‘Compelling data’
In an accompanying commentary, William H. Robinson, MD, PhD, professor, Division of Immunology and Rheumatology, department of medicine, Stanford (Calif.) University, and a colleague said the study findings “provide compelling data that implicate EBV as the trigger for the development of MS.”
The mechanism or mechanisms by which EBV leads to MS “remain elusive,” the commentary authors write.
“Possibilities include molecular mimicry, through which EBV viral protein sequences mimic human myelin proteins and other CNS proteins and thereby induce autoimmunity against myelin and CNS antigens,” they note.
As other factors, including genetic susceptibility, are important to MS, EBV infection is likely necessary but not sufficient to trigger MS, said the commentary. “Infection with EBV is the initial pathogenic step in MS, but additional fuses must be ignited for the full pathophysiology.”
The commentary authors query whether there may be “new opportunities” for therapy with vaccines or antivirals. “Now that the initial trigger for MS has been identified, perhaps MS could be eradicated.”
In a statement from the Science Media Center, an independent venture promoting views from the scientific community, two other experts offered their take on the study.
Paul Farrell, PhD, professor of tumor virology, Imperial College London, said the paper “provides very clear confirmation of a causal role for EBV in most cases of MS.”
While there’s evidence that a vaccine can prevent the EBV disease infectious mononucleosis, no vaccine candidate has yet prevented the virus from infecting and establishing long-term persistence in people, noted Dr. Farrell.
“So, at this stage it is not clear whether a vaccine of the types currently being developed would be able to prevent the long-term effects of EBV in MS,” he said.
Daniel Davis, PhD, professor of immunology, University of Manchester, United Kingdom, commented that the value of this new discovery is not an immediate medical cure or treatment but is “a major step forward” in understanding MS.
The study “sets up new research working out the precise details of how this virus can sometimes lead to an autoimmune disease,” said Dr. Davis. “There is no shortage of ideas in how this might happen in principle and hopefully the correct details will emerge soon.”
The study received funding from the National Institute of Neurological Disorders and Stroke, National Institutes of Health, National Multiple Sclerosis Society, the German Research Foundation, the National Institutes of Health, and the Howard Hughes Medical Institute. Dr. Ascherio reports no relevant financial relaitonships. Dr. Robinson is a coinventor on a patent application filed by Stanford University that includes antibodies to EBV. Dr. Farrell reports serving on an ad hoc review panel for GSK on EBV vaccines in 2019 as a one off. He has a current grant from MRC on EBV biology, including some EBV sequence variation, but the grant is not about MS. Dr. Davis reports no relevant financial relationships.
A version of this article first appeared on Medscape.com.