EBV viral load and miR-BART10-3p expression in multiple sclerosis: A case-control study

The Epstein-Barr virus (EBV) is associated with multiple sclerosis (MS), but the underlying molecular mechanisms are not fully understood. This case-control study from Southern Iran investigated the association of EBV viral load and EBV-encoded miR-BART10-3p expression with MS.

The study included 110 participants: 40 newly diagnosed MS patients (ND-MS), 20 patients treated with interferon-β (MS-IFN), 20 patients receiving B-cell-depleting monoclonal antibody therapy (MS-mAb), and 30 age- and sex-matched healthy controls (HC). Peripheral blood samples were collected, and the isolated buffy coat fractions and sera were stored at -70 °C until analysis. Total DNA and RNA were extracted from the buffy coat using TRIzol reagent. EBV genomic load per cell and EBV-encoded microRNA BART10-3p expression were quantified by q-PCR and q-RT-PCR, respectively. EBV viral capsid antigen (VCA) IgG serostatus was determined by ELISA.

The mean age of the participants was 37.7 ± 8.5 years (range: 22-61). The cohort consisted of 26 (32.5%) males in the patient group (n = 80) and 10 (33.3%) in the HC group (n = 30). EBV viral load was significantly elevated in the ND-MS (2.1-fold increase; p < 0.001) and MS-IFN (1.7-fold increase; p = 0.03) groups compared to HCs. In contrast, the MS-mAb group showed a lower, non-significant viral load (0.2-fold; p = 0.17). Similarly, miR-BART10-3p expression was significantly higher in ND-MS (mean = 4.06; 2.74-fold increase; p < 0.001) and MS-IFN (mean = 2.91; 1.97-fold increase; p < 0.001) groups, but it was markedly lower in the MS-mAb group (mean = 0.43; 0.29-fold; p < 0.001). No significant differences in EBV-VCA IgG seropositivity were observed among the groups (p = 0.55). Furthermore, EBV viral load, miR-BART10-3p expression, and EBV-VCA IgG seropositivity showed no significant association with the age or sex of the participants (p > 0.05).

These findings suggest a potential role for EBV viral load and miR-BART10-3p expression in the pathogenesis of MS. These molecular markers may serve as complementary indicators for monitoring EBV activity and disease progression. Further studies are needed to validate these results and explore their clinical utility.