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Zhang KY, Nagalingam A, Mary S, Aguzzi EA, Li W, Chetla N, Smith B, Paulaitis ME, Edwards MM, Quigley HA, Zack DJ, Johnson TV. Rare intercellular material transfer as a confound to interpreting inner retinal neuronal transplantation following internal limiting membrane disruption. Stem Cell Reports 2023; 18:2203-2221. [PMID: 37802075 PMCID: PMC10679651 DOI: 10.1016/j.stemcr.2023.09.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 09/07/2023] [Accepted: 09/08/2023] [Indexed: 10/08/2023] Open
Abstract
Intercellular cytoplasmic material transfer (MT) occurs between transplanted and developing photoreceptors and ambiguates cell origin identification in developmental, transdifferentiation, and transplantation experiments. Whether MT is a photoreceptor-specific phenomenon is unclear. Retinal ganglion cell (RGC) replacement, through transdifferentiation or transplantation, holds potential for restoring vision in optic neuropathies. During careful assessment for MT following human stem cell-derived RGC transplantation into mice, we identified RGC xenografts occasionally giving rise to labeling of donor-derived cytoplasmic, nuclear, and mitochondrial proteins within recipient Müller glia. Critically, nuclear organization is distinct between human and murine retinal neurons, which enables unequivocal discrimination of donor from host cells. MT was greatly facilitated by internal limiting membrane disruption, which also augments retinal engraftment following transplantation. Our findings demonstrate that retinal MT is not unique to photoreceptors and challenge the isolated use of species-specific immunofluorescent markers for xenotransplant identification. Assessment for MT is critical when analyzing neuronal replacement interventions.
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Affiliation(s)
- Kevin Y Zhang
- Glaucoma Center for Excellence, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Arumugam Nagalingam
- Glaucoma Center for Excellence, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Stella Mary
- Glaucoma Center for Excellence, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Erika A Aguzzi
- Glaucoma Center for Excellence, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Weifeng Li
- Glaucoma Center for Excellence, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Nitin Chetla
- Glaucoma Center for Excellence, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Barbara Smith
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Michael E Paulaitis
- Center for Nanomedicine, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Malia M Edwards
- Glaucoma Center for Excellence, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Harry A Quigley
- Glaucoma Center for Excellence, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Donald J Zack
- Glaucoma Center for Excellence, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Departments of Neuroscience, Molecular Biology and Genetics, and Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Thomas V Johnson
- Glaucoma Center for Excellence, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Cellular and Molecular Medicine Program, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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2
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Xie Y, Zhou J, Wang LL, Zhang CL, Chen B. New AAV tools fail to detect Neurod1-mediated neuronal conversion of Müller glia and astrocytes in vivo. EBioMedicine 2023; 90:104531. [PMID: 36947961 PMCID: PMC10033723 DOI: 10.1016/j.ebiom.2023.104531] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 03/03/2023] [Accepted: 03/03/2023] [Indexed: 03/24/2023] Open
Abstract
BACKGROUND Reprogramming resident glial cells to convert them into neurons in vivo represents a potential therapeutic strategy that could replenish lost neurons, repair damaged neural circuits, and restore function. AAV (adeno-associated virus)-based expression systems are powerful tools for in vivo gene delivery in glia-to-neuron reprogramming, however, recent studies show that AAV-based gene delivery of Neurod1 into the mouse brain can cause severe leaky expression into endogenous neurons leading to misinterpretation of glia-to-neuron conversion. METHODS AAV-based delivery systems were modified for improved in vivo delivery of Neurod1, Math5, Ascl1, and Neurog2 in the adult mouse retina and brain. To examine whether bona fide glia-to-neuron conversion occurs, stringent fate mapping experiments were performed to trace the lineage of glial cells. FINDINGS The neuronal leakage is prevalent after AAV-GFAP-mediated delivery of Neurod1, Math5, Ascl1, and Neurog2. The transgene-dependent leakage cannot be corrected after lowering the AAV doses, using alterative AAV serotypes or injection routes. Importantly, we report the development of two new AAV-based tools that can significantly reduce neuronal leakage. Using the new AAV-based tools, we provide evidence that Neurod1 gene transfer fails to convert lineage traced glial cells into neurons. INTERPRETATION Stringent fate mapping techniques independently of an AAV-based expression system are the golden standard for tracing the fate of glia cells during neuronal reprogramming. The newly developed AAV-based systems are invaluable tools for glia-to-neuron reprogramming in vivo. FUNDING The work in Chen lab was supported by National Institutes of Health (NIH) grants R01 EY024986 and R01 EY028921, an unrestricted challenge grant from Research to Prevent Blindness, the New York Eye and Ear Infirmary Foundation, and The Harold W. McGraw, Jr. Family Foundation for Vision Research. The work in Zhang lab was supported by NIH (R01 NS127375 and R01 NS117065) and The Decherd Foundation.
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Affiliation(s)
- Ye Xie
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Jing Zhou
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Lei-Lei Wang
- Department of Molecular Biology and Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Chun-Li Zhang
- Department of Molecular Biology and Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Bo Chen
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Department of Cell, Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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3
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Johnson TV, Polo AD, Sahel JA, Schuman JS. Neuroprotection, Neuroenhancement, and Neuroregeneration of the Retina and Optic Nerve. OPHTHALMOLOGY SCIENCE 2022; 2:100216. [PMID: 36245765 PMCID: PMC9559091 DOI: 10.1016/j.xops.2022.100216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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4
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Xue Y, Lin B, Chen JT, Tang WC, Browne AW, Seiler MJ. The Prospects for Retinal Organoids in Treatment of Retinal Diseases. Asia Pac J Ophthalmol (Phila) 2022; 11:314-327. [PMID: 36041146 PMCID: PMC9966053 DOI: 10.1097/apo.0000000000000538] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 04/22/2022] [Indexed: 12/28/2022] Open
Abstract
Retinal degeneration (RD) is a significant cause of incurable blindness worldwide. Photoreceptors and retinal pigmented epithelium are irreversibly damaged in advanced RD. Functional replacement of photoreceptors and/or retinal pigmented epithelium cells is a promising approach to restoring vision. This paper reviews the current status and explores future prospects of the transplantation therapy provided by pluripotent stem cell-derived retinal organoids (ROs). This review summarizes the status of rodent RD disease models and discusses RO culture and analytical tools to evaluate RO quality and function. Finally, we review and discuss the studies in which RO-derived cells or sheets were transplanted. In conclusion, methods to derive ROs from pluripotent stem cells have significantly improved and become more efficient in recent years. Meanwhile, more novel technologies are applied to characterize and validate RO quality. However, opportunity remains to optimize tissue differentiation protocols and achieve better RO reproducibility. In order to screen high-quality ROs for downstream applications, approaches such as noninvasive and label-free imaging and electrophysiological functional testing are promising and worth further investigation. Lastly, transplanted RO-derived tissues have allowed improvements in visual function in several RD models, showing promises for clinical applications in the future.
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Affiliation(s)
- Yuntian Xue
- Biomedical Engineering, University of California, Irvine, CA
- Stem Cell Research Center, University of California, Irvine, CA
| | - Bin Lin
- Stem Cell Research Center, University of California, Irvine, CA
| | - Jacqueline T. Chen
- Stem Cell Research Center, University of California, Irvine, CA
- Gavin Herbert Eye Institute Ophthalmology, University of California, Irvine, CA
| | - William C. Tang
- Biomedical Engineering, University of California, Irvine, CA
| | - Andrew W. Browne
- Biomedical Engineering, University of California, Irvine, CA
- Gavin Herbert Eye Institute Ophthalmology, University of California, Irvine, CA
- Institute for Clinical and Translational Science, University of California, Irvine, CA
| | - Magdalene J. Seiler
- Stem Cell Research Center, University of California, Irvine, CA
- Gavin Herbert Eye Institute Ophthalmology, University of California, Irvine, CA
- Department of Physical Medicine and Rehabilitation, University of California, Irvine, CA
- Department of Anatomy and Neurobiology, University of California, Irvine, CA
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5
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Xie Y, Zhou J, Chen B. Critical examination of Ptbp1-mediated glia-to-neuron conversion in the mouse retina. Cell Rep 2022; 39:110960. [PMID: 35705044 PMCID: PMC9371382 DOI: 10.1016/j.celrep.2022.110960] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 04/10/2022] [Accepted: 05/24/2022] [Indexed: 11/27/2022] Open
Abstract
Reprogramming glial cells to convert them into neurons represents a potential therapeutic strategy that could repair damaged neural circuits and restore function. Recent studies show that downregulation of the RNA-binding protein PTBP1 leads to one-step conversion of Müller glia (MG) into retinal ganglion cells (RGCs) with a high efficiency. However, the original study did not perform fate-mapping experiments to confirm MG-to-RGC conversion after Ptbp1 downregulation. To address the fundamental question of whether Ptbp1 downregulation can convert MG into RGCs in the mouse retina, we perform fate-mapping experiments to lineage trace MG independent of the adeno-associated virus (AAV)-mediated labeling system. Here, we report that Ptbp1 downregulation by CRISPR-CasRx or small hairpin RNA is insufficient to convert MG to RGCs. The original conclusion of MG-to-RGC conversion is due to leaky labeling of endogenous RGCs. Our results emphasize the importance of using stringent fate mapping to determine glia-to-neuron conversion in cell reprogramming research. Leaky labeling of endogenous retinal ganglion cells (RGCs) leads to misinterpretation of glia-to-neuron conversion in the mouse retina. Using stringent fate-mapping experiments, Xie et al. show that lineage-traced Müller glia (MG) are not converted into RGCs after Ptbp1 downregulation by CRISPR-CasRx or small hairpin RNA.
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Affiliation(s)
- Ye Xie
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Jing Zhou
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Bo Chen
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Department of Cell, Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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6
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Xie Y, Chen B. Critical Examination of Müller Glia-Derived in vivo Neurogenesis in the Mouse Retina. Front Cell Dev Biol 2022; 10:830382. [PMID: 35433694 PMCID: PMC9008276 DOI: 10.3389/fcell.2022.830382] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 02/10/2022] [Indexed: 01/02/2023] Open
Abstract
Müller glia (MG) are a potential source of stem cells in the mammalian retina that could replenish lost retinal neurons for vision restoration. Unlike their counterpart in zebrafish, mammalian MG are quiescent and they do not spontaneously generate new retinal neurons. In recent years, extensive research efforts have been made to unlock the regenerative capabilities of Müller glia (MG) for de novo regeneration of retinal neurons in mice. Here, we discuss current research progress on MG-derived in vivo neurogenesis in the mouse retina, focusing on the use of stringent fate mapping techniques to evaluate and validate de novo regeneration of retinal neurons through the reprogramming of endogenous MG. Establishing stringent experimental criteria is critical for examining current and future studies on MG-derived regeneration of photoreceptors, retinal inter-neurons, and retinal ganglion cells.
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7
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Shiau F, Ruzycki PA, Clark BS. A single-cell guide to retinal development: Cell fate decisions of multipotent retinal progenitors in scRNA-seq. Dev Biol 2021; 478:41-58. [PMID: 34146533 PMCID: PMC8386138 DOI: 10.1016/j.ydbio.2021.06.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 06/07/2021] [Accepted: 06/08/2021] [Indexed: 12/20/2022]
Abstract
Recent advances in high throughput single-cell RNA sequencing (scRNA-seq) technology have enabled the simultaneous transcriptomic profiling of thousands of individual cells in a single experiment. To investigate the intrinsic process of retinal development, researchers have leveraged this technology to quantify gene expression in retinal cells across development, in multiple species, and from numerous important models of human disease. In this review, we summarize recent applications of scRNA-seq and discuss how these datasets have complemented and advanced our understanding of retinal progenitor cell competence, cell fate specification, and differentiation. Finally, we also highlight the outstanding questions in the field that advances in single-cell data generation and analysis will soon be able to answer.
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Affiliation(s)
- Fion Shiau
- John F Hardesty, MD Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Philip A Ruzycki
- John F Hardesty, MD Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Brian S Clark
- John F Hardesty, MD Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA; Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA.
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8
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Blackshaw S, Sanes JR. Turning lead into gold: reprogramming retinal cells to cure blindness. J Clin Invest 2021; 131:146134. [PMID: 33529169 DOI: 10.1172/jci146134] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Affiliation(s)
- Seth Blackshaw
- Departments of Neuroscience.,Neurology, and.,Ophthalmology.,Institute for Cell Engineering, and.,Kavli Neuroscience Discovery Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Joshua R Sanes
- Center for Brain Science and.,Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts, USA
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9
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Chen Y, Fan Q, Zhang H, Tao D, Wang Y, Yue R, Sun Y. Lineage tracing of cells expressing the ciliary gene IFT140 during bone development. Dev Dyn 2021; 250:574-583. [PMID: 33095947 DOI: 10.1002/dvdy.266] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 09/28/2020] [Accepted: 10/17/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Primary cilia influence cell function and tissue development. Ciliary signaling is mediated by two intraflagellar transport (IFT) protein complexes, IFT-A and IFT-B. The IFT-A complex is responsible for retrograde transport, and IFT140 is a core protein in the A complex. Mutations in IFT140 cause a variety of skeletal disorders. However, the expression and role of IFT140 during bone development remain unclear. In this study, to further explore the potential role of IFT140 in osteogenesis, we used cell lineage tracing and conditional knockout to analyze the distribution and function of IFT140-positive cells during bone formation. RESULTS In newborn Ift140-creER; R26RtdTomato mice, IFT140-positive cells were mainly located in the medullary cavity and then migrated to and differentiated on the surface of trabecular and cortical bone. In contrast, the number of IFT140-positive cells significantly decreased in the adult stage, and these cells were only located in the bone marrow cavity for a short time. In Osx-cre; Ift140flox/flox mice, the loss of IFT140 in preosteoblasts caused bone loss in the trabecular bone area at 10 weeks. CONCLUSION The results revealed that IFT140-positive cells mainly contribute to the early stage of bone formation.
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Affiliation(s)
- Yubei Chen
- Department of Implantology, School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, China
| | - Qiqi Fan
- Department of Implantology, School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, China
| | - Han Zhang
- Department of Implantology, School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, China
| | - Dike Tao
- Department of Implantology, School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, China
| | - Yibin Wang
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Rui Yue
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Yao Sun
- Department of Implantology, School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, China
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10
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Oliveira-Valença VM, Bosco A, Vetter ML, Silveira MS. On the Generation and Regeneration of Retinal Ganglion Cells. Front Cell Dev Biol 2020; 8:581136. [PMID: 33043015 PMCID: PMC7527462 DOI: 10.3389/fcell.2020.581136] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 08/28/2020] [Indexed: 01/02/2023] Open
Abstract
Retinal development follows a conserved neurogenic program in vertebrates to orchestrate the generation of specific cell types from multipotent progenitors in sequential but overlapping waves. In this program, retinal ganglion cells (RGCs) are the first cell type generated. RGCs are the final output neurons of the retina and are essential for vision and circadian rhythm. Key molecular steps have been defined in multiple vertebrate species to regulate competence, specification, and terminal differentiation of this cell type. This involves neuronal-specific transcription factor networks, regulators of chromatin dynamics and miRNAs. In mammals, RGCs and their optic nerve axons undergo neurodegeneration and loss in glaucoma and other optic neuropathies, resulting in irreversible vision loss. The incapacity of RGCs and axons to regenerate reinforces the need for the design of efficient RGC replacement strategies. Here we describe the essential molecular pathways for the differentiation of RGCs in vertebrates, as well as experimental manipulations that extend the competence window for generation of this early cell type from late progenitors. We discuss recent advances in regeneration of retinal neurons in vivo in both mouse and zebrafish and discuss possible strategies and barriers to achieving RGC regeneration as a therapeutic approach for vision restoration in blinding diseases such as glaucoma.
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Affiliation(s)
- Viviane M Oliveira-Valença
- Laboratory of Neurogenesis, Neurobiology Program, Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Alejandra Bosco
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT, United States
| | - Monica L Vetter
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT, United States
| | - Mariana S Silveira
- Laboratory of Neurogenesis, Neurobiology Program, Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
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11
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Martin JF, Poché RA. Awakening the regenerative potential of the mammalian retina. Development 2019; 146:146/23/dev182642. [PMID: 31792065 DOI: 10.1242/dev.182642] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
As with all glial cells, the major role of retinal Müller glia (MG) is to provide essential neuronal support. However, the MG of some non-mammalian species have the additional ability to generate new retinal neurons capable of sight restoration. Unfortunately, mammalian MG do not possess this ability. However, if we could understand the reasons why, we may be able to devise strategies to confer regenerative potential. The recent discovery that the Hippo signaling pathway acts as an intrinsic block to mammalian MG proliferation, along with reports of adeno-associated virus (AAV)-based MG reprogramming and functional photoreceptor differentiation, may indicate a watershed moment in the field of mammalian retinal regeneration. However, as researchers delve deeper into the cellular and molecular mechanisms, and further refine MG reprogramming strategies, we should recall past misinterpretations of data in this field and proceed with caution. Here, we provide a summary of these emerging data and a discussion of technical concerns specific to AAV-mediated reprogramming experiments that must be addressed in order for the field to move forward.
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Affiliation(s)
- James F Martin
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA.,Development, Disease Models and Therapeutics Graduate Program, Baylor College of Medicine, Houston, TX 77030, USA.,Genetics and Genomics Graduate Program, Baylor College of Medicine, Houston, TX 77030, USA.,Cardiovasular Research Institute, Baylor College of Medicine, Houston, TX 77030, USA.,Texas Heart Institute, Cardiomyocyte Renewal Lab, Houston, TX 77030, USA
| | - Ross A Poché
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA .,Development, Disease Models and Therapeutics Graduate Program, Baylor College of Medicine, Houston, TX 77030, USA.,Genetics and Genomics Graduate Program, Baylor College of Medicine, Houston, TX 77030, USA
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12
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Abstract
Retinal degeneration is a leading cause of untreatable blindness in the industrialised world. It is typically irreversible and there are few curative treatments available. The use of stem cells to generate new retinal neurons for transplantation purposes has received significant interest in recent years and is beginning to move towards clinical trials. However, such approaches are likely to be most effective for relatively focal areas of repair. An intriguing complementary approach is endogenous self-repair. Retinal cells from the ciliary marginal zone (CMZ), retinal pigment epithelium (RPE) and Müller glial cells (MG) have all been shown to play a role in retinal repair, typically in lower vertebrates. Among them, MG have received renewed interest, due to their distribution throughout (centre to periphery) the neural retina and their potential to re-acquire a progenitor-like state following retinal injury with the ability to proliferate and generate new neurons. Triggering these innate self-repair mechanisms represents an exciting therapeutic option in treating retinal degeneration. However, these cells behave differently in mammalian and non-mammalian species, with a considerably restricted potential in mammals. In this short review, we look at some of the recent progress made in our understanding of the signalling pathways that underlie MG-mediated regeneration in lower vertebrates, and some of the challenges that have been revealed in our attempts to reactivate this process in the mammalian retina.
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Affiliation(s)
- Rahul Langhe
- Institute of Ophthalmology, University College London, London, UK
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13
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Rocha-Martins M, de Toledo BC, Santos-França PL, Oliveira-Valença VM, Vieira-Vieira CH, Matos-Rodrigues GE, Linden R, Norden C, Martins RAP, Silveira MS. De novo genesis of retinal ganglion cells by targeted expression of Klf4 in vivo. Development 2019; 146:dev.176586. [PMID: 31405994 DOI: 10.1242/dev.176586] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 07/09/2019] [Indexed: 12/11/2022]
Abstract
Retinal ganglion cell (RGC) degeneration is a hallmark of glaucoma, the most prevalent cause of irreversible blindness. Thus, therapeutic strategies are needed to protect and replace these projection neurons. One innovative approach is to promote de novo genesis of RGCs via manipulation of endogenous cell sources. Here, we demonstrate that the pluripotency regulator gene Krüppel-like factor 4 (Klf4) is sufficient to change the potency of lineage-restricted retinal progenitor cells to generate RGCs in vivo Transcriptome analysis disclosed that the overexpression of Klf4 induces crucial regulators of RGC competence and specification, including Atoh7 and Eya2 In contrast, loss-of-function studies in mice and zebrafish demonstrated that Klf4 is not essential for generation or differentiation of RGCs during retinogenesis. Nevertheless, induced RGCs (iRGCs) generated upon Klf4 overexpression migrate to the proper layer and project axons aligned with endogenous fascicles that reach the optic nerve head. Notably, iRGCs survive for up to 30 days after in vivo generation. We identified Klf4 as a promising candidate for reprogramming retinal cells and regenerating RGCs in the retina.This article has an associated 'The people behind the papers' interview.
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Affiliation(s)
- Maurício Rocha-Martins
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil .,Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Beatriz C de Toledo
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil
| | - Pedro L Santos-França
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil
| | - Viviane M Oliveira-Valença
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil
| | - Carlos H Vieira-Vieira
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil
| | - Gabriel E Matos-Rodrigues
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil
| | - Rafael Linden
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil
| | - Caren Norden
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Rodrigo A P Martins
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil
| | - Mariana S Silveira
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil
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14
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Devoldere J, Peynshaert K, De Smedt SC, Remaut K. Müller cells as a target for retinal therapy. Drug Discov Today 2019; 24:1483-1498. [PMID: 30731239 DOI: 10.1016/j.drudis.2019.01.023] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 12/20/2018] [Accepted: 01/30/2019] [Indexed: 12/28/2022]
Abstract
Müller cells are specialized glial cells that span the entire retina from the vitreous cavity to the subretinal space. Their functional diversity and unique radial morphology render them particularly interesting targets for new therapeutic approaches. In this review, we reflect on various possibilities for selective Müller cell targeting and describe how some of their cellular mechanisms can be used for retinal neuroprotection. Intriguingly, cross-species investigation of their properties has revealed that Müller cells also have an essential role in retinal regeneration. Although many questions regarding this subject remain, it is clear that Müller cells have unique characteristics that make them suitable targets for the prevention and treatment of numerous retinal diseases.
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Affiliation(s)
- Joke Devoldere
- Ghent Research Group on Nanomedicines, Laboratory of General Biochemistry and Physical Pharmacy, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium
| | - Karen Peynshaert
- Ghent Research Group on Nanomedicines, Laboratory of General Biochemistry and Physical Pharmacy, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium
| | - Stefaan C De Smedt
- Ghent Research Group on Nanomedicines, Laboratory of General Biochemistry and Physical Pharmacy, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium; Cancer Research Institute Ghent (CRIG), Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium
| | - Katrien Remaut
- Ghent Research Group on Nanomedicines, Laboratory of General Biochemistry and Physical Pharmacy, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium; Cancer Research Institute Ghent (CRIG), Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium.
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15
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Léveillard T, Klipfel L. Mechanisms Underlying the Visual Benefit of Cell Transplantation for the Treatment of Retinal Degenerations. Int J Mol Sci 2019; 20:ijms20030557. [PMID: 30696106 PMCID: PMC6387096 DOI: 10.3390/ijms20030557] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 01/23/2019] [Accepted: 01/24/2019] [Indexed: 12/13/2022] Open
Abstract
The transplantation of retinal cells has been studied in animals to establish proof of its potential benefit for the treatment of blinding diseases. Photoreceptor precursors have been grafted in animal models of Mendelian-inherited retinal degenerations, and retinal pigmented epithelial cells have been used to restore visual function in animal models of age-related macular degeneration (AMD) and recently in patients. Cell therapy over corrective gene therapy in inherited retinal degeneration can overcome the genetic heterogeneity by providing one treatment for all genetic forms of the diseases. In AMD, the existence of multiple risk alleles precludes a priori the use of corrective gene therapy. Mechanistically, the experiments of photoreceptor precursor transplantation reveal the importance of cytoplasmic material exchange between the grafted cells and the host cells for functional rescue, an unsuspected mechanism and novel concept. For transplantation of retinal pigmented epithelial cells, the mechanisms behind the therapeutic benefit are only partially understood, and clinical trials are ongoing. The fascinating studies that describe the development of methodologies to produce cells to be grafted and demonstrate the functional benefit for vision are reviewed.
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Affiliation(s)
- Thierry Léveillard
- Department of Genetics, Sorbonne Université, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, F-75012 Paris, France.
| | - Laurence Klipfel
- Department of Genetics, Sorbonne Université, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, F-75012 Paris, France.
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16
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Nickerson PEB, Ortin-Martinez A, Wallace VA. Material Exchange in Photoreceptor Transplantation: Updating Our Understanding of Donor/Host Communication and the Future of Cell Engraftment Science. Front Neural Circuits 2018; 12:17. [PMID: 29559897 PMCID: PMC5845679 DOI: 10.3389/fncir.2018.00017] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 02/09/2018] [Indexed: 12/23/2022] Open
Abstract
Considerable research effort has been invested into the transplantation of mammalian photoreceptors into healthy and degenerating mouse eyes. Several platforms of rod and cone fluorescent reporting have been central to refining the isolation, purification and transplantation of photoreceptors. The tracking of engrafted cells, including identifying the position, morphology and degree of donor cell integration post-transplant is highly dependent on the use of fluorescent protein reporters. Improvements in imaging and analysis of transplant recipients have revealed that donor cell fluorescent reporters can transfer into host tissue though a process termed material exchange (ME). This recent discovery has chaperoned a new era of interpretation when reviewing the field’s use of dissociated donor cell preparations, and has prompted scientists to re-examine how we use and interpret the information derived from fluorescence-based tracking tools. In this review, we describe the status of our understanding of ME in photoreceptor transplantation. In addition, we discuss the impact of this discovery on several aspects of historical rod and cone transplantation data, and provide insight into future standards and approaches to advance the field of cell engraftment.
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Affiliation(s)
- Philip E B Nickerson
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, Toronto, ON, Canada
| | - Arturo Ortin-Martinez
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, Toronto, ON, Canada
| | - Valerie A Wallace
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, Toronto, ON, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada.,Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON, Canada
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