Chemotherapy-free cure of hemoglobin disorders through base editing

通过碱基编辑无需化疗即可治愈血红蛋白疾病

基本信息

批准号：
10754114
负责人：
Daniel Evan Bauer
金额：
$ 80.77万
依托单位：
BOSTON CHILDREN'S HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-09-01 至 2027-05-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10754114
关键词：
Address Affect Allogenic Amino Acids Antigens Autologous Autologous Transplantation Biological Assay Bone Marrow Bone Marrow Purging Bypass Cell Transplantation Cells Clinic Clinical Clinical Trials Clustered Regularly Interspaced Short Palindromic Repeats Coupling Cytokine Receptors DNA Damage Data Defect Development Disease Drug Kinetics Endowment Engineering Engraftment Epitopes Erythroid Cells Extracellular Domain FLT3 gene Face Fetal Hemoglobin Future Gene Modified Gene Transfer Genetic Genetic Engineering Globin Goals Guide RNA Hair Hematological Disease Hematology Hematopoiesis Hematopoietic Hematopoietic Stem Cell Transplantation Hematopoietic stem cells Hemoglobin Hemoglobinopathies Homologous Transplantation Human IL3RA gene Immune Immunotherapy Immunotoxins Infection Infertility Infusion procedures Intervention Life Ligands Malignant Neoplasms Measurable Medical Modeling Modification Monoclonal Antibodies Mucositis Nature Nausea Parameter Estimation Pathologic Patients Pharmaceutical Preparations Physiological Pre-Clinical Model Production Radiation therapy Regimen Regulation Resistance Risk Sickle Cell Anemia Specificity System Testing Therapeutic Therapeutic antibodies Time Toxic effect Transfusion Translations Transplantation Treatment Efficacy Validation base editing beta Thalassemia cellular engineering chemotherapy chimeric antigen receptor T cells clinical efficacy conditioning curative treatments derepression efficacy validation gene therapy genome-wide genotoxicity hemoglobin B innovation manufacturing process new technology novel strategies nuclease preservation protein function receptor research clinical testing response scale up sickling stem cell engraftment tool

项目摘要

PROJECT SUMMARY Sickle cell disease (SCD) and transfusion-dependent b-thalassemia (TDT) are severe, prevalent blood disorders for which fetal hemoglobin (HbF) induction can bypass the fundamental hemoglobin defects and hematopoietic stem/progenitor cell (HSPC) transplantation (HSCT) offers curative potential. Allogeneic and autologous trans- plant approaches can succeed, nonetheless, the short- and long-term toxicities of genotoxic alkylating chemo- therapy-based conditioning regimens remain a substantial barrier to the widespread application of curative HSCT for SCD and TDT. Immunotherapies targeting HSPC antigens have been proposed as a safer conditioning strat- egy, however the pharmacokinetics of these agents currently hamper their clinical efficacy. The long-term goal of our proposal is to address this unmet medical need by developing an effective, novel strategy for the engraft- ment and progressive enrichment of autologous gene modified HSPCs in SCD and TDT by coupling non-geno- toxic immunotherapy-based myeloablation with epitope-engineering. Our central hypothesis is that precise multiplexed base editing of HbF determinants and targeted epitopes within HSPCs can endow hematopoietic lineages with both HbF induction capacity and selective resistance to monoclonal Abs or CAR-T cells without affecting protein function or regulation (so-called stealth status). We have identified defined minimal amino-acid changes within the extracellular domains (ECD) of the cytokine receptors KIT, FLT3 and IL3RA, each expressed in long-term repopulating HSCs, that abrogate recognition by therapeutic Abs while preserving physiologic responses to stimulation with their respective ligands. Here, we will capitalize on these results and further expand the reach of these innovative genetic engineering tools with the objectives to i) generate “stealth” g-globin derepressed HSPCs by multiplex CRISPR-Cas base-editing; ii) validate efficacy of this approach on suitable pre-clinical models of b-hemoglobinopathy, and iii) further optimize and scale the manufacturing process for production of efficiently and precisely engineered cellular products suitable to progress to the clinic. We aim: 1) to optimize multiplex base editing approaches to simultaneously derepress HbF and engineer stealth HSPC epitopes that will generate immunotherapy resistant hematopoietic stem cells capable of ameliorating sickling and globin chain imbalance in SCD and TDT patient erythroid cells; 2) to maximize the engraftment of edited HSCs by optimizing immunotherapy regimens to enrich multiplex edited HSPCs through modeling parameters for therapeutic selection of edited HSPCs, and thereby obtaining proof-of-concept chemotherapy-free engraft- ment and selection of edited patient HSPCs; and 3) to identify conditions that produce efficient on-target base edits without measurable off-targets at clinical scale. This project will provide fundamental advancement of a new chemotherapy-free gene therapy approach to HSCT for hemoglobinopathies that should additionally have broad applicability to other hematopoietic disorders.

项目摘要镰状细胞疾病（SCD）和依赖于输血的B-心中贫血（TDT）严重，流行的血液疾病胎儿血红蛋白（HBF）诱导可以绕过基本血红蛋白缺陷和造血茎/祖细胞（HSPC）移植（HSCT）具有治疗潜力。同种异体和自体反式尽管如此，植物的方法仍可以成功，尽管如此基于治疗的调节方案仍然是治疗性HSCT宽度应用的实质性障碍对于SCD和TDT。已经提出针对HSPC抗原的免疫疗法作为更安全的条件层但是，这些药物的药代动力学目前妨碍了其临床效率。长期目标我们的建议是通过制定有效的新型策略来满足这种未满足的医疗需求。通过耦合非生物 - 基于毒性免疫疗法的骨髓疗法和表位工程。我们的核心假设是如此精确 HBF确定剂和HSPC中的靶向表位的多路复用基础编辑可以赋予造血具有HBF诱导能力和对单克隆ABS或CAR-T细胞的选择性抗性的谱系影响蛋白质功能或调节（所谓的隐形状态）。我们已经确定了定义的最小氨基酸细胞因子受体试剂盒（FLT3和IL3RA）的细胞外域（ECD）内的变化，每个都表达在长期重新流传的HSC中，可以通过治疗ABS消除识别性的识别对刺激的反应与各自的配体。在这里，我们将利用这些结果并进一步扩展这些创新的基因工程工具的影响通过多重CRISPR-CAS基础编辑的hspcs抑制了HSPC； ii）验证这种方法的效率 B-杂型细胞病的临床前模型和iii）进一步优化和扩展制造过程有效，精确地设计的细胞产品适合于诊所进行。我们的目标：1）优化多重基础编辑方法以简单地解开HBF和工程师隐形HSPC 将产生免疫疗法的抗造血干细胞的表位，能够改善病态 SCD和TDT患者红细胞细胞中的球蛋白链失衡； 2）最大化编辑的植入通过优化免疫疗法方案，通过建模参数来丰富多重HSPC来丰富HSC 用于对编辑的HSPC进行热选择，从而获得概念验证的无化疗植入编辑的患者HSPC的精神和选择； 3）确定产生有效靶向基础的条件在临床规模上没有可测量的脱离目标的编辑。该项目将提供一个基本进步新的无化学疗法基因治疗方法用于血红蛋白病的HSCT 对其他造血疾病的广泛适用性。