Inflammatory and Prothrombotic Biomarkers Associated With the Severity of COVID-19 Infection

The fatal contribution of serine protease-related genetic variants to COVID-19 outcomes

Introduction

Serine proteases play a critical role during SARS-CoV-2 infection. Therefore, polymorphisms of transmembrane protease serine 2 (TMPRSS2) and serpine family E member 1 (SERPINE1) could help to elucidate the contribution of variability to COVID-19 outcomes.

Methods

To evaluate the genetic variants of the genes previously associated with COVID-19 outcomes, we performed a cross-sectional study in which 1536 SARS-CoV-2-positive participants were enrolled. TMPRSS2 (rs2070788, rs75603675, rs12329760) and SERPINE1 (rs2227631, rs2227667, rs2070682, rs2227692) were genotyped using the Open Array Platform. The association of polymorphisms with disease outcomes was determined by logistic regression analysis adjusted for covariates (age, sex, hypertension, type 2 diabetes, and obesity).

Results

According to our codominant model, the GA genotype of rs2227667 (OR=0.55; 95% CI = 0.36-0.84; p=0.006) and the AG genotype of rs2227667 (OR=0.59; 95% CI = 0.38-0.91; p=0.02) of SERPINE1 played a protective role against disease. However, the rs2227692 T allele and TT genotype SERPINE1 (OR=1.45; 95% CI = 1.11-1.91; p=0.006; OR=2.08; 95% CI = 1.22-3.57; p=0.007; respectively) were associated with a decreased risk of death. Similarly, the rs75603675 AA genotype TMPRSS2 had an OR of 1.97 (95% CI = 1.07-3.6; p=0.03) for deceased patients. Finally, the rs2227692 T allele SERPINE1 was associated with increased D-dimer levels (OR=1.24; 95% CI = 1.03-1.48; p=0.02).

Discussion

Our data suggest that the rs75603675 TMPRSS2 and rs2227692 SERPINE1 polymorphisms are associated with a poor outcome. Additionally, rs2227692 SERPINE1 could participate in hypercoagulable conditions in critical COVID-19 patients, and this genetic variant could contribute to the identification of new pharmacological targets and treatment strategies to block the inhibition of TMPRSS2 entry into SARS-CoV-2.

Thrombotic risk assessed by PAI-1 in patients with COVID-19: The influence of hyperglycemia and diabetes mellitus

OBJECTIVE

To assess thrombotic risk with PAI-1 levels in patients with COVID-19, to evaluate PAI-1 differences between hyperglycemic and/or Type 2 Diabetes Mellitus (T2DM) versus non-hyperglycemic patients, and to analyze the association of plasminogen activator inhibitor-1 (PAI-1) with hyperglycemia and T2DM.

METHODS

A cross-sectional study carried out in 181 patients hospitalized for COVID-19. Two groups were formed: the patients with hyperglycemia at admission and/or previously diagnosed T2DM group and the non-hyperglycemic group. Fibrinolysis was assessed by measuring PAI-1 levels by ELISA.

RESULTS

The mean age was 59.4±16.1 years; 55.8% were male 54.1% of patients presented obesity, 38.1% had pre-existing T2DM and 50.8% had admission hyperglycemia and/or pre-existing T2DM. The patients with admission hyperglycemia and/or preexisting T2DM had higher PAI-1 compared with non-hyperglycemic patients [197.5 (128.8-315.9) vs 158.1 (113.4-201.4) ng/mL; p=0.031]. The glucose levels showed a positive correlation with PAI-1 levels (r=0.284, p=0.041). A multivariate logistic regression analysis showed association of PAI-1 level and hyperglycemia and pre-existing T2DM with severity of COVID-19.

CONCLUSION

Patients hospitalized for COVID-19 infection with preexisting T2DM or hyperglycemia detected during their hospitalization presented a greater increase in PAI-1 levels, which suggests that hyperglycemia contributes directly to the hypercoagulable state and probably a worse outcome from the patients.

The Correlation Between sP-Selectin and Platelet Count in COVID-19 Patients in Referral Hospital, West Java Indonesia

Introduction

sP-selectin is a glycoprotein located in α granules of platelet and endothelial's Weibel Palade body, as expression to platelet activation and endothelial cell stimulation by SARS-CoV-2 binding with ACE2 receptor. Consumptive thrombocytopenia is also related to platelet activation. Elevation of sP-selectin and thrombocytopenia are related to COVID-19 complication and often correlated with severity of COVID-19.

Purpose

Assess the correlation between sP-selectin and platelet in COVID-19 patients at intensive care and non-intensive care.

Patients and Methods

The study population was hospitalized COVID-19 patients confirmed by Real-Time PCR that underwent platelet examination within 48 hours upon admission, divided into intensive care and non-intensive care group. sP-selectin examination using ELISA methods. Platelet cell count and sP-selectin divided based on normal reference range.

Results

The subjects consist of 24 were in intensive care, 25 were in non-intensive care group. A 66.7% of subject in intensive care group has an elevation in sP-selection (>44.0 ng/mL). Thrombocytopenia was significantly correlated with intensive group (r =-0.32, p<0.05). The combination of platelet count <150.000/mm3 and sP-selectin >44.0ng/mL was not correlated with the intensive and non-intensive group. Platelet and sP-selectin were not correlated with each other.

Conclusion

Thrombocytopenia is able to induce the expression of sP-selectin.

Crizanlizumab in sickle cell disease

Vaso-occlusion in sickle cell disease (SCD) leads to a myriad of manifestations driving morbidity and mortality in patients with SCD. Increased leucocyte adhesion and P-selectin expression on platelets and endothelial cells is an inciting event that leads to obstruction of microcirculation by adhesion with rigid sickled red blood cells. Crizanlizumab is a first-in-class monoclonal antibody that inhibits P-selectin and has been shown to decrease the frequency of vaso-occlusive pain crises in patients with SCD in clinical trials. The role of crizanlizumab in other manifestations of SCD still needs further investigation.

SARS-CoV-2 infection of human pluripotent stem cell-derived vascular cells reveals smooth muscle cells as key mediators of vascular pathology during infection

Although respiratory symptoms are the most prevalent disease manifestation of infection by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), nearly 20% of hospitalized patients are at risk for thromboembolic events 1 . This prothrombotic state is considered a key factor in the increased risk of stroke, which has been observed clinically during both acute infection and long after symptoms have cleared 2 . Here we developed a model of SARS-CoV-2 infection using human-induced pluripotent stem cell-derived endothelial cells, pericytes, and smooth muscle cells to recapitulate the vascular pathology associated with SARS-CoV-2 exposure. Our results demonstrate that perivascular cells, particularly smooth muscle cells (SMCs), are a specifically susceptible vascular target for SARS-CoV-2 infection. Utilizing RNA sequencing, we characterized the transcriptomic changes accompanying SARS-CoV-2 infection of SMCs, and endothelial cells (ECs). We observed that infected human SMCs shift to a pro-inflammatory state and increase the expression of key mediators of the coagulation cascade. Further, we showed human ECs exposed to the secretome of infected SMCs produce hemostatic factors that can contribute to vascular dysfunction, despite not being susceptible to direct infection. The findings here recapitulate observations from patient sera in human COVID-19 patients and provide mechanistic insight into the unique vascular implications of SARS-CoV-2 infection at a cellular level.

PAI-1 regulates AT2-mediated re-alveolarization and ion permeability

BACKGROUND

Acute lung injury is characterized by overwhelmingly elevated PAI-1 in both lung edema fluid and the circulating system. The role of increased PAI-1, encoded by Serpine1 gene, in the regeneration of injured lung epithelium has not been understood completely. This study aimed to investigate the role of Serpine1 in the regulation of alveolar type 2 epithelial cell (AT2) fate in a humanized mouse line carrying diseased mutants (Serpine1^Tg).

METHODS

Wild-type (wt) and Serpine1^Tg AT2 cells were either cultured as monolayers or 3D alveolospheres. Colony-forming assay and total surface area of organoids were analyzed. AT1 and AT2 cells in organoids were counted by immunohistochemistry and fluorescence-activated cell sorting (FACS). To test the potential effects of elevated PAI-1 on the permeability in the epithelial monolayers, we digitized the biophysical properties of polarized AT2 monolayers grown at the air-liquid interface.

RESULTS

A significant reduction in total AT2 cells harvested in Serpine1^Tg mice was observed compared with wt controls. AT2 cells harvested from Serpine1^Tg mice reduced significantly over the wt controls. Spheroids formed by Serpine1^Tg AT2 cells were lesser than wt control. Similarly, the corresponding surface area, a readout of re-alveolarization of injured epithelium, was markedly reduced in Serpine1^Tg organoids. FACS analysis revealed a significant suppression in the number of AT2 cells, in particular, the CD44⁺ subpopulation, in Serpine1^Tg organoids. A lesser ratio of AT1:AT2 cells in Serpine1^Tg organoids was observed compared with wt cultures. There was a significant increase in transepithelial resistance but not amiloride inhibition.

CONCLUSIONS

Our study suggests elevated PAI-1 in injured lungs downregulates alveolar epithelial regeneration by reducing the AT2 self-renewal, particularly in the CD44⁺ cells.

Biomarkers of endothelial dysfunction are associated with poor outcome in COVID-19 patients: A systematic review and meta-analysis

Numerous studies have linked coronavirus disease 2019 (COVID-19) with endothelial dysfunction and reported elevated levels of endothelial biomarkers in this disease. We conducted a systematic review and meta-analysis of the published evidence in this respect. A systematic literature search of PubMed and Scopus databases was performed to find studies investigating biomarkers of endothelial dysfunction in COVID-19 patients. Pooled standardized mean differences and their 95% confidence intervals were calculated for each biomarker using random effect model. 74 studies with 7668 patients were included. In comparison to patients with good outcome, those with poor outcome had higher levels of von Willebrand factor (vWF) (SMD: 0.83, 95% CI: 0.59-1.07, p < 0.00001), vWF:ADAMTS13 (1.23, (0.77-1.7), p < 0.00001), angiopoietin-2 (Ang-2) (1.06 (0.6-1.51), p < 0.0001), E-selectin (1.09 (0.55-1.63), p < 0.0001), P-selectin (0.59 (0.24-0.94), p = 0.001), syndecan-1 (0.99 (0.6-1.37), p < 0.00001), mid-regional pro-adrenomedullin (MR-proADM) (1.52 (1.35-1.68), p < 0.00001), vascular endothelial growth factor (0.27 (0.02-0.53), p = 0.03), soluble fms-like tyrosine kinase-1 (sFLT-1) (1.93 (0.65-3.21), p = 0.03) and lower levels of ADAMTS13 antigen (-0.69 (-0.9 to -0.47) p < 0.00001) and activity (-0.84 (-1.06 to -0.61) p < 0.0000). Plasminogen activator inhibitor-1 and tissue plasminogen activator levels were not different between the two groups (p < 0.05). There were elevated levels of endothelial dysfunction biomarkers in COVID-19 patients with poor outcome, indicating their possible role in disease severity and prognosis. In particular, MR-proADM, vWF, syndecan-1 and sFLT-1 showed a significant association with poor outcome in these patients.

LC-MS/MS: A sensitive and selective analytical technique to detect COVID-19 protein biomarkers in the early disease stage

INTRODUCTION

The COVID-19 outbreak has put enormous pressure on the scientific community to detect infection rapidly, identify the status of disease severity, and provide an immediate vaccine/drug for the treatment. Relying on immunoassay and a real-time reverse transcription polymerase chain reaction (rRT-PCR) led to many false-negative and false-positive reports. Therefore, detecting biomarkers is an alternative and reliable approach for determining the infection, its severity, and disease progression. Recent advances in liquid chromatography and mass spectrometry (LC-MS/MS) enable the protein biomarkers even at low concentrations, thus facilitating clinicians to monitor the treatment in hospitals.

AREAS COVERED

This review highlights the role of LC-MS/MS in identifying protein biomarkers and discusses the clinically significant protein biomarkers such as Serum amyloid A, Interleukin-6, C-Reactive Protein, Lactate dehydrogenase, D-dimer, cardiac troponin, ferritin, Alanine transaminase, Aspartate transaminase, gelsolin and galectin-3-binding protein in COVID-19, and their analysis by LC-MS/MS in the early stage.

EXPERT OPINION

Clinical doctors monitor significant biomarkers to understand, stratify, and treat patients according to disease severity. Knowledge of clinically significant COVID-19 protein biomarkers is critical not only for COVID-19 caused by the coronavirus but also to prepare us for future pandemics of other diseases in detecting by LC-MS/MS at the early stages.

PAI-1 regulates AT2-mediated re-alveolarization and ion permeability

Background Acute lung injury is characterized by overwhelmingly elevated PAI-1 in both lung edema fluid and the circulating system. The role of increased PAI-1, encoded by Serpine1 gene, in the regeneration of injured lung epithelium has not been understood completely. This study aimed to investigate the role of Serpine1 in the regulation of alveolar type 2 epithelial cell (AT2) fate in a humanized mouse line carrying diseased mutants (Serpine1Tg). Methods Wild type (wt) and Serpine1Tg AT2 cells were either cultured as monolayers or 3D alveolospheres. Colony forming assay and total surface area of organoids were analyzed. AT1 and AT2 cells in organoids were counted by immunohistochemistry and fluorescence-activated cell sorting (FACS). To test the potential effects of elevated PAI-1 on the permeability in the epithelial monolayers, we digitized the biophysical properties of polarized AT2 monolayers grown at the air-liquid interface. Results A significant reduction in total AT2 cells harvested in Serpine1Tg mice was observed compared with wt controls. AT2 cells harvested from Serpine1Tg mice reduced significantly over the wt controls. Spheroids formed by Serpine1Tg AT2 cells were lesser than wt control. Similarly, the corresponding surface area, a readout of realveolarization of injured epithelium, was markedly reduced in Serpine1Tg organoids. FACS analysis revealed a significant suppression in the number of AT2 cells, in particular, the CD44+ subpopulation, in Serpine1Tg organoids. A lesser ratio of AT1:AT2 cells in Serpine1Tg organoids was observed compared with wt cultures. There was a significant increase in transepithelial resistance but not amiloride inhibition. Conclusions Our study suggests elevated PAI-1 in injured lungs downregulates alveolar epithelial regeneration by reducing the AT2 self-renewal, particularly in the CD44+ cells.

Plasminogen activator inhibitor 1 is not a major causative factor for exacerbation in a mouse model of SARS-CoV-2 infection

Coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains a global pandemic. Although several vaccines targeting SARS-CoV-2 spike proteins protect against COVID-19 infection, mutations affecting virus transmissibility and immune evasion potential have reduced their efficacy, leading to the need for a more efficient strategy. Available clinical evidence regarding COVID-19 suggests that endothelial dysfunction with thrombosis is a central pathogenesis of progression to systemic disease, in which overexpression of plasminogen activator inhibitor-1 (PAI-1) may be important. Here we developed a novel peptide vaccine against PAI-1 and evaluated its effect on lipopolysaccharide (LPS)-induced sepsis and SARS-CoV-2 infection in mice. Administration of LPS and mouse-adapted SARS-CoV-2 increased serum PAI-1 levels, although the latter showed smaller levels. In an LPS-induced sepsis model, mice immunized with PAI-1 vaccine showed reduced organ damage and microvascular thrombosis and improved survival compared with vehicle-treated mice. In plasma clot lysis assays, vaccination-induced serum IgG antibodies were fibrinolytic. However, in a SARS-CoV-2 infection model, survival and symptom severity (i.e., body weight reduction) did not differ between vaccine- and vehicle-treated groups. These results indicate that although PAI-1 may promote the severity of sepsis by increasing thrombus formation, it might not be a major contributor to COVID-19 exacerbation.

Blood leukocyte transcriptional modules and differentially expressed genes associated with disease severity and age in COVID-19 patients

Since the molecular mechanisms determining COVID-19 severity are not yet well understood, there is a demand for biomarkers derived from comparative transcriptome analyses of mild and severe cases, combined with patients' clinico-demographic and laboratory data. Here the transcriptomic response of human leukocytes to SARS-CoV-2 infection was investigated by focusing on the differences between mild and severe cases and between age subgroups (younger and older adults). Three transcriptional modules correlated with these traits were functionally characterized, as well as 23 differentially expressed genes (DEGs) associated to disease severity. One module, correlated with severe cases and older patients, had an overrepresentation of genes involved in innate immune response and in neutrophil activation, whereas two other modules, correlated with disease severity and younger patients, harbored genes involved in the innate immune response to viral infections, and in the regulation of this response. This transcriptomic mechanism could be related to the better outcome observed in younger COVID-19 patients. The DEGs, all hyper-expressed in the group of severe cases, were mostly involved in neutrophil activation and in the p53 pathway, therefore related to inflammation and lymphopenia. These biomarkers may be useful for getting a better stratification of risk factors in COVID-19.

Immune, inflammatory and prothrombotic parameters in COVID-19 patients treated with an anti EGFR antibody

SARS-CoV-2 infection causes a range of clinical presentations and induces changes in both innate and adaptive branches of the immune system. Furthermore, direct viral action to the cells of the lung promotes over-expression of the epidermal growth factor receptor (EGFR) which triggers pro-inflammatory response, contributes to coagulopathy and intravascular thrombi as well as lung fibrosis. Based on the role of this signaling pathway in the pathophysiology of the disease, nimotuzumab, an anti-EGFR monoclonal antibody, was used to treat patients with COVID-19. The aim of this study was to determine IL-6 and PAI-1 concentrations and lymphocyte subpopulations profiles in moderately and severely ill COVID-19 patients diagnosed during the B.1.617.2 variant wave in Cuba and included in a phase I/II trial to evaluate the safety and preliminary effect of nimotuzumab in COVID-19 disease. We observed high serum levels of IL-6, elevated plasma concentration of PAI-1, mean values of neutrophils to lymphocytes ratio (NLR) above three and CD4+ lymphopenia in both groups of patients. PAI-1 and IL-6 circulating levels decreased in patients treated with nimotuzumab. More than 95% of patients in which IL-6 decreased or increased slightly, were alive within 14 days after the monoclonal antibody administration. Patients with moderate and severe disease, were no different regarding the studied parameters, addressing the idea that several immune alterations could be present before the infection becomes clinically relevant. These findings suggest that nimotuzumab could be an attractive therapeutic option to interfere with the negative relationship between cytokines and procoagulant mediators in the inflammatory and prothrombotic phases of the disease.

Prognostic value of von Willebrand factor and ADAMTS13 in patients with COVID-19: A systematic review and meta-analysis

Background

Endotheliopathy and coagulopathy appear to be the main causes for critical illness and death in patients with coronavirus disease 2019 (COVID-19). The adhesive ligand von Willebrand factor (VWF) has been involved in immunothrombosis responding to endothelial injury. Here, we reviewed the current literature and performed meta-analyses on the relationship between both VWF and its cleaving protease ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin type 1 motif, member 13) with the prognosis of COVID-19.

Methods

We searched MEDLINE, Cochrane Library, Web of Science, and EMBASE databases from inception to 4 March 2022 for studies analyzing the relationship between VWF-related variables and composite clinical outcomes of patients with COVID-19. The VWF-related variables analyzed included VWF antigen (VWF:Ag), VWF ristocetin cofactor (VWF:Rco), ADAMTS13 activity (ADAMTS13:Ac), the ratio of VWF:Ag to ADAMTS13:Ac, and coagulation factor VIII (FVIII). The unfavorable outcomes were defined as mortality, intensive care unit (ICU) admission, and severe disease course. We used random or fixed effects models to create summary estimates of risk. Risk of bias was assessed based on the principle of the Newcastle-Ottawa Scale.

Results

A total of 3764 patients from 40 studies were included. The estimated pooled means indicated increased plasma levels of VWF:Ag, VWF:Rco, and VWF:Ag/ADAMTS13:Ac ratio, and decreased plasma levels of ADAMTS13:Ac in COVID-19 patients with unfavorable outcomes when compared to those with favorable outcomes (composite outcomes or subgroup analyses of non-survivor versus survivor, ICU versus non-ICU, and severe versus non-severe). In addition, FVIII were higher in COVID-19 patients with unfavorable outcomes. Subgroup analyses indicated that FVIII was higher in patients admitting to ICU, while there was no significant difference between non-survivors and survivors.

Conclusions

The imbalance of the VWF-ADAMTS13 axis (massive quantitative and qualitative increases of VWF with relative deficiency of ADAMTS13) is associated with poor prognosis of patients with COVID-19.

A Vicious Cycle: In Severe and Critically Ill COVID-19 Patients

The coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, is one of the fastest-evolving viral diseases that has instigated a worldwide pandemic. Severe inflammatory syndrome and venous thrombosis are commonly noted in COVID-19 patients with severe and critical illness, contributing to the poor prognosis. Interleukin (IL)-6, a major complex inflammatory cytokine, is an independent factor in predicting the severity of COVID-19 disease in patients. IL-6 and tumor necrosis factor (TNF)-α participate in COVID-19-induced cytokine storm, causing endothelial cell damage and upregulation of plasminogen activator inhibitor-1 (PAI-1) levels. In addition, IL-6 and PAI-1 form a vicious cycle of inflammation and thrombosis, which may contribute to the poor prognosis of patients with severe COVID-19. Targeted inhibition of IL-6 and PAI-1 signal transduction appears to improve treatment outcomes in severely and critically ill COVID-19 patients suffering from cytokine storms and venous thrombosis. Motivated by studies highlighting the relationship between inflammatory cytokines and thrombosis in viral immunology, we provide an overview of the immunothrombosis and immunoinflammation vicious loop between IL-6 and PAI-1. Our goal is that understanding this ferocious circle will benefit critically ill patients with COVID-19 worldwide.

Circulating biomarkers of inflammaging as potential predictors of COVID-19 severe outcomes

The COVID-19 pandemic caused by SARS-CoV-2 infection has been of unprecedented clinical and socio-economic worldwide relevance. The case fatality rate for COVID-19 grows exponentially with age and the presence of comorbidities. In the older patients, COVID-19 manifests predominantly as a systemic disease associated with immunological, inflammatory, and procoagulant responses. Timely diagnosis and risk stratification are crucial steps to define appropriate therapies and reduce mortality, especially in the older patients. Chronically and systemically activated innate immune responses and impaired antiviral responses have been recognized as the results of a progressive remodeling of the immune system during aging, which can be described by the words 'immunosenescence' and 'inflammaging'. These age-related features of the immune system were highlighted in patients affected by COVID-19 with the poorest clinical outcomes, suggesting that the mechanisms underpinning immunosenescence and inflammaging could be relevant for COVID-19 pathogenesis and progression. Increasing evidence suggests that senescent myeloid and endothelial cells are characterized by the acquisition of a senescence-associated pro-inflammatory phenotype (SASP), which is considered as the main culprit of both immunosenescence and inflammaging. Here, we reviewed this evidence and highlighted several circulating biomarkers of inflammaging that could provide additional prognostic information to stratify COVID-19 patients based on the risk of severe outcomes.

Evidence showing lipotoxicity worsens outcomes in covid-19 patients and insights about the underlying mechanisms

We compared three hospitalized patient cohorts and conducted mechanistic studies to determine if lipotoxicity worsens COVID-19. Cohort-1 (n = 30) compared COVID-19 patients dismissed home to those requiring intensive-care unit (ICU) transfer. Cohort-2 (n = 116) compared critically ill ICU patients with and without COVID-19. Cohort-3 (n = 3969) studied hypoalbuminemia and hypocalcemia’s impact on COVID-19 mortality. Patients requiring ICU transfer had higher serum albumin unbound linoleic acid (LA). Unbound fatty acids and LA were elevated in ICU transfers, COVID-19 ICU patients and ICU non-survivors. COVID-19 ICU patients (cohort-2) had greater serum lipase, damage-associated molecular patterns (DAMPs), cytokines, hypocalcemia, hypoalbuminemia, organ failure and thrombotic events. Hypocalcemia and hypoalbuminemia independently associated with COVID-19 mortality in cohort-3. Experimentally, LA reacted with albumin, calcium and induced hypocalcemia, hypoalbuminemia in mice. Endothelial cells took up unbound LA, which depolarized their mitochondria. In mice, unbound LA increased DAMPs, cytokines, causing endothelial injury, organ failure and thrombosis. Therefore, excessive unbound LA in the circulation may worsen COVID-19 outcomes.

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Three cohorts of hospitalized COVID-19 patients with different severities were studied

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Severe COVID-19 increased serum linoleic acid (LA) and unbound fatty acid levels

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Endothelial cell uptake of unbound LA dose-dependently depolarized mitochondria

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Unbound LA increased cytokines, endothelial injury, organ failure and thrombosis

Clinical and Laboratory Profiles of SARS-CoV-2 Delta Variant Compared to Pre-Delta Variants

BACKGROUND

The emergence of SARS-CoV-2 variants of concern has led to significant phenotypical changes in transmissibility, virulence, and public health measures. Our study used clinical data to compare characteristics between a Delta variant wave and a pre-Delta variant wave of hospitalized patients.

METHODS

This single-center retrospective study defined a wave as an increasing number of COVID-19 hospitalizations, which peaked and later decreased. Data from the United States Department of Health and Human Services was used to identify the waves' primary variant. Wave 1 (08/08/20-04/01/21) was characterized by heterogeneous variants, while Wave 2 (06/26/21-10/18/21) was predominantly Delta variant. Descriptive statistics, regression techniques, and machine learning approaches supported the comparisons between waves.

RESULTS

From the cohort(n=1318), Wave 2 patients(n=665) were more likely to be younger, have fewer comorbidities, require more ICU care, and show an inflammatory profile with higher C-reactive protein, lactate dehydrogenase, ferritin, fibrinogen, prothrombin time, activated thromboplastin time, and INR compared to Wave 1. The gradient boosting model showed an area under the ROC curve of 0.854(sensitivity 86.4%;specificity 61.5%;positive predictive value 73.8%; negative predictive value 78.3%).

CONCLUSIONS

Clinical and laboratory characteristics can be used to estimate the COVID-19 variant regardless of genomic testing availability. This finding has implications for variant-driven treatment protocols and further research.

Cytokine profiles in the detection of severe lung involvement in hospitalized patients with COVID-19: The IL-8/IL-32 axis

Coronavirus disease 2019 (COVID-19) is an infectious respiratory disorder caused by a new coronavirus called SARS-CoV-2. The pathophysiology of severe COVID-19 is associated with a “cytokine storm”. IL-32 is a key modulator in the pathogenesis of various clinical conditions and is mostly induced by IL-8. IL-32 modulates important inflammatory pathways (including TNF-α, IL-6 and IL-1b), contributing to the pathogenesis of inflammatory diseases. Il-32 was never evaluated before in COVID-19 patients stratifying as mild-moderate and severe patients. A total of 64 COVID-19 patients, 27 healthy controls were consecutively enrolled in the study. Serum concentrations of biomarkers including IL-1β, IL-10, IFN-γ, TNF-α and IL-6 were quantified by bead-based multiplex analysis and Serum concentration of IL-8 and IL-32 were determined by enzyme-linked immunosorbent assay (ELISA) kits. Interestingly, among the blood parameters, neutrophil and lymphocyte counts were significantly lower in severe COVID-19 patients than in the other, on the contrary, CRP was significantly higher in severe patients than in other groups. The cytokines that best distinguished controls from COVID-19 patients were IL-8 and IL-32, while IL-6 resulted the better variables for discriminate severe group.

The best model performance for severe group was obtained by the combination of IL-32, IL-6, IFN-γ, and CRP serum concentration showing an AUC = 0.83. A cut off of 15 pg/ml of IL-6 greatly discriminate survivor from death patients. New insights related to the cytokine storm in COVID-19 patients, highlighting different severity of disease infection.

Severe Acute Respiratory Syndrome Coronavirus 2 Infection is Associated with Homocysteine Level and Clinical Outcomes in Ischemic Stroke Patients

BACKGROUND: Since its emergence in December 2019 and declared as pandemic in March 2020, the drastic increase in cases of coronavirus disease 2019 (COVID-19) is alarming the importance of disease monitoring in order to prevent further complication, like ischemic stroke. One of the efforts is utilizing biomarker. For instance, elevated homocysteine level, already known risk factor of ischemic stroke, is currently identified in COVID-19 patients. AIM: To assess factor associated with homocysteine level and clinical outcomes of ischemic stroke patients. Methods: A cross-sectional study was conducted at Dr. Zainoel Abidin Hospital di Indonesia between March and August 2021. Ischemic stroke patients who had physical and neurology examinations, SARS-CoV-2 RT-PCR swab, chest x-ray, electrocardiography, head CT-scan and the total homocysteine level were included. To assess the factors associated with homocysteine level and the outcomes of ischemic stroke patients, the independent Student t-test or Anova and chi-squared were used, respectively. RESULTS: We included 62 ischemic stroke patients of which 32 (51.6%) were male and the age ranged between 30 and 80 years. Out of total, 60 patients (96.8%) were survived after the hospital admission. There was a significant association between gender and having COVID-19 with homocysteine level (p=0.012 and p=0.020, respectively). Having COVID-19 was the only variable significantly associated with the outcome of the ischemic stroke patient (p=0.035). CONCLUSION: COVID-19 is associated with homocysteine level and the clinical outcome in ischemic stroke patients. Therefore, SARS-CoV-2 infection in ischemic stroke or vice versa need to be monitored closely in hospital settings.

COVID-19, Vaccines, and Thrombotic Events: A Narrative Review

The coronavirus disease 2019 (COVID-19), a deadly pandemic that has affected millions of people worldwide, is associated with cardiovascular complications, including venous and arterial thromboembolic events. Viral spike proteins, in fact, may promote the release of prothrombotic and inflammatory mediators. Vaccines, coding for the spike protein, are the primary means for preventing COVID-19. However, some unexpected thrombotic events at unusual sites, most frequently located in the cerebral venous sinus but also splanchnic, with associated thrombocytopenia, have emerged in subjects who received adenovirus-based vaccines, especially in fertile women. This clinical entity was soon recognized as a new syndrome, named vaccine-induced immune thrombotic thrombocytopenia, probably caused by cross-reacting anti-platelet factor-4 antibodies activating platelets. For this reason, the regulatory agencies of various countries restricted the use of adenovirus-based vaccines to some age groups. The prevailing opinion of most experts, however, is that the risk of developing COVID-19, including thrombotic complications, clearly outweighs this potential risk. This point-of-view aims at providing a narrative review of epidemiological issues, clinical data, and pathogenetic hypotheses of thrombosis linked to both COVID-19 and its vaccines, helping medical practitioners to offer up-to-date and evidence-based counseling to their often-alarmed patients with acute or chronic cardiovascular thrombotic events.

Use of Radiology, D-Dimer, and Mean Platelet Volume Combination as a Prognostic Marker in Hospitalized Coronavirus Disease-19 Patients

Introduction

The search for biomarkers that could help in predicting disease prognosis in the Coronavirus Disease-2019 (COVID-19) outbreak is still high on the agenda.

Objective

To find out the efficacy of D-dimer and mean platelet volume (MPV) combination as a prognostic marker in hospitalized COVID-19 patients with bilateral infiltration.

Materials and Methods

Study design: Retrospective observational cohort. Patients who were presented to our hospital between March 16, 2020 and June 07, 2020 were reviewed retrospectively. The primary outcome of the study was specified as the need for intensive care, while the secondary outcomes were duration of treatment and hospitalization. Receiver operator curve (ROC) analyzes were carried out to assess the efficacy of D-dimer and MPV parameters as prognostic markers.

Results

Between the mentioned dates, 575 of 1,564 patients were found to be compatible with COVID-19, and the number of patients who were included in the study was 306. The number of patients who developed the need for intensive care was 40 (13.1%). For serum D-dimer levels in assessing the need for intensive care, the area under the curve (AUC) was found to be 0.707 (95% CI: 0.620–0.794). The AUC for MPV was 0.694 (95% CI: 0.585–0.803), when D-dimer was ≥1.0 mg/L. When patients with a D-dimer level of ≥1.0 mg/L were divided into two groups considering the MPV cut-off value as 8.1, the rate of intensive care transport was found to be significantly higher in patients with an MPV of ≥8.1 fL compared to those with an MPV of &lt;8.1 fL (32.6 vs. 16.0%, p = 0.043). For the prognostic efficacy of the combination of D-dimer ≥ 1.0 mg/L and MPV ≥ 8.1 fL in determining the need for intensive care, following values were determined: sensitivity: 57.7%, specificity: 70.8%, positive predictive value (PPV): 32.0%, negative predictive value (NPV): 84.0%, and accuracy: 63.0%. When D-dimer was ≥1.0, the median duration of treatment in MPV &lt;8.1 and ≥8.1 groups was 5.0 [interquartile range (IQR): 5.0–10.0] days for both groups (p = 0.64). The median length of hospital stay (LOS) was 7.0 (IQR: 5.0–10.5) days in the MPV &lt;8.1 group, while it was 8.5 (IQR: 5.0–16.3) days in the MPV ≥ 8.1 group (p = 0.17).

Conclusion

In COVID-19 patients with a serum D-dimer level of at least 1.0 mg/L and radiological bilateral infiltration at hospitalization, if the MPV value is ≥8.1, we could predict the need for intensive care with moderate efficacy and a relatively high negative predictive value. However, no correlation could be found between this combined marker and the duration of treatment and the LOS.

An Updated Review on the Role of Single Nucleotide Polymorphisms in COVID-19 Disease Severity: A Global Aspect

Abstract:

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and recently has become a serious global pandemic. Age, gender, and comorbidities are known to be common risk factors for severe COVID-19 but are not enough to fully explain the magnitude of their effect on the risk of severity of the disease. Single nucleotide polymorphisms (SNPs) in several genes have been reported as a genetic factor contributing to COVID-19 severity. This comprehensive review focuses on the association between SNPs in four important genes and COVID-19 severity in a global aspect. We discuss a total of 39 SNPs in this review: five SNPs in the ABO gene, nine SNPs in the angiotensin-converting enzyme 2 (ACE2) gene, 19 SNPs in the transmembrane protease serine 2 (TMPRSS2) gene, and six SNPs in the toll-like receptor 7 (TLR7) gene. These SNPs data could assist in monitoring an individual's risk of severe COVID-19 disease, and therefore personalized management and pharmaceutical treatment could be planned in COVID-19 patients.

What level of D-dimers can safely exclude pulmonary embolism in COVID-19 patients presenting to the emergency department?

OBJECTIVES

To identify which level of D-dimer would allow the safe exclusion of pulmonary embolism (PE) in COVID-19 patients presenting to the emergency department (ED).

METHODS

This retrospective study was conducted on the COVID database of Assistance Publique - Hôpitaux de Paris (AP-HP). COVID-19 patients who presented at the ED of AP-HP hospitals between March 1 and May 15, 2020, and had CTPA following D-dimer dosage within 48h of presentation were included. The D-dimer sensitivity, specificity, and positive and negative predictive values were calculated for different D-dimer thresholds, as well as the false-negative and failure rates, and the number of CTPAs potentially avoided.

RESULTS

A total of 781 patients (mean age 62.0 years, 53.8% men) with positive RT-PCR for SARS-Cov-2 were included and 60 of them (7.7%) had CTPA-confirmed PE. Their median D-dimer level was significantly higher than that of patients without PE (4,013 vs 1,198 ng·mL^-1, p < 0.001). Using 500 ng·mL^-1, or an age-adjusted cut-off for patients > 50 years, the sensitivity and the NPV were above 90%. With these thresholds, 17.1% and 31.5% of CTPAs could have been avoided, respectively. Four of the 178 patients who had a D-dimer below the age-adjusted cutoff had PE, leading to an acceptable failure rate of 2.2%. Using higher D-dimer cut-offs could have avoided more CTPAs, but would have lowered the sensitivity and increased the failure rate.

CONCLUSION

The same D-Dimer thresholds as those validated in non-COVID outpatients should be used to safely rule out PE.

KEY POINTS

• The median D-dimer level was significantly higher in COVID-19 patients with PE as compared to those without PE (4,013 ng·mL^-1 vs 1,198 ng·mL^-1 respectively, p < 0.001). • Using 500 ng·mL^-1, or an age-adjusted D-dimer cut-off to exclude pulmonary embolism, the sensitivity and negative predictive value were above 90%. • Higher cut-offs would lead to a reduction in the sensitivity below 85% and an increase in the failure rate, especially for patients under 50 years.

Contribution of the von Willebrand factor/ADAMTS13 imbalance to COVID-19 coagulopathy

The 2019 coronavirus disease (COVID-19) is the disease caused by SARS-CoV-2 infection. Although this infection has been shown to affect the respiratory system, a high incidence of thrombotic events has been observed in severe cases of COVID-19 and in a significant portion of COVID-19 nonsurvivors. Although prior literature has reported on both the coagulopathy and hypercoagulability of COVID-19, the specifics of coagulation have not been fully investigated. Observations of microthrombosis in patients with COVID-19 have brought attention to potential inflammatory endothelial injury. Von Willebrand factor (VWF) and its protease, A disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13), play an important homeostatic role in responding to endothelial injury. This report provides an overview of the literature investigating the role the VWF/ADAMTS13 axis may have in COVID-19 thrombotic events and suggests potential therapeutic strategies to prevent the progression of coagulopathy in patients with COVID-19.

Recent Findings on Platelet Activation, vWF Multimers and Other Thrombotic Biomarkers Associated with Critical COVID-19

Mortality rate in patients with COVID-19 increases in those admitted to the ICU. Activation of the coagulation system is associated with the worse disease outcomes. The aim of this study was to evaluate platelet activation and thrombotic biomarkers in hospitalized patients with COVID-19 during the second and third infection waves of the pandemic during 2021, following a previous report that included patients from the first wave. Sixty five patients were recruited and classified according to disease outcome; 10 healthy donors were included as a control group. Among prothrombotic biomarkers, t-PA concentrations ( p < .0001), PAI-1 (0.0032) and D dimer ( p = .0011) were higher in patients who developed critical COVID-19. We also found platelet activation via αIIbβIII expression ( p < .0001) and higher presence of vWF-HMWM in severe COVID-19 ( p < .0001). Several prothrombotic biomarkers are found to be increased since hospital admission in patients which lately present a worse disease outcome (ICU admission/death), among these, platelet activation, vWF increased plasma concentration and presence of HMWM seem to be of special interest. New studies regarding the predictive value of thrombotic biomarkers are needed as SARS-CoV-2 variants continue to emerge.

Adverse Outcome in COVID-19 Is Associated With an Aggravating Hypo-Responsive Platelet Phenotype

Thromboembolic complications are frequently observed in Coronavirus disease 2019 (COVID-19). While COVID-19 is linked to platelet dysregulation, the association between disease outcome and platelet function is less clear. We prospectively monitored platelet activation and reactivity in 97 patients during the first week of hospitalization and determined plasma markers of platelet degranulation and inflammation. Adverse outcome in COVID-19 was associated with increased basal platelet activation and diminished platelet responses, which aggravated over time. Especially GPIIb/IIIa responses were abrogated, pointing toward impeded platelet aggregation. Moreover, platelet-leukocyte aggregate formation was diminished, pointing toward abrogated platelet-mediated immune responses in COVID-19. No general increase in plasma levels of platelet-derived granule components could be detected, arguing against platelet exhaustion. However, studies on platelets from healthy donors showed that plasma components in COVID-19 patients with unfavorable outcome were at least partly responsible for diminished platelet responses. Taken together this study shows that unfavorable outcome in COVID-19 is associated with a hypo-responsive platelet phenotype that aggravates with disease progression and may impact platelet-mediated immunoregulation.

Effect of Crizanlizumab, a P-Selectin Inhibitor, in COVID-19: A Placebo-Controlled, Randomized Trial

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Severe COVID-19 is characterized by vascular inflammation and thrombosis, including elevations of P-selectin, a marker released by activated endothelial cells that mediates vascular inflammation.

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We tested the effect of crizanlizumab, an antibody to P-selectin, on biomarkers of inflammation and thrombosis in patients with COVID-19 in a randomized, placebo-controlled, double-blind clinical trial.

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Crizanlizumab decreased soluble P-selectin levels in patients with COVID-19.

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Crizanlizumab increased D-dimer and decreased prothrombin fragment 1.2 in patients with COVID-19.

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Crizanlizumab may induce endogenous thrombolysis in the setting of COVID-19.

COVID-19 is characterized by vascular inflammation and thrombosis, including elevations in P-selectin, a mediator of inflammation released by endothelial cells. We tested the effect of P-selectin inhibition on biomarkers of thrombosis and inflammation in patients with COVID-19. Hospitalized patients with moderate COVID-19 were randomly assigned to receive either placebo or crizanlizumab, a P-selectin inhibitor, in a double-blind fashion. Crizanlizumab reduced P-selectin levels by 89%. Crizanlizumab increased D-dimer levels by 77% and decreased prothrombin fragment. There were no significant differences between crizanlizumab and placebo for clinical endpoints. Crizanlizumab was well tolerated. Crizanlizumab may induce thrombolysis in the setting of COVID-19. (Crizanlizumab for Treating COVID-19 Vasculopathy [CRITICAL]; NCT04435184)

COVID-19 pneumonia imaging follow-up: when and how? A proposition from ESTI and ESR

Abstract

This document from the European Society of Thoracic Imaging (ESTI) and the European Society of Radiology (ESR) discusses the role of imaging in the long-term follow-up of COVID-19 patients, to define which patients may benefit from imaging, and what imaging modalities and protocols should be used. Insights into imaging features encountered on computed tomography (CT) scans and potential pitfalls are discussed and possible areas for future review and research are also included.

Key Points

• Post-COVID-19 pneumonia changes are mainly consistent with prior organizing pneumonia and are likely to disappear within 12 months of recovery from the acute infection in the majority of patients.

• At present, with the longest series of follow-up examinations reported not exceeding 12 months, the development of persistent or progressive fibrosis in at least some individuals cannot yet be excluded.

• Residual ground glass opacification may be associated with persisting bronchial dilatation and distortion, and might be termed “fibrotic-like changes” probably consistent with prior organizing pneumonia.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-021-08317-7.

Platelets in the perspective of COVID-19; pathophysiology of thrombocytopenia and its implication as prognostic and therapeutic opportunity

Despite endorsed and exponential research to improve diagnostic and therapeutic strategies, efforts have not yet converted into a better prospect for patients infected with the novel coronavirus (2019nCoV), and still, the name of SARS-CoV-2 is coupled with numerous unanswered questions. One of these questions is concerning how this respiratory virus reduces the number of platelets (PLTs)? The results of laboratory examinations showed that about a quarter of COVID-19 cases experience thrombocytopenia, and more remarkably, about half of these patients succumb to the infection due to coagulopathy. These findings have positioned PLTs as a pillar in the management as well as stratifying COVID-19 patients; however, not all the physicians came into a consensus about the prognostic value of these cells. The current review aims to unravel the contributory role of PLTs s in COVID-19; and also to summarize the original data obtained from international research laboratories on the association between COVID-19 and PLT production, activation, and clearance. In addition, we provide a special focus on the prognostic value of PLTs and their related parameters in COVID-19. Questions on how SARS-CoV-2 induces thrombocytopenia are also responded to. The last section provides a general overview of the most recent PLT- or thrombocytopenia-related therapeutic approaches. In conclusion, since SARS-CoV-2 reduces the number of PLTs by eliciting different mechanisms, treatment of thrombocytopenia in COVID-19 patients is not as simple as it appears and serious cautions should be considered to deal with the problem through scrutiny awareness of the causal mechanisms.

Thromboembolic Complications in Covid-19: From Clinical Scenario to Laboratory Evidence

SARS-Cov-2 infection, a pandemic disease since March 2020, is associated with a high percentage of cardiovascular complications mainly of a thromboembolic (TE) nature. Although clinical patterns have been described for the assessment of patients with increased risk, many TE complications occur in patients with apparently moderate risk. Notably, a recent statement from the European Society of Cardiology (ESC) atherosclerosis and vascular biology working group pointed out the key role of vascular endothelium for the recruitment of inflammatory and thrombotic pathways responsible for both disseminated intravascular coagulation and cardiovascular complications. Therefore, a better understanding of the pathophysiological process linking infection to increased TE risk is needed in order to understand the pathways of this dangerous liaison and possibly interrupt it with appropriate treatment. In this review, we describe the histological lesions and the related blood coagulation mechanisms involved in COVID-19, we define the laboratory parameters and clinical risk factors associated with TE events, and propose a prophylactic anticoagulation treatment in relation to the risk category. Finally, we highlight the concept that a solid risk assessment based on prospective multi-center data would be the challenge for a more precise risk stratification and more appropriate treatment.

C-reactive protein as a possible marker for severity and mortality of COVID-19 infection

AIM

The present study aimed to introduce a possible biomarker to differentiate between severe and fatal conditions of COVID-19.

BACKGROUND

The COVID-19 pandemic, appearing as a complicated health problem, has changed the lifestyle of people in recent years. Clinical findings indicate mild, severe, and fatal conditions of this disease. Prediction of disease severity is a significant point in managing COVID-19 infection.

METHODS

In this study, 195 differentially expressed genes (DEGs) that discriminate between fatal and severe conditions in patients were extracted from the literature and screened to determine the significant ones. The significant DEGs plus the 90 first neighbors added from the STRING database were included in the interactome using Cytoscape software v 3.7.2. The central nodes of the analyzed network were identified and assessed.

RESULTS

Ten significant DEGs were candidates for assessment, of which 9 were recognized by the STRING database. IL6, ALB, TNF, CRP, INS, MPO, C3, CXCL8, TTR, and TLR4 were determined as central nodes; IL6, CRP, and TTR were highlighted as the critical genes related to the severity of COVID-19 infection.

CONCLUSION

CRP was identified as the best possible biomarker with levels related to the severity and fatality of COVID-19 infection.