POTENTIAL WITHDRAWAL OF RHEUMATOID SYNOVIUM BY THE INDUCTION OF APOPTOSIS USING A NOVEL IN-VIVO MODEL OF RHEUMATOID-ARTHRITIS

Objective. To investigate whether Fas-mediated apoptosis has potential as a new therapeutic strategy in rheumatoid arthritis (RA) by use of a novel model of RA in which human RA tissue is grafted into SCID mice . Methods. Fresh rheumatoid synovial tissue including joint cartilage was grafted subcutaneously into the backs of SCID mice. Six weeks afte r engraftment, anti-Fas monoclonal antibody was injected intraperitone ally, Time-related apoptotic changes caused by anti-Fas monoclonal ant ibody in grafted synovium were evaluated by nick end-labeling histoche mistry. Results, Thirty-six hours after the injection, diffuse apoptot ic changes were observed in the grafted synovia. Four weeks after the injection, rheumatoid synovial tissue diminished. Conclusion. This is the first report concerning the present effectiveness of anti-Fas mono clonal antibody in diminishing rheumatoid synovium in vivo, and sugges ts the possibility of a new strategy for treating rheumatoid arthritis by inducing Fas-mediated apoptosis.