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1.
Clin Immunol ; 238: 109016, 2022 05.
Article in English | MEDLINE | ID: covidwho-1797060

ABSTRACT

Aiming to reduce mortality in COVID-19 with severe respiratory failure we administered a combined rescue treatment (COMBI) on top of standard-of-care (SOC: dexamethasone/heparin) consisted of inhaled DNase to dissolve thrombogenic neutrophil extracellular traps, plus agents against cytokine-mediated hyperinflammation, namely anti-IL-6-receptor tocilizumab and JAK1/2 inhibitor baricitinib. Patients with PaO2/FiO2 < 100 mmHg were analysed. COMBI group (n = 22) was compared with similar groups that had received SOC alone (n = 26) or SOC plus monotherapy with either IL-1-receptor antagonist anakinra (n = 19) or tocilizumab (n = 11). COMBI was significantly associated with lower in-hospital mortality and intubation rate, shorter duration of hospitalization, and prolonged overall survival after a median follow-up of 110 days. In vitro, COVID-19 plasma induced tissue factor/thrombin pathway in primary lung fibroblasts. This effect was inhibited by the immunomodulatory agents of COMBI providing a mechanistic explanation for the clinical observations. These results support the conduct of randomized trials using combined immunomodulation in COVID-19 to target multiple interconnected pathways of immunothrombosis.


Subject(s)
Antibodies, Monoclonal, Humanized , COVID-19 , Deoxyribonucleases , Respiratory Insufficiency , Antibodies, Monoclonal, Humanized/therapeutic use , Azetidines/therapeutic use , COVID-19/drug therapy , Deoxyribonucleases/therapeutic use , Humans , Purines/therapeutic use , Pyrazoles/therapeutic use , Respiratory Insufficiency/drug therapy , Respiratory Insufficiency/virology , SARS-CoV-2 , Sulfonamides/therapeutic use , Treatment Outcome
2.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-330140

ABSTRACT

COVID-19-related severe respiratory failure (SRF) leads to mechanical ventilation increasing the in-hospital mortality substantially. Abundancy of lung fibroblasts (LFs) in injured lung tissue has been associated with the progression of respiratory failure in COVID-19. Aiming to reduce mortality in patients with SRF (PaO2/FiO2<100 mmHg) and considering the multi-mechanistic nature of severe COVID-19 pathogenesis, we applied a combined rescue treatment (COMBI) on top of standard-of-care (SOC: dexamethasone and heparin) comprised inhaled DNase to dissolve thrombogenic neutrophil extracellular traps, plus agents against cytokine-mediated hyperinflammation, such as anti-IL-6 receptor tocilizumab and selective JAK1/2 inhibitor baricitinib. COMBI (n=22) was compared with SOC (n= 26), and with two previously and consecutively used therapeutic approaches, including either IL-1 receptor antagonist anakinra (ANA, n=19), or tocilizumab (TOCI, n=11), on top of SOC. In parallel, evaluation of immunothrombosis was assessed in vitro in human LFs, treated with the applied therapeutic agents upon stimulation with COVID-19 plasma. COMBI was associated with lower in-hospital mortality (p=0.014) and intubation rate (p=0.013), shorter duration of hospitalization (p=0.019), and prolonged overall survival after a median follow-up of 110+/-4 days (p=0.003). In vitro, COVID-19 plasma markedly induced tissue factor/thrombin pathway in LFs, while this effect was inhibited by the immunomodulatory agents of COMBI providing a mechanistic explanation for the clinical observations. These results suggest the design of randomized trials using combined immunomodulatory therapies in COVID-19-associated SRF targeting multiple interconnected pathways of immunothrombosis.

3.
Germs ; 11(3): 372-380, 2021 Sep.
Article in English | MEDLINE | ID: covidwho-1481258

ABSTRACT

INTRODUCTION: The aim of this study was to assess the clinical performance of different automated immunoassays available in Europe to detect anti-SARS-CoV-2 antibodies; an ELISA assay and a CLIA. The second goal was to estimate the seroprevalence of SARS-CoV-2 antibodies among healthcare workers in Evros area during the first pandemic wave of COVID-19. METHODS: The study included serum samples from 101 patients with confirmed COVID-19 by RT-PCR and 208 negative patients. Furthermore, it included 1036 healthcare workers (HWs) of the Evros Region, Northern Greece. The measurement of anti-SARS-CoV-2 antibodies was performed using the Abbott SARS-CoV-2 IgG and anti-SARS-CoV-2 ELISA IgG assay (Epitope Diagnostics, USA). RESULTS: Of 101 confirmed COVID-19 patients, 82 were hospitalized and 19 were outpatients. Hospitalized patients had higher IgG levels in comparison to outpatients (6.46±2.2 vs. 3.52±1.52, p<0.001). Of 208 non-COVID-19 patients only 1 was positive in both ELISA and CLIA assay. SARS-CoV-2-IgG antibodies were detected in 6 HWs out of 1036 (0.58%) with mean S/CO-value of anti-SARS-CoV-2 IgG 3.12±1.3 (confidence interval 0.95), which was lower than in COVID-19 patients (3.12 vs. 5.9; p=0.016). The clinical evaluation of two immunoassays showed remarkably high true positivity rates in the confirmed COVID-19 patients. Sensitivities obtained with CLIA and ELISA methods were 99.02% vs. 97.09% and specificities 99.52% vs 99.05% respectively. CONCLUSIONS: We found an acceptable accordance between CLIA and ELISA assays in the confirmed COVID-19 patients. In all subjects included in this study in the past medical history, the information that was obtained included details about the presence of autoimmune diseases.

4.
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
5.
Front Immunol ; 12: 719023, 2021.
Article in English | MEDLINE | ID: covidwho-1405410

ABSTRACT

There is strong evidence that COVID-19 pathophysiology is mainly driven by a spatiotemporal immune deregulation. Both its phenotypic heterogeneity, spanning from asymptomatic to severe disease/death, and its associated mortality, are dictated by and linked to maladaptive innate and adaptive immune responses against SARS-CoV-2, the etiologic factor of the disease. Deregulated interferon and cytokine responses, with the contribution of immune and cellular stress-response mediators (like cellular senescence or uncontrolled inflammatory cell death), result in innate and adaptive immune system malfunction, endothelial activation and inflammation (endothelitis), as well as immunothrombosis (with enhanced platelet activation, NET production/release and complement hyper-activation). All these factors play key roles in the development of severe COVID-19. Interestingly, another consequence of this immune deregulation, is the production of autoantibodies and the subsequent development of autoimmune phenomena observed in some COVID-19 patients with severe disease. These new aspects of the disease that are now emerging (like autoimmunity and cellular senescence), could offer us new opportunities in the field of disease prevention and treatment. Simultaneously, lessons already learned from the immunobiology of COVID-19 could offer new insights, not only for this disease, but also for a variety of chronic inflammatory responses observed in autoimmune and (auto)inflammatory diseases.


Subject(s)
COVID-19/immunology , SARS-CoV-2/immunology , Humans
6.
Cell Death Differ ; 28(11): 3125-3139, 2021 11.
Article in English | MEDLINE | ID: covidwho-1241944

ABSTRACT

SARS-CoV-2 infection poses a major threat to the lungs and multiple other organs, occasionally causing death. Until effective vaccines are developed to curb the pandemic, it is paramount to define the mechanisms and develop protective therapies to prevent organ dysfunction in patients with COVID-19. Individuals that develop severe manifestations have signs of dysregulated innate and adaptive immune responses. Emerging evidence implicates neutrophils and the disbalance between neutrophil extracellular trap (NET) formation and degradation plays a central role in the pathophysiology of inflammation, coagulopathy, organ damage, and immunothrombosis that characterize severe cases of COVID-19. Here, we discuss the evidence supporting a role for NETs in COVID-19 manifestations and present putative mechanisms, by which NETs promote tissue injury and immunothrombosis. We present therapeutic strategies, which have been successful in the treatment of immunο-inflammatory disorders and which target dysregulated NET formation or degradation, as potential approaches that may benefit patients with severe COVID-19.


Subject(s)
COVID-19/pathology , Extracellular Traps/metabolism , Neutrophils/immunology , COVID-19/complications , COVID-19/immunology , Citrullination , Complement Activation , Humans , Neutrophils/metabolism , Platelet Activation , SARS-CoV-2/isolation & purification , Severity of Illness Index , Thrombosis/etiology
8.
J Infect Dis ; 223(9): 1544-1554, 2021 05 20.
Article in English | MEDLINE | ID: covidwho-1099601

ABSTRACT

BACKGROUND: Activins are members of the transforming growth factor-ß superfamily implicated in the pathogenesis of several immunoinflammatory disorders. Based on our previous studies demonstrating that overexpression of activin-A in murine lung causes pathology sharing key features of coronavirus disease 2019 (COVID-19), we hypothesized that activins and their natural inhibitor follistatin might be particularly relevant to COVID-19 pathophysiology. METHODS: Activin-A, activin-B, and follistatin were retrospectively analyzed in 574 serum samples from 263 COVID-19 patients hospitalized in 3 independent centers, and compared with demographic, clinical, and laboratory parameters. Optimal scaling with ridge regression was used to screen variables and establish a prediction model. RESULT: The activin/follistatin axis was significantly deregulated during the course of COVID-19, correlated with severity and independently associated with mortality. FACT-CLINYCoD, a scoring system incorporating follistatin, activin-A, activin-B, C-reactive protein, lactate dehydrogenase, intensive care unit admission, neutrophil/lymphocyte ratio, age, comorbidities, and D-dimers, efficiently predicted fatal outcome (area under the curve [AUC], 0.951; 95% confidence interval, .919-.983; P <10-6). Two validation cohorts indicated similar AUC values. CONCLUSIONS: This study demonstrates a link between activin/follistatin axis and COVID-19 mortality and introduces FACT-CLINYCoD, a novel pathophysiology-based tool that allows dynamic prediction of disease outcome, supporting clinical decision making.


Subject(s)
Activins/blood , COVID-19/blood , COVID-19/mortality , Follistatin/blood , SARS-CoV-2 , Aged , Biomarkers , COVID-19/physiopathology , Cohort Studies , Decision Support Techniques , Female , Greece/epidemiology , Hospital Mortality , Humans , Male , Middle Aged , Retrospective Studies
10.
Clin Immunol ; 220: 108598, 2020 11.
Article in English | MEDLINE | ID: covidwho-778645

ABSTRACT

Growing clinical evidence has implicated complement as a pivotal driver of COVID-19 immunopathology. Deregulated complement activation may fuel cytokine-driven hyper-inflammation, thrombotic microangiopathy and NET-driven immunothrombosis, thereby leading to multi-organ failure. Complement therapeutics have gained traction as candidate drugs for countering the detrimental consequences of SARS-CoV-2 infection. Whether blockade of terminal complement effectors (C5, C5a, or C5aR1) may elicit similar outcomes to upstream intervention at the level of C3 remains debated. Here we compare the efficacy of the C5-targeting monoclonal antibody eculizumab with that of the compstatin-based C3-targeted drug candidate AMY-101 in small independent cohorts of severe COVID-19 patients. Our exploratory study indicates that therapeutic complement inhibition abrogates COVID-19 hyper-inflammation. Both C3 and C5 inhibitors elicit a robust anti-inflammatory response, reflected by a steep decline in C-reactive protein and IL-6 levels, marked lung function improvement, and resolution of SARS-CoV-2-associated acute respiratory distress syndrome (ARDS). C3 inhibition afforded broader therapeutic control in COVID-19 patients by attenuating both C3a and sC5b-9 generation and preventing FB consumption. This broader inhibitory profile was associated with a more robust decline of neutrophil counts, attenuated neutrophil extracellular trap (NET) release, faster serum LDH decline, and more prominent lymphocyte recovery. These early clinical results offer important insights into the differential mechanistic basis and underlying biology of C3 and C5 inhibition in COVID-19 and point to a broader pathogenic involvement of C3-mediated pathways in thromboinflammation. They also support the evaluation of these complement-targeting agents as COVID-19 therapeutics in large prospective trials.


Subject(s)
Betacoronavirus/pathogenicity , Complement C3/antagonists & inhibitors , Complement C5/antagonists & inhibitors , Complement Inactivating Agents/therapeutic use , Coronavirus Infections/drug therapy , Immunologic Factors/therapeutic use , Pneumonia, Viral/drug therapy , Respiratory Distress Syndrome/drug therapy , Antibodies, Monoclonal, Humanized/therapeutic use , Biomarkers/blood , C-Reactive Protein/metabolism , COVID-19 , Cohort Studies , Complement Activation/drug effects , Complement C3/genetics , Complement C3/immunology , Complement C5/genetics , Complement C5/immunology , Coronavirus Infections/complications , Coronavirus Infections/immunology , Coronavirus Infections/virology , Extracellular Traps/drug effects , Female , Gene Expression , Humans , Interleukin-6/metabolism , Male , Middle Aged , Neutrophils/drug effects , Neutrophils/immunology , Neutrophils/virology , Pandemics , Peptides, Cyclic/therapeutic use , Pneumonia, Viral/complications , Pneumonia, Viral/immunology , Pneumonia, Viral/virology , Respiratory Distress Syndrome/complications , Respiratory Distress Syndrome/immunology , Respiratory Distress Syndrome/virology , SARS-CoV-2 , Severity of Illness Index
11.
Eur J Rheumatol ; 7(Suppl 2): S110-S116, 2020 Aug.
Article in English | MEDLINE | ID: covidwho-337640

ABSTRACT

Hydroxychloroquine (HCQ) has sparked much interest in the therapeutics of the Coronavirus Disease 2019 (COVID-19) pandemic. Its antiviral properties have been studied for years; regarding the Severe Acute Respiratory Syndrome-Corona Virus-2 (SARS-CoV-2), it has been shown that HCQ may act at multiple levels. These extend from the initial attachment of the virus to the respiratory epithelium to the inhibition of its replication by the alkalinisation of the phagolysosome's microenvironment and the post-translational modification of certain viral proteins. Preliminary clinical evidence from China and France showed significant virological and clinical benefit in HCQ-treated patients, while other studies, mostly including critically ill patients, did not show favorable results. In this review, we critically appraise the existing evidence on HCQ against SARS-CoV-2 with particular emphasis on its protective and therapeutic role. Safety concerns that are relevant to the short-term HCQ use are also discussed. In the context of the rapid evolution of the COVID-19 pandemic that strains the health care systems worldwide and considering limited population-wide testing rates in most of the vulnerable countries, early empiric short-term administration of HCQ in symptomatic individuals, may be a promising, safe and low-cost strategy.

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