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Liu Y, Zong X, Cao W, Zhang W, Zhang N, Yang N. Gene Therapy for Retinitis Pigmentosa: Current Challenges and New Progress. Biomolecules 2024; 14:903. [PMID: 39199291 PMCID: PMC11352491 DOI: 10.3390/biom14080903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2024] [Revised: 07/14/2024] [Accepted: 07/23/2024] [Indexed: 09/01/2024] Open
Abstract
Retinitis pigmentosa (RP) poses a significant threat to eye health worldwide, with prevalence rates of 1 in 5000 worldwide. This genetically diverse retinopathy is characterized by the loss of photoreceptor cells and atrophy of the retinal pigment epithelium. Despite the involvement of more than 3000 mutations across approximately 90 genes in its onset, finding an effective treatment has been challenging for a considerable time. However, advancements in scientific research, especially in gene therapy, are significantly expanding treatment options for this most prevalent inherited eye disease, with the discovery of new compounds, gene-editing techniques, and gene loci offering hope for more effective treatments. Gene therapy, a promising technology, utilizes viral or non-viral vectors to correct genetic defects by either replacing or silencing disease-causing genes, potentially leading to complete recovery. In this review, we primarily focus on the latest applications of gene editing research in RP. We delve into the most prevalent genes associated with RP and discuss advancements in genome-editing strategies currently employed to correct various disease-causing mutations.
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Affiliation(s)
| | | | | | | | - Ningzhi Zhang
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Jiefang Road #238, Wuhan 430060, China; (Y.L.); (X.Z.); (W.C.); (W.Z.)
| | - Ning Yang
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Jiefang Road #238, Wuhan 430060, China; (Y.L.); (X.Z.); (W.C.); (W.Z.)
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Li S, Chen L, Fu Y. Nanotechnology-based ocular drug delivery systems: recent advances and future prospects. J Nanobiotechnology 2023; 21:232. [PMID: 37480102 PMCID: PMC10362606 DOI: 10.1186/s12951-023-01992-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 07/09/2023] [Indexed: 07/23/2023] Open
Abstract
Ocular drug delivery has constantly challenged ophthalmologists and drug delivery scientists due to various anatomical and physiological barriers. Static and dynamic ocular barriers prevent the entry of exogenous substances and impede therapeutic agents' active absorption. This review elaborates on the anatomy of the eye and the associated constraints. Followed by an illustration of some common ocular diseases, including glaucoma and their current clinical therapies, emphasizing the significance of drug therapy in treating ocular diseases. Subsequently, advances in ocular drug delivery modalities, especially nanotechnology-based ocular drug delivery systems, are recommended, and some typical research is highlighted. Based on the related research, systematic and comprehensive characterizations of the nanocarriers are summarized, hoping to assist with future research. Besides, we summarize the nanotechnology-based ophthalmic drugs currently on the market or still in clinical trials and the recent patents of nanocarriers. Finally, inspired by current trends and therapeutic concepts, we provide an insight into the challenges faced by novel ocular drug delivery systems and further put forward directions for future research. We hope this review can provide inspiration and motivation for better design and development of novel ophthalmic formulations.
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Affiliation(s)
- Shiding Li
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200011, China
| | - Liangbo Chen
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200011, China
| | - Yao Fu
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200011, China.
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Parsons NB, Annamalai B, Rohrer B. Regulatable Complement Inhibition of the Alternative Pathway Mitigates Wet Age-Related Macular Degeneration Pathology in a Mouse Model. Transl Vis Sci Technol 2023; 12:17. [PMID: 37462980 PMCID: PMC10362922 DOI: 10.1167/tvst.12.7.17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 06/19/2023] [Indexed: 07/21/2023] Open
Abstract
Purpose Risk for developing age-related macular degeneration (AMD) is linked to an overactive complement system. In the mouse model of laser-induced choroidal neovascularization (CNV), elevated levels of complement effector molecules, including complement C3, have been identified, and the alternative pathway (AP) is required for pathology. The main soluble AP regular is complement factor H (fH). We have previously shown that AP inhibition via subretinal AAV-mediated delivery of CR2-fH using a constitutive promoter is efficacious in reducing CNV. Here we ask whether the C3 promoter (pC3) effectively drives CR2-fH bioavailability for gene therapy. Methods Truncated pC3 was used to generate plasmids pC3-mCherry/CR2-fH followed by production of corresponding AAV5 vectors. pC3 activation was determined in transiently transfected ARPE-19 cells stimulated with H2O2 or normal human serum (+/- antioxidant or humanized CR2-fH, respectively). CNV was analyzed in C57BL/6J mice treated subretinally with AAV5-pC3-mCherry/CR2-fH using imaging (optical coherence tomography [OCT] and fundus imaging), functional (electroretinography [ERG]), and molecular (protein expression) readouts. Results Modulation of pC3 in vitro is complement and oxidative stress dependent, as shown by mCherry fluorescence. AAV5-pC3-CR2-fH were identified as safe and effective using OCT and ERG. CR2-fH expression significantly reduced CNV compared to mCherry and was correlated with reduced levels of C3dg/C3d in the retinal pigment epithelium/choroid fraction. Conclusions We conclude that complement-dependent regulation of AP inhibition ameliorates AMD pathology as effectively as using a constitutive promoter. Translational Relevance The goal of anticomplement therapy is to restore homeostatic levels of complement activation, which might be more easily achievable using a self-regulating system.
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Affiliation(s)
- Nathaniel B. Parsons
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, USA
| | | | - Bärbel Rohrer
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, USA
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA
- Ralph H. Johnson VA Medical Center, Division of Research, Charleston, SC, USA
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Sanie-Jahromi F, Nowroozzadeh MH. RPE based gene and cell therapy for inherited retinal diseases: A review. Exp Eye Res 2022; 217:108961. [DOI: 10.1016/j.exer.2022.108961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 01/19/2022] [Accepted: 01/20/2022] [Indexed: 11/29/2022]
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Vagni P, Perlini LE, Chenais NAL, Marchetti T, Parrini M, Contestabile A, Cancedda L, Ghezzi D. Gene Editing Preserves Visual Functions in a Mouse Model of Retinal Degeneration. Front Neurosci 2019; 13:945. [PMID: 31551698 PMCID: PMC6748340 DOI: 10.3389/fnins.2019.00945] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 08/21/2019] [Indexed: 02/05/2023] Open
Abstract
Inherited retinal dystrophies (IRDs) are a large and heterogeneous group of degenerative diseases caused by mutations in various genes. Given the favorable anatomical and immunological characteristics of the eye, gene therapy holds great potential for their treatment. Our goal is to validate the preservation of visual functions by viral-free homology directed repair (HDR) in an autosomal recessive loss of function mutation. We used a tailored gene editing system based on clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) to prevent retinal photoreceptor death in the retinal degeneration 10 (Rd10) mouse model of retinitis pigmentosa. We tested the gene editing tool in vitro and then used in vivo subretinal electroporation to deliver it to one of the retinas of mouse pups at different stages of photoreceptor differentiation. Three months after gene editing, the treated eye exhibited a higher visual acuity compared to the untreated eye. Moreover, we observed preservation of light-evoked responses both in explanted retinas and in the visual cortex of treated animals. Our study validates a CRISPR/Cas9-based therapy as a valuable new approach for the treatment of retinitis pigmentosa caused by autosomal recessive loss-of-function point mutations.
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Affiliation(s)
- Paola Vagni
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Laura E Perlini
- Laboratory of Local Micro-environment and Brain Development, Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Naïg A L Chenais
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Tommaso Marchetti
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Martina Parrini
- Laboratory of Local Micro-environment and Brain Development, Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Andrea Contestabile
- Laboratory of Local Micro-environment and Brain Development, Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Laura Cancedda
- Laboratory of Local Micro-environment and Brain Development, Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genoa, Italy.,Dulbecco Telethon Institute, Roma, Italy
| | - Diego Ghezzi
- Laboratory of Local Micro-environment and Brain Development, Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genoa, Italy
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Genome Editing as a Treatment for the Most Prevalent Causative Genes of Autosomal Dominant Retinitis Pigmentosa. Int J Mol Sci 2019; 20:ijms20102542. [PMID: 31126147 PMCID: PMC6567127 DOI: 10.3390/ijms20102542] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 05/15/2019] [Accepted: 05/22/2019] [Indexed: 02/07/2023] Open
Abstract
: Inherited retinal dystrophies (IRDs) are a clinically and genetically heterogeneous group of diseases with more than 250 causative genes. The most common form is retinitis pigmentosa. IRDs lead to vision impairment for which there is no universal cure. Encouragingly, a first gene supplementation therapy has been approved for an autosomal recessive IRD. However, for autosomal dominant IRDs, gene supplementation therapy is not always pertinent because haploinsufficiency is not the only cause. Disease-causing mechanisms are often gain-of-function or dominant-negative, which usually require alternative therapeutic approaches. In such cases, genome-editing technology has raised hopes for treatment. Genome editing could be used to i) invalidate both alleles, followed by supplementation of the wild type gene, ii) specifically invalidate the mutant allele, with or without gene supplementation, or iii) to correct the mutant allele. We review here the most prevalent genes causing autosomal dominant retinitis pigmentosa and the most appropriate genome-editing strategy that could be used to target their different causative mutations.
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Zhang W, Kim SM, Wang W, Cai C, Feng Y, Kong W, Lin X. Cochlear Gene Therapy for Sensorineural Hearing Loss: Current Status and Major Remaining Hurdles for Translational Success. Front Mol Neurosci 2018; 11:221. [PMID: 29997477 PMCID: PMC6028713 DOI: 10.3389/fnmol.2018.00221] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 06/06/2018] [Indexed: 12/19/2022] Open
Abstract
Sensorineural hearing loss (SNHL) affects millions of people. Genetic mutations play a large and direct role in both congenital and late-onset cases of SNHL (e.g., age-dependent hearing loss, ADHL). Although hearing aids can help moderate to severe hearing loss the only effective treatment for deaf patients is the cochlear implant (CI). Gene- and cell-based therapies potentially may preserve or restore hearing with more natural sound perception, since their theoretical frequency resolution power is much higher than that of cochlear implants. These biologically-based interventions also carry the potential to re-establish hearing without the need for implanting any prosthetic device; the convenience and lower financial burden afforded by such biologically-based interventions could potentially benefit far more SNHL patients. Recently major progress has been achieved in preclinical studies of cochlear gene therapy. This review critically evaluates recent advances in the preclinical trials of gene therapies for SNHL and the major remaining challenges for the development and eventual clinical translation of this novel therapy. The cochlea bears many similarities to the eye for translational studies of gene therapies. Experience gained in ocular gene therapy trials, many of which have advanced to clinical phase III, may provide valuable guidance in improving the chance of success for cochlear gene therapy in human trials. A discussion on potential implications of translational knowledge gleaned from large numbers of advanced clinical trials of ocular gene therapy is therefore included.
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Affiliation(s)
- Wenjuan Zhang
- Department of Otolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Sun Myoung Kim
- Department of Otolaryngology, Emory University School of Medicine, Atlanta, GA, United States
| | - Wenwen Wang
- Department of Otolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | | | - Yong Feng
- Xiangya School of Medicine, Changsha, China
| | - Weijia Kong
- Department of Otolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xi Lin
- Department of Otolaryngology, Emory University School of Medicine, Atlanta, GA, United States
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Burnight ER, Gupta M, Wiley LA, Anfinson KR, Tran A, Triboulet R, Hoffmann JM, Klaahsen DL, Andorf JL, Jiao C, Sohn EH, Adur MK, Ross JW, Mullins RF, Daley GQ, Schlaeger TM, Stone EM, Tucker BA. Using CRISPR-Cas9 to Generate Gene-Corrected Autologous iPSCs for the Treatment of Inherited Retinal Degeneration. Mol Ther 2017; 25:1999-2013. [PMID: 28619647 PMCID: PMC5589061 DOI: 10.1016/j.ymthe.2017.05.015] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 05/22/2017] [Accepted: 05/22/2017] [Indexed: 01/20/2023] Open
Abstract
Patient-derived induced pluripotent stem cells (iPSCs) hold great promise for autologous cell replacement. However, for many inherited diseases, treatment will likely require genetic repair pre-transplantation. Genome editing technologies are useful for this application. The purpose of this study was to develop CRISPR-Cas9-mediated genome editing strategies to target and correct the three most common types of disease-causing variants in patient-derived iPSCs: (1) exonic, (2) deep intronic, and (3) dominant gain of function. We developed a homology-directed repair strategy targeting a homozygous Alu insertion in exon 9 of male germ cell-associated kinase (MAK) and demonstrated restoration of the retinal transcript and protein in patient cells. We generated a CRISPR-Cas9-mediated non-homologous end joining (NHEJ) approach to excise a major contributor to Leber congenital amaurosis, the IVS26 cryptic-splice mutation in CEP290, and demonstrated correction of the transcript and protein in patient iPSCs. Lastly, we designed allele-specific CRISPR guides that selectively target the mutant Pro23His rhodopsin (RHO) allele, which, following delivery to both patient iPSCs in vitro and pig retina in vivo, created a frameshift and premature stop that would prevent transcription of the disease-causing variant. The strategies developed in this study will prove useful for correcting a wide range of genetic variants in genes that cause inherited retinal degeneration.
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Affiliation(s)
- Erin R Burnight
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Manav Gupta
- Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital and Dana-Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 01451, USA
| | - Luke A Wiley
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Kristin R Anfinson
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Audrey Tran
- Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital and Dana-Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 01451, USA
| | - Robinson Triboulet
- Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital and Dana-Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 01451, USA
| | - Jeremy M Hoffmann
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Darcey L Klaahsen
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Jeaneen L Andorf
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Chunhua Jiao
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Elliott H Sohn
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Malavika K Adur
- Department of Animal Sciences, Iowa State University, Ames, IA 50011, USA
| | - Jason W Ross
- Department of Animal Sciences, Iowa State University, Ames, IA 50011, USA
| | - Robert F Mullins
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - George Q Daley
- Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital and Dana-Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 01451, USA
| | - Thorsten M Schlaeger
- Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital and Dana-Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 01451, USA
| | - Edwin M Stone
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Budd A Tucker
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA.
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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.
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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
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Pensado A, Diaz-Corrales FJ, De la Cerda B, Valdés-Sánchez L, Del Boz AA, Rodriguez-Martinez D, García-Delgado AB, Seijo B, Bhattacharya SS, Sanchez A. Span poly-L-arginine nanoparticles are efficient non-viral vectors for PRPF31 gene delivery: An approach of gene therapy to treat retinitis pigmentosa. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2016; 12:2251-2260. [PMID: 27381066 DOI: 10.1016/j.nano.2016.06.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 05/31/2016] [Accepted: 06/16/2016] [Indexed: 12/21/2022]
Abstract
Retinitis pigmentosa (RP) is the most common cause of inherited blindness in adults. Mutations in the PRPF31 gene produce autosomal dominant RP (adRP). To date there are no effective treatments for this disease. The purpose of this study was to design an efficient non-viral vector for human PRPF31 gene delivery as an approach to treat this form of adRP. Span based nanoparticles were developed to mediate gene transfer in the subretinal space of a mouse model of adRP carrying a point mutation (A216P) in the Prpf31 gene. Funduscopic examination, electroretinogram, optomotor test and optical coherence tomography were conducted to further in vivo evaluate the safety and efficacy of the nanosystems developed. Span-polyarginine (SP-PA) nanoparticles were able to efficiently transfect the GFP and PRPF31 plasmid in mice retinas. Statistically significant improvement in visual acuity and retinal thickness were found in Prpf31A216P/+ mice treated with the SP-PA-PRPF31 nanomedicine.
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Affiliation(s)
- Andrea Pensado
- Department of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, Universidade de Santiago de Compostela, Campus Vida, Santiago de Compostela, Spain
| | - Francisco J Diaz-Corrales
- Department of Cell Therapy and Regenerative Medicine, Andalusian Molecular Biology and Regenerative Medicine Centre (CABIMER), Seville, Spain
| | - Berta De la Cerda
- Department of Cell Therapy and Regenerative Medicine, Andalusian Molecular Biology and Regenerative Medicine Centre (CABIMER), Seville, Spain
| | - Lourdes Valdés-Sánchez
- Department of Cell Therapy and Regenerative Medicine, Andalusian Molecular Biology and Regenerative Medicine Centre (CABIMER), Seville, Spain
| | - Ana Aramburu Del Boz
- Department of Cell Therapy and Regenerative Medicine, Andalusian Molecular Biology and Regenerative Medicine Centre (CABIMER), Seville, Spain
| | - Daniel Rodriguez-Martinez
- Department of Cell Therapy and Regenerative Medicine, Andalusian Molecular Biology and Regenerative Medicine Centre (CABIMER), Seville, Spain
| | - Ana B García-Delgado
- Department of Cell Therapy and Regenerative Medicine, Andalusian Molecular Biology and Regenerative Medicine Centre (CABIMER), Seville, Spain
| | - Begoña Seijo
- Department of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, Universidade de Santiago de Compostela, Campus Vida, Santiago de Compostela, Spain; Molecular Image Group, Health Research Institute-University Clinical Hospital of Santiago de Compostela (IDIS), Santiago de Compostela, Spain
| | - Shomi S Bhattacharya
- Department of Cell Therapy and Regenerative Medicine, Andalusian Molecular Biology and Regenerative Medicine Centre (CABIMER), Seville, Spain
| | - Alejandro Sanchez
- Department of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, Universidade de Santiago de Compostela, Campus Vida, Santiago de Compostela, Spain; Molecular Image Group, Health Research Institute-University Clinical Hospital of Santiago de Compostela (IDIS), Santiago de Compostela, Spain.
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12
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Leaderer D, Cashman SM, Kumar-Singh R. Adeno-associated virus mediated delivery of an engineered protein that combines the complement inhibitory properties of CD46, CD55 and CD59. J Gene Med 2016; 17:101-15. [PMID: 25917932 DOI: 10.1002/jgm.2829] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 03/10/2015] [Accepted: 04/22/2015] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND A variety of disorders are associated with the activation of complement. CD46, CD55 and CD59 are the major membrane associated regulators of complement on human cells. Previously, we have found that independent expression of CD55, CD46 or CD59 through gene transfer protects murine tissues against human complement mediated attack. In the present study, we investigated the potential of combining the complement regulatory properties of CD46, CD55 and CD59 into single gene products expressed from an adeno-associated virus (AAV) vector in a soluble non-membrane anchored form. METHODS Minigenes encoding the complement regulatory domains from CD46, CD55 and CD59 (SACT) or CD55 and CD59 (DTAC) were cloned into an AAV vector. The specific regulatory activity of each component of SACT and DTAC was measured in vitro. The recombinant AAV vectors were injected into the peritoneum of mice and the efficacy of the transgene products for being able to protect murine liver vasculature against human complement, specifically the membrane attack complex (MAC), was measured. RESULTS SACT and DTAC exhibited properties similar to CD46, CD55 and CD59 or CD55 and CD59, respectively, in vitro. AAV mediated delivery of SACT or DTAC protected murine liver vasculature from human MAC deposition by 63.2% and 56.7%, respectively. CONCLUSIONS When delivered to mice in vivo via an AAV vector, SACT and DTAC are capable of limiting human complement mediated damage. SACT and DTAC merit further study as potential therapies for complement mediated disorders when delivered via a gene therapy approach.
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Affiliation(s)
- Derek Leaderer
- Department of Developmental, Molecular and Chemical Biology, Program in Genetics, Sackler School of Graduate Biomedical Sciences, Tufts University School of Medicine, Boston, MA, USA
| | - Siobhan M Cashman
- Department of Developmental, Molecular and Chemical Biology, Program in Genetics, Sackler School of Graduate Biomedical Sciences, Tufts University School of Medicine, Boston, MA, USA
| | - Rajendra Kumar-Singh
- Department of Developmental, Molecular and Chemical Biology, Program in Genetics, Sackler School of Graduate Biomedical Sciences, Tufts University School of Medicine, Boston, MA, USA
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Zorzi GK, Párraga JE, Seijo B, Sanchez A. Comparison of different cationized proteins as biomaterials for nanoparticle-based ocular gene delivery. Colloids Surf B Biointerfaces 2015; 135:533-541. [DOI: 10.1016/j.colsurfb.2015.08.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 08/02/2015] [Accepted: 08/09/2015] [Indexed: 12/24/2022]
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Tischner C, Wenz T. Keep the fire burning: Current avenues in the quest of treating mitochondrial disorders. Mitochondrion 2015; 24:32-49. [DOI: 10.1016/j.mito.2015.06.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 06/18/2015] [Accepted: 06/24/2015] [Indexed: 12/18/2022]
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Treatment of ocular disorders by gene therapy. Eur J Pharm Biopharm 2014; 95:331-42. [PMID: 25536112 DOI: 10.1016/j.ejpb.2014.12.022] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 12/08/2014] [Accepted: 12/15/2014] [Indexed: 12/27/2022]
Abstract
Gene therapy to treat ocular disorders is still starting, and current therapies are primarily experimental, with most human clinical trials still in research state, although beginning to show encouraging results. Currently 33 clinical trials have been approved, are in progress, or have been completed. The most promising results have been obtained in clinical trials of ocular gene therapy for Leber Congenital Amaurosis, which have prompted the study of several ocular diseases that are good candidates to be treated with gene therapy: glaucoma, age-related macular degeneration, retinitis pigmentosa, or choroideremia. The success of gene therapy relies on the efficient delivery of the genetic material to target cells, achieving optimum long-term gene expression. Although viral vectors have been widely used, their potential risk associated mainly with immunogenicity and mutagenesis has promoted the design of non-viral vectors. In this review, the main administration routes and the most studied delivery systems, viral and non-viral, for ocular gene therapy are presented. The primary ocular disease candidates to be treated with gene therapy have been also reviewed, including the genetic basis and the most relevant preclinical and clinical studies.
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Cereso N, Pequignot MO, Robert L, Becker F, De Luca V, Nabholz N, Rigau V, De Vos J, Hamel CP, Kalatzis V. Proof of concept for AAV2/5-mediated gene therapy in iPSC-derived retinal pigment epithelium of a choroideremia patient. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2014; 1:14011. [PMID: 26015956 PMCID: PMC4362346 DOI: 10.1038/mtm.2014.11] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 02/24/2014] [Indexed: 02/06/2023]
Abstract
Inherited retinal dystrophies (IRDs) comprise a large group of genetically and clinically heterogeneous diseases that lead to progressive vision loss, for which a paucity of disease-mimicking animal models renders preclinical studies difficult. We sought to develop pertinent human cellular IRD models, beginning with choroideremia, caused by mutations in the CHM gene encoding Rab escort protein 1 (REP1). We reprogrammed REP1-deficient fibroblasts from a CHM-/y patient into induced pluripotent stem cells (iPSCs), which we differentiated into retinal pigment epithelium (RPE). This iPSC-derived RPE is a polarized monolayer with a classic morphology, expresses characteristic markers, is functional for fluid transport and phagocytosis, and mimics the biochemical phenotype of patients. We assayed a panel of adeno-associated virus (AAV) vector serotypes and showed that AAV2/5 is the most efficient at transducing the iPSC-derived RPE and that CHM gene transfer normalizes the biochemical phenotype. The high, and unmatched, in vitro transduction efficiency is likely aided by phagocytosis and mimics the scenario that an AAV vector encounters in vivo in the subretinal space. We demonstrate the superiority of AAV2/5 in the human RPE and address the potential of patient iPSC–derived RPE to provide a proof-of-concept model for gene replacement in the absence of an appropriate animal model.
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Affiliation(s)
- Nicolas Cereso
- Inserm U1051, Institute for Neurosciences of Montpellier , Montpellier, France ; University of Montpellier 1 , Montpellier, France ; University of Montpellier 2 , Montpellier, France
| | - Marie O Pequignot
- Inserm U1051, Institute for Neurosciences of Montpellier , Montpellier, France ; University of Montpellier 1 , Montpellier, France ; University of Montpellier 2 , Montpellier, France
| | - Lorenne Robert
- Inserm U1051, Institute for Neurosciences of Montpellier , Montpellier, France ; University of Montpellier 1 , Montpellier, France ; University of Montpellier 2 , Montpellier, France
| | - Fabienne Becker
- Inserm U1040, Institute for Research in Biotherapy , Montpellier, France
| | - Valerie De Luca
- Inserm U1051, Institute for Neurosciences of Montpellier , Montpellier, France ; University of Montpellier 1 , Montpellier, France ; University of Montpellier 2 , Montpellier, France
| | - Nicolas Nabholz
- Inserm U1051, Institute for Neurosciences of Montpellier , Montpellier, France ; University of Montpellier 1 , Montpellier, France ; University of Montpellier 2 , Montpellier, France ; Department of Ophthalmology, CHRU , Montpellier, France
| | - Valerie Rigau
- Department of Anatomy and Pathological Cytology, CHRU , Montpellier, France
| | - John De Vos
- University of Montpellier 1 , Montpellier, France ; University of Montpellier 2 , Montpellier, France ; Inserm U1040, Institute for Research in Biotherapy , Montpellier, France ; Cellular Therapy Unit, CHRU , Montpellier, France
| | - Christian P Hamel
- Inserm U1051, Institute for Neurosciences of Montpellier , Montpellier, France ; University of Montpellier 1 , Montpellier, France ; University of Montpellier 2 , Montpellier, France ; Department of Ophthalmology, CHRU , Montpellier, France ; Centre of Reference for Genetic Sensory Diseases, CHRU , Montpellier, France
| | - Vasiliki Kalatzis
- Inserm U1051, Institute for Neurosciences of Montpellier , Montpellier, France ; University of Montpellier 1 , Montpellier, France ; University of Montpellier 2 , Montpellier, France
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17
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Trapani I, Colella P, Sommella A, Iodice C, Cesi G, de Simone S, Marrocco E, Rossi S, Giunti M, Palfi A, Farrar GJ, Polishchuk R, Auricchio A. Effective delivery of large genes to the retina by dual AAV vectors. EMBO Mol Med 2014; 6:194-211. [PMID: 24150896 PMCID: PMC3927955 DOI: 10.1002/emmm.201302948] [Citation(s) in RCA: 182] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2013] [Revised: 10/10/2013] [Accepted: 10/14/2013] [Indexed: 01/10/2023] Open
Abstract
Retinal gene therapy with adeno-associated viral (AAV) vectors is safe and effective in humans. However, AAV's limited cargo capacity prevents its application to therapies of inherited retinal diseases due to mutations of genes over 5 kb, like Stargardt's disease (STGD) and Usher syndrome type IB (USH1B). Previous methods based on 'forced' packaging of large genes into AAV capsids may not be easily translated to the clinic due to the generation of genomes of heterogeneous size which raise safety concerns. Taking advantage of AAV's ability to concatemerize, we generated dual AAV vectors which reconstitute a large gene by either splicing (trans-splicing), homologous recombination (overlapping), or a combination of the two (hybrid). We found that dual trans-splicing and hybrid vectors transduce efficiently mouse and pig photoreceptors to levels that, albeit lower than those achieved with a single AAV, resulted in significant improvement of the retinal phenotype of mouse models of STGD and USH1B. Thus, dual AAV trans-splicing or hybrid vectors are an attractive strategy for gene therapy of retinal diseases that require delivery of large genes.
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Affiliation(s)
- Ivana Trapani
- Telethon Institute of Genetics and Medicine (TIGEM)Naples, Italy
| | | | - Andrea Sommella
- Telethon Institute of Genetics and Medicine (TIGEM)Naples, Italy
| | - Carolina Iodice
- Telethon Institute of Genetics and Medicine (TIGEM)Naples, Italy
| | - Giulia Cesi
- Telethon Institute of Genetics and Medicine (TIGEM)Naples, Italy
| | - Sonia de Simone
- Telethon Institute of Genetics and Medicine (TIGEM)Naples, Italy
| | - Elena Marrocco
- Telethon Institute of Genetics and Medicine (TIGEM)Naples, Italy
| | - Settimio Rossi
- Department of Ophthalmology, Second University of NaplesNaples, Italy
| | - Massimo Giunti
- Department of Veterinary Morphophysiology and Animal Production, University of BolognaBologna, Italy
| | - Arpad Palfi
- The School of Genetics & Microbiology, Trinity College DublinDublin, Ireland
| | - Gwyneth J Farrar
- The School of Genetics & Microbiology, Trinity College DublinDublin, Ireland
| | - Roman Polishchuk
- Telethon Institute of Genetics and Medicine (TIGEM)Naples, Italy
| | - Alberto Auricchio
- Telethon Institute of Genetics and Medicine (TIGEM)Naples, Italy
- Medical Genetics, Department of Translational Medicine, Federico II UniversityNaples, Italy
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18
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Martens TF, Vercauteren D, Forier K, Deschout H, Remaut K, Paesen R, Ameloot M, Engbersen JFJ, Demeester J, De Smedt SC, Braeckmans K. Measuring the intravitreal mobility of nanomedicines with single-particle tracking microscopy. Nanomedicine (Lond) 2013; 8:1955-68. [DOI: 10.2217/nnm.12.202] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Aim: To develop a robust assay to evaluate and compare the intravitreal mobility of nanoparticles in the intact vitreous body. Materials & methods: Excised bovine eyes were prepared to preserve the fragile structure of the vitreous humor, while permitting high-resolution fluorescence microscopy and single-particle tracking analysis of intravitreally injected nanoparticles. This assay was validated by analyzing polystyrene beads and further employed to evaluate gene nanomedicines composed of poly(amido amine)s and plasmid DNA. Results: The assay was able to distinguish immobilized cationic nanoparticles from mobile PEGylated nanoparticles. PEGylation of the polyplexes resulted in a drastic improvement of their mobility. Conclusion: An ex vivo eye model is presented for studying nanoparticle mobility in intact vitreous humor by single-particle tracking microscopy. These results give important guidelines for developing gene- and drug-delivery nanomedicines that are compatible with intravitreal administration. Original submitted 20 April 2012; Revised submitted 22 November 2012
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Affiliation(s)
- Thomas F Martens
- Laboratory for General Biochemistry & Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium
- Center for Nano- & Biophotonics (NB-Photonics), Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium
| | - Dries Vercauteren
- Laboratory for General Biochemistry & Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium
- Center for Nano- & Biophotonics (NB-Photonics), Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium
| | - Katrien Forier
- Laboratory for General Biochemistry & Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium
- Center for Nano- & Biophotonics (NB-Photonics), Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium
| | - Hendrik Deschout
- Laboratory for General Biochemistry & Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium
- Center for Nano- & Biophotonics (NB-Photonics), Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium
| | - Katrien Remaut
- Laboratory for General Biochemistry & Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium
| | - Rik Paesen
- University Hasselt & Transnational University Limburg, BIOMED, Agoralaan building C, B-3590 Diepenbeek, Belgium
| | - Marcel Ameloot
- University Hasselt & Transnational University Limburg, BIOMED, Agoralaan building C, B-3590 Diepenbeek, Belgium
| | - Johan FJ Engbersen
- Department of Biomedical Chemistry, MIRA Institute for Biomedical Technology & Technical Medicine, Faculty of Science & Technology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
| | - Jo Demeester
- Laboratory for General Biochemistry & Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium
| | - Stefaan C De Smedt
- Laboratory for General Biochemistry & Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium.
| | - Kevin Braeckmans
- Laboratory for General Biochemistry & Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium
- Center for Nano- & Biophotonics (NB-Photonics), Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium
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19
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Colella P, Auricchio A. Gene therapy of inherited retinopathies: a long and successful road from viral vectors to patients. Hum Gene Ther 2013; 23:796-807. [PMID: 22734691 DOI: 10.1089/hum.2012.123] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Inherited retinopathies (IRs) are common and untreatable blinding conditions inherited mostly as monogenic due to mutations in genes expressed in retinal photoreceptors (PRs) and in retinal pigment epithelium (RPE). Over the last two decades, the retina has emerged as one of the most favorable target tissues for gene therapy given its small size and its enclosed and immune-privileged environment. Different types of viral vectors have been developed, especially those based on the adeno-associated virus (AAV), which efficiently deliver therapeutic genes to PRs or RPE upon subretinal injections. Dozens of successful proofs of concept of the efficacy of gene therapy for recessive and dominant IRs have been generated in small and large models that have paved the way to the first clinical trials using AAV in patients with Leber congenital amaurosis, a severe form of childhood blindness. The results from these initial trials suggest that retinal gene therapy with AAV is safe in humans, that vision can be improved in patients that have suffered from severe impairment of visual function, in some cases for decades, and that readministration of AAV to the subretinal space is feasible, effective, and safe. However, none of the trials could match the levels of efficacy of gene therapy observed in a dog model of the disease, suggesting that there is room for improvement. In conclusion, these results bode well for further testing of AAV-mediated retinal gene therapy in patients with other monogenic and complex forms of blindness.
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20
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Chaplot SP, Rupenthal ID. Dendrimers for gene delivery – a potential approach for ocular therapy? J Pharm Pharmacol 2013; 66:542-56. [DOI: 10.1111/jphp.12104] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2013] [Accepted: 06/15/2013] [Indexed: 12/12/2022]
Abstract
Abstract
Objectives
A vast number of blinding diseases have genetic aetiologies and may be treated by molecular based therapies such as antisense oligonucleotides or short interfering RNA. However, treatment success of ocular gene therapy is highly dependent on efficient delivery of such molecules.
Key findings
The majority of clinical studies for ocular gene therapy utilize viral vectors. While these have proven highly efficient, they show limited loading capacity and pose significant safety risks owing to their oncogenic and immunogenic effects. Non-viral gene carriers have emerged as a promising alternative with dendrimers providing great potential for gene therapy because of their size, shape and high density of modifiable surface groups. However, while dendrimers have been used extensively for drug and gene delivery to other organs, only a few studies have been reported on the eye.
Summary
This review focuses on the development of dendrimers for gene delivery with special emphasis on ocular gene therapy. Different synthesis approaches and types of dendrimers are discussed. Ocular gene therapy targets are highlighted with an overview of current clinical studies. The use of dendrimers in ocular gene delivery in comparison to liposomes and nanoparticles is also discussed. Finally, future prospects of tailored multifunctional dendrimers for ocular gene therapy are highlighted.
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Affiliation(s)
- Sahil P Chaplot
- Drug Delivery Research Unit, School of Pharmacy, The University of Auckland, Auckland, New Zealand
| | - Ilva D Rupenthal
- Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand
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21
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Vaquer G, Rivière F, Mavris M, Bignami F, Llinares-Garcia J, Westermark K, Sepodes B. Animal models for metabolic, neuromuscular and ophthalmological rare diseases. Nat Rev Drug Discov 2013; 12:287-305. [PMID: 23493083 DOI: 10.1038/nrd3831] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Animal models are important tools in the discovery and development of treatments for rare diseases, particularly given the small populations of patients in which to evaluate therapeutic candidates. Here, we provide a compilation of mammalian animal models for metabolic, neuromuscular and ophthalmological orphan-designated conditions based on information gathered by the European Medicines Agency's Committee for Orphan Medicinal Products (COMP) since its establishment in 2000, as well as from a review of the literature. We discuss the predictive value of the models and their advantages and limitations with the aim of highlighting those that are appropriate for the preclinical evaluation of novel therapies, thereby facilitating further drug development for rare diseases.
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Affiliation(s)
- Guillaume Vaquer
- Human Medicines Special Areas, Human Medicines Development and Evaluation, European Medicines Agency, London E14 4HB, UK
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22
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Pescina S, Antopolsky M, Santi P, Nicoli S, Murtomäki L. Effect of iontophoresis on the in vitro trans-scleral transport of three single stranded oligonucleotides. Eur J Pharm Sci 2013; 49:142-7. [PMID: 23485440 DOI: 10.1016/j.ejps.2013.02.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 12/21/2012] [Accepted: 02/03/2013] [Indexed: 01/17/2023]
Abstract
Oligonucleotides represent a subject of clinical interest due to their potential ability to treat several diseases, including those affecting the posterior segment of the eye. Unfortunately, therapeutic oligonucleotides are currently administered by means of highly invasive approaches, such as intravitreal injections. The aim of the present work was to study in vitro, across isolated bovine sclera, the effect of iontophoresis on the transport of three single stranded oligonucleotides (ssDNA), 12-, 24- and 36-mer, selected as reference compounds in view of a non-invasive drug delivery to the back of the eye. All the three sequences were able to cross bovine sclera in vitro without iontophoresis. When anodal iontophoresis was applied, no change in flux was observed, while in the presence of cathodal iontophoresis the permeability coefficients increased four-fold compared to passive conditions. This behavior can be ascribed to the electrorepulsive mechanism, due to the negative charge of the nucleic acid backbone. It was also observed that the molecular weights of the three sequences did not affect trans-scleral transport, neither in passive, nor in current assisted permeation. Furthermore, increasing the current intensity from 1.75 mA to 3 mA, no effect on the trans-scleral transport of the 24-mer was noticed. Although preliminary, the results demonstrate that cathodal iontophoresis enhances trans-scleral transport of single stranded oligonucleotides and suggest its use as a novel non-invasive approach for the treatment of diseases affecting the posterior segment of the eye.
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Affiliation(s)
- Silvia Pescina
- Department of Pharmacy, University of Parma, Parco Area delle Scienze 27/A, 43124 Parma, Italy
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Abstract
Over 200 hereditary diseases have been identified and reported in the cat, several of which affect the eye, with homology to human hereditary disease. Compared with traditional murine models, the cat demonstrates more features in common with humans, including many anatomic and physiologic similarities, longer life span, increased size, and a genetically more heterogeneous background. The development of genomic resources in the cat has facilitated mapping and further characterization of feline models. During recent years, the wealth of knowledge in feline ophthalmology and neurophysiology has been extended to include new diseases of significant interest for comparative ophthalmology. This makes the cat an extremely valuable animal species to utilize for further research into disease processes affecting both cats and humans. This is especially true in the advancement and study of new treatment regimens and for extended therapeutic trials. Groups of feline eye diseases reviewed in the following are lysosomal storage disorders, congenital glaucoma, and neuroretinal degenerations. Each has important implications for human ophthalmic research.
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Affiliation(s)
- Kristina Narfström
- Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, Missouri 65201;
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Photoreceptor degeneration in mice: adeno-associated viral vector-mediated delivery of erythropoietin. Methods Mol Biol 2013; 982:237-63. [PMID: 23456874 DOI: 10.1007/978-1-62703-308-4_16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The exogenous delivery of erythropoietin (EPO) and EPO derivatives (EPO-Ds) represents a valuable strategy to protect the retina from degeneration. In this chapter we describe a method to deliver EPO and the EPO derivative S100E in the light-damage model of induced retinal degeneration using adeno--associated viral (AAV) vectors and to evaluate the functional and morphological protection of the retina from light damage.
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Tarallo V, Bogdanovich S, Hirano Y, Tudisco L, Zentilin L, Giacca M, Ambati J, De Falco S. Inhibition of choroidal and corneal pathologic neovascularization by Plgf1-de gene transfer. Invest Ophthalmol Vis Sci 2012; 53:7989-96. [PMID: 23139276 DOI: 10.1167/iovs.12-10658] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
PURPOSE Ocular neovascularization (NV), the primary cause of blindness, typically is treated via inhibition of VEGF-A activity. However, besides VEGF-A, other proteins of the same family, including VEGF-B and placental growth factor (PlGF, all together VEGFs), have a crucial role in the angiogenesis process. PlGF and VEGF, which form heterodimers if co-expressed, both are required for pathologic angiogenesis. We generated a PlGF1 variant, named PlGF1-DE, which is unable to bind and activate VEGFR-1, but retains the ability to form heterodimer. PlGF1-DE acts as dominant negative of VEGF-A and PlGF1wt through heterodimerization mechanism. The purpose of our study was to explore the therapeutic potential of Plgf1-de gene in choroid and cornea NV context. METHODS In the model of laser-induced choroidal neovascularization (CNV), Plgf1-de gene, and as control Plgf1wt, LacZ, or gfp genes, were delivered using adeno-associated virus (AAV) vector by subretinal injection 14 days before the injury. After 7 days CNV volume was assessed. Corneal NV was induced by scrape or suture procedures. Expression vectors for PlGF1wt or PlGF1-DE, and as control the empty vector pCDNA3, were injected in the mouse cornea after the vascularization insults. NV was evaluated with CD31 and LYVE-1 immunostaining. RESULTS The expression of Plgf1-de induced significant inhibition of choroidal and corneal NV by reducing VEGF-A homodimer production. Conversely, the delivery of Plgf1wt, despite induced similar reduction of VEGF-A production, did not affect NV. CONCLUSIONS Plgf1-de gene is a new therapeutic tool for the inhibition of VEGFs driven ocular NV.
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Affiliation(s)
- Valeria Tarallo
- Angiogenesis Lab, Institute of Genetics and Biophysics, CNR, Naples, Italy
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Shao J, Tian L, Lei B, Wei L, Yang Y, Kijlstra A, Yang P. AAV2-mediated subretinal gene transfer of mIL-27p28 attenuates experimental autoimmune uveoretinitis in mice. PLoS One 2012; 7:e37773. [PMID: 22629453 PMCID: PMC3358269 DOI: 10.1371/journal.pone.0037773] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Accepted: 04/27/2012] [Indexed: 11/28/2022] Open
Abstract
Background Advances in gene transfer techniques have provided long-term, safe and stable transduction of retinal cells following subretinal injection with adeno-associated viral (AAV) vectors. In this study we investigated whether subretinal injection of AAV2-murine IL-27p28 vector was effective in inhibiting experimental autoimmune uveoretinitis (EAU) induced in B10RIII mice. Methodology/Principal Findings An AAV2 vector encoding the murine IL-27p28 gene (rAAV2-CMV-mIL-27p28) was prepared and subretinally injected into B10RIII mice (4.35×108 vector genome (v.g.)). AAV2 vector mediating green fluorescent protein (rAAV2-CMV-GFP) served as a control (5×108 v.g.). The concentration of mIL-27p28 in homogenized eyes and serum was assayed by enzyme linked immunosorbent assay (ELISA) after subretinal injection. Human IRBP161–180 peptide and Complete Freund’s Adjuvant were injected into mice receiving either the rAAV2-CMV-mIL-27p28 or rAAV2-CMV-GFP vector. EAU was evaluated clinically and pathologically. The level of IL-17 and IL-10 in homogenized eyes was measured on day 12 and day 21 following immunization. Delayed type hypersensitivity (DTH) and IRBP161–180–specific proliferation of lymphocytes from the spleen and lymph nodes were assayed to examine the influence of the subretinal delivery of rAAV2-CMV-mIL-27p28 on the systemic immune response. IL-27p28 was detectable by ELISA within the eyes from two weeks following subretinal injection of the rAAV2-CMV-mIL-27p28 vector and showed a sustained high expression from day 14 to 9 months with a highest expression at 5 months. Subretinal injection of the vector significantly attenuated the severity of EAU disease clinically and pathologically in association with a significantly decreased IL-17 expression and an increased IL-10 expression. The IL-27p28 vector did not affect the systemic immune response, as determined by DTH and IRBP161–180–specific lymphocyte proliferation. Conclusions/Significance A high and stable expression of IL-27p28 was observed for at least 9 months following subretinal delivery of rAAV2-CMV-mIL-27p28. The amelioration of EAU disease severity was associated with a decreased IL-17 expression and an increased IL-10 expression.
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Affiliation(s)
- Ju Shao
- Chongqing Key Laboratory of Ophthalmology, Chongqing Eye Institute, Chongqing Medical University, The First Affiliated Hospital, Chongqing, People’s Republic of China
| | - Lichun Tian
- Chongqing Key Laboratory of Ophthalmology, Chongqing Eye Institute, Chongqing Medical University, The First Affiliated Hospital, Chongqing, People’s Republic of China
| | - Bo Lei
- Chongqing Key Laboratory of Ophthalmology, Chongqing Eye Institute, Chongqing Medical University, The First Affiliated Hospital, Chongqing, People’s Republic of China
| | - Lin Wei
- Chongqing Key Laboratory of Ophthalmology, Chongqing Eye Institute, Chongqing Medical University, The First Affiliated Hospital, Chongqing, People’s Republic of China
| | - Yan Yang
- Chongqing Key Laboratory of Ophthalmology, Chongqing Eye Institute, Chongqing Medical University, The First Affiliated Hospital, Chongqing, People’s Republic of China
| | - Aize Kijlstra
- Eye Research Institute Maastricht, Department of Ophthalmology, University Hospital Maastricht, Maastricht, The Netherlands
| | - Peizeng Yang
- Chongqing Key Laboratory of Ophthalmology, Chongqing Eye Institute, Chongqing Medical University, The First Affiliated Hospital, Chongqing, People’s Republic of China
- * E-mail:
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Delgado D, del Pozo-Rodríguez A, Solinís MÁ, Avilés-Triqueros M, Weber BHF, Fernández E, Gascón AR. Dextran and protamine-based solid lipid nanoparticles as potential vectors for the treatment of X-linked juvenile retinoschisis. Hum Gene Ther 2012; 23:345-55. [PMID: 22295905 DOI: 10.1089/hum.2011.115] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The goal of the present study was to analyze the potential application of nonviral vectors based on solid lipid nanoparticles (SLN) for the treatment of ocular diseases by gene therapy, specifically X-linked juvenile retinoschisis (XLRS). Vectors were prepared with SLN, dextran, protamine, and a plasmid (pCMS-EGFP or pCEP4-RS1). Formulations were characterized and the in vitro transfection capacity as well as the cellular uptake and the intracellular trafficking were studied in ARPE-19 cells. Formulations were also tested in vivo in Wistar rat eyes, and the efficacy was studied by monitoring the expression of enhanced green fluorescent protein (EGFP) after intravitreal, subretinal, and topical administration. The presence of dextran and protamine in the SLN improved greatly the expression of retinoschisin and EGFP in ARPE-19 cells. The nuclear localization signals of protamine, its ability to protect the DNA, and a shift in the entry mechanism from caveola-mediated to clathrin-mediated endocytosis promoted by the dextran, justify the increase in transfection. After ocular administration of the dextran-protamine-DNA-SLN complex to rat eyes, we detected the expression of EGFP in various types of cells depending on the administration route. Our vectors were also able to transfect corneal cells after topical application. We have demonstrated the potential usefulness of our nonviral vectors loaded with XLRS1 plasmid and provided evidence for their potential application for the management or treatment of degenerative retinal disorders as well as ocular surface diseases.
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Affiliation(s)
- Diego Delgado
- Pharmacokinetics, Nanotechnology and Gene Therapy Group Laboratory of Pharmacy and Pharmaceutical Technology, University of the Basque Country UPV/EHU, 01006 Vitoria-Gasteiz, Spain
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Bouaita A, Augustin S, Lechauve C, Cwerman-Thibault H, Bénit P, Simonutti M, Paques M, Rustin P, Sahel JA, Corral-Debrinski M. Downregulation of apoptosis-inducing factor in Harlequin mice induces progressive and severe optic atrophy which is durably prevented by AAV2-AIF1 gene therapy. ACTA ACUST UNITED AC 2011; 135:35-52. [PMID: 22120150 DOI: 10.1093/brain/awr290] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The Harlequin mutant mouse, characterized by loss of function of apoptosis-inducing factor, represents a reliable genetic model that resembles pathologies caused by human mitochondrial complex I deficiency. Therefore, we extensively characterized the retinal morphology and function of Harlequin mice during the course of neuronal cell death leading to blindness, with the aim of preventing optic atrophy. Retinas and optic nerves from these mice showed an isolated respiratory chain complex I defect correlated with retinal ganglion cell loss, optic atrophy, glial and microglial cell activation. All of these changes led to irreversible vision loss. In control mice, retinas AIF1 messenger RNA was 2.3-fold more abundant than AIF2, both messenger RNAs being sorted to the mitochondrial surface. In Harlequin mouse retinas, there was a 96% decrease of both AIF1 and AIF2 messenger RNA steady-state levels. We attained substantial and long-lasting protection of retinal ganglion cell and optic nerve integrity, the preservation of complex I function in optic nerves, as well as the prevention of glial and microglial responses after intravitreal administration of an AAV2 vector containing the full-length open reading frame and the 3' untranslated region of the AIF1 gene. Therefore, we demonstrate that gene therapy for mitochondrial diseases due to mutations in nuclear DNA can be achieved, so long as the 'therapeutic gene' permits the accurate cellular localization of the corresponding messenger RNA.
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Khar RK, Jain GK, Warsi MH, Mallick N, Akhter S, Pathan SA, Ahmad FJ. Nano-vectors for the Ocular Delivery of Nucleic Acid-based Therapeutics. Indian J Pharm Sci 2011; 72:675-88. [PMID: 21969738 PMCID: PMC3178967 DOI: 10.4103/0250-474x.84575] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 10/10/2010] [Indexed: 12/31/2022] Open
Abstract
Nucleic acid-based therapeutics have gained a lot of interest for the treatment of diverse ophthalmic pathologies. The first to enter in clinic has been an oligonucleotide, Vitravene® for the treatment of cytomegalovirus infection. More recently, research on aptamers for the treatment of age related macular degeneration has led to the development of Macugen®. Despite intense potential, effective ocular delivery of nucleic acids is a major challenge since therapeutic targets for nucleic acid-based drugs are mainly located in the posterior eye segment, requiring repeated invasive administration. Of late, nanotechnology-based nano-vectors have been developed in order to overcome the drawbacks of viral and other non-viral vectors. The diversity of nano-vectors allows for ease of use, flexibility in application, low-cost of production, higher transfection efficiency and enhanced genomic safety. Using nano-vector strategies, nucleic acids can be delivered either encapsulated or complexed with cationic lipids, polymers or peptides forming sustained release systems, which can be tailored according to the ocular tissue being targeted. The present review focuses on developments and advances in various nano-vectors for the ocular delivery of nucleic acid-based therapeutics, the barriers that such delivery systems face and methods to overcome them.
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Affiliation(s)
- R K Khar
- Department of Pharmaceutics, Faculty of Pharmacy, Jamia Hamdard, New Delhi - 110 062, India
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30
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Takakubo Y, Konttinen YT. Immune-regulatory mechanisms in systemic autoimmune and rheumatic diseases. Clin Dev Immunol 2011; 2012:941346. [PMID: 22110541 PMCID: PMC3207139 DOI: 10.1155/2012/941346] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Revised: 08/06/2011] [Accepted: 08/18/2011] [Indexed: 02/07/2023]
Abstract
Systemic autoimmune and rheumatic diseases (SAIRDs) are thought to develop due to the failure of autoimmune regulation and tolerance. Current therapies, such as biologics, have improved the clinical results of SAIRDs; however, they are not curative treatments. Recently, new discoveries have been made in immune tolerance and inflammation, such as tolerogenic dendritic cells, regulatory T and B cells, Th 17 cells, inflammatory and tolerogenic cytokines, and intracellular signaling pathways. They lay the foundation for the next generation of the therapies beyond the currently used biologic therapies. New drugs should target the core processes involved in disease mechanisms with the aim to attain complete cure combined with safety and low costs compared to the biologic agents. Re-establishment of autoimmune regulation and tolerance in SAIRDs by the end of the current decade should be the final and realistic target.
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Affiliation(s)
- Yuya Takakubo
- Department of Medicine, Biomedicum Helsinki, University of Helsinki, PO Box 700, Haartmaninkatu 8, 00029 HUS, Finland.
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31
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Karali M, Manfredi A, Puppo A, Marrocco E, Gargiulo A, Allocca M, Corte MD, Rossi S, Giunti M, Bacci ML, Simonelli F, Surace EM, Banfi S, Auricchio A. MicroRNA-restricted transgene expression in the retina. PLoS One 2011; 6:e22166. [PMID: 21818300 PMCID: PMC3144214 DOI: 10.1371/journal.pone.0022166] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Accepted: 06/16/2011] [Indexed: 12/19/2022] Open
Abstract
Background Gene transfer using adeno-associated viral (AAV) vectors has been successfully applied in the retina for the treatment of inherited retinal dystrophies. Recently, microRNAs have been exploited to fine-tune transgene expression improving therapeutic outcomes. Here we evaluated the ability of retinal-expressed microRNAs to restrict AAV-mediated transgene expression to specific retinal cell types that represent the main targets of common inherited blinding conditions. Methodology/Principal Findings To this end, we generated AAV2/5 vectors expressing EGFP and containing four tandem copies of miR-124 or miR-204 complementary sequences in the 3′UTR of the transgene expression cassette. These vectors were administered subretinally to adult C57BL/6 mice and Large White pigs. Our results demonstrate that miR-124 and miR-204 target sequences can efficiently restrict AAV2/5-mediated transgene expression to retinal pigment epithelium and photoreceptors, respectively, in mice and pigs. Interestingly, transgene restriction was observed at low vector doses relevant to therapy. Conclusions We conclude that microRNA-mediated regulation of transgene expression can be applied in the retina to either restrict to a specific cell type the robust expression obtained using ubiquitous promoters or to provide an additional layer of gene expression regulation when using cell-specific promoters.
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Affiliation(s)
- Marianthi Karali
- Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy
| | - Anna Manfredi
- Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy
| | - Agostina Puppo
- Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy
| | - Elena Marrocco
- Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy
| | | | | | | | - Settimio Rossi
- Department of Ophthalmology, Second University of Naples, Naples, Italy
| | - Massimo Giunti
- Department of Veterinary Medical Science (DSMVET), University of Bologna, Bologna, Italy
| | - Maria Laura Bacci
- Department of Veterinary Medical Science (DSMVET), University of Bologna, Bologna, Italy
| | - Francesca Simonelli
- Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy
- Department of Ophthalmology, Second University of Naples, Naples, Italy
| | | | - Sandro Banfi
- Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy
- Medical Genetics, Department of General Pathology, Second University of Naples, Naples, Italy
- * E-mail: (AA); (SB)
| | - Alberto Auricchio
- Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy
- Medical Genetics, Department of Pediatrics, University of Naples Federico II, Naples, Italy
- * E-mail: (AA); (SB)
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Abstract
The eye is an easily accessible, highly compartmentalised and immune-privileged organ that offers unique advantages as a gene therapy target. Significant advancements have been made in understanding the genetic pathogenesis of ocular diseases, and gene replacement and gene silencing have been implicated as potentially efficacious therapies. Recent improvements have been made in the safety and specificity of vector-based ocular gene transfer methods. Proof-of-concept for vector-based gene therapies has also been established in several experimental models of human ocular diseases. After nearly two decades of ocular gene therapy research, preliminary successes are now being reported in phase 1 clinical trials for the treatment of Leber congenital amaurosis. This review describes current developments and future prospects for ocular gene therapy. Novel methods are being developed to enhance the performance and regulation of recombinant adeno-associated virus- and lentivirus-mediated ocular gene transfer. Gene therapy prospects have advanced for a variety of retinal disorders, including retinitis pigmentosa, retinoschisis, Stargardt disease and age-related macular degeneration. Advances have also been made using experimental models for non-retinal diseases, such as uveitis and glaucoma. These methodological advancements are critical for the implementation of additional gene-based therapies for human ocular diseases in the near future.
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Affiliation(s)
- Melissa M Liu
- Immunopathology Section, Laboratory of Immunology, National Eye Institute, National Institutes of Health, 10 Center Drive, Bldg 10, Rm 10N103, NIH/NEI, Bethesda, MD 20895-1857, USA
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33
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Colella P, Iodice C, Di Vicino U, Annunziata I, Surace EM, Auricchio A. Non-erythropoietic erythropoietin derivatives protect from light-induced and genetic photoreceptor degeneration. Hum Mol Genet 2011; 20:2251-62. [PMID: 21421996 PMCID: PMC3090200 DOI: 10.1093/hmg/ddr115] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 03/01/2011] [Accepted: 03/15/2011] [Indexed: 11/21/2022] Open
Abstract
Given the high genetic heterogeneity of inherited retinal degenerations (IRDs), a wide applicable treatment would be desirable to halt/slow progressive photoreceptor (PR) cell loss in a mutation-independent manner. In addition to its erythropoietic activity, erythropoietin (EPO) presents neurotrophic characteristics. We have previously shown that adeno-associated viral (AAV) vector-mediated systemic EPO delivery protects from PR degeneration. However, this is associated with an undesired hematocrit increase that could contribute to PR protection. Non-erythropoietic EPO derivatives (EPO-D) are available which allow us to dissect erythropoiesis's role in PR preservation and may be more versatile and safe than EPO as anti-apoptotic agents. We delivered in animal models of light-induced or genetic retinal degeneration either intramuscularly or subretinally AAV vectors encoding EPO or one of the three selected EPO-D: the mutant S100E, the helix A- and B-derived EPO-mimetic peptides. We observed that (i) systemic expression of S100E induces a significantly lower hematocrit increase than EPO and provides similar protection from PR degeneration, and (ii) intraocular expression of EPO-D protects PR from degeneration in the absence of significant hematocrit increase. On the basis of this, we conclude that erythropoiesis is not required for EPO-mediated PR protection. However, the lower efficacy observed when EPO or S100E is expressed intraocularly rather than systemically suggests that hormone systemic effects contribute to PR protection. Unlike S100E, EPO-mimetic peptides preserve PR only when given locally, suggesting that different EPO-D have a different potency or mode of action. In conclusion, our data show that subretinal delivery of AAV vectors encoding EPO-D protects from light-induced and genetic PR degeneration.
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Affiliation(s)
- Pasqualina Colella
- Telethon Institute of Genetics and Medicine (TIGEM), 80131 Naples, Italy
- The Open University, Milton Keynes, UK and
| | - Carolina Iodice
- Telethon Institute of Genetics and Medicine (TIGEM), 80131 Naples, Italy
| | - Umberto Di Vicino
- Telethon Institute of Genetics and Medicine (TIGEM), 80131 Naples, Italy
| | - Ida Annunziata
- Telethon Institute of Genetics and Medicine (TIGEM), 80131 Naples, Italy
| | - Enrico M. Surace
- Telethon Institute of Genetics and Medicine (TIGEM), 80131 Naples, Italy
| | - Alberto Auricchio
- Telethon Institute of Genetics and Medicine (TIGEM), 80131 Naples, Italy
- Medical Genetics, Department of Pediatrics, Federico II University, Naples, Italy
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34
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Tian L, Yang P, Lei B, Shao J, Wang C, Xiang Q, Wei L, Peng Z, Kijlstra A. AAV2-mediated subretinal gene transfer of hIFN-α attenuates experimental autoimmune uveoretinitis in mice. PLoS One 2011; 6:e19542. [PMID: 21611186 PMCID: PMC3096632 DOI: 10.1371/journal.pone.0019542] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2010] [Accepted: 03/31/2011] [Indexed: 11/18/2022] Open
Abstract
Background Recent reports show that gene therapy may provide a long-term, safe and
effective intervention for human diseases. In this study, we investigated
the effectiveness of adeno-associated virus 2 (AAV2) based human
interferon-alpha (hIFN-α) gene therapy in experimental autoimmune
uveoretinitis (EAU), a classic model for human uveitis. Methodology/Principal Findings An AAV2 vector harboring the hIFN-α gene (AAV2.hIFN-α) was
subretinally injected into B10RIII mice at two doses
(1.5×106 vg, 1.5×108 vg). AAV2 vector
encoding green fluorescent protein (AAV2.GFP) was used as a control
(5×108 vg). The expression of hIFN-α in homogenized
eyes and serum was detected by ELISA three weeks after injection. The
biodistribution of vector DNA in the injected eyes, contralateral eyes and
distant organs was determined by PCR. EAU was induced by immunization with
IRBP161–180 three weeks following vector injections,
and evaluated clinically and pathologically. IRBP-specific proliferation and
IL-17 expression of lymphocytes from the spleen and lymph nodes were assayed
to test the influence of the subretinal delivery of AAV2.hIFN-α on the
systemic immune response. hIFN-α was effectively expressed in the eyes
from three weeks to three months following subretinal injection of
AAV2.hIFN-α vector. DNA of AAV2.GFP was observed only in the injected
eyes, but not in the distant organs or contralateral eyes. Subretinal
injection of both doses significantly attenuated EAU activity clinically and
histologically. For the lower dose, there was no difference concerning
lymphocyte proliferation and IL-17 production among the AAV2.hIFN-α,
AAV2.GFP and PBS injected mice. However, the higher dose of AAV2.hIFN-α
significantly suppressed lymphocyte proliferation and IL-17 production. Conclusions/Significance Subretinal delivery of AAV2.hIFN-α lead to an effective expression within
the eye for at least three months and significantly attenuated EAU activity.
AAV2.hIFN-α was shown to inhibit the systemic IRBP-specific immune
response.
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Affiliation(s)
- Lichun Tian
- Zhongshan Ophthalmic Center, Sun Yat-sen
University, Guangzhou, People's Republic of China
- The First Affiliated Hospital of Chongqing
Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye
Institute, Chongqing, People's Republic of China
| | - Peizeng Yang
- The First Affiliated Hospital of Chongqing
Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye
Institute, Chongqing, People's Republic of China
- * E-mail:
| | - Bo Lei
- The First Affiliated Hospital of Chongqing
Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye
Institute, Chongqing, People's Republic of China
| | - Ju Shao
- The First Affiliated Hospital of Chongqing
Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye
Institute, Chongqing, People's Republic of China
| | - Chaokui Wang
- The First Affiliated Hospital of Chongqing
Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye
Institute, Chongqing, People's Republic of China
| | - Qin Xiang
- The First Affiliated Hospital of Chongqing
Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye
Institute, Chongqing, People's Republic of China
| | - Lin Wei
- The First Affiliated Hospital of Chongqing
Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye
Institute, Chongqing, People's Republic of China
| | - Zhougui Peng
- The First Affiliated Hospital of Chongqing
Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye
Institute, Chongqing, People's Republic of China
| | - Aize Kijlstra
- Eye Research Institute Maastricht, Department
of Ophthalmology, University Hospital Maastricht, Maastricht, The
Netherlands
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35
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Abstract
The eye is an easily accessible, highly compartmentalised and immune-privileged organ that offers unique advantages as a gene therapy target. Significant advancements have been made in understanding the genetic pathogenesis of ocular diseases, and gene replacement and gene silencing have been implicated as potentially efficacious therapies. Recent improvements have been made in the safety and specificity of vector-based ocular gene transfer methods. Proof-of-concept for vector-based gene therapies has also been established in several experimental models of human ocular diseases. After nearly two decades of ocular gene therapy research, preliminary successes are now being reported in phase 1 clinical trials for the treatment of Leber congenital amaurosis. This review describes current developments and future prospects for ocular gene therapy. Novel methods are being developed to enhance the performance and regulation of recombinant adeno-associated virus- and lentivirus-mediated ocular gene transfer. Gene therapy prospects have advanced for a variety of retinal disorders, including retinitis pigmentosa, retinoschisis, Stargardt disease and age-related macular degeneration. Advances have also been made using experimental models for non-retinal diseases, such as uveitis and glaucoma. These methodological advancements are critical for the implementation of additional gene-based therapies for human ocular diseases in the near future.
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Affiliation(s)
- Melissa M Liu
- Immunopathology Section, Laboratory of Immunology, NIH/NEI, Bethesda, MD 20895-1857, USA
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36
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Cashman SM, Ramo K, Kumar-Singh R. A non membrane-targeted human soluble CD59 attenuates choroidal neovascularization in a model of age related macular degeneration. PLoS One 2011; 6:e19078. [PMID: 21552568 PMCID: PMC3084256 DOI: 10.1371/journal.pone.0019078] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Accepted: 03/24/2011] [Indexed: 01/06/2023] Open
Abstract
Age related macular degeneration (AMD) is the most common cause of blindness amongst the elderly. Approximately 10% of AMD patients suffer from an advanced form of AMD characterized by choroidal neovascularization (CNV). Recent evidence implicates a significant role for complement in the pathogenesis of AMD. Activation of complement terminates in the incorporation of the membrane attack complex (MAC) in biological membranes and subsequent cell lysis. Elevated levels of MAC have been documented on choroidal blood vessels and retinal pigment epithelium (RPE) of AMD patients. CD59 is a naturally occurring membrane bound inhibitor of MAC formation. Previously we have shown that membrane bound human CD59 delivered to the RPE cells of mice via an adenovirus vector can protect those cells from human complement mediated lysis ex vivo. However, application of those observations to choroidal blood vessels are limited because protection from MAC- mediated lysis was restricted only to the cells originally transduced by the vector. Here we demonstrate that subretinal delivery of an adenovirus vector expressing a transgene for a soluble non-membrane binding form of human CD59 can attenuate the formation of laser-induced choroidal neovascularization and murine MAC formation in mice even when the region of vector delivery is distal to the site of laser induced CNV. Furthermore, this same recombinant transgene delivered to the intravitreal space of mice by an adeno-associated virus vector (AAV) can also attenuate laser-induced CNV. To our knowledge, this is the first demonstration of a non-membrane targeting CD59 having biological potency in any animal model of disease in vivo. We propose that the above approaches warrant further exploration as potential approaches for alleviating complement mediated damage to ocular tissues in AMD.
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Affiliation(s)
- Siobhan M. Cashman
- Department of Ophthalmology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Kasmir Ramo
- Department of Ophthalmology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Rajendra Kumar-Singh
- Department of Ophthalmology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
- * E-mail:
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37
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Zorzi GK, Párraga JE, Seijo B, Sánchez A. Hybrid Nanoparticle Design Based on Cationized Gelatin and the Polyanions Dextran Sulfate and Chondroitin Sulfate for Ocular Gene Therapy. Macromol Biosci 2011; 11:905-13. [DOI: 10.1002/mabi.201100005] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Indexed: 12/23/2022]
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Abstract
Dendritic cells (DCs) play a pivotal role in regulating the balance between immunity and tolerance of the immune system. Recent advancements in DC biology and techniques for manipulating the function of these cells have shown their immense therapeutic potential for treating a variety of immune disorders. Theoretically, antigen-specific tolerogenic DCs can be generated in vitro and delivered to patients to correct the dysfunctional immune responses that attack their own tissues or over-react to innocuous foreign antigens. However, DCs are a heterogeneous population of cells with differences in cell surface makers, differentiation pathways and functions. Studies are needed to examine which subset of DCs can be used for what type of applications. Furthermore, most of the information on tolerogenic DCs has been obtained from animal models and translational studies are needed to examine how a DC therapeutic strategy can be implemented clinically to modulate immunity.
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Affiliation(s)
- Jim Hu
- Physiology and Experimental Medicine Research Program, Hospital for Sick Children, 555 University Avenue, Toronto, ON, Canada.
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39
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Touchard E, Kowalczuk L, Bloquel C, Naud MC, Bigey P, Behar-Cohen F. The ciliary smooth muscle electrotransfer: basic principles and potential for sustained intraocular production of therapeutic proteins. J Gene Med 2010; 12:904-19. [DOI: 10.1002/jgm.1517] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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40
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Ponder KP, Auricchio A. Gene therapy for ocular problems in mucopolysaccharidosis: an experimental and promising approach with benefits in animal models - a review. Clin Exp Ophthalmol 2010. [DOI: 10.1111/j.1442-9071.2010.02367.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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41
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Sodi A, Caputo R, Passerini I, Bacci GM, Menchini U. Novel RDH12 sequence variations in Leber congenital amaurosis. J AAPOS 2010; 14:349-51. [PMID: 20736127 DOI: 10.1016/j.jaapos.2010.04.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2009] [Revised: 04/10/2010] [Accepted: 04/13/2010] [Indexed: 02/03/2023]
Abstract
Leber congenital amaurosis (LCA) designates a severe congenital retinal dystrophy generally inherited in an autosomal-recessive manner and accounting for 5% of inherited retinopathies. Its main clinical features are severe visual loss, sensory nystagmus, amaurotic pupils, and unrecordable electroretinographic response. LCA has been associated with sequence variations of 14 different genes; in approximately 30% of all cases pathogenic mutations remain to be determined. We report 2 patients with a clinical phenotype of LCA associated with novel mutations of the RDH12 gene.
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Affiliation(s)
- Andrea Sodi
- Department of Oto-Neuro-Ophthalmological Surgical Sciences, Eye Clinic, Azienda Ospedaliero Universitaria Careggi, Florence, Italy
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42
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Menotti-Raymond M, Deckman KH, David V, Myrkalo J, O'Brien SJ, Narfström K. Mutation discovered in a feline model of human congenital retinal blinding disease. Invest Ophthalmol Vis Sci 2010; 51:2852-9. [PMID: 20053974 PMCID: PMC2891453 DOI: 10.1167/iovs.09-4261] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Revised: 09/29/2009] [Accepted: 12/24/2009] [Indexed: 01/12/2023] Open
Abstract
PURPOSE To elucidate the gene defect in a pedigree of cats segregating for autosomal dominant rod-cone dysplasia (Rdy), a retinopathy characterized extensively from a clinical perspective. Disease expression in Rdy cats is comparable to that in young patients with congenital blindness (Leber congenital amaurosis [LCA] or retinitis pigmentosa [RP]). METHODS A pedigree segregating for Rdy was generated and phenotyped by clinical ophthalmic examination methods including ophthalmoscopy and full-field flash electroretinography. Short tandem repeat loci tightly linked to candidate genes for autosomal dominant retinitis pigmentosa in humans were genotyped in the pedigree. RESULTS Significant linkage was established to the candidate gene CRX (LOD = 5.56, = 0) on cat chromosome E2. A single base pair deletion was identified in exon 4 (n.546delC) in affected individuals but not in unaffected littermates. This mutation generates a frame shift in the transcript, introducing a premature stop codon truncating the putative CRX peptide, which would eliminate the critical transcriptional activation region. Clinical observations corroborate previously reported clinical reports about Rdy. Results show that the cone photoreceptor system was more severely affected than the rods in the early disease process. CONCLUSIONS A putative mutation causative of the Rdy phenotype has been described as a single base pair deletion in exon 4 of the CRX gene, thus identifying the first animal model for CRX-linked disease that closely resembles the human disease. As such, it will provide valuable insights into the mechanisms underlying these diseases and their variable presentation, as well as providing a suitable model for testing therapies for these diseases.
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Affiliation(s)
- Marilyn Menotti-Raymond
- Laboratory of Genomic Diversity, National Cancer Institute-Frederick, Frederick, Maryland 21702, USA.
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43
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Cideciyan AV. Leber congenital amaurosis due to RPE65 mutations and its treatment with gene therapy. Prog Retin Eye Res 2010; 29:398-427. [PMID: 20399883 DOI: 10.1016/j.preteyeres.2010.04.002] [Citation(s) in RCA: 178] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Leber congenital amaurosis (LCA) is a rare hereditary retinal degeneration caused by mutations in more than a dozen genes. RPE65, one of these mutated genes, is highly expressed in the retinal pigment epithelium where it encodes the retinoid isomerase enzyme essential for the production of chromophore which forms the visual pigment in rod and cone photoreceptors of the retina. Congenital loss of chromophore production due to RPE65-deficiency together with progressive photoreceptor degeneration cause severe and progressive loss of vision. RPE65-associated LCA recently gained recognition outside of specialty ophthalmic circles due to early success achieved by three clinical trials of gene therapy using recombinant adeno-associated virus (AAV) vectors. The trials were built on multitude of basic, pre-clinical and clinical research defining the pathophysiology of the disease in human subjects and animal models, and demonstrating the proof-of-concept of gene (augmentation) therapy. Substantial gains in visual function of clinical trial participants provided evidence for physiologically relevant biological activity resulting from a newly introduced gene. This article reviews the current knowledge on retinal degeneration and visual dysfunction in animal models and human patients with RPE65 disease, and examines the consequences of gene therapy in terms of improvement of vision reported.
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Affiliation(s)
- Artur V Cideciyan
- Scheie Eye Institute, University of Pennsylvania, 51 North 39th St, Philadelphia, PA 19104, USA.
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44
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El Sanharawi M, Kowalczuk L, Touchard E, Omri S, de Kozak Y, Behar-Cohen F. Protein delivery for retinal diseases: from basic considerations to clinical applications. Prog Retin Eye Res 2010; 29:443-65. [PMID: 20398784 DOI: 10.1016/j.preteyeres.2010.04.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Because the eye is protected by ocular barriers but is also easily accessible, direct intravitreous injections of therapeutic proteins allow for specific and targeted treatment of retinal diseases. Low doses of proteins are required in this confined environment and a long time of residency in the vitreous is expected, making the eye the ideal organ for local proteic therapies. Monthly intravitreous injection of Ranibizumab, an anti-VEGF Fab has become the standard of care for patients presenting wet AMD. It has brought the proof of concept that administering proteins into the physiologically low proteic concentration vitreous can be performed safely. Other antibodies, Fab, peptides and growth factors have been shown to exert beneficial effects on animal models when administered within the therapeutic and safe window. To extend the use of such biomolecules in the ophthalmology practice, optimization of treatment regimens and efficacy is required. Basic knowledge remains to be increased on how different proteins/peptides penetrate into the eye and the ocular tissues, distribute in the vitreous, penetrate into the retinal layers and/or cells, are eliminated from the eye or metabolized. This should serve as a basis for designing novel drug delivery systems. The later should be non-or minimally invasive and should allow for a controlled, scalable and sustained release of the therapeutic proteins in the ocular media. This paper reviews the actual knowledge regarding protein delivery for eye diseases and describes novel non-viral gene therapy technologies particularly adapted for this purpose.
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Affiliation(s)
- M El Sanharawi
- Inserm, UMRS 872, Centre de Recherche des Cordeliers, Paris, France
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Liu M, Chen J, Xue YN, Liu WM, Zhuo RX, Huang SW. Poly(β-aminoester)s with Pendant Primary Amines for Efficient Gene Delivery. Bioconjug Chem 2009; 20:2317-23. [DOI: 10.1021/bc900317m] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Min Liu
- Key Laboratory of Biomedical Polymers of Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, P. R. China
| | - Jun Chen
- Key Laboratory of Biomedical Polymers of Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, P. R. China
| | - Ya-Nan Xue
- Key Laboratory of Biomedical Polymers of Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, P. R. China
| | - Wen-Ming Liu
- Key Laboratory of Biomedical Polymers of Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, P. R. China
| | - Ren-Xi Zhuo
- Key Laboratory of Biomedical Polymers of Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, P. R. China
| | - Shi-Wen Huang
- Key Laboratory of Biomedical Polymers of Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, P. R. China
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Veltel S, Wittinghofer A. RPGR and RP2: targets for the treatment of X-linked retinitis pigmentosa? Expert Opin Ther Targets 2009; 13:1239-51. [PMID: 19702441 DOI: 10.1517/14728220903225016] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Retinitis pigmentosa is the most important hereditary eye disease and there is currently no cure available. Although mutations were found in more than 40 genes in patients with retinitis pigmentosa, only two genes have thus far been found to be responsible for one of the most severe forms of the disease, X-linked retinitis pigmentosa. In this review, we highlight the current knowledge about the two gene products RPGR and RP2 and try to link genetic data from patients with functional data on the corresponding proteins. Based on the fact that recent gene therapeutic approaches for eye diseases are at a very promising stage, we discuss the potential of RPGR and RP2 as drug targets to treat retinitis pigmentosa.
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Affiliation(s)
- Stefan Veltel
- Max-Planck-Institut für molekulare Physiologie, Abteilung Strukturelle Biologie, Otto Hahn-Street 11, 44227 Dortmund, Germany
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Choudhary D, Jansson I, Schenkman JB. CYP1B1, a developmental gene with a potential role in glaucoma therapy. Xenobiotica 2009; 39:606-15. [PMID: 19622003 DOI: 10.1080/00498250903000198] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The association of CYP1B1 gene alterations in primary congenital glaucoma individuals has been known for about a decade. Recent evidence has shown the involvement of CYP1B1 mutations in a number of forms of glaucoma and anterior segment disorders. This suggests a wide role for CYP1B1 in ocular physiology. Histochemical studies of eyes from individuals with primary congenital glaucoma revealed abnormalities in the anterior chamber angle, the region between the cornea and the iris, containing the trabecular meshwork. The cells of the trabecular meshwork serve as a filter to allow drainage of the aqueous humour, the fluid formed by the ciliary body that fills the anterior chamber. Mutations in CYP1B1 that affect its activity have frequently been shown to influence development of the trabecular meshwork, and it is thought that CYP1B1, a monooxygenase, acts to form or degrade some endobiotic compound that is necessary for proper development of the filtering structures. The rapidly developing area of stem cell research suggests a potential therapeutic approach for glaucomas resulting from deleterious mutations in CYP1B1, that is, the transfer of stem cells, differentiated to a specific lineage, containing wild-type CYP1B1 to specific regions of the eye, where they will develop into normal cells of that region and rectify the defect.
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Affiliation(s)
- D Choudhary
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 06030, USA
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Abstract
Topical and systemic administration of drugs to the eye is highly inefficient and there is a need for controlled, sustained release, particularly for conditions that affect the posterior segment. Various nonimplantable and implantable drug delivery devices have been developed. Colloidal carriers may allow targeted drug delivery and afford protection to substances that are sensitive to degradation, particularly RNA/DNA-based treatments. Gene therapy and cell transplantation are also starting to emerge as alternatives to conventional pharmacological treatment. There is the potential to use existing ocular devices to deliver drugs. In order to exploit this opportunity, modifications to drugs and devices, along with clarification of the appropriate drug dose, must be undertaken. This review will describe some of the treatment options for ocular disease and barriers to drug delivery, discuss the design of existing drug delivery systems and highlight some of the research into combining drug delivery with existing ocular medical devices.
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Affiliation(s)
- Victoria R Kearns
- Clinical Engineering and Ophthalmology, School of Clinical Sciences, University of Liverpool, Daulby Street, Liverpool, L69 3GA, UK
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