通过人类的caspase-12多态体对内毒素反应的微分调节
Maya Saleh1, John P Vaillancourt, Rona K Graham
1Department of Biochemistry, Molecular Biology and Pharmacology, Merck Frosst Centre for Therapeutic Research, Montreal, Quebec H9H 3L1, Canada.
Nature
|May 7, 2004
概括
人类caspase-12 (Csp12-L) 的遗传变异减少了对内毒素的炎症反应. 这种在非洲血统的人群中发现的变异可能会增加患严重败血症的风险.
科学领域:
- 分子生物学分子生物学
- 免疫学 免疫学 免疫学
- 遗传学 是一个遗传学.
背景情况:
- 卡斯帕酶是炎症和亡中的关键蛋白酶.
- 人类的卡斯帕斯被分为细胞因子成熟和亡子家族.
- 卡斯帕-12,虽然与细胞因子卡斯帕相关,但已与小鼠的ER压力诱导的亡有关.
研究的目的:
- 研究人类caspase-12中单核酸多态的功能后果.
- 为了确定这种多态性对炎症和亡途径的影响.
- 为了探索caspase-12变体在败血症发病过程中的潜在作用.
主要方法:
- 在人体caspase-12中分析单核酸多态性.
- 在活体全血中对脂聚糖 (LPS) 刺激的反应中评估细胞因子的产生.
- 评估细胞亡敏感性.
- 在严重败血症患者中对Csp12-L等位体进行初步频率分析.
主要成果:
- 在caspase-12中,一种特定的单核酸多态性导致两种蛋白质形式:截断 (Csp12-S) 和全长 (Csp12-L).
- 在非洲裔人群中普遍存在的Csp12-L变体减少了脂多糖刺激的细胞因子生产.
- Csp12-L并没有显著影响亡敏感性.
- 在患有严重败血症的非裔美国人中,Csp12-L等位基频率更高.
结论:
- 这种Csp12-L变异减弱了对内毒素的炎症和先天免疫反应.
- 卡斯巴-12多态可能是发展严重败血症的危险因素.
- 这一发现突显了基因变异在免疫反应和疾病易感性中的作用.
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