In Vitro Differentiation Capacity of Neuronal Stem Cells

描述（由申请人提供）：目前，许多努力是针对区分 胚胎干（ES）细胞在培养物中分化为特定谱系，用于为移植提供体细胞来源的临床目的。为了充分利用成体和胚胎干细胞的潜力，必须实现维持干细胞作为干细胞的内在/外在控制以及然后可以将它们沿着特定谱系推动的外在控制。有了这些信息，干细胞可以被引导到指定的命运，以便在毁灭性疾病，损伤或出生缺陷的替代疗法中发挥作用。ES细胞能够形成所有细胞谱系，但是短暂的，而成体干细胞似乎永久地存在于大多数组织中，包括脑、骨髓、肝脏、皮肤和肌肉，并且被认为具有更有限的分化能力。来自成年小鼠脑的神经干细胞（NSCs）最近被证明是多潜能的，如果放置在适当的体内环境中，能够形成大多数细胞谱系。然而，关于体外分化知之甚少， NSC的能力。为了检验胚胎、成体和衰老的NSC在分化能力上等同于ES细胞的假设，我们有3个目标：（1）比较NSC和ES细胞沿着神经元谱系向多巴胺能神经元的分化，（2）比较NSC和ES细胞沿着神经/内分泌途径向胰岛的分化，和（3）评估分化细胞移植入同系或免疫缺陷宿主后的功能。本研究的目的是收集小鼠神经干细胞（NSC）和小鼠胚胎干细胞（ES）在体外沿着指定途径分化并在体内发挥功能的能力的比较研究的初始数据。这些数据对于我们理解干细胞生物学及其潜在的治疗用途至关重要。

DESCRIPTION (provided by applicant): Currently much effort is directed toward differentiating embryonic stem (ES) cells to specific lineages in culture for the clinical purpose of providing a source of somatic cells for transplants. To take advantage of the full potential of stem cells, both adult and embryonic, the intrinsic/extrinsic controls that maintain stem cells as stem cells and the extrinsic controls that can then push them along a specific lineage must be realized. With this information, stem cells may be guided to prescribed fates in order to function in replacement therapies for devastating diseases, injury, or birth defects. ES cells are capable of forming all cell lineages, but are transient, while adult stem cells appear to reside permanently in most tissues, including brain, bone marrow, liver, skin and muscle, and are thought to have a more limited capacity for differentiation. Neural stem cells (NSCs) from the adult mouse brain were recently shown to be multipotential, capable of forming most cell lineages, if placed in the appropriate in vivo environment. However, little is known concerning the in vitro differentiation capacity of NSCs. To test the hypothesis that embryonic, adult, and aging NSCs are equivalent to ES cells in their capacity for differentiation, we have 3 aims: (1) to compare NSC and ES cell differentiation along a neuronal lineage to dopaminergic neurons, (2) to compare NSC and ES cell differentiation along a neuro/endocrine pathway to pancreatic islets, and (3) to assess the functionality of differentiated cells following transplantation into syngenic or immunodeficient hosts. The goal of this proposal is to gather initial data for a comparative study of mouse neural stem cells (NSCs) and mouse embryonic stem (ES) cells in their capacity to differentiate along prescribed in vitro pathways and then to function in vivo. This data is crucial for our understanding of stem cell biology and its potential therapeutic use.