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Critchley BJ, Gaspar HB, Benedetti S. Targeting the central nervous system in lysosomal storage diseases: Strategies to deliver therapeutics across the blood-brain barrier. Mol Ther 2023; 31:657-675. [PMID: 36457248 PMCID: PMC10014236 DOI: 10.1016/j.ymthe.2022.11.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 11/18/2022] [Accepted: 11/28/2022] [Indexed: 12/02/2022] Open
Abstract
Lysosomal storage diseases (LSDs) are multisystem inherited metabolic disorders caused by dysfunctional lysosomal activity, resulting in the accumulation of undegraded macromolecules in a variety of organs/tissues, including the central nervous system (CNS). Treatments include enzyme replacement therapy, stem/progenitor cell transplantation, and in vivo gene therapy. However, these treatments are not fully effective in treating the CNS as neither enzymes, stem cells, nor viral vectors efficiently cross the blood-brain barrier. Here, we review the latest advancements in improving delivery of different therapeutic agents to the CNS and comment upon outstanding questions in the field of neurological LSDs.
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Affiliation(s)
- Bethan J Critchley
- Infection, Immunity and Inflammation Research & Teaching Department, UCL Great Ormond Street Institute of Child Health, Zayed Centre for Research, London WC1N 1DZ, UK
| | - H Bobby Gaspar
- Infection, Immunity and Inflammation Research & Teaching Department, UCL Great Ormond Street Institute of Child Health, Zayed Centre for Research, London WC1N 1DZ, UK; Orchard Therapeutics Ltd., London EC4N 6EU, UK
| | - Sara Benedetti
- Infection, Immunity and Inflammation Research & Teaching Department, UCL Great Ormond Street Institute of Child Health, Zayed Centre for Research, London WC1N 1DZ, UK; NIHR Great Ormond Street Hospital Biomedical Research Centre, London, UK.
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2
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Meng Y, Pople CB, Huang Y, Jones RM, Ottoy J, Goubran M, Oliveira LM, Davidson B, Lawrence LS, Lau AZ, Bethune A, Maralani P, Abrahao A, Hamani C, Hynynen K, Kalia SK, Lipsman N, Kalia LV. Putaminal Recombinant Glucocerebrosidase Delivery with Magnetic Resonance
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Guided Focused Ultrasound in Parkinson's Disease: A Phase I Study. Mov Disord 2022; 37:2134-2139. [DOI: 10.1002/mds.29190] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 07/01/2022] [Accepted: 07/19/2022] [Indexed: 12/27/2022] Open
Affiliation(s)
- Ying Meng
- Division of Neurosurgery, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Hurvitz Brain Sciences Research Program Harquail Centre for Neuromodulation, Sunnybrook Research Institute Toronto Canada
| | - Christopher B. Pople
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Hurvitz Brain Sciences Research Program Harquail Centre for Neuromodulation, Sunnybrook Research Institute Toronto Canada
| | - Yuexi Huang
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
| | - Ryan M. Jones
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
| | - Julie Ottoy
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Hurvitz Brain Sciences Research Program Harquail Centre for Neuromodulation, Sunnybrook Research Institute Toronto Canada
| | - Maged Goubran
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Hurvitz Brain Sciences Research Program Harquail Centre for Neuromodulation, Sunnybrook Research Institute Toronto Canada
- Department of Medical Biophysics University of Toronto Toronto Canada
| | - Lais M. Oliveira
- Krembil Research Institute University Health Network, University of Toronto Toronto Canada
| | - Benjamin Davidson
- Division of Neurosurgery, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Hurvitz Brain Sciences Research Program Harquail Centre for Neuromodulation, Sunnybrook Research Institute Toronto Canada
| | - Liam S.P. Lawrence
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
| | - Angus Z. Lau
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Department of Medical Biophysics University of Toronto Toronto Canada
| | - Allison Bethune
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Hurvitz Brain Sciences Research Program Harquail Centre for Neuromodulation, Sunnybrook Research Institute Toronto Canada
| | - Pejman Maralani
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Department of Medical Imaging, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
| | - Agessandro Abrahao
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Hurvitz Brain Sciences Research Program Harquail Centre for Neuromodulation, Sunnybrook Research Institute Toronto Canada
- Department of Medicine, Division of Neurology Sunnybrook Health Sciences Centre, University of Toronto Toronto Canada
| | - Clement Hamani
- Division of Neurosurgery, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Hurvitz Brain Sciences Research Program Harquail Centre for Neuromodulation, Sunnybrook Research Institute Toronto Canada
| | - Kullervo Hynynen
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Department of Medical Biophysics University of Toronto Toronto Canada
| | - Suneil K. Kalia
- Krembil Research Institute University Health Network, University of Toronto Toronto Canada
- Division of Neurosurgery Toronto Western Hospital, University Health Network, University of Toronto Toronto Canada
- KITE Research Institute, University Health Network, University of Toronto Toronto Canada
| | - Nir Lipsman
- Division of Neurosurgery, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre University of Toronto Toronto Canada
- Hurvitz Brain Sciences Research Program Harquail Centre for Neuromodulation, Sunnybrook Research Institute Toronto Canada
| | - Lorraine V. Kalia
- Krembil Research Institute University Health Network, University of Toronto Toronto Canada
- Division of Neurology Toronto Western Hospital, University Health Network, University of Toronto Toronto Canada
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Song R, Zhang C, Teng F, Tu J, Guo X, Fan Z, Zheng Y, Zhang D. Cavitation-facilitated transmembrane permeability enhancement induced by acoustically vaporized nanodroplets. ULTRASONICS SONOCHEMISTRY 2021; 79:105790. [PMID: 34662804 PMCID: PMC8526759 DOI: 10.1016/j.ultsonch.2021.105790] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/09/2021] [Accepted: 10/12/2021] [Indexed: 05/05/2023]
Abstract
Ultrasound-facilitated transmembrane permeability enhancement has attracted broad attention in the treatment of central nervous system (CNS) diseases, by delivering gene/drugs into the deep site of brain tissues with a safer and more effective way. Although the feasibility of using acoustically vaporized nanodroplets to open the blood-brain-barrier (BBB) has previously been reported, the relevant physical mechanisms and impact factors are not well known. In the current study, a nitrocellulose (NC) membrane was used to mimic the multi-layered pore structure of BBB. The cavitation activity and the penetration ability of phase-changed nanodroplets were systemically evaluated at different concentration levels, and compared with the results obtained for SonoVue microbubbles. Passive cavitation detection showed that less intensified but more sustained inertial cavitation (IC) activity would be generated by vaporized nanodroplets than microbubbles. As the results, with a sufficiently high concentration (∼5 × 108/mL), phase-changed nanodroplets were more effective than microbubbles in enabling a fluorescent tracer agent (FITC, 150 kDa) to penetrate deeper and more homogeneously through the NC membrane, and a positive correlation was observed between accumulated IC dose and the amount of penetrated FITC. In vivo studies further confirmed acoustically vaporized nanodroplets performed better than microbubbles by opening the BBB in rats' brains. These results indicated that phase-changed nanodroplets can be used as a safe, efficient and durable agent to achieve satisfactory cavitation-mediated permeability enhancement effect in biomedical applications.
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Affiliation(s)
- Renjie Song
- Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093, China
| | - Chunbing Zhang
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Fengmeng Teng
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Juan Tu
- Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093, China; The State Key Laboratory of Acoustics, Chinese Academy of Science, Beijing 10080, China.
| | - Xiasheng Guo
- Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093, China
| | - Zheng Fan
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Yinfei Zheng
- Research Center for Intelligent Sensing, Zhejiang Lab, Hangzhou 311100, China.
| | - Dong Zhang
- Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093, China; The State Key Laboratory of Acoustics, Chinese Academy of Science, Beijing 10080, China.
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Hurdles in treating Hurler disease: potential routes to achieve a "real" cure. Blood Adv 2021; 4:2837-2849. [PMID: 32574368 DOI: 10.1182/bloodadvances.2020001708] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 05/06/2020] [Indexed: 12/13/2022] Open
Abstract
Mucopolysaccharidoses (MPSs) are multiorgan devastating diseases for which hematopoietic cell transplantation (HCT) and, to a lesser extent, enzyme replacement therapy have substantially altered the course of the disease. Furthermore, they have resulted in increased overall survival, especially for Hurler disease (MPS-1). However, despite the identification of clinical predictors and harmonized transplantation protocols, disease progression still poses a significant burden to patients, although at a slower pace. To design better therapies, we need to understand why and where current therapies fail. In this review, we discuss important aspects of the underlying disease and the disease progression. We note that the majority of progressive symptoms that occur in "hard-to-treat" tissues are actually tissues that are difficult to reach, such as avascular connective tissue or tissues isolated from the circulation by a specific barrier (eg, blood-brain barrier, blood-retina barrier). Although easily reached tissues are effectively cured by HCT, disease progression is observed in these "hard-to-reach" tissues. We used these insights to critically appraise ongoing experimental endeavors with regard to their potential to overcome the encountered hurdles and improve long-term clinical outcomes in MPS patients treated with HCT.
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Recent Advances on Ultrasound Contrast Agents for Blood-Brain Barrier Opening with Focused Ultrasound. Pharmaceutics 2020; 12:pharmaceutics12111125. [PMID: 33233374 PMCID: PMC7700476 DOI: 10.3390/pharmaceutics12111125] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/16/2020] [Accepted: 11/17/2020] [Indexed: 12/14/2022] Open
Abstract
The blood-brain barrier is the primary obstacle to efficient intracerebral drug delivery. Focused ultrasound, in conjunction with microbubbles, is a targeted and non-invasive way to disrupt the blood-brain barrier. Many commercially available ultrasound contrast agents and agents specifically designed for therapeutic purposes have been investigated in ultrasound-mediated blood-brain barrier opening studies. The new generation of sono-sensitive agents, such as liquid-core droplets, can also potentially disrupt the blood-brain barrier after their ultrasound-induced vaporization. In this review, we describe the different compositions of agents used for ultrasound-mediated blood-brain barrier opening in recent studies, and we discuss the challenges of the past five years related to the optimal formulation of agents.
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Beccaria K, Sabbagh A, de Groot J, Canney M, Carpentier A, Heimberger AB. Blood-brain barrier opening with low intensity pulsed ultrasound for immune modulation and immune therapeutic delivery to CNS tumors. J Neurooncol 2020; 151:65-73. [PMID: 32112296 DOI: 10.1007/s11060-020-03425-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 02/05/2020] [Indexed: 12/25/2022]
Abstract
INTRODUCTION Opening of the blood-brain barrier (BBB) by pulsed low intensity ultrasound has been developed during the last decade and is now recognized as a safe technique to transiently and repeatedly open the BBB. This non- or minimally invasive technique allows for a targeted and uniform dispersal of a wide range of therapeutic substances throughout the brain, including immune cells and antibodies. METHODS In this review article, we summarize pre-clinical studies that have used BBB-opening by pulsed low intensity ultrasound to enhance the delivery of immune therapeutics and effector cell populations, as well as several recent clinical studies that have been initiated. Based on this analysis, we propose immune therapeutic strategies that are most likely to benefit from this strategy. The literature review and trial data research were performed using Medline/Pubmed databases and clinical trial registry www.clinicaltrials.gov . The reference lists of all included articles were searched for additional studies. RESULTS A wide range of immune therapeutic agents, including small molecular weight drugs, antibodies or NK cells, have been safely and efficiently delivered to the brain with pulsed low intensity ultrasound in preclinical models, and both tumor control and increased survival have been demonstrated in different types of brain tumor models in rodents. Ultrasound-induced BBB disruption may also stimulate innate and cellular immune responses. CONCLUSIONS Ultrasound BBB opening has just recently entered clinical trials with encouraging results, and the association of this strategy with immune therapeutics creates a new field of brain tumor treatment.
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Affiliation(s)
- Kevin Beccaria
- Department of Neurosurgery, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Aria Sabbagh
- Department of Neurosurgery, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - John de Groot
- Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Michael Canney
- CarThera, Institut du Cerveau Et de La Moelle épinière (ICM), 75013, Paris, France
| | - Alexandre Carpentier
- Department of Neurosurgery, Sorbonne Université, UPMC Univ Paris 06, Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpitaux Universitaires La Pitié-Salpêtrière, Paris, France
| | - Amy B Heimberger
- Department of Neurosurgery, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.
- Department of Neurosurgery, The University of Texas MD Anderson Cancer Center, Unit 422, P.O. Box 301402, Houston, TX, 77230-1402, USA.
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Abstract
Mucopolysaccharidoses (MPS) are inborn errors of metabolism produced by a deficiency of one of the enzymes involved in the degradation of glycosaminoglycans (GAGs). Although taken separately, each type is rare. As a group, MPS are relatively frequent, with an overall estimated incidence of around 1 in 20,000-25,000 births. Development of therapeutic options for MPS, including hematopoietic stem cell transplantation (HSCT) and enzyme replacement therapy (ERT), has modified the natural history of many MPS types. In spite of the improvement in some tissues and organs, significant challenges remain unsolved, including blood-brain barrier (BBB) penetration and treatment of lesions in avascular cartilage, heart valves, and corneas. Newer approaches, such as intrathecal ERT, ERT with fusion proteins to cross the BBB, gene therapy, substrate reduction therapy (SRT), chaperone therapy, and some combination of these strategies may provide better outcomes for MPS patients in the near future. As early diagnosis and early treatment are imperative to improve therapeutic efficacy, the inclusion of MPS in newborn screening programs should enhance the potential impact of treatment in reducing the morbidity associated with MPS diseases. In this review, we evaluate available treatments, including ERT and HSCT, and future treatments, such as gene therapy, SRT, and chaperone therapy, and describe the advantages and disadvantages. We also assess the current clinical endpoints and biomarkers used in clinical trials.
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Meng Y, Pople CB, Lea-Banks H, Abrahao A, Davidson B, Suppiah S, Vecchio LM, Samuel N, Mahmud F, Hynynen K, Hamani C, Lipsman N. Safety and efficacy of focused ultrasound induced blood-brain barrier opening, an integrative review of animal and human studies. J Control Release 2019; 309:25-36. [PMID: 31326464 DOI: 10.1016/j.jconrel.2019.07.023] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 07/16/2019] [Accepted: 07/17/2019] [Indexed: 12/22/2022]
Abstract
The blood-brain barrier, while fundamental in maintaining homeostasis in the central nervous system, is a bottleneck to achieving efficacy for numerous therapeutics. Improved brain penetration is also desirable for reduced dose, cost, and systemic side effects. Transient disruption of the blood-brain barrier with focused ultrasound (FUS) can facilitate drug delivery noninvasively with precise spatial and temporal specificity. FUS technology is transcranial and effective without further drug modifications, key advantages that will accelerate adoption and translation of existing therapeutic pipelines. In this review, we performed a comprehensive literature search to build a database and provide a synthesis of ultrasound parameters and drug characteristics that influence the safety and efficacy profile of FUS to enhance drug delivery.
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Affiliation(s)
- Ying Meng
- Division of Neurosurgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada; Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada
| | - Christopher B Pople
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada
| | - Harriet Lea-Banks
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada
| | - Agessandro Abrahao
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada; Department of Medicine (Neurology), Sunnybrook Health Sciences Centre and University of Toronto, Toronto, Canada
| | - Benjamin Davidson
- Division of Neurosurgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada; Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada
| | - Suganth Suppiah
- Division of Neurosurgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada
| | - Laura M Vecchio
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada
| | - Nardin Samuel
- Division of Neurosurgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada
| | - Faiza Mahmud
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada
| | - Kullervo Hynynen
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Canada
| | - Clement Hamani
- Division of Neurosurgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada; Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada; Hurvitz Brain Sciences Research Program, Harquail Centre for Neuromodulation, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada
| | - Nir Lipsman
- Division of Neurosurgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada; Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada; Hurvitz Brain Sciences Research Program, Harquail Centre for Neuromodulation, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada.
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Christensen CL, Ashmead RE, Choy FYM. Cell and Gene Therapies for Mucopolysaccharidoses: Base Editing and Therapeutic Delivery to the CNS. Diseases 2019; 7:E47. [PMID: 31248000 PMCID: PMC6787741 DOI: 10.3390/diseases7030047] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 06/21/2019] [Accepted: 06/25/2019] [Indexed: 02/06/2023] Open
Abstract
Although individually uncommon, rare diseases collectively account for a considerable proportion of disease impact worldwide. A group of rare genetic diseases called the mucopolysaccharidoses (MPSs) are characterized by accumulation of partially degraded glycosaminoglycans cellularly. MPS results in varied systemic symptoms and in some forms of the disease, neurodegeneration. Lack of treatment options for MPS with neurological involvement necessitates new avenues of therapeutic investigation. Cell and gene therapies provide putative alternatives and when coupled with genome editing technologies may provide long term or curative treatment. Clustered regularly interspaced short palindromic repeats (CRISPR)-based genome editing technology and, more recently, advances in genome editing research, have allowed for the addition of base editors to the repertoire of CRISPR-based editing tools. The latest versions of base editors are highly efficient on-targeting deoxyribonucleic acid (DNA) editors. Here, we describe a number of putative guide ribonucleic acid (RNA) designs for precision correction of known causative mutations for 10 of the MPSs. In this review, we discuss advances in base editing technologies and current techniques for delivery of cell and gene therapies to the site of global degeneration in patients with severe neurological forms of MPS, the central nervous system, including ultrasound-mediated blood-brain barrier disruption.
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Affiliation(s)
- Chloe L Christensen
- Department of Biology, Centre for Biomedical Research, University of Victoria, 3800 Finnerty Rd., Victoria, BC V8P 5C2, Canada
| | - Rhea E Ashmead
- Department of Biology, Centre for Biomedical Research, University of Victoria, 3800 Finnerty Rd., Victoria, BC V8P 5C2, Canada
| | - Francis Y M Choy
- Department of Biology, Centre for Biomedical Research, University of Victoria, 3800 Finnerty Rd., Victoria, BC V8P 5C2, Canada.
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