Lin28/Let-7调控的骨髓间充质干细胞移植治疗阿尔茨海默病的实验研究

骨髓间充质干细胞（MSCs）移植治疗阿尔茨海默病（AD）是一种极具潜力的方法。提高MSCs质量，以适应AD病理状态下的移植微环境是其成功前提。通过前期对MSCs神经分化的研究，本课题提出Lin28/Let-7在MSCs移植治疗AD中可能起到多靶点的调控作用。以Lin28/Let-7为靶点，按照Gain和Loss of function原则，拟采用腺相关病毒载体及miRNA mimic/inhibitor转染；Northern Blot、qRT-PCR、免疫细胞化学染色、Western Blot等方法观察不同Lin28/Let-7背景下MSCs生物学行为、神经分化的差异。并将Lin28/Let-7调控的MSCs移植入转基因AD模型小鼠，观察移植物存活、分化及移植局部微环境组织学改变；评估学习、记忆能力恢复情况。为突破MSCs移植治疗AD的技术“瓶颈”提供新的思路，具有重要的理论和临床意义。

The clinical utility of bone marrow-derived mesenchymal stem cells (MSCs) transplantation in the treatment of Alzheimer's disease (AD) is rapidly expanding. Improving the quality of MSCs grafts and adaptation to the transplant microenvironments of AD pathological state are the prerequisites for success. Based on the former studies of MSCs differentiation into neurons, our research proposes that Lin28/Let-7 may play an important role in the treatment of MSCs transplantation into AD. In accordance with the principles of gain and loss of function, Lin28/Let-7 is targeted and regulated by recombinant adeno-associated virus infection, miRNA mimic or inhibtor transfection. The biological behavior and the variation of neuronal differentiation of MSCs with diverse Lin28/Let-7 are observed by Northern blot,RT-PCR, immunocytochemistry, Western blot, ELISA and other techniques. For further study, MSCs regulated by Lin28/Let-7 are transplanted into AD transgenic mice. We observe the survival and differentiation of MSCs and the histological changes of the local microenvironments. The recovery of learning and memory are assessed by behavioristics. This study may provide new ideas to break the "bottleneck" of MSCs transplantation in the treatment of AD and had important theoretical value and clinical significance.