Hematopoietic gene therapy for hemophilia A

甲型血友病的造血基因治疗

基本信息

批准号：
8434878
负责人：
Christopher Bradley Doering
金额：
$ 36.89万
依托单位：
EMORY UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-04-01 至 2015-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8434878
关键词：
A Mouse Affect Anabolism Antibodies Biology Biomedical Engineering Blood Blood Cells Blood Clot Blood Coagulation Factor Blood coagulation Bone Marrow Transplantation CD34 gene Cell Lineage Cells Clinical Clinical Trials Data Development Disease Drug Kinetics Engraftment Factor VIII Family suidae Gene Mutation Gene Transfer Genetic Genetic Engineering Goals HIV Hematopoietic Hematopoietic Stem Cell Transplantation Hematopoietic stem cells Hemophilia A Hemorrhage Human Immune Tolerance Immune response Immunization Immunologic Deficiency Syndromes Immunosuppression In Vitro Individual Insertional Mutagenesis Intravenous infusion procedures Joints Lentivirus Vector Mesenchymal Stem Cells Methods Modeling Modification Morbidity - disease rate Mus Outcome Pathway interactions Patients Performance Phase I Clinical Trials Plasma Proteins Population Procedures Production Property Proteins Protocols documentation Reagent Recombinants Regimen Reporting Retroviral Vector Retroviridae SIV Safety Stem cell transplant Stem cells System Testing Therapeutic Toxic effect Transgenes Transgenic Organisms Translating Transplantation Transplantation Conditioning Treatment Efficacy Viral Genes Xenograft procedure arthropathies base clinically relevant clinically significant conditioning cost design expression vector gene therapy gene therapy clinical trial gene transfer vector genetically modified cells human F8 protein in vivo inhibitor/antagonist mouse model novel preclinical study promoter protein expression public health relevance simian human immunodeficiency virus stem stem cell biology success

A Mouse Affect Anabolism Antibodies Biology Biomedical Engineering Blood Blood Cells Blood Clot Blood Coagulation Factor Blood coagulation Bone Marrow Transplantation CD34 gene Cell Lineage Cells Clinical Clinical Trials Data Development Disease Drug Kinetics Engraftment Factor VIII Family suidae Gene Mutation Gene Transfer Genetic Genetic Engineering Goals HIV Hematopoietic Hematopoietic Stem Cell Transplantation Hematopoietic stem cells Hemophilia A Hemorrhage Human Immune Tolerance Immune response Immunization Immunologic Deficiency Syndromes Immunosuppression In Vitro Individual Insertional Mutagenesis Intravenous infusion procedures Joints Lentivirus Vector Mesenchymal Stem Cells Methods Modeling Modification Morbidity - disease rate Mus Outcome Pathway interactions Patients Performance Phase I Clinical Trials Plasma Proteins Population Procedures Production Property Proteins Protocols documentation Reagent Recombinants Regimen Reporting Retroviral Vector Retroviridae SIV Safety Stem cell transplant Stem cells System Testing Therapeutic Toxic effect Transgenes Transgenic Organisms Translating Transplantation Transplantation Conditioning Treatment Efficacy Viral Genes Xenograft procedure arthropathies base clinically relevant clinically significant conditioning cost design expression vector gene therapy gene therapy clinical trial gene transfer vector genetically modified cells human F8 protein in vivo inhibitor/antagonist mouse model novel preclinical study promoter protein expression public health relevance simian human immunodeficiency virus stem stem cell biology success

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项目摘要

DESCRIPTION (provided by applicant): Hemophilia A is a congenital bleeding disorder caused by genetic mutations affecting a plasma protein, termed factor VIII (fVIII), whose function is to facilitate blood clotting. State of the art treatment for hemophilia A consists of frequent intravenous infusions of fVIII containing products. The current limitations to treating hemophilia are 1) the cost of fVIII products, 3) the development of immune responses against fVIII that block treatment efficacy, 3) morbidity due to joint disease resulting from repeated bleeding into individual joints and 4) the limitation of treatment to 30% of the world population. Due to the limited amount of fVIII needed to provide clinical benefit to the patient, hemophilia A is an attractive disease target for gene therapy, and three phase 1 clinical trials have been conducted. The outcome of these trials has been disappointing due to the extremely low, non-therapeutic levels of fVIII produced in each of the gene therapy strategies. We recently showed that a modified porcine fVIII transgene, designated BDDpfVIII, facilitates very high-level protein expression, and we demonstrated proof-of-concept that this transgene functions extremely efficiently in a mouse model of hemophilia A following transplantation of genetically-modified hematopoietic stem cells (HSCs). Specifically, we have shown that the expression of BDDpfVIII is superior to other bioengineered human fVIII expression constructs and that genetic modification and transplantation of HSCs results in curative fVIII levels. Additionally, curative fVIII activity levels are achieved after transplantation of BDDpfVIII-transduced HSCs following low-toxicity pre-transplantation conditioning with targeted immunosuppression, even in the context of pre-existing anti-human fVIII inhibitors. Therefore, we have overcome the major hurdle of low-level expression using a transgene that encodes a protein that has been used successfully in patients with hemophilia A. In the current application, we propose to more fully characterize the use of the high-expression construct and further our understanding of the critical parameters involved with this novel gene therapy strategy and study the biology of non-physiological BDDpfVIII expression in hematopoietic (blood) cells. To advance our studies toward clinical significance, we propose to 1) test clinically relevant HSC transplant conditioning regimens that more closely resemble those used routinely in human bone marrow transplant protocols and 2) test recombinant lentiviral vectors that have been demonstrated to display a reduction of insertional mutagenesis compared to oncoretroviruses. Finally, the optimized lentiviral vector(s) encoding BDDpfVIII will be tested for the ability to genetically modify human HSCs.

描述（由申请人提供）：血友病A是由影响血浆蛋白的基因突变引起的先天性出血障碍，称为VIII因子VIII（FVIII），其功能是促进血液凝结。血友病A的最先进的治疗方法由FVIII含有产物的频繁静脉输注。治疗血友病的当前局限性是1）FVIII产品的成本，3）对FVIII的免疫反应的发展，该反应阻断治疗疗效的FVIII，3）由于反复出血而导致的关节疾病引起的发病率，以及4）治疗限制到世界人群的30％。由于为患者提供临床益处所需的FVIII量有限，因此血友病A是基因治疗的有吸引力的疾病靶标，并且已经进行了三项1期临床试验。这些试验的结果令人失望，这是由于每个基因治疗策略中产生的FVIII的极低，非治疗水平。我们最近表明，一种修饰的猪FVIII转基因，指定为BDDPFVIII，促进了非常高级的蛋白质表达，我们证明了这种转克在基因植入植物植入植物的血液友善型血型茎细胞（HSCSS）之后的小鼠模型A中极有效地发挥作用。具体而言，我们已经表明，BDDPFVIII的表达优于其他生物工程的人体FVIII表达构建体，HSC的遗传修饰和移植会导致固化的FVIII水平。另外，即使在预先存在的抗人类FVIII抑制剂的背景下，在低毒性预移植调节后，在低毒性预移植调节后，BDDDPFVIII-TRANSDDS抑制的HSC的治愈性FVIII活性水平也达到。因此，我们使用基因编码的蛋白质克服了低水平表达的主要障碍，该基因编码已成功用于血友病A的蛋白。在当前的应用中，我们建议更充分地使用高表达构建体的使用，并进一步表征我们对这种新颖基因治疗策略和研究非素质学的生物学（表征）的关键参数的理解。为了提高我们的研究临床意义，我们建议1）测试与临床相关的HSC移植条件治疗方案，这些治疗方案与人骨髓移植方案常规相似，并且2）测试重组重组杀虫病载体，这些植物病毒载体已被证明显示出与Oncoretruse相比的插入性突变作用的减少。最后，将测试编码BDDPFVIII的优化慢病毒载体（S），以测试具有遗传修饰人类HSC的能力。