During development, light-sensitive tissue lining the back of the eye, called the retina, forms from a structure known as the optic cup. In the new study, this structure spontaneously emerged from human embryonic stem cells (hESCs)--cells derived from human embryos that arc capable of developing into a variety of tissues--thanks to the cell culture methods optimized by Sasai and his team.
The hESC-derived cells formed the correct 3D shape and the two layers of the optic cup, including a layer containing a large number of light-responsive cells called photoreceptors.
Masayo Takahashi, an ophthalmologist on Sasai's team, has already started transferring sheets of retina from lab-grown optic cups into blind mice in hopes of restoring their vision, and she plans to do the same with monkeys by the year end.
Meanwhile, Yoshiki Sasai and colleagues at the RIKEN Centre for Developmental Biology in Kobe , reported that they had managed to induce human stem cells called "retinal precursor cells" to develop into a central component of the human eye called an optic cup.