Consistent with this gene expression data, immunohistochemical (IHC) staining confirmed higher protein levels of MMP11 and MMP28 in the articular cartilage of T1DM mice compared with controls (Fig. 1E), suggesting that these enzymes may be responsible for the emerging OA phenotype observed in the T1DM group. This evidence concerns the gene MMP28 and type 1 diabetes mellitus.