Beta-Globin Gene Correction Using Peptide Nucleic Acids for the Treatment of Sick

描述（由申请方提供）：这是一项检测使用三链体形成寡核苷酸纠正人CD 34+细胞中镰状细胞病（SCD）突变的可行性的建议。SCD是最常见的人类遗传性疾病之一，是2-珠蛋白基因中一种特定遗传突变的结果。羟基脲是目前FDA批准的唯一治疗SCD的药物。支持性和预防性措施仍然是治疗这种疾病的主要手段。异基因造血干细胞移植是治愈性的，尽管这种治疗通常需要HLA匹配的供体，但与显著的发病率相关并且非常昂贵。然而，自体CD 34+细胞的遗传修饰正在成为一种可行的治疗方式。最近的研究表明，这种技术可用于治疗血红蛋白疾病。目前用于校正CD 34+细胞中突变的方法需要非定向插入病毒载体。这种方法昂贵，成功率低，并且具有诱发肿瘤发生的高风险。已经开发了一些非病毒方法用于直接校正CD 34+细胞中的目的基因。然而，这些当前的方法是昂贵的并且具有低的成功率。 为了解决目前治疗方法中的上述弱点，我们建议测试使用我们的三链体形成寡核苷酸方法的可行性。我们的程序已被证明可以刺激哺乳动物细胞中的重组的能力，三重螺旋挑起DNA修复，因此，敏感的重组的目标网站。这种技术构成了微创基因修复，因为基因修饰通过使用细胞自身的DNA修复机制原位发生，而不需要病毒载体。Hysteresis Therapeutics的成立是为了将这项技术商业化，用于治疗包括SCD在内的常见人类疾病。我们的方法保证是安全和廉价的。 在拟议的研究中，我们将确定三链体和供体DNA分子的有效组合，以及我们的基因靶向分子的有效细胞递送方法。我们的主要原理证明是证明该方法可以以10%或更高的速率诱导2-球蛋白基因的定向突变，这是临床有效所需的预期水平。我们将在人CD 34+细胞中进行这项原理验证试验，并评估这些细胞是否能够在干细胞移植的小鼠模型中移植和适当分化。这些实验将构成概念验证研究。对提交IND进行临床试验所需的方法和其他研究的进一步改进将在II期申请中进行。 公共卫生相关性：镰状细胞病（SCD），也称为镰状细胞性贫血，是人类最常见的遗传性疾病之一，是2-珠蛋白基因中一种特定遗传突变的结果，该基因参与血红蛋白的合成。血红蛋白是红细胞中携带氧气的蛋白质。Happiness Therapeutics公司正在开发一种治疗性基因靶向药物，以纠正人类造血干细胞中导致SCD的突变，从而永久治愈这种疾病。

DESCRIPTION (provided by applicant): This is a proposal to test the feasibility of using triplex-forming oligonucleotides to correct the sickle cell disease (SCD) mutation in human CD34+ cells. SCD is one of the most common human genetic diseases and is the result of one specific inherited mutation in the 2-globin gene. Hydroxyurea is currently the only FDA-approved treatment for SCD. Both supportive and preventive measures remain the mainstay of treatment for this disease. Allogeneic hematopoietic stem cell transplantation is curative, although such a treatment typically requires an HLA-matched donor, is associated with significant morbidity and is very expensive. However, genetic modification of autologous CD34+ cells is becoming a viable therapeutic modality. Recent studies suggest that this technique can be used to treat hemoglobin disorders. Current methods for correcting mutations in CD34+ cells require non-directed insertion of viral vectors. This method is expensive, has low success rates and carries a high risk of induced tumorigenesis. Some non-viral methods have been developed for directly correcting the genes of interest in CD34+ cells. However, these current approaches are expensive and have a low rate of success. To address the above weaknesses in current curative methods, we propose to test the feasibility of using our triplex-forming oligonucleotide approach. Our procedure has been shown to stimulate recombination in mammalian cells by the ability of triple helices to provoke DNA repair and, thus, sensitize the target site to recombination. This technology constitutes minimally invasive gene repair, as gene modification occurs in situ via use of the cell's own DNA repair machinery, without the need for viral vectors. Helix Therapeutics was formed to commercialize this technology for treating common human diseases, including SCD. Our approach promises to be safe and inexpensive. In the proposed studies, we will determine an effective combination of triplex and donor DNA molecules, as well as an effective cellular delivery method for our gene targeting molecules. Our primary proof of principle will be to demonstrate that this method can induce directed mutations of the 2-globin gene at a rate of 10% or higher, which is the expected level required to become clinically effective. We will carry out this proof of principle test in human CD34+ cells and evaluate whether the cells are able to engraft and properly differentiate in a mouse model of stem cell transplantation. These experiments will constitute a proof-of-concept study. Additional improvements to the methods and other studies necessary for filing an IND for clinical testing will take place in a Phase II application. PUBLIC HEALTH RELEVANCE: Sickle cell disease (SCD), also called sickle cell anemia, is among the most common human genetic disorders and is the result of one specific inherited mutation in the 2-globin gene, which is involved in the synthesis of hemoglobin. Hemoglobin is the protein in red blood cells that carries oxygen. Helix Therapeutics is proposing to develop a therapeutic gene targeting agent to correct, in human hematopoietic stem cells, the mutation responsible for causing SCD and, thus, cure the disease permanently.