使用F NMR和DNP超极化对连体细胞表面相互作用的表征19
Chang Qi1, Nirmalya Pradhan1, Christian Hilty1
1Chemistry Department, Texas A&M University, College Station, Texas 77843, United States.
Analytical chemistry
|December 26, 2025
概括
超极化19F NMR测量了对活细胞的联体结合. 连接体放松率随细胞密度的增加而增加,这表明蛋白质相互作用增强了结合,这表明在药物发现中,基于细胞的模型超过了简单的膜.
科学领域:
- 生物物理学的生物物理.
- 化学生物学 化学生物学
- 药物发现 药物发现 药物发现
背景情况:
- 小分子连接体与细胞膜的相互作用对于药物开发至关重要.
- 核自旋放松是研究这些相互作用的关键生物物理参数.
- 超极化19F NMR为放松测量提供了增强的灵敏度.
研究的目的:
- 通过使用超极化的19F NMR来研究对活细胞的联结结合.
- 描述细胞密度和细胞类型对连接体诱导放松的影响.
- 为了比较连接体与活细胞的相互作用与模型膜.
主要方法:
- 利用超极化的19F旋转来增强单扫描NMR中的信号.
- 测量了两种药物分子 (ICT5040和TFBC) 在不同细胞密度和类型的R2放松率.
- 活细胞 (DU4475,4T1,HEK293T) 的放松率与小单状囊泡的放松率进行比较.
主要成果:
- 连接体放松率与细胞密度线性增加,表明结合和.
- 超极化ICT5040在细胞中的放松性比在囊泡中的放松性更强,超出了脂质度正常化.
- 悬浮生长的DU4475细胞表现出比附着细胞更大的放松性,在素治疗后,放松性下降,这意味着蛋白质相互作用.
结论:
- 细胞相互作用,特别是与蛋白质的相互作用,显著影响着连接体结合和放松性.
- 模型膜可能无法完全复制体内结合环境.
- 超极化R2放松计是一种有前途的工具,用于研究生物物理和药物发现背景下的联体细胞相互作用.
相关概念视频
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