Proliferation and Differentiation of Retinal Stem Cells

视网膜干细胞的增殖和分化

• 批准号: 7689516
• 负责人: Michael A Dyer
• 金额: $ 61万
• 依托单位: ST. JUDE CHILDREN'S RESEARCH HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7689516
• 关键词: Adult; Affect; Area; Arts; Benchmarking; Biological; Blindness; Cell Differentiation process; Cell Therapy; Cell division; Cell model; Cells; Cellular biology; Characteristics; Ciliary epithelium; Clonal Expansion; Condition; Data; Development; Electrons; Epithelial Cells; Eye; Future; Genetic; Government; Graft Rejection; Growth; Growth Factor; Human; In Vitro; Individual; Laminin; M cell; Microscopic; Molecular; Molecular and Cellular Biology; Morphology; Mus; Mutant Strains Mice; Neuroglia; Neuronal Differentiation; Neurons; Organ; Pathway interactions; Pattern; Persons; Photoreceptors; Pigments; Population; Pre-Clinical Model; Production; Proliferating; Property; Public Health; Purpose; Research; Research Proposals; Retinal; Retinal Degeneration; Retinal Diseases; Series; Serum; Slide; Stem cells; Systems Biology; Testing; Therapeutic Intervention; Tissues; Transplantation; Vision; cell growth; cellular imaging; clinically relevant; design; improved; in vivo; innovation; nerve stem cell; progenitor; research study; response; retinal neuron; retinal progenitor cell; retinal rods; stem; synaptogenesis; transdifferentiation; transmission process

DESCRIPTION (provided by applicant): Cells in the ciliary epithelium (CE) of the eye can clonally expand in culture to produce spheres of cells that differentiate into retinal neurons and glia. It is believed that these spheres are produced by retinal stem cells (RSCs) and hold promise for cell-based therapies to treat degenerative retinopathies. To improve our understanding of RSC expansion and differentiation, we have carried out a series of preliminary studies on human and mouse CE-derived spheres. Our data have led us to reconsider the current retinal stem cell model and to propose a new hypothesis on the expansion and differentiation of CE-derived cells. We propose that the pigmented CE cells rather than RSCs, expand to form spheres and subsequently transdifferentiate into rods, bipolar cells and M¿ller glia. This proposal will test if CE-derived spheres form by proliferative expansion of pigmented CE cells or by an RSC mechanism (Aim 1). Culture experiments and in vivo transplantation studies will also be done to test whether pigmented CE cells transdifferentiate into retinal neurons and glia, or if those cells are produced from retinal stem/progenitor cells (Aim 2). Distinction between these 2 hypotheses must be made, because the pathways regulating proliferation and differentiation in retinal stem/progenitor cells differ from those in epithelial cells, and efforts to optimize expansion and differentiation of CE-derived cells must focus on the pathway that reflects that system's biology. The successful completion of these experiments may substantially affect future development of cell-based therapies for millions of people worldwide who suffer from retinal degeneration. This research proposal will also move the RSC field forward by resolving several outstanding questions regarding the proliferation and differentiation of CE-derived cells in culture and in vivo. PUBLIC HEALTH RELEVANCE: Retinal degeneration affects millions of people worldwide each year. One approach that is being considered to treat degenerative retinopathies is the use of retinal stem cell-based therapy to repopulate the photoreceptors and other cells that are lost. Retinal degeneration is an ideal candidate for such cell-based therapy because the eye is easily accessible for therapeutic intervention and the immunoprivileged status of the eye makes rejection of grafted cells less likely than in other organs where stem cell-based therapies are being considered. However, one of the limitations of the retinal stem cell field compared to other areas of stem cell biology is that it is a relatively new area of research. Cells with properties of stem cells in the ciliary epithelium of the eye were first discovered just 7 years ago. As a result, there are still some important questions that must be answered before we can move forward with therapeutic intervention in humans using retinal stem cells. Specifically, we need to better understand the mechanism of retinal stem cell growth and differentiation in culture. The successful completion of the experiments proposed here will resolve whether there is a retinal stem cell in the ciliary epithelium of the mammalian eye or if pigmented ciliary epithelial cells simply expand and transdifferentiate into retinal neurons and glia. These data are essential for directing future studies on cell-based therapies for retinal degeneration and will have a major impact on moving the retinal stem cell field forward.

描述（由申请人提供）：眼睫状上皮（CE）中的细胞可在培养物中克隆扩增，产生分化为视网膜神经元和神经胶质的细胞球。据信，这些球体是由视网膜干细胞（RSC）产生的，并有望用于治疗退行性视网膜病变的细胞疗法。为了提高我们对RSC扩增和分化的理解，我们对人和小鼠CE衍生球进行了一系列初步研究。我们的数据使我们重新考虑目前的视网膜干细胞模型，并提出了一个新的假设CE衍生细胞的扩增和分化。我们认为，色素的CE细胞，而不是RSC，扩大形成球体，随后转分化成杆，双极细胞和M？ller胶质细胞。本提案将检测CE衍生球体是否通过色素CE细胞的增殖扩增或RSC机制形成（目的1）。还将进行培养实验和体内移植研究，以测试着色的CE细胞是否转分化为视网膜神经元和神经胶质，或者这些细胞是否由视网膜干/祖细胞产生（Aim 2）。必须区分这两种假设，因为调节视网膜干/祖细胞增殖和分化的途径与上皮细胞不同，优化CE衍生细胞扩增和分化的努力必须集中在反映该系统生物学的途径上。这些实验的成功完成可能会极大地影响全球数百万患有视网膜变性的人的基于细胞的疗法的未来发展。这项研究提案还将通过解决有关CE衍生细胞在培养和体内增殖和分化的几个悬而未决的问题来推动RSC领域的发展。公共卫生相关性：视网膜变性每年影响全世界数百万人。正在考虑治疗退行性视网膜病的一种方法是使用基于视网膜干细胞的治疗来重新填充失去的光感受器和其他细胞。视网膜变性是这种基于细胞的治疗的理想候选者，因为眼睛易于进行治疗干预，并且眼睛的免疫豁免状态使得移植细胞的排斥反应比正在考虑基于干细胞的治疗的其他器官更不可能。然而，与干细胞生物学的其他领域相比，视网膜干细胞领域的局限性之一是它是一个相对较新的研究领域。7年前，人们首次在眼睫状上皮中发现了具有干细胞特性的细胞。因此，在我们能够使用视网膜干细胞对人类进行治疗干预之前，仍然有一些重要的问题必须得到回答。具体来说，我们需要更好地了解视网膜干细胞在培养中的生长和分化机制。成功完成这里提出的实验将解决是否有视网膜干细胞在睫状上皮的哺乳动物眼睛，或者如果色素睫状上皮细胞简单地扩大和转分化成视网膜神经元和神经胶质细胞。这些数据对于指导未来基于细胞的视网膜变性治疗研究至关重要，并将对视网膜干细胞领域的发展产生重大影响。