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1.
Front Immunol ; 12: 700705, 2021.
Article in English | MEDLINE | ID: covidwho-1686468

ABSTRACT

A novel coronavirus, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), arose late in 2019, with disease pathology ranging from asymptomatic to severe respiratory distress with multi-organ failure requiring mechanical ventilator support. It has been found that SARS-CoV-2 infection drives intracellular complement activation in lung cells that tracks with disease severity. However, the cellular and molecular mechanisms responsible remain unclear. To shed light on the potential mechanisms, we examined publicly available RNA-Sequencing data using CIBERSORTx and conducted a Ingenuity Pathway Analysis to address this knowledge gap. In complement to these findings, we used bioinformatics tools to analyze publicly available RNA sequencing data and found that upregulation of complement may be leading to a downregulation of T-cell activity in lungs of severe COVID-19 patients. Thus, targeting treatments aimed at the modulation of classical complement and T-cell activity may help alleviate the proinflammatory effects of COVID-19, reduce lung pathology, and increase the survival of COVID-19 patients.


Subject(s)
COVID-19/genetics , Complement Activation/genetics , Complement System Proteins/genetics , Gene Expression Profiling/methods , Lung/metabolism , T-Lymphocytes/metabolism , COVID-19/immunology , COVID-19/virology , Gene Regulatory Networks/genetics , Humans , Intracellular Space/genetics , Lung/immunology , Lung/microbiology , Lymphocyte Count , SARS-CoV-2/physiology , T-Lymphocyte Subsets/metabolism
2.
Front Immunol ; 12: 789735, 2021.
Article in English | MEDLINE | ID: covidwho-1581322

ABSTRACT

Background: The host immune response has a prominent role in the progression and outcome of SARS-CoV-2 infection. Lymphopenia has been described as an important feature of SARS-CoV-2 infection and has been associated with severe disease manifestation. Lymphocyte dysregulation and hyper-inflammation have been shown to be associated with a more severe clinical course; however, a T cell subpopulation whose dysfunction correlate with disease progression has yet to be identify. Methods: We performed an immuno-phenotypic analysis of T cell sub-populations in peripheral blood from patients affected by different severity of COVID-19 (n=60) and undergoing a different clinical evolution. Clinical severity was established based on a modified WHO score considering both ventilation support and respiratory capacity (PaO2/FiO2 ratio). The ability of circulating cells at baseline to predict the probability of clinical aggravation was explored through multivariate regression analyses. Results: The immuno-phenotypic analysis performed by multi-colour flow cytometry confirmed that patients suffering from severe COVID-19 harboured significantly reduced circulating T cell subsets, especially for CD4+ T, Th1, and regulatory T cells. Peripheral T cells also correlated with parameters associated with disease severity, i.e., PaO2/FiO2 ratio and inflammation markers. CD4+ T cell subsets showed an important significant association with clinical evolution, with patients presenting markedly decreased regulatory T cells at baseline having a significantly higher risk of aggravation. Importantly, the combination of gender and regulatory T cells allowed distinguishing between improved and worsened patients with an area under the ROC curve (AUC) of 82%. Conclusions: The present study demonstrates the association between CD4+ T cell dysregulation and COVID-19 severity and progression. Our results support the importance of analysing baseline regulatory T cell levels, since they were revealed able to predict the clinical worsening during hospitalization. Regulatory T cells assessment soon after hospital admission could thus allow a better clinical stratification and patient management.


Subject(s)
COVID-19/epidemiology , COVID-19/immunology , Hospitalization , Lymphocyte Count , SARS-CoV-2/immunology , T-Lymphocytes, Regulatory/immunology , Biomarkers , COVID-19/diagnosis , COVID-19/virology , COVID-19 Serological Testing , Cytokines/blood , Cytokines/metabolism , Disease Progression , Humans , Immunophenotyping , Inflammation Mediators/blood , Inflammation Mediators/metabolism , Prognosis , Public Health Surveillance , ROC Curve , Severity of Illness Index , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , T-Lymphocytes, Regulatory/metabolism
3.
J Infect Dis ; 224(12): 2010-2019, 2021 12 15.
Article in English | MEDLINE | ID: covidwho-1574912

ABSTRACT

BACKGROUND: Characterizing the longevity and quality of cellular immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) enhances understanding of coronavirus disease 2019 (COVID-19) immunity that influences clinical outcomes. Prior studies suggest SARS-CoV-2-specific T cells are present in peripheral blood 10 months after infection. Analysis of the function, durability, and diversity of cellular response long after natural infection, over a range of ages and disease phenotypes, is needed to identify preventative and therapeutic interventions. METHODS: We identified participants in our multisite longitudinal, prospective cohort study 12 months after SARS-CoV-2 infection representing a range of disease severity. We investigated function, phenotypes, and frequency of T cells specific for SARS-CoV-2 using intracellular cytokine staining and spectral flow cytometry, and compared magnitude of SARS-CoV-2-specific antibodies. RESULTS: SARS-CoV-2-specific antibodies and T cells were detected 12 months postinfection. Severe acute illness was associated with higher frequencies of SARS-CoV-2-specific CD4 T cells and antibodies at 12 months. In contrast, polyfunctional and cytotoxic T cells responsive to SARS-CoV-2 were identified in participants over a wide spectrum of disease severity. CONCLUSIONS: SARS-CoV-2 infection induces polyfunctional memory T cells detectable at 12 months postinfection, with higher frequency noted in those who experienced severe disease.


Subject(s)
COVID-19/immunology , COVID-19/virology , Immunologic Memory , SARS-CoV-2/immunology , T-Lymphocyte Subsets/immunology , Adult , Antibodies, Viral , Antigens, Viral , Biomarkers , COVID-19/diagnosis , COVID-19/epidemiology , Female , Humans , Immunity, Cellular , Longitudinal Studies , Male , Middle Aged , Prospective Studies , Severity of Illness Index , T-Lymphocyte Subsets/metabolism , Time Factors
4.
Viruses ; 13(11)2021 11 03.
Article in English | MEDLINE | ID: covidwho-1542790

ABSTRACT

The detailed characterization of human γδ T lymphocyte differentiation at the single-cell transcriptomic (scRNAseq) level in tumors and patients with coronavirus disease 2019 (COVID-19) requires both a reference differentiation trajectory of γδ T cells and a robust mapping method for additional γδ T lymphocytes. Here, we incepted such a method to characterize thousands of γδ T lymphocytes from (n = 95) patients with cancer or adult and pediatric COVID-19 disease. We found that cancer patients with human papillomavirus-positive head and neck squamous cell carcinoma and Epstein-Barr virus-positive Hodgkin's lymphoma have γδ tumor-infiltrating T lymphocytes that are more prone to recirculate from the tumor and avoid exhaustion. In COVID-19, both TCRVγ9 and TCRVγnon9 subsets of γδ T lymphocytes relocalize from peripheral blood mononuclear cells (PBMC) to the infected lung tissue, where their advanced differentiation, tissue residency, and exhaustion reflect T cell activation. Although severe COVID-19 disease increases both recruitment and exhaustion of γδ T lymphocytes in infected lung lesions but not blood, the anti-IL6R therapy with Tocilizumab promotes γδ T lymphocyte differentiation in patients with COVID-19. PBMC from pediatric patients with acute COVID-19 disease display similar γδ T cell lymphopenia to that seen in adult patients. However, blood γδ T cells from children with the COVID-19-related multisystem inflammatory syndrome are not lymphodepleted, but they are differentiated as in healthy PBMC. These findings suggest that some virus-induced memory γδ T lymphocytes durably persist in the blood of adults and could subsequently infiltrate and recirculate in tumors.


Subject(s)
COVID-19/immunology , Lymphocytes, Tumor-Infiltrating/immunology , Neoplasms/immunology , RNA-Seq , Receptors, Antigen, T-Cell, gamma-delta/immunology , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , Adult , Bronchoalveolar Lavage Fluid/immunology , COVID-19/complications , Cell Differentiation , Child , Head and Neck Neoplasms/immunology , Head and Neck Neoplasms/virology , Herpesvirus 4, Human/isolation & purification , Hodgkin Disease/immunology , Hodgkin Disease/virology , Humans , Lung/immunology , Lymphocyte Activation , Lymphocyte Count , Lymphocytes, Tumor-Infiltrating/metabolism , Lymphocytes, Tumor-Infiltrating/physiology , Neoplasms/virology , Papillomaviridae/isolation & purification , Severity of Illness Index , Single-Cell Analysis , Systemic Inflammatory Response Syndrome/immunology , T-Lymphocyte Subsets/physiology
5.
Viruses ; 13(11)2021 11 03.
Article in English | MEDLINE | ID: covidwho-1502529

ABSTRACT

The detailed characterization of human γδ T lymphocyte differentiation at the single-cell transcriptomic (scRNAseq) level in tumors and patients with coronavirus disease 2019 (COVID-19) requires both a reference differentiation trajectory of γδ T cells and a robust mapping method for additional γδ T lymphocytes. Here, we incepted such a method to characterize thousands of γδ T lymphocytes from (n = 95) patients with cancer or adult and pediatric COVID-19 disease. We found that cancer patients with human papillomavirus-positive head and neck squamous cell carcinoma and Epstein-Barr virus-positive Hodgkin's lymphoma have γδ tumor-infiltrating T lymphocytes that are more prone to recirculate from the tumor and avoid exhaustion. In COVID-19, both TCRVγ9 and TCRVγnon9 subsets of γδ T lymphocytes relocalize from peripheral blood mononuclear cells (PBMC) to the infected lung tissue, where their advanced differentiation, tissue residency, and exhaustion reflect T cell activation. Although severe COVID-19 disease increases both recruitment and exhaustion of γδ T lymphocytes in infected lung lesions but not blood, the anti-IL6R therapy with Tocilizumab promotes γδ T lymphocyte differentiation in patients with COVID-19. PBMC from pediatric patients with acute COVID-19 disease display similar γδ T cell lymphopenia to that seen in adult patients. However, blood γδ T cells from children with the COVID-19-related multisystem inflammatory syndrome are not lymphodepleted, but they are differentiated as in healthy PBMC. These findings suggest that some virus-induced memory γδ T lymphocytes durably persist in the blood of adults and could subsequently infiltrate and recirculate in tumors.


Subject(s)
COVID-19/immunology , Lymphocytes, Tumor-Infiltrating/immunology , Neoplasms/immunology , RNA-Seq , Receptors, Antigen, T-Cell, gamma-delta/immunology , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , Adult , Bronchoalveolar Lavage Fluid/immunology , COVID-19/complications , Cell Differentiation , Child , Head and Neck Neoplasms/immunology , Head and Neck Neoplasms/virology , Herpesvirus 4, Human/isolation & purification , Hodgkin Disease/immunology , Hodgkin Disease/virology , Humans , Lung/immunology , Lymphocyte Activation , Lymphocyte Count , Lymphocytes, Tumor-Infiltrating/metabolism , Lymphocytes, Tumor-Infiltrating/physiology , Neoplasms/virology , Papillomaviridae/isolation & purification , Severity of Illness Index , Single-Cell Analysis , Systemic Inflammatory Response Syndrome/immunology , T-Lymphocyte Subsets/physiology
6.
J Infect Dis ; 224(12): 2010-2019, 2021 12 15.
Article in English | MEDLINE | ID: covidwho-1483460

ABSTRACT

BACKGROUND: Characterizing the longevity and quality of cellular immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) enhances understanding of coronavirus disease 2019 (COVID-19) immunity that influences clinical outcomes. Prior studies suggest SARS-CoV-2-specific T cells are present in peripheral blood 10 months after infection. Analysis of the function, durability, and diversity of cellular response long after natural infection, over a range of ages and disease phenotypes, is needed to identify preventative and therapeutic interventions. METHODS: We identified participants in our multisite longitudinal, prospective cohort study 12 months after SARS-CoV-2 infection representing a range of disease severity. We investigated function, phenotypes, and frequency of T cells specific for SARS-CoV-2 using intracellular cytokine staining and spectral flow cytometry, and compared magnitude of SARS-CoV-2-specific antibodies. RESULTS: SARS-CoV-2-specific antibodies and T cells were detected 12 months postinfection. Severe acute illness was associated with higher frequencies of SARS-CoV-2-specific CD4 T cells and antibodies at 12 months. In contrast, polyfunctional and cytotoxic T cells responsive to SARS-CoV-2 were identified in participants over a wide spectrum of disease severity. CONCLUSIONS: SARS-CoV-2 infection induces polyfunctional memory T cells detectable at 12 months postinfection, with higher frequency noted in those who experienced severe disease.


Subject(s)
COVID-19/immunology , COVID-19/virology , Immunologic Memory , SARS-CoV-2/immunology , T-Lymphocyte Subsets/immunology , Adult , Antibodies, Viral , Antigens, Viral , Biomarkers , COVID-19/diagnosis , COVID-19/epidemiology , Female , Humans , Immunity, Cellular , Longitudinal Studies , Male , Middle Aged , Prospective Studies , Severity of Illness Index , T-Lymphocyte Subsets/metabolism , Time Factors
7.
J Exp Med ; 218(4)2021 04 05.
Article in English | MEDLINE | ID: covidwho-1387677

ABSTRACT

SARS-CoV-2 is responsible for an ongoing pandemic that has affected millions of individuals around the globe. To gain further understanding of the immune response in recovered individuals, we measured T cell responses in paired samples obtained an average of 1.3 and 6.1 mo after infection from 41 individuals. The data indicate that recovered individuals show persistent polyfunctional SARS-CoV-2 antigen-specific memory that could contribute to rapid recall responses. Recovered individuals also show enduring alterations in relative overall numbers of CD4+ and CD8+ memory T cells, including expression of activation/exhaustion markers, and cell division.


Subject(s)
COVID-19/immunology , COVID-19/virology , Host-Pathogen Interactions/immunology , Immunity, Cellular , SARS-CoV-2/immunology , Adult , Aged , Antigens, Viral/immunology , Biomarkers , Female , Humans , Immunophenotyping , Lymphocyte Count , Male , Middle Aged , T-Cell Antigen Receptor Specificity , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , Young Adult
8.
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
9.
Immunol Lett ; 234: 16-32, 2021 06.
Article in English | MEDLINE | ID: covidwho-1173426

ABSTRACT

Inflammasomes are cytosolic multiprotein complexes that crucially contribute to host defense against pathogens but are also involved in the pathogenesis of autoinflammatory diseases. Inflammasome formation leads to activation of effector caspases (caspase-1, 4, 5, or 11), the proteolytic maturation of IL-1ß and IL-18 as well as cleavage of the pore-forming protein Gasdermin D. Dendritic cells are major regulators of immune responses as they bridge innate and adaptive immunity. We here summarize the current knowledge on inflammasome expression and formation in murine bone marrow-, human monocyte-derived as well as murine and human primary dendritic cells. Further, we discuss both, the beneficial and detrimental, involvement of inflammasome activation in dendritic cells in cancer, infections, and autoimmune diseases. As inflammasome activation is typically accompanied by Gasdermin d-mediated pyroptosis, which is an inflammatory form of programmed cell death, inflammasome formation in dendritic cells seems ill-advised. Therefore, we propose that hyperactivation, which is inflammasome activation without the induction of pyroptosis, may be a general model of inflammasome activation in dendritic cells to enhance Th1, Th17 as well as cytotoxic T cell responses.


Subject(s)
Dendritic Cells/immunology , Dendritic Cells/metabolism , Inflammasomes/metabolism , Animals , Biomarkers , Cell Communication/genetics , Cell Communication/immunology , Cytokines/metabolism , Disease Susceptibility/immunology , Humans , Immunomodulation , Inflammation/etiology , Inflammation/metabolism , Inflammation/pathology , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism
10.
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
11.
Immunity ; 54(8): 1869-1882.e6, 2021 08 10.
Article in English | MEDLINE | ID: covidwho-1293864

ABSTRACT

Vaccine-associated enhanced respiratory disease (VAERD) was previously observed in some preclinical models of severe acute respiratory syndrome (SARS) and MERS coronavirus vaccines. We used the SARS coronavirus 2 (SARS-CoV-2) mouse-adapted, passage 10, lethal challenge virus (MA10) mouse model of acute lung injury to evaluate the immune response and potential for immunopathology in animals vaccinated with research-grade mRNA-1273. Whole-inactivated virus or heat-denatured spike protein subunit vaccines with alum designed to elicit low-potency antibodies and Th2-skewed CD4+ T cells resulted in reduced viral titers and weight loss post challenge but more severe pathological changes in the lung compared to saline-immunized animals. In contrast, a protective dose of mRNA-1273 induced favorable humoral and cellular immune responses that protected from viral replication in the upper and lower respiratory tract upon challenge. A subprotective dose of mRNA-1273 reduced viral replication and limited histopathological manifestations compared to animals given saline. Overall, our findings demonstrate an immunological signature associated with antiviral protection without disease enhancement following vaccination with mRNA-1273.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/immunology , COVID-19/prevention & control , Host-Pathogen Interactions/immunology , SARS-CoV-2/immunology , Vaccines, Synthetic/immunology , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Biopsy , COVID-19 Vaccines/administration & dosage , Disease Models, Animal , Humans , Immunoglobulin G , Immunohistochemistry , Mice , Outcome Assessment, Health Care , RNA, Messenger , Spike Glycoprotein, Coronavirus/immunology , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , Vaccines, Synthetic/administration & dosage
12.
Immunity ; 54(7): 1594-1610.e11, 2021 07 13.
Article in English | MEDLINE | ID: covidwho-1281436

ABSTRACT

COVID-19 can cause severe neurological symptoms, but the underlying pathophysiological mechanisms are unclear. Here, we interrogated the brain stems and olfactory bulbs in postmortem patients who had COVID-19 using imaging mass cytometry to understand the local immune response at a spatially resolved, high-dimensional, single-cell level and compared their immune map to non-COVID respiratory failure, multiple sclerosis, and control patients. We observed substantial immune activation in the central nervous system with pronounced neuropathology (astrocytosis, axonal damage, and blood-brain-barrier leakage) and detected viral antigen in ACE2-receptor-positive cells enriched in the vascular compartment. Microglial nodules and the perivascular compartment represented COVID-19-specific, microanatomic-immune niches with context-specific cellular interactions enriched for activated CD8+ T cells. Altered brain T-cell-microglial interactions were linked to clinical measures of systemic inflammation and disturbed hemostasis. This study identifies profound neuroinflammation with activation of innate and adaptive immune cells as correlates of COVID-19 neuropathology, with implications for potential therapeutic strategies.


Subject(s)
Brain/immunology , CD8-Positive T-Lymphocytes/immunology , COVID-19/immunology , Microglia/immunology , Blood-Brain Barrier/immunology , Blood-Brain Barrier/metabolism , Blood-Brain Barrier/pathology , Brain/metabolism , Brain/pathology , CD8-Positive T-Lymphocytes/metabolism , COVID-19/pathology , Cell Communication , Central Nervous System/immunology , Central Nervous System/metabolism , Central Nervous System/pathology , Humans , Immune Checkpoint Proteins/metabolism , Inflammation , Lymphocyte Activation , Multiple Sclerosis/immunology , Multiple Sclerosis/pathology , Olfactory Bulb/immunology , Olfactory Bulb/metabolism , Olfactory Bulb/pathology , Respiratory Insufficiency/immunology , Respiratory Insufficiency/pathology , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/metabolism , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism
13.
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
14.
Int Immunopharmacol ; 97: 107828, 2021 Aug.
Article in English | MEDLINE | ID: covidwho-1253058

ABSTRACT

In various pathological conditions, cellular immunity plays an important role in immune responses. Amongimmunecells, T lymphocytes pdomotecellular and humoralresponses as well as innate immunity. Therefore, careful investigation of these cells has a significant impact on accurate knowledge in COVID-19diseasepathogenesis. In current research, the frequency and function of various T lymphocytes involved in immune responses examined in SARS-CoV-2 patients with various disease severity compared to normal subjects. In order to make an accurate comparison among patients with various disease severity, this study was performed on asymptomatic recovered cases (n = 20), ICU hospitalized patients (n = 30), non-ICU hospitalized patients (n = 30), and normal subjects (n = 20). To precisely evaluate T cells activity following purification, their cytokine secretion activity was examined. Similarly, immediately after purification of Treg cells, their inhibitory activity on T cells was investigated. The results showed that COVID-19 patients with severe disease (ICU hospitalized patients) not only had a remarkable increase in Th1 and Th17 but also a considerable decrease in Th2 and Treg cells. More importantly, as the IL-17 and IFN-γ secretion was sharply increased in severe disease, the secretion of IL-10 and IL-4 was decreased. Furthermore, the inhibitory activity of Treg cells was reduced in severe disease patients in comparison to other groups. In severe COVID-19 disease, current findings indicate when the inflammatory arm of cellular immunity is significantly increased, a considerable reduction in anti-inflammatory and regulatory arm occurred.


Subject(s)
COVID-19/blood , COVID-19/immunology , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/virology , Adult , Aged , Cytokines/immunology , Cytokines/metabolism , Female , Healthy Volunteers , Humans , Immunity, Cellular , Inflammation/metabolism , Interferon-gamma/metabolism , Interleukin-10/metabolism , Interleukin-17/metabolism , Interleukin-4/metabolism , Leukocytes/immunology , Leukocytes/metabolism , Male , Middle Aged , Severity of Illness Index , T-Lymphocyte Subsets/metabolism , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/metabolism , Th1 Cells/immunology , Th1 Cells/metabolism , Th17 Cells/immunology , Th17 Cells/metabolism , Th2 Cells/immunology , Th2 Cells/metabolism , Young Adult
15.
Immunity ; 54(7): 1578-1593.e5, 2021 07 13.
Article in English | MEDLINE | ID: covidwho-1246000

ABSTRACT

Immune profiling of COVID-19 patients has identified numerous alterations in both innate and adaptive immunity. However, whether those changes are specific to SARS-CoV-2 or driven by a general inflammatory response shared across severely ill pneumonia patients remains unknown. Here, we compared the immune profile of severe COVID-19 with non-SARS-CoV-2 pneumonia ICU patients using longitudinal, high-dimensional single-cell spectral cytometry and algorithm-guided analysis. COVID-19 and non-SARS-CoV-2 pneumonia both showed increased emergency myelopoiesis and displayed features of adaptive immune paralysis. However, pathological immune signatures suggestive of T cell exhaustion were exclusive to COVID-19. The integration of single-cell profiling with a predicted binding capacity of SARS-CoV-2 peptides to the patients' HLA profile further linked the COVID-19 immunopathology to impaired virus recognition. Toward clinical translation, circulating NKT cell frequency was identified as a predictive biomarker for patient outcome. Our comparative immune map serves to delineate treatment strategies to interfere with the immunopathologic cascade exclusive to severe COVID-19.


Subject(s)
COVID-19/immunology , SARS-CoV-2/pathogenicity , Adult , Angiotensin-Converting Enzyme 2/metabolism , Antigen Presentation , Biomarkers/blood , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , COVID-19/pathology , Female , HLA Antigens/genetics , HLA Antigens/immunology , Humans , Immunity, Innate , Immunophenotyping , Male , Middle Aged , Natural Killer T-Cells/immunology , Pneumonia/immunology , Pneumonia/pathology , SARS-CoV-2/immunology , Severity of Illness Index , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism
16.
Front Immunol ; 12: 645741, 2021.
Article in English | MEDLINE | ID: covidwho-1190313

ABSTRACT

Particulate matter (PM) induces neutrophilic inflammation and deteriorates the prognosis of diseases such as cardiovascular diseases, cancers, and infections, including COVID-19. Here, we addressed the role of γδ T cells and intestinal microbiome in PM-induced acute neutrophilia. γδ T cells are a heterogeneous population composed of Tγδ1, Tγδ2, Tγδ17, and naïve γδ T cells (TγδN) and commensal bacteria promote local expansion of Tγδ17 cells, particularly in the lung and gut without affecting their Vγ repertoire. Tγδ17 cells are more tissue resident than Tγδ1 cells, while TγδN cells are circulating cells. IL-1R expression in Tγδ17 cells is highest in the lung and they outnumber all the other type 17 cells such as Th17, ILC3, NKT17, and MAIT17 cells. Upon PM exposure, IL-1ß-secreting neutrophils and IL-17-producing Tγδ17 cells attract each other around the airways. Accordingly, PM-induced neutrophilia was significantly relieved in γδ T- or IL-17-deficient and germ-free mice. Collectively, these findings show that the commensal microbiome promotes PM-induced neutrophilia in the lung via Tγδ17 cells.


Subject(s)
Leukocytosis/etiology , Lung/immunology , Microbiota , Neutrophils/pathology , Particulate Matter/adverse effects , Receptors, Antigen, T-Cell, gamma-delta/metabolism , Th17 Cells/immunology , Th17 Cells/metabolism , Animals , Asthma/etiology , Asthma/metabolism , Asthma/pathology , Biomarkers , Cytokines/metabolism , Disease Models, Animal , Disease Susceptibility , Fluorescent Antibody Technique , Immunity, Innate , Immunophenotyping , Leukocytosis/metabolism , Leukocytosis/pathology , Lung/metabolism , Lung/pathology , Mice , Neutrophils/metabolism , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism
17.
Front Immunol ; 12: 636118, 2021.
Article in English | MEDLINE | ID: covidwho-1190312

ABSTRACT

Following respiratory viral infections or local immunizations, lung resident-memory T cells (TRM) of the CD8 lineage provide protection against the same pathogen or related pathogens with cross-reactive T cell epitopes. Yet, it is now clear that, if homeostatic controls are lost following viral pneumonia, CD8 TRM cells can mediate pulmonary pathology. We recently showed that the aging process can result in loss of homeostatic controls on CD8 TRM cells in the respiratory tract. This may be germane to treatment modalities in both influenza and coronavirus disease 2019 (COVID-19) patients, particularly, the portion that present with symptoms linked to long-lasting lung dysfunction. Here, we review the developmental cues and functionalities of CD8 TRM cells in viral pneumonia models with a particular focus on their capacity to mediate heterogeneous responses of immunity and pathology depending on immune status.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , COVID-19/immunology , COVID-19/virology , Immunologic Memory , Lung/immunology , Lung/virology , SARS-CoV-2/immunology , Age Factors , Animals , Biomarkers , CD8-Positive T-Lymphocytes/metabolism , COVID-19/metabolism , COVID-19/pathology , Disease Resistance/immunology , Homeostasis , Host-Pathogen Interactions/immunology , Humans , Immunophenotyping , Lung/metabolism , Lung/pathology , Lymphocyte Count , Pulmonary Fibrosis/etiology , Pulmonary Fibrosis/metabolism , Pulmonary Fibrosis/pathology , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , T-Lymphocyte Subsets/pathology
18.
Front Immunol ; 12: 626308, 2021.
Article in English | MEDLINE | ID: covidwho-1190310

ABSTRACT

We have previously shown that conformational change in the ß2-integrin is a very early activation marker that can be detected with fluorescent multimers of its ligand intercellular adhesion molecule (ICAM)-1 for rapid assessment of antigen-specific CD8+ T cells. In this study, we describe a modified protocol of this assay for sensitive detection of functional antigen-specific CD4+ T cells using a monoclonal antibody (clone m24 Ab) specific for the open, high-affinity conformation of the ß2-integrin. The kinetics of ß2-integrin activation was different on CD4+ and CD8+ T cells (several hours vs. few minutes, respectively); however, m24 Ab readily stained both cell types 4-6 h after antigen stimulation. With this protocol, we were able to monitor ex vivo effector and memory CD4+ and CD8+ T cells specific for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), cytomegalovirus (CMV), Epstein-Barr virus (EBV), and hepatitis B virus (HBV) in whole blood or cryopreserved peripheral blood mononuclear cells (PBMCs) of infected or vaccinated individuals. By costaining ß2-integrin with m24 and CD154 Abs, we assessed extremely low frequencies of polyfunctional CD4+ T cell responses. The novel assay used in this study allows very sensitive and simultaneous screening of both CD4+ and CD8+ T cell reactivities, with versatile applicability in clinical and vaccination studies.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Host-Pathogen Interactions/immunology , Integrins/metabolism , Adult , Aged , Amino Acid Sequence , Binding Sites , COVID-19/genetics , COVID-19/immunology , COVID-19/metabolism , COVID-19/virology , Carrier Proteins/chemistry , Cytokines/metabolism , Cytomegalovirus/immunology , Epitopes, T-Lymphocyte/chemistry , Epitopes, T-Lymphocyte/immunology , Female , HLA Antigens/chemistry , HLA Antigens/immunology , Host-Pathogen Interactions/genetics , Humans , Immunohistochemistry , Immunophenotyping , Integrins/genetics , Intercellular Adhesion Molecule-1/chemistry , Intercellular Adhesion Molecule-1/metabolism , Lymphocyte Activation/immunology , Male , Middle Aged , Protein Binding , Protein Multimerization , SARS-CoV-2/immunology , T-Cell Antigen Receptor Specificity , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism
19.
Front Immunol ; 12: 666983, 2021.
Article in English | MEDLINE | ID: covidwho-1186803

ABSTRACT

The emergence of viruses with pandemic potential such as the SARS-CoV-2 coronavirus causing COVID-19 poses a global health challenge. There is remarkable progress in vaccine technology in response to this threat, but their design often overlooks the innate arm of immunity. Gamma Delta (γδ) T cells are a subset of T cells with unique features that gives them a key role in the innate immune response to a variety of homeostatic alterations, from cancer to microbial infections. In the context of viral infection, a growing body of evidence shows that γδ T cells are particularly equipped for early virus detection, which triggers their subsequent activation, expansion and the fast deployment of antiviral functions such as direct cytotoxic pathways, secretion of cytokines, recruitment and activation of other immune cells and mobilization of a trained immunity memory program. As such, γδ T cells represent an attractive target to stimulate for a rapid and effective resolution of viral infections. Here, we review the known aspects of γδ T cells that make them crucial component of the immune response to viruses, and the ways that their antiviral potential can be harnessed to prevent or treat viral infection.


Subject(s)
COVID-19/immunology , COVID-19/virology , Host-Pathogen Interactions , Receptors, Antigen, T-Cell, gamma-delta/metabolism , SARS-CoV-2/immunology , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , Adaptive Immunity , Animals , COVID-19/drug therapy , Combined Modality Therapy , Cytotoxicity, Immunologic , Disease Management , Disease Susceptibility/immunology , Host-Pathogen Interactions/immunology , Humans , Immunity, Innate , Receptors, Immunologic/metabolism
20.
J Infect Dis ; 224(1): 70-80, 2021 07 02.
Article in English | MEDLINE | ID: covidwho-1169671

ABSTRACT

Herein we measured CD4+ T-cell responses against common cold coronaviruses (CCC) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in high-risk health care workers (HCW) and community controls. We observed higher levels of CCC-reactive T cells in SARS-CoV-2-seronegative HCW compared to community donors, consistent with potential higher occupational exposure of HCW to CCC. We further show that SARS-CoV-2 T-cell reactivity of seronegative HCW was higher than community controls and correlation between CCC and SARS-CoV-2 responses is consistent with cross-reactivity and not associated with recent in vivo activation. Surprisingly, CCC T-cell reactivity was decreased in SARS-CoV-2-infected HCW, suggesting that exposure to SARS-CoV-2 might interfere with CCC responses, either directly or indirectly. This result was unexpected, but consistently detected in independent cohorts derived from Miami and San Diego. CD4+ T-cell responses against common cold coronaviruses (CCC) are elevated in SARS-CoV-2 seronegative high-risk health care workers (HCW) compared to COVID-19 convalescent HCW, suggesting that exposure to SARS-CoV-2 might interfere with CCC responses and/or cross-reactivity associated with a protective effect.


Subject(s)
COVID-19/epidemiology , COVID-19/immunology , Health Personnel , SARS-CoV-2/immunology , T-Lymphocyte Subsets/immunology , Adult , Antibodies, Viral , Biomarkers , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , COVID-19/diagnosis , COVID-19/virology , Enzyme-Linked Immunosorbent Assay , Epitopes, T-Lymphocyte/chemistry , Epitopes, T-Lymphocyte/immunology , Female , Humans , Immunophenotyping , Lymphocyte Activation/immunology , Male , Middle Aged , Peptides/chemistry , Peptides/immunology , Public Health Surveillance , Seroepidemiologic Studies , Severity of Illness Index , Spike Glycoprotein, Coronavirus/immunology , T-Lymphocyte Subsets/metabolism
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