脂肪源性干细胞的体外分离培养与鉴定

背景：脂肪间充质干细胞来源丰富、取材方便、体外有较强增殖能力并具有多向分化的潜能,有望成为组织工程的种子细胞。目的：体外分离培养SD大鼠脂肪干细胞并进行鉴定。方法：取SD大鼠腹股沟区皮下脂肪组织,0.075%I型胶原酶消化分离、培养脂肪源性干细胞,倒置相差显微镜下观察脂肪源性干细胞的细胞形态和增殖特征。取第3代细胞用MTT比色法描绘生长曲线,免疫荧光法鉴定干细胞标志物CD44,含有体积分数10%胎牛血清、地塞米松和胰岛素的DMEM/F12定向诱导成脂分化,油红“O”染色成脂分化鉴定。免疫组化法鉴定向神经细胞诱导分化的结果。结果与结论：分离出的大鼠脂肪源性干细胞生长曲线呈“S”形,强烈表达干细胞标志物CD44。成脂诱导分化经油红“O”染色呈橘红色。向神经细胞诱导分化后表达神经元标志物神经元特异性烯醇化酶。说明SD大鼠脂肪源性干细胞在体外具有易于分离培养和扩增,表达间充质干细胞相关表型,特定条件下可诱导分化的特点。

In vitro isolation,culture and identification of adipose-derived stem cells

BACKGROUND:Adipose-derived stem cells are easily collected and abundantly cultured, which can proliferate rapidly when being cultured in vitro. With multi-directional differentiation potential, adipose-derived stem cells are expected as seed cells for tissue engineering.OBJECTIVE:To isolate, culture and identify of adipose-derived stem cells from Sprague-Dawley rats in vitro.METHODS:The subcutaneous adipose tissue was obtained from the iliac region of rats under the aseptic condition, and then was digested with 0.075% type Ⅰ collagenase and cultured in vitro. The morphology and proliferation characteristics of the cells were observed under an inverted phase contrast microscope. The third passage was put into gauge for growth curve by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, and the cells were also identified by CD44, a stem cell marker, with immunofluorescence staining. Adipose-derived stem cells were induced and differentiated into adipocytes in Dulbecco’s modified Eagle’s medium/Ham’s nutrient mixture F-12 containing 10% fetal bovine serum, dexamethasone and insulin, and then the cells were identified with oil red “O” staining. Adipose-derived stem cells were induced and differentiated into neural cells, and then the cells were identified with immunohistochemical staining.RESULTS AND CONCLUSION:The growth curve of adipose-derived stem cells was opposite-like “S” shape, and it strongly expressed CD44 that can designate a stem cell. The passage cells were exposed to a defined medium for adipocyte differentiation, and then could be stained with oil red. After being induced and differentiated into nerve cells, the cells expressed neuron-specific enolase. The adipose-derived stem cells of Sprague-Dawley rats are characterized by easy isolation, culture and proliferation in vitro, expressing related phenotypes of mesenchymal stem cells, as well as induction and differentiation under certain conditions.