Scientists work towards creating a vaccine for Parkinson's disease

Nina Brown, 68, and millions of others with a debilitating neurological condition called Parkinson's disease are counting on researchers for a cure. At The University of Texas Health Science Center at Houston (UTHealth), protein chemists are working to develop a therapeutic vaccine.

Parkinson's disease is a chronic disorder that worsens over time and can rob people of their ability to perform everyday tasks. Named after the English doctor who described the condition almost 200 years ago, its symptoms often include tremors or shaking, slow movements, stiffness in arms and legs, drooling, slurred speech and unsteadiness.

"We're creating a vaccine to target a protein that accumulates in the brains of people with Parkinson's disease," said Rowen Chang, Ph.D., who is the professor leading the research project at the UTHealth Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases (IMM). "If we can slow the protein buildup, I believe we will also slow the deterioration of nerve cells tied to body movement." The protein is alpha synuclein.

People with Parkinson's disease may appear to be fixed in their facial expressions, stooped forward in their posture and may even appear to be intoxicated to others because of their postural instability. While there is no cure, the symptoms of Parkinson's disease can be treated effectively. Parkinson's disease is the second most common of the progressive neurological diseases, affecting 1 percent of the population over the age of 60.

Brown, who was diagnosed in 1985 after experiencing balance problems, used to swat tennis balls and take in traveling productions of Broadway shows. "I went from being able to walk, to using a cane, to using a walker, to now using a scooter," said Brown, who lives in Bellaire, Texas, and has been married to Joe Brown for 48 years.

Turning lemons into lemonade, Nina Brown is not letting Parkinson's disease slow her down. The picture shows Brown and her husband, Joe, when she was able to walk a 5K several years ago.

"We estimate that there are about 19,000 people with Parkinson's disease in the greater Houston area," said Kathleen Crist, director of social services and program development for the Houston Area Parkinson Society, a nonprofit social service. "For every person with it, there are also family members affected."

Parkinson's disease has been linked to cell death in the substantia nigra, which is responsible for modulating movement and produces a major brain chemical messenger called dopamine. Dopamine directs the signals that allow people to control their movements.

For years, vaccines have been used to protect people from diseases like rubella and measles by stimulating their immune systems. So, why not develop a therapeutic vaccine for Parkinson's disease?

When a person gets vaccinated, he or she is injected with a tiny amount of an agent linked to a disease, said Chang, who is collaborating on the project with UTHealth researcher and assistant professor Chuantao Jiang, M.D., Ph.D. As soon as the immune system recognizes this agent, it begins to produce antibodies to attack it. The agents that trigger this process are called immunogens.

Building on pre-clinical vaccine research by others demonstrating that reducing alpha synuclein buildup also reduces nerve damage, Chang and Jiang have developed an approach that they believe will be more effective in reducing alpha synuclein levels and therefore provide a more effective form of Parkinson's disease therapy.

Their work is supported by a grant from The Michael J. Fox Foundation for Parkinson's Research, founded by Emmy Award-winning actor Michael J. Fox, who was diagnosed with Parkinson's disease in 1991.

Chang and Jiang, who work in the UTHealth Center for Protein Chemistry, have developed a vaccine and are in the process of testing its safety and effectiveness in a mouse model that expresses the human alpha synuclein protein.

The first part of their study involved a comparison of three different immunogens. "We have found a highly promising immunogen that may prevent the alpha synuclein aggregation," Jiang said. The next step is gauging the effects of the immunogen in a mouse model.

If the immunogen works in mice, clinical trials could be in the offing, Chang said.

Other Parkinson's disease research underway at UTHealth includes a clinical study designed to aid in the early diagnosis of the disease, which scientists believe starts long before the onset of impaired motor skills.

Mya Schiess, M.D., professor and Adriana Blood Chair in Neurology at the UTHealth Medical School, and colleagues are trying to build a profile of measures that could be used to predict Parkinson's disease development.

The scientists are searching for biological substances and physiological phenomena (biomarkers) tied to the disease, which could be used in combination with other measures, such as a reduction in the ability to smell, to diagnose the disease. The study includes people with Rapid Eye Movement Sleep Behavior Disorder, who are at increased risk of developing Parkinson's disease. For information on the study, call 713.500.7073.

"I hope a cure for Parkinson's will be forthcoming in my lifetime," said Nina Brown, who describes her battle with Parkinson's disease in a video titled "Hope." "If not, it is my hope that it will be there for future generations."

Joe Brown added, "The answers won't come immediately. But when they do, they will change mankind."