Retinal repair using ESC-derived cone photoreceptor precursors. (360G-Wellcome-096627_Z_11_A)

Retinal degenerations leading to loss of photoreceptors are a major cause of untreatable blindness; in particular theloss of cone photoreceptors reduces visual acuity in patients. The Ali laboratory has previously demonstrated proof of principle for cone photoreceptor transplantation into the adult wildtype and degenerate retina. They have shown that cone photoreceptor transplantation is feasible provided the donor cell population are correctly staged post-mitotic coneprecursors, isolated at the peak of cone genesis. As far fewer cones are present in the murine retina compared to rod photoreceptors, a more appropriate strategy to generate cone photoreceptors for transplantation is the use of mouse ES cells. The recent publication of a 3D retinal differentiation protocol closely mimicking the developing neural retina not only provides a model system with which to test the specification of photoreceptors towards a cone cell fate, but also enables the generation of large numbers of photoreceptors for transplantation studies. We hypothesise, that detailed investigation of the developmental signals leading to the acquisition of cone photoreceptor cell fate will lead to improved generation of stem cell-derived cones. This cell population will present a potential to be transplanted to the degenerate retina in order to restore cone-mediated visual responses.