key: cord-285349-850n4pot authors: Omarjee, Loukman; Meilhac, Olivier; Perrot, Frédérique; Janin, Anne; Mahe, Guillaume title: Can Ticagrelor be used to prevent sepsis-induced coagulopathy in COVID-19? date: 2020-05-21 journal: Clin Immunol DOI: 10.1016/j.clim.2020.108468 sha: doc_id: 285349 cord_uid: 850n4pot nan . We read with great interest this article. The authors mentioned that "coagulation dysfunction, thrombosis and pulmonary embolism have been observed in severe COVID-19 [1] ." We would like to discuss a potential therapeutic strategy to prevent sepsis-induced coagulopathy (SIC) in coronavirus disease 2019 (COVID-19). The outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread into a pandemic [1] . Mortality is high in intensive care unit (ICU), and associated with comorbidities such as diabetes mellitus, chronic kidney disease, chronic obstructive pulmonary disease, or cardiovascular disease [2] . COVID-19 is also associated with sepsis-induced coagulopathy (SIC) leading to dissemina ted intravascular coagulation (DIC) [3] . In COVID-19, elevation of D-dimer and fibrin/fibrino ge n degradation products are the initial coagulopathy markers found [3] . COVID-19 patients also meet Virchow's triad criteria for thrombosis: i) endothelial injury, ii) hypercoagulability and iii) venous stasis. Two fibrinolysis markers, D-Dimer and fibrin degradation products, are the hallmarks of SIC-related mortality [3] . Low molecular weight heparin (LMWH) is a commonly used anticoagulant to prevent DIC and venous thromboembolism, but its efficiency in DIC remains controversial [3] . LMWH also exposes to the risk of heparin induced thrombocytopenia, an immune-mediated syndrome characterized by thrombocytopenia and a high risk for venous or arterial thrombosis [4] . Platelets modulate hemostasis and immune responses via interactions with immune cells, through secretion of immune-modulators and cell-cell interactions [5] . Platelets activate leukocytes through cell-cell interactions involving adhesion molecules such as P-selectin, a glycoprotein that, upon cell activation, is rapidly translocated from cytoplasmic α-granules to the cell surface [5] . Platelets-Leukocytes interactions are important in the pathogenesis of sepsis, and Platelets-Neutrophils Aggregates (PNA) and P-selectin secretion are altered in septic patients [5] . The platelet P2Y12, a G protein-coupled receptor that are expressed on platelet membranes for adenosine 5'diphosphate (ADP), plays a central role in platelet function, hemostasis, and thrombosis [5] (Figure 1 ). The P2Y12 receptor is involved in platelet aggregation and is thus a biological target for the treatment of thromboembolisms and other clotting disorders [5] such as SIC and DIC. Ticagrelor is an orally administered platelet aggregation inhibitor with a cyclopentyltriazolopyrimidine structure [5] (Figure 1 ). It is a selective reversible P2Y12 receptor antagonis t, which prevents P2Y12-mediated and ADP-mediated platelet activation and aggregation [5] . In addition, several studies indicate that ticagrelor may have pleiotropic effects in addition to its anti-platelet properties [6] . Here we aim at discussing the potential use of Ticagrelor in COVID-19, to reduce PNA, neutrophil extracellular traps (NETs) release, and vascular leakage. Ticagrelor was approved for the prevention of severe cardiovascular events among patients with coronary ischemia or ischemic stroke [7] . J o u r n a l P r e -p r o o f Journal Pre-proof Experimental models of sepsis and human clinical trials have also shown that platelet receptor P2Y12 inhibition reduced sepsis-induced mortality [7] [8] [9] [10] . In models of LPS-induced inflammation, Ticagrelor reduced cytokines IL-6, TNF-α, MCP-1 and IL-8 [10] , and mortality [9] . In a model of intra-abdominal sepsis, Ticagrelor reduced sepsis-induced lung injur y, neutrophils pulmonary infiltration, PNA formation, platelet activation and thrombocytope nia [8] . In the PLATelet inhibition and patient Outcomes (PLATO) study, Ticagrelor reduced mortality risk following pulmonary adverse events such as bacterial kung infection and sepsis in acute coronary syndrome patients [7] . According to neutrophils are a first-line defense against bacterial lung infection, a potential mechanism by which ticagrelor could influence host defense against bacterial lung infection is inhibition of cellular uptake of adenosine, a known regulator of neutrophil chemotaxis and phagocytosis [6, 7] . In the human clinical trial "Targeting Platelet-Leukocyte Aggregates in Pneumonia with Ticagrelor (XANTHIPPE) study", Ticagrelor reduced platelet-leucocyte interactions, and IL-6 levels within 24hrs in patients with pneumonia [9] . It also limited NET release, thus improving lung function, and reducing vascular leakage and oxygen need [9] . The findings indicate a mechanistic link between platelets, leukocytes, and lung injury in settings of pneumonia and sepsis, and suggest possible therapeutic use of Ticagrelor to reduce complications. Ticagrelo r also decreased D-Dimer levels in healthy volunteers [11] . One important point in the safe use of Ticagrelor. Pulmonary hemorrhage has been reported under dual antiplatelet therapy: Ticagrelor plus aspirin [12] . To avoid an increased bleeding risk, randomized controlled trial showed a net benefit of aspirin-free antiplatelet therapy [13] . This was demonstrated in the XANTHIPPE study, since Ticagrelor use was safe with no major J o u r n a l P r e -p r o o f Journal Pre-proof bleeding reported [9] . COVID-19 is associated with coagulopathy through (Figure 1 ): i) endothelia l injury/dysfunction induced by the binding of SARS-CoV-2 to endothelial ACE2 receptor that leads to excess thrombin generation and fibrinolysis [14] ; ii) platelet activation that induces hypercoagulability and membrane receptor expression enabling PNA between platelets and leukocytes [15] ; iii) PNA formation that release pro-inflammatory cytokines, reactive oxygen species and NETs; iv) NETs released from activated neutrophils in response to infection suc h as SARS-CoV-2 can trap, and kill microorganisms [15] . They also activate platelets and coagulation, and contribute to thrombogenesis by forming a mesh with platelets and fibrin and accumulating coagulation factors such as Tissue Factor; v) Inflammation induced by NETcomponents (DNA, histone, and granule proteins including proteases such as elastase and prooxidant enzymes such as myeloperoxidase) also contribute to triggering cytokine release, oxidative stress and extracellular matrix proteolysis [15] . Cytokines and reactive oxygen species released by neutrophils can alter the endothelial barrier function, enhance leakage, and promote the development of tissue oedema and hypoxia [15] leading to acute respiratory distress and multiple organ dysfunction [14] . Therefore, when given at the early onset of COVID-19, Ticagrelor, through inhibition of platelet-neutrophil aggregates, NET release, and vascular leakage might prevent SIC, progression to DIC and associated morbi/mortality in COVID-19 patients. Ticagrelor could be a promised candidate to prevent SIC that it would be interesting to evaluate in a randomized clinical trial in COVID-19. Each author has agreed both to be personally accountable for the author's own contributio ns and to ensure that questions related to the accuracy or integrity of any part of the work, even ones in which the author was not personally involved, are appropriately investigated, resolved, and the resolution documented in the literature. COVID-19 pathophysiology: A review Interleukin-17A (IL-17A), a key molecule of innate and adaptive immunity, and its potential involvement in COVID-19-related thrombotic and vascular mechanisms Anticoagulant treatment is associated with decreased mortality in severe coronavirus disease 2019 patients with coagulopathy Heparin-Induced Thrombocytopenia P2Y 12 receptors: structure and function Ticagrelor potentiates adenosine-induced stimulation of neutrophil chemotaxis and phagocytosis Lower mortality following pulmonary adverse events and sepsis with ticagrelor compared to clopidogrel in the PLATO study Ticagrelor reduces neutrophil recruitment and lung damage in abdominal sepsis Ticagrelor Reduces Thromboinflammatory Markers in Patients With Pneumonia Inhibitors Reduce Systemic Inflammation and Its Prothrombotic Effects in an Experimenta l Human Model Differential Effects of Ticagrelor With or Without Aspirin on Platelet Reactivity and Coagulation Activation: A Randomized Trial in Healthy Volunteers Pneumonitis and pulmonar y haemorrhage after acute myocardial infarction for the GLOBAL LEADERS Trial Investigators, Benefit and Risks of Aspirin in Addition to Ticagrelor in Acute Coronary Syndromes: A Post Hoc Analysis of the Randomized GLOBAL LEADERS Trial Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease-2019 (COVID-19): The epidemic and the challenges Platelet-Neutrophil Interplay: Insights Into Neutrophil Extracellular Trap (NET)-Driven Coagulation in Infection The authors wish to thank Ms Hazel Chaouch for English language correction. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. All authors declare they have nothing to disclose, and no competing interests. The authors do hereby declare that all illustrations and figures in the manuscript are entirely original and do not require reprint permission.