Skewed T-cell receptor variable gene usage in the synovium of early and chronic rheumatoid arthritis patients and persistence of clonally expanded T cells in a chronic patient

Objective. Autoreactive T cells may contribute to the pathogenesis of rheum atoid arthritis (RA). We studied the T-cell receptor (TCR) V-gene repertoir e in the blood and synovium of early and chronic RA patients using polymera se chain reaction-enzyme-linked immunosorbent assay to evaluate possible di fferences between these patient groups. Results. Over-represented TCR V genes were observed in the synovium, but no t in the blood of all RA patients (n = 38). The number of over-represented V genes was higher in the synovium of chronic RA patients (n = 31) than in that of early RA patients (n = 7). The V-gene profile was different among p atients, and similar in the two knees for patients with bilateral synovitis (n = 5). The clonal composition of over-represented TCR BV genes in a pati ent with early RA and a patient with chronic RA was further studied by CDR3 region sequence analysis. A high level of clonal diversity was found in th e joints and the blood of the early RA patient, suggesting a polyclonal T-c ell expansion. In the chronic RA patient, predominant clonal expansions wer e observed in the blood and synovium, and some expanded clones were still p resent 2 yr later. Conclusions. The observation of similar T-cell populations in both joints i n patients with bilateral synovitis and the persistence of clonally expande d T cells for more than 2 yr in the joints of a chronic RA patient may indi cate a pathogenic role for these cells in the disease process.