The common virus Epstein-Barrwhich causes the mononucleosiscauses an immune system reaction that can damage the brain and contribute to multiple sclerosis (MS), according to new research by Sweden’s Karolinska Institute.
The hypothesis that the Epstein-Barr virus (EBV) causes multiple sclerosis has been studied for years by various scientific groups. Now, the new research, published in the journal Cellprovides new data that confirms the relationship between both pathologies.
Almost three million people in the world have multiple sclerosis, a chronic inflammatory disease without curein which the immune system attacks the central nervous system and damages neurons and spinal cord.
It is known that all people who develop sclerosis have had infectious mononucleosis or ‘kissing disease’, caused by a virus that usually infects young people and often has no symptoms, but It is still not well known how this virus contributes to sclerosis..
The new study shows that when the immune system fights the Epstein-Barr virus, certain T cells—which normally attack the virus—also They can react and .
This phenomenon, called molecular mimicry, causes immune cells confuse the body’s own proteins with those of the virus.
The team also discovered that these cross-reactive T cells are significantly more common in people with sclerosis than in healthy people.
“Our results provide mechanical testing that immune responses to the virus can directly damage the brain in sclerosis. It is a complex neurological diseaseand it is possible that the molecular mechanisms vary between patients,” says the first author of the study, Olivia Thomas, from the Institute’s Department of Clinical Neuroscience.
blood samples
The study is based on previous research that showed that mistargeted antibodies after Epstein-Barr virus infection may play an important role in the development of sclerosis.
To confirm this, the team analyzed blood samples from people with sclerosis and compared them with healthy people.
The researchers were able to isolate T cells who react so much to EBNA1 protein of the virus as well as the ANO2 of people with sclerosis.
Additionally, experiments in a mouse model showed that these cells can exacerbate sclerosis-like symptoms and cause brain damage.
For the authors, these results help explain why some people develop sclerosis after an Epstein-Barr infection and others not.
Although there is currently no way to effectively prevent or treat Epstein-Barr infection, scientists believe that a vaccine against this virus or attacking it with specific antiviral drugs could help prevent or cure multiple sclerosis.
Therefore, this discovery “opens the door to new targeted treatments to these cross-reactive immune cells. “Given that several Epstein-Barr virus vaccines and antiviral drugs are currently being tested in clinical trials, the results may be of great importance for future preventive and therapeutic efforts,” said Tomas Olsson, co-director of the study with Andre Ortlieb Guerreiro-Cacais, both from the Karolinska Institutet.