Figure 2

Arthritis and cartilage damage in the knee joint 14 days post intra-articular injection. (A-F) Representative histologic sections of knee joints from wild-type (WT) and transgenic mice (TG) treated with mBSA (AIA) and from non-arthritic wild-type control mice (CTR). Both inflammatory activity and cartilage damage were similar in transgenic mice and wild-type mice treated with mBSA. (A–C) Hematoxylin and eosin staining. Arrows show synovitis, joint space exudate and soft tissue inflammation. Bars = 100 μm. (D–F) Toluidine blue staining. Arrows show proteoglycan loss of articular cartilage. Bars = 100 μm. (G-H) Histopathology scores (G single, H total) in mBSA-treated mice (AIA) 14 days post injection. The knee joints of all mice were assessed as described in Materials and Methods. Bars show the mean ± SEM. Findings in arthritic wild-type AIA mice and arthritic transgenic AIA mice for single scores were compared by Mann–Whitney test. Total scores were compared between the 4 groups with adjustment for 4 parallel tests (α* = 0.0125). NS = not significant (see Figure 1 for other definitions).