Emerging evidence has documented that multisystem organ failure in coronavirus disease 2019 (COVID-19) patients is strongly associated with various coagulopathies. Treatments for COVID-19-associated coagulopathy are still a clinical challenge. An advancement in the knowledge of mechanisms of the excessive or inappropriate activation of the complement cascade involved in the genesis of COVID-19-associated coagulopathy might be a fundamental approach for developing novel classes of anticoagulant drugs. In this context, there is emerging evidence indicating that C5a, a component of the complement system, and its receptors (C5aRs) play a critical role in the genesis of the COVID-19-associated hypercoagulable state. Thus, this review describes the mechanisms by which C5a/C5aR signaling participates in the cascade of events involved in the pathophysiology of COVID-19-associated coagulopathy. Furthermore, it highlights the current possibilities for the development of a novel therapeutic approach for COVID-19 patients that targets C5a/C5aRs signaling.

新出现的证据表明，2019 年冠状病毒病 (COVID-19) 患者的多系统器官衰竭与各种凝血病密切相关。COVID-19 相关凝血病的治疗仍然是一个临床挑战。对参与 COVID-19 相关凝血病发生的补体级联过度或不适当激活机制的认识的进步可能是开发新型抗凝药物的基本方法。在这种情况下，有新证据表明补体系统的一个组成部分 C5a 及其受体 (C5aRs) 在 COVID-19 相关高凝状态的发生中起着关键作用。因此，本综述描述了 C5a/C5aR 信号通路参与 COVID-19 相关凝血病病理生理学级联事件的机制。此外，它强调了目前为 COVID-19 患者开发一种靶向 C5a/C5aRs 信号的新型治疗方法的可能性。