Hart Kevyn L, Liu Boya, Brown Devin, Campo-Fernandez Beatriz, Tam Kevin, Orr Katherine, Hollis Roger P, Brendel Christian, Williams David A, Kohn Donald B
Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA 02115, USA.
Mol Ther Methods Clin Dev. 2024 Apr 24;32(2):101254. doi: 10.1016/j.omtm.2024.101254. eCollection 2024 Jun 13.
A major limitation of gene therapy for sickle cell disease (SCD) is the availability and access to a potentially curative one-time treatment, due to high treatment costs. We have developed a high-titer bifunctional lentiviral vector (LVV) in a vector backbone that has reduced size, high vector yields, and efficient gene transfer to human CD34 hematopoietic stem and progenitor cells (HSPCs). This LVV contains locus control region cores expressing an anti-sickling β-globin gene and two microRNA-adapted short hairpin RNA simultaneously targeting and transcripts to maximally induce fetal hemoglobin (HbF) expression. This LVV induces high levels of anti-sickling hemoglobins (HbA + HbF), while concurrently decreasing sickle hemoglobin (HbS). The decrease in HbS and increased anti-sickling hemoglobin impedes deoxygenated HbS polymerization and red blood cell sickling at low vector copy per cell in transduced SCD patient CD34 cells differentiated into erythrocytes. The dual alterations in red cell hemoglobins ameliorated the SCD phenotype in the SCD Berkeley mouse model . With high titer and enhanced transduction of HSPC at a low multiplicity of infection, this LVV will increase the number of patient doses of vector from production lots to decrease costs and help improve accessibility to gene therapy for SCD.
由于治疗成本高昂，镰状细胞病（SCD）基因治疗的一个主要限制是难以获得且难以负担这种可能具有治愈性的一次性治疗。我们开发了一种高滴度双功能慢病毒载体（LVV），其载体骨架尺寸减小、载体产量高，并且能有效地将基因转移到人类CD34造血干细胞和祖细胞（HSPCs）中。这种LVV包含表达抗镰状β-珠蛋白基因的基因座控制区核心，以及两个同时靶向和转录本的微小RNA适配短发夹RNA，以最大程度地诱导胎儿血红蛋白（HbF）表达。这种LVV可诱导高水平的抗镰状血红蛋白（HbA + HbF），同时降低镰状血红蛋白（HbS）。在转导的SCD患者分化为红细胞的CD34细胞中，低细胞载体拷贝数时，HbS的降低和抗镰状血红蛋白的增加可阻碍脱氧HbS聚合和红细胞镰状化。红细胞血红蛋白的双重改变改善了SCD伯克利小鼠模型中的SCD表型。这种LVV在低感染复数时具有高滴度并增强了对HSPC的转导，将增加生产批次中载体的患者剂量数量，从而降低成本，并有助于提高SCD基因治疗的可及性。
