Hemostasis and Platelet Research Laboratory, Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), CH-1010 Lausanne, Switzerland.
Int J Mol Sci. 2022 Feb 25;23(5):2536. doi: 10.3390/ijms23052536.
Procoagulant platelets are a subtype of activated platelets that sustains thrombin generation in order to consolidate the clot and stop bleeding. This aspect of platelet activation is gaining more and more recognition and interest. In fact, next to aggregating platelets, procoagulant platelets are key regulators of thrombus formation. Imbalance of both subpopulations can lead to undesired thrombotic or bleeding events. COAT platelets derive from a common pro-aggregatory phenotype in cells capable of accumulating enough cytosolic calcium to trigger specific pathways that mediate the loss of their aggregating properties and the development of new adhesive and procoagulant characteristics. Complex cascades of signaling events are involved and this may explain why an inter-individual variability exists in procoagulant potential. Nowadays, we know the key agonists and mediators underlying the generation of a procoagulant platelet response. However, we still lack insight into the actual mechanisms controlling this dichotomous pattern (i.e., procoagulant versus aggregating phenotype). In this review, we describe the phenotypic characteristics of procoagulant COAT platelets, we detail the current knowledge on the mechanisms of the procoagulant response, and discuss possible drivers of this dichotomous diversification, in particular addressing the impact of the platelet environment during in vivo thrombus formation.
促凝血小板是激活血小板的一种亚型，可维持凝血酶的生成，以巩固血栓并停止出血。血小板激活的这一方面越来越受到重视。事实上，除了聚集血小板外，促凝血小板还是血栓形成的关键调节剂。这两种亚群的失衡可导致不期望的血栓形成或出血事件。COAT 血小板源自于能够积累足够的细胞质钙以触发介导其聚集特性丧失和新的黏附和促凝特性发展的特定途径的具有共同促聚集表型的细胞。涉及复杂的信号级联事件，这可能解释了为什么促凝潜能存在个体间的差异。如今，我们了解了产生促凝血小板反应的关键激动剂和介质。然而，我们仍然缺乏对控制这种二分模式（即促凝与聚集表型）的实际机制的深入了解。在这篇综述中，我们描述了促凝 COAT 血小板的表型特征，详细介绍了促凝反应机制的现有知识，并讨论了这种二分多样化的可能驱动因素，特别是解决了血小板环境在体内血栓形成过程中的影响。
