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Salmonella enterica serovar Typhimurium (S Typhimurium) is a Gram-negative bacterium that induces cell death of macrophages as a key virulence strategy. We have previously demonstrated that the induction of macrophage death is dependent on the host's type I IFN (IFN-I) response. IFN-I signaling has been shown to induce tripartite motif (TRIM) 21, an E3 ubiquitin ligase with critical functions in autoimmune disease and antiviral immunity. However, the importance and regulation of TRIM21 during bacterial infection remains poorly understood. In this study, we investigated the role of TRIM21 upon S Typhimurium infection of murine bone marrow-derived macrophages. Although Trim21 expression was induced in an IFN-I-dependent manner, we found that TRIM21 levels were mainly regulated posttranscriptionally. Following TLR4 activation, TRIM21 was transiently degraded via the lysosomal pathway by chaperone-mediated autophagy (CMA). However, S Typhimurium-induced mTORC2 signaling led to phosphorylation of Akt at S473, which subsequently impaired TRIM21 degradation by attenuating CMA. Elevated TRIM21 levels promoted macrophage death associated with reduced transcription of NF erythroid 2-related factor 2 (NRF2)-dependent antioxidative genes. Collectively, our results identify IFN-I-inducible TRIM21 as a negative regulator of innate immune responses to S Typhimurium and a previously unrecognized substrate of CMA. To our knowledge, this is the first study reporting that a member of the TRIM family is degraded by the lysosomal pathway.
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Autofagia Mediada por Chaperones/inmunología , Ribonucleoproteínas/inmunología , Ribonucleoproteínas/metabolismo , Infecciones por Salmonella/inmunología , Infecciones por Salmonella/metabolismo , Salmonella typhimurium/inmunología , Animales , Inmunidad Innata/inmunología , Lisosomas/inmunología , Lisosomas/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Diana Mecanicista del Complejo 2 de la Rapamicina/inmunología , Diana Mecanicista del Complejo 2 de la Rapamicina/metabolismo , Ratones , Ratones Endogámicos C57BL , Factor 2 Relacionado con NF-E2/inmunología , Factor 2 Relacionado con NF-E2/metabolismo , Fosforilación/inmunología , Proteínas Proto-Oncogénicas c-akt/inmunología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/inmunologíaRESUMEN
PURPOSE: The study aims to compare outcomes after deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) in keratoconic eyes with or without previous hydrops. METHODS: Retrospective analysis of 211 eyes who received PK (group 1, n = 74 [history of hydrops: n = 33]) or DALK (group 2, n = 137 [history of hydrops: n = 9]) from 2012 to 2019 at the Department of Ophthalmology, University of Cologne, Germany. Analysis included best spectacle-corrected visual acuity (BSCVA), complications, immune reactions, graft survival and keratometry, and subgroup analyses for subjects with or without previous hydrops. RESULTS: Follow-up was 34.0 ± 23.6 months in group 1 and 30.7 ± 22.5 months in group 2. No significant difference was found in the course of BSCVA between groups 1 and 2 (p = 0.182) and in postoperative BSCVA between eyes with and without previous hydrops, regardless of the surgical method (p = 0.768). Endothelial immune reactions occurred exclusively in group 1 and did not occur more frequently in eyes with previous hydrops (p = 0.377). A higher risk of complications for eyes with previous hydrops was observed (p = 0.022). There was no difference in astigmatism and maximum keratometry (Kmax) preoperatively and postoperatively between eyes with and without history of hydrops. CONCLUSION: The prognosis for visual outcome after keratoplasty including visual acuity, astigmatism, and Kmax for keratoconic eyes with previous hydrops is as good as for keratoconic eyes without previous hydrops, irrespective of the surgical method. However, eyes after hydrops seem to have an increased risk of complications.
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Astigmatismo , Trasplante de Córnea , Queratocono , Edema , Estudios de Seguimiento , Humanos , Queratoplastia Penetrante , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
To discuss and evaluate new technologies for a better diagnosis of corneal diseases and limbal stem cell deficiency, the outcomes of a consensus process within the European Vision Institute (and of a workshop at the University of Cologne) are outlined. Various technologies are presented and analyzed for their potential clinical use also in defining new end points in clinical trials. The disease areas which are discussed comprise dry eye and ocular surface inflammation, imaging, and corneal neovascularization and corneal grafting/stem cell and cell transplantation. The unmet needs in the abovementioned disease areas are discussed, and realistically achievable new technologies for better diagnosis and use in clinical trials are outlined. To sum up, it can be said that there are several new technologies that can improve current diagnostics in the field of ophthalmology in the near future and will have impact on clinical trial end point design.
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Ensayos Clínicos como Asunto , Enfermedades de la Córnea/cirugía , Epitelio Corneal/patología , Limbo de la Córnea/citología , Trasplante de Células Madre/métodos , Células Madre/citología , Congresos como Asunto , Enfermedades de la Córnea/metabolismo , Enfermedades de la Córnea/patología , Epitelio Corneal/metabolismo , Europa (Continente) , HumanosRESUMEN
BACKGROUND: It has been shown experimentally in rodents that removal of the spleen leads to increased rejection of corneal allografts after corneal transplantation (keratoplasty). CASE PRESENTATION: Here, we report a unique case of a splenectomized patient with corneal endothelial dystrophy who underwent posterior lamellar keratoplasty. During follow-up of 4 years, we did not detect any signs of corneal allograft rejection. CONCLUSIONS: Our report indicates that an intact spleen is not necessary for allograft acceptance after posterior lamellar keratoplasty. To the best of our knowledge, this is the first report of a splenectomized patient receiving a (lamellar) corneal transplant.
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Enfermedades de la Córnea/cirugía , Queratoplastia Endotelial de la Lámina Limitante Posterior , Supervivencia de Injerto/inmunología , Huésped Inmunocomprometido , Anciano , Femenino , HumanosRESUMEN
The lymphatic vasculature is - amongst other tasks - essentially involved in inflammation, (auto)immunity, graft rejection and cancer metastasis. The eye is mainly devoid of lymphatic vessels except for its adnexa, the conjunctiva and the limbus. However, several pathologic conditions can result in the secondary ingrowth of lymphatic vessels into physiologically alymphatic parts of the eye such as the cornea or the inner eye. Therefore, the cornea has served as an excellent in vivo model system to study lymphangiogenesis, and findings from such studies have substantially contributed to the understanding of central principles of lymphangiogenesis also with relevance outside the eye. Grafting experiments at the cornea have been extensively used to analyze the role of lymphangiogenesis in transplant immunology. In this regard, we recently demonstrated the crucial role of lymphatic vessels in mediating corneal allograft rejection and could show that antilymphangiogenic therapy increases graft survival. In the field of cancer research, we recently detected tumor-associated lymphangiogenesis in the most common malignant tumors of the eye, such as conjunctival carcinoma and melanoma, and ciliochoroidal melanoma with extraocular extension. These neolymphatics correlate with an increased risk of local recurrence, metastasis and tumor related death, and may offer potential therapeutic targets for the treatment of these tumors. This review will focus on corneal and tumor-associated ocular lymphangiogenesis. First, we will describe common experimentally used corneal lymphangiogenesis models and will recapitulate recent findings regarding the involvement of lymphatic vessels in corneal diseases and transplant immunology. The second part of this article will summarize findings about the participation of tumor-associated lymphangiogenesis in ocular malignancies and their implications for the development of future therapeutic strategies.
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Trasplante de Córnea , Oftalmopatías/patología , Neoplasias del Ojo/patología , Linfangiogénesis/efectos de los fármacos , Animales , Ojo , Oftalmopatías/tratamiento farmacológico , Humanos , Metástasis de la Neoplasia/tratamiento farmacológicoRESUMEN
Neural precursor cells of the ventricular zone give rise to all neurons and glia of the central nervous system and rely for maintenance of their precursor characteristics on the closely related SoxB1 transcription factors Sox1, Sox2 and Sox3. We show in mouse spinal cord that, whereas SoxB1 proteins are usually downregulated upon neuronal specification, they continue to be expressed in glial precursors. In the oligodendrocyte lineage, Sox2 and Sox3 remain present into the early phases of terminal differentiation. Surprisingly, their deletion does not alter precursor characteristics but interferes with proper differentiation. Although a direct influence on myelin gene expression may be part of their function, we provide evidence for another mode of action. SoxB1 proteins promote oligodendrocyte differentiation in part by negatively controlling miR145 and thereby preventing this microRNA from inhibiting several pro-differentiation factors. This study presents one of the few cases in which SoxB1 proteins, including the stem cell factor Sox2, are associated with differentiation rather than precursor functions.
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MicroARNs/genética , Oligodendroglía/metabolismo , Factor de Transcripción SOX9/metabolismo , Factores de Transcripción SOXB1/metabolismo , Animales , Diferenciación Celular , Línea Celular , Regulación del Desarrollo de la Expresión Génica , Células HEK293 , Humanos , Ratones , Células-Madre Neurales , Neurogénesis , Neuroglía/citología , Neuroglía/metabolismo , Regiones Promotoras Genéticas , Ratas , Factor de Transcripción SOX9/biosíntesis , Médula Espinal/citología , Médula Espinal/embriología , Médula Espinal/metabolismoRESUMEN
The role of IL-10, a primarily anti-inflammatory cytokine, in the regulation of inflammatory lymphangiogenesis is undetermined. Herein, we show that IL-10 modulates corneal lymphangiogenesis and resolution of inflammation. IL-10 was not expressed in healthy corneas but was up-regulated in inflamed corneas by infiltrating macrophages. Macrophages up-regulated the expression of prolymphangiogenic vascular endothelial growth factor-C upon stimulation with IL-10. Consistently, corneal inflammation resulted in reduced expression of vascular endothelial growth factor-C and decreased corneal lymphangiogenesis in IL-10-deficient mice (IL-10(-/-)). The effect of IL-10 on lymphangiogenesis was indirect via macrophages, because IL-10 did not directly affect lymphatic endothelial cells. The expression of proinflammatory cytokines and the numbers of infiltrating macrophages increased and remained elevated in inflamed corneas of IL-10(-/-) mice, indicating that IL-10 deficiency led to more severe and prolonged inflammation. The corneal phenotype of IL-10 deficient mice was mimicked in mice with conditional deletion of Stat3 in myeloid cells (lysozyme M Cre mice Stat3(fl/fl) mice), corroborating the critical role of macrophages in the regulation of lymphangiogenesis. Furthermore, local treatment with IL-10 promoted lymphangiogenesis and faster egress of macrophages from inflamed corneas. Taken together, we demonstrate that IL-10 indirectly regulates inflammatory corneal lymphangiogenesis via macrophages. Reduced lymphangiogenesis in IL-10(-/-) and lysozyme M Cre Stat3(fl/fl) mice is associated with more severe inflammatory responses, whereas IL-10 treatment results in faster resolution of inflammation. IL-10 might be used therapeutically to terminate pathological inflammation.
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Neovascularización de la Córnea/inmunología , Interleucina-10/inmunología , Queratitis/inmunología , Queratitis/patología , Macrófagos/inmunología , Animales , Neovascularización de la Córnea/patología , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunohistoquímica , Inflamación/inmunología , Inflamación/patología , Interleucina-10/genética , Interleucina-10/farmacología , Linfangiogénesis , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Reacción en Cadena en Tiempo Real de la Polimerasa , Factor C de Crecimiento Endotelial Vascular/biosíntesisRESUMEN
PURPOSE: To analyze the incidence and clinical course of graft rejection episodes after Descemet membrane endothelial keratoplasty (DMEK). DESIGN: Retrospective analysis of a consecutive, interventional case series. PARTICIPANTS: One thousand eyes that underwent DMEK from July 2011 through August 2015 at the Department of Ophthalmology, University of Cologne. METHODS: All cases with follow-up of at least 1 month were included (mean follow-up, 18.5 months). Patients with a graft rejection episode were followed up for 1 additional year. MAIN OUTCOME MEASURES: Incidence of graft rejection, best spectacle-corrected visual acuity (BSCVA), central corneal thickness (CCT), endothelial cell density (ECD), and need for regraft. RESULTS: Nine hundred five cases met the inclusion criteria. A graft rejection episode developed in 12 patients (estimated probability of rejection at 1 year, 0.9%; at 2 years, 2.3%; at 4 years, 2.3%). At time of rejection, 9 of 12 patients had stopped corticosteroids. Five patients were symptomatic and 7 did not note the rejection episode. Intensified topical corticosteroid therapy was started immediately after diagnosis of rejection. Two eyes decompensated and required a regraft, whereas the remaining 10 eyes required no regraft (BSCVA, 0.27±0.28 logarithm of the minimum angle of resolution [logMAR]; CCT, 554.1±39.1 µm at last visit before rejection vs. BSCVA, 0.21±0.15 logMAR; CCT, 540.0±15.0 µm 3 months after rejection). One year after the rejection episodes, BSCVA and CCT in these eyes remained unchanged when compared with the last visit before rejection (BSCVA, 0.15±0.11 logMAR; CCT, 533.8±26.0 µm). Significant changes were observed for ECD values (1741±274.5 cells/mm2 at last visit before rejection vs. 1356±380.3 cells/mm2 after 3 months [P = 0.04] and 1290±359.0 cells/mm2 after 1 year [P = 0.01]). CONCLUSIONS: The risk for graft rejection after DMEK is low, and an even smaller minority requires a regraft. After intensified local corticosteroid therapy, most patients show stable visual acuity and CCT, although ECD decreases. The occurrence of immune reactions up to 2 years after surgery predominantly in patients not receiving corticosteroids supports the prolonged use of corticosteroids after DMEK.
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Queratoplastia Endotelial de la Lámina Limitante Posterior , Rechazo de Injerto/epidemiología , Rechazo de Injerto/inmunología , Anciano , Anciano de 80 o más Años , Recuento de Células , Enfermedades de la Córnea/cirugía , Pérdida de Celulas Endoteliales de la Córnea/diagnóstico , Paquimetría Corneal , Endotelio Corneal/patología , Femenino , Estudios de Seguimiento , Supervivencia de Injerto/fisiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Probabilidad , Estudios Retrospectivos , Factores de Riesgo , Agudeza Visual/fisiologíaAsunto(s)
Neovascularización de la Córnea , Trasplante de Córnea , Diatermia , Inhibidores de la Angiogénesis/uso terapéutico , Bevacizumab/uso terapéutico , Neovascularización de la Córnea/diagnóstico , Neovascularización de la Córnea/tratamiento farmacológico , Neovascularización de la Córnea/etiología , Estudios de Seguimiento , HumanosRESUMEN
The cornea and the skin are both organs that provide the outer barrier of the body. Both tissues have developed intrinsic mechanisms that protect the organism from a wide range of external threats, but at the same time also enable rapid restoration of tissue integrity and organ-specific function. The easy accessibility makes the skin an attractive model system to study tissue damage and repair. Findings from skin research have contributed to unravelling novel fundamental principles in regenerative biology and the repair of other epithelial-mesenchymal tissues, such as the cornea. Following barrier disruption, the influx of inflammatory cells, myofibroblast differentiation, extracellular matrix synthesis and scar formation present parallel repair mechanisms in cornea and skin wound healing. Yet, capillary sprouting, while pivotal in proper skin wound healing, is a process that is rather associated with pathological repair of the cornea. Understanding the parallels and differences of the cellular and molecular networks that coordinate the wound healing response in skin and cornea are likely of mutual importance for both organs with regard to the development of regenerative therapies and understanding of the disease pathologies that affect epithelial-mesenchymal interactions. Here, we review the principal events in corneal wound healing and the mechanisms to restore corneal transparency and barrier function. We also refer to skin repair mechanisms and their potential implications for regenerative processes in the cornea.
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Córnea/fisiología , Fenómenos Fisiológicos de la Piel , Cicatrización de Heridas , Animales , Diferenciación Celular , Córnea/metabolismo , Córnea/patología , Humanos , Inflamación , Piel/metabolismo , Piel/patologíaRESUMEN
Background Ophthalmology, principally, is a very successful subdiscipline in medicine. Nonetheless, there are still unmet medical needs which necessitate translational research. Methods The funding instrument of a Research Unit (RU) of the German Research Foundation (DFG) is presented as exemplified by the RU 2240 at the Department of Ophthalmology at the University of Cologne. Results The Research Unit integrates different research groups working on pathologic ocular inflammation, macrophages/microglia and (lymph)angiogenesis to collaborate in a synergistic way. Rotation positions allow young clinicians to rotate into research labs for a defined period of time. A Research Unit is also a powerful strategic tool to strengthen clinical and experimental ophthalmology at individual medical faculties. Conclusions The funding instrument of a Research Unit is highly suitable for fostering translational research in a medical subdiscipline such as ophthalmology, supporting the next generation of (clinician) scientists in ophthalmology and finding new cures for our patients.
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Inhibidores de la Angiogénesis/administración & dosificación , Endoftalmitis/tratamiento farmacológico , Endoftalmitis/inmunología , Inmunidad Celular/efectos de los fármacos , Linfangiogénesis/efectos de los fármacos , Linfangiogénesis/inmunología , Investigación Biomédica Traslacional/tendencias , Animales , Modelos Animales de Enfermedad , Inmunidad Celular/inmunología , Inmunoterapia/métodos , Resultado del TratamientoRESUMEN
The lymphatic vascular system-amongst other tasks-is critically involved in the regulation of adaptive immune responses as it provides an important route for APC trafficking to secondary lymphatic organs. In this context, the cornea, which is the transparent and physiologically avascular "windscreen" of the eye, has served as an excellent in vivo model to study the role of the blood and lymphatic vasculature in mediating allogenic immune responses after transplantation. Especially the mouse model of high-risk corneal transplantation, where corneal avascularity is abolished by a severe inflammatory stimulus prior to keratoplasty, allows for comparison to other transplantations performed in primarily vascularized tissues and solid organs. Using this model, we recently demonstrated that especially lymphatic vessels, but not blood vessels, define the high-risk status of vascularized corneas and that anti(lymph)angiogenic treatment significantly promotes corneal allograft survival. Since evidence for lymphangiogenesis and its potential association with graft rejection is nowadays also present in solid organ transplantation, studies are currently addressing the potential benefits of anti(lymph)angiogenic treatment as a novel therapeutic concept also in solid organ grafting with promising initial results.
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Trasplante de Córnea , Rechazo de Injerto/fisiopatología , Linfangiogénesis , Vasos Linfáticos/fisiología , Animales , Humanos , Neovascularización PatológicaAsunto(s)
Queratoplastia Endotelial de la Lámina Limitante Posterior/métodos , Rechazo de Injerto/inmunología , Complicaciones Posoperatorias , Anciano , Recuento de Células , Pérdida de Celulas Endoteliales de la Córnea/patología , Paquimetría Corneal , Femenino , Estudios de Seguimiento , Rechazo de Injerto/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Reoperación , Estudios Retrospectivos , Agudeza Visual/fisiologíaRESUMEN
PURPOSE: To analyze potential alterations in corneal nerve morphology and function in different stages of Fuchs' endothelial corneal dystrophy (FECD). METHODS: Thirty eyes with FECD underwent in vivo confocal microscopy using the Heidelberg Retina Tomograph II (HRT II; Heidelberg Engineering, Heidelberg, Germany) and the Rostock Cornea Module (RCM) to quantify the morphology of the central subbasal corneal nerve plexus (total nerve length, total nerve number, number of main nerve trunks, number of nerve branches) as well as esthesiometry (using the Cochet-Bonnet esthesiometer) of the central cornea to determine central corneal sensation as a measure of nerve function. Findings were correlated with an age-matched control group of 30 healthy individuals. Comparisons to biomicroscopical stage of FECD, visual acuity and central corneal thickness were performed using Spearman correlation. RESULTS: Depending on slit-lamp examination, all 30 eyes were classified into FECD stage 1-4 (stage 1: six eyes; stage 2: 15 eyes; stage 3: six eyes; stage 4: three eyes). Total nerve length (ρ = -0.8, p < 0.001), total nerve number (ρ = -0.7, p < 0.001), number of main nerve trunks (ρ = -0.6, p < 0.001), and number of nerve branches (ρ = -0.7, p < 0.001) decreased significantly with increasing FECD stages. Comparing to the visual acuity, significant positive correlations were found for total nerve length (ρ = 0.5, p = 0.012), total nerve number (ρ = 0.5, p = 0.005), number of main nerve trunks (ρ = 0.4, p = 0.017), and number of nerve branches (ρ = 0.5, p = 0.009). With central corneal thickness, there were significant inverse correlations for total nerve length (ρ = -0.6, p = 0.001), total nerve number (ρ = -0.5, p = 0.012), number of main nerve trunks (ρ = -0.4, p = 0.015), and number of nerve branches (ρ = -0.4, p = 0.017). Central corneal sensation was full in all FECD stage 1, stage 2 and stage 3 eyes, but mildly reduced in FECD stage 4 eyes. CONCLUSIONS: Increasing severity of Fuchs' endothelial corneal dystrophy (FECD) is concurrent with marked attenuation of the density, as well as mild diminishment of the function, of the subbasal corneal nerve plexus in late stage of the disease.
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Córnea/inervación , Enfermedades de los Nervios Craneales/diagnóstico , Distrofia Endotelial de Fuchs/diagnóstico , Nervio Oftálmico/patología , Adulto , Anciano , Anciano de 80 o más Años , Córnea/fisiopatología , Enfermedades de los Nervios Craneales/clasificación , Enfermedades de los Nervios Craneales/fisiopatología , Femenino , Distrofia Endotelial de Fuchs/clasificación , Distrofia Endotelial de Fuchs/fisiopatología , Humanos , Masculino , Microscopía Confocal , Persona de Mediana Edad , Fibras Nerviosas/patología , Red Nerviosa/patología , Estudios Prospectivos , Sensación/fisiologíaRESUMEN
BACKGROUND: The VEGF-A family plays a crucial role in the induction of pathological corneal neovascularization. The role of the different VEGF-A isoforms during lymphangiogenesis is only little-known. Current anti-angiogenic therapies in the eye and other organs inhibit all VEGF-A isoforms, and have effects on both blood and lymphatic vessels. Here we investigate whether selective targeting of the isoform VEGF 165 is able to inhibit corneal lymphangiogenesis under inflammatory conditions. METHODS: The mouse model of suture-induced corneal neovascularization was used to assess the antihem- and antilymphangiogenic effect of topically applied pegaptanib. Corneal blood and lymph vascularized areas were analyzed morphometrically. Furthermore, we analyzed the proliferative effects of VEGF A 121, 165, and 189 on blood and lymphatic endothelial cells (BEC/LEC) via a cell-proliferation assay. RESULTS: Pegaptanib significantly inhibited inflammatory corneal hemangiogenesis (p < 0.01), but not lymphangiogenesis in vivo (p > 0.05), both topically as well as systemically, in the inflamed cornea. In vitro, BECs were more susceptible to pegaptanib than LECs. CONCLUSIONS: Targeting VEGF-A 165 significantly inhibits hem- but not lymphangiogenesis, suggesting VEGF-A 165 to be critical for hem-, but dispensable for lymphangiogenesis, at least in the inflamed cornea.
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Aptámeros de Nucleótidos/farmacología , Neovascularización de la Córnea/prevención & control , Modelos Animales de Enfermedad , Linfangiogénesis/fisiología , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Administración Tópica , Animales , Proliferación Celular/efectos de los fármacos , Neovascularización de la Córnea/metabolismo , Neovascularización de la Córnea/patología , Células Endoteliales/metabolismo , Células Endoteliales/patología , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Glicoproteínas/metabolismo , Proteínas de Transporte de Membrana , Ratones , Ratones Endogámicos BALB C , Soluciones Oftálmicas , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Isoformas de ProteínasRESUMEN
Background: Corneal inflammatory hem- and lymphangiogenesis significantly increase the risk for immune rejection after subsequent allogeneic corneal transplantation. The purpose of this study was to analyze the impact of temporary selective inhibition of lymphangiogenesis after transplantation on graft survival. Methods: Allogeneic transplantation from C57BL/6 mice to BalbC mice was performed as "high-risk" keratoplasty in a prevascularized corneal host bed (suture-induced inflammatory corneal neovascularization). The treatment group received integrin α5ß1-blocking small molecules (JSM6427) at the time of transplantation and for two weeks afterwards. Control mice received a vehicle solution. Grafts were evaluated weekly for graft rejection using an opacity score. At the end of the follow-up, immunohistochemical staining of corneal wholemounts for lymphatic vessels as well as CD11b+ immune cells was performed. Results: Temporary postoperative inhibition of lymphangiogenesis by JSM6427 improved the corneal graft survival significantly. At the end of the follow-up, no significant reduction in CD11b+ immunoreactive cells within the graft compared to controls was found. Conclusions: The significant improvement of corneal graft survival by the selective, temporary postoperative inhibition of lymphangiogenesis after keratoplasty using integrin antagonists shows the impact of lymphatic vessels in the early postoperative phase. Retarding lymphatic vessel ingrowth into the graft might be sufficient for the shift to immunological tolerance in the postoperative period, even after high-risk keratoplasty.
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BACKGROUND: Good vision highly depends on the transparency of the cornea, which is the "windscreen" of the eye. In fact, corneal blindness due to transparency loss is the second most common cause of blindness worldwide, and corneal transplantation is the main cure. Importantly, the cornea is normally avascular but can secondarily be invaded by pathological (blood and lymphatic) vessels due to severe inflammation, and the survival prognosis of a corneal graft mainly depends on the preoperative vascular condition of the recipient's cornea. Whereas transplants placed into avascular recipient beds enjoy long-term survival rates of > 90%, survival rates significantly decrease in pathologically pre-vascularized, so-called high-risk recipients, which account for around 10% of all performed transplants in Germany and > 75% in lower and middle-income countries worldwide. METHODS: This parallel-grouped, open-randomized, multicenter, prospective controlled exploratory investigator-initiated trial (IIT) intends to improve graft survival by preconditioning pathologically vascularized recipient corneas by (lymph)angioregressive treatment before high-risk corneal transplantation. For this purpose, corneal crosslinking (CXL) will be used, which has been shown to potently regress corneal blood and lymphatic vessels. Prior to transplantation, patients will be randomized into 2 groups: (1) CXL (intervention) or (2) no pretreatment (control). CXL will be repeated once if insufficient reduction of corneal neovascularization should be observed. All patients (both groups) will then undergo corneal transplantation. In the intervention group, remaining blood vessels will be additionally regressed using fine needle diathermy (on the day of transplantation). Afterwards, the incidence of graft rejection episodes will be evaluated for 24 months (primary endpoint). Overall graft survival, as well as regression of corneal vessels and/or recurrence, among other factors, will be analyzed (secondary endpoints). DISCUSSION: Based on preclinical and early pilot clinical evidence, we want to test the novel concept of temporary (lymph)angioregressive pretreatment of high-risk eyes by CXL to promote subsequent corneal graft survival. So far, there is no evidence-based approach to reliably improve graft survival in the high-risk corneal transplantation setting available in clinical routine. If successful, this approach will be the first to promote graft survival in high-risk transplants. It will significantly improve vision and quality of life in patients suffering from corneal blindness. TRIAL REGISTRATION: ClinicalTrials.gov NCT05870566. Registered on 22 May 2023.
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Trasplante de Córnea , Supervivencia de Injerto , Humanos , Estudios Prospectivos , Calidad de Vida , Rayos Ultravioleta/efectos adversos , Trasplante de Córnea/efectos adversos , Córnea/cirugía , Ceguera , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como AsuntoRESUMEN
PURPOSE: To analyze the relationship between storage time of split donor tissue and outcomes after deep anterior lamellar keratoplasty (DALK) and Descemet's membrane endothelial keratoplasty (DMEK). DESIGN: Retrospective analysis of a nonrandomized, consecutive, interventional case series. PARTICIPANTS: One hundred ten eyes with anterior stromal disease suitable for DALK and 110 eyes with endothelial disease suitable for DMEK underwent surgically successful split cornea transplantation combining both procedures within 7 days after splitting. METHODS: Split donor storage times (splitting to grafting) and total storage times (death to grafting) were correlated with the 1-year functional and morphologic outcomes after DALK and DMEK surgery using a Spearman correlation coefficient and a Mann-Whitney U test. MAIN OUTCOME MEASURES: Best spectacle-corrected visual acuity (BSCVA), endothelial cell density, and complication rates within 12 months of follow-up. RESULTS: The mean split donor storage time was 35 ± 47 hours (range, 0-162 hours) after splitting for anterior donor grafts and 21 ± 40 hours (range, 0-158 hours) for posterior grafts. The mean total storage time was 352 ± 108 hours (range, 108-678 hours) for anterior lamellas and 339 ± 109 hours (range, 96-630 hours) for posterior lamellas. One year after DALK, the mean BSCVA was 20/30 (range, 20/50-20/20), endothelial cell loss was 8% (range, 2%-16%), and the complication rate (Descemet's folds, epitheliopathy, loose sutures) was 18%. One year after DMEK, the mean BSCVA was 20/25 (range, 20/40-20/16), endothelial cell loss was 41% (range, 17%-63%), and the complication rate (partial graft detachment) was 62%. For DALK and DMEK, no significant association was observed between split donor storage time as well as total storage time and BSCVA (P ≥ 0.409), endothelial cell loss (P≥0.236), or complication rate (P ≥ 0.647) within 1 year of follow-up. CONCLUSIONS: Anterior and posterior donor tissue may be stored safely for up to 1 week in organ culture before use in DALK and DMEK surgery. This simplifies the clinical feasibility of split cornea transplantation to reduce donor shortage and cost in corneal transplantation in the future. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.