The Fetal Hepatocyte Phenotype and Cell-Based Therapy for Liver Disease

胎儿肝细胞表型和肝病细胞治疗

• 批准号: 9222004
• 负责人: Philip A. Gruppuso
• 金额: $ 34.74万
• 依托单位: RHODE ISLAND HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2019-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9222004
• 关键词: 1-Phosphatidylinositol 3-Kinase; Adult; Advanced Development; Area; Artificial Liver; Behavior; Biogenesis; Biological; Biology; Cell Cycle; Cell Cycle Progression; Cell Lineage; Cell Therapy; Cells; Characteristics; Chromatin Structure; Development; Device or Instrument Development; Disease; Embryo; Endothelial Cells; Engraftment; Epigenetic Process; Event; FRAP1 gene; Fetal Liver; Fetus; Gene Expression; Gene Expression Regulation; Genes; Genetic; Genome; Goals; Growth; Health; Hepatic; Hepatocarcinogenesis; Hepatocyte; Histones; Human; In Vitro; Injury; Laboratories; Leucine; Life; Liver; Liver diseases; Location; MAPK3 gene; Metabolic; Metabolic Diseases; Metabolism; Methods; Mitogens; Molecular; Newborn Infant; Nutrient; Pathway interactions; Peptide Hydrolases; Perinatal; Phenotype; Physiology; Population; Post-Translational Protein Processing; Pregnancy; Process; Rattus; Recovery; Regulation; Resistance; Ribosomes; Rodent; Role; Signal Pathway; Signal Transduction; Sirolimus; Testing; Translations; Transplantation; Variant; base; bile ductular; cell behavior; cell type; cholangiocyte; curative treatments; epigenetic regulation; fetal; fetus cell; in vivo; inhibitor/antagonist; injured; innovation; insight; liver cell proliferation; liver development; liver function; liver injury; mature animal; multipotent cell; novel; postnatal; public health relevance

DESCRIPTION (provided by applicant): Growth and functional differentiation of the liver are critical to late gestation fetal metabolism, the perinatal transition and metabolic adaptation by the newborn. The biology of fetal liver development also has implications for regulation of fetal somatic growth, hepatic carcinogenesis, and cell-based therapy for liver disease. Our laboratory has long focused on late gestation liver development in the rodent. In doing so, we have identified a fetal hepatocyte phenotype that is defined by the signaling pathways that regulate fetal hepatocyte growth, proliferation and gene expression. More recently, we demonstrated the ability of late gestation fetal rat liver cells possessing a key hepatocyte marker, leucine amino peptidase (LAP), to repopulate an injured adult liver. This is a capacity not shared by adult rat hepatocytes. The present proposal is based on the central hypothesis that histone variants and histone posttranslational modifications (PTMs), acting through effects on chromatin structure, account for the signaling phenotype of late gestation fetal rat hepatocytes and the persistence of this phenotype following transplantation into the adult liver microenvironment. The long term goal of the project is to identify genetic and epigenetic mechanisms that account for the novel characteristics of fetal liver cells, thereby applying an understanding of fetal liver development o the development of cell-based therapy for liver disease. This goal will be pursued through three Specific Aims. Specific Aim 1 is to identify a fetal hepatocyte epigenetic signature by examining chromatin structure, histone variants and histone PTMs in liver during late fetal versus adult life Specific Aim 2 is to characterize the functional relationship between histone variants, histone PTMs, chromatin structure and regulation of key growth-regulating genes in liver during the fetal to adult transition. This aim will test the hypothesis that specific histone variants and PTMs are associated with developmental changes in critical growth-regulating genes. In Specific Aim 3, we will assess the role of the epigenetic signature identified in Aims 1 and 2 in defining and maintaining the ability of late gestation fetal rat liver cells to repopulate an injured adult rat iver. This aim will test the hypothesis that a fetal hepatic epigenetic signature is characteristic of a subpopulation of fetal hepatocytes that possess both hepatocyte and bile ductular markers, and that this epigenetic signature is present both before transplantation and after engraftment. Completion of these aims will provide insight into molecular mechanisms that determine cell behavior in the developing liver while advancing the development of cell-based therapy for liver disease. The project is innovative in a number of aspects. We will generate new information regarding the epigenetic regulation of gene expression during liver development. In doing so, we will characterize a previously unidentified, multipotent cell population in fetal liver that can repopulate an injured adult liver. Finally, we will use innovative methods throughout these studies, thus advancing the ability to study epigenetic regulation in the context of mammalian developmental physiology.

描述（由申请人提供）：肝脏的生长和功能分化对于晚期妊娠胎儿代谢，新生儿的围产期过渡和代谢适应至关重要。胎儿肝发育的生物学也对调节胎儿体细胞生长，肝癌发生和基于细胞的肝病治疗有影响。我们的实验室长期以来一直关注啮齿动物的晚期妊娠肝发育。在这样做时，我们已经确定了一种胎儿肝细胞表型，该表型由调节胎儿肝细胞生长，增殖和基因表达的信号传导途径定义。最近，我们证明了妊娠胎儿大鼠肝细胞具有关键的肝细胞标记物，亮氨酸氨基肽酶（LAP）的能力，可以重新填充受伤的成年肝脏。这是成年大鼠肝细胞没有共同的能力。本提案基于以下中心假设：组蛋白变异和组蛋白后翻译后修饰（PTM），通过对染色质结构的影响作用，解释了晚期妊娠胎儿大鼠肝细胞的信号表型，以及该表型的持久性转移到成人肝微观条件中后这种表型的持久性。该项目的长期目标是确定解释胎儿肝细胞新特征的遗传和表观遗传机制，从而采用对胎儿肝脏发育的了解o基于细胞的肝脏疾病的发展。这个目标将通过三个特定目标来实现。具体目的1是通过检查晚期胎儿与成人生活特定目标2的染色质结构，组蛋白变异和组蛋白PTM来鉴定胎儿肝细胞表观遗传学特异性特异性目标2是表征组蛋白变异，组蛋白PTMS，组蛋白PTMS，染色剂PTMS，染色质素PTMS，染色剂结构，染色剂结构以及fe依成年基因的关键基因的调节。该目标将检验以下假设：特定的组蛋白变异和PTM与关键生长调节基因的发育变化有关。在特定的目标3中，我们将评估目标1和2在定义和维持晚期妊娠胎儿大鼠肝细胞重新填充受伤的成年大鼠IVER的能力方面所鉴定的表观遗传学特征的作用。该目标将检验以下假设：胎儿肝表观遗传学特征是具有肝细胞和胆汁导管标志物的胎儿肝细胞亚群的特征，并且这种表观遗传学特征在移植前和植入后都存在。这些目标的完成将提供对确定发育中肝脏细胞行为的分子机制的洞察力，同时推进基于细胞的肝病治疗的发展。该项目在许多方面都是创新的。我们将生成有关肝发育过程中基因表达的表观遗传调节的新信息。这样，我们将表征胎儿肝脏中先前未识别的多元细胞种群 重新填充受伤的成年肝脏。最后，我们将在整个研究中使用创新方法，从而提高在哺乳动物发育生理学的背景下研究表观遗传调节的能力。