Fig 1. AEBS suppresses inflammatory arthritis in CIA mice.

Both the arthritis score and the incidence of arthritis were reduced in CIA mice given AEBS. Mice were immunized with CII. Seven days later, mice were given oral AEBS (60 mg/kg) or vehicle, daily, for 8 weeks. (A) The mean arthritis scores ± SDs (left panel) and arthritis incidence scores (right panel). (B) Histological data on joints from CIA mice given AEBS or vehicle. Mice were sacrificed on day 49 after immunization. Joint tissue sections were stained with H&E, toluidine blue, and safranin O. Joints from mice given AEBS exhibited mild erosive arthritis, whereas those from vehicle-treated mice exhibited markedly erosive destructive arthritis. Representative photographs are shown. Original magnifications ×40 or ×200, as indicated. The histological scores (measuring inflammation and the extent of cartilage damage) in mice given AEBS (n = 5) or vehicle (n = 5) are shown in the right graph. Data are expressed as means ± SDs. ***P < 0.01 compared to the vehicle-treated control group. (C) Tissue sections from joints of CIA mice given AEBS or vehicle were stained with anti-nitrotyrosine and anti-iNOS antibodies. Cells stained with either antibody are brown in color. Original magnification ×400. The cells showing positive nitrotyrosine, and iNOS were enumerated visually at higher magnification (projected on a screen) by four individuals, and the mean values are presented (cells/field). (D) Levels of total circulating IgG, IgG1, and IgG2a in CIA mice given AEBS (n = 8) or vehicle (n = 8). Total IgG, IgG1, and IgG2a levels were determined in sera of individual mice via ELISA. Data are expressed as means ± SDs. * P < 0.05, *** P < 0.001 compared to the vehicle-treated group. Each experiment was performed 3 times.