Contrary to the results of an earlier study published in January, samples of synovial tissue from rheumatoid arthritis patients tested positive for Epstein-Barr Virus, which researchers believe may influence the development of arthritic disease.
Synovial tissue surrounds the lining of the joints. The Japanese scientists removed samples of this membrane from 32 rheumatoid arthritis patients and 30 control patients with osteoarthritis. The samples were taken from various parts of the body including knees, elbow, shoulder and hips.
Not only was Epstein-Barr Virus (EPV) present in 15 of the 32 samples from rheumatoid arthritis patients, but the level of cells testing positive for the virus was more than 100 times higher than in people who normally test for EPV alone, demonstrating a high degree of infected cell replication.
The infected cells were present in lymphocytes (the main cells capable of providing the body with immune capability) and the synovial tissue. “There is an extremely high EPV load in the synovial tissue of rheumatoid arthritis patients,” the researchers concluded.
There was no indication of the virus’ presence in the samples taken from the osteoarthritis patients. Osteoarthritis is a much more common degenerative joint disease, whereas rheumatoid arthritis is a systemic autoimmune disease, potentially affecting the entire body and involving many different joints.
Source: Arthritis & Rheumatism, 2000