Immunodeficient FAH-/- Pigs

免疫缺陷 FAH-/- 猪

基本信息

批准号：
8943130
负责人：
SCOTT L NYBERG
金额：
$ 40.2万
依托单位：
MAYO CLINIC ROCHESTER
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-07-08 至 2020-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8943130
关键词：
Address Animal Model Animals Cell Therapy Cell Transplantation Cell Transplants Cells Dependence Development Disease Donor person Engraftment Environment Enzymes Family suidae Fibroblasts Foundations Fumarylacetoacetase Genes Genetic Genetic Engineering Genetic Recombination Health Status Hepatocyte Hepatocyte transplantation Homozygote Human Immune Immune response Immunologic Deficiency Syndromes Immunosuppression Inborn Errors of Metabolism Inborn Genetic Diseases Inherited Injection of therapeutic agent Knock-out Life Liver Measures Mediating Metabolic Diseases Methodology Modeling Mus Mutation Normal Cell Patients Phenotype Production Property Protective Agents Research Residual state Techniques Teratoma Time Transplantation Tyrosine Metabolism Pathway Tyrosinemias Withdrawal base clinical application design fetal gene therapy in utero in utero transplantation in vivo individualized medicine induced pluripotent stem cell liver metabolism mutant novel postnatal preclinical study prevent public health relevance research study somatic cell nuclear transfer stem

项目摘要

DESCRIPTION (provided by applicant): Hepatocyte transplantation has been proposed as a cellular therapy for patients with inherited metabolic disorders of the liver. However, hepatocyte transplantation has several shortcomings that limit its clinical application. These limitations include a shortage and inconsistent supply of transplantable hepatocytes and a life-long dependence on immunosuppression after transplantation. We hypothesize that screenable inborn errors of metabolism, such as Hereditary Tyrosinemia Type 1 (HT1), can be treated by an individualized approach involving ex vivo gene therapy and in vivo cell transplantation. Our approach is individualized since the patient's own cells may be used in the treatment. In our initial proof of concept studies, mature human hepatocytes and less mature hepatocyte-like cells derived from human induced pluripotent stem (iPS) cells will be evaluated. These human cells will be expanded in a novel, genetically engineered large animal (pig) possessing homozygote mutations of two genes: 1) fumarylacetoacetate hydrolase (FAH-/-), the enzyme that catalyzes the final step in tyrosine metabolism; 2) recombination activating gene 2 (RAG2-/-) to produce severe immunodeficiency. FAH deficiency causes functional instability in effected hepatocytes and results in a selective milieu for robust expansion of normal (FAH+) donor hepatocytes. Rejection of FAH+ human cells in immunodeficient FAH-/- RAG2-/- pigs will be further prevented by fetal tolerization, transplanting donor cells in utero prior to immune development. We postulate that in utero cell transplantation will also provide a more natural fetal environment for differentiation of iPS-derived hepatocyte-like cells. One or more injection(s) of donor cells wll be performed postnatally to enhance engraftment. Tapered use of the protective drug, 2-nitro-4-trifluoromethylbenzoyl-1,3- cyclohexanedione (NTBC), will allow robust expansion of transplanted cells in FAH- deficient pigs. These proof-of-concept studies performed in a large animal model of HT1 will provide a foundation for hepatocyte transplantation as an individualized treatment of screenable inborn errors of liver metabolism.

描述（通过应用提供）：已提出肝细胞移植作为肝脏遗传代谢疾病患者的细胞疗法。但是，肝细胞移植有几个缺点，这些缺点限制了其临床应用。这些局限性包括移植肝细胞的短缺和不一致的供应以及移植后对免疫抑制的终身依赖。我们假设可以通过涉及离体基因治疗和体内细胞移植的个性化方法来治疗新陈代谢的可筛查原本本质错误，例如遗传性酪氨酸1（HT1）。我们的方法是个性化的，因为患者自己的细胞可用于治疗。在我们最初的概念研究证明中，将评估成熟的人肝细胞和不太成熟的肝细胞样细胞，这些细胞将衍生自人类诱导的多能茎（IPS）细胞。人类细胞将在具有两个基因的纯合突变的新型大型动物（PIG）中扩展：1）富马利乙酰乙酸水解酶（FAH - / - ），该酶是催化酪氨酸代谢的最后一步的酶； 2）重组激活基因2（rag2 - / - ）产生严重的免疫缺陷。 FAH缺乏会导致功能不稳定的肝细胞中的功能不稳定性，并为正常（FAH+）供体肝细胞的稳健扩张带来选择性环境。 FAH+人类细胞在免疫缺陷的FAH - / - rag2 - / - 猪中的排斥将通过胎儿耐受，在免疫发育前将供体细胞移植在子宫内。我们假设在子宫细胞移植中还将为IPS衍生的肝细胞样细胞的分化提供更自然的胎儿环境。在产后进行一种或多种注射供体细胞以增强植入。受保护药物的锥形使用2-硝基-4-三氟甲基苯甲酰基-1,3-环己二酮（NTBC），将允许在缺乏猪的FAH猪中强烈扩展移植细胞。这些在大型HT1动物模型中进行的概念验证研究将为肝细胞移植提供基础，作为对肝脏代谢的可筛查先天误差的个性化处理。