A comparison of Epstein-Barr virus-specific T-cell immunity in rheumatoid arthritis and osteoarthritis patients.

The level of Epstein-Barr virus (EBV)-specific T-cell-mediated immunity in 20 rheumatoid arthritis (RA) patients was compared with 16 age- and sex-matched osteoarthritis (OA) patients using the regression of EBV-transformation assay. The results show that the level of EBV-specific T-cell immunity in RA patients is significantly depressed compared with OA patients (P less than .001) or healthy laboratory controls (P less than .001). In contrast, lymphocytes from RA and OA patients showed a similar ability to act as a responder population in the mixed leucocyte reaction. It is unlikely that the difference in EBV-specific immunity is due to a general T-cell defect in RA patients since there was no correlation between EBV-specific T-cell immunity and mixed leucocyte reactivity. There was no correlation between EBV-specific T-cell immunity and any of the indicators of disease activity nor was there any difference in the anti-EBV antibody titre between both groups of patients. These results indicate that RA patients are deficient in the EBV-specific cytotoxic T-cell precursor population and may explain some of the reported observations of the involvement of EBV in this disease.