Olfactory Epithelial Stem Cell Regulation by the Transcription Factor p63

转录因子 p63 对嗅觉上皮干细胞的调节

• 批准号: 8090384
• 负责人: Nikolai Schnittke
• 金额: $ 3.76万
• 依托单位: TUFTS UNIVERSITY BOSTON
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-01 至 2014-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8090384
• 关键词: Address; Adult; Age; Alleles; Animals; Anosmia; Appearance; Automobile Driving; Basal Cell; Basement membrane; Biochemical; Biological Assay; Breeding; Cell Differentiation process; Cell Maintenance; Cell Proliferation; Cell physiology; Cells; Clinic; Commit; Complex; Data; Development; Disease model; Duct (organ) structure; Embryo; Embryonic Development; Environment; Epidermis; Epithelial; Epithelium; Exhibits; Exposure to; Family; Future; Gases; Generations; Genetic; Genetic Recombination; Gland; Goals; Hour; Human; Infection; Injury; Knock-out; Knockout Mice; LacZ Genes; Lesion; Life; Location; Maintenance; Mediating; Membrane; Methods; Multipotent Stem Cells; Mus; Natural regeneration; Nature; Neurons; Olfactory Epithelium; Patients; Pattern; Peripheral; Phenotype; Population; Population Heterogeneity; Preclinical Drug Evaluation; Process; Proliferating; Protein Isoforms; Recovery of Function; Regenerative Medicine; Regulation; Reporter; Research; Retroviridae; Role; Smell Perception; Staging; Stem cells; Supporting Cell; System; Tamoxifen; Testing; Therapeutic; Therapeutic Uses; Time; Tissues; Transgenic Mice; Transgenic Organisms; Work; adult stem cell; base; cell type; genetic manipulation; member; methyl bromide; mutant; nerve stem cell; neuron component; postnatal; progenitor; promoter; public health relevance; receptor binding; recombinase; regenerative; repaired; research study; retroviral transduction; stem; stem cell biology; stem cell population; transcription factor; transdifferentiation

DESCRIPTION (provided by applicant): The mammalian olfactory epithelium (OE) is able to regenerate its cellular components (neurons, supporting cells, and duct/gland cells) throughout adult life under normal, maintenance conditions, as well as regenerative conditions after destruction of all differentiated cell types by exposure to the gas methyl bromide (MeBr). This ability together with its peripheral and therefore accessible location makes the OE an attractive system to utilize for purposes of regenerative medicine. Before such a potential can be realized one must first perform a complete structural, biochemical, and functional characterization of the cellular dynamics of the OE. At least two distinct populations of putative stem or progenitor cells have been identified among the basal cells of the epithelium that may be responsible for its regenerative capacity. Globose Basal Cells (GBCs) constitute a heterogeneous population of lineage committed and uncommitted progenitors situated below (basal to) the neuronal layer of the epithelium. Horizontal Basal Cells (HBCs) lie in the basalmost layer of the OE and correspond to an apparently homogeneous, layer of cells in tight contact with the basement membrane of the OE. Both of these basal cell types have been shown by various methods to have the ability to generate all the differentiated cell types of the OE, however HBCs are not present until late in embryonic development whereas GBCs are the progenitor cells involved in the embryonic assembly of the tissue. The transcription factor p63, a member of the p53 family, is necessary for the embryonic appearance of HBCs and loss of p63 expression in the adult regenerative environment appears to be correlated with the ability of HBCs to give rise to differentiated OE cell types. The goal of the proposed research is to exhaustively characterize the functional role of p63 in HBC generation, quiescence, activation, and transdifferentiation. First, nascent HBCs that express p63 but have not yet differentiated toward the HBC phenotype will be characterized based on expression of other markers previously identified in the lab as OE progenitor cell markers. Next, the sufficiency of p63 expression in HBC generation will be probed by forcing expression of p63 in the regenerative environment via retroviral infection. Finally the role of p63 loss will be assessed in the adult normal and post-lesion settings, via a conditional knock-out genetic approach. These studies will go a long way toward elucidating the nature of context dependent plasticity present in the OE specifically and adult stem cell systems in general, as well as provide a mechanistic framework in which to approach the therapeutic application of these cells. PUBLIC HEALTH RELEVANCE: In the course of human ageing, HBCs are one of the last cell types remaining in the olfactory epithelium even in patients with anosmia (loss of the sense of smell). The experiments proposed here will elucidate the mechanisms of HBC plasticity which could be utilized in the clinic either to activate these cells directly for regenerative medicine applications, or to obtain a patient specific activatable stem cell population for disease modeling and drug screening.

描述（由申请人提供）：哺乳动物嗅觉上皮（OE）能够在正常，维持条件下以及通过暴露于所有差异化细胞类型后，在正常的维持条件下，在正常的维持条件下整个成人生活中的细胞成分（神经元，支持细胞和导管/腺细胞）再生其细胞成分（神经元，支持细胞和导管/腺细胞）。这种能力及其周围位置，因此可进入的位置使OE成为用于再生医学目的的有吸引力的系统。在实现这种潜力之前，必须首先执行OE细胞动力学的完整结构，生化和功能表征。在上皮的基底细胞中已经发现了至少两个不同的假定茎或祖细胞种群，可能是其再生能力负责的。球糖基底细胞（GBC）构成了位于上皮细胞神经元层（基础至基础）下方的谱系的异质种群。水平基底细胞（HBC）位于OE的最大层中，对应于与OE基底膜紧密接触的明显均匀的细胞层。这两种基础细胞类型已经通过各种方法显示出具有生成所有分化细胞​​类型的能力，但是直到胚胎发育后期才存在HBC，而GBC是涉及组织胚胎组装的祖细胞。转录因子p63是p53家族的成员，对于HBC的胚胎出现和在成人再生环境中p63表达的丧失似乎与HBC引起分化的OE细胞类型的能力相关。拟议的研究的目的是详尽地表征p63在HBC生成，静止，激活和跨分化中的功能作用。 首先，根据先前在实验室中以OE祖细胞标记物为OE祖细胞标记的其他标记的表达来表征，表达p63但尚未将其分化为HBC表型的新生HBC将被表征。接下来，通过通过逆转录病毒感染强迫p63在再生环境中p63的表达来探测p63表达的充分性。最后，将通过条件敲除遗传方法在成人正常和静脉内设置中评估p63损失的作用。这些研究将大有帮助阐明OE中存在的依赖性可塑性的性质和一般的成年干细胞系统，并提供了一个机械框架，可以在其中接近这些细胞的治疗应用。 公共卫生相关性：在人类衰老的过程中，HBC是嗅觉上皮的最后一种细胞类型之一，即使在厌食症患者中（嗅觉失去）也是如此。此处提出的实验将阐明HBC可塑性的机制，该机制可以在诊所中用于直接激活这些细胞以进行再生医学应用，或者获得特定于患者的可激活干细胞种群进行疾病建模和药物筛查。