Project description:Inherited retinal diseases and aged related macular degeneration are main causes of blindness that involves irreversible photoreceptor loss. Gene therapy approaches do not prevent photoreceptor degeneration during disease progression, and to date protocols for generating photoreceptors from pluripotent stem cells do not exist. Therefore, transplantation of photoreceptors containing retinal organoids is considered a potential option. However, in vitro formation of organoids requires animal-derived materials and they vary considerably in cell composition between batches, which strongly limits their applications in therapy. Here, we show that human recombinant retina-specific laminin isoform LN523, normally present in the extra cellular matrix ECM surrounding photoreceptors, supports differentiation of pluripotent embryonic stem cells to photoreceptor progenitors in vitro. Using a rabbit macular degeneration model, the transplanted and engrafted cells mature in vivo and form synaptic connectivity with the host retina. Furthermore, addition of a rod-derived cone viability factor increased the formation of cone photoreceptors. These results may pave the way for cell therapy treatment of macular degeneration.
Project description:Inherited retinal diseases and aged related macular degeneration are main causes of blindness that involves irreversible photoreceptor loss. Gene therapy approaches do not prevent photoreceptor degeneration during disease progression, and to date protocols for generating photoreceptors from pluripotent stem cells do not exist. Therefore, transplantation of photoreceptors containing retinal organoids is considered a potential option. However, in vitro formation of organoids requires animal-derived materials and they vary considerably in cell composition between batches, which strongly limits their applications in therapy. Here, we show that human recombinant retina-specific laminin isoform LN523, normally present in the extra cellular matrix ECM surrounding photoreceptors, supports differentiation of pluripotent embryonic stem cells to photoreceptor progenitors in vitro. Using a rabbit macular degeneration model, the transplanted and engrafted cells mature in vivo and form synaptic connectivity with the host retina. Furthermore, addition of a rod-derived cone viability factor increased the formation of cone photoreceptors. These results may pave the way for cell therapy treatment of macular degeneration.
Project description:Illumina Infinium HumanMethylation450 BeadChip data from genomic DNA of retinal pigment epithelium from Age-related Macular Degeneration patients or age-matched controls.
Project description:To explore whether IL-4 could exert a novel protective role for RPE damage and attenuate the pathogenesis of dry age-related macular degeneration (AMD), we established a retinal degeneration model of dry AMD by intravenous injection of NaIO3, and explored the treatment effects of intravitreal IL-4 injection. We found exogenous IL-4 protected against retinal degeneration characterized by well-preserved structures and improved retinal function. The RNA-seq analysis revealed that IL-4 treatment suppressed the essential oxidative and pro-inflammatory pathways in the degenerative retina. IL-4 induced the expression of IL-4Rα and Nrf2 for anti-oxidative defense in vivo and in vitro. Our data provides evidences that IL-4 can be a useful neuroprotective agent against retinal degeneration due to its antioxidant and anti-inflammatory property through Nrf2 activation. The IL-4/IL-4Rα-Nrf2 axis maybe the potential targets for the development of novel therapies for dry AMD.
Project description:The retinal pigment epithelium (RPE) provides vital support to photoreceptor cells and its dysfunction is associated with the onset and progression of age-related macular degeneration (AMD). Surgical provision of RPE cells may ameliorate AMD and thus it would be valuable to develop sources of patient-matched RPE cells for this application of regenerative medicine. We describe here the generation of functional RPE-like cells from fibroblasts that represent an important step toward that goal. We identified candidate master transcriptional regulators of RPEs using a novel computational method and then used these regulators to guide exploration of the transcriptional regulatory circuitry of RPE cells and to reprogram human fibroblasts into RPE-like cells. The RPE-like cells share key features with RPEs derived from healthy individuals, including morphology, gene expression and function, and thus represent a step toward the goal of generating patient-matched RPE cells for treatment of macular degeneration. Expression analysis was performed on induced retinal pigment epithelium-like cells.
Project description:We discuss the use of pluripotent stem cell lines carrying fluorescent reporters driven by retinal promoters to derive three-dimensional (3-D) retina in culture and how this system can be exploited for elucidating human retinal biology, creating disease models in a dish, and designing targeted drug screens for retinal and macular degeneration. Furthermore, we realize that stem cell investigations are labor-intensive and require extensive resources. To expedite scientific discovery by sharing of resources and to avoid duplication of efforts, we propose the formation of a Retinal Stem Cell Consortium. In the field of vision, such collaborative approaches have been enormously successful in elucidating genetic susceptibility associated with age-related macular degeneration.
Project description:Age-related macular degeneration (AMD), featured with dysfunction and loss of retinal pigment epithelium (RPE), is lacking efficient therapeutic approaches. According to our previous studies, human amniotic epithelial stem cells (hAESCs) may serve as a potential seed cell source of RPE cells for therapy because they have no ethical concerns, no tumorigenicity, and little immunogenicity. Herein, trichostatin A and nicotinamide can direct hAESCs differentiation into RPE like cells. The differentiated cells display the morphology, marker expression and cellular function of the native RPE cells, and noticeably express little MHC class II antigens and high level of HLA-G. Importantly, visual function and retinal structure of Royal College of Surgeon (RCS) rats, a classical animal model of retinal degeneration, were rescued after subretinal transplantation with the hAESCs-derived RPE like cells. We established a high-efficient, low-cost and safety-guaranteed system for generating functional RPE cells from hAESCs. These results suggest a novel and ideal therapeutic strategy for retinal degeneration diseases
Project description:Dogs are commonly used models of human inherited retinal disorders. Because the dog retina contains a macula-like region, dogs are susceptible to maculopathies with many shared genetic etiologies with humans. Human macular gene expression has been characterized and provides insight into the underlying basis of macular disease. We sought to compare macular gene expression profiles in dogs and humans and interrogate macular disease-associated genes for differential expression between macula and periphery. RNA sequencing was performed on 8mm samples of the dog macular region and superior peripheral region, sampling retina and retinal pigmented epithelium/choroid separately. Read sequences were mapped to CanFam3.1 and raw read counts were analyzed to determine significantly differentially expressed genes between macula and periphery within each tissue. A similar analytic pipeline was used with a published dataset of human samples to allow direct dog/human comparisons. Pathways and processes involved in significantly DEGs were identified using the Database for Annotation, Visualization and Integrated Discovery. Dogs and humans shared the extent and direction of macular retinal differential gene expression, with multiple shared biological pathways implicated in differential expression. There were fewer similarities between dog and human in the supporting tissues of the retina (the RPE, choroid, sclera). Many genes implicated in heritable retinal and macular disorders in both dogs and humans were differentially expressed between macula and periphery. Approximately 2/3 of genes associated with human age-related macular degeneration were differentially expressed in at least one human tissue, whereas approximately half were differentially expressed in at least one dog tissue. This work underpins the dog macular retinal region as analogous to the human macula in terms of differential gene expression. Whilst age-related maculopathy has not been described in dogs, evidence supports the study of aging of the macula and susceptibility to age-associated pathology in dogs.
Project description:Dysfunctional humoral and cellular innate immunity are key components in the development and progression of age-related macular degeneration (AMD). Specifically, chronically activated microglia and their disturbed regulatory system contribute to retinal degeneration. Galectin-3, a b-galactose binding protein, is a potent driver of macrophage and microglia activation and has been implicated in neuroinflammation, including neurodegenerative diseases of the brain. Here, we report that galectin-3 is strongly upregulated in reactive retinal microglia of AMD patients and in two related mouse models of retinal degeneration. Specific targeting of galectin-3 by genetic knockout or using the small-molecule inhibitor TD139 blocks microglia reactivity and protects from retinal damage in different models of light-induced retinal degeneration. These data define galectin-3 as potent driver of retinal degeneration and highlight the protein as a drug target for ocular immunomodulatory therapies.