Adapted from Washington University School of Medicine
Studying a mouse model of age-related macular degeneration, the leading cause of blindness in older Americans, scientists at Washington University School of Medicine in St. Louis have found age is key in determining whether damaging blood vessels will form beneath the retina and contribute to vision loss.
The scientists discovered that specific immune cells called macrophages play a role in the disease process in older mice by failing to block the development of abnormal, leaky blood vessels behind the retina. But in younger mice, macrophages typically prevent abnormal blood vessel formation.
The scientists believe better understanding of how macrophages work may provide potential targets for therapies to slow or even reverse vision loss. The findings are reported in the November issue of the Journal of Clinical Investigation.
Age-related macular degeneration is the leading cause of visual impairment in the United States in people over the age of 50. It accounts for more than 40 percent of visual impairment among the elderly in nursing homes, and as baby boomers get older, the problem is expected to grow, with at least 8 million cases predicted by the year 2020.