 10.2174/1566523220666200211111326] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 01/29/2020] [Accepted: 01/30/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND Adeno-associated Virus (AAV) vectors are the most promising vehicles for therapeutic gene delivery to the retina. To develop a practical gene delivery tool, achieving high AAV transduction efficiency in specific cell types is often required. AAV-mediated targeted expression in retinal bipolar cells is needed in certain applications such as optogenetic therapy, however, the transduction efficiency driven by endogenous cell-specific promoters is usually low. Methods that can improve AAV transduction efficiency in bipolar cells need to be developed. OBJECTIVE The study aimed to examine the effect of proteasome inhibitors on AAV-mediated transduction efficiency in retinal bipolar cells. METHODS Quantitative analysis of fluorescent reporter protein expression was performed to assess the effect of two proteasome inhibitors, doxorubicin and MG132, on AAV-mediated transduction efficiency in retinal bipolar cells in mice. RESULTS Our results showed that doxorubicin can increase the AAV transduction efficiency in retinal bipolar cells in a dose-dependent manner. We also observed doxorubicin-mediated cytotoxicity in retinal neurons, but the cytotoxicity could be mitigated by the coapplication of dexrazoxane. Three months after the coapplication of doxorubicin (300 μM) and dexrazoxane, the AAV transduction efficiency in retinal bipolar cells increased by 33.8% and no cytotoxicity was observed in all the layers of the retina. CONCLUSION Doxorubicin could enhance the AAV transduction efficiency in retinal bipolar cells in vivo. The potential long-term cytotoxicity caused by doxorubicin to retinal neurons could be partially mitigated by dexrazoxane. The coapplication of doxorubicin and dexrazoxane may serve as a potential adjuvant regimen for improving AAV transduction efficiency in retinal bipolar cells.
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Affiliation(s)
- Shengjie Cui
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University, School of Medicine, Detroit, MI, 48201, United States
| | - Tushar H Ganjawala
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University, School of Medicine, Detroit, MI, 48201, United States
| | - Gary W Abrams
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University, School of Medicine, Detroit, MI, 48201, United States
| | - Zhuo-Hua Pan
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University, School of Medicine, Detroit, MI, 48201, United States
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22
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Dudek AM, Porteus MH. Answered and Unanswered Questions in Early-Stage Viral Vector Transduction Biology and Innate Primary Cell Toxicity for Ex-Vivo Gene Editing. Front Immunol 2021; 12:660302. [PMID: 34122418 PMCID: PMC8195279 DOI: 10.3389/fimmu.2021.660302] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 05/04/2021] [Indexed: 01/07/2023] Open
Abstract
Adeno-associated virus is a highly efficient DNA delivery vehicle for genome editing strategies that employ CRISPR/Cas9 and a DNA donor for homology-directed repair. Many groups have used this strategy in development of therapies for blood and immune disorders such as sickle-cell anemia and severe-combined immunodeficiency. However, recent events have called into question the immunogenicity of AAV as a gene therapy vector and the safety profile dictated by the immune response to this vector. The target cells dictating this response and the molecular mechanisms dictating cellular response to AAV are poorly understood. Here, we will investigate the current known AAV capsid and genome interactions with cellular proteins during early stage vector transduction and how these interactions may influence innate cellular responses. We will discuss the current understanding of innate immune activation and DNA damage response to AAV, and the limitations of what is currently known. In particular, we will focus on pathway differences in cell line verses primary cells, with a focus on hematopoietic stem and progenitor cells (HSPCs) in the context of ex-vivo gene editing, and what we can learn from HSPC infection by other parvoviruses. Finally, we will discuss how innate immune and DNA damage response pathway activation in these highly sensitive stem cell populations may impact long-term engraftment and clinical outcomes as these gene-editing strategies move towards the clinic, with the aim to propose pathways relevant for improved hematopoietic stem cell survival and long-term engraftment after AAV-mediated genome editing.
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Affiliation(s)
- Amanda Mary Dudek
- Department of Pediatrics, Stanford University, Stanford, CA, United States.,Department of Pediatrics, School of Medicine, Stanford University, Palo Alto, CA, United States
| | - Matthew Hebden Porteus
- Department of Pediatrics, Stanford University, Stanford, CA, United States.,Department of Pediatrics, School of Medicine, Stanford University, Palo Alto, CA, United States
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23
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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 DOI: 10.1038/s41434-021-00243-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [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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24
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Proteosomal degradation impairs transcytosis of AAV vectors from suprachoroidal space to retina. Gene Ther 2021; 28:740-747. [PMID: 33542456 PMCID: PMC8333227 DOI: 10.1038/s41434-021-00233-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 12/21/2020] [Accepted: 01/21/2021] [Indexed: 01/18/2023]
Abstract
Suprachoroidal injection provides a new route of delivery for AAV vectors to retinal pigmented epithelial cells and photoreceptors that can be done in an outpatient setting and is less invasive and potentially safer than subretinal injection, the most common route of delivery for ocular gene therapy. After suprachoroidal injection of AAV8 or AAV9 vectors, there is strong transduction of photoreceptors, but it is unclear how vector traverses the retinal pigmented epithelium. In this study, we found that transduction of photoreceptors was significantly increased after suprachoroidal injection of AAV2tYF-CBA-GFP versus AAV2-CBA-GFP vector. Compared with AAV2, AAV2tYF is more resistant to proteosomal degradation. Treatment with protease inhibitors significantly increased photoreceptor transduction after suprachoroidal injection of AAV5-GRK1-GFP. These data suggest that after suprachoroidal injection, AAV vectors access photoreceptors by transcytosis through retinal pigmented epithelial cells during which they are subject to proteosomal degradation, which if suppressed can enhance transduction of photoreceptors.
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25
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Remes A, Basha D, Frey N, Wagner A, Müller O. Gene transfer to the vascular system: Novel translational perspectives for vascular diseases. Biochem Pharmacol 2020; 182:114265. [DOI: 10.1016/j.bcp.2020.114265] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 10/01/2020] [Accepted: 10/01/2020] [Indexed: 01/04/2023]
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26
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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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27
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Breaking the sound barrier: Towards next-generation AAV vectors for gene therapy of hearing disorders. Hear Res 2020; 413:108092. [PMID: 33268240 DOI: 10.1016/j.heares.2020.108092] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 09/14/2020] [Accepted: 10/08/2020] [Indexed: 12/20/2022]
Abstract
Owing to the advances in transgenic animal technology and the advent of the next-generation sequencing era, over 120 genes causing hereditary hearing loss have been identified by now. In parallel, the field of human gene therapy continues to make exciting and rapid progress, culminating in the recent approval of several ex vivo and in vivo applications. Despite these encouraging developments and the growing interest in causative treatments for hearing disorders, gene therapeutic interventions in the inner ear remain in their infancy and await clinical translation. This review focuses on the adeno-associated virus (AAV), which nowadays represents one of the safest and most promising vectors in gene therapy. We first provide an overview of AAV biology and outline the principles of therapeutic gene transfer with recombinant AAV vectors, before pointing out major challenges and solutions for clinical translation including vector manufacturing and species translatability. Finally, we highlight seminal technologies for engineering and selection of next-generation "designer" AAV capsids, and illustrate their power and potential with recent examples of their application for inner ear gene transfer in animals.
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28
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Maurya S, Jayandharan GR. Gene Therapy: Contest between Adeno-Associated Virus and Host Cells and the Impact of UFMylation. Mol Pharm 2020; 17:3649-3653. [PMID: 32857512 DOI: 10.1021/acs.molpharmaceut.0c00512] [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: 11/29/2022]
Abstract
Adeno-associated virus (AAV)-based gene therapy is currently limited by (1) decline in therapeutic gene expression over time, (2) immune cell activation and (3) neutralization by pre-existing antibodies. Hence, studying the interaction of AAV vectors with various cellular pathways during the production and transduction process is necessary to overcome such barriers. Post-translational modifications (PTM) of AAV vectors during the production and transduction process is known to limit its transduction efficiency and further evoke the immune response. Further, AAV vectors are known to trigger cellular stress, resulting in an upregulation of distinct arms of the unfolded protein response (UPR) pathway. Recognition of the AAV genome by Toll-like receptor-9 triggers the myeloid differentiation primary response signaling cascade for innate (IL-6, IFN-α, IFN-β) and adaptive (CD8+ T-cell, B-cell) immune response against the viral capsid and the transgene product. Herein, we highlight a potential intersection of the UPR, PTMs, and intracellular trafficking pathways, which could be fine-tuned to augment the outcome of AAV-based gene delivery.
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Affiliation(s)
- Shubham Maurya
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Giridhara R Jayandharan
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
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29
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Xu Y, Guo P, Zhang J, Chrzanowski M, Chew H, Firrman JA, Sang N, Diao Y, Xiao W. Effects of Thermally Induced Configuration Changes on rAAV Genome's Enzymatic Accessibility. Mol Ther Methods Clin Dev 2020; 18:328-334. [PMID: 32671135 PMCID: PMC7338580 DOI: 10.1016/j.omtm.2020.06.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 06/03/2020] [Indexed: 11/15/2022]
Abstract
Physical titers for recombinant adeno-associated viral (rAAV) vectors are measured by quantifying viral genomes. It is generally perceived that AAV virions disassemble and release DNA upon thermal treatment. Here, we present data on enzymatic accessibility of rAAV genomes when AAV virions were subjected to thermal treatment. For rAAV vectors with a normal genome size (≤4.7 kb), thermal treatment at 75°C-99°C allowed only ∼10% of genomes to be detectable by quantitative real-time PCR. In contrast, greater than 70% of AAV genomes can be detected under similar conditions for AAV vectors with an oversized genome (≥5.0 kb). The permeability of virions, as measured by ethidium bromide (EB) staining, was enhanced by thermal stimulation. These results suggest that in rAAV virions with standard-sized genomes, the capsid and DNA are close enough in proximity for heat-induced "crosslinking," which results in inaccessibility of vector DNA to enzymatic reactions. In contrast, rAAV vectors with oversized genomes release their DNA readily upon thermal treatment. These findings suggested that the spatial arrangement of capsid protein and DNA in AAV virions is genome-size dependent. These results provide a foundation for future improvement of vector assays, design, and applications.
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Affiliation(s)
- Yinxia Xu
- School of Biomedical Science, Huaqiao University, Quanzhou, China
| | - Ping Guo
- School of Biomedical Science, Huaqiao University, Quanzhou, China
| | - Junping Zhang
- Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, IN 46202, USA
| | | | - Helen Chew
- Temple University Medical School, Philadelphia, PA 19140, USA
| | - Jenni A. Firrman
- United States Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, Wyndmoor, PA 19038, USA
| | - Nianli Sang
- Department of Biology, College of Arts and Sciences, Drexel University, Philadelphia, PA 19104, USA
| | - Yong Diao
- School of Biomedical Science, Huaqiao University, Quanzhou, China
| | - Weidong Xiao
- Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, IN 46202, USA
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30
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Carneiro A, Lee H, Lin L, van Haasteren J, Schaffer DV. Novel Lung Tropic Adeno-Associated Virus Capsids for Therapeutic Gene Delivery. Hum Gene Ther 2020; 31:996-1009. [PMID: 32799685 DOI: 10.1089/hum.2020.169] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Efforts to identify mutations that underlie inherited genetic diseases combined with strides in the development of gene therapy vectors over the last three decades have culminated in the approval of several adeno-associated virus (AAV)-based gene therapies. Genetic diseases that manifest in the lung such as cystic fibrosis (CF) and surfactant deficiencies, however, have so far proven to be elusive targets. Early clinical trials in CF using AAV serotype 2 (AAV2) achieved safety, but not efficacy endpoints; however, importantly, these studies provided critical information on barriers that need to be surmounted to translate AAV lung gene therapy toward clinical success. Bolstered with an improved understanding of AAV biology and more clinically relevant lung models, next-generation molecular biology and bioinformatics approaches have given rise to novel AAV capsid variants that offer improvements in transduction efficiency, immunological profile, and the ability to circumvent physical barriers in the lung such as mucus. This review discusses the principal limiting barriers to clinical success in lung gene therapy and focuses on novel engineered AAV capsid variants that have been developed to overcome those challenges.
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Affiliation(s)
- Ana Carneiro
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California, USA
| | - Hyuncheol Lee
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, California, USA
| | - Li Lin
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California, USA
| | - Joost van Haasteren
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, California, USA
| | - David V Schaffer
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California, USA.,California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, California, USA.,Department of Bioengineering, University of California, Berkeley, California, USA.,Department of Molecular and Cell Biology, University of California, Berkeley, California, USA.,Helen Wills Neuroscience Institute, University of California, Berkeley, California, USA.,Innovative Genomics Institute (IGI), University of California, Berkeley, California, USA
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31
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Wang Y, Zhou L, Tao R, Liu N, Long J, Qin F, Tang W, Yang Y, Chen Q, Yao S. sgBE: a structure-guided design of sgRNA architecture specifies base editing window and enables simultaneous conversion of cytosine and adenosine. Genome Biol 2020; 21:222. [PMID: 32859244 PMCID: PMC7453718 DOI: 10.1186/s13059-020-02137-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 08/07/2020] [Indexed: 02/05/2023] Open
Abstract
We present a base editing system, in which base editors are attached to different sites of sgRNA scaffold (sgBE). Each independent sgBE has its own specific editing pattern for a given target site. Among tested sgBEs, sgBE-SL4, in which deaminase is attached to the last stem-loop of sgRNA, yields the highest editing efficiency in the window several nucleotides next to the one edited by BE3. sgBE enables the simultaneous editing of adenine and cytosine. Finally, in order to facilitate in vivo base editing, we extend our sgBE system to an AAV-compatible Cas9, SaCas9 (Staphylococcus aureus), and observe robust base editing.
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Affiliation(s)
- Yanhong Wang
- Laboratory of Biotherapy, National Key Laboratory of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Renmin Nanlu 17, Chengdu, 610041, Sichuan, China
| | - Lifang Zhou
- Laboratory of Biotherapy, National Key Laboratory of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Renmin Nanlu 17, Chengdu, 610041, Sichuan, China
| | - Rui Tao
- Laboratory of Biotherapy, National Key Laboratory of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Renmin Nanlu 17, Chengdu, 610041, Sichuan, China
| | - Nan Liu
- Laboratory of Biotherapy, National Key Laboratory of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Renmin Nanlu 17, Chengdu, 610041, Sichuan, China
| | - Jie Long
- Laboratory of Biotherapy, National Key Laboratory of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Renmin Nanlu 17, Chengdu, 610041, Sichuan, China
| | - Fengming Qin
- Laboratory of Biotherapy, National Key Laboratory of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Renmin Nanlu 17, Chengdu, 610041, Sichuan, China
| | - Wenling Tang
- Laboratory of Biotherapy, National Key Laboratory of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Renmin Nanlu 17, Chengdu, 610041, Sichuan, China
| | - Yang Yang
- Laboratory of Biotherapy, National Key Laboratory of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Renmin Nanlu 17, Chengdu, 610041, Sichuan, China
| | - Qiang Chen
- Laboratory of Biotherapy, National Key Laboratory of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Renmin Nanlu 17, Chengdu, 610041, Sichuan, China
| | - Shaohua Yao
- Laboratory of Biotherapy, National Key Laboratory of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Renmin Nanlu 17, Chengdu, 610041, Sichuan, China.
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32
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Piras F, Kajaste-Rudnitski A. Antiviral immunity and nucleic acid sensing in haematopoietic stem cell gene engineering. Gene Ther 2020; 28:16-28. [PMID: 32661282 PMCID: PMC7357672 DOI: 10.1038/s41434-020-0175-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 07/06/2020] [Indexed: 02/06/2023]
Abstract
The low gene manipulation efficiency of human hematopoietic stem and progenitor cells (HSPC) remains a major hurdle for sustainable and broad clinical application of innovative therapies for a wide range of disorders. Given that all current and emerging gene transfer and editing technologies are bound to expose HSPC to exogenous nucleic acids and most often also to viral vectors, we reason that host antiviral factors and nucleic acid sensors play a pivotal role in the efficacy of HSPC genetic manipulation. Here, we review recent progress in our understanding of vector–host interactions and innate immunity in HSPC upon gene engineering and discuss how dissecting this crosstalk can guide the development of more stealth and efficient gene therapy approaches in the future.
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Affiliation(s)
- Francesco Piras
- San Raffaele Telethon Institute for Gene Therapy, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Anna Kajaste-Rudnitski
- San Raffaele Telethon Institute for Gene Therapy, IRCCS San Raffaele Scientific Institute, Milan, Italy.
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33
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Hsu HL, Brown A, Loveland AB, Lotun A, Xu M, Luo L, Xu G, Li J, Ren L, Su Q, Gessler DJ, Wei Y, Tai PWL, Korostelev AA, Gao G. Structural characterization of a novel human adeno-associated virus capsid with neurotropic properties. Nat Commun 2020; 11:3279. [PMID: 32606306 PMCID: PMC7327033 DOI: 10.1038/s41467-020-17047-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Accepted: 05/27/2020] [Indexed: 02/05/2023] Open
Abstract
Recombinant adeno-associated viruses (rAAVs) are currently considered the safest and most reliable gene delivery vehicles for human gene therapy. Three serotype capsids, AAV1, AAV2, and AAV9, have been approved for commercial use in patients, but they may not be suitable for all therapeutic contexts. Here, we describe a novel capsid identified in a human clinical sample by high-throughput, long-read sequencing. The capsid, which we have named AAVv66, shares high sequence similarity with AAV2. We demonstrate that compared to AAV2, AAVv66 exhibits enhanced production yields, virion stability, and CNS transduction. Unique structural properties of AAVv66 visualized by cryo-EM at 2.5-Å resolution, suggest that critical residues at the three-fold protrusion and at the interface of the five-fold axis of symmetry likely contribute to the beneficial characteristics of AAVv66. Our findings underscore the potential of AAVv66 as a gene therapy vector.
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Affiliation(s)
- Hung-Lun Hsu
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Alexander Brown
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Anna B Loveland
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Anoushka Lotun
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
| | - Meiyu Xu
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Li Luo
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, P. R., China
| | - Guangchao Xu
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, P. R., China
| | - Jia Li
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
| | - Lingzhi Ren
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
| | - Qin Su
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
- Viral Vector Core, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Dominic J Gessler
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Yuquan Wei
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, P. R., China
| | - Phillip W L Tai
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA.
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
| | - Andrei A Korostelev
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA.
| | - Guangping Gao
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA.
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
- Li Weibo Institute for Rare Diseases Research, University of Massachusetts Medical School, Worcester, MA, USA.
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Ran G, Chen X, Xie Y, Zheng Q, Xie J, Yu C, Pittman N, Qi S, Yu FX, Agbandje-McKenna M, Srivastava A, Ling C. Site-Directed Mutagenesis Improves the Transduction Efficiency of Capsid Library-Derived Recombinant AAV Vectors. Mol Ther Methods Clin Dev 2020; 17:545-555. [PMID: 32258217 PMCID: PMC7114622 DOI: 10.1016/j.omtm.2020.03.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 03/09/2020] [Accepted: 03/10/2020] [Indexed: 12/26/2022]
Abstract
Recombinant adeno-associated virus (rAAV) vectors selected from capsid libraries present enormous advantages in high selectivity of tissue tropism and their potential use in human gene therapy applications. For example, rAAV-LK03, was used in a gene therapy trial for hemophilia A (ClinicalTrials.gov: NCT03003533). However, high doses in patients resulted in severe adverse events and subsequent loss of factor VIII (FVIII) expression. Thus, additional strategies are needed to enhance the transduction efficiency of capsid library-derived rAAV vectors such that improved clinical efficacy can be achieved at low vector doses. In this study, we characterized two commonly used library-derived rAAV vectors, rAAV-DJ and rAAV-LK03. It was concluded that rAAV-DJ shared similar transport pathways (e.g., cell surface binding, endocytosis-dependent internalization, and cytoplasmic trafficking) with rAAV serotype 2, while rAAV-LK03 and rAAV serotype 3 shared similar transport pathways. We then performed site-directed mutagenesis of surface-exposed tyrosine (Y), serine (S), aspartic acid (D), and tryptophan (W) residues on rAAV-DJ and rAAV-LK03 capsids. Our results demonstrated that rAAV-DJ-S269T and rAAV-LK03-Y705+731F variants had significantly enhanced transduction efficiency compared to wild-type counterparts. Our studies suggest that the strategy of site-directed mutagenesis should be applicable to other non-natural AAV variants for their optimal use in human gene therapy.
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Affiliation(s)
- Gai Ran
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai 200438, China
| | - Xiao Chen
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai 200438, China
| | - Yilin Xie
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai 200438, China
| | - Qingyun Zheng
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai 200438, China
| | - Jinyan Xie
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai 200438, China
| | - Chenghui Yu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai 200438, China
| | - Nikea Pittman
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, FL 32611, USA
- Powell Gene Therapy Center, University of Florida College of Medicine, Gainesville, FL 32611, USA
| | - Sixian Qi
- Institute of Pediatrics, Children’s Hospital of Fudan University, Shanghai 201102, China
| | - Fa-Xing Yu
- Institute of Pediatrics, Children’s Hospital of Fudan University, Shanghai 201102, China
- Shanghai Key Laboratory of Medical Epigenetics, Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Mavis Agbandje-McKenna
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, FL 32611, USA
- Powell Gene Therapy Center, University of Florida College of Medicine, Gainesville, FL 32611, USA
- Genetics Institute, University of Florida College of Medicine, Gainesville, FL 32611, USA
| | - Arun Srivastava
- Powell Gene Therapy Center, University of Florida College of Medicine, Gainesville, FL 32611, USA
- Genetics Institute, University of Florida College of Medicine, Gainesville, FL 32611, USA
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida College of Medicine, Gainesville, FL 32611, USA
- Department of Molecular Genetics and Microbiology
- Shands Cancer Center, University of Florida College of Medicine, Gainesville, FL 32611, USA
| | - Chen Ling
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai 200438, China
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida College of Medicine, Gainesville, FL 32611, USA
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Zengel J, Carette JE. Structural and cellular biology of adeno-associated virus attachment and entry. Adv Virus Res 2020; 106:39-84. [PMID: 32327148 DOI: 10.1016/bs.aivir.2020.01.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Adeno-associated virus (AAV) is a nonenveloped, ssDNA virus in the parvovirus family, which has become one of the leading candidate vectors for human gene therapy. AAV has been studied extensively to identify host cellular factors involved in infection, as well as to identify capsid variants that confer clinically favorable transduction profiles ex vivo and in vivo. Recent advances in technology have allowed for direct genetic approaches to be used to more comprehensively characterize host factors required for AAV infection and allowed for identification of a critical multi-serotype receptor, adeno-associated virus receptor (AAVR). In this chapter, we will discuss the interactions of AAV with its glycan and proteinaceous receptors and describe the host and viral components involved in AAV entry, which requires cellular attachment, endocytosis, trafficking to the trans-Golgi network and nuclear import. AAV serves as a paradigm for entry of nonenveloped viruses. Furthermore, we will discuss the potential of utilizing our increased understanding of virus-host interactions during AAV entry to develop better AAV-based therapeutics, with a focus on host factors and capsid interactions involved in in vivo tropism.
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Structure comparison of the chimeric AAV2.7m8 vector with parental AAV2. J Struct Biol 2019; 209:107433. [PMID: 31859208 DOI: 10.1016/j.jsb.2019.107433] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 11/28/2019] [Accepted: 12/03/2019] [Indexed: 12/26/2022]
Abstract
The AAV2.7m8 vector is an engineered capsid with a 10-amino acid insertion in adeno-associated virus (AAV) surface variable region VIII (VR-VIII) resulting in the alteration of an antigenic region of AAV2 and the ability to efficiently transduce retina cells following intravitreal administration. Directed evolution and in vivo screening in the mouse retina isolated this vector. In the present study, we sought to identify the structural differences between a recombinant AAV2.7m8 (rAAV2.7m8) vector packaging a GFP genome and its parental serotype, AAV2, by cryo-electron microscopy (cryo-EM) and image reconstruction. The structures of rAAV2.7m8 and AAV2 were determined to 2.91 and 3.02 Å resolution, respectively. The rAAV2.7m8 amino acid side-chains for residues 219-745 (the last C-terminal residue) were interpretable in the density map with the exception of the 10 inserted amino acids. While observable in a low sigma threshold density, side-chains were only resolved at the base of the insertion, likely due to flexibility at the top of the loop. A comparison to parental AAV2 (ordered from residues 217-735) showed the structures to be similar, except at some side-chains that had different orientations and, in VR-VIII containing the 10 amino acid insertion. VR-VIII is part of an AAV2 antigenic epitope, and the difference is consistent with rAAV2.7m8's escape from a known AAV2 monoclonal antibody, C37-B. The observations provide valuable insight into the configuration of inserted surface peptides on the AAV capsid and structural differences to be leveraged for future AAV vector rational design, especially for retargeted tropism and antibody escape.
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Madigan VJ, Yuziuk JA, Chiarella AM, Tyson TO, Meganck RM, Elmore ZC, Tse LV, Hathaway NA, Asokan A. Ring finger protein 121 is a potent regulator of adeno-associated viral genome transcription. PLoS Pathog 2019; 15:e1007988. [PMID: 31386698 PMCID: PMC6697353 DOI: 10.1371/journal.ppat.1007988] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 08/16/2019] [Accepted: 07/17/2019] [Indexed: 12/12/2022] Open
Abstract
Adeno-associated viruses (AAV) are Dependoparvoviruses that have shown promise as recombinant vectors for gene therapy. While infectious pathways of AAV are well studied, gaps remain in our understanding of host factors affecting vector genome expression. Here, we map the role of ring finger protein 121 (RNF121), an E3 ubiquitin ligase, as a key regulator of AAV genome transcription. CRISPR-mediated knockout of RNF121 (RNF121 KO) in different cells markedly decreased AAV transduction regardless of capsid serotype or vector dose. Recombinant AAV transduction is partially rescued by overexpressing RNF121, but not by co-infection with helper Adenovirus. Major steps in the AAV infectious pathway including cell surface binding, cellular uptake, nuclear entry, capsid uncoating and second strand synthesis are unaffected. While gene expression from transfected plasmids or AAV genomes is unaffected, mRNA synthesis from AAV capsid-associated genomes is markedly decreased in RNF121 KO cells. These observations were attributed to transcriptional arrest as corroborated by RNAPol-ChIP and mRNA half-life measurements. Although AAV capsid proteins do not appear to be direct substrates of RNF121, the catalytic domain of the E3 ligase appears essential. Inhibition of ubiquitin-proteasome pathways revealed that blocking Valosin Containing Protein (VCP/p97), which targets substrates to the proteasome, can selectively and completely restore AAV-mediated transgene expression in RNF121 KO cells. Expanding on this finding, transcriptomic and proteomic analysis revealed that the catalytic subunit of DNA PK (DNAPK-Cs), a known activator of VCP, is upregulated in RNF121 KO cells and that the DNA damage machinery is enriched at sites of stalled AAV genome transcription. We postulate that a network of RNF121, VCP and DNA damage response elements function together to regulate transcriptional silencing and/or activation of AAV vector genomes. Recombinant AAV vectors are at the forefront of clinical gene therapy. There is a need to better understand the mechanisms dictating AAV transduction in the host. Here, we identify a network of host proteins involving RNF121, p97 and the DNA damage machinery as potent factors regulating AAV genome transcription. Our study sheds light on an understudied aspect of AAV biology with implications for gene therapy.
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Affiliation(s)
- Victoria J. Madigan
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States of America
- Gene Therapy Center, the University of North Carolina at Chapel Hill, Chapel Hill, NC, United States of America
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States of America
| | - Julianne A. Yuziuk
- Gene Therapy Center, the University of North Carolina at Chapel Hill, Chapel Hill, NC, United States of America
| | - Anna M. Chiarella
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States of America
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Chapel Hill, NC, United States of America
| | - Tyne O. Tyson
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States of America
| | - Rita M. Meganck
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States of America
- Gene Therapy Center, the University of North Carolina at Chapel Hill, Chapel Hill, NC, United States of America
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States of America
| | - Zachary C. Elmore
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States of America
- Department of Molecular Genetics & Microbiology, Duke University School of Medicine, Durham, NC, United States of America
| | - Longping V. Tse
- Gene Therapy Center, the University of North Carolina at Chapel Hill, Chapel Hill, NC, United States of America
| | - Nathaniel A. Hathaway
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Chapel Hill, NC, United States of America
| | - Aravind Asokan
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States of America
- Department of Molecular Genetics & Microbiology, Duke University School of Medicine, Durham, NC, United States of America
- * E-mail:
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Fakhiri J, Schneider MA, Puschhof J, Stanifer M, Schildgen V, Holderbach S, Voss Y, El Andari J, Schildgen O, Boulant S, Meister M, Clevers H, Yan Z, Qiu J, Grimm D. Novel Chimeric Gene Therapy Vectors Based on Adeno-Associated Virus and Four Different Mammalian Bocaviruses. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2019; 12:202-222. [PMID: 30766894 PMCID: PMC6360332 DOI: 10.1016/j.omtm.2019.01.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 01/11/2019] [Indexed: 02/06/2023]
Abstract
Parvoviruses are highly attractive templates for the engineering of safe, efficient, and specific gene therapy vectors, as best exemplified by adeno-associated virus (AAV). Another candidate that currently garners increasing attention is human bocavirus 1 (HBoV1). Notably, HBoV1 capsids can cross-package recombinant (r)AAV2 genomes, yielding rAAV2/HBoV1 chimeras that specifically transduce polarized human airway epithelia (pHAEs). Here, we largely expanded the repertoire of rAAV/BoV chimeras, by assembling packaging plasmids encoding the capsid genes of four additional primate bocaviruses, HBoV2–4 and GBoV (Gorilla BoV). Capsid protein expression and efficient rAAV cross-packaging were validated by immunoblotting and qPCR, respectively. Interestingly, not only HBoV1 but also HBoV4 and GBoV transduced pHAEs as well as primary human lung organoids. Flow cytometry analysis of pHAEs revealed distinct cellular specificities between the BoV isolates, with HBoV1 targeting ciliated, club, and KRT5+ basal cells, whereas HBoV4 showed a preference for KRT5+ basal cells. Surprisingly, primary human hepatocytes, skeletal muscle cells, and T cells were also highly amenable to rAAV/BoV transduction. Finally, we adapted our pipeline for AAV capsid gene shuffling to all five BoV isolates. Collectively, our chimeric rAAV/BoV vectors and bocaviral capsid library represent valuable new resources to dissect BoV biology and to breed unique gene therapy vectors.
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Affiliation(s)
- Julia Fakhiri
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Heidelberg, Germany.,BioQuant Center, University of Heidelberg, Heidelberg, Germany
| | - Marc A Schneider
- Translational Research Unit, Thoraxklinik at Heidelberg University Hospital, Heidelberg, Germany.,German Center for Lung Research (DZL), Translational Lung Research Center Heidelberg (TLRC), Heidelberg, Germany
| | - Jens Puschhof
- Hubrecht Institute and Oncode Institute, Royal Netherlands Academy of Arts and Sciences (KNAW), Utrecht, the Netherlands
| | - Megan Stanifer
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Heidelberg, Germany.,Research Group "Cellular Polarity of Viral Infection", German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Verena Schildgen
- Institute for Pathology, Kliniken der Stadt Köln gGmbH, Hospital of the Private University Witten/Herdecke, Cologne, Germany
| | - Stefan Holderbach
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Heidelberg, Germany.,BioQuant Center, University of Heidelberg, Heidelberg, Germany
| | - Yannik Voss
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Heidelberg, Germany.,BioQuant Center, University of Heidelberg, Heidelberg, Germany
| | - Jihad El Andari
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Heidelberg, Germany.,BioQuant Center, University of Heidelberg, Heidelberg, Germany
| | - Oliver Schildgen
- Institute for Pathology, Kliniken der Stadt Köln gGmbH, Hospital of the Private University Witten/Herdecke, Cologne, Germany
| | - Steeve Boulant
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Heidelberg, Germany.,Research Group "Cellular Polarity of Viral Infection", German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Michael Meister
- Translational Research Unit, Thoraxklinik at Heidelberg University Hospital, Heidelberg, Germany.,German Center for Lung Research (DZL), Translational Lung Research Center Heidelberg (TLRC), Heidelberg, Germany
| | - Hans Clevers
- Hubrecht Institute and Oncode Institute, Royal Netherlands Academy of Arts and Sciences (KNAW), Utrecht, the Netherlands.,University Medical Center (UMC) Utrecht, Utrecht, the Netherlands.,Princess Máxima Centre, Utrecht, the Netherlands
| | - Ziying Yan
- Department of Anatomy and Cell Biology, Center for Gene Therapy, The University of Iowa, Iowa City, IA, USA
| | - Jianming Qiu
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Dirk Grimm
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Heidelberg, Germany.,BioQuant Center, University of Heidelberg, Heidelberg, Germany.,German Center for Infection Research (DZIF), partner site Heidelberg, Heidelberg, Germany
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Lopes-Pacheco M, Kitoko JZ, Morales MM, Petrs-Silva H, Rocco PRM. Self-complementary and tyrosine-mutant rAAV vectors enhance transduction in cystic fibrosis bronchial epithelial cells. Exp Cell Res 2018; 372:99-107. [PMID: 30244179 DOI: 10.1016/j.yexcr.2018.09.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 09/13/2018] [Accepted: 09/20/2018] [Indexed: 10/28/2022]
Abstract
Recombinant adeno-associated virus (rAAV) vector platforms have shown considerable therapeutic success in gene therapy for inherited disorders. In cystic fibrosis (CF), administration of first-generation rAAV2 was safe, but clinical benefits were not clearly demonstrated. Therefore, next-generation vectors that overcome rate-limiting steps in rAAV transduction are needed to obtain successful gene therapy for this devastating disease. In this study, we evaluated the effects of single-strand or self-complementary (sc) rAAV vectors containing single or multiple tyrosine-to-phenylalanine (Y-F) mutations in capsid surface-exposed residues on serotypes 2, 8 or 9. For this purpose, CF bronchial epithelial (CFBE) cells were transduced with rAAV vectors, and the transgene expression of enhanced green fluorescence protein (eGFP) was analyzed at different time points. The effects of vectors on the cell viability, host cell cycle and in association with co-adjuvant drugs that modulate intracellular vector trafficking were also investigated. Six rAAV vectors demonstrated greater percentage of eGFP+ cells compared to their counterparts at days 4, 7 and 10 post-transduction: rAAV2 Y(272,444,500,730)F, with 1.95-, 3.5- and 3.06-fold increases; rAAV2 Y(252,272,444,500,704,730)F, with 1.65-, 2.12-, and 2-fold increases; scrAAV2 WT, with 1.69-, 2.68-, and 2.32-fold increases; scrAAV8 Y773F, with 57-, 6.06-, and 7-fold increases; scrAAV9 WT, with 7.47-, 4.64-, and 3.66-fold increases; and scrAAV9 Y446F, with 8.39-, 4.62-, and 4.4-fold increases. At days 15, 20, and 30 post-transduction, these vectors still demonstrated higher transgene expression than transfected cells. Although the percentage of eGFP+ cells reduced during the time-course analysis, the delta mean fluorescence intensity increased. These vectors also led to increased percentage of cells in G1-phase without eliciting any cytotoxicity. Prior administration of bortezomib or genistein did not increase eGFP expression in cells transduced with either rAAV2 Y(272,444,500,730)F or rAAV2 Y(252,272,444,500,704,730)F. In conclusion, self-complementary and tyrosine capsid mutations on rAAV serotypes 2, 8, and 9 led to more efficient transduction than their counterparts in CFBE cells by overcoming the intracellular trafficking and second-strand DNA synthesis limitations.
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Affiliation(s)
- Miquéias Lopes-Pacheco
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Laboratory of Cellular and Molecular Physiology, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Jamil Z Kitoko
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Laboratory of Cellular and Molecular Physiology, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcelo M Morales
- Laboratory of Cellular and Molecular Physiology, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Hilda Petrs-Silva
- Laboratory of Neurogenesis, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Patricia R M Rocco
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
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Aktas Z, Rao H, Slauson SR, Gabelt BT, Larsen IV, Sheridan RTC, Herrnberger L, Tamm ER, Kaufman PL, Brandt CR. Proteasome Inhibition Increases the Efficiency of Lentiviral Vector-Mediated Transduction of Trabecular Meshwork. Invest Ophthalmol Vis Sci 2018; 59:298-310. [PMID: 29340644 PMCID: PMC5961099 DOI: 10.1167/iovs.17-22074] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Purpose To determine if proteasome inhibition using MG132 increased the efficiency of FIV vector–mediated transduction in human trabecular meshwork (TM)-1 cells and monkey organ-cultured anterior segments (MOCAS). Methods TM-1 cells were pretreated for 1 hour with 0.5% dimethyl sulfoxide (DMSO; vehicle control) or 5 to 50 μM MG132 and transduced with FIV.GFP (green fluorescent protein)– or FIV.mCherry-expressing vector at a multiplicity of transduction (MOT) of 20. At 24 hours, cells were fixed and stained with antibodies for GFP, and positive cells were counted, manually or by fluorescence-activated cell sorting (FACS). Cells transduced with FIV.GFP particles alone were used as controls. The effect of 20 μM MG132 treatment on high- and low-dose (2 × 107 and 0.8 × 107 transducing units [TU], respectively) FIV.GFP transduction with or without MG132 was also evaluated in MOCAS using fluorescence microscopy. Vector genome equivalents in cells and tissues were quantified by quantitative (q)PCR on DNA. Results In the MG132 treatment groups, there was a significant dose-dependent increase in the percentage of transduced cells at all concentrations tested. Vector genome equivalents were also increased in TM-1 cells treated with MG132. Increased FIV.GFP expression in the TM was also observed in MOCAS treated with 20 μM MG132 and the high dose of vector. Vector genome equivalents were also significantly increased in the MOCAS tissues. Increased transduction was not seen with the low dose of virus. Conclusions Proteasome inhibition increased the transduction efficiency of FIV particles in TM-1 cells and MOCAS and may be a useful adjunct for delivery of therapeutic genes to the TM by lentiviral vectors.
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Affiliation(s)
- Zeynep Aktas
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States.,Department of Ophthalmology, Gazi University Medical Faculty, Ankara, Turkey
| | - Hongyu Rao
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Sarah R Slauson
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - B'Ann T Gabelt
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Inna V Larsen
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Rachael T C Sheridan
- UW Carbone Cancer Center Flow Cytometry Laboratory, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Leonie Herrnberger
- Institute of Human Anatomy, University of Regensburg, Regensburg, Germany
| | - Ernst R Tamm
- Institute of Human Anatomy, University of Regensburg, Regensburg, Germany
| | - Paul L Kaufman
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States.,McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Curtis R Brandt
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States.,McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, Wisconsin, United States.,Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, United States
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41
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Brown N, Song L, Kollu NR, Hirsch ML. Adeno-Associated Virus Vectors and Stem Cells: Friends or Foes? Hum Gene Ther 2018; 28:450-463. [PMID: 28490211 DOI: 10.1089/hum.2017.038] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The infusion of healthy stem cells into a patient-termed "stem-cell therapy"-has shown great promise for the treatment of genetic and non-genetic diseases, including mucopolysaccharidosis type 1, Parkinson's disease, multiple sclerosis, numerous immunodeficiency disorders, and aplastic anemia. Stem cells for cell therapy can be collected from the patient (autologous) or collected from another "healthy" individual (allogeneic). The use of allogenic stem cells is accompanied with the potentially fatal risk that the transplanted donor T cells will reject the patient's cells-a process termed "graft-versus-host disease." Therefore, the use of autologous stem cells is preferred, at least from the immunological perspective. However, an obvious drawback is that inherently as "self," they contain the disease mutation. As such, autologous cells for use in cell therapies often require genetic "correction" (i.e., gene addition or editing) prior to cell infusion and therefore the requirement for some form of nucleic acid delivery, which sets the stage for the AAV controversy discussed herein. Despite being the most clinically applied gene delivery context to date, unlike other more concerning integrating and non-integrating vectors such as retroviruses and adenovirus, those based on adeno-associated virus (AAV) have not been employed in the clinic. Furthermore, published data regarding AAV vector transduction of stem cells are inconsistent in regards to vector transduction efficiency, while the pendulum swings far in the other direction with demonstrations of AAV vector-induced toxicity in undifferentiated cells. The variation present in the literature examining the transduction efficiency of AAV vectors in stem cells may be due to numerous factors, including inconsistencies in stem-cell collection, cell culture, vector preparation, and/or transduction conditions. This review summarizes the controversy surrounding AAV vector transduction of stem cells, hopefully setting the stage for future elucidation and eventual therapeutic applications.
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Affiliation(s)
- Nolan Brown
- 1 Gene Therapy Center, University of North Carolina at Chapel Hill , North Carolina.,2 Department of Ophthalmology, University of North Carolina at Chapel Hill , North Carolina
| | - Liujiang Song
- 1 Gene Therapy Center, University of North Carolina at Chapel Hill , North Carolina.,2 Department of Ophthalmology, University of North Carolina at Chapel Hill , North Carolina
| | - Nageswara R Kollu
- 1 Gene Therapy Center, University of North Carolina at Chapel Hill , North Carolina.,2 Department of Ophthalmology, University of North Carolina at Chapel Hill , North Carolina
| | - Matthew L Hirsch
- 1 Gene Therapy Center, University of North Carolina at Chapel Hill , North Carolina.,2 Department of Ophthalmology, University of North Carolina at Chapel Hill , North Carolina
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A novel and highly efficient AAV6 mutant. Virus Genes 2017; 54:165-171. [PMID: 29282655 DOI: 10.1007/s11262-017-1531-2] [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: 09/09/2017] [Accepted: 12/19/2017] [Indexed: 10/18/2022]
Abstract
Adeno-associated virus has been gaining prominence in its use as a highly secure virus gene vector with low immunogenicity in the field of human gene therapy. However, wild-type adeno-associated virus sometimes has low transduction efficiency for certain tissues or cells both in vivo and in vitro. Thus, achieving the desired level of expression often requires a large dose. Large doses of viral injection in clinical applications will not only trigger the body's immune response but will come at a high production cost. To improve the transduction efficiency of adeno-associated virus 6 (AAV6), we herein used fusion PCR to mutate a specific amino acid of the VP2 region of the wild-type AAV6 (AAV6-WT) and obtained AAV6-S663L, AAV6Y705 + 731F + T492A, AAV6Y705 + 731F + T492 V + S663 V and so on. We concluded that AAV6-S663L was the most efficient AAV6 mutant. When HEK293 cells were infected in vitro with a virus at a multiplicity of infection value of 1000, the transduction rate of AAV6-WT was only 43.8%, while that of AAV6-S663L was 83.9%. This highly efficient AAV6 mutant is highly significant for the future use of AAV6 in gene therapy.
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43
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de la Puente P, Luderer MJ, Federico C, Jin A, Gilson RC, Egbulefu C, Alhallak K, Shah S, Muz B, Sun J, King J, Kohnen D, Salama NN, Achilefu S, Vij R, Azab AK. Enhancing proteasome-inhibitory activity and specificity of bortezomib by CD38 targeted nanoparticles in multiple myeloma. J Control Release 2017; 270:158-176. [PMID: 29196043 DOI: 10.1016/j.jconrel.2017.11.045] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 10/29/2017] [Accepted: 11/27/2017] [Indexed: 01/03/2023]
Abstract
The establishment of more effective treatments that can circumvent chemoresistance in Multiple Myeloma (MM) is a priority. Although bortezomib (BTZ) is one of the most potent proteasome inhibitors available, still possesses limitations related to dose limiting side effects. Several strategies have been developed to improve the delivery of chemotherapies to MM by targeting different moieties expressed on MM cells to nanoparticle delivery systems (NPs), which have failed mainly due to their heterogeneous expression on these cells. Our goal was to test CD38 targeted chitosan NPs as novel targeting moiety for MM to improve the potency and efficacy of BTZ in MM cells and reduce the side effects in healthy tissue. We have showed preferential BTZ release in tumor-microenvironment, specific binding to MM cells, and an improved drug cellular uptake through BTZ diffusion from the surface and endocytosed NPs, which translated in enhanced proteasome inhibition and robust cytotoxic effect on MM cells when BTZ was administered through anti-CD38 chitosan NPs. Furthermore, the anti-CD38 chitosan NPs specifically delivered therapeutic agents to MM cells improving therapeutic efficacy and reducing side effects in vivo. The anti-CD38 chitosan NPs showed low toxicity profile allowing enhancement of proteasome-inhibitory activity and specificity of BTZ by endocytosis-mediated uptake of CD38 representing a promising therapy in MM.
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Affiliation(s)
- Pilar de la Puente
- Department of Radiation Oncology, Washington University in Saint Louis School of Medicine, MO, USA
| | - Micah J Luderer
- Department of Radiation Oncology, Washington University in Saint Louis School of Medicine, MO, USA
| | - Cinzia Federico
- Department of Radiation Oncology, Washington University in Saint Louis School of Medicine, MO, USA
| | - Abbey Jin
- Department of Radiation Oncology, Washington University in Saint Louis School of Medicine, MO, USA; Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, MO, USA
| | - Rebecca C Gilson
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, MO, USA
| | - Christopher Egbulefu
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, MO, USA
| | - Kinan Alhallak
- Department of Radiation Oncology, Washington University in Saint Louis School of Medicine, MO, USA
| | - Shruti Shah
- Department of Radiation Oncology, Washington University in Saint Louis School of Medicine, MO, USA
| | - Barbara Muz
- Department of Radiation Oncology, Washington University in Saint Louis School of Medicine, MO, USA
| | - Jennifer Sun
- Department of Radiation Oncology, Washington University in Saint Louis School of Medicine, MO, USA
| | - Justin King
- Section of Stem Cell Transplant and Leukemia, Division of Medical Oncology, USA
| | - Daniel Kohnen
- Section of Stem Cell Transplant and Leukemia, Division of Medical Oncology, USA
| | - Noha Nabil Salama
- Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, MO, USA; Department of Pharmaceutics and Industrial Pharmacy, Cairo University Faculty of Pharmacy, Cairo, Egypt
| | - Samuel Achilefu
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, MO, USA
| | - Ravi Vij
- Section of Stem Cell Transplant and Leukemia, Division of Medical Oncology, USA
| | - Abdel Kareem Azab
- Department of Radiation Oncology, Washington University in Saint Louis School of Medicine, MO, USA.
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Grosse S, Penaud-Budloo M, Herrmann AK, Börner K, Fakhiri J, Laketa V, Krämer C, Wiedtke E, Gunkel M, Ménard L, Ayuso E, Grimm D. Relevance of Assembly-Activating Protein for Adeno-associated Virus Vector Production and Capsid Protein Stability in Mammalian and Insect Cells. J Virol 2017; 91:e01198-17. [PMID: 28768875 PMCID: PMC5625497 DOI: 10.1128/jvi.01198-17] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 07/28/2017] [Indexed: 12/16/2022] Open
Abstract
The discovery that adeno-associated virus 2 (AAV2) encodes an eighth protein, called assembly-activating protein (AAP), transformed our understanding of wild-type AAV biology. Concurrently, it raised questions about the role of AAP during production of recombinant vectors based on natural or molecularly engineered AAV capsids. Here, we show that AAP is indeed essential for generation of functional recombinant AAV2 vectors in both mammalian and insect cell-based vector production systems. Surprisingly, we observed that AAV2 capsid proteins VP1 to -3 are unstable in the absence of AAP2, likely due to rapid proteasomal degradation. Inhibition of the proteasome led to an increase of intracellular VP1 to -3 but neither triggered assembly of functional capsids nor promoted nuclear localization of the capsid proteins. Together, this underscores the crucial and unique role of AAP in the AAV life cycle, where it rapidly chaperones capsid assembly, thus preventing degradation of free capsid proteins. An expanded analysis comprising nine alternative AAV serotypes (1, 3 to 9, and rh10) showed that vector production always depends on the presence of AAP, with the exceptions of AAV4 and AAV5, which exhibited AAP-independent, albeit low-level, particle assembly. Interestingly, AAPs from all 10 serotypes could cross-complement AAP-depleted helper plasmids during vector production, despite there being distinct intracellular AAP localization patterns. These were most pronounced for AAP4 and AAP5, congruent with their inability to rescue an AAV2/AAP2 knockout. We conclude that AAP is key for assembly of genuine capsids from at least 10 different AAV serotypes, which has implications for vectors derived from wild-type or synthetic AAV capsids.IMPORTANCE Assembly of adeno-associated virus 2 (AAV2) is regulated by the assembly-activating protein (AAP), whose open reading frame overlaps with that of the viral capsid proteins. As the majority of evidence was obtained using virus-like particles composed solely of the major capsid protein VP3, AAP's role in and relevance for assembly of genuine AAV capsids have remained largely unclear. Thus, we established a trans-complementation assay permitting assessment of AAP functionality during production of recombinant vectors based on complete AAV capsids and derived from any serotype. We find that AAP is indeed a critical factor not only for AAV2, but also for generation of vectors derived from nine other AAV serotypes. Moreover, we identify a new role of AAP in maintaining capsid protein stability in mammalian and insect cells. Thereby, our study expands our current understanding of AAV/AAP biology, and it concomitantly provides insights into the importance of AAP for AAV vector production.
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Affiliation(s)
- Stefanie Grosse
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Cluster of Excellence CellNetworks, Heidelberg, Germany
- BioQuant Center, University of Heidelberg, Heidelberg, Germany
| | - Magalie Penaud-Budloo
- INSERM UMR1089, University of Nantes, Centre Hospitalier Universitaire, Nantes, France
| | - Anne-Kathrin Herrmann
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Cluster of Excellence CellNetworks, Heidelberg, Germany
- BioQuant Center, University of Heidelberg, Heidelberg, Germany
| | - Kathleen Börner
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Cluster of Excellence CellNetworks, Heidelberg, Germany
- BioQuant Center, University of Heidelberg, Heidelberg, Germany
- German Center for Infection Research, Partner Site Heidelberg, Heidelberg, Germany
| | - Julia Fakhiri
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Cluster of Excellence CellNetworks, Heidelberg, Germany
- BioQuant Center, University of Heidelberg, Heidelberg, Germany
| | - Vibor Laketa
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Cluster of Excellence CellNetworks, Heidelberg, Germany
- German Center for Infection Research, Partner Site Heidelberg, Heidelberg, Germany
| | - Chiara Krämer
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Cluster of Excellence CellNetworks, Heidelberg, Germany
- BioQuant Center, University of Heidelberg, Heidelberg, Germany
| | - Ellen Wiedtke
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Cluster of Excellence CellNetworks, Heidelberg, Germany
- BioQuant Center, University of Heidelberg, Heidelberg, Germany
| | - Manuel Gunkel
- BioQuant Center, University of Heidelberg, Heidelberg, Germany
- CellNetworks Advanced Biological Screening Facility, University of Heidelberg, Heidelberg, Germany
| | - Lucie Ménard
- INSERM UMR1089, University of Nantes, Centre Hospitalier Universitaire, Nantes, France
| | - Eduard Ayuso
- INSERM UMR1089, University of Nantes, Centre Hospitalier Universitaire, Nantes, France
| | - Dirk Grimm
- Department of Infectious Diseases/Virology, Heidelberg University Hospital, Cluster of Excellence CellNetworks, Heidelberg, Germany
- BioQuant Center, University of Heidelberg, Heidelberg, Germany
- German Center for Infection Research, Partner Site Heidelberg, Heidelberg, Germany
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45
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Mingozzi F, High KA. Overcoming the Host Immune Response to Adeno-Associated Virus Gene Delivery Vectors: The Race Between Clearance, Tolerance, Neutralization, and Escape. Annu Rev Virol 2017; 4:511-534. [PMID: 28961410 DOI: 10.1146/annurev-virology-101416-041936] [Citation(s) in RCA: 132] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Immune responses in gene therapy with adeno-associated virus (AAV) vectors have been the object of almost two decades of study. Although preclinical models helped to define and predict certain aspects of interactions between the vector and the host immune system, most of our current knowledge has come from clinical trials. These studies have allowed development of effective interventions for modulating immunotoxicities associated with vector administration, resulting in therapeutic advances. However, the road to full understanding and effective modulation of immune responses in gene therapy is still long; the determinants of the balance between tolerance and immunogenicity in AAV vector-mediated gene transfer are not fully understood, and effective solutions for overcoming preexisting neutralizing antibodies are still lacking. However, despite these challenges, the goal of reliably delivering effective gene-based treatments is now in sight.
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Affiliation(s)
- Federico Mingozzi
- Genethon and INSERM U951, 91000 Evry, France; .,University Pierre and Marie Curie Paris 6 and INSERM U974, 75651 Paris, France
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46
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TFEB-mediated activation of the lysosome-autophagy system affects the transduction efficiency of adeno-associated virus 2. Virology 2017; 510:1-8. [PMID: 28688268 DOI: 10.1016/j.virol.2017.06.030] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 06/19/2017] [Accepted: 06/26/2017] [Indexed: 11/22/2022]
Abstract
Adeno-associated virus (AAV)-mediated gene transfer is an appealing therapeutic option due to AAV's safety profile. Effective delivery of AAV's genetic cargo to the nucleus, however, requires evasion of host cell barriers, including cellular clearance mechanisms mediated by the lysosome-autophagy system. We used AAV serotype 2 to monitor the autophagic response to cellular internalization of AAV and to characterize the effect of AAV-induced activation of autophagy on transgene expression. We found AAV2 internalization to induce activation of transcription factor EB, a master regulator of autophagy and lysosomal biogenesis, and upregulation of the lysosome-autophagy system. We showed that AAV2-induced activation of autophagy parallels a reduction in transgene expression, but also an increase in autophagic clearance of protein aggregates. These results can inform the design of AAV vectors with autophagy-modulating properties for applications ranging from the design of efficient gene delivery vectors to the treatment of diseases characterized by accumulation of autophagic cargo.
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47
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Flatt JW, Greber UF. Viral mechanisms for docking and delivering at nuclear pore complexes. Semin Cell Dev Biol 2017; 68:59-71. [PMID: 28506891 DOI: 10.1016/j.semcdb.2017.05.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 05/11/2017] [Indexed: 12/22/2022]
Abstract
Some viruses possess the remarkable ability to transport their genomes across nuclear pore complexes (NPCs) for replication inside the host cell's intact nuclear compartment. Viral mechanisms for crossing the restrictive NPC passageway are highly complex and astonishingly diverse, requiring in each case stepwise interaction between incoming virus particles and components of the nuclear transport machinery. Exactly how a large viral genome loaded with accessory proteins is able to pass through the relatively narrow central channel of the NPC without causing catastrophic structural damage is not yet fully understood. It appears likely, however, that the overall structure of the NPC changes in response to the cargo. Translocation may result in nucleic acids being misdelivered to the cytoplasm. Here we consider in detail the diverse strategies that viruses have evolved to target and subvert NPCs during infection. For decades, this process has both captivated and confounded researchers in the fields of virology, cell biology, and structural biology.
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Affiliation(s)
- Justin W Flatt
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Urs F Greber
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
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48
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Kothari P, De BP, He B, Chen A, Chiuchiolo MJ, Kim D, Nikolopoulou A, Amor-Coarasa A, Dyke JP, Voss HU, Kaminsky SM, Foley CP, Vallabhajosula S, Hu B, DiMagno SG, Sondhi D, Crystal RG, Babich JW, Ballon D. Radioiodinated Capsids Facilitate In Vivo Non-Invasive Tracking of Adeno-Associated Gene Transfer Vectors. Sci Rep 2017; 7:39594. [PMID: 28059103 PMCID: PMC5216390 DOI: 10.1038/srep39594] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 11/24/2016] [Indexed: 01/07/2023] Open
Abstract
Viral vector mediated gene therapy has become commonplace in clinical trials for a wide range of inherited disorders. Successful gene transfer depends on a number of factors, of which tissue tropism is among the most important. To date, definitive mapping of the spatial and temporal distribution of viral vectors in vivo has generally required postmortem examination of tissue. Here we present two methods for radiolabeling adeno-associated virus (AAV), one of the most commonly used viral vectors for gene therapy trials, and demonstrate their potential usefulness in the development of surrogate markers for vector delivery during the first week after administration. Specifically, we labeled adeno-associated virus serotype 10 expressing the coding sequences for the CLN2 gene implicated in late infantile neuronal ceroid lipofuscinosis with iodine-124. Using direct (Iodogen) and indirect (modified Bolton-Hunter) methods, we observed the vector in the murine brain for up to one week using positron emission tomography. Capsid radioiodination of viral vectors enables non-invasive, whole body, in vivo evaluation of spatial and temporal vector distribution that should inform methods for efficacious gene therapy over a broad range of applications.
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Affiliation(s)
- P. Kothari
- Citigroup Biomedical Imaging Center, Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - B. P. De
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, USA
| | - B. He
- Citigroup Biomedical Imaging Center, Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - A. Chen
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, USA
| | - M. J. Chiuchiolo
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, USA
| | - D. Kim
- Citigroup Biomedical Imaging Center, Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - A. Nikolopoulou
- Citigroup Biomedical Imaging Center, Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - A. Amor-Coarasa
- Citigroup Biomedical Imaging Center, Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - J. P. Dyke
- Citigroup Biomedical Imaging Center, Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - H. U. Voss
- Citigroup Biomedical Imaging Center, Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - S. M. Kaminsky
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, USA
| | - C. P. Foley
- Citigroup Biomedical Imaging Center, Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - S. Vallabhajosula
- Citigroup Biomedical Imaging Center, Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - B. Hu
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, Illinois, USA
| | - S. G. DiMagno
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, Illinois, USA
| | - D. Sondhi
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, USA
| | - R. G. Crystal
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, USA
| | - J. W. Babich
- Citigroup Biomedical Imaging Center, Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - D. Ballon
- Citigroup Biomedical Imaging Center, Department of Radiology, Weill Cornell Medical College, New York, New York, USA
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, USA
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49
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Direct interaction of human serum proteins with AAV virions to enhance AAV transduction: immediate impact on clinical applications. Gene Ther 2016; 24:49-59. [PMID: 27834949 PMCID: PMC5269444 DOI: 10.1038/gt.2016.75] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 10/25/2016] [Accepted: 11/02/2016] [Indexed: 12/19/2022]
Abstract
Recent hemophilia B clinical trials using adeno-associated virus (AAV) gene delivery have demonstrated much lower FIX production in patients compared to the high levels observed in animal models and AAV capsid specific CTLs response elicited at high doses of AAV vectors. These results emphasize the necessity to explore effective approaches for enhancement of AAV transduction. Initially, we found that incubation of all AAV vectors with human serum enhanced AAV transduction. Complementary analytical experiments demonstrated that human serum albumin (HSA) directly interacted with the AAV capsid and augmented AAV transduction. The enhanced transduction was observed with clinical grade HSA. Mechanistic studies suggest that HSA increases AAV binding to target cells and that the interaction of HSA with AAV doesn’t interfere with the AAV infection pathway. Importantly, HSA incubation during vector dialysis also increased transduction. Finally, HSA enhancement of AAV transduction in a model of hemophilia B displayed greater than a 5-fold increase in vector derived circulating FIX, which improved the bleeding phenotype correction. In conclusion, incubation of HSA with AAV vectors supports a universal augmentation of AAV transduction and more importantly, this approach can be immediately transitioned to the clinic for the treatment of hemophilia and other diseases.
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50
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Benskey MJ, Sandoval IM, Manfredsson FP. Continuous Collection of Adeno-Associated Virus from Producer Cell Medium Significantly Increases Total Viral Yield. Hum Gene Ther Methods 2016; 27:32-45. [PMID: 26863210 DOI: 10.1089/hgtb.2015.117] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The ability to efficiently produce large amounts of high-titer recombinant adeno-associated virus (AAV) is a prerequisite to the continued success of AAV as a gene therapy tool targeted toward large-animal preclinical studies or human clinical therapeutics. Current manufacturing procedures necessitate laborious and time-consuming purification procedures to obtain AAV particles of sufficient titer and purity for these demanding biomedical applications. The finding that AAV can be harvested and purified from producer cell medium may represent an efficient alternative to purifying AAV from cellular lysates. Here we sought to determine the maximum duration of time, and frequency within which AAV can be harvested from producer cell medium, in order to maximize the yield obtained from a single transfection preparation. Human embryonic kidney 293T cells were transfected with polyethylenimine to produce AAV2/5 expressing green fluorescent protein (GFP), and cellular medium was harvested every 2 days until a maximum duration of 19 days posttransfection. AAV2/5-GFP was released into producer cell medium at a steady state until 7 days posttransfection, at which time titers dropped dramatically. Harvesting medium every two days resulted in the maximum yield of AAV from a single preparation, and the cumulative yield of AAV harvested from the producer cell medium was 4-fold higher than the yield obtained from a traditional purification of AAV from cellular lysates. The AAV2/5 harvested from medium within the 7-day collection time-course mediated high levels of transduction in vivo, comparable to AAV2/5 harvested from cellular lysates. AAV purified from cell lysates showed increasing amounts of empty particles at 5 and 7 days posttransfection, whereas AAV purified from cell medium did not show an increase in the amount of empty particles throughout the 7-day time course. Finally, we extended these findings to AAV2/9, demonstrating that a comparable ratio of AAV2/9 particles are also released for up to 7 days posttransfection.
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Affiliation(s)
- Matthew J Benskey
- 1 Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University , Grand Rapids, Michigan
| | - Ivette M Sandoval
- 1 Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University , Grand Rapids, Michigan
| | - Fredric P Manfredsson
- 1 Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University , Grand Rapids, Michigan.,2 Mercy Health Saint Mary's , Grand Rapids, Michigan
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