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Busskamp V, Roska B, Sahel JA. Optogenetic Vision Restoration. Cold Spring Harb Perspect Med 2024; 14:a041660. [PMID: 37734866 PMCID: PMC11293536 DOI: 10.1101/cshperspect.a041660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/23/2023]
Abstract
Optogenetics has emerged over the past 20 years as a powerful tool to investigate the various circuits underlying numerous functions, especially in neuroscience. The ability to control by light the activity of neurons has enabled the development of therapeutic strategies aimed at restoring some level of vision in blinding retinal conditions. Promising preclinical and initial clinical data support such expectations. Numerous challenges remain to be tackled (e.g., confirmation of safety, cell and circuit specificity, patterns, intensity and mode of stimulation, rehabilitation programs) on the path toward useful vision restoration.
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Affiliation(s)
- Volker Busskamp
- Degenerative Retinal Diseases, University Hospital Bonn, 53127 Bonn, Germany
| | - Botond Roska
- Institute of Molecular and Clinical Ophthalmology Basel, 4031 Basel, Switzerland
- Department of Ophthalmology, University of Basel, 4001 Basel, Switzerland
| | - Jose-Alain Sahel
- Department of Ophthalmology, UPMC Vision Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA
- Institut Hospitalo-Universitaire FOReSIGHT, Sorbonne Universite, Inserm, Quinze-Vingts Hopital de la Vision, 75012 Paris, France
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2
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Takita Y, Sugano E, Kitabayashi K, Tabata K, Saito A, Yokoyama T, Onoguchi R, Fukuda T, Ozaki T, Bai L, Tomita H. Evaluation of Local Retinal Function in Light-Damaged Rats Using Multifocal Electroretinograms and Multifocal Visual Evoked Potentials. Int J Mol Sci 2023; 24:16433. [PMID: 38003623 PMCID: PMC10670973 DOI: 10.3390/ijms242216433] [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: 10/19/2023] [Revised: 11/09/2023] [Accepted: 11/15/2023] [Indexed: 11/26/2023] Open
Abstract
Electroretinograms (ERGs) are often used to evaluate retinal function. However, assessing local retinal function can be challenging; therefore, photopic and scotopic ERGs are used to record whole-retinal function. This study evaluated focal retinal function in rats exposed to continuous light using a multifocal ERG (mfERG) system. The rats were exposed to 1000 lux of fluorescent light for 24 h to induce photoreceptor degeneration. After light exposure, the rats were reared under cyclic light conditions (12 h: 5 lux, 12 h: dark). Photopic and multifocal ERGs and single-flash and multifocal visual evoked potentials (mfVEPs) were recorded 7 days after light exposure. Fourteen days following light exposure, paraffin-embedded sections were prepared from the eyes for histological evaluation. The ERG and VEP responses dramatically decreased after 24 h of light exposure, and retinal area-dependent decreases were observed in mfERGs and mfVEPs. Histological assessment revealed severe damage to the superior retina and less damage to the inferior retina. Considering the recorded visual angles of mfERGs and mfVEPs, the degenerated area shown on the histological examinations correlates well with the responses from multifocal recordings.
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Grants
- 21-Ⅱ4001 Terumo (Japan)
- 22H00579 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology, Japan
- 21K18278 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology, Japan
- 22K09760 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology, Japan
- 21K09713 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology, Japan
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Hiroshi Tomita
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka 020-8551, Iwate, Japan; (Y.T.); (E.S.); (K.K.); (K.T.); (A.S.); (T.Y.); (R.O.); (T.F.); (T.O.); (L.B.)
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3
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Parnami K, Bhattacharyya A. Current approaches to vision restoration using optogenetic therapy. Front Cell Neurosci 2023; 17:1236826. [PMID: 37663125 PMCID: PMC10469018 DOI: 10.3389/fncel.2023.1236826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 07/24/2023] [Indexed: 09/05/2023] Open
Abstract
Inherited progressive degeneration of photoreceptors such as retinitis pigmentosa (RP) is the most common cause of blindness leading to severe vision impairment affecting ~1 in 5,000 people worldwide. Although the function and morphology of the photoreceptors get disrupted, there is evidence that the inner retinal neurons such as bipolar cells and the retinal ganglion cells are left intact until later stages. Among several innovative therapeutic options aiming to restore vision, optogenetic therapy can bestow light sensitivity to remaining retinal neurons by ectopic expression of light-sensitive proteins. Since the advent of this technique, a diverse class of opsins (microbial and mammalian opsins), chimeric proteins, ligand-gated ion channels, and switchable opsins have been used to study their potential in vision restoration. These proteins differ in their excitation spectra, response kinetics, and signal amplification cascade. Although most of the studies have reported high fidelity of responses in the retina, only a handful of them have achieved functional vision in the visual cortex. This review is a summary of the visuocortical and behavioral responses after optogenetic treatment of the degenerated retina. This clarifies to what extent improved and meaningful vision can be obtained for therapeutic efficacy and continued clinical progress.
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Hososhima S, Ueno S, Okado S, Inoue KI, Konno M, Yamauchi Y, Inoue K, Terasaki H, Kandori H, Tsunoda SP. A light-gated cation channel with high reactivity to weak light. Sci Rep 2023; 13:7625. [PMID: 37165048 PMCID: PMC10172181 DOI: 10.1038/s41598-023-34687-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Accepted: 05/05/2023] [Indexed: 05/12/2023] Open
Abstract
The cryptophyte algae, Guillardia theta, possesses 46 genes that are homologous to microbial rhodopsins. Five of them are functionally light-gated cation channelrhodopsins (GtCCR1-5) that are phylogenetically distinct from chlorophyte channelrhodopsins (ChRs) such as ChR2 from Chlamydomonas reinhardtii. In this study, we report the ion channel properties of these five CCRs and compared them with ChR2 and other ChRs widely used in optogenetics. We revealed that light sensitivity varied among GtCCR1-5, in which GtCCR1-3 exhibited an apparent EC50 of 0.21-1.16 mW/mm2, similar to that of ChR2, whereas GtCCR4 and GtCCR5 possess two EC50s, one of which is significantly small (0.025 and 0.032 mW/mm2). GtCCR4 is able to trigger action potentials in high temporal resolution, similar to ChR2, but requires lower light power, when expressed in cortical neurons. Moreover, a high light-sensitive response was observed when GtCCR4 was introduced into blind retina ganglion cells of rd1, a mouse model of retinitis pigmentosa. Thus, GtCCR4 provides optogenetic neuronal activation with high light sensitivity and temporal precision.
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Affiliation(s)
- Shoko Hososhima
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya, Aichi, 466-8555, Japan
- OptoBioTechnology Research Center, Nagoya Institute of Technology, Showa-ku, Nagoya, Aichi, 466-8555, Japan
| | - Shinji Ueno
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi, 466-8550, Japan
- Department of Ophthalmology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Satoshi Okado
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi, 466-8550, Japan
| | - Ken-Ichi Inoue
- Primate Research Institute, Kyoto University, Inuyama, Aichi, 484-8506, Japan
| | - Masae Konno
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya, Aichi, 466-8555, Japan
- OptoBioTechnology Research Center, Nagoya Institute of Technology, Showa-ku, Nagoya, Aichi, 466-8555, Japan
- The Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8581, Japan
- PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan
| | - Yumeka Yamauchi
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya, Aichi, 466-8555, Japan
| | - Keiichi Inoue
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya, Aichi, 466-8555, Japan
- OptoBioTechnology Research Center, Nagoya Institute of Technology, Showa-ku, Nagoya, Aichi, 466-8555, Japan
- The Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8581, Japan
| | - Hiroko Terasaki
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi, 466-8550, Japan
| | - Hideki Kandori
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya, Aichi, 466-8555, Japan.
- OptoBioTechnology Research Center, Nagoya Institute of Technology, Showa-ku, Nagoya, Aichi, 466-8555, Japan.
| | - Satoshi P Tsunoda
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya, Aichi, 466-8555, Japan.
- OptoBioTechnology Research Center, Nagoya Institute of Technology, Showa-ku, Nagoya, Aichi, 466-8555, Japan.
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Hatakeyama A, Sugano E, Sayama T, Watanabe Y, Suzuki T, Tabata K, Endo Y, Sakajiri T, Fukuda T, Ozaki T, Tomita H. Properties of a Single Amino Acid Residue in the Third Transmembrane Domain Determine the Kinetics of Ambient Light-Sensitive Channelrhodopsin. Int J Mol Sci 2023; 24:ijms24055054. [PMID: 36902480 PMCID: PMC10003734 DOI: 10.3390/ijms24055054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 03/02/2023] [Accepted: 03/04/2023] [Indexed: 03/09/2023] Open
Abstract
Channelrhodopsins have been utilized in gene therapy to restore vision in patients with retinitis pigmentosa and their channel kinetics are an important factor to consider in such applications. We investigated the channel kinetics of ComV1 variants with different amino acid residues at the 172nd position. Patch clamp methods were used to record the photocurrents induced by stimuli from diodes in HEK293 cells transfected with plasmid vectors. The channel kinetics (τon and τoff) were considerably altered by the replacement of the 172nd amino acid and was dependent on the amino acid characteristics. The size of amino acids at this position correlated with τon and decay, whereas the solubility correlated with τon and τoff. Molecular dynamic simulation indicated that the ion tunnel constructed by H172, E121, and R306 widened due to H172A variant, whereas the interaction between A172 and the surrounding amino acids weakened compared with H172. The bottleneck radius of the ion gate constructed with the 172nd amino acid affected the photocurrent and channel kinetics. The 172nd amino acid in ComV1 is a key residue for determining channel kinetics as its properties alter the radius of the ion gate. Our findings can be used to improve the channel kinetics of channelrhodopsins.
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Optogenetic Therapy for Visual Restoration. Int J Mol Sci 2022; 23:ijms232315041. [PMID: 36499371 PMCID: PMC9735806 DOI: 10.3390/ijms232315041] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/29/2022] [Accepted: 11/29/2022] [Indexed: 12/02/2022] Open
Abstract
Optogenetics is a recent breakthrough in neuroscience, and one of the most promising applications is the treatment of retinal degenerative diseases. Multiple clinical trials are currently ongoing, less than a decade after the first attempt at visual restoration using optogenetics. Optogenetic therapy has great value in providing hope for visual restoration in late-stage retinal degeneration, regardless of the genotype. This alternative gene therapy consists of multiple elements including the choice of target retinal cells, optogenetic tools, and gene delivery systems. Currently, there are various options for each element, all of which have been developed as a product of technological success. In particular, the performance of optogenetic tools in terms of light and wavelength sensitivity have been improved by engineering microbial opsins and applying human opsins. To provide better post-treatment vision, the optimal choice of optogenetic tools and effective gene delivery to retinal cells is necessary. In this review, we provide an overview of the advancements in optogenetic therapy for visual restoration, focusing on available options for optogenetic tools and gene delivery methods.
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7
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Kikuchi Y, Sugano E, Yuki S, Tabata K, Endo Y, Takita Y, Onoguchi R, Ozaki T, Fukuda T, Takai Y, Kurose T, Tanaka K, Honma Y, Perez E, Stock M, Fernández JR, Tamura M, Voronkov M, Stock JB, Tomita H. SIG-1451, a Novel, Non-Steroidal Anti-Inflammatory Compound, Attenuates Light-Induced Photoreceptor Degeneration by Affecting the Inflammatory Process. Int J Mol Sci 2022; 23:ijms23158802. [PMID: 35955937 PMCID: PMC9369167 DOI: 10.3390/ijms23158802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 08/02/2022] [Accepted: 08/03/2022] [Indexed: 11/16/2022] Open
Abstract
Age-related macular degeneration is a progressive retinal disease that is associated with factors such as oxidative stress and inflammation. In this study, we evaluated the protective effects of SIG-1451, a non-steroidal anti-inflammatory compound developed for treating atopic dermatitis and known to inhibit Toll-like receptor 4, in light-induced photoreceptor degeneration. SIG-1451 was intraperitoneally injected into rats once per day before exposure to 1000 lx light for 24 h; one day later, optical coherence tomography showed a decrease in retinal thickness, and electroretinogram (ERG) amplitude was also found to have decreased 3 d after light exposure. Moreover, SIG-1451 partially protected against this decrease in retinal thickness and increase in ERG amplitude. One day after light exposure, upregulation of inflammatory response-related genes was observed, and SIG-1451 was found to inhibit this upregulation. Iba-1, a microglial marker, was suppressed in SIG-1451-injected rats. To investigate the molecular mechanism underlying these effects, we used lipopolysaccharide (LPS)-stimulated rat immortalised Müller cells. The upregulation of C-C motif chemokine 2 by LPS stimulation was significantly inhibited by SIG-1451 treatment, and Western blot analysis revealed a decrease in phosphorylated I-κB levels. These results indicate that SIG-1451 indirectly protects photoreceptor cells by attenuating light damage progression, by affecting the inflammatory responses.
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Affiliation(s)
- Yuki Kikuchi
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka 020-8551, Iwate, Japan
| | - Eriko Sugano
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka 020-8551, Iwate, Japan
| | - Shiori Yuki
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka 020-8551, Iwate, Japan
| | - Kitako Tabata
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka 020-8551, Iwate, Japan
| | - Yuka Endo
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka 020-8551, Iwate, Japan
| | - Yuya Takita
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka 020-8551, Iwate, Japan
| | - Reina Onoguchi
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka 020-8551, Iwate, Japan
| | - Taku Ozaki
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka 020-8551, Iwate, Japan
| | - Tomokazu Fukuda
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka 020-8551, Iwate, Japan
| | - Yoshihiro Takai
- Rohto Pharmaceutical Co., Ltd., 6-5-4 Kunimidai, Kizugawa 619-0216, Kyoto, Japan
| | - Takahiro Kurose
- Rohto Pharmaceutical Co., Ltd., 6-5-4 Kunimidai, Kizugawa 619-0216, Kyoto, Japan
| | - Koichi Tanaka
- Rohto Pharmaceutical Co., Ltd., 6-5-4 Kunimidai, Kizugawa 619-0216, Kyoto, Japan
| | - Yoichi Honma
- Rohto Pharmaceutical Co., Ltd., 6-5-4 Kunimidai, Kizugawa 619-0216, Kyoto, Japan
| | - Eduardo Perez
- Signum Biosciences, 4999 Pearl East Circle, Boulder, CO 80301, USA
| | - Maxwell Stock
- Signum Biosciences, 4999 Pearl East Circle, Boulder, CO 80301, USA
| | | | - Masanori Tamura
- Signum Biosciences, 4999 Pearl East Circle, Boulder, CO 80301, USA
| | - Michael Voronkov
- Signum Biosciences, 4999 Pearl East Circle, Boulder, CO 80301, USA
| | - Jeffry B. Stock
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544-1014, USA
| | - Hiroshi Tomita
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka 020-8551, Iwate, Japan
- Correspondence: ; Tel.: +81-19-621-6427
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Emiliani V, Entcheva E, Hedrich R, Hegemann P, Konrad KR, Lüscher C, Mahn M, Pan ZH, Sims RR, Vierock J, Yizhar O. Optogenetics for light control of biological systems. NATURE REVIEWS. METHODS PRIMERS 2022; 2:55. [PMID: 37933248 PMCID: PMC10627578 DOI: 10.1038/s43586-022-00136-4] [Citation(s) in RCA: 86] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/30/2022] [Indexed: 11/08/2023]
Abstract
Optogenetic techniques have been developed to allow control over the activity of selected cells within a highly heterogeneous tissue, using a combination of genetic engineering and light. Optogenetics employs natural and engineered photoreceptors, mostly of microbial origin, to be genetically introduced into the cells of interest. As a result, cells that are naturally light-insensitive can be made photosensitive and addressable by illumination and precisely controllable in time and space. The selectivity of expression and subcellular targeting in the host is enabled by applying control elements such as promoters, enhancers and specific targeting sequences to the employed photoreceptor-encoding DNA. This powerful approach allows precise characterization and manipulation of cellular functions and has motivated the development of advanced optical methods for patterned photostimulation. Optogenetics has revolutionized neuroscience during the past 15 years and is primed to have a similar impact in other fields, including cardiology, cell biology and plant sciences. In this Primer, we describe the principles of optogenetics, review the most commonly used optogenetic tools, illumination approaches and scientific applications and discuss the possibilities and limitations associated with optogenetic manipulations across a wide variety of optical techniques, cells, circuits and organisms.
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Affiliation(s)
- Valentina Emiliani
- Wavefront Engineering Microscopy Group, Photonics Department, Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Emilia Entcheva
- Department of Biomedical Engineering, George Washington University, Washington, DC, USA
| | - Rainer Hedrich
- Julius-von-Sachs Institute for Biosciences, Molecular Plant Physiology and Biophysics, University of Wuerzburg, Wuerzburg, Germany
| | - Peter Hegemann
- Institute for Biology, Experimental Biophysics, Humboldt-Universitaet zu Berlin, Berlin, Germany
| | - Kai R. Konrad
- Julius-von-Sachs Institute for Biosciences, Molecular Plant Physiology and Biophysics, University of Wuerzburg, Wuerzburg, Germany
| | - Christian Lüscher
- Department of Basic Neurosciences, Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Clinic of Neurology, Department of Clinical Neurosciences, Geneva University Hospital, Geneva, Switzerland
| | - Mathias Mahn
- Department of Neurobiology, Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Zhuo-Hua Pan
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, MI, USA
| | - Ruth R. Sims
- Wavefront Engineering Microscopy Group, Photonics Department, Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Johannes Vierock
- Institute for Biology, Experimental Biophysics, Humboldt-Universitaet zu Berlin, Berlin, Germany
- Neuroscience Research Center, Charité – Universitaetsmedizin Berlin, Berlin, Germany
| | - Ofer Yizhar
- Departments of Brain Sciences and Molecular Neuroscience, Weizmann Institute of Science, Rehovot, Israel
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Seth K, Kumawat G, Vyas P, Harish. The structure and functional mechanism of eyespot in Chlamydomonas. J Basic Microbiol 2022; 62:1169-1178. [PMID: 35778815 DOI: 10.1002/jobm.202200249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 06/11/2022] [Accepted: 06/18/2022] [Indexed: 11/05/2022]
Abstract
Light plays a crucial role in photosynthesis, photoperiodism, and photomorphogenesis. Algae have a specialized visual system to perceive the light signal known as eyespot. A typical eyespot is an orange-colored, membranous structure packed with pigmented granules. In algae, the eyespot membrane bears a specialized type of photoreceptors, which shows similarity with animal rhodopsin photoreceptors. This light-sensing receptor is responsible for the photo-mobility response known as phototaxis. In this, light acts as a signal for onset and cascade of downstream signal transduction pathway leading to a conformational change in photoreceptor. This induces the continuous influx of calcium ions through the opening of calcium ion channels leading to membrane depolarization, and beating of flagella which is responsible for phototaxis. Mutational studies have assisted the discovery of eyespot genes, which are involved in eyespot development, assembly, size control, and functioning in Chlamydomonas. These genes belong to photoreceptors (cop1-12, acry, pcry, cry-dash1, cry-dash2, phot, uvr8), eyeless mutants (eye2, eye3), miniature-eyespot mutants (min1, min2), multiple eyespot mutants (mlt1, mlt2). This review discusses the structural biology of eyespots with special reference to Chlamydomonas, molecular insights, related genes, and proteins responsible for its proper functioning.
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Affiliation(s)
- Kunal Seth
- Department of Botany, Govt. Science College, Pardi Valsad, Gujarat, India
| | - Geetanjali Kumawat
- Plant Biotechnology Laboratory, Department of Botany, Mohanlal Sukhadia University, Udaipur, Rajasthan, India
| | - Pallavi Vyas
- Plant Biotechnology Laboratory, Department of Botany, Mohanlal Sukhadia University, Udaipur, Rajasthan, India
| | - Harish
- Plant Biotechnology Laboratory, Department of Botany, Mohanlal Sukhadia University, Udaipur, Rajasthan, India
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10
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Lindner M, Gilhooley MJ, Hughes S, Hankins MW. Optogenetics for visual restoration: From proof of principle to translational challenges. Prog Retin Eye Res 2022; 91:101089. [PMID: 35691861 DOI: 10.1016/j.preteyeres.2022.101089] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 05/17/2022] [Accepted: 05/19/2022] [Indexed: 01/04/2023]
Abstract
Degenerative retinal disorders are a diverse family of diseases commonly leading to irreversible photoreceptor death, while leaving the inner retina relatively intact. Over recent years, innovative gene replacement therapies aiming to halt the progression of certain inherited retinal disorders have made their way into clinics. By rendering surviving retinal neurons light sensitive optogenetic gene therapy now offers a feasible treatment option that can restore lost vision, even in late disease stages and widely independent of the underlying cause of degeneration. Since proof-of-concept almost fifteen years ago, this field has rapidly evolved and a detailed first report on a treated patient has recently been published. In this article, we provide a review of optogenetic approaches for vision restoration. We discuss the currently available optogenetic tools and their relative advantages and disadvantages. Possible cellular targets will be discussed and we will address the question how retinal remodelling may affect the choice of the target and to what extent it may limit the outcomes of optogenetic vision restoration. Finally, we will analyse the evidence for and against optogenetic tool mediated toxicity and will discuss the challenges associated with clinical translation of this promising therapeutic concept.
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Affiliation(s)
- Moritz Lindner
- The Nuffield Laboratory of Ophthalmology, Jules Thorn SCNi, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX1 3QU, United Kingdom; Institute of Physiology and Pathophysiology, Department of Neurophysiology, Philipps University, 35037, Marburg, Germany
| | - Michael J Gilhooley
- The Nuffield Laboratory of Ophthalmology, Jules Thorn SCNi, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX1 3QU, United Kingdom; The Institute of Ophthalmology, University College London, EC1V 9EL, United Kingdom; Moorfields Eye Hospital, London, EC1V 2PD, United Kingdom
| | - Steven Hughes
- The Nuffield Laboratory of Ophthalmology, Jules Thorn SCNi, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX1 3QU, United Kingdom
| | - Mark W Hankins
- The Nuffield Laboratory of Ophthalmology, Jules Thorn SCNi, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX1 3QU, United Kingdom.
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11
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Menon A, Vijayavenkataraman S. Novel vision restoration techniques: 3D bioprinting, gene and stem cell therapy, optogenetics, and the bionic eye. Artif Organs 2022; 46:1463-1474. [PMID: 35373344 DOI: 10.1111/aor.14241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 03/18/2022] [Accepted: 03/18/2022] [Indexed: 11/29/2022]
Abstract
BACKGROUND Vision restoration has been one of the most sought-after goals of ophthalmology because of its inception. Despite these problems being tackled from numerous different perspectives, a concrete solution has not yet been achieved. An optimal solution will have significant implications on the patient's quality of life, socioeconomic status, and mental health. METHODS This article will explore new and innovative approaches with one common aim-to restore functional vision for the visually impaired. These novel techniques include 3D bioprinting, stem cell therapy, gene therapy, implantable devices, and optogenetics. RESULTS While the techniques mentioned above show significant promise, they are currently in various stages of development ranging from clinical trials to commercial availability. Restoration of minimal vision in specific cases has already been achieved by the different methods but optimization of different parameters like biocompatibility, spatiotemporal resolution, and minimizing the costs are essential for widespread use. CONCLUSION The developments over the past decade have resulted in multiple milestones in each of the techniques with many solutions getting approved by the FDA. This article will compare these novel techniques and highlight the major advantages and drawbacks of each of them.
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Affiliation(s)
- Abhay Menon
- The Vijay Lab, Division of Engineering, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Sanjairaj Vijayavenkataraman
- The Vijay Lab, Division of Engineering, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates.,Department of Mechanical and Aerospace Engineering, Tandon School of Engineering, New York University, Brooklyn, New York, USA
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12
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Martinez Velazquez LA, Ballios BG. The Next Generation of Molecular and Cellular Therapeutics for Inherited Retinal Disease. Int J Mol Sci 2021; 22:ijms222111542. [PMID: 34768969 PMCID: PMC8583900 DOI: 10.3390/ijms222111542] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 10/13/2021] [Accepted: 10/14/2021] [Indexed: 12/26/2022] Open
Abstract
Inherited retinal degenerations (IRDs) are a diverse group of conditions that are often characterized by the loss of photoreceptors and blindness. Recent innovations in molecular biology and genomics have allowed us to identify the causative defects behind these dystrophies and to design therapeutics that target specific mechanisms of retinal disease. Recently, the FDA approved the first in vivo gene therapy for one of these hereditary blinding conditions. Current clinical trials are exploring new therapies that could provide treatment for a growing number of retinal dystrophies. While the field has had early success with gene augmentation strategies for treating retinal disease based on loss-of-function mutations, many novel approaches hold the promise of offering therapies that span the full spectrum of causative mutations and mechanisms. Here, we provide a comprehensive review of the approaches currently in development including a discussion of retinal neuroprotection, gene therapies (gene augmentation, gene editing, RNA modification, optogenetics), and regenerative stem or precursor cell-based therapies. Our review focuses on technologies that are being developed for clinical translation or are in active clinical trials and discusses the advantages and limitations for each approach.
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Affiliation(s)
| | - Brian G. Ballios
- Department of Ophthalmology and Vision Sciences, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5T 3A9, Canada
- Correspondence:
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13
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Development of an optogenetic gene sensitive to daylight and its implications in vision restoration. NPJ Regen Med 2021; 6:64. [PMID: 34650094 PMCID: PMC8516861 DOI: 10.1038/s41536-021-00177-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 09/29/2021] [Indexed: 11/14/2022] Open
Abstract
Optogenetic gene-mediated therapy for restoring vision is thought to be a useful treatment for blind patients. However, light sensitivity achieved using this gene therapy is inferior to that of daylight vision. To increase light sensitivity, we designed three mutants using a bioinformatics approach. Nucleotide sequences encoding two sites in the extracellular loops (ex1, ex3) of mVChR1 close to simulated ion-conducting pathways were replaced by homologous amino acid-encoding sequences of ChR1 or ChR2. The light sensitivity of ex3mV1 was higher than that of mVChR1 at 405–617 nm. Visual responses were restored in Royal College of Surgeons rats with genetically degenerating photoreceptor cells transfected with ex3mV1Co, wherein transmembrane of sixth (TM6) in ex3mV1 was additionally replaced with the corresponding domain of CoChR; these rats responded to light in the order of μW/mm2. Thus, ex3mV1Co might be useful for the restoration of advanced visual function.
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14
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Van Gelder RN. Gene Therapy Approaches to Slow or Reverse Blindness From Inherited Retinal Degeneration: Growth Factors and Optogenetics. Int Ophthalmol Clin 2021; 61:209-228. [PMID: 34584058 PMCID: PMC8486303 DOI: 10.1097/iio.0000000000000386] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
To date, clinical gene therapy efforts for inherited retinal degeneration (IRD) have focused largely on gene replacement. The large number of genes and alleles causing IRD, however, makes this approach practical only for the most common causes. Additionally, gene replacement therapy cannot reverse existing retinal degeneration. Viral-mediated gene therapy can be used for two other approaches to slow or reverse IRD. First, by driving intraocular expression of growth factors or neuroprotective proteins, retinal degeneration can be slowed. Second, by expressing light-sensitive proteins (either microbial channelopsins or mammalian G-protein coupled opsins) in preserved inner retinal neurons, light sensitivity can be restored to the blind retina. Both approaches have advanced substantially in the past decade, and both are nearing clinical tests. This review surveys recent progress in these approaches.
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15
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Keshmiri Neghab H, Soheilifar MH, Grusch M, Ortega MM, Esmaeeli Djavid G, Saboury AA, Goliaei B. The state of the art of biomedical applications of optogenetics. Lasers Surg Med 2021; 54:202-216. [PMID: 34363230 DOI: 10.1002/lsm.23463] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 07/08/2021] [Accepted: 07/23/2021] [Indexed: 12/31/2022]
Abstract
BACKGROUND AND OBJECTIVE Optogenetics has opened new insights into biomedical research with the ability to manipulate and control cellular activity using light in combination with genetically engineered photosensitive proteins. By stimulating with light, this method provides high spatiotemporal and high specificity resolution, which is in contrast to conventional pharmacological or electrical stimulation. Optogenetics was initially introduced to control neural activities but was gradually extended to other biomedical fields. STUDY DESIGN In this paper, firstly, we summarize the current optogenetic tools stimulated by different light sources, including lasers, light-emitting diodes, and laser diodes. Second, we outline the variety of biomedical applications of optogenetics not only for neuronal circuits but also for various kinds of cells and tissues from cardiomyocytes to ganglion cells. Furthermore, we highlight the potential of this technique for treating neurological disorders, cardiac arrhythmia, visual impairment, hearing loss, and urinary bladder diseases as well as clarify the mechanisms underlying cancer progression and control of stem cell differentiation. CONCLUSION We sought to summarize the various types of promising applications of optogenetics to treat a broad spectrum of disorders. It is conceivable to expect that optogenetics profits a growing number of patients suffering from a range of different diseases in the near future.
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Affiliation(s)
- Hoda Keshmiri Neghab
- Department of Photo Healing and Regeneration, Medical Laser Research Center, Yara Institute, ACECR, Tehran, Iran
| | | | - Michael Grusch
- Department of Medicine I, Institute of Cancer Research, Medical University of Vienna, Vienna, Austria
| | - Manoela Marques Ortega
- Laboratory of Cell and Molecular Tumor Biology and Bioactive Compounds, São Francisco University, Bragança Paulista, São Paulo, Brazil
| | - Gholamreza Esmaeeli Djavid
- Department of Photo Healing and Regeneration, Medical Laser Research Center, Yara Institute, ACECR, Tehran, Iran
| | - Ali Akbar Saboury
- Department of Biophysics, Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
| | - Bahram Goliaei
- Department of Biophysics, Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
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16
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Bansal H, Gupta N, Roy S. Theoretical analysis of optogenetic spiking with ChRmine, bReaChES and CsChrimson-expressing neurons for retinal prostheses. J Neural Eng 2021; 18. [PMID: 34229315 DOI: 10.1088/1741-2552/ac1175] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 07/06/2021] [Indexed: 01/10/2023]
Abstract
Objective.Optogenetics has emerged as a promising technique for neural prosthetics, especially retinal prostheses, with unprecedented spatiotemporal resolution. Newly discovered opsins with high light sensitivity and fast temporal kinetics can provide sufficient temporal resolution at safe light powers and overcome the limitations of presently used opsins. It is also important to formulate accurate mathematical models for optogenetic retinal prostheses, which can facilitate optimization of photostimulation factors to improve the performance.Approach.A detailed theoretical analysis of optogenetic excitation of model retinal ganglion neurons (RGNs) and hippocampal neurons expressed with already tested opsins for retinal prostheses, namely, ChR2, ReaChR and ChrimsonR, and also with recently discovered potent opsins CsChrimson, bReaChES and ChRmine, was carried out.Main results.Under continuous illumination, ChRmine-expressing RGNs begin to respond at very low irradiances ∼10-4mW mm-2, and evoke firing upto ∼280 Hz, highest among other opsin-expressing RGNs, at 10-2mW mm-2. Under pulsed illumination at randomized photon fluxes, ChRmine-expressing RGNs respond to changes in pulse to pulse irradiances upto four logs, although very bright pulses >1014photons mm-2s-1block firing in these neurons. The minimum irradiance threshold for ChRmine-expressing RGNs is lower by two orders of magnitude, whereas, the first spike latency in ChRmine-expressing RGNs is shorter by an order of magnitude, alongwith stable latency of subsequest spikes compared to others. Further, a good set of photostimulation parameters were determined to achieve high-frequency control with single spike resolution at minimal power. Although ChrimsonR enables spiking upto 100 Hz in RGNs, it requires very high irradiances. ChRmine provides control at light powers that are two orders of magnitude smaller than that required with experimentally studied opsins, while maintaining single spike temporal resolution upto 40 Hz.Significance.The present study highlights the importance of ChRmine as a potential opsin for optogenetic retinal prostheses.
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Affiliation(s)
- Himanshu Bansal
- Department of Physics and Computer Science, Dayalbagh Educational Institute, Agra 282005, India
| | - Neha Gupta
- Department of Physics and Computer Science, Dayalbagh Educational Institute, Agra 282005, India
| | - Sukhdev Roy
- Department of Physics and Computer Science, Dayalbagh Educational Institute, Agra 282005, India
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17
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Phototoxicities Caused by Continuous Light Exposure Were Not Induced in Retinal Ganglion Cells Transduced by an Optogenetic Gene. Int J Mol Sci 2021; 22:ijms22136732. [PMID: 34201658 PMCID: PMC8269149 DOI: 10.3390/ijms22136732] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 06/16/2021] [Accepted: 06/22/2021] [Indexed: 11/16/2022] Open
Abstract
The death of photoreceptor cells is induced by continuous light exposure. However, it is unclear whether light damage was induced in retinal ganglion cells with photosensitivity by transduction of optogenetic genes. In this study, we evaluated the phototoxicities of continuous light exposure on retinal ganglion cells after transduction of the optogenetic gene mVChR1 using an adeno-associated virus vector. Rats were exposed to continuous light for a week, and visually evoked potentials (VEPs) were recorded. The intensities of continuous light (500, 1000, 3000, and 5000 lx) increased substantially after VEP recordings. After the final recording of VEPs, retinal ganglion cells (RGCs) were retrogradely labeled with a fluorescein tracer, FluoroGold, and the number of retinal ganglion cells was counted under a fluorescent microscope. There was no significant reduction in the amplitudes of VEPs and the number of RGCs after exposure to any light intensity. These results indicated that RGCs were photosensitive after the transduction of optogenetic genes and did not induce any phototoxicity by continuous light exposure.
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18
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Botto C, Rucli M, Tekinsoy MD, Pulman J, Sahel JA, Dalkara D. Early and late stage gene therapy interventions for inherited retinal degenerations. Prog Retin Eye Res 2021; 86:100975. [PMID: 34058340 DOI: 10.1016/j.preteyeres.2021.100975] [Citation(s) in RCA: 74] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 05/18/2021] [Accepted: 05/21/2021] [Indexed: 12/12/2022]
Abstract
Inherited and age-related retinal degeneration is the hallmark of a large group of heterogeneous diseases and is the main cause of untreatable blindness today. Genetic factors play a major pathogenic role in retinal degenerations for both monogenic diseases (such as retinitis pigmentosa) and complex diseases with established genetic risk factors (such as age-related macular degeneration). Progress in genotyping techniques and back of the eye imaging are completing our understanding of these diseases and their manifestations in patient populations suffering from retinal degenerations. It is clear that whatever the genetic cause, the majority of vision loss in retinal diseases results from the loss of photoreceptor function. The timing and circumstances surrounding the loss of photoreceptor function determine the adequate therapeutic approach to use for each patient. Among such approaches, gene therapy is rapidly becoming a therapeutic reality applicable in the clinic. This massive move from laboratory work towards clinical application has been propelled by the advances in our understanding of disease genetics and mechanisms, gene delivery vectors, gene editing systems, and compensatory strategies for loss of photoreceptor function. Here, we provide an overview of existing modalities of retinal gene therapy and their relevance based on the needs of patient populations suffering from inherited retinal degenerations.
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Affiliation(s)
- Catherine Botto
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France
| | - Marco Rucli
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France
| | - Müge Defne Tekinsoy
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France
| | - Juliette Pulman
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France
| | - José-Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France; Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, United States; CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, F-75012, Paris, France; Fondation Ophtalmologique Rothschild, F-75019, Paris, France
| | - Deniz Dalkara
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France.
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19
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Optogenetics-Mediated Gene Therapy for Retinal Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1293:535-543. [PMID: 33398840 DOI: 10.1007/978-981-15-8763-4_37] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The visual system consists of various types of neurons and a single-nucleotide mutation can sometimes lead to blindness. The phototransduction pathway in the retina starts from the first-order neurons, the photoreceptor cells, and transmits the signals to second-order neurons. Finally, the output signal from third-order neurons, the ganglion cells, is carried to the brain. The photoreceptor cells are the only neurons in the retina that can respond to a light signal; they are hyperpolarised when they receive light, and the ganglion cells carry the signals to the brain following the depolarization. Recently, various types of channelrhodopsins have been found and developed. It is expected that the gene therapies using the cation channel as well as anion channelrhodopsin genes would be effective against diseases that cause severe destruction of visual function, such as the retinitis pigmentosa and age-related macular degeneration. In this review, we mainly describe mVChR1-mediated gene therapy for retinitis pigmentosa and the future application of optogenetic genes in retinal diseases.
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20
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Dhakal KR, Walters S, McGregor JE, Schwarz C, Strazzeri JM, Aboualizadeh E, Bateman B, Huxlin KR, Hunter JJ, Williams DR, Merigan WH. Localized Photoreceptor Ablation Using Femtosecond Pulses Focused With Adaptive Optics. Transl Vis Sci Technol 2020; 9:16. [PMID: 32832223 PMCID: PMC7414617 DOI: 10.1167/tvst.9.7.16] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 04/09/2020] [Indexed: 02/03/2023] Open
Abstract
Purpose The development of new approaches to human vision restoration could be greatly accelerated with the use of nonhuman primate models; however, there is a paucity of primate models of outer retina degeneration with good spatial localization. To limit ablation to the photoreceptors, we developed a new approach that uses a near-infrared ultrafast laser, focused using adaptive optics, to concentrate light in a small focal volume within the retina. Methods In the eyes of eight anesthetized macaques, 187 locations were exposed to laser powers from 50 to 210 mW. Laser exposure locations were monitored for up to 18 months using fluorescein angiography (FA), optical coherence tomography (OCT), scanning laser ophthalmoscopy (SLO), adaptive optics scanning laser ophthalmoscope (AOSLO) reflectance imaging, two-photon excited fluorescence (TPEF) ophthalmoscopy, histology, and calcium responses of retinal ganglion cells. Results This method produced localized photoreceptor loss with minimal axial spread of damage to other retinal layers, verified by in-vivo structural imaging and histologic examination, although in some cases evidence of altered autofluorescence was found in the adjacent retinal pigment epithelium (RPE). Functional assessment using blood flow imaging of the retinal plexus and calcium imaging of the response of ganglion cells above the photoreceptor loss shows that inner retinal circuitry was preserved. Conclusions Although different from a genetic model of retinal degeneration, this model of localized photoreceptor loss may provide a useful testbed for vision restoration studies in nonhuman primates. Translational Relevance With this model, a variety of vision restoration methods can be tested in the non-human primate.
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Affiliation(s)
- Kamal R Dhakal
- Center for Visual Science, University of Rochester, Rochester, NY, USA
| | - Sarah Walters
- Center for Visual Science, University of Rochester, Rochester, NY, USA.,The Institute of Optics, University of Rochester, Rochester, NY, USA
| | | | - Christina Schwarz
- Center for Visual Science, University of Rochester, Rochester, NY, USA.,Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | | | | | - Brittany Bateman
- Flaum Eye Institute, University of Rochester, Rochester, NY, USA
| | - Krystel R Huxlin
- Center for Visual Science, University of Rochester, Rochester, NY, USA.,The Institute of Optics, University of Rochester, Rochester, NY, USA.,Flaum Eye Institute, University of Rochester, Rochester, NY, USA
| | - Jennifer J Hunter
- Center for Visual Science, University of Rochester, Rochester, NY, USA.,The Institute of Optics, University of Rochester, Rochester, NY, USA.,Flaum Eye Institute, University of Rochester, Rochester, NY, USA
| | - David R Williams
- Center for Visual Science, University of Rochester, Rochester, NY, USA.,The Institute of Optics, University of Rochester, Rochester, NY, USA
| | - William H Merigan
- Center for Visual Science, University of Rochester, Rochester, NY, USA.,Flaum Eye Institute, University of Rochester, Rochester, NY, USA
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21
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Simon CJ, Sahel JA, Duebel J, Herlitze S, Dalkara D. Opsins for vision restoration. Biochem Biophys Res Commun 2020; 527:325-330. [DOI: 10.1016/j.bbrc.2019.12.117] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 12/20/2019] [Indexed: 12/17/2022]
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22
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Comparison of AAV-Mediated Optogenetic Vision Restoration between Retinal Ganglion Cell Expression and ON Bipolar Cell Targeting. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2020; 18:15-23. [PMID: 32548211 PMCID: PMC7287188 DOI: 10.1016/j.omtm.2020.05.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 05/19/2020] [Indexed: 01/06/2023]
Abstract
The loss of photoreceptors in individuals with retinal degenerative diseases leads to partial or complete blindness. Optogenetic therapy is a promising approach for restoring vision to the blind. Multiple strategies have been employed by targeting genetically encoded light sensors, particularly channelrhodopsins, to surviving retinal neurons in animal models. In particular, the strategy of targeting retinal bipolar cells has commonly been expected to result in better vision than ubiquitous expression in retinal ganglion cells. However, a direct comparison of the channelrhodopsin-restored vision between these two strategies has not been performed. Here, we compared the restored visual functions achieved by adeno-associated virus (AAV)-mediated expression of a channelrhodopsin in ON-type bipolar cells and retinal ganglion cells driven by an improved mGluR6 promoter and a CAG promoter, respectively, in a blind mouse model by performing electrophysiological recordings and behavioral assessments. Unexpectedly, the efficacy of the restored vision based on light sensitivity and visual acuity was much higher following ubiquitous retinal ganglion cell expression than that of the strategy targeting ON-type bipolar cells. Our study suggests that, at least based on currently available gene delivery techniques, the expression of genetically encoded light sensors in retinal ganglion cells is likely a practical and advantageous strategy for optogenetic vision restoration.
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23
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Kamar S, Howlett MHC, Klooster J, de Graaff W, Csikós T, Rabelink MJWE, Hoeben RC, Kamermans M. Degenerated Cones in Cultured Human Retinas Can Successfully Be Optogenetically Reactivated. Int J Mol Sci 2020; 21:ijms21020522. [PMID: 31947650 PMCID: PMC7014344 DOI: 10.3390/ijms21020522] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/11/2020] [Accepted: 01/13/2020] [Indexed: 12/14/2022] Open
Abstract
Biblical references aside, restoring vision to the blind has proven to be a major technical challenge. In recent years, considerable advances have been made towards this end, especially when retinal degeneration underlies the vision loss such as occurs with retinitis pigmentosa. Under these conditions, optogenetic therapies are a particularly promising line of inquiry where remaining retinal cells are made into "artificial photoreceptors". However, this strategy is not without its challenges and a model system using human retinal explants would aid its continued development and refinement. Here, we cultured post-mortem human retinas and show that explants remain viable for around 7 days. Within this period, the cones lose their outer segments and thus their light sensitivity but remain electrophysiologically intact, displaying all the major ionic conductances one would expect for a vertebrate cone. We optogenetically restored light responses to these quiescent cones using a lentivirus vector constructed to express enhanced halorhodopsin under the control of the human arrestin promotor. In these 'reactivated' retinas, we show a light-induced horizontal cell to cone feedback signal in cones, indicating that transduced cones were able to transmit their light response across the synapse to horizontal cells, which generated a large enough response to send a signal back to the cones. Furthermore, we show ganglion cell light responses, suggesting the cultured explant's condition is still good enough to support transmission of the transduced cone signal over the intermediate retinal layers to the final retinal output level. Together, these results show that cultured human retinas are an appropriate model system to test optogenetic vision restoration approaches and that cones which have lost their outer segment, a condition occurring during the early stages of retinitis pigmentosa, are appropriate targets for optogenetic vision restoration therapies.
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Affiliation(s)
- Sizar Kamar
- Netherlands Institute for Neuroscience, 1105 BA Amsterdam-Zuidoost, The Netherlands; (S.K.); (M.H.C.H.); (J.K.); (W.d.G.); (T.C.)
- Department of Ophthalmology, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden, The Netherlands
| | - Marcus H. C. Howlett
- Netherlands Institute for Neuroscience, 1105 BA Amsterdam-Zuidoost, The Netherlands; (S.K.); (M.H.C.H.); (J.K.); (W.d.G.); (T.C.)
| | - Jan Klooster
- Netherlands Institute for Neuroscience, 1105 BA Amsterdam-Zuidoost, The Netherlands; (S.K.); (M.H.C.H.); (J.K.); (W.d.G.); (T.C.)
| | - Wim de Graaff
- Netherlands Institute for Neuroscience, 1105 BA Amsterdam-Zuidoost, The Netherlands; (S.K.); (M.H.C.H.); (J.K.); (W.d.G.); (T.C.)
| | - Tamás Csikós
- Netherlands Institute for Neuroscience, 1105 BA Amsterdam-Zuidoost, The Netherlands; (S.K.); (M.H.C.H.); (J.K.); (W.d.G.); (T.C.)
| | - Martijn J. W. E. Rabelink
- Department of Cell and Chemical Biology, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden, The Netherlands; (M.J.W.E.R.); (R.C.H.)
| | - Rob C. Hoeben
- Department of Cell and Chemical Biology, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden, The Netherlands; (M.J.W.E.R.); (R.C.H.)
| | - Maarten Kamermans
- Netherlands Institute for Neuroscience, 1105 BA Amsterdam-Zuidoost, The Netherlands; (S.K.); (M.H.C.H.); (J.K.); (W.d.G.); (T.C.)
- Department of Biomedical Engineering & Physics, Amsterdam University Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
- Correspondence:
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24
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Kurose T, Sugano E, Sugai A, Shiraiwa R, Kato M, Mitsuguchi Y, Takai Y, Tabata K, Honma Y, Tomita H. Neuroprotective effect of a dietary supplement against glutamate-induced excitotoxicity in retina. Int J Ophthalmol 2019; 12:1231-1237. [PMID: 31456911 DOI: 10.18240/ijo.2019.08.01] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 06/04/2019] [Indexed: 01/17/2023] Open
Abstract
AIM To evaluate the neuroprotective effect of a dietary supplement (ClearVision EX®; CV) against glutamate-induced excitotoxicity in retina. METHODS We evaluated the protective effects CV on glutamate-induced cell toxicity of an immortalized mouse hippocampal cell line (HT-22) in vitro and N-methyl-D-aspartate (NMDA) induced retinal injury in vivo. Once-daily oral administration of CV or vehicle (5% Arabic gum) was started the day before the NMDA injection and continued until the end of the study. Electroretinograms (ERGs) were recorded to evaluate the retinal function at 2d after NMDA injection. Furthermore, a histological evaluation, Western blot analysis, and immunohistochemistry were performed for assessing the signal transduction pathway. RESULTS HT-22 cell death was induced by the addition of glutamate and co-incubation with CV protected against it. Oral administration of CV inhibited the decrease in scotopic threshold response amplitudes induced by the intravitreal injection of NMDA and those of the thickness of the inner retinal layer in the histological evaluation. The increased phosphorylated levels of extracellular signal-regulated kinase (ERK) but not cAMP response element binding protein (CREB) or Akt were observed 1h after NMDA injection in both the vehicle- and CV-treated rats; however, pERK activation was no more upregulated at 3h after NMDA injection. pERK upregulation was observed in Müller cells. CONCLUSION CV shows a protective effect against both glutamate-induced HT-22 cell death and NMDA-induced retinal damage. pERK upregulation in the Müller cells plays a key role in the protective effect of CV against glutamate-induced retinal toxicity.
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Affiliation(s)
- Takahiro Kurose
- Rohto Pharmaceutical Co., Ltd., 6-5-4 Kunimidai, Kizugawa, Kyoto 619-0216, Japan
| | - Eriko Sugano
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan
| | - Akihisa Sugai
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan
| | - Raki Shiraiwa
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan
| | - Mariyo Kato
- Rohto Pharmaceutical Co., Ltd., 6-5-4 Kunimidai, Kizugawa, Kyoto 619-0216, Japan
| | - Yoko Mitsuguchi
- Rohto Pharmaceutical Co., Ltd., 6-5-4 Kunimidai, Kizugawa, Kyoto 619-0216, Japan
| | - Yoshihiro Takai
- Rohto Pharmaceutical Co., Ltd., 6-5-4 Kunimidai, Kizugawa, Kyoto 619-0216, Japan
| | - Kitako Tabata
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan
| | - Yoichi Honma
- Rohto Pharmaceutical Co., Ltd., 6-5-4 Kunimidai, Kizugawa, Kyoto 619-0216, Japan
| | - Hiroshi Tomita
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan.,Clinical Research, Innovation and Education Center, Tohoku University Hospital, 1-1 Seiryo, Aoba, Sendai, Miyagi 980-8574, Japan
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25
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Maeda A, Mandai M, Takahashi M. Gene and Induced Pluripotent Stem Cell Therapy for Retinal Diseases. Annu Rev Genomics Hum Genet 2019; 20:201-216. [PMID: 31018110 DOI: 10.1146/annurev-genom-083118-015043] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Given the importance of visual information to many daily activities, retinal degenerative diseases-which include both inherited conditions (such as retinitis pigmentosa) and acquired conditions (such as age-related macular degeneration)-can have a dramatic impact on human lives. The therapeutic options for these diseases remain limited. Since the discovery of the first causal gene for retinitis pigmentosa almost three decades ago, more than 250 genes have been identified, and gene therapies have been rapidly developed. Simultaneously, stem cell technologies such as induced pluripotent stem cell-based transplantation have advanced and have been applied to the treatment of retinal degenerative diseases. Here, we review recent progress in these expanding fields and discuss the potential for precision medicine in ophthalmic care.
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Affiliation(s)
- Akiko Maeda
- Laboratory for Retinal Regeneration, Center for Biosystems Dynamics Research, RIKEN, Kobe, Hyogo 650-0047, Japan;
| | - Michiko Mandai
- Laboratory for Retinal Regeneration, Center for Biosystems Dynamics Research, RIKEN, Kobe, Hyogo 650-0047, Japan;
| | - Masayo Takahashi
- Laboratory for Retinal Regeneration, Center for Biosystems Dynamics Research, RIKEN, Kobe, Hyogo 650-0047, Japan; .,Kobe City Eye Center Hospital, Kobe, Hyogo 650-0047, Japan
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Ganjawala TH, Lu Q, Fenner MD, Abrams GW, Pan ZH. Improved CoChR Variants Restore Visual Acuity and Contrast Sensitivity in a Mouse Model of Blindness under Ambient Light Conditions. Mol Ther 2019; 27:1195-1205. [PMID: 31010741 DOI: 10.1016/j.ymthe.2019.04.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 04/03/2019] [Accepted: 04/03/2019] [Indexed: 11/15/2022] Open
Abstract
Severe photoreceptor cell death in retinal degenerative diseases leads to partial or complete blindness. Optogenetics is a promising strategy to treat blindness. The feasibility of this strategy has been demonstrated through the ectopic expression of microbial channelrhodopsins (ChRs) and other genetically encoded light sensors in surviving retinal neurons in animal models. A major drawback for ChR-based visual restoration is low light sensitivity. Here, we report the development of highly operational light-sensitive ChRs by optimizing the kinetics of a recently reported ChR variant, Chloromonas oogama (CoChR). In particular, we identified two CoChR mutants, CoChR-L112C and CoChR-H94E/L112C/K264T, with markedly enhanced light sensitivity. The improved light sensitivity of the CoChR mutants was confirmed by ex vivo electrophysiological recordings in the retina. Furthermore, the CoChR mutants restored the vision of a blind mouse model under ambient light conditions with remarkably good contrast sensitivity and visual acuity, as evidenced by the results of behavioral assays. The ability to restore functional vision under normal light conditions with the improved CoChR variants removed a major obstacle for ChR-based optogenetic vision restoration.
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Affiliation(s)
- Tushar H Ganjawala
- Department of Ophthalmology, Visual and Anatomical Sciences, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA
| | - Qi Lu
- Department of Ophthalmology, Visual and Anatomical Sciences, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA
| | - Mitchell D Fenner
- Department of Ophthalmology, Visual and Anatomical Sciences, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA
| | - Gary W Abrams
- Department of Ophthalmology, Visual and Anatomical Sciences, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA
| | - Zhuo-Hua Pan
- Department of Ophthalmology, Visual and Anatomical Sciences, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA.
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27
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Garita-Hernandez M, Guibbal L, Toualbi L, Routet F, Chaffiol A, Winckler C, Harinquet M, Robert C, Fouquet S, Bellow S, Sahel JA, Goureau O, Duebel J, Dalkara D. Optogenetic Light Sensors in Human Retinal Organoids. Front Neurosci 2018; 12:789. [PMID: 30450028 PMCID: PMC6224345 DOI: 10.3389/fnins.2018.00789] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 10/12/2018] [Indexed: 01/26/2023] Open
Abstract
Optogenetic technologies paved the way to dissect complex neural circuits and monitor neural activity using light in animals. In retinal disease, optogenetics has been used as a therapeutic modality to reanimate the retina after the loss of photoreceptor outer segments. However, it is not clear today which ones of the great diversity of microbial opsins are best suited for therapeutic applications in human retinas as cell lines, primary cell cultures and animal models do not predict expression patterns of microbial opsins in human retinal cells. Therefore, we sought to generate retinal organoids derived from human induced pluripotent stem cells (hiPSCs) as a screening tool to explore the membrane trafficking efficacy of some recently described microbial opsins. We tested both depolarizing and hyperpolarizing microbial opsins including CatCh, ChrimsonR, ReaChR, eNpHR 3.0, and Jaws. The membrane localization of eNpHR 3.0, ReaChR, and Jaws was the highest, likely due to their additional endoplasmic reticulum (ER) release and membrane trafficking signals. In the case of opsins that were not engineered to improve trafficking efficiency in mammalian cells such as CatCh and ChrimsonR, membrane localization was less efficient. Protein accumulation in organelles such as ER and Golgi was observed at high doses with CatCh and ER retention lead to an unfolded protein response. Also, cytoplasmic localization was observed at high doses of ChrimsonR. Our results collectively suggest that retinal organoids derived from hiPSCs can be used to predict the subcellular fate of optogenetic proteins in a human retinal context. Such organoids are also versatile tools to validate other gene therapy products and drug molecules.
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Affiliation(s)
| | - Laure Guibbal
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Lyes Toualbi
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Fiona Routet
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Antoine Chaffiol
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Celine Winckler
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Marylin Harinquet
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Camille Robert
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Stephane Fouquet
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | | | - José-Alain Sahel
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
- CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, Paris, France
- Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Olivier Goureau
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Jens Duebel
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Deniz Dalkara
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
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Baker CK, Flannery JG. Innovative Optogenetic Strategies for Vision Restoration. Front Cell Neurosci 2018; 12:316. [PMID: 30297985 PMCID: PMC6160748 DOI: 10.3389/fncel.2018.00316] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 08/30/2018] [Indexed: 12/27/2022] Open
Abstract
The advent of optogenetics has ushered in a new era in neuroscience where spatiotemporal control of neurons is possible through light application. These tools used to study neural circuits can also be used therapeutically to restore vision. In order to recapitulate the broad spectral and light sensitivities along with high temporal sensitivity found in human vision, researchers have identified and developed new optogenetic tools. There are two major kinds of optogenetic effectors employed in vision restoration: ion channels and G-protein coupled receptors (GPCRs). Ion channel based optogenetic therapies require high intensity light that can be unsafe at lower wavelengths, so work has been done to expand and red-shift the excitation spectra of these channels. Light activatable GPCRs are much more sensitive to light than their ion channel counterparts but are slower kinetically in terms of both activation and inactivation. This review article examines the latest optogenetic ion channel and GPCR candidates for vision restoration based on light and temporal sensitivity.
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Affiliation(s)
- Cameron K. Baker
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, United States
| | - John G. Flannery
- School of Optometry, University of California, Berkeley, Berkeley, CA, United States
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29
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Sakajiri Y, Sugano E, Watanabe Y, Sakajiri T, Tabata K, Kikuchi T, Tomita H. Natronomonas pharaonis halorhodopsin Ser81 plays a role in maintaining chloride ions near the Schiff base. Biochem Biophys Res Commun 2018; 503:2326-2332. [PMID: 29964009 DOI: 10.1016/j.bbrc.2018.06.156] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 06/27/2018] [Indexed: 02/02/2023]
Abstract
Optogenetic technologies have often been used as tools for neuronal activation or silencing by light. Natronomonas pharaonis halorhodopsin (NpHR) is a light-driven chloride ion pump. Upon light absorption, a chloride ion passes through the cell membrane, which is accompanied by the temporary binding of a chloride ion with Thr126 at binding site-1 (BS1) near the protonated Schiff base in NpHR. However, the mechanism of stabilization of the binding state between a chloride ion and BS1 has not been investigated. Therefore, to identify a key component of the chloride ion transport pathway as well as to acquire dynamic information about the chloride ion-BS1 binding state, we performed a rough analysis of the chloride ion pathway shape followed by molecular dynamics (MD) simulations for both wild-type and mutant NpHR structures. The MD simulations showed that the hydrogen bond between Thr126 and the chloride ion was retained in the wild-type protein, while the chloride ion could not be retained at and tended to leave BS1 in the S81A mutant. We found that the direction of the Thr126 side chain was fixed by a hydroxyl group of Ser81 through a hydrogen bond and that Thr126 bound to a chloride ion in the wild-type protein, while this interaction was lost in the S81A mutant, resulting in rotation of the Thr126 side chain and reduction in the interaction between Thr126 and a chloride ion. To confirm the role of S81, patch clamp recordings were performed using cells expressing NpHR S81A mutant protein. Considered together with the results that the NpHR S81A-expressing cells did not undergo hyperpolarization under light stimulation, our results indicate that Ser81 plays a key role in chloride migration. Our findings might be relevant to ongoing clinical trials using optogenetic gene therapy in blind patients.
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Affiliation(s)
- Yuko Sakajiri
- The United Graduate School of Agricultural Sciences, Iwate University, 3-18-8 Ueda, Morioka, Iwate, 020-8550, Japan.
| | - Eriko Sugano
- The United Graduate School of Agricultural Sciences, Iwate University, 3-18-8 Ueda, Morioka, Iwate, 020-8550, Japan; Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University, 4-3-5 Ueda, Morioka, Iwate, 020-8551, Japan.
| | - Yoshito Watanabe
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University, 4-3-5 Ueda, Morioka, Iwate, 020-8551, Japan.
| | - Tetsuya Sakajiri
- Department of Applied Life Sciences, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka, 599-8531, Japan.
| | - Kitako Tabata
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University, 4-3-5 Ueda, Morioka, Iwate, 020-8551, Japan.
| | - Takeshi Kikuchi
- Department of Bioinformatics, College of Life Sciences, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu Shiga, 525-8577, Japan.
| | - Hiroshi Tomita
- The United Graduate School of Agricultural Sciences, Iwate University, 3-18-8 Ueda, Morioka, Iwate, 020-8550, Japan; Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University, 4-3-5 Ueda, Morioka, Iwate, 020-8551, Japan; Clinical Research, Innovation and Education Center, Tohoku University Hospital, 1-1 Seiryo, Aoba, Sendai, Miyagi, 980-8574, Japan.
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30
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Simunovic MP, Shen W, Lin JY, Protti DA, Lisowski L, Gillies MC. Optogenetic approaches to vision restoration. Exp Eye Res 2018; 178:15-26. [PMID: 30218651 DOI: 10.1016/j.exer.2018.09.003] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 08/16/2018] [Accepted: 09/07/2018] [Indexed: 10/28/2022]
Abstract
Inherited retinal disease (IRD) affects about 1 in 3000 to 1 in 5000 individuals and is now believed to be the most common cause of blindness registration in developed countries. Until recently, the management of such conditions had been exclusively supportive. However, advances in molecular biology and medical engineering have now seen the rise of a variety of approaches to restore vision in patients with IRDs. Optogenetic approaches are primarily aimed at rendering secondary and tertiary neurons of the retina light-sensitive in order to replace degenerate or dysfunctional photoreceptors. Such approaches are attractive because they provide a "causative gene-independent" strategy, which may prove suitable for a variety of patients with IRD. We discuss theoretical and practical considerations in the selection of optogenetic molecules, vectors, surgical approaches and review previous trials of optogenetics for vision restoration. Optogenetic approaches to vision restoration have yielded promising results in pre-clinical trials and a phase I/II clinical trial is currently underway (ClinicalTrials.gov NCT02556736). Despite the significant inroads made in recent years, the ideal optogenetic molecule, vector and surgical approach have yet to be established.
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Affiliation(s)
- M P Simunovic
- Save Sight Institute, University of Sydney, 8 Macquarie St., Sydney, NSW, 2000, Australia; Retinal Unit, Sydney Eye Hospital, 8 Macquarie St., Sydney, NSW, 2000, Australia.
| | - W Shen
- Retinal Unit, Sydney Eye Hospital, 8 Macquarie St., Sydney, NSW, 2000, Australia
| | - J Y Lin
- Faculty of Health, University of Tasmania, Private Bag 23, Hobart, TAS, 7000, Australia
| | - D A Protti
- Discipline of Physiology, University of Sydney, NSW, 2006, Australia
| | - L Lisowski
- Children's Medical Research Institute, University of Sydney, NSW, 2006, Australia; Military Institute of Hygiene and Epidemiology, 24-100, Puławy, Poland
| | - M C Gillies
- Save Sight Institute, University of Sydney, 8 Macquarie St., Sydney, NSW, 2000, Australia; Retinal Unit, Sydney Eye Hospital, 8 Macquarie St., Sydney, NSW, 2000, Australia
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31
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Lu Q, Ganjawala TH, Hattar S, Abrams GW, Pan ZH. A Robust Optomotor Assay for Assessing the Efficacy of Optogenetic Tools for Vision Restoration. Invest Ophthalmol Vis Sci 2018; 59:1288-1294. [PMID: 29625451 PMCID: PMC5839255 DOI: 10.1167/iovs.17-23278] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Purpose To develop an animal behavioral assay for the quantitative assessment of the functional efficacy of optogenetic therapies. Methods A triple-knockout (TKO) mouse line, Gnat1−/−Cnga3−/−Opn4−/−, and a double-knockout mouse line, Gnat1−/−Cnga3−/−, were employed. The expression of channelrhodopsin-2 (ChR2) and its three more light-sensitive mutants, ChR2-L132C, ChR2-L132C/T159C, and ChR2-132C/T159S, in inner retinal neurons was achieved using rAAV2 vectors via intravitreal delivery. Pupillary constriction was assessed by measuring the pupil diameter. The optomotor response (OMR) was examined using a homemade optomotor system equipped with light-emitting diodes as light stimulation. Results A robust OMR was restored in the ChR2-mutant-expressing TKO mice; however, significant pupillary constriction was observed only for the ChR2-L132C/T159S mutant. The ability to evoke an OMR was dependent on both the light intensity and grating frequency. The most light-sensitive frequency for the three ChR2 mutants was approximately 0.042 cycles per degree. Among the three ChR2 mutants, ChR2-L132C/T159S was the most light sensitive, followed by ChR2-L132C/T159C and ChR2-L132C. Melanopsin-mediated pupillary constriction resulted in a substantial reduction in the light sensitivity of the ChR2-mediated OMR. Conclusions The OMR assay using TKO mice enabled the quantitative assessment of the efficacy of different optogenetic tools and the properties of optogenetically restored vision. Thus, the assay can serve as a valuable tool for developing effective optogenetic therapies.
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Affiliation(s)
- Qi Lu
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan, United States.,Department of Ophthalmology, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Tushar H Ganjawala
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Samer Hattar
- National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland, United States
| | - Gary W Abrams
- Department of Ophthalmology, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Zhuo-Hua Pan
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan, United States.,Department of Ophthalmology, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, Michigan, United States
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32
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Watanabe Y, Sugano E, Tabata K, Ozaki T, Saito T, Tamai M, Tomita H. Kinetic profiles of photocurrents in cells expressing two types of channelrhodopsin genes. Biochem Biophys Res Commun 2018; 496:814-819. [PMID: 29395082 DOI: 10.1016/j.bbrc.2018.01.149] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 01/24/2018] [Indexed: 12/21/2022]
Abstract
Channelrhodopsin-2 (ChR2), a light-activated cation-selective ion channel, has been widely used as a tool in optogenetic research. ChR2 is specifically sensitive to wavelengths less than 550 nm. One of the methods to expand the sensitivity of a channelrhodopsin to a wider range of wavelengths is to express another channelrhodopsin in the cells by the transduction of an additional gene. Here, we report the characteristic features of cells expressing two types of channelrhodopsins, each having different wavelength sensitivities. In HEK293 cells stably expressing ChR2, photocurrents were elicited at stimuli of 400-550 nm, and the wavelength sensitivity range was expanded by the additional transduction of the modified Volvox channelrhodopsin-1 (mVChR1) gene, which has broad wavelength sensitivities, ranging from 400 to 600 nm. However, the photocurrent at 550 nm was lower than that of the mVChR1-expressing cell; moreover, the turning-on and turning-off constants were delayed, and the deactivation rates were decreased. Meanwhile, the response to lower light intensity was improved by the additional gene. Thus, the transduction of an additional gene is a useful method to improve the light and wavelength sensitivities, as well as photocurrent kinetic profiles, of channelrhodopsins.
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Affiliation(s)
- Yoshito Watanabe
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate, 020-8551, Japan.
| | - Eriko Sugano
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate, 020-8551, Japan; Soft-Path Engineering Research Center (SPERC), Iwate University Division of Science and Engineering, Morioka, 020-8551, Japan.
| | - Kitako Tabata
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate, 020-8551, Japan.
| | - Taku Ozaki
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate, 020-8551, Japan; Soft-Path Engineering Research Center (SPERC), Iwate University Division of Science and Engineering, Morioka, 020-8551, Japan.
| | - Takehiko Saito
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate, 020-8551, Japan.
| | - Makoto Tamai
- Tohoku University Graduate School of Medicine, 1-1 Seiryo, Aoba, Sendai, Miyagi, 980-8574, Japan.
| | - Hiroshi Tomita
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate, 020-8551, Japan; Soft-Path Engineering Research Center (SPERC), Iwate University Division of Science and Engineering, Morioka, 020-8551, Japan; Clinical Research, Innovation and Education Center, Tohoku University Hospital, 1-1 Seiryo, Aoba, Sendai, Miyagi, 980-8574, Japan.
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33
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Cheong SK, Xiong W, Strazzeri JM, Cepko CL, Williams DR, Merigan WH. In Vivo Functional Imaging of Retinal Neurons Using Red and Green Fluorescent Calcium Indicators. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1074:135-144. [PMID: 29721937 PMCID: PMC7856913 DOI: 10.1007/978-3-319-75402-4_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2023]
Abstract
Adaptive optics retinal imaging of fluorescent calcium indicators is a minimally invasive method used to study retinal physiology over extended periods of time. It has potential for discovering novel retinal circuits, tracking retinal function in animal models of retinal disease, and assessing vision restoration therapy. We previously demonstrated functional adaptive optics imaging of retinal neurons in the living eye using green fluorescent calcium indicators; however, the use of green fluorescent indicators presents challenges that stem from the fact that they are excited by short-wavelength light. Using red fluorescent calcium indicators such as jRGECO1a, which is excited with longer-wavelength light (~560 nm), makes imaging approximately five times safer than using short-wavelength light (~500 nm) used to excite green fluorescent calcium indicators such as GCaMP6s. Red fluorescent indicators also provide alternative wavelength imaging regimes to overcome cross talk with the sensitivities of intrinsic photoreceptors and blue light-activated channelrhodopsins. Here we evaluate jRGECO1a for in vivo functional adaptive optics imaging of retinal neurons using single-photon excitation in mice. We find that jRGECO1a provides similar fidelity as the established green indicator GCaMP6s.
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Affiliation(s)
- Soon K Cheong
- Center for Visual Science, University of Rochester, Rochester, NY, USA
- Flaum Eye Institute, University of Rochester, Rochester, NY, USA
| | - Wenjun Xiong
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon, Hong Kong SAR, China
| | - Jennifer M Strazzeri
- Center for Visual Science, University of Rochester, Rochester, NY, USA
- Flaum Eye Institute, University of Rochester, Rochester, NY, USA
| | - Constance L Cepko
- Departments of Genetics and Ophthalmology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - David R Williams
- Center for Visual Science, University of Rochester, Rochester, NY, USA
- Institute of Optics, University of Rochester, Rochester, NY, USA
| | - William H Merigan
- Center for Visual Science, University of Rochester, Rochester, NY, USA.
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34
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Chaffiol A, Caplette R, Jaillard C, Brazhnikova E, Desrosiers M, Dubus E, Duhamel L, Macé E, Marre O, Benoit P, Hantraye P, Bemelmans AP, Bamberg E, Duebel J, Sahel JA, Picaud S, Dalkara D. A New Promoter Allows Optogenetic Vision Restoration with Enhanced Sensitivity in Macaque Retina. Mol Ther 2017; 25:2546-2560. [PMID: 28807567 PMCID: PMC5675708 DOI: 10.1016/j.ymthe.2017.07.011] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 07/15/2017] [Accepted: 07/16/2017] [Indexed: 01/28/2023] Open
Abstract
The majority of inherited retinal degenerations converge on the phenotype of photoreceptor cell death. Second- and third-order neurons are spared in these diseases, making it possible to restore retinal light responses using optogenetics. Viral expression of channelrhodopsin in the third-order neurons under ubiquitous promoters was previously shown to restore visual function, albeit at light intensities above illumination safety thresholds. Here, we report (to our knowledge, for the first time) activation of macaque retinas, up to 6 months post-injection, using channelrhodopsin-Ca2+-permeable channelrhodopsin (CatCh) at safe light intensities. High-level CatCh expression was achieved due to a new promoter based on the regulatory region of the gamma-synuclein gene (SNCG) allowing strong expression in ganglion cells across species. Our promoter, in combination with clinically proven adeno-associated virus 2 (AAV2), provides CatCh expression in peri-foveolar ganglion cells responding robustly to light under the illumination safety thresholds for the human eye. On the contrary, the threshold of activation and the proportion of unresponsive cells were much higher when a ubiquitous promoter (cytomegalovirus [CMV]) was used to express CatCh. The results of our study suggest that the inclusion of optimized promoters is key in the path to clinical translation of optogenetics.
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Affiliation(s)
- Antoine Chaffiol
- INSERM U968, Institut de la Vision, 75012 Paris, France; UMRS968, Institut de la Vision, Sorbonne Universités, Pierre et Marie Curie University (UPMC) University Paris 06, 75012 Paris, France; Centre National de la Recherche Scientifique (CNRS) UMR7210, Institut de la Vision, 75012 Paris, France
| | - Romain Caplette
- INSERM U968, Institut de la Vision, 75012 Paris, France; UMRS968, Institut de la Vision, Sorbonne Universités, Pierre et Marie Curie University (UPMC) University Paris 06, 75012 Paris, France; Centre National de la Recherche Scientifique (CNRS) UMR7210, Institut de la Vision, 75012 Paris, France
| | - Céline Jaillard
- INSERM U968, Institut de la Vision, 75012 Paris, France; UMRS968, Institut de la Vision, Sorbonne Universités, Pierre et Marie Curie University (UPMC) University Paris 06, 75012 Paris, France; Centre National de la Recherche Scientifique (CNRS) UMR7210, Institut de la Vision, 75012 Paris, France
| | - Elena Brazhnikova
- INSERM U968, Institut de la Vision, 75012 Paris, France; UMRS968, Institut de la Vision, Sorbonne Universités, Pierre et Marie Curie University (UPMC) University Paris 06, 75012 Paris, France; Centre National de la Recherche Scientifique (CNRS) UMR7210, Institut de la Vision, 75012 Paris, France
| | - Mélissa Desrosiers
- INSERM U968, Institut de la Vision, 75012 Paris, France; UMRS968, Institut de la Vision, Sorbonne Universités, Pierre et Marie Curie University (UPMC) University Paris 06, 75012 Paris, France; Centre National de la Recherche Scientifique (CNRS) UMR7210, Institut de la Vision, 75012 Paris, France
| | - Elisabeth Dubus
- INSERM U968, Institut de la Vision, 75012 Paris, France; UMRS968, Institut de la Vision, Sorbonne Universités, Pierre et Marie Curie University (UPMC) University Paris 06, 75012 Paris, France; Centre National de la Recherche Scientifique (CNRS) UMR7210, Institut de la Vision, 75012 Paris, France
| | - Laëtitia Duhamel
- INSERM U968, Institut de la Vision, 75012 Paris, France; UMRS968, Institut de la Vision, Sorbonne Universités, Pierre et Marie Curie University (UPMC) University Paris 06, 75012 Paris, France; Centre National de la Recherche Scientifique (CNRS) UMR7210, Institut de la Vision, 75012 Paris, France
| | - Emilie Macé
- INSERM U968, Institut de la Vision, 75012 Paris, France; UMRS968, Institut de la Vision, Sorbonne Universités, Pierre et Marie Curie University (UPMC) University Paris 06, 75012 Paris, France; Centre National de la Recherche Scientifique (CNRS) UMR7210, Institut de la Vision, 75012 Paris, France
| | - Olivier Marre
- INSERM U968, Institut de la Vision, 75012 Paris, France; UMRS968, Institut de la Vision, Sorbonne Universités, Pierre et Marie Curie University (UPMC) University Paris 06, 75012 Paris, France; Centre National de la Recherche Scientifique (CNRS) UMR7210, Institut de la Vision, 75012 Paris, France
| | - Patrick Benoit
- Sanofi Ophthalmology Unit, 17 rue Moreau, 75012 Paris, France
| | - Philippe Hantraye
- Département des Sciences du Vivant (DSV), MIRCen, Institut d'Imagerie Biomédicale (I2BM), Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), Fontenay-aux-Roses 92260, France; Neurodegenerative Diseases Laboratory, CNRS UMR9199, Université Paris-Sud, Université Paris-Saclay, Fontenay-aux-Roses 92260, France
| | - Alexis-Pierre Bemelmans
- Département des Sciences du Vivant (DSV), MIRCen, Institut d'Imagerie Biomédicale (I2BM), Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), Fontenay-aux-Roses 92260, France; Neurodegenerative Diseases Laboratory, CNRS UMR9199, Université Paris-Sud, Université Paris-Saclay, Fontenay-aux-Roses 92260, France
| | - Ernst Bamberg
- Department of Biophysical Chemistry, Max Planck Institute of Biophysics, 60438 Frankfurt am Main, Germany
| | - Jens Duebel
- INSERM U968, Institut de la Vision, 75012 Paris, France; UMRS968, Institut de la Vision, Sorbonne Universités, Pierre et Marie Curie University (UPMC) University Paris 06, 75012 Paris, France; Centre National de la Recherche Scientifique (CNRS) UMR7210, Institut de la Vision, 75012 Paris, France.
| | - José-Alain Sahel
- INSERM U968, Institut de la Vision, 75012 Paris, France; UMRS968, Institut de la Vision, Sorbonne Universités, Pierre et Marie Curie University (UPMC) University Paris 06, 75012 Paris, France; Centre National de la Recherche Scientifique (CNRS) UMR7210, Institut de la Vision, 75012 Paris, France; CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS CIC, 28 rue de Charenton, 75012 Paris, France; Fondation Ophtalmologique Adolphe de Rothschild, 75019 Paris, France.
| | - Serge Picaud
- INSERM U968, Institut de la Vision, 75012 Paris, France; UMRS968, Institut de la Vision, Sorbonne Universités, Pierre et Marie Curie University (UPMC) University Paris 06, 75012 Paris, France; Centre National de la Recherche Scientifique (CNRS) UMR7210, Institut de la Vision, 75012 Paris, France.
| | - Deniz Dalkara
- INSERM U968, Institut de la Vision, 75012 Paris, France; UMRS968, Institut de la Vision, Sorbonne Universités, Pierre et Marie Curie University (UPMC) University Paris 06, 75012 Paris, France; Centre National de la Recherche Scientifique (CNRS) UMR7210, Institut de la Vision, 75012 Paris, France.
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35
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Tshilenge KT, Ameline B, Weber M, Mendes-Madeira A, Nedellec S, Biget M, Provost N, Libeau L, Blouin V, Deschamps JY, Le Meur G, Colle MA, Moullier P, Pichard V, Rolling F. Vitrectomy Before Intravitreal Injection of AAV2/2 Vector Promotes Efficient Transduction of Retinal Ganglion Cells in Dogs and Nonhuman Primates. Hum Gene Ther Methods 2017; 27:122-34. [PMID: 27229628 DOI: 10.1089/hgtb.2016.034] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Recombinant adeno-associated virus (AAV) has emerged as a promising vector for retinal gene delivery to restore visual function in certain forms of inherited retinal dystrophies. Several studies in rodent models have shown that intravitreal injection of the AAV2/2 vector is the optimal route for efficient retinal ganglion cell (RGC) transduction. However, translation of these findings to larger species, including humans, is complicated by anatomical differences in the eye, a key difference being the comparatively smaller volume of the vitreous chamber in rodents. Here, we address the role of the vitreous body as a potential barrier to AAV2/2 diffusion and transduction in the RGCs of dogs and macaques, two of the most relevant preclinical models. We intravitreally administered the AAV2/2 vector carrying the CMV-eGFP reporter cassette in dog and macaque eyes, either directly into the vitreous chamber or after complete vitrectomy, a surgical procedure that removes the vitreous body. Our findings suggest that the vitreous body appears to trap the injected vector, thus impairing the diffusion and transduction of AAV2/2 to inner retinal neurons. We show that vitrectomy before intravitreal vector injection is an effective means of overcoming this physical barrier, improving the transduction of RGCs in dog and macaque retinas. These findings support the use of vitrectomy in clinical trials of intravitreal gene transfer techniques targeting inner retinal neurons.
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Affiliation(s)
| | - Baptiste Ameline
- 1 Atlantic Gene Therapies, INSERM UMR 1089, Université de Nantes, CHU de Nantes, Nantes, France
| | - Michel Weber
- 2 CHU de Nantes, Service d'Ophtalmologie, Nantes, France
| | | | - Steven Nedellec
- 3 Cellular and Tissular Imaging Core Facility of Nantes University, SFR Santé Francois Bonamy INSERM UMS016/CNRS UMS3556, Nantes, France
| | - Marine Biget
- 1 Atlantic Gene Therapies, INSERM UMR 1089, Université de Nantes, CHU de Nantes, Nantes, France
| | - Nathalie Provost
- 1 Atlantic Gene Therapies, INSERM UMR 1089, Université de Nantes, CHU de Nantes, Nantes, France
| | - Lyse Libeau
- 1 Atlantic Gene Therapies, INSERM UMR 1089, Université de Nantes, CHU de Nantes, Nantes, France
| | - Véronique Blouin
- 1 Atlantic Gene Therapies, INSERM UMR 1089, Université de Nantes, CHU de Nantes, Nantes, France
| | - Jack-Yves Deschamps
- 4 Emergency and Critical Care Unit, ONIRIS, Nantes-Atlantic College of Veterinary Medicine Food Science and Engineering, Nantes, France
| | | | - Marie-Anne Colle
- 5 UMR 703 PAnTher INRA/ONIRIS, Nantes-Atlantic College of Veterinary Medicine Food Science and Engineering, Nantes, France
| | - Philippe Moullier
- 1 Atlantic Gene Therapies, INSERM UMR 1089, Université de Nantes, CHU de Nantes, Nantes, France.,6 Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida , Gainesville, Florida
| | - Virginie Pichard
- 1 Atlantic Gene Therapies, INSERM UMR 1089, Université de Nantes, CHU de Nantes, Nantes, France
| | - Fabienne Rolling
- 1 Atlantic Gene Therapies, INSERM UMR 1089, Université de Nantes, CHU de Nantes, Nantes, France
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36
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You M, Yamane T, Tomita H, Sugano E, Akashi T. A novel rat head gaze determination system based on optomotor responses. PLoS One 2017; 12:e0176633. [PMID: 28445553 PMCID: PMC5405982 DOI: 10.1371/journal.pone.0176633] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 04/13/2017] [Indexed: 02/07/2023] Open
Abstract
The optomotor response of animals is commonly used to measure their visual performance, e.g., rats of different genetically altered strains or various drug tests. With the presentation of stimuli using computer screens or projectors, the common idea focuses on measuring the eye movement or head and/or body movement to characterize changes of the head gaze. However, traditional methods rely on either the invasive fixation of animals, or the judgment of a human observer who reports the stimulus-tracking movements. In this paper, we propose a novel head gaze determination system to automatically track the head movement of rats without artificial markers. The experiments were done to demonstrate the process of optimizing parameters in image processing. As a result, the head angle curve of the proposed method is consistent with that of ground-truth data annotated manually according to predefined rules. Hence, the proposed method provides a simple, convenient, and objective solution to automatically generate the head gaze orientations from massive amounts of recorded data for further visual performance analysis.
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Affiliation(s)
- Mengbo You
- Department of Design and Media Technology, Graduate School of Engineering, Iwate University, Morioka, Iwate, Japan
| | - Toshiyuki Yamane
- Department of Chemistry and Biological Sciences, Faculty of Science and Engineering, Iwate University, Morioka, Iwate, Japan
| | - Hiroshi Tomita
- Department of Chemistry and Biological Sciences, Faculty of Science and Engineering, Iwate University, Morioka, Iwate, Japan
| | - Eriko Sugano
- Department of Chemistry and Biological Sciences, Faculty of Science and Engineering, Iwate University, Morioka, Iwate, Japan
| | - Takuya Akashi
- Department of Design and Media Technology, Graduate School of Engineering, Iwate University, Morioka, Iwate, Japan
- * E-mail:
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37
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Sato M, Sugano E, Tabata K, Sannohe K, Watanabe Y, Ozaki T, Tamai M, Tomita H. Visual Responses of Photoreceptor-Degenerated Rats Expressing Two Different Types of Channelrhodopsin Genes. Sci Rep 2017; 7:41210. [PMID: 28112267 PMCID: PMC5255552 DOI: 10.1038/srep41210] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 12/16/2016] [Indexed: 12/02/2022] Open
Abstract
Optogenetic technologies are expected to be applicable for clinical use in restoring vision. However, the degree of recovered visual function is highly dependent on the function of the chosen optogenetic gene. To investigate the effect on visual function of dual expression of genes with different wavelength sensitivities, we transduced a modified Volvox-derived channelrhodopsin gene (mVChR1) via an adeno-associated virus vector into transgenic rats harbouring the ChR2 gene in retinal ganglion cells. These transgenic rats were given an intraperitoneal injection of N-methyl-N-nitrosourea to induce the degeneration of native photoreceptor cells prior to transduction of mVChR1. Optical coherence tomography images indicated the degeneration of the native photoreceptor cells after the N-methyl-N-nitrosourea injection. Complete loss of function of the native photoreceptor cells was confirmed using electroretinograms. In the ChR2 transgenic rats, visually evoked potentials were clearly detectable in spite of native photoreceptor function abolishment; however the responses were limited to within blue wavelengths. In contrast, the limited wavelength sensitivities were improved by the additional transduction of mVChR1, which exhibited sensitivities to green and red. Thus, the transductions of dual genes encoding channelrhodopsins that exhibit different wavelength sensitivities represents a promising candidate method to expand and to enhance rescued wavelength sensitivities in blind subjects.
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Affiliation(s)
- Masatoshi Sato
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan
| | - Eriko Sugano
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan.,Soft-Path Engineering Research Center (SPERC), Iwate University Division of Science and Engineering, Morioka 020-8551, Japan
| | - Kitako Tabata
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan
| | - Kei Sannohe
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan
| | - Yoshito Watanabe
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan
| | - Taku Ozaki
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan.,Soft-Path Engineering Research Center (SPERC), Iwate University Division of Science and Engineering, Morioka 020-8551, Japan
| | - Makoto Tamai
- Tohoku University Graduate School of Medicine, 1-1 Seiryo, Aoba, Sendai, Miyagi 980-8574, Japan
| | - Hiroshi Tomita
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan.,Soft-Path Engineering Research Center (SPERC), Iwate University Division of Science and Engineering, Morioka 020-8551, Japan.,Clinical Research, Innovation and Education Center, Tohoku University Hospital, 1-1 Seiryo, Aoba, Sendai, Miyagi 980-8574, Japan
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38
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Sengupta A, Chaffiol A, Macé E, Caplette R, Desrosiers M, Lampič M, Forster V, Marre O, Lin JY, Sahel JA, Picaud S, Dalkara D, Duebel J. Red-shifted channelrhodopsin stimulation restores light responses in blind mice, macaque retina, and human retina. EMBO Mol Med 2016; 8:1248-1264. [PMID: 27679671 PMCID: PMC5090658 DOI: 10.15252/emmm.201505699] [Citation(s) in RCA: 113] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 08/09/2016] [Accepted: 08/11/2016] [Indexed: 01/31/2023] Open
Abstract
Targeting the photosensitive ion channel channelrhodopsin-2 (ChR2) to the retinal circuitry downstream of photoreceptors holds promise in treating vision loss caused by retinal degeneration. However, the high intensity of blue light necessary to activate channelrhodopsin-2 exceeds the safety threshold of retinal illumination because of its strong potential to induce photochemical damage. In contrast, the damage potential of red-shifted light is vastly lower than that of blue light. Here, we show that a red-shifted channelrhodopsin (ReaChR), delivered by AAV injections in blind rd1 mice, enables restoration of light responses at the retinal, cortical, and behavioral levels, using orange light at intensities below the safety threshold for the human retina. We further show that postmortem macaque retinae infected with AAV-ReaChR can respond with spike trains to orange light at safe intensities. Finally, to directly address the question of translatability to human subjects, we demonstrate for the first time, AAV- and lentivirus-mediated optogenetic spike responses in ganglion cells of the postmortem human retina.
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Affiliation(s)
- Abhishek Sengupta
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Antoine Chaffiol
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Emilie Macé
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Romain Caplette
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Mélissa Desrosiers
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Maruša Lampič
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Valérie Forster
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Olivier Marre
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - John Y Lin
- School of Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - José-Alain Sahel
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
- Hôpital des Quinze-Vingts, Paris, France
| | - Serge Picaud
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Deniz Dalkara
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Jens Duebel
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
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39
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Tabata K, Sugano E, Murakami F, Yamashita T, Ozaki T, Tomita H. Improved transduction efficiencies of adeno-associated virus vectors by synthetic cell-permeable peptides. Biochem Biophys Res Commun 2016; 478:1732-8. [PMID: 27614311 DOI: 10.1016/j.bbrc.2016.09.014] [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: 08/30/2016] [Accepted: 09/02/2016] [Indexed: 12/01/2022]
Abstract
Various serotypes of adeno-associated virus (AAV) vectors have been used for gene therapy and as research tools. Among these serotypes, the AAV type 2 vector has been used successfully in human gene therapies. However, the transduction efficiency of AAV2 depends on the cell type, and this poses a problem in the efficacy of gene therapy. To improve the transduction efficiency of AAV2, we designed a small peptide consisting of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor peptide and the HIV-Tat sequence Tat-Y1068. Pre- or co-treatment of CYNOM-K1 cells from cynomolgus monkey embryo skin with Tat-Y1068 increased the transduction efficiencies in a dose-dependent manner and caused p38 phosphorylation. The transduction efficiency of AAV2 into the rat fibroblast cell line RAT-1 highly expressing EGFR was less than the transduction efficiency of AAV2 into CYNOM-K1 cells. Tat-Y1068 increased the transduction efficiency in RAT-1 cells in the same manner as in CYNOM-K1 cells. In conclusion, cell-permeable peptides possessing the EGFR tyrosine kinase inhibitor function might serve as a useful ingredient of AAV2 vector solution for increasing the transduction efficiency of gene therapies.
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Affiliation(s)
- Kitako Tabata
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan.
| | - Eriko Sugano
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan; Soft-Path Engineering Research Center (SPERC), Faculty of Engineering, Iwate University, Morioka, 020-8551, Japan.
| | - Fumika Murakami
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan.
| | - Tetsuro Yamashita
- Soft-Path Engineering Research Center (SPERC), Faculty of Engineering, Iwate University, Morioka, 020-8551, Japan; Department of Biological Chemistry, Iwate University Faculty of Agriculture, Morioka, Japan.
| | - Taku Ozaki
- Soft-Path Engineering Research Center (SPERC), Faculty of Engineering, Iwate University, Morioka, 020-8551, Japan.
| | - Hiroshi Tomita
- Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan; Soft-Path Engineering Research Center (SPERC), Faculty of Engineering, Iwate University, Morioka, 020-8551, Japan; Clinical Research, Innovation and Education Center, Tohoku University Hospital, 1-1 Seiryo, Aoba, Sendai, Miyagi 980-8574, Japan.
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40
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Klapper SD, Swiersy A, Bamberg E, Busskamp V. Biophysical Properties of Optogenetic Tools and Their Application for Vision Restoration Approaches. Front Syst Neurosci 2016; 10:74. [PMID: 27642278 PMCID: PMC5009148 DOI: 10.3389/fnsys.2016.00074] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 08/17/2016] [Indexed: 11/13/2022] Open
Abstract
Optogenetics is the use of genetically encoded light-activated proteins to manipulate cells in a minimally invasive way using light. The most prominent example is channelrhodopsin-2 (ChR2), which allows the activation of electrically excitable cells via light-dependent depolarization. The combination of ChR2 with hyperpolarizing-light-driven ion pumps such as the Cl(-) pump halorhodopsin (NpHR) enables multimodal remote control of neuronal cells in culture, tissue, and living animals. Very soon, it became obvious that this method offers a chance of gene therapy for many diseases affecting vision. Here, we will give a brief introduction to retinal function and retinal diseases; optogenetic vision restoration strategies will be highlighted. We will discuss the functional and structural properties of rhodopsin-based optogenetic tools and analyze the potential for the application of vision restoration.
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Affiliation(s)
- Simon D Klapper
- Center for Regenerative Therapies Dresden, Technische Universität Dresden Dresden, Germany
| | - Anka Swiersy
- Center for Regenerative Therapies Dresden, Technische Universität Dresden Dresden, Germany
| | - Ernst Bamberg
- Max Planck Institute of Biophysics Frankfurt, Germany
| | - Volker Busskamp
- Center for Regenerative Therapies Dresden, Technische Universität Dresden Dresden, Germany
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41
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Abstract
Severe loss of photoreceptor cells in inherited or acquired retinal degenerative diseases can result in partial loss of sight or complete blindness. The optogenetic strategy for restoration of vision utilizes optogenetic tools to convert surviving inner retinal neurons into photosensitive cells; thus, light sensitivity is imparted to the retina after the death of photoreceptor cells. Proof-of-concept studies, especially those using microbial rhodopsins, have demonstrated restoration of light responses in surviving retinal neurons and visually guided behaviors in animal models. Significant progress has also been made in improving microbial rhodopsin-based optogenetic tools, developing virus-mediated gene delivery, and targeting specific retinal neurons and subcellular compartments of retinal ganglion cells. In this article, we review the current status of the field and outline further directions and challenges to the advancement of this strategy toward clinical application and improvement in the outcomes of restored vision.
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Affiliation(s)
- Zhuo-Hua Pan
- Department of Ophthalmology, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, Michigan 48201; , , .,Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan 48201;
| | - Qi Lu
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan 48201;
| | - Anding Bi
- Department of Ophthalmology, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, Michigan 48201; , ,
| | | | - Gary W Abrams
- Department of Ophthalmology, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, Michigan 48201; , ,
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42
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Hososhima S, Yuasa H, Ishizuka T, Hoque MR, Yamashita T, Yamanaka A, Sugano E, Tomita H, Yawo H. Near-infrared (NIR) up-conversion optogenetics. Sci Rep 2015; 5:16533. [PMID: 26552717 PMCID: PMC4639720 DOI: 10.1038/srep16533] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 10/15/2015] [Indexed: 12/15/2022] Open
Abstract
Non-invasive remote control technologies designed to manipulate neural functions have been long-awaited for the comprehensive and quantitative understanding of neuronal network in the brain as well as for the therapy of neurological disorders. Recently, it has become possible for the neuronal activity to be optically manipulated using biological photo-reactive molecules such as channelrhodopsin (ChR)-2. However, ChR2 and its relatives are mostly reactive to visible light, which does not effectively penetrate through biological tissues. In contrast, near-infrared (NIR) light (650-1450 nm) penetrates deep into the tissues because biological systems are almost transparent to light within this so-called 'imaging window'. Here we used lanthanide nanoparticles (LNPs), composed of rare-earth elements, as luminous bodies to activate ChRs since they absorb low-energy NIR light to emit high-energy visible light (up-conversion). Here, we created a new type of optogenetic system which consists of the donor LNPs and the acceptor ChRs. The NIR laser irradiation emitted visible light from LNPs, then induced the photo-reactive responses in the near-by cells that expressed ChRs. However, there remains room for large improvements in the energy efficiency of the LNP-ChR system.
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Affiliation(s)
- Shoko Hososhima
- Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai 980-8577, Japan
| | - Hideya Yuasa
- Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan
| | - Toru Ishizuka
- Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai 980-8577, Japan
| | - Mohammad Razuanul Hoque
- Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai 980-8577, Japan
| | - Takayuki Yamashita
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
| | - Akihiro Yamanaka
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
| | - Eriko Sugano
- Laboratory of Visual Neuroscience, Department of Chemistry and Bioengineering, Iwate University Graduate School of Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan
| | - Hiroshi Tomita
- Laboratory of Visual Neuroscience, Department of Chemistry and Bioengineering, Iwate University Graduate School of Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan.,Clinical Research, Innovation and Education Center, Tohoku University Hospital, 1-1 Seiryo, Aoba, Sendai, Miyagi 980-8574, Japan
| | - Hiromu Yawo
- Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai 980-8577, Japan.,Center for Neuroscience, Tohoku University Graduate School of Medicine, Sendai 980-8575, Japan
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43
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Local and systemic responses following intravitreous injection of AAV2-encoded modified Volvox channelrhodopsin-1 in a genetically blind rat model. Gene Ther 2015; 23:158-66. [PMID: 26440056 DOI: 10.1038/gt.2015.99] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 08/11/2015] [Accepted: 09/04/2015] [Indexed: 01/22/2023]
Abstract
We previously designed a modified channelrhodopsin-1 (mVChR1) protein chimera with a broader action than that of Chlamydomonas channelrhodopsin-2 and reported that its transduction into retinal ganglion cells can restore visual function in genetically blind, dystrophic Royal College of Surgeons (RCS) rats, with photostimuli ranging from 486 to 640 nm. In the current study, we sought to investigate the safety and influence of mVChR1 transgene expression. Adeno-associated virus type 2 encoding mVChR1 was administered by intravitreous injection into dystrophic RCS rats. Reverse-transcription PCR was used to monitor virus and transgene dissemination and the results demonstrated that their expression was restricted specifically within the eye tissues, and not in non-target organs. Moreover, examination of the blood, plasma and serum revealed that no excess immunoreactivity was present, as determined using standard clinical hematological parameters. Serum antibodies targeting the recombinant adeno-associated virus (rAAV) capsid increased after the injection; however, no increase in mVChR1 antibody was detected during the observation period. In addition, retinal histological examination showed no signs of inflammation in rAAV-injected rats. In conclusion, our results demonstrate that mVChR1 can be exogenously expressed without harmful immunological reactions in vivo. These findings will aid in studies of AAV gene transfer to restore vision in late-stage retinitis pigmentosa.
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Retinal gene delivery by adeno-associated virus (AAV) vectors: Strategies and applications. Eur J Pharm Biopharm 2015; 95:343-52. [DOI: 10.1016/j.ejpb.2015.01.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 01/10/2015] [Accepted: 01/12/2015] [Indexed: 11/20/2022]
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