PURPOSE Retinal pigmented epithelial (RPE) cells may contribute to retinal immune privilege. Daily phagocytosis and degradation of photoreceptor cell outer segment tips by RPE provide substantial amounts of retinal autoantigens for potential MHC occupancy. RPE are well placed to modulate antigen (Ag)-specific activation of T cells in the outer retina under conditions in which inflammatory media...

Retinal and choroidal inflammatory lesions are important causes of visual loss, but the mechanisms regulating intraocular inflammation remain poorly understood. By virtue of its position at the blood-retina barrier, the retinal pigment epithelium (RPE) cells may be critical to the initiation and propagation of ocular inflammation. Previously we showed that cytokine-stimulated RPE cells produce ...

The cytoskeleton of normal and reactive retinal pigment epithelium (RPE) was analyzed immunohistochemically in five light microscopically normal formalin-fixed, paraffin-embedded human eyes enucleated because of orbital tumor and in 44 eyes with a uveal melanoma. In 26 eyes, the RPE overlying the tumor was morphologically normal or atrophic; in 18 eyes, hyperplastic changes were present. Normal...

PURPOSE Retinal pigmented epithelium derived from human induced pluripotent stem (iPS) cells (iPS-RPE) may be a source of cells for transplantation. For this reason, it is essential to determine the functional competence of iPS-RPE. One key role of the RPE is uptake and processing of retinoids via the visual cycle. The purpose of this study is to investigate the expression of visual cycle prote...

Compared with many induced pluripotent stem cell (iPSC) lines generated using retrovirus and other non-integrating methods, the utilization of human protein-induced iPSC (piPSC) lines may provide a safer alternative for the generation of retinal pigment epithelial (RPE) cells for transplantation in retinal degenerative diseases. Here we assess the ability of piPSCs to differentiate into RPE cel...

Optical measurements of the pigments of the retinal pigment epithelium (RPE) and choroid were made on 38 human autopsy eyes of both blacks and whites, varying in age between 2 wk and 90 yr old. Lipofuscin in melanin-bleached RPE was measured as fluorescence at 470 mm following excitation at 365 nm and was found to be proportional to fluorescence measured at 560 nm in unbleached tissue. Transmis...

PURPOSE The purpose of this study was to identify the molecular basis of the apical membrane K(+) conductance in native bovine retinal pigment epithelium (RPE). METHODS RT-PCR, Northern blot, and Western blot analyses were used to detect the expression of the inwardly rectifying K(+) (Kir) channel subunits Kir7.1 and Kir4.1 in native bovine RPE and neural retina. The distribution of Kir7.1 pr...

Retinal pigment epithelial (RPE) cells have crucial roles in the initiation and development of human ophthalmic diseases. Our previous study suggested that transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1) is a potential target in the progression and pathogenesis of human proliferative vitreoretinopathy disease. The present study further analyzed the role of TAK1 inhibitor, LYTAK1,...

The retinal pigment epithelium (RPE) shares its developmental origin with the neural retina (NR). When RPE development is disrupted, cells in the presumptive RPE region abnormally differentiate into NR-like cells. Therefore, the prevention of NR differentiation in the presumptive RPE area seems to be essential for regionalizing the RPE during eye development. However, its molecular mechanisms a...

We compared aged adult and fetal retinal pigment epithelium (RPE) migration and proliferation in cell culture. Aged adult RPE resurfaced on dishes coated with human or mouse laminin, human or rat collagen I, human or mouse collagen IV, or human fibronectin. Resurfacing was best on bovine corneal endothelial cell extracellular matrix. Resurfacing was worst on mouse laminin. Fetal RPE resurfacing...