New Scientist: A procedure involving transplanted stem cells may one day restore sight to the blind. Robin Ali of University College London and colleagues have grown retinal photoreceptor cells from mouse embryonic stem cells in a three-dimensional jelly culture. While the developing cells were still immature, the researchers transplanted them into the eyes of blind mice. There, the cells continued to mature and successfully connected with nerves that transmit visual signals to the brain. Although not enough cells were implanted to restore the mice’s vision, the procedure was successful enough to persuade the researchers that it’s just a matter of figuring out the number of cells needed and the optimum moment in their developmental stage to transplant them.