草酸钙晶体-肾小管上皮细胞相互作用与肾间质矿化的相关性研究

Up to now, it was unknown of Randall’s plaques(RP)formation mechanism. Calicum oxlate(CaOx) stones were considered from RP and had association with renal interstitial calcification.The accumulated evidences demonstrated that the adhesion of CaOx crystals to the membrane of renal tubular epithelium was essential to the renal CaOx stone formation. The interaction between CaOx crystals and renal tubular epithelium, named the crystal-membrane interaction, not only played an important role in regulating the adhesion of crystals to cell membrane but also triggerd a cascade of molecular events occurence (ROS/OS，p38 MAPK、OPN和TGF-β1).The evidences indicated that the molecular events participated in bone formation and vascular calcification. Therefore, we presumed the molecular events would be a bridge between crystal-membrane attachment and renal interstitial calcification. It was the main mechanism of biomineralization.In body, the extracellular matrix calcification mediated by was the important mechanism for biomineralization. In the present study, our strategy was to employ the quantitative proteomics technology and bioinformatics tools to explore the associations between the known important pathways involved in crystal-membrane interaction and biomineralization and matrix vesicle mineralization-related proteins secreted from renal tubular epithelial cell-renal interstitial fibroblasts mineralizated co-cluture model.On the basis of the results above, the hypothesis was proposed and addressed in human multicellular co-culture model for simulation of renal papillary microenvironment. The prsent study is an expandation for previous work. Our study was hope to discover the important proteins taking participate in the early stage of RP formation and explore their function.In conclusion, our study will provide the new inspiration and targets for further study to inhibit or control of occurrence and development of RP.

肾间质钙斑（RP）发生机理至今尚不明确。起源于RP的CaOx结石被认为与肾间质矿化相关。CaOx晶体粘附到肾小管上皮细胞是CaOx结石形成的始动因素。CaOx晶体与肾小管上皮细胞的相互作用不仅调控晶体粘附，还会触发一系列级联发生的分子事件(ROS/OS，p38 MAPK、OPN和TGF-β1等)。这些分子事件也参与骨形成和血管钙化。因此我们推测这些分子事件可能是晶-膜粘附和肾间质矿化之间的桥梁。基质小泡介导的细胞外基质钙化是体内生物矿化发生的最主要机制。本项目中，我们拟探讨矿化的肾小管上皮细胞-肾源成纤维细胞共培养模型来源的基质小泡矿化相关蛋白与已知的晶-膜相互作用和生物矿化之间的相关性，提出工作假说，并在构建的模拟肾乳头微环境的人多细胞共培养模型中验证。本项目是既往工作拓展，将有望发现参与RP形成起始阶段的重要蛋白质并揭示其作用机制，为进一步研究干预和控制RP发生提供新的启示和研究靶点。

肾间质钙斑（RP）发生机理至今尚不明确。起源于RP的CaOx结石被认为与肾间质矿化相关。CaOx晶体粘附到肾小管上皮细胞是CaOx结石形成的始动因素。晶膜互作不仅调控晶体粘附，还会触发一系列级联发生的分子事件。推测：这些分子事件可能是晶-膜粘附和肾间质矿化之间的桥梁。本项目中，我们使用单细胞转录组学技术，首次建立高分辨肾脏RP细胞图谱。其中，IC、PC和LOH细胞群不仅存在矿化通路显著上调，而且分别与固有免疫（LOH）、补体（IC）及先天免疫（PC）相关。值得一提的，在上述3组细胞群中执行矿化功能的基因不完全相同。另外，LOH和IC细胞群出现显著的Wnt和PI3K-Akt 信号通路上调。 Wnt和PI3K-Akt 信号通路是肾小管上皮间质转化（EMT）中最重要的机制。也就是说，晶-膜粘附过程中，驱动肾小管EMT发生的Wnt和PI3K-Akt 信号通路同时也将诱导肾间质发生矿化。这一过程中，很可能受机体固有免疫水平影响，由整合素、胰岛素样因子、干扰素诱导蛋白等介导调控ECM重塑和ACP相变实现。目前这些发现，均未见报道。