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1.
Front Immunol ; 13: 842740, 2022.
Article in English | MEDLINE | ID: covidwho-1903003

ABSTRACT

Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains a significant global health emergency with new variants in some cases evading current therapies and approved vaccines. COVID-19 presents with a broad spectrum of acute and long-term manifestations. Severe COVID-19 is characterized by dysregulated cytokine release profile, dysfunctional immune responses, and hypercoagulation with a high risk of progression to multi-organ failure and death. Unraveling the fundamental immunological processes underlying the clinical manifestations of COVID-19 is vital for the identification and design of more effective therapeutic interventions for individuals at the highest risk of severe outcomes. Caspases are expressed in both immune and non-immune cells and mediate inflammation and cell death, including apoptosis and pyroptosis. Here we review accumulating evidence defining the importance of the expression and activity of caspase family members following SARS-CoV-2 infection and disease. Research suggests SARS-CoV-2 infection is linked to the function of multiple caspases, both mechanistically in vitro as well as in observational studies of individuals with severe COVID-19, which may further the impact on disease severity. We also highlight immunological mechanisms that occur in severe COVID-19 pathology upstream and downstream of activated caspase pathways, including innate recognition receptor signaling, inflammasomes, and other multiprotein complex assembly, inflammatory mediators IL-1ß and IL-18, and apoptotic and pyroptotic cell death. Finally, we illuminate discriminate and indiscriminate caspase inhibitors that have been identified for clinical use that could emerge as potential therapeutic interventions that may benefit clinical efforts to prevent or ameliorate severe COVID-19.


Subject(s)
COVID-19/enzymology , Caspases/immunology , SARS-CoV-2 , Animals , COVID-19/drug therapy , COVID-19/immunology , Humans , Inflammation/immunology
2.
J Immunol ; 207(5): 1275-1287, 2021 09 01.
Article in English | MEDLINE | ID: covidwho-1771322

ABSTRACT

The airway epithelial cells (AECs) lining the conducting passageways of the lung secrete a variety of immunomodulatory factors. Among these, PGE2 limits lung inflammation and promotes bronchodilation. By contrast, IL-6 drives intense airway inflammation, remodeling, and fibrosis. The signaling that differentiates the production of these opposing mediators is not understood. In this study, we find that the production of PGE2 and IL-6 following stimulation of human AECs by the damage-associated molecular pattern extracellular ATP shares a common requirement for Ca2+ release-activated Ca2+ (CRAC) channels. ATP-mediated synthesis of PGE2 required activation of metabotropic P2Y2 receptors and CRAC channel-mediated cytosolic phospholipase A2 signaling. By contrast, ATP-evoked synthesis of IL-6 occurred via activation of ionotropic P2X receptors and CRAC channel-mediated calcineurin/NFAT signaling. In contrast to ATP, which elicited the production of both PGE2 and IL-6, the uridine nucleotide, UTP, stimulated PGE2 but not IL-6 production. These results reveal that human AECs employ unique receptor-specific signaling mechanisms with CRAC channels as a signaling nexus to regulate release of opposing immunomodulatory mediators. Collectively, our results identify P2Y2 receptors, CRAC channels, and P2X receptors as potential intervention targets for airway diseases.


Subject(s)
Dinoprostone/metabolism , Inflammation/immunology , Interleukin-6/metabolism , Respiratory Mucosa/metabolism , Adenosine Triphosphate/pharmacokinetics , Alarmins/metabolism , Calcium Release Activated Calcium Channels/metabolism , Cells, Cultured , Humans , Immunomodulation , Interleukin-6/genetics , NFATC Transcription Factors/metabolism , Phospholipases A2/metabolism , Receptors, Purinergic P2X/metabolism , Respiratory Mucosa/pathology , Signal Transduction , Uracil Nucleotides/metabolism
3.
Nat Immunol ; 23(4): 532-542, 2022 04.
Article in English | MEDLINE | ID: covidwho-1764192

ABSTRACT

The use of lipid-formulated RNA vaccines for cancer or COVID-19 is associated with dose-limiting systemic inflammatory responses in humans that were not predicted from preclinical studies. Here, we show that the 'interleukin 1 (IL-1)-interleukin 1 receptor antagonist (IL-1ra)' axis regulates vaccine-mediated systemic inflammation in a host-specific manner. In human immune cells, RNA vaccines induce production of IL-1 cytokines, predominantly IL-1ß, which is dependent on both the RNA and lipid formulation. IL-1 in turn triggers the induction of the broad spectrum of pro-inflammatory cytokines (including IL-6). Unlike humans, murine leukocytes respond to RNA vaccines by upregulating anti-inflammatory IL-1ra relative to IL-1 (predominantly IL-1α), protecting mice from cytokine-mediated toxicities at >1,000-fold higher vaccine doses. Thus, the IL-1 pathway plays a key role in triggering RNA vaccine-associated innate signaling, an effect that was unexpectedly amplified by certain lipids used in vaccine formulations incorporating N1-methyl-pseudouridine-modified RNA to reduce activation of Toll-like receptor signaling.


Subject(s)
Inflammation , Interleukin 1 Receptor Antagonist Protein , Interleukin-1 , Animals , COVID-19 , Inflammation/immunology , Inflammation/metabolism , Interleukin 1 Receptor Antagonist Protein/genetics , Interleukin 1 Receptor Antagonist Protein/immunology , Interleukin-1/genetics , Interleukin-1/immunology , Lipids , Mice , RNA , Vaccines, Synthetic , mRNA Vaccines/adverse effects , mRNA Vaccines/metabolism
4.
Immunol Lett ; 243: 19-27, 2022 Mar.
Article in English | MEDLINE | ID: covidwho-1734546

ABSTRACT

The interest in the process of aging, and specifically in how aging affects the working of our immune system, has recently enormously grown among both specialists (immunologists and gerontologists) and representatives of other disciplines of health sciences. An obvious reason for this interest is the current pandemics of COVID-19, known to affect the elderly more than younger people. In this paper current knowledge about mechanisms and complex facets of human immune system aging is presented, stemming from the knowledge about the working of various parts of the immune system, and leading to understanding of immunological mechanisms of chronic, inflammatory, aging-related diseases and of COVID-19.


Subject(s)
Aging/physiology , Immune System/immunology , Inflammation/immunology , SARS-CoV-2/physiology , Aged , Animals , COVID-19 , Humans , Immunosenescence
5.
Int J Mol Sci ; 23(5)2022 Mar 06.
Article in English | MEDLINE | ID: covidwho-1732070

ABSTRACT

Almost two years have passed since the outbreak reported for the first time in Wuhan of coronavirus disease 2019 (COVID-19), due to severe acute respiratory syndrome (SARS)-CoV-2 coronavirus, rapidly evolved into a pandemic. This infectious disease has stressed global health care systems. The mortality rate is higher, particularly in elderly population and in patients with comorbidities such as hypertension, diabetes mellitus, cardiovascular disease, chronic lung disease, chronic renal disease, and malignancy. Among them, subjects with diabetes have a high risk of developing severe form of COVID-19 and show increased mortality. How diabetes contributes to COVID-19 severity remains unclear. It has been hypothesized that it may be correlated with the effects of hyperglycemia on systemic inflammatory responses and immune system dysfunction. Vitamin D (VD) is a modulator of immune-response. Data from literature showed that vitamin D deficiency in COVID-19 patients increases COVID-19 severity, likely because of its negative impact on immune and inflammatory responses. Therefore, the use of vitamin D might play a role in some aspects of the infection, particularly the inflammatory state and the immune system function of patients. Moreover, a piece of evidence highlighted a link among vitamin D deficiency, obesity and diabetes, all factors associated with COVID-19 severity. Given this background, we performed an overview of the systematic reviews to assess the association between vitamin D supplementation and inflammatory markers in patients with diabetes; furthermore, vitamin D's possible role in COVID-19 patients was assessed as well. Three databases, namely MEDLINE, PubMed Central and the Cochrane Library of Systematic Reviews, were reviewed to retrieve the pertinent data. The aim of this review is to provide insight into the recent advances about the molecular basis of the relationship between vitamin D, immune response, inflammation, diabetes and COVID-19.


Subject(s)
COVID-19/immunology , Diabetes Mellitus/immunology , Immune System/immunology , Inflammation/immunology , Obesity/immunology , Vitamin D/immunology , COVID-19/virology , Humans , Immune System/drug effects , Meta-Analysis as Topic , SARS-CoV-2/physiology , Systematic Reviews as Topic , T-Lymphocytes, Regulatory/drug effects , T-Lymphocytes, Regulatory/immunology , Vitamin D/administration & dosage , Vitamins/administration & dosage , Vitamins/immunology
6.
Nutrients ; 12(6)2020 May 27.
Article in English | MEDLINE | ID: covidwho-1725878

ABSTRACT

The coronavirus-disease 2019 (COVID-19) was announced as a global pandemic by the World Health Organization. Challenges arise concerning how to optimally support the immune system in the general population, especially under self-confinement. An optimal immune response depends on an adequate diet and nutrition in order to keep infection at bay. For example, sufficient protein intake is crucial for optimal antibody production. Low micronutrient status, such as of vitamin A or zinc, has been associated with increased infection risk. Frequently, poor nutrient status is associated with inflammation and oxidative stress, which in turn can impact the immune system. Dietary constituents with especially high anti-inflammatory and antioxidant capacity include vitamin C, vitamin E, and phytochemicals such as carotenoids and polyphenols. Several of these can interact with transcription factors such as NF-kB and Nrf-2, related to anti-inflammatory and antioxidant effects, respectively. Vitamin D in particular may perturb viral cellular infection via interacting with cell entry receptors (angiotensin converting enzyme 2), ACE2. Dietary fiber, fermented by the gut microbiota into short-chain fatty acids, has also been shown to produce anti-inflammatory effects. In this review, we highlight the importance of an optimal status of relevant nutrients to effectively reduce inflammation and oxidative stress, thereby strengthening the immune system during the COVID-19 crisis.


Subject(s)
Coronavirus Infections , Diet , Immune System/immunology , Inflammation/immunology , Nutrients/immunology , Oxidative Stress/immunology , Pandemics , Pneumonia, Viral , Antioxidants , Betacoronavirus , COVID-19 , Coronavirus Infections/immunology , Humans , Inflammation/prevention & control , Nutritional Status/immunology , Pneumonia, Viral/immunology , SARS-CoV-2
7.
Brain Behav Immun ; 87: 53-54, 2020 07.
Article in English | MEDLINE | ID: covidwho-1719338

ABSTRACT

While all groups are affected by the COVID-19 pandemic, the elderly, underrepresented minorities, and those with underlying medical conditions are at the greatest risk. The high rate of consumption of diets high in saturated fats, sugars, and refined carbohydrates (collectively called Western diet, WD) worldwide, contribute to the prevalence of obesity and type 2 diabetes, and could place these populations at an increased risk for severe COVID-19 pathology and mortality. WD consumption activates the innate immune system and impairs adaptive immunity, leading to chronic inflammation and impaired host defense against viruses. Furthermore, peripheral inflammation caused by COVID-19 may have long-term consequences in those that recover, leading to chronic medical conditions such as dementia and neurodegenerative disease, likely through neuroinflammatory mechanisms that can be compounded by an unhealthy diet. Thus, now more than ever, wider access to healthy foods should be a top priority and individuals should be mindful of healthy eating habits to reduce susceptibility to and long-term complications from COVID-19.


Subject(s)
Coronavirus Infections/epidemiology , Diabetes Mellitus, Type 2/epidemiology , Diet, Western/statistics & numerical data , Inflammation/epidemiology , Obesity/epidemiology , Pneumonia, Viral/epidemiology , Adaptive Immunity/immunology , Betacoronavirus , COVID-19 , Coronavirus Infections/immunology , Dementia/epidemiology , Dementia/immunology , Diabetes Mellitus, Type 2/immunology , Diet , Disease Susceptibility , Humans , Immunity, Innate/immunology , Inflammation/immunology , Neurodegenerative Diseases/epidemiology , Neurodegenerative Diseases/immunology , Nutritional Status , Obesity/immunology , Pandemics , Pneumonia, Viral/immunology , SARS-CoV-2
8.
Front Immunol ; 12: 813300, 2021.
Article in English | MEDLINE | ID: covidwho-1690445

ABSTRACT

Background: The presentation of SARS-CoV-2 infection varies from asymptomatic to severe COVID-19. Similarly, high variability in the presence, titre and duration of specific antibodies has been reported. While some host factors determining these differences, such as age and ethnicity have been identified, the underlying molecular mechanisms underpinning these differences remain poorly defined. Methods: We analysed serum and PBMC from 17 subjects with a previous PCR-confirmed SARS-CoV-2 infection and 10 unexposed volunteers following the first wave of the pandemic, in the UK. Anti-NP IgG and neutralising antibodies were measured, as well as a panel of infection and inflammation related cytokines. The virus-specific T cell response was determined by IFN-γ ELISPOT and flow cytometry after overnight incubation of PBMCs with pools of selected SARS-CoV-2 specific peptides. Results: Seven of 17 convalescent subjects had undetectable levels of anti-NP IgG, and a positive correlation was shown between anti-NP IgG levels and the titre of neutralising antibodies (IC50). In contrast, a discrepancy was noted between antibody levels and T cell IFN-γ production by ELISpot following stimulation with specific peptides. Among the analysed cytokines, ß-NGF and IL-1α levels were significantly different between anti-NP positive and negative subjects, and only ß-NGF significantly correlated with anti-NP positivity. Interestingly, CD4+ T cells of anti-NP negative subjects expressed lower amounts of the ß-NGF-specific receptor TrkA. Conclusions: Our results suggest that the ß-NGF/TrkA signalling pathway is associated with the production of anti-NP specific antibody in mild SARS-CoV-2 infection and the mechanistic regulation of this pathway in COVID-19 requires further investigation.


Subject(s)
Antibodies, Anti-Idiotypic/immunology , COVID-19/immunology , Immunoglobulin G/immunology , Nerve Growth Factor/immunology , Nucleoproteins/immunology , Receptor, trkA/immunology , Signal Transduction/immunology , Animals , Antibodies, Viral/immunology , CD4-Positive T-Lymphocytes/immunology , Cell Line , Chlorocebus aethiops , Cytokines/immunology , Humans , Inflammation/immunology , SARS-CoV-2/immunology , Vero Cells
9.
Cells ; 11(4)2022 02 13.
Article in English | MEDLINE | ID: covidwho-1686622

ABSTRACT

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is the pathogenic agent of Coronavirus-Induced Disease-2019 (COVID-19), a multi-organ syndrome which primarily targets the respiratory system. In this review, considering the large amount of data pointing out the role of the Aryl hydrocarbon Receptor (AhR) in the inflammatory response and in the modulation of innate and adaptive immunity, we describe some mechanisms that strongly suggest its involvement in the management of COVID-19's inflammatory framework. It regulates both the expression of Angiotensin Converting Enzyme-2 (ACE-2) and its stabilizing partner, the Broad neutral Amino acid Transporter 1 (B0AT1). It induces Indolamine 2,3 dioxygenase (IDO-1), the enzyme which, starting from Tryptophan (Trp), produces Kynurenine (Kyn, Beta-Anthraniloyl-L-Alanine). The accumulation of Kyn and the depletion of Trp arrest T cell growth and induce apoptosis, setting up an immune-tolerant condition, whereas AhR and interferon type I (IFN-I) build a mutual inhibitory loop that also involves NF-kB and limits the innate response. AhR/Kyn binding boosts the production of Interleukin-6 (IL-6), thus reinforcing the inflammatory state and counteracting the IDO-dependent immune tolerance in the later stage of COVID-19. Taken together, these data depict a framework where sufficient clues suggest the possible participation of AhR in the management of COVID-19 inflammation, thus indicating an additional therapeutic target for this disease.


Subject(s)
COVID-19/metabolism , Receptors, Aryl Hydrocarbon/metabolism , SARS-CoV-2/metabolism , Adaptive Immunity/immunology , Amino Acid Transport Systems, Neutral/metabolism , Angiotensin-Converting Enzyme 2/metabolism , Basic Helix-Loop-Helix Transcription Factors/metabolism , Basic Helix-Loop-Helix Transcription Factors/physiology , COVID-19/immunology , COVID-19/transmission , Humans , Immunity, Innate/immunology , Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism , Inflammation/immunology , Kynurenine/metabolism , Receptors, Aryl Hydrocarbon/physiology , SARS-CoV-2/pathogenicity , Signal Transduction , Tryptophan/metabolism
10.
Sci Immunol ; 7(68): eabf2846, 2022 02 11.
Article in English | MEDLINE | ID: covidwho-1685480

ABSTRACT

Macrophages regulate protective immune responses to infectious microbes, but aberrant macrophage activation frequently drives pathological inflammation. To identify regulators of vigorous macrophage activation, we analyzed RNA-seq data from synovial macrophages and identified SLAMF7 as a receptor associated with a superactivated macrophage state in rheumatoid arthritis. We implicated IFN-γ as a key regulator of SLAMF7 expression and engaging SLAMF7 drove a strong wave of inflammatory cytokine expression. Induction of TNF-α after SLAMF7 engagement amplified inflammation through an autocrine signaling loop. We observed SLAMF7-induced gene programs not only in macrophages from rheumatoid arthritis patients but also in gut macrophages from patients with active Crohn's disease and in lung macrophages from patients with severe COVID-19. This suggests a central role for SLAMF7 in macrophage superactivation with broad implications in human disease pathology.


Subject(s)
Inflammation/immunology , Macrophage Activation/immunology , Signaling Lymphocytic Activation Molecule Family/immunology , Transcriptome/immunology , Acute Disease , Adult , Arthritis, Rheumatoid/genetics , Arthritis, Rheumatoid/immunology , Arthritis, Rheumatoid/metabolism , COVID-19/genetics , COVID-19/immunology , COVID-19/metabolism , COVID-19/virology , Cells, Cultured , Chronic Disease , Crohn Disease/genetics , Crohn Disease/immunology , Crohn Disease/metabolism , Female , Humans , Inflammation/genetics , Inflammation/metabolism , Macrophage Activation/genetics , RNA-Seq/methods , Reverse Transcriptase Polymerase Chain Reaction/methods , SARS-CoV-2/immunology , SARS-CoV-2/physiology , Signaling Lymphocytic Activation Molecule Family/genetics , Signaling Lymphocytic Activation Molecule Family/metabolism , Single-Cell Analysis/methods , Synovial Membrane/immunology , Synovial Membrane/metabolism , Synovial Membrane/pathology , Transcriptome/genetics
12.
Cell Death Dis ; 13(2): 137, 2022 02 10.
Article in English | MEDLINE | ID: covidwho-1683990

ABSTRACT

Acute respiratory distress syndrome (ARDS) is triggered by various aetiological factors such as trauma, sepsis and respiratory viruses including SARS-CoV-2 and influenza A virus. Immune profiling of severe COVID-19 patients has identified a complex pattern of cytokines including granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin (IL)-5, which are significant mediators of viral-induced hyperinflammation. This strong response has prompted the development of therapies that block GM-CSF and other cytokines individually to limit inflammation related pathology. The common cytokine binding site of the human common beta (ßc) receptor signals for three inflammatory cytokines: GM-CSF, IL-5 and IL-3. In this study, ßc was targeted with the monoclonal antibody (mAb) CSL311 in engineered mice devoid of mouse ßc and ßIL-3 and expressing human ßc (hßcTg mice). Direct pulmonary administration of lipopolysaccharide (LPS) caused ARDS-like lung injury, and CSL311 markedly reduced lung inflammation and oedema, resulting in improved oxygen saturation levels in hßcTg mice. In a separate model, influenza (HKx31) lung infection caused viral pneumonia associated with a large influx of myeloid cells into the lungs of hßcTg mice. The therapeutic application of CSL311 potently decreased accumulation of monocytes/macrophages, neutrophils, and eosinophils without altering lung viral loads. Furthermore, CSL311 treatment did not limit the viral-induced expansion of NK and NKT cells, or the tissue expression of type I/II/III interferons needed for efficient viral clearance. Simultaneously blocking GM-CSF, IL-5 and IL-3 signalling with CSL311 may represent an improved and clinically applicable strategy to reducing hyperinflammation in the ARDS setting.


Subject(s)
Cytokine Receptor Common beta Subunit/genetics , Cytokine Receptor Common beta Subunit/physiology , Respiratory Distress Syndrome/immunology , Animals , Antibodies, Monoclonal/immunology , Cytokine Receptor Common beta Subunit/immunology , Cytokines , Eosinophils/immunology , Female , Humans , Immunity/genetics , Immunity/physiology , Inflammation/immunology , Leukocytes/metabolism , Male , Mice , Mice, Transgenic , Neutrophils/metabolism , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor , Receptors, Interleukin-3 , Receptors, Interleukin-5 , Respiratory Distress Syndrome/physiopathology
13.
Life Sci ; 294: 120392, 2022 Apr 01.
Article in English | MEDLINE | ID: covidwho-1670857

ABSTRACT

The SARS coronavirus 2 (SARS CoV-2) causes Coronavirus Disease (COVID-19), is an emerging viral infection. SARS CoV-2 infects target cells by attaching to Angiotensin-Converting Enzyme (ACE2). SARS CoV-2 could cause cardiac damage in patients with severe COVID-19, as ACE2 is expressed in cardiac cells, including cardiomyocytes, pericytes, and fibroblasts, and coronavirus could directly infect these cells. Cardiovascular disorders are the most frequent comorbidity found in COVID-19 patients. Immune cells such as monocytes, macrophages, and T cells may produce inflammatory cytokines and chemokines that contribute to COVID-19 pathogenesis if their functions are uncontrolled. This causes a cytokine storm in COVID-19 patients, which has been associated with cardiac damage. Tregs are a subset of immune cells that regulate immune and inflammatory responses. Tregs suppress inflammation and improve cardiovascular function through a variety of mechanisms. This is an exciting research area to explore the cellular, molecular, and immunological mechanisms related to reducing risks of cardiovascular complications in severe COVID-19. This review evaluated whether Tregs can affect COVID-19-related cardiovascular complications, as well as the mechanisms through which Tregs act.


Subject(s)
COVID-19/immunology , Cardiovascular Diseases/immunology , Cardiovascular Diseases/prevention & control , SARS-CoV-2 , T-Lymphocytes, Regulatory/physiology , Adoptive Transfer , Animals , Cardiovascular Diseases/virology , Cytokine Release Syndrome/immunology , Cytokine Release Syndrome/prevention & control , Humans , Inflammation/immunology , T-Lymphocytes, Regulatory/immunology
14.
Int J Mol Sci ; 23(3)2022 Feb 02.
Article in English | MEDLINE | ID: covidwho-1667199

ABSTRACT

The review aims to consolidate research findings on the molecular mechanisms and virulence and pathogenicity characteristics of coronavirus disease (COVID-19) causative agent, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and their relevance to four typical stages in the development of acute viral infection. These four stages are invasion; primary blockade of antiviral innate immunity; engagement of the virus's protection mechanisms against the factors of adaptive immunity; and acute, long-term complications of COVID-19. The invasion stage entails the recognition of the spike protein (S) of SARS-CoV-2 target cell receptors, namely, the main receptor (angiotensin-converting enzyme 2, ACE2), its coreceptors, and potential alternative receptors. The presence of a diverse repertoire of receptors allows SARS-CoV-2 to infect various types of cells, including those not expressing ACE2. During the second stage, the majority of the polyfunctional structural, non-structural, and extra proteins SARS-CoV-2 synthesizes in infected cells are involved in the primary blockage of antiviral innate immunity. A high degree of redundancy and systemic action characterizing these pathogenic factors allows SARS-CoV-2 to overcome antiviral mechanisms at the initial stages of invasion. The third stage includes passive and active protection of the virus from factors of adaptive immunity, overcoming of the barrier function at the focus of inflammation, and generalization of SARS-CoV-2 in the body. The fourth stage is associated with the deployment of variants of acute and long-term complications of COVID-19. SARS-CoV-2's ability to induce autoimmune and autoinflammatory pathways of tissue invasion and development of both immunosuppressive and hyperergic mechanisms of systemic inflammation is critical at this stage of infection.


Subject(s)
Adaptive Immunity , COVID-19/immunology , COVID-19/pathology , Immunity, Innate , Inflammation/immunology , Receptors, Virus/metabolism , SARS-CoV-2/immunology , COVID-19/virology , Humans , Inflammation/pathology , SARS-CoV-2/isolation & purification , SARS-CoV-2/pathogenicity
15.
Front Immunol ; 12: 780900, 2021.
Article in English | MEDLINE | ID: covidwho-1662580

ABSTRACT

Mesenchymal stem cells (MSCs) are multipotent adult stem cells present in virtually all tissues; they have potent self-renewal capacity and differentiate into multiple cell types. For many reasons, these cells are a promising therapeutic alternative to treat patients with severe COVID-19 and pulmonary post-COVID sequelae. These cells are not only essential for tissue regeneration; they can also alter the pulmonary environment through the paracrine secretion of several mediators. They can control or promote inflammation, induce other stem cells differentiation, restrain the virus load, and much more. In this work, we performed single-cell RNA-seq data analysis of MSCs in bronchoalveolar lavage samples from control individuals and COVID-19 patients with mild and severe clinical conditions. When we compared samples from mild cases with control individuals, most genes transcriptionally upregulated in COVID-19 were involved in cell proliferation. However, a new set of genes with distinct biological functions was upregulated when we compared severely affected with mild COVID-19 patients. In this analysis, the cells upregulated genes related to cell dispersion/migration and induced the γ-activated sequence (GAS) genes, probably triggered by IFNGR1 and IFNGR2. Then, IRF-1 was upregulated, one of the GAS target genes, leading to the interferon-stimulated response (ISR) and the overexpression of many signature target genes. The MSCs also upregulated genes involved in the mesenchymal-epithelial transition, virus control, cell chemotaxis, and used the cytoplasmic RNA danger sensors RIG-1, MDA5, and PKR. In a non-comparative analysis, we observed that MSCs from severe cases do not express many NF-κB upstream receptors, such as Toll-like (TLRs) TLR-3, -7, and -8; tumor necrosis factor (TNFR1 or TNFR2), RANK, CD40, and IL-1R1. Indeed, many NF-κB inhibitors were upregulated, including PPP2CB, OPTN, NFKBIA, and FHL2, suggesting that MSCs do not play a role in the "cytokine storm" observed. Therefore, lung MSCs in COVID-19 sense immune danger and act protectively in concert with the pulmonary environment, confirming their therapeutic potential in cell-based therapy for COVID-19. The transcription of MSCs senescence markers is discussed.


Subject(s)
COVID-19/immunology , Cell Proliferation/physiology , Inflammation/immunology , Lung/immunology , Mesenchymal Stem Cells/immunology , Regeneration/immunology , Adult , COVID-19/metabolism , Cell Differentiation/immunology , Cell Movement/immunology , Cytoplasm/immunology , Epithelial-Mesenchymal Transition/immunology , Humans , Inflammation/metabolism , Mesenchymal Stem Cells/metabolism , SARS-CoV-2/immunology , Up-Regulation/immunology , Young Adult
16.
Front Immunol ; 12: 747116, 2021.
Article in English | MEDLINE | ID: covidwho-1662579

ABSTRACT

The pandemic of coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 has caused a large number of deaths, and there is still no effective treatment. COVID-19 can induce a systemic inflammatory response, and its clinical manifestations are diverse. Recently, it has been reported that COVID-19 patients may develop myositis and interstitial pulmonary disease similar to dermatomyositis (DM). This condition is similar to the rapidly progressive interstitial lung disease associated with MDA5+ DM that has a poor prognosis and high mortality, and this poses a challenge for an early identification. Suppression of the immune system can protect COVID-19 patients by preventing the production of inflammatory cytokines. This article attempts to explore the possibility of a relationship between COVID-19 and DM in terms of the potential pathogenesis and clinical features and to analyze the therapeutic effect of the immunosuppressive drugs that are commonly used for the treatment of both DM and COVID-19.


Subject(s)
COVID-19/pathology , Dermatomyositis/pathology , COVID-19/immunology , Cytokines/immunology , Dermatomyositis/immunology , Humans , Immune System/immunology , Inflammation/immunology , Inflammation/pathology , Myositis/immunology , Myositis/pathology , SARS-CoV-2/immunology
17.
Commun Biol ; 5(1): 102, 2022 01 28.
Article in English | MEDLINE | ID: covidwho-1655635

ABSTRACT

Emerging studies suggest that monocytes can be trained by bacterial endotoxin to adopt distinct memory states ranging from low-grade inflammation to immune exhaustion. While low-grade inflammation may contribute to the pathogenesis of chronic diseases, exhausted monocytes with pathogenic and immune-suppressive characteristics may underlie the pathogenesis of polymicrobial sepsis including COVID-19. However, detailed processes by which the dynamic adaption of monocytes occur remain poorly understood. Here we exposed murine bone-marrow derived monocytes to chronic lipopolysaccharide (LPS) stimulation at low-dose or high-dose, as well as a PBS control. The cells were profiled for genome-wide H3K27ac modification and gene expression. The gene expression of TRAM-deficient and IRAK-M-deficient monocytes with LPS exposure was also analyzed. We discover that low-grade inflammation preferentially utilizes the TRAM-dependent pathway of TLR4 signaling, and induces the expression of interferon response genes. In contrast, high dose LPS uniquely upregulates exhaustion signatures with metabolic and proliferative pathways. The extensive differences in the epigenomic landscape between low-dose and high-dose conditions suggest the importance of epigenetic regulations in driving differential responses. Our data provide potential targets for future mechanistic or therapeutic studies.


Subject(s)
Epigenomics , Inflammation/genetics , Lipopolysaccharides/pharmacology , Monocytes/drug effects , Transcriptome , Animals , COVID-19/virology , Dose-Response Relationship, Drug , Inflammation/immunology , Lipopolysaccharides/administration & dosage , Mice , SARS-CoV-2/isolation & purification
18.
Int Immunopharmacol ; 104: 108502, 2022 03.
Article in English | MEDLINE | ID: covidwho-1641351

ABSTRACT

BACKGROUND: SARS-CoV-2 infection can lead to the abnormal induction of cytokines and a dysregulated hyperinflammatory state that is implicated in disease severity and risk of death. There are several molecules present in blood associated with immune cellular response, inflammation, and oxidative stress that could be used as severity markers in respiratory viral infections such as COVID-19. However, there is a lack of clinical studies evaluating the role of oxidative stress-related molecules including glial fibrillary acidic protein (GFAP), the receptor for advanced glycation end products (RAGE), high mobility group box-1 protein (HMGB1) and cyclo-oxygenase-2 (COX-2) in COVID-19 pathogenesis. AIM: To evaluate the role of oxidative stress-related molecules in COVID-19. METHOD: An observational study with 93 Brazilian participants from September 2020 to April 2021, comprising 23 patients with COVID-19 admitted to intensive care unit (ICU), 19 outpatients with COVID-19 with mild to moderate symptoms, 17 individuals reporting a COVID-19 history, and 34 healthy controls. Blood samples were taken from all participants and western blot assay was used to determine the RAGE, HMGB1, GFAP, and COX-2 immunocontent. RESULTS: We found that GFAP levels were higher in patients with severe or critical COVID-19 compared to outpatients (p = 0.030) and controls (p < 0.001). A significant increase in immunocontents of RAGE (p < 0.001) and HMGB1 (p < 0.001) were also found among patients admitted to the ICU compared to healthy controls, as well as an overexpression of the inducible COX-2 (p < 0.001). In addition, we found a moderate to strong correlation between RAGE, GFAP and HMGB1 proteins. CONCLUSION: SARS-CoV-2 infection induces the upregulation of GFAP, RAGE, HMGB1, and COX-2 in patients with the most severe forms of COVID-19.


Subject(s)
COVID-19/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Biomarkers/blood , COVID-19/blood , COVID-19/immunology , COVID-19/virology , Case-Control Studies , Child , Cyclooxygenase 2/blood , Cyclooxygenase 2/metabolism , Female , Glial Fibrillary Acidic Protein/blood , Glial Fibrillary Acidic Protein/metabolism , HMGB1 Protein/blood , HMGB1 Protein/metabolism , Healthy Volunteers , Humans , Inflammation/blood , Inflammation/diagnosis , Inflammation/immunology , Inflammation/virology , Male , Middle Aged , Oxidative Stress/immunology , Receptor for Advanced Glycation End Products/blood , Receptor for Advanced Glycation End Products/metabolism , SARS-CoV-2/immunology , Severity of Illness Index , Up-Regulation/immunology , Young Adult
19.
J Immunol ; 208(4): 979-990, 2022 02 15.
Article in English | MEDLINE | ID: covidwho-1631932

ABSTRACT

Calprotectin is released by activated neutrophils along with myeloperoxidase (MPO) and proteases. It plays numerous roles in inflammation and infection, and is used as an inflammatory biomarker. However, calprotectin is readily oxidized by MPO-derived hypohalous acids to form covalent dimers of its S100A8 and S100A9 subunits. The dimers are susceptible to degradation by proteases. We show that detection of human calprotectin by ELISA declines markedly because of its oxidation by hypochlorous acid and subsequent degradation. Also, proteolysis liberates specific peptides from oxidized calprotectin that is present at inflammatory sites. We identified six calprotectin-derived peptides by mass spectrometry and detected them in the bronchoalveolar lavage fluid of children with cystic fibrosis (CF). We assessed the peptides as biomarkers of neutrophilic inflammation and infection. The content of the calprotectin peptide ILVI was related to calprotectin (r = 0.72, p = 0.01, n = 10). Four of the peptides were correlated with the concentration of MPO (r > 0.7, p ≤ 0.01, n = 21), while three were higher (p < 0.05) in neutrophil elastase-positive (n = 14) than -negative samples (n = 7). Also, five of the peptides were higher (p < 0.05) in the bronchoalveolar lavage fluid from children with CF with infections (n = 21) than from non-CF children without infections (n = 6). The specific peptides liberated from calprotectin will signal uncontrolled activity of proteases and MPO during inflammation. They may prove useful in tracking inflammation in respiratory diseases dominated by neutrophils, including coronavirus disease 2019.


Subject(s)
Bronchoalveolar Lavage Fluid/immunology , Cystic Fibrosis/immunology , Inflammation/immunology , Leukocyte L1 Antigen Complex/metabolism , Neutrophils/immunology , Peptides/metabolism , Respiratory System/metabolism , Child , Child, Preschool , Cystic Fibrosis/diagnosis , Female , Humans , Inflammation/diagnosis , Leukocyte L1 Antigen Complex/genetics , Leukocyte L1 Antigen Complex/immunology , Male , Neutrophil Activation , Oxidation-Reduction , Peptides/genetics , Peptides/immunology , Proteolysis
20.
Virol J ; 18(1): 211, 2021 10 29.
Article in English | MEDLINE | ID: covidwho-1622247

ABSTRACT

BACKGROUND: The SARS-CoV-2 virus is the causing agent of the Coronavirus disease 2019 (COVID-19) characterized by a huge pro-inflammatory response and coagulation disorders that may lead to for its severe forms, in organ failure or even death. As major players of thrombo-inflammation, platelets release large amounts of immunomodulatory molecules and regulate leukocyte and endothelial activity, which are both altered in COVID-19. Altogether, this makes platelets a very likely actor of the thrombo-inflammatory complications of COVID-19. Thus, we propose to identify a platelet inflammatory signature of severe COVID-19 specifically modulated throughout the course of the disease. METHODS: Luminex technology and enzyme-linked immunosorbent assay were used to assess plasma levels of platelet inflammatory markers in patients with severe acute respiratory syndrome coronavirus 2 infection on admission and for 14 days afterwards. RESULTS: In accordance with the observations of other teams, we evidence that the plasma levels of the platelet soluble (s)CD40L is significantly elevated in the early stages of the disease. Interestingly we observe that the plasma level of sCD40L decreases overtime while that of sCD62P increases significantly. CONCLUSIONS: Our data suggest that there is a platelet signature of inflammatory response to SARS-COv-2 infection which varies overtime and could serve as monitoring biomarkers of patient inflammatory state. CLINICAL TRIAL REGISTRATION NUMBER: 2020-A01100-39; title: Human Ab Response & immunoMONItoring of COVID-19 Patients, registration date: 05/25/2020; URL of the registry: https://clinicaltrials.gov/ct2/history/NCT04373200?V_5=View .


Subject(s)
Biomarkers/blood , Blood Platelets/immunology , COVID-19 , Inflammation , Adult , Aged , COVID-19/blood , COVID-19/immunology , Female , Humans , Inflammation/blood , Inflammation/immunology , Male , Middle Aged , Young Adult
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