If you or a loved one has multiple sclerosis (MS), you probably know that MS is a disease of the central nervous system, which includes the brain, the spinal cord, and the optic nerves. While we don’t know exactly what causes MS, there is evidence that the Epstein-Barr virus (EBV) may play a key role.
There are many different risk factors associated with MS. The interplay between environmental (smoking, vitamin D, and EBV) and genetic factors (family history, genes) determines a person’s overall risk of getting MS. While all these factors can play a role, being EBV positive (EBV+) is the only risk factor that may be required for the development of MS.
In MS, damage to nerves occurs throughout the central nervous system (CNS), which includes the brain, the spinal cord, and the optic nerves. The damage to myelin throughout the CNS causes the debilitating symptoms of MS.
Although it is not clear exactly how EBV may be involved in the development of MS, research suggests that people with MS are unable to properly control the number of EBV-infected B cells in their bodies. This may allow the infected B cells to accumulate in the brain, where they interact with and instruct other immune cells called T cells to attack myelin.
Additionally, these EBV-infected B cells produce antibodies, some of which may also attack myelin.
Under normal conditions, T cells bind to EBV-infected B cells.
T cells then destroy EBV-infected B cells, keeping their numbers in check.
In MS, the immune system doesn't function properly, which may allow EBV-infected B cells to accumulate and enter the brain.
Inside the brain, EBV-infected B cells may instruct T cells to attack myelin.
EBV-infected B cells also produce antibodies, some of which may attack myelin.
Together, this autoimmune response may cause the destruction of myelin, leading to the symptoms of MS.
National Multiple Sclerosis Society
Multiple Sclerosis Association of America (MSAA)
The Consortium of Multiple Sclerosis Centers (CMSC)