IL-6 , matrix metalloproteinase ( MMP )- 3 and vascular endothelial growth factor ( VEGF ) in exosomes derived from IL-1β-stimulated synovial fibroblasts (SFB). The concentration of pro-inflammatory cytokines (IL-1β, IL-6, TNFα), angiogenic factor (VEGF) and cartilage degradation enzymes (MMPs) was measured in CM, exosomes, and CM-exo from IL-1β stimulated SFB using Bio-Plex assays. CM and CM-exo contained significant amounts of IL-6, VEGF and MMP-3. However, exosomes contained significantly lower IL-6, VEGF and MMP-3 levels than CM or CM-exo. Data are the means ± standard error of the mean. CM, conditioned medium; CM-exo, exosome-depleted conditioned medium; U Exo, exosome isolated by ultracentrifugation method; Q Exo, exosome isolated by ExoQuick™ reagent.