Single Treatment Protects Myelin and Reverses Paralysis in MS Study in Mice

Researchers working in animal models of multiple sclerosis (MS) report that they may have found a way of better treating — and possibly curing — inflammatory diseases like MS. Specifically, injecting a single dose of biodegradable polymer particles that contained specific myelin molecules into the lymph nodes of mice worked to prevent immune system attacks on myelin, and even reversed paralysis caused by the disease in the mice.

The team, led by Dr. Christopher Jewell, an assistant professor at the University of Maryland Fischell Department of Bioengineering, published their results in the journal Cell Reports in an article titled “Reprogramming the Local Lymph Node Microenvironment Promotes Tolerance that Is Systemic and Antigen Specific.”

MS is characterized by an  immune system attack on the myelin sheath wrapped around the axons, or extensions of nerve cells. Damage done to myelin is known to result in the loss of motor function, among other complications. A number of treatments aim to decrease immune cell activity to lessen such damage, but suppressing the immune system can leave patients more vulnerable to infections.

Jewell and his team are working on an approach that would “reprogram” lymph nodes, the tissues that coordinate immune function in the body, so that they generate immune cells that control the attack against the myelin sheaths, instead of creating inflammatory cells that initiate attacks on myelin.

The polymer particles that the team developed contain myelin self-antigens, and carry regulatory signals that promote the maturation of regulatory immune cells. These cells then migrate to the central nervous system,  where they suppress such attacks. In this way, a healthy immune function is maintained while inflammation is directly suppressed.

“The goal of our work – and that of others in the field – is to expand cells that are both myelin-specific and regulatory in nature,” said Lisa Tostanoski, the study’s first author. “The hope is that these cells can directly suppress inflammation without targeting healthy immune function.”

Using two rodent models, researchers demonstrated that their approach resulted in local changes in the function and types of cells in the lymph nodes and the central nervous system, and that these effects were myelin-specific.

According to the authors, this technique may lead to new ways to reverse paralysis and better treat MS patients.

“This innovative research has the potential to open up a new, highly selective approach to treating multiple sclerosis,” Dr. Bruce F. Bebo, executive vice president of research at the National Multiple Sclerosis Society, said in a press release. Bebo also expressed the hope that further research done to translate these animal results into people might be equally successful.

The team is now working to demonstrate that the therapeutic effects seen in the mice resulted the repair of myelin and re-myelination in the brain. “That represents a goal that is a critical criterion to improve on human MS therapies,” Jewell said.

The National Multiple Sclerosis Society has awarded the team more than $600,000 to further advance its work.