Cell-surface components Actinobacillus actinomycetemcomitans promote osteoclast formation in vitro

在小鼠器官培养和小鼠骨髓培养系统中研究了牙周病细菌放线菌细胞表面组分诱导破骨细胞骨吸收的机制。从放线菌y4中分离的脂多糖和荚膜多糖诱导c3h /HeN小鼠颅骨器官培养骨吸收。用放线菌y4荚膜多糖或脂多糖培养小鼠骨髓细胞9 d，可形成多核细胞。多核细胞表现出破骨细胞的几个特征，包括抗酒石酸磷酸酶的产生和钙化牙本质的再吸收能力，在本研究中，单特异性抗小鼠重组白细胞介素- 1 α血清和吲哚美辛完全抑制了a.c ray omycetem comitans y4荚膜多糖存在下破骨细胞的形成。IL-1受体拮抗剂显著抑制小鼠骨髓培养中破骨细胞的形成。用放线菌y4荚膜多糖刺激小鼠骨髓细胞培养上清液检测生物活性IL-1。这些结果表明，IL-1参与了a.c ray omycetemcomitans y4荚膜多糖诱导破骨细胞样细胞形成的机制。小鼠骨髓培养中形成的破骨细胞数量与前列腺素E_2释放到培养基中的量也有良好的相关性。这些结果提示放线菌荚膜多糖可能通过促进破骨细胞的形成在牙周病炎症性骨吸收中起重要作用。

The mechanism of osteoclastic bone resorption induced by periodontopathic bacteria Actinobacillus actinomycetemcomitans cell-surface components was investigated in mouse organ cultures and in a mouse bone marrow culture system. Lipopolysaccharide and capsular polysaccharide isolated from A.actinomycetemcomitans Y 4 induced bone resorption in C 3 H/HeN mouse calvarium organ culture. Many multinucleated cells were formed when mouse bone marrow cells were cultured with A.actinomycetemcomitans Y 4 capsular polysaccharide or lipopolysaccharide for 9 days. The multinucleated cells showed several characteristics of osteoclasts, the production of including tartrateresistant acid phosphatase and the ability to resorb calcified dentine, in this study, monospecific antimouse recombinant interleukin-l alpha serum and indomethacin completely inhibited the formation of osteoclasts in the presence of A.actinomycetem comitans Y 4 capsular polysaccharide. An IL-1 receptor antagonist significantly inhibited the osteo clast formation in mouse marrow cultures. Bioactive IL-1 was detected in the culture supernatant of mouse bone marrow cells stimulated with A.actinomycetemcomitans Y 4 capsular polysaccharide. These results indicate that IL-1 alpha is involved in the mechanism of formation of osteoclast-like cells induced by A.actinomycetemcomitans Y 4 capsular polysaccharide. There was also a good correlation between the number of osteoclasts formed in the mouse marrow culture and the amount of prostaglandin E_2 released into the culture medium. These findings suggest that A.actinomycetemcomitans capsular polysaccharide may play an important role in inflammatory bone resorption by promoting osteoclast formation in periodontal diseases.