Fig. 3

a-b The proliferative ability of OA and RA FLS was evaluated by CCK-8 assay and Ki-67 staining. c PCNA staining in OA and RA synovial tissues further validated that the percent of infiltrated PCNA⁺ cells was higher in RA synovial tissues compared to OA tissues. d RA FLS showed a more aggressive migrating feature when compared to OA FLS. e Expression of inflammatory genes, IL-1, IL-6, TNF-α and CCL2, are more highly expressed in RA FLS than in OA FLS. f Two pro-inflammatory cytokines, IL-6 and TNF-α, were significantly up-regulated in cell culture supernatant from RA FLS. Each bar in the figure represents the mean ± SEM of triplicates. *P < 0.05 and ** P < 0.01