一种具有降低细胞毒性和通过巨基突变增强蛋白质表达的新型自我放大mRNA
Yue Gong1, Danni Yong1, Gensheng Liu1
1Shanghai Virogin Biotech Co. Ltd, Jiading District, Shanghai, 200000, China.
Advanced science (Weinheim, Baden-Wurttemberg, Germany)
|September 24, 2024
概括
自放大mRNA (saRNA) 非结构蛋白的突变减少了复制和先天免疫反应. 这增强了有效载荷表达并降低了细胞毒性,优化了saRNA用于治疗应用.
科学领域:
- 分子生物学分子生物学
- 免疫学 免疫学 免疫学
- 疫苗技术技术 疫苗技术
背景情况:
- 自放大mRNA (saRNA) 提供剂量节约优势比传统的非复制mRNA (nrmRNA) 由于其自我复制机制.
- 优化saRNA表达效率对于其在疫苗和治疗中更广泛的应用至关重要.
- saRNA的复制可以通过双链RNA (dsRNA) 传感器触发先天性免疫反应,从而可能限制其有效性并引起细胞毒性.
研究的目的:
- 研究saRNA的非结构蛋白 (NSP) 突变对其复制,免疫性和有效载荷表达的影响.
- 确定减少saRNA诱导的先天性免疫反应和提高蛋白质翻译效率的策略.
主要方法:
- 在干扰素压力下对saRNA进行体外适应传递,以选择突变.
- 鉴定NSP3宏观基因 (MD) 中突变对酶活性和saRNA特性的影响的特征.
- 转录组测序以分析dsRNA传感器和免疫反应的激活.
- 在体外和体内评估蛋白质表达,翻译抑制和细胞亡.
主要成果:
- 两个稳定突变 (Q48P和I113F) 在NSP3宏基因中减弱了其MAR水解活性.
- 与野生型saRNA (wt saRNA) 相比,突变的saRNA表现出复制减少,但有效载荷表达显著增加.
- 突变的saRNA显示dsRNA传感器的激活减少,导致先天免疫反应减少.
- 与突变的saRNA一起观察到较少的翻译抑制和亡,从而使蛋白质表达在体外和体内都更高.
结论:
- 针对NSP3的saRNA的遗传修饰可以减少依赖复制的dsRNA诱导的先天免疫反应.
- 这些修改提高了有效载荷转换效率,并减轻了saRNA诱导的细胞毒性.
- 这一战略代表了优化saRNA技术以改善治疗和疫苗应用的有希望的方法.
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