利用干细胞移植进行牙周骨组织的再生是当前口腔再生领域的研究热点，但细胞移植后由于炎症等不利因素导致细胞存活数目急剧下降，严重制约了干细胞的应用。移植干细胞的同时引入抗凋亡、促分化的因子，改善移植部位微环境，是提高干细胞再生效率的关键。研究表明凋亡抑制因子FGF2能够上调PI3K-AKT信号途径，AKT能够抑制TNFα凋亡通路中的caspase-9、GSK-3、FoxO1，从而抑制细胞凋亡。因而，本研究将FGF2因子与乳牙牙髓干细胞（SHED）同时包埋入纤维蛋白胶(fibrin)支架，促进干细胞移植后的存活，同时埋入BMP2脂质体纳米球，促进干细胞存活后的成骨分化，并利用超顺磁性氧化铁纳米颗粒（SPIO）标记SHED进行干细胞移植后的MRI活体追踪，探讨FGF2/BMP2纳米序贯缓释系统在炎症微环境下促进SHED修复牙周骨缺损的作用机制。

The study on transplantation of stem cells for periodontal tissure regeneration is one of the most popular subjects in the field of oral regeneration at present. However, there is a sharp decline in the number of living transplanted cells after transplantation because of the poor living environment such as inflammation. This phenomenon has restricted the application of stem cells seriously. It is an effective method for improving the microenvironment by introducing factors which could inhibit apoptosis and induce differentiation while cells were tranplanted. TNFα is a major pro-apoptotic factor in the inflammatory microenvironment. FGF2 is an anti-apoptotic factor. Studies revealed that FGF2 could upregulate PI3K-AKT signaling pathway, and AKT could inhibit caspase-9, GSK-3 and FoxO1 which play important roles in TNFα induced apoptosis pathway. Thereby FGF2 could inhibite apoptosis of cells. In this study we will embed both FGF2 factors and SHED into the fibrin glue scaffolds to promote the survival of stem cells after transplantation. In the meanwhile BMP2 nanoliposomes are embeded into the gel to improve the osteogenic differentiation of stem cells. In order to tracke the cells in vivo SHED are labled with superparamagnetic iron oxide particles (SPIO) before transplantation. In all this study will investigate the mechanism of FGF2 and BMP2 sequential and sustained-release system in promoting SHED survival and osteogenic differentiation for repair of periodontal bone defects in inflammatory microenvironment.