HIGH-CONCENTRATIONS OF IMMUNOREACTIVE GLIOSTATIN PLATELET-DERIVED ENDOTHELIAL-CELL GROWTH-FACTOR IN SYNOVIAL-FLUID AND SERUM OF RHEUMATOID-ARTHRITIS

Since neovascularization plays an important role in the propagation of rheumatoid synovitis, we analyzed the concentration of gliostatin/pla telet-derived endothelial cell growth factor (GLS/PD-ECGF), a potent a ngiogenic and chemotactic factor, in the synovial fluid and serum of r heumatoid arthritis (RA) patients. The immunoreactive GLS/PD-ECGF conc entrations (mean value +/- S.D.) in synovial fluid, measured by a sand wich enzyme immunoassay, were significantly higher in RA patients than in osteoarthritis (OA) patients (233.02 +/- 219.40 vs. 9.09 +/- 14.86 ng/g, P < 0.001), and the serum concentrations were also higher in RA patients than in age-matched controls (8.77 +/- 7.60 vs. 3.74 +/- 2.6 1 ng/ml, P < 0.005). These results suggest that GLS/PD-ECGF may partic ipate in the endothelial proliferation resulting in initiation of the extensive emigration of mononuclear cells and proliferation of the syn ovial tissues in rheumatoid arthritis, and that the immunoreactive GLS /PD-ECGF in serum as well as synovial fluids may be a useful diagnosti c marker of RA.