Ultrastructural and immunocytochemical analysis of the circumferential microfilament bundle in avian retinal pigmented epithelial cells in vitro

Retinal pigmented epithelial cells (PECs) of chicken embryos extensively and almost synchronously transdifferentiate into lens cells in medium containing phenylthiourea and testicular hyaluronidase, passing through the bipotent dedifferentiated state. We have isolated genes that are expressed specifically by either pigment or lens cells and analyzed their expression in the transdifferentiation process. The expression of some proto-oncogenes was also studied. In the dedifferentiation process, expression of the c-myc gene was enhanced and the transcription of PEC-specific genes (MMP115, pP344) was completely repressed. However, transcription of lens-specific genes (alpha-, beta- and delta-crystallins genes) remained silent in dedifferentiated pigment cells. Activation of len- or PEC-specific genes occurred only in conditions permissive for lens or PEC differentiation, respectively. These results indicated that lens transdifferentiation from PECs proceeds through a multipotent (or at least bipotent) intermediate cell state in which the c-myc gene is activated, but neither PEC- nor lens-specific genes are expressed.

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Characterization of an in vitro Model of Calcification in Retinal Pigmented Epithelial Cells

Journal of Atherosclerosis and Thrombosis ◽

10.5551/jat.10.48 ◽

2003 ◽

Vol 10 (1) ◽

pp. 48-56 ◽

Cited By ~ 13

Author(s):

Hideki Sugitani ◽

Hiroshi Wachi ◽

Hayato Murata ◽

Fumiaki Sato ◽

Robert P. Mecham ◽

...

Keyword(s):

Epithelial Cells ◽

Retinal Pigmented Epithelial Cells

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Quick freeze-deep etch analysis of microfilaments in the circumferential bundle of retinal pigmented epithelial cells M vitro

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142426 ◽

1986 ◽

Vol 44 ◽

pp. 160-161

Author(s):

Ryuji Kodama ◽

Goro Eguchi ◽

Robert O. Kelley

Keyword(s):

Epithelial Cells ◽

Cell Surface ◽

Embryonic Chick ◽

Rpe Cells ◽

Chick Retina ◽

Lens Cell ◽

Culture Environment ◽

Retinal Pigmented Epithelial Cells

Pigmented epithelial cells from embryonic chick retina can transdifferentiate in vitro to express either pigmented (RPE) or lens cell (LC) phenotypes in response to alterations in the external culture environment. These observations suggest that the dedifferentiated phenotype of RPE cells is, at least, bipotential and that expression of either of two differentiated phenotypes is mediated by the cell surface and the associated cytoskeleton.

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Effects of Vitamin D3 and Meso-Zeaxanthin on Human Retinal Pigmented Epithelial Cells in Three Integrated in vitro Paradigms of Age-Related Macular Degeneration

Frontiers in Pharmacology ◽

10.3389/fphar.2021.778165 ◽

2021 ◽

Vol 12 ◽

Author(s):

Francesca Lazzara ◽

Federica Conti ◽

Chiara Bianca Maria Platania ◽

Chiara M. Eandi ◽

Filippo Drago ◽

...

Keyword(s):

Oxidative Stress ◽

Epithelial Cells ◽

Macular Degeneration ◽

Vision Loss ◽

Cell Damage ◽

Retinal Disease ◽

Age Related Macular Degeneration ◽

Age Related ◽

Retinal Pigmented Epithelial Cells

Age-related macular degeneration (AMD) is a degenerative retinal disease and one of major causes of irreversible vision loss. AMD has been linked to several pathological factors, such as oxidative stress and inflammation. Moreover, Aβ (1–42) oligomers have been found in drusen, the extracellular deposits that accumulate beneath the retinal pigmented epithelium in AMD patients. Hereby, we investigated the hypothesis that treatment with 1,25(OH) 2D3 (vitamin D3) and meso-zeaxathin, physiologically present in the eye, would counteract the toxic effects of three different insults on immortalized human retinal pigmented epithelial cells (ARPE-19). Specifically, ARPE-19 cells have been challenged with Aβ (1–42) oligomers, H2O2, LPS, and TNF-α, respectively. In the present study, we demonstrated that the combination of 1,25(OH)2D3 and meso-zeaxanthin significantly counteracted the cell damage induced by the three insults, at least in these in vitro integrated paradigms of AMD. These results suggest that combination of 1,25(OH)2D3 and meso-zeaxathin could be a useful approach to contrast pathological features of AMD, such as retinal inflammation and oxidative stress.

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