Fig. 3.

Expression of retinoic acid-inducible gene-I (RIG-I) and fibroblast-specific protein-1 in cultured human fibroblast-like synoviocytes. Fibroblast-like synoviocytes obtained from patients with osteoarthritis or rheumatoid arthritis were cultured and treated with 2 ng/ml interferon (IFN)-γ for 4 h, and reverse transcription–polymerase chain reaction (RT–PCR) was performed (a). Cultured fibroblast-like synoviocytes were treated with various concentrations of IFN-γ for 24 h, and the expression of RIG-I mRNA or protein was examined by RT–PCR (b) or Western blot analysis (c). The cells were treated with 2 ng/ml IFN-γ for up to 24 h, and RT–PCR (d) and Western blot analyses (e) were performed.