Telomerase activity in rheumatoid synovium correlates with the mononuclear cell infiltration level and disease aggressiveness of rheumatoid arthritis

Objective. To determine whether the presence of telomerase activity in synovial tissues could provide insights into the pathogenesis of rheumatoid arthritis (RA). Methods. Synovial tissue samples obtained from patients with RA or osteoarthritis (OA) were examined for telomerase activity using the telomeric repeat amplification protocol (TRAP). Results. Telomerase activity was detected in over half the RA synovial tissues (14/25, 56%) but in no OA synovial tissue samples (0/15). Telomerase activity was detected in the mononuclear cells isolated from telomerase-positive RA synovial tissue, but not in cultured adherent cells. In RA synovial tissue with positive telomerase activity mononuclear cell infiltration levels were increased (p < 0.001). In addition, patients with RA with positive telomerase activity had undergone joint operations at an earlier age (p = 0.030) and more often (p = 0.023) compared to those without telomerase activity. Conclusion. Telomerase activity in RA synovial tissue is likely derived from infiltrating mononuclear cells and may be involved in the pathogenesis of RA. Clinically, the presence of telomerase activity in RA may be an indicator of a more aggressive phenotype.