OBJECTIVE: To understand T cell role in the immunopathogenesis of rheumatoid arthritis(RA), authors investigated Vbeta usage of T cell receptor(TCR) in different onset RA lesion of the same patient using a reverse transcriptase-polymerase chain reaction. The current pathogenic model of RA plays a critical role in CD4+ T cells, which are thought to be able to recognize a disease-relevant antigen in the joint. In this model, activation of a certain, specific, antigen induced T cells plays a pivotal role in the development and maintenance of chronic inflammation. To search a common clone in different onset of inflammatory joints will furnish the most exact information about T cells which play a role at initiation and perpetuation of synovitis. Here, We first characterized the change in TCR Vbeta shape with elapsing time between the two joints that have the consecutive inflammation . METHODS: Synovial fluids and peripheral blood were obtained from a patient with active RA who had two successively developing inflammatory joints with 1 week interval(the right knee joint(RT) was involved first and the left knee joint(LT) later). RT-PCR technology was employed to examine synovial fluid and peripheral T cells. Oligonucleotide primers specific for individual TCR Vbeta gene families were used to amplify the TCR gene products in a semiquantitative assay of their relative utilization in fresh T cells subpopulations(CD4+, CD8+ T cells). RESULTS: The CD4+ T cells with TCR Vbeta 1(LT: 4.78%, RT: 2.17%), Vbeta 2(LT: 5.84%, RT: 0. 63%), Vbeta 5.1 (LT: 3.40%, RT: 1. 07%), Vbeta 5. 2 (LT: l. 91%, RT: 0. 31%), Vbeta 8(LT: 4. 20%,RT: 0. 19%), Vbeta 9(LT: 2. 61%, RT: 0. 12beta), Vbeta 10(LT: 4. 08%, RT: l. 27%), Vbeta 12(LT: 4. 53%, RT: 0. 99%), Vbeta 22 (LT: 3. 85%, RT: 0. 38%), Vbeta 23(LT: 3. 99%, RT: 0. 63%) were used more predominantly in the left knee joint than in the right knee joint while Vbeta 15 and 18 were used far more in the right knee joint. The CD8+ T cells were used less frequently in the left side than in the right side except the Vbeta 3, 4 and 7 families. CONCLUSIONS: Among the CD4+ T cells, TCR Vbeta 1, 2, 5. 1, 5. 2, 8, 9, 10, 12, 22, 23 families might play a key role in early symptomatic synovitis in RA. The role of TCR Vbeta 15 and 18 families increase in progressing synovitis with time. On the other hand, the late recruitment of CD8+ T cells in the inflamed site might be related to nonspecific inflammatory reaction.