Formation of endocrine pancreas progenitors

描述(申请人提供)：1型糖尿病的细胞治疗方法主要集中在单个或多个转录因子的表达上，这些转录因子可以驱动(细胞特定的基因表达模式)，并且大多数至少部分依赖于Pdx1，这是一种在胰腺早期发育和成熟(细胞)中具有关键调节作用的同源结构域转录因子，以及Ngn3，它是一种关键的促内分泌转录因子，其瞬时表达的特点是内分泌前体细胞。无论这些方法多么有希望，通过这些方法获得细胞表型的效率仍然很低，这些努力的保真度和稳定性还没有得到充分的评估。虽然内胚层的实现是可重复和有效的，但随后的转变，如从胰腺前体细胞到内分泌胰腺前体细胞的转变，效率特别低。我们最近发现，Pdx1通过与Hnf6共同直接调节Ngn3，以及在胰腺发育早期参与交叉调节的转录因子网络，对小鼠内分泌祖细胞的规范起到了作用。我们假设，了解转录因子Ngn3的表观遗传调控以及Pdx1和Hnf6在发展中(细胞)的交叉调控转录因子网络中的作用，将有助于努力提高(细胞表型的效率、保真度和稳定性，通过引导非(细胞群体的分化实现)。因此，我们在目标1中提出：研究Ngn3在人胰腺前体细胞中的遗传和表观遗传调控；在目标2中，分析Pdx1和Hnf6在促进内分泌前体细胞规范方面的遗传和分子相互作用；在目标3中，通过全局占位和基因表达分析，确定Pdx1和Hnf6在内分泌前体细胞转录网络中的作用。最重要的长期目标是利用从这些研究中获得的信息来优化ES和iPS细胞，可能还有成熟的谱系，向(细胞命运)的引导过渡。 公共卫生相关性：人们对1型糖尿病的细胞治疗寄予厚望，但人类胰岛移植的可获得性和短期功能有限，导致人们强烈关注(？细胞)的替代来源。拟议研究的首要目标是优化ES和iPS细胞向(细胞命运)的引导过渡，使潜在的患者特异性(细胞)可用于移植。

DESCRIPTION (provided by applicant): Approaches to cell based therapies for type 1 diabetes have largely focused on the expression of a single or a combination of transcription factors that can drive ( cell specific patterns of gene expression, and most have relied at least in part on Pdx1, a homeodomain transcription factor with critical regulatory roles in early pancreas development and in the mature ( cell, and on Ngn3, a critical pro-endocrine transcription factor whose transient expression characterizes endocrine progenitors. However promising, the efficiency of achieving a ( cell phenotype by any of these approaches remains low, and the fidelity and stability of these efforts have not been fully evaluated. Although endoderm is achieved reproducibly and efficiently, subsequent transitions, such as from pancreatic progenitor to endocrine pancreatic progenitor, are achieved with particularly low efficiency. We recently determined that Pdx1 contributes to specification of endocrine progenitors in mice both by regulating Ngn3 directly in concert with Hnf6 and by participating in a cross-regulatory transcription factor network during early pancreas development. We hypothesize that understanding the epigenetic regulation of the transcription factor Ngn3 and the roles of Pdx1 and Hnf6 in the cross-regulatory transcription factor network of developing ( cells will inform efforts to improve the efficiency, fidelity and stability of the ( cell phenotype achieved through the guided differentiation of non-( cell populations. Therefore, we propose in AIM 1: To examine the genetic and epigenetic regulation of Ngn3 in human pancreas progenitors, in AIM 2: To analyze the genetic and molecular interactions between Pdx1 and Hnf6 in promoting endocrine progenitor specification, and in AIM 3: To define the role of Pdx1 and Hnf6 in the transcriptional network of endocrine pancreas progenitors through global occupancy and gene expression analysis. The overarching long-term goal is to utilize this information gained from these studies to optimize the guided transition of ES and iPS cells, and possibly mature lineages, toward a ( cell fate. PUBLIC HEALTH RELEVANCE: The high hopes for cell based therapy for type 1 diabetes have been tempered by the limited availability and short-term function of human islets for transplantation, leading to intense focus on alternate sources of (?cells. The overarching goal of the proposed studies is to optimize the guided transitions of ES and iPS cells toward a ( cell fate to make potentially patient-specific ( cells available for transplantation.