尿液来源的肾脏特异性干细胞对肾脏缺血再灌注损伤的治疗作用及其机制的实验研究

Mesenchymal stem cells hold a great potential for treating kidney ischemia/reperfusion injury (IRI). Accumulated data indicate that mesenchymal stem cells from bone marrow, adipose tissue, amniotic fluid and umbilical cord blood can improve kidney function and limit injury mainly through a paracrine action, a differentiation-independent mechanism, in IRI models. In our previous study, we have successfully isolated and cultured a kind of urine-derived kidney specific stem cells (UD-KSCs). Our study showed that UD-KSCs have a paracrine function and are able to secret many bioactive factors which have important roles in modulating inflammatory response and enhancing cellular activities and angiogenesis. What’s more, these cells can be easily differentiated into kidney podcytes and tubular epithelial cells. Based on our previous studies, UD-KSC is regarded as a novel cell source, which can be simply cultured at a very low cost, for the treatment of IRI. In this study, we will establish the a rat IRI model and investigate the therapeutical effect UD-KSC for IRI after administration by renal artery injection. We will simultaneously use the cell tracing technology to investigate whether these UD-KSC are able to survive and differentiate into kidney cells, and directly contribute to kidney regeneration after transplantation. We will also prepare the UD-KSC conditioned medium, and subsequently investigate the therapeutical effect and possible mechanisms of paracrine bioactive factors from UD-KSC for the treatment of IRI. Finally, we will study the effect of hypoxic preconditioning on the paracine function of UD-KSC and its benefits in the treatment of IRI. This study is designed according to the clinical requirements for cell therapy and our findings will be in favor of the translation from animal researches to clinical applications.

既往研究表明肾外间充质干细胞主要通过旁分泌途径发挥对肾脏缺血再灌注损伤（IRI）的治疗作用，而其直接分化作用在肾脏保护方面的贡献微乎其微。前期研究中,课题组发现尿液来源的肾脏特异性干细胞(UD-KSC)不仅具有旁分泌功能，还能直接分化为肾脏细胞，这为治疗肾脏IRI提供了一种新的种子细胞。在此基础上，课题组将建立肾脏IRI的大鼠模型，进一步研究UD-KSC治疗肾脏IRI的作用，并通过细胞示踪技术明确UD-KSC是否能存活并分化为肾脏细胞，直接参与肾脏再生。同时，课题组还将制备UD-KSC的条件培养基，探讨UD-KSC的旁分泌功能治疗肾脏IRI的作用及其机制。此外，课题组还将通过体内和体外试验研究缺氧预处理是否能增强UD-KSC的旁分泌功能，并增强其治疗IRI的作用。本课题将为UD-KSC治疗肾脏IRI奠定理论基础；同时本课题按照临床要求设计细胞移植途径，有助于推进研究成果的临床转化。

既往研究表明肾外间充质干细胞主要通过旁分泌途径发挥对肾脏缺血再灌注损伤（IRI的治疗作用，而其直接分化作用在肾脏保护方面的贡献微乎其微。本课题组发现尿液来源的肾脏特异性干细胞(UD-KSC)不仅具有旁分泌功能，还能直接分化为肾脏细胞，这为治疗肾脏IRI提供了一种新的种子细胞。在此基础上，课题组将建立肾脏IRI的大鼠模型，进一步研究UD-KSC治疗肾脏IRI的作用。通过细胞示踪技术，未发现UD-KSC能长期存活并分化为肾脏细胞。同时，课题组通过制备UD-KSC的条件培养基，利用UD-KSC的旁分泌的生物活性因子治疗肾脏IRI，我们观察到肾脏结构和功能的改善。此外，课题组也通过体外试验研究，观察到缺氧预处理能增强UD-KSC的旁分泌功能，并增强其治疗IRI的作用。因此，本课题组通过研究发现，UD-KSC不是通过 细胞存活分化，而主要是通过旁分泌功能改善IRI的结构和功能。本课题的结论为UD-KSC治疗肾脏IRI提供了理论基础，UD-KSC更依赖于其旁分泌功能间接机制改善IRI；同时，本课题发现的UD-KSC的生物活性因子的价值，能避免细胞移植的免疫排斥，有助于推进研究成果的临床转化。