Xie Rui, Kuijpers-Jagtman Anne M, Maltha Jaap C
Department of Orthodontics and Oral Biology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
Eur J Oral Sci. 2009 Feb;117(1):43-50. doi: 10.1111/j.1600-0722.2008.00588.x.
Osteoclasts are derived from macrophage-lineage precursors. ED1 is an antibody that can recognize this lineage of cells. Matrix metalloproteinase 9 (MMP9) is essential for the migration of osteoclasts and their precursors during osteoclastogenesis. The aim of this research was to investigate differentiation and recruitment of osteoclasts during the early phase of experimental tooth movement in rats. The upper three molars of Wistar rats at one side were moved mesially, using Ni-Ti coil springs of 10 cN, for 6, 12, 24, 36, 48, 72, 96, and 120 h. The contralateral sides served as controls. Immunohistochemical staining using ED1 and MMP9 antibodies was performed. ED1(+) and MMP9(+) mononuclear and multinuclear cells were counted and statistically analysed. After force application, the number of ED1(+)/MMP9(+) multinuclear cells first increased in the bone marrow. At compressed areas, the number of ED1(+) mononuclear cells decreased; this was followed by an increase in the number of ED1(+/)MMP9(+) mononuclear and multinuclear cells. At tension areas, the number of ED1(+)/MMP9(+) multinuclear cells decreased while the number of ED1(+) mononuclear cells remained stable. It was concluded that force application induces osteoclast differentiation within the bone marrow. These osteoclasts probably migrate subsequently into the compressed PDL. Pre-existing osteoclasts disappear at the tension areas while the number of mononuclear macrophage-lineage cells remains stable.
破骨细胞源自巨噬细胞系前体细胞。ED1是一种能够识别该细胞系的抗体。基质金属蛋白酶9（MMP9）对于破骨细胞及其前体细胞在破骨细胞生成过程中的迁移至关重要。本研究的目的是调查大鼠实验性牙齿移动早期破骨细胞的分化和募集情况。使用10 cN的镍钛螺旋弹簧将一侧Wistar大鼠的上三颗磨牙向近中移动6、12、24、36、48、72、96和120小时。对侧作为对照。使用ED1和MMP9抗体进行免疫组织化学染色。对ED1（+）和MMP9（+）单核及多核细胞进行计数并进行统计学分析。施加力后，骨髓中ED1（+）/MMP9（+）多核细胞数量首先增加。在压缩区域，ED1（+）单核细胞数量减少；随后ED1（+）/MMP9（+）单核及多核细胞数量增加。在张力区域，ED1（+）/MMP9（+）多核细胞数量减少，而ED1（+）单核细胞数量保持稳定。得出的结论是，施加力可诱导骨髓中的破骨细胞分化。这些破骨细胞随后可能迁移至压缩的牙周膜。张力区域中预先存在的破骨细胞消失，而单核巨噬细胞系细胞数量保持稳定。
