IL1B and rheumatoid arthritis: LPS-induced macrophages (RAW264.7 cells), TNF-α-stimulated FLSs (MH7A cells) and IL-1β-stimulated primary RA FLSs; cells pre-treated with 16 (0, 1, 5, 10, 25 or 50 μM) for 1 h and incubated with 100 ng/mL LPS (RAW264.7 cells), 10 ng/mL TNF-α (MH7A cells) or 2.5 ng/mL IL-1β (RA FLSs) for 24 hCIA DBA/1 male mice; daily i.p. administration of 16 (2.5 or 5 mg/kg) or vehicle (saline, PEG400 and DMSO 6:3:1 v/v) or MTX (10 mg/kg), intragastrically, for 20 days