DETECTION OF T-CELL RECEPTORS IN EARLY RHEUMATOID-ARTHRITIS SYNOVIAL TISSUE

Synovial tissue is rarely available from patients with early synovitis , with the exception of synovial biopsies, However, T cell populations early in the development of synovitis may be enriched in antigen-spec ific cells and critical to disease pathogenesis, To investigate the T cell repertoire in early synovitis, we utilized a PCR protocol for det ection of T cell receptor (TCR) transcripts present in small amounts o f synovial tissue. To expand the substrate for PCR, preamplification o f cDNA was performed with a 3' constant region primer plus either a mi xture of variable region primers or random hexanucleotides. Utilizing this method improved the sensitivity of detection, This technique is a pplied here to the analysis of TCR transcripts in synovial biopsies fr om individuals with early rheumatoid arthritis (RA) and non-RA synovit is, TCR alpha-chain transcripts were detectable in 5/5 RA and 4/4 non- RA specimens evaluated, with beta-chain transcripts detected in 4/5 ea rly RA and 4/4 non-RA specimens evaluated, Confirmation of transcripts by sequencing of cloned PCR products verfied the specificity of ampli fication. The most frequently expressed TCR V region families in early RA synovitis were V alpha 11, V alpha 14, V alpha 28, V beta 7, V bet a 9 and V beta 17. Several of these V regions have previously been imp licated in studies of chronic RA synovitis, J alpha and J beta region usage was similar to that seen in chronic RA, and conserved N region m otifs were apparent. We Early arthritis conclude that it is possible t o detect TCR transcripts in small synovial biopsies Synovial tissue fr om individuals with early arthritis, This technique can be applied to studies Synovial biopsy of synovitis where limited quantities of synov ial tissue are available.