在免疫球蛋白CL域中识别潜在的C1结合位点
Saeko Yanaka1,2,3, Atsuji Kodama1, Shigetaka Nishiguchi1
1Department of Creative Research, Exploratory Research Center on Life and Living Systems (ExCELLS), Department of Life and Coordination-Complex Molecular Science, Institute for Molecular Science (IMS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan.
International immunology
|April 2, 2024
概括
人类免疫球蛋白卡帕 (Cκ) 域与补充蛋白C1q结合,类似于小鼠对应物. 这种与抗原无关的相互作用可能会导致不受控制的补体激活,突出显示潜在的抗体工程目标.
科学领域:
- 免疫学 免疫学 免疫学
- 结构生物学 结构生物学
- 补充系统 补充系统
背景情况:
- 免疫球蛋白G (IgG) 在抗原结合时通过C1招募启动补充.
- 之前报告的一种缺乏Cγ1域的小鼠IgG突变通过单体C1q相互作用独立于抗原激活补充.
研究的目的:
- 研究补充蛋白C1q与人类CL异型 (Cκ和Cλ) 之间的相互作用.
- 确定结合位点和控制C1q与人类Cκ域相互作用的机制.
主要方法:
- 使用高速原子力显微镜 (HS-AFM) 进行单分子定量观测.
- 核磁共振 (NMR) 光谱学.核磁共振 (NMR) 光谱学.核磁共振 (NMR) 光谱学.核磁共振 (NMR) 光谱学.
- 突变的实验. 突变的实验.
主要成果:
- 人类Cκ域显示出显著的C1q结合能力,与小鼠Cκ域相比,优于Cλ类型.
- 对于C1q,已确定Cκ域 (以Glu194为中心) 上的一个保留的结合位点,Cλ域中缺席.
- 发现Cγ1域的高同电点阻碍了Cκ-C1q相互作用,这表明其去除有助于结合.
结论:
- 人类Cκ域可以独立于抗原结合C1q,可能导致不受控制的补充激活.
- Cγ1域影响了C1q结合动态.
- 已识别的Cκ-C1q相互作用点为治疗抗体工程提供了标,以控制补体激活.
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