Figure 2. L-PGDS deficiency enhanced MMP-13 and ADAMTS-5 expression in cartilage with age. Knee joint sections from 3- (n=6 mice per genotype) and 9-month-old mice (n=6 mice per genotype) were analyzed by immunohistochemistry for MMP-13 and ADAMTS5 as described in the Materials and Methods section. (A) Representative images of immunohistochemical staining for ADAMTS5, and MMP-13 in knee joints from L-PGDS-/- and their WT littermates at 3 and 9 months of age. Scale bars=100 μm. (B) Percentage of chondrocytes expressing ADAMTS5, and MMP-13 in WT (open symbols) and L-PGDS-/- (filled symbols) mice. Data are presented as median with interquartile range of each group. *p<0.05 versus WT mice.