目前牙髓再生术的最大问题是难以形成规则的牙髓组织，实现牙髓牙本质复合体的再生及其生理功能的重建。感染根管内微生物及其毒力因子的残存将直接影响牙髓再生效果。牙龈卟啉单胞菌(P.gingivalis)是牙周牙髓根尖周疾病的重要致病菌，其致病因子脂多糖(LPS)可能通过SDF-1α/CXCR4/CXCR7调控干细胞的迁移，决定牙髓再生治疗中起主导作用的干细胞种类，从而影响牙髓再生术效果。本项目拟以牙髓再生和根管感染作为切入点，研究P.gingivalis LPS对不同干细胞迁移的影响，采用Transwell实验、基因表达谱芯片技术、蛋白质谱分析、Biacore(SPR)分子相互作用技术，从分子、细胞、个体水平探讨SDF-1α/CXCR4/CXCR7信号通路在这一过程中发挥的重要作用，揭示促进牙髓牙本质复合体再生的关键分子机制，为进一步寻找牙髓再生的有效临床路径、实现理想的牙髓再生提供理论依据。

Currently, the biggest problem of regenerative endodontics is the difficulty to form regular dental pulp tissue and realize the dentin-pulp complex complete regeneration. It is hard to thoroughly clear microorganism and its virulent factors from infected canals, which may directly affect the effect of endodontic regeneration. Porphyromonas gingivalis is the main microorganism in the pathogenesis of periodontal and endodontic diseases. Its virulent factors, lipopolysaccharide (LPS) may regulate migration of stem cells through SDF-1α/CXCR4/CXCR7 axis, control the stem cell types which play the leading role in regenerative endodontic procedures, and influence the result of endodontic regeneration. This project intends to explore the impact of LPS on different stem cells migration through transwell experiment, gene microarray analysis, proteome analysis, Biacore analysis and so on, to reveal the important role of SDF-1α/CXCR4 /CXCR7 signaling in this process. This project aims to study the key molecular mechanism of dentin-pulp complex regeneration, in order to provide theoretical guidance to further promoting the histological effect of regenerative endodontics and realizing ideal endodontic regeneration.