Persistent EBV Antibody Signal May Aid Multiple Sclerosis Diagnosis Over MOGAD, NMOSD

New findings from a multicenter, retrospective case-control study published in JAMA Neurology suggest that persistently high Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA-1) peptide antibody titers may help differentiate multiple sclerosis (MS) from myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) and neuromyelitis optica spectrum disorder (NMOSD).¹ The analysis, which included 2091 patients with neuroinflammatory disease and 1976 healthy controls, showed that longitudinal patterns of EBNA-1 antibody elevation—rather than single timepoint measurements—were strongly associated with MS diagnosis.¹

Differentiating MS from related neuroinflammatory disorders remains a key clinical challenge, particularly in seronegative NMOSD or borderline MOG-IgG cases. Although disease-specific antibodies have improved diagnostic accuracy, overlap in clinical and imaging features continues to complicate decision-making, reinforcing the need for additional biomarkers.

Across both derivation and validation cohorts, persistently elevated EBNA-1 antibody titers emerged as the clearest distinguishing feature of MS. In the test cohort, 177 of 184 patients with MS (96.2%) had high-level EBNA-1 titers in at least 2 of 4 longitudinal samples, compared with just 5 of 65 patients with MOGAD (7.7%) and 11 of 61 with NMOSD (18.0%) (odds ratio [OR], 303.4 and 114.9, respectively).

These findings were replicated in the independent validation cohort, where 135 of 142 patients with MS (95.1%) demonstrated persistent high titers, compared with 4 of 24 patients with MOGAD (16.7%) and 3 of 17 with NMOSD (17.6%) (OR, 96.4 and 90.0, respectively).¹

Importantly, high-level EBNA-1 titers present at all 3 or 4 time points were observed exclusively in patients with MS. In contrast, patients with MOGAD and NMOSD showed declining antibody titers over time, suggesting a more transient immune response rather than the sustained elevation seen in MS.

The study also demonstrated strong diagnostic performance, with repeated high EBNA-1 titers (≥2 samples) achieving diagnostic accuracy of 95.2% for MS vs MOGAD and 92.7% vs NMOSD. Notably, this longitudinal marker outperformed cerebrospinal fluid oligoclonal bands in differentiating MS from comparator diseases in the analyzed cohort.

Relevance in Seronegative and Ambiguous Cases

The findings were particularly notable in seronegative NMOSD, where diagnostic uncertainty is often greatest. Among patients with NMOSD who were seronegative for aquaporin-4 IgG, only 1 of 9 patients (11.1%) demonstrated persistent high EBNA-1 titers, compared with 96.7% of matched patients with MS (OR, 236.0).¹

Additionally, longitudinal kinetics revealed that EBNA-1 titers in MS remained consistently elevated, whereas titers in MOGAD and NMOSD declined over time. In an independent cohort, a follow-up interval of approximately 4.6 months was sufficient to distinguish persistent from transient antibody responses.

These data reinforce the concept that serial measurement—not a single snapshot—drives clinical utility, particularly in diagnostically uncertain presentations.

Clinical Context and Biomarker Positioning

Study author Tanuja Chitnis, MD, Division Chief of Neuroimmunology at Brigham and Women’s Hospital and Professor of Neurology at Harvard Medical School, emphasized that EBNA-1 antibodies should be viewed as complementary rather than definitive.

“This could be a differentiating factor, maybe a biomarker that we can partially use to suggest that a patient may have multiple sclerosis compared to one of the other diagnoses,” she said.

She noted that the biomarker may be most impactful when integrated with existing tools. “If a patient has it and is positive and has all the other features of multiple sclerosis and MRI features, then I feel more confident in the diagnosis,” she said. “On the flip side, if they don’t have EBNA-1 antibodies, it does give me pause.”

Chitnis also highlighted the evolving nature of EBV-related biomarkers in MS. “EBNA-1 might be a contributor to this, but it might be a panel of antibodies or even a panel of factors,” she said, pointing to ongoing work aimed at improving specificity and early diagnostic accuracy.

Looking Ahead

While the findings support EBNA-1 antibody kinetics as a promising adjunct biomarker, limitations include the retrospective design and the small subset of patients with MS who did not exhibit persistent antibody responses. Prospective validation studies will be needed to confirm clinical utility and determine how best to integrate EBV-related markers into diagnostic workflows.

For now, the data provide a strong signal that longitudinal EBV serology may help refine the differential diagnosis of MS, particularly in cases where traditional biomarkers fall short.¹

REFERENCE
1. Vietzen H, Kuhner LM, Berger SM, et al. Epstein-Barr Virus Antibodies to Differentiate Multiple Sclerosis From Other Neuroinflammatory Diseases. JAMA Neurol. Published online March 9, 2026. doi:10.1001/jamaneurol.2026.0240