The interface of hemostasis and inflammation: endothelial-platelet dynamics in thrombosis
1Boston Children's Hospital.
Purpose Of Review:
This review summarizes current understanding of platelet-endothelial contributions to thrombosis, emphasizing molecular crosstalk [von Willebrand factor (VWF)/ADAMTS13 balance, P-selectin, platelet glycoprotein VI (GPVI), integrins, extracellular vesicles, neutrophil extracellular traps (NETs)], high-risk clinical settings, and translational advances. Highlighting GPVI-directed therapeutics, the VWF/ADAMTS13 axis in COVID-19, and opportunities and challenges for targeting the platelet-endothelial interface.
Recent Findings:
Clinical and translational studies support the safety and potential efficacy of targeting platelet-endothelial interfaces. GPVI inhibitors (Glenzocimab, Revacept) have advanced through phase I/II studies with reassuring bleeding profiles and suggest benefit in ischemic stroke and lesion-directed settings. Direct interruption of platelet-VWF interactions (Caplacizumab) is established in immune thrombotic thrombocytopenic purpura (TTP), while studies show a persistent VWF/ADAMTS13 imbalance in severe COVID-19 and inflammatory states linked to microthrombosis and worse outcomes. Antiadhesion strategies (P-selectin blockade) and modulators of immunothrombosis (NET inhibitors, targeting extracellular vesicle) are also in evaluation.
Summary:
Targeting platelet-endothelial crosstalk has potential to reduce pathologic thrombosis while preserving hemostasis. Clinical proof of principle exists for focused approaches (anti-VWF in TTP; P-selectin blockade in vaso-occlusion; emerging GPVI inhibitors). Priorities are: defining disease contexts and timing where interface targeting is effective; validating biomarkers (VWF/ADAMTS13 ratio, soluble P-selectin, platelet activation signatures) for patient selection; and conducting adequately powered trials with rigorous bleeding endpoints.
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