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Lucius A, Chhatwal S, Valtink M, Reinach PS, Li A, Pleyer U, Mergler S. L-Carnitine Suppresses Transient Receptor Potential Vanilloid Type 1 Activation in Human Corneal Epithelial Cells. Int J Mol Sci 2023; 24:11815. [PMID: 37511574 PMCID: PMC10380586 DOI: 10.3390/ijms241411815] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/17/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
Tear film hyperosmolarity induces dry eye syndrome (DES) through transient receptor potential vanilloid type 1 (TRPV1) activation. L-carnitine is a viable therapeutic agent since it protects against this hypertonicity-induced response. Here, we investigated whether L-carnitine inhibits TRPV1 activation by blocking heat- or capsaicin-induced increases in Ca2+ influx or hyperosmotic stress-induced cell volume shrinkage in a human corneal epithelial cell line (HCE-T). Single-cell fluorescence imaging of calcein/AM-loaded cells or fura-2/AM-labeled cells was used to evaluate cell volume changes and intracellular calcium levels, respectively. Planar patch-clamp technique was used to measure whole-cell currents. TRPV1 activation via either capsaicin (20 µmol/L), hyperosmolarity (≈450 mosmol/L) or an increase in ambient bath temperature to 43 °C induced intracellular calcium transients and augmented whole-cell currents, whereas hypertonicity induced cell volume shrinkage. In contrast, either capsazepine (10 µmol/L) or L-carnitine (1-3 mmol/L) reduced all these responses. Taken together, L-carnitine and capsazepine suppress hypertonicity-induced TRPV1 activation by blocking cell volume shrinkage.
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Affiliation(s)
- Alexander Lucius
- Klinik für Augenheilkunde, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
| | - Sirjan Chhatwal
- Klinik für Augenheilkunde, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
| | - Monika Valtink
- Faculty of Medicine, Institute of Anatomy, TU Dresden, 01216 Dresden, Germany
- Equality and Diversity Unit, Faculty of Medicine, TU Dresden, 01307 Dresden, Germany
| | - Peter S Reinach
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou 325027, China
| | - Aruna Li
- Klinik für Augenheilkunde, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
| | - Uwe Pleyer
- Klinik für Augenheilkunde, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
| | - Stefan Mergler
- Klinik für Augenheilkunde, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
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2
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Morawietz H, Frenzel A, Mieting A, Goettsch W, Valtink M, Roehlecke C, Jászai J, Funk RHW, Becker KA, Engelmann K. Induction of vascular endothelial growth factor-A 165a in human retinal and endothelial cells in response to glyoxal. Ther Apher Dial 2022; 26 Suppl 1:29-34. [PMID: 36468302 DOI: 10.1111/1744-9987.13803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 12/10/2021] [Accepted: 01/13/2022] [Indexed: 12/09/2022]
Abstract
Low-density lipoprotein (LDL) apheresis is effective and safe for patients with diabetes, proteinuria, and dyslipidemia. Diabetes mellitus is accompanied by ocular microvascular complications like retinal neovascularization or diabetic macular edema. These are leading causes of blindness and can be mediated by abnormal vessel growth and increased vascular permeability due to elevated levels of vascular endothelial growth factor (VEGF) in diabetic patients. In this study, we established methods to study the expression of different VEGF isoforms in human retinal and endothelial cells. The VEGF-A165a isoform is much higher expressed in retinal cells, compared to endothelial cells. Stimulation with glyoxal as a model of oxidative stress under diabetic conditions lead to a pronounced induction of VEGF-A165a in human retinal and endothelial cells. These data suggest that diabetes and oxidative stress induce VEGF-A isoforms which could be relevant in regulating the ingrowths of novel blood vessels into the retina in diabetic patients.
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Affiliation(s)
- Henning Morawietz
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital and Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Annika Frenzel
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital and Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Alice Mieting
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital and Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Winfried Goettsch
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital and Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Monika Valtink
- Institute of Anatomy and Equality and Diversity Unit, Faculty of Medicine Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Cora Roehlecke
- Institute of Anatomy and Equality and Diversity Unit, Faculty of Medicine Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - József Jászai
- Institute of Anatomy and Equality and Diversity Unit, Faculty of Medicine Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Richard H W Funk
- Institute of Anatomy and Equality and Diversity Unit, Faculty of Medicine Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Klio A Becker
- Department of Ophthalmology, Klinikum Chemnitz gGmbH, Chemnitz, Germany
| | - Katrin Engelmann
- Department of Ophthalmology, Klinikum Chemnitz gGmbH, Chemnitz, Germany
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Donau J, Luo H, Virta I, Skupin A, Pushina M, Loeffler J, Haertel FV, Das A, Kurth T, Gerlach M, Lindemann D, Reinach PS, Mergler S, Valtink M. TRPV4 Stimulation Level Regulates Ca2+-Dependent Control of Human Corneal Endothelial Cell Viability and Survival. Membranes 2022; 12:membranes12030281. [PMID: 35323756 PMCID: PMC8952823 DOI: 10.3390/membranes12030281] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 02/18/2022] [Accepted: 02/24/2022] [Indexed: 02/04/2023]
Abstract
The functional contribution of transient receptor potential vanilloid 4 (TRPV4) expression in maintaining human corneal endothelial cells (HCEC) homeostasis is unclear. Accordingly, we determined the effects of TRPV4 gene and protein overexpression on responses modulating the viability and survival of HCEC. Q-PCR, Western blot, FACS analyses and fluorescence single-cell calcium imaging confirmed TRPV4 gene and protein overexpression in lentivirally transduced 12V4 cells derived from their parent HCEC-12 line. Although TRPV4 overexpression did not alter the baseline transendothelial electrical resistance (TEER), its cellular capacitance (Ccl) was larger than that in its parent. Scanning electron microscopy revealed that only the 12V4 cells developed densely packed villus-like protrusions. Stimulation of TRPV4 activity with GSK1016790A (GSK101, 10 µmol/L) induced larger Ca2+ transients in the 12V4 cells than those in the parental HCEC-12. One to ten nmol/L GSK101 decreased 12V4 viability, increased cell death rates and reduced the TEER, whereas 1 µmol/L GSK101 was required to induce similar effects in the HCEC-12. However, the TRPV4 channel blocker RN1734 (1 to 30 µmol/L) failed to alter HCEC-12 and 12V4 morphology, cell viability and metabolic activity. Taken together, TRPV4 overexpression altered both the HCEC morphology and markedly lowered the GSK101 dosages required to stimulate its channel activity.
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Affiliation(s)
- Jennifer Donau
- Institute of Anatomy, Faculty of Medicine, TU Dresden, 01307 Dresden, Germany; (J.D.); (A.S.); (M.P.); (J.L.)
- Institute of Medical Microbiology and Virology, Faculty of Medicine, TU Dresden, 01307 Dresden, Germany;
| | - Huan Luo
- Klinik für Augenheilkunde, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 13353 Berlin, Germany; (H.L.); (I.V.)
| | - Iiris Virta
- Klinik für Augenheilkunde, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 13353 Berlin, Germany; (H.L.); (I.V.)
| | - Annett Skupin
- Institute of Anatomy, Faculty of Medicine, TU Dresden, 01307 Dresden, Germany; (J.D.); (A.S.); (M.P.); (J.L.)
- Institute of Medical Microbiology and Virology, Faculty of Medicine, TU Dresden, 01307 Dresden, Germany;
| | - Margarita Pushina
- Institute of Anatomy, Faculty of Medicine, TU Dresden, 01307 Dresden, Germany; (J.D.); (A.S.); (M.P.); (J.L.)
| | - Jana Loeffler
- Institute of Anatomy, Faculty of Medicine, TU Dresden, 01307 Dresden, Germany; (J.D.); (A.S.); (M.P.); (J.L.)
| | - Frauke V. Haertel
- Institute of Physiology, Faculty of Medicine, University Giessen, 35392 Giessen, Germany;
- Institute of Physiology, Faculty of Medicine, TU Dresden, 01307 Dresden, Germany;
| | - Anupam Das
- Institute of Physiology, Faculty of Medicine, TU Dresden, 01307 Dresden, Germany;
| | - Thomas Kurth
- Center for Molecular and Cellular Bioengineering (CMCB), Technology Platform, TU Dresden, 01307 Dresden, Germany;
| | - Michael Gerlach
- Core Facility Cellular Imaging, Faculty of Medicine, TU Dresden, 01307 Dresden, Germany;
| | - Dirk Lindemann
- Institute of Medical Microbiology and Virology, Faculty of Medicine, TU Dresden, 01307 Dresden, Germany;
| | - Peter S. Reinach
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou 325027, China;
| | - Stefan Mergler
- Klinik für Augenheilkunde, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 13353 Berlin, Germany; (H.L.); (I.V.)
- Correspondence: (S.M.); (M.V.)
| | - Monika Valtink
- Institute of Anatomy, Faculty of Medicine, TU Dresden, 01307 Dresden, Germany; (J.D.); (A.S.); (M.P.); (J.L.)
- Equality and Diversity Unit, Faculty of Medicine, TU Dresden, 01307 Dresden, Germany
- Correspondence: (S.M.); (M.V.)
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4
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Turan E, Valtink M, Reinach PS, Skupin A, Luo H, Brockmann T, Ba Salem MHO, Pleyer U, Mergler S. L-carnitine suppresses transient receptor potential vanilloid type 1 activity and myofibroblast transdifferentiation in human corneal keratocytes. J Transl Med 2021; 101:680-689. [PMID: 33637945 PMCID: PMC8137454 DOI: 10.1038/s41374-021-00538-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 01/04/2021] [Accepted: 01/04/2021] [Indexed: 11/14/2022] Open
Abstract
Corneal stromal wound healing is a well-balanced process promoted by overlapping phases including keratocyte proliferation, inflammatory-related events, and tissue remodeling. L-carnitine as a natural antioxidant has shown potential to reduce stromal fibrosis, yet the underlying pathway is still unknown. Since transient receptor potential vanilloid 1 (TRPV1) is a potential drug target for improving the outcome of inflammatory/fibrogenic wound healing, we investigated if L-carnitine can mediate inhibition of the fibrotic response through suppression of TRPV1 activation in human corneal keratocytes (HCK). We determined TRPV1-induced intracellular calcium transients using fluorescence calcium imaging, channel currents by planar patch-clamping, and cell migration by scratch assay for wound healing. The potential L-carnitine effect on TRPV1-induced myofibroblast transdifferentiation was evaluated by immunocytochemical detection of alpha smooth muscle actin. RT-PCR analysis confirmed TRPV1 mRNA expression in HCK. L-carnitine (1 mmol/l) inhibited either capsaicin (CAP) (10 µmol/l), hypertonic stress (450 mOsmol/l), or thermal increase (>43 °C) induced Ca2+ transients and corresponding increases in TRPV1-induced inward and outward whole-cell currents. This was accompanied by suppression of injury-induced increases in myofibroblast transdifferentiation and cell migration. In conclusion, L-carnitine contributes to inhibit stromal scarring through suppressing an injury-induced intrinsic TRPV1 activity that is linked with induction of myofibroblast transdifferentiation in HCK cells.
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Affiliation(s)
- Elizabeth Turan
- Klinik für Augenheilkunde, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Monika Valtink
- Institute of Anatomy, Faculty of Medicine Carl Gustav Carus of the TU Dresden, Dresden, Germany
| | - Peter S Reinach
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, PR China
| | - Annett Skupin
- Institute of Anatomy, Faculty of Medicine Carl Gustav Carus of the TU Dresden, Dresden, Germany
| | - Huan Luo
- Klinik für Augenheilkunde, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Tobias Brockmann
- Klinik für Augenheilkunde, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
- Berlin Institute of Health (BIH), Kapelle-Ufer 2, 10117, Berlin, Germany
- Department of Ophthalmology, Universitätsmedizin Rostock, Rostock, Germany
| | - Marah Hussain Omar Ba Salem
- Klinik für Augenheilkunde, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Uwe Pleyer
- Klinik für Augenheilkunde, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Stefan Mergler
- Klinik für Augenheilkunde, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany.
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5
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Petsoglou C, Wen L, Hoque M, Zhu M, Valtink M, Sutton G, You J. Effects of human platelet lysate on the growth of cultured human corneal endothelial cells. Exp Eye Res 2021; 208:108613. [PMID: 33984343 DOI: 10.1016/j.exer.2021.108613] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 04/22/2021] [Accepted: 04/29/2021] [Indexed: 01/14/2023]
Abstract
Human platelet lysate (hPL) as a replacement for foetal bovine serum (FBS) in culturing human corneal endothelium is an emerging area of interest, although there are limited studies evaluating the quality of the hPL being used. Our study aimed to evaluate variations between sources of hPL and to explore the efficacy of hPL (with and without heparin) as a replacement for FBS in culturing human corneal endothelial cells in vitro. Immortalized human corneal endothelial cells (B4G12) and primary human corneal endothelial cells (PHCEnCs, n = 11 donors, age from 36 to 85 years old) were cultured with 5% hPL or FBS. A full characterisation of the effects of hPL and FBS on cell growth was conducted using IncuCyte Zoom (percentage cell confluence and population doubling time, PDT) to analyse cell proliferation. AlamarBlue assays were used to measure cell viability. The concentration of fibrinogen, PDGF, hEGF, VEGF and bFGF in two sources of hPL were analyzed by Enzyme-linked immunosorbent assay. Expression and localization of Na+/K+-ATPase, ZO-1 and CD166 on PHCEnCs and B4G12 cells were assessed with immunofluorescence and immunoblotting. Our results showed that a significant difference in fibrinogen, hEGF and VEGF concentrations was found between two sources of hPL. Heparin impaired the positive effect of hPL on cell growth. PDT and alamarBlue showed that hPL significantly increased proliferation and viability of PHCEnCs in two of three donors, and immunostaining indicated that hPL increased ZO-1 and CD166 expression but not Na+/K+-ATPase on PHCEnCs. In addition, heterogeneities on immunopositivity of Na+/K+-ATPase and ZO-1 and morphology were found on PHCEnCs derived from an individual donor cultured with hPL medium. In conclusion, hPL showed positive effect on primary corneal endothelial cell growth, and maintenance of their cellular characteristics compared to FBS. hPL can be considered as a supplement to replace FBS in PHCEnC culture. However, the variation observed between different hPL sources suggests that a standard quality control monitoring system such as storage time and a minimal concentration of growth factors may need to be established.
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Affiliation(s)
- Constantinos Petsoglou
- Discipline of Ophthalmology, Sydney Medical School, The University of Sydney, Camperdown, NSW, 2006, Australia; New South Wales Tissue Bank, New South Wales Organ and Tissue Donation Service, Sydney, NSW, 2000, Australia; Save Sight Institute, The University of Sydney, Sydney, NSW, 2000, Australia; Corneal Unit, Sydney Eye Hospital, Sydney, NSW, 2000, Australia
| | - Li Wen
- New South Wales Tissue Bank, New South Wales Organ and Tissue Donation Service, Sydney, NSW, 2000, Australia
| | - Monira Hoque
- New South Wales Tissue Bank, New South Wales Organ and Tissue Donation Service, Sydney, NSW, 2000, Australia
| | - Meidong Zhu
- New South Wales Tissue Bank, New South Wales Organ and Tissue Donation Service, Sydney, NSW, 2000, Australia; Save Sight Institute, The University of Sydney, Sydney, NSW, 2000, Australia.
| | - Monika Valtink
- Institute of Anatomy, Faculty of Medicine, TU Dresden, Fetscherstr. 74, 01307, Dresden, Germany
| | - Gerard Sutton
- Discipline of Ophthalmology, Sydney Medical School, The University of Sydney, Camperdown, NSW, 2006, Australia; New South Wales Tissue Bank, New South Wales Organ and Tissue Donation Service, Sydney, NSW, 2000, Australia; Save Sight Institute, The University of Sydney, Sydney, NSW, 2000, Australia; Corneal Unit, Sydney Eye Hospital, Sydney, NSW, 2000, Australia
| | - Jingjing You
- Save Sight Institute, The University of Sydney, Sydney, NSW, 2000, Australia
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6
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Engelmann K, Sievert U, Hölig K, Wittig D, Weßlau S, Domann S, Siegert G, Valtink M. [Effect of autologous platelet concentrates on the anatomical and functional outcome of late stage macular hole surgery: A retrospective analysis]. Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2016; 58:1289-98. [PMID: 26431723 DOI: 10.1007/s00103-015-2251-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND The macular hole (MH) is a disorder of the visual center of the retina in humans. An untreated MH leads to loss of central visual acuity and reading ability. Surgery for early-stage macular holes has been very successful for many years and leads to very good anatomical and functional results. Despite continuous improvement of surgical procedures, the outcome for the later stages of MH is still unsatisfactory. METHOD In a retrospective analysis, we investigated the effect of autologous platelet concentrates in patients presenting later stages of MHs (stage III-IV) with respect to anatomic success (hole closure) and recovery of vision. The application of platelets was performed during retinal surgery (pars plana vitrectomy, ppV). In addition, selected platelet concentrates were qualitatively analysed for growth factors and platelet adhesion. RESULTS In the first group, 74% of the patients showed a good anatomical macular hole closure. The analyses of the platelet concentrates indicated a possible wound-healing effect due to growth factors (e.g. the platelet-derived growth factor, PDGF) and lesser to the ability of the platelets to adhere after ristocetin administration. Further optimization of the production process of platelet concentrates and of the surgical procedure in the second group of patients showed an increase of the anatomical success (92%) and a very rapid increase of visual acuity within six weeks. DISCUSSION In the past, the primary goal of MH surgery was to optimize the surgical procedures. Only few concepts focused on wound healing. Based on our data, we postulate the use of autologous platelet concentrates in MH surgery as a healing concept, which helps to increase the functional success of late-stage macular hole surgery.
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Affiliation(s)
- Katrin Engelmann
- Klinik für Augenheilkunde, Klinikum Chemnitz gGmbH, Flemmingstraße 2, 09116, Chemnitz, Deutschland. .,Institut für Anatomie, Medizinische Fakultät Carl Gustav Carus der TU Dresden, Fetscherstraße 74, Dresden, 01307, Deutschland.
| | - Uwe Sievert
- DRK-Blutspendendienst Nord-Ost gGmbH, Chemnitz, Deutschland
| | - Kristina Hölig
- Bereich Transfusionsmedizin an der Medizinischen Klinik I, Universitätsklinikum Carl Gustav Carus Dresden, Fetscherstr. 74, 01307, Dresden, Deutschland
| | - Dierk Wittig
- Klinik für Augenheilkunde, Klinikum Chemnitz gGmbH, Flemmingstraße 2, 09116, Chemnitz, Deutschland
| | - Sarah Weßlau
- Klinik für Augenheilkunde, Klinikum Chemnitz gGmbH, Flemmingstraße 2, 09116, Chemnitz, Deutschland
| | - Stefan Domann
- Institut für Anatomie, Medizinische Fakultät Carl Gustav Carus der TU Dresden, Fetscherstraße 74, Dresden, 01307, Deutschland
| | - Gabriele Siegert
- Institut für Klinische Chemie und Laboratoriumsmedizin, Universitätsklinikum Carl Gustav Carus Dresden, 01307, Dresden, Fetscherstr. 74, Deutschland
| | - Monika Valtink
- Institut für Anatomie, Medizinische Fakultät Carl Gustav Carus der TU Dresden, Fetscherstraße 74, Dresden, 01307, Deutschland
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7
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Knels L, Valtink M, Piazena H, de la Vega Marin J, Gommel K, Lupp A, Roehlecke C, Mehner M, Funk RHW. Effects of Narrow-band IR-A and of Water-Filtered Infrared A on Fibroblasts. Photochem Photobiol 2016; 92:475-87. [DOI: 10.1111/php.12579] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2015] [Accepted: 01/20/2016] [Indexed: 12/17/2022]
Affiliation(s)
- Lilla Knels
- Institute of Anatomy, Faculty of Medicine; TU Dresden; Dresden Germany
| | - Monika Valtink
- Institute of Anatomy, Faculty of Medicine; TU Dresden; Dresden Germany
| | - Helmut Piazena
- Charité - University Medicine Berlin; Medical Photobiology Group; Berlin Germany
| | | | - Kerstin Gommel
- Institute of Anatomy, Faculty of Medicine; TU Dresden; Dresden Germany
| | - Amelie Lupp
- Institute of Pharmacology and Toxicology; Jena University Hospital; Jena Germany
| | - Cora Roehlecke
- Institute of Anatomy, Faculty of Medicine; TU Dresden; Dresden Germany
| | - Mirko Mehner
- Department of Anaesthesiology and Intensive Care Medicine; Clinical Sensoring and Monitoring; Faculty of Medicine Carl Gustav Carus; TU Dresden; Dresden Germany
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8
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Valtink M, Donath P, Engelmann K, Knels L. Erratum to: Effect of different culture media and deswelling agents on survival of human corneal endothelial and epithelial cells in vitro. Graefes Arch Clin Exp Ophthalmol 2016; 254:1029. [PMID: 26876239 DOI: 10.1007/s00417-016-3306-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Affiliation(s)
- Monika Valtink
- Institute of Anatomy, Faculty of Medicine Carl Gustav Carus of the TU Dresden, Fetscherstr. 74, 01307, Dresden, Germany.
| | - Patricia Donath
- Institute of Anatomy, Faculty of Medicine Carl Gustav Carus of the TU Dresden, Fetscherstr. 74, 01307, Dresden, Germany
| | - Katrin Engelmann
- Department of Ophthalmology, Klinikum Chemnitz gGmbH, Flemmingstr. 2, 09116, Chemnitz, Germany
| | - Lilla Knels
- Institute of Anatomy, Faculty of Medicine Carl Gustav Carus of the TU Dresden, Fetscherstr. 74, 01307, Dresden, Germany
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9
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Valtink M, Donath P, Engelmann K, Knels L. Effect of different culture media and deswelling agents on survival of human corneal endothelial and epithelial cells in vitro. Graefes Arch Clin Exp Ophthalmol 2015; 254:285-95. [DOI: 10.1007/s00417-015-3235-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 11/18/2015] [Accepted: 11/30/2015] [Indexed: 12/18/2022] Open
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10
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Teichmann J, Nitschke M, Pette D, Valtink M, Gramm S, Härtel FV, Noll T, Funk RHW, Engelmann K, Werner C. Thermo-responsive cell culture carriers based on poly(vinyl methyl ether)-the effect of biomolecular ligands to balance cell adhesion and stimulated detachment. Sci Technol Adv Mater 2015; 16:045003. [PMID: 27877823 PMCID: PMC5090182 DOI: 10.1088/1468-6996/16/4/045003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 06/19/2015] [Accepted: 06/22/2015] [Indexed: 06/06/2023]
Abstract
Two established material systems for thermally stimulated detachment of adherent cells were combined in a cross-linked polymer blend to merge favorable properties. Through this approach poly(N-isopropylacrylamide) (PNiPAAm) with its superior switching characteristic was paired with a poly(vinyl methyl ether)-based composition that allows adjusting physico-chemical and biomolecular properties in a wide range. Beyond pure PNiPAAm, the proposed thermo-responsive coating provides thickness, stiffness and swelling behavior, as well as an apposite density of reactive sites for biomolecular functionalization, as effective tuning parameters to meet specific requirements of a particular cell type regarding initial adhesion and ease of detachment. To illustrate the strength of this approach, the novel cell culture carrier was applied to generate transplantable sheets of human corneal endothelial cells (HCEC). Sheets were grown, detached, and transferred onto planar targets. Cell morphology, viability and functionality were analyzed by immunocytochemistry and determination of transepithelial electrical resistance (TEER) before and after sheet detachment and transfer. HCEC layers showed regular morphology with appropriate TEER. Cells were positive for function-associated marker proteins ZO-1, Na+/K+-ATPase, and paxillin, and extracellular matrix proteins fibronectin, laminin and collagen type IV before and after transfer. Sheet detachment and transfer did not impair cell viability. Subsequently, a potential application in ophthalmology was demonstrated by transplantation onto de-endothelialized porcine corneas in vitro. The novel thermo-responsive cell culture carrier facilitates the generation and transfer of functional HCEC sheets. This paves the way to generate tissue engineered human corneal endothelium as an alternative transplant source for endothelial keratoplasty.
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Affiliation(s)
- Juliane Teichmann
- Institute of Anatomy, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, D-01307 Dresden, Germany
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Hohe Straße 6, D-01069 Dresden, Germany
| | - Mirko Nitschke
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Hohe Straße 6, D-01069 Dresden, Germany
| | - Dagmar Pette
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Hohe Straße 6, D-01069 Dresden, Germany
| | - Monika Valtink
- Institute of Anatomy, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, D-01307 Dresden, Germany
| | - Stefan Gramm
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Hohe Straße 6, D-01069 Dresden, Germany
- Herlac Coswig GmbH, Industriestraße 28, D-01640 Coswig, Germany
| | - Frauke V Härtel
- Institute of Physiology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, D-01307 Dresden, Germany
| | - Thomas Noll
- Institute of Physiology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, D-01307 Dresden, Germany
| | - Richard H W Funk
- Institute of Anatomy, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, D-01307 Dresden, Germany
- CRTD/DFG-Center for Regenerative Therapies Dresden—Cluster of Excellence, Fetscherstraße 105, D-01307 Dresden, Germany
| | - Katrin Engelmann
- Institute of Anatomy, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, D-01307 Dresden, Germany
- CRTD/DFG-Center for Regenerative Therapies Dresden—Cluster of Excellence, Fetscherstraße 105, D-01307 Dresden, Germany
- Department of Ophthalmology, Klinikum Chemnitz gGmbH, Flemmingstraße 2, D-09116 Chemnitz, Germany
| | - Carsten Werner
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Hohe Straße 6, D-01069 Dresden, Germany
- CRTD/DFG-Center for Regenerative Therapies Dresden—Cluster of Excellence, Fetscherstraße 105, D-01307 Dresden, Germany
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Kotomin I, Valtink M, Hofmann K, Frenzel A, Morawietz H, Werner C, Funk RHW, Engelmann K. Sutureless fixation of amniotic membrane for therapy of ocular surface disorders. PLoS One 2015; 10:e0125035. [PMID: 25955359 PMCID: PMC4425509 DOI: 10.1371/journal.pone.0125035] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 01/17/2015] [Indexed: 11/18/2022] Open
Abstract
Amniotic membrane is applied to the diseased ocular surface to stimulate wound healing and tissue repair, because it releases supportive growth factors and cytokines. These effects fade within about a week after application, necessitating repeated application. Generally, amniotic membrane is fixed with sutures to the ocular surface, but surgical intervention at the inflamed or diseased site can be detrimental. Therefore, we have developed a system for the mounting of amniotic membrane between two rings for application to a diseased ocular surface without surgical intervention (sutureless amniotic membrane transplantation). With this system, AmnioClip, amniotic membrane can be applied like a large contact lens. First prototypes were tested in an experiment on oneself for wearing comfort. The final system was tested on 7 patients in a pilot study. A possible influence of the ring system on the biological effects of amniotic membrane was analyzed by histochemistry and by analyzing the expression of vascular endothelial growth factor-A (VEGF-A), hepatocyte growth factor (HGF), fibroblast growth factor 2 (FGF 2) and pigment epithelium-derived factor (PEDF) from amniotic membranes before and after therapeutic application. The final product, AmnioClip, showed good tolerance and did not impair the biological effects of amniotic membrane. VEGF-A and PEDF mRNA was expressed in amniotic membrane after storage and mounting before transplantation, but was undetectable after a 7-day application period. Consequently, transplantation of amniotic membranes with AmnioClip provides a sutureless and hence improved therapeutic strategy for corneal surface disorders.
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Affiliation(s)
- Ilya Kotomin
- Department of Ophthalmology, Klinikum Chemnitz gGmbH, Chemnitz, Germany
| | - Monika Valtink
- Institute of Anatomy, Medical Faculty Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Kai Hofmann
- Deutsche Gesellschaft für Gewebetransplantation, DGFG, Hannover, Germany
| | - Annika Frenzel
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, TU Dresden, Dresden, Germany
| | - Henning Morawietz
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, TU Dresden, Dresden, Germany
- CRTD / DFG-Center for Regenerative Therapies Dresden—Cluster of Excellence, Dresden, Germany
| | - Carsten Werner
- CRTD / DFG-Center for Regenerative Therapies Dresden—Cluster of Excellence, Dresden, Germany
- Leibniz-Institut für Polymerforschung Dresden e.V., Dresden, Germany
| | - Richard H. W. Funk
- Institute of Anatomy, Medical Faculty Carl Gustav Carus, TU Dresden, Dresden, Germany
- CRTD / DFG-Center for Regenerative Therapies Dresden—Cluster of Excellence, Dresden, Germany
| | - Katrin Engelmann
- Department of Ophthalmology, Klinikum Chemnitz gGmbH, Chemnitz, Germany
- Deutsche Gesellschaft für Gewebetransplantation, DGFG, Hannover, Germany
- CRTD / DFG-Center for Regenerative Therapies Dresden—Cluster of Excellence, Dresden, Germany
- * E-mail:
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Mergler S, Valtink M, Takayoshi S, Okada Y, Miyajima M, Saika S, Reinach PS. Temperature-sensitive transient receptor potential channels in corneal tissue layers and cells. Ophthalmic Res 2014; 52:151-9. [PMID: 25301091 DOI: 10.1159/000365334] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 06/16/2014] [Indexed: 11/19/2022]
Abstract
We here provide a brief summary of the characteristics of transient receptor potential channels (TRPs) identified in corneal tissue layers and cells. In general, TRPs are nonselective cation channels which are Ca(2+) permeable. Most TRPs serve as thermosensitive molecular sensors (thermo-TRPs). Based on their functional importance, the possibilities are described for drug-targeting TRP activity in a clinical setting. TRPs are expressed in various tissues of the eye including both human corneal epithelial and endothelial layers as well as stromal fibroblasts and stromal nerve fibers. TRP vanilloid type 1 (TRPV1) heat receptor, also known as capsaicin receptor, along with TRP melastatin type 8 (TRPM8) cold receptor, which is also known as menthol receptor, are prototypes of the thermo-TRP family. The TRPV1 functional channel is the most investigated TRP channel in these tissues, owing to its contribution to maintaining tissue homeostasis as well as eliciting wound healing responses to injury. Other thermo-TRP family members identified in these tissues are TRPV2, 3 and 4. Finally, there is the TRP ankyrin type 1 (TRPA1) cold receptor. All of these thermo-TRPs can be activated within specific temperature ranges and transduce such inputs into chemical and electrical signals. Although several recent studies have begun to unravel complex roles for thermo-TRPs such as TRPV1 in corneal layers and resident cells, additional studies are needed to further elucidate their roles in health and disease.
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Affiliation(s)
- Stefan Mergler
- Department of Ophthalmology, Charité - Universitätsmedizin Berlin, Berlin, Germany
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Knels L, Goetze D, Engelmann K, Valtink M. Serum-free medium and hydroxyethyl starch supports cell survival better than Minimal Essential Medium and dextran in organ-cultured mouse corneas. Br J Ophthalmol 2014; 98:1744-50. [DOI: 10.1136/bjophthalmol-2014-305450] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Schönfelder J, Valtink M, Knels L, Funk RHW, Engelmann K, Wetzel C. Quality assessment of corneal storage media and their components. Graefes Arch Clin Exp Ophthalmol 2013; 252:77-82. [PMID: 24146268 DOI: 10.1007/s00417-013-2482-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 09/09/2013] [Accepted: 09/26/2013] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND To keep the loss of endothelial cell density in donor corneas to a minimum, a storage medium which is adjusted to their nutritional needs is necessary. Different media, used either serum-supplemented or serum-free, are available. The quality of medium- and serum-batches as well as support of endothelial cell viability by the medium are to be tested with a quality assured screening system that allows routine examination. METHODS A screening system was developed which is based on cell-culture tests with the well-established human corneal endothelial cell line HCEC-12, and therefore can be performed without the need for donor corneas. The cells are plated at a defined density in cell-culture dishes, and are cultured for a defined period of time in the test media. Evaluation is carried out by assaying cell count, activity of cell metabolism (resazurin conversion), and determining the number of apoptotic and necrotic cells (combined vital staining with YO-PRO®-1/propidium iodide and subsequent flow cytometry). RESULTS Human corneal endothelial cells that are cultured in a medium which is adjusted to their nutritional needs achieve higher cell numbers and show a higher metabolic rate. Simultaneously, the percentage of apoptotic and necrotic cells is lower. The screening system developed in this study allows for easy and reliable detection of slightest differences between different media, different processing steps for same media, and different supplements, as well as different serum batches. CONCLUSIONS The differentiated results show that the screening system is sensitive enough to show even minor quality differences. Therefore, it is more suitable than the hitherto commonly used growth assay with primary, mostly porcine, corneal endothelial cells.
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Affiliation(s)
- Jessy Schönfelder
- Coating of Flat Substrates, Medicine-Technical Application, Fraunhofer Institute for Electron Beam and Plasma Technology FEP, Winterbergstrasse 28, 01277, Dresden, Germany,
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Teichmann J, Valtink M, Nitschke M, Gramm S, Funk RHW, Engelmann K, Werner C. Tissue engineering of the corneal endothelium: a review of carrier materials. J Funct Biomater 2013; 4:178-208. [PMID: 24956190 PMCID: PMC4030930 DOI: 10.3390/jfb4040178] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Revised: 09/13/2013] [Accepted: 09/24/2013] [Indexed: 12/13/2022] Open
Abstract
Functional impairment of the human corneal endothelium can lead to corneal blindness. In order to meet the high demand for transplants with an appropriate human corneal endothelial cell density as a prerequisite for corneal function, several tissue engineering techniques have been developed to generate transplantable endothelial cell sheets. These approaches range from the use of natural membranes, biological polymers and biosynthetic material compositions, to completely synthetic materials as matrices for corneal endothelial cell sheet generation. This review gives an overview about currently used materials for the generation of transplantable corneal endothelial cell sheets with a special focus on thermo-responsive polymer coatings.
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Affiliation(s)
- Juliane Teichmann
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Institute of Biofunctional Polymer Materials, Hohe Straße 6, Dresden 01069, Germany.
| | - Monika Valtink
- Institute of Anatomy, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, Dresden 01307, Germany.
| | - Mirko Nitschke
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Institute of Biofunctional Polymer Materials, Hohe Straße 6, Dresden 01069, Germany.
| | - Stefan Gramm
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Institute of Biofunctional Polymer Materials, Hohe Straße 6, Dresden 01069, Germany.
| | - Richard H W Funk
- Institute of Anatomy, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, Dresden 01307, Germany.
| | - Katrin Engelmann
- CRTD/DFG-Center for Regenerative Therapies Dresden-Cluster of Excellence, Fetscherstraße 105, Dresden 01307, Germany.
| | - Carsten Werner
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Institute of Biofunctional Polymer Materials, Hohe Straße 6, Dresden 01069, Germany.
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Mergler S, Mertens C, Valtink M, Reinach PS, Székely VC, Slavi N, Garreis F, Abdelmessih S, Türker E, Fels G, Pleyer U. Functional significance of thermosensitive transient receptor potential melastatin channel 8 (TRPM8) expression in immortalized human corneal endothelial cells. Exp Eye Res 2013; 116:337-49. [PMID: 24135298 DOI: 10.1016/j.exer.2013.10.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2013] [Revised: 08/17/2013] [Accepted: 10/03/2013] [Indexed: 11/18/2022]
Abstract
Human corneal endothelial cells (HCEC) maintain appropriate tissue hydration and transparency by eliciting net ion transport coupled to fluid egress from the stroma into the anterior chamber. Such activity offsets tissue swelling caused by stromal imbibition of fluid. As corneal endothelial (HCE) transport function is modulated by temperature changes, we probed for thermosensitive transient receptor potential melastatin 8 (TRPM8) functional activity in immortalized human corneal endothelial cells (HCEC-12) and freshly isolated human corneal endothelial cells (HCEC) as a control. This channel is either activated upon lowering to 28 °C or by menthol, eucalyptol and icilin. RT-PCR and quantitative real-time PCR (qPCR) verified TRPM8 gene expression. Ca(2+) transients induced by either menthol (500 μmol/l), eucalyptol (3 mmol/l), or icilin (2-60 μmol/l) were identified using cell fluorescence imaging. The TRP channel blocker lanthanum III chloride (La(3+), 100 μmol/l) as well as the TRPM8 blockers BCTC (10 μmol/l) and capsazepine (CPZ, 10 μmol/l) suppressed icilin-induced Ca(2+) increases. In and outward currents induced by application of menthol (500 μmol/l) or icilin (50 μmol/l) were detected using the planar patch-clamp technique. A thermal transition from room temperature to ≈ 18 °C led to Ca(2+) increases that were inhibited by a TRPM8 blocker BCTC (10 μmol/l). Other thermosensitive TRP pathways whose heterogeneous Ca(2+) response patterns are suggestive of other Ca(2+) handling pathways were also detected upon strong cooling (≈10 °C). Taken together, functional TRPM8 expression in HCEC-12 and freshly dissociated HCEC suggests that HCE function can adapt to thermal variations through activation of this channel subtype.
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Affiliation(s)
- Stefan Mergler
- Charité - Universitätsmedizin Berlin, Campus Virchow-Clinic, Department of Ophthalmology, Augustenburger Platz 1, 13353 Berlin, Germany.
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Teichmann J, Valtink M, Gramm S, Nitschke M, Werner C, Funk R, Engelmann K. Human corneal endothelial cell sheets for transplantation: thermo-responsive cell culture carriers to meet cell-specific requirements. Acta Biomater 2013; 9:5031-9. [PMID: 23099299 DOI: 10.1016/j.actbio.2012.10.023] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 09/17/2012] [Accepted: 10/17/2012] [Indexed: 12/14/2022]
Abstract
Corneal endothelial diseases lead to severe vision impairment, motivating the transplantation of donor corneae or corneal endothelial lamellae, which is, however, impeded by endothelial cell loss during processing. Therefore, one prioritized aim in corneal tissue engineering is the generation of transplantable human corneal endothelial cell (HCEC) layers. Thermo-responsive cell culture carriers are widely used for non-enzymatic harvest of cell sheets. The current study presents a novel thermo-responsive carrier based on simultaneous electron beam immobilization and cross-linking of poly(vinyl methyl ether) (PVME) on polymeric surfaces, which allows one to adjust layer thickness, stiffness, switching amplitude and functionalization with bioactive molecules to meet cell type specific requirements. The efficacy of this approach for HCEC, which require elaborate cell culture conditions and are strongly adherent to the substratum, is demonstrated. The developed method may pave the way to tissue engineering of corneal endothelium and significantly improve therapeutic options.
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Figueiredo C, Vahlsing S, Valtink M, Börgel M, Engelmann K, Blasczyk R. Silencing HLA Class I Expression in Human Corneas to Decrease the Risk of Graft Rejection after Keratoplasty. Transplantation 2012. [DOI: 10.1097/00007890-201211271-01888] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Valtink M, Knels L, Stanke N, Engelmann K, Funk RHW, Lindemann D. Overexpression of human HMW FGF-2 but not LMW FGF-2 reduces the cytotoxic effect of lentiviral gene transfer in human corneal endothelial cells. Invest Ophthalmol Vis Sci 2012; 53:3207-14. [PMID: 22599586 DOI: 10.1167/iovs.12-9423] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Recently, insertion of immuno-modulatory or anti-apoptotic genes into corneal endothelial cells (HCECs) came into focus. Basic FGF-2 occurs in one secreted (low molecular weight, LMW, 18 kD) and four nuclear (high molecular weight, HMW, 22-34 kD) isoforms. HMW isoforms are known differentiation and survival factors, while LMW FGF-2 is a known mitogen. The effect of FGF-2 overexpression of each of the five known isoforms on HCEC cell survival after lentiviral gene transfer in different culture media was investigated. METHODS Cells were transduced with lentiviral vectors encoding for each of the five FGF-2 isoforms. Transduction efficiency and expression of individual FGF-2 isoforms was assessed by marker gene transfer and western blotting. Primary HCECs were cultured and transduced in four different media previously described for HCEC cultivation or corneal organ cultivation. Cytotoxic effect of virus infection and a possible rescue effect of FGF-2 overexpression were determined by resazurin conversion assay. RESULTS Transduction with FGF-2 encoding lentiviral vectors resulted in overexpression of the respective isoform in all tested cell populations. Western blotting after total cell lysis proved nuclear localization of transgenic HMW isoforms. Overexpression of HMW FGF-2-especially 34 kD FGF-2-reduced lentiviral cytotoxicity, while overexpression of LMW FGF-2 aggravated viral cytotoxicity. CONCLUSIONS Cytotoxicity of lentiviral gene transfer in corneal endothelial cells may be reduced by using bicistronic vectors that encode for the target gene and the 34-kD isoform of human FGF-2. Such cotransduction of a survival factor may increase cell survival after gene transfer, thereby improving gene therapeutic approaches.
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Affiliation(s)
- Monika Valtink
- Institute of Anatomy, Medical Faculty Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, Dresden, Germany.
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Mergler S, Valtink M, Taetz K, Sahlmüller M, Fels G, Reinach PS, Engelmann K, Pleyer U. Characterization of transient receptor potential vanilloid channel 4 (TRPV4) in human corneal endothelial cells. Exp Eye Res 2011; 93:710-9. [DOI: 10.1016/j.exer.2011.09.021] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Revised: 08/29/2011] [Accepted: 09/07/2011] [Indexed: 11/26/2022]
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Valtink M, Stanke N, Knels L, Engelmann K, Funk RHW, Lindemann D. Pseudotyping and culture conditions affect efficiency and cytotoxicity of retroviral gene transfer to human corneal endothelial cells. Invest Ophthalmol Vis Sci 2011; 52:6807-13. [PMID: 21757582 DOI: 10.1167/iovs.11-7710] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To evaluate retroviral vectors as a tool to transduce normal human corneal endothelial cells (HCECs) and to optimize transduction to increase gene transfer efficiency. METHODS Enhanced green fluorescent protein (EGFP) encoding retroviral vectors based on HIV-1 or murine leukemia virus (MLV), pseudotyped with either vesicular stomatitis virus glycoprotein (VSV-G) or a modified foamy virus envelope protein (FV Env), and prototype foamy virus (PFV) were produced. Transduction was performed in four HCEC culture media that were previously described for specific cultivation of HCECs or organ culture of donor corneas, namely enriched HCEC growth medium F99(HCEC), its unsupplemented basal medium F99, MEM + 2% fetal calf serum (FCS) (MEM), and Human Endothelial-SFM (SFM). Transduction efficiency was evaluated by marker gene transfer assay, and cytotoxic effects of virus infection were evaluated by means of resazurin conversion assay. RESULTS PFV- and HIV-1-based vectors showed superior transduction efficiency compared with MLV-based vectors. Pseudotyping with a modified FV Env increased transduction efficiency compared with pseudotyping with VSV-G. In medium SFM, transduction efficiency of PFV, HIV-1-/FV Env, and MLV-based vectors was markedly reduced compared with the other culture media. When cells were cultured in F99-based media, cell viability was reduced by retroviral transduction compared with uninfected or mock infected controls, but remained unaffected when cells were cultured in SFM and was even increased when cells were cultured in MEM. CONCLUSIONS HIV-1-based vectors pseudotyped with FV Env can efficiently be used to transduce primary HCECs in vitro. However, transduction efficiency is dependent on culture conditions and impairs metabolic activity and viability of HCECs in vitro.
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Affiliation(s)
- Monika Valtink
- Institute of Anatomy, Medical Faculty Carl Gustav Carus, TU Dresden, Dresden, Germany.
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Knels L, Valtink M, Roehlecke C, Lupp A, de la Vega J, Mehner M, Funk RHW. Blue light stress in retinal neuronal (R28) cells is dependent on wavelength range and irradiance. Eur J Neurosci 2011; 34:548-58. [PMID: 21781192 DOI: 10.1111/j.1460-9568.2011.07790.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The aim of our study was to elucidate the role of wavelength and irradiance in blue light retinal damage. We investigated the impact of blue light emitted from light-emitting diode (LED) modules with peaks at either 411nm (half bandwidth 17nm) or 470nm (half bandwidth 25nm) at defined irradiances of 0.6, 1.5 and 4.5W/m(2) for 411nm and 4.5W/m(2) for 470nm on retinal neuronal (R28) cells in vitro. We observed a reduction in metabolic activity and transmembrane potential of mitochondria when cells were irradiated at 411nm at higher irradiances. Furthermore, production of mitochondrial superoxide radicals increased significantly when cells were irradiated with 411nm light at 4.5W/m(2) . In addition, such irradiation caused an activation of the antioxidative glutathion system. Using vital staining, flow cytometry and western blotting, we were able to show that apoptosis only took place when cells were exposed to 411nm blue light at higher irradiances; necrosis was not observed. Enhanced caspase-3 cleavage product levels confirmed that this effect was dependent on light irradiance. Significant alterations of the above-mentioned parameters were not observed when cells were irradiated with 471nm light despite a high irradiance of 4.5W/m(2) , indicating that the cytotoxic effect of blue light is highly dependent on wavelength. The observed phenomena in R28 cells at 411nm (4.5W/m(2) ) point to an apoptosis pathway elicited by direct mitochondrial damage and increased oxidative stress. Thus, light of 411nm should act via impairment of mitochondrial function by compromising the metabolic situation of these retinal neuronal cells.
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Affiliation(s)
- Lilla Knels
- Department of Anatomy, Medical Faculty Carl Gustav Carus, TU Dresden, Fetscherstraße 74, 01307 Dresden, Germany.
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Abstract
BACKGROUND Endothelial keratoplasty is a promising surgical procedure which may replace penetrating keratoplasty in cases of endothelial cell diseases of the cornea. This method may thereby help to prevent postoperative astigmatism and transplant rejection. METHODS AND RESULTS A survey of publications reporting about results after endothelial keratoplasty shows that the main problem of this transplantation technique is a postoperative endothelial cell loss which is comparable to or even higher than that observed in penetrating keratoplasty. Improving surgical techniques led to a reduction of the endothelial cell loss, however, cell-based strategies to prevent postoperative cell loss or to enhance the cell densities of donor corneas or endothelial lamellae are rare. DISCUSSION This review presents an overview of clinical results after endothelial keratoplasty. Current strategies in the field of cell biology and tissue cultivation of corneal endothelial cells, genetic manipulation of the corneal endothelium and tissue engineering strategies aiming at the production of transplantable endothelial cell sheets are described. CONCLUSION The limited availability of donor corneas makes it mandatory to develop methods in the field of tissue engineering in order to improve corneal endothelial cell survival or to increase corneal endothelial cell density, using interdisciplinary approaches.
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Affiliation(s)
- K Engelmann
- Augenklinik, Klinikum Chemnitz gGmbH, Flemmingstrasse 2, Chemnitz.
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Ulbrich S, Friedrichs J, Valtink M, Murovski S, Franz CM, Müller DJ, Funk RHW, Engelmann K. Retinal pigment epithelium cell alignment on nanostructured collagen matrices. Cells Tissues Organs 2011; 194:443-56. [PMID: 21411961 DOI: 10.1159/000323653] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/14/2010] [Indexed: 11/19/2022] Open
Abstract
We investigated attachment and migration of human retinal pigment epithelial cells (primary, SV40-transfected and ARPE-19) on nanoscopically defined, two-dimensional matrices composed of parallel-aligned collagen type I fibrils. These matrices were used non-cross-linked (native) or after riboflavin/UV-A cross-linking to study cell attachment and migration by time-lapse video microscopy. Expression of collagen type I and IV, MMP-2 and of the collagen-binding integrin subunit α(2) were examined by immunofluorescence and Western blotting. SV40-RPE cells quickly attached to the nanostructured collagen matrices and aligned along the collagen fibrils. However, they disrupted both native and cross-linked collagen matrices within 5 h. Primary RPE cells aligned more slowly without destroying either native or cross-linked substrates. Compared to primary RPE cells, ARPE-19 cells showed reduced alignment but partially disrupted the matrices within 20 h after seeding. Expression of the collagen type I-binding integrin subunit α(2) was highest in SV40-RPE cells, lower in primary RPE cells and almost undetectable in ARPE-19 cells. Thus, integrin α(2) expression levels directly correlated with the degree of cell alignment in all examined RPE cell types. Specific integrin subunit α(2)-mediated matrix binding was verified by preincubation with an α(2)-function-blocking antibody, which impaired cell adhesion and alignment to varying degrees in primary and SV40-RPE cells. Since native matrices supported extended and directed primary RPE cell growth, optimizing the matrix production procedure may in the future yield nanostructured collagen matrices serving as transferable cell sheet carriers.
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Affiliation(s)
- Stefan Ulbrich
- Institute of Anatomy, Biotechnology Center, TU Dresden, Dresden, Germany
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Gruschwitz R, Friedrichs J, Valtink M, Franz C, Müller DJ, Funk RHW, Engelmann K. Author Response: Effects of Fibroblastic and Endothelial Extracellular Matrices on Corneal Endothelial Cells. Invest Ophthalmol Vis Sci 2010. [DOI: 10.1167/iovs.10-6526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
| | - Jens Friedrichs
- Cellular Machines Group, Biotechnology Center, and 3Department of Biosystems, Science, and Engineering, the Swiss Federal Institute of Technology (ETH) Zurich, Basel, Switzerland
| | | | - Clemens Franz
- the DFG Center for Functional Nanostructures, Institute of Technology, University of Karlsruhe, Karlsruhe, Germany; and
| | - Daniel J. Müller
- Cellular Machines Group, Biotechnology Center, and 5CRTD/DFG-Center for Regenerative Therapies Dresden–Cluster of Excellence, TU Dresden, Dresden, Germany; 3Department of Biosystems, Science, and Engineering, the Swiss Federal Institute of Technology (ETH
| | - Richard H. W. Funk
- Institute of Anatomy, 5CRTD/DFG-Center for Regenerative Therapies Dresden–Cluster of Excellence, TU Dresden, Dresden, Germany
| | - Katrin Engelmann
- CRTD/DFG-Center for Regenerative Therapies Dresden–Cluster of Excellence, TU Dresden, Dresden, Germany; 6Department of Ophthalmology, Klinikum Chemnitz GmbH, Chemnitz, Germany
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Jackel T, Knels L, Valtink M, Funk RHW, Engelmann K. Serum-free corneal organ culture medium (SFM) but not conventional minimal essential organ culture medium (MEM) protects human corneal endothelial cells from apoptotic and necrotic cell death. Br J Ophthalmol 2010; 95:123-30. [DOI: 10.1136/bjo.2010.183418] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Gruschwitz R, Friedrichs J, Valtink M, Franz CM, Müller DJ, Funk RHW, Engelmann K. Alignment and cell-matrix interactions of human corneal endothelial cells on nanostructured collagen type I matrices. Invest Ophthalmol Vis Sci 2010; 51:6303-10. [PMID: 20631237 DOI: 10.1167/iovs.10-5368] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To use nanoscopically defined, two-dimensional matrices assembled from aligned collagen type I fibrils as a sheet substratum for in vitro cultivation of human corneal endothelial cells (HCECs). To assess the effect of matrix architecture on HCEC morphology and to characterize integrin-mediated HCEC-matrix interaction. METHODS Cell alignment and cell-matrix interactions of primary HCECs and three different immortalized HCEC populations on native and UV-cross-linked collagen type I matrices were examined by time-lapse microscopy. Specific integrin α(2)β(1) binding to the collagen matrix was demonstrated using a function-blocking α(2) antibody. Integrin α(2) subunit expression levels of the four HCEC populations were analyzed by Western blot analysis. RESULTS All HCEC populations aligned along the oriented collagen fibrils. Primary HCECs and, to a lesser extent, the other tested HCEC populations exerted high traction forces, leading to progressive matrix destruction. Cross-linking of the collagen matrices considerably increased matrix stability. Integrin subunit α(2) expression levels of the four cell types correlated with the degree of cell alignment and exertion of traction forces. In turn, blocking integrin subunit α(2) reduced cell alignment and prevented matrix destruction. CONCLUSIONS HCECs align directionally along parallel arrays of collagen type I fibrils. The interactions of HCECs with collagen type I are primarily mediated by integrin α(2)β(1). Integrin subunit α(2) levels correlate with matrix contraction and subsequent destruction. Sustained cultivation of HCECs on ultrathin collagen matrices thus requires matrix cross-linking and moderate integrin α(2)β(1) expression levels.
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Affiliation(s)
- Rita Gruschwitz
- Institute of Anatomy, Medical Faculty Carl Gustav Carus, TU Dresden, Dresden, Germany
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Abstract
The retinal pigment epithelium (RPE) is a monolayer of cells adjacent to the photoreceptors of the retina. It plays a crucial role in maintaining photoreceptor health and survival. Degeneration or dysfunction of the RPE can lead to photoreceptor degeneration and as a consequence to visual impairment. The most common diseased state of the RPE becomes manifest in age-related macular degeneration, an increasing cause of blindness in the elderly. RPE cells are therefore of great interest to researchers working in the field of tissue engineering and cell transplantation. In fact, studies in animal models have proven that the transplantation of RPE cells can delay the course of photoreceptor degenerative diseases. Although first attempts to transplant RPE cells into the subretinal space in human individuals suffering from age-related macular degeneration were less successful, RPE cell transplantation is still favored as a future therapeutic option, and much work is done to develop and design cell transplants. Cell banking is a prerequisite to have well-differentiated and characterized cells at hand when needed for research purposes, but also for therapeutic approaches. In this chapter the authors will describe methods to isolate, culture and preserve adult human RPE cells for the purpose of RPE cell banking.
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Valtink M. Zwei immortalisierte klonale Zelllinien des adulten humanen kornealen Endothels mit unterschiedlichem Phänotyp. Klin Monbl Augenheilkd 2008. [DOI: 10.1055/s-0028-1104724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Götze T, Valtink M, Nitschke M, Gramm S, Hanke T, Engelmann K, Werner C. Cultivation of an immortalized human corneal endothelial cell population and two distinct clonal subpopulations on thermo-responsive carriers. Graefes Arch Clin Exp Ophthalmol 2008; 246:1575-83. [DOI: 10.1007/s00417-008-0904-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2008] [Revised: 06/26/2008] [Accepted: 06/28/2008] [Indexed: 10/21/2022] Open
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Karl MO, Kroeger W, Wimmers S, Milenkovic VM, Valtink M, Engelmann K, Strauss O. Endogenous Gas6 and Ca2+ -channel activation modulate phagocytosis by retinal pigment epithelium. Cell Signal 2008; 20:1159-68. [PMID: 18395422 DOI: 10.1016/j.cellsig.2008.02.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2007] [Revised: 01/27/2008] [Accepted: 02/06/2008] [Indexed: 11/25/2022]
Abstract
Mutation or loss of MerTK as well as deficiency of alphavbeta5-integrins, gives rise to retinal-degeneration due to inefficient phagocytosis of photoreceptor outer-segment fragments by the retinal pigment epithelium (RPE). This study shows that Gas6 expressed endogenously by human RPE promotes phagocytosis. The RPE expresses Gas6 more highly in vivo and in serum-reduced conditions in vitro than in high-serum conditions, suggesting a negative-feedback control. An antibody-blockage approach revealed that Gas6-expressing RPE phagocytizes photoreceptor outer-segment fragments due to stimulation of MerTK by endogenous Gas6 in vitro. MerTK- and Gas6-antibodies reduced phagocytosis. Blocking L-type Ca(2+)-channels with nifedipine inhibited MerTK dependent phagocytosis in vitro. Application of integrin inhibitory, soluble, RGD-containing peptides or soluble vitronectin reduced L-type Ca(2+)-channel currents in RPE. Herbimycin A, which reduces phosphorylation of integrin receptor-associated proteins and decreases L-type Ca(2+)-channel currents in RPE, eliminates the inhibiting vitronectin effect and abolishes phagocytosis. Thus, Gas6-promoted phagocytosis was inhibited by L-type Ca(2+)-channel blockage, which in turn may be activated by integrin receptor stimulation. These results suggest that L-type Ca(2+)-channels could be regulated downstream of both MerTK and alphavbeta5-integrin, indicating that the binding and uptake mechanisms of phagocytosis are part of a converging pathway.
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Affiliation(s)
- Mike O Karl
- University Eye Hospital Hamburg, Martinistrasse 52, 20246 Hamburg, Germany.
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Valtink M, Gruschwitz R, Funk RHW, Engelmann K. Two clonal cell lines of immortalized human corneal endothelial cells show either differentiated or precursor cell characteristics. Cells Tissues Organs 2008; 187:286-94. [PMID: 18196893 DOI: 10.1159/000113406] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/26/2007] [Indexed: 12/13/2022] Open
Abstract
Access to primary human corneal endothelial cells (HCEC) is limited and donor-derived differences between cultures exacerbate the issue of data reproducibility, whereas cell lines can provide sufficient numbers of homogenous cells for multiple experiments. An immortalized HCEC population was adapted to serum-free culture medium and repeated cloning was performed. Clonally grown cells were propagated under serum-free conditions and growth curves were recorded. Cells were characterized immunocytochemically for junctional proteins, collagens, Na,K-ATPase and HCEC-specific 9.3.E-antigen. Ultrastructure was monitored by scanning and transmission electron microscopy. Two clonal cell lines, HCEC-B4G12 and HCEC-H9C1, could be isolated and expanded, which differed morphologically: B4G12 cells were polygonal, strongly adherent and formed a strict monolayer, H9C1 cells were less adherent and formed floating spheres. The generation time of B4G12 cells was 62.26 +/- 14.5 h and that of H9C1 cells 44.05 +/- 5.05 h. Scanning electron microscopy revealed that B4G12 cells had a smooth cell surface, while H9C1 cells had numerous thin filopodia. Both cell lines expressed ZO-1 and occludin adequately, and little but well detectable amounts of connexin-43. Expression of HCEC-specific 9.3.E-antigen was found commensurately in both cell lines, while expression of Na,K-ATPase alpha1 was higher in H9C1 cells than in B4G12 cells. B4G12 cells expressed collagen IV abundantly and almost no collagen III, while H9C1 cells expressed both collagens at reasonable amounts. It is concluded that the clonal cell line B4G12 represents an ideal model of differentiated HCEC, while H9C1 may reflect features of developing or transitional HCEC.
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Affiliation(s)
- Monika Valtink
- Tissue Engineering Laboratories, Biotechnology Center, University of Technology, Dresden, Germany.
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Nitschke M, Gramm S, Götze T, Valtink M, Drichel J, Voit B, Engelmann K, Werner C. Thermo-responsive poly(NiPAAm-co-DEGMA) substrates for gentle harvest of human corneal endothelial cell sheets. J Biomed Mater Res A 2007; 80:1003-10. [PMID: 17187393 DOI: 10.1002/jbm.a.31098] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Gentle harvesting of corneal endothelial cell sheets grown in culture is of interest for the development of cornea replacement strategies. Thin films of a fast responding copolymer of N-isopropylacrylamide (NiPAAm) and diethyleneglycol methacrylate (DEGMA) with a phase transition temperature of 32 degrees C were prepared and evaluated for that purpose. The polymer layers were immobilized onto fluorocarbon substrates using low pressure argon plasma treatment. Cell culture and detachment experiments were performed with L929 mouse fibroblasts and human corneal endothelial cells (HCEC) at standard conditions. The hydrogel-coated supports were found to permit adhesion, spreading, and proliferation of both cell types. Harvesting of cell sheets was achieved upon lowering the temperature to about 30 degrees C. The formation of a closed monolayer as a crucial prerequisite for maintaining ionic pump function in HCEC was proven by ZO-1 immunostainung. Labeling of fibronectin indicated that the vast majority of the extracellular matrix is detached from the hydrogel coatings together with the cell layer. Inspired by this result, the reuse of the hydrogel-coated culture carriers was investigated confirming the suitability of the substrates for repeated cell harvesting. Altogether, the introduced thermoresponsive coating was found advantageous for the efficient generation of HCEC sheets and will be further utilized in transplantation strategies.
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Affiliation(s)
- Mirko Nitschke
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials Dresden, Hohe Strasse 6, 01069 Dresden, Germany.
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Valtink M, Engelmann K. Serum-free cultivation of adult normal human choroidal melanocytes. Graefes Arch Clin Exp Ophthalmol 2007; 245:1487-94. [PMID: 17458555 DOI: 10.1007/s00417-007-0588-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2006] [Revised: 02/27/2007] [Accepted: 03/19/2007] [Indexed: 10/23/2022] Open
Abstract
BACKGROUND Cultures of normal choroidal melanocytes are useful in vitro models for the study of melanocyte biology. Current protocols involve the supplementation of culture media with serum, toxins, and phorbol esters, the latter being known as tumour-inducing agents. We therefore sought to establish a protocol to cultivate normal human choroidal melanocytes (NHCMs) without these supplements. METHODS NHCMs were isolated by dispase II treatment, after isolation of retinal pigment epithelial (RPE) cells, and seeded in serum-free Melanocyte Growth Medium M2 in uncoated T25 cell culture flasks. Purity of the established cultures was proven by immunocytochemistry. Morphology of the cultured cells was evaluated throughout the entire cultivation period. Eventually, cells were cryopreserved in liquid nitrogen. RESULTS The cultures underwent at least 11.5 +/- 4.5 doublings before they became senescent or culture was deliberately terminated. Mean generation time was 95.0 +/- 27.7 h. After cryopreservation, generation time was markedly increased, but proliferative capacity of the cells was not impaired. Cultured cells showed bipolar to dendritic morphology; sometimes flattened triangular cells were seen in the cultures. Cultured cells lost pigment after initial seeding but displayed continuous melanogenesis. All cultures stained positive for HMB45 antigen and S-100 and negative for RPE-specific cytokeratins 8, 18. Only few cultures contained single cells that were weakly positive for matrix metalloproteinase (MMP)-2 or MMP-9. CONCLUSIONS The cultivation protocol yields pure cultures of NHCMs that can successfully be maintained for several months without the use of serum, tumour-inducing substances, or toxins.
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Affiliation(s)
- Monika Valtink
- Tissue Engineering Laboratories, Biotechnological Centre (BIOTEC), University of Technology Dresden, Tatzberg 47-51, 01307 Dresden, Germany.
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Karl MO, Valtink M, Bednarz J, Engelmann K. Cell culture conditions affect RPE phagocytic function. Graefes Arch Clin Exp Ophthalmol 2006; 245:981-91. [PMID: 17177038 DOI: 10.1007/s00417-006-0451-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2006] [Revised: 08/30/2006] [Accepted: 09/11/2006] [Indexed: 10/23/2022] Open
Abstract
BACKGROUND Changes in the phenotype of retinal pigment epithelium (RPE) cells in vitro are associated with medium conditions and changes in function. Main goals in RPE tissue engineering are cell propagation in serum-free defined culture conditions, resulting in cells exhibiting differentiated morphology and functioning in vitro. METHODS To compare the effects of various media and supplements on cell function, an optimized high-throughput phagocytosis assay was developed. Adult human SV40-RPE cells were cultured. Test media included: MEM(E), DMEM, F99, SFM and hSFM, with or without supplements. SNAFL-2 labelled OS were added to RPE in vitro for 4 h and phagocytic binding and uptake were measured. RESULTS RPE phagocytosis was of different magnitude depending on the serum-free basic cell culture media in the following order: hSFM, SFM > DMEM, MEM > F99. Choroid-conditioned medium (ChCM) decreased phagocytosis dose dependently. Whereas 1% retinal extract (RE) supplementation increased, higher concentrations decreased phagocytosis. Addition of 10% FCS increased phagocytosis. 15% ChCM quenched the stimulation induced by 10% FCS, an effect which could be reversed by the addition of 1% RE. CONCLUSIONS Cell culture media and RPE environmental factors exert substantial and differential alteration of RPE phagocytic ability. Phagocytosis in a serum-free defined medium is superior to unsupplemented basic media, but still differs from serum-supplemented media (F99RPE) designed for cell propagation. We conclude that media SFM or hSFM promoted phagocytosis most, and application of FCS or 1% RE supports phagocytosis. Unknown factors from neighbouring tissues (retina and choroid) affect phagocytosis differently, suggesting a role in retinal pathogenesis. The results will support identification of specific environmental factors and facilitate design of cell culture media.
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Affiliation(s)
- Mike O Karl
- Department of Ophthalmology, Cornea Bank, University Eye Clinic Eppendorf, Martinistrasse 52, Hamburg 20246, Germany.
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Abstract
BACKGROUND The human corneal endothelium has a limited proliferative capacity in vivo. Until now it has only been possible to replace damaged endothelium by transplantation of a donor cornea. After establishing methods for the isolation and in vitro cultivation of human corneal endothelial cells (HCEC), transplantation of these cells may be an alternative therapeutic option. MATERIALS AND METHODS In this review methods for the in vitro cultivation of HCEC and their transplantation onto the Descemet membrane of donor corneas are described. RESULTS In vitro proliferation of human adult corneal endothelial cells was achieved by the development of defined cell culture conditions, including supplementation of culture medium with specified growth factors. Dependent on the culture conditions, in vitro cultured endothelial cells showed phenotypic changes and different proliferative behaviour. The propagation of corneal endothelial cells in vitro offered the possibility of their transplantation onto donor corneas in an in vitro model. After transplantation, these cells formed a monolayer whose morphology and cell density depended on the differentiation status of the cells in vitro. Highest cell numbers up to 3000 cells/mm2 were achieved using a SV40-transformed HCEC-cell line. Monolayer integrity could be demonstrated by positive staining for integrins and light junction proteins, and pump function of the newly established endothelium was proven by perfusion studies. CONCLUSIONS Methods to transplant HCEC onto human denuded corneas have been successfully established to reconstruct human corneas. Recent developments in genetic manipulation of cells and tissue engineering will be of great help in constructing suitable corneas for keratoplasty. Thus corneal endothelial cell transplantation is one of the promising future possibilities to provide corneas of high quality for patients. Furthermore, improvement of the transplantation technique may lead to a method to directly manipulate the diseased endothelium of patients with corneal endothelial dystrophies.
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Affiliation(s)
- Katrin Engelmann
- University Eye Hospital, University Hospital Carl Gustav Carus at the TU Dresden, Fetscherstrasse 74, Dresden 01307, Germany.
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Warncke B, Valtink M, Weichel J, Engelmann K, Schäfer H. Experimental rat model for therapeutic retinal pigment epithelium transplantation?unequivocal microscopic identification of human donor cells by in situ hybridisation of human-specific Alu sequences. Virchows Arch 2004; 444:74-81. [PMID: 14586651 DOI: 10.1007/s00428-003-0891-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2003] [Accepted: 08/01/2003] [Indexed: 11/29/2022]
Abstract
Transplantation of retinal pigment epithelial (RPE) cells is discussed as a possible therapeutic approach for retinal degeneration. Xenogeneic transplantation of human RPE cells in animal models has been studied extensively. Various methods have been used to identify the graft cells, but these methods interfere with cell behaviour so that the monitored physiological post-transplantation course may be influenced. In the present study, we applied a method for an unequivocal identification of the graft cells without interfering cell metabolism or behaviour using in situ hybridisation (ISH) of human specific Alu sequences. Visualisation of the strong extended nuclear signal of Alu sequences was much easier than that of the small nuclear signals of donor-specific sex chromosome probes. With Alu probe, even single graft cells can be identified and their development can be observed in short-term and long-term studies. With this procedure, we could prove that donor cells were injected correctly into the subretinal space by a special injection technique that we developed previously. In combination with immunohistochemistry, donor cells could be clearly discriminated from macrophages, which contained phagocytosed donor cell fragments. Application of these ISH methods for species-specific identification was valuable for follow-up-studies of RPE transplantation.
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Affiliation(s)
- Beate Warncke
- Department of Pathology, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
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Affiliation(s)
- Katrin Engelmann
- University Eye Hospital Dresden, Fetscherstrasse 74, 01307 Dresden, Germany.
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Hecquet C, Lefevre G, Valtink M, Engelmann K, Mascarelli F. Activation and role of MAP kinase-dependent pathways in retinal pigment epithelium cells: JNK1, P38 kinase, and cell death. Invest Ophthalmol Vis Sci 2003; 44:1320-9. [PMID: 12601065 DOI: 10.1167/iovs.02-0519] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Retinal pigment epithelial (RPE) cell death is an important step in the pathogenesis of ocular diseases. JNK1 and P38 kinase, two stress-activated kinases, play key roles relaying stress signals leading to cell death through cyclin D1 and c-Myc. Recently, stress-activated kinases have been shown to regulate cell proliferation. In the current study, the involvement of the JNK1 and P38 kinase signaling pathways in RPE cell proliferation and death was investigated. METHODS RPE cell proliferation was stimulated with 10% fetal calf serum (FCS). Activation of the JNK1 and P38 kinase cascades and their potential targets was detected by Western blot analysis. Pharmacologic inhibitors and activators, and antisense oligodeoxynucleotides (ODN) directed against the stress kinases were used to analyze the signaling involved in RPE cell death. RESULTS P38 and JNK1 and their respective upstream activating kinases, MKK3/6 and -4, were all transiently activated in FCS-stimulated RPE cell cultures. Ras controlled only the activation of JNK1, whereas Rho transmitted the activation of both JNK1 and P38, suggesting parallel signaling pathways and cross talk between the two kinases. Pharmacologic inhibition of JNK1 did not affect cell proliferation in FCS-stimulated cells. Inactivation of P38 kinase and antisense ODN-induced downregulation of P38 kinase also had no affect on cell proliferation. Long-term, high-level activation of JNK1 and P38 kinase occurred during serum depletion-induced RPE cell death. Overactivation of JNK1 and P38 kinase was also observed during pharmacologically induced cell death, suggesting that this process is common to RPE cell-death-signaling pathways induced by various stress stimuli. Cell death mediated by the overactivation of JNK1 and P38 kinase was cyclin D1- and c-Myc-independent. CONCLUSIONS The inhibition of JNK1 or P38 kinase had no effect on FCS-stimulated proliferation of RPE cells, whereas the overactivation of these two enzymes was involved in RPE cell death in FCS-depleted cultures. Parallel upstream signaling pathways and cross talk between the two kinases suggest that the regulation of signaling in RPE cell death is complex.
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Affiliation(s)
- Christiane Hecquet
- Cordeliers Biomedical Institute, National Institute of Health and Medical Research, Unit 450, National Center for Scientific Research, Paris, France
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Hecquet C, Lefevre G, Valtink M, Engelmann K, Mascarelli F. cAMP inhibits the proliferation of retinal pigmented epithelial cells through the inhibition of ERK1/2 in a PKA-independent manner. Oncogene 2002; 21:6101-12. [PMID: 12203122 DOI: 10.1038/sj.onc.1205765] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2002] [Revised: 05/13/2002] [Accepted: 06/14/2002] [Indexed: 11/09/2022]
Abstract
Retinal pigmented epithelial (RPE) cell integrity is critical to the maintenance of retina functions and RPE cells do not proliferate in adults. The activation of RPE results in cell proliferation which may be associated with proliferative retinopathy and choroidal melanoma. Mitogen-activated protein kinase (MAPK) is believed to be a key participant in the response to mitogenic stimuli. We therefore investigated the involvement of the extracellular signal-regulated protein kinase (ERK) 1 and 2 during the induction of RPE cell proliferation. After foetal calf serum (FCS) stimulation activation of the Ras/Raf/ERK signalling pathway was detected by Western blotting and immunochemistry, with specific anti-phosphosignalling protein antibodies. Pharmacological and antisense (AS) oligonucleotide (ODN) strategies were used to analyse the signalling involved in FCS-induced RPE cell proliferation. Activation of the small G protein Ras and, to a lesser extent of Raf-1, the kinase directly downstream from Ras, was necessary to FCS-induced cell proliferation. MEK1/2 and ERK1/2 were activated during cell proliferation. Inhibition of MEK1/2 with UO 126 completely abolished ERK1/2 activation and reduced cell proliferation by 33-43%. ERK1/2 depletion by an AS ODN approach reduced cell proliferation by 27-33%, confirming the role of ERK1/2 in the FCS stimulation of RPE cells. We also investigated the role of PKA/cAMP, one of the major inhibitory pathways of ERK1/2. PKA blockade did not modify ERK1/2 activation or cell proliferation. In contrast, agents that increased cAMP concentration, abolished RPE proliferation, and MEK/ERK activation. Moreover, inhibition of the cAMP-activated small G protein Rap1, partially reversed the inhibitory effects of cAMP on cell proliferation and MEK/ERK activation. The requirement for Ras and ERK1/2, the lack of ERK1/2 regulation by PKA and the cAMP/Rap1 counter-regulatory pathway for ERK-mediated cell proliferation suggest complex regulation of signalling in RPE cells. These data may have important implications for the development of more selective models for retinal anti-proliferative therapies.
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Affiliation(s)
- Christiane Hecquet
- Centre Biomédical des Cordeliers, INSERM U. 450, affiliée CNRS, 15 rue de l'Ecole de Médecine 75006 Paris, France
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Hecquet C, Lefevre G, Valtink M, Engelmann K, Mascarelli F. Activation and role of MAP kinase-dependent pathways in retinal pigment epithelial cells: ERK and RPE cell proliferation. Invest Ophthalmol Vis Sci 2002; 43:3091-8. [PMID: 12202534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023] Open
Abstract
PURPOSE Retinal pigment epithelial (RPE) cell proliferation plays a key role in the pathogenesis of ocular diseases involving the posterior segment. Mitogen-activated protein kinases (MAPKs) are involved in the control of cell proliferation. This study was conducted to investigate the involvement of the extracellular signal-regulated kinase (ERK) pathway, the major MAPK pathway implicated in cell growth during the induction of RPE cell proliferation. METHODS RPE cell proliferation was stimulated with 10% fetal calf serum (FCS). Activation of the Ras/Raf/MAP kinase-ERK kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling pathway was detected by Western blot analysis and immunochemistry with specific anti-phosphosignaling protein antibodies. Pharmacologic and antisense (AS) oligonucleotide (ODN) strategies were used to analyze the ERK signaling involved in serum-induced cell proliferation. RESULTS FCS (10%) induced more vigorous RPE cell proliferation than did FGF2, VEGF, platelet-derived growth factor (PDGF), or epidermal growth factor (EGF), alone or in combination. Pharmacologic inhibition of Ras and Raf-1 reduced cell proliferation by 67% to 100% and by 62% to 79%, respectively, demonstrating that activation of the Ras/Raf-1 pathway was essential for FCS-induced RPE cell proliferation. MEK1/2, ERK2, and P90 ribosomal S6 kinase (P90(RSK)), the kinases downstream from ERK2, were strongly activated during cell proliferation. Pharmacologic inhibition of MEK1/2 abolished activation of ERK2, but reduced cell proliferation by only 32%, showing that MEK/ERK participates in the signaling involved in RPE cell growth. Both inhibition of ERK2 activation, which reduced cyclin D1 production, and inhibition of cyclin D1 by AS ODN decreased cell proliferation, suggesting that RPE cell proliferation is mediated by cyclin D1 through ERK2. CONCLUSIONS The requirement for Ras and the regulatory role of ERK2 in cyclin D1 production and in cell proliferation suggest that the Ras/Raf/MEK/ERK pathway plays a key role in the control of RPE cell proliferation. These data may have important implications for the development of more selective methods for the inhibition of retinal proliferation.
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Affiliation(s)
- Christiane Hecquet
- Cordeliers Biomedical Institut, National Institute of Health and Medical Research (INSERM) Unit 450, Center for Scientific Research, Paris, France
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Weichel J, Valtink M, Engelmann K, Richard G. Use of an oil-hydraulic microinjection pump for subretinal infusions. Ophthalmic Surg Lasers 2002; 33:340-2. [PMID: 12135000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
The injection of cell suspensions or drugs into the subretinal space is a new promising option of vitreoretinal surgery for the treatment of degenerative retinal disorders. We used a manual oil-hydraulic microinjection pump to subretinally inject suspensions of retinal pigment epithelial cells in Royal College of Surgeons rats and in patients suffering from age-related macular degeneration with geographic atrophy. The histological examination of the treated rat eyes showed that cell suspensions could be placed precisely in the subretinal space. Intra- and postoperative outcome of the patients in the clinical trial revealed no retinal complications during 6 months of follow up. We suggest the oil-hydraulic microinjection pump to be a valuable instrument for controlled and precisely dosed atraumatic infusion or aspiration of small volumes of cell suspensions, fluids or drugs in vitreoretinal surgery.
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Affiliation(s)
- Judith Weichel
- Department of Ophthalmology, University of Hamburg, Germany
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Weichel J, Valtink M, Engelmann K, Richard G. Use of an Oil-Hydraulic Microinjection Pump for Subretinal Infusions. Ophthalmic Surg Lasers Imaging Retina 2002. [DOI: 10.3928/1542-8877-20020701-19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Valtink M, Engelmann K, Strauss O, Krüger R, Löliger C, Ventura AS, Richard G. Physiological features of primary cultures and subcultures of human retinal pigment epithelial cells before and after cryopreservation for cell transplantation. Graefes Arch Clin Exp Ophthalmol 1999; 237:1001-6. [PMID: 10654169 DOI: 10.1007/s004170050336] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND One striking disadvantage of in vitro culturing of human retinal pigment epithelial (RPE) cells is the loss of epithelial differentiation and specific cell function during culture. This may be one of the main reasons for the failure of RPE cell transplantation. The aim of this study was to evaluate cell culture conditions ensuring the maintenance of differentiation and function of RPE cells after subcultivation and storage in liquid nitrogen. METHODS Enzymatically isolated cells were seeded onto coated culture dishes, cultured with a specially formulated improved growth medium until confluence and then cryopreserved in liquid nitrogen for 16-66 months. HLA class I and II typing was performed before cryopreservation and after thawing. Expression of Ca2+ channels in primary, first-passage and cryopreserved RPE cells was studied using the patch-clamp technique. RESULTS After cryopreservation no loss of any HLA antigen was detectable in 12 of 14 cell strains studied. Patch-clamp experiments demonstrated that high-threshold L-type Ca2+ channels, which are typical for freshly isolated cells, could be detected in first-passage and cryopreserved RPE cells only when improved culture conditions were employed, not in conventionally cultured cells. The characteristics of these channels showed little change in subcultured cells compared to primary cultures. CONCLUSION This is the first study showing the maintenance of adult human RPE-specific cell differentiation and characteristics in vitro after primary culture and after cryopreservation using improved cell culture methods. The optimization and quality control of cell culture is an important prerequisite for successful cell transplantation.
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Affiliation(s)
- M Valtink
- Department of Ophthalmology, University of Hamburg, Germany
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Valtink M, Engelmann K, Krüger R, Schellhorn ML, Löliger C, Püschel K, Richard G. [Structure of a cell bank for transplantation of HLA-typed, cryopreserved human adult retinal pigment epithelial cells]. Ophthalmologe 1999; 96:648-52. [PMID: 10552157 DOI: 10.1007/s003470050468] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND The transplantation of retinal pigment epithelial cells (RPE) in patients with age-related macular degeneration is discussed as a future therapy. A cornea bank can serve as a source for cells that can be isolated, cultivated, HLA-typed and cryopreserved for subsequent tissue-compatible transplantation. METHODS RPE cells are isolated enzymatically from donor eyes and are cultured in a specially designed growth medium. After multiplication, one part of the culture is cryopreserved; the other part is subcultured for HLA-typing. Completely typed and morphologically sufficiently well-differentiated cell cultures are registered on a donor list (RPE cell bank) and can be provided for cell transplantations with matching HLA type in patients suffering from RPE degenerative diseases. RESULTS A total of 461 cell cultures have been prepared since 1996; 116 fully typed and well-differentiated cell cultures are stored in our cell bank. Since January 1998 patients who agreed to have an RPE transplantation have been registered on a waiting list. Seven transplantations have already been performed. CONCLUSION RPE cells can be stored cryopreserved in a cell bank and can be kept available for transplantation for a prolonged period of time.
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