Autologous and allogeneic MLC-reactivity in patients with rheumatoid arthritis

In vitro interaction of autologous peripheral blood and synovial fluid lymphocytes was studied using isolated lymphocytes from 15 patients with rheumatoid arthritis. In the applied one way mixed lymphocyte cultures (MLC) a significant proliferative response was obtained when peripheral blood lymphocytes were cultured with mitomycin treated synovial fluid cells. In contrast, when the reverse situation was examined, only a marginal stimulation of synovial fluid lymphocytes by peripheral blood lymphocytes was recorded. Studies on the effect of macrophage depletion on the autologous MLC made in unlikely that the decreased proliferative response of SFL was due to the presence of a monocyte suppressor cell population in SFL. Likewise no evidence could be obtained that the decreased MLC response of SFL to autologous and allogeneic lymphocytes was caused by the predominance of short lived T-suppressor cells in the synovial fluid.