#MSBlog: EBV & MS in India; what is it telling us about MS causation?
OBJECTIVES: Epstein-Barr virus (EBV) seroprevalence is high from early childhood in Indian populations, though MS is uncommon. The present study aims to evaluate the association of EBV infection with MS in Indian MSers.
METHOD: In this study 140 MSers and equal number of matched controls were included. Estimation of serum Immunoglobin G (IgG) for EBV Nuclear antigen 1 (EBNA1), viral capsid antigen (EBV-VCA) and early antigen (EB-EA) were obtained by quantitative enzyme linked immunosorbent assay (ELISA). MSers and controls were genotyped for the human leucocyte antigen (HLA) DRB1*1501 allele.
RESULTS: A modest difference was observed for EBNA1 (p=0.02) and EBV-VCA (p=0.03) titres in MSers as compared to healthy controls. There was no association between EBNA1 titres and MS. High EBNA1 titre (>99.75U/l) was significantly associated with HLA DRBI*15:01 (OR=4.92. CI=1.07-22.57) status in MSers but not in healthy controls (OR=1.19, CI=0.53-2.63).
CONCLUSION: Evidence for a strong association with remote EBV infection was lacking in this study of Indian MSers. MSers who are carriers of HLA DR15 allele may have high EBNA1 titres. These preliminary results need to be reproduced in an independent and larger dataset.
"We have recently shown that ELISA is not the best method for asssessing EBV serostatus; the more sensitive microimmunofluorescence (MIF) assay is. This study therefore needs to be repeated."
"What is interesting is the association between HLA DRB1*15:01, the major MS risk gene, and EBV titres. This observation needs exploring further. It is clear that EBV and MS are strongly associated, the question is how?"