体外诱导人脐静脉间充质干细胞分化为神经元样细胞的实验研究

探讨来源于人脐静脉内皮及内皮下分离的间充质干细胞(MSCs)向神经元样细胞分化的可能性,以期为脐静脉MSCs的神经移植提供理论依据。通过在无菌条件下收集正常足月剖宫产新生儿脐带并对脐静脉进行胶原酶消化,将获取的内皮及内皮下贴壁细胞进行培养。经传代培养及免疫细胞化学鉴定后,取第2代细胞用β-巯基乙醇和二甲基亚砜诱导其向神经元方向分化,并以免疫细胞化学方法对分化细胞进行鉴定。结果表明脐静脉经胶原酶消化后的贴壁细胞主要表现为间充质样细胞和内皮细胞;传2代后,间充质样细胞可得到纯化和扩增。免疫细胞化学染色显示诱导前细胞不表达血管性血友病因子(vWF),诱导后MSCs表达巢蛋白(nestin)和神经元特异性烯醇化酶(NSE),而不表达胶质纤维酸性蛋白(GFAP)。以上结果提示,来源于脐静脉内皮及内皮下的MSCs在体外可以培养、扩增,并具备在诱导剂的作用下向神经元样细胞分化的潜能,可作为神经系统疾病细胞移植治疗的备选来源。

STUDY ON THE INDUCED DIFFERENTIATION OF HUMAN UMBILICAL VEIN MESENCHYMAL STEM CELLS INTO NEURON-LIKE CELLS

By investigating the regeneration feasibility of mesenchymal stem cells(MSCs),which is derived from endothelial and subendothelial cells of human umbilical vein(hUV),to neuron-like cells in vitro,we want to provide new evidence for the transplantation of hUV-derived MSCs to nervous tissue.Human umbilical cords were collected from full term uterine-incision delivered neonatus.By collagenase Ⅰ digestion,endothelial and subendothelial cells were isolated from human umbilical vein and cultured.Then the passage 1 adherent cells were processed for immunocytochemistry analysis and the selected passage 2 MSCs were induced to differentiate to neuron-like cells by BME(β-mercapto ethanol) and DMSO(dimethylsulfoxide).Finally,the differentiated neuron-like cells were identified with immunocytochemical staining.The results showed that the adherent cells obtained from human umbilical vein were mostly mesenchymal-like and endodermic-like.After 2 passages,mesenchymal-like cells can be purified and expanded.Immunohistochemistry staining also showed that the MSCs were negative for vWF before induction;It was positive for nestin and neuron-specific enolase(NSE),while negative for GFAP after induction.The results suggest that MSCs isolated from the endothelial and subendothelial layers of umbilical cord vein can be cultured,expanded and have the potential for differentiating into neuron-like cells under specific culture conditions in vitro.Thus,umbilical vein MSCs may serve as another source of MSC for experimental and clinical use.