Stem cells coaxed into forming partial eyeball
Mouse stem cells have been coaxed into forming a partial eyeball, and the method may one day lead to retina transplants.
Yoshiki Sasai at the RIKEN Center for Developmental Biology in Kobe, Japan, and colleagues encouraged embryonic stem cells to develop into retinal cells, and then grew them alongside a protein matrix to promote the formation of tissue.
Over 12 days, the retinal cells formed a vesicle which subsequently transformed into a cup-like structure. Within this "optic cup", six major types of retinal cells were identified. They had spontaneously arranged themselves into six different layers, mimicking those seen in the adult retina.
While it is not yet possible to generate a fully formed eye – including a lens, sclera and cornea – Sasai says it may be feasible to use human stem cells with minor modifications to generate retinal tissues large enough for human transplantation in the next few years.
"The retina is severely impaired in genetic diseases such as retinitis pigmentosa. This replacement therapy would become practical once human retina tissue is available by our method," says Sasai.