T cell receptor diversity and activation markers in the Val subset of rheumatoid synovial fluid and peripheral blood T lymphocytes"
In the present study we have characterized the $6 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 Vsl+ cells have a high expression of activation markers CD45RO ("memory cells") and HLA-DR as compared to PB, indicating a preactivated population of VJ-carrying T cells in vivo and (b) interleukin 2-induced expansion of synovial cells yields a high proportion of y/6 in most samples expressing predominantly theVbl TcR. Junctional sequence analysis of theTcR 6 chain from interleukin 2-expanded PB cell lines demonstrated a polyclonal Vbl 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 V61 genes was found. Altogether, our data demonstrate the presence of preactivated VJ-expressing cells in the synovial compartment. This V61 population is predominantly polyclonal, except in one patient where oligoclonally expanded Val cells were detected.