Evidence for activated peripheral blood T-cells in rheumatoid arthritis.

We have previously demonstrated defective antigen specific T-suppressor (Ts) cell function in the peripheral blood lymphocytes (PBL) from patients with rheumatoid arthritis (RA). Our study was designed to delineate whether diminished Ts activity is due to impaired interleukin (IL) dependent clonal expansion of Ts cells or to prior in vivo activation. Patients with recent onset of RA, or a disease flare, exhibited enhanced IL generation (IL-1 and /or IL-2). Increased proportions of active E-rosettes, elevated spontaneous production of IgM, and total immunoglobulin in mitogen free cultures were consistent with the concept of prior lymphocyte activation in vivo. Our results do not support defective clonal expansion of Ts cells as the basis of deficient IL generation, but do support the concept of in vivo activation of PBM cells in some patients with RA.