Figure 2

Effect of soluble Fas ligand (sFasL) on vascular endothelial growth factor (VEGF)₁₆₅ production by synovial fibroblasts. (a) Fibroblast-like synoviocytes (FLSs) were cultured in triplicate for 24 hours with medium alone and transforming growth factor (TGF)-β (10 ng/ml) in the presence of various concentrations of sFasL (10 to 100 ng/ml). The amount of VEGF₁₆₅ in the culture supernatants was determined by ELISA. Data are the mean ± standard deviation (SD) of three independent experiments in triplicate. *P < 0.05; ^†P < 0.01 versus the cells stimulated with medium alone or TGF-β in the absence of sFasL. (b) The rheumatoid arthritis FLSs (RAFLS; n = 7) or osteoarthritis FLSs (OAFLS; n = 5) were treated with increasing concentrations of sFasL (1 to 100 ng/ml) in the absence or presence of 1% FCS for 24 hours. The viability of FLS was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Data are expressed as the mean ± SD. *P < 0.01 versus OAFLS.