不同硬度聚丙烯酰胺调控骨髓间充质干细胞的定向分化  

Directed differentiation of bone marrow mesenchymal stem cells under regulation by polyacrylamide with different stiffness

作　　者：郭江龙 何静[1] 吴方[1] Guo Jiang-long;He Jing;Wu Fang(National Engineering Research Center for Biomaterials,Sichuan University,Chengdu 610000,Sichuan Province,China)

机构地区：[1]四川大学,国家生物材料工程研究中心,四川省成都市610000

出　　处：《中国组织工程研究》2018年第25期3981-3986,共6页Chinese Journal of Tissue Engineering Research

基　　金：国家自然科学基金项目(81671826);国家重点研发计划(2016YFC1101903)。

摘　　要：背景:基底材料硬度可以直接影响干细胞的分化命运,但是干细胞向不同体细胞分化的敏感程度及调控机制目前尚不清楚。目的:探讨基底力学性能对骨髓间充质干细胞分化的影响及其机制。方法:通过调控聚丙烯酰胺的力学强度,使之弹性模量分别与神经组织(0.5 k Pa)、软骨组织(10 k Pa)、心肌组织(20 k Pa)以及骨组织(40 k Pa)类似。采用酶联免疫吸附法检测骨髓间充质干细胞在不同弹性模量基底上的分化情况,采用细胞骨架染色及免疫荧光染色观察骨髓间充质干细胞在基底上的细胞骨架形态以及黏着斑蛋白表达。结果与结论:(1)骨髓间充质干细胞在低硬度基底上向神经和软骨方向分化趋势明显,而高硬度基底上向心肌以及成骨方向分化的趋势不明显,说明骨髓间充质干细胞向神经以及软骨方向分化时,对材料的力学性能敏感,向心肌以及成骨方向分化时对材料的力学性能不敏感;(2)随着基底硬度的提高,黏着斑蛋白的表达量增高,说明在低硬度基底上,骨髓间充质干细胞感应的力学信号较低,激活了某些与软骨和神经分化相关的信号通路的表达,从而促进干细胞向神经和软骨方向分化。BACKGROUND:The hardness of substrate materials can directly affect the differentiation fate of stem cells,but the sensitivity and regulatory mechanism of stem cells differentiating into different somatic cells are still unclear.OBJECTIVE:To explore the effect of substrate mechanical properties on the differentiation of bone marrow mesenchymal stem cells and its mechanism.METHODS:In this study,the mechanical strength of polyacrylamide was modulated to be similar to that of nerve tissue(0.5 kPa),cartilage tissue(10 kPa),myocardial tissue(20 kPa)and bone tissue(40 kPa),respectively.Differentiation of bone marrow mesenchymal stem cells on the substrate with different elastic moduli was detected using ELISA,and cytoskeleton morphology and vinculin expression were detected using cytoskeleton staining and immunofluorescence staining.RESULTS AND CONCLUSION:(1)Bone marrow mesenchymal stem cells on the substrate with low stiffness trended to differentiate into nerve and cartilage,while the cells on the substrate with high stiffness had no obvious trend to differentiate into cardiocytes and osteoblasts.This indicated that bone marrow mesenchymal stem cells were sensitive to the mechanical properties of the material during nerve and cartilage differentiation,while were insensitive to the mechanical properties of the material during cardiocyte and osteoblast differentiation.(2)The expression level of vinculin increased as the substrate stiffness increased,indicating that the mechanical signals induced by bone marrow mesenchymal stem cells on low stiffness substrates are relatively low,which can activate certain signaling pathways related to cartilage and neural differentiation.

关 键 词：骨髓间充质干细胞 聚丙烯酰胺 细胞分化 细胞骨架 力学信号 黏着斑蛋白 干细胞 国家自然科学基金 丙烯酰胺类 骨髓 间质干细胞 细胞分化 组织工程 

分 类 号：R394.2[医药卫生—医学遗传学]