Fig. 3

CSR inhibited the JAK2/STAT3 pathway in IL-6/sIL-6R-stimulated RA-FLS. Cells were incubated with indicated concentrations of CSR for 1 h and then stimulated with IL-6/sIL-6R (100 ng/ml each) for 40 min. (a) Protein levels of JAK2, phospho-JAK2 (Tyr1007/1008), STAT3 and phospho-STAT3 (Tyr705). β-Actin served as the loading control. (b) Protein levels of STAT3 in cytoplasmic and nuclear extracts. GAPDH and lamin B1 served as loading controls of cytoplasmic and nuclear extracts, respectively. (c) Protein levels of Bcl-2 and Mcl-1. GAPDH served as the loading control. In (a) – (c), representative immunoblotting results are shown in left panels. Quantitative results are shown in right panels. Each membrane was cut based on molecular weights of proteins to be examined before hybridisation with primary antibodies. Original images of all blots are presented in Additional file 4. Data are expressed as mean ± SD of 3 independent experiments. * P < 0.05, ** P < 0.01 vs. IL-6/sIL-6R plus CSR solvent-treated group. ## P < 0.01 vs. solvents-treated group