Figure 1: Influence of IL-13 on periostin production from HFLS-OA in vitro. Human synoviocytes from an OA patient (HFLS-OA) at 1 x 10⁵ cells/ml were cultured with different concentrations of IL-13 for 24 to 72 h. Concentration of periostin in culture supernatants was measured by ELISA. The results were expressed as the mean ng/ml ± SE of triplicate cultures. A: Time course of IL-13-induced periostin production; B: Dose response profile of IL-13-induced periostin production; Med. alone: Medium alone. One representative experiment of two.