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Jin L, Zhang L, Yan C, Liu M, Dean DC, Liu Y. Corneal injury repair and the potential involvement of ZEB1. EYE AND VISION (LONDON, ENGLAND) 2024; 11:20. [PMID: 38822380 PMCID: PMC11143703 DOI: 10.1186/s40662-024-00387-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Accepted: 05/07/2024] [Indexed: 06/03/2024]
Abstract
The cornea, consisting of three cellular and two non-cellular layers, is the outermost part of the eyeball and frequently injured by external physical, chemical, and microbial insults. The epithelial-to-mesenchymal transition (EMT) plays a crucial role in the repair of corneal injuries. Zinc finger E-box binding homeobox 1 (ZEB1), an important transcription factor involved in EMT, is expressed in the corneal tissues. It regulates cell activities like migration, transformation, and proliferation, and thereby affects tissue inflammation, fibrosis, tumor metastasis, and necrosis by mediating various major signaling pathways, including transforming growth factor (TGF)-β. Dysfunction of ZEB1 would impair corneal tissue repair leading to epithelial healing delay, interstitial fibrosis, neovascularization, and squamous cell metaplasia. Understanding the mechanism underlying ZEB1 regulation of corneal injury repair will help us to formulate a therapeutic approach to enhance corneal injury repair.
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Affiliation(s)
- Lin Jin
- Department of Ophthalmology, The Third People's Hospital of Dalian, Dalian Medical University, Dalian, 116033, China
| | - Lijun Zhang
- Department of Ophthalmology, The Third People's Hospital of Dalian, Dalian Medical University, Dalian, 116033, China
| | - Chunxiao Yan
- Department of Ophthalmology, The Third People's Hospital of Dalian, Dalian Medical University, Dalian, 116033, China
| | - Mengxin Liu
- Department of Ophthalmology, The Third People's Hospital of Dalian, Dalian Medical University, Dalian, 116033, China
| | - Douglas C Dean
- James Brown Cancer Center, University of Louisville School of Medicine, Louisville, KY, 40202, USA.
- Department of Medicine, University of Louisville School of Medicine, Louisville, KY, 40202, USA.
| | - Yongqing Liu
- James Brown Cancer Center, University of Louisville School of Medicine, Louisville, KY, 40202, USA.
- Department of Medicine, University of Louisville School of Medicine, Louisville, KY, 40202, USA.
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Hamed MA, Farag A, Zahran IS, Hafez A, Rizk MA, Abass M. Pycnogenol a promising remedy for diabetic keratopathy in experimentally induced corneal alkali burns in diabetic rats. BMC Vet Res 2022; 18:209. [PMID: 35637465 PMCID: PMC9150323 DOI: 10.1186/s12917-022-03307-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 05/17/2022] [Indexed: 11/10/2022] Open
Abstract
AIM This study aimed to investigate the efficiency of topically applied pycnogenol (PYC) in healing the standardized alkaline corneal ulcer in diabetic and normal rats. MATERIALS AND METHODS The corneal alkali-burn injury (CA-I) model was unilaterally developed in Wistar rats by filter paper saturated with 0.01 M of NaOH and touching the eyes for 45 s. Rats were divided into four groups: Normal control (NC), normal PYC (NPYC), diabetic control (DC), and diabetic PYC (DPYC). Both NPYC and DPYC groups were daily treated with PY eye drops three times, whereas NC and DC ones were treated with ordinary saline for six successive days. RESULTS The wound healing of corneal epithelial was improved in the NPYC group compared to the NC group. Meanwhile, it was significantly improved (P < 0.05) in the DPYC group than in the DC group. Histological examination revealed that corneal re-epithelialization was more accomplished in the DPYC group than in the DC group. In addition, the inflammatory cells were augmented in the DC group more than those in the DPYC one. CONCLUSION The findings obtained revealed the efficiency of PYC for enhancing the corneal re-epithelialization and reducing the inflammatory reaction post alkali burn in rats, and thus it could be beneficially valuable as a treatment for the diabetic keratopathy.
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Affiliation(s)
- Mohamed A. Hamed
- Department of Surgery, Anesthesiology, and Radiology, Faculty of Veterinary Medicine, Aswan University, Aswan, Egypt
| | - Amany Farag
- Department of Cytology and Histology, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516 Egypt
| | - Ibrahim S. Zahran
- Department of Physiology, Faculty of Veterinary Medicine, Aswan University, Aswan, Egypt
| | - Ahmed Hafez
- Department of Pharmacology, Faculty of Veterinary Medicine, Aswan University, Aswan, Egypt
| | - Mohamed Abdo Rizk
- Department of Internal Medicine, Infectious and Fish Diseases, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516 Egypt
| | - Marwa Abass
- Department of Surgery, Anesthesiology, and Radiology, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516 Egypt
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Kamil S, Mohan RR. Corneal stromal wound healing: Major regulators and therapeutic targets. Ocul Surf 2020; 19:290-306. [PMID: 33127599 DOI: 10.1016/j.jtos.2020.10.006] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 10/16/2020] [Accepted: 10/25/2020] [Indexed: 12/12/2022]
Abstract
Corneal stromal wound healing is a complex event that occurs to restore the transparency of an injured cornea. It involves immediate apoptosis of keratocytes followed by their activation, proliferation, migration, and trans-differentiation to myofibroblasts. Myofibroblasts contract to close the wound and secrete extracellular matrix and proteinases to remodel it. Released proteinases may degenerate the basement membrane allowing an influx of cytokines from overlying epithelium. Immune cells infiltrate the wound to clear cellular debris and prevent infections. Gradually basement membrane regenerates, myofibroblasts and immune cells disappear, abnormal matrix is resorbed, and transparency of the cornea is restored. Often this cascade deregulates and corneal opacity results. Factors that prevent corneal opacity after an injury have always intrigued the researchers. They hold clinical relevance as they can guide the outcomes of corneal surgeries. Studies in the past have shed light on the role of various factors in stromal healing. TGFβ (transforming growth factor-beta) signaling is the central player guiding stromal responses. Other major regulators include myofibroblasts, basement membrane, collagen fibrils, small leucine-rich proteoglycans, biophysical cues, proteins derived from extracellular matrix, and membrane channels. The knowledge about their roles helped to develop novel therapies to prevent corneal opacity. This article reviews the role of major regulators that determine the outcome of stromal healing. It also discusses emerging therapies that modulate the role of these regulators to prevent stromal opacity.
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Affiliation(s)
- Sabeeh Kamil
- Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, USA; One-Health Vision Research Program, Department of Veterinary Medicine & Surgery and Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Rajiv R Mohan
- Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, USA; One-Health Vision Research Program, Department of Veterinary Medicine & Surgery and Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA; Mason Eye Institute, School of Medicine, University of Missouri, Columbia, MO, USA.
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Giannaccare G, Pellegrini M, Bovone C, Spena R, Senni C, Scorcia V, Busin M. Anti-VEGF Treatment in Corneal Diseases. Curr Drug Targets 2020; 21:1159-1180. [PMID: 32189591 DOI: 10.2174/1389450121666200319111710] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 12/31/2019] [Accepted: 01/20/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Corneal neovascularization (CN) is a clue feature of different ocular pathological conditions and can lead to corneal edema and opacification with subsequent vision loss. Vascular endothelial growth factor (VEGF), which plays a key role in new vessels formation, proliferation and migration, was found to be up-regulated in these conditions. Nowadays, it is possible to downregulate the angiogenic process by using anti-VEGF agents administered by different routes. OBJECTIVE To evaluate the efficacy, safety and possible future directions of anti-VEGF agents used for the treatment of CNV owing to different aetiologies. METHODS A computerized search of articles dealing with the topic of anti-VEGF therapy in CN was conducted in PubMed, Scopus and Medline electronic databases. The following key phrases were used: anti-VEGF agents, corneal neovascularization, bevacizumab, ranibizumab, vascular endothelial growth factor, angiogenesis. RESULTS The use of anti-VEGF therapy in the treatment of CN reduced pathological vessel density without causing significant side effects. Various administration routes such as topical, subconjunctival and intrastromal ones are available, and the choice depends on patient and disease characteristics. Much more effectiveness is achieved in case of early administration before mature and wellestablished vessels take place. A combined approach between various drugs including anti-VEGF agents should be adopted in those cases at higher risk of neovascularization recurrence such as chronic long-standing diseases where ischemic and inflammatory stimuli are not definitively reversed. CONCLUSION The efficacy and safety of anti-VEGF agents support their adoption into the daily clinical practice for the management of CN.
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Affiliation(s)
- Giuseppe Giannaccare
- Department of Ophthalmology, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | | | - Cristina Bovone
- Department of Ophthalmology, Ospedale Privato "Villa Igea", Forli, Italy
| | - Rossella Spena
- Department of Ophthalmology, Ospedale Privato "Villa Igea", Forli, Italy
| | - Carlotta Senni
- Ophthalmology Unit, University of Bologna, Bologna, Italy
| | - Vincenzo Scorcia
- Department of Ophthalmology, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Massimo Busin
- Department of Ophthalmology, Ospedale Privato "Villa Igea", Forli, Italy
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Zhou C, Singh A, Qian G, Wolkow N, Dohlman CH, Vavvas DG, Chodosh J, Paschalis EI. Microporous Drug Delivery System for Sustained Anti-VEGF Delivery to the Eye. Transl Vis Sci Technol 2020; 9:5. [PMID: 32855852 PMCID: PMC7422759 DOI: 10.1167/tvst.9.8.5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 05/04/2020] [Indexed: 11/24/2022] Open
Abstract
Purpose To describe a novel microporous drug delivery system (DDS) for sustained anti- vascular endothelial growth factor (VEGF) delivery to the eye and to evaluate its efficacy in a corneal injury model. Methods A macro-porous DDS (1.5 × 1.5 × 4 mm) loaded with 2 mg of bevacizumab was implanted subconjunctivally in three Dutch-belted pigmented rabbits after corneal alkali injury (2N NaOH). Three rabbits received sham DDS. Animals were followed for three months and assessed in vivo and ex vivo for corneal neovascularization (NV), epithelial defect, stromal scarring, endothelial cell loss, and expression of angiogenic and inflammatory markers in the cornea and retina. Results Anti-VEGF DDS treatment led to complete inhibition of superior cornea NV and complete corneal re-epithelialization by day 58 whereas sham DDS resulted in severe cornea NV and persistent epithelial defect (9%∼12% of total cornea area) through the end of the study. Histologically, anti-VEGF DDS significantly reduced CD45+ and F4/80 CD11b+ cell accumulation (79%, P < 0.05) in the cornea, ameliorated tumor necrosis factor–α expression (90%, P < 0.05), reduced corneal stromal scarring and prevented corneal endothelial cell loss, as compared to sham DDS. Moreover, anti-VEGF DDS achieved retinal penetration and reduction in retinal VEGF levels at 3 months. Conclusions Use of subconjunctival anti-VEGF DDS suppresses cornea NV, inflammation, stromal scarring, prevents endothelial cell loss, and abrogates retinal VEGF upregulation in a rabbit corneal alkali burn model. Moreover, it delivers anti-VEGF antibodies to the retina for three months. This delivery platform could enable antibody therapy of other corneal and retinal vascular pathologies. Translational Relevance We describe a method for sustained anti-VEGF delivery to the eye for the treatment of ocular injuries.
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Affiliation(s)
- Chengxin Zhou
- Boston Keratoprosthesis Laboratory, Department of Ophthalmology, Massachusetts Eye and Ear and Schepens Eye Research Institute, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
| | - Arushi Singh
- Boston Keratoprosthesis Laboratory, Department of Ophthalmology, Massachusetts Eye and Ear and Schepens Eye Research Institute, Boston, MA, USA
| | - Grace Qian
- Boston Keratoprosthesis Laboratory, Department of Ophthalmology, Massachusetts Eye and Ear and Schepens Eye Research Institute, Boston, MA, USA
| | - Natalie Wolkow
- Harvard Medical School, Boston, MA, USA.,David G. Cogan Laboratory of Eye Pathology and Ophthalmic Plastic Surgery Service, Massachusetts Eye and Ear Infirmary, Boston, MA, USA
| | - Claes H Dohlman
- Boston Keratoprosthesis Laboratory, Department of Ophthalmology, Massachusetts Eye and Ear and Schepens Eye Research Institute, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
| | - Demetrios G Vavvas
- Angiogenesis Laboratory, Retina Service, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - James Chodosh
- Boston Keratoprosthesis Laboratory, Department of Ophthalmology, Massachusetts Eye and Ear and Schepens Eye Research Institute, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA.,Disruptive Technology Laboratory (D.T.L.), Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Eleftherios I Paschalis
- Boston Keratoprosthesis Laboratory, Department of Ophthalmology, Massachusetts Eye and Ear and Schepens Eye Research Institute, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA.,Disruptive Technology Laboratory (D.T.L.), Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
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Rocher M, Robert PY, Desmoulière A. The myofibroblast, biological activities and roles in eye repair and fibrosis. A focus on healing mechanisms in avascular cornea. Eye (Lond) 2019; 34:232-240. [PMID: 31767967 DOI: 10.1038/s41433-019-0684-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 10/17/2019] [Accepted: 10/24/2019] [Indexed: 02/08/2023] Open
Abstract
Tissue healing is one of the mysteries of modern medicine. Healing involves complex processes and many cellular types, amongst which the myofibroblast plays a major role. In the eye, when needed, myofibroblasts can be found from the cornea to the retina, derived from a wide variety of different cells, and aimed at effectively repairing tissue damage. Myofibroblast differentiation requires transforming growth factor (TGF)-β1, the presence of specific extracellular matrix components such as the ED-A domain of fibronectin, and mechanical tension. Control of this process may, in some cases, be abnormal leading to development of fibrotic tissue, which alters and compromises the integrity of the original tissue. The eye is no exception to this rule with normal visual function, a highly demanding process, only possible in a fully integrated organ. The cornea, a transparent protective tissue and first dioptre of the eye, has the particularity of being entirely avascular and very richly innervated under normal physiological conditions. However, these anatomical features do not prevent it from developing myofibroblasts in the event of a deep corneal lesion. Activated by growth factors such as TGF-β1 and platelet-derived growth factor from the aqueous humour, tears or corneal epithelial cells, myofibroblasts can cause corneal scarring, sometimes with devastating consequences. Understanding the factors involved in healing and its signalling pathways, will potentially enable us to control corneal healing in the future, and thus avoid fibrotic ocular surface disease and the blindness that this may induce. Currently, this issue is the subject of very active research and development with the aim of discovering new antifibrotic therapies.
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Affiliation(s)
- Maxime Rocher
- Department of Ophthalmology, Limoges University Hospital, F-87000, Limoges, France
| | - Pierre-Yves Robert
- Department of Ophthalmology, Limoges University Hospital, F-87000, Limoges, France
| | - Alexis Desmoulière
- Department of Physiology and EA 6309, Faculties of Medicine and Pharmacy, University of Limoges, F-87000, Limoges, France.
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Shu DY, Lovicu FJ. Myofibroblast transdifferentiation: The dark force in ocular wound healing and fibrosis. Prog Retin Eye Res 2017; 60:44-65. [PMID: 28807717 PMCID: PMC5600870 DOI: 10.1016/j.preteyeres.2017.08.001] [Citation(s) in RCA: 236] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 08/08/2017] [Accepted: 08/09/2017] [Indexed: 02/06/2023]
Abstract
Wound healing is one of the most complex biological processes to occur in life. Repair of tissue following injury involves dynamic interactions between multiple cell types, growth factors, inflammatory mediators and components of the extracellular matrix (ECM). Aberrant and uncontrolled wound healing leads to a non-functional mass of fibrotic tissue. In the eye, fibrotic disease disrupts the normally transparent ocular tissues resulting in irreversible loss of vision. A common feature in fibrotic eye disease is the transdifferentiation of cells into myofibroblasts that can occur through a process known as epithelial-mesenchymal transition (EMT). Myofibroblasts rapidly produce excessive amounts of ECM and exert tractional forces across the ECM, resulting in the distortion of tissue architecture. Transforming growth factor-beta (TGFβ) plays a major role in myofibroblast transdifferentiation and has been implicated in numerous fibrotic eye diseases including corneal opacification, pterygium, anterior subcapsular cataract, posterior capsular opacification, proliferative vitreoretinopathy, fibrovascular membrane formation associated with proliferative diabetic retinopathy, submacular fibrosis, glaucoma and orbital fibrosis. This review serves to introduce the pathological functions of the myofibroblast in fibrotic eye disease. We also highlight recent developments in elucidating the multiple signaling pathways involved in fibrogenesis that may be exploited in the development of novel anti-fibrotic therapies to reduce ocular morbidity due to scarring.
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Affiliation(s)
- Daisy Y Shu
- Discipline of Anatomy and Histology, Bosch Institute, University of Sydney, NSW, Australia; Save Sight Institute, University of Sydney, NSW, Australia
| | - Frank J Lovicu
- Discipline of Anatomy and Histology, Bosch Institute, University of Sydney, NSW, Australia; Save Sight Institute, University of Sydney, NSW, Australia.
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Choi H, Phillips C, Oh JY, Stock EM, Kim DK, Won JK, Fulcher S. Comprehensive Modeling of Corneal Alkali Injury in the Rat Eye. Curr Eye Res 2017. [DOI: 10.1080/02713683.2017.1317817] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Hosoon Choi
- Department of Basic Research, Central Texas Veterans Research Foundation, Temple, TX, USA
| | - Casie Phillips
- Department of Basic Research, Central Texas Veterans Research Foundation, Temple, TX, USA
| | - Joo Youn Oh
- Department of Ophthalmology, Seoul National University Hospital, Daehak-ro, Jongno-gu, Seoul, Republic of Korea
| | - Eileen M. Stock
- Cooperative Studies Program Coordinating Center, VA Maryland Health Care System, Perry Point, MD, USA
| | - Dong-Ki Kim
- Institute for Regenerative Medicine, Texas A&M Health Science Center, College Station, TX, USA
| | - Jae-Kyung Won
- Department of Pathology, Seoul National University Hospital, Daehak-ro, Jongno-gu, Seoul, Republic of Korea
| | - Samuel Fulcher
- Department of Surgery, Ophthalmology Section, Central Texas Veterans Health Care System, Temple, TX, USA
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Cejkova J, Cejka C, Trosan P, Zajicova A, Sykova E, Holan V. Treatment of alkali-injured cornea by cyclosporine A-loaded electrospun nanofibers – An alternative mode of therapy. Exp Eye Res 2016; 147:128-137. [DOI: 10.1016/j.exer.2016.04.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Revised: 02/14/2016] [Accepted: 04/19/2016] [Indexed: 11/29/2022]
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Stepp MA, Zieske JD, Trinkaus-Randall V, Kyne BM, Pal-Ghosh S, Tadvalkar G, Pajoohesh-Ganji A. Wounding the cornea to learn how it heals. Exp Eye Res 2014; 121:178-93. [PMID: 24607489 DOI: 10.1016/j.exer.2014.02.007] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 02/07/2014] [Accepted: 02/10/2014] [Indexed: 12/12/2022]
Abstract
Corneal wound healing studies have a long history and rich literature that describes the data obtained over the past 70 years using many different species of animals and methods of injury. These studies have lead to reduced suffering and provided clues to treatments that are now helping patients live more productive lives. In spite of the progress made, further research is required since blindness and reduced quality of life due to corneal scarring still happens. The purpose of this review is to summarize what is known about different types of wound and animal models used to study corneal wound healing. The subject of corneal wound healing is broad and includes chemical and mechanical wound models. This review focuses on mechanical injury models involving debridement and keratectomy wounds to reflect the authors' expertise.
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Affiliation(s)
- Mary Ann Stepp
- Department of Anatomy and Regenerative Biology, The George Washington University Medical Center, Washington, DC 20037, USA; Department of Ophthalmology, The George Washington University Medical Center, Washington, DC 20037, USA.
| | - James D Zieske
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114-2500, USA
| | - Vickery Trinkaus-Randall
- Department of Ophthalmology, Boston University School of Medicine, Boston, MA 02118, USA; Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118, USA
| | - Briana M Kyne
- Department of Anatomy and Regenerative Biology, The George Washington University Medical Center, Washington, DC 20037, USA
| | - Sonali Pal-Ghosh
- Department of Anatomy and Regenerative Biology, The George Washington University Medical Center, Washington, DC 20037, USA
| | - Gauri Tadvalkar
- Department of Anatomy and Regenerative Biology, The George Washington University Medical Center, Washington, DC 20037, USA
| | - Ahdeah Pajoohesh-Ganji
- Department of Anatomy and Regenerative Biology, The George Washington University Medical Center, Washington, DC 20037, USA
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