In vivo selection of genetically modified erythroblastic progenitors leads to long-term correction of β-thalassemia
In vivo selection of genetically modified erythroblastic progenitors leads to long-term correction of β-thalassemia
复制标题
DOI：
10.1073/pnas.0711666105
复制
发表时间：
2008-07-29
影响因子：
11.1
通讯作者：
Ferrari, Giuliana
中科院分区：
文献类型：
--
作者：
Miccio, Annarita;Cesari, Rossano;Ferrari, Giuliana
β 地中海贫血的基因治疗需要将 β 珠蛋白基因稳定转移到造血干细胞 (HSC) 中，并在成红细胞后代中实现高且受调节的血红蛋白表达。我们开发了一种红细胞特异性慢病毒载体，从含有来自β-珠蛋白基因座控制区的两个超敏位点的最小启动子/增强子元件驱动人类β-珠蛋白基因的表达。将转导的 HSC 移植到地中海贫血小鼠中，可以稳定且长期地纠正贫血，所有红细胞都表达转基因。转导 HSC 的频率为 30-50%，每个细胞的平均载体拷贝数为 1，足以完全纠正地中海贫血表型。在库利贫血小鼠模型中，转导细胞移植可挽救死亡，导致正常或中间型地中海贫血表型。我们表明，基因校正的成红细胞经历体内选择，在基因组位点中携带原病毒整合的祖细胞优先存活，更有利于高水平的载体衍生表达。这些数据为基于部分清髓性移植方案的β-地中海贫血基因治疗方法提供了理论依据。
Gene therapy for beta-thalassemia requires stable transfer of a beta-globin gene into hematopoietic stem cells (HSCs) and high and regulated hemoglobin expression in the erythroblastic progeny. We developed an erythroid-specific lentiviral vector driving the expression of the human beta-globin gene from a minimal promoter/enhancer element containing two hypersensitive sites from the beta-globin locus control region. Transplantation of transduced HSCs into thalassemic mice leads to stable and long-term correction of anemia with all red blood cells expressing the transgene. A frequency of 30-50% of transduced HSCs, harboring an average vector copy number per cell of 1, was sufficient to fully correct the thalassemic phenotype. In the mouse model of Cooley's anemia transplantation of transduced cells rescues lethality, leading to either a normal or a thalassemia intermedia phenotype. We show that genetically corrected erythroblasts undergo in vivo selection with preferential survival of progenitors harboring proviral integrations in genome sites more favorable to high levels of vector-derived expression. These data provide a rationale for a gene therapy approach to beta-thalassemia based on partially myeloablative transplantation protocols.