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Murugan S, de Campos VS, Ghag SA, Ng M, Shyam R. Characterization of a Novel Mouse Model for Fuchs Endothelial Corneal Dystrophy. Invest Ophthalmol Vis Sci 2024; 65:18. [PMID: 38587441 PMCID: PMC11005065 DOI: 10.1167/iovs.65.4.18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 03/23/2024] [Indexed: 04/09/2024] Open
Abstract
Purpose Fuchs endothelial corneal dystrophy (FECD) is a progressive blinding disorder, characterized by increased corneal endothelial excrescences (guttae), corneal endothelial cell loss, and edema. These symptoms are hypothesized to be caused by changes in the extracellular matrix (ECM) and mitochondrial dysfunction in the corneal endothelium. Despite this clinical and biological relevance, a comprehensive animal model that recapitulates all the major disease characteristics is currently unavailable. In this study, we develop such a model to improve our understanding of the signaling pathways involved in the FECD progression and develop strategies for early intervention. Method To generate a comprehensive FECD model, we generated a double mutant mouse bearing tamoxifen-inducible knockdown of Slc4a11 and the Col8a2 (Q455K) mutation. We performed optical coherence tomography (OCT) and in vivo confocal microscopy using the Heidelberg Retinal Tomography 3 - Rostock Cornea module (HRT3-RCM) on the mice at 5 weeks of age before tamoxifen feeding to establish baseline values for corneal thickness, endothelial cell density, and test for the presence of guttae. We measured these parameters again post-tamoxifen treatment at 16 weeks of age. We collected corneas at 16 weeks to perform histopathology, immunofluorescence staining for tight junctions, adherens junctions, and oxidative stress. We evaluated endothelial pump function using a lactate assay. Results The double mutant tamoxifen-fed animals showed the presence of guttae, and displayed increased corneal thickness and decreased endothelial cell density. Endothelial cells showed altered morphology with disrupted adherens junctions and elevated reactive oxygen species (ROS). Finally, we found that stromal lactate concentrations were elevated in the double mutant mice, indicative of compromised endothelial pump function. Conclusions Overall, this mouse model recapitulates all the important phenotypic features associated with FECD.
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Affiliation(s)
- Subashree Murugan
- Vision Science Program, School of Optometry, Indiana University Bloomington, Indiana, United States
| | - Viviane Souza de Campos
- Vision Science Program, School of Optometry, Indiana University Bloomington, Indiana, United States
| | - Sachin Anil Ghag
- Vision Science Program, School of Optometry, Indiana University Bloomington, Indiana, United States
| | - Matthew Ng
- Department of Biology, Indiana University Bloomington, Indiana, United States
| | - Rajalekshmy Shyam
- Vision Science Program, School of Optometry, Indiana University Bloomington, Indiana, United States
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2
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Thomasy SM, Leonard BC, Greiner MA, Skeie JM, Raghunathan VK. Squishy matters - Corneal mechanobiology in health and disease. Prog Retin Eye Res 2024; 99:101234. [PMID: 38176611 PMCID: PMC11193890 DOI: 10.1016/j.preteyeres.2023.101234] [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: 09/01/2023] [Revised: 12/22/2023] [Accepted: 12/27/2023] [Indexed: 01/06/2024]
Abstract
The cornea, as a dynamic and responsive tissue, constantly interacts with mechanical forces in order to maintain its structural integrity, barrier function, transparency and refractive power. Cells within the cornea sense and respond to various mechanical forces that fundamentally regulate their morphology and fate in development, homeostasis and pathophysiology. Corneal cells also dynamically regulate their extracellular matrix (ECM) with ensuing cell-ECM crosstalk as the matrix serves as a dynamic signaling reservoir providing biophysical and biochemical cues to corneal cells. Here we provide an overview of mechanotransduction signaling pathways then delve into the recent advances in corneal mechanobiology, focusing on the interplay between mechanical forces and responses of the corneal epithelial, stromal, and endothelial cells. We also identify species-specific differences in corneal biomechanics and mechanotransduction to facilitate identification of optimal animal models to study corneal wound healing, disease, and novel therapeutic interventions. Finally, we identify key knowledge gaps and therapeutic opportunities in corneal mechanobiology that are pressing for the research community to address especially pertinent within the domains of limbal stem cell deficiency, keratoconus and Fuchs' endothelial corneal dystrophy. By furthering our understanding corneal mechanobiology, we can contextualize discoveries regarding corneal diseases as well as innovative treatments for them.
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Affiliation(s)
- Sara M Thomasy
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California - Davis, Davis, CA, United States; Department of Ophthalmology & Vision Science, School of Medicine, University of California - Davis, Davis, CA, United States; California National Primate Research Center, Davis, CA, United States.
| | - Brian C Leonard
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California - Davis, Davis, CA, United States; Department of Ophthalmology & Vision Science, School of Medicine, University of California - Davis, Davis, CA, United States
| | - Mark A Greiner
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA, United States; Iowa Lions Eye Bank, Coralville, IA, United States
| | - Jessica M Skeie
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA, United States; Iowa Lions Eye Bank, Coralville, IA, United States
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3
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Yan D, Ouyang W, Lin J, Liu Z. Smart coating by thermo-sensitive Pluronic F-127 for enhanced corneal healing via delivery of biological macromolecule progranulin. Int J Biol Macromol 2023; 253:127586. [PMID: 37866564 DOI: 10.1016/j.ijbiomac.2023.127586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 10/18/2023] [Accepted: 10/19/2023] [Indexed: 10/24/2023]
Abstract
As a leading cause of vision impairment and blindness, corneal alkali burns lead to long-term visual deterioration or even permanent visual impairment while effective treatment strategies remain a challenge. Herein, a thermo-sensitive hydrogel with the combination of multi-functional protein progranulin (PGRN), a biological macromolecule consisting of several hundred amino acids and possessing a high molecular weight, is efficiently prepared through a convenient stirring and mixing at the low temperature. The hydrogel can be easily administrated to the ocular surface contacting with the cornea, which can be immediately transformed into gel-like state due to the thermo-responsive behavior, realizing a site-specific coating to isolate further external stimulation. The smart coating not only exhibits excellent transparency and biocompatibility, but also presents a constant delivery of PGRN, creating a nutritious and supportive micro-environment for the ocular surface. The results show that the prepared functional hydrogel can efficiently suppress inflammation, accelerate re-epithelization, and intriguingly enhance axonal regeneration via modulation of multiple signaling pathways, indicating the novel designed HydrogelPGRN is a promising therapy option for serious corneal injury.
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Affiliation(s)
- Dan Yan
- Eye Institute of Xiamen University, School of Medicine, Xiamen University, Xiamen University affiliated Xiamen Eye Center, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Fujian Engineering and Research Center of Eye Regenerative Medicine, Department of Ophthalmology, Xiang'an Hospital of Xiamen University, Xiamen, Fujian 361005, China
| | - Weijie Ouyang
- Eye Institute of Xiamen University, School of Medicine, Xiamen University, Xiamen University affiliated Xiamen Eye Center, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Fujian Engineering and Research Center of Eye Regenerative Medicine, Department of Ophthalmology, Xiang'an Hospital of Xiamen University, Xiamen, Fujian 361005, China
| | - Jinyou Lin
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, China.
| | - Zuguo Liu
- Eye Institute of Xiamen University, School of Medicine, Xiamen University, Xiamen University affiliated Xiamen Eye Center, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Fujian Engineering and Research Center of Eye Regenerative Medicine, Department of Ophthalmology, Xiang'an Hospital of Xiamen University, Xiamen, Fujian 361005, China; Department of Ophthalmology, the First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, China.
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4
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Cai Y, Chen J, Sun H, Zhou T, Cai X, Fu Y. Crosstalk between TRPV1 and immune regulation in Fuchs endothelial corneal dystrophy. Clin Immunol 2023; 254:109701. [PMID: 37482117 DOI: 10.1016/j.clim.2023.109701] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/25/2023] [Accepted: 07/18/2023] [Indexed: 07/25/2023]
Abstract
Fuchs endothelial corneal dystrophy (FECD) is the leading indication for corneal transplantation worldwide. Our aim was to investigate the role of transient receptor potential vanilloid subtype 1 (TRPV1) and the associated immune regulation contributing to this pathological condition. Significant upregulation of TRPV1 was detected in the H2O2-induced in vitro FECD model. Based on gene expression microarray dataset GSE142538 and in vitro results, a comprehensive immune landscape was studied and a negative correlation was found between TRPV1 with different immune cells, especially regulatory T cells (Tregs). Functional analyses of the 313 TRPV1-related differentially expressed genes (DEGs) revealed the involvement of TRP-regulated calcium transport, as well as inflammatory and immune pathways. Four TRPV1-related core genes (MAPK14, GNB1, GNAQ, and ARRB2) were screened, validated by microarray dataset GSE112039 and the combined validation dataset E-GEAD-399 & 564, and verified by in vitro experiments. Our study suggested a potential crosstalk between TRPV1 and immune regulation contributing to FECD pathogenesis. The identified pivotal biomarkers and immune-related pathways provide a novel framework for future mechanistic and therapeutic studies of FECD.
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Affiliation(s)
- Yuchen Cai
- Department of Ophthalmology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Jin Chen
- Department of Ophthalmology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Hao Sun
- Department of Ophthalmology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Tianyi Zhou
- Department of Ophthalmology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Xueyao Cai
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Yao Fu
- Department of Ophthalmology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China.
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Zhu YT, Tighe S, Chen SL, Zhang Y, Chen SY, Kao WWY, Tseng SCG. Manufacturing of human corneal endothelial grafts. Ocul Surf 2023; 29:301-310. [PMID: 37268293 PMCID: PMC10529356 DOI: 10.1016/j.jtos.2023.05.004] [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: 02/06/2023] [Revised: 05/05/2023] [Accepted: 05/12/2023] [Indexed: 06/04/2023]
Abstract
PURPOSE Human corneal endothelial cells (HCECs) play a significant role in maintaining visual function. However, these cells are notorious for their limited proliferative capacity in vivo. Current treatment of corneal endothelial dysfunction resorts to corneal transplantation. Herein we describe an ex vivo engineering method to manufacture HCEC grafts suitable for transplantation through reprogramming into neural crest progenitors. METHODS HCECs were isolated by collagenase A from stripped Descemet membrane of cadaveric corneoscleral rims, and induced reprogramming via knockdown with p120 and Kaiso siRNAs on collagen IV-coated atelocollagen. Engineered HCEC grafts were released after assessing their identity, potency, viability, purity and sterility. Phase contrast was used for monitoring cell shape, graft size, and cell density. Immunostaining was used to determine the normal HCEC phenotype with expression of N-cadherin, ZO-1, ATPase, acetyl-α-tubulin, γ-tubulin, p75NTR, α-catenin, β-catenin, and F-actin. Stability of manufactured HCEC graft was evaluated after transit and storage for up to 3 weeks. The pump function of HCEC grafts was measured by lactate efflux. RESULTS One HCEC graft suitable for corneal transplantation was generated from 1/8th of the donor corneoscleral rim with normal hexagonal cell shape, density, and phenotype. The manufactured grafts were stable for up to 3 weeks at 37 °C or up to 1 week at 22 °C in MESCM medium and after transcontinental shipping at room temperature by retaining normal morphology (hexagonal, >2000 cells/mm2, >8 mm diameter), phenotype, and pump function. CONCLUSIONS This regenerative strategy through knockdown with p120 and Kaiso siRNAs can be used to manufacture HCEC grafts with normal phenotype, morphology and pump function following prolonged storage and shipping.
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Affiliation(s)
| | - Sean Tighe
- R&D Department, BioTissue, Miami, FL, 33126, USA
| | | | - Yuan Zhang
- R&D Department, BioTissue, Miami, FL, 33126, USA
| | - Szu-Yu Chen
- R&D Department, BioTissue, Miami, FL, 33126, USA
| | - Winston W Y Kao
- Department of Ophthalmology, University of Cincinnati, 2600 Clifton Ave, Cincinnati, OH, 45220, USA
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Shilpashree PS, Ravi T, Thanuja MY, Anupama C, Ranganath SH, Suresh KV, Srinivas SP. Grading the Severity of Damage to the Perijunctional Actomyosin Ring and Zonula Occludens-1 of the Corneal Endothelium by Ensemble Learning Methods. J Ocul Pharmacol Ther 2023. [PMID: 36930844 DOI: 10.1089/jop.2022.0154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023] Open
Abstract
Purpose: In many epithelia, including the corneal endothelium, intracellular/extracellular stresses break down the perijunctional actomyosin ring (PAMR) and zonula occludens-1 (ZO-1) at the apical junctions. This study aims to grade the severity of damage to PAMR and ZO-1 through machine learning. Methods: Immunocytochemical images of PAMR and ZO-1 were drawn from recent studies on the corneal endothelium subjected to hypothermia and oxidative stress. The images were analyzed for their morphological (e.g., Hu moments) and textural features (based on gray-level co-occurrence matrix [GLCM] and Gabor filters). The extracted features were ranked by SHapley analysis and analysis of variance. Then top features were used to grade the severity of damage using a suite of ensemble classifiers, including random forest, bagging classifier (BC), AdaBoost, extreme gradient boosting, and stacking classifier. Results: A partial set of features from GLCM, along with Hu moments and the number of hexagons, enabled the classification of damage to PAMR into Control, Mild, Moderate, and Severe with the area under the receiver operating characteristics curve (AUC) = 0.92 and F1 score = 0.77 with BC. In contrast, a bank of Gabor filters provided a partial set of features that could be combined with Hu moments, branch length, and sharpness for the classification of ZO-1 images into four levels with AUC = 0.95 and F1 score of 0.8 with BC. Conclusions: We have developed a workflow that enables the stratification of damage to PAMR and ZO-1. The approach can be applied to similar data during drug discovery or pathophysiological studies of epithelia.
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Affiliation(s)
- Palanahalli S Shilpashree
- Department of Electronics and Communication, Siddaganga Institute of Technology (Affiliated to VTU, Belagavi), Tumakuru, India
| | - Tapanmitra Ravi
- School of Optometry, Indiana University, Bloomington, Indiana, USA
| | - M Y Thanuja
- Department of Chemical Engineering, and Siddaganga Institute of Technology (Affiliated to VTU, Belagavi), Tumakuru, India
| | - Chalimeswamy Anupama
- Department of Biotechnology, Siddaganga Institute of Technology (Affiliated to VTU, Belagavi), Tumakuru, India
| | - Sudhir H Ranganath
- Department of Chemical Engineering, and Siddaganga Institute of Technology (Affiliated to VTU, Belagavi), Tumakuru, India
| | - Kaggere V Suresh
- Department of Electronics and Communication, Siddaganga Institute of Technology (Affiliated to VTU, Belagavi), Tumakuru, India
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7
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Anupama C, Shettar A, Ranganath SH, Srinivas SP. Experimental Oxidative Stress Breaks Down the Barrier Function of the Corneal Endothelium. J Ocul Pharmacol Ther 2023; 39:70-79. [PMID: 36346320 DOI: 10.1089/jop.2022.0093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Purpose: The fluid pump and barrier functions of the corneal endothelium maintain stromal deturgescence required for corneal transparency. The effect of oxidative stress, a hallmark of Fuchs endothelial corneal dystrophy (FECD), on the endothelial barrier function has been investigated. Methods: The endothelium of porcine corneas ex vivo was exposed to (1) membrane permeable oxidants (H2O2, 100 μM, 1 h; tert-butyl-hydroperoxide, 100 μM, 1 h), or (2) ultraviolet A (UVA) with photosensitizers for 15 min, riboflavin (50 μM) or tryptophan (Trp) (100 μM). The effects on the apical junction complex were analyzed by (1) immunostaining the perijunctional actomyosin ring (PAMR) and ZO-1 and (2) assessment of paracellular flux of fluorescein isothiocyanate (FITC)-avidin across cultured endothelial cells grown on biotinylated-gelatin film. The extent of oxidative stress was quantified by changes in intracellular reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) in addition to lipid peroxidation and release of lactate dehydrogenase (LDH). Results: Both methods of oxidative stress led to the disruption of PAMR and ZO-1 concurrent with changes in ROS levels, depolarization of MMP, increased lipid peroxidation, elevated LDH release, and increased permeability of FITC-avidin. The effects of direct oxidants were opposed by SB-203580 [p38 mitogen-activating protein (MAP) kinase inhibitor; 10 μM]. The damage by UVA+photosensitizers was blocked by extracellular catalase (10,000 U/mL). Conclusions: (1) Acute oxidative stress breaks down the barrier function through destruction of PAMR in a p38 MAP kinase-dependent manner. (2) UVA+photosensitizers elicit the breakdown of PAMR via type I reactions, involving H2O2 release. (3) Blocking the oxidative stress prevents loss of barrier function, which could be helpful in the therapeutics of FECD.
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Affiliation(s)
- C Anupama
- Department of Biotechnology, Department of Chemical Engineering, Siddaganga Institute of Technology, Tumakuru, India.,Bio-INvENT Lab, Department of Chemical Engineering, Siddaganga Institute of Technology, Tumakuru, India
| | - Abhijith Shettar
- Department of Biotechnology, MS Ramaiah Institute of Technology, Bengaluru, India
| | - Sudhir H Ranganath
- Bio-INvENT Lab, Department of Chemical Engineering, Siddaganga Institute of Technology, Tumakuru, India
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So S, Park Y, Kang SS, Han J, Sunwoo JH, Lee W, Kim J, Ye EA, Kim JY, Tchah H, Kang E, Lee H. Therapeutic Potency of Induced Pluripotent Stem-Cell-Derived Corneal Endothelial-like Cells for Corneal Endothelial Dysfunction. Int J Mol Sci 2022; 24:701. [PMID: 36614165 PMCID: PMC9821383 DOI: 10.3390/ijms24010701] [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: 07/03/2022] [Revised: 12/29/2022] [Accepted: 12/29/2022] [Indexed: 01/03/2023] Open
Abstract
Corneal endothelial cells (CECs) do not proliferate or recover after illness or injury, resulting in decreased cell density and loss of pump/barrier function. Considering the shortage of donor cornea, it is vital to establish robust methods to generate CECs from induced pluripotent stem cells (iPSCs). We investigated the efficacy and safety of transplantation of iPSC-derived CECs into a corneal endothelial dysfunction (CED) rabbit model. iPSCs were generated from human fibroblasts. We characterized iPSCs by demonstrating the gene expression of the PSC markers OCT4, SOX2, TRA-1-60, and NANOG, teratoma formation, and differentiation into three germ layers. Differentiation of iPSCs into CECs was induced via neural crest cell (NCC) induction. CEC markers were detected using immunofluorescence and gene expression was analyzed using quantitative real-time PCR (qRT-PCR). After culturing iPSC-derived NCCs, we found the expression of zona occludens-1 (ZO-1) and Na+/K+ ATPase and a hexagonal morphology. ATP1A1, COL8A1, and AQP1 mRNA expression was higher in iPSC-derived CECs than in iPSCs and NCCs. We performed an injection of iPSC-derived CECs into the anterior chamber of a CED rabbit model and found improved levels of corneal transparency. We also found increased numbers of ZO-1- and ATP1A1-positive cells in rabbit corneas in the iPSC-derived CEC transplantation group. Usage of the coating material vitronectin (VTN) and fasudil resulted in good levels of CEC marker expression, demonstrated with Western blotting and immunocytochemistry. Combination of the VTN coating material and fasudil, instead of FNC mixture and Y27632, afforded the best results in terms of CEC differentiation's in vitro and in vivo efficacy. Successful transplantation of CEC-like cells into a CED animal model confirms the therapeutic efficacy of these cells, demonstrated by the restoration of corneal clarity. Our results suggest that iPSC-derived CECs can be a promising cellular resource for the treatment of CED.
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Affiliation(s)
- Seongjun So
- Department of Biomedical Science, CHA Advanced Research Institute, College of Life Science and Center for Embryo and Stem Cell Research, CHA University, Seongnam 13488, Republic of Korea
| | - Yoonkyung Park
- Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Soon Suk Kang
- Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Jongsuk Han
- Department of Biomedical Science, CHA Advanced Research Institute, College of Life Science and Center for Embryo and Stem Cell Research, CHA University, Seongnam 13488, Republic of Korea
| | - Jeong Hye Sunwoo
- Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Whanseo Lee
- Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Jin Kim
- Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Eun Ah Ye
- Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Jae Yong Kim
- Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Hungwon Tchah
- Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Eunju Kang
- Department of Biomedical Science, CHA Advanced Research Institute, College of Life Science and Center for Embryo and Stem Cell Research, CHA University, Seongnam 13488, Republic of Korea
| | - Hun Lee
- Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
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Lindstrom RL, Lewis AE, Holland EJ, Sheppard JD, Hovanesian JA, Senchyna M, Hollander DA. Phase 2, Randomized, Open-Label Parallel-Group Study of Two Dosing Regimens of Netarsudil for the Treatment of Corneal Edema Due to Fuchs Corneal Dystrophy. J Ocul Pharmacol Ther 2022; 38:657-663. [PMID: 36327101 PMCID: PMC9784611 DOI: 10.1089/jop.2022.0069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Background: This phase 2 study evaluated the therapeutic potential of netarsudil to reduce corneal edema and to improve vision in patients with Fuchs corneal dystrophy (FCD). Methods: Patients (N = 40) with baseline central corneal thickness (CCT) of ≥600 μm and best-corrected visual acuity (BCVA) of 70-20 letters (20/40-20/400 Snellen equivalent) were randomized 1:1 to receive netarsudil once a day (QD) or twice a day (BID) for 8 weeks. Primary endpoint was mean CCT change from baseline at week 4. Results: Netarsudil QD and BID significantly reduced CCT at week 4 [mean change (standard error of mean), 28.4 (7.99) μm, P = 0.0021; and 20.1 (8.75) μm, P = 0.0335, respectively]. Five (12.5%) patients achieved complete resolution of corneal edema at week 4. BCVA improved by 3.2 (2.76) letters with QD and 1.5 (2.84) letters with BID, and 10 (25%) patients [5 with QD (P = 0.0078) and 5 with BID (P = 0.0096)] gained ≥10 letters at week 4. Improvements in CCT and vision were observed at week 2 and persisted at week 8, without significant differences between the 2 doses at any time point. Netarsudil QD significantly improved visual acuity and glare factor scores on the Visual Function and Corneal Health Status (V-FUCHS) questionnaire at weeks 4 and 8 (mean change, -0.4 to -0.3; P ≤ 0.0200). Netarsudil was well tolerated. Reticular edema developed in one (2.5%) patient with BID, which resolved with treatment discontinuation. Conclusions: Netarsudil QD led to significant reductions in corneal edema as well as improvements in vision and patient-reported symptoms of glare and visual impairment in patients with FCD. Clinical Trial Registration Number: NCT04498169.
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Affiliation(s)
- Richard L. Lindstrom
- Minnesota Eye Consultants, Minneapolis, Minnesota, USA.,Address correspondence to: Dr. Richard L. Lindstrom, Minnesota Eye Consultants, 710 E 24th Street, Suite 100, Minneapolis, MN 55404, USA
| | - Amber E. Lewis
- Aerie Pharmaceuticals, Inc., Durham, North Carolina, USA
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10
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Thanuja MY, Ranganath SH, Srinivas SP. Role of Oxidative Stress in the Disruption of the Endothelial Apical Junctional Complex During Corneal Cold Storage. J Ocul Pharmacol Ther 2022; 38:664-681. [PMID: 36255463 DOI: 10.1089/jop.2022.0082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Purpose: To characterize the impact of corneal cold storage (CS) on the endothelial apical junctional complex (AJC). Methods: Porcine corneas were held in CS (4°C; 1-7 days) with Cornisol™ preservation medium supplemented with epothilone B (EpoB; microtubule stabilizer; 100 nM), SB-203580 (p38 mitogen-activated protein [MAP] kinase inhibitor; 20 μM), or antioxidants (quercetin, 100 μM; vitamin E, 1 mM; deferoxamine, an iron chelator, 10 mM). After CS termination, the damage to endothelial AJC was characterized by imaging perijunctional actomyosin ring (PAMR) and zonula occludens (ZO-1). The effects of EpoB and SB-203580 were characterized by imaging microtubules. The loss in the barrier function was assessed in cultured cells grown on biotin-coated gelatin by permeability to fluorescein isothiocyanate (FITC)-avidin. The accumulation of reactive oxygen species (ROS), altered mitochondrial membrane potential (MMP), lipid peroxidation, and lactate dehydrogenase (LDH) release were also determined in response to CS. Results: CS led to the loss of microtubules, destruction of PAMR, and breakdown of ZO-1 in the endothelium. The severity of damage increased when CS was prolonged. Although rewarming of the tissue increased the damage, the effect was marginal. CS also induced accumulation of ROS, alteration in MMP, lipid peroxidation, enhanced LDH release, and increased permeability to FITC-avidin. These changes were opposed by EpoB, SB-203580, and antioxidants. Conclusion: Corneal CS destroys AJC of the endothelium, leading to loss of its barrier function. The effects were surmounted by microtubule stabilization, p38 MAP kinase inhibition, and antioxidants. Thus, there is potential for reformulation of the preservation medium to maintain the health of the donor corneal endothelium before transplantation.
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Affiliation(s)
- M Y Thanuja
- Bio-INvENT Lab, Department of Chemical Engineering, Siddaganga Institute of Technology, Tumakuru, India
| | - Sudhir H Ranganath
- Bio-INvENT Lab, Department of Chemical Engineering, Siddaganga Institute of Technology, Tumakuru, India
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Chen A, Harris ZB, Virk A, Abazari A, Varadaraj K, Honkanen R, Arbab MH. Assessing Corneal Endothelial Damage Using Terahertz Time-Domain Spectroscopy and Support Vector Machines. SENSORS (BASEL, SWITZERLAND) 2022; 22:9071. [PMID: 36501773 PMCID: PMC9735956 DOI: 10.3390/s22239071] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 11/16/2022] [Accepted: 11/19/2022] [Indexed: 06/17/2023]
Abstract
The endothelial layer of the cornea plays a critical role in regulating its hydration by actively controlling fluid intake in the tissue via transporting the excess fluid out to the aqueous humor. A damaged corneal endothelial layer leads to perturbations in tissue hydration and edema, which can impact corneal transparency and visual acuity. We utilized a non-contact terahertz (THz) scanner designed for imaging spherical targets to discriminate between ex vivo corneal samples with intact and damaged endothelial layers. To create varying grades of corneal edema, the intraocular pressures of the whole porcine eye globe samples (n = 19) were increased to either 25, 35 or 45 mmHg for 4 h before returning to normal pressure levels at 15 mmHg for the remaining 4 h. Changes in tissue hydration were assessed by differences in spectral slopes between 0.4 and 0.8 THz. Our results indicate that the THz response of the corneal samples can vary according to the differences in the endothelial cell density, as determined by SEM imaging. We show that this spectroscopic difference is statistically significant and can be used to assess the intactness of the endothelial layer. These results demonstrate that THz can noninvasively assess the corneal endothelium and provide valuable complimentary information for the study and diagnosis of corneal diseases that perturb the tissue hydration.
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Affiliation(s)
- Andrew Chen
- Department of Biomedical Engineering, Stony Brook University, 100 Nicolls Rd, Stony Brook, NY 11794, USA
| | - Zachery B. Harris
- Department of Biomedical Engineering, Stony Brook University, 100 Nicolls Rd, Stony Brook, NY 11794, USA
| | - Arjun Virk
- Department of Biomedical Engineering, Stony Brook University, 100 Nicolls Rd, Stony Brook, NY 11794, USA
| | - Azin Abazari
- Department of Ophthalmology, Renaissance School of Medicine, 101 Nicolls Rd, Stony Brook, NY 11794, USA
| | - Kulandaiappan Varadaraj
- Department of Physiology and Biophysics, Renaissance School of Medicine, 101 Nicolls Rd, Stony Brook, NY 11794, USA
| | - Robert Honkanen
- Department of Ophthalmology, Renaissance School of Medicine, 101 Nicolls Rd, Stony Brook, NY 11794, USA
| | - Mohammad Hassan Arbab
- Department of Biomedical Engineering, Stony Brook University, 100 Nicolls Rd, Stony Brook, NY 11794, USA
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Arsenijevic Y, Berger A, Udry F, Kostic C. Lentiviral Vectors for Ocular Gene Therapy. Pharmaceutics 2022; 14:pharmaceutics14081605. [PMID: 36015231 PMCID: PMC9414879 DOI: 10.3390/pharmaceutics14081605] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 07/14/2022] [Accepted: 07/22/2022] [Indexed: 12/10/2022] Open
Abstract
This review offers the basics of lentiviral vector technologies, their advantages and pitfalls, and an overview of their use in the field of ophthalmology. First, the description of the global challenges encountered to develop safe and efficient lentiviral recombinant vectors for clinical application is provided. The risks and the measures taken to minimize secondary effects as well as new strategies using these vectors are also discussed. This review then focuses on lentiviral vectors specifically designed for ocular therapy and goes over preclinical and clinical studies describing their safety and efficacy. A therapeutic approach using lentiviral vector-mediated gene therapy is currently being developed for many ocular diseases, e.g., aged-related macular degeneration, retinopathy of prematurity, inherited retinal dystrophies (Leber congenital amaurosis type 2, Stargardt disease, Usher syndrome), glaucoma, and corneal fibrosis or engraftment rejection. In summary, this review shows how lentiviral vectors offer an interesting alternative for gene therapy in all ocular compartments.
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Affiliation(s)
- Yvan Arsenijevic
- Unit Retinal Degeneration and Regeneration, Department of Ophthalmology, University of Lausanne, Jules-Gonin Eye Hospital, Fondation Asile des Aveugles, 1004 Lausanne, Switzerland;
- Correspondence: (Y.A.); (C.K.)
| | - Adeline Berger
- Group Epigenetics of ocular diseases, Department of Ophthalmology, University of Lausanne, Jules-Gonin Eye Hospital, Fondation Asile des Aveugles, 1004 Lausanne, Switzerland;
| | - Florian Udry
- Unit Retinal Degeneration and Regeneration, Department of Ophthalmology, University of Lausanne, Jules-Gonin Eye Hospital, Fondation Asile des Aveugles, 1004 Lausanne, Switzerland;
| | - Corinne Kostic
- Group for Retinal Disorder Research, Department of Ophthalmology, University of Lausanne, Jules-Gonin Eye Hospital, Fondation Asile des Aveugles, 1004 Lausanne, Switzerland
- Correspondence: (Y.A.); (C.K.)
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Chalimeswamy A, Thanuja MY, Ranganath SH, Pandya K, Kompella UB, Srinivas SP. Oxidative Stress Induces a Breakdown of the Cytoskeleton and Tight Junctions of the Corneal Endothelial Cells. J Ocul Pharmacol Ther 2021; 38:74-84. [PMID: 34818079 DOI: 10.1089/jop.2021.0037] [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] [Indexed: 12/30/2022] Open
Abstract
Purpose: To investigate the impact of oxidative stress, which is a hallmark of Fuchs dystrophy, on the barrier function of the corneal endothelial cells. Methods: Experiments were carried out with cultured bovine and porcine corneal endothelial cells. For oxidative stress, cells were supplemented with riboflavin (Rf) and exposed to UV-A (15-30 min) to induce Type-1 photochemical reactions that release H2O2. The effect of the stress on the barrier function was assayed by transendothelial electrical resistance (TER) measurement. In addition, the associated changes in the organization of the microtubules, perijunctional actomyosin ring (PAMR), and ZO-1 were evaluated by immunocytochemistry, which was also repeated after direct exposure to H2O2 (100 μM, 1 h). Results: Exposure to H2O2 led to the disassembly of microtubules and the destruction of PAMR. In parallel, the contiguous locus of ZO-1 was disrupted, marking a loss of barrier integrity. Accordingly, a sustained loss in TER was induced when cells in the Rf-supplemented medium were exposed to UV-A. However, the addition of catalase (7,000 U/mL) to rapidly decompose H2O2 limited the loss in TER. Furthermore, the adverse effects on microtubules, PAMR, and ZO-1 were suppressed by including catalase, ascorbic acid (1 mM; 30 min), or pretreatment with p38 MAP kinase inhibitor (SB-203580; 10 μM, 1 h). Conclusions: Acute oxidative stress induces microtubule disassembly by a p38 MAP kinase-dependent mechanism, leading to the destruction of PAMR and loss of barrier function. The response to oxidative stress is reminiscent of the (TNF-α)-induced breakdown of barrier failure in the corneal endothelium.
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Affiliation(s)
- Anupama Chalimeswamy
- Department of Biotechnology, Siddaganga Institute of Technology, Tumakuru, India.,Bio-INvENT Lab, Department of Chemical Engineering, Siddaganga Institute of Technology, Tumakuru, India
| | | | - Sudhir H Ranganath
- Bio-INvENT Lab, Department of Chemical Engineering, Siddaganga Institute of Technology, Tumakuru, India
| | - Kaveet Pandya
- School of Optometry, Indiana University, Bloomington, Indiana, USA
| | - Uday B Kompella
- Pharmaceutical Sciences, University of Colorado, Aurora, Colorado, USA
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Zhao MJ, Jiang HR, Sun JW, Wang ZA, Hu B, Zhu CR, Yin XH, Chen MM, Ma XC, Zhao WD, Luan ZG. Roles of RAGE/ROCK1 Pathway in HMGB1-Induced Early Changes in Barrier Permeability of Human Pulmonary Microvascular Endothelial Cell. Front Immunol 2021; 12:697071. [PMID: 34745088 PMCID: PMC8564108 DOI: 10.3389/fimmu.2021.697071] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Accepted: 10/01/2021] [Indexed: 01/21/2023] Open
Abstract
Background High mobility group box 1 (HMGB1) causes microvascular endothelial cell barrier dysfunction during acute lung injury (ALI) in sepsis, but the mechanisms have not been well understood. We studied the roles of RAGE and Rho kinase 1 (ROCK1) in HMGB1-induced human pulmonary endothelial barrier disruption. Methods In the present study, the recombinant human high mobility group box 1 (rhHMGB1) was used to stimulate human pulmonary microvascular endothelial cells (HPMECs). The endothelial cell (EC) barrier permeability was examined by detecting FITC-dextran flux. CCK-8 assay was used to detect cell viability under rhHMGB1 treatments. The expression of related molecules involved in RhoA/ROCK1 pathway, phosphorylation of myosin light chain (MLC), F-actin, VE-cadherin and ZO-1 of different treated groups were measured by pull-down assay, western blot and immunofluorescence. Furthermore, we studied the effects of Rho kinase inhibitor (Y-27632), ROCK1/2 siRNA, RAGE-specific blocker (FPS-ZM1) and RAGE siRNA on endothelial barrier properties to elucidate the related mechanisms. Results In the present study, we demonstrated that rhHMGB1 induced EC barrier hyperpermeability in a dose-dependent and time-dependent manner by measuring FITC-dextran flux, a reflection of the loss of EC barrier integrity. Moreover, rhHMGB1 induced a dose-dependent and time-dependent increases in paracellular gap formation accompanied by the development of stress fiber rearrangement and disruption of VE-cadherin and ZO-1, a phenotypic change related to increased endothelial contractility and endothelial barrier permeability. Using inhibitors and siRNAs directed against RAGE and ROCK1/2, we systematically determined that RAGE mediated the rhHMGB1-induced stress fiber reorganization via RhoA/ROCK1 signaling activation and the subsequent MLC phosphorylation in ECs. Conclusion HMGB1 is capable of disrupting the endothelial barrier integrity. This study demonstrates that HMGB1 activates RhoA/ROCK1 pathway via RAGE, which phosphorylates MLC inducing stress fiber formation at short time, and HMGB1/RAGE reduces AJ/TJ expression at long term independently of RhoA/ROCK1 signaling pathway.
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Affiliation(s)
- Meng-Jiao Zhao
- Department of Critical Care Medicine, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Hao-Ran Jiang
- Department of Breast Oncology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Jing-Wen Sun
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, Shenyang, China
| | - Zi-Ang Wang
- Department of Critical Care Medicine, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Bo Hu
- Department of Critical Care Medicine, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Cheng-Rui Zhu
- Department of Critical Care Medicine, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Xiao-Han Yin
- Department of Critical Care Medicine, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Ming-Ming Chen
- Department of Critical Care Medicine, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Xiao-Chun Ma
- Department of Critical Care Medicine, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Wei-Dong Zhao
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, Shenyang, China
| | - Zheng-Gang Luan
- Department of Critical Care Medicine, The First Affiliated Hospital of China Medical University, Shenyang, China
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Shilpashree PS, Suresh KV, Sudhir RR, Srinivas SP. Automated Image Segmentation of the Corneal Endothelium in Patients With Fuchs Dystrophy. Transl Vis Sci Technol 2021; 10:27. [PMID: 34807254 PMCID: PMC8626858 DOI: 10.1167/tvst.10.13.27] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 09/19/2021] [Indexed: 11/24/2022] Open
Abstract
Purpose To perform segmentation of specular microscopy (SM) images of the corneal endothelium for comparing average perimeter length (APL) between Fuchs endothelial corneal dystrophy (FECD) patients and healthy subjects. Methods A retrospective review of clinical records of FECD patients and those with healthy endothelium was carried out to collect images of the endothelium. The images were segmented by modified U-Net, a deep learning architecture, followed by the Watershed algorithm to resolve merged cell borders (<5%). The segmented images were analyzed for endothelial cell density (ECDUW) and APL. Results The combination of the U-Net and Watershed algorithm, referred to as the UW approach, enabled a complete segmentation of the endothelium. In healthy, ECDUW was close to estimates by SM and manual segmentation (31 subjects; P > 0.1). However, in FECD, ECDUW was closer to estimates by manual segmentation but not by SM (27 patients; P < 0.001). ECDUW in FECD (2547 ± 499 cells/mm2; 60 patients) was smaller compared to that in the healthy (2713 ± 401 cells/mm2; 70 subjects) (P < 0.001). APL in the healthy was 66.87 ± 7.68 µm/cell (70 subjects), but it increased with %Guttae in FECD (56.60-195.30 µm/cell; 60 patients) (P < 0.0001). Conclusions The UW approach is precise for the segmentation of SM images from the healthy and FECD. Our analysis has revealed that APL increases with %Guttae. Translational Relevance The average perimeter length of the corneal endothelium, which represents the length of the paracellular pathway for fluid flux into the stroma, is increased in Fuchs dystrophy.
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Affiliation(s)
- Palanahalli S. Shilpashree
- Department of Electronics and Communication Engineering, Siddaganga Institute of Technology (Affiliated to Visvesvaraya Technological University, Belagavi), Tumkur, India
| | - Kaggere V. Suresh
- Department of Electronics and Communication Engineering, Siddaganga Institute of Technology (Affiliated to Visvesvaraya Technological University, Belagavi), Tumkur, India
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Chen SJ, Lin TB, Peng HY, Lin CH, Lee AS, Liu HJ, Li CC, Tseng KW. Protective Effects of Fucoxanthin Dampen Pathogen-Associated Molecular Pattern (PAMP) Lipopolysaccharide-Induced Inflammatory Action and Elevated Intraocular Pressure by Activating Nrf2 Signaling and Generating Reactive Oxygen Species. Antioxidants (Basel) 2021; 10:1092. [PMID: 34356327 PMCID: PMC8301160 DOI: 10.3390/antiox10071092] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/04/2021] [Accepted: 07/06/2021] [Indexed: 12/19/2022] Open
Abstract
Inflammation and oxidative stress are closely related processes in the pathogenesis of various ocular diseases. Uveitis is a disorder of the uvea and ocular tissues that causes extreme pain, decreases visual acuity, and can eventually lead to blindness. The pharmacological functions of fucoxanthin, isolated from brown algae, induce a variety of therapeutic effects such as oxidative stress reduction and repression of inflammation reactions. However, the specific anti-inflammatory effects of fucoxanthin on pathogen-associated molecular pattern (PAMP) lipopolysaccharide-induced uveitis have yet to be extensively described. Therefore, the aim of present study was to investigate the anti-inflammatory effects of fucoxanthin on uveitis in rats. The results showed that fucoxanthin effectively enhanced the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) in ocular tissues. Furthermore, fucoxanthin significantly increased the ocular activities of superoxide dismutase and decreased the levels of malondialdehyde stimulated by PAMP-induced uveitis. Ocular hypertension and the levels of inflammatory cells and proinflammatory cytokine tumor necrosis factor-alpha in the aqueous humor were alleviated with fucoxanthin treatment. Consequently, compared to the observed effects in lipopolysaccharide groups, fucoxanthin treatment significantly preserved iris sphincter innervation and pupillary function. Additionally, PAMP-induced corneal endothelial disruption was significantly inhibited by fucoxanthin treatment. Overall, these findings suggest that fucoxanthin may protect against inflammation from PAMP-induced uveitis by promoting the Nrf2 pathway and inhibiting oxidative stress.
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Affiliation(s)
- Shiu-Jau Chen
- Department of Neurosurgery, Mackay Memorial Hospital, Taipei 10449, Taiwan;
- Department of Medicine, Mackay Medical College, New Taipei 25245, Taiwan; (H.-Y.P.); (C.-H.L.); (A.-S.L.); (C.-C.L.)
| | - Tzer-Bin Lin
- Department of Physiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 11049, Taiwan;
| | - Hsien-Yu Peng
- Department of Medicine, Mackay Medical College, New Taipei 25245, Taiwan; (H.-Y.P.); (C.-H.L.); (A.-S.L.); (C.-C.L.)
| | - Cheng-Hsien Lin
- Department of Medicine, Mackay Medical College, New Taipei 25245, Taiwan; (H.-Y.P.); (C.-H.L.); (A.-S.L.); (C.-C.L.)
| | - An-Sheng Lee
- Department of Medicine, Mackay Medical College, New Taipei 25245, Taiwan; (H.-Y.P.); (C.-H.L.); (A.-S.L.); (C.-C.L.)
| | - Hsiang-Jui Liu
- Department of Optometry, MacKay Junior College of Medicine, Nursing, and Management, New Taipei 11260, Taiwan;
| | - Chun-Chieh Li
- Department of Medicine, Mackay Medical College, New Taipei 25245, Taiwan; (H.-Y.P.); (C.-H.L.); (A.-S.L.); (C.-C.L.)
| | - Kuang-Wen Tseng
- Department of Medicine, Mackay Medical College, New Taipei 25245, Taiwan; (H.-Y.P.); (C.-H.L.); (A.-S.L.); (C.-C.L.)
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Thanuja MY, Suma BS, Dinesh D, Ranganath SH, Srinivas SP. Microtubule Stabilization Protects Hypothermia-Induced Damage to the Cytoskeleton and Barrier Integrity of the Corneal Endothelial Cells. J Ocul Pharmacol Ther 2021; 37:399-411. [PMID: 34227869 DOI: 10.1089/jop.2021.0036] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Purpose: To determine the impact of hypothermia on the barrier function of donor corneal endothelium, thereby enhancing the success of corneal transplantation. Methods: Primary cultures of porcine endothelial cells were subjected to hypothermia (15 h; 4°C). The impact on microtubule assembly, peri-junctional actomyosin ring (PAMR), and ZO-1 was assessed by immunocytochemistry with and without pretreatment with a microtubule-stabilizing agent (Epothilone B; EpoB; 100 nM) and a p38 MAP kinase inhibitor (SB-203580; 20 μM). In addition, EpoB-loaded PLGA nanoparticles (ENPs) prepared by nanoprecipitation technique and coated with poly-L-lysine (PLL-ENPs) were administered one-time for sustained intracellular delivery of EpoB. Results: Exposure to hypothermia led to microtubule disassembly concomitant with the destruction of PAMR and the displacement of ZO-1 at the cellular periphery, suggesting a loss in barrier integrity. These adverse effects were attenuated by pretreatment with EpoB or SB-203580. PLL-ENPs possessed a zeta potential of ∼26 mV and a size of ∼110 nm. Drug loading and entrapment efficiency were 5% (w/w) and ∼87%, respectively, and PLL-ENPs showed a biphasic release in vitro: burst phase (1 day), followed by a sustained phase (∼4 weeks). Pretreatment with PLL-ENPs (0.4 mg/mL) for 24 h stabilized the microtubules and opposed the hypothermia-induced damage to PAMR and the redistribution of ZO-1. Conclusions: Hypothermia induces microtubule disassembly via activation of p38 MAP kinase and subsequently breaks down the barrier function of the endothelium. Sustained intracellular delivery of EpoB using nanoparticles has the potential to overcome endothelial barrier failure during prolonged cold storage of donor cornea.
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Affiliation(s)
- Marasarakottige Y Thanuja
- Bio-INvENT Lab, Department of Chemical Engineering, Siddaganga Institute of Technology, Tumakuru, India
| | - Bangalore S Suma
- Bioimaging Facility, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
| | - Divyasree Dinesh
- Department of Biotechnology, Siddaganga Institute of Technology, Tumakuru, India
| | - Sudhir H Ranganath
- Bio-INvENT Lab, Department of Chemical Engineering, Siddaganga Institute of Technology, Tumakuru, India
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Price MO, Price FW. Randomized, Double-Masked, Pilot Study of Netarsudil 0.02% Ophthalmic Solution for Treatment of Corneal Edema in Fuchs Dystrophy. Am J Ophthalmol 2021; 227:100-105. [PMID: 33737034 DOI: 10.1016/j.ajo.2021.03.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 10/20/2020] [Accepted: 03/05/2021] [Indexed: 01/08/2023]
Abstract
PURPOSE To evaluate off-label use of netarsudil 0.02% for treatment of corneal edema associated with Fuchs dystrophy. DESIGN Prospective, randomized clinical trial. METHODS Twenty-nine subjects with symptomatic Fuchs dystrophy were enrolled and randomized to use netarsudil or placebo eye drops once daily for 3 months. The primary outcomes were the change in central corneal thickness between baseline and 1 month and between baseline and 3 months. Secondary outcomes included change in scotopic corrected distance visual acuity (CDVA) at 3 months and change in scores on a visual disability questionnaire validated for use with Fuchs dystrophy. RESULTS Compared with use of placebo, use of netarsudil produced significant reduction in central corneal thickness at 1 month (mean difference, -20 µm; 95% confidence interval, -32 to -9 µm) and 3 months (mean difference, -26 µm; 95% confidence interval, -39 to -12 µm) and significant improvement in scotopic CDVA at 3 months (mean difference +1.6 lines; 95% confidence interval, 0.2-3.0 lines). Scores on the visual disability questionnaire did not change significantly in either arm or differ significantly between arms. One subject assigned to netarsudil had baseline epithelial bullae and withdrew from the study because of disabling glare. CONCLUSIONS Use of netarsudil was associated with reduction of corneal edema and improvement in scotopic CDVA in Fuchs dystrophy patients. Further study is needed to more fully assess patient satisfaction and visual acuity under various lighting conditions and to compare use of netarsudil with other treatment options such as endothelial keratoplasty.
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Incorporating Differential Gene Expression Analysis with Predictive Biomarkers to Identify Novel Therapeutic Drugs for Fuchs Endothelial Corneal Dystrophy. J Ophthalmol 2021; 2021:5580595. [PMID: 34258047 PMCID: PMC8260298 DOI: 10.1155/2021/5580595] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 05/15/2021] [Accepted: 06/17/2021] [Indexed: 11/24/2022] Open
Abstract
Purpose Based on the differential gene expression analysis for predictive biomarkers with RNA-Sequencing data from Fuchs endothelial corneal dystrophy (FECD) patients, we are aiming to evaluate the efficacy of Library of Integrated Network-based Cellular Signatures (LINCS) perturbagen prediction software to identify novel pharmacotherapeutic targets that can revert the pathogenic gene expression signatures and reverse disease phenotype in FECD. Methods A publicly available RNA-seq dataset was used to compare corneal endothelial specimens from controls and patients with FECD. Based on the differential gene expression analysis for predictive biomarkers, we evaluated the efficacy of LINCS perturbagen prediction software to identify novel therapeutic targets that can revert the pathogenic gene expression signatures and reverse disease phenotypes in FECD. Results The RNA-seq dataset of the corneal endothelial cells from FECD patients revealed the differential gene expression signatures of FECD. Many of the differential expressed genes are related to canonical pathways of the FECD pathogenesis, such as extracellular matrix reorganization and immunological response. The expression levels of genes VSIG2, IL18, and ITGB8 were significantly increased in FECD compared with control. Meanwhile, the expression levels of CNGA3, SMOX, and CERS1 were significantly lower in the FECD than in control. We employed LINCS L1000 Characteristic Direction Signature Search Engine (L1000-CDS2) to investigate pathway-based molecular treatment. L1000-CDS2 predicted that small molecule drugs such as histone deacetylase (HDAC) inhibitors might be a potential candidate to reverse the pathological gene expression signature in FECD. Conclusions Based on differential gene expression signatures, several candidate drugs have been identified to reverse the disease phenotypes in FECD. Gene expression signature with LINCS small molecule prediction software can discover novel preclinical drug candidates for FECD.
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Jung B, Lee H, Kim S, Tchah H, Hwang C. Effect of Rho-Associated Kinase Inhibitor and Mesenchymal Stem Cell-Derived Conditioned Medium on Corneal Endothelial Cell Senescence and Proliferation. Cells 2021; 10:cells10061463. [PMID: 34207965 PMCID: PMC8230597 DOI: 10.3390/cells10061463] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 06/02/2021] [Accepted: 06/06/2021] [Indexed: 12/13/2022] Open
Abstract
This study aims to obtain sufficient corneal endothelial cells for regenerative application. We examined the combinatory effects of Rho-associated kinase (ROCK) inhibitor Y-27632 and mesenchymal stem cell-derived conditioned medium (MSC-CM) on the proliferation and senescence of rabbit corneal endothelial cells (rCECs). rCECs were cultured in a control medium, a control medium mixed with either Y-27632 or MSC-CM, and a combinatory medium containing Y-27632 and MSC-CM. Cells were analyzed for morphology, cell size, nuclei/cytoplasmic ratio, proliferation capacity and gene expression. rCECs cultured in a combinatory culture medium showed a higher passage number, cell proliferation, and low senescence. rCECs on collagen type I film showed high expression of tight junction. The cell proliferation marker Ki-67 was positively stained either in Y-27632 or MSC-CM-containing media. Genes related to cell proliferation resulted in negligible changes in MKI67, CIP2A, and PCNA in the combinatory medium, suggesting proliferative capacity was maintained. In contrast, all of these genes were significantly downregulated in the other groups. Senescence marker β-galactosidase-positive cells significantly decreased in either MSC-CM and/or Y-27632 mixed media. Senescence-related genes downregulated LMNB1 and MAP2K6, and upregulated MMP2. Cell cycle checkpoint genes such as CDC25C, CDCA2, and CIP2A did not vary in the combinatory medium but were significantly downregulated in either ROCK inhibitor or MSC-CM alone. These results imply the synergistic effect of combinatory culture medium on corneal endothelial cell proliferation and high cell number. This study supports high potential for translation to the development of human corneal endothelial tissue regeneration.
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Affiliation(s)
- Boyoung Jung
- Department of Convergence Medicine, University of Ulsan College of Medicine, Seoul 05505, Korea;
- Biomedical Engineering Research Center, Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, Korea;
| | - Hun Lee
- Department of Ophthalmology, University of Ulsan College of Medicine, Seoul 05505, Korea;
- Department of Ophthalmology, Asan Medical Center, Seoul 05505, Korea
| | - Sumi Kim
- Biomedical Engineering Research Center, Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, Korea;
| | - Hungwon Tchah
- Department of Ophthalmology, University of Ulsan College of Medicine, Seoul 05505, Korea;
- Department of Ophthalmology, Asan Medical Center, Seoul 05505, Korea
- Correspondence: (H.T.); (C.H.); Tel.: +82-2-3010-3674 (H.T.); +82-2-3010-4097 (C.H.); Fax: +82-2-470-6640 (H.T.); +82-2-3010-4182 (C.H.)
| | - Changmo Hwang
- Department of Convergence Medicine, University of Ulsan College of Medicine, Seoul 05505, Korea;
- Biomedical Engineering Research Center, Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, Korea;
- Correspondence: (H.T.); (C.H.); Tel.: +82-2-3010-3674 (H.T.); +82-2-3010-4097 (C.H.); Fax: +82-2-470-6640 (H.T.); +82-2-3010-4182 (C.H.)
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Geoffrion D, Robert MC, Di Polo A, Koenekoop RK, Agoumi Y, Harissi-Dagher M. Tear Film Cytokine Profile of Patients With the Boston Keratoprosthesis Type 1: Comparing Patients With and Without Glaucoma. Invest Ophthalmol Vis Sci 2021; 62:20. [PMID: 33856415 PMCID: PMC8054627 DOI: 10.1167/iovs.62.4.20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Purpose Inflammatory cytokines are involved in glaucoma pathogenesis. The purpose is to compare cytokine levels in the tear film of Boston keratoprosthesis (KPro) patients with and without glaucoma, relative to controls, and correlate levels with clinical parameters. Methods This cross-sectional study enrolled 58 eyes (58 patients): 41 KPro eyes with glaucoma, 7 KPro eyes without glaucoma, and 10 healthy controls. Twenty-seven cytokines were measured by multiplex bead immunoassay. Intraocular pressure (IOP), cup-to-disk ratio (CDR), retinal nerve fiber layer, visual acuity, topical medications, and angle closure were assessed in all KPro eyes. Cytokine levels between groups were analyzed by nonparametric tests, and correlations with clinical parameters by Spearman's test. Results Levels of TNF-ɑ, IL-1β, FGF-basic, and IFN-ɣ were significantly higher in KPro with glaucoma compared to KPro without (P = 0.020; 0.008; 0.043; 0.018, respectively). KPro groups had similar characteristics and topical antibiotic/steroid regimen. Levels of IL-1Ra, IL-15, VEGF, and RANTES were significantly higher in KPro with glaucoma compared to controls (P < 0.001; = 0.034; < 0.001; = 0.001, respectively). IL-1β and IFN-ɣ levels were positively correlated with CDR (r = 0.309, P = 0.039 and r = 0.452, P = 0.006, respectively) and IOP (r = 0.292, P = 0.047 and r = 0.368, P = 0.023, respectively). TNF-α and FGF-basic levels were positively correlated with CDR (r = 0.348, P = 0.022 and r = 0.344, P = 0.021, respectively). Conclusions TNF-α, IL-1β, FGF-basic, IFN-ɣ are elevated in tears of KPro patients with glaucoma and correlate with CDR and IOP. These results show, for the first time in humans, concordance with documented elevations of TNF-α and IL-1β in the murine KPro model. Ocular surface inflammation may reflect inflammatory processes of KPro glaucoma.
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Affiliation(s)
- Dominique Geoffrion
- Department of Ophthalmology, Université de Montréal, Centre hospitalier de l'Université de Montréal, Montreal, Quebec, Canada.,Department of Experimental Surgery, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Marie-Claude Robert
- Department of Ophthalmology, Université de Montréal, Centre hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
| | - Adriana Di Polo
- Department of Ophthalmology, Université de Montréal, Centre hospitalier de l'Université de Montréal, Montreal, Quebec, Canada.,Department of Neurosciences, Université de Montréal, Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada
| | - Robert K Koenekoop
- Departments of Experimental Surgery, Paediatric Surgery, Adult Ophthalmology, and Human Genetics, Montreal Children's Hospital, McGill University Health Centre, McGill University, Montreal, Quebec, Canada
| | - Younes Agoumi
- Department of Ophthalmology, Université de Montréal, Centre hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
| | - Mona Harissi-Dagher
- Department of Ophthalmology, Université de Montréal, Centre hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
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Current development of alternative treatments for endothelial decompensation: Cell-based therapy. Exp Eye Res 2021; 207:108560. [PMID: 33811914 DOI: 10.1016/j.exer.2021.108560] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 03/03/2021] [Accepted: 03/22/2021] [Indexed: 12/13/2022]
Abstract
Current treatment for corneal endothelial dysfunction consists in the replacement of corneal endothelium by keratoplasty. Owing to the scarcity of donor corneas and the increasing number of transplants, alternative treatments such as cell-based therapies are necessary. In this article, we highlight the biological aspects of the cornea and the corneal endothelium, as well as the context that surrounds the need for new alternatives to conventional keratoplasty. We then review some of those experimental treatments in more detail, focusing on the development of the in vitro and preclinical phases of two cell-based therapies: tissue-engineered endothelial keratoplasty (TE-EK) and cell injection. In the case of TE-EK graft construction, we analyse the current progress, considering all the requirements it must meet in order to be functional. Moreover, we discuss the inherent drawbacks of endothelial keratoplasties, which TE-EK grafts should overcome in order to make surgical intervention easier and to improve the outcomes of current endothelial keratoplasties. Finally, we analyse the development of preclinical trials and their limitations in terms of performing an optimal functional evaluation of cell-based therapy, and we conclude by discussing early clinical trials in humans.
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Igarashi N, Honjo M, Kaburaki T, Aihara M. Effects of ROCK Inhibitors on Apoptosis of Corneal Endothelial Cells in CMV-Positive Posner-Schlossman Syndrome Patients. Invest Ophthalmol Vis Sci 2021; 61:5. [PMID: 32749463 PMCID: PMC7441372 DOI: 10.1167/iovs.61.10.5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Purpose To examine the role of aqueous tumor necrosis factor α (TNF-α)–RhoA–Rho kinase (ROCK) signaling in cytomegalovirus (CMV)-induced apoptosis and the barrier function of cultured human corneal endothelial cells (hCECs) in CMV-positive Posner–Schlossman syndrome (CMV+/PSS) patients. Methods Aqueous levels of TNF-α, IL-8, IL-10, and several other cytokines in 19 CMV+/PSS patients and 20 healthy control subjects were quantitated using a multiplex assay. The expression of active RhoA in hCECs post-CMV infection was determined using western blotting (WB). The expression levels of TNF-α and nuclear factor kappa B (NF-κB) in CMV-infected hCECs were examined by immunocytochemistry (ICC) and WB with and without ROCK inhibitors. The apoptotic rate and barrier integrity in CMV-infected hCECs were also examined. Results The expression levels of TNF-α, monocyte chemoattractant protein-1 (MCP-1), IL-8, and IL-10 were upregulated in the aqueous humor of CMV+/PSS patients, and among these upregulated cytokines aqueous TNF-α was negatively correlated with the number of corneal endothelial cells. In CMV-infected hCECs, upregulation of TNF-α and NF-κB was determined by WB and ICC. In hCECs, CMV infection induced apoptosis and significantly impaired cell–cell contacts, effects that were attenuated by treatment with a ROCK inhibitor. Conclusions Aqueous TNF-α was upregulated in CMV+/PSS patients, which may have triggered corneal endothelial cell loss. Modulation of TNF-α, including its downstream Rho–ROCK signaling, could serve as a novel treatment modality for corneal endothelial cell loss in CMV+/PSS patients.
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Correlations between tear fluid and aqueous humor cytokine levels in bullous keratopathy. Ocul Surf 2020; 18:801-807. [PMID: 32735951 DOI: 10.1016/j.jtos.2020.06.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 05/12/2020] [Accepted: 06/29/2020] [Indexed: 01/24/2023]
Abstract
PURPOSE To evaluate the correlation between tear fluid and aqueous humor (AqH) cytokine levels in eyes with bullous keratopathy (BK) and with normal endothelium. METHODS This prospective consecutive case-series study included 71 eyes of 71 patients: 31 eyes with BK, 18 eyes with non-BK corneal diseases, and 22 eyes with uncomplicated cataract (healthy controls). Total protein and cytokine (interleukin [IL]-1α, IL-1β, IL-4, IL-6, IL-8, IL-10, MIP-1α, MIP-1β, monocyte chemotactic protein [MCP]-1, E-selectin, P-selectin, soluble intercellular adhesion molecule [sICAM]-1, and IP-10) levels in the tear fluid and AqH were measured using multiplex beads immunoassay. The correlations between tear and AqH cytokine levels were assessed. RESULTS The AqH protein level was significantly higher in BK eyes (1.09 ± 0.08 mg/mL) than in non-BK (0.63 ± 0.11, P = 0.0004) and healthy control (0.62 ± 0.06, P = 0.0002) eyes. The tear total protein and IL-4 levels were significantly higher in the BK group compared to healthy controls (P = 0.0374 and 0.0032, respectively). The AqH IL-8 and sICAM-1 levels were significantly higher in the BK group compared to controls (P = 0.0001 and 0.0083, respectively). In BK eyes, the tear IL-4 level was significantly correlated with the MCP-1(r = 0.563, P = 0.001) and total protein (r = 0.589, P = 0.001) AqH levels. The tear IL-8 level was significantly correlated with the MCP-1(r = 0.598, p = 0.001) and IL-4 (r = 0.781, p < 0.0001) AqH levels in BK eyes. However, no significant correlations were found between tear and AqH cytokine levels in non-BK and healthy controls eyes. CONCLUSIONS The tear cytokine levels are correlated with those of AqH only in BK, but not in non-BK and healthy controls.
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Ho WT, Chang JS, Chou SF, Hwang WL, Shih PJ, Chang SW, Yang MH, Jou TS, Wang IJ. Targeting non-muscle myosin II promotes corneal endothelial migration through regulating lamellipodial dynamics. J Mol Med (Berl) 2019; 97:1345-1357. [PMID: 31302714 DOI: 10.1007/s00109-019-01818-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 05/18/2019] [Accepted: 07/02/2019] [Indexed: 10/26/2022]
Abstract
Corneal endothelial cell (CEC) dysfunction causes corneal edema that may lead to blindness. In addition to corneal transplantation, simple descemetorhexis has been proposed to treat centrally located disease with adequate peripheral cell reserve, but promoting the centripetal migration of CECs is pivotal to this strategy. Here, we show that targeting non-muscle myosin II (NMII) activity by Y27632, a ROCK inhibitor, or blebbistatin, a selective NMII inhibitor, promotes directional migration of CECs and accelerates in vitro wound healing. The lamellipodial protrusion persistence is increased, and actin retrograde flow is decreased after NMII inhibition. Counteracting lamellipodial protrusion by actin-related protein 2/3 (ARP2/3) inhibitor abolishes this migration-promoting effect. Although both Y27632 and blebbistatin accelerate wound healing, cell junctional integrity and barrier function are better preserved after blebbistatin treatment, leading to more rapid corneal deturgescence in rabbit corneal endothelial wounding model. Our findings indicate that NMII is a promising therapeutic target in the treatment of CEC dysfunction. KEY MESSAGES: NMII inhibition promotes directional migration and wound healing of CECs in vitro. Lamellipodial protrusion persistence is increased after NMII inhibition. Selective NMII inhibitor preserves junctional integrity better than ROCK inhibitor. Selective NMII inhibitor accelerates corneal deturgescence after wounding in vivo.
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Affiliation(s)
- Wei-Ting Ho
- Department of Ophthalmology, Far Eastern Memorial Hospital, New Taipei City, Taiwan.,Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Jung-Shen Chang
- Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan
| | - San-Fang Chou
- Department of Medical Research, Far Eastern Memorial Hospital, New Taipei City, Taiwan
| | - Wei-Lun Hwang
- Department of Biotechnology and Laboratory Science in Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Po-Jen Shih
- Department of Civil and Environmental Engineering, National University of Kaohsiung, Kaohsiung, Taiwan
| | - Shu-Wen Chang
- Department of Ophthalmology, Far Eastern Memorial Hospital, New Taipei City, Taiwan.,College of Medicine, National Taiwan University, No. 7, Chung-Shan S. Rd., Taipei, Taiwan
| | - Muh-Hwa Yang
- Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.,Division of Medical Oncology, Department of Oncology, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Tzuu-Shuh Jou
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan. .,College of Medicine, National Taiwan University, No. 7, Chung-Shan S. Rd., Taipei, Taiwan. .,Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan.
| | - I-Jong Wang
- Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan. .,College of Medicine, National Taiwan University, No. 7, Chung-Shan S. Rd., Taipei, Taiwan.
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Zhu Q, Zhu Y, Tighe S, Liu Y, Hu M. Engineering of Human Corneal Endothelial Cells In Vitro. Int J Med Sci 2019; 16:507-512. [PMID: 31171901 PMCID: PMC6535652 DOI: 10.7150/ijms.30759] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 01/10/2019] [Indexed: 12/13/2022] Open
Abstract
Human corneal endothelial cells are responsible for controlling corneal transparency, however they are notorious for their limited proliferative capability. Thus, damage to these cells may cause irreversible blindness. Currently, the only way to cure blindness caused by corneal endothelial dysfunction is via corneal transplantation of a cadaver donor cornea with healthy corneal endothelium. Due to severe shortage of donor corneas worldwide, it has become paramount to develop human corneal endothelial grafts in vitro that can subsequently be transplanted in humans. Recently, we have reported effective expansion of human corneal endothelial cells by reprogramming the cells into progenitor status through use of p120-Kaiso siRNA knockdown. This new reprogramming approach circumvents the need of using induced pluripotent stem cells or embryonic stem cells. Successful promotion of this technology will encourage scientists to re-think how "contact inhibition" can safely be perturbed to our benefit, i.e., effective engineering of an in vivo-like tissue while successful maintaining the normal phenotype. In this review, we present current advances in reprogramming corneal endothelial cells in vitro, detail the methods to successful engineer human corneal endothelial grafts, and discuss their future clinical applications to cure corneal blindness.
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Affiliation(s)
- Qin Zhu
- Department of Ophthalmology, The Second People's Hospital of Yunnan Province (Fourth Affiliated Hospital of Kunming Medical University); Yunnan Eye Institute; Key Laboratory of Yunnan Province for the Prevention and Treatment of ophthalmology (2017DG008); Provincial Innovation Team for Cataract and Ocular Fundus Disease (2017HC010); Expert Workstation of Yao Ke (2017IC064), Kunming, 650021 China
| | - Yingting Zhu
- Tissue Tech, Inc., Ocular Surface Center, and Ocular Surface Research & Education Foundation, Miami, FL, 33173 USA
| | - Sean Tighe
- Tissue Tech, Inc., Ocular Surface Center, and Ocular Surface Research & Education Foundation, Miami, FL, 33173 USA
| | - Yongsong Liu
- Department of Ophthalmology, Yan' An Hospital of Kunming City, Kunming, 650051, China
| | - Min Hu
- Department of Ophthalmology, The Second People's Hospital of Yunnan Province (Fourth Affiliated Hospital of Kunming Medical University); Yunnan Eye Institute; Key Laboratory of Yunnan Province for the Prevention and Treatment of ophthalmology (2017DG008); Provincial Innovation Team for Cataract and Ocular Fundus Disease (2017HC010); Expert Workstation of Yao Ke (2017IC064), Kunming, 650021 China
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Ng CT, Fong LY, Yong YK, Hakim MN, Ahmad Z. Interferon-γ induces biphasic changes in caldesmon localization as well as adherens junction organization and expression in HUVECs. Cytokine 2018; 111:541-550. [PMID: 29909980 DOI: 10.1016/j.cyto.2018.06.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 06/06/2018] [Accepted: 06/08/2018] [Indexed: 01/11/2023]
Abstract
Endothelial barrier dysfunction leads to increased endothelial permeability and is an early step in the development of vascular inflammatory diseases such as atherosclerosis. Interferon-γ (IFN-γ), a proinflammatory cytokine, is known to cause increased endothelial permeability. However, the mechanisms by which IFN-γ disrupts the endothelial barrier have not been clarified. This study aimed to investigate how IFN-γ impairs the endothelial barrier integrity by specifically examining the roles of caldesmon, adherens junctions (AJs) and p38 mitogen-activated protein (MAP) kinase in IFN-γ-induced endothelial barrier dysfunction. IFN-γ exhibited a biphasic effect on caldesmon localization and both the structural organization and protein expression of AJs. In the early phase (4-8 h), IFN-γ induced the formation of peripheral caldesmon bands and discontinuous AJs, while AJ protein expression was unchanged. Interestingly, IFN-γ also stimulated caldesmon phosphorylation, resulting in actin dissociation from caldesmon at 8 h. Conversely, changes seen in the late phase (16-24 h) included cytoplasmic caldesmon dispersal, AJ linearization and junctional area reduction, which were associated with reduced membrane, cytoskeletal and total AJ protein expression. In addition, IFN-γ enhanced myosin binding to caldesmon at 12 h and persisted up to 24 h. Furthermore, inhibition of p38 MAP kinase by SB203580 did not reverse either the early or late phase changes observed. These data suggest that IFN-γ may activate signaling molecules other than p38 MAP kinase. In conclusion, our findings enhance the current understanding of how IFN-γ disrupts endothelial barrier function and reveal potential therapeutic targets, such as caldesmon and AJs, for the treatment of IFN-γ-associated vascular inflammatory diseases.
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Affiliation(s)
- Chin Theng Ng
- Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Physiology Unit, Faculty of Medicine, AIMST University, 08100 Bedong, Kedah, Malaysia.
| | - Lai Yen Fong
- Department of Pre-clinical Sciences, Faculty of Medicine and Health Sciences, Universiti Tunku Abdul Rahman, 43000 Kajang, Selangor, Malaysia.
| | - Yoke Keong Yong
- Department of Human Anatomy, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - Muhammad Nazrul Hakim
- Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - Zuraini Ahmad
- Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
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Function-Related Protein Expression in Fuchs Endothelial Corneal Dystrophy Cells and Tissue Models. THE AMERICAN JOURNAL OF PATHOLOGY 2018; 188:1703-1712. [PMID: 29698634 DOI: 10.1016/j.ajpath.2018.03.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 03/26/2018] [Accepted: 03/30/2018] [Indexed: 12/13/2022]
Abstract
Fuchs endothelial corneal dystrophy (FECD) is a corneal pathology that affects the endothelial cell's ability to maintain deturgescence, resulting in a progressive loss of corneal transparency. In this study, we investigated the expression of function-related proteins in corneal endothelial cells using FECD or healthy corneal endothelial cells, either in a cell culture two-dimensional model or in an engineered corneal endothelium three-dimensional tissue model. No statistically significant difference in gene regulation was observed for the function-related families ATP1, SLC4, SLC16, AQP, TJP, and CDH between the FECD and the healthy cell models. Similarly, no difference in barrier integrity (transendothelial electrical resistance measurements and permeability assays) was observed in vitro between FECD and healthy cultured cells. Protein expression of the key function-related families was decreased for Na+/K+-ATPase α1 subunit, monocarboxylate transporters 1 and 4 in native ex vivo end-stage FECD specimens, whereas it returned to levels comparable to that of healthy tissues in the engineered FECD model. These results indicate that cell expansion and tissue engineering culture conditions can generate a corneal endothelium from pathologic FECD cells, with levels of function-related proteins similar to that of healthy tissues. Overall, these results explain why it is possible to reform a functional endothelium using corneal endothelial cells isolated from nonfunctional FECD pathologic specimens.
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Liskova P, Dudakova L, Evans CJ, Rojas Lopez KE, Pontikos N, Athanasiou D, Jama H, Sach J, Skalicka P, Stranecky V, Kmoch S, Thaung C, Filipec M, Cheetham ME, Davidson AE, Tuft SJ, Hardcastle AJ. Ectopic GRHL2 Expression Due to Non-coding Mutations Promotes Cell State Transition and Causes Posterior Polymorphous Corneal Dystrophy 4. Am J Hum Genet 2018; 102:447-459. [PMID: 29499165 PMCID: PMC5985340 DOI: 10.1016/j.ajhg.2018.02.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 02/02/2018] [Indexed: 12/11/2022] Open
Abstract
In a large family of Czech origin, we mapped a locus for an autosomal-dominant corneal endothelial dystrophy, posterior polymorphous corneal dystrophy 4 (PPCD4), to 8q22.3-q24.12. Whole-genome sequencing identified a unique variant (c.20+544G>T) in this locus, within an intronic regulatory region of GRHL2. Targeted sequencing identified the same variant in three additional previously unsolved PPCD-affected families, including a de novo occurrence that suggests this is a recurrent mutation. Two further unique variants were identified in intron 1 of GRHL2 (c.20+257delT and c.20+133delA) in unrelated PPCD-affected families. GRHL2 is a transcription factor that suppresses epithelial-to-mesenchymal transition (EMT) and is a direct transcriptional repressor of ZEB1. ZEB1 mutations leading to haploinsufficiency cause PPCD3. We previously identified promoter mutations in OVOL2, a gene not normally expressed in the corneal endothelium, as the cause of PPCD1. OVOL2 drives mesenchymal-to-epithelial transition (MET) by directly inhibiting EMT-inducing transcription factors, such as ZEB1. Here, we demonstrate that the GRHL2 regulatory variants identified in PPCD4-affected individuals induce increased transcriptional activity in vitro. Furthermore, although GRHL2 is not expressed in corneal endothelial cells in control tissue, we detected GRHL2 in the corneal "endothelium" in PPCD4 tissue. These cells were also positive for epithelial markers E-Cadherin and Cytokeratin 7, indicating they have transitioned to an epithelial-like cell type. We suggest that mutations inducing MET within the corneal endothelium are a convergent pathogenic mechanism leading to dysfunction of the endothelial barrier and disease.
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Affiliation(s)
- Petra Liskova
- Research Unit for Rare Diseases, Department of Paediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, Ke Karlovu 2, Prague 128 08, Czech Republic; Department of Ophthalmology, First Faculty of Medicine, Charles University and General University Hospital in Prague, U Nemocnice 2, Prague 128 08, Czech Republic; UCL Institute of Ophthalmology, University College London, London EC1V 9EL, UK.
| | - Lubica Dudakova
- Research Unit for Rare Diseases, Department of Paediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, Ke Karlovu 2, Prague 128 08, Czech Republic
| | - Cerys J Evans
- UCL Institute of Ophthalmology, University College London, London EC1V 9EL, UK
| | - Karla E Rojas Lopez
- UCL Institute of Ophthalmology, University College London, London EC1V 9EL, UK
| | - Nikolas Pontikos
- UCL Institute of Ophthalmology, University College London, London EC1V 9EL, UK
| | - Dimitra Athanasiou
- UCL Institute of Ophthalmology, University College London, London EC1V 9EL, UK
| | - Hodan Jama
- UCL Institute of Ophthalmology, University College London, London EC1V 9EL, UK
| | - Josef Sach
- Institute of Pathology, Third Faculty of Medicine, Charles University, Faculty Hospital Kralovske Vinohrady, Srobarova 50, Prague 100 34, Czech Republic
| | - Pavlina Skalicka
- Research Unit for Rare Diseases, Department of Paediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, Ke Karlovu 2, Prague 128 08, Czech Republic; Department of Ophthalmology, First Faculty of Medicine, Charles University and General University Hospital in Prague, U Nemocnice 2, Prague 128 08, Czech Republic
| | - Viktor Stranecky
- Research Unit for Rare Diseases, Department of Paediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, Ke Karlovu 2, Prague 128 08, Czech Republic
| | - Stanislav Kmoch
- Research Unit for Rare Diseases, Department of Paediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, Ke Karlovu 2, Prague 128 08, Czech Republic
| | - Caroline Thaung
- UCL Institute of Ophthalmology, University College London, London EC1V 9EL, UK; Moorfields Eye Hospital, London EC1V 2PD, UK
| | - Martin Filipec
- Department of Ophthalmology, First Faculty of Medicine, Charles University and General University Hospital in Prague, U Nemocnice 2, Prague 128 08, Czech Republic
| | - Michael E Cheetham
- UCL Institute of Ophthalmology, University College London, London EC1V 9EL, UK
| | - Alice E Davidson
- UCL Institute of Ophthalmology, University College London, London EC1V 9EL, UK
| | | | - Alison J Hardcastle
- UCL Institute of Ophthalmology, University College London, London EC1V 9EL, UK; Moorfields Eye Hospital, London EC1V 2PD, UK.
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Marquez-Curtis LA, McGann LE, Elliott JAW. Expansion and cryopreservation of porcine and human corneal endothelial cells. Cryobiology 2017; 77:1-13. [PMID: 28465186 DOI: 10.1016/j.cryobiol.2017.04.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 04/27/2017] [Accepted: 04/28/2017] [Indexed: 12/13/2022]
Abstract
Impairment of the corneal endothelium causes blindness that afflicts millions worldwide and constitutes the most often cited indication for corneal transplants. The scarcity of donor corneas has prompted the alternative use of tissue-engineered grafts which requires the ex vivo expansion and cryopreservation of corneal endothelial cells. The aims of this study are to culture and identify the conditions that will yield viable and functional corneal endothelial cells after cryopreservation. Previously, using human umbilical vein endothelial cells (HUVECs), we employed a systematic approach to optimize the post-thaw recovery of cells with high membrane integrity and functionality. Here, we investigated whether improved protocols for HUVECs translate to the cryopreservation of corneal endothelial cells, despite the differences in function and embryonic origin of these cell types. First, we isolated endothelial cells from pig corneas and then applied an interrupted slow cooling protocol in the presence of dimethyl sulfoxide (Me2SO), with or without hydroxyethyl starch (HES). Next, we isolated and expanded endothelial cells from human corneas and applied the best protocol verified using porcine cells. We found that slow cooling at 1 °C/min in the presence of 5% Me2SO and 6% HES, followed by rapid thawing after liquid nitrogen storage, yields membrane-intact cells that could form monolayers expressing the tight junction marker ZO-1 and cytoskeleton F-actin, and could form tubes in reconstituted basement membrane matrix. Thus, we show that a cryopreservation protocol optimized for HUVECs can be applied successfully to corneal endothelial cells, and this could provide a means to address the need for off-the-shelf cryopreserved cells for corneal tissue engineering and regenerative medicine.
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Affiliation(s)
- Leah A Marquez-Curtis
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta, Canada; Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, Canada.
| | - Locksley E McGann
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, Canada.
| | - Janet A W Elliott
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta, Canada; Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, Canada.
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Santander-García D, Ortega MC, Benito-Martínez S, Barroso S, Jiménez-Alfaro I, Millán J. A human cellular system for analyzing signaling during corneal endothelial barrier dysfunction. Exp Eye Res 2016; 153:8-13. [PMID: 27697549 DOI: 10.1016/j.exer.2016.09.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 08/25/2016] [Accepted: 09/30/2016] [Indexed: 02/07/2023]
Abstract
Correct corneal endothelial barrier function is essential for maintaining corneal transparency. However, research on cell signaling pathways mediating corneal endothelial barrier dysfunction has progressed more slowly than that involving other cellular barriers because of the lack of human corneal endothelial cell models. Here we have optimized the culture of the human corneal endothelial cell (HCEC) line B4G12 as a model for studying paracellular permeability. We show that B4G12-HCECs form confluent monolayers with stable cell-cell junctions when cultured on plastic, but not glass, surfaces precoated with various extracellular matrix components. Cell morphometry and measuring intercellular spaces and transendothelial electric resistance indicate that B4G12-HCECs form optimal monolayers on collagen and fibronectin. Based on the use of specific inhibitors, it has been proposed that the Rho-regulated kinases, ROCK-I and ROCK-II, mediate actomyosin-induced contraction in corneal endothelial cell barriers. ROCKs are effectors of RhoA, RhoB and RhoC. We show that the GTPase RhoA and its effector ROCK-II are predominantly expressed in B4G12-HCECs and primary human corneal endothelial cells. The activation of Rho GTPases during acute barrier disruption has not been investigated in corneal endothelial cells. RhoA, but not other related GTPases that are highly expressed in B4G12-HCECs, such as Rac1 and Cdc42, is transiently activated during barrier disruption in response to the inflammatory mediator thrombin. Pharmacological inhibition of RhoA and ROCK reduces B4G12-HCEC acute contraction. We propose that exploiting B4G12-HCECs is a useful experimental strategy for gaining further insight into the signaling pathways involved in human corneal endothelial barrier function.
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Affiliation(s)
- Diana Santander-García
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Madrid, Spain; Department of Ophthalmology, Hospital Universitario Rey Juan Carlos, Mostoles, Spain; Department of Ophthalmology, Fundación Jiménez Díaz, Madrid, Spain; Instituto de Investigación Sanitaria, Fundación Jiménez Díaz, Madrid, Spain
| | | | | | - Susana Barroso
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Madrid, Spain
| | - Ignacio Jiménez-Alfaro
- Department of Ophthalmology, Fundación Jiménez Díaz, Madrid, Spain; Instituto de Investigación Sanitaria, Fundación Jiménez Díaz, Madrid, Spain
| | - Jaime Millán
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Madrid, Spain.
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Ali M, Raghunathan V, Li JY, Murphy CJ, Thomasy SM. Biomechanical relationships between the corneal endothelium and Descemet's membrane. Exp Eye Res 2016; 152:57-70. [PMID: 27639516 DOI: 10.1016/j.exer.2016.09.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 09/13/2016] [Indexed: 12/28/2022]
Abstract
The posterior face of the cornea consists of the corneal endothelium, a monolayer of cuboidal cells that secrete and attach to Descemet's membrane, an exaggerated basement membrane. Dysfunction of the endothelium compromises the barrier and pump functions of this layer that maintain corneal deturgesence. A large number of corneal endothelial dystrophies feature irregularities in Descemet's membrane, suggesting that cells create and respond to the biophysical signals offered by their underlying matrix. This review provides an overview of the bidirectional relationship between Descemet's membrane and the corneal endothelium. Several experimental methods have characterized a richly topographic and compliant biophysical microenvironment presented by the posterior surface of Descemet's membrane, as well as the ultrastructure and composition of the membrane as it builds during a lifetime. We highlight the signaling pathways involved in the mechanotransduction of biophysical cues that influence cell behavior. We present the specific example of Fuchs' corneal endothelial dystrophy as a condition in which a dysregulated Descemet's membrane may influence the progression of disease. Finally, we discuss some disease models and regenerative strategies that may facilitate improved treatments for corneal dystrophies.
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Affiliation(s)
- Maryam Ali
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, 95616, USA.
| | - VijayKrishna Raghunathan
- The Ocular Surface Institute, College of Optometry, University of Houston, Houston, TX, 77204, USA.
| | - Jennifer Y Li
- Department of Ophthalmology & Vision Science, School of Medicine, UC Davis Medical Center, Sacramento, CA, 95817, USA.
| | - Christopher J Murphy
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, 95616, USA; Department of Ophthalmology & Vision Science, School of Medicine, UC Davis Medical Center, Sacramento, CA, 95817, USA.
| | - Sara M Thomasy
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, 95616, USA.
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ZHAO J, MA XY, FAN TJ. Construction of a tissue-engineered human corneal endothelium and its transplantation in rabbit models. Turk J Biol 2016. [DOI: 10.3906/biy-1508-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Characterization of a corneal endothelium engineered on a self-assembled stromal substitute. Exp Eye Res 2015; 145:125-129. [PMID: 26658713 DOI: 10.1016/j.exer.2015.11.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 11/20/2015] [Accepted: 11/25/2015] [Indexed: 12/13/2022]
Abstract
Endothelial dysfunctions are the first indication for allogeneic corneal transplantation. Development of a tissue-engineered posterior cornea could be an alternative to the use of native allogeneic tissues. In this paper, we used the self-assembly approach to form a cellularized stromal substitute that served as a carrier for the engineering of an endothelium. This endothelialized stromal substitute was then characterized using alizarin red staining, histology, scanning and transmission electron microscopy, as well as mass spectrometry and immunodetection of collagens and function-related proteins. We report the engineering of a monolayer of flattened endothelial cells with a cell density of 966 ± 242 cells/mm(2) (mean ± SD). Endothelial interdigitations were present between cells. The stromal fibroblasts deposited a dense and cohesive collagenous matrix. Collagen fibrils had a diameter of 39.1 ± 11.3 nm, and a mean center to center interfibrillar space of 50.9 ± 10.9 nm. The stromal substitute was composed of collagen types I, V, VI and XII, as well as lumican and decorin. Type IV collagen was also present underneath the endothelium. The endothelium expressed both the sodium/potassium (Na(+)/K(-)) ATPase and sodium/bicarbonate (Na(+)/ [Formula: see text] ) cotransporter pumps. These results indicate that the self-assembled stromal substitute is able to support the expression of endothelial cell functionality markers and therefore, is a suitable carrier for the engineering of an endothelium that could be used for the treatment of endothelial dysfunctions.
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Su CC, Chen CW, Ho WT, Hu FR, Lee SH, Wang IJ. Phenotypes of trypsin- and collagenase-prepared bovine corneal endothelial cells in the presence of a selective Rho kinase inhibitor, Y-27632. Mol Vis 2015; 21:633-43. [PMID: 26097378 PMCID: PMC4455892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 06/02/2015] [Indexed: 10/26/2022] Open
Abstract
PURPOSE To optimize isolation of viable bovine corneal endothelial cells (BCECs), we evaluated the effectiveness of various preparation protocols. This entailed comparing the effects of collagenase A and trypsin in the presence and absence of a Rho kinase inhibitor, Y-27632, on proliferation and tight junctional and cytoskeletal integrity during their expansion. METHODS 5-bromo-2'-deoxyuridine (BrdU) incorporation evaluated cell proliferation. Western blot analysis evaluated F-actin, zonule occludin, and ZO-1 associated nucleic acid binding protein (ZONAB) and RhoA expression. Rho A pulldown assay evaluated Rho A activity. RESULTS In the trypsin (TrypLE)-prepared BCECs, BrdU incorporation decreased whereas nuclear ZONAB expression increased and became stable from day 3 to 7. In contrast, in the collagenase-A-prepared BCECs, we observed preserved ZO-1 integrity, invariant nuclear ZONAB expression, and dense cortical F-actin expression, and BrdU incorporation was invariant from days 1 to 7. Y-27632 did not increase BrdU incorporation and nuclear ZONAB expression in the TrypLE-prepared and the collagenase-A-prepared BCECs. Moreover, Y-27632 increased irregular cellular morphology and downregulated the expression of ZO-1 in the collagenase-A-prepared BCECs from days 1 to 7. Y-27632 inhibited RhoA activation irrespective of whether the cells were isolated with trypsin or collagenase A. CONCLUSIONS It is preferable to isolate BCECs with collagenase A and expand them without Y-27632. With this protocol, proliferative activity and tight junctional and cytoskeletal integrity are better preserved than if trypsin is used in the presence or absence of Y-27632.
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Affiliation(s)
- Chien-Chia Su
- Department of Ophthalmology, National Taiwan University Hospital Hsin-Chu Branch, Hsin-Chu, Taiwan,Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan,Department of Ophthalmology, National Taiwan University Hospital College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chun-Wen Chen
- Department of Ophthalmology, National Taiwan University Hospital College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Wei-Ting Ho
- Department of Ophthalmology, Far Eastern Memorial Hospital, New Taipei City, Taiwan
| | - Fung-Rong Hu
- Department of Ophthalmology, National Taiwan University Hospital College of Medicine, National Taiwan University, Taipei, Taiwan,National Taiwan University College of Medicine, Taipei, Taiwan
| | - Shwu-Huey Lee
- Department of Ophthalmology, Cathay General Hospital, Taipei, Taiwan
| | - I-Jong Wang
- Department of Ophthalmology, National Taiwan University Hospital College of Medicine, National Taiwan University, Taipei, Taiwan,National Taiwan University College of Medicine, Taipei, Taiwan,Department of Ophthalmology, Far Eastern Memorial Hospital, New Taipei City, Taiwan,Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan
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Bolaños-Jiménez R, Navas A, López-Lizárraga EP, de Ribot FM, Peña A, Graue-Hernández EO, Garfias Y. Ocular Surface as Barrier of Innate Immunity. Open Ophthalmol J 2015; 9:49-55. [PMID: 26161163 PMCID: PMC4484240 DOI: 10.2174/1874364101509010049] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 04/06/2015] [Accepted: 04/13/2015] [Indexed: 01/08/2023] Open
Abstract
Sight is one of the most important senses that human beings possess. The ocular system is a complex structure equipped with mechanisms that prevent or limit damage caused by physical, chemical, infectious and environmental factors. These mechanisms include a series of anatomical, cellular and humoral factors that have been a matter of study. The cornea is not only the most powerful and important lens of the optical system, but also, it has been involved in many other physiological and pathological processes apart from its refractive nature; the morphological and histological properties of the cornea have been thoroughly studied for the last fifty years; drawing attention in its molecular characteristics of immune response. This paper will review the anatomical and physiological aspects of the cornea, conjunctiva and lacrimal apparatus, as well as the innate immunity at the ocular surface.
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Affiliation(s)
- Rodrigo Bolaños-Jiménez
- Research Unit, Institute of Ophthalmology, Conde de Valenciana Foundation, Chimalpopoca 14, Obrera, CP 06800, Mexico City, México ; Ophthalmology Department, Regional Hospital, Adolfo López Mateos, ISSSTE, México City, México
| | - Alejandro Navas
- Research Unit, Institute of Ophthalmology, Conde de Valenciana Foundation, Chimalpopoca 14, Obrera, CP 06800, Mexico City, México ; Department of Cataract and refractive surgery, Institute of Ophthalmology, Conde de Valenciana Foundation, Mexico City, México
| | - Erika Paulina López-Lizárraga
- Department of Cataract and refractive surgery, Institute of Ophthalmology, Conde de Valenciana Foundation, Mexico City, México
| | - Francesc March de Ribot
- Department of Retina, Institute of Ophthalmology, Conde de Valenciana Foundation, Mexico City, México
| | - Alexandra Peña
- Ophthalmology Department, Regional Hospital, Adolfo López Mateos, ISSSTE, México City, México
| | - Enrique O Graue-Hernández
- Research Unit, Institute of Ophthalmology, Conde de Valenciana Foundation, Chimalpopoca 14, Obrera, CP 06800, Mexico City, México ; Department of Cataract and refractive surgery, Institute of Ophthalmology, Conde de Valenciana Foundation, Mexico City, México
| | - Yonathan Garfias
- Research Unit, Institute of Ophthalmology, Conde de Valenciana Foundation, Chimalpopoca 14, Obrera, CP 06800, Mexico City, México ; Department of Biochemistry, Faculty of Medicine, Universidad Nacional Autónoma de México, 04510. Mexico City, Mexico
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Bartakova A, Kunzevitzky NJ, Goldberg JL. Regenerative Cell Therapy for Corneal Endothelium. CURRENT OPHTHALMOLOGY REPORTS 2014; 2:81-90. [PMID: 25328857 PMCID: PMC4196268 DOI: 10.1007/s40135-014-0043-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Endothelial cell dysfunction as in Fuchs dystrophy or pseudophakic bullous keratopathy, and the limited regenerative capacity of human corneal endothelial cells (HCECs), drive the need for corneal transplant. In response to limited donor corneal availability, significant effort has been directed towards cell therapy as an alternative to surgery. Stimulation of endogenous progenitors, or transplant of stem cell-derived HCECs or in vitro-expanded, donor-derived HCECs could replace traditional surgery with regenerative therapy. Ex vivo expansion of HCECs is technically challenging, and the basis for molecular identification of functional HCECs is not established. Delivery of cells to the inner layer of the human cornea is another challenge: different techniques, from simple injection to artificial corneal scaffolds, are being investigated. Despite remaining questions, corneal endothelial cell therapies, translated to the clinic, represent the future for the treatment of corneal endotheliopathies.
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Affiliation(s)
- Alena Bartakova
- Shiley Eye Center, University of California San Diego, La Jolla, CA 92093
| | - Noelia J. Kunzevitzky
- Shiley Eye Center, University of California San Diego, La Jolla, CA 92093
- Emmetrope Ophthalmics, Key Biscayne, FL 33149
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Sant'ana VP, Carrijo-Carvalho LC, Foronda AS, Chudzinski-Tavassi AM, de Freitas D, de Carvalho FRS. Cytotoxic activity and degradation patterns of structural proteins by corneal isolates of Acanthamoeba spp. Graefes Arch Clin Exp Ophthalmol 2014; 253:65-75. [PMID: 25161076 DOI: 10.1007/s00417-014-2783-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 06/22/2014] [Accepted: 08/13/2014] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Proteolytic enzymes secreted by trophozoites (amoebic secretome) are suggested as the main virulence factor involved in the severity of Acanthamoeba keratitis. The degradation profile of the main glycoprotein components of anterior and posterior portions of the cornea and the cytopathic effect of secretomes on endothelial cells by contact-independent mechanism were evaluated. METHODS Trophozoites were isolated primarily from corneal tissue samples (n = 11) and extracellular proteins were collected from axenic cell culture supernatants. The molecular weights of proteolytic enzymes were estimated by zymography. Enzymatic cleavage of laminin and fibronectin substrates by amoebic secretome was investigated and cluster analysis was applied to the proteolysis profiles. Primary cultures of endothelial cells were used in both qualitative and quantitative assays of cytophatogenicity. RESULTS Differential patterns of proteolysis were observed among the Acanthamoeba secretomes that were analysed. The uniformity of laminin degradation contrasted with the diversity of the proteolysis profiles observed in the fibronectin substrate. Acanthamoeba secretome extracted from four clinical isolates was shown to be toxic when in contact with the endothelial cell monolayer (p < 0.01). Induction of apoptosis and membrane permeability, at different percentual values, were suggested as the main mechanisms that could induce endothelial cell death when in contact with amoebic secretome. CONCLUSIONS Our results provide evidence that virulence factors secreted by Acanthamoeba trophozoites can be related to an increased pathogenicity pattern by an independent contact-trophozoite mechanism, through induction of endothelial cell death by apoptosis at a higher percentage than providing the lack of cell viability by the membrane-associated pore-forming toxin activity.
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Affiliation(s)
- Viviane Peracini Sant'ana
- Department of Ophthalmology and Visual Sciences, Paulista School of Medicine, Federal University of Sao Paulo, São Paulo, Brazil
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Rajashekhar G, Shivanna M, Kompella UB, Wang Y, Srinivas SP. Role of MMP-9 in the breakdown of barrier integrity of the corneal endothelium in response to TNF-α. Exp Eye Res 2014; 122:77-85. [DOI: 10.1016/j.exer.2014.03.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 03/12/2014] [Accepted: 03/14/2014] [Indexed: 01/11/2023]
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Uchida K, Unuma K, Funakoshi T, Aki T, Uemura K. Activation of Master Autophagy Regulator TFEB During Systemic LPS Administration in the Cornea. J Toxicol Pathol 2014; 27:153-8. [PMID: 25352718 PMCID: PMC4110941 DOI: 10.1293/tox.2014-0004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Accepted: 03/18/2014] [Indexed: 11/22/2022] Open
Abstract
The involvement of autophagy in the cornea during the systemic inflammatory response elicited by intravenous administration of lipopolysaccharide (LPS) was investigated. Eight-week-old male Sprague-Dawley rats were injected i.v. with 15 mg/kg body weight LPS. RC4 rabbit corneal keratocytes were also used and treated with 100 ng/mL of tumor necrosis factor α (TNFα) and/or cycloheximide (CHX). The nuclear translocation of transcription factor EB (TFEB), the master transcriptional regulator for autophagy, was observed after LPS administration in the corneal epithelium. Induction of autophagy-related proteins was observed in the cornea after LPS administration, as well as in RC4 cells after treatment with TNFα. Administration of trehalose, an inducer of TFEB, mitigated RC4 cell death caused by TNFα/CHX. These results demonstrate the importance of TFEB activation in cellular defense against the systemic inflammatory response in the cornea.
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Affiliation(s)
- Kyoko Uchida
- Section of Forensic Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University,Tokyo 113-8519, Japan
| | - Kana Unuma
- Section of Forensic Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University,Tokyo 113-8519, Japan
| | - Takeshi Funakoshi
- Section of Forensic Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University,Tokyo 113-8519, Japan
| | - Toshihiko Aki
- Section of Forensic Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University,Tokyo 113-8519, Japan
| | - Koichi Uemura
- Section of Forensic Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University,Tokyo 113-8519, Japan
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Characteristics of the low density corneal endothelial monolayer. Exp Eye Res 2013; 115:239-45. [PMID: 23830909 DOI: 10.1016/j.exer.2013.06.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Revised: 06/13/2013] [Accepted: 06/24/2013] [Indexed: 11/21/2022]
Abstract
Corneal endothelial cells form a leaky barrier on the posterior surface of the cornea, allowing influx of nutrient-carrying aqueous humor through the paracellular space and efflux of excess fluid. Corneal edema arises when the density of these non-proliferative endothelial cells declines from endothelial disease or intraocular surgery. The cellular changes occurring at low densities are ill-defined. We therefore investigated the paracellular pathway of corneal endothelial cell monolayers of varying density to determine alterations occurring in paracellular permeability and monolayer morphology. Primary cultures of bovine corneal endothelial cells (BCECs) were passaged onto permeable supports under varying culture conditions to obtain confluent monolayers of <1000, 1000-1999 and >2000 cells/mm(2). Culture growth was monitored by transendothelial electrical resistance measurements. Diffusional permeability to sodium fluorescein, FITC-dextran MW 4000 or FITC-dextran MW 20,000 was measured. Confluent cultures were also analyzed by immunofluorescence localization of the tight junction protein ZO-1 and by transmission electron microscopy. For comparison, we evaluated ZO-1 for low and high density human corneal endothelium. Our results showed that all BCEC cultures grew to the same final transendothelial electrical resistance regardless of final density. In the diffusional permeability assay, permeability increased significantly only for the smallest tracer molecule (sodium fluorescein) in the lowest density monolayers (<1000 cells/mm(2)). ZO-1 immunofluorescence distinctly localized to intercellular junctions in high density BCEC cultures but had more diffuse localization at lower densities. Transmission electron microscopy imaging revealed cells with thinner cross-sectional profiles and longer overlapping intercellular processes at low density relative to high density cultures. Low density human corneal endothelium lacked the diffuse ZO-1 distribution seen in BCECs. Our data supports the hypothesis that barrier integrity is the primary function disrupted in low density corneal endothelial monolayers and contradicts the idea of a linear decline in barrier function with decreasing cell density.
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Guo H, Du G, Wang L, Wang D, Hu L, Huang Y. Integrin alpha v beta 6 contributes to maintaining corneal epithelial barrier function. Cell Biol Int 2013; 37:593-9. [PMID: 23412966 DOI: 10.1002/cbin.10076] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2012] [Accepted: 02/06/2013] [Indexed: 01/11/2023]
Affiliation(s)
- Huiling Guo
- Department of Ophthalmology, Chinese PLA General Hospital, Beijing, China; Department of Ophthalmology, Chinese PLA 306 Hospital, Beijing, China
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Patel SP. The bull's eye: are we off-target for corneal endothelial cell physiology? J Ophthalmic Vis Res 2013; 8:83-5. [PMID: 23825720 DOI: pmid/23825720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Sangita P Patel
- Research Service, Veteran Affairs Western New York Healthcare System, Buffalo, NY, USA SUNY Eye Institute, Buffalo, NY, USA
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Mallet JD, Rochette PJ. Wavelength-dependent ultraviolet induction of cyclobutane pyrimidine dimers in the human cornea. Photochem Photobiol Sci 2013; 12:1310-8. [DOI: 10.1039/c3pp25408a] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Ying H, Shen X, Yue BYJT. Establishment of inducible wild type and mutant myocilin-GFP-expressing RGC5 cell lines. PLoS One 2012; 7:e47307. [PMID: 23082156 PMCID: PMC3474840 DOI: 10.1371/journal.pone.0047307] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Accepted: 09/11/2012] [Indexed: 11/22/2022] Open
Abstract
Background Myocilin is a gene linked directly to juvenile- and adult-onset open angle glaucoma. Mutations including Gln368stop (Q368X) and Pro370Leu (P370L) have been identified in patients. The exact role of myocilin and its functional association with glaucoma are still unclear. In the present study, we established tetracycline-inducible (Tet-on) wild type and mutant myocilin-green fluorescence protein (GFP) expressing RGC5 stable cell lines and studied the changes in cell migration and barrier function upon induction. Methodology/Principal Findings After several rounds of selection, clones that displayed low, moderate, or high expression of wild type, Q368X or P370L myocilin-GFP upon doxycycline (Dox) induction were obtained. The levels of wild type and mutant myocilin-GFP in various clones were confirmed by Western blotting. Compared to non-induced controls, the cell migration was retarded, the actin stress fibers were fewer and shorter, and the trypsinization time needed for cells to round up was reduced when wild type or mutant myocilin was expressed. The barrier function was in addition aberrant following induced expression of wild type, Q368X or P370L myocilin. Immunoblotting further showed that tight junction protein occludin was downregulated in induced cells. Conclusions/Significance Tet-on inducible, stable RGC5 cell lines were established. These cell lines, expressing wild type or mutant (Q368X or P370L) myocilin-GFP upon Dox induction, are valuable in facilitating studies such as proteomics, as well as functional and pathogenesis investigations of disease-associated myocilin mutants. The barrier function was found impaired and the migration of cells was hindered with induced expression of wild type and mutant myocilin in RGC5 cell lines. The reduction in barrier function might be related to the declined level of occludin. The retarded cell migration was consistent with demonstrated myocilin phenotypes including the loss of actin stress fibers, lowered RhoA activities and compromised cell-matrix adhesiveness.
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Affiliation(s)
- Hongyu Ying
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, College of Medicine, Chicago, Illinois, United States of America
| | - Xiang Shen
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, College of Medicine, Chicago, Illinois, United States of America
| | - Beatrice Y. J. T. Yue
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, College of Medicine, Chicago, Illinois, United States of America
- * E-mail:
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Penetration of fluorescein across the rabbit cornea from the endothelial surface. Pharm Res 2012; 29:3325-34. [PMID: 22814903 DOI: 10.1007/s11095-012-0824-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Accepted: 07/02/2012] [Indexed: 10/28/2022]
Abstract
PURPOSE To model the kinetics of penetration of fluorescein across the cornea from the endothelial surface. METHODS Rabbit corneas mounted in vitro were exposed to fluorescein at their endothelial surface. Trans-corneal fluorescence were acquired periodically for 6 h using a custom-built confocal microfluorometer. The profiles were then employed to fit a kinetic model for calculation of permeability and diffusion coefficients across the cellular layers and stroma, respectively. RESULTS At the endothelium-stroma and stroma-epithelium interfaces, the fluorescence profile exhibited sudden jumps. In each case, the fluorescence was higher at the stroma, indicating reduced partitioning of the dye into the lipid-rich cellular layers. The stroma did not swell significantly until 180 min of perfusion. The fluorescence profiles reached a pseudo-steady state at ~6 h. A transport model, which included convective and diffusive fluxes into the stroma, showed a good fit to the trans-corneal profiles at different time points. The estimated permeability coefficients for the cellular layers were close to the values reported previously, but the diffusion coefficient of fluorescein in the stroma was found to be smaller than the values obtained previously using Ussing chambers. CONCLUSIONS The penetration of fluorescein could be modeled accurately by a combination of diffusion and convection.
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