Summary Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system of unknown etiology. We tested the hypothesis that MS is caused by Epstein-Barr virus (EBV) in a cohort composed of more than 10 million young adults on active duty in the US military, 955 of whom were diagnosed with MS during their period of service. The risk of MS increased 32-fold after EBV infection, but did not increase after infection with other viruses, including similarly transmitted cytomegalovirus. Serum levels of neurofilament light chain, a biomarker of neuroaxonal degeneration, increased only after EBV seroconversion. These findings cannot be explained by any known risk factors for MS and suggest that EBV is the main cause of MS. |
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Multiple sclerosis (MS), a progressive disease that affects 2.8 million people worldwide and for which there is no definitive cure, is likely caused by infection with the Epstein-Barr virus (EBV), according to a study led by the Harvard TH Chan School. Public Health Researchers.
“The hypothesis that EBV causes MS has been investigated by our group and others for several years, but this is the first study to provide convincing evidence of causality,” said Alberto Ascherio, professor of epidemiology and nutrition at the Harvard Chan School. and lead author of the study. study. "This is a big step because it suggests that most cases of MS could be prevented by stopping EBV infection, and that targeting EBV could lead to the discovery of a cure for MS."
MS is a chronic inflammatory disease of the central nervous system that attacks the myelin sheaths that protect neurons in the brain and spinal cord. Its cause is unknown, but one of the main suspects is EBV, a herpes virus that can cause infectious mononucleosis and establishes a lifelong latent infection in the host.
It has been difficult to establish a causal relationship between the virus and the disease because EBV infects approximately 95% of adults, MS is a relatively rare disease, and the onset of MS symptoms begins about ten years after infection. VBS.
To determine the connection between EBV and MS, researchers conducted a study of more than 10 million young adults on active duty in the U.S. military and identified 955 who were diagnosed with MS during their tour of duty.
The team analyzed serum samples taken every two years by the military and determined the soldiers’ EBV status at the time of the first sample and the relationship between EBV infection and the development of MS during the active duty period.
In this cohort, the risk of MS increased 32-fold after EBV infection, but did not change after infection with other viruses. Serum levels of light chain neurofilaments, a biomarker of nerve degeneration typical of MS, increased only after EBV infection. The findings cannot be explained by any known risk factors for MS and suggest that EBV is the main cause of MS.
Ascherio says the delay between EBV infection and the onset of MS may be due in part to the disease’s symptoms going undetected during the early stages and in part to the evolving relationship between EBV and the immune system. host, which is repeatedly stimulated each time the latent virus is reactivated.
“Currently, there is no way to effectively prevent or treat EBV infection, but an EBV vaccine or targeting the virus with EBV-specific antiviral drugs could ultimately prevent or cure MS,” Ascherio said. .
Other Harvard Chan School researchers who contributed to this study include Kjetil Bjornevik, Marianna Cortese, Michael Mina, and Kassandra Munger.
Funding for this study came from the National Institute of Neurological Disorders and Stroke, the National Institutes of Health (NS046635, NS042194, and NS103891), the National Multiple Sclerosis Society (PP-1912-35234), the German Research Foundation (CO 2129/1-1), the National Institutes of Health (DP5-OD028145), and the Howard Hughes Medical Institute.
“ Longitudinal analysis reveals high prevalence of Epstein-Barr virus associated with multiple sclerosis ”, Kjetil Bjornevik, Marianna Cortese, Brian C. Healy, Jens Kuhle, Michael J. Mina, Yumei Leng, Stephen J. Elledge, David W. Niebuhr, Ann I. Scher, Kassandra L. Munger, Alberto Ascherio, Science, January 13, 2022, doi: 10.1126/science.abj8222
