Scientists say B cells can be beneficial, but too many can bring on MS symptoms.
A
B cells provide a defense against pathogens in our bodies. And sometimes more is better.
But for those living with MS, this could present a problem. Too many B cells could lead to neurological damage.
Researchers from the Technical University of Munich concluded that when certain control cells are missing, the B cells can accumulate and cause inflammation in the nervous system.
Using both animal and human samples, the team focused on control cells, known as myeloid-derived suppressor cells, and their effect on B cells.
The results indicated that people with higher amounts of these suppressor cells showed milder MS symptoms. Those with lower numbers of the cells experienced worse symptoms.
This study shows why some current treatments work based on B cells.
“We are getting an ever-growing appreciation for the role(s) that B cells play in MS pathogenesis. One of our newest and more effective disease-modifying therapies, ocrelizumab, is directed against a particular B cell,” said Dr. Barbara Giesser, professor of clinical neurology at the David Geffen School of Medicine at the University of California at Los Angeles (UCLA) and clinical director of the UCLA MS program.
“This study reports new information about the ways that B cells and their interactions with other cells contribute to damage in the central nervous system in a mouse model. These findings, if confirmed in humans and expanded, may suggest new therapeutic targets,” Giesser told Healthline.
Future research may show exactly how the B cells destroy the nervous system.
Dr. Thomas Korn, a professor of experimental neuroimmunology at the TUM Neurology Clinic in Germany and study co-author, explained that the broader perspective of the study is that “by exploiting the regulatory loop, we found the intrathecal B cell compartment, which might be a driver of chronic disease in MS and could be better targeted in therapeutic interventions.”
Elisabeth Mari, PhD, the director of biomedical research for the National Multiple Sclerosis Society, emphasizes the importance of learning more about the role of B cells and disease progression.
“We knew B cells play a role. We are now understanding how this role is coming to be. Earlier research focused on T cells. And we know T cells and B cells interact. This ability of the B cells to produce antigens through the T cells could lead to progression,” Mari told Healthline.
“The study gives us more insight into the roles and mechanisms of not only B cells, but other cells in the body that might be playing a role in shaping the B cells to be more destructive,” she said.
Understanding cells’ mechanisms helps scientists to understand diseases.
“This paper adds another layer of understanding in the central nervous system as a result of B cells,” Mari said. “When we take the B cells out of the mix we are learning their functions, both good and bad. In B cell therapies such as ocrelizumab, the B cells that repopulate are more helpful.”
“This means we are understanding more about the pathways and the cells involved in MS and particularly with progression. We need to understand better how B-cell therapies work and find other therapies for people,” she added.
Mari told Healthline that overall interest in B cell biology has increased, mainly because of ocrezimulab.
“Cells in our bodies have ability to do incredible things. They live in an incredible balance, but nudge one thing off-kilter just a bit and see what happens in the body: cancer and autoimmune diseases,” Mari explained.
“When we look at untreated MS patients we see indication that there is some relationship between these two populations of cells and how they are interacting,” she said. “We know B and T cells can be bad, but how the cells interact will provide more insight into both relapsing MS and progressive MS.”
“Possibly this is tested in the future and used as a tool to manage medicine and disease progression,” Mari said.
Editor’s note: Caroline Craven is a patient expert living with MS. Her award-winning blog is GirlwithMS.com, and she can be found on Twitter.