Persistent synovial lymphocyte responses to cytomegalovirus antigen in some patients with rheumatoid arthritis

Synovial lymphocytes from 6 of 40 patients with rheumatoid arthritis responded to cytomegalovirus antigen stimulation. 3H-thymidine uptakes were more than 3 times greater than were those of the responses to 13 other microbial antigens. Similar results were obtained in 1 patient on 7 occasions over 17 months, and in the 5 other patients on each of 2 occasions. In 3 of the 6 patients, synovial lymphocyte responses to cytomegalovirus antigen were markedly different from simultaneous peripheral blood lymphocyte responses.