Human Stem Cells Are Found to Help Rats’ Vision (New York Times, 9/21)

[muesa]

Pointing the way to a possible clinical use of human embryonic stem cells, researchers have improved vision in rats suffering from a disease similar to age-related macular degeneration.

The scientists, at Oregon Health and Science University, used human embryonic stem cells that had spontaneously converted into the special cells that line the base of the retina. The cells, which support the light-sensing rod and cone cells above them, are damaged in some forms of macular degeneration.

A group led by Raymond Lund says members injected these human cells into the retina of a special breed of rat in which the retina degenerates shortly after birth. The cells rescued the rats’ vision, as judged by several tests, for three months after birth, the researchers report today in the journal Cloning and Stem Cells.

The injected human cells seemed to behave as retinal cells should, and the treated rats retained some six layers of rods and cones in their retinas, as much as half the normal value.

The human retinal lining cells, derived from different cultures of embryonic stem cells, were supplied by Advanced Cell Technology, a company with laboratories in Worcester, Mass. Dr. Neal Adams of the Wilmer Eye Institute in Baltimore said the development was important and “shows us some of the hope that regenerative medicine possesses.” But many more stages lie ahead before any clinical test of the cells in patients with macular degeneration could be tried, Dr. Adams added.

Macular degeneration is a good candidate for embryonic stem cell therapy, at least in principle, because the eye is not closely monitored by the immune system. So cells from another individual could be grafted with lesser risk of rejection than at other sites.

Read the article---

1. Not the same etiology as "age related macular degeneration" or "diabetic macular degeneration".
   
2. Rodent etiologies and therapies to not map 1:1 to humans.

But - it's good progress.

[jilln]

1. good news for rats!!! (nt)