猫骨髓基质细胞诱导为神经干细胞的实验研究

背景骨髓基质细胞是贴壁黏附的非造血多潜能干细胞,其在一定条件体外培养、扩增可被诱导分化为神经元和胶质细胞.目的观察家猫骨髓基质细胞体外培养及诱导分化成神经干细胞的生长情况.设计随机取样.单位南方医科大学附属珠江医院神经外科.材料实验于2002-01/12在解放军第一军医大学珠江医院全军神经医学研究所中心实验室进行,实验动物是由第一军医大学动物中心提供健康家猫20只,年龄1.0～2.0岁,体质量2.5～4.0 kg,雌雄各半.干预随机抽取家猫左右下肢的骨髓,从中分离得到骨髓基质细胞,提取的骨髓基质细胞悬液在体外给予神经干细胞培养基培养,增殖后用维甲酸为分化诱导因子进行诱导骨髓基质细胞向神经干细胞转化.CK2型倒置相差光学显微镜(OLYMPAS,JAPAN)追踪观察活细胞培养生长情况,同时观察4,12,24,48 h去除非贴壁细胞及不去除贴壁细胞骨髓基质细胞生长情况.采用免疫组织化学染色改良法对干细胞阶段的骨髓基质细胞进行免疫细胞化学检测,OLYMPAS光学显微镜观察.主要观察指标对接受实验干预的骨髓基质细胞分别进行倒置相差显微镜下观察活细胞生长情况及光镜下观察免疫细胞化学染色情况.结果20只家猫全部进入结果分析.猫骨髓基质细胞在体外培养中胞体增大,倒置相差显微镜下可见丰富的胞浆颗粒,继之出芽,贴壁生长,可形成克隆团,同时可传代培养.免疫组化染色分析结果显示能表达神经干细胞特异性抗原Nestin,而且能分化出胶质细胞样细胞和神经元样细胞.结论家猫骨髓基质细胞具有干细胞特征,在合适条件下可扩增、形成克隆并诱导分化出神经胶质细胞和神经元特征细胞.

Differentiative capability of bone marrow mesenchymal cells into neural stem cells in cats

BACKGROUND: Bone marrow mesenchymal cells, multiple-potential non-hematopoiefic stem cells adhering to the wall in vitro culture, can be induced to proliferate and differentiate towards neurons and glia cells.OBJECTIVE: To investigate the growth state of cat bone marrow mesenchymal cells in vitro culture, as well as the capability to differentiate towards neural stem cells.DESIGN: A randomized sampling study.SETTING: Department of Neurosurgery, Zhujiang Hospital, Southern Medical University.MATERIALS: This study was carried out at the Central Laboratory of the General Military Neurological Research Institute, Zhujiang Hospital, Southern Medical University between January and December 2002. Twenty healthy home-raised cats, aged 1.0 - 2.0 years and weighing 2. 5 - 4.0 kg, male and female in half, were provided by the Animal Center of the First Military Medical University of Chinese PLA.INTERVENTIONS: Bone marrows were randomly aspirated from the left or right hindlimbs in order to separate bone marrow mesenchymal cells, then the bone marrow mesenchymal cells single cell suspension was co-cultured with neural stem cell culture media in vitro so as to induce differentiation to neural stem cells with tretinoin. CK2 type inverted optical microscope(Olympus,Japan) was used to observe the growth of bone marrow mesenchymal cells in vitro culture, as well as 4, 12, 24, 48 hours of induction upon eliminating or not eliminating the wall-adhering cells. Bone marrow mesenchymal cells in stem cell stage were identified under Olympus optical microscope with modified immunohistochemical staining.MAIN OUTCOME MEASURES: The growth state and the immunocytochemical staining of living bone marrow mesenchymal cells exposed to experimental intervention were observed under the Olympus inverted optical microscope.RESULTS: Data from the 20 cats were analyzed without loss. Reversed microscopic observation revealed that cat bone marrow mesenchymal cells becrame larger when cultured in vitro, which were rich in plasmic granules with prominence projecting, adhering to the wall and forming cell clones. These cells were then successively cultured, and imnunohistochemical staining analysis suggested that the passaged bone marrow mesenchymal cells could express neural stem cells-specific antigen Nestin and differentiate towards glia-like cells and neuron-like cells.CONCLUSION: Cat bone marrow mesenchymal cells possess the characteristics of stem cells; they can be amplified into cell clones and induced to express the property of neural glia cells and neuron-like cells under proper condition.