Scientists in Sweden have taken an important step forward in understanding how a very common virus, called Epstein-Barr virus (EBV), might be linked to multiple sclerosis (MS), a serious disease that affects the brain and spinal cord.
The new study, led by researchers at the Karolinska Institutet and published in Science Advances, offers clues that may help explain why some people develop MS after being infected with EBV.
EBV is one of the most widespread viruses in the world. More than 90% of people around the globe carry it. It usually infects people early in life and stays in the body forever, though most people never even know they have it.
For young children, the infection often causes no symptoms at all. But if people first catch EBV as teenagers or young adults, it can cause a sickness called mononucleosis, or “mono,” which is also known as glandular fever or the “kissing disease.”
Although scientists have known for years that EBV is somehow connected to MS, they didn’t fully understand how. MS is a complicated disease where the body’s immune system mistakenly attacks parts of the nervous system, damaging the protective layer around nerves. This damage leads to symptoms like tiredness, trouble walking, and problems with balance or vision.
In this new study, the researchers looked at blood samples from more than 700 people with MS and another 700 healthy people. They focused on antibodies—proteins made by the immune system to fight infections. Normally, antibodies attack viruses and bacteria to keep us healthy. But sometimes, they make a mistake and attack the body’s own tissues.
The scientists found that some people with MS had antibodies that could stick to a protein in EBV called EBNA1. But what was surprising is that these same antibodies could also stick to a protein in the brain and spinal cord called CRYAB.
This protein normally helps protect brain cells during stress, like inflammation. When the antibodies attack it by mistake, they may harm the nervous system instead of helping the body.
This type of “cross-reaction”—where the immune system confuses the body’s own proteins with those from a virus—might be part of how MS starts or gets worse. The researchers found these cross-reacting antibodies in about 23% of people with MS, compared to just 7% of the healthy group. That means this immune mix-up may affect up to a quarter of people with MS.
Olivia Thomas, one of the study’s lead authors, explained that these findings don’t mean the antibodies cause MS in everyone. But in some people, they might play a key role in triggering or worsening the disease. This helps explain why MS is so different from person to person and shows the need for treatments that are tailored to each patient.
The team also found hints that another part of the immune system—T cells—might be doing something similar. T cells are like soldiers that attack infected or dangerous cells. The researchers now want to find out whether T cells that are supposed to fight EBV are also harming the nervous system in people with MS.
Mattias Bronge, another lead author, said the next step is to study how these T cells respond to EBV and whether they might also be damaging the brain and spinal cord. If they are, this could give scientists another way to target MS with new treatments.
Overall, this research gives doctors and scientists a clearer picture of how a very common virus could be linked to a very serious disease. Understanding this connection better may one day lead to more precise, personalized ways to prevent or treat MS.
If you care about health, please read studies that vitamin D can help reduce inflammation, and vitamin K could lower your heart disease risk by a third.
For more health information, please see recent studies about new way to halt excessive inflammation, and results showing foods that could cause inflammation.
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