Immune responses to Epstein-Barr virus in individuals with systemic and organ specific autoimmune disorders

Autoimmune diseases usually manifest in genetically predisposed individuals following an environmental trigger. There are several viral infections including Epstein-Barr virus (EBV) implicated in the pathogenesis of autoimmune disorders. The aim of this study was to look at the antibody pattern to EBV proteins in the plasma of both systemic and organ specific autoimmune disorders, estimate pro-inflammatory plasma cytokines (IL-8 and TNF-alpha) among these autoimmune patients and compare the observations with those in normal healthy controls.

Samples from 44 rheumatoid arthritis patients, 25 Hashimoto's thyroiditis patients, appropriately age and sex matched healthy controls were tested for EBV IgM antibodies by an immunoblot assay and two cytokines (IL-8 and TNF-alpha) by commercial assays.

Among the rheumatoid arthritis patients, 23 (52%) were positive for EBNA1 antibody, while 13 (52%) of the Hashimoto's thyroiditis patients and 12 (30%) of the healthy controls showed similar bands. The intensity of the bands was high in the autoimmune patients when compared to the bands seen in control samples. The difference in the EBNA1 reactivity between rheumatoid arthritis patients and controls were significant (P = 0.038). There was a significant difference in the IgM reactivity to VCAp19 protein between patients and controls (P = 0.011).

Our study showed an increased EBV activation among the autoimmune patient groups compared to the normal healthy controls. Further studies are required to delineate the association between the aetiology of autoimmune disorders and EBV.