Fig. 5

The absence of S100A9 does not ameliorate cartilage and bone erosion in 20-week-old Il1rn^−/− mice. Representative photomicrographs of Safranin-O/Fast Green-stained sections showing cartilage and bone erosion in the ankle joints of 20-week-old S100a9^−/−, Il1rn^−/−, and Il1rn^−/−XS100a9^−/− mice (A, original magnification ×200 and B, original magnification ×100). Quantification of cartilage erosion at the tibia, proximal and distal sides of the talus, and proximal side of the navicular bone with an arbitrary score showed no significant differences between Il1rn^−/−XS100a9^−/− and Il1rn^−/− mice (C). No significant differences in bone erosion were observed between Il1rn^−/−XS100a9^−/− and Il1rn^−/− mice as quantified at 8 locations along the tibia, talus, and navicular bone (D). Scatterplots are shown, with horizontal and vertical lines representing mean ± SEM values. Each data point represents the sum score of the right and left ankle joints of one mouse. ns not significant, ***P < 0.001