Are we on the verge of an epidemic of vision loss?
Considering the large number of baby boomers and the prevalence of macular degeneration among older adults‚ it’s possible. As a result‚ a sense of urgency propels research in the lab headed by Deborah Ferrington, Ph.D., an associate professor in the University of Minnesota Departments of Ophthalmology and Biochemistry, Molecular Biology, and Biophysics.
Ferrington studies the cellular mechanisms involved in the retinal degeneration that accompanies aging and age-related macular degeneration.
The retina is the part of the eye that captures light rays and turns them into electrical impulses‚ which are then converted into the images we see. “My lab looks at how proteins in the retina change with aging and with age-related macular degeneration‚” Ferrington explains. “We focus on the proteins because they are the components of the cell that do the cell’s work.”
Many studies have looked only at end-stage macular degeneration‚ where there is total degeneration and the person is legally blind. Ferrington is more interested in learning about the very early stages of the disease and concentrating on understanding how retinal proteins change.
Sophisticated research techniques allow scientists in her lab to look at thousands of proteins at once and compare the number of retinal proteins in a healthy younger person with the number found in a healthy older person.
Another aspect of the study will compare the retinal proteins in a healthy aging person with those in a person with age-related macular degeneration.
Ferrington’s group collaborates with colleagues at Emory University to evaluate the tissue samples. Scientists at the University of Minnesota‚ using donor eyes from the Minnesota Lions Eye Bank‚ dissect and photograph retinas and then send the photographs to Timothy Olsen‚ M.D.‚ a macular degeneration expert at Emory‚ who evaluates the stage of macular degeneration present in the donor’s eyes.
“This is a very important aspect of our research because the system we have in place is based on the same grading system used for patients‚” Ferrington says. “That means what we find in the lab has direct application to the patient in the clinic.”
Not many labs use donated human eyes for this type of research. The cultured cells or animal models used in some labs make it almost impossible to replicate macular degeneration because the macula—the center part of the retina that is responsible for high-detail vision—is unique to humans and nonhuman primates‚ Ferrington says.
“Using human donor eyes is more expensive‚ but it puts us ahead of many labs in the country in terms of the quality of the research‚” she says.
While scientists have yet to define exactly what causes agerelated macular degeneration‚ they are getting closer to finding the answer. Recent scientific papers describe alterations in the immune system‚ but finding the pathway by which vision may be repaired remains elusive.
“This is ultimately what we hope to do‚ of course‚” says Ferrington. “If we can interrupt macular degeneration in its early stages‚ we hope to slow down the process with drugs that show promise or‚ better yet‚ even stop the progression of the disease.”
The Minnesota Lions Eye Bank accepts donations of healthy eyes for corneal transplantation and also eyes with disease for research like Ferrington’s. For more information about becoming an eye donor‚ visit www.mnlionseyebank.org/about-donation/becoming-a-donor.html.