Abstract
Regeneration and plasticity refer to the ability of certain progenitor cells to produce cell lineages with specific morphological and functional settings. The pathway from a less delineated or immature phenotype to a mature or specialized one follows intricate routes where a monumental array of molecular elements, basically transcription factors and epigenetic regulators that turn off or on a specific phenotypic change, play a fundamental role. Nature itself offers procedures to healing strategies. Therapy approaches to pathologies in the realm of ophthalmology may benefit from the knowledge of the properties and mechanisms of activation of different routes controlling the pathways of cell definition and differentiation. Specification of cell identity, not only in terms of phenotypic traits, but also regarding the mechanisms of gene expression and epigenetic regulation, will provide new tools to manipulating cell fates and status, both forward and backwards. In the human eye, two main locations shelter stem cells: the limbus, which is situated in the limit of the cornea and the conjuctiva, and the ciliary body pars plana. Transplantation of limbal cells is currently used in certain pathologies where corneal epithelium is damaged. Therapeutic applications of retina progenitors are not yet fully developed due to the complexity of the cellular components of the multilayer retinal architecture. Animal models of Retinitis pigmentosa or Glaucoma offer an interesting approach to validate certain techniques, such as the direct injection of progenitors into the vitreal compartment, aimed to restoring retinal function.
Keywords: Ciliary body, limbus, plasticity, photoreceptors, regeneration, retinal ganglion cells, retina, stem cell, Neuroprotection, ophthalmology, cornea, conjuctiva, pars plana, Retinitis, Glaucoma, photoreceptors,, regeneration,, retinal ganglion cells,, retina,, oocyte, totipotent cell, trophoblast., Embryonic stem, postnatal stem cells, sclera,, keratocytes, Bowman membrane, stroma, Descemet membrane, Collagen fibres, Descemet´s stripping endothelial keratoplasty (DSEK), homeostasis, transient amplifying cells (TAC),, oligopotent stem cells, corneal epithelium, amniotic membranes, fibrin, fibroin, microenvironment, allogenic transplant, osteoblasts, adipocytes, fibroblasts, vascularisation, adipose-derived stem cells, osteo-odonto keratoprothesis, pluripotent stem (iPS), regenerative therapy., transcription factor, epigenetic mechanisms, retinal ganglion cells (RGCs), amacrine cells, amphibians, neurons, embryonic retinal cell, Embryonic Stem), rod genesis., fluorescence activated cell sorting, green fluo-rescent protein, oncogenesis, basic fibroblast growth factor, -aminoadipic acid, Müller cell processes, neural retina
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