Human embryonic stem cell-derived retinal pigment epithelium in patients with age-related macular degeneration and Stargardt's macular dystrophy: follow-up of two open-label phase 1/2 studies

Purpose Ghost drusen (GD) are pyramidal or dome-shaped retinal pigment epithelium elevations observed in some geographic atrophy (GA) areas in the context of age-related macular degeneration (AMD). The purpose was to investigate the first morphologic features preceding GD on spectral-domain optical coherence tomography (SD-OCT) on patients with GA associated with AMD. Methods A retrospective observational study was performed on a series of patients with GA that had at least 3 years of follow-up. Using the follow-up tool of SD-OCT, we tracked the initial lesions that could lead to GD. Results Among 442 patients with GA, 37 had well defined GD (8%). We included the 17/37 patients (31 eyes) with at least 3 years of follow-up for analysis, which led to a total of 582 counted GD. Most GD were already present at the first visit, and remained stable. However, on 13 of the 582 analyzed GD (2.2%), soft drusen were shown as the initial lesion, which progressively turned into GD. Conclusions GD were observed in less than 10% of eyes with GA. None of the ghost drusen turned into another shaped lesion, suggesting that GD is a possible final stage of evolution. In a few cases, large drusen were shown as the primary lesion that progressed into GD.

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Embryonic stem cell microenvironment enhances proliferation of human retinal pigment epithelium cells by activating the PI3K signaling pathway

Stem Cell Research & Therapy ◽

10.1186/s13287-020-01923-0 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Jiahui Liu ◽

Liu Yang ◽

Xiaoran Wang ◽

Shoubi Wang ◽

Zheqian Huang ◽

...

Keyword(s):

Gene Expression ◽

Stem Cell ◽

Signaling Pathway ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Embryonic Stem ◽

Age Related Macular Degeneration ◽

Pi3k Signaling ◽

Age Related ◽

Pi3k Signaling Pathway

Abstract Background Retinal pigment epithelium (RPE) replacement has been proposed as an efficacious treatment for age-related macular degeneration (AMD), which is the primary cause of vision loss in the elderly worldwide. The embryonic stem cell (ESC) microenvironment has been demonstrated to enable mature cells to gain a powerful proliferative ability and even enhance the stem/progenitor phenotype via activation of the phosphoinositide 3-kinase (PI3K) signaling pathway. As the PI3K signaling pathway plays a pivotal role in proliferation and homeostasis of RPE, we hypothesize that the stemness and proliferative capability of RPE can be enhanced by the ESC microenvironment via activation of the PI3K signaling pathway. Methods To investigate whether the ESC microenvironment improves the stem cell phenotype and proliferation properties of human RPE (hRPE) cells by regulating the PI3K signaling pathway, primary hRPE cells were cocultured with either ESCs or human corneal epithelial cells (CECs) for 72 h, after which their proliferation, apoptosis, cell cycle progression, and colony formation were assayed to evaluate changes in their biological characteristics. Gene expression was detected by real-time PCR and protein levels were determined by western blotting or immunofluorescence. LY294002, an antagonist of the PI3K signaling pathway, was used to further confirm the mechanism involved. Results In comparison to hRPE cells cultured alone, hRPE cells cocultured with ESCs had an increased proliferative capacity, reduced apoptotic rate, and higher colony-forming efficiency. The expression of the stem cell-associated marker KLF4 and the differentiation marker CRALBP increased and decreased, respectively, in hRPE cells isolated from the ESC coculture. Furthermore, PI3K pathway-related genes were significantly upregulated in hRPE cells after exposure to ESCs. LY294002 reversed the pro-proliferative effect of ESCs on hRPE cells. In contrast, CECs did not share the ability of ESCs to influence the biological behavior and gene expression of hRPE cells. Conclusions Our findings indicate that the ESC microenvironment enhances stemness and proliferation of hRPE cells, partially via activation of the PI3K signaling pathway. This study may have a significant impact and clinical implication on cell therapy in regenerative medicine, specifically for age-related macular degeneration.

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Autologous retinal pigment epithelium and choroid translocation in patients with exudative age-related macular degeneration: short-term follow-up

American Journal of Ophthalmology ◽

10.1016/s0002-9394(03)00384-2 ◽

2003 ◽

Vol 136 (4) ◽

pp. 688-695 ◽

Cited By ~ 95

Author(s):

Jan C van Meurs ◽

Pieter R Van Den Biesen

Keyword(s):

Retinal Pigment Epithelium ◽

Macular Degeneration ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Age Related Macular Degeneration ◽

Short Term ◽

Age Related

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Comparative Safety of Bevacizumab, Ranibizumab, and Aflibercept for Treatment of Neovascular Age-Related Macular Degeneration (AMD): A Systematic Review and Network Meta-Analysis of Direct Comparative Studies

Journal of Clinical Medicine ◽

10.3390/jcm9051522 ◽

2020 ◽

Vol 9 (5) ◽

pp. 1522 ◽

Cited By ~ 1

Author(s):

Anna A. Plyukhova ◽

Maria V. Budzinskaya ◽

Kirill M. Starostin ◽

Robert Rejdak ◽

Claudio Bucolo ◽

...

Keyword(s):

Systematic Review ◽

Adverse Events ◽

Macular Degeneration ◽

Pigment Epithelium ◽

Meta Analysis ◽

Retinal Pigment ◽

Age Related Macular Degeneration ◽

Macular Atrophy ◽

Age Related

Background: Since the efficacy of ranibizumab (RBZ), bevacizumab (BVZ) and aflibercept (AFB) is comparable in neovascular age-related macular degeneration (AMD), we conducted a systematic review and meta-analysis to evaluate the long-term safety profiles of these agents, including ocular safety. Methods: Systematic review identifying randomized controlled trials (RCTs) comparing RBZ, BVZ and AFB directly published before March 2019. Serious ocular adverse events (SOAE) of special interest were endophthalmitis, pseudo-endophthalmitis, retinal pigment epithelium tear and newly identified macular atrophy. Results: Thirteen RCTs selected for meta-analysis (4952 patients, 8723 people-years follow-up): 10 compared RBZ vs. BVZ and three RBZ vs. AFB. There were no significant differences in almost all adverse events (systemic and ocular) between BVZ, RBZ and AFB in up to two years’ follow-up. Macular atrophy was reported heterogeneously and not reported as SOAE in most trials. Conclusions: Direct comparison of RBZ, BVZ and AFB safety profiles in the RCT network meta-analytical setting have not revealed a consistent benefit of these three commonly used anti-vascular endothelial growth factor (anti-VEGF) agents in AMD. Network model ranking highlighted potential benefits of RBZ in terms of a systemic safety profile; however, this appears a hypothesis rather than a conclusion. Newly identified macular atrophy is underestimated in RCTs—future real-world data should be focused on SOAE.

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Development-related mitochondrial properties of retinal pigment epithelium cells derived from hEROs

International Journal of Ophthalmology ◽

10.18240/ijo.2021.08.02 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1138-1150

Author(s):

Hao-Jue Xu ◽

◽

Ting Zou ◽

Zheng-Qin Yin ◽

◽

...

Keyword(s):

Flow Cytometry ◽

Retinal Pigment Epithelium ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Embryonic Stem ◽

Age Related Macular Degeneration ◽

Level Energy ◽

Rpe Cells ◽

Age Related ◽

High Level

AIM: To explore the temporal mitochondrial characteristics of retinal pigment epithelium (RPE) cells obtained from human embryonic stem cells (hESC)-derived retinal organoids (hEROs-RPE), to verify the optimal period for using hEROs-RPE as donor cells from the aspect of mitochondria and to optimize RPE cell-based therapeutic strategies for age-related macular degeneration (AMD). METHODS: RPE cells were obtained from hEROs and from spontaneous differentiation (SD-RPE). The mitochondrial characteristics were analyzed every 20d from day 60 to 160. Mitochondrial quantity was measured by MitoTracker Green staining. Transmission electron microscopy (TEM) was adopted to assess the morphological features of the mitochondria, including their distribution, length, and cristae. Mitochondrial membrane potentials (MMPs) were determined by JC-1 staining and evaluated by flow cytometry, reactive oxygen species (ROS) levels were evaluated by flow cytometry, and adenosine triphosphate (ATP) levels were measured by a luminometer. Differences between two groups were analyzed by the independent-samples t-test, and comparisons among multiple groups were made using one-way ANOVA or Kruskal-Wallis H test when equal variance was not assumed. RESULTS: hEROs-RPE and SD-RPE cells from day 60 to 160 were successfully differentiated from hESCs and expressed RPE markers (Pax6, MITF, Bestrophin-1, RPE65, Cralbp). RPE features, including a cobblestone-like morphology with tight junctions (ZO-1), pigments and microvilli, were also observed in both hEROs-RPE and SD-RPE cells. The mitochondrial quantities of hEROs-RPE and SD-RPE cells both peaked at day 80. However, the cristae of hEROs-RPE mitochondria were less mature and abundant than those of SD-RPE mitochondria at day 80, with hEROs-RPE mitochondria becoming mature at day 100. Both hEROs-RPE and SD-RPE cells showed low ROS levels from day 100 to 140 and maintained a normal MMP during this period. However, hEROs-RPE mitochondria maintained a longer time to produce high levels of ATP (from day 120 to 140) than SD-RPE cells (only day 120). CONCLUSION: hEROs-RPE mitochondria develop more slowly and maintain a longer time to supply high-level energy than SD-RPE mitochondria. From the mitochondrial perspective, hEROs-RPE cells from day 100 to 140 are an optimal cell source for treating AMD.

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Investigation of Differentiated Embryonic Stem Cells Growth on Optimized Porous Polymeric Bed with Fuzzy System

Journal of Shahid Sadoughi University of Medical Sciences ◽

10.18502/ssu.v29i9.7911 ◽

2021 ◽

Author(s):

Saleheh Shahmoradi ◽

Fatemeh Yazdian ◽

Amin Janghorbani ◽

Leila Satarian ◽

Farnaz Behroozi ◽

...

Keyword(s):

Stem Cells ◽

Embryonic Stem Cells ◽

Retinal Pigment Epithelium ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Embryonic Stem ◽

Age Related Macular Degeneration ◽

Age Related ◽

Retinal Pigment Epithelium Cells ◽

Epithelium Cells

Introduction: Age-related macular degeneration (AMD) is one of the retina diseases in which retinal pigment epithelium cells are degraded and lead to blindness. Available treatments only slow down the progression of it. In this study, human embryonic stem cells (hESCs) differentiated into retinal pigment epithelium cells were cultured on a polycaprolactone scaffold. Methods: The optimization of the diameter of the produced scaffolds by electrospinning method was done using the fuzzy method for the first time. To improve cell adhesion and proliferation, related parameters to alkaline hydrolysis method were optimized and hydrophobic surface of scaffold was modified. After in vitro analysis, cells were cultured on different groups of scaffolds. In vivo analyses were done and cells culture on scaffolds observed. Results: The optimal parameters for the scaffold based on the fuzzy model were 18.1 kV for voltage, 0.07 g / ml for solution concentration and 115 nm for scaffold diameter, respectively. The immersion time of the scaffold in alkaline solution and concentration of solution were measured 97 min and 3.7 M, respectively. The treated scaffold had a higher degradation rate and water adsorption. MTT-Assay results showed that scaffolds with modified surfaces had a higher amount of cell viability and proliferation after 7 days. SEM image results confirmed this finding after almost two months. Additionally, the results of ICC test showed that after passing this time, cells kept their RPE and epithelium. Conclusion: Based on the results, the hydrolyzed scaffold is a suitable substrate for cell proliferation and can be a good option for AMD treatment.

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OCT Biomarkers in Neovascular Age-Related Macular Degeneration: A Narrative Review

Journal of Ophthalmology ◽

10.1155/2021/9994098 ◽

2021 ◽

Vol 2021 ◽

pp. 1-16

Author(s):

Cristian Metrangolo ◽

Simone Donati ◽

Marco Mazzola ◽

Liviana Fontanel ◽

Walter Messina ◽

...

Keyword(s):

Macular Degeneration ◽

Treatment Response ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Subretinal Fluid ◽

Age Related Macular Degeneration ◽

Initial Assessment ◽

Clinical Approach ◽

Age Related

Age-related macular degeneration (AMD) is the leading cause of legal blindness in elderly people. Neovascular AMD (nAMD) is responsible for the majority of cases of severe visual loss in eyes with AMD. Optical coherence tomography (OCT) is the most widely used technology for the diagnosis and follow-up of nAMD patients, which is widely used to study and guide the clinical approach, as well as to predict and evaluate treatment response. The aim of this review is to describe and analyze various structural OCT-based biomarkers, which have practical value during both initial assessment and treatment follow-up of nAMD patients. While central retinal thickness has been the most common and one of the first OCT identified biomarkers, today, other qualitative and quantitative biomarkers provide novel insight into disease activity and offer superior prognostic value and better guidance for tailored therapeutic management. The key importance of retinal fluid compartmentalization (intraretinal fluid, subretinal fluid, and subretinal pigment epithelium (RPE) fluid) will be discussed firstly. In the second part, the structural alterations of different retinal layers in various stages of the disease (photoreceptors layer integrity, hyperreflective dots, outer retinal tubulations, subretinal hyperreflective material, and retinal pigment epithelial tears) will be analyzed in detail. The last part of the review will focus on how alterations of the vitreoretinal interface (vitreomacular adhesion and traction) and of the choroid (sub-RPE hyperreflective columns, prechoroidal clefts, choroidal caverns, choroidal thickness and choroidal volume, and choroidal vascular index) interact with nAMD progression. OCT technology is evolving very quickly, and new retinal biomarkers are continuously described. This up-to-date review article provides a comprehensive description on how structural OCT-based biomarkers provide a valuable tool to monitor the progression of the disease and the treatment response in nAMD patients. Thus, in this perspective, clinicians will be able to allocate hospital resources in the best possible way and tailor treatment to the individual patient’s needs.

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