Your replacement retinas might look like this

For people going blind from retinal degeneration, there are almost no therapies. Their vision dims and they lose their sight as doctors look on helplessly. But a new experiment involving retinas grown from stem cells promises a new direction for research — and, in the future, a possible treatment.

Photo of retinal neurons by Anai Gonzalez-Cordero

Scientists in the UK have grown new retinas for blind mice from stem cells. The best news is that when the researchers implanted the new retinal tissue, its cells formed connections with the rodents' already-existing neurons. It's not yet clear whether the retinas actually improved the animals' sight, but this is a promising first step.

Over at Technology Review, Susan Young explains:

The researchers used a new method for growing embryonic stem cells that enables them to turn into immature eye cells and self-organize into three-dimensional structures similar to those seen in a developing retina. Immature light-detecting cells were harvested from this culture and transplanted into the retinas of night-blind mice. There, the cells integrated with the natural cells of the eye and formed synaptic connections. The work did not involve testing how well the mice could see after the cells were implanted.

Read more at Technology Review.