iPS-derived hepatocytes for interrogation of lipid phenotypes

描述(由申请人提供)： 血浆脂类(低密度脂蛋白-C、高密度脂蛋白-C和甘油三酯)是动脉粥样硬化性心血管疾病的重要危险因素，已被证明是全基因组关联研究的沃土。全球脂类遗传学联合会，一个总共约100,000名受试者的脂类GWA联盟，已经确定了总共95个与至少一个血脂性状显著相关的全基因组基因座。虽然这份清单包括了大多数已知的导致孟德尔人脂质紊乱的基因，但大多数基因以前并不与脂蛋白代谢有关。确定这些遗传位点如何影响与脂肪代谢相关的人类组织类型的表型是关键，尤其是肝脏。这将有助于更好地了解脂蛋白代谢的生理调节，并找到降低低密度脂蛋白和甘油三酯，提高高密度脂蛋白胆固醇的新的治疗靶点。为了研究基因影响肝细胞脂质生物学和血脂特性的细胞机制，有必要建立具有特定基因的患者的无限可再生的功能性肝细胞来源。我们已经开发出使用脂肪干细胞(ASCs)作为获得重新编程的诱导多能干细胞(IPS)的基础的能力，并拥有一个致力于分离ASC和扩大iPS生成的核心。通过宾夕法尼亚大学和威斯康星医学院的合作，我们已经建立了将人类iPS细胞分化为肝细胞的方案。我们的研究团队由iPS生成、肝细胞生成和肝细胞脂代谢方面的专家组成。我们将开发一个从300多名具有特定基因型别的受试者中获得iPS细胞系和iPS来源的肝细胞的文库，并将使用它们来(1)开发高效和可靠的方案来从ASCs获得iPS细胞系，然后分化为有功能的肝细胞；(2)扩大这些方案的规模，以实现iPS细胞系和肝细胞的高通量生成；以及(3)从这些肝细胞进行代谢谱分析。这些研究应该为影响脂蛋白代谢的一些最有说服力的血浆脂质性状的GWA基因座的分子机制提供新的见解。(摘要结束)

DESCRIPTION (provided by applicant): Plasma concentrations of lipids (LDL-C, HDL-C and triglycerides) are important risk factors for atherosclerotic cardiovascular disease and have proven fertile territory for genome-wide association studies (GWAS). The Global Lipids Genetics Consortium, a consortium of lipid GWAS totaling approximately 100,000 subjects, has identified a total of 95 loci that are genome-wide significantly associated with at least one plasma lipid trait. While this list includes most of the genes that are known causes of Mendelian lipid disorders, the majority are not previously associated with lipoprotein metabolism. It is key to determine how these genetic loci affect phenotypes in human tissue types relevant to lipid metabolism, especially the liver. This will lead to a greater understanding of the physiological regulation of lipoprotein metabolism and identify novel therapeutic targets for reducing LDL-C and TG and raising HDL-C. There is a need to establish infinitely renewable sources of functional hepatocytes from patients with defined genotype in order to study the cellular mechanisms by which genotype influences hepatocyte lipid biology and plasma lipid traits. We have developed the ability to use adipose stem cells (ASCs) to serve as the basis for obtaining reprogrammed induced pluripotent stem (iPS) cells and have a core dedicated to both ASC isolation and to scaling up iPS generation. Through collaboration between Penn and Medical College of Wisconsin we have established protocols for the differentiation of human iPS cells into hepatocytes. Our consortium comprises investigators expert in iPS generation, hepatocyte generation, and hepatocyte lipid metabolism. We will develop a library of iPS cell lines and iPS-derived hepatocytes from ~300 hundred subjects with defined genotypes and will use them to (1) develop highly efficient and reliable protocols to obtain iPS cell lines from ASCs, followed by differentiation into functional hepatocytes; (2) scale up these protocols to enable high- throughput generation of iPS cell lines and hepatocytes; and (3) perform metabolic profiling from these hepatocytes. These studies should provide novel insights into the molecular mechanisms by which some of the most compelling GWAS loci for plasma lipid traits influence lipoprotein metabolism. (End of Abstract)