Neuronal stem/progenitor cells in the vertebrate eye

Abstract

We acquire information from the outside world through our eyes which contain the retina, the photosensitive component of the central nervous system. Once the adult mammalian retina is damaged, the retinal neuronal death causes a severe loss of visual function. It has been believed that the adult mammalian retina had no regenerative capacity. However, the identification of neuronal progenitor cells in the retina sheds some light on cellular therapies for damaged retinal regeneration. In this review, we highlight three potential stem/ progenitor cells in the eye, the ciliary body epithelium cells, the iris pigmented epithelium cells, and Müller glia. In order to make them prime candidates for the possible treatment of retinal diseases, it is important to understand their basic characters. In addition, we discuss the key signaling molecules that function extracellularly and determine whether neuronal progenitors remain quiescent, proliferate, or differentiate. Finally, we introduce a secreted protein, Tsukushi, which is a possible candidate as a niche molecule for retinal stem/progenitor cells.

JARID1B Protein Expression and Prognostic Implications in Uveal Melanoma

“…Interestingly, all 121 samples had positive JARID1B staining in the ciliary body epithelium. It has been suggested in the literature that progenitor cells do exist in the epithelium of the ciliary body, [49][50][51][52] which this study substantiates as JARID1B is thought to be a marker for stem/progenitor cells. 24 With regard to the recent study by Roesch et al that studied JARID1B expression in cutaneous melanoma, 24 study data did not support the hypothesis that JARID1B is an independent predictive factor for UM survival.…”

Neuropeptide Y system in the retina: From localization to function

“…Indeed, the transplantation of neural stem cells in patients with retinal degenerative diseases may help repopulating the damaged retina and/or rescue retinal neurons from future degeneration (Ahmad, 2001). Stem and progenitor cells have been localized in ciliary body epithelium (Cicero et al, 2009;Coles et al, 2004;MartinezNavarrete et al, 2008), iris pigment epithelium (Locker et al, 2009;MacNeil et al, 2007;Ohta et al, 2008) and peripheral retina (Bernardos et al, 2007;Das et al, 2006;Fausett and Goldman, 2006;Fischer and Reh, 2003;Jadhav et al, 2009;Locker et al, 2009;Ooto et al, 2004;Raymond et al, 2006). As previously discussed in this review, NPY is expressed in some of these areas, mainly in nerve fibers that innervate these stem cell niches (see Section 2.4).…”

“…The identification, characterization, and even transplantation of neural progenitor stem cells in the eye may open new opportunities for the treatment of several ocular diseases characterized by retinal cell death, such as retinitis pigmentosa, age-related macular degeneration, diabetic retinopathy and glaucoma (Ahmad, 2001;Bernardos et al, 2007;Ohta et al, 2008;Ooto et al, 2004;Tropepe et al, 2000). Indeed, the transplantation of neural stem cells in patients with retinal degenerative diseases may help repopulating the damaged retina and/or rescue retinal neurons from future degeneration (Ahmad, 2001).…”

Increased Müller Cell De-Differentiation After Grafting of Retinal Stem Cell in the Sub-Retinal Space of Royal College of Surgeons Rats

“…Recent studies have shown that they can also de-differentiated as endogenous retinal progenitor cells and show proliferative and regenerative potential under certain conditions in vitro and in vivo. [15][16][17]19,[22][23][24][25][26][27][28] Our previous study has shown that in the RCS rat model, these Mü ller cells can be activated and dedifferentiated into retinal progenitors. 29 Based on Mü ller cells' neuronal regeneration potential, we raised a hypothesis that Mü ller cell may play an important role in rSC transplantation.…”