在人类造血干细胞中基和原始编辑的基因毒性影响
Martina Fiumara1,2, Samuele Ferrari3,4, Attya Omer-Javed1
1San Raffaele Telethon Institute for Gene Therapy, IRCCS San Raffaele Scientific Institute, Milan, Italy.
Nature biotechnology
|September 7, 2023
概括
基和主要编辑器 (BEs和PE) 对精确的基因工程具有前景,但可能导致有害的细胞反应和基因毒性. 在临床应用之前需要进一步的研究.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 生物技术是生物技术.
背景情况:
- 基编辑器 (BEs) 和主要编辑器 (PE) 通过避免DNA双链断裂,提供精确的基因组编辑,与基于核酶的方法不同.
- 有限的数据存在于细胞反应和基因毒性与BEs和PE在人类造血干细胞和祖细胞相关.
研究的目的:
- 为了比较最先进的BEs和PEs与人体造血干细胞和原始细胞中的Cas9的效率,细胞毒性和基因毒性.
- 调查这些编辑系统引起的转录组变化和目标/全基因组基因毒性影响.
主要方法:
- 在人类造血干细胞和原始细胞中对BEs,PE和Cas9进行比较分析.
- 编辑效率,细胞毒性,转录基因特征和DNA损伤 (双链断裂,删除,转位) 的评估.
- 评估基因毒性副产品和突变格局的变化.
主要成果:
- BEs和PE诱导了不良的转录反应,降低了编辑效率和造血重组.
- BEs和PE产生了DNA双链断裂和基因毒性副产品,其频率低于Cas9.
- 由于基础切除修复抑制不完全,cytidine BEs表现出最强的效应,部分通过优化mRNA传递减轻.
- 通过增加核酸变异,BEs显著改变了全基因组突变格局.
结论:
- 虽然BE和PE精确,但在造血干细胞和祖细胞中引起有害的细胞反应和基因毒性.
- 这些发现引发了关于BE和PE临床应用的安全问题,需要进一步研究.
- 优化的传递和表达策略可以减轻一些不良影响,但全基因组突变变异仍然是一个问题.
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