格兰酶K激活了整个补体级联
Carlos A Donado1, Erin Theisen1,2, Fan Zhang3
1Division of Rheumatology, Inflammation, and Immunity, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
Nature
|February 6, 2025
概括
一种由淋巴细胞衍生的酶Granzyme K (GZMK) 激活补体级联,导致类风湿性关节炎等疾病的炎症. 缺乏GZMK的小鼠显示炎症性疾病减少,突出GZMK
科学领域:
- 免疫学
- 蛋白酶的功能
- 补充系统生物学
背景情况:
- 大酶是主要来自细胞毒性淋巴细胞的血清蛋白酶.
- 它们在细胞死亡中的作用已确立,但细胞外功能,包括炎症,正在出现.
- 格兰酶K (GZMK) 在类风湿性关节炎的T细胞中大量存在,但其功能尚不清楚.
研究的目的:
- 阐明Granzyme K (GZMK) 的功能.
- 调查GZMK在激活补充级联中的作用.
- 确定GZMK对炎症疾病的贡献.
主要方法:
- 生物化学测试以评估GZMK对补充蛋白C2和C4的分裂.
- 在体外对补体激活途径的分析.
- 使用Gzmk缺乏的小鼠进行体内研究以评估炎症性疾病的表型.
- 风湿性关节炎的免疫组织化学分析.
主要成果:
- GZMK直接分裂补充蛋白C4和C2,启动补充级联.
- 由GZMK介导的激活会产生所有补充效应分子,包括厌氧毒素和膜攻击复合物.
- 在类风湿性关节炎中,GZMK局部化在补体激活区域.
- 缺乏Gzmk的小鼠表现出明显减少的关节炎和皮肤炎,并减少了补体激活.
结论:
- GZMK是经典补充级联的新型激活剂.
- 淋巴细胞衍生的GZMK在慢性炎症疾病中驱动补充介导的炎症.
- 向GZMK可能为炎症疾病提供治疗策略.
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