We evaluated the T cell receptor (TCR) V beta chain family expression in the peripheral blood lymphocytes from patients with rheumatoid arthritis, psoriatic arthritis and post traumatic synovitis. We used commercially available monoclonal antibodies and flow cytometry. No significant changes were observed in the percentages of the various TCR families when patients were compared to normal control. We also evaluated TCR families in paired samples from peripheral blood and synovial fluid of 6 patients. No synovial specific changes were documented. We conclude that by means of the available monoclonal antibodies, no mono, oligo-clonal T cell expansion can be detected in rheumatoid arthritis.