Targeted in vivo gene transfer to hematopoietic stem cells

体内靶向基因转移至造血干细胞

• 批准号: 7469636
• 负责人: Nikunj V Somia
• 金额: $ 18.88万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-06-01 至 2010-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7469636
• 关键词: Acquired Immunodeficiency Syndrome; Applications Grants; Binding; Biological Assay; Biological Markers; Blood; Blood Cells; Bone Marrow; CD11 Antigens; CD3 Antigens; CD34 gene; Cell Culture System; Cell Lineage; Cell Surface Receptors; Cell surface; Cells; Chimera organism; Dendritic Cells; Disease; Engineering; Evaluation; Fanconi' s Anemia; Fc Receptor; Flow Cytometry; Gene Transfer; General Population; Genes; Hematological Disease; Hematopoietic; Hematopoietic Stem Cell Mobilization; Hematopoietic System; Hematopoietic stem cells; Hemoglobinopathies; Human; Human Placental Lactogen; Immunologic Deficiency Syndromes; In Vitro; Infection; Infusion procedures; Injection of therapeutic agent; Lentivirus Vector; Ligands; Lymphoid Cell; Marrow; Measures; Membrane Fusion; Modeling; Mus; Myelogenous; Numbers; PTPRC gene; Partner in relationship; Patients; Phenotype; Phosphotransferases; Population; Protein Binding Domain; Proto-Oncogene Protein c-kit; Public Health; Purpose; Recombinants; Retroviral Vector; Route; Sindbis Virus; Specificity; Stem Cell Factor; Stem cells; Surface; Testing; Therapeutic; Time; Tissues; Transgenic Organisms; Transplant Recipients; Transplantation; Viral Load result; Viral Vector; base; cell type; congenic; env Gene Products; gene therapy; gene transfer vector; human stem cells; in vivo; mutant; peripheral blood; receptor; research study; targeted delivery; therapeutic gene; vector; viral vector development; virus envelope

DESCRIPTION (provided by applicant): Efficient gene transfer to human hematopoietic stem cells (HSC) has the potential to correct a number of human hematologic and non-hematologic diseases. At present, gene transfer into HSC's is typically achieved ex vivo, involving isolation of stem cells, transferring a corrective gene into the cells and re-infusion of cells into the patient. For the purpose of achieving therapeutic gene transfer, there would be great utility in a vector that could achieve targeted gene transfer in vivo to HSC. For this R21 proposal we aim to develop and test in vivo lentiviral based gene transfer vectors that will target infection through molecules that are expressed on the surface of hematopoietic stem cells. We will (i) develop lentivirus vectors for targeting infection of HSC. This will be achieved by fusing protein domains that bind cell surface receptors expressed on HCS (including CD34, and the kinase receptors c-kit and Flt3) onto a mutant Sindbis virus envelope that is severely impaired for binding its receptor but is competent for membrane fusion. These vectors will be extensively characterized using in vitro cell culture systems. We will then proceed to (ii) evaluate vectors generated for targeting infection of hematopoietic stem cells in vivo. We will investigate two routes of delivery for targeting lentiviral vectors to HSC: (a) injection into the bone marrow and (b) systemic delivery after mobilization of HSC out of the marrow into blood. These experiments will critically test the feasibility of targeting infection to HSC in vivo. Targeting vector to cells in vivo has the potential advantage of increasing gene transfer to cells while decreasing viral load. It also avoids gene transfer to cells that could impede gene therapy i.e. dendritic cells. The targeting of hematopoietic stem cells will provide proof of principle for in vivo targeting and support its use as a therapeutic approach for key hematologic disorders, such as immunodeficiencies, AIDS and Fanconi anemia. Furthermore, results from these studies will have significant implications for targeted therapeutic gene transfer using retroviral vectors in general. Public Health Relevance: This grant proposal aims to develop and test viral vectors that are engineered to infect a specific cell type in the body. Here we propose to develop these to target infection of stem cells that are responsible for making all the cells of the blood. The development of these viral vectors will enable treatment of blood disorders by direct injection of these vectors into the body. The discoveries we make can also be applied to other diseases.

描述（由申请人提供）：高效基因转移到人造血干细胞（HSC）具有纠正许多人类血液和非血液疾病的潜力。目前，基因转移到HSC通常是体外实现的，包括分离干细胞，将纠正基因转移到细胞中，再将细胞输注到患者体内。为了实现治疗性基因转移，在体内实现靶向基因转移到HSC的载体将有很大的用处。对于这个R21提案，我们的目标是开发和测试体内基于慢病毒的基因转移载体，该载体将通过在造血干细胞表面表达的分子靶向感染。我们将(i)开发针对HSC感染的慢病毒载体。这将通过将结合HCS上表达的细胞表面受体（包括CD34、激酶受体c-kit和Flt3）的蛋白质结构域融合到突变的Sindbis病毒包膜上来实现，该病毒包膜因其受体的结合而严重受损，但能够进行膜融合。这些载体将广泛表征使用体外细胞培养系统。然后，我们将继续（ii）评估用于靶向体内造血干细胞感染的载体。我们将研究慢病毒载体靶向HSC的两种递送途径：(a)注射到骨髓中；(b)动员HSC从骨髓进入血液后全身递送。这些实验将严格检验体内HSC靶向感染的可行性。体内靶向载体具有增加基因向细胞转移的同时降低病毒载量的潜在优势。它还避免了基因转移到可能阻碍基因治疗的细胞，即树突状细胞。靶向造血干细胞将为体内靶向提供原理证明，并支持其作为关键血液系统疾病（如免疫缺陷、艾滋病和范可尼贫血）的治疗方法。此外，这些研究的结果将对利用逆转录病毒载体进行靶向治疗性基因转移具有重要意义。