Figure 3: Influence of chondroitin sulfate (CS) on STAT6 activation after IL-13 stimulation in vitro. Human synoviocytes from an OA patient (HFLS-OA) at 1 x 10⁵ cells/ml were cultured with 10.0 ng/ml IL-13 for 12 h in the presence of various concentrations of CS. STAT6 activation was measured by ELISA and the results were expressed as the mean optical density at 450 nm ± SE of triplicate cultures. Med. alone: Medium alone. One representative experiment of two..