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1.
Semin Respir Crit Care Med ; 42(2): 316-326, 2021 04.
Article in English | MEDLINE | ID: covidwho-1493288

ABSTRACT

Venous thromboembolism, occlusion of dialysis catheters, circuit thrombosis in extracorporeal membrane oxygenation (ECMO) devices, acute limb ischemia, and isolated strokes, all in the face of prophylactic and even therapeutic anticoagulation, are features of novel coronavirus disease 2019 (COVID-19) coagulopathy. It seems well established at this time that a COVID-19 patient deemed sick enough to be hospitalized, should receive at least prophylactic dose anticoagulation. However, should some hospitalized patients have dosage escalation to intermediate dose? Should some be considered for full-dose anticoagulation without a measurable thromboembolic event and how should that anticoagulation be monitored? Should patients receive postdischarge anticoagulation and with what medication and for how long? What thrombotic issues are related to the various medications being used to treat this coagulopathy? Is antiphospholipid antibody part of this syndrome? What is the significance of isolated ischemic stroke and limb ischemia in this disorder and how does this interface with the rest of the clinical and laboratory features of this disorder? The aims of this article are to explore these questions and interpret the available data based on the current evidence.


Subject(s)
Anticoagulants/administration & dosage , COVID-19/drug therapy , Thrombophilia/drug therapy , Thrombosis/prevention & control , Venous Thromboembolism/prevention & control , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/therapeutic use , Alanine/analogs & derivatives , Alanine/therapeutic use , Ambulatory Care , Antibodies, Antiphospholipid/immunology , Antibodies, Monoclonal, Humanized/therapeutic use , Antirheumatic Agents/therapeutic use , Antiviral Agents/therapeutic use , COVID-19/blood , COVID-19/complications , COVID-19/immunology , COVID-19/therapy , Dose-Response Relationship, Drug , Drug Combinations , Duration of Therapy , Glucocorticoids/therapeutic use , Hospitalization , Humans , Hydroxychloroquine/therapeutic use , Immunization, Passive , Lopinavir/therapeutic use , Ritonavir/therapeutic use , SARS-CoV-2 , Thrombolytic Therapy , Thrombophilia/blood , Thrombophilia/etiology , Thrombosis/drug therapy , Thrombosis/immunology , Venous Thromboembolism/drug therapy , Venous Thromboembolism/immunology
2.
Blood ; 138(16): 1481-1489, 2021 10 21.
Article in English | MEDLINE | ID: covidwho-1484294

ABSTRACT

A subset of patients with coronavirus disease 2019 (COVID-19) become critically ill, suffering from severe respiratory problems and also increased rates of thrombosis. The causes of thrombosis in severely ill patients with COVID-19 are still emerging, but the coincidence of critical illness with the timing of the onset of adaptive immunity could implicate an excessive immune response. We hypothesized that platelets might be susceptible to activation by anti-severe acute respiratory syndrome coronavirus 2 (anti-SARS-CoV-2) antibodies and might contribute to thrombosis. We found that immune complexes containing recombinant SARS-CoV-2 spike protein and anti-spike immunoglobulin G enhanced platelet-mediated thrombosis on von Willebrand factor in vitro, but only when the glycosylation state of the Fc domain was modified to correspond with the aberrant glycosylation previously identified in patients with severe COVID-19. Furthermore, we found that activation was dependent on FcγRIIA, and we provide in vitro evidence that this pathogenic platelet activation can be counteracted by the therapeutic small molecules R406 (fostamatinib) and ibrutinib, which inhibit tyrosine kinases Syk and Btk, respectively, or by the P2Y12 antagonist cangrelor.


Subject(s)
Blood Platelets/pathology , COVID-19/complications , Immunoglobulin G/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/metabolism , Thrombosis/pathology , von Willebrand Factor/metabolism , Antibodies, Viral/blood , Antibodies, Viral/immunology , Antigen-Antibody Complex/immunology , Blood Platelets/immunology , Blood Platelets/metabolism , COVID-19/immunology , COVID-19/virology , Glycosylation , Humans , Platelet Activation/immunology , Thrombosis/immunology , Thrombosis/virology , von Willebrand Factor/genetics
3.
Cells ; 10(9)2021 08 26.
Article in English | MEDLINE | ID: covidwho-1458477

ABSTRACT

The enlightenment of the formation of neutrophil extracellular traps (NETs) as a part of the innate immune system shed new insights into the pathologies of various diseases. The initial idea that NETs are a pivotal defense structure was gradually amended due to several deleterious effects in consecutive investigations. NETs formation is now considered a double-edged sword. The harmful effects are not limited to the induction of inflammation by NETs remnants but also include occlusions caused by aggregated NETs (aggNETs). The latter carries the risk of occluding tubular structures like vessels or ducts and appear to be associated with the pathologies of various diseases. In addition to life-threatening vascular clogging, other occlusions include painful stone formation in the biliary system, the kidneys, the prostate, and the appendix. AggNETs are also prone to occlude the ductal system of exocrine glands, as seen in ocular glands, salivary glands, and others. Last, but not least, they also clog the pancreatic ducts in a murine model of neutrophilia. In this regard, elucidating the mechanism of NETs-dependent occlusions is of crucial importance for the development of new therapeutic approaches. Therefore, the purpose of this review is to address the putative mechanisms of NETs-associated occlusions in the pathogenesis of disease, as well as prospective treatment modalities.


Subject(s)
Embolism/immunology , Extracellular Traps/physiology , Thrombosis/immunology , Animals , Body Fluids/immunology , Body Fluids/physiology , Embolism/physiopathology , Extracellular Traps/immunology , Extracellular Traps/metabolism , Humans , Inflammation/pathology , Neutrophils/immunology , Prospective Studies , Thrombosis/physiopathology
4.
Int J Mol Sci ; 22(19)2021 Oct 06.
Article in English | MEDLINE | ID: covidwho-1457948

ABSTRACT

Novel coronavirus SARS-CoV-2 has resulted in a global pandemic with worldwide 6-digit infection rates and thousands of death tolls daily. Enormous efforts are undertaken to achieve high coverage of immunization to reach herd immunity in order to stop the spread of SARS-CoV-2 infection. Several SARS-CoV-2 vaccines based on mRNA, viral vectors, or inactivated SARS-CoV-2 virus have been approved and are being applied worldwide. However, the recent increased numbers of normally very rare types of thromboses associated with thrombocytopenia have been reported, particularly in the context of the adenoviral vector vaccine ChAdOx1 nCoV-19 from Astra Zeneca. The statistical prevalence of these side effects seems to correlate with this particular vaccine type, i.e., adenoviral vector-based vaccines, but the exact molecular mechanisms are still not clear. The present review summarizes current data and hypotheses for molecular and cellular mechanisms into one integrated hypothesis indicating that coagulopathies, including thromboses, thrombocytopenia, and other related side effects, are correlated to an interplay of the two components in the vaccine, i.e., the spike antigen and the adenoviral vector, with the innate and immune systems, which under certain circumstances can imitate the picture of a limited COVID-19 pathological picture.


Subject(s)
COVID-19 Vaccines/adverse effects , COVID-19/prevention & control , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Thrombocytopenia/etiology , Thrombosis/etiology , Adenoviridae/immunology , Animals , COVID-19/immunology , COVID-19 Vaccines/immunology , Genetic Vectors/adverse effects , Genetic Vectors/immunology , Humans , Purpura, Thrombocytopenic, Idiopathic/etiology , Purpura, Thrombocytopenic, Idiopathic/immunology , Spike Glycoprotein, Coronavirus/adverse effects , Thrombocytopenia/immunology , Thrombosis/immunology , Vaccination/adverse effects
5.
Front Immunol ; 12: 752612, 2021.
Article in English | MEDLINE | ID: covidwho-1456293

ABSTRACT

Background: Lymphopenia and the neutrophil/lymphocyte ratio may have prognostic value in COVID-19 severity. Objective: We investigated neutrophil subsets and functions in blood and bronchoalveolar lavage (BAL) of COVID-19 patients on the basis of patients' clinical characteristics. Methods: We used a multiparametric cytometry profiling based to mature and immature neutrophil markers in 146 critical or severe COVID-19 patients. Results: The Discovery study (38 patients, first pandemic wave) showed that 80% of Intensive Care Unit (ICU) patients develop strong myelemia with CD10-CD64+ immature neutrophils (ImNs). Cellular profiling revealed three distinct neutrophil subsets expressing either the lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), the interleukin-3 receptor alpha (CD123), or programmed death-ligand 1 (PD-L1) overrepresented in ICU patients compared to non-ICU patients. The proportion of LOX-1- or CD123-expressing ImNs is positively correlated with clinical severity, cytokine storm (IL-1ß, IL-6, IL-8, TNFα), acute respiratory distress syndrome (ARDS), and thrombosis. BALs of patients with ARDS were highly enriched in LOX-1-expressing ImN subsets and in antimicrobial neutrophil factors. A validation study (118 patients, second pandemic wave) confirmed and strengthened the association of the proportion of ImN subsets with disease severity, invasive ventilation, and death. Only high proportions of LOX-1-expressing ImNs remained strongly associated with a high risk of severe thrombosis independently of the plasma antimicrobial neutrophil factors, suggesting an independent association of ImN markers with their functions. Conclusion: LOX-1-expressing ImNs may help identifying COVID-19 patients at high risk of severity and thrombosis complications.


Subject(s)
COVID-19/complications , Neutrophils/immunology , Scavenger Receptors, Class E/genetics , Thrombosis/etiology , Adult , Aged , B7-H1 Antigen/genetics , B7-H1 Antigen/immunology , Bronchoalveolar Lavage Fluid/immunology , COVID-19/genetics , COVID-19/immunology , COVID-19/virology , Critical Illness , Female , Humans , Interleukin-3 Receptor alpha Subunit/genetics , Interleukin-3 Receptor alpha Subunit/immunology , Interleukin-8/genetics , Interleukin-8/immunology , Male , Middle Aged , Respiratory Distress Syndrome/etiology , Respiratory Distress Syndrome/genetics , Respiratory Distress Syndrome/immunology , SARS-CoV-2/physiology , Scavenger Receptors, Class E/immunology , Thrombosis/genetics , Thrombosis/immunology
7.
J Clin Invest ; 130(11): 6151-6157, 2020 11 02.
Article in English | MEDLINE | ID: covidwho-1435146

ABSTRACT

Emerging data indicate that complement and neutrophils contribute to the maladaptive immune response that fuels hyperinflammation and thrombotic microangiopathy, thereby increasing coronavirus 2019 (COVID-19) mortality. Here, we investigated how complement interacts with the platelet/neutrophil extracellular traps (NETs)/thrombin axis, using COVID-19 specimens, cell-based inhibition studies, and NET/human aortic endothelial cell (HAEC) cocultures. Increased plasma levels of NETs, tissue factor (TF) activity, and sC5b-9 were detected in patients. Neutrophils of patients yielded high TF expression and released NETs carrying active TF. Treatment of control neutrophils with COVID-19 platelet-rich plasma generated TF-bearing NETs that induced thrombotic activity of HAECs. Thrombin or NETosis inhibition or C5aR1 blockade attenuated platelet-mediated NET-driven thrombogenicity. COVID-19 serum induced complement activation in vitro, consistent with high complement activity in clinical samples. Complement C3 inhibition with compstatin Cp40 disrupted TF expression in neutrophils. In conclusion, we provide a mechanistic basis for a pivotal role of complement and NETs in COVID-19 immunothrombosis. This study supports strategies against severe acute respiratory syndrome coronavirus 2 that exploit complement or NETosis inhibition.


Subject(s)
Betacoronavirus , Complement Membrane Attack Complex , Coronavirus Infections , Extracellular Traps , Neutrophils , Pandemics , Pneumonia, Viral , Thromboplastin , Thrombosis , Aged , Betacoronavirus/immunology , Betacoronavirus/metabolism , COVID-19 , Complement Activation/drug effects , Complement Membrane Attack Complex/immunology , Complement Membrane Attack Complex/metabolism , Coronavirus Infections/blood , Coronavirus Infections/immunology , Extracellular Traps/immunology , Extracellular Traps/metabolism , Female , Humans , Male , Middle Aged , Neutrophils/immunology , Neutrophils/metabolism , Peptides, Cyclic/pharmacology , Pneumonia, Viral/blood , Pneumonia, Viral/immunology , Receptor, Anaphylatoxin C5a/antagonists & inhibitors , Receptor, Anaphylatoxin C5a/blood , Receptor, Anaphylatoxin C5a/immunology , Respiratory Distress Syndrome/blood , Respiratory Distress Syndrome/immunology , Respiratory Distress Syndrome/virology , SARS-CoV-2 , Thrombin/immunology , Thrombin/metabolism , Thromboplastin/immunology , Thromboplastin/metabolism , Thrombosis/blood , Thrombosis/immunology , Thrombosis/virology
8.
Clin Appl Thromb Hemost ; 27: 10760296211040110, 2021.
Article in English | MEDLINE | ID: covidwho-1430348

ABSTRACT

Since the outbreak of Covid-19 in December, 2019, scientists worldwide have been committed to developing COVID-19 vaccines. Only when most people have immunity to SARS-CoV-2, COVID-19 can reduce even wholly overcome. So far, nine kinds of COVID-19 vaccines have passed the phase III clinical trials and have approved for use. At the same time, adverse reactions after COVID-19 vaccination have also reported. This paper focuses on the adverse effects of thrombosis and thrombocytopenia caused by the COVID-19 vaccine, especially the adenovirus-vector vaccine from AstraZeneca and Pfizer, and discusses its mechanism and possible countermeasures.


Subject(s)
Adenoviridae/genetics , COVID-19 Vaccines/adverse effects , Genetic Vectors , Thrombocytopenia/chemically induced , Thrombosis/chemically induced , Vaccination/adverse effects , Antibodies/blood , COVID-19 Vaccines/genetics , COVID-19 Vaccines/immunology , Humans , Platelet Factor 4/immunology , Risk Assessment , Risk Factors , Thrombocytopenia/blood , Thrombocytopenia/immunology , Thrombosis/blood , Thrombosis/immunology
9.
Int J Mol Sci ; 22(18)2021 Sep 16.
Article in English | MEDLINE | ID: covidwho-1409707

ABSTRACT

Global data correlate severe vitamin D deficiency with COVID-19-associated coagulopathy, further suggesting the presence of a hypercoagulable state in severe COVID-19 patients, which could promote thrombosis in the lungs and in other organs. The feedback loop between COVID-19-associated coagulopathy and vitamin D also involves platelets (PLTs), since vitamin D deficiency stimulates PLT activation and aggregation and increases fibrinolysis and thrombosis. Vitamin D and PLTs share and play specific roles not only in coagulation and thrombosis but also during inflammation, endothelial dysfunction, and immune response. Additionally, another 'fil rouge' between vitamin D and PLTs is represented by their role in mineral metabolism and bone health, since vitamin D deficiency, low PLT count, and altered PLT-related parameters are linked to abnormal bone remodeling in certain pathological conditions, such as osteoporosis (OP). Hence, it is possible to speculate that severe COVID-19 patients are characterized by the presence of several predisposing factors to bone fragility and OP that may be monitored to avoid potential complications. Here, we hypothesize different pervasive actions of vitamin D and PLT association in COVID-19, also allowing for potential preliminary information on bone health status during COVID-19 infection.


Subject(s)
Blood Platelets/immunology , COVID-19/complications , Osteoporosis/immunology , Thrombosis/immunology , Vitamin D Deficiency/immunology , Vitamin D/metabolism , Blood Platelets/metabolism , Bone Remodeling/immunology , COVID-19/blood , COVID-19/diagnosis , COVID-19/immunology , Feedback, Physiological , Humans , Osteoporosis/blood , Platelet Activation/immunology , Platelet Count , SARS-CoV-2/immunology , Severity of Illness Index , Thrombosis/blood , Vitamin D/blood , Vitamin D Deficiency/blood , Vitamin D Deficiency/complications
10.
Nature ; 599(7884): 283-289, 2021 11.
Article in English | MEDLINE | ID: covidwho-1404888

ABSTRACT

Derailed cytokine and immune cell networks account for the organ damage and the clinical severity of COVID-19 (refs. 1-4). Here we show that SARS-CoV-2, like other viruses, evokes cellular senescence as a primary stress response in infected cells. Virus-induced senescence (VIS) is indistinguishable from other forms of cellular senescence and is accompanied by a senescence-associated secretory phenotype (SASP), which comprises pro-inflammatory cytokines, extracellular-matrix-active factors and pro-coagulatory mediators5-7. Patients with COVID-19 displayed markers of senescence in their airway mucosa in situ and increased serum levels of SASP factors. In vitro assays demonstrated macrophage activation with SASP-reminiscent secretion, complement lysis and SASP-amplifying secondary senescence of endothelial cells, which mirrored hallmark features of COVID-19 such as macrophage and neutrophil infiltration, endothelial damage and widespread thrombosis in affected lung tissue1,8,9. Moreover, supernatant from VIS cells, including SARS-CoV-2-induced senescence, induced neutrophil extracellular trap formation and activation of platelets and the clotting cascade. Senolytics such as navitoclax and a combination of dasatinib plus quercetin selectively eliminated VIS cells, mitigated COVID-19-reminiscent lung disease and reduced inflammation in SARS-CoV-2-infected hamsters and mice. Our findings mark VIS as a pathogenic trigger of COVID-19-related cytokine escalation and organ damage, and suggest that senolytic targeting of virus-infected cells is a treatment option against SARS-CoV-2 and perhaps other viral infections.


Subject(s)
COVID-19/drug therapy , COVID-19/pathology , COVID-19/virology , Cellular Senescence/drug effects , Molecular Targeted Therapy , SARS-CoV-2/pathogenicity , Aniline Compounds/pharmacology , Aniline Compounds/therapeutic use , Animals , COVID-19/complications , Cell Line , Cricetinae , Dasatinib/pharmacology , Dasatinib/therapeutic use , Disease Models, Animal , Female , Humans , Male , Mice , Quercetin/pharmacology , Quercetin/therapeutic use , SARS-CoV-2/drug effects , Sulfonamides/pharmacology , Sulfonamides/therapeutic use , Thrombosis/complications , Thrombosis/immunology , Thrombosis/metabolism
11.
Front Immunol ; 12: 716361, 2021.
Article in English | MEDLINE | ID: covidwho-1399137

ABSTRACT

Background: COVID-19 pathology is associated with exuberant inflammation, vascular damage, and activation of coagulation. In addition, complement activation has been described and is linked to disease pathology. However, few studies have been conducted in cancer patients. Objective: This study examined complement activation in response to COVID-19 in the setting of cancer associated thromboinflammation. Methods: Markers of complement activation (C3a, C5a, sC5b-9) and complement inhibitors (Factor H, C1-Inhibitor) were evaluated in plasma of cancer patients with (n=43) and without (n=43) COVID-19 and stratified based on elevated plasma D-dimer levels (>1.0 µg/ml FEU). Markers of vascular endothelial cell dysfunction and platelet activation (ICAM-1, thrombomodulin, P-selectin) as well as systemic inflammation (pentraxin-3, serum amyloid A, soluble urokinase plasminogen activator receptor) were analyzed to further evaluate the inflammatory response. Results: Increases in circulating markers of endothelial cell dysfunction, platelet activation, and systemic inflammation were noted in cancer patients with COVID-19. In contrast, complement activation increased in cancer patients with COVID-19 and elevated D-dimers. This was accompanied by decreased C1-Inhibitor levels in patients with D-dimers > 5 ug/ml FEU. Conclusion: Complement activation in cancer patients with COVID-19 is significantly increased in the setting of thromboinflammation. These findings support a link between coagulation and complement cascades in the setting of inflammation.


Subject(s)
COVID-19/immunology , Complement Activation/immunology , Inflammation/immunology , Neoplasms/immunology , SARS-CoV-2/immunology , Thrombosis/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Biomarkers/blood , COVID-19/blood , COVID-19/virology , Complement Inactivating Agents/blood , Female , Fibrin Fibrinogen Degradation Products/metabolism , Humans , Inflammation/blood , Male , Middle Aged , Neoplasms/blood , Platelet Activation/immunology , Retrospective Studies , SARS-CoV-2/physiology , Thrombosis/blood , Young Adult
12.
J Autoimmun ; 121: 102662, 2021 07.
Article in English | MEDLINE | ID: covidwho-1385817

ABSTRACT

Herein, we consider venous immunothrombotic mechanisms in SARS-CoV-2 infection and anti-SARS-CoV-2 DNA vaccination. Primary SARS-CoV-2 infection with systemic viral RNA release (RNAaemia) contributes to innate immune coagulation cascade activation, with both pulmonary and systemic immunothrombosis - including venous territory strokes. However, anti-SARS-CoV-2 adenoviral-vectored-DNA vaccines -initially shown for the ChAdOx1 vaccine-may rarely exhibit autoimmunity with autoantibodies to Platelet Factor-4 (PF4) that is termed Vaccine-Induced Thrombotic Thrombocytopenia (VITT), an entity pathophysiologically similar to Heparin-Induced Thrombocytopenia (HIT). The PF4 autoantigen is a polyanion molecule capable of independent interactions with negatively charged bacterial cellular wall, heparin and DNA molecules, thus linking intravascular innate immunity to both bacterial cell walls and pathogen-derived DNA. Crucially, negatively charged extracellular DNA is a powerful adjuvant that can break tolerance to positively charged nuclear histone proteins in many experimental autoimmunity settings, including SLE and scleroderma. Analogous to DNA-histone interactons, positively charged PF4-DNA complexes stimulate strong interferon responses via Toll-Like Receptor (TLR) 9 engagement. A chain of events following intramuscular adenoviral-vectored-DNA vaccine inoculation including microvascular damage; microbleeding and platelet activation with PF4 release, adenovirus cargo dispersement with DNA-PF4 engagement may rarely break immune tolerance, leading to rare PF4-directed autoimmunity. The VITT cavernous sinus cerebral and intestinal venous territory immunothrombosis proclivity may pertain to venous drainage of shared microbiotal-rich areas of the nose and in intestines that initiates local endovascular venous immunity by PF4/microbiotal engagement with PF4 autoantibody driven immunothrombosis reminiscent of HIT. According to the proposed model, any adenovirus-vectored-DNA vaccine could drive autoimmune VITT in susceptible individuals and alternative mechanism based on molecular mimicry, vaccine protein contaminants, adenovirus vector proteins, EDTA buffers or immunity against the viral spike protein are secondary factors. Hence, electrochemical DNA-PF4 interactions and PF4-heparin interactions, but at different locations, represent the common denominator in HIT and VITT related autoimmune-mediated thrombosis.


Subject(s)
Autoantibodies/immunology , COVID-19/immunology , Purpura, Thrombocytopenic, Idiopathic/immunology , SARS-CoV-2/immunology , Thrombosis/immunology , Vaccines/adverse effects , COVID-19/pathology , COVID-19/prevention & control , Humans , Platelet Activation/immunology , Platelet Factor 4/immunology , Purpura, Thrombocytopenic, Idiopathic/chemically induced , Purpura, Thrombocytopenic, Idiopathic/pathology , Thrombosis/chemically induced , Thrombosis/pathology , Vaccines/immunology
13.
J Leukoc Biol ; 109(1): 35-47, 2021 01.
Article in English | MEDLINE | ID: covidwho-1372745

ABSTRACT

The SARS-CoV-2 pandemic has led to hundreds of thousands of deaths and billions of dollars in economic damage. The immune response elicited from this virus is poorly understood. An alarming number of cases have arisen where COVID-19 patients develop complications on top of the symptoms already associated with SARS, such as thrombosis, injuries of vascular system, kidney, and liver, as well as Kawasaki disease. In this review, a bioinformatics approach was used to elucidate the immune response triggered by SARS-CoV-2 infection in primary human lung epithelial and transformed human lung alveolar. Additionally, examined the potential mechanism behind several complications that have been associated with COVID-19 and determined that a specific cytokine storm is leading to excessive neutrophil recruitment. These neutrophils are directly leading to thrombosis, organ damage, and complement activation via neutrophil extracellular trap release.


Subject(s)
COVID-19/immunology , SARS-CoV-2/immunology , Signal Transduction/immunology , Thrombosis/immunology , Vascular System Injuries/immunology , COVID-19/pathology , Cytokines/immunology , Humans , Mucocutaneous Lymph Node Syndrome/immunology , Mucocutaneous Lymph Node Syndrome/pathology , Mucocutaneous Lymph Node Syndrome/virology , Pulmonary Alveoli/immunology , Pulmonary Alveoli/pathology , Pulmonary Alveoli/virology , Thrombosis/pathology , Thrombosis/virology , Vascular System Injuries/pathology , Vascular System Injuries/virology
15.
Front Immunol ; 12: 700184, 2021.
Article in English | MEDLINE | ID: covidwho-1365542

ABSTRACT

Coronavirus disease 2019 (COVID-19), which has high incidence rates with rapid rate of transmission, is a pandemic that spread across the world, resulting in more than 3,000,000 deaths globally. Currently, several drugs have been used for the clinical treatment of COVID-19, such as antivirals (radecivir, baritinib), monoclonal antibodies (tocilizumab), and glucocorticoids (dexamethasone). Accumulating evidence indicates that long noncoding RNAs (lncRNAs) are essential regulators of virus infections and antiviral immune responses including biological processes that are involved in the regulation of COVID-19 and subsequent disease states. Upon viral infections, cellular lncRNAs directly regulate viral genes and influence viral replication and pathology through virus-mediated changes in the host transcriptome. Additionally, several host lncRNAs could help the occurrence of viral immune escape by inhibiting type I interferons (IFN-1), while others could up-regulate IFN-1 production to play an antiviral role. Consequently, understanding the expression and function of lncRNAs during severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection will provide insights into the development of lncRNA-based methods. In this review, we summarized the current findings of lncRNAs in the regulation of the strong inflammatory response, immune dysfunction and thrombosis induced by SARS-CoV-2 infection, discussed the underlying mechanisms, and highlighted the therapeutic challenges of COVID-19 treatment and its future research directions.


Subject(s)
COVID-19/immunology , Host Microbial Interactions/genetics , Immunity, Innate/genetics , RNA, Long Noncoding/metabolism , Thrombosis/immunology , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Biomarkers/analysis , COVID-19/complications , COVID-19/drug therapy , COVID-19/genetics , COVID-19 Testing/methods , Cytokines/genetics , Cytokines/metabolism , Gene Expression Regulation, Viral/drug effects , Gene Expression Regulation, Viral/immunology , Host Microbial Interactions/drug effects , Host Microbial Interactions/immunology , Humans , Immune Evasion/genetics , Pandemics/prevention & control , RNA, Long Noncoding/analysis , RNA, Long Noncoding/antagonists & inhibitors , SARS-CoV-2/drug effects , SARS-CoV-2/genetics , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Signal Transduction/genetics , Signal Transduction/immunology , Thrombosis/genetics , Thrombosis/virology , Virus Replication/drug effects , Virus Replication/genetics , Virus Replication/immunology
16.
Nature ; 596(7873): 565-569, 2021 08.
Article in English | MEDLINE | ID: covidwho-1356565

ABSTRACT

Vaccine-induced immune thrombotic thrombocytopaenia (VITT) is a rare adverse effect of COVID-19 adenoviral vector vaccines1-3. VITT resembles heparin-induced thrombocytopaenia (HIT) in that it is associated with platelet-activating antibodies against platelet factor 4 (PF4)4; however, patients with VITT develop thrombocytopaenia and thrombosis without exposure to heparin. Here we sought to determine the binding site on PF4 of antibodies from patients with VITT. Using alanine-scanning mutagenesis5, we found that the binding of anti-PF4 antibodies from patients with VITT (n = 5) was restricted to eight surface amino acids on PF4, all of which were located within the heparin-binding site, and that the binding was inhibited by heparin. By contrast, antibodies from patients with HIT (n = 10) bound to amino acids that corresponded to two different sites on PF4. Biolayer interferometry experiments also revealed that VITT anti-PF4 antibodies had a stronger binding response to PF4 and PF4-heparin complexes than did HIT anti-PF4 antibodies, albeit with similar dissociation rates. Our data indicate that VITT antibodies can mimic the effect of heparin by binding to a similar site on PF4; this allows PF4 tetramers to cluster and form immune complexes, which in turn causes Fcγ receptor IIa (FcγRIIa; also known as CD32a)-dependent platelet activation. These results provide an explanation for VITT-antibody-induced platelet activation that could contribute to thrombosis.


Subject(s)
COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/immunology , Epitopes, B-Lymphocyte/immunology , Thrombocytopenia/chemically induced , Thrombocytopenia/immunology , Thrombosis/chemically induced , Thrombosis/immunology , Adult , Aged , Amino Acid Sequence , Antibodies/immunology , Binding Sites, Antibody , Female , Heparin/chemistry , Heparin/immunology , Heparin/metabolism , Humans , Kinetics , Male , Middle Aged , Models, Molecular , Platelet Activation , Platelet Factor 4/immunology , Receptors, IgG/immunology
17.
Blood ; 138(4): 350-353, 2021 07 29.
Article in English | MEDLINE | ID: covidwho-1331923

ABSTRACT

We report 5 cases of prothrombotic immune thrombocytopenia after exposure to the ChAdOx1 vaccine (AZD1222, Vaxzevria) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Patients presented 5 to 11 days after first vaccination. The spectrum of clinical manifestations included cerebral venous sinus thrombosis, splanchnic vein thrombosis, arterial cerebral thromboembolism, and thrombotic microangiopathy. All patients had thrombocytopenia and markedly elevated D-dimer. Autoantibodies against platelet factor 4 (PF4) were detected in all patients, although they had never been exposed to heparin. Immunoglobulin from patient sera bound to healthy donor platelets in an AZD1222-dependent manner, suppressed by heparin. Aggregation of healthy donor platelets by patient sera was demonstrated in the presence of buffer or AZD1222 and was also suppressed by heparin. Anticoagulation alone or in combination with eculizumab or intravenous immunoglobulin (IVIG) resolved the pathology in 3 patients. Two patients had thromboembolic events despite anticoagulation at a time when platelets were increasing after IVIG. In summary, an unexpected autoimmune prothrombotic disorder is described after vaccination with AZD1222. It is characterized by thrombocytopenia and anti-PF4 antibodies binding to platelets in AZD1222-dependent manner. Initial clinical experience suggests a risk of unusual and severe thromboembolic events.


Subject(s)
COVID-19 Vaccines/adverse effects , COVID-19/prevention & control , Purpura, Thrombocytopenic, Idiopathic/etiology , Thrombosis/etiology , Adult , Aged , Autoantibodies/immunology , COVID-19/immunology , COVID-19 Vaccines/immunology , COVID-19 Vaccines/therapeutic use , Cohort Studies , Female , Humans , Male , Middle Aged , Platelet Factor 4/immunology , Purpura, Thrombocytopenic, Idiopathic/immunology , SARS-CoV-2/immunology , Thrombosis/immunology
18.
Medicine (Baltimore) ; 100(20): e25456, 2021 May 21.
Article in English | MEDLINE | ID: covidwho-1324829

ABSTRACT

INTRODUCTION: Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired, life-threatening hemopoietic stem cell disorder characterized by the triad of hemolytic anemia, thrombosis, and impaired bone marrow function. Evidence suggests that severe outcomes in COVID19 infection are attributed to the excessive activation of the complement cascade leading to acute lung injury and associated is with an increased prothrombotic state. PATIENT CONCERNS: A 27-year-old Caucasian man with PNH presented to the Emergency Department of our hospital with acute onset shortness of breath, cough and blood in urine. DIAGNOSIS: The patient was diagnosed with acute hemolytic exacerbation of PNH complicated with moderate COVID19 pneumonia. OUTCOMES: The patient was initiated with an anticoagulant unfractionated heparin, dexamethasone, and cefuroxime injection. His symptoms quickly resolved, and he was discharged after 5 days. CONCLUSION: The complement system activation is a critical component in the sequalae of COVID19 infection. Evidence suggests that severe outcomes in COVID19 infection are attributed to the excessive activation of the complement cascade leading to acute lung injury and associated is with an increased prothrombotic state. Notably, C5a concentration was noted to be higher in patients with COVID19 infection. The use of complement inhibitors to attenuate immune mediated damage in COVID19 nevertheless represents a very interesting theoretical approach. However, careful consideration as to which patients may benefit will be required and the outcome of clinical trials needed.


Subject(s)
Anticoagulants/administration & dosage , COVID-19/drug therapy , Complement Inactivating Agents/administration & dosage , Hemoglobinuria, Paroxysmal/complications , Thrombosis/prevention & control , Adult , COVID-19/diagnosis , COVID-19/immunology , COVID-19/virology , COVID-19 Serological Testing , Complement Activation/drug effects , Hemoglobinuria, Paroxysmal/blood , Hemoglobinuria, Paroxysmal/drug therapy , Hemoglobinuria, Paroxysmal/immunology , Humans , Male , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , Symptom Flare Up , Thrombosis/immunology , Treatment Outcome
19.
Biomolecules ; 11(7)2021 07 13.
Article in English | MEDLINE | ID: covidwho-1308294

ABSTRACT

Two adenovirus-based vaccines, ChAdOx1 nCoV-19 and Ad26.COV2.S, and two mRNA-based vaccines, BNT162b2 and mRNA.1273, have been approved by the European Medicines Agency (EMA), and are invaluable in preventing and reducing the incidence of coronavirus disease-2019 (COVID-19). Recent reports have pointed to thrombosis with associated thrombocytopenia as an adverse effect occurring at a low frequency in some individuals after vaccination. The causes of such events may be related to SARS-CoV-2 spike protein interactions with different C-type lectin receptors, heparan sulfate proteoglycans (HSPGs) and the CD147 receptor, or to different soluble splice variants of the spike protein, adenovirus vector interactions with the CD46 receptor or platelet factor 4 antibodies. Similar findings have been reported for several viral diseases after vaccine administration. In addition, immunological mechanisms elicited by viral vectors related to cellular delivery could play a relevant role in individuals with certain genetic backgrounds. Although rare, the potential COVID-19 vaccine-induced immune thrombotic thrombocytopenia (VITT) requires immediate validation, especially in risk groups, such as the elderly, chronic smokers, and individuals with pre-existing incidences of thrombocytopenia; and if necessary, a reformulation of existing vaccines.


Subject(s)
COVID-19 Vaccines/adverse effects , COVID-19/prevention & control , Thrombosis/etiology , COVID-19/immunology , Humans , Risk Factors , SARS-CoV-2/immunology , Smokers , Spike Glycoprotein, Coronavirus/immunology , Thrombocytopenia/etiology , Thrombocytopenia/immunology , Thrombosis/immunology , Vaccination/adverse effects
20.
Curr Rheumatol Rep ; 23(8): 65, 2021 07 03.
Article in English | MEDLINE | ID: covidwho-1293441

ABSTRACT

PURPOSE OF REVIEW: COVID-19 patients have a procoagulant state with a high prevalence of thrombotic events. The hypothesis of an involvement of antiphospholipid antibodies (aPL) has been suggested by several reports. Here, we reviewed 48 studies investigating aPL in COVID-19 patients. RECENT FINDINGS: Prevalence of Lupus Anticoagulant (LA) ranged from 35% to 92% in ICU patients. Anti-cardiolipin (aCL) IgG and IgM were found in up to 52% and up to 40% of patients respectively. Anti-ß2-glycoprotein I (aß2-GPI) IgG and IgM were found in up to 39% and up to 34% of patients respectively. Between 1% and 12% of patients had a triple positive aPL profile. There was a high prevalence of aß2-GPI and aCL IgA isotype. Two cohort studies found few persistent LA but more persistent solid phase assay aPL over time. aPL determination and their potential role is a real challenge for the treatment of this disease.


Subject(s)
Antibodies, Antiphospholipid/immunology , COVID-19/immunology , Thrombosis/immunology , Antibodies, Anticardiolipin/immunology , C-Reactive Protein/immunology , COVID-19/blood , COVID-19/complications , Fibrin Fibrinogen Degradation Products/metabolism , Fibrinogen/metabolism , Humans , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Lupus Coagulation Inhibitor/immunology , SARS-CoV-2 , Severity of Illness Index , Thrombosis/blood , Thrombosis/etiology , beta 2-Glycoprotein I/immunology
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