In another world first in the fight against degenerative eye disorders, scientists from the Universtiy of California, Irvine, have created an eight-layer early-stage retina from human embryonic stem cells. Not only is this the world's first three-dimensional complex tissue structure to be made from stem cells, but it also marks the first step toward the development of transplant-ready retinas to treat eye disorders affecting millions.

The retina is the part of the eye that records images and sends them from the eye to the brain via the optic nerve. Building on a process designed in a previous study, researchers created multiple cell types using microscopic gradients for solutions in which to bathe the stem cells and initiate specific differentiation paths.

"Creating this complex tissue is a first for the stem cell field," said Hans Keirstead, study leader of the Reeve-Irvine Research Center and the Sue & Bill Gross Stem Cell Research Center at UCI. "Dr. Gabriel Nistor in our group addressed a really interesting scientific problem with an engineering solution, showing that gradients of solutions can create complex stem cell-based tissues. We made a complex structure consisting of many cell types. This is a major advance in our quest to treat retinal disease. What’s so exciting with our discovery is that creating transplantable retinas from stem cells could help millions of people, and we are well on the way.”

The UCI researchers are still testing the retinas in animal models and hope that if they significantly improve vision that they could proceed to human clinical trials.

In a previous study the scientists had designed and tested the differentiation technique. The results of this work has gone on to form the foundation for the world's first clinical trials using stem cell-based therapy for acute spinal injury.

China, rising star of regenerative medicine, has had some success in improving eye cataracts with stem cell-based therapy, and there have been advances in addressing blindness in one or both eyes with the use of contact lenses applied with healthy stem cells but this is the first to address retinal disorders with stem cell therapy.

More than 10 million people in the USA alone suffer from “macular degeneration,” which is the leading cause of blindness in people over fifty-five. Furthermore, 100,000 people suffer from retinitis pigmentosa, a progressive, genetic disorder, so the impact of such research could be a significant step in combating these degenerative disorders.

The study was published in the Journal of Neuroscience Methods and was the joint effort of Dr Gabriel Nistor, Magdalene J. Seiler, Fengrong Yan, David Ferguson, and was supported by The Lincy Foundation and private donations.