1
|
Battista M, Carelli V, Bottazzi L, Bandello F, Cascavilla ML, Barboni P. Gene therapy for Leber hereditary optic neuropathy. Expert Opin Biol Ther 2024; 24:521-528. [PMID: 38939999 DOI: 10.1080/14712598.2024.2359015] [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: 12/02/2023] [Accepted: 05/20/2024] [Indexed: 06/29/2024]
Abstract
INTRODUCTION Leber hereditary optic neuropathy (LHON) is among the most frequent inherited mitochondrial disease, causing a severe visual impairment, mostly in young-adult males. The causative mtDNA variants (the three common are m.11778 G>A/MT-ND4, m.3460 G>A/MT-ND1, and m.14484T>C/MT-ND6) by affecting complex I impair oxidative phosphorylation in retinal ganglion cells, ultimately leading to irreversible cell death and consequent functional loss. The gene therapy based on allotopic expression of a wild-type transgene carried by adeno-associated viral vectors (AVV-based) appears a promising approach in mitochondrial disease and its efficacy has been explored in several large clinical trials. AREAS COVERED The review work employed basic concepts in mitochondrial diseases, LHON, and gene therapy procedures. Reports from completed trials in LHON (i.e. RESCUE) were reviewed and critically compared. EXPERT OPINION New challenges, as the improvement of the contralateral untreated eye or the apparently better outcome in patients treated in later stages (6-12 months), were highlighted by the latest gene therapy trials. A better understanding of the pathogenetic mechanisms of the disease together with combined therapy (medical and gene therapy) and optimization in genetic correction approaches could improve the visual outcome of treated eyes.
Collapse
Affiliation(s)
- Marco Battista
- Department of Ophthalmology, University Vita-Salute, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Valerio Carelli
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
- Programma di Neurogenetica, IRCCS Istituto di Scienze Neurologiche di Bologna, Bologna, Italy
| | - Leonardo Bottazzi
- Department of Ophthalmology, University Vita-Salute, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Francesco Bandello
- Department of Ophthalmology, University Vita-Salute, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Maria Lucia Cascavilla
- Department of Ophthalmology, University Vita-Salute, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Piero Barboni
- Department of Ophthalmology, University Vita-Salute, IRCCS Ospedale San Raffaele, Milan, Italy
- Studio Oculistico d'Azeglio, Bologna, Italy
| |
Collapse
|
2
|
Gao Y, Guo L, Wang F, Wang Y, Li P, Zhang D. Development of mitochondrial gene-editing strategies and their potential applications in mitochondrial hereditary diseases: a review. Cytotherapy 2024; 26:11-24. [PMID: 37930294 DOI: 10.1016/j.jcyt.2023.10.004] [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: 06/08/2023] [Revised: 10/12/2023] [Accepted: 10/13/2023] [Indexed: 11/07/2023]
Abstract
Mitochondrial DNA (mtDNA) is a critical genome contained within the mitochondria of eukaryotic cells, with many copies present in each mitochondrion. Mutations in mtDNA often are inherited and can lead to severe health problems, including various inherited diseases and premature aging. The lack of efficient repair mechanisms and the susceptibility of mtDNA to damage exacerbate the threat to human health. Heteroplasmy, the presence of different mtDNA genotypes within a single cell, increases the complexity of these diseases and requires an effective editing method for correction. Recently, gene-editing techniques, including programmable nucleases such as restriction endonuclease, zinc finger nuclease, transcription activator-like effector nuclease, clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeats-associated 9 and base editors, have provided new tools for editing mtDNA in mammalian cells. Base editors are particularly promising because of their high efficiency and precision in correcting mtDNA mutations. In this review, we discuss the application of these techniques in mitochondrial gene editing and their limitations. We also explore the potential of base editors for mtDNA modification and discuss the opportunities and challenges associated with their application in mitochondrial gene editing. In conclusion, this review highlights the advancements, limitations and opportunities in current mitochondrial gene-editing technologies and approaches. Our insights aim to stimulate the development of new editing strategies that can ultimately alleviate the adverse effects of mitochondrial hereditary diseases.
Collapse
Affiliation(s)
- Yanyan Gao
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Linlin Guo
- The Affiliated Cardiovascular Hospital of Qingdao University, Qingdao University, Qingdao, China
| | - Fei Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Yin Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Peifeng Li
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Dejiu Zhang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China.
| |
Collapse
|
3
|
Schultz A, Cheng SY, Kirchner E, Costello S, Miettinen H, Chaverra M, King C, George L, Zhao X, Narasimhan J, Weetall M, Slaugenhaupt S, Morini E, Punzo C, Lefcort F. Reduction of retinal ganglion cell death in mouse models of familial dysautonomia using AAV-mediated gene therapy and splicing modulators. Sci Rep 2023; 13:18600. [PMID: 37903840 PMCID: PMC10616160 DOI: 10.1038/s41598-023-45376-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Accepted: 10/18/2023] [Indexed: 11/01/2023] Open
Abstract
Familial dysautonomia (FD) is a rare neurodevelopmental and neurodegenerative disease caused by a splicing mutation in the Elongator Acetyltransferase Complex Subunit 1 (ELP1) gene. The reduction in ELP1 mRNA and protein leads to the death of retinal ganglion cells (RGCs) and visual impairment in all FD patients. Currently patient symptoms are managed, but there is no treatment for the disease. We sought to test the hypothesis that restoring levels of Elp1 would thwart the death of RGCs in FD. To this end, we tested the effectiveness of two therapeutic strategies for rescuing RGCs. Here we provide proof-of-concept data that gene replacement therapy and small molecule splicing modifiers effectively reduce the death of RGCs in mouse models for FD and provide pre-clinical foundational data for translation to FD patients.
Collapse
Affiliation(s)
- Anastasia Schultz
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA
| | - Shun-Yun Cheng
- Department of Ophthalmology, Neurobiology and Gene Therapy Center, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Emily Kirchner
- Center for Genomic Medicine, Massachusetts General Hospital Research Institute, Boston, MA, USA
| | - Stephanann Costello
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA
| | - Heini Miettinen
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA
| | - Marta Chaverra
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA
| | - Colin King
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA
| | - Lynn George
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA
- Department of Biological and Physical Science, Montana State University Billings, Billings, MT, USA
| | - Xin Zhao
- PTC Therapeutics, Inc., South Plainfield, NJ, 07080, USA
| | | | - Marla Weetall
- PTC Therapeutics, Inc., South Plainfield, NJ, 07080, USA
| | - Susan Slaugenhaupt
- Center for Genomic Medicine, Massachusetts General Hospital Research Institute, Boston, MA, USA
- Department of Neurology, Massachusetts General Hospital Research Institute and Harvard Medical School, Boston, MA, USA
| | - Elisabetta Morini
- Center for Genomic Medicine, Massachusetts General Hospital Research Institute, Boston, MA, USA
- Department of Neurology, Massachusetts General Hospital Research Institute and Harvard Medical School, Boston, MA, USA
| | - Claudio Punzo
- Department of Ophthalmology, Neurobiology and Gene Therapy Center, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Frances Lefcort
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA.
| |
Collapse
|
4
|
Hong S, Kim S, Kim K, Lee H. Clinical Approaches for Mitochondrial Diseases. Cells 2023; 12:2494. [PMID: 37887337 PMCID: PMC10605124 DOI: 10.3390/cells12202494] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 10/18/2023] [Accepted: 10/19/2023] [Indexed: 10/28/2023] Open
Abstract
Mitochondria are subcontractors dedicated to energy production within cells. In human mitochondria, almost all mitochondrial proteins originate from the nucleus, except for 13 subunit proteins that make up the crucial system required to perform 'oxidative phosphorylation (OX PHOS)', which are expressed by the mitochondria's self-contained DNA. Mitochondrial DNA (mtDNA) also encodes 2 rRNA and 22 tRNA species. Mitochondrial DNA replicates almost autonomously, independent of the nucleus, and its heredity follows a non-Mendelian pattern, exclusively passing from mother to children. Numerous studies have identified mtDNA mutation-related genetic diseases. The consequences of various types of mtDNA mutations, including insertions, deletions, and single base-pair mutations, are studied to reveal their relationship to mitochondrial diseases. Most mitochondrial diseases exhibit fatal symptoms, leading to ongoing therapeutic research with diverse approaches such as stimulating the defective OXPHOS system, mitochondrial replacement, and allotropic expression of defective enzymes. This review provides detailed information on two topics: (1) mitochondrial diseases caused by mtDNA mutations, and (2) the mechanisms of current treatments for mitochondrial diseases and clinical trials.
Collapse
Affiliation(s)
- Seongho Hong
- Korea Mouse Phenotyping Center, Seoul National University, Seoul 08826, Republic of Korea;
- Department of Medicine, Korea University College of Medicine, Seoul 02708, Republic of Korea
| | - Sanghun Kim
- Laboratory Animal Resource and Research Center, Korea Research Institute of Bioscience and Biotechnology, Cheongju 28116, Republic of Korea;
- College of Veterinary Medicine and Research Institute of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Republic of Korea
| | - Kyoungmi Kim
- Department of Biomedical Sciences, Korea University College of Medicine, Seoul 02841, Republic of Korea
- Department of Physiology, Korea University College of Medicine, Seoul 02841, Republic of Korea
| | - Hyunji Lee
- Department of Medicine, Korea University College of Medicine, Seoul 02708, Republic of Korea
| |
Collapse
|
5
|
Schultz A, Cheng SY, Kirchner E, Costello S, Miettinen H, Chaverra M, King C, George L, Zhao X, Narasimhan J, Weetall M, Slaugenhaupt S, Morini E, Punzo C, Lefcort F. Reduction of retinal ganglion cell death in mouse models of familial dysautonomia using AAV-mediated gene therapy and splicing modulators. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.22.541535. [PMID: 37293016 PMCID: PMC10245894 DOI: 10.1101/2023.05.22.541535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Familial dysautonomia (FD) is a rare neurodevelopmental and neurodegenerative disease caused by a splicing mutation in the Elongator Acetyltransferase Complex Subunit 1 ( ELP1 ) gene. The reduction in ELP1 mRNA and protein leads to the death of retinal ganglion cells (RGCs) and visual impairment in all FD patients. Currently, patient symptoms are managed, but there is no treatment for the disease. We sought to test the hypothesis that restoring levels of Elp1 would thwart the death of RGCs in FD. To this end, we tested the effectiveness of two therapeutic strategies for rescuing RGCs. Here we provide proof-of-concept data that gene replacement therapy and small molecule splicing modifiers effectively reduce the death of RGCs in mouse models for FD and provide pre-clinical data foundation for translation to FD patients.
Collapse
|
6
|
Velmurugan S, Chou TH, Eastwood JD, Porciatti V, Liu Y, Hauswirth WW, Guy J, Yu H. Comparison of different gene-therapy methods to treat Leber hereditary optic neuropathy in a mouse model. Front Neurosci 2023; 17:1119724. [PMID: 37051151 PMCID: PMC10083341 DOI: 10.3389/fnins.2023.1119724] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 01/13/2023] [Indexed: 03/28/2023] Open
Abstract
IntroductionTherapies for Leber hereditary optic neuropathy (LHON), in common with all disorders caused by mutated mitochondrial DNA, are inadequate. We have developed two gene therapy strategies for the disease: mitochondrial-targeted and allotopic expressed and compared them in a mouse model of LHON.MethodsA LHON mouse model was generated by intravitreal injection of a mitochondrialtargeted Adeno-associated virus (AAV) carrying mutant human NADH dehydrogenase 4 gene (hND4/m.11778G>A) to induce retinal ganglion cell (RGC) degeneration and axon loss, the hallmark of the human disease. We then attempted to rescue those mice using a second intravitreal injection of either mitochondrial-targeted or allotopic expressed wildtype human ND4. The rescue of RGCs and their axons were assessed using serial pattern electroretinogram (PERG) and transmission electron microscopy.ResultsCompared to non-rescued LHON controls where PERG amplitude was much reduced, both strategies significantly preserved PERG amplitude over 15 months. However, the rescue effect was more marked with mitochondrial-targeted therapy than with allotopic therapy (p = 0.0128). Post-mortem analysis showed that mitochondrial-targeted human ND4 better preserved small axons that are preferentially lost in human LHON.ConclusionsThese results in a pre-clinical mouse model of LHON suggest that mitochondrially-targeted AAV gene therapy, compared to allotopic AAV gene therapy, is more efficient in rescuing the LHON phenotype.
Collapse
Affiliation(s)
- Sindhu Velmurugan
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Tsung-Han Chou
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Jeremy D. Eastwood
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Vittorio Porciatti
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, United States
- *Correspondence: Vittorio Porciatti,
| | - Yuan Liu
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, United States
| | - William W. Hauswirth
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL, United States
| | - John Guy
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Hong Yu
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, United States
- Hong Yu,
| |
Collapse
|
7
|
Oxidative Stress in Antibiotic Toxic Optic Neuropathy Mimicking Acute LHON in a Patient with Exacerbation of Cystic Fibrosis. STRESSES 2023. [DOI: 10.3390/stresses3010028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/15/2023]
Abstract
The striking similarity of disc edema without leakage on fluorescein angiography, which is pathognomonic of Leber hereditary optic neuropathy (LHON), was present in a patient with cystic fibrosis with antibiotic toxic optic neuropathy. This similarity suggested the common effect of oxidative stress on retinal ganglion cells in inherited mitochondrial and antibiotic optic neuropathies. We present the case of a patient with advanced cystic fibrosis on chronic antibiotic treatment who experienced a rapid painless bilateral visual decline over a course of a few weeks. At examination, his corrected visual acuity was reduced to 0.3 in both eyes, with dyschromatopsia and central scotoma. The appearance of the fundus resembled the typical clinical features of acute LHON with hyperemic optic discs and tortuous vessels with no dye leakage from the optic discs on fluorescein angiography. Ganglion cell layer loss was seen on optic coherence tomography, with all findings pointing to LHON. Genetic testing did not reveal any LHON-specific mutations. After extended genetic testing, a heterozygous variant c.209C>T in the OPA3 gene on chromosome 19, g.46032648G>A, classified as a variant of unknown significance, was also found. After discontinuing antibiotics and general improvements in his health, surprisingly, his visual function completely improved. Later, he also received a bilateral lung transplant that further improved his general condition, and his vision remained normal. Excluding LHON, the transient optic neuropathy in our patient could be mainly due to antibiotic toxicity of linezolid and ciprofloxacin, which have been linked to mitochondrial dysfunction and advanced cystic fibrosis with hypoxic status. We suggest the possibility that patients with cystic fibrosis may be more prone to developing mitochondrial optic neuropathy, especially with additional risk factors such as chronic antibiotic therapy, which affect mitochondrial function, and can perhaps serve as a model for LHON.
Collapse
|
8
|
Saidia AR, Ruel J, Bahloul A, Chaix B, Venail F, Wang J. Current Advances in Gene Therapies of Genetic Auditory Neuropathy Spectrum Disorder. J Clin Med 2023; 12:jcm12030738. [PMID: 36769387 PMCID: PMC9918155 DOI: 10.3390/jcm12030738] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/11/2023] [Accepted: 01/13/2023] [Indexed: 01/18/2023] Open
Abstract
Auditory neuropathy spectrum disorder (ANSD) refers to a range of hearing impairments characterized by an impaired transmission of sound from the cochlea to the brain. This defect can be due to a lesion or defect in the inner hair cell (IHC), IHC ribbon synapse (e.g., pre-synaptic release of glutamate), postsynaptic terminals of the spiral ganglion neurons, or demyelination and axonal loss within the auditory nerve. To date, the only clinical treatment options for ANSD are hearing aids and cochlear implantation. However, despite the advances in hearing-aid and cochlear-implant technologies, the quality of perceived sound still cannot match that of the normal ear. Recent advanced genetic diagnostics and clinical audiology made it possible to identify the precise site of a lesion and to characterize the specific disease mechanisms of ANSD, thus bringing renewed hope to the treatment or prevention of auditory neurodegeneration. Moreover, genetic routes involving the replacement or corrective editing of mutant sequences or defected genes to repair damaged cells for the future restoration of hearing in deaf people are showing promise. In this review, we provide an update on recent discoveries in the molecular pathophysiology of genetic lesions, auditory synaptopathy and neuropathy, and gene-therapy research towards hearing restoration in rodent models and in clinical trials.
Collapse
Affiliation(s)
- Anissa Rym Saidia
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34295 Montpellier, France
| | - Jérôme Ruel
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34295 Montpellier, France
- Cognitive Neuroscience Laboratory, Aix-Marseille University, CNRS, UMR 7291, 13331 Marseille, France
| | - Amel Bahloul
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34295 Montpellier, France
| | - Benjamin Chaix
- Department of ENT and Head and Neck Surgery, University Hospital of Montpellier, 34295 Montpellier, France
| | - Frédéric Venail
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34295 Montpellier, France
- Department of ENT and Head and Neck Surgery, University Hospital of Montpellier, 34295 Montpellier, France
| | - Jing Wang
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34295 Montpellier, France
- Department of ENT and Head and Neck Surgery, University Hospital of Montpellier, 34295 Montpellier, France
- Correspondence: ; Tel.: +33-499-63-60-48
| |
Collapse
|
9
|
Bernstein SL, Guo Y, Mehrabian Z, Miller NR. Neuroprotection and Neuroregeneration Strategies Using the rNAION Model: Theory, Histology, Problems, Results and Analytical Approaches. Int J Mol Sci 2022; 23:ijms232415604. [PMID: 36555246 PMCID: PMC9778957 DOI: 10.3390/ijms232415604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/18/2022] [Accepted: 11/23/2022] [Indexed: 12/13/2022] Open
Abstract
Nonarteritic anterior ischemic optic neuropathy (NAION) is the most common cause of sudden optic nerve (ON)-related vision loss in humans. Study of this disease has been limited by the lack of available tissue and difficulties in evaluating both treatments and the window of effectiveness after symptom onset. The rodent nonarteritic anterior ischemic optic neuropathy model (rNAION) closely resembles clinical NAION in its pathophysiological changes and physiological responses. The rNAION model enables analysis of the specific responses to sudden ischemic axonopathy and effectiveness of potential treatments. However, there are anatomic and genetic differences between human and rodent ON, and the inducing factors for the disease and the model are different. These variables can result in marked differences in lesion development between the two species, as well as in the possible responses to various treatments. These caveats are discussed in the current article, as well as some of the species-associated differences that may be related to ischemic lesion severity and responses.
Collapse
Affiliation(s)
- Steven L. Bernstein
- Department of Ophthalmology and Visual Sciences, University of Maryland at Baltimore School of Medicine, 10 S. Pine St., Baltimore, MD 21201, USA
- Department of Anatomy and Neurobiology, University of Maryland at Baltimore School of Medicine, 10 S. Pine St., Baltimore, MD 21201, USA
- Correspondence: ; Tel.: +1-410-706-3712
| | - Yan Guo
- Department of Ophthalmology and Visual Sciences, University of Maryland at Baltimore School of Medicine, 10 S. Pine St., Baltimore, MD 21201, USA
| | - Zara Mehrabian
- Department of Ophthalmology and Visual Sciences, University of Maryland at Baltimore School of Medicine, 10 S. Pine St., Baltimore, MD 21201, USA
| | - Neil R. Miller
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, 600 N. Wolfe St., Baltimore, MD 21205, USA
| |
Collapse
|
10
|
Newman NJ, Yu-Wai-Man P, Subramanian PS, Moster ML, Wang AG, Donahue SP, Leroy BP, Carelli V, Biousse V, Vignal-Clermont C, Sergott RC, Sadun AA, Fernández GR, Chwalisz BK, Banik R, Bazin F, Roux M, Cox ED, Taiel M, Sahel JA. Randomized trial of bilateral gene therapy injection for m.11778G > A MT-ND4 Leber optic neuropathy. Brain 2022; 146:1328-1341. [PMID: 36350566 PMCID: PMC10115230 DOI: 10.1093/brain/awac421] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 09/20/2022] [Accepted: 10/02/2022] [Indexed: 11/11/2022] Open
Abstract
Leber hereditary optic neuropathy (LHON) is an important example of mitochondrial blindness with the m.11778G > A mutation in the MT-ND4 gene being the most common disease-causing mitochondrial DNA (mtDNA) variant worldwide. The REFLECT phase 3 pivotal study is a randomized, double-masked, placebo-controlled trial investigating the efficacy and safety of bilateral intravitreal injection of lenadogene nolparvovec in patients with a confirmed m.11778G > A mutation, using a recombinant adeno-associated virus vector 2, serotype 2 (rAAV2/2-ND4). The first-affected eye received gene therapy; the fellow (affected/not-yet-affected) eye was randomly injected with gene therapy or placebo. The primary endpoint was the difference in change from baseline of best-corrected visual acuity (BCVA) in second-affected/not-yet-affected eyes treated with lenadogene nolparvovec versus placebo at 1.5 years post-treatment, expressed in logarithm of the minimal angle of resolution (LogMAR). Forty-eight patients were treated bilaterally and 50 unilaterally. At 1.5 years, the change from baseline in BCVA was not statistically different between second-affected/not-yet-affected eyes receiving lenadogene nolparvovec and placebo (primary endpoint). A statistically significant improvement in BCVA was reported from baseline to 1.5 years in lenadogene nolparvovec-treated eyes: -0.23 LogMAR for the first-affected eyes of bilaterally treated patients (p < 0.01); and -0.15 LogMAR for second-affected/not-yet-affected eyes of bilaterally treated patients and the first-affected eyes of unilaterally treated patients (p < 0.05). The mean improvement in BCVA from nadir to 1.5 years was -0.38 (0.052) LogMAR and -0.33 (0.052) LogMAR in first-affected and second-affected/not-yet-affected eyes treated with lenadogene nolparvovec, respectively (bilateral treatment group). A mean improvement of -0.33 (0.051) LogMAR and -0.26 (0.051) LogMAR was observed in first-affected lenadogene nolparvovec-treated eyes and second-affected/not-yet-affected placebo-treated eyes, respectively (unilateral treatment group). The proportion of patients with one or both eyes on-chart at 1.5 years was 85.4% and 72.0% for bilaterally and unilaterally treated patients, respectively. The gene therapy was well tolerated, with no systemic issues. Intraocular inflammation, which was mostly mild and well controlled with topical corticosteroids, occurred in 70.7% of lenadogene nolparvovec-treated eyes versus 10.2% of placebo-treated eyes. Among eyes treated with lenadogene nolparvovec, there was no difference in the incidence of intraocular inflammation between bilaterally and unilaterally treated patients. Overall, the REFLECT trial demonstrated an improvement of BCVA in LHON eyes carrying the m.11778G > A mtDNA mutation treated with lenadogene nolparvovec or placebo to a degree not reported in natural history studies and supports an improved benefit/risk profile for bilateral injections of lenadogene nolparvovec relative to unilateral injections.
Collapse
Affiliation(s)
- Nancy J Newman
- Departments of Ophthalmology, Neurology and Neurological Surgery, Emory University School of Medicine, Atlanta, GA, USA
| | - Patrick Yu-Wai-Man
- Cambridge Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, UK
- Moorfields Eye Hospital, London, UK
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Prem S Subramanian
- Sue Anschutz-Rodgers University of Colorado Eye Center, University of Colorado School of Medicine, Aurora, CO, USA
| | - Mark L Moster
- Departments of Neurology and Ophthalmology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, PA, USA
| | - An-Guor Wang
- Department of Ophthalmology, Taipei Veterans General Hospital, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Sean P Donahue
- Department of Ophthalmology, Neurology, and Pediatrics, Vanderbilt University, and Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Bart P Leroy
- Department of Ophthalmology and Center for Medical Genetics, Ghent University Hospital, and Department of Head & Skin, Ghent University, Ghent, Belgium
| | - Valerio Carelli
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Programma di Neurogenetica, Bologna, Italy
- Unit of Neurology, Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Valerie Biousse
- Departments of Ophthalmology, Neurology and Neurological Surgery, Emory University School of Medicine, Atlanta, GA, USA
| | - Catherine Vignal-Clermont
- Department of Neuro Ophthalmology and Emergencies, Rothschild Foundation Hospital, Paris, France
- Centre Hospitalier National D'Ophtalmologie des Quinze Vingts, Paris, France
| | - Robert C Sergott
- Departments of Neurology and Ophthalmology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, PA, USA
| | - Alfredo A Sadun
- Doheny Eye Institute, UCLA School of Medicine, Los Angeles, CA, USA
| | | | - Bart K Chwalisz
- Department of Ophthalmology, Massachusetts Eye & Ear, Harvard Medical School, Boston, MA, USA
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston MA, USA
| | - Rudrani Banik
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | | | | | | | - José-Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
- Fondation Ophtalmologique A. de Rothschild, Paris, France
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- CHNO des Quinze-Vingts, Institut Hospitalo-Universitaire FOReSIGHT, INSERM-DGOS CIC, Paris, France
| | | |
Collapse
|
11
|
Traitements médicaux dans la neuropathie optique héréditaire de Leber. J Fr Ophtalmol 2022; 45:S24-S31. [DOI: 10.1016/s0181-5512(22)00447-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
12
|
Chen BS, Yu-Wai-Man P. From Bench to Bedside-Delivering Gene Therapy for Leber Hereditary Optic Neuropathy. Cold Spring Harb Perspect Med 2022; 12:a041282. [PMID: 35863905 PMCID: PMC9310952 DOI: 10.1101/cshperspect.a041282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Leber hereditary optic neuropathy (LHON) is a rare, maternally inherited mitochondrial disorder that presents with severe bilateral sequential vision loss, due to the selective degeneration of retinal ganglion cells (RGCs). Since the mitochondrial genetic basis for LHON was uncovered in 1988, considerable progress has been made in understanding the pathogenetic mechanisms driving RGC loss, which has enabled the development of therapeutic approaches aimed at mitigating the underlying mitochondrial dysfunction. In this review, we explore the genetics of LHON, from bench to bedside, focusing on the pathogenetic mechanisms and how these have informed the development of different gene therapy approaches, in particular the technique of allotopic expression with adeno-associated viral vectors. Finally, we provide an overview of the recent gene therapy clinical trials and consider the unanswered questions, challenges, and future prospects.
Collapse
Affiliation(s)
- Benson S Chen
- John van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0PY, United Kingdom
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge CB2 0QQ, United Kingdom
| | - Patrick Yu-Wai-Man
- John van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0PY, United Kingdom
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge CB2 0QQ, United Kingdom
- Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, United Kingdom
- Institute of Ophthalmology, University College London, London EC1V 9EL, United Kingdom
| |
Collapse
|
13
|
Newman NJ, Schniederjan M, Mendoza PR, Calkins DJ, Yu-Wai-Man P, Biousse V, Carelli V, Taiel M, Rugiero F, Singh P, Rogue A, Sahel JA, Ancian P. Absence of lenadogene nolparvovec DNA in a brain tumor biopsy from a patient in the REVERSE clinical study, a case report. BMC Neurol 2022; 22:257. [PMID: 35820885 PMCID: PMC9277876 DOI: 10.1186/s12883-022-02787-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 07/06/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Leber Hereditary Optic Neuropathy (LHON) is a rare, maternally-inherited mitochondrial disease that primarily affects retinal ganglion cells (RGCs) and their axons in the optic nerve, leading to irreversible, bilateral severe vision loss. Lenadogene nolparvovec gene therapy was developed as a treatment for patients with vision loss from LHON caused by the most prevalent m.11778G > A mitochondrial DNA point mutation in the MT-ND4 gene. Lenadogene nolparvovec is a replication-defective recombinant adeno-associated virus vector 2 serotype 2 (AAV2/2), encoding the human wild-type MT-ND4 protein. Lenadogene nolparvovec was administered by intravitreal injection (IVT) in LHON patients harboring the m.11778G > A ND4 mutation in a clinical development program including one phase 1/2 study (REVEAL), three phase 3 pivotal studies (REVERSE, RESCUE, REFLECT), and one long-term follow-up study (RESTORE, the follow-up of REVERSE and RESCUE patients). CASE PRESENTATION A 67-year-old woman with MT-ND4 LHON, included in the REVERSE clinical study, received a unilateral IVT of lenadogene nolparvovec in the right eye and a sham injection in the left eye in May 2016, 11.4 months and 8.8 months after vision loss in her right and left eyes, respectively. The patient had a normal brain magnetic resonance imaging with contrast at the time of diagnosis of LHON. Two years after treatment administration, BCVA had improved in both eyes. The product was well tolerated with mild and resolutive anterior chamber inflammation in the treated eye. In May 2019, the patient was diagnosed with a right temporal lobe glioblastoma, IDH-wildtype, World Health Organization grade 4, based on histological analysis of a tumor excision. The brain tumor was assessed for the presence of vector DNA by using a sensitive validated qPCR assay targeting the ND4 sequence of the vector. CONCLUSION ND4 DNA was not detected (below 15.625 copies/μg of genomic DNA) in DNA extracted from the brain tumor, while a housekeeping gene DNA was detected at high levels. Taken together, this data shows the absence of detection of lenadogene nolparvovec in a brain tumor (glioblastoma) of a treated patient in the REVERSE clinical trial 3 years after gene therapy administration, supporting the long-term favorable safety of lenadogene nolparvovec.
Collapse
Affiliation(s)
- Nancy J Newman
- Departments of Ophthalmology, Neurology and Neurological Surgery, Neuro-Ophthalmology Unit, Emory Eye Center, Emory University School of Medicine, 1365-B Clifton Road NE, Atlanta, GA, 30322, USA.
| | - Matthew Schniederjan
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA, USA
| | - Pia R Mendoza
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA, USA
| | - David J Calkins
- Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, 1161 21st Avenue South, Nashville, TN, 37232, USA
| | - Patrick Yu-Wai-Man
- Cambridge Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, UK
- Moorfields Eye Hospital, London, UK
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Valérie Biousse
- Departments of Ophthalmology, Neurology and Neurological Surgery, Neuro-Ophthalmology Unit, Emory Eye Center, Emory University School of Medicine, 1365-B Clifton Road NE, Atlanta, GA, 30322, USA
| | - Valerio Carelli
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOC Clinica Neurologica, Bologna, Italy
- Unit of Neurology, Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Magali Taiel
- GenSight Biologics, 74 rue du Faubourg Saint Antoine, 75012, Paris, France
| | | | | | | | - José-Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
- Fondation Ophtalmologique A. de Rothschild, Paris, France
- Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- CHNO des Quinze-Vingts, Institut Hospitalo-Universitaire FOReSIGHT, INSERM-DGOS CIC, Paris, France
| | | |
Collapse
|
14
|
Gene Therapy for Mitochondrial Diseases: Current Status and Future Perspective. Pharmaceutics 2022; 14:pharmaceutics14061287. [PMID: 35745859 PMCID: PMC9231068 DOI: 10.3390/pharmaceutics14061287] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 06/09/2022] [Accepted: 06/15/2022] [Indexed: 02/06/2023] Open
Abstract
Mitochondrial diseases (MDs) are a group of severe genetic disorders caused by mutations in the nuclear or mitochondrial genome encoding proteins involved in the oxidative phosphorylation (OXPHOS) system. MDs have a wide range of symptoms, ranging from organ-specific to multisystemic dysfunctions, with different clinical outcomes. The lack of natural history information, the limits of currently available preclinical models, and the wide range of phenotypic presentations seen in MD patients have all hampered the development of effective therapies. The growing number of pre-clinical and clinical trials over the last decade has shown that gene therapy is a viable precision medicine option for treating MD. However, several obstacles must be overcome, including vector design, targeted tissue tropism and efficient delivery, transgene expression, and immunotoxicity. This manuscript offers a comprehensive overview of the state of the art of gene therapy in MD, addressing the main challenges, the most feasible solutions, and the future perspectives of the field.
Collapse
|
15
|
Gene therapy restores mitochondrial function and protects retinal ganglion cells in optic neuropathy induced by a mito-targeted mutant ND1 gene. Gene Ther 2022; 29:368-378. [PMID: 35383288 PMCID: PMC9233058 DOI: 10.1038/s41434-022-00333-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 03/19/2022] [Accepted: 03/24/2022] [Indexed: 11/21/2022]
Abstract
Therapies for genetic disorders caused by mutated mitochondrial DNA are an unmet need, in large part due barriers in delivering DNA to the organelle and the absence of relevant animal models. We injected into mouse eyes a mitochondrially targeted Adeno-Associated-Virus (MTS-AAV) to deliver the mutant human NADH ubiquinone oxidoreductase subunit I (hND1/m.3460G>A) responsible for Leber’s hereditary optic neuropathy, the most common primary mitochondrial genetic disease. We show that the expression of the mutant hND1 delivered to retinal ganglion cells (RGC) layer colocalizes with the mitochondrial marker PORIN and the assembly of the expressed hND1 protein into host respiration complex I. The hND1 injected eyes exhibit hallmarks of the human disease with progressive loss of RGC function and number, as well as optic nerve degeneration. We also show that gene therapy in the hND1 eyes by means of an injection of a second MTS-AAV vector carrying wild type human ND1 restores mitochondrial respiratory complex I activity, the rate of ATP synthesis and protects RGCs and their axons from dysfunction and degeneration. These results prove that MTS-AAV is a highly efficient gene delivery approach with the ability to create mito-animal models and has the therapeutic potential to treat mitochondrial genetic diseases.
Collapse
|
16
|
Siedlecki J, Koenig S, Catarino C, Schaumberger MM, Schworm B, Priglinger SG, Rudolph G, von Livonius B, Klopstock T, Priglinger CS. Childhood versus early-teenage onset Leber's hereditary optic neuropathy: visual prognosis and capacity for recovery. Br J Ophthalmol 2022:bjophthalmol-2021-320580. [PMID: 35190400 DOI: 10.1136/bjophthalmol-2021-320580] [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: 10/21/2021] [Accepted: 01/22/2022] [Indexed: 11/03/2022]
Abstract
OBJECTIVE In Leber's hereditary optic neuropathy (LHON) in children and teenagers, the influence of age on visual prognosis has not yet been investigated. METHODS Patients from the mitoNET registry with LHON onset at age 4-16 years with at least 4 years of follow-up without treatment were included. Visual acuity (VA) at baseline, lowest VA ever recorded (nadir) and VA at end of follow-up were compared between childhood onset (ChO, ≤12 years of age) and early-teenage onset (eTO; 13-16 years). RESULTS Out of 231 patients with LHON, 19 met the inclusion criteria (8.2%). There were 11 patients in the ChO and 8 patients in the eTO group. Mean age at onset was 8.6 (SD 2.1) years (ChO) and 15.4 (SD 0.7) years (eTO) (p<0.00001). Follow-up was mean 184 (SD 129) months (ChO) and 119 (SD 78) months (eTO) (p=0.22). Baseline VA was similar between both groups in better (p=0.96) and worse eyes (p=0.54). In worse eyes, both groups deteriorated similarly (p=0.79) until nadir and showed similar recovery until end of follow-up (p=0.38). In better eyes, both groups deteriorated similarly (p=0.16) until nadir. From nadir until end of follow-up, better eyes in the ChO group showed a significantly better recovery (-0.35 (SD 0.36) vs -0.01 (SD 0.06) logMAR; p=0.02) than eTO eyes. CONCLUSION Visual prognosis of LHON in children is much more favourable in cases of childhood onset (≤12 years of age) as compared with teenage onset (13-16 years), mostly due to better recovery from nadir in childhood onset.
Collapse
Affiliation(s)
- Jakob Siedlecki
- Department of Ophthalmology, Ludwig-Maximilians-Universität München, Munchen, Bayern, Germany
| | - Susanna Koenig
- Department of Ophthalmology, Ludwig-Maximilians-Universität München, Munchen, Bayern, Germany
| | - Claudia Catarino
- Friedrich-Baur-Institut, Neurologische Klinik und Poliklinik, Ludwig-Maximilians-Universität München, Munchen, Bayern, Germany
| | - Markus M Schaumberger
- Department of Ophthalmology, Ludwig-Maximilians-Universität München, Munchen, Bayern, Germany
| | - Benedikt Schworm
- Department of Ophthalmology, Ludwig-Maximilians-Universität München, Munchen, Bayern, Germany
| | | | - Guenther Rudolph
- Department of Ophthalmology, Ludwig-Maximilians-Universität München, Munchen, Bayern, Germany
| | - Bettina von Livonius
- Department of Ophthalmology, Ludwig-Maximilians-Universität München, Munchen, Bayern, Germany
| | - Thomas Klopstock
- Friedrich-Baur-Institut, Neurologische Klinik und Poliklinik, Ludwig-Maximilians-Universität München, Munchen, Bayern, Germany
| | - Claudia S Priglinger
- Department of Ophthalmology, Ludwig-Maximilians-Universität München, Munchen, Bayern, Germany
| |
Collapse
|
17
|
The Mitochondrial Genome in Aging and Disease and the Future of Mitochondrial Therapeutics. Biomedicines 2022; 10:biomedicines10020490. [PMID: 35203698 PMCID: PMC8962324 DOI: 10.3390/biomedicines10020490] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 02/10/2022] [Accepted: 02/16/2022] [Indexed: 11/29/2022] Open
Abstract
Mitochondria are intracellular organelles that utilize nutrients to generate energy in the form of ATP by oxidative phosphorylation. Mitochondrial DNA (mtDNA) in humans is a 16,569 base pair double-stranded circular DNA that encodes for 13 vital proteins of the electron transport chain. Our understanding of the mitochondrial genome’s transcription, translation, and maintenance is still emerging, and human pathologies caused by mtDNA dysfunction are widely observed. Additionally, a correlation between declining mitochondrial DNA quality and copy number with organelle dysfunction in aging is well-documented in the literature. Despite tremendous advancements in nuclear gene-editing technologies and their value in translational avenues, our ability to edit mitochondrial DNA is still limited. In this review, we discuss the current therapeutic landscape in addressing the various pathologies that result from mtDNA mutations. We further evaluate existing gene therapy efforts, particularly allotopic expression and its potential to become an indispensable tool for restoring mitochondrial health in disease and aging.
Collapse
|
18
|
Chow-Wing-Bom HT, Callaghan MF, Wang J, Wei S, Dick F, Yu-Wai-Man P, Dekker TM. Neuroimaging in Leber Hereditary Optic Neuropathy: State-of-the-art and future prospects. Neuroimage Clin 2022; 36:103240. [PMID: 36510411 PMCID: PMC9668671 DOI: 10.1016/j.nicl.2022.103240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 06/14/2022] [Accepted: 10/17/2022] [Indexed: 11/05/2022]
Abstract
Leber Hereditary Optic Neuropathy (LHON) is an inherited mitochondrial retinal disease that causes the degeneration of retinal ganglion cells and leads to drastic loss of visual function. In the last decades, there has been a growing interest in using Magnetic Resonance Imaging (MRI) to better understand mechanisms of LHON beyond the retina. This is partially due to the emergence of gene-therapies for retinal diseases, and the accompanying expanded need for reliably quantifying and monitoring visual processing and treatment efficiency in patient populations. This paper aims to draw a current picture of key findings in this field so far, the challenges of using neuroimaging methods in patients with LHON, and important open questions that MRI can help address about LHON disease mechanisms and prognoses, including how downstream visual brain regions are affected by the disease and treatment and why, and how scope for neural plasticity in these pathways may limit or facilitate recovery.
Collapse
Affiliation(s)
- Hugo T Chow-Wing-Bom
- Institute of Ophthalmology, University College London (UCL), London, United Kingdom; Birkbeck/UCL Centre for NeuroImaging, London, United Kingdom.
| | - Martina F Callaghan
- Wellcome Centre for Human Neuroimaging, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Junqing Wang
- Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, The Chinese People's Liberation Army Medical School, Beijing, China
| | - Shihui Wei
- Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, The Chinese People's Liberation Army Medical School, Beijing, China
| | - Frederic Dick
- Birkbeck/UCL Centre for NeuroImaging, London, United Kingdom; Department of Psychological Sciences, Birkbeck, University of London, United Kingdom; Department of Experimental Psychology, UCL, London, United Kingdom
| | - Patrick Yu-Wai-Man
- Institute of Ophthalmology, University College London (UCL), London, United Kingdom; John van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom; Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, United Kingdom; Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
| | - Tessa M Dekker
- Institute of Ophthalmology, University College London (UCL), London, United Kingdom; Birkbeck/UCL Centre for NeuroImaging, London, United Kingdom; Department of Experimental Psychology, UCL, London, United Kingdom
| |
Collapse
|
19
|
Calkins DJ, Yu-Wai-Man P, Newman NJ, Taiel M, Singh P, Chalmey C, Rogue A, Carelli V, Ancian P, Sahel JA. Biodistribution of intravitreal lenadogene nolparvovec gene therapy in nonhuman primates. Mol Ther Methods Clin Dev 2021; 23:307-318. [PMID: 34729378 PMCID: PMC8526752 DOI: 10.1016/j.omtm.2021.09.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 09/24/2021] [Indexed: 11/25/2022]
Abstract
Lenadogene nolparvovec (Lumevoq) gene therapy was developed to treat Leber hereditary optic neuropathy (LHON) caused by the m.11778G > A in MT-ND4 that affects complex I of the mitochondrial respiratory chain. Lenadogene nolparvovec is a replication-defective, single-stranded DNA recombinant adeno-associated virus vector 2 serotype 2, containing a codon-optimized complementary DNA encoding the human wild-type MT-ND4 subunit protein. Lenadogene nolparvovec was administered by unilateral intravitreal injection in MT-ND4 LHON patients in two randomized, double-masked, and sham-controlled phase III clinical trials (REVERSE and RESCUE), resulting in bilateral improvement of visual acuity. These and other earlier results suggest that lenadogene nolparvovec may travel from the treated to the untreated eye. To investigate this possibility further, lenadogene nolparvovec was unilaterally injected into the vitreous body of the right eye of healthy, nonhuman primates. Viral vector DNA was quantifiable in all eye and optic nerve tissues of the injected eye and was detected at lower levels in some tissues of the contralateral, noninjected eye, and optic projections, at 3 and 6 months after injection. The results suggest that lenadogene nolparvovec transfers from the injected to the noninjected eye, thus providing a potential explanation for the bilateral improvement of visual function observed in the LHON patients.
Collapse
Affiliation(s)
- David J. Calkins
- Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, 1161 21st Avenue South, Nashville, TN 37232, USA
| | - Patrick Yu-Wai-Man
- Cambridge Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- Cambridge Eye Unit, Addenbrooke’s Hospital, Cambridge University Hospitals, Cambridge, UK
- Moorfields Eye Hospital, London, UK
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Nancy J. Newman
- Departments of Ophthalmology, Neurology, and Neurological Surgery, Emory University School of Medicine, Atlanta, GA, USA
| | - Magali Taiel
- GenSight Biologics, 74 rue du Faubourg Saint Antoine, 75012 Paris, France
| | | | | | | | - Valerio Carelli
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOC Clinica, Neurologica, Bologna, Italy
- Unit of Neurology, Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | | | - José A. Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
- Fondation Ophtalmologique A. de Rothschild, Paris, France
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- CHNO des Quinze-Vingts, Institut Hospitalo-Universitaire FOReSIGHT, INSERM-DGOS CIC, Paris, France
| |
Collapse
|
20
|
Sahel JA, Newman NJ, Yu-Wai-Man P, Vignal-Clermont C, Carelli V, Biousse V, Moster ML, Sergott R, Klopstock T, Sadun AA, Blouin L, Katz B, Taiel M. Gene Therapies for the Treatment of Leber Hereditary Optic Neuropathy. Int Ophthalmol Clin 2021; 61:195-208. [PMID: 34584057 PMCID: PMC8478322 DOI: 10.1097/iio.0000000000000364] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
21
|
Wang Y, Hu LF, Cui PF, Qi LY, Xing L, Jiang HL. Pathologically Responsive Mitochondrial Gene Therapy in an Allotopic Expression-Independent Manner Cures Leber's Hereditary Optic Neuropathy. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2103307. [PMID: 34431574 DOI: 10.1002/adma.202103307] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/20/2021] [Indexed: 06/13/2023]
Abstract
Leber's hereditary optic neuropathy (LHON) is a rare inherited blindness caused by mutations in the mitochondrial DNA (mtDNA). The disorder is untreatable and tricky, as the existing chemotherapeutic agent Idebenone alleviates symptoms rather than overcoming the underlying cause. Although some studies have made progress on allotopic expression for LHON, in situ mitochondrial gene therapy remains challenging, which may simplify delivery procedures to be a promising therapeutic for LHON. LHON becomes more difficult to manage in the changed mitochondrial microenvironment, including increasing reactive oxygen species (ROS) and decreasing mitochondrial membrane potential (MMP). Herein, a pathologically responsive mitochondrial gene delivery vector named [triphenylphosphine-terminated poly(sulfur-containing thioketal undecafluorohexylamine histamine) and Ide-terminated poly(sulfur-containing thioketal undecafluorohexylamine histamine)] (TISUH) is reported to facilitate commendable in situ mitochondrial gene therapy for LHON. TISUH directly targets diseased mitochondria via triphenylphosphine and fluorination addressing the decreasing MMP. In addition, TISUH can be disassembled by high mitochondrial ROS levels to release functional genes for enhancing gene transfection efficiency and fundamentally correcting genetic abnormalities. In both traditional and gene-mutation-induced LHON mouse models, TISUH-mediated gene therapy shows satisfactory curative effect through the sustained therapeutic protein expression in vivo. This work proposes a novel pathologically responsive in situ mitochondrial delivery platform and provides a promising approach for refractory LHON as well as other mtDNA mutated diseases treatments.
Collapse
Affiliation(s)
- Yi Wang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, China
| | - Li-Fan Hu
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, China
| | - Peng-Fei Cui
- School of Pharmacy, Changzhou University, Changzhou, 213164, China
| | - Lian-Yu Qi
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, China
| | - Lei Xing
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, China
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, China Pharmaceutical University, Nanjing, 210009, China
- Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, China Pharmaceutical University, Nanjing, 210009, China
| | - Hu-Lin Jiang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, China
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, China Pharmaceutical University, Nanjing, 210009, China
- Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, China Pharmaceutical University, Nanjing, 210009, China
| |
Collapse
|
22
|
Yu-Wai-Man P, Newman NJ, Carelli V, Moster ML, Biousse V, Sadun AA, Klopstock T, Vignal-Clermont C, Sergott RC, Rudolph G, La Morgia C, Karanjia R, Taiel M, Blouin L, Burguière P, Smits G, Chevalier C, Masonson H, Salermo Y, Katz B, Picaud S, Calkins DJ, Sahel JA. Bilateral visual improvement with unilateral gene therapy injection for Leber hereditary optic neuropathy. Sci Transl Med 2021; 12:12/573/eaaz7423. [PMID: 33298565 DOI: 10.1126/scitranslmed.aaz7423] [Citation(s) in RCA: 103] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Revised: 03/17/2020] [Accepted: 09/02/2020] [Indexed: 12/14/2022]
Abstract
REVERSE is a randomized, double-masked, sham-controlled, multicenter, phase 3 clinical trial that evaluated the efficacy of a single intravitreal injection of rAAV2/2-ND4 in subjects with visual loss from Leber hereditary optic neuropathy (LHON). A total of 37 subjects carrying the m.11778G>A (MT-ND4) mutation and with duration of vision loss between 6 to 12 months were treated. Each subject's right eye was randomly assigned in a 1:1 ratio to treatment with rAAV2/2-ND4 (GS010) or sham injection. The left eye received the treatment not allocated to the right eye. Unexpectedly, sustained visual improvement was observed in both eyes over the 96-week follow-up period. At week 96, rAAV2/2-ND4-treated eyes showed a mean improvement in best-corrected visual acuity (BCVA) of -0.308 LogMAR (+15 ETDRS letters). A mean improvement of -0.259 LogMAR (+13 ETDRS letters) was observed in the sham-treated eyes. Consequently, the primary end point, defined as the difference in the change in BCVA from baseline to week 48 between the two treatment groups, was not met (P = 0.894). At week 96, 25 subjects (68%) had a clinically relevant recovery in BCVA from baseline in at least one eye, and 29 subjects (78%) had an improvement in vision in both eyes. A nonhuman primate study was conducted to investigate this bilateral improvement. Evidence of transfer of viral vector DNA from the injected eye to the anterior segment, retina, and optic nerve of the contralateral noninjected eye supports a plausible mechanistic explanation for the unexpected bilateral improvement in visual function after unilateral injection.
Collapse
Affiliation(s)
- Patrick Yu-Wai-Man
- Cambridge Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0PY, UK. .,Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge CB2 0QQ, UK.,Moorfields Eye Hospital, London EC1V 2PD, UK.,UCL Institute of Ophthalmology, University College London, London EC1V 9EL, UK
| | - Nancy J Newman
- Departments of Ophthalmology, Neurology and Neurological Surgery, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Valerio Carelli
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOC Clinica Neurologica, 40139 Bologna, Italy.,Unit of Neurology, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, 40139 Bologna, Italy
| | - Mark L Moster
- Departments of Neurology and Ophthalmology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Valerie Biousse
- Departments of Ophthalmology, Neurology and Neurological Surgery, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Alfredo A Sadun
- Doheny Eye Institute and UCLA School of Medicine, Los Angeles, CA 90086, USA
| | - Thomas Klopstock
- Friedrich Baur Institute at the Department of Neurology, University Hospital, LMU Munich, 80336 Munich, Germany.,German Center for Neurodegenerative Diseases (DZNE), 80336 Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), 80336 Munich, Germany
| | - Catherine Vignal-Clermont
- Department of Neuro-Ophthalmology and Emergencies, Rothschild Foundation Hospital, 75019 Paris, France.,Centre Hospitalier National d'Ophtalmologie des Quinze Vingts, FOReSIGHT, INSERM-DGOS CIC 1423, 75012 Paris, France
| | - Robert C Sergott
- Departments of Neurology and Ophthalmology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Günther Rudolph
- Department of Ophthalmology, University Hospital, LMU Munich, 80336 Munich, Germany
| | - Chiara La Morgia
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOC Clinica Neurologica, 40139 Bologna, Italy.,Unit of Neurology, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, 40139 Bologna, Italy
| | - Rustum Karanjia
- Doheny Eye Institute and UCLA School of Medicine, Los Angeles, CA 90086, USA.,Ottawa Hospital Research Institute and University of Ottawa Eye Institute, Ottawa, Ontario K1H 8L6, Canada
| | | | | | | | | | | | | | | | | | - Serge Picaud
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 75012 Paris, France
| | - David J Calkins
- The Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - José-Alain Sahel
- Centre Hospitalier National d'Ophtalmologie des Quinze Vingts, FOReSIGHT, INSERM-DGOS CIC 1423, 75012 Paris, France. .,Sorbonne Université, INSERM, CNRS, Institut de la Vision, 75012 Paris, France.,Fondation Ophtalmologique A. de Rothschild, 25-29 Rue Manin, 75019 Paris, France.,Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| |
Collapse
|
23
|
Rossmann MP, Dubois SM, Agarwal S, Zon LI. Mitochondrial function in development and disease. Dis Model Mech 2021; 14:269120. [PMID: 34114603 PMCID: PMC8214736 DOI: 10.1242/dmm.048912] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Mitochondria are organelles with vital functions in almost all eukaryotic cells. Often described as the cellular ‘powerhouses’ due to their essential role in aerobic oxidative phosphorylation, mitochondria perform many other essential functions beyond energy production. As signaling organelles, mitochondria communicate with the nucleus and other organelles to help maintain cellular homeostasis, allow cellular adaptation to diverse stresses, and help steer cell fate decisions during development. Mitochondria have taken center stage in the research of normal and pathological processes, including normal tissue homeostasis and metabolism, neurodegeneration, immunity and infectious diseases. The central role that mitochondria assume within cells is evidenced by the broad impact of mitochondrial diseases, caused by defects in either mitochondrial or nuclear genes encoding for mitochondrial proteins, on different organ systems. In this Review, we will provide the reader with a foundation of the mitochondrial ‘hardware’, the mitochondrion itself, with its specific dynamics, quality control mechanisms and cross-organelle communication, including its roles as a driver of an innate immune response, all with a focus on development, disease and aging. We will further discuss how mitochondrial DNA is inherited, how its mutation affects cell and organismal fitness, and current therapeutic approaches for mitochondrial diseases in both model organisms and humans. Summary: Mitochondria have a plethora of functions beyond metabolism. This Review discusses the emerging and multifaceted roles of mitochondria in different model organisms and human disease biology.
Collapse
Affiliation(s)
- Marlies P Rossmann
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 01238, USA.,Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Howard Hughes Medical Institute, Boston, MA 02115, USA
| | - Sonia M Dubois
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Suneet Agarwal
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Leonard I Zon
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 01238, USA.,Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Howard Hughes Medical Institute, Boston, MA 02115, USA
| |
Collapse
|
24
|
Hage R, Vignal-Clermont C. Leber Hereditary Optic Neuropathy: Review of Treatment and Management. Front Neurol 2021; 12:651639. [PMID: 34122299 PMCID: PMC8187781 DOI: 10.3389/fneur.2021.651639] [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: 01/10/2021] [Accepted: 04/06/2021] [Indexed: 01/16/2023] Open
Abstract
Leber hereditary optic neuropathy (LHON) is a maternally inherited mitochondrial disease that specifically targets the retinal ganglion cells by reducing their ability to produce enough energy to sustain. The mutations of the mitochondrial DNA that cause LHON are silent until an unknown trigger causes bilateral central visual scotoma. After the onset of loss of vision, most patients experience progressive worsening within the following months. Few of them regain some vision after a period of ~1 year. Management of LHON patients has been focused on understanding the triggers of the disease and its pathophysiology to prevent the onset of visual loss in a carrier. Medical treatment is recommended once visual loss has started in at least one eye. Research evaluated drugs that are thought to be able to restore the mitochondrial electron transport chain of the retinal ganglion cells. Significant advances were made in evaluating free radical cell scavengers and gene therapy as potential treatments for LHON. Although encouraging the results of clinical trial have been mixed in stopping the worsening of visual loss. In patients with chronic disease of over 1 year, efficient treatment that restores vision is yet to be discovered. In this review, we summarize the management strategies for patients with LHON before, during, and after the loss of vision, explain the rationale and effectiveness of previous and current treatments, and report findings about emerging treatments.
Collapse
Affiliation(s)
- Rabih Hage
- Neuro-ophthalmology Department, Hôpital Fondation Rothschild, Paris, France
| | | |
Collapse
|
25
|
Newman NJ, Yu-Wai-Man P, Carelli V, Moster ML, Biousse V, Vignal-Clermont C, Sergott RC, Klopstock T, Sadun AA, Barboni P, DeBusk AA, Girmens JF, Rudolph G, Karanjia R, Taiel M, Blouin L, Smits G, Katz B, Sahel JA. Efficacy and Safety of Intravitreal Gene Therapy for Leber Hereditary Optic Neuropathy Treated within 6 Months of Disease Onset. Ophthalmology 2021; 128:649-660. [PMID: 33451738 DOI: 10.1016/j.ophtha.2020.12.012] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 12/10/2020] [Accepted: 12/10/2020] [Indexed: 12/22/2022] Open
Abstract
PURPOSE To evaluate the efficacy of a single intravitreal injection of rAAV2/2-ND4 in subjects with visual loss from Leber hereditary optic neuropathy (LHON). DESIGN RESCUE is a multicenter, randomized, double-masked, sham-controlled, phase 3 clinical trial. PARTICIPANTS Subjects with the m.11778G>A mitochondrial DNA mutation and vision loss ≤6 months from onset in 1 or both eyes were included. METHODS Each subject's right eye was randomly assigned (1:1) to treatment with rAAV2/2-ND4 (single injection of 9 × 1010 viral genomes in 90 μl) or to sham injection. The left eye received the treatment not allocated to the right eye. MAIN OUTCOME MEASURES The primary end point was the difference of the change from baseline in best-corrected visual acuity (BCVA) between rAAV2/2-ND4-treated and sham-treated eyes at week 48. Other outcome measures included contrast sensitivity, Humphrey visual field perimetry, retinal anatomic measures, and quality of life. Follow-up extended to week 96. RESULTS Efficacy analysis included 38 subjects. Mean age was 36.8 years, and 82% were male. Mean duration of vision loss at time of treatment was 3.6 months and 3.9 months in the rAAV2/2-ND4-treated eyes and sham-treated eyes, respectively. Mean baseline logarithm of the minimum angle of resolution (logMAR) BCVA (standard deviation) was 1.31 (0.52) in rAAV2/2-ND4-treated eyes and 1.26 (0.62) in sham-treated eyes, with a range from -0.20 to 2.51. At week 48, the difference of the change in BCVA from baseline between rAAV2/2-ND4-treated and sham-treated eyes was -0.01 logMAR (P = 0.89); the primary end point of a -0.3 logMAR (15-letter) difference was not met. The mean BCVA for both groups deteriorated over the initial weeks, reaching the worst levels at week 24, followed by a plateau phase until week 48, and then an improvement of +10 and +9 Early Treatment Diabetic Retinopathy Study letters equivalent from the plateau level in the rAAV2/2-ND4-treated and sham-treated eyes, respectively. CONCLUSIONS At 96 weeks after unilateral injection of rAAV2/2-ND4, LHON subjects carrying the m.11778G>A mutation treated within 6 months after vision loss achieved comparable visual outcomes in the injected and uninjected eyes.
Collapse
Affiliation(s)
- Nancy J Newman
- Departments of Ophthalmology, Neurology, and Neurological Surgery, Emory University School of Medicine, Atlanta, Georgia.
| | - Patrick Yu-Wai-Man
- Cambridge Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom; Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, United Kingdom; Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Valerio Carelli
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOC Clinica Neurologica, Bologna, Italy; Unit of Neurology, Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Mark L Moster
- Departments of Neurology and Ophthalmology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Valerie Biousse
- Departments of Ophthalmology, Neurology, and Neurological Surgery, Emory University School of Medicine, Atlanta, Georgia
| | - Catherine Vignal-Clermont
- Department of Neuro-Ophthalmology and Emergencies, Rothschild Foundation Hospital, Paris, France; Centre Hospitalier National d'Ophtalmologie des Quinze Vingts, Paris, France
| | - Robert C Sergott
- Departments of Neurology and Ophthalmology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Thomas Klopstock
- Department of Neurology, Friedrich-Baur-Institute, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany; German Center for Neurodegenerative Diseases, Munich, Germany; Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Alfredo A Sadun
- Doheny Eye Institute/UCLA School of Medicine, Los Angeles, California
| | - Piero Barboni
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOC Clinica Neurologica, Bologna, Italy
| | - Adam A DeBusk
- Departments of Neurology and Ophthalmology, Wills Eye Hospital and Thomas Jefferson University, Philadelphia, Pennsylvania
| | | | - Günther Rudolph
- Department of Ophthalmology, University Hospital, LMU Munich, Munich, Germany
| | - Rustum Karanjia
- Doheny Eye Institute/UCLA School of Medicine, Los Angeles, California; Department of Ophthalmology, University of Ottawa Eye, Ottawa, Ontario, Canada
| | | | | | | | | | - José-Alain Sahel
- Centre Hospitalier National d'Ophtalmologie des Quinze Vingts, Paris, France; Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France; Fondation Ophtalmologique A. de Rothschild, Paris, France; Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania; CHNO des Quinze-Vingts, Institut Hospitalo-Universitaire FOReSIGHT, INSERM-DGOS CIC, Paris, France
| | | |
Collapse
|
26
|
Amore G, Romagnoli M, Carbonelli M, Barboni P, Carelli V, La Morgia C. Therapeutic Options in Hereditary Optic Neuropathies. Drugs 2021; 81:57-86. [PMID: 33159657 PMCID: PMC7843467 DOI: 10.1007/s40265-020-01428-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Options for the effective treatment of hereditary optic neuropathies have been a long time coming. The successful launch of the antioxidant idebenone for Leber's Hereditary Optic Neuropathy (LHON), followed by its introduction into clinical practice across Europe, was an important step forward. Nevertheless, other options, especially for a variety of mitochondrial optic neuropathies such as dominant optic atrophy (DOA), are needed, and a number of pharmaceutical agents, acting on different molecular pathways, are currently under development. These include gene therapy, which has reached Phase III development for LHON, but is expected to be developed also for DOA, whilst most of the other agents (other antioxidants, anti-apoptotic drugs, activators of mitobiogenesis, etc.) are almost all at Phase II or at preclinical stage of research. Here, we review proposed target mechanisms, preclinical evidence, available clinical trials with primary endpoints and results, of a wide range of tested molecules, to give an overview of the field, also providing the landscape of future scenarios, including gene therapy, gene editing, and reproductive options to prevent transmission of mitochondrial DNA mutations.
Collapse
Affiliation(s)
- Giulia Amore
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Martina Romagnoli
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOC Clinica Neurologica, Bologna, Via Altura 3, 40139, Bologna, Italy
| | - Michele Carbonelli
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOC Clinica Neurologica, Bologna, Via Altura 3, 40139, Bologna, Italy
| | | | - Valerio Carelli
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOC Clinica Neurologica, Bologna, Via Altura 3, 40139, Bologna, Italy
| | - Chiara La Morgia
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOC Clinica Neurologica, Bologna, Via Altura 3, 40139, Bologna, Italy.
| |
Collapse
|
27
|
Yu H, Sant DW, Wang G, Guy J. Mitochondrial Transfer of the Mutant Human ND6T14484C Gene Causes Visual Loss and Optic Neuropathy. Transl Vis Sci Technol 2020; 9:1. [PMID: 33101779 PMCID: PMC7545076 DOI: 10.1167/tvst.9.11.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 09/01/2020] [Indexed: 01/08/2023] Open
Abstract
Purpose To evaluate the long-term effects of mitochondrial gene transfer of mutant human NADH ubiquinone oxidoreductase subunit VI (hND6T14484C) in the mouse eye. Methods Adult mice were injected intravitreally with mitochondrial-targeted adeno-associated virus carrying either hND6T14484C or mitochondrial encoded mCherry. The delivery and expression of the interest gene were detected by polymerase chain reaction (PCR), quantitative PCR (qPCR), and immunostaining. The pathologic effects of the mutant gene in live mice were assessed with RNA-seq, serial spectral domain optical coherence tomography (SD-OCT), and pattern electroretinogram (PERG). Results Delivered hND6 was found 30-fold greater than endogenous mouse ND6 in microdissected retinal ganglion cells of hND6-injected mice. Compared to controls injected with mCherry, PERG amplitude of hND6 mice dropped significantly at 3 (P = 0.0023), 6 (P = 0.0058), and 15 (P = 0.031) months after injection. SD-OCT revealed swelling of the optic nerve head followed by the progressive retinal and optic nerve atrophy in hND6 mice. Furthermore, RNA-seq data showed a change in 381 transcripts’ expression in these mice compared to mCherry mice. Postmortem analysis showed hND6 mice had marked atrophy of the entire optic nerve, from the globe to the optic chiasm, and a significant loss of retinal ganglion cells compared to age-matched control mice (P = 1.7E-9). Conclusions Delivered hND6T14484C induces visual loss and optic neuropathy in mice, the hallmarks of human Leber's hereditary optic neuropathy (LHON). Translational Relevance Results from this study will help establish a novel strategy not only to generate an LHON animal model but also to provide a potential to treat this or any other mitochondrial diseases.
Collapse
Affiliation(s)
- Hong Yu
- Bascom Palmer Eye Institute, University of Miami, Miller School of Medicine, Miami, FL, United States
| | - David W Sant
- Department of Biomedical Informatics, University of Utah, Salt Lake City, UT, United States
| | - Gaofeng Wang
- John P. Hussman Institute for Human Genomics, Dr. John T. MacDonald Foundation Department of Human Genetics, University of Miami, Miller School of Medicine, Miami, FL, United States
| | - John Guy
- Bascom Palmer Eye Institute, University of Miami, Miller School of Medicine, Miami, FL, United States
| |
Collapse
|
28
|
Wassmer SJ, De Repentigny Y, Sheppard D, Lagali PS, Fang L, Coupland SG, Kothary R, Guy J, Hauswirth WW, Tsilfidis C. XIAP Protects Retinal Ganglion Cells in the Mutant ND4 Mouse Model of Leber Hereditary Optic Neuropathy. Invest Ophthalmol Vis Sci 2020; 61:49. [PMID: 32735323 PMCID: PMC7425697 DOI: 10.1167/iovs.61.8.49] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Purpose Leber hereditary optic neuropathy (LHON) is a genetic form of vision loss that occurs primarily owing to mutations in the nicotinamide adenine dinucleotide dehydrogenase (ND) subunits that make up complex I of the electron transport chain. LHON mutations result in the apoptotic death of retinal ganglion cells. We tested the hypothesis that gene therapy with the X-linked inhibitor of apoptosis (XIAP) would prevent retinal ganglion cell apoptosis and reduce disease progression in a vector-induced mouse model of LHON that carries the ND4 mutation. Methods Adeno-associated virus (AAV) encoding full length hemagglutinin-tagged XIAP (AAV2.HA-XIAP) or green fluorescent protein (AAV2.GFP) was injected into the vitreous of DBA/1J mice. Two weeks later, the LHON phenotype was induced by AAV delivery of mutant ND4 (AAV2.mND4FLAG) to the vitreous. Retinal function was assessed by pattern electroretinography. Optic nerves were harvested at 4 months, and the effects of XIAP therapy on nerve fiber layer and optic nerve integrity were evaluated using immunohistochemistry, transmission electron microscopy and magnetic resonance imaging. Results During LHON disease progression, retinal ganglion cell axons are lost. Apoptotic cell bodies are seen in the nuclei of astrocytes or oligodendrocytes in the optic nerve, and there is thinning of the optic nerve and the nerve fiber layer of the retina. At 4 months after disease onset, XIAP gene therapy protects the nerve fiber layer and optic nerve architecture by preserving axon health. XIAP also decreases nuclear fragmentation in resident astrocytes or oligodendrocytes and decreases glial cell infiltration. Conclusions XIAP therapy improves optic nerve health and delays disease progression in LHON.
Collapse
|
29
|
Buck TM, Wijnholds J. Recombinant Adeno-Associated Viral Vectors (rAAV)-Vector Elements in Ocular Gene Therapy Clinical Trials and Transgene Expression and Bioactivity Assays. Int J Mol Sci 2020; 21:E4197. [PMID: 32545533 PMCID: PMC7352801 DOI: 10.3390/ijms21124197] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/09/2020] [Accepted: 06/10/2020] [Indexed: 02/06/2023] Open
Abstract
Inherited retinal dystrophies and optic neuropathies cause chronic disabling loss of visual function. The development of recombinant adeno-associated viral vectors (rAAV) gene therapies in all disease fields have been promising, but the translation to the clinic has been slow. The safety and efficacy profiles of rAAV are linked to the dose of applied vectors. DNA changes in the rAAV gene cassette affect potency, the expression pattern (cell-specificity), and the production yield. Here, we present a library of rAAV vectors and elements that provide a workflow to design novel vectors. We first performed a meta-analysis on recombinant rAAV elements in clinical trials (2007-2020) for ocular gene therapies. We analyzed 33 unique rAAV gene cassettes used in 57 ocular clinical trials. The rAAV gene therapy vectors used six unique capsid variants, 16 different promoters, and six unique polyadenylation sequences. Further, we compiled a list of promoters, enhancers, and other sequences used in current rAAV gene cassettes in preclinical studies. Then, we give an update on pro-viral plasmid backbones used to produce the gene therapy vectors, inverted terminal repeats, production yield, and rAAV safety considerations. Finally, we assess rAAV transgene and bioactivity assays applied to cells or organoids in vitro, explants ex vivo, and clinical studies.
Collapse
Affiliation(s)
- Thilo M. Buck
- Department of Ophthalmology, Leiden University Medical Center (LUMC), 2333 ZC Leiden, The Netherlands;
| | - Jan Wijnholds
- Department of Ophthalmology, Leiden University Medical Center (LUMC), 2333 ZC Leiden, The Netherlands;
- Netherlands Institute of Neuroscience, Royal Netherlands Academy of Arts and Sciences (KNAW), 1105 BA Amsterdam, The Netherlands
| |
Collapse
|
30
|
Gene Therapy with Single-Subunit Yeast NADH-Ubiquinone Oxidoreductase (NDI1) Improves the Visual Function in Experimental Autoimmune Encephalomyelitis (EAE) Mice Model of Multiple Sclerosis (MS). Mol Neurobiol 2020; 57:1952-1965. [PMID: 31900864 DOI: 10.1007/s12035-019-01857-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 12/12/2019] [Indexed: 12/14/2022]
Abstract
Mitochondrial dysfunction mediated loss of respiration, oxidative stress, and loss of cellular homeostasis contributes to the neuronal and axonal degenerations permanent loss of function in experimental autoimmune encephalomyelitis model (EAE) of multiple sclerosis (MS). To address the mitochondrial dysfunction mediated visual loss in EAE mice, self-complementary adeno-associated virus (scAAV) containing the NADH-dehydrogenase type-2 (NDI1) complex I gene was intravitreally injected into the mice after the onset of visual defects. Visual function assessed by pattern electroretinogram (PERGs) showed progressive loss of function in EAE mice were improved significantly in NDI1 gene therapy-treated mice. Serial optical coherence tomography (OCT) revealed that progressive thinning of inner retinal layers in EAE mice was prevented upon NDI1 expression. The 45% optic nerve axonal and 33% retinal ganglion cell (RGC) loss contributed to the permanent loss of visual function in EAE mice were ameliorated by NDI1-mediated prevention of mitochondrial cristae dissolution and improved mitochondrial homeostasis. In conclusion, targeting the dysfunctional complex I using NDI1 gene can be an approach to address axonal and neuronal loss responsible for permanent disability in MS that is unaltered by current disease modifying drugs.
Collapse
|
31
|
Karaarslan C. Leber's Hereditary Optic Neuropathy as a Promising Disease for Gene Therapy Development. Adv Ther 2019; 36:3299-3307. [PMID: 31605306 PMCID: PMC6860503 DOI: 10.1007/s12325-019-01113-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Indexed: 12/13/2022]
Abstract
Leber's hereditary optic neuropathy (LHON) is a relatively common, rapidly progressing inherited optic neuropathy wherein LHON-affected eyes undergo optic nerve atrophy due to retinal ganglion cell (RGC) loss. It is a maternally inherited (or sporadic) mitochondrial disorder caused primarily by mutations in genes that encode components of respiratory complex (RC)1 in mitochondria. Mitochondrial deficiency of RC1 compromises ATP production and oxidative stress management in RGCs. The most common LHON-causing mutations are 11778G>A, 3460G>A, and 14484T>C point mutations in MT-ND4, MT-ND1, and MT-ND6. The unusually high mitochondrial load of RGCs makes them particularly sensitive to these mutations. Patients with LHON may be prescribed ubiquinone (a component of RC3) or idebenone, a ubiquinone analogue with enhanced bioavailability to act downstream of RC1. The challenge of accessing the inner mitochondrial membrane with gene therapy for LHON, and other mitochondrial diseases, may be overcome by incorporation of a specific mitochondrion-targeting sequence (MTS) that enables allotropic expression of a nucleus-transcribed ND4 transgene. Because LHON penetrance is incomplete among carriers of the aforementioned mutations, identification of environmental factors, such as heavy smoking, that interact with genetics in the phenotypic expression of LHON may be helpful toward preventing or delaying disease development. LHON has become a model for mitochondrial and neurogenerative diseases owing to it having a clearly identified genetic cause and its early onset and rapid progression characteristics. Hence, LHON studies and genetic treatment advances may inform research of other diseases.
Collapse
|
32
|
Weissig V. Drug Development for the Therapy of Mitochondrial Diseases. Trends Mol Med 2019; 26:40-57. [PMID: 31727544 DOI: 10.1016/j.molmed.2019.09.002] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 09/11/2019] [Accepted: 09/12/2019] [Indexed: 02/07/2023]
Abstract
Mitochondrial diseases are a heterogeneous group of inherited or acquired devastating disorders that affect the energy metabolism of the body. Many strategies have been investigated, but currently there is no FDA-approved drug that can alleviate disease symptoms or slow disease progression. This review analyzes to what extent growing knowledge over the past two decades about the etiology and pathogenesis of mitochondrial diseases is reflected in the design and development of new experimental drugs for the therapy of these disorders. All currently registered clinical trials involving new experimental drug entities are reviewed to evaluate how far away we are from the first FDA-approved drug therapy for mitochondrial disease.
Collapse
Affiliation(s)
- Volkmar Weissig
- Midwestern University College of Pharmacy at Glendale, Department of Pharmaceutical Sciences and Nanocenter of Excellence, Glendale, AZ, USA.
| |
Collapse
|
33
|
Kurimoto T, Ueda K, Mori S, Sakamoto M, Yamada-Nakanishi Y, Matsumiya W, Nakamura M. A study protocol for evaluating the efficacy and safety of skin electrical stimulation for Leber hereditary optic neuropathy: a single-arm, open-label, non-randomized prospective exploratory study. Clin Ophthalmol 2019; 13:897-904. [PMID: 31213761 PMCID: PMC6549395 DOI: 10.2147/opth.s204669] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Accepted: 04/12/2019] [Indexed: 12/02/2022] Open
Abstract
Background: Leber hereditary optic neuropathy (LHON) is a maternally inherited disease caused by three missense mutations of mitochondrial (mt) DNA, ie, m 3460 G>A, m 11778 G>A, or m 14484 T>C in the greater portion of LHON. m 11778 G>A mutation is especially observed in >90% of the cases in Japanese families. Although spontaneous remission of visual function infrequently occurs, effective treatment for LHON remains unestablished. Transcorneal electrical stimulation has been shown to be efficacious in individuals with optic neuropathy. However, due to potential risk of corneal damage, repeated treatments are not permissible. In this exploratory study, we will be conducting skin electrical stimulation (SES) as an intervention for patients with LHON having 11778 missense mutation and investigate effectiveness and safety of SES. Methods: This is a single-arm, prospective, open-label exploratory trial focused on patients with LHON having 11778 missense mutation. Eleven patients will be enrolled and receive six consecutive SES once every 2 weeks up to 10 weeks. The safety of the SES will be monitored with specular microscopy, slit-lamp biomicroscopy, fundus examinations, and the observation of facial skin. The primary outcome measure will be the averaged l ogarithm of minimum angle resolution (logMAR) converted visual acuity 1 week after the last SES. Secondary outcome measures include changes, in logMAR at 4 and 8 weeks after the last SES, such as visual field indices measured using Humphrey visual field and microperimetry-3, the thickness of peripapillary retinal fiber and macular ganglion cell complex, multifocal visual evoked potentials, critical flicker frequency, and color vision. Discussion: The results of this proposed proof-of-concept feasibility trial will help plan and execute a larger definitive trial to test SES as an effective strategy for LHON and related optic neuropathies and help establish a beneficial treatment for LHON.
Collapse
Affiliation(s)
- Takuji Kurimoto
- Division of Ophthalmology, Department of Surgery, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Kaori Ueda
- Division of Ophthalmology, Department of Surgery, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Sotaro Mori
- Division of Ophthalmology, Department of Surgery, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Mari Sakamoto
- Division of Ophthalmology, Department of Surgery, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Yuko Yamada-Nakanishi
- Division of Ophthalmology, Department of Surgery, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Wataru Matsumiya
- Division of Ophthalmology, Department of Surgery, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Makoto Nakamura
- Division of Ophthalmology, Department of Surgery, Kobe University Graduate School of Medicine, Kobe, Japan
| |
Collapse
|
34
|
|
35
|
Bioactivity and gene expression profiles of hiPSC-generated retinal ganglion cells in MT-ND4 mutated Leber's hereditary optic neuropathy. Exp Cell Res 2018; 363:299-309. [PMID: 29366807 DOI: 10.1016/j.yexcr.2018.01.020] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 01/09/2018] [Accepted: 01/15/2018] [Indexed: 01/01/2023]
Abstract
Leber's hereditary optic neuropathy (LHON) is the maternally inherited mitochondrial disease caused by homoplasmic mutations in mitochondrial electron transport chain Complex I subunit genes. The mechanism of its incomplete penetrance is still largely unclear. In this study, we created the patient-specific human induced pluripotent stem cells (hiPSCs) from MT-ND4 mutated LHON-affected patient, asymptomatic mutation carrier and healthy control, and differentiated them into retinal ganglion cells (RGCs). We found the defective neurite outgrowth in affected RGCs, but not in the carrier RGCs which had significant expression of SNCG gene. We observed enhanced mitochondrial biogenesis in affected and carrier derived RGCs. Surprisingly, we observed increased NADH dehydrogenase enzymatic activity of Complex I in hiPSC-derived RGCs of asymptomatic carrier, but not of the affected patient. LHON mutation substantially decreased basal respiration in both affected and unaffected carrier hiPSCs, and had the same effect on spare respiratory capacity, which ensures normal function of mitochondria in conditions of increased energy demand or environmental stress. The expression of antioxidant enzyme catalase was decreased in affected and carrier patient hiPSC-derived RGCs as compared to the healthy control, which might indicate to higher oxidative stress-enriched environment in the LHON-specific RGCs. Microarray profiling demonstrated enhanced expression of cell cycle machinery and downregulation of neuronal specific genes.
Collapse
|
36
|
Vignal C, Uretsky S, Fitoussi S, Galy A, Blouin L, Girmens JF, Bidot S, Thomasson N, Bouquet C, Valero S, Meunier S, Combal JP, Gilly B, Katz B, Sahel JA. Safety of rAAV2/2- ND4 Gene Therapy for Leber Hereditary Optic Neuropathy. Ophthalmology 2018; 125:945-947. [DOI: 10.1016/j.ophtha.2017.12.036] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 12/27/2017] [Accepted: 12/28/2017] [Indexed: 12/16/2022] Open
|
37
|
Guy J, Feuer WJ, Davis JL, Porciatti V, Gonzalez PJ, Koilkonda RD, Yuan H, Hauswirth WW, Lam BL. Gene Therapy for Leber Hereditary Optic Neuropathy: Low- and Medium-Dose Visual Results. Ophthalmology 2017. [PMID: 28647203 DOI: 10.1016/j.ophtha.2017.05.016] [Citation(s) in RCA: 143] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
PURPOSE To determine the effects of AAV2(Y444,500,730F)-P1ND4v2 in patients with Leber hereditary optic neuropathy (LHON). DESIGN Prospective open-label, unilateral single-dose, intravitreal injection of AAV2(Y444,500,730F)-P1ND4v2 per participant. PARTICIPANTS Fourteen patients with visual loss and mutated G11778A mitochondrial DNA. METHODS Intravitreal injection with the gene therapy vector AAV2(Y444,500,730F)-P1ND4v2 into 1 eye. Six participants with chronic bilateral visual loss lasting more than 12 months (group 1), 6 participants with bilateral visual loss lasting less than 12 months (group 2), and 2 participants with unilateral visual loss (group 3) were treated. Nine patients had at least 12 months of follow-up. Clinical testing included visual acuity, visual fields, optical coherence tomography, pattern electroretinography, and neuro-ophthalmic examinations. Generalized estimating equation methods were used for longitudinal analyses. MAIN OUTCOME MEASURE Loss of visual acuity. RESULTS For groups 1 and 2, month 12 average acuity improvements with treatment relative to baseline were 0.24 logarithm of the minimum angle of resolution (logMAR). Fellow eyes had a 0.09-logMAR improvement. A post hoc comparison found that at month 12, the difference between study eye minus fellow eye improvement in group 2 patients of 0.53 logMAR was greater than that observed in our prior acute natural history patients of 0.21 logMAR (P = 0.053). At month 18, the difference between study eye minus fellow eye improvement in our acute group 2 gene therapy patients of 0.96 was more than that observed in our prior acute natural history patients (0.17 logMAR; P < 0.001). Two patients demonstrated asymptomatic uveitis that resolved without treatment. Optical coherence tomography of treated eyes showed an average temporal retinal nerve fiber layer thickness of 54 μm before injection and 55 μm at month 12. For fellow eyes before injection, it was 56 μm, decreasing to 50 μm at month 12 (P = 0.013). Generalized estimating equations suggested that PERG amplitudes worsened more in treated eyes than in fellow eyes by approximately 0.05 μV (P = 0.009 exchangeable). No difference between eyes in outcomes of other visual function measures was evident. CONCLUSIONS Allotopic gene therapy for LHON at low and medium doses seems to be safe and does not damage the temporal retinal nerve fiber layer, opening the door next for testing of the high dose.
Collapse
Affiliation(s)
- John Guy
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida.
| | - William J Feuer
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Janet L Davis
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Vittorio Porciatti
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Phillip J Gonzalez
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Rajeshwari D Koilkonda
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Huijun Yuan
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - William W Hauswirth
- Department of Ophthalmology University of Florida College of Medicine, Gainesville, Florida
| | - Byron L Lam
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| |
Collapse
|
38
|
Correction of Monogenic and Common Retinal Disorders with Gene Therapy. Genes (Basel) 2017; 8:genes8020053. [PMID: 28134823 PMCID: PMC5333042 DOI: 10.3390/genes8020053] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 01/19/2017] [Indexed: 11/16/2022] Open
Abstract
The past decade has seen major advances in gene-based therapies, many of which show promise for translation to human disease. At the forefront of research in this field is ocular disease, as the eye lends itself to gene-based interventions due to its accessibility, relatively immune-privileged status, and ability to be non-invasively monitored. A landmark study in 2001 demonstrating successful gene therapy in a large-animal model for Leber congenital amaurosis set the stage for translation of these strategies from the bench to the bedside. Multiple clinical trials have since initiated for various retinal diseases, and further improvements in gene therapy techniques have engendered optimism for alleviating inherited blinding disorders. This article provides an overview of gene-based strategies for retinal disease, current clinical trials that engage these strategies, and the latest techniques in genome engineering, which could serve as the next frontline of therapeutic interventions.
Collapse
|
39
|
Abstract
As our understanding of the genetic basis for inherited retinal disease has expanded, gene therapy has advanced into clinical development. When the gene mutations associated with inherited retinal dystrophies were identified, it became possible to create animal models in which individual gene were altered to match the human mutations. The retina of these animals were then characterized to assess whether the mutated genes produced retinal phenotypes characteristic of disease-affected patients. Following the identification of a subpopulation of patients with the affected gene and the development of techniques for the viral gene transduction of retinal cells, it has become possible to deliver a copy of the normal gene into the retinal sites of the mutated genes. When this was performed in animal models of monogenic diseases, at an early stage of retinal degeneration when the affected cells remained viable, successful gene augmentation corrected the structural and functional lesions characteristic of the specific diseases in the areas of the retina that were successfully transduced. These studies provided the essential proof-of-concept needed to advance monogenic gene therapies into clinic development; these therapies include treatments for: Leber's congenital amaurosis type 2, caused by mutations to RPE65, retinoid isomerohydrolase; choroideremia, caused by mutations to REP1, Rab escort protein 1; autosomal recessive Stargardt disease, caused by mutations to ABCA4, the photoreceptor-specific ATP-binding transporter; Usher 1B disease caused by mutations to MYO7A, myosin heavy chain 7; X-linked juvenile retinoschisis caused by mutations to RS1, retinoschisin; autosomal recessive retinitis pigmentosa caused by mutations to MERTK, the proto-oncogene tyrosine-protein kinase MER; Leber's hereditary optic neuropathy caused by mutations to ND4, mitochondrial nicotinamide adenine dinucleotide ubiquinone oxidoreductase (complex I) subunit 4 and achromatopsia, caused by mutations to CNGA3, cyclic nucleotide-gated channel alpha 3 and CNGB3, cyclic nucleotide-gated channel beta 3. This review includes a tabulated summary of treatments for these monogenic retinal dystrophies that have entered into clinical development, as well as a brief summary of the preclinical data that supported their advancement into clinical development.
Collapse
|
40
|
Boominathan A, Vanhoozer S, Basisty N, Powers K, Crampton AL, Wang X, Friedricks N, Schilling B, Brand MD, O'Connor MS. Stable nuclear expression of ATP8 and ATP6 genes rescues a mtDNA Complex V null mutant. Nucleic Acids Res 2016; 44:9342-9357. [PMID: 27596602 PMCID: PMC5100594 DOI: 10.1093/nar/gkw756] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 08/15/2016] [Accepted: 08/17/2016] [Indexed: 12/29/2022] Open
Abstract
We explore the possibility of re-engineering mitochondrial genes and expressing them from the nucleus as an approach to rescue defects arising from mitochondrial DNA mutations. We have used a patient cybrid cell line with a single point mutation in the overlap region of the ATP8 and ATP6 genes of the human mitochondrial genome. These cells are null for the ATP8 protein, have significantly lowered ATP6 protein levels and no Complex V function. Nuclear expression of only the ATP8 gene with the ATP5G1 mitochondrial targeting sequence appended restored viability on Krebs cycle substrates and ATP synthesis capabilities but, failed to restore ATP hydrolysis and was insensitive to various inhibitors of oxidative phosphorylation. Co-expressing both ATP8 and ATP6 genes under similar conditions resulted in stable protein expression leading to successful integration into Complex V of the oxidative phosphorylation machinery. Tests for ATP hydrolysis / synthesis, oxygen consumption, glycolytic metabolism and viability all indicate a significant functional rescue of the mutant phenotype (including re-assembly of Complex V) following stable co-expression of ATP8 and ATP6 Thus, we report the stable allotopic expression, import and function of two mitochondria encoded genes, ATP8 and ATP6, resulting in simultaneous rescue of the loss of both mitochondrial proteins.
Collapse
Affiliation(s)
| | - Shon Vanhoozer
- SENS Research Foundation Research Center, Mountain View, CA 94041, USA
| | - Nathan Basisty
- Keck School of Medicine of USC, Los Angeles, CA 90033, USA
| | - Kathleen Powers
- SENS Research Foundation Research Center, Mountain View, CA 94041, USA
| | | | - Xiaobin Wang
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Natalie Friedricks
- Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | | | - Martin D Brand
- Keck School of Medicine of USC, Los Angeles, CA 90033, USA
| | | |
Collapse
|
41
|
Abstract
Leber hereditary optic neuropathy (LHON) was the first clinically characterized mitochondrial disorder. Since its first description in 1871, much has been discovered regarding the genetics and pathophysiology of the disease. This has enabled the development of in vitro cell and animal models that can be used to try to determine not only the effects of the genetic mutation upon the clinical phenotype but to also test potential novel therapies. Treatments for LHON have ranged from vitamins and minerals to immunosuppressants and, more recently, targeted gene therapy. This article reviews the pathophysiology and clinical features of LHON with a focus on translational research.
Collapse
Affiliation(s)
- Nailyn Rasool
- a Neuro-Ophthalmology Service, Massachusetts Eye and Ear Infirmary, Harvard Medical School , Boston , Massachusetts , USA
| | - Simmons Lessell
- a Neuro-Ophthalmology Service, Massachusetts Eye and Ear Infirmary, Harvard Medical School , Boston , Massachusetts , USA
| | - Dean M Cestari
- a Neuro-Ophthalmology Service, Massachusetts Eye and Ear Infirmary, Harvard Medical School , Boston , Massachusetts , USA
| |
Collapse
|
42
|
Gueven N, Nadikudi M, Daniel A, Chhetri J. Targeting mitochondrial function to treat optic neuropathy. Mitochondrion 2016; 36:7-14. [PMID: 27476756 DOI: 10.1016/j.mito.2016.07.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 01/03/2023]
Abstract
Many reports have illustrated a tight connection between vision and mitochondrial function. Not only are most mitochondrial diseases associated with some form of vision impairment, many ophthalmological disorders such as glaucoma, age-related macular degeneration and diabetic retinopathy also show signs of mitochondrial dysfunction. Despite a vast amount of evidence, vision loss is still only treated symptomatically, which is only partially a consequence of resistance to acknowledge that mitochondria could be the common denominator and hence a promising therapeutic target. More importantly, clinical support of this concept is only emerging. Moreover, only a few drug candidates and treatment strategies are in development or approved that selectively aim to restore mitochondrial function. This review rationalizes the currently developed therapeutic approaches that target mitochondrial function by discussing their proposed mode(s) of action and provides an overview on their development status with regards to optic neuropathies.
Collapse
Affiliation(s)
- Nuri Gueven
- Pharmacy, School of Medicine, University of Tasmania, Hobart, TAS, Australia.
| | - Monila Nadikudi
- Pharmacy, School of Medicine, University of Tasmania, Hobart, TAS, Australia
| | - Abraham Daniel
- Pharmacy, School of Medicine, University of Tasmania, Hobart, TAS, Australia
| | - Jamuna Chhetri
- Pharmacy, School of Medicine, University of Tasmania, Hobart, TAS, Australia
| |
Collapse
|
43
|
Marangoni D, Bush RA, Zeng Y, Wei LL, Ziccardi L, Vijayasarathy C, Bartoe JT, Palyada K, Santos M, Hiriyanna S, Wu Z, Colosi P, Sieving PA. Ocular and systemic safety of a recombinant AAV8 vector for X-linked retinoschisis gene therapy: GLP studies in rabbits and Rs1-KO mice. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2016; 5:16011. [PMID: 27626041 PMCID: PMC5008245 DOI: 10.1038/mtm.2016.11] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Revised: 01/15/2016] [Accepted: 01/18/2016] [Indexed: 01/10/2023]
Abstract
X-linked retinoschisis (XLRS) is a retinal disease caused by mutations in the gene encoding the protein retinoschisin (RS1) and is one of the most common causes of macular degeneration in young men. Our therapeutic approach for XLRS is based on the administration of AAV8-scRS/IRBPhRS, an adeno-associated viral vector coding the human RS1 protein, via the intravitreal (IVT) route. Two Good Laboratory Practice studies, a 9-month study in New Zealand White rabbits (n = 124) injected with AAV8-scRS/IRBPhRS at doses of 2E9, 2E10, 2E11, and 1.5E12 vector genomes/eye (vg/eye), and a 6-month study in Rs1-KO mice (n = 162) dosed with 2E9 and 2E10 vg/eye of the same vector were conducted to assess ocular and systemic safety. A self-resolving, dose-dependent vitreal inflammation was the main ocular finding, and except for a single rabbit dosed with 1.5E12 vg/eye, which showed a retinal detachment, no other ocular adverse event was reported. Systemic toxicity was not identified in either species. Biodistribution analysis in Rs1-KO mice detected spread of vector genome in extraocular tissues, but no evidence of organ or tissues damage was found. These studies indicate that IVT administration of AAV8-scRS/IRBPhRS is safe and well tolerated and support its advancement into a phase 1/2a clinical trial for XLRS.
Collapse
Affiliation(s)
- Dario Marangoni
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland, USA; Department of Biotechnology and Applied Clinical Science, University of L'Aquila, L'Aquila, Italy
| | - Ronald A Bush
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health , Bethesda, Maryland, USA
| | - Yong Zeng
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health , Bethesda, Maryland, USA
| | - Lisa L Wei
- National Eye Institute, National Institutes of Health , Bethesda, Maryland, USA
| | - Lucia Ziccardi
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health , Bethesda, Maryland, USA
| | - Camasamudram Vijayasarathy
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health , Bethesda, Maryland, USA
| | | | | | - Maria Santos
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health , Bethesda, Maryland, USA
| | - Suja Hiriyanna
- National Eye Institute, National Institutes of Health , Bethesda, Maryland, USA
| | - Zhijian Wu
- National Eye Institute, National Institutes of Health , Bethesda, Maryland, USA
| | - Peter Colosi
- National Eye Institute, National Institutes of Health , Bethesda, Maryland, USA
| | - Paul A Sieving
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland, USA; National Eye Institute, National Institutes of Health, Bethesda, Maryland, USA
| |
Collapse
|
44
|
Abstract
PURPOSE OF REVIEW To discuss recent advances in potential treatments for Leber hereditary optic neuropathy (LHON), a typically visually devastating hereditary optic neuropathy caused by mutations in the mitochondrial genome. RECENT FINDINGS Idebenone has been proposed as a means of bypassing defective complex I activity and a free radical scavenger to prevent oxidative damage. EPI-743 may have more potency than idebenone, but no clinical trials have been performed. Gene therapy techniques have advanced significantly, including allotopic expression and nuclear transfer. Successful rescue of animal models of LHON with both of these therapies has been demonstrated. Introduction of exogenous DNA into the mitochondrial genome with mitochondrial targeting of viral vectors is another promising technique. SUMMARY There are currently no proven treatments for LHON. However, there are many promising novel treatment modalities that are currently being evaluated, with several clinical trials underway or in the planning stages. Supportive measures and genetic counseling remain of great importance for these patients.
Collapse
|
45
|
Wan X, Pei H, Zhao MJ, Yang S, Hu WK, He H, Ma SQ, Zhang G, Dong XY, Chen C, Wang DW, Li B. Efficacy and Safety of rAAV2-ND4 Treatment for Leber's Hereditary Optic Neuropathy. Sci Rep 2016; 6:21587. [PMID: 26892229 PMCID: PMC4759604 DOI: 10.1038/srep21587] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 01/26/2016] [Indexed: 11/09/2022] Open
Abstract
Leber's hereditary optic neuropathy (LHON) is a mitochondrially inherited disease leading to blindness. A mitochondrial DNA point mutation at the 11778 nucleotide site of the NADH dehydrogenase subunit 4 (ND4) gene is the most common cause. The aim of this study was to evaluate the efficacy and safety of a recombinant adeno-associated virus 2 (AAV2) carrying ND4 (rAAV2-ND4) in LHON patients carrying the G11778A mutation. Nine patients were administered rAAV2-ND4 by intravitreal injection to one eye and then followed for 9 months. Ophthalmologic examinations of visual acuity, visual field, and optical coherence tomography were performed. Physical examinations included routine blood and urine. The visual acuity of the injected eyes of six patients improved by at least 0.3 log MAR after 9 months of follow-up. In these six patients, the visual field was enlarged but the retinal nerve fibre layer remained relatively stable. No other outcome measure was significantly changed. None of the nine patients had local or systemic adverse events related to the vector during the 9-month follow-up period. These findings support the feasible use of gene therapy for LHON.
Collapse
Affiliation(s)
- Xing Wan
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Han Pei
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Min-jian Zhao
- Department of Oncology, Central Hospital, Ezhou City, China
| | - Shuo Yang
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Wei-kun Hu
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Heng He
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Si-qi Ma
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ge Zhang
- Department of Microbial and Biochemical Pharmacy, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Xiao-yan Dong
- Beijing FivePlus Molecular Medicine Institute Co. Ltd., Beijing, China
| | - Chen Chen
- Center Genetic Diagnosis, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Dao-wen Wang
- Center Genetic Diagnosis, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Bin Li
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| |
Collapse
|
46
|
Bénit P, Schiff M, Cwerman-Thibault H, Corral-Debrinski M, Rustin P. Drug development for mitochondrial disease: recent progress, current challenges, and future prospects. Expert Opin Orphan Drugs 2015. [DOI: 10.1517/21678707.2016.1117972] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
47
|
Feuer WJ, Schiffman JC, Davis JL, Porciatti V, Gonzalez P, Koilkonda RD, Yuan H, Lalwani A, Lam BL, Guy J. Gene Therapy for Leber Hereditary Optic Neuropathy: Initial Results. Ophthalmology 2015; 123:558-70. [PMID: 26606867 DOI: 10.1016/j.ophtha.2015.10.025] [Citation(s) in RCA: 175] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 10/13/2015] [Accepted: 10/13/2015] [Indexed: 01/01/2023] Open
Abstract
PURPOSE Leber hereditary optic neuropathy (LHON) is a disorder characterized by severe and rapidly progressive visual loss when caused by a mutation in the mitochondrial gene encoding NADH:ubiquinone oxidoreductase subunit 4 (ND4). We have initiated a gene therapy trial to determine the safety and tolerability of escalated doses of an adeno-associated virus vector (AAV) expressing a normal ND4 complementary DNA in patients with a G to A mutation at nucleotide 11778 of the mitochondrial genome. DESIGN In this prospective open-label trial (NCT02161380), the study drug (self-complementary AAV [scAAV]2(Y444,500,730F)-P1ND4v2) was intravitreally injected unilaterally into the eyes of 5 blind participants with G11778A LHON. Four participants with visual loss for more than 12 months were treated. The fifth participant had visual loss for less than 12 months. The first 3 participants were treated at the low dose of vector (5 × 10(9) vg), and the fourth participant was treated at the medium dose (2.46 × 10(10) vg). The fifth participant with visual loss for less than 12 months received the low dose. Treated participants were followed for 90 to 180 days and underwent ocular and systemic safety assessments along with visual structure and function examinations. PARTICIPANTS Five legally blind patients with G11778A LHON. MAIN OUTCOME MEASURES Loss of visual acuity. RESULTS Visual acuity as measured by the Early Treatment Diabetic Retinopathy Study (ETDRS) eye chart remained unchanged from baseline to 3 months in the first 3 participants. For 2 participants with 90-day follow-up, acuity increased from hand movements to 7 letters in 1 and by 15 letters in 1, representing an improvement equivalent to 3 lines. No one lost vision, and no serious adverse events were observed. Minor adverse events included a transient increase of intraocular pressure (IOP), exposure keratitis, subconjunctival hemorrhage, a sore throat, and a transient increase in neutralizing antibodies (NAbs) against AAV2 in 1 participant. All blood samples were negative for vector DNA. CONCLUSIONS No serious safety problems were observed in the first 5 participants enrolled in this phase I trial of virus-based gene transfer in this mitochondrial disorder. Additional study follow-up of these and additional participants planned for the next 4 years is needed to confirm these preliminary observations.
Collapse
Affiliation(s)
- William J Feuer
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Joyce C Schiffman
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Janet L Davis
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Vittorio Porciatti
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Phillip Gonzalez
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Rajeshwari D Koilkonda
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Huijun Yuan
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Anil Lalwani
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Byron L Lam
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - John Guy
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida.
| |
Collapse
|
48
|
Abstract
Mitochondrial dysfunction underlies many human disorders, including those that affect the visual system. The retinal ganglion cells, whose axons form the optic nerve, are often damaged by mitochondrial-related diseases which result in blindness. Both mitochondrial DNA (mtDNA) and nuclear gene mutations impacting many different mitochondrial processes can result in optic nerve disease. Of particular importance are mutations that impair mitochondrial network dynamics (fusion and fission), oxidative phosphorylation (OXPHOS), and formation of iron-sulfur complexes. Current genetic knowledge can inform genetic counseling and suggest strategies for novel gene-based therapies. Identifying new optic neuropathy-causing genes and defining the role of current and novel genes in disease will be important steps toward the development of effective and potentially neuroprotective therapies.
Collapse
Affiliation(s)
- Janey L Wiggs
- Department of Ophthalmology, Harvard Medical School and Massachusetts Eye and Ear, Boston, Massachusetts 02114;
| |
Collapse
|
49
|
Nuclear expression of mitochondrial ND4 leads to the protein assembling in complex I and prevents optic atrophy and visual loss. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2015; 2:15003. [PMID: 26029714 PMCID: PMC4444999 DOI: 10.1038/mtm.2015.3] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 01/05/2015] [Accepted: 01/09/2015] [Indexed: 12/13/2022]
Abstract
Leber hereditary optic neuropathy is due to mitochondrial DNA mutations; in ~70% of all cases, a point mutation in the mitochondrial NADH dehydrogenase subunit 4, ND4, gene leads to central vision loss. We optimized allotopic expression (nuclear transcription of a gene that is normally transcribed inside the mitochondria) aimed at designing a gene therapy for ND4; its coding sequence was associated with the cis-acting elements of the human COX10 mRNA to allow the efficient mitochondrial delivery of the protein. After ocular administration to adult rats of a recombinant adeno-associated viral vector containing the human ND4 gene, we demonstrated that: (i) the sustained expression of human ND4 did not lead to harmful effects, instead the human protein is efficiently imported inside the mitochondria and assembled in respiratory chain complex I; (ii) the presence of the human protein in the experimental model of Leber hereditary optic neuropathy significantly prevents retinal ganglion cell degeneration and preserves both complex I function in optic nerves and visual function. Hence, the use of optimized allotopic expression is relevant for treating mitochondrial disorders due to mutations in the organelle genome.
Collapse
|