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Lee JS, Lee SY, Chin HS, Kim NR, Jung JW. Microstructure of the corneal endothelial transition zone in different laboratory animals. Mol Vis 2024; 30:107-113. [PMID: 38601017 PMCID: PMC11006004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 03/15/2024] [Indexed: 04/12/2024] Open
Abstract
Purpose To compare the microstructure of the corneal endothelial transition zone in different laboratory animals. Methods Flat-mount corneas of rabbits, rats, and mice were stained with Alizarin Red S (ARS) and observed using scanning electron microscopy (SEM). The progenitor cell markers p75 neurotrophin receptor (p75NTR), SRY-box transcription factor 9 (SOX9), leucine-rich repeat-containing G protein-coupled receptor 5 (Lgr5), telomerase reverse transcriptase (TERT), and proliferation marker Ki-67 were examined in the flat-mounted corneas of three laboratory animals using immunofluorescence microscopy. Results On flat mounts, proximity to the trabecular meshwork correlated with weaker ARS staining and greater polymorphism of endothelial cells in the transition zone in all animals. On SEM, distinct and smooth structures of the transition zone were negligibly detected in all animals. The endothelial cells in the transition zone had irregular shapes, with less dense, less wavy intercellular junctions, especially in murine corneas, exhibiting unique intercellular cystic spaces. In the transition zone of the rabbit cornea, progenitor cell markers p75NTR, SOX9, Lgr5, TERT, and proliferation marker Ki-67 were expressed, in contrast to those in other murine corneas. Conclusions Although the transition zone was not identified clearly, irregular cell morphology and loss of cell-cell contact were observed in all animal corneal endothelial cells. The proliferative capacity and the presence of progenitor cells were confirmed in the transition zone, especially in the rabbit cornea.
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Affiliation(s)
- Jun Seob Lee
- Department of Ophthalmology and Inha Vision Science Laboratory, Inha University School of Medicine, Incheon, South Korea
| | - So Young Lee
- Department of Ophthalmology and Inha Vision Science Laboratory, Inha University School of Medicine, Incheon, South Korea
| | - Hee Seung Chin
- Department of Ophthalmology and Inha Vision Science Laboratory, Inha University School of Medicine, Incheon, South Korea
| | - Na Rae Kim
- Department of Ophthalmology and Inha Vision Science Laboratory, Inha University School of Medicine, Incheon, South Korea
| | - Ji Won Jung
- Department of Ophthalmology and Inha Vision Science Laboratory, Inha University School of Medicine, Incheon, South Korea
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Saranya P, Shekhar M, Haripriya A, Muthukkaruppan V, Gowri Priya C. Towards the Identification and Characterization of Putative Adult Human Lens Epithelial Stem Cells. Cells 2023; 12:2727. [PMID: 38067155 PMCID: PMC10706574 DOI: 10.3390/cells12232727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 11/20/2023] [Accepted: 11/22/2023] [Indexed: 12/18/2023] Open
Abstract
The anterior lens epithelium has the ability to differentiate into lens fibres throughout its life. The present study aims to identify and functionally characterize the adult stem cells in the human lens epithelium. Whole mounts of lens epithelium from donor eyes (normal/cataract) were immunostained for SOX2, gap junction protein alpha 1 (GJA1), PAX6, α, β and γ-crystallins, followed by a confocal analysis. The functional property of adult stem cells was analysed by their sphere forming ability using cultured lens epithelial cells from different zones. Based on marker expression, the lens epithelium was divided into four zones: the central zone, characterized by a small population of PAX6+, GJA1-, β-crystallin- and γ-crystallin- cells; the germinative zone, characterized by PAX6+, GJA1+, β-crystallin- and γ-crystallin-; the transitional zone, characterized by PAX6+, GJA1+, β-crystallin+ and γ-crystallin-; and the equatorial zone, characterized by PAX6+/-, GJA1+, β-crystallin+, and γ-crystallin+ cells. The putative lens epithelial stem cells identified as SOX2+ and GJA1 membrane expression negative cells were located only in the central zone (1.89 ± 0.84%). Compared to the other zones, a significant percentage of spheres were identified in the central zone (1.68 ± 1.04%), consistent with the location of the putative adult lens epithelial stem cells. In the cataractous lens, an absence of SOX2 expression and a significant reduction in sphere forming ability (0.33 ± 0.11%) were observed in the central zone. The above findings confirmed the presence of putative stem cells in the central zone of the adult human lens epithelium and indicated their probable association with cataract development.
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Affiliation(s)
- Pandi Saranya
- Department of Immunology and Stem Cell Biology, Aravind Medical Research Foundation, Madurai 625020, India; (P.S.); (V.M.)
- Department of Biotechnology, Aravind Medical Research Foundation—Affiliated to Alagappa University, Karaikudi 630003, India
| | - Madhu Shekhar
- Cataract and IOL Services, Aravind Eye Hospital and Post Graduate Institute of Ophthalmology, Madurai 625020, India;
| | - Aravind Haripriya
- Intraocular Lens and Cataract Services, Aravind Eye Hospital, Chennai 600077, India;
| | - Veerappan Muthukkaruppan
- Department of Immunology and Stem Cell Biology, Aravind Medical Research Foundation, Madurai 625020, India; (P.S.); (V.M.)
| | - Chidambaranathan Gowri Priya
- Department of Immunology and Stem Cell Biology, Aravind Medical Research Foundation, Madurai 625020, India; (P.S.); (V.M.)
- Department of Biotechnology, Aravind Medical Research Foundation—Affiliated to Alagappa University, Karaikudi 630003, India
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Yam GHF, Pi S, Du Y, Mehta JS. Posterior corneoscleral limbus: Architecture, stem cells, and clinical implications. Prog Retin Eye Res 2023; 96:101192. [PMID: 37392960 DOI: 10.1016/j.preteyeres.2023.101192] [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: 04/19/2023] [Revised: 06/22/2023] [Accepted: 06/23/2023] [Indexed: 07/03/2023]
Abstract
The limbus is a transition from the cornea to conjunctiva and sclera. In human eyes, this thin strip has a rich variation of tissue structures and composition, typifying a change from scleral irregularity and opacity to corneal regularity and transparency; a variation from richly vascularized conjunctiva and sclera to avascular cornea; the neural passage and drainage of aqueous humor. The limbal stroma is enriched with circular fibres running parallel to the corneal circumference, giving its unique role in absorbing small pressure changes to maintain corneal curvature and refractivity. It contains specific niches housing different types of stem cells for the corneal epithelium, stromal keratocytes, corneal endothelium, and trabecular meshwork. This truly reflects the important roles of the limbus in ocular physiology, and the limbal functionality is crucial for corneal health and the entire visual system. Since the anterior limbus containing epithelial structures and limbal epithelial stem cells has been extensively reviewed, this article is focused on the posterior limbus. We have discussed the structural organization and cellular components of the region beneath the limbal epithelium, the characteristics of stem cell types: namely corneal stromal stem cells, endothelial progenitors and trabecular meshwork stem cells, and recent advances leading to the emergence of potential cell therapy options to replenish their respective mature cell types and to correct defects causing corneal abnormalities. We have reviewed different clinical disorders associated with defects of the posterior limbus and summarized the available preclinical and clinical evidence about the developing topic of cell-based therapy for corneal disorders.
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Affiliation(s)
- Gary Hin-Fai Yam
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA; Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore; McGowan Institute for Regenerative Medicine, Pittsburgh, PA, USA.
| | - Shaohua Pi
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Yiqin Du
- Department of Ophthalmology, University of South Florida, Tampa, FL, USA
| | - Jodhbir S Mehta
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore; Department of Cornea and External Eye Disease, Singapore National Eye Centre, Singapore; Ophthalmology and Visual Sciences Academic Clinical Program, Duke-National University of Singapore (NUS) Medical School, Singapore.
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Kopecny LR, Lee BWH, Coroneo MT. A systematic review on the effects of ROCK inhibitors on proliferation and/or differentiation in human somatic stem cells: A hypothesis that ROCK inhibitors support corneal endothelial healing via acting on the limbal stem cell niche. Ocul Surf 2023; 27:16-29. [PMID: 36586668 DOI: 10.1016/j.jtos.2022.12.008] [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: 10/09/2022] [Revised: 12/18/2022] [Accepted: 12/22/2022] [Indexed: 12/29/2022]
Abstract
Rho kinase inhibitors (ROCKi) have attracted growing multidisciplinary interest, particularly in Ophthalmology where the question as to how they promote corneal endothelial healing remains unresolved. Concurrently, stem cell biology has rapidly progressed in unravelling drivers of stem cell (SC) proliferation and differentiation, where mechanical niche factors and the actin cytoskeleton are increasingly recognized as key players. There is mounting evidence from the study of the peripheral corneal endothelium that supports the likelihood of an internal limbal stem cell niche. The possibility that ROCKi stimulate the endothelial SC niche has not been addressed. Furthermore, there is currently a paucity of data that directly evaluates whether ROCKi promotes corneal endothelial healing by acting on this limbal SC niche located near the transition zone. Therefore, we performed a systematic review examining the effects ROCKi on the proliferation and differentiation of human somatic SC, to provide insight into its effects on various human SC populations. An appraisal of electronic searches of four databases identified 1 in vivo and 58 in vitro studies (36 evaluated proliferation while 53 examined differentiation). Types of SC studied included mesenchymal (n = 32), epithelial (n = 11), epidermal (n = 8), hematopoietic and other (n = 8). The ROCK 1/2 selective inhibitor Y-27632 was used in almost all studies (n = 58), while several studies evaluated ≥2 ROCKi (n = 4) including fasudil, H-1152, and KD025. ROCKi significantly influenced human somatic SC proliferation in 81% of studies (29/36) and SC differentiation in 94% of studies (50/53). The present systemic review highlights that ROCKi are influential in regulating human SC proliferation and differentiation, and provides evidence to support the hypothesis that ROCKi promotes corneal endothelial division and maintenance via acting on the inner limbal SC niche.
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Affiliation(s)
- Lloyd R Kopecny
- School of Clinical Medicine, University of New South Wales, Sydney, Australia.
| | - Brendon W H Lee
- Department of Ophthalmology, School of Clinical Medicine, University of New South Wales, Level 2 South Wing, Edmund Blacket Building, Prince of Wales Hospital, Randwick, NSW, 2031, Australia
| | - Minas T Coroneo
- Department of Ophthalmology, Prince of Wales Hospital, Sydney, Australia
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Hazra S, Sneha IV, Chaurasia S, Ramachandran C. In Vitro Expansion of Corneal Endothelial Cells for Clinical Application: Current Update. Cornea 2022; 41:1313-1324. [PMID: 36107851 DOI: 10.1097/ico.0000000000003080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Accepted: 05/08/2022] [Indexed: 11/25/2022]
Abstract
ABSTRACT Endothelial dysfunction is one of the leading causes of corneal blindness and one of the common indications for keratoplasty. At present, the standard of treatment involves the replacement of the dysfunctional endothelium with healthy tissue taken from a donor. Because there is a paucity of healthy donor tissues, research on the corneal endothelium has focused primarily on expanding these cells in the laboratory for transplantation in an attempt to reduce the gap between the demand and supply of donor tissues for transplantation. To expand these cells, which are nonmitotic in vivo, various mitogens, substrates, culture systems, and alternate strategies have been tested with varying success. The biggest challenge has been the limited proliferative capacity of these cells compounded with endothelial to mesenchymal transition that alters the functioning of these cells and renders them unsuitable for human transplantation. This review aims to give a comprehensive overview of the most common and successful techniques used in the culture of the cells, the current available evidence in support of epithelial to mesenchymal transition (EMT), alternate sources for deriving the corneal endothelial cells, and advances made in transplantation of these cells.
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Affiliation(s)
- Swatilekha Hazra
- Prof. Brien Holden Eye Research Centre, LV Prasad Eye Institute, Hyderabad, India
- Manipal University, Manipal, Karnataka, India ; and
| | - Iskala V Sneha
- Prof. Brien Holden Eye Research Centre, LV Prasad Eye Institute, Hyderabad, India
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Sundaresan Y, Manivannan LP, Radhakrishnan S, Ramasamy KS, Veerappan M, Chidambaranathan GP. Reduction in trabecular meshwork stem cell content in donor eyes with primary open angle glaucoma. Sci Rep 2021; 11:24518. [PMID: 34972817 PMCID: PMC8720087 DOI: 10.1038/s41598-021-03345-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 11/25/2021] [Indexed: 11/30/2022] Open
Abstract
We previously identified and characterized human trabecular meshwork stem cells (TMSCs) based on high expression of ABCG2/p75 positivity and high nucleus to cytoplasmic ratio. These TMSCs expressing high ABCG2 and p75 were located to the insert region of the human TM. Additionally, we demonstrated an age-related reduction in the TMSC content which was significantly associated with TM cell loss. In continuation, this study was aimed to determine the TMSC content in glaucomatous donor eyes wherein a drastic reduction in TM cellularity has already been reported. Anterior segments from known glaucomatous (n = 6) and age-matched normal (n = 8) donors were dissected into four quadrants. A minimum of three sections from each quadrant were used for histopathological analysis as well as immunostaining. Analysis of hematoxylin and eosin-stained sections from glaucomatous tissues revealed a decrease in total TM cellularity, thickening of trabecular beams, fusion of trabeculae, absence of patent Schlemm's canal compared to age-matched controls. In addition, the TM thickness at various positions of the meshwork and the coronal as well as the meridional diameters of the Schlemm's canal were observed to be significantly reduced in glaucomatous eyes. Further, sections from both the groups were immunostained for universal stem cell marker ABCG2 and neural crest derived stem cell marker p75. The images were acquired using Leica SP8 confocal microscope. Quantification of total TM cellularity based on nuclear counterstain (mean ± SD) using ImageJ identified 69.33 ± 12.77 cells/section in control eyes. In glaucomatous donors, the TM cellularity was found to be reduced significantly to 41.83 ± 9.0 (p = 0.0007). In addition, a reduction in the percentage of TMSCs (cells with high ABCG2 expression and p75 positivity) was evident in glaucomatous donors (0.14 ± 0.17%) compared to age-matched controls (4.73 ± 5.46%) (p = 0.064). Thus, the present study confirmed the significant decline in TM cellularity and a reducing trend in the TMSC content, though this reduction was non-significant in glaucomatous donor eyes. Further studies are essential to elucidate the role of TMSCs in the pathogenesis of primary open angle glaucoma.
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Affiliation(s)
- Yogapriya Sundaresan
- grid.413854.f0000 0004 1767 7755Department of Immunology and Stem Cell Biology, Aravind Medical Research Foundation, Madurai, 625020 Tamil Nadu India
| | - Lakshmi Priya Manivannan
- grid.413854.f0000 0004 1767 7755Department of Immunology and Stem Cell Biology, Aravind Medical Research Foundation, Madurai, 625020 Tamil Nadu India
| | - Shanthi Radhakrishnan
- grid.413854.f0000 0004 1767 7755Department of Pathology, Aravind Eye Hospital and Post Graduate Institute of Ophthalmology, Madurai, 625020 Tamil Nadu India
| | - Krishnadas Subbiah Ramasamy
- grid.413854.f0000 0004 1767 7755Glaucoma Clinic, Aravind Eye Hospital and Post Graduate Institute of Ophthalmology, Madurai, 625020 Tamil Nadu India
| | - Muthukkaruppan Veerappan
- grid.413854.f0000 0004 1767 7755Department of Immunology and Stem Cell Biology, Aravind Medical Research Foundation, Madurai, 625020 Tamil Nadu India
| | - Gowri Priya Chidambaranathan
- Department of Immunology and Stem Cell Biology, Aravind Medical Research Foundation, Madurai, 625020, Tamil Nadu, India.
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Hidalgo-Alvarez V, Dhowre HS, Kingston OA, Sheridan CM, Levis HJ. Biofabrication of Artificial Stem Cell Niches in the Anterior Ocular Segment. Bioengineering (Basel) 2021; 8:135. [PMID: 34677208 PMCID: PMC8533470 DOI: 10.3390/bioengineering8100135] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/27/2021] [Accepted: 09/27/2021] [Indexed: 11/16/2022] Open
Abstract
The anterior segment of the eye is a complex set of structures that collectively act to maintain the integrity of the globe and direct light towards the posteriorly located retina. The eye is exposed to numerous physical and environmental insults such as infection, UV radiation, physical or chemical injuries. Loss of transparency to the cornea or lens (cataract) and dysfunctional regulation of intra ocular pressure (glaucoma) are leading causes of worldwide blindness. Whilst traditional therapeutic approaches can improve vision, their effect often fails to control the multiple pathological events that lead to long-term vision loss. Regenerative medicine approaches in the eye have already had success with ocular stem cell therapy and ex vivo production of cornea and conjunctival tissue for transplant recovering patients' vision. However, advancements are required to increase the efficacy of these as well as develop other ocular cell therapies. One of the most important challenges that determines the success of regenerative approaches is the preservation of the stem cell properties during expansion culture in vitro. To achieve this, the environment must provide the physical, chemical and biological factors that ensure the maintenance of their undifferentiated state, as well as their proliferative capacity. This is likely to be accomplished by replicating the natural stem cell niche in vitro. Due to the complex nature of the cell microenvironment, the creation of such artificial niches requires the use of bioengineering techniques which can replicate the physico-chemical properties and the dynamic cell-extracellular matrix interactions that maintain the stem cell phenotype. This review discusses the progress made in the replication of stem cell niches from the anterior ocular segment by using bioengineering approaches and their therapeutic implications.
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Affiliation(s)
- Veronica Hidalgo-Alvarez
- Institute of Biological Chemistry, Biophysics and Bioengineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, UK
| | - Hala S. Dhowre
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L7 8TX, UK; (H.S.D.); (O.A.K.)
| | - Olivia A. Kingston
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L7 8TX, UK; (H.S.D.); (O.A.K.)
| | - Carl M. Sheridan
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L7 8TX, UK; (H.S.D.); (O.A.K.)
| | - Hannah J. Levis
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L7 8TX, UK; (H.S.D.); (O.A.K.)
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Fan X, Bilir EK, Kingston OA, Oldershaw RA, Kearns VR, Willoughby CE, Sheridan CM. Replacement of the Trabecular Meshwork Cells-A Way Ahead in IOP Control? Biomolecules 2021; 11:biom11091371. [PMID: 34572584 PMCID: PMC8464777 DOI: 10.3390/biom11091371] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/09/2021] [Accepted: 09/13/2021] [Indexed: 12/11/2022] Open
Abstract
Glaucoma is one of the leading causes of vision loss worldwide, characterised with irreversible optic nerve damage and progressive vision loss. Primary open-angle glaucoma (POAG) is a subset of glaucoma, characterised by normal anterior chamber angle and raised intraocular pressure (IOP). Reducing IOP is the main modifiable factor in the treatment of POAG, and the trabecular meshwork (TM) is the primary site of aqueous humour outflow (AH) and the resistance to outflow. The structure and the composition of the TM are key to its function in regulating AH outflow. Dysfunction and loss of the TM cells found in the natural ageing process and more so in POAG can cause abnormal extracellular matrix (ECM) accumulation, increased TM stiffness, and increased IOP. Therefore, repair or regeneration of TM's structure and function is considered as a potential treatment for POAG. Cell transplantation is an attractive option to repopulate the TM cells in POAG, but to develop a cell replacement approach, various challenges are still to be addressed. The choice of cell replacement covers autologous or allogenic approaches, which led to investigations into TM progenitor cells, induced pluripotent stem cells (iPSCs), and mesenchymal stem cells (MSCs) as potential stem cell source candidates. However, the potential plasticity and the lack of definitive cell markers for the progenitor and the TM cell population compound the biological challenge. Morphological and differential gene expression of TM cells located within different regions of the TM may give rise to different cell replacement or regenerative approaches. As such, this review describes the different approaches taken to date investigating different cell sources and their differing cell isolation and differentiation methodologies. In addition, we highlighted how these approaches were evaluated in different animal and ex vivo model systems and the potential of these methods in future POAG treatment.
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Affiliation(s)
- Xiaochen Fan
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L69 3BX, UK; (X.F.); (E.K.B.); (O.A.K.); (V.R.K.)
| | - Emine K. Bilir
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L69 3BX, UK; (X.F.); (E.K.B.); (O.A.K.); (V.R.K.)
| | - Olivia A. Kingston
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L69 3BX, UK; (X.F.); (E.K.B.); (O.A.K.); (V.R.K.)
| | - Rachel A. Oldershaw
- Department of Musculoskeletal and Ageing Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L69 3BX, UK;
| | - Victoria R. Kearns
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L69 3BX, UK; (X.F.); (E.K.B.); (O.A.K.); (V.R.K.)
| | - Colin E. Willoughby
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L69 3BX, UK; (X.F.); (E.K.B.); (O.A.K.); (V.R.K.)
- Genomic Medicine, Biomedical Sciences Research Institute, Ulster University, Coleraine BT52 1SA, UK
- Correspondence: (C.E.W.); (C.M.S.); Tel.: +44-(28)-701-2338 (C.E.W.); +44-(151)-794-9031 (C.M.S.)
| | - Carl M. Sheridan
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L69 3BX, UK; (X.F.); (E.K.B.); (O.A.K.); (V.R.K.)
- Correspondence: (C.E.W.); (C.M.S.); Tel.: +44-(28)-701-2338 (C.E.W.); +44-(151)-794-9031 (C.M.S.)
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Sundaresan Y, Ramasamy KS, Veerappan M, Chidambaranathan GP. Functional characterization of adult human trabecular meshwork stem cells. Exp Cell Res 2021; 405:112709. [PMID: 34174318 DOI: 10.1016/j.yexcr.2021.112709] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 05/13/2021] [Accepted: 06/21/2021] [Indexed: 10/21/2022]
Abstract
We earlier identified native human trabecular meshwork stem cells (TMSCs) based on two-parameters- high ABCG2 expression and high nucleus to cytoplasmic ratio. The TMSCs also expressed p75 and AnkyrinG. Based on the high expression of ABCG2 and p75, the TMSCs were identified to be located in the Schwalbe's line region of the TM. In continuation, the current study aimed at elucidating the functional characteristics of human TMSCs. Upon culturing, only a small proportion of TM cells (0.96 ± 0.21% in <30 years) expressing stem cell markers ABCG2 and p75 adhered to the culture dish. This proportion significantly reduced with ageing (0.32 ± 0.23% in 30-60 years and 0.35 ± 0.04% in >60 years). Characterization of the primary TM cultures identified 7.00 ± 1.80% of stem cells with label retaining property. Further, cultured cells had the ability to form TM spheres (0.82 ± 0.23%) which consisted of high ABCG2 and p75 positive cells. Upon dexamethasone induction, 86.00 ± 14.87% and 64.60 ± 7.24% of the cells derived from the TM spheres expressed myocilin and exhibited cross linked actin networks respectively, indicating differentiation of the TMSCs in the sphere to TM cells. In addition, the sphere derived TM cells also possessed phagocytic potential (13.28 ± 3.30%) equivalent to primary TM cells (16.33 ± 4.04%) which was evident upon internalization of zymosan particles. In conclusion, this study has established that a proportion of cultured TM cells had the label retaining property as well as sphere forming ability of adult stem cells. Thus, these results confirm the presence of adult stem cells in the human TM that might be responsible for the maintenance of tissue homeostasis.
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Affiliation(s)
- Yogapriya Sundaresan
- Department of Immunology and Stem Cell Biology, Aravind Medical Research Foundation, Madurai, Tamil Nadu, India
| | - Krishnadas Subbiah Ramasamy
- Glaucoma Clinic, Aravind Eye Hospital and Post Graduate Institute of Ophthalmology, Madurai, Tamil Nadu, India
| | - Muthukkaruppan Veerappan
- Department of Immunology and Stem Cell Biology, Aravind Medical Research Foundation, Madurai, Tamil Nadu, India
| | - Gowri Priya Chidambaranathan
- Department of Immunology and Stem Cell Biology, Aravind Medical Research Foundation, Madurai, Tamil Nadu, India.
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Regenerative capacity of the corneal transition zone for endothelial cell therapy. Stem Cell Res Ther 2020; 11:523. [PMID: 33276809 PMCID: PMC7716425 DOI: 10.1186/s13287-020-02046-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Accepted: 11/23/2020] [Indexed: 12/13/2022] Open
Abstract
The corneal endothelium located on the posterior corneal surface is responsible for regulating stromal hydration. This is contributed by a monolayer of corneal endothelial cells (CECs), which are metabolically active in a continuous fluid-coupled efflux of ions from the corneal stroma into the aqueous humor, preventing stromal over-hydration and preserving the orderly arrangement of stromal collagen fibrils, which is essential for corneal transparency. Mature CECs do not have regenerative capacity and cell loss due to aging and diseases results in irreversible stromal edema and a loss of corneal clarity. The current gold standard of treatment for this worldwide blindness caused by corneal endothelial failure is the corneal transplantation using cadaveric donor corneas. The top indication is Fuchs corneal endothelial dystrophy/degeneration, which represents 39% of all corneal transplants performed. However, the global shortage of transplantable donor corneas has restricted the treatment outcomes, hence instigating a need to research for alternative therapies. One such avenue is the CEC regeneration from endothelial progenitors, which have been identified in the peripheral endothelium and the adjacent transition zone. This review examines the evidence supporting the existence of endothelial progenitors in the posterior limbus and summarizes the existing knowledge on the microanatomy of the transitional zone. We give an overview of the isolation and ex vivo propagation of human endothelial progenitors in the transition zone, and their growth and differentiation capacity to the corneal endothelium. Transplanting these bioengineered constructs into in vivo models of corneal endothelial degeneration will prove the efficacy and viability, and the long-term maintenance of functional endothelium. This will develop a novel regenerative therapy for the management of corneal endothelial diseases.
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Li X, Xiao Y, Gao XW, Liu Y, Lei DK. Experimental study of trabecular tissue repair for corneal defect in rabbits. Int J Ophthalmol 2020; 13:1356-1360. [PMID: 32953571 DOI: 10.18240/ijo.2020.09.03] [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: 02/19/2020] [Accepted: 07/02/2020] [Indexed: 11/23/2022] Open
Abstract
AIM To investigate the mechanism and effect of trabecular tissue repair for corneal defect, and to provide a theoretical basis for its clinical application. METHODS Trabeculectomy was performed on 40 (80 eyes) of 70 New Zealand white rabbits. Take trabecular tissue for backup. Thirty (30 eyes) corneal defect models were made, trabecular tissue was filled in the corneal defect, and the oblique cross stitch was used to suture the corneal laceration and debridement. Anterior segment image and optical coherence tomography (OCT) were performed at the time 1d, 1wk, 1 and 3mo after the model was made. After the observation, the cornea was taken and stained with trypanosome blue-alizarin red and the pathological tissue was examined. RESULTS Observation 1wk after surgery, the area of corneal defect was edema, but the corneal curvature was basically normal, and the anterior chamber existed under slit lamp. After 3mo of observation, most corneal defects were repaired in the form of corneal leucoma and corneal macula (73.3%), the filled trabecular tissue gradually became transparent, fused tightly with the corneal tissue, and the corneal curvature was relatively smooth. But in one case, the trabecular planter was partially detached, no serious complications such as corneal laceration occurred after the stitches were removed. CONCLUSION The trabecular tissue structure is similar to the corneal, and it can be used as a substitute for the corneal tissue defect by providing fiber scaffolds and cell amplification differentiation, and lay a foundation for the second-stage surgical treatment.
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Affiliation(s)
- Xia Li
- Ophthalmology Center of the Army, General Hospital of Xinjiang Military Region, Urumchi 830013, Xinjiang Uygur Autonomous Region, China
| | - Yun Xiao
- Ophthalmology Center of the Army, General Hospital of Xinjiang Military Region, Urumchi 830013, Xinjiang Uygur Autonomous Region, China
| | - Xiao-Wei Gao
- Ophthalmology Center of the Army, General Hospital of Xinjiang Military Region, Urumchi 830013, Xinjiang Uygur Autonomous Region, China
| | - Yi Liu
- Ophthalmology Center of the Army, General Hospital of Xinjiang Military Region, Urumchi 830013, Xinjiang Uygur Autonomous Region, China
| | - Dai-Kun Lei
- Ophthalmology Center of the Army, General Hospital of Xinjiang Military Region, Urumchi 830013, Xinjiang Uygur Autonomous Region, China
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Sundaresan Y, Veerappan M, Ramasamy KS, Chidambaranathan GP. Identification, quantification and age-related changes of human trabecular meshwork stem cells. EYE AND VISION 2019; 6:31. [PMID: 31641682 PMCID: PMC6796401 DOI: 10.1186/s40662-019-0156-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 09/21/2019] [Indexed: 01/07/2023]
Abstract
Background Loss of cells in the human trabecular meshwork (TM) has been reported with ageing and in glaucoma. This study aims to identify, quantify and determine the age-related changes of human TM stem cells (TMSCs). Methods Isolation of TM cells/ paraffin sectioning was carried out using human corneoscleral rings and whole globes. The TM cells/ sections were immunostained for the stem cell markers ATP-binding cassette protein G2 (ABCG2), nerve growth factor receptor p75 and AnkyrinG (AnkG). Images were acquired using Leica SP8 confocal microscope. The isolated cells were analyzed for two parameters- ABCG2 expression and nucleus to cytoplasmic ratio (N/C ratio). The total number of TM cells and those positive for ABCG2 and p75 in each section were quantified. Spearman rank order correlation was used to determine the association between age and the cell counts. Results The TMSCs were identified based on two parameters- high ABCG2 expression and high N/C ratio > 0.7. These stem cells were also positive for p75 and AnkG. The TMSC content based on the two parameters was 21.0 ± 1.4% in < 30 years age group, 12.6 ± 6.6% in 30-60 years and 4.0 ± 3.5% in > 60 years. The stem cells with high ABCG2 and p75 expression were restricted to the Schwalbe's line region of the TM. A significant correlation was observed between the reduction in TMSC content and TM cell count during ageing. Conclusion The human TMSCs were identified and quantified based on two parameter analysis. This study established a significant association between age-related reduction in TMSC content and TM cell loss.
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Affiliation(s)
- Yogapriya Sundaresan
- 1Department of Immunology and Stem Cell Biology, Aravind Medical Research Foundation, Madurai, Tamil Nadu India
| | - Muthukkaruppan Veerappan
- 1Department of Immunology and Stem Cell Biology, Aravind Medical Research Foundation, Madurai, Tamil Nadu India
| | - Krishnadas Subbiah Ramasamy
- 2Glaucoma Clinic, Aravind Eye Hospital and Post Graduate Institute of Ophthalmology, Madurai, Tamil Nadu India
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Yam GHF, Seah X, Yusoff NZBM, Setiawan M, Wahlig S, Htoon HM, Peh GSL, Kocaba V, Mehta JS. Characterization of Human Transition Zone Reveals a Putative Progenitor-Enriched Niche of Corneal Endothelium. Cells 2019; 8:cells8101244. [PMID: 31614883 PMCID: PMC6829622 DOI: 10.3390/cells8101244] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 10/09/2019] [Accepted: 10/10/2019] [Indexed: 12/12/2022] Open
Abstract
: The corneal endothelium regulates corneal hydration to maintain the transparency of cornea. Lacking regenerative capacity, corneal endothelial cell loss due to aging and diseases can lead to corneal edema and vision loss. There is limited information on the existence of corneal endothelial progenitors. We conducted ultrastructural examinations and expression analyses on the human transition zone (TZ) at the posterior limbus of corneal periphery, to elucidate if the TZ harbored progenitor-like cells, and to reveal their niche characteristics. Within the narrow TZ (~190 μm width), the inner TZ-adjacent to the peripheral endothelium (PE)-contained cells expressing stem/progenitor markers (Sox2, Lgr5, CD34, Pitx2, telomerase). They were located on the inner TZ surface and in its underlying stroma. Lgr5 positive cells projected as multicellular clusters into the PE. Under transmission electron microscopy and serial block face-scanning electron microscopy and three-dimensional (3D) reconstruction, the terminal margin of Descemet's membrane was inserted beneath the TZ surface, with the distance akin to the inner TZ breadth. Porcine TZ cells were isolated and proliferated into a confluent monolayer and differentiated to cells expressing corneal endothelial markers (ZO1, Na+K+ATPase) on cell surface. In conclusion, we have identified a novel inner TZ containing progenitor-like cells, which could serve the regenerative potential for corneal endothelium.
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Affiliation(s)
- Gary Hin-Fai Yam
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore 169856, Singapore.
- Eye-Academic Clinical Program, Duke-National University of Singapore (NUS) Graduate Medical School, Singapore 169857, Singapore.
| | - Xinyi Seah
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore 169856, Singapore.
| | | | - Melina Setiawan
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore 169856, Singapore.
| | - Stephen Wahlig
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore 169856, Singapore.
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC 27705, USA.
| | - Hla Myint Htoon
- Eye-Academic Clinical Program, Duke-National University of Singapore (NUS) Graduate Medical School, Singapore 169857, Singapore.
- Data Science Group, Singapore Eye Research Institute, Singapore 169856, Singapore.
| | - Gary S L Peh
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore 169856, Singapore.
- Eye-Academic Clinical Program, Duke-National University of Singapore (NUS) Graduate Medical School, Singapore 169857, Singapore.
| | - Viridiana Kocaba
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore 169856, Singapore.
- Department of Ophthalmology, Claude Bernard Lyon 1 Université, 69622 Villeurbanne, France.
| | - Jodhbir S Mehta
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore 169856, Singapore.
- Eye-Academic Clinical Program, Duke-National University of Singapore (NUS) Graduate Medical School, Singapore 169857, Singapore.
- Singapore National Eye Centre, Singapore, Singapore 168751, Singapore.
- School of Material Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore.
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Kennedy S, Lace R, Carserides C, Gallagher AG, Wellings DA, Williams RL, Levis HJ. Poly-ε-lysine based hydrogels as synthetic substrates for the expansion of corneal endothelial cells for transplantation. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2019; 30:102. [PMID: 31485761 PMCID: PMC6726667 DOI: 10.1007/s10856-019-6303-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 08/21/2019] [Indexed: 06/10/2023]
Abstract
Dysfunction of the corneal endothelium (CE) resulting from progressive cell loss leads to corneal oedema and significant visual impairment. Current treatments rely upon donor allogeneic tissue to replace the damaged CE. A donor cornea shortage necessitates the development of biomaterials, enabling in vitro expansion of corneal endothelial cells (CECs). This study investigated the use of a synthetic peptide hydrogel using poly-ε-lysine (pεK), cross-linked with octanedioic-acid as a potential substrate for CECs expansion and CE grafts. PεK hydrogel properties were optimised to produce a substrate which was thin, transparent, porous and robust. A human corneal endothelial cell line (HCEC-12) attached and grew on pεK hydrogels as confluent monolayers after 7 days, whereas primary porcine CECs (pCECs) detached from the pεK hydrogel. Pre-adsorption of collagen I, collagen IV and fibronectin to the pεK hydrogel increased pCEC adhesion at 24 h and confluent monolayers formed at 7 days. Minimal cell adhesion was observed with pre-adsorbed laminin, chondroitin sulphate or commercial FNC coating mix (fibronectin, collagen and albumin). Functionalisation of the pεK hydrogel with synthetic cell binding peptide H-Gly-Gly-Arg-Gly-Asp-Gly-Gly-OH (RGD) or α2β1 integrin recognition sequence H-Asp-Gly-Glu-Ala-OH (DGEA) resulted in enhanced pCEC adhesion with the RGD peptide only. pCECs grown in culture at 5 weeks on RGD pεK hydrogels showed zonula occludins 1 staining for tight junctions and expression of sodium-potassium adenosine triphosphase, suggesting a functional CE. These results demonstrate the pεK hydrogel can be tailored through covalent binding of RGD to provide a surface for CEC attachment and growth. Thus, providing a synthetic substrate with a therapeutic application for the expansion of allogenic CECs and replacement of damaged CE.
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Affiliation(s)
- Stephnie Kennedy
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, 6 West Derby Street, Liverpool, L7 8TX, UK
| | - Rebecca Lace
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, 6 West Derby Street, Liverpool, L7 8TX, UK
| | - Constandinos Carserides
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, 6 West Derby Street, Liverpool, L7 8TX, UK
| | - Andrew G Gallagher
- SpheriTech Ltd, Business and Technical Park, The Heath, Runcorn, WA7 4QX, UK
| | - Donald A Wellings
- SpheriTech Ltd, Business and Technical Park, The Heath, Runcorn, WA7 4QX, UK
| | - Rachel L Williams
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, 6 West Derby Street, Liverpool, L7 8TX, UK.
| | - Hannah J Levis
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, 6 West Derby Street, Liverpool, L7 8TX, UK
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Wahlig S, Yam GHF, Chong W, Seah XY, Kocaba V, Ang M, Htoon HM, Tun TA, Ong HS, Mehta JS. Quantification of the Posterior Cornea Using Swept Source Optical Coherence Tomography. Transl Vis Sci Technol 2018; 7:2. [PMID: 30197834 PMCID: PMC6126962 DOI: 10.1167/tvst.7.5.2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 07/15/2018] [Indexed: 12/13/2022] Open
Abstract
Purpose We define optical coherence tomography (OCT) measurement parameters of the corneal endothelium/Descemet's membrane (DM) complex and peripheral transition zone (TZ) and describe these measurements in an ethnically Chinese population. Methods OCT images of the anterior segment and iridocorneal angle were obtained from 129 healthy Chinese subjects (129 eyes), aged 40 to 81 years. The scleral spur (SS) and Schwalbe's line (SL) were identified in each image. Endothelium/DM diameter, referred to as endothelial arc length (EAL), is the SL-to-SL distance. The SS-to-SL distance encompasses the TZ and trabecular meshwork (TM). Since the TZ cannot be visualized by OCT, a ratio of TZ-to-TZ+TM width was calculated from scanning electron microscopy (SEM) images obtained from 5 cadaveric corneas. The SS-to-SL distance was multiplied by this ratio to approximate in vivo TZ width. Results From SEM measurements, the relationship TZ = 0.20*(TZ+TM) was determined. From OCT measurements, mean EAL was 12.15 ± 0.58 mm and mean TZ width was 156 ± 20 μm. For eyes with horizontal and vertical images, vertical EAL was significantly greater than horizontal EAL (P = 0.03). Conclusions Corneal endothelium/DM diameter and TZ width can be obtained from OCT images. Although only combined TZ+TM is visualized on OCT, TZ width can be reasonably approximated. Translational Relevance Emerging procedures, like endothelial cell injection and DM transplantation (DMT), require accurate measurements of endothelium/DM size for preoperative planning. Size of the TZ, which may contain progenitor cells, also could contribute to endothelial regeneration in these procedures.
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Affiliation(s)
- Stephen Wahlig
- Singapore Eye Research Institute (SERI), Singapore.,Duke University School of Medicine, Durham, NC, USA
| | - Gary Hin-Fai Yam
- Singapore Eye Research Institute (SERI), Singapore.,Singapore National Eye Center (SNEC), Singapore
| | | | - Xin-Yi Seah
- Singapore Eye Research Institute (SERI), Singapore
| | - Viridiana Kocaba
- Singapore Eye Research Institute (SERI), Singapore.,Department of Ophthalmology, Edouard Herriot Hospital, Hospices Civils de Lyon, Lyon, France.,Université de Lyon, F-69000 Lyon, France; Université Lyon 1, F-69100 Villeurbanne, France
| | - Marcus Ang
- Singapore Eye Research Institute (SERI), Singapore.,Singapore National Eye Center (SNEC), Singapore.,Eye-ACP, Duke-NUS Graduate Medical School, Singapore.,Moorfields Eye Hospital, London, UK
| | - Hla Myint Htoon
- Singapore Eye Research Institute (SERI), Singapore.,Eye-ACP, Duke-NUS Graduate Medical School, Singapore
| | - Tin A Tun
- Singapore Eye Research Institute (SERI), Singapore.,Singapore National Eye Center (SNEC), Singapore
| | - Hon Shing Ong
- Singapore Eye Research Institute (SERI), Singapore.,Singapore National Eye Center (SNEC), Singapore.,Moorfields Eye Hospital, London, UK
| | - Jodhbir S Mehta
- Singapore Eye Research Institute (SERI), Singapore.,Singapore National Eye Center (SNEC), Singapore.,Eye-ACP, Duke-NUS Graduate Medical School, Singapore
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Williams R, Lace R, Kennedy S, Doherty K, Levis H. Biomaterials for Regenerative Medicine Approaches for the Anterior Segment of the Eye. Adv Healthc Mater 2018; 7:e1701328. [PMID: 29388397 DOI: 10.1002/adhm.201701328] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 12/22/2017] [Indexed: 12/13/2022]
Abstract
The role of biomaterials in tissue engineering and regenerative medicine strategies to treat vision loss associated with damage to tissues in the anterior segment of the eye has been studied for several years. This has mostly involved replacement and support for the cornea and conjunctiva. These are complex tissues with specific functional requirements for different parts of the tissue. Amniotic membrane (AM) is used in clinical practice to transplant autologous or allogenic cells to the corneal surface. Fibrin gels have also progressed to clinical use under specific conditions. Alternatives to AM such as collagen gels, other natural materials, for example keratin and silks, and synthetic polymers have received considerable attention in laboratory and animal studies. This experience is building a body of evidence to demonstrate the potential of tissue engineering and regenerative medicine in corneal and conjunctival reconstruction and can also lead to other applications in the anterior segment of the eye, for example, the trabecular meshwork. There is a real clinical need for new procedures to overcome vision loss but there are also opportunities for developments in ocular applications to lead to biomaterials innovations for use in other clinical areas.
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Affiliation(s)
- Rachel Williams
- Department of Eye and Vision Science, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
| | - Rebecca Lace
- Department of Eye and Vision Science, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
| | - Stephnie Kennedy
- Department of Eye and Vision Science, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
| | - Kyle Doherty
- Department of Eye and Vision Science, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
| | - Hannah Levis
- Department of Eye and Vision Science, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
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Lovatt M, Yam GHF, Peh GS, Colman A, Dunn NR, Mehta JS. Directed differentiation of periocular mesenchyme from human embryonic stem cells. Differentiation 2018; 99:62-69. [DOI: 10.1016/j.diff.2017.11.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 10/31/2017] [Accepted: 11/08/2017] [Indexed: 12/13/2022]
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19
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Soh YQ, Peh GSL, Mehta JS. Translational issues for human corneal endothelial tissue engineering. J Tissue Eng Regen Med 2016; 11:2425-2442. [DOI: 10.1002/term.2131] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 11/19/2015] [Accepted: 12/10/2015] [Indexed: 12/13/2022]
Affiliation(s)
- Yu Qiang Soh
- Tissue Engineering and Stem Cell Group; Singapore Eye Research Institute; Singapore
- Singapore National Eye Centre; Singapore
| | - Gary S. L. Peh
- Tissue Engineering and Stem Cell Group; Singapore Eye Research Institute; Singapore
- Ophthalmology Academic Clinical Programme; Duke-NUS Graduate Medical School; Singapore
| | - Jodhbir S. Mehta
- Tissue Engineering and Stem Cell Group; Singapore Eye Research Institute; Singapore
- Singapore National Eye Centre; Singapore
- Ophthalmology Academic Clinical Programme; Duke-NUS Graduate Medical School; Singapore
- Department of Clinical Sciences; Duke-NUS Graduate Medical School; Singapore
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