Production and transplantation of retinal cells from human and mouse embryonic stem cells.

Over the last few years, numerous studies have introduced strategies for the generation of neuronal populations from embryonic stem cells. These techniques are valuable both in the study of early neurogenesis and in the generation of an unlimited source of donor cells for replacement therapies. We have developed a protocol to direct mouse and human embryonic stem cells to retinal fates by using the current model of eye specification. Our method is a multistep protocol in which the cultures are treated with IGF1 and a combination of BMP and Wnt inhibitors to promote the expression of key retinal progenitor genes, as assayed by RT-PCR and immunofluorescence microscopy. The retinal progenitor population spontaneously undergoes differentiation towards various types of retinal neurons, including photoreceptors.