一个类似Toll的受体识别了细菌DNA.
1Department of Host Defense, Research Institute for Microbial Diseases, Osaka University and Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Suita.
Nature
|December 29, 2000
概括
含有CpG基因的细菌DNA可以激活免疫细胞. 研究人员发现,Toll-like受体9 (TLR9) 调解了这种反应,突出了它在区分外来与自身DNA中的作用.
科学领域:
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 富含非甲基化CpG二核酸的细菌DNA可以刺激哺乳动物的免疫细胞.
- 哺乳动物的DNA具有较低的CpG频率和甲基化,缺乏免疫刺激活性.
- CpG DNA引发了T-辅助-1 (Th1) 反应,显示了作为疫苗辅助剂的治疗潜力.
研究的目的:
- 阐明CpG DNA介导的免疫细胞激活背后的分子机制.
- 为了确定负责识别CpGDNA的特定受体.
主要方法:
- 使用了托尔类受体9缺乏 (TLR9-/-) 的小鼠.
- 评估免疫细胞反应,包括细胞增殖,细胞因子产生和树突细胞成熟.
- 在体内对CpG DNA挑战的评估反应.
主要成果:
- TLR9-/-小鼠对CpGDNA没有反应,包括缺少胞增殖,炎症性细胞因子产生和树突细胞成熟.
- TLR9-/-小鼠对致命的CpG DNA效应具有抗性,并且没有显示过高的促炎细胞因子.
- 活体中由cpG-DNA诱导的Th1反应在TLR9-/-小鼠中被取消.
结论:
- 细胞对CpG DNA的反应受到托尔类受体9 (TLR9) 的关键介导.
- 在脊椎动物中,TLR9作为传感器来区分细菌DNA与自身DNA.
- 这一发现澄清了CpG DNA免疫激活的机制及其对疫苗开发的影响.
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