Fig. 3

Immunomodulatory effects of LAP on collagen-induced arthritis (CIA). DBA1/J male mice were injected i.d. at the base of the tail with 200 μg CII emulsified in CFA on day 0. Mice were boosted i.d. with CII (200 μg emulsified in IFA) on day 21. After arthritis induction, mice were treated orally with lapachol (Lap) (3 mg/kg and 10 mg/kg) or leflunomide (Lef) (3 mg/kg) or saline daily. a Clinical score/mouse (left panel) and affected paws/mouse (right panel) were addressed daily after arthritis induction. Data represent mean, n = 5 mice per group. *P < 0.05, **P < 0.01, ***P < 0.001. b, c Histological analysis of CIA mice treated with LAP (3 mg/kg and 10 mg/kg) or LEF (3 mg/kg). Representative images of knee joint sections stained with H&E (b) or Safranin-O (c) and respective histopathological scores. Magnification for H&E: upper row 100×; lower row 400×; Safranin-O: upper row in 100×; lower row in 250×. Data represent mean, n = 5 in the vehicle and naive groups, n = 4 in Lef, Lap3 and Lap10 groups. *P < 0.05, **P < 0.01. Production of interferon gamma (IFN-γ) (d) and interleukin-17A (IL-17A) (e) tissue levels from paws of CIA mice at 4 weeks after the boost with CII. f Myeloperoxidase (MPO) activity from paws of CIA mice at 4 weeks after the boost with CII. Data represent mean ± SEM, n = 5 mice per group. *P < 0.05, **P < 0.01