Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 20 de 46
Filter
1.
Cell Rep ; 37(13): 110167, 2021 12 28.
Article in English | MEDLINE | ID: covidwho-1596401

ABSTRACT

Cross-reactivity and direct killing of target cells remain underexplored for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-specific CD8+ T cells. Isolation of T cell receptors (TCRs) and overexpression in allogeneic cells allows for extensive T cell reactivity profiling. We identify SARS-CoV-2 RNA-dependent RNA polymerase (RdRp/NSP12) as highly conserved, likely due to its critical role in the virus life cycle. We perform single-cell TCRαß sequencing in human leukocyte antigen (HLA)-A∗02:01-restricted, RdRp-specific T cells from SARS-CoV-2-unexposed individuals. Human T cells expressing these TCRαß constructs kill target cell lines engineered to express full-length RdRp. Three TCR constructs recognize homologous epitopes from common cold coronaviruses, indicating CD8+ T cells can recognize evolutionarily diverse coronaviruses. Analysis of individual TCR clones may help define vaccine epitopes that can induce long-term immunity against SARS-CoV-2 and other coronaviruses.


Subject(s)
Coronavirus RNA-Dependent RNA Polymerase/immunology , HLA-A2 Antigen/immunology , SARS-CoV-2/immunology , CD8-Positive T-Lymphocytes/immunology , COVID-19/immunology , COVID-19/therapy , Cell Culture Techniques , Cross Reactions/immunology , Epitopes, T-Lymphocyte/immunology , HLA-A Antigens/immunology , HLA-A2 Antigen/genetics , Humans , Immunodominant Epitopes/immunology , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Leukocytes, Mononuclear/virology , RNA, Viral/genetics , Receptors, Antigen, T-Cell/immunology , Receptors, Antigen, T-Cell, alpha-beta/genetics , Receptors, Antigen, T-Cell, alpha-beta/immunology , SARS-CoV-2/pathogenicity , Spike Glycoprotein, Coronavirus/immunology
2.
Cells ; 10(12)2021 12 10.
Article in English | MEDLINE | ID: covidwho-1572376

ABSTRACT

To assess the biology of the lethal endpoint in patients with SARS-CoV-2 infection, we compared the transcriptional response to the virus in patients who survived or died during severe COVID-19. We applied gene expression profiling to generate transcriptional signatures for peripheral blood mononuclear cells (PBMCs) from patients with SARS-CoV-2 infection at the time when they were placed in the Intensive Care Unit of the Pavlov First State Medical University of St. Petersburg (Russia). Three different bioinformatics approaches to RNA-seq analysis identified a downregulation of three common pathways in survivors compared with nonsurvivors among patients with severe COVID-19, namely, low-density lipoprotein (LDL) particle receptor activity (GO:0005041), important for maintaining cholesterol homeostasis, leukocyte differentiation (GO:0002521), and cargo receptor activity (GO:0038024). Specifically, PBMCs from surviving patients were characterized by reduced expression of PPARG, CD36, STAB1, ITGAV, and ANXA2. Taken together, our findings suggest that LDL particle receptor pathway activity in patients with COVID-19 infection is associated with poor disease prognosis.


Subject(s)
COVID-19/genetics , Down-Regulation/genetics , Gene Expression Profiling , Receptors, LDL/genetics , Aged , COVID-19/virology , Gene Ontology , Gene Regulatory Networks , Humans , Leukocytes, Mononuclear/metabolism , Male , Middle Aged , RNA-Seq , SARS-CoV-2/physiology
3.
Brief Bioinform ; 22(5)2021 09 02.
Article in English | MEDLINE | ID: covidwho-1528156

ABSTRACT

The low capture rate of expressed RNAs from single-cell sequencing technology is one of the major obstacles to downstream functional genomics analyses. Recently, a number of imputation methods have emerged for single-cell transcriptome data, however, recovering missing values in very sparse expression matrices remains a substantial challenge. Here, we propose a new algorithm, WEDGE (WEighted Decomposition of Gene Expression), to impute gene expression matrices by using a biased low-rank matrix decomposition method. WEDGE successfully recovered expression matrices, reproduced the cell-wise and gene-wise correlations and improved the clustering of cells, performing impressively for applications with sparse datasets. Overall, this study shows a potent approach for imputing sparse expression matrix data, and our WEDGE algorithm should help many researchers to more profitably explore the biological meanings embedded in their single-cell RNA sequencing datasets. The source code of WEDGE has been released at https://github.com/QuKunLab/WEDGE.


Subject(s)
Algorithms , Computational Biology/methods , Gene Expression Profiling/methods , RNA-Seq/methods , Single-Cell Analysis/methods , COVID-19/blood , COVID-19/genetics , COVID-19/virology , Cluster Analysis , Computer Simulation , Genomics/methods , Humans , Leukocytes, Mononuclear/classification , Leukocytes, Mononuclear/metabolism , Reproducibility of Results , SARS-CoV-2/physiology , Severity of Illness Index
4.
Cell Transplant ; 30: 9636897211054481, 2021.
Article in English | MEDLINE | ID: covidwho-1511642

ABSTRACT

Biological and cellular interleukin-6 (IL-6)-related therapies have been used to treat severe COVID-19 pneumonia with hyperinflammatory syndrome and acute respiratory failure, which prompted further exploration of the role of IL-6 in human umbilical cord mesenchymal stem cell (hUCMSC) therapy. Peripheral blood mononuclear cells (PBMCs) were responders cocultured with hUCMSCs or exogenous IL-6. A PBMC suppression assay was used to analyze the anti-inflammatory effects via MTT assay. The IL-6 concentration in the supernatant was measured using ELISA. The correlation between the anti-inflammatory effect of hUCMSCs and IL-6 levels and the relevant roles of IL-6 and IL-6 mRNA expression was analyzed using the MetaCore functional network constructed from gene microarray data. The location of IL-6 and IL-6 receptor (IL-6R) expression was further evaluated. We reported that hUCMSCs did not initially exert any inhibitory effect on PHA-stimulated proliferation; however, a potent inhibitory effect on PHA-stimulated proliferation was observed, and the IL-6 concentration reached approximately 1000 ng/mL after 72 hours. Exogenous 1000 ng/mL IL-6 inhibited PHA-stimulated inflammation but less so than hUCMSCs. The inhibitory effects of hUCMSCs on PHA-stimulated PBMCs disappeared after adding an IL-6 neutralizing antibody or pretreatment with tocilizumab (TCZ), an IL-6R antagonist. hUCMSCs exert excellent anti-inflammatory effects by inducing higher IL-6 levels, which is different from TCZ. High concentration of IL-6 cytokine secretion plays an important role in the anti-inflammatory effect of hUCMSC therapy. Initial hUCMSC therapy, followed by TCZ, seems to optimize the therapeutic potential to treat COVID-19-related acute respiratory distress syndrome (ARDS).


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , COVID-19/complications , Interleukin-6/biosynthesis , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/metabolism , Respiratory Distress Syndrome/therapy , SARS-CoV-2 , Antibodies, Monoclonal, Humanized/pharmacology , Antibodies, Neutralizing/immunology , Cells, Cultured , Coculture Techniques , Combined Modality Therapy , DNA, Complementary/genetics , Gene Expression Regulation/drug effects , Humans , Inflammation , Interleukin-6/genetics , Interleukin-6/pharmacology , Leukocytes, Mononuclear/cytology , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Lymphocyte Activation/drug effects , Phytohemagglutinins/pharmacology , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Receptors, Interleukin-6/antagonists & inhibitors , Receptors, Interleukin-6/biosynthesis , Receptors, Interleukin-6/genetics , Respiratory Distress Syndrome/drug therapy , Respiratory Distress Syndrome/etiology , Umbilical Cord/cytology
5.
Int J Mol Sci ; 22(20)2021 Oct 18.
Article in English | MEDLINE | ID: covidwho-1470894

ABSTRACT

Infection caused by the severe acute respiratory syndrome coronavirus (SARS-CoV-2) in many cases is accompanied by the release of a large amount of proinflammatory cytokines in an event known as "cytokine storm", which is associated with severe coronavirus disease 2019 (COVID-19) cases and high mortality. The excessive production of proinflammatory cytokines is linked, inter alia, to the enhanced activity of receptors capable of recognizing the conservative regions of pathogens and cell debris, namely TLRs, TREM-1 and TNFR1. Here we report that peptides derived from innate immunity protein Tag7 inhibit activation of TREM-1 and TNFR1 receptors during acute inflammation. Peptides from the N-terminal fragment of Tag7 bind only to TREM-1, while peptides from the C-terminal fragment interact solely with TNFR1. Selected peptides are capable of inhibiting the production of proinflammatory cytokines both in peripheral blood mononuclear cells (PBMCs) from healthy donors and in vivo in the mouse model of acute lung injury (ALI) by diffuse alveolar damage (DAD). Treatment with peptides significantly decreases the infiltration of mononuclear cells to lungs in animals with DAD. Our findings suggest that Tag7-derived peptides might be beneficial in terms of the therapy or prevention of acute lung injury, e.g., for treating COVID-19 patients with severe pulmonary lesions.


Subject(s)
Acute Lung Injury/pathology , Cytokines/chemistry , Peptides/metabolism , Receptors, Tumor Necrosis Factor, Type I/metabolism , Triggering Receptor Expressed on Myeloid Cells-1/metabolism , Acute Lung Injury/metabolism , Animals , Cytokines/genetics , Cytokines/metabolism , Disease Models, Animal , Humans , Interferon-gamma/genetics , Interferon-gamma/metabolism , Leukocytes, Mononuclear/cytology , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Lipopolysaccharides/pharmacology , Lung/metabolism , Lung/pathology , Lymphocyte Activation/drug effects , Male , Mice , Mice, Inbred ICR , Peptides/chemistry , Peptides/pharmacology , Protein Binding , Receptors, Tumor Necrosis Factor, Type I/antagonists & inhibitors , Triggering Receptor Expressed on Myeloid Cells-1/antagonists & inhibitors
6.
Front Immunol ; 12: 744799, 2021.
Article in English | MEDLINE | ID: covidwho-1448731

ABSTRACT

Sepsis is a global health emergency, which is caused by various sources of infection that lead to changes in gene expression, protein-coding, and metabolism. Advancements in "omics" technologies have provided valuable tools to unravel the mechanisms involved in the pathogenesis of this disease. In this study, we performed shotgun mass spectrometry in peripheral blood mononuclear cells (PBMC) from septic patients (N=24) and healthy controls (N=9) and combined these results with two public microarray leukocytes datasets. Through combination of transcriptome and proteome profiling, we identified 170 co-differentially expressed genes/proteins. Among these, 122 genes/proteins displayed the same expression trend. Ingenuity Pathway Analysis revealed pathways related to lymphocyte functions with decreased status, and defense processes that were predicted to be strongly increased. Protein-protein interaction network analyses revealed two densely connected regions, which mainly included down-regulated genes/proteins that were related to the transcription of RNA, translation of proteins, and mitochondrial translation. Additionally, we identified one module comprising of up-regulated genes/proteins, which were mainly related to low-density neutrophils (LDNs). LDNs were reported in sepsis and in COVID-19. Changes in gene expression level were validated using quantitative real-time PCR in PBMCs from patients with sepsis. To further support that the source of the upregulated module of genes/proteins found in our results were derived from LDNs, we identified an increase of this population by flow cytometry in PBMC samples obtained from the same cohort of septic patients included in the proteomic analysis. This study provides new insights into a reprioritization of biological functions in response to sepsis that involved a transcriptional and translational shutdown of genes/proteins, with exception of a set of genes/proteins related to LDNs and host-defense system.


Subject(s)
Leukocytes, Mononuclear/metabolism , Neutrophils/metabolism , Sepsis/metabolism , Databases, Factual , Gene Expression Profiling , Gene Expression Regulation , Humans , Leukocytes, Mononuclear/cytology , Myeloid-Derived Suppressor Cells/cytology , Myeloid-Derived Suppressor Cells/metabolism , Neutrophils/cytology , Protein Interaction Maps , Proteomics , Sepsis/genetics , Sepsis/immunology
7.
Cell Rep ; 37(1): 109793, 2021 10 05.
Article in English | MEDLINE | ID: covidwho-1415261

ABSTRACT

The mortality risk of coronavirus disease 2019 (COVID-19) patients has been linked to the cytokine storm caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Understanding the inflammatory responses shared between COVID-19 and other infectious diseases that feature cytokine storms may therefore help in developing improved therapeutic strategies. Here, we use integrative analysis of single-cell transcriptomes to characterize the inflammatory signatures of peripheral blood mononuclear cells from patients with COVID-19, sepsis, and HIV infection. We identify ten hyperinflammatory cell subtypes in which monocytes are the main contributors to the transcriptional differences in these infections. Monocytes from COVID-19 patients share hyperinflammatory signatures with HIV infection and immunosuppressive signatures with sepsis. Finally, we construct a "three-stage" model of heterogeneity among COVID-19 patients, related to the hyperinflammatory and immunosuppressive signatures in monocytes. Our study thus reveals cellular and molecular insights about inflammatory responses to SARS-CoV-2 infection and provides therapeutic guidance to improve treatments for subsets of COVID-19 patients.


Subject(s)
COVID-19/blood , COVID-19/immunology , HIV Infections/blood , Leukocytes, Mononuclear/metabolism , SARS-CoV-2/immunology , Sepsis/blood , Transcriptome , COVID-19/virology , Cytokine Release Syndrome/blood , Cytokine Release Syndrome/immunology , Cytokines/blood , Data Analysis , Datasets as Topic , HIV Infections/immunology , HIV-1/immunology , Humans , Inflammation/blood , Leukocytes, Mononuclear/immunology , Sepsis/immunology , Single-Cell Analysis
8.
Front Immunol ; 12: 693269, 2021.
Article in English | MEDLINE | ID: covidwho-1389185

ABSTRACT

Chronic immune activation has been considered as the driving force for CD4+ T cell depletion in people infected with HIV-1. Interestingly, the normal immune profile of adult HIV-negative individuals living in Africa also exhibit chronic immune activation, reminiscent of that observed in HIV-1 infected individuals. It is characterized by increased levels of soluble immune activation markers, such as the cytokines interleukin (IL)-4, IL-10, TNF-α, and cellular activation markers including HLA-DR, CD-38, CCR5, coupled with reduced naïve and increased memory cells in CD4+ and CD8+ subsets. In addition, it is accompanied by low CD4+ T cell counts when compared to Europeans. There is also evidence that mononuclear cells from African infants secrete less innate cytokines than South and North Americans and Europeans in vitro. Chronic immune activation in Africans is linked to environmental factors such as parasitic infections and could be responsible for previously observed immune hypo-responsiveness to infections and vaccines. It is unclear whether the immunogenicity and effectiveness of anti-SARS-CoV-2 vaccines will also be reduced by similar mechanisms. A review of studies investigating this phenomenon is urgently required as they should inform the design and delivery for vaccines to be used in African populations.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , COVID-19 Vaccines/immunology , Immunogenicity, Vaccine/immunology , Lymphocyte Activation/immunology , SARS-CoV-2/immunology , ADP-ribosyl Cyclase 1/blood , Africa , CD4 Lymphocyte Count , CD8-Positive T-Lymphocytes/immunology , COVID-19/prevention & control , HLA-DR Antigens/blood , Humans , Interleukin-10/blood , Interleukin-4/blood , Leukocytes, Mononuclear/metabolism , Membrane Glycoproteins/blood , Receptors, CCR5/blood , Tumor Necrosis Factor-alpha/blood
9.
Int J Mol Sci ; 22(15)2021 Jul 26.
Article in English | MEDLINE | ID: covidwho-1374420

ABSTRACT

For the treatment of severe COVID-19, supplementation with human plasma-purified α-1 antitrypsin (AAT) to patients is currently considered. AAT inhibits host proteases that facilitate viral entry and possesses broad anti-inflammatory and immunomodulatory activities. Researchers have demonstrated that an interaction between SARS-CoV-2 spike protein (S) and lipopolysaccharides (LPS) enhances pro-inflammatory responses in vitro and in vivo. Hence, we wanted to understand the potential anti-inflammatory activities of plasma-derived and recombinant AAT (recAAT) in a model of human total peripheral blood mononuclear cells (PBMCs) exposed to a combination of CHO expressed trimeric spike protein and LPS, ex vivo. We confirmed that cytokine production was enhanced in PBMCs within six hours when low levels of LPS were combined with purified spike proteins ("spike"). In the presence of 0.5 mg/mL recAAT, however, LPS/spike-induced TNF-α and IL-1ß mRNA expression and protein release were significantly inhibited (by about 46-50%) relative to LPS/spike alone. Although without statistical significance, recAAT also reduced production of IL-6 and IL-8. Notably, under the same experimental conditions, the plasma-derived AAT preparation Respreeza (used in native and oxidized forms) did not show significant effects. Our findings imply that an early pro-inflammatory activation of human PBMCs is better controlled by the recombinant version of AAT than the human plasma-derived AAT used here. Considering the increasing clinical interest in AAT therapy as useful to ameliorate the hyper-inflammation seen during COVID-19 infection, different AAT preparations require careful evaluation.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Leukocytes, Mononuclear/metabolism , Spike Glycoprotein, Coronavirus/metabolism , alpha 1-Antitrypsin/pharmacology , Animals , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/immunology , CHO Cells , COVID-19/therapy , Cells, Cultured , Cricetulus , Cytokines/metabolism , Humans , Inflammation/metabolism , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/immunology , Lipopolysaccharides/immunology , Lipopolysaccharides/toxicity , SARS-CoV-2/drug effects , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , alpha 1-Antitrypsin/chemistry , alpha 1-Antitrypsin/immunology
10.
Sci Immunol ; 6(62)2021 08 10.
Article in English | MEDLINE | ID: covidwho-1352519

ABSTRACT

To understand how a protective immune response against SARS-CoV-2 develops over time, we integrated phenotypic, transcriptional and repertoire analyses on PBMCs from mild and severe COVID-19 patients during and after infection, and compared them to healthy donors (HD). A type I IFN-response signature marked all the immune populations from severe patients during the infection. Humoral immunity was dominated by IgG production primarily against the RBD and N proteins, with neutralizing antibody titers increasing post infection and with disease severity. Memory B cells, including an atypical FCRL5+ T-BET+ memory subset, increased during the infection, especially in patients with mild disease. A significant reduction of effector memory, CD8+ T cells frequency characterized patients with severe disease. Despite such impairment, we observed robust clonal expansion of CD8+ T lymphocytes, while CD4+ T cells were less expanded and skewed toward TCM and TH2-like phenotypes. MAIT cells were also expanded, but only in patients with mild disease. Terminally differentiated CD8+ GZMB+ effector cells were clonally expanded both during the infection and post-infection, while CD8+ GZMK+ lymphocytes were more expanded post-infection and represented bona fide memory precursor effector cells. TCR repertoire analysis revealed that only highly proliferating T cell clonotypes, which included SARS-CoV-2-specific cells, were maintained post-infection and shared between the CD8+ GZMB+ and GZMK+ subsets. Overall, this study describes the development of immunity against SARS-CoV-2 and identifies an effector CD8+ T cell population with memory precursor-like features.


Subject(s)
COVID-19/genetics , COVID-19/immunology , Host-Pathogen Interactions/immunology , Immunophenotyping , SARS-CoV-2/immunology , Transcriptome , Adult , Aged , Antibodies, Viral/immunology , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Biomarkers , COVID-19/virology , Cell Plasticity/genetics , Cell Plasticity/immunology , Clonal Evolution/immunology , Female , Gene Expression Profiling , Humans , Immunoglobulin Isotypes/immunology , Immunologic Memory , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Lymphocyte Count , Male , Middle Aged , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism
11.
Brief Bioinform ; 22(2): 1466-1475, 2021 03 22.
Article in English | MEDLINE | ID: covidwho-1343667

ABSTRACT

Coronavirus disease 2019 (COVID-19) has spread rapidly worldwide, causing significant mortality. There is a mechanistic relationship between intracellular coronavirus replication and deregulated autophagosome-lysosome system. We performed transcriptome analysis of peripheral blood mononuclear cells (PBMCs) from COVID-19 patients and identified the aberrant upregulation of genes in the lysosome pathway. We further determined the capability of two circulating markers, namely microtubule-associated proteins 1A/1B light chain 3B (LC3B) and (p62/SQSTM1) p62, both of which depend on lysosome for degradation, in predicting the emergence of moderate-to-severe disease in COVID-19 patients requiring hospitalization for supplemental oxygen therapy. Logistic regression analyses showed that LC3B was associated with moderate-to-severe COVID-19, independent of age, sex and clinical risk score. A decrease in LC3B concentration <5.5 ng/ml increased the risk of oxygen and ventilatory requirement (adjusted odds ratio: 4.6; 95% CI: 1.1-22.0; P = 0.04). Serum concentrations of p62 in the moderate-to-severe group were significantly lower in patients aged 50 or below. In conclusion, lysosome function is deregulated in PBMCs isolated from COVID-19 patients, and the related biomarker LC3B may serve as a novel tool for stratifying patients with moderate-to-severe COVID-19 from those with asymptomatic or mild disease. COVID-19 patients with a decrease in LC3B concentration <5.5 ng/ml will require early hospital admission for supplemental oxygen therapy and other respiratory support.


Subject(s)
COVID-19/virology , Leukocytes, Mononuclear/metabolism , Lysosomes/metabolism , Microtubule-Associated Proteins/blood , SARS-CoV-2/metabolism , Adult , Autophagy , Biomarkers/blood , COVID-19/blood , Cell Cycle , Cholesterol/metabolism , Female , Humans , Male , Middle Aged , RNA-Binding Proteins/blood , Real-Time Polymerase Chain Reaction , Retrospective Studies , Reverse Transcriptase Polymerase Chain Reaction
12.
Nucleic Acids Res ; 49(15): 8505-8519, 2021 09 07.
Article in English | MEDLINE | ID: covidwho-1328926

ABSTRACT

The transcriptomic diversity of cell types in the human body can be analysed in unprecedented detail using single cell (SC) technologies. Unsupervised clustering of SC transcriptomes, which is the default technique for defining cell types, is prone to group cells by technical, rather than biological, variation. Compared to de-novo (unsupervised) clustering, we demonstrate using multiple benchmarks that supervised clustering, which uses reference transcriptomes as a guide, is robust to batch effects and data quality artifacts. Here, we present RCA2, the first algorithm to combine reference projection (batch effect robustness) with graph-based clustering (scalability). In addition, RCA2 provides a user-friendly framework incorporating multiple commonly used downstream analysis modules. RCA2 also provides new reference panels for human and mouse and supports generation of custom panels. Furthermore, RCA2 facilitates cell type-specific QC, which is essential for accurate clustering of data from heterogeneous tissues. We demonstrate the advantages of RCA2 on SC data from human bone marrow, healthy PBMCs and PBMCs from COVID-19 patients. Scalable supervised clustering methods such as RCA2 will facilitate unified analysis of cohort-scale SC datasets.


Subject(s)
Algorithms , Cluster Analysis , RNA, Small Cytoplasmic/genetics , RNA-Seq/methods , Single-Cell Analysis/methods , Animals , Arthritis, Rheumatoid/genetics , Bone Marrow Cells/metabolism , COVID-19/blood , COVID-19/pathology , Cohort Studies , Datasets as Topic , Humans , Leukocytes, Mononuclear/metabolism , Leukocytes, Mononuclear/pathology , Mice , Organ Specificity , Quality Control , RNA-Seq/standards , Single-Cell Analysis/standards , Transcriptome
13.
Int J Mol Sci ; 22(15)2021 Jul 26.
Article in English | MEDLINE | ID: covidwho-1325683

ABSTRACT

For the treatment of severe COVID-19, supplementation with human plasma-purified α-1 antitrypsin (AAT) to patients is currently considered. AAT inhibits host proteases that facilitate viral entry and possesses broad anti-inflammatory and immunomodulatory activities. Researchers have demonstrated that an interaction between SARS-CoV-2 spike protein (S) and lipopolysaccharides (LPS) enhances pro-inflammatory responses in vitro and in vivo. Hence, we wanted to understand the potential anti-inflammatory activities of plasma-derived and recombinant AAT (recAAT) in a model of human total peripheral blood mononuclear cells (PBMCs) exposed to a combination of CHO expressed trimeric spike protein and LPS, ex vivo. We confirmed that cytokine production was enhanced in PBMCs within six hours when low levels of LPS were combined with purified spike proteins ("spike"). In the presence of 0.5 mg/mL recAAT, however, LPS/spike-induced TNF-α and IL-1ß mRNA expression and protein release were significantly inhibited (by about 46-50%) relative to LPS/spike alone. Although without statistical significance, recAAT also reduced production of IL-6 and IL-8. Notably, under the same experimental conditions, the plasma-derived AAT preparation Respreeza (used in native and oxidized forms) did not show significant effects. Our findings imply that an early pro-inflammatory activation of human PBMCs is better controlled by the recombinant version of AAT than the human plasma-derived AAT used here. Considering the increasing clinical interest in AAT therapy as useful to ameliorate the hyper-inflammation seen during COVID-19 infection, different AAT preparations require careful evaluation.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Leukocytes, Mononuclear/metabolism , Spike Glycoprotein, Coronavirus/metabolism , alpha 1-Antitrypsin/pharmacology , Animals , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/immunology , CHO Cells , COVID-19/therapy , Cells, Cultured , Cricetulus , Cytokines/metabolism , Humans , Inflammation/metabolism , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/immunology , Lipopolysaccharides/immunology , Lipopolysaccharides/toxicity , SARS-CoV-2/drug effects , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , alpha 1-Antitrypsin/chemistry , alpha 1-Antitrypsin/immunology
14.
Int J Mol Sci ; 22(14)2021 Jul 14.
Article in English | MEDLINE | ID: covidwho-1314666

ABSTRACT

Proinflammatory cytokine production following infection with severe acute respiratory syndrome coronavirus 2 (SARS CoV-2) is associated with poor clinical outcomes. Like SARS CoV-1, SARS CoV-2 enters host cells via its spike protein, which attaches to angiotensin-converting enzyme 2 (ACE2). As SARS CoV-1 spike protein is reported to induce cytokine production, we hypothesized that this pathway could be a shared mechanism underlying pathogenic immune responses. We herein compared the capabilities of Middle East Respiratory Syndrome (MERS), SARS CoV-1 and SARS CoV-2 spike proteins to induce cytokine expression in human peripheral blood mononuclear cells (PBMC). We observed that only specific commercial lots of SARS CoV-2 induce cytokine production. Surprisingly, recombinant SARS CoV-2 spike proteins from different vendors and batches exhibited different patterns of cytokine induction, and these activities were not inhibited by blockade of spike protein-ACE2 binding using either soluble ACE2 or neutralizing anti-S1 antibody. Moreover, commercial spike protein reagents contained varying levels of lipopolysaccharide (LPS), which correlated directly with their abilities to induce cytokine production. The LPS inhibitor, polymyxin B, blocked this cytokine induction activity. In addition, SARS CoV-2 spike protein avidly bound soluble LPS in vitro, rendering it a cytokine inducer. These results not only suggest caution in monitoring the purity of SARS CoV-2 spike protein reagents, but they indicate the possibility that interactions of SARS CoV-2 spike protein with LPS from commensal bacteria in virally infected mucosal tissues could promote pathogenic inflammatory cytokine production.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , Cytokines/metabolism , Leukocytes, Mononuclear/metabolism , Lipopolysaccharides/pharmacology , Models, Biological , Spike Glycoprotein, Coronavirus/pharmacology , Healthy Volunteers , Humans , In Vitro Techniques , Leukocytes, Mononuclear/drug effects
15.
J Infect Dis ; 224(1): 39-48, 2021 07 02.
Article in English | MEDLINE | ID: covidwho-1294730

ABSTRACT

BACKGROUND: Understanding the memory T-cell response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is crucial for assessing the longevity of protective immunity after SARS-CoV-2 infection or coronavirus disease 2019 (COVID-19) vaccination. However, the longitudinal memory T-cell response up to 8 months post-symptom onset (PSO) according to the severity of illness is unknown. METHODS: We analyzed peripheral blood mononuclear cells (PBMCs) from healthy volunteers or patients with COVID-19 who experienced asymptomatic, mild, or severe illness at 2, 5, and 8 months PSO. SARS-CoV-2 spike, nucleocapsid, and membrane protein-stimulated PBMCs were subjected to flow cytometry analysis. RESULTS: A total of 24 patients (7 asymptomatic, 9 with mild disease, and 8 with severe disease) and 6 healthy volunteers were analyzed. SARS-CoV-2-specific OX40+CD137+CD4+ T cells and CD69+CD137+CD8+ T cells persisted at 8 months PSO. Also, antigen-specific cytokine-producing or polyfunctional CD4+ T cells were maintained for up to 8 months PSO. Memory CD4+ T-cell responses tended to be greater in patients who had severe illness than in those with mild or asymptomatic disease. CONCLUSIONS: Memory response to SARS-CoV-2, based on the frequency and functionality, persists for 8 months PSO. Further investigations involving its longevity and protective effect from reinfection are warranted.


Subject(s)
COVID-19/immunology , COVID-19/virology , Host-Pathogen Interactions/immunology , Immunologic Memory , SARS-CoV-2/immunology , T-Lymphocyte Subsets/immunology , Adult , Aged , Antigens, Viral , Biomarkers , COVID-19/diagnosis , COVID-19/epidemiology , Case-Control Studies , Cytokines/metabolism , Disease Management , Epitopes, T-Lymphocyte/immunology , Female , Humans , Immunity, Cellular , Immunophenotyping , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Longitudinal Studies , Male , Middle Aged , Severity of Illness Index , Symptom Assessment , T-Lymphocyte Subsets/metabolism , Time Factors
16.
Front Immunol ; 12: 695242, 2021.
Article in English | MEDLINE | ID: covidwho-1282388

ABSTRACT

The COVID-19 pandemic has reached direct and indirect medical and social consequences with a subset of patients who rapidly worsen and die from severe-critical manifestations. As a result, there is still an urgent need to identify prognostic biomarkers and effective therapeutic approaches. Severe-critical manifestations of COVID-19 are caused by a dysregulated immune response. Immune checkpoint molecules such as Programmed death-1 (PD-1) and its ligand programmed death-ligand 1 (PD-L1) play an important role in regulating the host immune response and several lines of evidence underly the role of PD-1 modulation in COVID-19. Here, by analyzing blood sample collection from both hospitalized COVID-19 patients and healthy donors, as well as levels of PD-L1 RNA expression in a variety of model systems of SARS-CoV-2, including in vitro tissue cultures, ex-vivo infections of primary epithelial cells and biological samples obtained from tissue biopsies and blood sample collection of COVID-19 and healthy individuals, we demonstrate that serum levels of PD-L1 have a prognostic role in COVID-19 patients and that PD-L1 dysregulation is associated to COVID-19 pathogenesis. Specifically, PD-L1 upregulation is induced by SARS-CoV-2 in infected epithelial cells and is dysregulated in several types of immune cells of COVID-19 patients including monocytes, neutrophils, gamma delta T cells and CD4+ T cells. These results have clinical significance since highlighted the potential role of PD-1/PD-L1 axis in COVID-19, suggest a prognostic role of PD-L1 and provide a further rationale to implement novel clinical studies in COVID-19 patients with PD-1/PD-L1 inhibitors.


Subject(s)
B7-H1 Antigen/metabolism , COVID-19/metabolism , Adult , Aged , Aged, 80 and over , COVID-19/diagnosis , COVID-19/pathology , Epithelial Cells/metabolism , Female , Humans , Leukocytes, Mononuclear/metabolism , Lung/metabolism , Lung/pathology , Male , Middle Aged , Prognosis , SARS-CoV-2 , Up-Regulation
17.
Front Immunol ; 12: 665329, 2021.
Article in English | MEDLINE | ID: covidwho-1268251

ABSTRACT

Infection by novel coronavirus SARS-CoV-2 causes different presentations of COVID-19 and some patients may progress to a critical, fatal form of the disease that requires their admission to ICU and invasive mechanical ventilation. In order to predict in advance which patients could be more susceptible to develop a critical form of COVID-19, it is essential to define the most adequate biomarkers. In this study, we analyzed several parameters related to the cellular immune response in blood samples from 109 patients with different presentations of COVID-19 who were recruited in Hospitals and Primary Healthcare Centers in Madrid, Spain, during the first pandemic peak between April and June 2020. Hospitalized patients with the most severe forms of COVID-19 showed a potent inflammatory response that was not translated into an efficient immune response. Despite the high levels of effector cytotoxic cell populations such as NK, NKT and CD8+ T cells, they displayed immune exhaustion markers and poor cytotoxic functionality against target cells infected with pseudotyped SARS-CoV-2 or cells lacking MHC class I molecules. Moreover, patients with critical COVID-19 showed low levels of the highly cytotoxic TCRγδ+ CD8+ T cell subpopulation. Conversely, CD4 count was greatly reduced in association to high levels of Tregs, low plasma IL-2 and impaired Th1 differentiation. The relative importance of these immunological parameters to predict COVID-19 severity was analyzed by Random Forest algorithm and we concluded that the most important features were related to an efficient cytotoxic response. Therefore, efforts to fight against SARS-CoV-2 infection should be focused not only to decrease the disproportionate inflammatory response, but also to elicit an efficient cytotoxic response against the infected cells and to reduce viral replication.


Subject(s)
COVID-19/epidemiology , COVID-19/immunology , Cytotoxicity, Immunologic , Intensive Care Units , Leukocytes, Mononuclear/immunology , Patient Admission/statistics & numerical data , SARS-CoV-2/immunology , Adult , Aged , Aged, 80 and over , Antibodies, Viral/blood , Antibodies, Viral/immunology , Biomarkers , COVID-19/diagnosis , COVID-19/virology , Comorbidity , Cytokines/metabolism , Female , Humans , Immunophenotyping , Leukocytes, Mononuclear/metabolism , Male , Middle Aged , Severity of Illness Index , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism
18.
Front Immunol ; 12: 651656, 2021.
Article in English | MEDLINE | ID: covidwho-1211812

ABSTRACT

Although immune dysfunction is a key feature of coronavirus disease 2019 (COVID-19), the metabolism-related mechanisms remain elusive. Here, by reanalyzing single-cell RNA sequencing data, we delineated metabolic remodeling in peripheral blood mononuclear cells (PBMCs) to elucidate the metabolic mechanisms that may lead to the progression of severe COVID-19. After scoring the metabolism-related biological processes and signaling pathways, we found that mono-CD14+ cells expressed higher levels of glycolysis-related genes (PKM, LDHA and PKM) and PPP-related genes (PGD and TKT) in severe patients than in mild patients. These genes may contribute to the hyperinflammation in mono-CD14+ cells of patients with severe COVID-19. The mono-CD16+ cell population in COVID-19 patients showed reduced transcription levels of genes related to lysine degradation (NSD1, KMT2E, and SETD2) and elevated transcription levels of genes involved in OXPHOS (ATP6V1B2, ATP5A1, ATP5E, and ATP5B), which may inhibit M2-like polarization. Plasma cells also expressed higher levels of the OXPHOS gene ATP13A3 in COVID-19 patients, which was positively associated with antibody secretion and survival of PCs. Moreover, enhanced glycolysis or OXPHOS was positively associated with the differentiation of memory B cells into plasmablasts or plasma cells. This study comprehensively investigated the metabolic features of peripheral immune cells and revealed that metabolic changes exacerbated inflammation in monocytes and promoted antibody secretion and cell survival in PCs in COVID-19 patients, especially those with severe disease.


Subject(s)
COVID-19/immunology , Glycolysis/genetics , Lysine/metabolism , Monocytes/metabolism , Single-Cell Analysis/methods , Adenosine Triphosphatases/blood , Adenosine Triphosphatases/genetics , Antibodies/metabolism , COVID-19/metabolism , COVID-19/physiopathology , Databases, Genetic , GPI-Linked Proteins/metabolism , Gene Ontology , Hematopoiesis/genetics , Humans , Inflammation/genetics , Inflammation/immunology , Inflammation/metabolism , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Leukocytes, Mononuclear/pathology , Lipopolysaccharide Receptors/metabolism , Lysine/genetics , Membrane Transport Proteins/blood , Membrane Transport Proteins/genetics , Metabolic Networks and Pathways/genetics , Metabolic Networks and Pathways/physiology , Monocytes/immunology , Monocytes/pathology , Oxidative Phosphorylation , RNA-Seq , Receptors, IgG/metabolism , Signal Transduction/genetics , Signal Transduction/immunology , Transcriptome/genetics
19.
Int Immunopharmacol ; 97: 107641, 2021 Aug.
Article in English | MEDLINE | ID: covidwho-1198829

ABSTRACT

BACKGROUND: When a new pathogen, such as severe acute respiratory syndrome coronavirus 2, appears all novel information can aid in the process of monitoring and in the diagnosis of the coronavirus disease (COVID-19). The aim of the current study is to elucidate the specific miRNA profile which can act as new biomarkers for distinguishing acute COVID-19 disease from the healthy group and those in the post-acute phase of the COVID-19 disease. METHODS: The expression level of selected miRNAs including let-7b-3p, miR-29a-3p, miR-146a-3p and miR-155-5p were evaluated in peripheral blood mononuclear cells (PBMCs) of COVID-19 patients, in both the acute and post-acute COVID-19 phase of the disease and healthy groups, by real-time PCR assays. Specificity and sensitivity of miRNAs was tested by receiver operating characteristic (ROC) analysis in COVID-19 patients. RESULTS: The expression level of all miRNAs in COVID-19 patients was significantly higher than in the healthy group. Therefore, the expression pattern of miR-29a-3p, miR-146a-3p and let-7b-3p in the post-acute COVID-19 phase was significantly different from the acute COVID-19 phase. ROC analyses demonstrated that miR-29a-3p, -155-5p and -146a-3p may serve as the novel biomarker for COVID-19 diagnosis with high specificity and sensitivity. In addition, miR-29a-3p, and -146a-3p can maybe act as novel biomarkers for distinguishing acute from post-acute phase of COVID-19 disease. DISCUSSION: The difference in miRNA expression pattern between COVID-19 patients and those in the healthy group, and between acute COVID-19 with post-acute COVID-19, suggested that cellular miRNAs could be used as promising biomarkers for diagnosis and monitoring of COVID-19.


Subject(s)
COVID-19/blood , COVID-19/diagnosis , Leukocytes, Mononuclear/metabolism , MicroRNAs/biosynthesis , Acute Disease , Adult , Aged , Biomarkers/blood , Female , Gene Expression Profiling , Healthy Volunteers , Humans , Male , Middle Aged , ROC Curve , Real-Time Polymerase Chain Reaction
20.
Inflammation ; 44(5): 1865-1877, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1188133

ABSTRACT

An understanding of the pathological inflammatory mechanisms involved in SARS-CoV-2 virus infection is necessary in order to discover new molecular pharmacological targets for SARS-CoV-2 cytokine storm. In this study, the effects of a recombinant SARS-CoV-2 spike glycoprotein S1 was investigated in human peripheral blood mononuclear cells (PBMCs). Stimulation of PBMCs with spike glycoprotein S1 (100 ng/mL) resulted in significant elevation in the production of TNFα, IL-6, IL-1ß and IL-8. However, pre-treatment with dexamethasone (100 nM) caused significant reduction in the release of these cytokines. Further experiments revealed that S1 stimulation of PBMCs increased phosphorylation of NF-κB p65 and IκBα, and IκBα degradation. DNA binding of NF-κB p65 was also significantly increased following stimulation with spike glycoprotein S1. Treatment of PBMCs with dexamethasone (100 nM) or BAY11-7082 (1 µM) resulted in inhibition of spike glycoprotein S1-induced NF-κB activation. Activation of p38 MAPK by S1 was blocked in the presence of dexamethasone and SKF 86002. CRID3, but not dexamethasone pre-treatment, produced significant inhibition of S1-induced activation of NLRP3/caspase-1. Further experiments revealed that S1-induced increase in the production of TNFα, IL-6, IL-1ß and IL-8 was reduced in the presence of BAY11-7082 and SKF 86002, while CRID3 pre-treatment resulted in the reduction of IL-1ß production. These results suggest that SARS-CoV-2 spike glycoprotein S1 stimulated PBMCs to release pro-inflammatory cytokines through mechanisms involving activation of NF-κB, p38 MAPK and NLRP3 inflammasome. It is proposed that the clinical benefits of dexamethasone in COVID-19 are possibly due to its anti-inflammatory activity in reducing SARS-CoV-2 cytokine storm.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Cytokine Release Syndrome/virology , Cytokines/metabolism , Dexamethasone/pharmacology , Leukocytes, Mononuclear/metabolism , SARS-CoV-2/pathogenicity , Spike Glycoprotein, Coronavirus/immunology , Anti-Inflammatory Agents/therapeutic use , Biomarkers/metabolism , Blotting, Western , COVID-19/drug therapy , COVID-19/immunology , COVID-19/virology , Cells, Cultured , Cytokine Release Syndrome/drug therapy , Cytokine Release Syndrome/immunology , Cytokine Release Syndrome/metabolism , Dexamethasone/therapeutic use , Enzyme-Linked Immunosorbent Assay , Humans , Leukocytes, Mononuclear/drug effects , Recombinant Proteins/immunology , SARS-CoV-2/immunology
SELECTION OF CITATIONS
SEARCH DETAIL
...