Epstein-Barr virus neutralizing and early antigen antibodies in multiple sclerosis

Background: Our objective was to determine whether antibodies against the Epstein-Barr virus (EBV) nuclear antigen-1 (EBNA-1), early antigen (EA), and EBV neutralizing antibodies (NeutAb) are altered in multiple sclerosis (MS). Methods: We measured EBNA-1 IgG, EA IgG, and EA IgA using quantitative ELISA. We measured NeutAb using a quantitative competitive ELISA. We studied 80 patients with MS, 80 matched controls, and 19 patients with MS with samples collected both whilst stable and in relapse. Results: Epstein-Barr virus nuclear antigen-1 IgG and EA IgA were increased in MS compared to controls. The EBNA-1 index value was 23.3 +/- 18.3 in the patients with MS (mean +/- SD) and 16.3 +/- 17.4 in the controls (P = 0.007, paired t-test). EA IgA had a median value of 1.964 in the patients with MS and 1.248 in the controls (P = 0.029, Wilcoxon signed rank test). EA IgG and NeutAb were not significantly different. None of the antibody levels were altered in relapse. The correlation between concentrations of different antibodies was minimal. Conclusions: IgG antibodies to EBNA-1 are significantly increased in MS. IgA antibodies against EBV EA are also increased. The EBV neutralizing antibody response is similar in MS and controls.