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Słyk Ż, Stachowiak N, Małecki M. Recombinant Adeno-Associated Virus Vectors for Gene Therapy of the Central Nervous System: Delivery Routes and Clinical Aspects. Biomedicines 2024; 12:1523. [PMID: 39062095 PMCID: PMC11274884 DOI: 10.3390/biomedicines12071523] [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: 04/19/2024] [Revised: 06/23/2024] [Accepted: 07/03/2024] [Indexed: 07/28/2024] Open
Abstract
The Central Nervous System (CNS) is vulnerable to a range of diseases, including neurodegenerative and oncological conditions, which present significant treatment challenges. The blood-brain barrier (BBB) restricts molecule penetration, complicating the achievement of therapeutic concentrations in the CNS following systemic administration. Gene therapy using recombinant adeno-associated virus (rAAV) vectors emerges as a promising strategy for treating CNS diseases, demonstrated by the registration of six gene therapy products in the past six years and 87 ongoing clinical trials. This review explores the implementation of rAAV vectors in CNS disease treatment, emphasizing AAV biology and vector engineering. Various administration methods-such as intravenous, intrathecal, and intraparenchymal routes-and experimental approaches like intranasal and intramuscular administration are evaluated, discussing their advantages and limitations in different CNS contexts. Additionally, the review underscores the importance of optimizing therapeutic efficacy through the pharmacokinetics (PK) and pharmacodynamics (PD) of rAAV vectors. A comprehensive analysis of clinical trials reveals successes and challenges, including barriers to commercialization. This review provides insights into therapeutic strategies using rAAV vectors in neurological diseases and identifies areas requiring further research, particularly in optimizing rAAV PK/PD.
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Affiliation(s)
- Żaneta Słyk
- Department of Applied Pharmacy, Faculty of Pharmacy, Medical University of Warsaw, 02-091 Warsaw, Poland
- Laboratory of Gene Therapy, Faculty of Pharmacy, Medical University of Warsaw, 02-091 Warsaw, Poland
| | - Natalia Stachowiak
- Department of Applied Pharmacy, Faculty of Pharmacy, Medical University of Warsaw, 02-091 Warsaw, Poland
| | - Maciej Małecki
- Department of Applied Pharmacy, Faculty of Pharmacy, Medical University of Warsaw, 02-091 Warsaw, Poland
- Laboratory of Gene Therapy, Faculty of Pharmacy, Medical University of Warsaw, 02-091 Warsaw, Poland
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2
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Li X, Wei X, Lin J, Ou L. A versatile toolkit for overcoming AAV immunity. Front Immunol 2022; 13:991832. [PMID: 36119036 PMCID: PMC9479010 DOI: 10.3389/fimmu.2022.991832] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 08/17/2022] [Indexed: 12/12/2022] Open
Abstract
Recombinant adeno-associated virus (AAV) is a promising delivery vehicle for in vivo gene therapy and has been widely used in >200 clinical trials globally. There are already several approved gene therapy products, e.g., Luxturna and Zolgensma, highlighting the remarkable potential of AAV delivery. In the past, AAV has been seen as a relatively non-immunogenic vector associated with low risk of toxicity. However, an increasing number of recent studies indicate that immune responses against AAV and transgene products could be the bottleneck of AAV gene therapy. In clinical studies, pre-existing antibodies against AAV capsids exclude many patients from receiving the treatment as there is high prevalence of antibodies among humans. Moreover, immune response could lead to loss of efficacy over time and severe toxicity, manifested as liver enzyme elevations, kidney injury, and thrombocytopenia, resulting in deaths of non-human primates and patients. Therefore, extensive efforts have been attempted to address these issues, including capsid engineering, plasmapheresis, IgG proteases, CpG depletion, empty capsid decoy, exosome encapsulation, capsid variant switch, induction of regulatory T cells, and immunosuppressants. This review will discuss these methods in detail and highlight important milestones along the way.
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Affiliation(s)
- Xuefeng Li
- The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People’s Hospital; State Key Laboratory of Respiratory Disease, Sino-French Hoffmann Institute, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, China
- Shenzhen Luohu People’s Hospital, The Third Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Xiaoli Wei
- Guangzhou Dezheng Biotechnology Co., Ltd., Guangzhou, China
| | - Jinduan Lin
- The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People’s Hospital; State Key Laboratory of Respiratory Disease, Sino-French Hoffmann Institute, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, China
| | - Li Ou
- Genemagic Biosciences, Philadelphia, PA, United States
- Department of Pediatrics, University of Minnesota, Minneapolis, MN, United States
- *Correspondence: Li Ou,
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3
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Abstract
Gene transfer using adeno-associated viral (AAV) vectors has made tremendous progress in the last decade and has achieved cures of debilitating diseases such as hemophilia A and B. Nevertheless, progress is still being hampered by immune responses against the AAV capsid antigens or the transgene products. Immunosuppression designed to blunt T cell responses has shown success in some patients but failed in others especially if they received very high AAV vectors doses. Although it was initially thought that AAV vectors induce only marginal innate responses below the threshold of systemic symptoms recent trials have shown that complement activation can results in serious adverse events. Dorsal root ganglia toxicity has also been identified as a complication of high vector doses as has severe hepatotoxicity. Most of the critical complications occur in patients who are treated with very high vector doses indicating that the use of more efficient AAV vectors to allow for dose sparing or giving smaller doses repeatedly, the latter in conjunction with antibody or B cell depleting measures, should be explored.
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Affiliation(s)
- Hildegund C. J. Ertl
- Ertl Laboratory, Vaccine Center, The Wistar Institute, Philadelphia, PA, United States
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4
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Becirovic E. Maybe you can turn me on: CRISPRa-based strategies for therapeutic applications. Cell Mol Life Sci 2022; 79:130. [PMID: 35152318 PMCID: PMC8840918 DOI: 10.1007/s00018-022-04175-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 01/24/2022] [Accepted: 01/27/2022] [Indexed: 12/17/2022]
Abstract
AbstractSince the revolutionary discovery of the CRISPR-Cas technology for programmable genome editing, its range of applications has been extended by multiple biotechnological tools that go far beyond its original function as “genetic scissors”. One of these further developments of the CRISPR-Cas system allows genes to be activated in a targeted and efficient manner. These gene-activating CRISPR-Cas modules (CRISPRa) are based on a programmable recruitment of transcription factors to specific loci and offer several key advantages that make them particularly attractive for therapeutic applications. These advantages include inter alia low off-target effects, independence of the target gene size as well as the potential to develop gene- and mutation-independent therapeutic strategies. Herein, I will give an overview on the currently available CRISPRa modules and discuss recent developments, future potentials and limitations of this approach with a focus on therapeutic applications and in vivo delivery.
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Affiliation(s)
- Elvir Becirovic
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany.
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Rapti K, Grimm D. Adeno-Associated Viruses (AAV) and Host Immunity - A Race Between the Hare and the Hedgehog. Front Immunol 2021; 12:753467. [PMID: 34777364 PMCID: PMC8586419 DOI: 10.3389/fimmu.2021.753467] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 09/28/2021] [Indexed: 12/12/2022] Open
Abstract
Adeno-associated viruses (AAV) have emerged as the lead vector in clinical trials and form the basis for several approved gene therapies for human diseases, mainly owing to their ability to sustain robust and long-term in vivo transgene expression, their amenability to genetic engineering of cargo and capsid, as well as their moderate toxicity and immunogenicity. Still, recent reports of fatalities in a clinical trial for a neuromuscular disease, although linked to an exceptionally high vector dose, have raised new caution about the safety of recombinant AAVs. Moreover, concerns linger about the presence of pre-existing anti-AAV antibodies in the human population, which precludes a significant percentage of patients from receiving, and benefitting from, AAV gene therapies. These concerns are exacerbated by observations of cellular immune responses and other adverse events, including detrimental off-target transgene expression in dorsal root ganglia. Here, we provide an update on our knowledge of the immunological and molecular race between AAV (the “hedgehog”) and its human host (the “hare”), together with a compendium of state-of-the-art technologies which provide an advantage to AAV and which, thus, promise safer and more broadly applicable AAV gene therapies in the future.
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Affiliation(s)
- Kleopatra Rapti
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, Heidelberg, Germany.,BioQuant Center, BQ0030, University of Heidelberg, Heidelberg, Germany
| | - Dirk Grimm
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, Heidelberg, Germany.,BioQuant Center, BQ0030, University of Heidelberg, Heidelberg, Germany.,German Center for Infection Research Deutsches Zentrum für Infektionsforschung (DZIF) and German Center for Cardiovascular Research Deutsches Zentrum für Herz-Kreislauf-Erkrankungen (DZHK), Partner Site Heidelberg, Heidelberg, Germany
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Tustian AD, Bak H. Assessment of quality attributes for adeno-associated viral vectors. Biotechnol Bioeng 2021; 118:4186-4203. [PMID: 34309017 DOI: 10.1002/bit.27905] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/21/2021] [Accepted: 07/22/2021] [Indexed: 12/24/2022]
Abstract
There is a strong and growing interest in the development and production of gene therapy products, including those utilizing adeno-associated virus (AAV) particles. This is evident with the increase in the number of clinical trials and agency approvals for AAV therapeutics. As bioproduction of AAV viral vectors matures, a quality by design (QbD) approach to process development can aid in process robustness and product quality. Furthermore, it may become a regulatory expectation. The first step in any QbD approach is to determine what physical, chemical, biological, or microbiological property or characteristic product attributes should be controlled within an appropriate limit, range, or distribution to ensure the desired product quality. Then predefined goals are set to allow proactive process development to design in quality. This review lists typical quality attributes used for release testing of AAV viral vectors and discusses these and selected attributes important to extended characterization studies in terms of safety, efficacy, and impact upon the patient immune response.
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Affiliation(s)
| | - Hanne Bak
- Regeneron Pharmaceuticals Inc., Tarrytown, NY, USA
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Zhu D, Schieferecke AJ, Lopez PA, Schaffer DV. Adeno-Associated Virus Vector for Central Nervous System Gene Therapy. Trends Mol Med 2021; 27:524-537. [PMID: 33895085 DOI: 10.1016/j.molmed.2021.03.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 03/15/2021] [Accepted: 03/22/2021] [Indexed: 12/14/2022]
Abstract
The past several years have witnessed significant advances in the development of therapeutic gene delivery for neurological disorders of the central nervous system (CNS). In particular, genome-wide sequencing analysis has deepened our understanding of mutations that underlie many monogenic disorders, which in turn has contributed to clinical advances involving adeno-associated virus (AAV) vector delivery of replacement genes to treat recessive disorders. Moreover, gene therapy has been further bolstered with advances in genome editing tools that allow researchers to silence, repair, and amend endogenous genes. However, despite strong preclinical and clinical progress, challenges remain, including delivery and safety. Here, we discuss advances in AAV engineering, recent developments in cargo design, and translation of these technologies towards clinical progress.
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Affiliation(s)
- Danqing Zhu
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA, 94720, USA
| | - Adam J Schieferecke
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, 94720, USA
| | - Paola A Lopez
- Department of Bioengineering, University of California, Berkeley, CA, 94720, USA
| | - David V Schaffer
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA, 94720, USA; Department of Molecular and Cell Biology, University of California, Berkeley, CA, 94720, USA; Department of Bioengineering, University of California, Berkeley, CA, 94720, USA; Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, 94720, USA; Helen Wills Neuroscience Institute, University of California, Berkeley, CA, 94720, USA.
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Piechnik M, Sawamoto K, Ohnishi H, Kawamoto N, Ago Y, Tomatsu S. Evading the AAV Immune Response in Mucopolysaccharidoses. Int J Mol Sci 2020; 21:E3433. [PMID: 32414007 PMCID: PMC7279460 DOI: 10.3390/ijms21103433] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 05/11/2020] [Accepted: 05/12/2020] [Indexed: 12/31/2022] Open
Abstract
The humoral immune response elicited by adeno-associated virus (AAV)-mediated gene therapy for the treatment of mucopolysaccharidoses (MPS) poses a significant challenge to achieving therapeutic levels of transgene expression. Antibodies targeting the AAV capsid as well as the transgene product diminish the production of glycosaminoglycan (GAG)-degrading enzymes essential for the treatment of MPS. Patients who have antibodies against AAV capsid increase in number with age, serotype, and racial background and are excluded from the clinical trials at present. In addition, patients who have undergone AAV gene therapy are often excluded from the additional AAV gene therapy with the same serotype, since their acquired immune response (antibody) against AAV will limit further efficacy of treatment. Several methods are being developed to overcome this immune response, such as novel serotype design, antibody reduction by plasmapheresis and immunosuppression, and antibody evasion using empty capsids and enveloped AAV vectors. In this review, we examine the mechanisms of the anti-AAV humoral immune response and evaluate the strengths and weaknesses of current evasion strategies in order to provide an evidence-based recommendation on evading the immune response for future AAV-mediated gene therapies for MPS.
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Affiliation(s)
- Matthew Piechnik
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA; (M.P.); (K.S.)
- Department of Medical and Molecular Sciences, University of Delaware, Newark, DE 19716, USA
| | - Kazuki Sawamoto
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA; (M.P.); (K.S.)
| | - Hidenori Ohnishi
- Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu 501-1194, Japan; (H.O.); (N.K.); (Y.A.)
| | - Norio Kawamoto
- Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu 501-1194, Japan; (H.O.); (N.K.); (Y.A.)
| | - Yasuhiko Ago
- Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu 501-1194, Japan; (H.O.); (N.K.); (Y.A.)
| | - Shunji Tomatsu
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA; (M.P.); (K.S.)
- Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu 501-1194, Japan; (H.O.); (N.K.); (Y.A.)
- Department of Pediatrics, Shimane University, Shimane 690-8504, Japan
- Department of Pediatrics, Thomas Jefferson University, Philadelphia, PA 19107, USA
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Sawamoto K, Álvarez González JV, Piechnik M, Otero FJ, Couce ML, Suzuki Y, Tomatsu S. Mucopolysaccharidosis IVA: Diagnosis, Treatment, and Management. Int J Mol Sci 2020; 21:E1517. [PMID: 32102177 PMCID: PMC7073202 DOI: 10.3390/ijms21041517] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 02/15/2020] [Accepted: 02/19/2020] [Indexed: 12/16/2022] Open
Abstract
Mucopolysaccharidosis type IVA (MPS IVA, or Morquio syndrome type A) is an inherited metabolic lysosomal disease caused by the deficiency of the N-acetylglucosamine-6-sulfate sulfatase enzyme. The deficiency of this enzyme accumulates the specific glycosaminoglycans (GAG), keratan sulfate, and chondroitin-6-sulfate mainly in bone, cartilage, and its extracellular matrix. GAG accumulation in these lesions leads to unique skeletal dysplasia in MPS IVA patients. Clinical, radiographic, and biochemical tests are needed to complete the diagnosis of MPS IVA since some clinical characteristics in MPS IVA are overlapped with other disorders. Early and accurate diagnosis is vital to optimizing patient management, which provides a better quality of life and prolonged life-time in MPS IVA patients. Currently, enzyme replacement therapy (ERT) and hematopoietic stem cell transplantation (HSCT) are available for patients with MPS IVA. However, ERT and HSCT do not have enough impact on bone and cartilage lesions in patients with MPS IVA. Penetrating the deficient enzyme into an avascular lesion remains an unmet challenge, and several innovative therapies are under development in a preclinical study. In this review article, we comprehensively describe the current diagnosis, treatment, and management for MPS IVA. We also illustrate developing future therapies focused on the improvement of skeletal dysplasia in MPS IVA.
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Affiliation(s)
- Kazuki Sawamoto
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA; (K.S.); (J.V.Á.G.); (M.P.)
| | | | - Matthew Piechnik
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA; (K.S.); (J.V.Á.G.); (M.P.)
- University of Delaware, Newark, DE 19716, USA
| | - Francisco J. Otero
- Department of Pharmacology, Pharmacy and Pharmaceutical Technology, School of Pharmacy, University of Santiago de Compostela, 15872 Santiago de Compostela, Spain;
| | - Maria L. Couce
- Department of Forensic Sciences, Pathology, Gynecology and Obstetrics and Pediatrics Neonatology Service, Metabolic Unit, IDIS, CIBERER, MetabERN, University Clinic Hospital of Santiago de Compostela, 15706 Santiago de Compostela, Spain;
| | - Yasuyuki Suzuki
- Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu 501-1193, Japan;
| | - Shunji Tomatsu
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA; (K.S.); (J.V.Á.G.); (M.P.)
- University of Delaware, Newark, DE 19716, USA
- Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu 501-1193, Japan;
- Department of Pediatrics, Thomas Jefferson University, Philadelphia, PA 19107, USA
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Mary B, Maurya S, Arumugam S, Kumar V, Jayandharan GR. Post-translational modifications in capsid proteins of recombinant adeno-associated virus (AAV) 1-rh10 serotypes. FEBS J 2019; 286:4964-4981. [PMID: 31330090 PMCID: PMC7496479 DOI: 10.1111/febs.15013] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 05/13/2019] [Accepted: 07/19/2019] [Indexed: 01/27/2023]
Abstract
Post‐translational modifications in viral capsids are known to fine‐tune and regulate several aspects of the infective life cycle of several viruses in the host. Recombinant viruses that are generated in a specific producer cell line are likely to inherit unique post‐translational modifications during intra‐cellular maturation of its capsid proteins. Data on such post‐translational modifications in the capsid of recombinant adeno‐associated virus serotypes (AAV1‐rh10) is limited. We have employed liquid chromatography and mass spectrometry analysis to characterize post‐translational modifications in AAV1‐rh10 capsid protein. Our analysis revealed a total of 52 post‐translational modifications in AAV2‐AAVrh10 capsids, including ubiquitination (17%), glycosylation (36%), phosphorylation (21%), SUMOylation (13%) and acetylation (11%). While AAV1 had no detectable post‐translational modification, at least four AAV serotypes had >7 post‐translational modifications in their capsid protein. About 82% of these post‐translational modifications are novel. A limited validation of AAV2 capsids by MALDI‐TOF and western blot analysis demonstrated minimal glycosylation and ubiquitination of AAV2 capsids. To further validate this, we disrupted a glycosylation site identified in AAV2 capsid (AAV2‐N253Q), which severely compromised its packaging efficiency (~ 100‐fold vs. AAV2 wild‐type vectors). In order to confirm other post‐translational modifications detected such as SUMOylation, mutagenesis of a SUMOylation site(K258Q) in AAV2 was performed. This mutant vector demonstrated reduced levels of SUMO‐1/2/3 proteins and negligible transduction, 2 weeks after ocular gene transfer. Our study underscores the heterogeneity of post‐translational modifications in AAV vectors. The data presented here, should facilitate further studies to understand the biological relevance of post‐translational modifications in AAV life cycle and the development of novel bioengineered AAV vectors for gene therapy applications. Enzymes Trypsin, EC 3.4.21.4
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Affiliation(s)
- Bertin Mary
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India
| | - Shubham Maurya
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India
| | - Sathyathithan Arumugam
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India.,SASTRA University, Thanjavur, India
| | - Vikas Kumar
- Mass Spectrometry and Proteomics Core Facility, University of Nebraska Medical Center, Omaha, NE, USA
| | - Giridhara R Jayandharan
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India.,Department of Haematology and Centre for Stem Cell Research, Vellore, India
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Barnes C, Scheideler O, Schaffer D. Engineering the AAV capsid to evade immune responses. Curr Opin Biotechnol 2019; 60:99-103. [PMID: 30807882 DOI: 10.1016/j.copbio.2019.01.002] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 01/07/2019] [Indexed: 12/13/2022]
Abstract
Gene therapy is progressively emerging as a promising and powerful therapeutic modality, and adeno-associated virus (AAV) is a major delivery vehicle for such therapies. Among the most significant challenges that limit AAV's utility, however, is the immune response it elicits. Antibodies elicited by prior exposure to natural virus or vector can bind to an AAV vector, preventing it from entering the cell. Furthermore, even if AAV manages to infect a target cell, these cells can then be attenuated by lymphocytes. Improvements in our understanding of how the immune system responds to AAV have guided engineering of the capsid to reduce those responses, yielding capsid variants that are much stealthier and more effective. This review summarizes recent advances in understanding the immune response to AAV as well as highlights engineering methods that enhance AAV's potential as a gene therapy vector.
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Affiliation(s)
- Christopher Barnes
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, USA
| | - Olivia Scheideler
- Department of Bioengineering, University of California, Berkeley, CA, USA; The UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley, CA 94720, USA
| | - David Schaffer
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, USA; Department of Bioengineering, University of California, Berkeley, CA, USA; The Helen Wills Neuroscience Institute, University of California, Berkeley, CA, USA; Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.
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