[P1-3-01] Immunohistochemical localization of MMP-9, MMP-13, and extracellular matrix proteins in the mandibular condyle of MMP-2-deficient mice
Keywords:MMP-2-deficient mice、Mandibular condyle、Immunohistochemistry
Mice lacking matrix metalloproteinase (MMP)-2 due to gene targeting exhibit cartilage destruction in the knee joint, but little is known about its effect on the mandibular condylar cartilage. In this study, the mandibular condyle of Mmp2−/− mice and wild-type (WT) mice were immunohistochemically examined for the localization of MMP-9, MMP-13, and extracellular matrix (ECM) proteins (type I and II collagen, and aggrecan). No cartilage destruction in the mandibular condyle of Mmp2−/− mice, and the localization of ECM proteins was similar to that of WT mice. However, the bone marrow cavity in the subchondral bone of the mandibular condyle was more prominent in Mmp2−/− mice at 50 weeks of age. Additionally, MMP-9 was specifically localized in multinucleated cells in the mandibular condyle of 50-week-old Mmp2−/− mice. These findings suggest that MMP-2 may play a role in regulating osteoclast differentiation and the formation of the bone marrow cavity in aged mice.