MCG researchers awarded $275K grant to study HIV and retinopathy correlation

It’s often said that “teamwork makes the dream work,” and scientists from different disciplines at Augusta University are a perfect example of that. Manuela Bartoli, PhD, research director and professor of ophthalmology at AU’s Medical College of Georgia, has joined forces with Eric Belin de Chantemèle, PhD, a physiologist in MCG’s Vascular Biology Center, to explore the link between HIV and retinopathy. 

The pair was recently awarded a two-year $275,000 grant from the National Eye Institute that will allow them to test different variables on a transgenic mouse model and assess how they impact the development of retinopathy.

The project began with Bartoli and Belin de Chantemèle examining transgenic mice that expressed viral proteins linked to HIV. They found that the blood vessels supplying oxygen and nutrients to the mice’s retinas were not functioning properly.

“So, we developed the idea that people living with HIV may be more prone to or progress more rapidly when they get one of the ischemic retinopathies that are very common, particularly diabetic retinopathy and age-related macular degeneration,” Bartoli said. “I think this is important because we’ll basically define a chronic HIV infection as a risk factor for the development of the most severe ocular disease.”

Bartoli’s work focuses on ischemic retinopathies, which are conditions that reduce blood flow, oxygen and nutrients to the retina — the part of the eye responsible for vision. These disorders are the leading cause of blindness around the world. Different types include retinopathy of prematurity, diabetic retinopathy and age-related macular degeneration.

Several factors contribute to ischemic retinopathies, such as oxidative stress and inflammatory processes. Bartoli infers HIV might be another risk factor, but it’s tough to confirm as antiretroviral therapies make the virus nearly undetectable.

“The number of people living with HIV is growing in terms of age, so most likely they will develop, at some point, a disease like age-related macular degeneration, which is really common in the elderly population,” Bartoli said. “We knew the individual has the acute infection, and because of the immunosuppression, they develop a number of infections that lead to retinal dysfunction. There was also reported what is called retinitis due to HIV. But with medication, these acute events disappear, and we don’t know, when you get older and develop one of these diseases, how is it going to progress?”

While cART therapies can manage HIV, Bartoli noted they don’t fix the defective blood vessels in the retina.

And it’s not just the retina. The big picture is that HIV alters blood vessels throughout the human body, therefore elevating blood pressure and causing cardiovascular disease.

“We have blood vessels in every single organ, whether this is the heart, the lungs, the kidneys, the brain, the eyes, they are everywhere,” Belin de Chantemèle said. “As HIV is damaging the vessel, that would lead to dysfunctions in all those different organs.”

“On top of that, people who have HIV usually have additional comorbidities. Very often people become obese, have diabetes,” he continued.

The researchers plan to eventually move beyond mouse models and include human subjects in their study.

“I’m already working with people around to try to get information,” Bartoli said. “For example, in the VA system.”

The ultimate goal is to establish how HIV contributes to the progression of eye diseases, which will hopefully lead to a better understanding of why it happens and how to treat it. 

“If this individual who progresses more rapidly goes to the doctor when they are blind already or semi-blind, it’s too late for anything,” Bartoli said. “Blindness is the primary fear in people, so we’re going to combat the cause to prevent this side effect.”