Fig. 4

Immunohistochemistry of IL-1β (a-d) and TNF-α (e-h) in the knee joints taken from vehicle control mice (a and e), AIA model mice (b and f) and AIA mice after receiving repeated i.g. of 0.4 g/kg CIE (c and g) and 0.8 g/kg CIE (d and h) for 28 days. Magnification × 200. Tissues from three different mice in each group and 10 randomly selected areas from each slide were analyzed. Quantitative data (Mean ± S.D.) are presented using the average density values of the IL-1β and TNF-α positive regions. ^** p < 0.01 compared with the vehicle control group; ^## p < 0.01 compared with the AIA model group