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1.
Antioxid Redox Signal ; 35(16): 1376-1392, 2021 12.
Article in English | MEDLINE | ID: covidwho-1342795

ABSTRACT

Significance: It is estimated that close to 50 million cases of sepsis result in over 11 million annual fatalities worldwide. The pathognomonic feature of sepsis is a dysregulated inflammatory response arising from viral, bacterial, or fungal infections. Immune recognition of pathogen-associated molecular patterns is a hallmark of the host immune defense to combat microbes and to prevent the progression to sepsis. Mitochondrial antiviral signaling protein (MAVS) is a ubiquitous adaptor protein located at the outer mitochondrial membrane, which is activated by the cytosolic pattern recognition receptors, retinoic acid-inducible gene I (RIG-I) and melanoma differentiation associated gene 5 (MDA5), following binding of viral RNA agonists. Recent Advances: Substantial progress has been made in deciphering the activation of the MAVS pathway with its interacting proteins, downstream signaling events (interferon [IFN] regulatory factors, nuclear factor kappa B), and context-dependent type I/III IFN response. Critical Issues: In the evolutionary race between pathogens and the host, viruses have developed immune evasion strategies for cleavage, degradation, or blockade of proteins in the MAVS pathway. For example, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) M protein and ORF9b protein antagonize MAVS signaling and a protective type I IFN response. Future Directions: The role of MAVS as a sensor for nonviral pathogens, host cell injury, and metabolic perturbations awaits better characterization in the future. New technical advances in multidimensional single-cell analysis and single-molecule methods will accelerate the rate of new discoveries. The ultimate goal is to manipulate MAVS activities in the form of immune-modulatory therapies to combat infections and sepsis. Antioxid. Redox Signal. 35, 1376-1392.


Subject(s)
Adaptor Proteins, Signal Transducing/immunology , Sepsis/immunology , Signal Transduction/immunology , Virus Diseases/immunology , Animals , Host-Pathogen Interactions/immunology , Humans , Immune Evasion/immunology , Sepsis/virology
2.
Int J Mol Sci ; 21(15)2020 Jul 22.
Article in English | MEDLINE | ID: covidwho-1934093

ABSTRACT

Tissue injury and inflammatory response trigger the development of fibrosis in various diseases. It has been recognized that both innate and adaptive immune cells are important players with multifaceted functions in fibrogenesis. The activated immune cells produce various cytokines, modulate the differentiation and functions of myofibroblasts via diverse molecular mechanisms, and regulate fibrotic development. The immune cells exhibit differential functions during different stages of fibrotic diseases. In this review, we summarized recent advances in understanding the roles of immune cells in regulating fibrotic development and immune-based therapies in different disorders and discuss the underlying molecular mechanisms with a focus on mTOR and JAK-STAT signaling pathways.


Subject(s)
Adaptive Immunity , Fibrosis/immunology , Immunity, Innate , Signal Transduction/immunology , Animals , B-Lymphocytes/immunology , Cytokines/metabolism , Dendritic Cells/immunology , Fibrosis/pathology , Fibrosis/therapy , Humans , Lymphopoiesis/immunology , Macrophages/immunology , Myofibroblasts/metabolism , Neutrophils/immunology , T-Lymphocytes/immunology
3.
Front Immunol ; 13: 796682, 2022.
Article in English | MEDLINE | ID: covidwho-1731771

ABSTRACT

In the ongoing coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), natural killer T (NKT) cells act as primary initiators of immune responses. However, a decrease of circulating NKT cells has been observed in COVID-19 different stages, of which the underlying mechanism remains to be elucidated. Here, by performing single-cell RNA sequencing analysis in three large cohorts of COVID-19 patients, we found that increased expression of Tim-3 promotes depletion of NKT cells during the progression stage of COVID-19, which is associated with disease severity and outcome of patients with COVID-19. Tim-3+ NKT cells also expressed high levels of CD147 and CD26, which are potential SARS-CoV-2 spike binding receptors. In the study, Tim-3+ NKT cells showed high enrichment of apoptosis, higher expression levels of mitochondrial genes and caspase genes, with a larger pseudo time value. In addition, Tim-3+ NKT cells in COVID-19 presented a stronger capacity to secrete IFN-γ, IL-4 and IL-10 compared with healthy individuals, they also demonstrated high expression of co-inhibitory receptors such as PD-1, CTLA-4, and LAG-3. Moreover, we found that IL-12 secreted by dendritic cells (DCs) was positively correlated with up-regulated expression of Tim-3 in NKT cells in COVID-19 patients. Overall, this study describes a novel mechanism by which up-regulated Tim-3 expression induced the depletion and dysfunction of NKT cells in COVID-19 patients. These findings not only have possible implications for the prediction of severity and prognosis in COVID-19 but also provide a link between NKT cells and future new therapeutic strategies in SARS-CoV-2 infection.


Subject(s)
COVID-19/immunology , Hepatitis A Virus Cellular Receptor 2/immunology , Natural Killer T-Cells/immunology , SARS-CoV-2/immunology , Humans , Interferon-gamma/immunology , Interleukin-10/immunology , Interleukin-4/immunology , Signal Transduction/immunology
4.
Cytokine ; 152: 155810, 2022 04.
Article in English | MEDLINE | ID: covidwho-1719582

ABSTRACT

Genome-wide association studies have recently identified 3p21.31, with lead variant pointing to the CXCR6 gene, as the strongest thus far reported susceptibility risk locus for severe manifestation of COVID-19. In order the determine its role, we measured plasma levels of Chemokine (C-X-C motif) ligand 16 (CXCL16) in the plasma of COVID-19 hospitalized patients. CXCL16 interacts with CXCR6 promoting chemotaxis or cell adhesion. The CXCR6/CXCL16 axis mediates homing of T cells to the lungs in disease and hyper-expression is associated with localised cellular injury. To characterize the CXCR6/CXCL16 axis in the pathogenesis of severe COVID-19, plasma concentrations of CXCL16 collected at baseline from 115 hospitalized COVID-19 patients participating in ODYSSEY COVID-19 clinical trial were assessed together with a set of controls. We report elevated levels of CXCL16 in a cohort of COVID-19 hospitalized patients. Specifically, we report significant elevation of CXCL16 plasma levels in association with severity of COVID-19 (as defined by WHO scale) (P-value < 0.02). Our current study is the largest thus far study reporting CXCL16 levels in COVID-19 hospitalized patients (with whole-genome sequencing data available). The results further support the significant role of the CXCR6/CXCL16 axis in the immunopathogenesis of severe COVID-19 and warrants further studies to understand which patients would benefit most from targeted treatments.


Subject(s)
COVID-19/blood , Chemokine CXCL16/blood , SARS-CoV-2/metabolism , Aged , COVID-19/genetics , COVID-19/immunology , Chemokine CXCL16/genetics , Chemokine CXCL16/immunology , Female , Humans , Male , Middle Aged , Patient Acuity , Receptors, CXCR6/blood , Receptors, CXCR6/genetics , Receptors, CXCR6/immunology , Signal Transduction/genetics , Signal Transduction/immunology
5.
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
6.
Cells ; 11(3)2022 01 30.
Article in English | MEDLINE | ID: covidwho-1667057

ABSTRACT

The global outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is still ongoing, as is research on the molecular mechanisms underlying cellular infection by coronaviruses, with the hope of developing therapeutic agents against this pandemic. Other important respiratory viruses such as 2009 pandemic H1N1 and H7N9 avian influenza virus (AIV), influenza A viruses, are also responsible for a possible outbreak due to their respiratory susceptibility. However, the interaction of these viruses with host cells and the regulation of post-transcriptional genes remains unclear. In this study, we detected and analyzed the comparative transcriptome profiling of SARS-CoV-2, panH1N1 (A/California/07/2009), and H7N9 (A/Shanghai/1/2013) infected cells. The results showed that the commonly upregulated genes among the three groups were mainly involved in autophagy, pertussis, and tuberculosis, which indicated that autophagy plays an important role in viral pathogenicity. There are three groups of commonly downregulated genes involved in metabolic pathways. Notably, unlike panH1N1 and H7N9, SARS-CoV-2 infection can inhibit the m-TOR pathway and activate the p53 signaling pathway, which may be responsible for unique autophagy induction and cell apoptosis. Particularly, upregulated expression of IRF1 was found in SARS-CoV-2, panH1N1, and H7N9 infection. Further analysis showed SARS-CoV-2, panH1N1, and H7N9 infection-induced upregulation of lncRNA-34087.27 could serve as a competitive endogenous RNA to stabilize IRF1 mRNA by competitively binding with miR-302b-3p. This study provides new insights into the molecular mechanisms of influenza A virus and SARS-CoV-2 infection.


Subject(s)
COVID-19/immunology , Immunity/immunology , Influenza A Virus, H1N1 Subtype/immunology , Influenza A Virus, H7N9 Subtype/immunology , Influenza, Human/immunology , RNA/immunology , Transcriptome/immunology , A549 Cells , Animals , COVID-19/genetics , COVID-19/virology , HEK293 Cells , Host-Pathogen Interactions/immunology , Humans , Immunity/genetics , Influenza A Virus, H1N1 Subtype/physiology , Influenza A Virus, H7N9 Subtype/physiology , Influenza, Human/genetics , Influenza, Human/virology , Interferon Regulatory Factor-1/genetics , Interferon Regulatory Factor-1/immunology , Interferon Regulatory Factor-1/metabolism , MicroRNAs/genetics , MicroRNAs/immunology , MicroRNAs/metabolism , Pandemics/prevention & control , RNA/genetics , RNA/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/immunology , RNA, Long Noncoding/metabolism , RNA, Messenger/genetics , RNA, Messenger/immunology , RNA, Messenger/metabolism , RNA-Seq/methods , SARS-CoV-2/physiology , Signal Transduction/genetics , Signal Transduction/immunology , Transcriptome/genetics
7.
Front Immunol ; 12: 729990, 2021.
Article in English | MEDLINE | ID: covidwho-1662578

ABSTRACT

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes the coronavirus disease 2019 (COVID-19) pandemic, represents a global crisis. Most patients developed mild/moderate symptoms, and the status of immune system varied in acute and regulatory stages. The crosstalk between immune cells and the dynamic changes of immune cell contact is rarely described. Here, we analyzed the features of immune response of paired peripheral blood mononuclear cell (PBMC) samples from the same patients during acute and regulatory stages. Consistent with previous reports, both myeloid and T cells turned less inflammatory and less activated at recovery phase. Additionally, the communication patterns of myeloid-T cell and T-B cell are obviously changed. The crosstalk analysis reveals that typical inflammatory cytokines and several chemokines are tightly correlated with the recovery of COVID-19. Intriguingly, the signal transduction of metabolic factor insulin-like growth factor 1 (IGF1) is altered at recovery phase. Furthermore, we confirmed that the serum levels of IGF1 and several inflammatory cytokines are apparently dampened after the negative conversion of SARS-CoV-2 RNA. Thus, these results reveal several potential detection and therapeutic targets that might be used for COVID-19 recovery.


Subject(s)
COVID-19/immunology , Cell Communication/immunology , Immunity/immunology , Insulin-Like Growth Factor I/immunology , B-Lymphocytes/immunology , Cytokines/immunology , Disease Progression , Humans , Leukocytes, Mononuclear/immunology , Myeloid Cells/immunology , SARS-CoV-2/immunology , Signal Transduction/immunology , T-Lymphocytes/immunology
8.
Sci Immunol ; 7(67): eabm5505, 2022 Jan 07.
Article in English | MEDLINE | ID: covidwho-1612940

ABSTRACT

Coronavirus disease 2019 (COVID-19) is a disease characterized by a profound dysregulation of the innate immune system. This knowledge has emerged from the large body of single-cell omics studies of patients with COVID-19, which have provided one of the most detailed cellular atlases of a human disease ever. However, we are only beginning to understand the innate immunological pathways that govern host defense and immunopathology in COVID-19. In this review, we discuss the emerging understanding of how SARS-CoV-2 and host-derived molecules activate specific pattern recognition receptors to elicit protective interferon responses and pathological cytokine responses, with particular focus on acute infection of the lung and lung pathophysiology in critical COVID-19. In addition, we discuss how these pathways are modulated by virus-host interactions and host stress-sensing pathways. In-depth understanding of the disease mechanisms will likely uncover specific molecular targets for the treatment of COVID-19 and other emerging viral infections. In addition, it will reveal the fine balance between beneficial protective versus pathological disease causing immune responses.


Subject(s)
COVID-19 , Immunity, Innate , Lung , SARS-CoV-2/immunology , Signal Transduction/immunology , COVID-19/immunology , COVID-19/pathology , COVID-19/physiopathology , Humans , Lung/immunology , Lung/pathology , Lung/physiopathology
9.
Signal Transduct Target Ther ; 7(1): 7, 2022 01 04.
Article in English | MEDLINE | ID: covidwho-1606287

ABSTRACT

Activation-induced cytidine deaminase (AID) initiates class-switch recombination and somatic hypermutation (SHM) in antibody genes. Protein expression and activity are tightly controlled by various mechanisms. However, it remains unknown whether a signal from the extracellular environment directly affects the AID activity in the nucleus where it works. Here, we demonstrated that a deubiquitinase USP10, which specifically stabilizes nuclear AID protein, can translocate into the nucleus after AKT-mediated phosphorylation at its T674 within the NLS domain. Interestingly, the signals from BCR and TLR1/2 synergistically promoted this phosphorylation. The deficiency of USP10 in B cells significantly decreased AID protein levels, subsequently reducing neutralizing antibody production after immunization with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or human immunodeficiency virus type 1 (HIV-1) nanoparticle vaccines. Collectively, we demonstrated that USP10 functions as an integrator for both BCR and TLR signals and directly regulates nuclear AID activity. Its manipulation could be used for the development of vaccines and adjuvants.


Subject(s)
AIDS Vaccines/immunology , B-Cell Activating Factor/immunology , COVID-19 Vaccines/immunology , Cytidine Deaminase/immunology , HIV-1/immunology , Nanoparticles , SARS-CoV-2/immunology , Signal Transduction/immunology , Ubiquitin Thiolesterase/immunology , Ubiquitination/immunology , AIDS Vaccines/genetics , Animals , B-Cell Activating Factor/genetics , COVID-19 Vaccines/genetics , Cytidine Deaminase/genetics , HEK293 Cells , HIV-1/genetics , Humans , Mice , Mice, Knockout , SARS-CoV-2/genetics , Signal Transduction/genetics , Ubiquitin Thiolesterase/genetics
10.
Front Immunol ; 12: 724936, 2021.
Article in English | MEDLINE | ID: covidwho-1592205

ABSTRACT

The COVID-19 pandemic has created an urgent situation throughout the globe. Therefore, it is necessary to identify the differentially expressed genes (DEGs) in COVID-19 patients to understand disease pathogenesis and the genetic factor(s) responsible for inter-individual variability. The DEGs will help understand the disease's potential underlying molecular mechanisms and genetic characteristics, including the regulatory genes associated with immune response elements and protective immunity. This study aimed to determine the DEGs in mild and severe COVID-19 patients versus healthy controls. The Agilent-085982 Arraystar human lncRNA V5 microarray GEO dataset (GSE164805 dataset) was used for this study. We used statistical tools to identify the DEGs. Our 15 human samples dataset was divided into three groups: mild, severe COVID-19 patients and healthy control volunteers. We compared our result with three other published gene expression studies of COVID-19 patients. Along with significant DEGs, we developed an interactome map, a protein-protein interaction (PPI) pattern, a cluster analysis of the PPI network, and pathway enrichment analysis. We also performed the same analyses with the top-ranked genes from the three other COVID-19 gene expression studies. We also identified differentially expressed lncRNA genes and constructed protein-coding DEG-lncRNA co-expression networks. We attempted to identify the regulatory genes related to immune response elements and protective immunity. We prioritized the most significant 29 protein-coding DEGs. Our analyses showed that several DEGs were involved in forming interactome maps, PPI networks, and cluster formation, similar to the results obtained using data from the protein-coding genes from other investigations. Interestingly we found six lncRNAs (TALAM1, DLEU2, and UICLM CASC18, SNHG20, and GNAS) involved in the protein-coding DEG-lncRNA network; which might be served as potential biomarkers for COVID-19 patients. We also identified three regulatory genes from our study and 44 regulatory genes from the other investigations related to immune response elements and protective immunity. We were able to map the regulatory genes associated with immune elements and identify the virogenomic responses involved in protective immunity against SARS-CoV-2 infection during COVID-19 development.


Subject(s)
COVID-19/genetics , Gene Expression Profiling/methods , Gene Expression Regulation , Immunity/genetics , Aged , COVID-19/epidemiology , COVID-19/immunology , Female , Gene Ontology , Gene Regulatory Networks , Humans , Male , Middle Aged , Pandemics/prevention & control , Protein Interaction Maps/genetics , SARS-CoV-2/immunology , SARS-CoV-2/physiology , Signal Transduction/genetics , Signal Transduction/immunology
12.
Front Immunol ; 12: 784028, 2021.
Article in English | MEDLINE | ID: covidwho-1581324

ABSTRACT

Background: Extracellular vesicles (EVs) are mediators of cell-to-cell communication in inflammatory lung diseases. They function as carriers for miRNAs which regulate mRNA transcripts and signaling pathways after uptake into recipient cells. We investigated whether miRNAs associated with circulating EVs regulate immunologic processes in COVID-19. Methods: We prospectively studied 20 symptomatic patients with COVID-19 pneumonia, 20 mechanically ventilated patients with severe COVID-19 (severe acute respiratory corona virus-2 syndrome, ARDS) and 20 healthy controls. EVs were isolated by precipitation, total RNA was extracted, profiled by small RNA sequencing and evaluated by differential gene expression analysis (DGE). Differentially regulated miRNAs between groups were bioinformatically analyzed, mRNA target transcripts identified and signaling networks constructed, thereby comparing COVID-19 pneumonia to the healthy state and pneumonia to severe COVID-19 ARDS. Results: DGE revealed 43 significantly and differentially expressed miRNAs (25 downregulated) in COVID-19 pneumonia when compared to controls, and 20 miRNAs (15 downregulated) in COVID-19 ARDS patients in comparison to those with COVID-19 pneumonia. Network analysis for comparison of COVID-19 pneumonia to healthy controls showed upregulated miR-3168 (log2FC=2.28, padjusted<0.001), among others, targeting interleukin-6 (IL6) (25.1, 15.2 - 88.2 pg/ml in COVID-19 pneumonia) and OR52N2, an olfactory smell receptor in the nasal epithelium. In contrast, miR-3168 was significantly downregulated in COVID-19 ARDS (log2FC=-2.13, padjusted=0.003) and targeted interleukin-8 (CXCL8) in a completely activated network. Toll-like receptor 4 (TLR4) was inhibited in COVID-19 pneumonia by miR-146a-5p and upregulated in ARDS by let-7e-5p. Conclusion: EV-derived miRNAs might have important regulative functions in the pathophysiology of COVID-19: CXCL8 regulates neutrophil recruitment into the lung causing epithelial damage whereas activated TLR4, to which SARS-CoV-2 spike protein binds strongly, increases cell surface ACE2 expression and destroys type II alveolar cells that secrete pulmonary surfactants; both resulting in pulmonary-capillary leakage and ARDS. These miRNAs may serve as biomarkers or as possible therapeutic targets.


Subject(s)
Biomarkers/blood , COVID-19/immunology , Extracellular Vesicles/immunology , MicroRNAs/immunology , Aged , Aged, 80 and over , COVID-19/pathology , Disease Progression , Female , Humans , Male , Middle Aged , Pneumonia/immunology , Pneumonia/pathology , SARS-CoV-2 , Signal Transduction/immunology
13.
Int J Mol Sci ; 22(24)2021 Dec 15.
Article in English | MEDLINE | ID: covidwho-1572496

ABSTRACT

In humans, over-activation of innate immunity in response to viral or bacterial infections often causes severe illness and death. Furthermore, similar mechanisms related to innate immunity can cause pathogenesis and death in sepsis, massive trauma (including surgery and burns), ischemia/reperfusion, some toxic lesions, and viral infections including COVID-19. Based on the reviewed observations, we suggest that such severe outcomes may be manifestations of a controlled suicidal strategy protecting the entire population from the spread of pathogens and from dangerous pathologies rather than an aberrant hyperstimulation of defense responses. We argue that innate immunity may be involved in the implementation of an altruistic programmed death of an organism aimed at increasing the well-being of the whole community. We discuss possible ways to suppress this atavistic program by interfering with innate immunity and suggest that combating this program should be a major goal of future medicine.


Subject(s)
Altruism , Apoptosis/immunology , Immunity, Innate/immunology , Animals , COVID-19/immunology , Cell Death/immunology , Cytokine Release Syndrome/immunology , Cytokine Release Syndrome/mortality , Humans , Inflammasomes/immunology , Inflammation/immunology , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Signal Transduction/immunology
14.
Front Immunol ; 12: 783725, 2021.
Article in English | MEDLINE | ID: covidwho-1554650

ABSTRACT

Interferons (IFNs) are cytokines that possess antiviral, antiproliferative, and immunomodulatory actions. IFN-α and IFN-ß are two major family members of type-I IFNs and are used to treat diseases, including hepatitis and multiple sclerosis. Emerging evidence suggests that type-I IFN receptors (IFNARs) are also expressed by microglia, astrocytes, and neurons in the central and peripheral nervous systems. Apart from canonical transcriptional regulations, IFN-α and IFN-ß can rapidly suppress neuronal activity and synaptic transmission via non-genomic regulation, leading to potent analgesia. IFN-γ is the only member of the type-II IFN family and induces central sensitization and microglia activation in persistent pain. We discuss how type-I and type-II IFNs regulate pain and infection via neuro-immune modulations, with special focus on neuroinflammation and neuro-glial interactions. We also highlight distinct roles of type-I IFNs in the peripheral and central nervous system. Insights into IFN signaling in nociceptors and their distinct actions in physiological vs. pathological and acute vs. chronic conditions will improve our treatments of pain after surgeries, traumas, and infections.


Subject(s)
Acute Pain/immunology , Chronic Pain/immunology , Interferon Type I/metabolism , Interferon-gamma/metabolism , /immunology , Acute Pain/pathology , Animals , Chronic Pain/pathology , Disease Models, Animal , Humans , Neuroglia/cytology , Neuroglia/immunology , Neuroglia/pathology , Nociceptors/immunology , Nociceptors/metabolism , Receptors, Interferon/metabolism , Signal Transduction/immunology , Spinal Cord/cytology , Spinal Cord/immunology , Spinal Cord/pathology
15.
Front Immunol ; 12: 756262, 2021.
Article in English | MEDLINE | ID: covidwho-1551507

ABSTRACT

A male sex bias has emerged in the COVID-19 pandemic, fitting to the sex-biased pattern in other viral infections. Males are 2.84 times more often admitted to the ICU and mortality is 1.39 times higher as a result of COVID-19. Various factors play a role in this, and novel studies suggest that the gene-dose of Toll-Like Receptor (TLR) 7 could contribute to the sex-skewed severity. TLR7 is one of the crucial pattern recognition receptors for SARS-CoV-2 ssRNA and the gene-dose effect is caused by X chromosome inactivation (XCI) escape. Female immune cells with TLR7 XCI escape have biallelic TLR7 expression and produce more type 1 interferon (IFN) upon TLR7 stimulation. In COVID-19, TLR7 in plasmacytoid dendritic cells is one of the pattern recognition receptors responsible for IFN production and a delayed IFN response has been associated with immunopathogenesis and mortality. Here, we provide a hypothesis that females may be protected to some extend against severe COVID-19, due to the biallelic TLR7 expression, allowing them to mount a stronger and more protective IFN response early after infection. Studies exploring COVID-19 treatment via the TLR7-mediated IFN pathway should consider this sex difference. Various factors such as age, sex hormones and escape modulation remain to be investigated concerning the TLR7 gene-dose effect.


Subject(s)
COVID-19/mortality , Gene Dosage/genetics , Interferon Type I/biosynthesis , Toll-Like Receptor 7/genetics , Toll-Like Receptor 7/metabolism , COVID-19/drug therapy , COVID-19/pathology , Chromosomes, Human, X/genetics , Critical Care/statistics & numerical data , Dendritic Cells/immunology , Female , Humans , Interferon Type I/immunology , Male , RNA, Viral/genetics , Receptors, Pattern Recognition/genetics , Receptors, Pattern Recognition/metabolism , Risk Factors , SARS-CoV-2/immunology , Sex Factors , Signal Transduction/immunology , X Chromosome Inactivation/genetics
16.
Front Immunol ; 12: 767319, 2021.
Article in English | MEDLINE | ID: covidwho-1538373

ABSTRACT

The importance of innate immune cells to sense and respond to their physical environment is becoming increasingly recognized. Innate immune cells (e.g. macrophages and neutrophils) are able to receive mechanical signals through several mechanisms. In this review, we discuss the role of mechanosensitive ion channels, such as Piezo1 and transient receptor potential vanilloid 4 (TRPV4), and cell adhesion molecules, such as integrins, selectins, and cadherins in biology and human disease. Furthermore, we explain that these mechanical stimuli activate intracellular signaling pathways, such as MAPK (p38, JNK), YAP/TAZ, EDN1, NF-kB, and HIF-1α, to induce protein conformation changes and modulate gene expression to drive cellular function. Understanding the mechanisms by which immune cells interpret mechanosensitive information presents potential targets to treat human disease. Important areas of future study in this area include autoimmune, allergic, infectious, and malignant conditions.


Subject(s)
Immunity, Innate/immunology , Macrophages/immunology , Mechanotransduction, Cellular/immunology , Neutrophils/immunology , Signal Transduction/immunology , Animals , Cytokines/immunology , Cytokines/metabolism , Humans , Ion Channels/immunology , Ion Channels/metabolism , Macrophages/metabolism , Neutrophils/metabolism , TRPV Cation Channels/immunology , TRPV Cation Channels/metabolism
17.
OMICS ; 25(12): 770-781, 2021 12.
Article in English | MEDLINE | ID: covidwho-1528153

ABSTRACT

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a systemic disease affecting not only the lungs but also multiple organ systems. Clinical studies implicate that SARS-CoV-2 infection causes imbalance of cellular homeostasis and immune response that trigger cytokine storm, oxidative stress, thrombosis, and insulin resistance. Mathematical modeling can offer in-depth understanding of the SARS-CoV-2 infection and illuminate how subcellular mechanisms and feedback loops underpin disease progression and multiorgan failure. We report here a mathematical model of SARS-CoV-2 infection pathway network with cytokine storm, oxidative stress, thrombosis, insulin resistance, and nitric oxide (NO) pathways. The biochemical systems theory model shows autocrine loops with positive feedback enabling excessive immune response, cytokines, transcription factors, and interferons, which can imbalance homeostasis of the system. The simulations suggest that changes in immune response led to uncontrolled release of cytokines and chemokines, including interleukin (IL)-1ß, IL-6, and tumor necrosis factor α (TNFα), and affect insulin, coagulation, and NO signaling pathways. Increased production of NETs (neutrophil extracellular traps), thrombin, PAI-1 (plasminogen activator inhibitor-1), and other procoagulant factors led to thrombosis. By analyzing complex biochemical reactions, this model forecasts the key intermediates, potential biomarkers, and risk factors at different stages of COVID-19. These insights can be useful for drug discovery and development, as well as precision treatment of multiorgan implications of COVID-19 as seen in systems medicine.


Subject(s)
COVID-19/immunology , Cytokine Release Syndrome/immunology , Insulin Resistance/immunology , Nitric Oxide/immunology , Oxidative Stress/immunology , SARS-CoV-2/immunology , Thrombosis/immunology , COVID-19/virology , Cytokine Release Syndrome/virology , Cytokines/immunology , Humans , Models, Theoretical , Signal Transduction/immunology , Thrombosis/virology
18.
Nat Immunol ; 23(1): 62-74, 2022 01.
Article in English | MEDLINE | ID: covidwho-1514418

ABSTRACT

The molecular mechanisms governing orderly shutdown and retraction of CD4+ type 1 helper T (TH1) cell responses remain poorly understood. Here we show that complement triggers contraction of TH1 responses by inducing intrinsic expression of the vitamin D (VitD) receptor and the VitD-activating enzyme CYP27B1, permitting T cells to both activate and respond to VitD. VitD then initiated the transition from pro-inflammatory interferon-γ+ TH1 cells to suppressive interleukin-10+ cells. This process was primed by dynamic changes in the epigenetic landscape of CD4+ T cells, generating super-enhancers and recruiting several transcription factors, notably c-JUN, STAT3 and BACH2, which together with VitD receptor shaped the transcriptional response to VitD. Accordingly, VitD did not induce interleukin-10 expression in cells with dysfunctional BACH2 or STAT3. Bronchoalveolar lavage fluid CD4+ T cells of patients with COVID-19 were TH1-skewed and showed de-repression of genes downregulated by VitD, from either lack of substrate (VitD deficiency) and/or abnormal regulation of this system.


Subject(s)
Interferon-gamma/immunology , Interleukin-10/immunology , SARS-CoV-2/immunology , Th1 Cells/immunology , Vitamin D/metabolism , 25-Hydroxyvitamin D3 1-alpha-Hydroxylase/metabolism , Basic-Leucine Zipper Transcription Factors/metabolism , Bronchoalveolar Lavage Fluid/cytology , COVID-19/immunology , COVID-19/pathology , Complement C3a/immunology , Complement C3b/immunology , Humans , JNK Mitogen-Activated Protein Kinases/metabolism , Lymphocyte Activation/immunology , Receptors, Calcitriol/metabolism , Respiratory Distress Syndrome/immunology , Respiratory Distress Syndrome/pathology , Respiratory Distress Syndrome/virology , STAT3 Transcription Factor/metabolism , Signal Transduction/immunology , Transcription, Genetic/genetics
19.
J Photochem Photobiol B ; 226: 112357, 2022 Jan.
Article in English | MEDLINE | ID: covidwho-1510060

ABSTRACT

Mitochondrial antiviral signaling (MAVS) protein mediates innate antiviral responses, including responses to certain coronaviruses such as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). We have previously shown that ultraviolet-A (UVA) therapy can prevent virus-induced cell death in human ciliated tracheal epithelial cells (HTEpC) infected with coronavirus-229E (CoV-229E), and results in increased intracellular levels of MAVS. In this study, we explored the mechanisms by which UVA light can activate MAVS, and whether local UVA light application can activate MAVS at locations distant from the light source (e.g. via cell-to-cell communication). MAVS levels were compared in HTEpC exposed to 2 mW/cm2 narrow band (NB)-UVA for 20 min and in unexposed controls at 30-40% and at 100% confluency, and in unexposed HTEpC treated with supernatants or lysates from UVA-exposed cells or from unexposed controls. MAVS was also assessed in different sections of confluent monolayer plates where only one section was exposed to NB-UVA. Our results showed that UVA increases the expression of MAVS protein. Further, cells in a confluent monolayer exposed to UVA conferred an elevation in MAVS in cells adjacent to the exposed section, and also in cells in the most distant sections which were not exposed to UVA. In this study, human ciliated tracheal epithelial cells exposed to UVA demonstrate increased MAVS protein, and also appear to transmit this influence to confluent cells not exposed to UVA, likely via cell-cell signaling.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/radiation effects , Ultraviolet Rays , Adaptor Proteins, Signal Transducing/immunology , COVID-19/immunology , COVID-19/radiotherapy , COVID-19/virology , Cell Communication/immunology , Cell Communication/radiation effects , Cells, Cultured , Epithelial Cells/immunology , Epithelial Cells/radiation effects , Host Microbial Interactions/immunology , Host Microbial Interactions/radiation effects , Humans , Immunity, Innate/radiation effects , Photobiology , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Signal Transduction/immunology , Signal Transduction/radiation effects , Trachea/cytology , Ultraviolet Therapy
20.
Cell Immunol ; 371: 104454, 2022 01.
Article in English | MEDLINE | ID: covidwho-1509640

ABSTRACT

Immune dysregulation is commonly observed in patients with coronavirus disease 2019 (COVID-19). Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces severe lung inflammation and innate immune cell dysregulation. However, the precise interaction between SARS-CoV-2 and the innate immune system is currently unknown. To understand the interaction between SARS-CoV-2 and natural killer (NK) cells, several SARS-CoV-2 S protein peptides capable of binding to the NKG2D receptor were screened by in silico analysis. Among them, two peptides, cov1 and cov2, bound to NK cells and NKG2D receptors. These cov peptides increased NK cytotoxicity toward lung cancer cells, stimulated interferon gamma (IFN-γ) production by NK cells, and likely mediated these responses through the phosphorylation of Vav1, a key downstream-signaling molecule of NKG2D and NK activation genes. The direct interaction between SARS-CoV-2 and NK cells is a novel finding, and modulation of this interaction has potential clinical application as a therapeutic target for COVID-19.


Subject(s)
COVID-19/immunology , Killer Cells, Natural/immunology , NK Cell Lectin-Like Receptor Subfamily K/immunology , Peptides/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Amino Acid Sequence , COVID-19/metabolism , COVID-19/virology , Cell Line, Tumor , Cytotoxicity, Immunologic/immunology , Humans , Interferon-gamma/immunology , Interferon-gamma/metabolism , Killer Cells, Natural/metabolism , Lung/immunology , Lung/pathology , Lung/virology , Lymphocyte Activation/immunology , NK Cell Lectin-Like Receptor Subfamily K/metabolism , Peptides/metabolism , Protein Binding , SARS-CoV-2/metabolism , SARS-CoV-2/physiology , Signal Transduction/immunology , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism
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