Immunological Characterization of Lymphocytes in Synovial Fluid from Patients with Rheumatoid Arthritis

Abstract

Lymphocytes separated from synovial fluid in rheumatoid arthritis by means of gradient centrifugation were characterized with regard to B‐ and T‐lymphocyte properties. Membrane‐bound Ig detectable with immunofluorescence technique was utilized as a marker of B‐lymphocytes, while the ability to bind sheep erythrocytes and form rosettes was interpreted as a T‐lymphocyte characteristic. In 9 out of 18 patients studied no Ig‐positive lymphocytes were found in synovial fluid, while the remaining 9 patients had 1% or less. Appropriate control experiments indicated that the absence of membrane‐bound Ig on lymphocytes was not due to in vivo induced redistribution with subsequent endocytosis of Ig receptors. The percentages of B‐lymphocytes in peripheral blood from patients (mean 11% and range 3–19%) were not significantly different from those of 54 normal individuals (mean 10% and range 3–22%). Rosette‐forming lymphocytes were found in synovial fluid of 11 patients studied, with mean 29.6% and range 19.0–60.2%, which are significantly higher than the corresponding values in peripheral blood, 22.7% and 0.9–41.1%. The latter values were also significantly higher than those of peripheral blood from 32 normals (mean 14.8% and range 0.9–34.7%). The increased proportions of T‐lymphocytes in synovial fluid in rheumatoid arthritis in contrast to the absence or very low numbers of B‐lymphocytes may indicate an important role for the former in the pathogenesis of rheumatoid inflammation.

Synovial fluid lymphocytes in rheumatoid arthritis

“…Froland et a1 recorded a significant increase i n percentages of T cells and a virtual absence of B-cell populations versus peripheral blood lymphocytes (48). Mellbye et a1 observed increased percentages of B cells in rheumatoid synovial fluids (49).…”

Clinical aspects of T‐ and B‐lymphocytes in rheumatic diseases

“…This phenomenon suggests caution in using C3 rosettes as the sole marker for B-cells in pathologic conditions. In contrast, Froland et a1 (28) found a sharp decrease in B-cells by surface immunoglobulin. They also noted an increase in T-cells by E-binding compared to peripheral blood.…”

Gold-specific T cells in rheumatoid arthritis patients treated with gold.

“…The presence of lymphocytic infiltrates (1,2) and the association of the disease with specific MHC class II determinants (reviewed in 3), which control antigen presentation to T cells, suggest that autoreactive T lymphocytes may initiate and/or -maintain the inflammatory process.…”