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1.
Viruses ; 14(6)2022 06 10.
Article in English | MEDLINE | ID: covidwho-1911619

ABSTRACT

Here, we longitudinally assessed the ex vivo frequency and phenotype of SARS-CoV-2 membrane protein (aa145-164) epitope-specific CD4+ T-cells of an anti-CD20-treated patient with prolonged viral positivity in direct comparison to an immunocompetent patient through an MHC class II DRB1*11:01 Tetramer analysis. We detected a high and stable SARS-CoV-2 membrane-specific CD4+ T-cell response in both patients, with higher frequencies of virus-specific CD4+ T-cells in the B-cell-depleted patient. However, we found an altered virus-specific CD4+ T-cell memory phenotype in the B-cell-depleted patient that was skewed towards late differentiated memory T-cells, as well as reduced frequencies of SARS-CoV-2-specific CD4+ T-cells with CD45RA- CXCR5+ PD-1+ circulating T follicular helper cell (cTFH) phenotype. Furthermore, we observed a delayed contraction of CD127- virus-specific effector cells. The expression of the co-inhibitory receptors TIGIT and LAG-3 fluctuated on the virus-specific CD4+ T-cells of the patient, but were associated with the inflammation markers IL-6 and CRP. Our findings indicate that, despite B-cell depletion and a lack of B-cell-T-cell interaction, a robust virus-specific CD4+ T-cell response can be primed that helps to control the viral replication, but which is not sufficient to fully abrogate the infection.


Subject(s)
COVID-19 , SARS-CoV-2 , CD4-Positive T-Lymphocytes , Humans , Phenotype , T-Lymphocytes, Helper-Inducer
2.
Eur J Immunol ; 52(8): 1297-1307, 2022 Aug.
Article in English | MEDLINE | ID: covidwho-1782587

ABSTRACT

COVID-19, caused by SARS-CoV-2, has emerged as a global pandemic. While immune responses of the adaptive immune system have been in the focus of research, the role of NK cells in COVID-19 remains less well understood. Here, we characterized NK cell-mediated SARS-CoV-2 antibody-dependent cellular cytotoxicity (ADCC) against SARS-CoV-2 spike-1 (S1) and nucleocapsid (NC) protein. Serum samples from SARS-CoV-2 resolvers induced significant CD107a-expression by NK cells in response to S1 and NC, while serum samples from SARS-CoV-2-negative individuals did not. Furthermore, serum samples from individuals that received the BNT162b2 vaccine induced strong CD107a expression by NK cells that increased with the second vaccination and was significantly higher than observed in infected individuals. As expected, vaccine-induced responses were only directed against S1 and not against NC protein. S1-specific CD107a responses by NK cells were significantly correlated to NK cell-mediated killing of S1-expressing cells. Interestingly, screening of serum samples collected prior to the COVID-19 pandemic identified two individuals with cross-reactive antibodies against SARS-CoV-2 S1, which also induced degranulation of NK cells. Taken together, these data demonstrate that antibodies induced by SARS-CoV-2 infection and anti-SARS-CoV-2 vaccines can trigger significant NK cell-mediated ADCC activity, and identify some cross-reactive ADCC-activity against SARS-CoV-2 by endemic coronavirus-specific antibodies.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Viral/metabolism , Antibody-Dependent Cell Cytotoxicity , BNT162 Vaccine , Humans , Killer Cells, Natural , Pandemics
3.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-320952

ABSTRACT

BACKGROUND Male sex was repeatedly identified as a risk factor for death and intensive care admission. However, it is yet unclear whether sex hormones are associated with disease severity in COVID-19 patients. We sought to characterize sex differences in hormone levels and cytokine responses in critically ill COVID-19 patients. METHODS We performed a retrospective cohort study of critically ill COVID-19 patients. Males and females were compared. Multivariate regression was performed to assess the association between sex hormones, cytokine responses and the requirement for extracorporeal membrane oxygenation (ECMO) treatment. RESULTS We analyzed sex hormone levels (estradiol and testosterone) of n =181 male and female individuals. These consisted of n =50 critically ill COVID-19 patients ( n =39 males, n =11 females), n =42 critically ill non-COVID-19 patients ( n =27 males, n =15 females), n =39 non-COVID-19 patients with coronary heart diseases (CHD) ( n =25 males, n =14 females) and n =50 healthy individuals ( n =30 males, n =20 females). We detected highest estradiol levels in critically ill male COVID-19 patients compared to non-COVID-19 patients ( p =0.0123), patients with CHD ( p =0.0002) or healthy individuals ( p =0.0007). Lowest testosterone levels were detected in critically ill male COVID-19 patients compared to non-COVID-19 patients ( p =0.0094), patients with CHD ( p =0.0068) or healthy individuals ( p <0.0001). No statistically significant differences in sex hormone levels were detected in critically ill female COVID-19 patients, albeit similar trends in estradiol levels were observed. In critically ill male COVID-19 patients, cytokine and chemokine responses (IFN-γ, p =0.0301;IL-1RA, p =0.0160;IL-6, p =0.0145;MCP-1, p =0.0052;MIP-1α, p =0.0134) were significantly elevated in those with higher Sequential Organ Failure Assessment (SOFA) scores (8-11). Linear regression analysis revealed that herein IFN-γ levels correlate with estradiol levels in male and female COVID-19 patients (R 2 =0.216, =0.0009). Male COVID-19 patients with elevated estradiol levels were more likely to receive ECMO treatment in the course of their ICU stay ( p =0.0009). CONCLUSIONS We identified high estradiol and low testosterone levels as a hallmark of critically ill male COVID-19 patients. Elevated estradiol levels in critically ill male COVID-19 patients were positively associated with IFN-γ levels and increased risk for ECMO requirement.

5.
Clin Infect Dis ; 73(11): e4020-e4024, 2021 12 06.
Article in English | MEDLINE | ID: covidwho-1560662

ABSTRACT

We provide detailed clinical, virological, and immunological data of a B-cell-depleted patient treated with obinutuzumab for follicular lymphoma with protracted coronavirus disease 2019 (COVID-19) and viremia. A sustained response was achieved after 2 courses of remdesivir and subsequent convalescent plasma therapy. Immunocompromised patients might require combined and prolonged antiviral treatment regimens.


Subject(s)
COVID-19 , Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , COVID-19/drug therapy , COVID-19/therapy , Humans , Immunization, Passive , SARS-CoV-2
6.
PLoS Pathog ; 17(9): e1009842, 2021 09.
Article in English | MEDLINE | ID: covidwho-1416911

ABSTRACT

The aim of this study was to define the breadth and specificity of dominant SARS-CoV-2-specific T cell epitopes using a comprehensive set of 135 overlapping 15-mer peptides covering the SARS-CoV-2 envelope (E), membrane (M) and nucleoprotein (N) in a cohort of 34 individuals with acute (n = 10) and resolved (n = 24) COVID-19. Following short-term virus-specific in vitro cultivation, the single peptide-specific CD4+ T cell response of each patient was screened using enzyme linked immuno spot assay (ELISpot) and confirmed by single-peptide intracellular cytokine staining (ICS) for interferon-γ (IFN-γ) production. 97% (n = 33) of patients elicited one or more N, M or E-specific CD4+ T cell responses and each patient targeted on average 21.7 (range 0-79) peptide specificities. Overall, we identified 10 N, M or E-specific peptides that showed a response frequency of more than 36% and five of them showed high binding affinity to multiple HLA class II binders in subsequent in vitro HLA binding assays. Three peptides elicited CD4+ T cell responses in more than 55% of all patients, namely Mem_P30 (aa146-160), Mem_P36 (aa176-190), both located within the M protein, and Ncl_P18 (aa86-100) located within the N protein. These peptides were further defined in terms of length and HLA restriction. Based on this epitope and restriction data we developed a novel DRB*11 tetramer (Mem_aa145-164) and examined the ex vivo phenotype of SARS-CoV-2-specific CD4+ T cells in one patient. This detailed characterization of single T cell peptide responses demonstrates that SARS-CoV-2 infection universally primes a broad T cell response directed against multiple specificities located within the N, M and E structural protein.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , COVID-19/immunology , SARS-CoV-2/immunology , Acute Disease , Adult , Aged , Cohort Studies , Coronavirus Envelope Proteins/immunology , Coronavirus Nucleocapsid Proteins/immunology , Enzyme-Linked Immunospot Assay , Epitopes, T-Lymphocyte/immunology , Female , Humans , Male , Middle Aged , Phosphoproteins/immunology , Spike Glycoprotein, Coronavirus/immunology , Survivors , T-Cell Antigen Receptor Specificity , Viral Matrix Proteins/immunology
7.
Emerg Microbes Infect ; 10(1): 1807-1818, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1360311

ABSTRACT

Male sex was repeatedly identified as a risk factor for death and intensive care admission. However, it is yet unclear whether sex hormones are associated with disease severity in COVID-19 patients. In this study, we analysed sex hormone levels (estradiol and testosterone) of male and female COVID-19 patients (n = 50) admitted to an intensive care unit (ICU) in comparison to control non-COVID-19 patients at the ICU (n = 42), non-COVID-19 patients with the most prevalent comorbidity (coronary heart diseases) present within the COVID-19 cohort (n = 39) and healthy individuals (n = 50). We detected significantly elevated estradiol levels in critically ill male COVID-19 patients compared to all control cohorts. Testosterone levels were significantly reduced in critically ill male COVID-19 patients compared to control cohorts. No statistically significant differences in sex hormone levels were detected in critically ill female COVID-19 patients, albeit similar trends towards elevated estradiol levels were observed. Linear regression analysis revealed that among a broad range of cytokines and chemokines analysed, IFN-γ levels are positively associated with estradiol levels in male and female COVID-19 patients. Furthermore, male COVID-19 patients with elevated estradiol levels were more likely to receive ECMO treatment. Thus, we herein identified that disturbance of sex hormone metabolism might present a hallmark in critically ill male COVID-19 patients.


Subject(s)
COVID-19/mortality , COVID-19/pathology , Estradiol/blood , Testosterone/blood , Aged , Aged, 80 and over , COVID-19/blood , Critical Care , Critical Illness , Extracorporeal Membrane Oxygenation , Female , Humans , Hypogonadism/pathology , Intensive Care Units , Interferon-gamma/blood , Male , Middle Aged , Retrospective Studies , Risk Factors , SARS-CoV-2 , Severity of Illness Index , Sex Distribution
9.
Clin Infect Dis ; 73(11): e4020-e4024, 2021 12 06.
Article in English | MEDLINE | ID: covidwho-889500

ABSTRACT

We provide detailed clinical, virological, and immunological data of a B-cell-depleted patient treated with obinutuzumab for follicular lymphoma with protracted coronavirus disease 2019 (COVID-19) and viremia. A sustained response was achieved after 2 courses of remdesivir and subsequent convalescent plasma therapy. Immunocompromised patients might require combined and prolonged antiviral treatment regimens.


Subject(s)
COVID-19 , Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , COVID-19/drug therapy , COVID-19/therapy , Humans , Immunization, Passive , SARS-CoV-2
10.
J Clin Virol ; 130: 104549, 2020 09.
Article in English | MEDLINE | ID: covidwho-650882

ABSTRACT

BACKGROUND: The global market for SARS-CoV-2-immunoassays is becoming ever more crowded with antibody-tests of various formats, targets and technologies, careful evaluation is crucial for understanding the implications of individual test results. Here, we evaluate the clinical performance of five automated immunoassays on a set of clinical samples. METHODS: Serum/plasma samples of 75 confirmed COVID-19 patients and 320 pre-pandemic serum samples of healthy blood donors were subjected to two IgG and three total antibody SARS-CoV-2-immunoassays. All test setups were automated workflows. RESULTS: Positivity of assays (onset of symptoms > 10 days) ranged between 68.4 % and 81.6 % (Diasorin 68.4 %, Euroimmun 70.3 %, Siemens 73.7 %, Roche 79.0 % and Wantai 81.6 %). All examined assays demonstrated high specificity of >99 % (Euroimmun, Diasorin: 99.1 %, Wantai: 99.4 %) but only two reached levels above 99.5 % (Roche: 99.7 %, Siemens 100 %). Interestingly, there was no overlap in false positive results between the assays. The strongest correlation of quantitative results was observed between the Diasorin and Euroimmun IgG tests (r2 = 0.76). Overall, we observed no difference in the distribution of test results between female and male patients (p-values: 0.18-0.87). A significant difference between severely versus critically ill patients was demonstrated for the Euroimmun, Diasorin, Wantai and Siemens assays (p-values:0.041). CONCLUSION: All assays showed good clinical performance. Our data confirm that orthogonal test strategies as recommended by the CDC can enhance clinical specificity. However, the suboptimal rates of test positivity found at time of hospitalization in this cohort underline the importance of molecular diagnostics to rule out/confirm active infection with SARS-CoV-2.


Subject(s)
Antibodies, Viral/blood , Coronavirus Infections/diagnosis , Pneumonia, Viral/diagnosis , Serologic Tests/methods , Adolescent , Adult , Aged , Aged, 80 and over , Automation, Laboratory , Betacoronavirus , COVID-19 , COVID-19 Testing , Clinical Laboratory Techniques , Cohort Studies , Coronavirus Infections/immunology , False Positive Reactions , Female , Hospitalization/statistics & numerical data , Humans , Immunoglobulin G/blood , Male , Middle Aged , Pandemics , Pneumonia, Viral/immunology , SARS-CoV-2 , Sensitivity and Specificity , Young Adult
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