The relationship between Epstein-Barr virus（EBV）and rheumatoid arthritis

The levels of antibodies to EBV capsule antigen（EBV-VCA）were determined in 132 sera and 72 synovial fluids（SF）with indirect immunofluorescent method.The average of geometrical titres of EBV-VCA-IgG antibody in sera and SF was 1:150（69 sera）and 1:46（28 SF）respectively in RA,1:30（18 sera）and 1:2（33 SF）respectively in other joint disorders,as well as 1:32（45 sera）and 1:2（11 SF）respectively in normal controls.The frequencies of positive EBV-VCA-IgG antibody in immune complexes were 42.6 percent in sera and 50 percent in SF.The positive frequency of EBV-VCA-IgG antibody in seropositive RA（76%）was remarkablely higher than that in seronegative RA（26%）.The results suggest that high levels of anti-EBV antibody and auto-antibody were produced in RA patients after EBV infection,and that EBV-anti-EBV antigen-antibody system might involve in the formation of IC in RA and might play a role in the pathogenesis of RA.