LEXINGTON, Ky. (June 15, 2009) A team of researchers led by Dr. Jayakrishna Ambati at the University of Kentucky has discovered a biological marker for neovascular age-related macular degeneration (AMD), the leading cause of blindness in older adults.
The marker, a receptor known as CCR3, shows strong potential as a means for both the early detection of the disease and for preventive treatment. The findings were reported in an article published online Sunday by the prestigious journal Nature.
"This is a major paradigm shift in macular degeneration research," said Ambati, a professor of physiology, professor and vice-chair of ophthalmology and visual sciences, and the Dr. E. Vernon and Eloise C. Smith Endowed Chair in Macular Degeneration at the UK College of Medicine. "With CCR3, we have for the first time found a unique molecular signature for the disease. This brings us closer than we have ever been to developing a clinical diagnostic tool to discover and treat the disease early, before vision is lost."
Neovascular (or "wet-type") macular degeneration is caused by choroidal neovascularization (CNV) the invasive growth of new blood vessels in the thin vascular layer that provides nourishment and oxygen to the eye. Central vision loss occurs when these abnormal blood vessels invade the retina, the light-sensitive tissue that lines the inner surface of the eyeball.
"Once the vessels invade the retina, the horse has already left the barn," Ambati said. "At that point, drugs can slow the process, but irreparable damage has often already been done. This is why finding a means for early detection and intervention is so important."
Drs. Atsunobu Takeda, Judit Z. Baffi, Mark E. Kleinman, Won Gil Cho and other researchers in the Ambati laboratory discovered that CCR3 a molecule also implicated in inflammatory processes is expressed on the surface of CNV vessels in humans but is absent from normal vascular tissue.
|Contact: Keith Hautala|
University of Kentucky