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Acosta AC, Joud H, Sun M, Avila MY, Margo CE, Espana EM. Keratocyte-Derived Myofibroblasts: Functional Differences With Their Fibroblast Precursors. Invest Ophthalmol Vis Sci 2023; 64:9. [PMID: 37796488 PMCID: PMC10561788 DOI: 10.1167/iovs.64.13.9] [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: 01/09/2023] [Accepted: 09/05/2023] [Indexed: 10/06/2023] Open
Abstract
Purpose In this study, we aim to elucidate functional differences between fibroblasts and myofibroblasts derived from a keratocyte lineage to better understand corneal scarring. Methods Corneal fibroblasts, derived from a novel triple transgenic conditional KeraRT/tetO-Cre/mTmG mouse strain that allows isolation and tracking of keratocyte lineage, were expanded, and transformed by exposure to transforming growth factor (TGF)-β1 to myofibroblasts. The composition and organization of a fibroblast-built matrix, deposited by fibroblasts in vitro, was analyzed and compared to the composition of an in vitro matrix built by myofibroblasts. Second harmonic generation microscopy (SHG) was used to study collagen organization in deposited matrix. Different extracellular matrix proteins, expressed by fibroblasts or myofibroblasts, were analyzed and quantified. Functional assays compared latent (TGF-β) activation, in vitro wound healing, chemotaxis, and proliferation between fibroblasts and myofibroblasts. Results We found significant differences in cell morphology between fibroblasts and myofibroblasts. Fibroblasts expressed and deposited significantly higher quantities of fibril forming corneal collagens I and V. In contrast, myofibroblasts expressed and deposited higher quantities of fibronectin and other non-collagenous matrix components. A significant difference in the activation of latent TGF-β activation exists between fibroblasts and myofibroblasts when measured with a functional luciferase assay. Fibroblasts and myofibroblasts differ in their morphology, extracellular matrix synthesis, and deposition, activation of latent TGF-β, and chemotaxis. Conclusions The differences in the expression and deposition of extracellular matrix components by fibroblasts and myofibroblasts are likely related to critical roles they play during different stages of corneal wound healing.
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Affiliation(s)
- Ana C. Acosta
- Cornea and External Disease, Department of Ophthalmology, University of South Florida, Tampa, Florida, United States
| | - Hadi Joud
- Cornea and External Disease, Department of Ophthalmology, University of South Florida, Tampa, Florida, United States
| | - Mei Sun
- Cornea and External Disease, Department of Ophthalmology, University of South Florida, Tampa, Florida, United States
| | - Marcel Y. Avila
- Departamento de Oftalmologia, Universidad Nacional de Colombia, Bogota, Colombia
| | - Curtis E. Margo
- Cornea and External Disease, Department of Ophthalmology, University of South Florida, Tampa, Florida, United States
- Department of Pathology and Cellular Biology, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
| | - Edgar M. Espana
- Cornea and External Disease, Department of Ophthalmology, University of South Florida, Tampa, Florida, United States
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
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2
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Acosta AC, Sun M, Zafrullah N, Avila MY, Margo CE, Espana EM. Stromal matrix directs corneal fibroblasts to re-express keratocan after injury and transplantation. Dis Model Mech 2023; 16:dmm050090. [PMID: 37702214 PMCID: PMC10508697 DOI: 10.1242/dmm.050090] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Accepted: 08/09/2023] [Indexed: 09/14/2023] Open
Abstract
Every tissue has an extracellular matrix (ECM) with certain properties unique to it - the tissue 'niche' - that are necessary for normal function. A distinct specific population of quiescent keratocan-expressing keratocytes populate the corneal stroma during homeostasis to maintain corneal function. However, during wound healing, when there is alteration of the niche conditions, keratocytes undergo apoptosis, and activated corneal fibroblasts and myofibroblasts attempt to restore tissue integrity and function. It is unknown what the fate of activated and temporary fibroblasts and myofibroblasts is after the wound healing process has resolved. In this study, we used several strategies to elucidate the cellular dynamics of corneal wound healing and the fate of corneal fibroblasts. We injured the cornea of a novel mouse model that allows cell-lineage tracing, and we transplanted a cell suspension of in vitro-expanded corneal fibroblasts that could be tracked after being relocated into normal stroma. These transplanted fibroblasts regained expression of keratocan in vivo when relocated to a normal stromal niche. These findings suggest that transformed fibroblasts maintain plasticity and can be induced to a keratocyte phenotype once relocated to an ECM with normal signaling ECM.
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Affiliation(s)
- Ana C. Acosta
- Cornea and External Disease, Department of Ophthalmology, USF Health, 13330 USF Laurel Dr 4th floor, Tampa FL 33612, USA
| | - Mei Sun
- Cornea and External Disease, Department of Ophthalmology, USF Health, 13330 USF Laurel Dr 4th floor, Tampa FL 33612, USA
| | - Nabeel Zafrullah
- Cornea and External Disease, Department of Ophthalmology, USF Health, 13330 USF Laurel Dr 4th floor, Tampa FL 33612, USA
| | - Marcel Y. Avila
- Universidad Nacional de Colombia, Department of Ophthalmology, Bogota 111311, Colombia
| | - Curtis E. Margo
- Cornea and External Disease, Department of Ophthalmology, USF Health, 13330 USF Laurel Dr 4th floor, Tampa FL 33612, USA
- Department of Pathology and Cellular Biology, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Edgar M. Espana
- Cornea and External Disease, Department of Ophthalmology, USF Health, 13330 USF Laurel Dr 4th floor, Tampa FL 33612, USA
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, FL 33612, USA
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Donovan C, Sun M, Cogswell D, Margo CE, Avila MY, Espana EM. Genipin increases extracellular matrix synthesis preventing corneal perforation. Ocul Surf 2023; 28:115-123. [PMID: 36871831 PMCID: PMC10440284 DOI: 10.1016/j.jtos.2023.02.003] [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: 01/17/2023] [Revised: 02/04/2023] [Accepted: 02/06/2023] [Indexed: 03/06/2023]
Abstract
PURPOSE Corneal melting and perforation are feared sight-threatening complications of infections, autoimmune disease, and severe burns. Assess the use of genipin in treating stromal melt. METHODS A model for corneal wound healing was created through epithelial debridement and mechanical burring to injure the corneal stromal matrix in adult mice. Murine corneas were then treated with varying concentrations of genipin, a natural occurring crosslinking agent, to investigate the effects that matrix crosslinking using genipin has in wound healing and scar formation. Genipin was used in patients with active corneal melting. RESULTS Corneas treated with higher concentrations of genipin were found to develop denser stromal scarring in a mouse model. In human corneas, genipin promoted stromal synthesis and prevention of continuous melt. Genipin mechanisms of action create a favorable environment for upregulation of matrix synthesis and corneal scarring. CONCLUSION Our data suggest that genipin increases matrix synthesis and inhibits the activation of latent transforming growth factor-β. These findings are translated to patients with severe corneal melting.
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Affiliation(s)
| | - Mei Sun
- Department of Ophthalmology, USA
| | | | - Curtis E Margo
- Department of Ophthalmology, USA; Pathology and Cell Biology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Marcel Y Avila
- Department of Ophthalmology, Universidad Nacional de Colombia, Bogota, Colombia
| | - Edgar M Espana
- Department of Ophthalmology, USA; Molecular Pharmacology and Physiology, USA.
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Gao H, Qian R, Ren Q, Zhang L, Qin W, Zhou C, Wang H, Liu C, Zhang Y. The upregulation of keratocan promotes the progression of human pancreatic cancer. Mol Cell Toxicol 2023. [DOI: 10.1007/s13273-023-00342-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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Tavakkoli F, Damala M, Koduri MA, Gangadharan A, Rai AK, Dash D, Basu S, Singh V. Transcriptomic Profiling of Human Limbus-Derived Stromal/Mesenchymal Stem Cells-Novel Mechanistic Insights into the Pathways Involved in Corneal Wound Healing. Int J Mol Sci 2022; 23:ijms23158226. [PMID: 35897793 PMCID: PMC9368612 DOI: 10.3390/ijms23158226] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 07/16/2022] [Accepted: 07/16/2022] [Indexed: 01/27/2023] Open
Abstract
Limbus-derived stromal/mesenchymal stem cells (LMSCs) are vital for corneal homeostasis and wound healing. However, despite multiple pre-clinical and clinical studies reporting the potency of LMSCs in avoiding inflammation and scarring during corneal wound healing, the molecular basis for the ability of LMSCs remains unknown. This study aimed to uncover the factors and pathways involved in LMSC-mediated corneal wound healing by employing RNA-Sequencing (RNA-Seq) in human LMSCs for the first time. We characterized the cultured LMSCs at the stages of initiation (LMSC−P0) and pure population (LMSC−P3) and subjected them to RNA-Seq to identify the differentially expressed genes (DEGs) in comparison to native limbus and cornea, and scleral tissues. Of the 28,000 genes detected, 7800 DEGs were subjected to pathway-specific enrichment Gene Ontology (GO) analysis. These DEGs were involved in Wnt, TGF-β signaling pathways, and 16 other biological processes, including apoptosis, cell motility, tissue remodeling, and stem cell maintenance, etc. Two hundred fifty-four genes were related to wound healing pathways. COL5A1 (11.81 ± 0.48) and TIMP1 (20.44 ± 0.94) genes were exclusively up-regulated in LMSC−P3. Our findings provide new insights involved in LMSC-mediated corneal wound healing.
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Affiliation(s)
- Fatemeh Tavakkoli
- Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India; (F.T.); (M.D.); (M.A.K.); (S.B.)
- Center for Genetic Disorders, Banaras Hindu University, Varanasi 221005, India;
| | - Mukesh Damala
- Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India; (F.T.); (M.D.); (M.A.K.); (S.B.)
- School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Madhuri Amulya Koduri
- Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India; (F.T.); (M.D.); (M.A.K.); (S.B.)
- Manipal Academy of Higher Education, Manipal 576104, India
| | - Abhilash Gangadharan
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road Campus, New Delhi 110025, India; (A.G.); (D.D.)
| | - Amit K. Rai
- Center for Genetic Disorders, Banaras Hindu University, Varanasi 221005, India;
| | - Debasis Dash
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road Campus, New Delhi 110025, India; (A.G.); (D.D.)
| | - Sayan Basu
- Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India; (F.T.); (M.D.); (M.A.K.); (S.B.)
- Center for Ocular Regeneration (CORE), Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India
| | - Vivek Singh
- Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India; (F.T.); (M.D.); (M.A.K.); (S.B.)
- Center for Ocular Regeneration (CORE), Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India
- Correspondence: ; Tel.: +91-40-6810-2286
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binte M. Yusoff NZ, Riau AK, Yam GHF, binte Halim NSH, Mehta JS. Isolation and Propagation of Human Corneal Stromal Keratocytes for Tissue Engineering and Cell Therapy. Cells 2022; 11:cells11010178. [PMID: 35011740 PMCID: PMC8750693 DOI: 10.3390/cells11010178] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 12/20/2021] [Accepted: 12/29/2021] [Indexed: 12/13/2022] Open
Abstract
The human corneal stroma contains corneal stromal keratocytes (CSKs) that synthesize and deposit collagens and keratan sulfate proteoglycans into the stromal matrix to maintain the corneal structural integrity and transparency. In adult corneas, CSKs are quiescent and arrested in the G0 phase of the cell cycle. Following injury, some CSKs undergo apoptosis, whereas the surviving cells are activated to become stromal fibroblasts (SFs) and myofibroblasts (MyoFBs), as a natural mechanism of wound healing. The SFs and MyoFBs secrete abnormal extracellular matrix proteins, leading to corneal fibrosis and scar formation (corneal opacification). The issue is compounded by the fact that CSK transformation into SFs or MyoFBs is irreversible in vivo, which leads to chronic opacification. In this scenario, corneal transplantation is the only recourse. The application of cell therapy by replenishing CSKs, propagated in vitro, in the injured corneas has been demonstrated to be efficacious in resolving early-onset corneal opacification. However, expanding CSKs is challenging and has been the limiting factor for the application in corneal tissue engineering and cell therapy. The supplementation of serum in the culture medium promotes cell division but inevitably converts the CSKs into SFs. Similar to the in vivo conditions, the transformation is irreversible, even when the SF culture is switched to a serum-free medium. In the current article, we present a detailed protocol on the isolation and propagation of bona fide human CSKs and the morphological and genotypic differences from SFs.
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Affiliation(s)
- Nur Zahirah binte M. Yusoff
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore 169856, Singapore; (N.Z.b.M.Y.); (A.K.R.); (N.S.H.b.H.)
| | - Andri K. Riau
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore 169856, Singapore; (N.Z.b.M.Y.); (A.K.R.); (N.S.H.b.H.)
- Ophthalmology and Visual Sciences Academic Clinical Programme, Duke-NUS Medical School, Singapore 169857, Singapore
| | - Gary H. F. Yam
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213, USA;
| | - Nuur Shahinda Humaira binte Halim
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore 169856, Singapore; (N.Z.b.M.Y.); (A.K.R.); (N.S.H.b.H.)
| | - Jodhbir S. Mehta
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore 169856, Singapore; (N.Z.b.M.Y.); (A.K.R.); (N.S.H.b.H.)
- Ophthalmology and Visual Sciences Academic Clinical Programme, Duke-NUS Medical School, Singapore 169857, Singapore
- Corneal and External Eye Disease Department, Singapore National Eye Centre, Singapore 168751, Singapore
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
- Correspondence: ; Tel.: +65-6322-8378
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Jhanji V, Billig I, Yam GHF. Cell-Free Biological Approach for Corneal Stromal Wound Healing. Front Pharmacol 2021; 12:671405. [PMID: 34122095 PMCID: PMC8193853 DOI: 10.3389/fphar.2021.671405] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 05/17/2021] [Indexed: 12/13/2022] Open
Abstract
Corneal opacification is the fourth most common cause of blindness globally behind cataracts, glaucoma, and age-related macular degeneration. The standard treatment of serious corneal scarring is corneal transplantation. Though it is effective for restoring vision, the treatment outcome is not optimal, due to limitations such as long-term graft survival, lifelong use of immunosuppressants, and a loss of corneal strength. Regulation of corneal stromal wound healing, along with inhibition or downregulation of corneal scarring is a promising approach to prevent corneal opacification. Pharmacological approaches have been suggested, however these are fraught with side effects. Tissue healing is an intricate process that involves cell death, proliferation, differentiation, and remodeling of the extracellular matrix. Current research on stromal wound healing is focused on corneal characteristics such as the immune response, angiogenesis, and cell signaling. Indeed, promising new technologies with the potential to modulate wound healing are under development. In this review, we provide an overview of cell-free strategies and some approaches under development that have the potential to control stromal fibrosis and scarring, especially in the context of early intervention.
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Affiliation(s)
- Vishal Jhanji
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Isabelle Billig
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Gary Hin-Fai Yam
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States
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8
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Sharifi S, Islam MM, Sharifi H, Islam R, Nilsson PH, Dohlman CH, Mollnes TE, Paschalis EI, Chodosh J. Sputter Deposition of Titanium on Poly(Methyl Methacrylate) Enhances Corneal Biocompatibility. Transl Vis Sci Technol 2020; 9:41. [PMID: 33442495 PMCID: PMC7774111 DOI: 10.1167/tvst.9.13.41] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Accepted: 11/15/2020] [Indexed: 02/07/2023] Open
Abstract
Purpose To evaluate titanium (Ti) sputtering of the poly(methyl methacrylate) (PMMA) stem of the Boston Keratoprosthesis (BK) as a method to enhance interfacial adhesion between the PMMA and the recipient corneal tissue. Methods PMMA specimens were plasma treated with Ar/O2 and coated with Ti using a DC magnetron sputtering instrument. The topography and hydrophilicity of the surfaces were characterized using atomic force microscopy and a water contact angle instrument, respectively. Scratch hardness and adhesion of the Ti film were measured using a mechanical tester. Biocompatibility assessments were performed using cultured human corneal fibroblasts and whole blood ex vivo. The optical quality of the Ti sputtered BK was evaluated using a custom-made optical bench. Results By contact angle studies, the Ti coating improved PMMA hydrophilicity to match that of medical-grade Ti (Ti-6Al-4V-ELI). Ti sputtering of contact surfaces resulted in a plate-like morphology with increased surface roughness, without impacting the transparency of the BK optical component. Scratch testing indicated that the mechanical behavior of the Ti coating was similar to that of casted Ti, and the coating was stable in pull-off adhesion testing. Sputtered Ti film was highly biocompatible based on tests of cell viability, adhesion, proliferation, differentiation, collagen deposition, and keratocan expression, the properties of which exceeded those of uncoated PMMA and did not induce increased complement activation. Conclusions Titanium coating of the BK stem generated a mechanically and biologically favorable interface, which may help to enhance corneal stromal adhesion and biocompatibility. Translational Relevance Improving the biocompatibility of the BK PMMA stem may improve long-term outcomes of implantation.
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Affiliation(s)
- Sina Sharifi
- Disruptive Technology Laboratory and Schepens Eye Research Institute, Massachusetts Eye and Ear; Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Mohammad Mirazul Islam
- Disruptive Technology Laboratory and Schepens Eye Research Institute, Massachusetts Eye and Ear; Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Hannah Sharifi
- Disruptive Technology Laboratory and Schepens Eye Research Institute, Massachusetts Eye and Ear; Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Rakibul Islam
- Department of Immunology, Oslo University Hospital, Rikshospitalet, University of Oslo, Oslo, Norway
| | - Per H Nilsson
- Department of Immunology, Oslo University Hospital, Rikshospitalet, University of Oslo, Oslo, Norway.,Linnaeus Center for Biomaterials Chemistry, Linnaeus University, Kalmar, Sweden
| | - Claes H Dohlman
- Disruptive Technology Laboratory and Schepens Eye Research Institute, Massachusetts Eye and Ear; Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Tom Eirik Mollnes
- Department of Immunology, Oslo University Hospital, Rikshospitalet, University of Oslo, Oslo, Norway.,Research Laboratory, Nordland Hospital, Bodø, Norway; Faculty of Health Sciences, K.G. Jebsen TREC, University of Tromsø, Tromsø, Norway.,Centre of Molecular Inflammation Research, Norwegian University of Science and Technology, Trondheim, Norway
| | - Eleftherios I Paschalis
- Disruptive Technology Laboratory and Schepens Eye Research Institute, Massachusetts Eye and Ear; Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - James Chodosh
- Disruptive Technology Laboratory and Schepens Eye Research Institute, Massachusetts Eye and Ear; Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
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Zhu YT, Li F, Zhang Y, Chen SY, Tighe S, Lin SY, Tseng SCG. HC-HA/PTX3 Purified From Human Amniotic Membrane Reverts Human Corneal Fibroblasts and Myofibroblasts to Keratocytes by Activating BMP Signaling. Invest Ophthalmol Vis Sci 2020; 61:62. [PMID: 32462202 PMCID: PMC7405802 DOI: 10.1167/iovs.61.5.62] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Purpose Fibrosis or scarring is a pathological outcome of wound healing and is characterized by terminally differentiated myofibroblasts. Heavy chain-hyaluronic acid/pentraxin 3 (HC-HA/PTX3) is a unique matrix component purified from amniotic membrane that exerts an anti-inflammatory effect. Herein, we investigate whether HC-HA/PTX3 can also exert an antiscarring effect. Methods Human corneal fibroblasts and myofibroblasts were seeded on plastic, immobilized HA or HC-HA/PTX3 or on plastic with or without soluble HA and HC-HA/PTX3 in DMEM+10% FBS, with or without AMD3100 or SB431542 in DMEM+ITS with or without transforming growth factor–β1 (TGF-β1). Transcript expression of keratocyte and signaling markers was determined by RT-qPCR. Immunostaining was performed to monitor cytolocalization of signaling markers and α-SMA. Western blotting was used to measure relative protein level. Results Human corneal fibroblasts and myofibroblasts cultured in or on HC-HA/PTX3, but not HA, were refrained from cytoplasmic expression of αSMA and nuclear translocation of pSMAD2/3 when challenged with exogenous TGF-β1. Such an antiscarring action by suppressing canonical TGF-β1 signaling was surprisingly accompanied by phenotypic reversal to keratocan-expressing keratocytes through activation of BMP signaling. Further investigation disclosed that such phenotypic reversal was initiated by cell aggregation mediated by SDF1-CXCR4 signaling highlighted by nuclear translocation of CXCR4 and upregulation of CXCR4 transcript and protein followed by activation of canonical BMP signaling. Conclusions These findings collectively provide mechanistic understanding explaining how amniotic membrane transplantation exerts an antiscarring action. In addition, HC-HA/PTX3 and derivatives may be developed into a new biologic to treat corneal blindness caused by stromal scar or opacity in the future.
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Espana EM, Birk DE. Composition, structure and function of the corneal stroma. Exp Eye Res 2020; 198:108137. [PMID: 32663498 PMCID: PMC7508887 DOI: 10.1016/j.exer.2020.108137] [Citation(s) in RCA: 92] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 06/29/2020] [Accepted: 06/30/2020] [Indexed: 12/13/2022]
Abstract
No other tissue in the body depends more on the composition and organization of the extracellular matrix (ECM) for normal structure and function than the corneal stroma. The precise arrangement and orientation of collagen fibrils, lamellae and keratocytes that occurs during development and is needed in adults to maintain stromal function is dependent on the regulated interaction of multiple ECM components that contribute to attain the unique properties of the cornea: transparency, shape, mechanical strength, and avascularity. This review summarizes the contribution of different ECM components, their structure, regulation and function in modulating the properties of the corneal stroma. Fibril forming collagens (I, III, V), fibril associated collagens with interrupted triple helices (XII and XIV), network forming collagens (IV, VI and VIII) as well as small leucine-rich proteoglycans (SLRP) expressed in the stroma: decorin, biglycan, lumican, keratocan, and fibromodulin are some of the ECM components reviewed in this manuscript. There are spatial and temporal differences in the expression of these ECM components, as well as interactions among them that contribute to stromal function. Unique regions within the stroma like Bowman's layer and Descemet's layer are discussed. To define the complexity of corneal stroma composition and structure as well as the relationship to function is a daunting task. Our knowledge is expanding, and we expect that this review provides a comprehensive overview of current knowledge, definition of gaps and suggests future research directions.
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Affiliation(s)
- Edgar M Espana
- Department of Molecular Pharmacology and Physiology, USA; Cornea, External Disease and Refractive Surgery, Department of Ophthalmology, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
| | - David E Birk
- Department of Molecular Pharmacology and Physiology, USA.
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Yam GHF, Riau AK, Funderburgh ML, Mehta JS, Jhanji V. Keratocyte biology. Exp Eye Res 2020; 196:108062. [PMID: 32442558 DOI: 10.1016/j.exer.2020.108062] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 05/01/2020] [Accepted: 05/04/2020] [Indexed: 12/12/2022]
Abstract
The study of corneal stromal keratocytes is motivated by its strong association with corneal health and visual function. They play a dominant role in the maintenance of corneal homeostasis and transparency through the production of collagens, proteoglycans and corneal crystallins. Trauma-induced apoptosis of keratocytes and replacement by fibroblasts and myofibroblasts disrupt the stromal matrix organization, resulting in corneal haze formation and vision loss. It is, therefore, important to understand the biology and behaviours of keratocytes and the associated stromal cell types (like fibroblasts, myofibroblasts, stromal stem cells) in wound healing, corneal pathologies (including keratoconus, keratitis, endothelial disorders) as well as different ophthalmic situations (such as collagen crosslinking/photodynamic treatment, keratoplasty and refractive surgery, and topical medications). The recent development of ex vivo propagation of keratocytes and stromal stem cells, and their translational applications, either via stromal injection or incorporated in bioscaffold, have been shown to restore the corneal transparency and regenerate native stromal tissue in animal models of corneal haze and other disorders.
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Affiliation(s)
- Gary H F Yam
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA.
| | - Andri K Riau
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore
| | | | - Jodhbir S Mehta
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore
| | - Vishal Jhanji
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA
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12
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Jeang L, Cha BJ, Birk DE, Espana EM. Endothelial-Stromal Communication in Murine and Human Corneas. Anat Rec (Hoboken) 2020; 303:1717-1726. [PMID: 32243086 DOI: 10.1002/ar.24393] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 12/22/2019] [Accepted: 12/31/2019] [Indexed: 12/13/2022]
Abstract
The purpose of this study is to identify and characterize interactions of corneal endothelial cells with the posterior stroma. Corneal endothelial-stromal interactions were examined in developing postnatal day 3 (P3) and mature postnatal day 30 (P30) C57BL/6 mice and adult human corneas. Flat mounts and cross-sections were studied using immunofluorescence microscopy. F-actin was labeled with phalloidin to evaluate cell processes traversing Descemet's membrane (DM). Dynamic cell-cell communication was evaluated with fluorescence recovery after photobleaching (FRAP) using calcein acetoxymethyl dye. Endothelial-stromal interactions were observed across the whole cornea transversing DM during early postnatal development (P3), while these interactions became restricted to the periphery in the mature murine cornea (P30). In adult human corneas, endothelial extensions through the DM were observed in the peripheral cornea. The pattern of FRAP in both mature mice and human central corneas demonstrated endothelial-endothelial cell communication. In contrast, in the human cornea 2, distinct patterns were observed consistent with endothelial-endothelial and stromal-endothelial communication. Endothelial-stromal interactions were observed in the entire cornea during early postnatal mouse corneas. This evidence of endothelial-posterior stromal contact contradicts the hypothesis that corneal endothelial cells are isolated from the stroma by the DM and provides direct data to support endothelial-stromal comunication that may directly influence posterior corneal structure and function. Anat Rec, 2020. © 2020 American Association for Anatomy.
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Affiliation(s)
- Lauren Jeang
- Cornea, External Disease and Refractive Surgery, Department of Ophthalmology, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Byeong J Cha
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - David E Birk
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Edgar M Espana
- Cornea, External Disease and Refractive Surgery, Department of Ophthalmology, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA.,Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
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13
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Tighe S, Mead OG, Lee A, Tseng SCG. Basic science review of birth tissue uses in ophthalmology. Taiwan J Ophthalmol 2020; 10:3-12. [PMID: 32309118 PMCID: PMC7158924 DOI: 10.4103/tjo.tjo_4_20] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 01/12/2020] [Indexed: 12/31/2022] Open
Abstract
The birth tissue is predominantly comprised of amniotic membrane (AM) and umbilical cord (UC), which share the same cell origin as the fetus. These versatile biological tissues have been used to treat a wide range of conjunctival and corneal conditions since 1940. The therapeutic benefits of the birth tissue stem from its anti-inflammatory and anti-scarring properties that orchestrate regenerative healing. Although the birth tissue also contains many cytokines, growth factors, and proteins, the heavy chain 1-hyaluronic acid/pentraxin 3 (HC-HA/PTX3) matrix has been identified to be a major active tissue component responsible for AM/UC's multifactorial therapeutic actions. HC-HA/PTX3 complex is abundantly present in fresh and cryopreserved AM/UC, but not in dehydrated tissue. In this review, we discuss the tissue anatomy, the molecular mechanism of action based on HC-HA/ PTX3 to explain their therapeutic potentials, and the various forms available in ophthalmology.
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Affiliation(s)
- Sean Tighe
- R&D Department, TissueTech Inc., Miami, Florida, USA
- Department of Ophthalmology, Herbert Wertheim College of Medicine, Florida International University, Miami, Florida, USA
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, USA
| | | | - Amy Lee
- R&D Department, TissueTech Inc., Miami, Florida, USA
| | - Scheffer C. G. Tseng
- R&D Department, TissueTech Inc., Miami, Florida, USA
- Ocular Surface Center and Ocular Surface Research Education Foundation, Miami, FL, USA
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14
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Fenner BJ, Yusoff NZBM, Fuest M, Zhou L, Bandeira F, Cajucom-Uy HY, Tan HK, Mehta JS, Yam GHF. A cellular and proteomic approach to assess proteins extracted from cryopreserved human amnion in the cultivation of corneal stromal keratocytes for stromal cell therapy. EYE AND VISION 2019; 6:30. [PMID: 31632999 PMCID: PMC6790058 DOI: 10.1186/s40662-019-0155-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 09/20/2019] [Indexed: 12/13/2022]
Abstract
Background Human corneal stromal keratocytes propagated in culture media supplemented with human amnion extract (AME) can correct early corneal haze in an animal model. Clinical application of cultivated keratocytes is limited by infectious disease screening before amnion products can be used in humans. It remains unclear if AME from cryopreserved versus fresh human amnion can support human keratocyte propagation, and which components of the extract promote keratocyte growth. Methods Three placentas were collected for the preparation of fresh and cryopreserved amnion tissues followed by homogenization and protein extraction. AME protein profiles were studied using isobaric tagging for relative and absolute quantitation (iTRAQ) proteomics. Enriched gene ontology (GO) terms and functional classes were identified. Primary human keratocytes from 4 donor corneas were cultured in media supplemented with fresh AME (F-AME) or cryopreserved AME (C-AME). Cell viability, proliferation and keratocyte marker expression were examined by confocal immunofluorescence and flow cytometry. Results AME proteomics revealed 1385 proteins with similar expression levels (between 0.5- and 2-fold) between F- and C-AME, while 286 proteins were reduced (less than 0.5-fold) in C-AME. Enriched GO term and biological pathway analysis showed that those proteins with comparable expression between F-AME and C-AME were involved in cell metabolism, epithelial-mesenchymal transition, focal adhesion, cell-extracellular matrix interaction, cell stress regulation and complement cascades. Human corneal stromal keratocytes cultured with F-AME or C-AME showed similar morphology and viability, while cell proliferation was mildly suppressed with C-AME (P > 0.05). Expression of aldehyde dehydrogenase 3A1 (ALDH3A1) and CD34 was similar in both cultures. Conclusion AME from cryopreserved amnion had limited influence on keratocyte culture. It is feasible to use protein extract from cryopreserved amnion to propagate human keratocytes for potential translational applications.
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Affiliation(s)
- Beau J Fenner
- 1Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, 20 College Road, The Academia, Discovery Tower Level 6, Singapore, 169856 Singapore.,2Singapore National Eye Centre, Singapore, Singapore
| | - Nur Zahirah B M Yusoff
- 1Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, 20 College Road, The Academia, Discovery Tower Level 6, Singapore, 169856 Singapore
| | - Matthias Fuest
- 1Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, 20 College Road, The Academia, Discovery Tower Level 6, Singapore, 169856 Singapore.,3Department of Ophthalmology, RWTH Aachen University, Aachen, Germany
| | - Lei Zhou
- 4Eye-Academic Clinical Programme, Duke-NUS Graduate Medical School, Singapore, Singapore.,5Proteomics Platform, Singapore Eye Research Institute, Singapore, Singapore
| | - Francisco Bandeira
- 1Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, 20 College Road, The Academia, Discovery Tower Level 6, Singapore, 169856 Singapore.,6Federal University of São Paulo, Sao Paulo, Brazil
| | | | - H K Tan
- 8Department of Obstetrics and Gynaecology, Singapore General Hospital, Singapore, Singapore
| | - Jodhbir S Mehta
- 1Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, 20 College Road, The Academia, Discovery Tower Level 6, Singapore, 169856 Singapore.,2Singapore National Eye Centre, Singapore, Singapore.,4Eye-Academic Clinical Programme, Duke-NUS Graduate Medical School, Singapore, Singapore
| | - Gary H F Yam
- 1Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, 20 College Road, The Academia, Discovery Tower Level 6, Singapore, 169856 Singapore.,4Eye-Academic Clinical Programme, Duke-NUS Graduate Medical School, Singapore, Singapore
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15
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Wilson SE, Medeiros CS, Santhiago MR. Pathophysiology of Corneal Scarring in Persistent Epithelial Defects After PRK and Other Corneal Injuries. J Refract Surg 2018; 34:59-64. [PMID: 29315443 PMCID: PMC5788463 DOI: 10.3928/1081597x-20171128-01] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Accepted: 11/20/2017] [Indexed: 12/25/2022]
Abstract
PURPOSE To analyze corneal persistent epithelial defects that occurred at 3 to 4 weeks after -4.50 diopter (D) photorefractive keratectomy (PRK) in rabbits and apply this pathophysiology to the treatment of persistent epithelial defects that occur after any corneal manipulations or diseases. METHODS Two of 168 corneas that had -4.50 D PRK to study epithelial basement membrane regeneration developed spontaneous persistent epithelial defects that did not heal at 3 weeks after PRK. These were studied with slit-lamp photographs, immunohistochemistry for the myofibroblast marker alpha-smooth muscle actin (α-SMA), and transmission electron microscopy. RESULTS Myofibroblasts developed at the stromal surface within the persistent epithelial defect and for a short distance peripheral to the leading edge of the epithelium. No normal epithelial basement membrane was detectable within the persistent epithelial defect or for up to 0.3 mm behind the leading edge of the epithelium, although epithelial basement membrane had normally regenerated in other areas of the zone ablated by an excimer laser where the epithelium healed promptly. CONCLUSIONS A persistent epithelial defect in the cornea results in the development of myofibroblasts and disordered extracellular matrix produced by these cells that together cause opacity within, and a short distance beyond, the persistent epithelial defect. Clinicians should treat persistent epithelial defects within 10 days of non-closure of the epithelium to facilitate epithelial healing to prevent long-term stromal scarring (fibrosis). [J Refract Surg. 2018;34(1):59-64.].
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16
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Kumar P, Satyam A, Cigognini D, Pandit A, Zeugolis DI. Low oxygen tension and macromolecular crowding accelerate extracellular matrix deposition in human corneal fibroblast culture. J Tissue Eng Regen Med 2017; 12:6-18. [PMID: 27592127 DOI: 10.1002/term.2283] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2015] [Revised: 07/30/2016] [Accepted: 08/26/2016] [Indexed: 12/13/2022]
Abstract
Development of implantable devices based on the principles of in vitro organogenesis has been hindered due to the prolonged time required to develop an implantable device. Herein we assessed the influence of serum concentration (0.5% and 10%), oxygen tension (0.5%, 2% and 20%) and macromolecular crowding (75 μg/ml carrageenan) in extracellular matrix deposition in human corneal fibroblast culture (3, 7 and 14 days). The highest extracellular matrix deposition was observed after 14 days in culture at 0.5% serum, 2% oxygen tension and 75 μg/ml carrageenan. These data indicate that low oxygen tension coupled with macromolecular crowding significantly accelerate the development of scaffold-free tissue-like modules. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Pramod Kumar
- Regenerative, Modular & Developmental Engineering Laboratory (REMODEL), Biosciences Research Building, National University of Ireland Galway (NUI Galway), Galway, Ireland.,Centre for Research in Medical Devices (CÚRAM), Biosciences Research Building, National University of Ireland Galway (NUI Galway), Galway, Ireland
| | - Abhigyan Satyam
- Regenerative, Modular & Developmental Engineering Laboratory (REMODEL), Biosciences Research Building, National University of Ireland Galway (NUI Galway), Galway, Ireland.,Centre for Research in Medical Devices (CÚRAM), Biosciences Research Building, National University of Ireland Galway (NUI Galway), Galway, Ireland
| | - Daniela Cigognini
- Regenerative, Modular & Developmental Engineering Laboratory (REMODEL), Biosciences Research Building, National University of Ireland Galway (NUI Galway), Galway, Ireland.,Centre for Research in Medical Devices (CÚRAM), Biosciences Research Building, National University of Ireland Galway (NUI Galway), Galway, Ireland
| | - Abhay Pandit
- Centre for Research in Medical Devices (CÚRAM), Biosciences Research Building, National University of Ireland Galway (NUI Galway), Galway, Ireland
| | - Dimitrios I Zeugolis
- Regenerative, Modular & Developmental Engineering Laboratory (REMODEL), Biosciences Research Building, National University of Ireland Galway (NUI Galway), Galway, Ireland.,Centre for Research in Medical Devices (CÚRAM), Biosciences Research Building, National University of Ireland Galway (NUI Galway), Galway, Ireland
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17
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Kumar P, Pandit A, Zeugolis DI. Progress in Corneal Stromal Repair: From Tissue Grafts and Biomaterials to Modular Supramolecular Tissue-Like Assemblies. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2016; 28:5381-5399. [PMID: 27028373 DOI: 10.1002/adma.201503986] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2015] [Revised: 12/31/2015] [Indexed: 06/05/2023]
Abstract
Corneal injuries and degenerative conditions have major socioeconomic consequences, given that in most cases, they result in blindness. In the quest of the ideal therapy, tissue grafts, biomaterials, and modular engineering approaches are under intense investigation. Herein, advancements and shortfalls are reviewed and future perspectives for these therapeutic strategies discussed.
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Affiliation(s)
- Pramod Kumar
- Regenerative, Modular & Developmental Engineering Laboratory (REMODEL), Biosciences Research Building, National University of Ireland Galway (NUI Galway), Galway, Ireland
- Center for Research in Medical Devices (CÚRAM), Biosciences Research Building, National University of Ireland Galway (NUI Galway), Galway, Ireland
| | - Abhay Pandit
- Center for Research in Medical Devices (CÚRAM), Biosciences Research Building, National University of Ireland Galway (NUI Galway), Galway, Ireland
| | - Dimitrios I Zeugolis
- Regenerative, Modular & Developmental Engineering Laboratory (REMODEL), Biosciences Research Building, National University of Ireland Galway (NUI Galway), Galway, Ireland
- Center for Research in Medical Devices (CÚRAM), Biosciences Research Building, National University of Ireland Galway (NUI Galway), Galway, Ireland
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18
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Tseng SCG. HC-HA/PTX3 Purified From Amniotic Membrane as Novel Regenerative Matrix: Insight Into Relationship Between Inflammation and Regeneration. Invest Ophthalmol Vis Sci 2016; 57:ORSFh1-8. [PMID: 27116665 PMCID: PMC4855828 DOI: 10.1167/iovs.15-17637] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 08/03/2015] [Indexed: 12/22/2022] Open
Abstract
PURPOSE Human limbal palisade of Vogt is an ideal model for studying and practicing regenerative medicine due to their accessibility. Nonresolving inflammation is a common manifestation of limbal stem cell deficiency, which is the major cause of corneal blindness, and presents as a threat to the success of transplanted limbal epithelial stem cells. Clinical studies have shown that the efficacy of transplantation of limbal epithelial stem cells can be augmented by transplantation of cryopreserved human amniotic membrane (AM), which exerts anti-inflammatory, antiscarring, and antiangiogenic action to promote wound healing. METHODS Review of published data to determine the molecular action mechanism explaining how AM exerts the aforementioned therapeutic actions. RESULTS From the water-soluble extract of cryopreserved AM, we have biochemically purified one novel matrix component termed heavy chain (HC)-hyaluronan (HA)/pentraxin 3 (PTX3) as the key relevant tissue characteristic responsible for the aforementioned AM's efficacy. Heavy chain-HA is a complex formed by a covalent linkage between HA and HC1 of inter-α-trypsin inhibitor (IαI) by tumor necrosis factor-stimulated gene-6 (TSG-6). This complex may then be tightly associated with PTX3 to form HC-HA/PTX3 complex. Besides exerting an anti-inflammatory, antiscarring, and antiangiogenic effects, HC-HA/PTX3 complex also uniquely maintains limbal niche cells to support the quiescence of limbal epithelial stem cells. CONCLUSIONS We envision that HC-HA/PTX3 purified from AM can be used as a unique substrate to refine ex vivo expansion of limbal epithelial stem cells by maintaining stem cell quiescence, self-renewal and fate decision. Furthermore, it can also be deployed as a platform to launch new therapeutics in regenerative medicine by mitigating nonresolving inflammation and reinforcing the well-being of stem cell niche.
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Affiliation(s)
- Scheffer C. G. Tseng
- The R&D Department of TissueTech Inc., Ocular Surface Center, and Ocular Surface Research and Education Foundation, Miami, Florida, United States
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19
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Tseng SCG, He H, Zhang S, Chen SY. Niche Regulation of Limbal Epithelial Stem Cells: Relationship between Inflammation and Regeneration. Ocul Surf 2016; 14:100-12. [PMID: 26769483 DOI: 10.1016/j.jtos.2015.12.002] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 12/17/2015] [Accepted: 12/24/2015] [Indexed: 02/07/2023]
Abstract
Human limbal palisades of Vogt are the ideal site for studying and practicing regenerative medicine due to their accessibility. Nonresolving inflammation in limbal stroma is common manifestation of limbal stem cell (SC) deficiency and presents as a threat to the success of transplanted limbal epithelial SCs. This pathologic process can be overcome by transplantation of cryopreserved human amniotic membrane (AM), which exerts anti-inflammatory, antiscarring and anti-angiogenic action to promote wound healing. To determine how AM might exert anti-inflammation and promote regeneration, we have purified a novel matrix, HC-HA/PTX3, responsible for the efficacy of AM efficacy. HC-HA complex is covalently formed by hyaluronan (HA) and heavy chain 1 (HC1) of inter-α-trypsin inhibitor by the catalytic action of tumor necrosis factor-stimulated gene-6 (TSG-6) and are tightly associated with pentraxin 3 (PTX3) to form HC-HA/PTX3. In vitro reconstitution of the limbal niche can be established by reunion between limbal epithelial progenitors and limbal niche cells on different substrates. In 3-dimensional Matrigel, clonal expansion indicative of SC renewal is correlated with activation of canonical Wnt signaling and suppression of canonical bone morphogenetic protein (BMP) signaling. In contrast, SC quiescence can be achieved in HC-HA/PTX3 by activation of canonical BMP signaling and non-canonical planar cell polarity (PCP) Wnt signaling, but suppression of canonical Wnt signaling. HC-HA/PTX3 is a novel matrix mitigating nonresolving inflammation and restoring SC quiescence in the niche for various applications in regenerative medicine.
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Affiliation(s)
- Scheffer C G Tseng
- R&D Department, TissueTech, Inc., Ocular Surface Center, and Ocular Surface Research and Education Foundation, Miami, Florida, USA.
| | - Hua He
- R&D Department, TissueTech, Inc., Ocular Surface Center, and Ocular Surface Research and Education Foundation, Miami, Florida, USA
| | - Suzhen Zhang
- R&D Department, TissueTech, Inc., Ocular Surface Center, and Ocular Surface Research and Education Foundation, Miami, Florida, USA
| | - Szu-Yu Chen
- R&D Department, TissueTech, Inc., Ocular Surface Center, and Ocular Surface Research and Education Foundation, Miami, Florida, USA
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20
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Kumar P, Satyam A, Fan X, Rochev Y, Rodriguez BJ, Gorelov A, Joshi L, Raghunath M, Pandit A, Zeugolis DI. Accelerated Development of Supramolecular Corneal Stromal-Like Assemblies from Corneal Fibroblasts in the Presence of Macromolecular Crowders. Tissue Eng Part C Methods 2015; 21:660-70. [PMID: 25535812 DOI: 10.1089/ten.tec.2014.0387] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Tissue engineering by self-assembly uses the cells' secretome as a regeneration template and biological factory of trophic factors. Despite the several advantages that have been witnessed in preclinical and clinical settings, the major obstacle for wide acceptance of this technology remains the tardy extracellular matrix formation. In this study, we assessed the influence of macromolecular crowding (MMC)/excluding volume effect, a biophysical phenomenon that accelerates thermodynamic activities and biological processes by several orders of magnitude, in human corneal fibroblast (HCF) culture. Our data indicate that the addition of negatively charged galactose derivative (carrageenan) in HCF culture, even at 0.5% serum, increases by 12-fold tissue-specific matrix deposition, while maintaining physiological cell morphology and protein/gene expression. Gene analysis indicates that a glucose derivative (dextran sulfate) may drive corneal fibroblasts toward a myofibroblast lineage. Collectively, these results indicate that MMC may be suitable not only for clinical translation and commercialization of tissue engineering by self-assembly therapies, but also for the development of in vitro pathophysiology models.
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Affiliation(s)
- Pramod Kumar
- 1 Network of Excellence for Functional Biomaterials (NFB), Bioscience Research Building, National University of Ireland Galway (NUI Galway) , Galway, Ireland
| | - Abhigyan Satyam
- 1 Network of Excellence for Functional Biomaterials (NFB), Bioscience Research Building, National University of Ireland Galway (NUI Galway) , Galway, Ireland
| | - Xingliang Fan
- 1 Network of Excellence for Functional Biomaterials (NFB), Bioscience Research Building, National University of Ireland Galway (NUI Galway) , Galway, Ireland
| | - Yury Rochev
- 1 Network of Excellence for Functional Biomaterials (NFB), Bioscience Research Building, National University of Ireland Galway (NUI Galway) , Galway, Ireland
| | - Brian J Rodriguez
- 2 Conway Institute of Biomolecular & Biomedical Research, University College Dublin , Dublin, Ireland
| | - Alexander Gorelov
- 3 School of Chemistry & Chemical Biology, University College Dublin , Dublin, Ireland
| | - Lokesh Joshi
- 4 Alimentary Glycoscience Research Cluster, NUI Galway , Galway, Ireland
| | - Michael Raghunath
- 5 Department of Bioengineering, Faculty of Engineering, National University of Singapore , Singapore, Singapore .,6 Tissue Engineering Programme, Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore , Singapore, Singapore
| | - Abhay Pandit
- 1 Network of Excellence for Functional Biomaterials (NFB), Bioscience Research Building, National University of Ireland Galway (NUI Galway) , Galway, Ireland
| | - Dimitrios I Zeugolis
- 1 Network of Excellence for Functional Biomaterials (NFB), Bioscience Research Building, National University of Ireland Galway (NUI Galway) , Galway, Ireland
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21
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Macromolecularly crowded in vitro microenvironments accelerate the production of extracellular matrix-rich supramolecular assemblies. Sci Rep 2015; 5:8729. [PMID: 25736020 PMCID: PMC4348624 DOI: 10.1038/srep08729] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 01/27/2015] [Indexed: 12/13/2022] Open
Abstract
Therapeutic strategies based on the principles of tissue engineering by self-assembly put forward the notion that functional regeneration can be achieved by utilising the inherent capacity of cells to create highly sophisticated supramolecular assemblies. However, in dilute ex vivo microenvironments, prolonged culture time is required to develop an extracellular matrix-rich implantable device. Herein, we assessed the influence of macromolecular crowding, a biophysical phenomenon that regulates intra- and extra-cellular activities in multicellular organisms, in human corneal fibroblast culture. In the presence of macromolecules, abundant extracellular matrix deposition was evidenced as fast as 48 h in culture, even at low serum concentration. Temperature responsive copolymers allowed the detachment of dense and cohesive supramolecularly assembled living substitutes within 6 days in culture. Morphological, histological, gene and protein analysis assays demonstrated maintenance of tissue-specific function. Macromolecular crowding opens new avenues for a more rational design in engineering of clinically relevant tissue modules in vitro.
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22
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Kobayashi T, Shiraishi A, Hara Y, Kadota Y, Yang L, Inoue T, Shirakata Y, Ohashi Y. Stromal-epithelial interaction study: The effect of corneal epithelial cells on growth factor expression in stromal cells using organotypic culture model. Exp Eye Res 2015; 135:109-17. [PMID: 25682729 DOI: 10.1016/j.exer.2015.02.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 02/09/2015] [Accepted: 02/11/2015] [Indexed: 11/29/2022]
Abstract
Interactions between stromal and epithelial cells play important roles in the development, homeostasis, and pathological conditions of the cornea. Soluble cytokines are critical factors in stromal-epithelial interactions, and growth factors secreted from corneal stromal cells contribute to the regulation of proliferation and differentiation of corneal epithelial cells (CECs). However, the manner in which the expression of growth factors is regulated in stromal cells has not been completely determined. To study stromal-epithelial cell interactions, we used an organotypic culture model. Human or rabbit CECs (HCECs or RCECs) were cultured on amniotic membranes placed on human corneal fibroblasts (HCFs) embedded in a collagen gel. The properties of the organotypic culture were examined by hematoxylin-eosin staining and immunofluorescence. In the organotypic culture, HCECs or RCECs were stratified into two-three layers after five days and five-seven layers after nine days. However, stratification was not observed when the HCECs were seeded on a collagen gel without fibroblasts. K3/K12 were expressed on day 9. The HCF-embedded collagen gels were collected on days 3, 5, or 9 after seeding the RCECs, and mRNA expression of growth factors FGF7, HGF, NGF, EGF, TGF-α, SCF, TGF-β1, TGF-β2, and TGF-β3 were quantified by real-time PCR. mRNA expression of the growth factors in HCFs cultured with RCECs were compared with those cultured without RCECs, as well as in monolayer cultures. mRNA expression of TGF-α was markedly increased in HCFs cultured with RCECs. However, mRNA expression of the TGF-β family was suppressed in HCFs cultured with RCECs. Principal component analysis revealed that mRNA expression of the growth factors in HCFs were generally similar when they were cultured with RCECs. In organotypic cultures, the morphological changes in the CECs and the expression patterns of the growth factors in the stromal cells clearly demonstrated stromal-epithelial cell interactions, and the results suggest that stromal cells and epithelial cells may act in concert in the cornea.
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Affiliation(s)
- Takeshi Kobayashi
- Department of Ophthalmology and Regenerative Medicine, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan; Department of Stem Cell Biology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan
| | - Atsushi Shiraishi
- Department of Ophthalmology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan; Department of Stem Cell Biology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan.
| | - Yuko Hara
- Department of Ophthalmology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan
| | - Yuko Kadota
- Department of Ophthalmology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan
| | - Lujun Yang
- Department of Dermatology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan
| | - Tomoyuki Inoue
- Department of Ophthalmology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan
| | - Yuji Shirakata
- Department of Dermatology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan
| | - Yuichi Ohashi
- Department of Ophthalmology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan; Department of Infectious Diseases, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan
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23
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Yam GHF, Yusoff NZBM, Kadaba A, Tian D, Myint HH, Beuerman RW, Zhou L, Mehta JS. Ex Vivo Propagation of Human Corneal Stromal "Activated Keratocytes" for Tissue Engineering. Cell Transplant 2014; 24:1845-61. [PMID: 25291523 DOI: 10.3727/096368914x685069] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Keratoconus is a corneal disorder characterized by a thinning of stromal tissue, and the affected patients have induced astigmatism and visual impairment. It is associated with a loss of corneal stromal keratocytes (CSKs). Hence, reconstructing stromal tissue with autologous CSK replacement can be a viable alternative to corneal transplantation, which is restricted by the global donor material shortage and graft rejection. Human CSKs are normally quiescent and express unique markers, like aldehyde dehydrogenases and keratocan. In serum culture, they proliferate, but lose their characteristic phenotype and become stromal fibroblasts. Here we report a novel culture cocktail to ex vivo propagate and maintain CSKs. Primary human CSKs were obtained from adult donors and cultured with soluble human amnion stromal extract (ASE), rho-associated coiled-coil-forming protein serine/threonine kinase inhibitor Y-27632, and insulin-like growth factor-1 (collectively named as ERI). Protein profiling using mass spectrometry followed by MetaCore™ pathway analysis predicted that ASE proteins might participate in transforming growth factor-β (TGF-β) signaling and fibroblast development, cell adhesion, extracellular matrix remodeling, and immune response. In culture with 0.5% fetal bovine serum and ERI, the population of "activated keratocytes" was expanded. They had much lowered expression of both keratocyte and fibroblast markers, suppressed TGF-β-mediated Smad2/3 activation, and lacked fibroblast-mediated collagen contractibility. These "activated keratoctyes" could be propagated for six to eight passages ex vivo, and they regained CSK-specific dendritic morphology and gene marker expression, including aldehyde dehydrogenases, lumican, and keratocan biosynthesis, expression, and secretion when returned to serum-depleted ERI condition. This novel cocktail maintained human CSKs in both adherent and suspension cultures with proper keratocyte features and without the transformation to stromal fibroblasts. Thus, human CSKs can be ex vivo propagated as transient "activated keratocytes." This could provide sufficient number of genuine CSKs for corneal tissue engineering.
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Affiliation(s)
- Gary Hin-Fai Yam
- Tissue Engineering and Stem Cell Group, Singapore Eye Research Institute, Singapore
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Liu J, Sheha H, Fu Y, Liang L, Tseng SC. Update on amniotic membrane transplantation. EXPERT REVIEW OF OPHTHALMOLOGY 2014; 5:645-661. [PMID: 21436959 DOI: 10.1586/eop.10.63] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cryopreserved amniotic membrane modulates adult wound healing by promoting epithelialization while suppressing stromal inflammation, angiogenesis and scarring. Such clinical efficacies of amniotic membrane transplantation have been reported in several hundred publications for a wide spectrum of ophthalmic indications. The success of the aforementioned therapeutic actions prompts investigators to use amniotic membrane as a surrogate niche to achieve ex vivo expansion of ocular surface epithelial progenitor cells. Further investigation into the molecular mechanism whereby amniotic membrane exerts its actions will undoubtedly reveal additional applications in the burgeoning field of regenerative medicine. This article will focus on recent advances in amniotic membrane transplantation and expand to cover its clinical uses beyond the ocular surface.
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Affiliation(s)
- Jingbo Liu
- Ocular Surface Center, 7000 SW, 97 Avenue, Suite 213, Miami, FL 33173, USA
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Lai JY. Interrelationship between cross-linking structure, molecular stability, and cytocompatibility of amniotic membranes cross-linked with glutaraldehyde of varying concentrations. RSC Adv 2014. [DOI: 10.1039/c4ra01930j] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Chemical cross-linker concentration has a marked influence on the interrelationship between cross-linking structure, molecular stability, and cytocompatibility of a glutaraldehyde-treated amniotic membrane for a limbal stem cell niche.
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Affiliation(s)
- Jui-Yang Lai
- Institute of Biochemical and Biomedical Engineering
- Chang Gung University
- Taoyuan 33302, Republic of China
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Guan L, Tian P, Ge H, Tang X, Zhang H, Du L, Liu P. Chitosan-functionalized silk fibroin 3D scaffold for keratocyte culture. J Mol Histol 2013; 44:609-18. [PMID: 23636607 DOI: 10.1007/s10735-013-9508-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 04/17/2013] [Indexed: 12/13/2022]
Abstract
The goal of this study was to evaluate the potential suitability of an artificial membrane composed of silk fibroin (SF) functionalized by different ratios of chitosan (CS) as a substrate for the stroma of the cornea. Keratocytes were cultured on translucent membranes made of SF and CS with different ratios. The biophysical properties of the silk fibroin and chitosan (SF/CS) membrane were examined. The SF/CS showed tensile strengths that increased as the CS concentration increased, but the physical and mechanical properties of chitosan-functionalized silk fibroin scaffolds weakened significantly compared with those of native corneas. The resulting cell scaffolds were evaluated using western blot in addition to light and electron microscopy. The cell attachment and proliferation on the scaffold were similar to those on a plastic plate. Keratocytes cultured in serum on SF/CS exhibited stellate morphology along with a marked increase in the expression of keratocan compared with identical cultures on tissue culture plastics. The biocompatibility was tested by transplanting the acellular membrane into rabbit corneal stromal pockets. There was no inflammatory complication detected at any time point on the macroscopic level. Taken together, these results indicate that SF/CS holds promise as a substrate for corneal reconstruction.
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Affiliation(s)
- Linan Guan
- Eye Hospital, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Harbin, 150001, People's Republic of China
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Identification of keratocyte-like cells differentiated from circulating bone marrow-derived cells in the mouse cornea. Med Mol Morphol 2013; 46:233-8. [PMID: 23529138 DOI: 10.1007/s00795-013-0031-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 12/04/2012] [Indexed: 12/13/2022]
Abstract
Bone marrow (BM)-derived stem cells have the potential to differentiate into multiple lineages of tissue resident cells. BM-derived cells have been detected in the mouse cornea, but most of these cells were found to be CD45(+) or CD11b(+) immunocompetent cells. Although some BM-derived cells in the cornea were negative for these cell surface markers, it has remained unclear whether cells of BM origin can differentiate into corneal resident cells. To address this issue, we subjected wild-type mice that had been exposed to a lethal dose of radiation to intravenous injection with BM cells from green fluorescent protein (GFP) transgenic mice. Two months after cell transplantation, fluorescence microscopy revealed the presence of numerous GFP(+) cells throughout the cornea, with intense GFP fluorescence being apparent around the limbal region. Immunohistofluorescence analysis of corneal cross-sections revealed that most of the BM-derived GFP(+) cells expressed CD45 or CD11b, although a few GFP(+) cells were negative for these markers. Immunostaining of individual cells isolated from the corneal stroma, however, showed that a small proportion (~1 %) of GFP(+) BM-derived cells expressed the keratocyte-specific proteoglycan keratocan. Our results suggest that BM-derived cells introduced intravenously are able to differentiate into resident cells of the corneal stroma.
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Wilson SL, El Haj AJ, Yang Y. Control of scar tissue formation in the cornea: strategies in clinical and corneal tissue engineering. J Funct Biomater 2012; 3:642-87. [PMID: 24955637 PMCID: PMC4031002 DOI: 10.3390/jfb3030642] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2012] [Revised: 08/27/2012] [Accepted: 08/30/2012] [Indexed: 12/13/2022] Open
Abstract
Corneal structure is highly organized and unified in architecture with structural and functional integration which mediates transparency and vision. Disease and injury are the second most common cause of blindness affecting over 10 million people worldwide. Ninety percent of blindness is permanent due to scarring and vascularization. Scarring caused via fibrotic cellular responses, heals the tissue, but fails to restore transparency. Controlling keratocyte activation and differentiation are key for the inhibition and prevention of fibrosis. Ophthalmic surgery techniques are continually developing to preserve and restore vision but corneal regression and scarring are often detrimental side effects and long term continuous follow up studies are lacking or discouraging. Appropriate corneal models may lead to a reduced need for corneal transplantation as presently there are insufficient numbers or suitable tissue to meet demand. Synthetic optical materials are under development for keratoprothesis although clinical use is limited due to implantation complications and high rejection rates. Tissue engineered corneas offer an alternative which more closely mimic the morphological, physiological and biomechanical properties of native corneas. However, replication of the native collagen fiber organization and retaining the phenotype of stromal cells which prevent scar-like tissue formation remains a challenge. Careful manipulation of culture environments are under investigation to determine a suitable environment that simulates native ECM organization and stimulates keratocyte migration and generation.
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Affiliation(s)
- Samantha L Wilson
- Institute for Science and Technology in Medicine, School of Medicine, Keele University, Staffordshire, ST4 7QB, UK.
| | - Alicia J El Haj
- Institute for Science and Technology in Medicine, School of Medicine, Keele University, Staffordshire, ST4 7QB, UK.
| | - Ying Yang
- Institute for Science and Technology in Medicine, School of Medicine, Keele University, Staffordshire, ST4 7QB, UK.
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Dellett M, Hu W, Papadaki V, Ohnuma SI. Small leucine rich proteoglycan family regulates multiple signalling pathways in neural development and maintenance. Dev Growth Differ 2012; 54:327-40. [DOI: 10.1111/j.1440-169x.2012.01339.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Margaret Dellett
- University College London (UCL) Institute of Ophthalmology; UCL; London; UK
| | - Wanzhou Hu
- University College London (UCL) Institute of Ophthalmology; UCL; London; UK
| | - Vasiliki Papadaki
- University College London (UCL) Institute of Ophthalmology; UCL; London; UK
| | - Shin-ichi Ohnuma
- University College London (UCL) Institute of Ophthalmology; UCL; London; UK
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30
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Wilson SE. Corneal myofibroblast biology and pathobiology: generation, persistence, and transparency. Exp Eye Res 2012; 99:78-88. [PMID: 22542905 DOI: 10.1016/j.exer.2012.03.018] [Citation(s) in RCA: 145] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Revised: 03/12/2012] [Accepted: 03/28/2012] [Indexed: 02/06/2023]
Abstract
Important advances have led to a better understanding of the biology and pathobiology of corneal myofibroblasts and their generation after surgery, injury, infection and disease. Transforming growth factor (TGF) beta, along with platelet-derived growth factor (PDGF) and interleukin (IL)-1, has been shown to regulate myofibroblast development and death in in-vitro and in-situ animal models. The myofibroblast precursor cells regulated by these cytokines include both keratocyte-derived and bone marrow-derived cells. Cytokines that promote and maintain myofibroblasts associated with late haze after photorefractive keratectomy are modulated in part by the epithelial basement membrane functioning as barrier between the epithelium and stroma. Structural and functional defects in the basement membrane likely lead to prolonged elevation of TGFβ, and perhaps other cytokine, levels in the stroma necessary to promote differentiation of myofibroblasts. Conversely, repair of the epithelial basement membrane likely leads to a decrease in stromal TGFβ levels and apoptosis of myofibroblasts. Repopulating keratocytes subsequently reorganize the associated fibrotic extracellular matrix deposited in the anterior stroma by the myofibroblasts. Investigations of myofibroblast biology are likely to lead to safer pharmacological modulators of corneal wound healing and transparency.
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Affiliation(s)
- Steven E Wilson
- The Cole Eye Institute, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
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Effect of Toll-like receptor 2 and 4 of corneal fibroblasts on cytokine expression with co-cultured antigen presenting cells. Cytokine 2011; 56:265-71. [PMID: 21820318 DOI: 10.1016/j.cyto.2011.07.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Revised: 04/29/2011] [Accepted: 07/05/2011] [Indexed: 11/20/2022]
Abstract
Keratocytes are the first component to contact ocular pathogens when the epithelial barrier breaks down and the emerging evidences indicated keratocytes appeared to be one of the corneal cellular immune components. Little is known about the role of Toll-like receptors (TLRs) in keratocytes, although it has been well documented that keratocytes constitutively express various TLRs including TLR2 and TLR4. In this in vitro study, the authors focused on the role of keratocytes in corneal innate immune system and cross-talk of keratocytes with resident antigen presenting cells (APCs), especially through TLR2 and TLR4. Primary cultivated keratocytes (corneal fibroblasts) from C57BL/6 mice per se actively secreted pro-inflammatory cytokines, especially interleukin (IL)-6, with a dose-dependent manner in response to Pam3CSK4 or lipopolysaccharide (LPS) challenge. With co-culture of corneal fibroblasts with APCs per se, secretion of IL-6 and tumor necrosis factor (TNF)-α was markedly increased and it was counterbalanced by concurrent increase in IL-10 and tumor growth factor-β1. After Pam3CSK4 or LPS stimulation, this cytokine balance was completely broken down by overwhelming amplification of IL-6 and TNF-α secretion, especially in co-culture of corneal fibroblasts with macrophages, rather than with dendritic cells. Using corneal fibroblasts from TLR2 or TLR4 knockout mice, we could find the reversal of Pam3CSK4 or LPS-responsive dose-dependent increment in IL-6 and TNF-α. These results implied that corneal fibroblasts and their TLRs could be key components for the ocular homeostasis and pathogen-associated ocular innate immunity.
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Shay E, He H, Sakurai S, Tseng SCG. Inhibition of angiogenesis by HC·HA, a complex of hyaluronan and the heavy chain of inter-α-inhibitor, purified from human amniotic membrane. Invest Ophthalmol Vis Sci 2011; 52:2669-78. [PMID: 21228375 DOI: 10.1167/iovs.10-5888] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
PURPOSE To determine whether antiangiogenic action of the amniotic membrane (AM) can be mediated by HC·HA, a covalent complex of hyaluronan (HA) and the heavy chain (HC) of inter-α-inhibitor, purified from AM soluble extract. METHODS HC·HA action on viability, proliferation, attachment, death, migration, and differentiation of human umbilical vein endothelial cells (HUVECs) and neovascularization in chicken chorioallantoic membrane (CAM) was examined by MTT assay, BrdU labeling, cell proliferation assay, cell death detection ELISA, transwell assay, tube formation assay, and CAM assay. RESULTS HC·HA suppressed HUVEC viability more significantly than HA and AM stromal extract, and such suppression was not mediated by CD44. HC·HA also caused HUVECs to become small and rounded, with a decrease in spreading and filamentous actin. Without promoting cell detachment or death, HC·HA dose dependently inhibited proliferation (IC(50), 2.3 μg/mL) and was 100-fold more potent than HA. Migration triggered by VEGF and tube formation was also significantly inhibited by HC·HA. Purified HC·HA did not contain PEDF and TSP-1 but did contain IGFBP-1 and platelet factor 4 while significantly suppressing neovascularization in CAM. CONCLUSIONS The antiangiogenic activity of HC·HA might explain why AM is developmentally avascular and how AM might exert an antiangiogenic action when transplanted to the ocular surface, and it might indicate a potential therapeutic effect of HC·HA in diseases manifesting pathogenic angiogenesis. Roles of IGFBP-1 and platelet factor 4 in HC·HA antiangiogenic action warrant further investigation.
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Strzalka-Mrozik B, Stanik-Walentek A, Kapral M, Kowalczyk M, Adamska J, Gola J, Mazurek U. Differential expression of transforming growth factor-beta isoforms in bullous keratopathy corneas. Mol Vis 2010; 16:161-6. [PMID: 20142847 PMCID: PMC2817012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Accepted: 02/02/2010] [Indexed: 11/14/2022] Open
Abstract
PURPOSE The aim of this study was to investigate transcriptional activities of genes encoding transforming growth factor (TGF)-beta isoforms in bullous keratopathy corneas. METHODS The study group consisted of 45 patients with bullous keratopathy (22 females and 23 males). The control group included 45 corneal donors (21 females and 24 males). Quantification of TGF-beta1, TGF-beta2, and TGF-beta3 mRNAs was performed by real-time quantitative reverse transcription PCR (QRT-PCR). RESULTS TGF-beta1, TGF-beta2, and TGF-beta3 mRNAs were detected in both normal and pseudophakic bullous keratopathy (PBK) corneas. We found significantly lower transcriptional activity of TGF-beta3 mRNA in bullous keratopathy corneas compared to normal tissues. TGF-beta1 and TGF-beta2 expressions were at the same level in both PBK and healthy corneas. CONCLUSIONS Downregulation of TGF-beta3 gene expression may play a significant role in molecular changes observed in bullous keratopathy.
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Affiliation(s)
| | | | - Malgorzata Kapral
- Department of Biochemistry, Medical University of Silesia, Sosnowiec, Poland
| | - Malgorzata Kowalczyk
- Department of Medical Genetics, Medical University of Silesia, Sosnowiec, Poland
| | - Jolanta Adamska
- Department of Molecular Biology, Medical University of Silesia, Sosnowiec, Poland
| | - Joanna Gola
- Department of Molecular Biology, Medical University of Silesia, Sosnowiec, Poland
| | - Urszula Mazurek
- Department of Molecular Biology, Medical University of Silesia, Sosnowiec, Poland
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Chen YH, Wang IJ, Young TH. Formation of keratocyte spheroids on chitosan-coated surface can maintain keratocyte phenotypes. Tissue Eng Part A 2009; 15:2001-13. [PMID: 19292684 DOI: 10.1089/ten.tea.2008.0251] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Corneal keratocytes have been reported to be able to form spheroids that can preserve their phenotypes after being seeded back onto tissue culture plate in specific culture media. In this study, we found that keratocytes could also form spheroids on a bioengineered material, chitosan-coated surface, with 10% horse serum and Dulbecco's modified Eagle's medium. Under scanning electron microscopy observation, the cells in the spheroids were found to adhere each other tightly, and the cellular boundary could not be distinguished. They could return to a dendritic (keratocyte) morphology and proliferate after they were seeded back onto tissue culture plate. Immunocytochemistry was used to characterize these cells. Reverse transcription-polymerase chain reaction revealed that keratocytes in the spheroids were not from the PAX-6-positive progenitor cells. Further, the results of the seeding density and the number of spheroids formation, cell viability (MTT) assays, negative staining of Ki-67, and Live/Dead assay suggested that the spheroids were from cell aggregation instead of cell proliferation. Cells in the spheroids maintained phenotypes and functions characteristic of keratocytes, as seen by reverse transcription-polymerase chain reaction, collagen gel contraction assay, and challenges of keratocytes with transforming growth factor-beta1. Our results showed that corneal keratocytes could form spheroids on a chitosan-coated surface and maintain a keratocyte phenotype. However, such keratocyte spheroids do not proliferate and cannot withstand transforming growth factor-beta from myofibroblast differentiation.
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Affiliation(s)
- Yi-Hsin Chen
- Institute of Polymer Science and Engineering, College of Engineering, National Taiwan University , Taipei, Taiwan
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Scimè A, Desrosiers J, Trensz F, Palidwor GA, Caron AZ, Andrade-Navarro MA, Grenier G. Transcriptional profiling of skeletal muscle reveals factors that are necessary to maintain satellite cell integrity during ageing. Mech Ageing Dev 2009; 131:9-20. [PMID: 19913570 DOI: 10.1016/j.mad.2009.11.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Revised: 10/07/2009] [Accepted: 11/04/2009] [Indexed: 01/04/2023]
Abstract
Skeletal muscle ageing is characterized by faulty degenerative/regenerative processes that promote the decline of its mass, strength, and endurance. In this study, we used a transcriptional profiling method to better understand the molecular pathways and factors that contribute to these processes. To more appropriately contrast the differences in regenerative capacity of old muscle, we compared it with young muscle, where robust growth and efficient myogenic differentiation is ongoing. Notably, in old mice, we found a severe deficit in satellite cells activation. We performed expression analyses on RNA from the gastrocnemius muscle of young (3-week-old) and old (24-month-old) mice. The differential expression highlighted genes that are involved in the efficient functioning of satellite cells. Indeed, the greatest number of up-regulated genes in young mice encoded components of the extracellular matrix required for the maintenance of the satellite cell niche. Moreover, other genes included Wnt inhibitors (Wif1 and Sfrp2) and Notch activator (Dner), which are putatively involved in the interconnected signalling networks that control satellite cell function. The widespread expression differences for inhibitors of TGFbeta signalling further emphasize the shortcomings in satellite cell performance. Therefore, we draw attention to the breakdown of features required to maintain satellite cell integrity during the ageing process.
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Affiliation(s)
- Anthony Scimè
- Research Centre on Aging, Université de Sherbrooke, Sherbrooke, QC, Canada
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Pot SA, Liliensiek SJ, Myrna KE, Bentley E, Jester JV, Nealey PF, Murphy CJ. Nanoscale topography-induced modulation of fundamental cell behaviors of rabbit corneal keratocytes, fibroblasts, and myofibroblasts. Invest Ophthalmol Vis Sci 2009; 51:1373-81. [PMID: 19875665 DOI: 10.1167/iovs.09-4074] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Keratocyte-to-myofibroblast differentiation is a key factor in corneal wound healing. The purpose of this study was to determine the influence of environmental nanoscale topography on keratocyte, fibroblast, and myofibroblast cell behavior. METHODS Primary rabbit corneal keratocytes, fibroblasts, and myofibroblasts were seeded onto planar polyurethane surfaces with six patterned areas, composed of anisotropically ordered grooves and ridges with a 400-, 800-, 1200-, 1600-, 2000-, and 4000-nm pitch (pitch = groove + ridge width). After 24 hours cells were fixed, stained, imaged, and analyzed for cell shape and orientation. For migration studies, cells on each patterned surface were imaged every 10 minutes for 12 hours, and individual cell trajectories and migration rates were calculated. RESULTS Keratocytes, fibroblasts, and myofibroblasts aligned and elongated to pitch sizes larger than 1000 nm. A lower limit to the topographic feature sizes that the cells responded to was identified for all three phenotypes, with a transition zone around the 800- to 1200-nm pitch size. Fibroblasts and myofibroblasts migrated parallel to surface ridges larger than 1000 nm but lacked directional guidance on submicron and nanoscale topographic features and on planar surfaces. Keratocytes remained essentially immobile. CONCLUSIONS Corneal stromal cells elongated, aligned, and migrated, differentially guided by substratum topographic features. All cell types failed to respond to topographic features approximating the dimensions of individual stromal fibers. These findings contribute to our understanding of corneal stromal cell biology in health and disease and their interaction with biomaterials and their native extracellular matrix.
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Affiliation(s)
- Simon A Pot
- Department of Surgical Sciences, School of Veterinary Medicine, and
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Schultz GS, Wysocki A. Interactions between extracellular matrix and growth factors in wound healing. Wound Repair Regen 2009; 17:153-62. [PMID: 19320882 DOI: 10.1111/j.1524-475x.2009.00466.x] [Citation(s) in RCA: 711] [Impact Index Per Article: 47.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Dynamic interactions between growth factors and extracellular matrix (ECM) are integral to wound healing. These interactions take several forms that may be categorized as direct or indirect. The ECM can directly bind to and release certain growth factors (e.g., heparan sulfate binding to fibroblast growth factor-2), which may serve to sequester and protect growth factors from degradation, and/or enhance their activity. Indirect interactions include binding of cells to ECM via integrins, which enables cells to respond to growth factors (e.g., integrin binding is necessary for vascular endothelial growth factor-induced angiogenesis) and can induce growth factor expression (adherence of monocytes to ECM stimulates synthesis of platelet-derived growth factor). Additionally, matrikines, or subcomponents of ECM molecules, can bind to cell surface receptors in the cytokine, chemokine, or growth factor families and stimulate cellular activities (e.g., tenascin-C and laminin bind to epidermal growth factor receptors, which enhances fibroblast migration). Growth factors such as transforming growth factor-beta also regulate the ECM by increasing the production of ECM components or enhancing synthesis of matrix degrading enzymes. Thus, the interactions between growth factors and ECM are bidirectional. This review explores these interactions, discusses how they are altered in difficult to heal or chronic wounds, and briefly considers treatment implications.
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Affiliation(s)
- Gregory S Schultz
- Department of Obstetrics and Gynecology, University of Florida, Gainesville, 32610-0294, USA.
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He H, Li W, Tseng DY, Zhang S, Chen SY, Day AJ, Tseng SCG. Biochemical characterization and function of complexes formed by hyaluronan and the heavy chains of inter-alpha-inhibitor (HC*HA) purified from extracts of human amniotic membrane. J Biol Chem 2009; 284:20136-46. [PMID: 19491101 PMCID: PMC2740440 DOI: 10.1074/jbc.m109.021881] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Indexed: 01/01/2023] Open
Abstract
Clinically, amniotic membrane (AM) suppresses inflammation, scarring, and angiogenesis. AM contains abundant hyaluronan (HA) but its function in exerting these therapeutic actions remains unclear. Herein, AM was extracted sequentially with buffers A, B, and C, or separately by phosphate-buffered saline (PBS) alone. Agarose gel electrophoresis showed that high molecular weight (HMW) HA (an average of approximately 3000 kDa) was predominantly extracted in isotonic Extract A (70.1 +/- 6.0%) and PBS (37.7 +/- 3.2%). Western blot analysis of these extracts with hyaluronidase digestion or NaOH treatment revealed that HMW HA was covalently linked with the heavy chains (HCs) of inter-alpha-inhibitor (IalphaI) via a NaOH-sensitive bond, likely transferred by the tumor necrosis factor-alpha stimulated gene-6 protein (TSG-6). This HC.HA complex (nHC*HA) could be purified from Extract PBS by two rounds of CsCl/guanidine HCl ultracentrifugation as well as in vitro reconstituted (rcHC*HA) by mixing HMW HA, serum IalphaI, and recombinant TSG-6. Consistent with previous reports, Extract PBS suppressed transforming growth factor-beta1 promoter activation in corneal fibroblasts and induced mac ro phage apoptosis. However, these effects were abolished by hyaluronidase digestion or heat treatment. More importantly, the effects were retained in the nHC*HA or rcHC*HA. These data collectively suggest that the HC*HA complex is the active component in AM responsible in part for clinically observed anti-inflammatory and anti-scarring actions.
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Affiliation(s)
- Hua He
- From TissueTech, Inc. and Ocular Surface Center
| | - Wei Li
- From TissueTech, Inc. and Ocular Surface Center
| | - David Y. Tseng
- Ocular Surface Research Education Foundation, Miami, Florida 33173 and
| | - Shan Zhang
- From TissueTech, Inc. and Ocular Surface Center
| | - Szu-Yu Chen
- From TissueTech, Inc. and Ocular Surface Center
| | - Anthony J. Day
- the Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, United Kingdom
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Gabison EE, Huet E, Baudouin C, Menashi S. Direct epithelial–stromal interaction in corneal wound healing: Role of EMMPRIN/CD147 in MMPs induction and beyond. Prog Retin Eye Res 2009; 28:19-33. [DOI: 10.1016/j.preteyeres.2008.11.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Li W, He H, Chen YT, Hayashida Y, Tseng SCG. Reversal of myofibroblasts by amniotic membrane stromal extract. J Cell Physiol 2008; 215:657-64. [PMID: 18181149 DOI: 10.1002/jcp.21345] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Myofibroblasts play an important role in morphogenesis, inflammation, and fibrosis in most tissues. The amniotic membrane stroma can maintain keratocytes in cultures and prevent them from differentiating into myofibroblasts. However, it is unknown whether the AM stroma can also reverse differentiated myofibroblasts. In this study, we found that amniotic membrane stromal cells (AMSCs), which adopted fibroblastic phenotype in vivo, quickly and completely differentiated into myofibroblasts during ex vivo culture in DMEM/FBS on plastic within 2 passages. When cultured on type I collagen, the myofibroblasts maintained their phenotype, however, when these myofibroblasts were re-seeded onto a cryopreserved amniotic membrane stromal surface, they reversed to the fibroblast phenotype. Moreover, we found that the amniotic membrane stromal extract not only helps maintain primary AMSCs fibroblastic phenotype in vitro, but also can reverse differentiated myofibroblasts back to fibroblasts. This reversal was not coupled with cell proliferation. We concluded that the amniotic membrane stroma contains soluble factors that can regulate the mesenchymal cell differentiation. Further investigation into the identity of these factors and the control mechanisms may unravel a new scar-reversing strategy.
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Affiliation(s)
- Wei Li
- TissueTech, Inc., Miami, Florida, USA
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Kawakita T, Espana EM, He H, Smiddy R, Parel JM, Liu CY, Tseng SCG. Preservation and expansion of the primate keratocyte phenotype by downregulating TGF-beta signaling in a low-calcium, serum-free medium. Invest Ophthalmol Vis Sci 2006; 47:1918-27. [PMID: 16638999 PMCID: PMC1569676 DOI: 10.1167/iovs.05-1040] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
PURPOSE To demonstrate whether the original keratocyte phenotype is maintained with proliferative activity by suppressing TGF-beta signaling in rhesus monkey keratocytes expanded in a serum-free and low-[Ca2+] medium. METHODS Rhesus monkey keratocytes were isolated from central corneal buttons by collagenase digestion for 16 hours, seeded on plastic in Dulbecco's modified Eagle's medium (DMEM) containing insulin-transferrin-sodium selenite (ITS) supplement (DMEM/ITS) or 10% fetal bovine serum (DMEM/10% FBS), or in a defined keratinocyte serum-free medium (KSFM). After confluence, cells in KSFM were continuously subcultured at a 1-to-3 split. Cellular proliferation was analyzed by immunostaining for Ki67 and the MTT assay. The cellular phenotype was determined by immunostaining for aldehyde dehydrogenase (ALDH), keratocan, and CD34 and by the expression of keratocan promoter-driven enhanced cyan fluorescent protein (ECFP). The stability of the keratocyte phenotype was examined by switching KSFM to DMEM/ITS and DMEM/10% FBS. TGF-beta signaling was monitored by measuring the promoter activity of TGF-beta1, -beta2, and -beta RII after transient adenoviral transfection, and cytolocalization of Smad2 and Smad4. RESULTS In KSFM, monkey keratocytes proliferated while maintaining the expression of keratocan, CD34, and ALDH proteins and keratocan promoter-driven ECFP for at least 15 passages. The nuclear accumulation of Smad2 and Smad4 and the promoter activities of TGF-beta1 and -beta RII were significantly downregulated in KSFM compared with DMEM/10% FBS. In KSFM, an increase of [Ca2+] to 1.8 mM and addition of 10% FBS synergistically downregulated the keratocan promoter activity, facilitated Smad2 and Smad4 nuclear translocation, and upregulated TGF-beta1 and -beta RII promoter activities. CONCLUSIONS The normal monkey keratocyte phenotype can be maintained in a low-calcium, serum-free medium by downregulating Smad-mediated TGF-beta signaling.
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Affiliation(s)
- Tetsuya Kawakita
- From TissueTech, Inc., Ocular Surface Center, Miami, Florida; and the
| | - Edgar M. Espana
- From TissueTech, Inc., Ocular Surface Center, Miami, Florida; and the
| | - Hua He
- From TissueTech, Inc., Ocular Surface Center, Miami, Florida; and the
| | - Robert Smiddy
- From TissueTech, Inc., Ocular Surface Center, Miami, Florida; and the
| | - Jean-Marie Parel
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami School of Medicine, Miami, Florida
| | - Chia-Yang Liu
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami School of Medicine, Miami, Florida
| | - Scheffer C. G. Tseng
- From TissueTech, Inc., Ocular Surface Center, Miami, Florida; and the
- Corresponding author: Scheffer C. G. Tseng, Ocular Surface Center, 7000 SW 97 Avenue, Suite 213, Miami, FL 33176;
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Abstract
According to the "classical" doctrine, resident cells of the cornea include the stratified epithelial cells, quiescent keratocytes, and a single layer of nondividing endothelial cells. However, it has become increasingly evident that other cell types are involved in the homeostasis of the cornea. The presence of various cell types from different lineages has raised concern among researchers as to what we are actually "seeing" in the cornea. Although definitive conclusions cannot yet be drawn, this review attempts to clarify the various accessory cell types reported in the human and murine cornea. The epithelial layer of the limbal area includes melanocytes, as well as antigen-presenting cells that are also present in the peripheral clear cornea. The most debated tissue currently is perhaps the corneal stroma, where resident keratocytes are not as large a population as was previously believed. Bone marrow-derived cells are found in the cornea, and these may not express the typical HLA molecules usually found on the surface of antigen-presenting cells. Nerve fibers extend though the superficial stroma to form a plexus beneath the epithelium. Although the cell body of the neuron itself is not in the cornea, neural glial cells, such as Schwann cells, are present in the stroma. The use of specific molecular markers and high-quality imaging techniques will be required to fully elucidate the various accessory cells of the cornea and their function.
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Affiliation(s)
- Shigeto Shimmura
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.
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