【摘要】 背景:成体干细胞具有自我更新和分化为多种组织的能力,是组织工程学的重要组成部分。近来研究表明吸脂后人脂肪源性干细胞具有间充质干细胞的特点,能体外诱导分化为心肌细胞,但尚无对人心包外脂肪干细胞特点及诱导分化为心肌细胞的报道。目的:探讨人心包外脂肪干细胞体外培养及向心肌诱导分化的时期。方法:取人心包外脂肪组织,体外分离培养传代后,细胞免疫学检测不同时期细胞表面特异性抗原CD44,CD90的表达,并比较荧光强度,选择最佳诱导时期利用心肌培养基诱导培养后,免疫细胞化学检测心肌特异性抗α-actin、cTnT的表达,进行表型鉴定。结果与结论:人心包外脂肪干细胞体外培养过程中贴壁生长,增殖能力强,形态呈长梭形,旋涡状排列;其表面标记物CD44,CD90表达阳性,并在3、4代细胞中荧光强度达峰值,CD34,CD45表达阴性。经心肌诱导培养基体外诱导培养后,分化的细胞大多呈肌细胞样,细胞免疫化学检测证实心肌特异性抗α-actin、cTnT表达阳性,且在3、4代细胞数量达峰值,结果表明人心包外脂肪干细胞具有间充质干细胞的形态特征及细胞免疫学特征,能体外诱导分化为心肌细胞,存在最佳诱导时期。更多还原

【Abstract】 BACKGROUND: Adult stem cells are capable of proliferation and differentiation, which are an important part of tissue engineering. Although several studies have demonstrated that human adipose-derived stem cells obtained from elective liposuction procedures represent the characters of mesenchymal stem cells and can be induced to differentiate into myocardial cells, less is known about the characters of extrapericardial adipose-derived stem cells and their differentiation into myocardial cells. OBJECTIVE: To explore the culture of extrapericardial adipose-derived stem cells in vitro and their ability to differentiate into myocardial cells. METHODS: The extrapericardial adipose tissues were obtained and then isolated, cultured and passaged in vitro. The expressions of cell surface specific antigens(CD44 and CD90) were detected by immunofluorescence assay at different time periods, and the fluorescence intensity was compared. After induced and cultured with myocardium induction medium for an optimal period, α-actin and cardiac troponin T expressions were detected by immunocytochemical detection and the phenotypic identifications were performed. RESULTS AND CONCLUSION: During the in vitro culture, extrapericardial adipose-derived stem cells adhered to culture flask wall and proliferated strongly. The cells appeared to be shuttle-shaped and exhibit a vortex alignment. They were positive for CD44 and CD90, and the fluorescence intensity reached the peak at passages 3 and 4, but negative for CD34 and CD54. After induced and cultured with myocardium induction medium, the differentiated cells were muscle-like cells, the expression of α-actin and cardiac troponin T were positive, and thenumber of cells reached the peak at passages 3 and 4. These findings suggested that the extrapericardial adipose-derived stem cells from human represent the morphological and cellular immunological characters of mesenchymal stem cells, and they can be induced to differentiate into myocardial cells. In addition, there is the best induction period.更多还原