大鼠脂肪干细胞体外诱导成平滑肌样细胞的研究

Differentiation of Rat Adipose-Derived Stem Cells into Smooth-Muscle-Like Cells in Vitro

目的:研究大鼠脂肪干细胞(ADSCs)体外单层培养条件下诱导分化为平滑肌样细胞的可行性。方法:从SD大鼠的腹股沟脂肪垫分离获取脂肪干细胞,测定其生长曲线。取第4代细胞用成脂诱导液诱导分化,并用油红O染色鉴定。取第4代细胞用成骨诱导液诱导分化,并用Von Kossa染色鉴定。取第4代细胞用含有β-巯基乙醇的成平滑肌诱导液诱导,并用免疫组化的方法检测α平滑肌肌动蛋白(α-SMA)的表达。结果:脂肪干细胞成梭形和多角形,体外生长迅速,生长曲线表明传代2 d后细胞进入对数生长期。第4代细胞成脂诱导后,油红O染色证实细胞内存在脂滴;成骨诱导后,Von Kossa染色证实有矿化结节。脂肪干细胞诱导平滑肌样细胞免疫组化结果,β-巯基乙醇诱导组和未诱导组细胞α-SMA的表达阳性率分别为(29.80±6.89)%、(2.89±1.24)%。诱导组细胞α-SMA的表达阳性率高于未诱导组,差异有统计学意义(P<0.01)。结论:脂肪干细胞经诱导后出现明显的平滑肌细胞特征,可成为平滑肌相关疾病在组织工程研究上新的种子细胞来源。

Objective： To study the feasibility of inducing the differentiation of rat adipose-derived stem cells （ADSCs） into smoothmuscle-like cells in monolayer culture in vitro. Methods ： ADSCs were obtained from the adipose of the inguinal region of the SD rat. A growth curve of the ADSCs was drawn. The fourth passage ADSCs were induced to differentiate into adipocytes with adipogenic inducing fluid and determined by Oil Red O staining, into osteoblasts with osteogenic inducing fluid and determined by Von Kossa staining, as well as into smooth-muscle-like cells with inducing fluid containing β-mercaptoethanol, and the expression of α-smooth muscle actin （α-SMA） was detected by the immunohistochemical method. Results： The ADSCs presented spindle and polygon shapes and proliferated rapidly in vitro. The growth curve showed the ADSCs in the logarithmic growth phase two days after subculture. The fourth passage ADSCs exhibited red stained lipid droplets characteristic of adipocytes in the cytoplasm on Oil Red O staining after induction with adipogenic inducing fluid, and calcium nodes on Von Kossa staining after induction with osteogenic inducing fluid. The immunohistochemical results of the ADSCs induced into smooth-muscle-like cells showed that the positive rate of α-SMA in the β-mercaptoethanol induced cells was （ 29.80±6.89） % , significantly higher than in the uninduced ones （ [ 2.89 ± 1.24 ] % , P 〈 0.01 ）. Conclusion ： ADSCs displayed obvious characteristics of smooth muscle cells after induction, and could be a new source of cells in the tissue engineering studies of smooth muscle related diseases.