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1.
Int J Mol Sci ; 23(22)2022 Nov 17.
Article in English | MEDLINE | ID: covidwho-2116210

ABSTRACT

Coronavirus disease-19 (COVID-19) patients are prone to thrombotic complications that may increase morbidity and mortality. These complications are thought to be driven by endothelial activation and tissue damage promoted by the systemic hyperinflammation associated with COVID-19. However, the exact mechanisms contributing to these complications are still unknown. To identify additional mechanisms contributing to the aberrant clotting observed in COVID-19 patients, we analyzed platelets from COVID-19 patients compared to those from controls using mass spectrometry. We identified increased serum amyloid A (SAA) levels, an acute-phase protein, on COVID-19 patients' platelets. In addition, using an in vitro adhesion assay, we showed that healthy platelets adhered more strongly to wells coated with COVID-19 patient serum than to wells coated with control serum. Furthermore, inhibitors of integrin aIIbß3 receptors, a mediator of platelet-SAA binding, reduced platelet adhesion to recombinant SAA and to wells coated with COVID-19 patient serum. Our results suggest that SAA may contribute to the increased platelet adhesion observed in serum from COVID-19 patients. Thus, reducing SAA levels by decreasing inflammation or inhibiting SAA platelet-binding activity might be a valid approach to abrogate COVID-19-associated thrombotic complications.


Subject(s)
COVID-19 , Thrombosis , Humans , Serum Amyloid A Protein/metabolism , COVID-19/complications , Platelet Adhesiveness , Blood Platelets/metabolism , Thrombosis/etiology , Thrombosis/metabolism , Integrins/metabolism , Tissue Adhesions
2.
J Thromb Haemost ; 20(12): 2909-2920, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-2038140

ABSTRACT

BACKGROUND: Thrombogenicity is a known complication of COVID-19, resulting from SARS-CoV-2 infection, with significant effects on morbidity and mortality. OBJECTIVE: We aimed to better understand the effects of COVID-19 on fibrinogen and the resulting effects on clot structure, formation, and degradation. METHODS: Fibrinogen isolated from COVID-19 patients and uninfected subjects was used to form uniformly concentrated clots (2 mg/ml), which were characterized using confocal microscopy, scanning electron microscopy, atomic force microscopy, and endogenous and exogenous fibrinolysis assays. Neuraminidase digestion and subsequent NANA assay were used to quantify sialic acid residue presence; clots made from the desialylated fibrinogen were then assayed similarly to the original fibrinogen clots. RESULTS: Clots made from purified fibrinogen from COVID-19 patients were shown to be significantly stiffer and denser than clots made using fibrinogen from noninfected subjects. Endogenous and exogenous fibrinolysis assays demonstrated that clot polymerization and degradation dynamics were different for purified fibrinogen from COVID-19 patients compared with fibrinogen from noninfected subjects. Quantification of sialic acid residues via the NANA assay demonstrated that SARS-CoV-2-positive fibrinogen samples contained significantly more sialic acid. Desialylation via neuraminidase digestion resolved differences in clot density. Desialylation did not normalize differences in polymerization, but did affect rate of exogenous fibrinolysis. DISCUSSION: These differences noted in purified SARS-CoV-2-positive clots demonstrate that structural differences in fibrinogen, and not just differences in gross fibrinogen concentration, contribute to clinical differences in thrombotic features associated with COVID-19. These structural differences are at least in part mediated by differential sialylation.


Subject(s)
COVID-19 , Hemostatics , Thrombosis , Humans , Fibrinogen/metabolism , Fibrin/chemistry , N-Acetylneuraminic Acid , Polymerization , Neuraminidase , SARS-CoV-2 , Fibrinolysis , Thrombosis/metabolism
3.
Front Immunol ; 13: 953195, 2022.
Article in English | MEDLINE | ID: covidwho-1990285

ABSTRACT

Acute lung injury (ALI) is a heterogeneous inflammatory condition associated with high morbidity and mortality. Neutrophils play a key role in the development of different forms of ALI, and the release of neutrophil extracellular traps (NETs) is emerging as a common pathogenic mechanism. NETs are essential in controlling pathogens, and their defective release or increased degradation leads to a higher risk of infection. However, NETs also contain several pro-inflammatory and cytotoxic molecules than can exacerbate thromboinflammation and lung tissue injury. To reduce NET-mediated lung damage and inflammation, DNase is frequently used in preclinical models of ALI due to its capability of digesting NET DNA scaffold. Moreover, recent advances in neutrophil biology led to the development of selective NET inhibitors, which also appear to reduce ALI in experimental models. Here we provide an overview of the role of NETs in different forms of ALI discussing existing gaps in our knowledge and novel therapeutic approaches to modulate their impact on lung injury.


Subject(s)
Acute Lung Injury , Extracellular Traps , Thrombosis , Acute Lung Injury/pathology , Extracellular Traps/metabolism , Humans , Inflammation/metabolism , Neutrophils/metabolism , Thrombosis/metabolism
4.
J Hematol Oncol ; 15(1): 108, 2022 08 16.
Article in English | MEDLINE | ID: covidwho-1993373

ABSTRACT

The pathophysiology of COVID-19-associated coagulopathy is complex and not fully understood. SARS-CoV-2 spike protein (SP) may activate platelets and interact with fibrin(ogen). We aimed to investigate whether isolated SP can be present in clots retrieved in COVID-19 patients with acute ischemic stroke (by mechanical thrombectomy) and myocardial infarction. In this pilot study, we could detect SP, but not nucleocapsid protein, on platelets of COVID-19 patients' thrombi. In addition, in all three COVID-19 thrombi analyzed for molecular biology, no SARS-CoV-2 RNA could be detected by real-time polymerase chain reaction. These data could support the hypothesis that free SP, besides the whole virus, may be the trigger of platelet activation and clot formation in COVID-19.


Subject(s)
COVID-19 , Ischemic Stroke , Thrombosis , COVID-19/complications , Humans , Pilot Projects , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Thrombosis/etiology , Thrombosis/metabolism
5.
Expert Rev Hematol ; 15(8): 727-745, 2022 08.
Article in English | MEDLINE | ID: covidwho-1978157

ABSTRACT

INTRODUCTION: COVID-19 is associated to an increased risk of thrombosis, as a result of a complex process that involves the activation of vascular and circulating cells, the release of soluble inflammatory and thrombotic mediators and blood clotting activation. AREAS COVERED: This article reviews the pathophysiological role of platelets, neutrophils, and the endothelium, and of their interactions, in the thrombotic complications of COVID-19 patients, and the current and future therapeutic approaches targeting these cell types. EXPERT OPINION: Virus-induced platelet, neutrophil, and endothelial cell changes are crucial triggers of the thrombotic complications and of the adverse evolution of COVID-19. Both the direct interaction with the virus and the associated cytokine storm concur to trigger cell activation in a classical thromboinflammatory vicious circle. Although heparin has proven to be an effective prophylactic and therapeutic weapon for the prevention and treatment of COVID-19-associated thrombosis, it acts downstream of the cascade of events triggered by SARS-CoV-2. The identification of specific molecular targets interrupting the thromboinflammatory cascade upstream, and more specifically acting either on the interaction of SARS-CoV-2 with blood and vascular cells or on the specific signaling mechanisms associated with their COVID-19-associated activation, might theoretically offer greater protection with potentially lesser side effects.


Subject(s)
COVID-19 , Thrombosis , Blood Platelets/metabolism , COVID-19/complications , Endothelium/metabolism , Humans , Neutrophils/metabolism , SARS-CoV-2 , Thrombosis/etiology , Thrombosis/metabolism
6.
Arterioscler Thromb Vasc Biol ; 42(9): 1103-1112, 2022 09.
Article in English | MEDLINE | ID: covidwho-1950525

ABSTRACT

The activating interplay of thrombosis and inflammation (thromboinflammation) has been established as a major underlying pathway, driving not only cardiovascular disease but also autoimmune disease and most recently, COVID-19. Throughout the years, innate immune cells have emerged as important modulators of this process. As the most abundant white blood cell in humans, neutrophils are well-positioned to propel thromboinflammation. This includes their ability to trigger an organized cell death pathway with the release of decondensed chromatin structures called neutrophil extracellular traps. Decorated with histones and cytoplasmic and granular proteins, neutrophil extracellular traps exert cytotoxic, immunogenic, and prothrombotic effects accelerating disease progression. Distinct steps leading to extracellular DNA release (NETosis) require the activities of PAD4 (protein arginine deiminase 4) catalyzing citrullination of histones and are supported by neutrophil inflammasome. By linking the immunologic function of neutrophils with the procoagulant and proinflammatory activities of monocytes and platelets, PAD4 activity holds important implications for understanding the processes that fuel thromboinflammation. We will also discuss mechanisms whereby vascular occlusion in thromboinflammation depends on the interaction of neutrophil extracellular traps with ultra-large VWF (von Willebrand Factor) and speculate on the importance of PAD4 in neutrophil inflammasome assembly and neutrophil extracellular traps in thromboinflammatory diseases including atherosclerosis and COVID-19.


Subject(s)
Atherosclerosis , COVID-19 , Extracellular Traps , Thrombosis , Atherosclerosis/metabolism , Extracellular Traps/metabolism , Histones/metabolism , Humans , Inflammasomes/metabolism , Inflammation/metabolism , Neutrophils/metabolism , Thromboinflammation , Thrombosis/etiology , Thrombosis/metabolism , von Willebrand Factor/metabolism
7.
Int J Mol Sci ; 21(15)2020 Jul 27.
Article in English | MEDLINE | ID: covidwho-1934096

ABSTRACT

In physiology and pathophysiology the molecules involved in blood cell-blood cell and blood cell-endothelium interactions have been identified. Platelet aggregation and adhesion to the walls belonging to vessels involve glycoproteins (GP), GP llb and GP llla and the GP Ib-IX-V complex. Red blood cells (RBCs) in normal situations have little interaction with the endothelium. Abnormal adhesion of RBCs was first observed in sickle cell anemia involving vascular cell adhesion molecule (VCAM)-1, α4ß1, Lu/BCAM, and intercellular adhesion molecule (ICAM)-4. More recently RBC adhesion was found to be increased in retinal-vein occlusion (RVO) and in polycythemia vera (PV). The molecules which participate in this process are phosphatidylserine and annexin V in RVO, and phosphorylated Lu/BCAM and α5 laminin chain in PV. The additional adhesion in diabetes mellitus occurs due to the glycated RBC band 3 and the advanced glycation end-product receptors. The multiligand receptor binds advanced glycation end products (AGEs) or S100 calgranulins, or ß-amyloid peptide. This receptor for advanced glycation end products is known as RAGE. The binding to RAGE-activated endothelial cells leads to an inflammatory reaction and a prothrombotic state via NADPH activation and altered gene expression. RAGE blockade is a potential target for drugs preventing the deleterious consequences of RAGE activation.


Subject(s)
Cell Adhesion Molecules/metabolism , Endothelial Cells/metabolism , Erythrocytes/metabolism , Neoplasm Proteins/metabolism , Polycythemia Vera/metabolism , Retinal Vein Occlusion/metabolism , Cell Adhesion , Endothelial Cells/pathology , Erythrocytes/pathology , Glycation End Products, Advanced/metabolism , Humans , Polycythemia Vera/pathology , Receptor for Advanced Glycation End Products/metabolism , Retinal Vein Occlusion/pathology , Thrombosis/metabolism , Thrombosis/pathology
8.
Front Immunol ; 13: 879157, 2022.
Article in English | MEDLINE | ID: covidwho-1933664

ABSTRACT

During the COVID-19 pandemic, vaccination is the most important countermeasure. Pharmacovigilance concerns however emerged with very rare, but potentially disastrous thrombotic complications following vaccination with ChAdOx1. Platelet factor-4 antibody mediated vaccine-induced immune thrombotic thrombocytopenia (VITT) was described as an underlying mechanism of these thrombotic events. Recent work moreover suggests that mechanisms of immunothrombosis including neutrophil extracellular trap (NET) formation might be critical for thrombogenesis during VITT. In this study, we investigated blood and thrombus specimens of a female patient who suffered severe stroke due to VITT after vaccination with ChAdOx1 in comparison to 13 control stroke patients with similar clinical characteristics. We analyzed cerebral thrombi using histological examination, staining of complement factors, NET-markers, DNase and LL-37. In blood samples at the hyper-acute phase of stroke and 7 days later, we determined cell-free DNA, myeloperoxidase-histone complexes, DNase activity, myeloperoxidase activity, LL-37 and inflammatory cytokines. NET markers were identified in thrombi of all patients. Interestingly, the thrombus of the VITT-patient exclusively revealed complement factors and high amounts of DNase and LL-37. High DNase activity was also measured in blood, implying a disturbed NET-regulation. Furthermore, serum of the VITT-patient inhibited reactive oxygen species-dependent NET-release by phorbol-myristate-acetate to a lesser degree compared to controls, indicating either less efficient NET-inhibition or enhanced NET-induction in the blood of the VITT-patient. Additionally, the changes in specific cytokines over time were emphasized in the VITT-patient as well. In conclusion, insufficient resolution of NETs, e.g. by endogenous DNases or protection of NETs against degradation by embedded factors like the antimicrobial peptide LL-37 might thus be an important factor in the pathology of VITT besides increased NET-formation. On the basis of these findings, we discuss the potential implications of the mechanisms of disturbed NETs-degradation for diagnostic and therapeutic approaches in VITT-related thrombogenesis, other auto-immune disorders and beyond.


Subject(s)
COVID-19 , Extracellular Traps , Purpura, Thrombocytopenic, Idiopathic , Stroke , Thrombocytopenia , Thrombosis , Vaccines , Deoxyribonuclease I/metabolism , Deoxyribonucleases , Female , Humans , Neutrophils , Pandemics , Peroxidase/metabolism , Platelet Factor 4/metabolism , Purpura, Thrombocytopenic, Idiopathic/metabolism , Stroke/etiology , Stroke/metabolism , Thrombocytopenia/chemically induced , Thrombocytopenia/metabolism , Thrombosis/etiology , Thrombosis/metabolism , Vaccines/metabolism
9.
PLoS One ; 17(5): e0268296, 2022.
Article in English | MEDLINE | ID: covidwho-1910641

ABSTRACT

Severe coronavirus disease-19 (COVID-19) is characterized by vascular inflammation and thrombosis. We and others have proposed that the inflammatory response to coronavirus infection activates endothelial cells, leading to endothelial release of pro-thrombotic proteins. These mediators can trigger obstruction of the pulmonary microvasculature, leading to worsening oxygenation, acute respiratory distress syndrome, and death. In the current study, we tested the hypothesis that higher levels of biomarkers released from endothelial cells are associated with worse oxygenation in patients with COVID-19. We studied 83 participants aged 18-84 years with COVID-19 admitted to a single center. The severity of pulmonary disease was classified by oxygen requirement, including no oxygen requirement, low-flow oxygen, high-flow nasal cannula oxygen, mechanical ventilation, and death. We measured plasma levels of two proteins released by activated endothelial cells, von Willebrand Factor (VWF) antigen and soluble P-Selectin (sP-Sel), and a biomarker of systemic thrombosis, D-dimer. Additionally, we explored the association of endothelial biomarker levels with the levels of pro-inflammatory cytokine and chemokines, and vascular inflammation biomarkers. We found that levels of VWF, sP-sel, and D-dimer were increased in individuals with more severe COVID-19 pulmonary disease. Biomarkers of endothelial cell activation were also correlated with proinflammatory cytokines and chemokines. Taken together, our data demonstrate increased levels of VWF and sP-selectin are linked to the severity of lung disease in COVID-19 and correlated with biomarkers of inflammation and vascular inflammation. Our data support the concept that COVID-19 is a vascular disease which involves endothelial injury in the context of an inflammatory state.


Subject(s)
COVID-19 , Thrombosis , Biomarkers , Chemokines/metabolism , Endothelial Cells/metabolism , Endothelium, Vascular/metabolism , Humans , Inflammation/metabolism , Oxygen/metabolism , Thrombosis/metabolism , von Willebrand Factor/metabolism
10.
Int J Mol Sci ; 23(9)2022 Apr 27.
Article in English | MEDLINE | ID: covidwho-1809941

ABSTRACT

Neutrophil Extracellular Traps (NETs) are a contributing factor of vascular thrombosis and alveolar damage in COVID-19 patients. As enoxaparin is currently used to inhibit vascular thrombosis, this study aimed to investigate whether enoxaparin also reduced inflammation and NETs in COVID-19 patients. Patients with COVID-19 infection were classified into three groups: mild, moderate, and severe (n = 10 for all groups). Plasma was collected from patients and healthy donors (n = 10). Neutrophils isolated from healthy controls were incubated with COVID-19 or healthy plasma, and with or without enoxaparin pretreatment in vitro. Neutrophils and plasma isolated from patients treated with enoxaparin were also investigated. The levels of inflammatory cytokines and NET products such as dsDNA, NE, MPO-DNA and Histone-DNA complexes in plasma and supernatants were measured using immunofluorescence staining and ELISA kits. The expression of inflammatory signaling genes by neutrophils (RELA, SYK, ERK and PKC) was measured using real-time qPCR. The levels of NET products were elevated in the plasma of COVID-19 patients, particularly in the severe group (p < 0.01). Moreover, plasma from the severe group enhanced NET formation (p < 0.01) from neutrophils in vitro. Enoxaparin pretreatment in vitro decreased plasma-induced NETs in a dose-dependent manner and down-regulated the expression of inflammatory genes (p < 0.05). Patients treated with prophylactic enoxaparin showed lower inflammatory cytokine levels and expression of inflammatory genes (p < 0.05). Increased NETs were associated with the severity of COVID-19 infection, particularly in patients with severe pneumonia, and could be used as biomarkers to assess disease severity. Enoxaparin pretreatment inhibited NETs and reduced the expression of inflammatory cytokines, and these effects mostly persisted in patients treated with prophylactic enoxaparin.


Subject(s)
COVID-19 , Extracellular Traps , Thrombosis , Anti-Inflammatory Agents/pharmacology , COVID-19/drug therapy , Cytokines/metabolism , DNA/metabolism , Enoxaparin/pharmacology , Enoxaparin/therapeutic use , Extracellular Traps/metabolism , Humans , Neutrophils/metabolism , Thrombosis/drug therapy , Thrombosis/metabolism
11.
Blood Adv ; 6(17): 5085-5099, 2022 09 13.
Article in English | MEDLINE | ID: covidwho-1789100

ABSTRACT

Accumulating evidence into the pathogenesis of COVID-19 highlights a hypercoagulability state with high risk of life-threatening thromboembolic complications. However, the mechanisms of hypercoagulability and their link to hyperinflammation remain poorly understood. Here, we investigate functions and mechanisms of platelet activation and platelet-monocyte interactions in inflammatory amplification during SARS-CoV-2 infection. We used a combination of immunophenotyping, single-cell analysis, functional assays, and pharmacological approaches to gain insights on mechanisms. Critically ill patients with COVID-19 exhibited increased platelet-monocyte aggregates formation. We identified a subset of inflammatory monocytes presenting high CD16 and low HLA-DR expression as the subset mainly interacting with platelets during severe COVID-19. Single-cell RNA-sequencing analysis indicated enhanced fibrinogen receptor Mac-1 in monocytes from patients with severe COVID-19. Monocytes from patients with severe COVID-19 displayed increased platelet binding and hyperresponsiveness to P-selectin and fibrinogen with respect to tumor necrosis factor-α and interleukin-1ß secretion. Platelets were able to orchestrate monocyte responses driving tissue factor (TF) expression, inflammatory activation, and inflammatory cytokines secretion in SARS-CoV-2 infection. Platelet-monocyte interactions ex vivo and in SARS-CoV-2 infection model in vitro reciprocally activated monocytes and platelets, inducing the heightened secretion of a wide panel of inflammatory mediators. We identified platelet adhesion as a primary signaling mechanism inducing mediator secretion and TF expression, whereas TF signaling played major roles in amplifying inflammation by inducing proinflammatory cytokines, especially tumor necrosis factor-α and interleukin-1ß. Our data identify platelet-induced TF expression and activity at the crossroad of coagulation and inflammation in severe COVID-19.


Subject(s)
COVID-19 , Thrombophilia , Thrombosis , Blood Platelets/metabolism , Cytokines/metabolism , Humans , Inflammation/pathology , Interleukin-1beta/metabolism , Monocytes/metabolism , SARS-CoV-2 , Thromboinflammation , Thromboplastin/metabolism , Thrombosis/metabolism , Tumor Necrosis Factor-alpha/metabolism
12.
Biochem J ; 479(4): 537-559, 2022 02 17.
Article in English | MEDLINE | ID: covidwho-1705036

ABSTRACT

Post-acute sequelae of COVID (PASC), usually referred to as 'Long COVID' (a phenotype of COVID-19), is a relatively frequent consequence of SARS-CoV-2 infection, in which symptoms such as breathlessness, fatigue, 'brain fog', tissue damage, inflammation, and coagulopathies (dysfunctions of the blood coagulation system) persist long after the initial infection. It bears similarities to other post-viral syndromes, and to myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Many regulatory health bodies still do not recognize this syndrome as a separate disease entity, and refer to it under the broad terminology of 'COVID', although its demographics are quite different from those of acute COVID-19. A few years ago, we discovered that fibrinogen in blood can clot into an anomalous 'amyloid' form of fibrin that (like other ß-rich amyloids and prions) is relatively resistant to proteolysis (fibrinolysis). The result, as is strongly manifested in platelet-poor plasma (PPP) of individuals with Long COVID, is extensive fibrin amyloid microclots that can persist, can entrap other proteins, and that may lead to the production of various autoantibodies. These microclots are more-or-less easily measured in PPP with the stain thioflavin T and a simple fluorescence microscope. Although the symptoms of Long COVID are multifarious, we here argue that the ability of these fibrin amyloid microclots (fibrinaloids) to block up capillaries, and thus to limit the passage of red blood cells and hence O2 exchange, can actually underpin the majority of these symptoms. Consistent with this, in a preliminary report, it has been shown that suitable and closely monitored 'triple' anticoagulant therapy that leads to the removal of the microclots also removes the other symptoms. Fibrin amyloid microclots represent a novel and potentially important target for both the understanding and treatment of Long COVID and related disorders.


Subject(s)
Amyloid , Anticoagulants/therapeutic use , COVID-19 , Lung , SARS-CoV-2/metabolism , Thrombosis , Amyloid/blood , Amyloid/chemistry , COVID-19/blood , COVID-19/drug therapy , Fibrin/chemistry , Fibrin/metabolism , Humans , Lung/metabolism , Lung/virology , Thrombosis/drug therapy , Thrombosis/metabolism , Thrombosis/virology
13.
J Thromb Haemost ; 20(4): 919-928, 2022 04.
Article in English | MEDLINE | ID: covidwho-1626880

ABSTRACT

BACKGROUND: Resistance to fibrinolysis, levels of procoagulant/antifibrinolytic neutrophil extracellular traps (NETs), and the severity of acute ischemic stroke (AIS) are increased by COVID-19. Whether NETs are components of AIS thrombi from COVID-19 patients and whether COVID-19 impacts the susceptibility of these thrombi to thrombolytic treatments remain unknown, however. OBJECTIVES: We aimed to characterize AIS thrombi from COVID-19 patients by immunohistology and to compare their response to thrombolysis to that of AIS thrombi from non-COVID-19 patients. PATIENTS/METHODS: For this monocentric cohort study, 14 thrombi from COVID-19 AIS patients and 16 thrombi from non-COVID-19 patients, all recovered by endovascular therapy, were analyzed by immunohistology or subjected to ex vivo thrombolysis by tissue-type plasminogen (tPA)/plasminogen. RESULTS: COVID-19 AIS thrombi were rich in neutrophils and contained NETs, but not spike protein. Thrombolysis assays revealed a mean resistance profile to tPA/plasminogen of COVID-19 AIS thrombi similar to that of non-COVID-19 AIS thrombi. The addition of DNase 1 successfully improved thrombolysis by potentiating fibrinolysis irrespective of COVID-19 status. Levels of neutrophil, NETs, and platelet markers in lysis supernatants were comparable between AIS thrombi from non-COVID-19 and COVID-19 patients. CONCLUSIONS: These results show that COVID-19 does not impact NETs content or worsen fibrinolysis resistance of AIS thrombi, a therapeutic hurdle that could be overcome by DNase 1 even in the context of SARS-CoV-2 infection.


Subject(s)
Brain Ischemia , COVID-19 , Ischemic Stroke , Stroke , Thrombosis , Brain Ischemia/drug therapy , COVID-19/drug therapy , Cohort Studies , Fibrinolysis , Humans , SARS-CoV-2 , Stroke/drug therapy , Stroke/metabolism , Thrombolytic Therapy , Thrombosis/metabolism , Tissue Plasminogen Activator/therapeutic use
14.
Cells ; 11(2)2022 01 17.
Article in English | MEDLINE | ID: covidwho-1625673

ABSTRACT

Acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection continues to be a worldwide public health crisis. Among the several severe manifestations of this disease, thrombotic processes drive the catastrophic organ failure and mortality in these patients. In addition to a well-established cytokine storm associated with the disease, perturbations in platelets, endothelial cells, and the coagulation system are key in triggering systemic coagulopathy, involving both the macro- and microvasculatures of different organs. Of the several mechanisms that might contribute to dysregulation of these cells following SARS-CoV-2 infection, the current review focuses on the role of activated Janus kinase (JAK) signaling in augmenting thrombotic processes and organ dysfunction. The review concludes with presenting the current understanding and emerging controversies concerning the potential therapeutic applications of JAK inhibitors for ameliorating the inflammation-thrombosis phenotype in COVID-19 patients.


Subject(s)
COVID-19/metabolism , Endothelial Cells/metabolism , Janus Kinases/metabolism , SARS-CoV-2/metabolism , Signal Transduction , Thrombosis/metabolism , Cytokine Release Syndrome/metabolism , Cytokine Release Syndrome/virology , Endothelial Cells/virology , Humans , Thrombosis/virology
15.
Int J Mol Sci ; 22(24)2021 Dec 20.
Article in English | MEDLINE | ID: covidwho-1580687

ABSTRACT

COVID-19 infection is associated with a broad spectrum of presentations, but alveolar capillary microthrombi have been described as a common finding in COVID-19 patients, appearing as a consequence of a severe endothelial injury with endothelial cell membrane disruption. These observations clearly point to the identification of a COVID-19-associated coagulopathy, which may contribute to thrombosis, multi-organ damage, and cause of severity and fatality. One significant finding that emerges in prothrombotic abnormalities observed in COVID-19 patients is that the coagulation alterations are mainly mediated by the activation of platelets and intrinsically related to viral-mediated endothelial inflammation. Beyond the well-known role in hemostasis, the ability of platelets to also release various potent cytokines and chemokines has elevated these small cells from simple cell fragments to crucial modulators in the blood, including their inflammatory functions, that have a large influence on the immune response during infectious disease. Indeed, platelets are involved in the pathogenesis of acute lung injury also by promoting NET formation and affecting vascular permeability. Specifically, the deposition by activated platelets of the chemokine platelet factor 4 at sites of inflammation promotes adhesion of neutrophils on endothelial cells and thrombogenesis, and it seems deeply involved in the phenomenon of vaccine-induced thrombocytopenia and thrombosis. Importantly, the hyperactivated platelet phenotype along with evidence of cytokine storm, high levels of P-selectin, D-dimer, and, on the other hand, decreased levels of fibrinogen, von Willebrand factor, and thrombocytopenia may be considered suitable biomarkers that distinguish the late stage of COVID-19 progression in critically ill patients.


Subject(s)
Blood Platelets/physiology , COVID-19/blood , Thrombosis/pathology , Blood Coagulation , Blood Coagulation Disorders/etiology , Blood Platelets/metabolism , Blood Platelets/virology , COVID-19/metabolism , Cytokine Release Syndrome , Endothelial Cells/pathology , Fibrin Fibrinogen Degradation Products , Hemostasis , Humans , Inflammation , Phenotype , Platelet Activation/physiology , SARS-CoV-2/metabolism , SARS-CoV-2/pathogenicity , Thrombocytopenia/metabolism , Thrombosis/metabolism , Thrombosis/virology
16.
JCI Insight ; 7(2)2022 01 25.
Article in English | MEDLINE | ID: covidwho-1571524

ABSTRACT

Acute cardiac injury is prevalent in critical COVID-19 and associated with increased mortality. Its etiology remains debated, as initially presumed causes - myocarditis and cardiac necrosis - have proved uncommon. To elucidate the pathophysiology of COVID-19-associated cardiac injury, we conducted a prospective study of the first 69 consecutive COVID-19 decedents at CUIMC in New York City. Of 6 acute cardiac histopathologic features, presence of microthrombi was the most commonly detected among our cohort. We tested associations of cardiac microthrombi with biomarkers of inflammation, cardiac injury, and fibrinolysis and with in-hospital antiplatelet therapy, therapeutic anticoagulation, and corticosteroid treatment, while adjusting for multiple clinical factors, including COVID-19 therapies. Higher peak erythrocyte sedimentation rate and C-reactive protein were independently associated with increased odds of microthrombi, supporting an immunothrombotic etiology. Using single-nuclei RNA-sequencing analysis on 3 patients with and 4 patients without cardiac microthrombi, we discovered an enrichment of prothrombotic/antifibrinolytic, extracellular matrix remodeling, and immune-potentiating signaling among cardiac fibroblasts in microthrombi-positive, relative to microthrombi-negative, COVID-19 hearts. Non-COVID-19, nonfailing hearts were used as reference controls. Our study identifies a specific transcriptomic signature in cardiac fibroblasts as a salient feature of microthrombi-positive COVID-19 hearts. Our findings warrant further mechanistic study as cardiac fibroblasts may represent a potential therapeutic target for COVID-19-associated cardiac microthrombi.


Subject(s)
COVID-19 , Heart Injuries , RNA-Seq , SARS-CoV-2/metabolism , Thrombosis , Adult , Aged , Aged, 80 and over , COVID-19/genetics , COVID-19/metabolism , COVID-19/pathology , Female , Heart Injuries/genetics , Heart Injuries/metabolism , Heart Injuries/pathology , Humans , Male , Middle Aged , Myocardium/metabolism , Myocardium/pathology , Prospective Studies , Thrombosis/genetics , Thrombosis/metabolism , Thrombosis/pathology
17.
FASEB J ; 35(12): e21969, 2021 12.
Article in English | MEDLINE | ID: covidwho-1532548

ABSTRACT

Several evidence suggests that, in addition to the respiratory tract, also the gastrointestinal tract is a main site of severe acute respiratory syndrome CoronaVirus 2 (SARS-CoV-2) infection, as an example of a multi-organ vascular damage, likely associated with poor prognosis. To assess mechanisms SARS-CoV-2 responsible of tissue infection and vascular injury, correlating with thrombotic damage, specimens of the digestive tract positive for SARS-CoV-2 nucleocapsid protein were analyzed deriving from three patients, negative to naso-oro-pharyngeal swab for SARS-CoV-2. These COVID-19-negative patients came to clinical observation due to urgent abdominal surgery that removed different sections of the digestive tract after thrombotic events. Immunohistochemical for the expression of SARS-CoV-2 combined with a panel of SARS-CoV-2 related proteins angiotensin-converting enzyme 2 receptor, cluster of differentiation 147 (CD147), human leukocyte antigen-G (HLA-G), vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 was performed. Tissue samples were also evaluated by electron microscopy for ultrastructural virus localization and cell characterization. The damage of the tissue was assessed by ultrastructural analysis. It has been observed that CD147 expression levels correlate with SARS-CoV-2 infection extent, vascular damage and an increased expression of VEGF and thrombosis. The confirmation of CD147 co-localization with SARS-CoV-2 Spike protein binding on gastrointestinal tissues and the reduction of the infection level in intestinal epithelial cells after CD147 neutralization, suggest CD147 as a possible key factor for viral susceptibility of gastrointestinal tissue. The presence of SARS-CoV-2 infection of gastrointestinal tissue might be consequently implicated in abdominal thrombosis, where VEGF might mediate the vascular damage.


Subject(s)
Basigin/metabolism , COVID-19/complications , Digestive System Diseases/pathology , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/metabolism , Thrombosis/pathology , Vascular Endothelial Growth Factor A/metabolism , Aged , Basigin/genetics , COVID-19/virology , Digestive System Diseases/genetics , Digestive System Diseases/metabolism , Digestive System Diseases/virology , Female , Humans , Male , Middle Aged , Prognosis , Spike Glycoprotein, Coronavirus/genetics , Thrombosis/genetics , Thrombosis/metabolism , Thrombosis/virology , Vascular Endothelial Growth Factor A/genetics
18.
Clin Appl Thromb Hemost ; 27: 10760296211051764, 2021.
Article in English | MEDLINE | ID: covidwho-1511654

ABSTRACT

The precise mechanisms of pathology in severe COVID-19 remains elusive. Current evidence suggests that inflammatory mediators are responsible for the manifestation of clinical symptoms that precedes a fatal response to infection. This review examines the nature of platelet activating factor and emphasizes the similarities between the physiological effects of platelet activating factor and the clinical complications of severe COVID-19.


Subject(s)
COVID-19/metabolism , Platelet Activating Factor/metabolism , Animals , COVID-19/complications , COVID-19/mortality , COVID-19/pathology , Humans , Inflammation/complications , Inflammation/metabolism , Inflammation/mortality , Inflammation/pathology , Multiple Organ Failure/complications , Multiple Organ Failure/metabolism , Multiple Organ Failure/mortality , Multiple Organ Failure/pathology , Respiratory Distress Syndrome/complications , Respiratory Distress Syndrome/metabolism , Respiratory Distress Syndrome/mortality , Respiratory Distress Syndrome/pathology , SARS-CoV-2/physiology , Severity of Illness Index , Thrombosis/complications , Thrombosis/metabolism , Thrombosis/mortality , Thrombosis/pathology
19.
Am J Pathol ; 192(1): 112-120, 2022 01.
Article in English | MEDLINE | ID: covidwho-1506166

ABSTRACT

Severe coronavirus disease 2019 (COVID-19) increases the risk of myocardial injury that contributes to mortality. This study used multiparameter immunofluorescence to extensively examine heart autopsy tissue of 7 patients who died of COVID-19 compared to 12 control specimens, with or without cardiovascular disease. Consistent with prior reports, no evidence of viral infection or lymphocytic infiltration indicative of myocarditis was found. However, frequent and extensive thrombosis was observed in large and small vessels in the hearts of the COVID-19 cohort, findings that were infrequent in controls. The endothelial lining of thrombosed vessels typically lacked evidence of cytokine-mediated endothelial activation, assessed as nuclear expression of transcription factors p65 (RelA), pSTAT1, or pSTAT3, or evidence of inflammatory activation assessed by expression of intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), tissue factor, or von Willebrand factor (VWF). Intimal EC lining was also generally preserved with little evidence of cell death or desquamation. In contrast, there were frequent markers of neutrophil activation within myocardial thrombi in patients with COVID-19, including neutrophil-platelet aggregates, neutrophil-rich clusters within macrothrombi, and evidence of neutrophil extracellular trap (NET) formation. These findings point to alterations in circulating neutrophils rather than in the endothelium as contributors to the increased thrombotic diathesis in the hearts of COVID-19 patients.


Subject(s)
COVID-19 , Coronary Vessels , Myocarditis , Myocardium , SARS-CoV-2/metabolism , Thrombosis , Aged , Aged, 80 and over , Blood Platelets/metabolism , Blood Platelets/pathology , COVID-19/metabolism , COVID-19/pathology , Coronary Vessels/metabolism , Coronary Vessels/pathology , Endothelium, Vascular/metabolism , Endothelium, Vascular/pathology , Female , Gene Expression Regulation , Humans , Male , Middle Aged , Myocarditis/metabolism , Myocarditis/pathology , Myocardium/metabolism , Myocardium/pathology , Neutrophil Activation , Neutrophils/metabolism , Neutrophils/pathology , Platelet Aggregation , Thrombosis/metabolism , Thrombosis/pathology
20.
Int J Biol Macromol ; 193(Pt B): 1124-1129, 2021 Dec 15.
Article in English | MEDLINE | ID: covidwho-1487744

ABSTRACT

Thrombotic complication has been an important symptom in critically ill patients with COVID-19. It has not been clear whether the virus spike (S) protein can directly induce blood coagulation in addition to inflammation. Heparan sulfate (HS)/heparin, a key factor in coagulation process, was found to bind SARS-CoV-2 S protein with high affinity. Herein, we found that the S protein can competitively inhibit the bindings of antithrombin and heparin cofactor II to heparin/HS, causing abnormal increase in thrombin activity. SARS-CoV-2 S protein at a similar concentration (~10 µg/mL) as the viral load in critically ill patients can cause directly blood coagulation and thrombosis in zebrafish model. Furthermore, exogenous heparin/HS can significantly reduce coagulation caused by S protein, pointing to a potential new direction to elucidate the etiology of the virus and provide fundamental support for anticoagulant therapy especially for the COVID-19 critically ill patients.


Subject(s)
Blood Coagulation , Heparitin Sulfate , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Thrombosis/metabolism , Animals , Heparitin Sulfate/chemistry , Heparitin Sulfate/metabolism , Humans , Mice , Protein Binding , SARS-CoV-2/chemistry , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism
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