The Adhesion molecule expression in osteoclastic differentiating process

本研究旨在揭示体内体外破骨细胞分化过程中粘附分子在破骨细胞表面的表达情况。用成骨细胞与骨髓细胞共培养液培养骨髓细胞，分别于1、3、5 d分化为贴壁细胞和非贴壁细胞。流式细胞术（FACS）分析培养的骨髓细胞表面抗原（Mac-1、LFA-1、cd44和Mel 14），并于培养第14天对培养的骨髓细胞进行酒石酸抗性酸性磷酸酶（TRAP）染色。采用免疫组化染色法观察小鼠牙周组织中粘附分子（Mac-1、LFA-1、ICAM-1）的表达情况。在体外实验中，破骨细胞的粘附分子（Mac-1、LFA-1、ICAM-1）在共培养液培养的骨髓细胞中转化为弱于巨噬细胞的表达。在体内实验中，在小鼠牙周韧带内部和骨髓间隙均可识别出Mac-1和LFA-1阳性细胞。ICAM-1阳性细胞主要分布在牙根尖部和骨髓间隙周围。而在正畸力作用下，牙槽骨受压侧破骨细胞数量和粘附分子阳性细胞数量均显著增加。这些结果提示，粘附分子的表达与破骨细胞分化之间的关系对造血干细胞破骨细胞的成熟过程具有重要意义。

The purpose of this investigation was to reveal the expressions of adhesion molecules on the surface of osteoclast during osteoclastic differentiation in vivo and in vitro. Bone marrow cells were cultured with the co-culture fluid of osteoblasts and bone marrow cells and divided to adherent cells and non adherent cells at 1,3,5 days.Surface antigens (Mac-1,LFA-1,CD 44 and Mel 14) of the cultured bone marrow cells were analyzed by Flow cytometry (FACS) and also the cultured bone marrow cells were stained with tartrate resistent acid phosphatase (TRAP) on 14 days culture. In order to evaluate the expressions of adhesion molecules (Mac-1,LFA-1,ICAM-1) in peridontal tissues of mice, immunohistochemical staining in vivo were made.The following results were obtained:In vitro experiments,adhesion molecules (Mac-1,LFA-1,ICAM-1) of osteoclasts converted to weaker expression than that of macrophages in bone marrow cells cultured with the coculture fluid. And then in vivo experiments, Mac-1 and LFA-1 positive cells could be recognizes in the inside of periodontal ligaments and the marrow spaces of mice. ICAM-1 positive cells were observed specifically around the apex of the tooth root and marrow spaces. However,when orthodontic force were applied to teeth, in compressed side of alveolar bone, both numbers of osteoclast and the adhesion molecule positive cells were significantly increased.These results suggested that the relationship between the expressions of adhesion molecules and the differentiation of osteoclasts was very important for the maturation process of osteoclast from hematopoietic stem cells.