EphrinB2/EphB4信号介导的促红细胞生成素对骨重塑的作用及其机理研究

已知ephrinB2-EphB4相互作用通过正向和逆向信号调控成骨和破骨细胞的分化与功能。我们发现EPO能影响破骨和成骨细胞分化过程中某些关键分子的表达，并伴随细胞表面ephrinB2和EphB4表达的改变。为了证明EPO对骨重塑的作用是由ephrinB2/EphB4双向信号介导的，采用RT-PCR、Western blot和细胞化学等方法研究EPO对破骨和成骨细胞单独培养或共培养中ephrinB2/EphB4及其下游信号分子表达的影响，明确EPO对破骨和成骨细胞分化及功能的作用；通过基因功能激活和RNAi等技术验证EPO作用下ephrinB2/EphB4同破骨和成骨细胞相关分子表达的关系，阐明EPO通过ephrinB2/EphB4信号对骨重塑的作用及机理；采用Micro CT和免疫组织化学等技术，观察EPO对大鼠切牙拔除后剩余牙槽嵴骨再生的作用，为应用EPO治疗颌骨破坏性疾病奠定基础。

We know that interaction between ephrinB2 and EphB4 can regulate differentiation and function of osteoblast and osteoclast through forward and reverse signaling. We previously found that erythropoietin could affect the expression of some key molecules during the differentiation of osteoclast and osteoblast, with the change of expression of ephrinB2 and EphB4 on the surface of these cells. In order to prove that the role of EPO on bone remodeling is mediated by bi-directional signaling of ephrinB2/EphB4, we will study the effect of EPO on the expression of ephrinB2/EphB4 and their downstream molecules in osteoclast, osteoblast and co-culture system by Real time PCR, Western blot, and cytochemical staining, etc. and identify the role of EPO on the differentiation and function of osteoclast and osteoblast; then we will study the relationship between ephrinB2/EphB4 axis and the expression of osteoclastic and osteoblastic relating molecules under the influence of EPO by gain- and loss-of function through stimulation of gene expression and RNAi technology, etc., and identify the role and mechanism of EPO on bone remodeling mediated by ephrinB2/EphB4 axis; lastly, we will observe the effect of EPO on the regeneration of residual alveolar bone following tooth extraction in rats by Micro CT, histology and immunohistochemistry, etc., which will settle a foundation for treatment of jaw bone destruction by EPO.