Scientists at UC Irvine say they’ve created an early-stage retina from human embryonic stem cells — a feat that could lead to made-to-order retinas for transplant into patients with eye disorders.
The retina, composed of eight layers of cells, also is the first piece of complex tissue grown from stem cells — that is, more than one cell-layer deep, with multiple cell types working together — said Hans Keirstead of the Reeve-Irvine Research Center and UCI’s Sue and Bill Gross Stem Cell Research Center.
“This is a tremendous advance in the retinal field, in that it provides the first step toward a renewable source of tissue for transplantation,” Keirstead said Wednesday. “That’s novel. There is no such thing in the world right now. So it’s a real breakthrough.”
In the $1.5 million, three-year study that produced the retina, Keirstead and his team relied on experience during work last year on spinal cord injury: prodding human embryonic stem cells to grow into different cell types.
Then the scientists bathed the variety of retinal cells that resulted in a series of solutions containing growth factors and hormones. That process, the work Gabriel Nistor of Keirstead’s research group, switched on early-stage development of the cells and got them to form complex tissue.
Keirstead said they are now testing early-stage retinas in animals to find out if they improve vision. If they do, the next step would be human clinical trials.
The retina, at the back of the eye, registers the images we see and sends them to the brain through the optic nerve.
Growing retinas from stem cells could help more than 10 million Americans who suffer from macular degeneration, a leading cause of blindness.
It could also be used to treat about 100,000 in America who have retinitis pigmentosa, a progressive, genetic disorder that also leads to blindness.
Embryonic stem cells are exciting to researchers because they have the potential to become many different kinds of cells in the human body. Not only spinal cord injuries, but Parkinson’s disease and a variety of other conditions could one day be treated using stem cells.
Such research causes controversy when stem cells are derived from human embryos, even those destined to be discarded — for example, excess embryos stored in fertility clinics.
Keirstead and his team used such cells after getting consent from the parents.
Other researchers, however, including some at UCI, are working to create stem cells from a patient’s own, adult cells, bypassing the need to use embryos.
The new study was published this month online in the Journal of Neuroscience Methods.
