Impaired control of autoimmunity increases pediatric multiple sclerosis risk in EBNA-1-seropositives and -seronegatives.

Impaired natural killer cell regulation, not EBV infection alone, drives pediatric multiple sclerosis risk, with 92.2% of EBNA-1 seropositive patients showing CNS autoantibodies.

• Why it matters: Understanding the mechanisms behind MS development is crucial because CNS-specific autoimmune responses can occur independently of EBV infection, highlighting gaps in current knowledge about disease triggers and immune regulation.
• What they did: The study analyzed 548 EBNA-1 seropositive and 30 seronegative pediatric MS patients, along with matched controls, measuring CNS-specific autoantibodies and immune cell activity, especially NK cell regulation.
• The result: Findings reveal that CNS autoimmunity is amplified by EBV but can occur without it, and that defective NK cell control of autoreactive responses increases MS risk, suggesting immune regulation as a key factor.