Characterisation of T cell clonotypes that accumulated in multiple joints of patients with rheumatoid arthritis

Abstract

Objective: To investigate whether identical T cell clonotypes accumulate in multiple rheumatoid joints, the clonality of T cells that had infiltrated into synovial tissue (ST) samples simultaneously obtained from multiple joints of patients with rheumatoid arthritis (RA) was analysed.

Methods: T cell receptor (TCR) beta gene transcripts, amplified by reverse transcription-polymerase chain reaction from ST and peripheral blood lymphocytes of five RA patients, were subjected to single strand conformation polymorphism analysis and DNA sequencing.

Results: Approximately 40% of accumulated T cell clonotypes found in one joint of a patient were found in multiple joints in the same patient. Furthermore, identical amino acid sequences were found in TCR beta junctional regions of these clonotypes from different patients with at least one HLA molecule match.

Conclusions: The T cell clonotypes accumulating in multiple rheumatoid joints may be involved in the perpetuation of polyarthritis by reacting to antigens common to these multiple joints.

Figure 1

Comparison of accumulated TCR β gene clonotypes in different joints by RT-PCR/SSCP analysis. ST specimens were derived from four different joints of RA1 and two different joints of RA2-RA5, respectively. TCR β gene transcripts, amplified from each specimen by RT-PCR, were separated based on their single strand conformation polymorphism on a single gel to detect TCR β gene bands with identical migrating positions. Some of the distinct TCR β gene bands derived from different specimens were found to migrate to identical positions (indicated by asterisks). This indicates that T cells that possessed TCR β gene transcripts corresponding to these bands accumulated clonally in multiple joints. Results of representative three BV families (BV3, BV5S2 and BV14) are shown. Arrows indicate bands from which TCR β gene transcripts were recovered for determination of nucleotide sequences. The results of RA1 are shown as follows: (lane 1, PBLs; lane 2, ST from the left ankle; lane 3, ST from the right ankle; lane 4, ST from the left PIP; and lane 5, ST from the left elbow). The results of RA2-RA5 are shown as follows: RA2: lane 1, PBL; lane 2, ST from the right MP; lane 3, ST from the right knee. Similarly, RA3: lane 1, PBL; lane 2, ST from the right MP; lane 3, ST from the right elbow. RA4: lane 1, PBL; lane 2, ST from the right wrist; lane 3, ST from the left knee. RA5: lane 1, PBL; lane 2, ST from the right knee; lane 3, ST from the left knee.