Platelet adherence during inflammatory diseases. Quantity matters!

Atherosclerosis is a leading cause of mortalities worldwide and the primary cause of cardiovascular disease. Percutaneous coronary intervention followed by stent implantation is the main procedure to prevent the occurrence of adverse cardiac events. Despite advances in percutaneous coronary intervention, many patients experience recurrent adverse cardiac events. The recruitment of reparative monocytes to the endothelium, which is mediated by platelets, reduces the recurrence of adverse cardiac event. Hence, we studied the influence of increased platelet binding to monocytes during atherosclerosis. We found that the a high number of platelets per monocyte increases monocyte recruitment to endothelial cells. Since monocytes stimulate vascular repair, we studied whether a high number of platelets per monocyte was associated with the recurrence of adverse cardiac events in patients after percutaneous coronary intervention induced vascular damage. We are the first to show that a high number of platelets per monocyte is associated with a decreased recurrence of adverse cardiac events. Our findings show that the number of platelets per monocyte is a mechanism that guides monocytes to the endothelium and the platelet density per monocyte is a novel predictor adverse cardiac events in patients after PCI. Our results may imply that a high number of platelets per monocyte protects patients with cardiovascular disease against the recurrence of adverse cardiac events.