Fig. 4

Postn^−/− mice expressed less MMP-13 than wt mice after DMM. a Immunofluorescent analysis showed that MMP-13 staining (green) was higher in cartilage of DMM-operated limbs than in the non-operated control limb. Postn^−/− mice (n = 4) showed less staining of MMP-13 than wt mice (n = 4). Type II collagen (Col 2) (red) staining was used for location of cartilage. The dotted lines on lower panels indicate the Col 2-positive cartilage area based on the results in the upper panels. DAPI (blue) was used as a counterstain. Scale bars = 100 μm. b Quantification of immunostaining intensity of MMP-13 showed that MMP-13 intensity was significantly lower in Postn^−/− mice (n = 4) than wt mice (n = 4). (Mann-Whitney test)