T-CELL RECEPTOR DIVERSITY AND ACTIVATION MARKERS IN THE V-DELTA-1 SUBSET OF RHEUMATOID SYNOVIAL-FLUID AND PERIPHERAL-BLOOD LYMPHOCYTES-T

In the present study we have characterized the gamma/delta T cell receptor (TcR) population in synovial fluid (SF) and peripheral blood (PB) of patients with chronic inflammatory arthritis. By double staining we have shown that (a) synovial V(delta)1+ cells have a high expression of activation markers CD45R0 ("memory cells") and HLA-DR as compared to PB, indicating a preactivated population of V(delta)1-carrying T cells in vivo and (b) interleukin 2-induced expansion of synovial cells yields a high proportion of gamma/delta in most samples expressing predominantly the V(delta)1 TcR. Junctional sequence analysis of the TcR delta-chain from interleukin 2-expanded PB cell lines demonstrated a polyclonal V(delta)1 population in three out of three samples. In SF cell lines three out of four samples were polyclonally expanded. In SF from one patient, however, a limited repertoire of expressed V(delta)1 genes was found. Altogether, our data demonstrate the presence of preactivated V(delta)1-expressing cells in the synovial compartment. This V(delta)1 population is predominantly polyclonal, except in one patient where oligoclonally expanded V(delta)1 cells were detected.