Gene Therapy for SCID-X1 with Low Dose Busulfan and a SIN-lentiviral Vector

使用低剂量白消安和 SIN 慢病毒载体对 SCID-X1 进行基因治疗

基本信息

批准号：
10827632
负责人：
DAVID A WILLIAMS
金额：
$ 128.56万
依托单位：
BOSTON CHILDREN'S HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-07-07 至 2024-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10827632
关键词：
Gene Therapy SCID X1 Low

项目摘要

Gene therapy using autologous C034+ cells is a promising treatment for primary immunodeficiency, particularly for individuals without optimal allogeneic donors. SCIO-X1 is caused by mutations in IL2RG, which encodes the common gamma chain (ye) of multiple cytokine receptors. Boys with SCIO-X1 lack T and NK cells, and their B cells fail to produce antibodies due to the lack of IL-7, IL-15 and IL-21 function respectively. This project seeks to test the efficacy and safety of a new self-inactivating lentiviral (LV) vector to treat SCIO- X1. We hypothesize that this trial will improve immune reconstitution through the introduction of low dose busulfan conditioning (Aim 1) and improve safety through the change from a gammaretroviral (yRV) vector used in previous trials to the LV vector in this trial (Aim 2). Previous trials of gene therapy for SCIO-X1 have infused cells without chemotherapy conditioning, which resulted in robust T cell recovery and gene marking, but negligible gene marking in B cells and failure of humoral immune reconstitution. Initial development and marking in NK cells was not sustained. In Aim 1 we will examine the impact of low dose busulfan conditioning on 1) cell type specific engraftment and gene marking, 2) in vivo T cell reconstitution, T cell phenotype and TRB repertoire by deep sequencing, 3) in vivo humoral immune reconstitution, B cell number, phenotype, IL-21 dependent function and IGH repertoire by deep sequencing, 4) NK cell number, phenotype and function. Previous trials of gene therapy for SCIO-X1 have used a yRV vector with intact viral promoters/enhancers, which resulted in 5/20 patients developing T cell leukemia due to insertional oncogenesis. Gene therapy using a self-inactivating yRV vector in which viral enhancers have been deleted shows encouraging evidence of reduced insertion sites near lymphoid oncogenes, but an initial insertion site pattern that is still risky. The proposed trial in this application will further improve safety by using a self-inactivating LV vector. In Aim 2 we will investigate the initial insertion site pattern in the patients' C034+ transduced cells and compare samples from the proposed trial to historical trials using yRV, analyze insertion site profile in peripheral blood after gene therapy to perform lineage tracing and compare clustering with samples from previous trials.

使用自体 C034+ 细胞的基因治疗是治疗原发性免疫缺陷的一种有前途的治疗方法，特别是对于没有最佳同种异体供体的个体。 SCIO-X1 是由 IL2RG 突变引起的，它编码多种细胞因子受体的共同伽马链（ye）。患有 SCIO-X1 的男孩缺乏 T 和NK细胞，其B细胞由于缺乏IL-7、IL-15和IL-21功能而不能产生抗体分别。该项目旨在测试新型自失活慢病毒（LV）的功效和安全性用于治疗 SCIO-X1 的载体。我们假设这项试验将通过以下方式改善免疫重建：引入低剂量白消安调理（目标 1），并通过从先前试验中使用的伽马逆转录病毒 (yRV) 载体与本次试验中使用的 LV 载体相同（目标 2）。之前 SCIO-X1 基因治疗的试验是在没有化疗的情况下输注细胞，这导致了 T 细胞的强劲恢复和基因标记，但 B 细胞中的基因标记可以忽略不计并且失败体液免疫重建。 NK 细胞的最初发育和标记并未持续。目标 1 我们将研究低剂量白消安调节对 1) 细胞类型特异性植入的影响和基因标记， 2) 通过深度测序进行体内 T 细胞重建、T 细胞表型和 TRB 库，3) 体内体液免疫重建、B 细胞数量、表型、IL-21 依赖性功能和 IGH 库通过深度测序，4）NK细胞数量、表型和功能。之前的 SCIO-X1 基因治疗试验使用了具有完整病毒的 yRV 载体启动子/增强子，导致 5/20 的患者由于插入而发展为 T 细胞白血病肿瘤发生。使用自失活 yRV 载体进行基因治疗，其中病毒增强子已被删除显示了淋巴癌基因附近插入位点减少的令人鼓舞的证据，但最初插入位点模式仍然存在风险。本申请中拟议的试验将通过以下方式进一步提高安全性：使用自失活 LV 载体。在目标 2 中，我们将研究初始插入位点模式患者的 C034+ 转导细胞，并将拟议试验的样本与历史试验进行比较，使用 yRV，分析基因治疗后外周血中的插入位点概况以进行谱系追踪和将聚类与之前试验的样本进行比较。