通过准其表皮生长因子类1域中的2个独特补丁,可以通过纳米体防止XII因子接触激活
Rowan Frunt1, Hinde El Otmani1, Simone Smits1
1Central Diagnostic Laboratory Research, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.
Journal of thrombosis and haemostasis : JTH
|June 19, 2024
概括
研究人员在因子XII的EGF-1域中发现了两个带电补丁,这对表面结合和接触激活至关重要. 用抗体向这些贴片可以预防血栓形成,特别是由医疗设备引起的血栓形成.
科学领域:
- 生物化学 生物化学
- 血液学 血液学 血液学
- 免疫学 免疫学 免疫学
背景情况:
- 因素XII (FXII) 通过表面结合启动接触激活,主要是通过其表皮生长因子-1 (EGF-1) 域.
- 抑制FXII表面结合是预防医疗器械相关血栓的潜在治疗策略.
研究的目的:
- 用重链单抗体 (VHH) 的可变域阐明和阻止EGF-1介导的FXII表面结合.
主要方法:
- 在EGF-1域内两个带正电荷的补丁中创建了具有谷氨酸替代物的FXII变体.
- 评估了FXII变体在接触激活中的作用,使用考林拉下,氨基溶解活性和凝固试验.
- 开发了FXII EGF-1域特定的VHHs来抑制表面结合和接触激活.
主要成果:
- 在FXII EGF-1域中确定了两个关键的正电荷补丁 (上游:73K74K76K78H81K82H;下游:87K113K).
- 中和这些贴片减少了99%的FXII高结合和94%的自动激活,显著延长了凝血时间.
- 开发了三种VHHs,其中"F2"有效地抑制了FXII表面结合和血中的接触激活,而不影响FXII静止.
结论:
- 在FXII EGF-1中,两个独特的正电荷贴片协同介导表面结合,对于接触激活至关重要.
- 将FXII EGF-1 特定的VHHs 向这些贴片可选择性地抑制表面结合和接触激活,同时保持细胞因子静止.
- 这些已识别的补丁代表了预防医疗器械诱导血栓的潜在可用药物标.
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