Scaffolding, Stem Cells Could Save Sight

Researchers trying to restore vision damaged by disease have found promise in a tiny implant that sows the seeds of new cells.

The device is the brainchild of Gary Wnek, PhD, a Case Western Reserve University macromolecular scientist and engineer, and his research partners from Harvard University and the University of California at Irvine. Wnek believes this new implant could treat eye diseases like retinitis pigmentosa and age-related macular degeneration.

These diseases lay waste to the retina, the layer at the back of the eye that contains light-sensitive cells, or photoreceptors, which can't regenerate. Scientists previously tried to use stem cells to promote cell growth to treat these diseases, but scar tissue on the diseased retinas crippled the new cells' ability to take root.

Wnek says his implant clears the scar tissue, delivers the retinal stem cells and provides scaffolding on which new cells grow.

As reported in the January issue of Biomaterials, the scaffolding is made of a material similar to biodegradable sutures, and tiny pockets in the mesh of the scaffolds are filled with an enzyme that breaks down scar tissue.

In preliminary tests, the device cleared scar tissue within five days with no apparent ill effects on the retinal stem cells. "It's the first step in a very long process," Wnek says of these laboratory results. But for millions of people worldwide who suffer from debilitating sight loss, it's a step in the right direction.