August 14, 2014

VEI taking novel approach to fight blinding diseases

Personalized medicine — the effort to tailor health care to individual patients’ needs, genetic profiles and circumstances — is a well-established concept at Vanderbilt University Medical Center.

Personalized medicine — the effort to tailor health care to individual patients’ needs, genetic profiles and circumstances — is a well-established concept at Vanderbilt University Medical Center.

Milam Brantley Jr., M.D., Ph.D., director of the Vanderbilt Eye Institute’s Initiative for Personalized Medicine in Ophthalmology, has added another layer to Vanderbilt’s campuswide plan for establishing customized treatment plans for patients.

Milam Brantley Jr., M.D., Ph.D., right, talks with patient David Nipper at the Vanderbilt Eye Institute. Brantley and colleagues are working to identify metabolites that could serve as biomarkers for risk of developing the primary diseases that cause blindness. (photo by Joe Howell)

Using a novel technique called metabolomics, which provides a snapshot of thousands of molecules called metabolites in a person’s blood, Brantley and colleagues are conducting studies to identify metabolites that can serve as biomarkers for determining a person’s risk of developing any of the three leading causes of blindness.

Nationwide, these three diseases — diabetic retinopathy, age-related macular degeneration and glaucoma — affect nearly 20 million people combined.

Brantley and his research assistants are currently recruiting VEI patients for the studies.

Participants undergo a blood draw and answer basic health-related questions. The metabolomic analysis of the samples is performed at Emory University in collaboration with metabolomics expert Dean Jones, Ph.D., who currently directs the Emory Clinical Biomarkers Laboratory. The data is combined with genetic information to create a “metabologenetic” profile for a group of patients.

Brantley and his team recently recruited their 1,000th study participant. In September 2013, he received a five-year, $1.7 million grant from the National Eye Institute to investigate metabolic and genetic profiles in age-related macular degeneration (R01EY022618).

“We are fortunate that our collaboration with Dean Jones has allowed us to be at the forefront of ocular metabolomics research,” Brantley said.

“If we can determine who is most likely to develop sight-threatening diseases, then we have a better chance of intervening early and preventing vision loss,” he said. “The long-term goal of our research is to develop individualized treatment plans for patients with eye diseases.”

Brantley is encouraged that the analysis has detected a group of four metabolites that appear to be associated with diabetic retinopathy in patients with diabetes. He hopes that this discovery will help him pinpoint markers for the development and progression of all blinding eye diseases.

“We envision a time when a routine blood draw could help predict a patient’s course of disease and response to treatment based on his/her unique genetic and metabolic profiles,” said Brantley. “This could lead to timely detection of advanced disease and earlier identification of effective treatment, optimizing visual outcomes.”

David Calkins, Ph.D., Denis M. O’Day Professor of Ophthalmology and Visual Sciences, vice-chair and director for Research, said that since patients’ diseases progress at different rates and many do not respond to first-line treatments, the work Brantley is undertaking is imperative to the future of ophthalmology.

“Dr. Brantley’s research addresses the mechanisms underlying individual differences like these and will allow us to sculpt personalized treatment plans for blinding eye disease,” Calkins said.

“His initiative is at the forefront of ending the era of ‘one size fits all’ for ophthalmology.”
The number of patients who have volunteered to provide blood samples is encouraging to the team, said Brantley.

“They are giving their time and a blood sample for research that won’t necessarily benefit them directly,” he said. “But what they are doing will aid in our efforts to assist others. We are planning to expand this research to include other blinding eye diseases such as optic neuropathy and retinal vein occlusion.”