Abstract:
Base editing of hematopoietic stem/progenitor cells (HSPCs) is an attractive strategy for treating immunohematologic diseases. However, the feasibility of using adenine-base-edited HSPCs for treating X-linked severe combined immunodeficiency (SCID-X1), the influence of dose-response relationships on immune cell generation, and the potential risks have not been demonstrated in vivo. Here, a humanized SCID-X1 mouse model was established, and 86.67% ± 2.52% (n = 3) of mouse hematopoietic stem cell (HSC) pathogenic mutations were corrected, with no single-guide-RNA (sgRNA)-dependent off-target effects detected. Analysis of peripheral blood over 16 weeks post-transplantation in mice with different immunodeficiency backgrounds revealed efficient immune cell generation following transplantation of different amounts of modified HSCs. Therefore, a large-scale infusion of gene-corrected HSCs within a safe range can achieve rapid, stable, and durable immune cell regeneration. Tissue-section staining further demonstrated the restoration of immune organ tissue structures, with no tumor formation in multiple organs. Collectively, these data suggest that base-edited HSCs are a potential therapeutic approach for SCID-X1 and that a threshold infusion dose of gene-corrected cells is required for immune cell regeneration. This study lays a theoretical foundation for the clinical application of base-edited HSCs in treating SCID-X1.
摘要:
造血干/祖细胞(HSPC)的碱基编辑是治疗免疫血液病的有吸引力的策略。然而,使用腺嘌呤碱基编辑的HSPC治疗X连锁严重联合免疫缺陷(SCID-X1)的可行性,剂量反应关系对免疫细胞生成的影响,潜在风险尚未在体内得到证实。这里,建立了人源化SCID-X1小鼠模型,86.67%±2.52%(n=3)的小鼠造血干细胞(HSC)致病突变得到纠正,没有检测到单向导RNA(sgRNA)依赖性脱靶效应。对具有不同免疫缺陷背景的小鼠移植后16周的外周血的分析揭示了在移植不同量的修饰的HSC后有效的免疫细胞生成。因此,在安全范围内大规模输注基因校正的HSC可以实现快速,稳定,和持久的免疫细胞再生。组织切片染色进一步证明了免疫器官组织结构的恢复,在多个器官中没有肿瘤形成。总的来说,这些数据表明,碱基编辑的HSC是SCID-X1的潜在治疗方法,免疫细胞再生需要阈值输注剂量的基因校正细胞.本研究为碱基编辑的HSCs治疗SCID-X1的临床应用奠定了理论基础。