Researchers from the Montreal Neurological Institute and Hospital of McGill University have found that the often overlooked B cells may play a larger than expected role in multiple sclerosis (MS), which could shed light on better treatment. Current beliefs suggest that multiple sclerosis is controlled by T cells that attack the myelin. The new research has revealed the importance of the previously overlooked B cells, which are produced in bone marrow and essential to immune response. Now researchers have found how B cells, too, contribute to MS.
Senior author of the study, Amit Bar-Or, M.D., said, “We’ve recently discovered that different types of human B cells exist. Some B cells have been shown to promote inflammation, while others are actually able to limit inflammation. Our study has implicated a subset of B cells, the GM-CSF producing B cells, as a key contributor in the pro-inflammatory immune cells responses at play in MS.”
The study examined samples of multiple sclerosis patients in comparison to healthy patients. They found B cells were more frequent and more activated in multiple sclerosis patients than in healthy patients. The B cells cause pro-inflammatory responses of myeloid cells in the immune system. After B cell depletion therapy, myeloid cells became less-inflammatory, suggesting the therapy could decrease B cells and prevent new disease activity from occurring.
Dr. Bar-Or added, “The study is significant in discovering a new way by which B cells can contribute to abnormal immune responses in MS which reinforces the rationale for the use of B cell depletion therapy. Furthermore, better identifying the particular subset of B cells responsible for new disease activity, we can look forward to more selectively targeting the ‘bad’ B cells while leaving ‘good’ B cells intact. This is important because B cells normally play key roles in our immune system, so more selective therapies offer the prospect of decreasing the risk of impairing the patients’ immune system in the long run.”