WEDNESDAY, Jan. 12, 2005 (HealthDayNews) -- Using an antibody to block the action of a protein called SDF-1 prevented blindness in mice with a condition similar to retinopathy in humans, says a University of Florida study in the current issue of the Journal of Clinical Investigation.
Retinopathy -- characterized by rampant blood vessel growth in the eyes -- is a complication of diabetes and the leading cause of blindness in working-age Americans. Diabetic retinopathy results in 12,000 to 24,000 cases of blindness in the United States each year, says the American Diabetes Association.
This study is the first to describe a link between SDF-1 and retinopathy. It also describes how the researchers injected an SDF-1 antibody into the eyes of the afflicted mice to silence SDF-1's signaling to blood stem cells.
"SDF-1 is the main thing that tells blood stem cells where to go," researcher Edward Scott, director of the program in stem cell biology and regenerative medicine at the university's College of Medicine, said in a prepared statement.
"If you get a cut, the body makes SDF-1 at the injury site and the repair cells sniff it out. The concentration of SDF-1 is higher where the cut occurs and it quickly dissipates. But the eye is such a unique place, you've got this bag of jelly -- the vitreous -- that just sits there, and it fills up with SDF-1. The SDF-1 doesn't break down. It continues to call the new blood vessels to come that way, causing all the problems," Scott explained.
In people with diabetes, high blood pressure and blood sugar levels cause leaks in the blood vessels of the eyes. This hampers the flow of essential chemicals. In response, the eyes grow new blood vessels. These new blood vessels begin to clog the eyes and cause even more leaks. The retina is gradually damaged until it can no longer capture images.
The next step in this research is to test the SDF-1 antibody in monkeys, the researchers said.
More information
The U.S. National Eye Institute has more about diabetic retinopathy.
