Institute for Cardiovascular Prevention, Ludwig-Maximilians University Munich, Munich, Germany.
Thromb Haemost. 2011 Nov;106(5):827-38. doi: 10.1160/TH11-08-0592. Epub 2011 Oct 20.
Beyond obvious functions in haemostasis and thrombosis, platelets are considered to be essential in proinflammatory surroundings such as atherosclerosis, allergy, rheumatoid arthritis and even cancer. In atherosclerosis, platelets facilitate the recruitment of inflammatory cells towards the lesion sites and release a plethora of inflammatory mediators, thereby enriching and boosting the inflammatory milieu. Platelets do so by interacting with endothelial cells, circulating leukocytes (monocytes, neutrophils, dendritic cells, T-cells) and progenitor cells. This cross-talk enforces leukocyte activation, adhesion and transmigration. Furthermore, platelets are known to function in innate host defense through the release of antimicrobial peptides and the expression of pattern recognition receptors. In severe sepsis, platelets are able to trigger the formation of neutrophil extracellular traps (NETs), which bind and clear pathogens. The present antiplatelet therapies that target key pathways of platelet activation and aggregation therefore hold the potential to modulate platelet-derived immune functions by reducing cellular interactions of platelets with other immune components and by reducing the secretion of inflammatory proteins into the milieu. The objective of this review is to update and discuss the current perceptions of the platelet immune constituents and their prospect as therapeutic targets in an atherosclerotic setting.
除了在止血和血栓形成方面的明显功能外，血小板在动脉粥样硬化、过敏、类风湿关节炎甚至癌症等炎症环境中被认为是必不可少的。在动脉粥样硬化中，血小板促进炎症细胞向病变部位募集，并释放大量炎症介质，从而丰富和增强炎症微环境。血小板通过与内皮细胞、循环白细胞（单核细胞、中性粒细胞、树突状细胞、T 细胞）和祖细胞相互作用来实现这一点。这种细胞间通讯促进白细胞的激活、黏附和迁移。此外，血小板通过释放抗菌肽和表达模式识别受体来参与先天宿主防御。在严重脓毒症中，血小板能够触发中性粒细胞胞外诱捕网（NETs）的形成，NETs可以结合并清除病原体。目前针对血小板激活和聚集关键途径的抗血小板治疗方法有可能通过减少血小板与其他免疫成分的细胞相互作用以及减少炎症蛋白分泌到细胞外基质中来调节血小板衍生的免疫功能。本综述的目的是更新和讨论血小板免疫成分的最新认识及其作为动脉粥样硬化治疗靶点的前景。
