由NXT007介导的血静电位被激活蛋白C催化,激活因子V的无活化所抑制
Yuto Nakajima1,2, Kenichi Ogiwara1, Keito Inaba3
1Department of Pediatrics, Nara Medical University, Kashihara, Nara, Japan.
Research and practice in thrombosis and haemostasis
|December 20, 2023
概括
活性蛋白C (APC) 不会干扰NXT007在缺乏VIII因子的血中增强血液凝固的能力. 这种工程抗体即使在APC存在时也保持了静血功能,显示了它在治疗出血障碍方面的可靠性.
科学领域:
- 血液学 血液学 血液学
- 生物化学 生物化学
- 药理学 药理学是指药理学的学科.
背景情况:
- 活性蛋白C (APC) 是一种天然的抗凝剂,可以使凝血因子Va (FVa) 和VIIIa (FVIIIa) 失活.
- NXT007是一种工程双特异性抗体,旨在增强因子VIII缺乏血中的血静.
- 目前尚不清楚APC和NXT007的促凝活性之间的相互作用.
研究的目的:
- 调查APC对由NXT007.7.介导的血静功能的影响.
- 为了确定APC是否影响NXT007在缺乏VIII因子的血中恢复凝血的能力.
主要方法:
- 使用正常血和缺乏第八因子的血进行了血栓生成试验 (TGA),NXT007和APC的度各不相同.
- XA因子生成试验评估了APC对NXT007和FVIIIa辅因子活性的直接影响.
- 使用缺乏V因子的血和V因子的莱登血进行了实验,有或没有抗FVIII抗体,以评估APC在不同凝血因子环境中的NXT007的影响.
主要成果:
- 在含有NXT007的VIII因子缺乏血中,APC剂量依赖地抑制了血栓生成,类似于它在正常血中的作用.
- 通过NXT007介导的FXa生成没有受到APC的损害,这表明APC在TGA中的作用是由于FVa的失活.
- NXT007驱动的血栓生成仍然对APC介导的FVa无活化敏感,即使存在赋予APC耐药性的V因子突变.
结论:
- NXT007有效地提高了缺乏第八因子的血中的血静,而不会影响APC的抗凝功能.
- 在NXT007的存在下,FVa的APC介导下调是保留的,即使有抗APC的V因子突变.
- 关于与天然抗凝血剂通路的相互作用,NXT007显示出有利的安全概况.
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