The findings were presented at Neuroscience 2009, the annual meeting of the Society for Neuroscience and the world's largest source of emerging news about brain science and health.

Problems associated with retinal degenerative diseases are due to the injury and death of neurons, or support cells that can't regenerate. The cell types primarily affected are the light-sensing rod and cone photoreceptors and the adjacent retinal pigment epithelium, which maintains proper photoreceptor health and function. If these cells could be replaced or bypassed, sight could be restored.

"So far, a number of human cell sources have been examined to see if they produce multiple retinal cell types, but most candidates have proven inadequate," said Jason S. Meyer, PhD, at University of Wisconsin, the study's lead author. "In comparison, human stem cells have produced cells that are clearly of a retinal nature."

When the stem cells were isolated and matured, specific retinal cell types could be identified, including photoreceptors and retinal pigment epithelium. Using this new system, the authors could regulate the production of certain cell types by adding or removing particular compounds to the cells. "This ability could aid in the discovery of new therapeutic approaches to a variety of disorders affecting the retina," Meyer said. "These findings could lead to treatments for other neurological disorders, in addition to eye diseases."

Research was supported by the National Eye Institute, the Foundation Fighting Blindness, the Lincy Foundation, and the Retina Research Foundation.

Note: If no author is given, the source is cited instead.

• Stem Cells
• Immune System
• Skin Cancer

• Neuroscience
• Hearing Impairment
• Dementia

• Peripheral vision
• Embryonic stem cell
• Retina
• Pupillary reflex
• Somatic cell
• Stem cell treatments