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Jandl K, Berg JL, Birnhuber A, Fliesser E, Borek I, Seeliger B, David S, Schmidt JJ, Gorkiewicz G, Zacharias M, Welte T, Olschewski H, Heinemann A, Wygrecka M, Kwapiszewska G. Basement membrane product, endostatin, as a link between inflammation, coagulation and vascular permeability in COVID-19 and non-COVID-19 acute respiratory distress syndrome. Front Immunol 2023; 14:1188079. [PMID: 37283766 PMCID: PMC10241244 DOI: 10.3389/fimmu.2023.1188079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 05/04/2023] [Indexed: 06/08/2023] Open
Abstract
Background Immune cell recruitment, endothelial cell barrier disruption, and platelet activation are hallmarks of lung injuries caused by COVID-19 or other insults which can result in acute respiratory distress syndrome (ARDS). Basement membrane (BM) disruption is commonly observed in ARDS, however, the role of newly generated bioactive BM fragments is mostly unknown. Here, we investigate the role of endostatin, a fragment of the BM protein collagen XVIIIα1, on ARDS associated cellular functions such as neutrophil recruitment, endothelial cell barrier integrity, and platelet aggregation in vitro. Methods In our study we analyzed endostatin in plasma and post-mortem lung specimens of patients with COVID-19 and non-COVID-19 ARDS. Functionally, we investigated the effect of endostatin on neutrophil activation and migration, platelet aggregation, and endothelial barrier function in vitro. Additionally, we performed correlation analysis for endostatin and other critical plasma parameters. Results We observed increased plasma levels of endostatin in our COVID-19 and non-COVID-19 ARDS cohort. Immunohistochemical staining of ARDS lung sections depicted BM disruption, alongside immunoreactivity for endostatin in proximity to immune cells, endothelial cells, and fibrinous clots. Functionally, endostatin enhanced the activity of neutrophils, and platelets, and the thrombin-induced microvascular barrier disruption. Finally, we showed a positive correlation of endostatin with soluble disease markers VE-Cadherin, c-reactive protein (CRP), fibrinogen, and interleukin (IL)-6 in our COVID-19 cohort. Conclusion The cumulative effects of endostatin on propagating neutrophil chemotaxis, platelet aggregation, and endothelial cell barrier disruption may suggest endostatin as a link between those cellular events in ARDS pathology.
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Affiliation(s)
- Katharina Jandl
- Otto Loewi Research Center, Division of Pharmacology, Medical University of Graz, Graz, Austria
- Ludwig Boltzmann Institute for Lung Vascular Research, Graz, Austria
| | - Johannes Lorenz Berg
- Ludwig Boltzmann Institute for Lung Vascular Research, Graz, Austria
- Otto Loewi Research Center, Division of Physiology and Pathophysiology, Medical University of Graz, Graz, Austria
| | - Anna Birnhuber
- Ludwig Boltzmann Institute for Lung Vascular Research, Graz, Austria
- Otto Loewi Research Center, Division of Physiology and Pathophysiology, Medical University of Graz, Graz, Austria
| | | | - Izabela Borek
- Ludwig Boltzmann Institute for Lung Vascular Research, Graz, Austria
| | - Benjamin Seeliger
- Department of Respiratory Medicine/Infectious Diseases, Hannover Medical School, Member of the German Lung Center (DZL), Hannover, Germany
| | - Sascha David
- Institute of Intensive Care, University Hospital Zurich, Zurich, Switzerland
| | - Julius J. Schmidt
- Department of Nephrology and Hypertension, Hannover Medical School, Hannover, Germany
| | - Gregor Gorkiewicz
- Diagnostic and Research Institute of Pathology, Medical University Graz, Graz, Austria
| | - Martin Zacharias
- Diagnostic and Research Institute of Pathology, Medical University Graz, Graz, Austria
| | - Tobias Welte
- Department of Respiratory Medicine/Infectious Diseases, Hannover Medical School, Member of the German Lung Center (DZL), Hannover, Germany
| | - Horst Olschewski
- Ludwig Boltzmann Institute for Lung Vascular Research, Graz, Austria
- Division of Pulmonology, Medical University of Graz, Graz, Austria
| | - Akos Heinemann
- Otto Loewi Research Center, Division of Pharmacology, Medical University of Graz, Graz, Austria
| | - Malgorzata Wygrecka
- Center for Infection and Genomics of the Lung, Universities of Giessen and Marburg Lung Center, Member of the German Lung Center (DZL), Giessen, Germany
- Institute for Lung Health, Member of the German Lung Center (DZL), Giessen, Germany
| | - Grazyna Kwapiszewska
- Ludwig Boltzmann Institute for Lung Vascular Research, Graz, Austria
- Otto Loewi Research Center, Division of Physiology and Pathophysiology, Medical University of Graz, Graz, Austria
- Institute for Lung Health, Member of the German Lung Center (DZL), Giessen, Germany
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2
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LeVine DN, Cianciolo RE, Linder KE, Bizikova P, Birkenheuer AJ, Brooks MB, Salous AK, Nordone SK, Bellinger DA, Marr H, Jones SL, Fischer TH, Deng Y, Mazepa M, Key NS. Endothelial alterations in a canine model of immune thrombocytopenia. Platelets 2017; 30:88-97. [PMID: 29182425 DOI: 10.1080/09537104.2017.1378807] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Bleeding heterogeneity amongst patients with immune thrombocytopenia (ITP) is poorly understood. Platelets play a role in maintaining endothelial integrity, and variable thrombocytopenia-induced endothelial changes may influence bleeding severity. Platelet-derived endothelial stabilizers and markers of endothelial integrity in ITP are largely underexplored. We hypothesized that, in a canine ITP model, thrombocytopenia would lead to alterations in the endothelial ultrastructure and that the Von Willebrand factor (vWF) would serve as a marker of endothelial injury associated with thrombocytopenia. Thrombocytopenia was induced in healthy dogs with an antiplatelet antibody infusion; control dogs received an isotype control antibody. Cutaneous biopsies were obtained prior to thrombocytopenia induction, at platelet nadir, 24 hours after nadir, and on platelet recovery. Cutaneous capillaries were assessed by electron microscopy for vessel thickness, the number of pinocytotic vesicles, the number of large vacuoles, and the number of gaps between cells. Pinocytotic vesicles are thought to represent an endothelial membrane reserve that can be used for repair of damaged endothelial cells. Plasma samples were assessed for vWF. ITP dogs had significantly decreased pinocytotic vesicle numbers compared to control dogs (P = 0.0357) and the increase in plasma vWF from baseline to 24 hours correlated directly with the endothelial large vacuole score (R = 0.99103; P < 0.0001). This direct correlation between plasma vWF and the number of large vacuoles, representing the vesiculo-vacuolar organelle (VVO), a permeability structure, suggests that circulating vWF could serve as a biomarker for endothelial alterations and potentially a predictor of thrombocytopenic bleeding. Overall, our results indicate that endothelial damage occurs in the canine ITP model and variability in the degree of endothelial damage may account for differences in the bleeding phenotype among patients with ITP.
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Affiliation(s)
- Dana N LeVine
- a Department of Veterinary Clinical Sciences , Iowa State University , Ames , IA , USA.,b Department of Clinical Sciences , North Carolina State University, College of Veterinary Medicine , Raleigh , NC , USA.,h Department of Pathology and Laboratory Animal Medicine , University of North Carolina , Chapel Hill , NC , USA
| | - Rachel E Cianciolo
- c Department of Veterinary Biosciences , The Ohio State University , Columbus , OH , USA
| | - Keith E Linder
- d Department of Population Health and Pathobiology , North Carolina State University, College of Veterinary Medicine , Raleigh , NC , USA
| | - Petra Bizikova
- b Department of Clinical Sciences , North Carolina State University, College of Veterinary Medicine , Raleigh , NC , USA
| | - Adam J Birkenheuer
- b Department of Clinical Sciences , North Carolina State University, College of Veterinary Medicine , Raleigh , NC , USA
| | - Marjory B Brooks
- e Department of Population Medicine and Diagnostic Sciences , Cornell University, College of Veterinary Medicine , Ithaca , NY , USA
| | - Abdelghaffar K Salous
- f Division of Cardiovascular Medicine , The Gill Heart Institute, University of Kentucky , Lexington , KY , USA
| | - Shila K Nordone
- g Department of Molecular Biomedical Sciences , North Carolina State University, College of Veterinary Medicine , Raleigh , NC , USA
| | - Dwight A Bellinger
- h Department of Pathology and Laboratory Animal Medicine , University of North Carolina , Chapel Hill , NC , USA
| | - Henry Marr
- b Department of Clinical Sciences , North Carolina State University, College of Veterinary Medicine , Raleigh , NC , USA
| | - Sam L Jones
- b Department of Clinical Sciences , North Carolina State University, College of Veterinary Medicine , Raleigh , NC , USA
| | - Thomas H Fischer
- h Department of Pathology and Laboratory Animal Medicine , University of North Carolina , Chapel Hill , NC , USA
| | - Yu Deng
- i Department of Biostatistics , University of North Carolina , Chapel Hill , NC , USA
| | - Marshall Mazepa
- h Department of Pathology and Laboratory Animal Medicine , University of North Carolina , Chapel Hill , NC , USA
| | - Nigel S Key
- h Department of Pathology and Laboratory Animal Medicine , University of North Carolina , Chapel Hill , NC , USA.,j Department of Medicine , University of North Carolina , Chapel Hill , NC , USA
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3
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Parris GE. A Hypothesis Concerning the Biphasic Dose-response of Tumors to Angiostatin and Endostatin. Dose Response 2015; 13:10.2203_dose-response.14-020.Parris. [PMID: 26675544 PMCID: PMC4674172 DOI: 10.2203/dose-response.14-020.parris] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
This manuscript proposes a hypothesis to explain the U-shaped dose-response observed for angiostatin and other high-molecular-weight drugs in various anti-cancer bio-assays. The dose-response curves for angiostatin and endostatin (measured as suppression of tumor growth) go through an optimum (i.e., minimum tumor growth) and then becomes less effective at higher doses. The literature suggests that at lower doses the primary action of these high-molecular-weight drugs is to counteract the angiogenic effects of vascular endothelial growth factor (VEGF). To do this, the drugs must pass out of the blood vessel and enter the extra-cellular matrix (ECM) where VEGF induces the growth and fusion of tip cells. Ironically, VEGF actually facilitates access of the drugs to the ECM by making the vascular endothelium leaky. At higher doses, the high-molecular-weight drugs seem to reverse VEGF-induced permeability of the endothelium. Thus, at high dose rates, it is hypothesized that the drugs are not able to enter the ECM and block the angiogenic effects of VEGF there. As a result, high doses of the drugs do not suppress vascularization of the tumor or tumor growth. Moreover, if the permeability of the vessels is suppressed, the VEGF released by the stroma is concentrated in the ECM where it amplifies the angiogenic activity around the tumor.
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Affiliation(s)
- George E Parris
- Montgomery College, Department of Chemistry, Rockville, MD, USA
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4
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Bai YJ, Huang LZ, Zhou AY, Zhao M, Yu WZ, Li XX. Antiangiogenesis Effects of Endostatin in Retinal Neovascularization. J Ocul Pharmacol Ther 2013; 29:619-26. [PMID: 23545016 DOI: 10.1089/jop.2012.0225] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Yu-jing Bai
- Key Laboratory of Vision Loss and Restoration, Ministry of Education, Department of Ophthalmology, Peking University People's Hospital, Beijing, People's Republic of China
| | - Lv-zhen Huang
- Key Laboratory of Vision Loss and Restoration, Ministry of Education, Department of Ophthalmology, Peking University People's Hospital, Beijing, People's Republic of China
| | - Ai-yi Zhou
- Key Laboratory of Vision Loss and Restoration, Ministry of Education, Department of Ophthalmology, Peking University People's Hospital, Beijing, People's Republic of China
| | - Min Zhao
- Key Laboratory of Vision Loss and Restoration, Ministry of Education, Department of Ophthalmology, Peking University People's Hospital, Beijing, People's Republic of China
| | - Wen-zhen Yu
- Key Laboratory of Vision Loss and Restoration, Ministry of Education, Department of Ophthalmology, Peking University People's Hospital, Beijing, People's Republic of China
| | - Xiao-xin Li
- Key Laboratory of Vision Loss and Restoration, Ministry of Education, Department of Ophthalmology, Peking University People's Hospital, Beijing, People's Republic of China
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A peptide derived from laminin-γ3 reversibly impairs spermatogenesis in rats. Nat Commun 2013; 3:1185. [PMID: 23149730 PMCID: PMC3538133 DOI: 10.1038/ncomms2171] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Accepted: 09/26/2012] [Indexed: 01/06/2023] Open
Abstract
Cellular events that occur across the seminiferous epithelium of the mammalian testis during spermatogenesis are tightly coordinated by biologically active peptides released from laminin chains. Laminin-γ3 domain IV (Lam γ3 DIV) is released at the apical ectoplasmic specialization (ES) during spermiation and mediates restructuring of the blood-testis barrier (BTB), which facilitates the transit of preleptotene spermatocytes. Here we determine the biologically active domain in Lam γ3 DIV, which we designate F5-peptide, and show that overexpression of this domain, or the use of a synthetic F5-peptide, in Sertoli cells with an established functional BTB reversibly perturbs BTB integrity in vitro and in rat testis in vivo. This effect is mediated via changes in protein distribution at the Sertoli and Sertoli-germ cell-cell interface and by phosphorylation of focal adhesion kinase at Tyr407. The consequences are perturbed organization of actin filaments in Sertoli cells, disruption of the BTB and spermatid loss. The impairment of spermatogenesis suggests that this laminin peptide fragment may serve as a contraceptive in male rats.
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Klaassen I, Van Noorden CJF, Schlingemann RO. Molecular basis of the inner blood-retinal barrier and its breakdown in diabetic macular edema and other pathological conditions. Prog Retin Eye Res 2013; 34:19-48. [PMID: 23416119 DOI: 10.1016/j.preteyeres.2013.02.001] [Citation(s) in RCA: 465] [Impact Index Per Article: 42.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 12/19/2012] [Accepted: 02/01/2013] [Indexed: 12/16/2022]
Abstract
Breakdown of the inner endothelial blood-retinal barrier (BRB), as occurs in diabetic retinopathy, age-related macular degeneration, retinal vein occlusions, uveitis and other chronic retinal diseases, results in vasogenic edema and neural tissue damage, causing loss of vision. The central mechanism of altered BRB function is a change in the permeability characteristics of retinal endothelial cells caused by elevated levels of growth factors, cytokines, advanced glycation end products, inflammation, hyperglycemia and loss of pericytes. Subsequently, paracellular but also transcellular transport across the retinal vascular wall increases via opening of endothelial intercellular junctions and qualitative and quantitative changes in endothelial caveolar transcellular transport, respectively. Functional changes in pericytes and astrocytes, as well as structural changes in the composition of the endothelial glycocalyx and the basal lamina around BRB endothelium further facilitate BRB leakage. As Starling's rules apply, active transcellular transport of plasma proteins by the BRB endothelial cells causing increased interstitial osmotic pressure is probably the main factor in the formation of macular edema. The understanding of the complex cellular and molecular processes involved in BRB leakage has grown rapidly in recent years. Although appropriate animal models for human conditions like diabetic macular edema are lacking, these insights have provided tools for rational design of drugs aimed at restoring the BRB as well as for design of effective transport of drugs across the BRB, to treat the chronic retinal diseases such as diabetic macular edema that affect the quality-of-life of millions of patients.
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Affiliation(s)
- Ingeborg Klaassen
- Ocular Angiogenesis Group, Department of Ophthalmology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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7
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Campbell M, Humphries P. The Blood-Retina Barrier. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013. [DOI: 10.1007/978-1-4614-4711-5_3] [Citation(s) in RCA: 139] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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8
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Campbell M, Humphries P. Size-selective and in vitro assessment of inner blood retina barrier permeability. Methods Mol Biol 2011; 763:355-67. [PMID: 21874464 DOI: 10.1007/978-1-61779-191-8_24] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Assessment of tight junction integrity in vitro is fundamental when studying molecular processes that may be implicated in barrier dysfunction. At the blood brain and inner blood retina barrier (BBB and iBRB, respectively) adjacent endothelial cells lining the microvasculature have been shown to have very low rates of fluid phase transcytosis and high electrical resistances, due in part to the expression of tight junction proteins at the apical periphery of these cells. While these high electrical resistances are difficult to achieve in vitro, owing to complex interactions of endothelial cells in vivo with astrocytes and pericytes, it is possible to make an assessment of paracellular permeability when cells are analysed on a number of different fronts. In this regard, we will outline here a method for determining trans-endothelial electrical resistance, tracer molecule diffusion, and tight junction protein localization in primary cultures of bovine retinal microvascular endothelial cells. This system allows for the screening of a wide range of pro- and anti-angiogenic molecules in an in vitro model of the iBRB and can accurately assess the role individual tight junction proteins play in maintaining tight junction integrity in response to various cell stimuli.
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Affiliation(s)
- Matthew Campbell
- UCD School of Biomolecular Biomedical Sciences, Conway Institute, University College Dublin, Dublin, Ireland.
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9
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Tolstanova G, Deng X, Khomenko T, Garg P, Paunovic B, Chen L, Sitaraman SV, Shiloach J, Szabo S, Sandor Z. Role of anti-angiogenic factor endostatin in the pathogenesis of experimental ulcerative colitis. Life Sci 2010; 88:74-81. [PMID: 21047522 DOI: 10.1016/j.lfs.2010.10.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Revised: 09/26/2010] [Accepted: 10/22/2010] [Indexed: 01/03/2023]
Abstract
AIMS Vascular endothelial growth factor (VEGF) and pathologic angiogenesis have been demonstrated to play a pathogenic role in the development and progression of inflammatory bowel disease. Thus, we hypothesized that the potent anti-angiogenic factor endostatin might play a beneficial role in experimental ulcerative colitis (UC). MAIN METHODS We used three animal models of UC: (1) induced by 6% iodoacetamide (IA) in rats, or (2) by 3% dextran sulfate sodium (DSS) in matrix metalloproteinase-9 (MMP-9) knockout (KO) and wild-type mice, and (3) interleukin-10 (IL-10) KO mice. Groups of MMP-9 KO mice with DSS-induced UC were treated with endostatin or water for 5days. KEY FINDINGS We found concomitant upregulation of VEGF, PDGF, MMP-9 and endostatin in both rat and mouse models of UC. A positive correlation between the levels of endostatin or VEGF and the sizes of colonic lesions was seen in IA-induced UC. The levels and activities of MMP-9 were also significantly increased during UC induced by IA and IL-10 KO. Deletion of MMP-9 decreased the levels of endostatin in both water- and DSS-treated MMP-9 KO mice. Treatment with endostatin significantly improved DSS-induced UC in MMP-9 KO mice. SIGNIFICANCE 1) Concomitantly increased endostatin is a defensive response to the increased VEGF in UC, 2) MMP-9 is a key enzyme to generate endostatin which may modulate the balance between VEGF and endostatin during experimental UC, and 3) endostatin treatment plays a beneficial role in UC. Thus, anti-angiogenesis seems to be a new therapeutic option for UC.
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Affiliation(s)
- Ganna Tolstanova
- Diagnostic & Molecular Medicine, Health Care Group, VA Medical Center, Long Beach, CA, USA
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Xu W, Ye P, Li Z, Shi J, Wang W, Yao K. Endostar, a recently introduced recombinant human endostatin, inhibits proliferation and migration through regulating growth factors, adhesion factors and inflammatory mediators in choroid-retinal endothelial cells. Mol Biol 2010. [DOI: 10.1134/s0026893310040138] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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11
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Campbell M, Ozaki E, Humphries P. Systemic delivery of therapeutics to neuronal tissues: a barrier modulation approach. Expert Opin Drug Deliv 2010; 7:859-69. [DOI: 10.1517/17425247.2010.490554] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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El Sanharawi M, Kowalczuk L, Touchard E, Omri S, de Kozak Y, Behar-Cohen F. Protein delivery for retinal diseases: from basic considerations to clinical applications. Prog Retin Eye Res 2010; 29:443-65. [PMID: 20398784 DOI: 10.1016/j.preteyeres.2010.04.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Because the eye is protected by ocular barriers but is also easily accessible, direct intravitreous injections of therapeutic proteins allow for specific and targeted treatment of retinal diseases. Low doses of proteins are required in this confined environment and a long time of residency in the vitreous is expected, making the eye the ideal organ for local proteic therapies. Monthly intravitreous injection of Ranibizumab, an anti-VEGF Fab has become the standard of care for patients presenting wet AMD. It has brought the proof of concept that administering proteins into the physiologically low proteic concentration vitreous can be performed safely. Other antibodies, Fab, peptides and growth factors have been shown to exert beneficial effects on animal models when administered within the therapeutic and safe window. To extend the use of such biomolecules in the ophthalmology practice, optimization of treatment regimens and efficacy is required. Basic knowledge remains to be increased on how different proteins/peptides penetrate into the eye and the ocular tissues, distribute in the vitreous, penetrate into the retinal layers and/or cells, are eliminated from the eye or metabolized. This should serve as a basis for designing novel drug delivery systems. The later should be non-or minimally invasive and should allow for a controlled, scalable and sustained release of the therapeutic proteins in the ocular media. This paper reviews the actual knowledge regarding protein delivery for eye diseases and describes novel non-viral gene therapy technologies particularly adapted for this purpose.
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Affiliation(s)
- M El Sanharawi
- Inserm, UMRS 872, Centre de Recherche des Cordeliers, Paris, France
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An experimental platform for systemic drug delivery to the retina. Proc Natl Acad Sci U S A 2009; 106:17817-22. [PMID: 19822744 DOI: 10.1073/pnas.0908561106] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Degenerative retinopathies, including age-related macular degeneration, diabetic retinopathy, and hereditary retinal disorders--major causes of world blindness--are potentially treatable by using low-molecular weight neuroprotective, antiapoptotic, or antineovascular drugs. These agents are, however, not in current systemic use owing to, among other factors, their inability to passively diffuse across the microvasculature of the retina because of the presence of the inner blood-retina barrier (iBRB). Moreover, preclinical assessment of the efficacies of new formulations in the treatment of such conditions is similarly compromised. We describe here an experimental process for RNAi-mediated, size-selective, transient, and reversible modulation of the iBRB in mice to molecules up to 800 Da by suppression of transcripts encoding claudin-5, a protein component of the tight junctions of the inner retinal vasculature. MRI produced no evidence indicative of brain or retinal edema, and the process resulted in minimal disturbance of global transcriptional patterns analyzed in neuronal tissue. We show that visual function can be improved in IMPDH1(-/-) mice, a model of autosomal recessive retinitis pigmentosa, and that the rate of photoreceptor cell death can be reduced in a model of light-induced retinal degeneration by systemic drug delivery after reversible barrier opening. These findings provide a platform for high-throughput drug screening in models of retinal degeneration, and they ultimately could result in the development of a novel "humanized" approach to therapy for conditions with little or no current forms of treatment.
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Campbell M, Collery R, McEvoy A, Gardiner TA, Stitt AW, Brankin B. Involvement of MAPKs in Endostatin-Mediated Regulation of Blood-Retinal Barrier Function. Curr Eye Res 2009; 31:1033-45. [PMID: 17169842 DOI: 10.1080/02713680601013025] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE This study aimed to evaluate the effects of endostatin on tight junction (TJ) integrity in retinal microvascular endothelial cells (RMECs) in vitro and in vivo. Moreover, it was hypothesized that endostatin-induced occludin upregulation regulated VEGF165-mediated increases in endothelial cell permeability and involved activation of the MAPK signaling cascade. Endostatin is a 20-kDa fragment of collagen XVIII that has been shown to be efficacious in the eye by preventing retinal neovascularization. Endostatin is a specific inhibitor of endothelial cell proliferation, migration, and angiogenesis and has been reported to reverse VEGF-mediated increases in vasopermeability and to promote integrity of the blood-retinal barrier (BRB). In order to determine the mechanism of endostatin action on BRB integrity, we have examined the effects of endostatin on a number of intracellular pathways implicated in endothelial cell physiology. METHODS C57/Bl6 mice were injected with VEGF165 and/or endostatin, and the distribution of occludin staining was determined using retinal flatmounts. Western blot analysis of RMECs treated with VEGF165 and/or endostatin was used to determine changes in occludin expression and p38 MAPK and extracellular regulated kinase (ERK1/ERK2 MAPK) activation, while FD-4 flux across the RMEC monolayer was used to determine changes in paracellular permeability. RESULTS Endostatin prevented the discontinuous pattern of occludin staining observed at the retinal blood vessels of mice administered an intraocular injection of VEGF165. It was shown that endostatin activated p38 MAPK 5 min after addition to RMECs and continued to do so for approximately 30 min. Endostatin was also shown to activate ERK1/ERK2 5 min after addition and continued to do so, albeit with less potency, up to and including 15 min after addition. Inhibition of p38 MAPK and ERK1/ERK2 prevented endostatin's ability to upregulate levels of occludin expression. Inhibition of these key signaling molecules was shown to prevent endostatin's ability to protect against VEGF165-mediated increases in paracellular permeability in vitro. However, it appears that p38 MAPK may play a more important role in VEGF-mediated permeability, as inhibition of ERK1/ERK2 will not prevent VEGF165-mediated permeability compared with control (untreated) cells or cells treated with both a p38 MAPK inhibitor and VEGF165. CONCLUSIONS Occludin is important for the maintenance of tight junction integrity in vivo. In a p38 MAPK and ERK1/ERK2 dependent manner, endostatin was shown to upregulate the levels of expression of the tight junction protein occludin. Inhibition of these key MAPK components may prevent endostatin's ability to decrease VEGF165-induced paracellular permeability.
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Affiliation(s)
- Matthew Campbell
- UCD School of Biomolecular Biomedical Sciences, Conway Institute, University College Dublin, Dublin, Ireland.
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Klaassen I, Hughes JM, Vogels IM, Schalkwijk CG, Van Noorden CJ, Schlingemann RO. Altered expression of genes related to blood–retina barrier disruption in streptozotocin-induced diabetes. Exp Eye Res 2009; 89:4-15. [DOI: 10.1016/j.exer.2009.01.006] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Revised: 10/31/2008] [Accepted: 01/12/2009] [Indexed: 11/28/2022]
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Canning P, Glenn JV, Hsu DK, Liu FT, Gardiner TA, Stitt AW. Inhibition of advanced glycation and absence of galectin-3 prevent blood-retinal barrier dysfunction during short-term diabetes. EXPERIMENTAL DIABETES RESEARCH 2008; 2007:51837. [PMID: 17641742 PMCID: PMC1880865 DOI: 10.1155/2007/51837] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2006] [Accepted: 02/02/2007] [Indexed: 01/13/2023]
Abstract
Breakdown of the inner blood-retinal barrier (iBRB) occurs early in diabetes and is central to the development of sight-threatening diabetic macular edema (DME) as retinopathy progresses. In the current study, we examined how advanced glycation end products (AGEs) forming early in diabetes could modulate vasopermeability factor expression in the diabetic retina and alter inter-endothelial cell tight junction (TJ) integrity leading to iBRB dysfunction. We also investigated the potential for an AGE inhibitor to prevent this acute pathology and examined a role of the AGE-binding protein galectin-3 (Gal-3) in AGE-mediated cell retinal pathophysiology. Diabetes was induced in C57/BL6 wild-type (WT) mice and in Gal-3−/− transgenic mice. Blood glucose was monitored and AGE levels were quantified by ELISA and immunohistochemistry. The diabetic groups were subdivided, and one group was treated with the AGE-inhibitor pyridoxamine (PM) while separate groups of WT and Gal-3−/− mice were maintained as nondiabetic controls. iBRB integrity was assessed by Evans blue assay alongside visualisation of TJ protein complexes via occludin-1 immunolocalization in retinal flat mounts. Retinal expression levels of the vasopermeability factor VEGF were quantified using real-time RT-PCR and ELISA. WT diabetic mice showed significant AGE -immunoreactivity in the retinal microvasculature and also showed significant iBRB breakdown (P < .005). These diabetics had higher VEGF mRNA and protein expression in comparison to controls (P < .01). PM-treated diabetics had normal iBRB function and significantly reduced diabetes-mediated VEGF expression. Diabetic retinal vessels showed disrupted TJ integrity when compared to controls, while PM-treated diabetics demonstrated near-normal configuration. Gal-3−/− mice showed significantly less diabetes-mediated iBRB dysfunction, junctional disruption, and VEGF expression changes than their WT counterparts. The data suggests an AGE-mediated disruption of iBRB via upregulation of VEGF in the diabetic retina, possibly modulating disruption of TJ integrity, even after acute diabetes. Prevention of AGE formation or genetic deletion of Gal-3 can effectively prevent these acute diabetic retinopathy changes.
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Affiliation(s)
- Paul Canning
- Centre for Vision Science, Queen's University Belfast, Royal Victoria Hospital, Grosvenor Road, Belfast BT12 6BA, Northern Ireland, UK
| | - Josephine V. Glenn
- Centre for Vision Science, Queen's University Belfast, Royal Victoria Hospital, Grosvenor Road, Belfast BT12 6BA, Northern Ireland, UK
| | - Daniel K. Hsu
- Department of Dermatology, School of Medicine, University of California, Sacramento, CA 95616, USA
| | - Fu-Tong Liu
- Department of Dermatology, School of Medicine, University of California, Sacramento, CA 95616, USA
| | - Tom A. Gardiner
- Centre for Vision Science, Queen's University Belfast, Royal Victoria Hospital, Grosvenor Road, Belfast BT12 6BA, Northern Ireland, UK
| | - Alan W. Stitt
- Centre for Vision Science, Queen's University Belfast, Royal Victoria Hospital, Grosvenor Road, Belfast BT12 6BA, Northern Ireland, UK
- *Alan W. Stitt:
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17
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Marneros AG, She H, Zambarakji H, Hashizume H, Connolly EJ, Kim I, Gragoudas ES, Miller JW, Olsen BR. Endogenous endostatin inhibits choroidal neovascularization. FASEB J 2007; 21:3809-18. [PMID: 17526870 DOI: 10.1096/fj.07-8422com] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Endostatin, a fragment of the basement membrane component collagen XVIII, exhibits antiangiogenic properties in vitro and in vivo when high doses are administered. It is not known whether endogenous endostatin at physiological levels has a protective role as an inhibitor of pathological angiogenesis, such as choroidal neovascularization (CNV) in age-related macular degeneration. Using a laser injury model, we induced CNV in mice lacking collagen XVIII/endostatin and in control mice. CNV lesions in mutant mice were approximately 3-fold larger than in control mice and showed increased vascular leakage. These differences were independent of age-related changes at the choroid-retina interface. Ultrastructural analysis of the choroidal vasculature in mutant mice excluded morphological vascular abnormalities as a cause for the larger CNV lesions. When recombinant endostatin was administered to collagen XVIII/endostatin-deficient mice, CNV lesions were similar to those seen in control mice. In control mice treated with recombinant endostatin, CNV lesions were almost undetectable. These findings demonstrate that endogenous endostatin is an inhibitor of induced angiogenesis and that administration of endostatin potently inhibits CNV growth and vascular leakage. Endostatin may have a regulatory role in the pathogenesis of CNV and could be used therapeutically to inhibit growth and leakage of CNV lesions.
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Affiliation(s)
- Alexander G Marneros
- Department of Developmental Biology, Harvard School of Dental Medicine, 188 Longwood Ave., Boston, MA 02115, USA.
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18
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Chandra A, Barillas S, Suliman A, Angle N. A novel fluorescence-based cellular permeability assay. ACTA ACUST UNITED AC 2007; 70:329-33. [PMID: 16962665 DOI: 10.1016/j.jbbm.2006.07.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2006] [Revised: 05/25/2006] [Accepted: 07/10/2006] [Indexed: 10/24/2022]
Abstract
Vascular permeability is a pathologic process in many disease states ranging from metastatic progression of malignancies to ischemia-reperfusion injury. In order to more precisely study tissue, and more specifically cell layer permeability, our goal was to create a fluorescence-based assay which could quantify permeability without radioactivity or electrical impedance measurements. Human aortic endothelial cells were grown in monolayer culture on Costar-Transwell clear polyester membrane 6-well cell culture inserts. After monolayer integrity was confirmed, vascular endothelial growth factor (VEGF(165)) at varying concentrations with a fixed concentration of yellow-green fluorescent 0.04 microm carboxylate-modified FluoSpheres microspheres were placed in the luminal chamber and incubated for 24 h. When stimulated with VEGF(165) at 20, 40, 80, and 100 ng/ml, this assay system was able to detect increases in trans-layer flux of 8.2+/-2.4%, 16.0+/-3.7%, 41.5+/-4.9%, and 58.6+/-10.1% for each concentration, respectively. This represents the first fluorescence-based permeability assay with the sensitivity to detect changes in the permeability of a cell layer to fluid flux independent of protein flux; as well as being simpler and safer than previous radioactive-and impedance-based permeability assays. With the application of this in vitro assay to a variety of pathologic conditions, both the dynamics and physiology relating to cellular permeability can be more fully investigated.
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Affiliation(s)
- Ankur Chandra
- Section of Vascular and Endovascular Surgery, Department of Surgery, Univeristy of California, San Diego Medical Center, 200 West Arbor Drive, San Diego, CA 92103-8402, USA
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19
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Wang YL, Hui YN, Guo B, Ma JX. Strengthening tight junctions of retinal microvascular endothelial cells by pericytes under normoxia and hypoxia involving angiopoietin-1 signal way. Eye (Lond) 2007; 21:1501-10. [PMID: 17332770 DOI: 10.1038/sj.eye.6702716] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
PURPOSE To determine the effects of pericytes and angiopoietin-1 on the expression of occludin and zonula occludens-1 (ZO-1) in retinal endothelial cells (ECs) under both normoxic and hypoxic conditions. METHODS Rat primary retinal microvascular ECs were cultured under normoxia or hypoxia in either absence or presence of pericytes conditioned medium (PCM). PCM was pretreated with or without angiopoietin-1 neutralizing antibody. Immuofluorescent staining, Western blot and RT-PCR were used to detect the alterations of occludin and ZO-1 expression. RESULTS Under normoxia, PCM strengthened occludin and ZO-1 immunofluorescent staining at cytomembrane as well as increased their expression at both protein and mRNA level. When pretreated with angiopoietin-1 neutralizing antibody, occludin upregulation induced by PCM was significantly blocked at protein level (62%) and mRNA level (34%). Under hypoxia, the continuity of occludin and ZO-1 staining at cell boundaries was disrupted consistent with a decrease of their protein level by 31 and 27%, respectively. Also occludin and ZO-1 mRNA level decreased by 46 and 57%, respectively. PCM was observed to partially increase expression of occludin at protein and mRNA level. Angiopoietin-1 antibody slightly inhibited (16%) PCM induced occludin mRNA increase under hypoxia. CONCLUSION Pericytes improved the integrity of endothelial barrier through inducing occludin and ZO-1 expression at protein and mRNA level under normoxia. Under hypoxia, pericytes could partially reverse occludin decrease. These protecting effects of pericytes on endothelial barrier were at least in part mediated by angiopoietin-1.
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Affiliation(s)
- Y L Wang
- Department of Ophthalmology, Xijing Hospital, the Fourth Military Medical University, Xi'an, China.
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20
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Tanabe K, Maeshima Y, Ichinose K, Kitayama H, Takazawa Y, Hirokoshi K, Kinomura M, Sugiyama H, Makino H. Endostatin peptide, an inhibitor of angiogenesis, prevents the progression of peritoneal sclerosis in a mouse experimental model. Kidney Int 2006; 71:227-38. [PMID: 17191085 DOI: 10.1038/sj.ki.5002040] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Peritoneal sclerosis is a major and serious complication in patients on long-term continuous ambulatory peritoneal dialysis (PD). The involvement of angiogenesis and proangiogenic factors such as vascular endothelial growth factor (VEGF)-A in progressing peritoneal sclerosis has been reported. We previously reported the therapeutic efficacy of endostatin peptide, a potent inhibitor of angiogenesis derived from type XVIII collagen, in a mouse diabetic nephropathy model. Here, we examined the therapeutic effect of endostatin peptide in preventing progression in a mouse peritoneal sclerosis model. Male ICR mice received intraperitoneal injections of chlorhexidine gluconate (CG) every other day to induce peritoneal sclerosis. Endostatin peptide (1 or 4 mg/kg/day) was administered via subcutaneously implanted osmotic minipumps. Peritoneal sclerosis (day 24) was significantly suppressed by endostatin peptide in a dose-dependent manner. Peritoneal accumulation of type III collagen was significantly suppressed by endostatin peptide. Increase in the number of CD31(+) blood vessels, F4/80(+) monocyte/macrophage accumulation, and 5-bromodeoxyuridine(+) proliferating cells was significantly inhibited by endostatin peptide. Increase in peritoneal expression of VEGF-A, profibrotic transforming growth factor-beta1, and alpha-smooth muscle actin was suppressed by endostatin peptide. Immunoreactivity for endogenous endostatin (whole molecule) and endostatin receptor alpha5beta1-integrin was increased and colocalized to CD31(+) blood vessels in the thickened peritonea of CG-injected mice. These results demonstrate the potential use of antiangiogenic endostatin peptide as a novel therapeutic agent in preventing peritoneal sclerosis, a severe complication in patients undergoing long-term PD.
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Affiliation(s)
- K Tanabe
- Department of Medicine and Clinical Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
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21
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Orlova VV, Economopoulou M, Lupu F, Santoso S, Chavakis T. Junctional adhesion molecule-C regulates vascular endothelial permeability by modulating VE-cadherin-mediated cell-cell contacts. ACTA ACUST UNITED AC 2006; 203:2703-14. [PMID: 17116731 PMCID: PMC2118160 DOI: 10.1084/jem.20051730] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We recently reported that junctional adhesion molecule (JAM)-C plays a role in leukocyte transendothelial migration. Here, the role of JAM-C in vascular permeability was investigated in vitro and in vivo. As opposed to macrovascular endothelial cells that constitutively expressed JAM-C in cell–cell contacts, in quiescent microvascular endothelial cells, JAM-C localized mainly intracellularly, and was recruited to junctions upon short-term stimulation with vascular endothelial growth factor (VEGF) or histamine. Strikingly, disruption of JAM-C function decreased basal permeability and prevented the VEGF- and histamine-induced increases in human dermal microvascular endothelial cell permeability in vitro and skin permeability in mice. Permeability increases are essential in angiogenesis, and JAM-C blockade reduced hyperpermeability and neovascularization in hypoxia-induced retinal angiogenesis in mice. The underlying mechanisms of the JAM-C–mediated increase in endothelial permeability were studied. JAM-C was essential for the regulation of endothelial actomyosin, as revealed by decreased F-actin, reduced myosin light chain phosphorylation, and actin stress fiber formation due to JAM-C knockdown. Moreover, the loss of JAM-C expression resulted in stabilization of VE-cadherin–mediated interendothelial adhesion in a manner dependent on the small GTPase Rap1. Together, through modulation of endothelial contractility and VE-cadherin–mediated adhesion, JAM-C helps to regulate vascular permeability and pathologic angiogenesis.
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Affiliation(s)
- Valeria V Orlova
- Experimental Immunology Branch, National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
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22
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Balaggan KS, Binley K, Esapa M, MacLaren RE, Iqball S, Duran Y, Pearson RA, Kan O, Barker SE, Smith AJ, Bainbridge JWB, Naylor S, Ali RR. EIAV vector-mediated delivery of endostatin or angiostatin inhibits angiogenesis and vascular hyperpermeability in experimental CNV. Gene Ther 2006; 13:1153-65. [PMID: 16572190 DOI: 10.1038/sj.gt.3302769] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We evaluated the efficacy of equine infectious anaemia virus (EIAV)-based lentiviral vectors encoding endostatin (EIAV.endostatin) or angiostatin (EIAV.angiostatin) in inhibiting angiogenesis and vascular hyperpermeability in the laser-induced model of choroidal neovascularisation (CNV). Equine infectious anaemia virus.endostatin, EIAV.angiostatin or control (EIAV.null) vectors were administered into the subretinal space of C57Bl/6J mice. Two weeks after laser injury CNV areas and the degree of vascular hyperpermeability were measured by image analysis of in vivo fluorescein angiograms. Compared with EIAV.null-injected eyes, EIAV.endostatin resulted in a 59.5% (P<0.001) reduction in CNV area and a reduction in hyperpermeability of 25.6% (P<0.05). Equine infectious anaemia virus.angiostatin resulted in a 50.0% (P<0.05) reduction in CNV area and a 23.9% (P<0.05) reduction in hyperpermeability. Equine infectious anaemia virus.endostatin, but not EIAV.angiostatin significantly augmented the frequency of apoptosis within the induced CNV as compared with injected controls. TdT-dUTP terminal nick end labeling analysis 5 weeks post-injection, and histological and retinal flatmount analysis 12 months post-injection revealed no evidence of vector- or transgene expression-related deleterious effects on neurosensory retinal cells, or mature retinal vasculature in non-lasered eyes. Highly expressing EIAV-based vectors encoding endostatin or angiostatin effectively control angiogenesis and hyperpermeability in experimental CNV without long-term deleterious effects, supporting the use of such a strategy in the management of patients with exudative age-related macular degeneration.
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Affiliation(s)
- K S Balaggan
- Division of Molecular Therapy, Institute of Ophthalmology, London, UK.
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Economopoulou M, Bdeir K, Cines DB, Fogt F, Bdeir Y, Lubkowski J, Lu W, Preissner KT, Hammes HP, Chavakis T. Inhibition of pathologic retinal neovascularization by alpha-defensins. Blood 2005; 106:3831-8. [PMID: 16123222 PMCID: PMC1895098 DOI: 10.1182/blood-2005-03-0889] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Proliferative retinopathies, such as those complicating prematurity and diabetes, are major causes of blindness. A prominent feature of these retinopathies is excessive neovascularization, which is orchestrated by the hypoxia-induced vascular endothelial growth factor (VEGF) stimulating endothelial cells and the integrin-mediated adhesive interactions of endothelial cells with extracellular matrix components such as fibronectin (FN). Recently, we demonstrated that alpha-defensins interfere with alpha5beta1-FN interactions and dependent endothelial cell functions. Here, alpha-defensins were studied in hypoxia-induced proliferative retinopathy. In vitro, alpha-defensins specifically inhibited alpha5beta1-integrin-dependent migration of bovine retinal endothelial cells (BRECs) to FN, attenuated the VEGF-stimulated increase in endothelial permeability, and blocked BREC proliferation and capillary sprout formation in 3-dimensional fibrin-matrices. An up-regulation of beta1-integrin and FN was observed in the retinal vessels in the mouse model of hypoxia-induced retinal angiogenesis. Systemic and local administration of alpha-defensins reduced retinal neovascularization by 45% and 60%, respectively, and this effect was comparable to the inhibitory effect of alpha5beta1-blocking antibody. alpha-Defensins were detected in human diabetic retinas associated with normal retinal vessels but were absent from proliferative lesions. Together, these data show that alpha-defensins inhibit pathologic retinal neovascularization in vivo and may provide a clinically efficient strategy against proliferative retinopathies.
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Affiliation(s)
- Matina Economopoulou
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Rm 4B17, 10 Center Dr, Bethesda, MD 20892, USA
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