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de Jongh D, Massey EK, Cronin AJ, Schermer MHN, Bunnik EM. Early-Phase Clinical Trials of Bio-Artificial Organ Technology: A Systematic Review of Ethical Issues. Transpl Int 2022; 35:10751. [PMID: 36388425 PMCID: PMC9659568 DOI: 10.3389/ti.2022.10751] [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: 07/08/2022] [Accepted: 10/07/2022] [Indexed: 01/25/2023]
Abstract
Regenerative medicine has emerged as a novel alternative solution to organ failure which circumvents the issue of organ shortage. In preclinical research settings bio-artificial organs are being developed. It is anticipated that eventually it will be possible to launch first-in-human transplantation trials to test safety and efficacy in human recipients. In early-phase transplantation trials, however, research participants could be exposed to serious risks, such as toxicity, infections and tumorigenesis. So far, there is no ethical guidance for the safe and responsible design and conduct of early-phase clinical trials of bio-artificial organs. Therefore, research ethics review committees will need to look to related adjacent fields of research, including for example cell-based therapy, for guidance. In this systematic review, we examined the literature on early-phase clinical trials in these adjacent fields and undertook a thematic analysis of relevant ethical points to consider for early-phase clinical trials of transplantable bio-artificial organs. Six themes were identified: cell source, risk-benefit assessment, patient selection, trial design, informed consent, and oversight and accountability. Further empirical research is needed to provide insight in patient perspectives, as this may serve as valuable input in determining the conditions for ethically responsible and acceptable early clinical development of bio-artificial organs.
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Affiliation(s)
- Dide de Jongh
- Department of Nephrology and Transplantation, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands,Department of Medical Ethics, Philosophy and History of Medicine, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands,*Correspondence: Dide de Jongh,
| | - Emma K. Massey
- Department of Nephrology and Transplantation, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands
| | - Antonia J. Cronin
- Guy’s and St. Thomas’ NHS Foundation Trust, London, United Kingdom,King’s College, London, United Kingdom
| | - Maartje H. N. Schermer
- Department of Medical Ethics, Philosophy and History of Medicine, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands
| | - Eline M. Bunnik
- Department of Medical Ethics, Philosophy and History of Medicine, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands
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2
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Levin LA, Patrick C, Choudry NB, Sharif NA, Goldberg JL. Neuroprotection in neurodegenerations of the brain and eye: Lessons from the past and directions for the future. Front Neurol 2022; 13:964197. [PMID: 36034312 PMCID: PMC9412944 DOI: 10.3389/fneur.2022.964197] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 07/20/2022] [Indexed: 12/24/2022] Open
Abstract
BackgroundNeurological and ophthalmological neurodegenerative diseases in large part share underlying biology and pathophysiology. Despite extensive preclinical research on neuroprotection that in many cases bridges and unifies both fields, only a handful of neuroprotective therapies have succeeded clinically in either.Main bodyUnderstanding the commonalities among brain and neuroretinal neurodegenerations can help develop innovative ways to improve translational success in neuroprotection research and emerging therapies. To do this, analysis of why translational research in neuroprotection fails necessitates addressing roadblocks at basic research and clinical trial levels. These include optimizing translational approaches with respect to biomarkers, therapeutic targets, treatments, animal models, and regulatory pathways.ConclusionThe common features of neurological and ophthalmological neurodegenerations are useful for outlining a path forward that should increase the likelihood of translational success in neuroprotective therapies.
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Affiliation(s)
- Leonard A. Levin
- Departments of Ophthalmology and Visual Sciences, Neurology & Neurosurgery, McGill University, Montreal, QC, Canada
- *Correspondence: Leonard A. Levin
| | | | - Nozhat B. Choudry
- Global Alliances and External Research, Ophthalmology Innovation Center, Santen Inc., Emeryville, CA, United States
| | - Najam A. Sharif
- Global Alliances and External Research, Ophthalmology Innovation Center, Santen Inc., Emeryville, CA, United States
| | - Jeffrey L. Goldberg
- Spencer Center for Vision Research, Byers Eye Institute, Stanford University, Palo Alto, CA, United States
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Microfluidic and Microscale Assays to Examine Regenerative Strategies in the Neuro Retina. MICROMACHINES 2020; 11:mi11121089. [PMID: 33316971 PMCID: PMC7763644 DOI: 10.3390/mi11121089] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/03/2020] [Accepted: 12/05/2020] [Indexed: 12/15/2022]
Abstract
Bioengineering systems have transformed scientific knowledge of cellular behaviors in the nervous system (NS) and pioneered innovative, regenerative therapies to treat adult neural disorders. Microscale systems with characteristic lengths of single to hundreds of microns have examined the development and specialized behaviors of numerous neuromuscular and neurosensory components of the NS. The visual system is comprised of the eye sensory organ and its connecting pathways to the visual cortex. Significant vision loss arises from dysfunction in the retina, the photosensitive tissue at the eye posterior that achieves phototransduction of light to form images in the brain. Retinal regenerative medicine has embraced microfluidic technologies to manipulate stem-like cells for transplantation therapies, where de/differentiated cells are introduced within adult tissue to replace dysfunctional or damaged neurons. Microfluidic systems coupled with stem cell biology and biomaterials have produced exciting advances to restore vision. The current article reviews contemporary microfluidic technologies and microfluidics-enhanced bioassays, developed to interrogate cellular responses to adult retinal cues. The focus is on applications of microfluidics and microscale assays within mammalian sensory retina, or neuro retina, comprised of five types of retinal neurons (photoreceptors, horizontal, bipolar, amacrine, retinal ganglion) and one neuroglia (Müller), but excludes the non-sensory, retinal pigmented epithelium.
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Singh MS, Park SS, Albini TA, Canto-Soler MV, Klassen H, MacLaren RE, Takahashi M, Nagiel A, Schwartz SD, Bharti K. Retinal stem cell transplantation: Balancing safety and potential. Prog Retin Eye Res 2020; 75:100779. [PMID: 31494256 PMCID: PMC7056514 DOI: 10.1016/j.preteyeres.2019.100779] [Citation(s) in RCA: 124] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 08/29/2019] [Accepted: 09/02/2019] [Indexed: 12/14/2022]
Abstract
Stem cell transplantation holds great promise as a potential treatment for currently incurable retinal degenerative diseases that cause poor vision and blindness. Recently, safety data have emerged from several Phase I/II clinical trials of retinal stem cell transplantation. These clinical trials, usually run in partnership with academic institutions, are based on sound preclinical studies and are focused on patient safety. However, reports of serious adverse events arising from cell therapy in other poorly regulated centers have now emerged in the lay and scientific press. While progress in stem cell research for blindness has been greeted with great enthusiasm by patients, scientists, doctors and industry alike, these adverse events have raised concerns about the safety of retinal stem cell transplantation and whether patients are truly protected from undue harm. The aim of this review is to summarize and appraise the safety of human retinal stem cell transplantation in the context of its potential to be developed into an effective treatment for retinal degenerative diseases.
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Affiliation(s)
- Mandeep S Singh
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA.
| | - Susanna S Park
- Department of Ophthalmology & Vision Science, University of California-Davis Eye Center, Sacramento, CA, 95817, USA
| | - Thomas A Albini
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - M Valeria Canto-Soler
- CellSight Ocular Stem Cell and Regeneration Research Program, Department of Ophthalmology, Sue Anschutz-Rodgers Eye Center, University of Colorado School of Medicine, Aurora, CO, 80045, USA
| | - Henry Klassen
- Gavin Herbert Eye Institute and Stem Cell Research Center, Irvine, CA, 92697, USA
| | - Robert E MacLaren
- Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford and Oxford University Eye Hospital, NHS Foundation Trust, NIHR Biomedical Research Centre, Oxford, OX3 9DU, UK
| | - Masayo Takahashi
- Laboratory for Retinal Regeneration, Center for Biosystems Dynamics Research, RIKEN, Kobe, Hyogo, 650-0047, Japan
| | - Aaron Nagiel
- The Vision Center, Department of Surgery, Children's Hospital Los Angeles, Los Angeles, CA, 90027, USA; USC Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90007, USA
| | - Steven D Schwartz
- Stein Eye Institute, University of California Los Angeles Geffen School of Medicine, Los Angeles, CA, 90095, USA; Edythe and Eli Broad Stem Cell Institute, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Kapil Bharti
- National Eye Institute, National Institutes of Health, Bethesda, MD, 90892, USA
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Laird JG, Gardner SH, Kopel AJ, Kerov V, Lee A, Baker SA. Rescue of Rod Synapses by Induction of Cav Alpha 1F in the Mature Cav1.4 Knock-Out Mouse Retina. Invest Ophthalmol Vis Sci 2019; 60:3150-3161. [PMID: 31335952 PMCID: PMC6656410 DOI: 10.1167/iovs.19-27226] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 06/24/2019] [Indexed: 01/10/2023] Open
Abstract
Purpose Cav1.4 is a voltage-gated calcium channel clustered at the presynaptic active zones of photoreceptors. Cav1.4 functions in communication by mediating the Ca2+ influx that triggers neurotransmitter release. It also aids in development since rod ribbon synapses do not form in Cav1.4 knock-out mice. Here we used a rescue strategy to investigate the ability of Cav1.4 to trigger synaptogenesis in both immature and mature mouse rods. Methods In vivo electroporation was used to transiently express Cav α1F or tamoxifen-inducible Cav α1F in a subset of Cav1.4 knock-out mouse rods. Synaptogenesis was assayed using morphologic markers and a vision-guided water maze. Results We found that introduction of Cav α1F to knock-out terminals rescued synaptic development as indicated by PSD-95 expression and elongated ribbons. When expression of Cav α1F was induced in mature animals, we again found restoration of PSD-95 and elongated ribbons. However, the induced expression of Cav α1F led to diffuse distribution of Cav α1F in the terminal instead of being clustered beneath the ribbon. Approximately a quarter of treated animals passed the water maze test, suggesting the rescue of retinal signaling in these mice. Conclusions These data confirm that Cav α1F expression is necessary for rod synaptic terminal development and demonstrate that rescue is robust even in adult animals with late stages of synaptic disease. The degree of rod synaptic plasticity seen here should be sufficient to support future vision-restoring treatments such as gene or cell replacement that will require photoreceptor synaptic rewiring.
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Affiliation(s)
- Joseph G. Laird
- Department of Biochemistry, University of Iowa, Iowa City, United States
| | - Sarah H. Gardner
- Department of Biochemistry, University of Iowa, Iowa City, United States
| | - Ariel J. Kopel
- Department of Biochemistry, University of Iowa, Iowa City, United States
| | - Vasily Kerov
- Molecular Physiology and Biophysics, University of Iowa, Iowa City, United States
| | - Amy Lee
- Molecular Physiology and Biophysics, University of Iowa, Iowa City, United States
- Otolaryngology-Head and Neck Surgery, University of Iowa, Iowa City, United States
- Department of Neurology, University of Iowa, Iowa City, United States
- Iowa Neuroscience Institute, University of Iowa, Iowa City, United States
| | - Sheila A. Baker
- Department of Biochemistry, University of Iowa, Iowa City, United States
- Iowa Neuroscience Institute, University of Iowa, Iowa City, United States
- Ophthalmology and Visual Sciences and the Institute for Vision Research, University of Iowa, Iowa City, United States
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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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Couroucli XI. Oxidative stress in the retina: implications for Retinopathy of Prematurity. CURRENT OPINION IN TOXICOLOGY 2018; 7:102-109. [PMID: 35784947 DOI: 10.1016/j.cotox.2017.11.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Oxygen supplementation has been used as a part of respiratory care for preterm and term newborns since the beginning of 19th century. Although oxygen administration can be life-saving, reactive oxygen species (ROS) and reactive nitrogen species (RNS) due to hyperoxia can have detrimental effects in the developing organs of the preterm infants, with both short and long term consequences. Oxygen toxicity on the immature tissues of preterm infants can contribute to the development of several diseases like retinopathy of prematurity (ROP) and bronchopulmonary dysplasia (BPD). The vascular development of human retina is completed at term, whereas the neural retina develops up to 5 years of age. Disruption of the normal retinal neurovascular growth is the pathognomonic feature of ROP, and can lead to vision threatening disease or even blindness. It is estimated that at least 100,000 infants all over the world will be blind every year due to ROP, which is the leading cause of blindness in children. In this review we will discuss the role of ROS and RNS in the development of ROP, and how through historical, epidemiological, and developmental aspects of this devastating disease, we can design future research for its prevention and treatment.
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Affiliation(s)
- Xanthi I Couroucli
- Section of Neonatology, Department of Pediatrics, Baylor College of Medicine and Texas Children's Hospital, 1102 Bates Avenue, Suite 530, Houston, Texas 77030. U.S.A
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Au ED, Fernandez-Godino R, Kaczynksi TJ, Sousa ME, Farkas MH. Characterization of lincRNA expression in the human retinal pigment epithelium and differentiated induced pluripotent stem cells. PLoS One 2017; 12:e0183939. [PMID: 28837677 PMCID: PMC5570510 DOI: 10.1371/journal.pone.0183939] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 08/14/2017] [Indexed: 11/29/2022] Open
Abstract
Long intervening non-coding RNAs (lincRNAs) are increasingly being implicated as important factors in many aspects of cellular development, function, and disease, but remain poorly understood. In this study, we examine the human retinal pigment epithelium (RPE) lincRNA transcriptome using RNA-Seq data generated from human fetal RPE (fRPE), RPE derived from human induced pluripotent stem cells (iPS-RPE), and undifferentiated iPS (iPS). In addition, we determine the suitability of iPS-RPE, from a transcriptome standpoint, as a model for use in future studies of lincRNA structure and function. A comparison of gene and isoform expression across the whole transcriptome shows only minimal differences between all sample types, though fRPE and iPS-RPE show higher concordance than either shows with iPS. Notably, RPE signature genes show the highest degree of fRPE to iPS-RPE concordance, indicating that iPS-RPE cells provide a suitable model for use in future studies. An analysis of lincRNAs demonstrates high concordance between fRPE and iPS-RPE, but low concordance between either RPE and iPS. While most lincRNAs are expressed at low levels (RPKM < 10), there is a high degree of concordance among replicates within each sample type, suggesting the expression is consistent, even at levels subject to high variability. Finally, we identified and annotated 180 putative novel genes in the fRPE samples, a majority of which are also expressed in the iPS-RPE. Overall, this study represents the first characterization of lincRNA expression in the human RPE, and provides a model for studying the role lincRNAs play in RPE development, function, and disease.
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Affiliation(s)
- Elizabeth D. Au
- Department of Ophthalmology, Jacobs School of Medicine and Biomedical Science, State University of New York at Buffalo, Buffalo, NY, United States of America
| | - Rosario Fernandez-Godino
- Ocular Genomics Institute, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, United States of America
| | - Tadeusz J. Kaczynksi
- Department of Ophthalmology, Jacobs School of Medicine and Biomedical Science, State University of New York at Buffalo, Buffalo, NY, United States of America
- Research Service, Veterans Administration Western New York Healthcare System, Buffalo, NY, United States of America
| | - Maria E. Sousa
- Department of Ophthalmology, Jacobs School of Medicine and Biomedical Science, State University of New York at Buffalo, Buffalo, NY, United States of America
- Research Service, Veterans Administration Western New York Healthcare System, Buffalo, NY, United States of America
| | - Michael H. Farkas
- Department of Ophthalmology, Jacobs School of Medicine and Biomedical Science, State University of New York at Buffalo, Buffalo, NY, United States of America
- Research Service, Veterans Administration Western New York Healthcare System, Buffalo, NY, United States of America
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Science, State University of New York at Buffalo, Buffalo, NY, United States of America
- * E-mail:
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