Using human ESCs as a genetic model for PNH and other blood diseases

描述（由申请人提供）：阵发性夜间血红蛋白尿（PNH）是一种造血干细胞（hsc）获得猪- a基因突变的克隆性疾病。克隆猪-a突变在几乎所有的PNH专利测试中被发现，导致所有gpi锚定蛋白（GPI-APs）在受影响的造血干细胞和所有衍生的造血后代中缺乏。尽管有证据表明PNH的生化和分子机制已经很好地阐明，但PNH患者中猪- a突变克隆优势的机制以及PNH与其他骨髓衰竭疾病如再生障碍性贫血（AA）和骨髓增生异常综合征（MDS）的密切关系仍不清楚。在临床特征出现之前的早期阶段监测患者的猪- a突变是不可能的。目前，在健康志愿者的人类造血干细胞中产生猪-a突变是不可行的，而现有的缺乏GPI-APs的猪-a缺失小鼠在血液细胞并没有复制病人的PNH症状。这项研究的长期目标是了解GPI-APs在骨髓衰竭综合征和造血中的作用。针对PA-05-013，一种基于人造血干细胞的[nih批准，WA01(H1)]，本文提出了一种前瞻性实验系统来研究猪-a /GPI-AP缺乏对人造血细胞的影响。将使用nih批准的含有诱导的猪-a突变和GPI-AP缺陷的人类ESC，并使用最近开发的人类ESC启动的造血系统检查猪-a /GPI-AP缺陷的影响。该项目的成功完成也可能为研究正常和异常的人类造血和造血干细胞提供一种新的遗传模型。进一步了解猪- a /GPI-AP缺乏症在人类造血和造血干细胞中的作用，将有助于我们改进和开发新的治疗PNH和其他相关血液疾病如AA和MDS的方法。

DESCRIPTION (provided by applicant): Paroxysmal Nocturnal Hemoglobinuria (PNH) is a clonal disorder of hematopoietic stem cells (HSCs) acquiring mutations in the PIG-A gene. Clonal PIG-A mutations are found in nearly all PNH patents tested resulting in the lack of all GPI-anchored proteins (GPI-APs) in affected HSCs and all the derived hematopoietic progeny. Despite evidences that the biochemical and molecular mechanisms for PNH have been brilliantly elucidated, mechanisms of PIG-A mutant clonal dominance in PNH patients and the close relationship of PNH to other marrow failure diseases such as aplastic anemia (AA) and myelodysplasia syndrome (MDS) are still unknown. Monitoring the PIG-A mutations in patients is impossible at early stage before the onset of clinical features. Creating a PIG-A mutation in human HSCs from healthy volunteers is not feasible currently and existing Pig-a null mice lacking GPI-APs in. blood cells have not replicated the PNH symptoms seen in patients. The lone term objective of this research is understanding effects of GPI-APs in bone marrow failure syndrome and hematopoesis. In response to PA-05-013, a human ESC-based [NIH-approved, WA01(H1)], prospective experimental system is proposed here to investigate effects of the PIG-A/GPI-AP deficiency in human hematopoietic cells. The NIH-approved human ESC that contain an induced PIG-A mutation and are GPI-APs deficient will be used, and effects of PIG-A/GPI-AP deficiency using human ESC-initiated hematopoiesis systems recently developed will be examined. The successful completion of this project may also provide a novel genetic model to investigate normal and abnormal human hematopoiesis and HSCs. Improved understanding of PIG-A/GPI-AP deficiency in human hematopoiesis and HSCs will in turn help us to improve and develop new treatments for PNH and other related blood diseases such as AA & MDS.