Ia+ T Cells in Synovial Fluid And Tissues of Patients with Rheumatoid Arthritis

Abstract
Markedly elevated levels of T cells expressing Ia antigens were found in the synovial membranes and synovial fluids of patients with rheumatoid arthritis. The primary increase in expression of the la antigens was on the OKT 8+ (suppressor/cytotoxic) T cell subset. In addition, the total percentage of OKT 8+ T cells in intraarticular sites was usually greater than levels in peripheral blood. Small numbers of OKT 4+ (helper/inducer) cells bearing la antigens were also identified. The characteristic increase in the Ia+ T cells in peripheral blood was not encountered in most patients treated with D-penicillamine.