Early stage retina created from stem cells

IRVINE, Calif., June 1 (UPI) -- U.S. scientists say they have created an eight-layer, early stage retina from human embryonic stem cells.

The University of California-Irvine researchers said their accomplishment marks the first three-dimensional tissue structure to be made from stem cells. They said it also marks the first step toward the development of transplant-ready retinas to treat eye disorders such as retinitis pigmentosa and macular degeneration that affect millions.

"We made a complex structure consisting of many cell types," said Associate Professor Hans Keirstead, who led the study. "This is a major advance in our quest to treat retinal disease."

The Keirstead team said it utilized the differentiation technique to create the multiple cell types necessary for the retina. The greatest challenge, Keirstead said, was in the engineering. To mimic early stage retinal development, the researchers needed to build microscopic gradients for solutions in which to bathe the stem cells to initiate specific differentiation paths.

"Creating this complex tissue is a first for the stem cell field," Keirstead said. "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.

"What's so exciting with our discovery," Keirstead added, "is that creating transplantable retinas from stem cells could help millions of people, and we are well on the way."

The study appears in the Journal of Neuroscience Methods.