The derivation of pituitary cells from human ES cells

 描述（由申请人提供）：该提案旨在设计一种基于细胞治疗的垂体功能减退症方法，特别关注放射损伤引起的垂体功能障碍。脑下垂体是一个主要的内分泌器官，在下丘脑的直接控制下，协调生物体中多个腺体的功能。垂体功能减退症是一个非常普遍的问题后，放射治疗的大脑。它是剂量相关的、渐进的和不可逆转的;它还导致癌症幸存者生活质量差和其他重大问题。垂体功能减退症也是感染、创伤性脑损伤或先天性疾病的重要永久性后果。我们已经开发了一种从人ES细胞中分化出垂体细胞并进一步分化为激素产生细胞的方法。我们之前还使用临床相关的分次放射过程优化了大鼠脑放射模型。对动物的生长、体重和行为参数进行了充分的研究，我们有一些垂体功能障碍的初步证据。在这里，我们建议优化人ES和iPS分化方案，以允许富集成特定的垂体细胞亚型。细胞表型的验证是通过 基因表达和标志物谱、激素分泌的测量以及体内功能。将人ES衍生的垂体细胞移植到切除垂体的裸大鼠中，并在不同时间点测量血清中的基础激素水平。将移植物皮下或原位置入下丘脑/垂体界面。我们还将把这些细胞移植到有脑垂体损伤迹象的受辐射大鼠体内。分析将集中在血浆中激素水平的恢复，以及使用刺激试验的移植物整合到下丘脑-垂体轴中的证据。此外，功能分析将尝试通过询问移植细胞的雌性大鼠是否可以恢复其繁殖和哺乳能力来进行。该提议解决了一个迄今为止很少受到关注的新问题。随着我们成功地在癌症患者中实现长期缓解，幸存者生活质量差的问题变得更加紧迫。该项目将提供急需的洞察基于细胞的治疗的可行性，以改善脑辐射的这些后果。它还将从人类ES或iPS细胞中衍生出特定的垂体细胞亚型，这是迄今为止在人类细胞中尚未报道的成就。

 DESCRIPTION (provided by applicant): This proposal aims at designing a cell-therapy based approach to hypopituitarism , with special focus on pituitary dysfunction due to radiation injury. The pituitary gland is a master endocrine organ that orchestrates the function of multiple glands in the organism, under direct control by the hypothalamus. Hypopituitarism is a very prevalent problem following radiation treatment to the brain. It is dose-related, progressive and irreversible; it also contributes to poor quality of life and other substantial problems among cancer survivors. Hypopituitarism is also an important permanent consequence of infection, traumatic brain injury or congenital conditions. We have developed a protocol for the specification of pituitary cells from human ES cells and further differentiation into hormone producing cells. We have also previously optimized a brain radiation model in the rat, using a clinically relevant fractionated radiation course. The animals are well studied for growth, weight and behavioral parameters and we have some preliminary evidence of pituitary dysfunction. Here we propose to optimize the human ES and iPS differentiation protocol to allow the enrichment into specific pituitary cell subtypes. Validation of cell phenotypes is obtained through gene expression and marker profiles, measurements of hormone secretions, as well as in vivo function. Human ES derived pituitary cells are grafted into hypophysectomized nude rats and basal hormone levels are measured in the serum at different time points. Grafts will be placed subcutaneously or orthotopically into the hypothalamus / pituitary interface. We will also graft the cells into the irradiated rats with evidence of pituitary damage. Analysis will focus on revovery of hormone levels in the plasma, as well as evidence of integration of the graft into the hypothalamic - pituitary axis, using stimulation tests. Furthermore, functional analysis will be attempted by asking whetehjr female rats with cell grafts can recover their ability to reproduce and lactate.The proposal addresses a novel problem that has received little attention to date. As we succeed in achieving long term remission among cancer patients, questions of poor quality of life among survivors have acquired a more pressing nature. This project will provide much needed insight into the feasibility of cell based therapy to ameliorate these consequences of brain radiation. It will also undertake the derivation of specific pituitary cell subtypes from humn ES or iPS cells, an unreported achievement in human cells to date.