PKH26标记的骨髓间质干细胞在阿尔茨海默病大鼠中的迁移

摘要

目的:研究荧光染料PKH26标记的骨髓间质干细胞(bone-marrow derived mesenchymal stem cells,BM-MSC)在阿尔茨海默病(Alzheimer′s disease,以下简称AD)大鼠中的迁移.方法:抽取正常人骨髓,体外分离培养BM-MSC;以PKH26标记第5代BM-MSC,采用流式细胞仪检测BM-MSC表面标记物,并在荧光显微镜下观察PKH26标记率；将PKH26标记的BM-MSC尾静脉注射到正常对照组和AD动物模型组,14天后在大鼠海马区,用荧光显微镜观察PKH26标记的BM-MSC 细胞.利用Morris水迷宫实验比较AD模型组和BM-MSC移植组空间学习记忆能力.结果:流式细胞仪检测BM-MSC表面标记物CD73和CD105呈阳性,在体外BM-MSC的PKH26标记率达100％.Morris水迷宫实验比较BM-MSC移植组和AD动物组,BM-MSC移植组在第13、14天时空间学习记忆能力比AD动物组有显著改善.在移植BM-MSC的大鼠海马区可发现PKH26标记的BM-MSC阳性细胞,与DAPI吻合.PKH26阳性细胞在AD动物模型组明显多于正常对照组.结论:BM-MSC不仅能通过AD大鼠的血脑屏障,而且存活在AD大鼠的海马区,并有能够改善AD模型大鼠的学习障碍.%Objective: To investigate the migration of fluorescent dye PKH26 -labeled BM-MSC in the Alzheimer's model rats. Methods: Normal human bone marrow extracted for isolation of BM-MSC was cultured in vitro. The 5th passaged BM-MSC was labeled with PKH26,and observed under a fluorescence microscope for PKH26 labeling efficiency, and using flow cytometry BM-MSC surface markers was checked. The PKH26 labeled BM-MSC injected into the tail vein of the normal control group and AD rnanimal model group, 14 days after finding the PKH26-labeled BM-MSC cells in the rat hippocampus using fluorescence microscopy. Using the Morris water maze experiment comparison of AD model and BM-MSC transplantation group of spatial learning and memory ability. Results: Flow cytometry showed BM-MSC surface markers CD73 and CD105 were positive. In vitro ,PKH26-labeled rate of BM-MSC was 100% . The Morris water maze experiment comparison of BM-MSC transplantation group and AD group of animals, BM-MSC transplantation group at 13,14 days of spatial learning and memory ability than AD animal group had significantly improved. 14 days after BM-MSCs in rat hippocampus could be found which were PKH26-positive, consistent with DAPI staining. PKH26-positive cells in animal models of AD were significantly more than those in the normal control group. Conclusion; BM-MSC in AD rats not only migrates through the blood-brain barrier, but also mainly survives in the hippocampus of AD rats, and it can improve AD rat model of learning disabilities.