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Bacterial Delivery of RNAi Effectors: Transkingdom RNAi
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通过siRNA通过TLR3抑制序列和目标独立的血管生成
Mark E Kleinman1, Kiyoshi Yamada, Atsunobu Takeda
1Department of Ophthalmology, University of Kentucky, Lexington, Kentucky 40506, USA.
Nature
|March 28, 2008
概括
小干扰RNA (siRNA) 通过通用类受体3 (TLR3) 抑制胆道新血管化 (CNV),而不是基因沉默. 这一发现表明,通用siRNAs可以通过激活TLR3,独立于针对特定基因来治疗血管性疾病.
科学领域:
- 分子生物学分子生物学
- 免疫学 免疫学 免疫学
- 眼科医生 眼科 眼科
背景情况:
- 目前临床试验用于盲导胆道新血管化 (CNV) 使用小干扰RNA (siRNA) 向血管内皮生长因子-A (VEGFA) 或其受体VEGFR1,依赖细胞内RNA干扰 (RNAi).
- 在这些试验中,siRNA的有效性被认为是由于VEGFA或VEGFR1.1的特定基因沉默.
研究的目的:
- 研究siRNA抑制CNV的机制.
- 要确定siRNA对CNV的影响是否取决于针对Vegfa或Vegfr1.1,等特定基因.
- 探索新血管化的siRNA介导抑制的替代途径.
主要方法:
- 将各种siRNAs (针对非哺乳动物基因,非表达基因,非基因组序列,RNAi无能序列) 给 CNV.
- 评估了CNV抑制,并将其与向Vegfa或Vegfr1的siRNA进行了比较.
- 研究了细胞表面类似受体3 (TLR3),其适配器TRIF,以及诱导细胞因子 (干扰素-马,干扰素-12) 在siRNA介导的CNV抑制中的作用.
- 评估siRNA对皮肤新血管化的影响.
- 确定了新血管化抑制所需的最小siRNA长度.
- 研究了人体内皮细胞中表面TLR3的表达以及TLR3变体 (412FF) 对siRNA诱导的细胞毒性的影响.
主要成果:
- 通过siRNA介导的CNV抑制观察到各种非特异性和RNAi无能力的siRNAs,与Vegfa/Vegfr1向siRNAs相比.
- 通过细胞表面TLR3,TRIF和干扰素-和介质蛋白-12,独立于非位RNAi或干扰素-α/β激活的诱导来调节CNV抑制.
- 由siRNA诱导的新血管化的抑制需要至少21个核酸的长度,这表明与TLR3.3的直接相互作用.
- 非向的siRNA有效抑制了皮肤新血管化.
- 人体内皮细胞表达表面TLR3,一个特定的TLR3变体 (412FF) 赋予了对siRNA诱导的细胞毒性的折射性.
结论:
- 通过siRNA抑制CNV是一种由细胞表面TLR3激活介导的类效应,而不是针对特定基因的细胞内RNA干扰.
- 通用siRNAs通过激活TLR3可能为血管性疾病提供治疗策略.
- 这些发现表明基于TLR3变体的个性化药物遗传疗法的潜力,并突出了siRNA治疗可能带来意想不到的血管或免疫效应的可能性.
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