Gene Therapy in Hematopoietic Cells

造血细胞基因治疗

• 批准号: 7304848
• 负责人: HANS-PETER KIEM
• 金额: $ 56.17万
• 依托单位: FRED HUTCHINSON CANCER RESEARCH CENTER
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-15 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7304848
• 关键词: CD34 molecule; Lentivirus; biotechnology; blood cell count; busulfan; disease /disorder model; dogs; flow cytometry; gammaretrovirus; gene therapy; hematopoietic stem cells; hematopoietic tissue transplantation; longitudinal animal study; method development; nonhuman therapy evaluation; nucleic acid repetitive sequence; pharmacokinetics; polymerase chain reaction; pyruvate kinase deficiency; stem cell transplantation; transfection /expression vector; virus integration

The overall objective of this project is to develop strategies, which will allow the efficient and safe treatment of hematopoietic diseases by hematopoietic stem cell (HSC) gene therapy. Unfortunately neither in vitro studies nor studies in the mouse model have been predictive for safety and efficacy of gene transfer in large animals or humans, thus we will use the dog model which will also allow us to evaluate improved strategies directly in a disease model. While gene transfer efficiencies into HSCs in the dog model and other large animals have improved significantly over the past several years, the development of leukemia in 3 patients in the French X-linked severe combined immunodeficiency (XSCID) gene therapy trial has shifted the emphasis from efficacy to safety. Thus, we will use the dog model to study the safety of 3 commonly used integrating vector systems: gammaretrovirus, lentivirus, and foamy virus vectors. Using these vector systems, we have been able to achieve efficient transduction of canine long-term repopulating cells with stable gene transfer levels >5% in a significant number of dogs. Thus, we now have a unique resource available to study in Specific Aim 1 the safety of HSC gene transfer with these vectors. In Specific Aim 2, we will further optimize transduction conditions for foamy and lentiviral vectors to minimize risks from insertional mutagenesis. We will focus on lentivirus and foamy virus vectors since, in contrast to gammaretroviral vectors, these vector systems allow for efficient transduction using short transduction cultures. This is particularly important for stem cell gene therapy in a nonmyeloablative transplant setting where maintenance of stem cells is crucial for the ability to compete with surviving endogenous stem cells. Thus, in Specific Aim 3 we will use these vector systems in a nonmyeloablative setting and also explore whether in vivo selection strategies can improve gene transfer levels after nonmyeloablative conditioning. Finally, in Specific Aim 4 we will test improved gene transfer protocols in a canine genetic disease model. The availability of a clinically relevant large animal model should allow us to quickly translate our findings to clinical HSC gene therapy studies.

该项目的总体目标是制定战略，这将使高效和安全