心肌组织裂解液诱导骨髓间充质干细胞向心肌样细胞的分化

Effects of myocardium lysate on the differentiation of rat bone marrow-derived mesenchymal stem cells into cardiac myocyte in vitro

背景:干细胞具有"环境依赖性分化"特性,以心肌组织裂解液模拟心肌微环境诱导骨髓间充质干细胞向心肌细胞方向分化的研究甚少。目的:观察心肌组织裂解液对大鼠骨髓间充质干细胞向心肌细胞方向分化的影响。方法:选用生长良好的第2代骨髓间充质干细胞,加入诱导液连续培养5周,连续观察细胞形态学特征的变化规律,采用α-Actin进行免疫细胞化学染色观察干细胞是否向肌细胞方向分化,收集诱导后的细胞行苏木精-伊红染色观察是否存在闰盘,并通过电镜观察其超微结构。结果与结论:加入诱导液后大部分细胞呈"竹节样",α-Actin免疫细胞化学染色阳性,表明间充质干细胞向肌细胞方向分化;苏木精-伊红染色可见闰盘,透射电镜下见排列整齐明暗相间的肌丝,扫描电镜下可见胞浆内有纤维状结构,说明"竹节样"细胞具有心肌细胞的典型形态结构特点。连续诱导12d多个区域出现成片的、具有自律性搏动的多核肌管结构。心肌组织裂解液可模拟心肌细胞的微环境,诱导骨髓间充质干细胞分化为具有典型形态结构特征和相应功能活动的心肌样细胞。

BACKGROUND：Stem cells have the characteristics of ＂differentiation dependent on enviroment＂,little research have focused on myocardium lysate that simulating the microenvironment of cardiocyte induce bone marrow mesenchymal stem cells（BMMSCs） differentiated into cardiocyte-like cells.OBJECTIVE：To investigate the effects of myocardium lysate on the differentiaion of bone marrow mesenchymal stem cells into myocardial-like cell.METHODS：Changes of morphological characteristics of the second passaged BMMSCs that cultured with medium contained myocardium lysate for 5 weeks were observed.After the procedure of induction,α-Actin was used to observe whether BMMSCs differentiate into cardiocyte-like cells,hematoxylin-eosin staining was used to identify whether intercalated disk was existed,while electron microscopys was used to assess the ultrstructure of the induced cells.RESULTS AND CONCLUSION：Most of the induced cells like bamboo in microscopys,positive reaction after α-actin immunocytochemical stain showed that the BMMSCs were differentiated into myo-like cells.Intercalated disk,well sequenced sarcomeres and myofilaments of the cytoplasm observed revealed the bamboo-like cells have the typical morphology of cardiocyte.Spontaneous beating myotube-like structures generated at 12 days after induction.In brief,the myocardium lysate can imitating the microenvironment of cardiocyte,induce BMMSCs differentiated into cardiocyte-like cell which have the typical morphology of cardiocyte and the corresponding functional activities.