Novel mechanisms of selective apoptosis in synovial T cells of patients with rheumatoid arthritis

J Rheumatol. 1996 Aug;23(8):1332-7.


Objective: To analyze whether T cells infiltrating the synovium of patients with rheumatoid arthritis (RA) express functional Fas antigen.

Methods: Mononuclear T cells, mainly from synovial tissues, synovial fluids (SF), and peripheral blood mononuclear cells (PBMC) from 14 patients with RA and 5 with osteoarthritis (OA), were treated with anti-Fas monoclonal antibody (Mab) (CH11) for 24 h in vitro. Cell viability and DNA fragmentation were examined. The expression of Fas antigen, Fas ligand, and T cell subpopulations was examined using flow cytometry and reverse transcription polymerase chain reaction.

Results: More than 50% of T cells from synovial tissue and SF of patients with RA underwent apoptosis, whereas no effect was observed in PBMC from RA or PBMC and synovial T cells from OA, suggesting that functional Fas antigens are specifically expressed on synovial T cells. Flow cytometric analysis demonstrated higher expression of Fas antigen in T cells from RA synovium than from PBMC. The T cell subpopulations susceptible to anti-Fas Mab were mainly CD45RO+ and CD4 or CD8 single positive T cells, indicating that activated mature T cells express functional Fas antigen. Fas ligand was overexpressed only in synovial nonadherent cells in RA at the level of mRNA, whereas T cells account for more than 60% of the total, but not in OA.

Conclusion: These findings suggest the majority of activated T cells infiltrating the synovium express functional Fas antigen and Fas ligand specifically in patients with RA but not OA. This phenomenon may provide a clue to understanding the pathogenesis of RA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antibodies, Monoclonal / pharmacology
  • Apoptosis / immunology*
  • Arthritis, Rheumatoid / immunology*
  • Base Sequence
  • Blotting, Southern
  • Humans
  • Leukocytes, Mononuclear / immunology
  • Middle Aged
  • Osteoarthritis / immunology
  • Polymerase Chain Reaction
  • Synovial Fluid / immunology*
  • Synovial Membrane / immunology*
  • T-Lymphocyte Subsets / immunology
  • T-Lymphocytes / immunology*
  • fas Receptor / analysis*


  • Antibodies, Monoclonal
  • fas Receptor