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1.
Front Immunol ; 13: 939899, 2022.
Article in English | MEDLINE | ID: covidwho-2022717

ABSTRACT

A majority of patients with sepsis surviving the first days in intensive care units (ICU) enter a state of immunosuppression contributing to their worsening. A novel virotherapy based on the non-propagative Modified Virus Ankara (MVA) expressing the human interleukin-7 (hIL-7) cytokine fused to an Fc fragment, MVA-hIL-7-Fc, was developed and shown to enhance innate and adaptive immunity and confer survival advantages in murine sepsis models. Here, we assessed the capacity of hIL-7-Fc produced by the MVA-hIL-7-Fc to improve ex vivo T lymphocyte functions from ICU patients with sepsis. Primary hepatocytes were transduced with the MVA-hIL-7-Fc or an empty MVA, and cell supernatants containing the secreted hIL-7-Fc were harvested for in vitro and ex vivo studies. Whole blood from ICU patients [septic shock = 15, coronavirus disease 2019 (COVID-19) = 30] and healthy donors (n = 36) was collected. STAT5 phosphorylation, cytokine production, and cell proliferation were assessed upon T cell receptor (TCR) stimulation in presence of MVA-hIL-7-Fc-infected cell supernatants. Cells infected by MVA-hIL-7-Fc produced a dimeric, glycosylated, and biologically active hIL-7-Fc. Cell supernatants containing the expressed hIL-7-Fc triggered the IL-7 pathway in T lymphocytes as evidenced by the increased STAT5 phosphorylation in CD3+ cells from patients and healthy donors. The secreted hIL-7-Fc improved Interferon-γ (IFN-γ) and/or Tumor necrosis factor-α (TNF-α) productions and CD4+ and CD8+ T lymphocyte proliferation after TCR stimulation in patients with bacterial and viral sepsis. This study demonstrates the capacity of the novel MVA-hIL-7-Fc-based virotherapy to restore ex vivo T cells immune functions in ICU patients with sepsis and COVID-19, further supporting its clinical development.


Subject(s)
COVID-19 , Sepsis , Shock, Septic , Animals , COVID-19/therapy , Critical Illness , Cytokines/metabolism , Humans , Interleukin-7/metabolism , Mice , Receptors, Antigen, T-Cell/metabolism , STAT5 Transcription Factor/metabolism , Sepsis/therapy
3.
Ann Biol Clin (Paris) ; 80(2): 190-198, 2022 Mar 01.
Article in French | MEDLINE | ID: covidwho-1928339

ABSTRACT

INTRODUCTION: Le niveau d'expression des molécules HLA-DR à la surface des monocytes (mHLA-DR) est un marqueur diagnostique utilisé pour évaluer l'immunité des patients en réanimation (choc septique, polytraumatisés, brulures, greffe et plus récemment Covid-19). Il est également utilisé comme un outil de stratification dans les essais cliniques utilisant des thérapies immunostimulantes chez ces patients. L'objectif de cette étude était d'évaluer les performances analytiques d'une méthode de cytométrie en flux pour mesurer mHLA-DR afin de répondre aux exigences de la norme NF EN ISO 15189 dans le cadre de l'accréditation des laboratoires de biologie médicale. Matériels et méthodes. L'évaluation (performances de la technique, étendue de la mesure, comparaison de méthode) a été menée en suivant le SH GTA 04, guide recommandé par le Comité français d'accréditation (COFRAC). En complément, certaines conditions pré analytiques ont été ré-évaluées. Résultats. L'ensemble des coefficients de variation évaluant les performances étaient inférieurs à 10 % (répétabilité, reproductibilité, variabilité interopérateur). Les limites de quantification et de linéarité étaient adaptées à l'utilisation clinique du paramètre. Les résultats étaient identiques quel que soit le type et le fournisseur de cytomètre en flux. Les contraintes de conservation pré-analytiques des échantillons ont été confirmées. CONCLUSION: Les résultats étaient conformes aux exigences de qualité recommandées par le COFRAC. Ils permettent l'accréditation de la mesure de mHLA-DR par cytométrie en flux et son utilisation en soins courants.


Subject(s)
COVID-19 , HLA-DR Antigens , Monocytes , Flow Cytometry , HLA-DR Antigens/biosynthesis , HLA-DR Antigens/immunology , Humans , Monocytes/immunology , Monocytes/metabolism
5.
Annals of Intensive Care ; 12(1), 2022.
Article in English | ProQuest Central | ID: covidwho-1837129

ABSTRACT

BackgroundLymphopenia is a hallmark of severe coronavirus disease 19 (COVID-19). Similar alterations have been described in bacterial sepsis and therapeutic strategies targeting T cell function such as recombinant human interleukin 7 (rhIL-7) have been proposed in this clinical context. As COVID-19 is a viral sepsis, the objectives of this study were to characterize T lymphocyte response over time in severe COVID-19 patients and to assess the effect of ex vivo administration of rhIL-7.ResultsPeripheral blood mononuclear cells from COVID-19 patients hospitalized in intensive care unit (ICU) were collected at admission and after 20 days. Transcriptomic profile was evaluated through NanoString technology. Inhibitory immune checkpoints expressions were determined by flow cytometry. T lymphocyte proliferation and IFN-γ production were evaluated after ex vivo stimulation in the presence or not of rhIL-7. COVID-19 ICU patients were markedly lymphopenic at admission. Mononuclear cells presented with inhibited transcriptomic profile prevalently with impaired T cell activation pathways. CD4 + and CD8 + T cells presented with over-expression of co-inhibitory molecules PD-1, PD-L1, CTLA-4 and TIM-3. CD4 + and CD8 + T cell proliferation and IFN-γ production were markedly altered in samples collected at ICU admission. These alterations, characteristic of a T cell exhaustion state, were more pronounced at ICU admission and alleviated over time. Treatment with rhIL-7 ex vivo significantly improved both T cell proliferation and IFN-γ production in cells from COVID-19 patients.ConclusionsSevere COVID-19 patients present with features of profound T cell exhaustion upon ICU admission which can be reversed ex vivo by rhIL-7. These results reinforce our understanding of severe COVID-19 pathophysiology and opens novel therapeutic avenues to treat such critically ill patients based of immunomodulation approaches. Defining the appropriate timing for initiating such immune-adjuvant therapy in clinical setting and the pertinent markers for a careful selection of patients are now warranted to confirm the ex vivo results described so far.Trial registration ClinicalTrials.gov identifier: NCT04392401 Registered 18 May 2020, http:// clinicaltrials.gov/ct2/show/NCT04392401.

6.
EBioMedicine ; 78: 103967, 2022 Apr.
Article in English | MEDLINE | ID: covidwho-1757276

ABSTRACT

BACKGROUND: In critically ill COVID-19 patients, the initial response to SARS-CoV-2 infection is characterized by major immune dysfunctions. The capacity of these severe patients to mount a robust and persistent SARS-CoV-2 specific T cell response despite the presence of severe immune alterations during the ICU stay is unknown. METHODS: Critically ill COVID-19 patients were sampled five times during the ICU stay and 9 and 13 months afterwards. Immune monitoring included counts of lymphocyte subpopulations, HLA-DR expression on monocytes, plasma IL-6 and IL-10 concentrations, anti-SARS-CoV-2 IgG levels and T cell proliferation in response to three SARS-CoV-2 antigens. FINDINGS: Despite the presence of major lymphopenia and decreased monocyte HLA-DR expression during the ICU stay, convalescent critically ill COVID-19 patients consistently generated adaptive and humoral immune responses against SARS-CoV-2 maintained for more than one year after hospital discharge. Patients with long hospital stays presented with stronger anti-SARS-CoV-2 specific T cell response but no difference in anti-SARS-CoV2 IgG levels. INTERPRETATION: Convalescent critically ill COVID-19 patients consistently generated a memory immune response against SARS-CoV-2 maintained for more than one year after hospital discharge. In recovered individuals, the intensity of SARS-CoV-2 specific T cell response was dependent on length of hospital stay. FUNDING: This observational study was supported by funds from the Hospices Civils de Lyon, Fondation HCL, Claude Bernard Lyon 1 University and Région Auvergne Rhône-Alpes and by partial funding by REACTing (Research and ACTion targeting emerging infectious diseases) INSERM, France and a donation from Fondation AnBer (http://fondationanber.fr/).


Subject(s)
COVID-19 , Immunologic Memory , T-Lymphocytes , Antibodies, Viral/blood , COVID-19/immunology , Critical Illness , HLA-DR Antigens , Humans , Immunoglobulin G/blood , SARS-CoV-2 , T-Lymphocytes/immunology
7.
Arch Med Res ; 52(8): 850-857, 2021 11.
Article in English | MEDLINE | ID: covidwho-1631298

ABSTRACT

BACKGROUND: As COVID-19 pandemic and vaccination effects progress, research now focuses on adaptive immunological response to SARS-CoV-2. Few studies specifically investigated intensive care unit (ICU) patients, and little is known about kinetics of humoral response in such critically ill patients. In this context, the main objective of the present work was to perform a longitudinal analysis of the humoral response in critically ill COVID-19 patients with prolonged ICU stays in regard with initial inflammatory response, disease severity and mortality. METHODS: Over a 3 week period, circulating immunoglobulins (Ig) against SARS-CoV-2 along with several immunological and clinical parameters were measured in 64 ICU COVID-19 patients. RESULTS: Critically ill COVID-19 patients mounted a dynamic and sustained antibody response of both IgM and IgG as soon as the first day of ICU hospitalization. This serological response was not associated with any of the classical immunological parameters measured at ICU admission or with initial severity clinical scores. IgM and IgG levels and seroconversion trajectories were not associated with unfavourable outcome. CONCLUSION: Despite rapid seroconversion and elevated humoral response, COVID-19 patients are still characterized by elevated mortality. Additional studies, including cytotoxic T cell functions, are mandatory to understand the immunological mechanisms contributing to long stay of COVID-19 patients in ICU.


Subject(s)
COVID-19 , Critical Illness , Humans , Intensive Care Units , Pandemics , SARS-CoV-2 , Seroconversion
9.
J Leukoc Biol ; 111(2): 489-496, 2022 02.
Article in English | MEDLINE | ID: covidwho-1293207

ABSTRACT

Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of immature myeloid cells with immunosuppressive properties. In cancer patients, the expression of lectin-type oxidized LDL receptor 1 (LOX-1) on granulocytic MDSC identifies a subset of MDSC that retains the most potent immunosuppressive properties. The main objective of the present work was to explore the presence of LOX-1+ MDSC in bacterial and viral sepsis. To this end, whole blood LOX-1+ cells were phenotypically, morphologically, and functionally characterized. They were monitored in 39 coronavirus disease-19 (COVID-19, viral sepsis) and 48 septic shock (bacterial sepsis) patients longitudinally sampled five times over a 3 wk period in intensive care units (ICUs). The phenotype, morphology, and immunosuppressive functions of LOX-1+ cells demonstrated that they were polymorphonuclear MDSC. In patients, we observed the significant emergence of LOX-1+ MDSC in both groups. The peak of LOX-1+ MDSC was 1 wk delayed with respect to ICU admission. In COVID-19, their elevation was more pronounced in patients with acute respiratory distress syndrome. The persistence of these cells may contribute to long lasting immunosuppression leaving the patient unable to efficiently resolve infections.


Subject(s)
COVID-19/immunology , Leukocytes, Mononuclear/immunology , Myeloid-Derived Suppressor Cells/immunology , Respiratory Distress Syndrome/physiopathology , SARS-CoV-2/immunology , Scavenger Receptors, Class E/metabolism , Shock, Septic/immunology , Aged , COVID-19/metabolism , COVID-19/pathology , COVID-19/virology , Female , Humans , Male , Middle Aged , Shock, Septic/metabolism , Shock, Septic/microbiology , Shock, Septic/pathology
10.
Crit Care ; 25(1): 140, 2021 04 12.
Article in English | MEDLINE | ID: covidwho-1181117

ABSTRACT

BACKGROUND: Since the onset of the pandemic, only few studies focused on longitudinal immune monitoring in critically ill COVID-19 patients with acute respiratory distress syndrome (ARDS) whereas their hospital stay may last for several weeks. Consequently, the question of whether immune parameters may drive or associate with delayed unfavorable outcome in these critically ill patients remains unsolved. METHODS: We present a dynamic description of immuno-inflammatory derangements in 64 critically ill COVID-19 patients including plasma IFNα2 levels and IFN-stimulated genes (ISG) score measurements. RESULTS: ARDS patients presented with persistently decreased lymphocyte count and mHLA-DR expression and increased cytokine levels. Type-I IFN response was initially induced with elevation of IFNα2 levels and ISG score followed by a rapid decrease over time. Survivors and non-survivors presented with apparent common immune responses over the first 3 weeks after ICU admission mixing gradual return to normal values of cellular markers and progressive decrease of cytokines levels including IFNα2. Only plasma TNF-α presented with a slow increase over time and higher values in non-survivors compared with survivors. This paralleled with an extremely high occurrence of secondary infections in COVID-19 patients with ARDS. CONCLUSIONS: Occurrence of ARDS in response to SARS-CoV2 infection appears to be strongly associated with the intensity of immune alterations upon ICU admission of COVID-19 patients. In these critically ill patients, immune profile presents with similarities with the delayed step of immunosuppression described in bacterial sepsis.


Subject(s)
COVID-19/blood , Critical Illness , Intensive Care Units/trends , Interferon-alpha/blood , Respiratory Distress Syndrome/blood , Adult , Aged , Biomarkers/blood , COVID-19/epidemiology , COVID-19/immunology , Critical Illness/epidemiology , Female , Hospitalization/trends , Humans , Immunity/immunology , Longitudinal Studies , Male , Middle Aged , Respiratory Distress Syndrome/epidemiology , Respiratory Distress Syndrome/immunology
11.
Cytometry A ; 99(5): 466-471, 2021 05.
Article in English | MEDLINE | ID: covidwho-1064342

ABSTRACT

During the second surge of COVID-19 in France (fall 2020), we assessed the expression of monocyte CD169 (i.e., Siglec-1, one of the numerous IFN-stimulated genes) upon admission to intensive care units of 45 patients with RT-PCR-confirmed SARS-CoV2 pulmonary infection. Overall, CD169 expression was strongly induced on circulating monocytes of COVID-19 patients compared with healthy donors and patients with bacterial sepsis. Beyond its contribution at the emergency department, CD169 testing may be also helpful for patients' triage at the ICU to rapidly reinforce suspicion of COVID-19 etiology in patients with acute respiratory failure awaiting for PCR results for definitive diagnosis.


Subject(s)
COVID-19/blood , Intensive Care Units , Monocytes/metabolism , Patient Admission , SARS-CoV-2/pathogenicity , Sialic Acid Binding Ig-like Lectin 1/blood , Adult , Aged , Biomarkers/blood , COVID-19/diagnosis , COVID-19/immunology , COVID-19/virology , Female , Flow Cytometry , Host-Pathogen Interactions , Humans , Male , Middle Aged , Monocytes/immunology , Monocytes/virology , Predictive Value of Tests , Preliminary Data , Prognosis , Prospective Studies , SARS-CoV-2/immunology , Up-Regulation
12.
Anaesth Crit Care Pain Med ; 39(3): 395-415, 2020 06.
Article in English | MEDLINE | ID: covidwho-549176

ABSTRACT

OBJECTIVES: The world is currently facing an unprecedented healthcare crisis caused by the COVID-19 pandemic. The objective of these guidelines is to produce a framework to facilitate the partial and gradual resumption of intervention activity in the context of the COVID-19 pandemic. METHODS: The group has endeavoured to produce a minimum number of recommendations to highlight the strengths to be retained in the 7 predefined areas: (1) protection of staff and patients; (2) benefit/risk and patient information; (3) preoperative assessment and decision on intervention; (4) modalities of the preanaesthesia consultation; (5) specificity of anaesthesia and analgesia; (6) dedicated circuits and (7) containment exit type of interventions. RESULTS: The SFAR Guideline panel provides 51 statements on anaesthesia management in the context of COVID-19 pandemic. After one round of discussion and various amendments, a strong agreement was reached for 100% of the recommendations and algorithms. CONCLUSION: We present suggestions for how the risk of transmission by and to anaesthetists can be minimised and how personal protective equipment policies relate to COVID-19 pandemic context.


Subject(s)
Analgesia/standards , Anesthesia/standards , Betacoronavirus , Coronavirus Infections , Infection Control/standards , Pandemics , Pneumonia, Viral , Adult , Airway Management , Analgesia/adverse effects , Analgesia/methods , Anesthesia/adverse effects , Anesthesia/methods , COVID-19 , COVID-19 Testing , Child , Clinical Laboratory Techniques , Comorbidity , Coronavirus Infections/diagnosis , Coronavirus Infections/prevention & control , Coronavirus Infections/transmission , Critical Pathways , Cross Infection/prevention & control , Cross Infection/transmission , Disinfection , Elective Surgical Procedures , Equipment Contamination/prevention & control , Health Services Accessibility , Humans , Infection Control/methods , Informed Consent , Occupational Diseases/prevention & control , Operating Rooms/standards , Pandemics/prevention & control , Patient Isolation , Personal Protective Equipment/supply & distribution , Pneumonia, Viral/prevention & control , Pneumonia, Viral/transmission , Preoperative Care , Professional Staff Committees , Risk , SARS-CoV-2 , Symptom Assessment , Universal Precautions
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