Cellular and humoral immune parameters of synovial fluid and blood in rheumatoid arthritis.

Thymus derived (T) and bone marrow derived (B) cells from joint fluid and peripheral blood of 15 patients with rheumatoid arthritis and 10 controls with other inflammatory joint diseases were studied. High absolute numbers and high percentages of T cells in the synovial fluid, T plus B cell sums exceeding 100 per cent in synovial fluid or blood, and fewer complement receptors compared to surface Ig bearing cells in joint fluid or blood was found only in rheumatoid arthritis. T and B cell numbers did not correlate with disease activity. No differences in T and B cells were found between patients positive or negative for rheumatoid factor. (J Rheumatol 2: 363-372, 1975).