Targeted conditioning to maximize prenatal HSC engraftment for SCD

针对性调节以最大限度地提高 SCD 的产前 HSC 植入

• 批准号: 10654382
• 负责人: Graca Duarte Almeida-Porada
• 金额: $ 71.66万
• 依托单位: WAKE FOREST UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10654382
• 关键词: ALCAM gene; Achievement; Acute; Acute Disease; Adult; Allogenic; Animal Model; Animals; B-Lymphocytes; Biological Models; Birth; Blood; CD34 gene; Cell Separation; Cells; Characteristics; Child; Chronic; Chronic Disease; Clinical; Clustered Regularly Interspaced Short Palindromic Repeats; Communities; Development; Dipeptidyl-Peptidase IV; Disease; Disease model; Electrophoresis; Engraftment; Exhibits; Fetal Development; Fetal Hemoglobin; Fetal Sheep; Fetus; Genes; Genetic Diseases; Goals; Head; Hematological Disease; Hematopoietic Cell Growth Factors; Hematopoietic Stem Cell Transplantation; Hematopoietic Stem Cell subsets; Hematopoietic stem cells; Hemoglobin; Hemoglobinopathies; Homing; Human; IL2RG gene; Immune; Incidence; Infant; Infection; Inherited; Intervention; Life; Medical; Modeling; Monitor; Mus; Mutation; NCAM1 gene; Natural Killer Cells; Nature; Other Genetics; Pain; Patients; Pattern; Peptide Hydrolases; Phenotype; Play; Population Study; Procedures; Proto-Oncogene Protein c-kit; Resistance; Resources; Risk; Role; Sheep; Sheep Diseases; Sickle Cell; Sickle Cell Anemia; Solubility; Stroke; Stromal Cell-Derived Factor 1; Symptoms; T-Lymphocyte; Testing; Therapeutic; Time; Treatment Efficacy; World Health Organization; acute chest syndrome; antibody conjugate; beta Globin; clinically relevant; compliance behavior; conditioning; curative treatments; disease phenotype; economic implication; efficacy testing; fetal; fetal immunity; human disease; in utero; in utero transplantation; infancy; knock-down; lung injury; novel; novel strategies; novel therapeutic intervention; novel therapeutics; prenatal; sheep model; sickle cell crisis; sickling; side effect; small hairpin RNA; somatic cell nuclear transfer; statistics; stem cell engraftment; stressor; success; therapeutic evaluation; translational model

PROJECT ABSTRACT: Treatment of genetic disorders by in utero transplantation (IUTx) has safely been performed for decades in humans. The first IUTx cure, in the US, used hematopoietic stem cells (HSC) and corrected a child with X-SCID. Since this groundbreaking moment >25 yrs. ago, >50 patients have now been treated with this procedure for 14 different genetic disorders. However, for reasons that are still not well understood, full therapeutic success has only been achieved in X-SCID patients. Thus, a better understanding of the mechanisms by which HSC engraftment is hindered after IUTx is required, so that strategies can be developed to achieve therapeutic levels of HSC engraftment in other genetic disorders, such as hemoglobinopathies, that could benefit from IUTx. We and others have identified several characteristics of the developing fetus that may negatively impact its ability to serve as an amenable HSC recipient. Among these factors are competition from highly proliferative host HSC, more significant fetal immune barriers than initially known, and the degree of maturity and receptivity of nascent BM niches required for engraftment of donor (adult) HSC. Here, using fetal sheep as a model, we propose to: (Aim1) define the nature of, and overcome, the barriers to engraftment by using non-genotoxic conditioning to dissect the role that niche availability, host HSC competition, and fetal immunity play in the engraftment of adult donor HSC following IUTx, and (Aim 2) determine the impact of the phenotype and functionality of the donor HSC on the levels of engraftment following IUTx. We hope that, upon completion of these first 2 Aims, we will not only have identified the mechanisms involved in resistance to HSC engraftment, but we will also have achieved a minimum target of 20-25% HSC engraftment, which would allow IUTX to become a viable therapeutic approach for hemoglobinopathies. Among these, sickle cell disease (SCD) is the most common inherited blood disorder in the US, and one of the diseases that could benefit from IUTx, since even though the fetus is protected from sickling by the presence of fetal hemoglobin (Hb), clinical manifestations of SCD start during early infancy, placing the child at risk of complications such as stroke, splenic crisis, pain episodes, life-threatening infections, and episodes of acute chest syndrome, which can cause permanent lung damage. Of direct relevance to SCD, sheep exhibit the same developmental pattern of fetal to adult Hb switching as humans. Recently, using CRISPR/ Cas editing and subsequent somatic cell nuclear transfer, we produced SCD sheep with a disease phenotype mirroring that of human patients, displaying sickled cells in blood smears, positive Hb solubility test, and HbS detected by Hb electrophoresis. In Aim 3, we propose to validate the sheep SCD model by monitoring the animals over time, determining the stressors that induce sickle cell crises, and defining acute and chronic disease complications. In addition, we will test the therapeutic efficacy of IUTx for treating/curing SCD. Upon completion, we hope these studies will contribute to the development of novel strategies to achieve curative levels of HSC engraftment after IUTX and will validate a highly clinically relevant model for the SCD community in general.

项目摘要： 在子宫移植中对遗传疾病的治疗（IUTX）已经安全地进行了数十年 人类。在美国，第一种IUTX治愈方法使用造血干细胞（HSC），并用X-SCID纠正了儿童。 由于这个开创性的时刻> 25年。以前，> 50名患者现在接受了14例手术治疗 不同的遗传疾病。但是，由于仍然不太了解的原因，完全的治疗成功已有 仅在X-SCID患者中实现。因此，更好地理解了HSC的机制 需要在IUTX之后阻碍植入，因此可以制定策略以达到治疗水平 其他遗传疾病（例如血红蛋白病）中的HSC植入可能会受益于IUTX。我们 其他人已经确定了发育中的胎儿的几个特征，这些特征可能会对其的能力产生负面影响 充当正式的HSC收件人。这些因素包括来自高度增殖的宿主HSC的竞争， 比最初已知的更明显的胎儿免疫屏障，以及新生的成熟度和接受程度 捐赠者（成人）HSC所需的BM壁ni。在这里，使用胎儿绵羊作为模型，我们建议： （AIM1）通过使用非生物毒性调节来定义并克服植入障碍的性质 剖析利基可用性，宿主HSC竞争和胎儿免疫在成人植入中的作用 IUTX之后的供体HSC，（AIM 2）确定表型和功能的影响 HSC在IUTX之后的植入水平。我们希望，在完成前两个目标后，我们将 不仅确定了抗HSC植入抗性的机制，而且我们还将有 达到20-25％HSC植入的最低目标，这将使IUTX成为可行的治疗 血红蛋白病的方法。其中，镰状细胞病（SCD）是最常见的血液 在美国的疾病，以及可能从IUTX中受益的一种疾病，因为即使胎儿受到保护 由于胎儿血红蛋白（HB）的存在，SCD的临床表现在婴儿早期开始时开始 使孩子面临并发症的风险，例如中风，脾危机，疼痛发作，威胁生命的感染， 以及急性胸部综合征的发作，可能导致永久性肺部损伤。与SCD的直接相关性， 绵羊表现出与人类相同的成人HB转换的发育模式。最近，使用crispr/ CAS编辑和随后的体细胞核转移，我们生产了具有疾病表型的SCD绵羊 反映人类患者的患者，在血液涂片中显示镰状细胞，HB溶解度阳性和HBS 通过HB电泳检测。在AIM 3中，我们建议通过监视绵羊SCD模型来验证绵羊SCD模型 随着时间的流逝，动物确定引起镰状细胞危机的压力源，并定义急性和慢性病 并发症。此外，我们将测试IUTX治疗/固化SCD的治疗功效。完成后， 我们希望这些研究将有助于发展新型策略以达到HSC的治疗水平 IUTX之后的植入物，将为SCD社区验证一个高度临床相关的模型。