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1.
Scand J Work Environ Health ; 49(3): 222-230, 2023 04 01.
Article in English | MEDLINE | ID: covidwho-2292454

ABSTRACT

OBJECTIVES: This study aimed to investigate (i) the main effects of office design and access to telework from home (TWFH) on self-certified sickness absence and (ii) the moderating effects of access to TWFH on the relationship between office design and self-certified sickness absence. METHODS: The study used cross-sectional survey data from a nationally representative sample from Norway (N=4329). Research objectives were investigated with negative binomial hurdle models, adjusting for age, gender, education level, leadership responsibility, and time spent on office work. Moderating effects of TWFH were evaluated with pairwise comparisons and plots of estimated marginal means. RESULTS: In adjusted models, employees in conventional open-plan offices [odds ratio (OR) 1.32, 95% confidence interval (CI) 1.13-1.54] had significantly higher odds of sickness absence than employees in private offices. Employees with access to TWFH (OR 0.86, 95% CI 0.74-0.99) had significantly lower odds of sickness absence than employees with no access. Among employees with access to TWFH, those in conventional open-plan offices had significantly higher predicted probability of self-certified sickness absence than those in private offices (z=4.41, P<0.0001). There were no significant differences between office designs among employees who did not have access to TWFH. There were no significant main or moderating effects on the number of sickness absence episodes in adjusted models. CONCLUSIONS: The current study identifies conventional open-plan offices as a potential risk factor for sickness absence. While access to TWFH may be a protective factor overall, it amplified - rather than attenuated - differences in sickness absence between employees in private offices and conventional open-plan offices.


Subject(s)
Sick Leave , Teleworking , Humans , Cross-Sectional Studies , Risk Factors , Educational Status , Surveys and Questionnaires
2.
Lancet Microbe ; 4(3): e140-e148, 2023 03.
Article in English | MEDLINE | ID: covidwho-2184914

ABSTRACT

BACKGROUND: Capsid virus-like particles (cVLP) have proven safe and immunogenic and can be a versatile platform to counter pandemics. We aimed to clinically test a modular cVLP COVID-19 vaccine in individuals who were naive to SARS-CoV-2. METHODS: In this phase 1, single-centre, dose-escalation, adjuvant-selection, open-label clinical trial, we recruited participants at the Radboud University Medical Center in Nijmegen, Netherlands, and sequentially assigned them to seven groups. Eligible participants were healthy, aged 18-55 years, and tested negative for SARS-CoV-2 and anti-SARS-CoV-2 antibodies. Participants were vaccinated intramuscularly on days 0 and 28 with 6 µg, 12 µg, 25 µg, 50 µg, or 70 µg of the cVLP-based COVID-19 vaccine (ABNCoV2). A subgroup received MF59-adjuvanted ABNCoV2. Follow-up was for 24 weeks after second vaccination. The primary objectives were to assess the safety and tolerability of ABNCoV2 and to identify a dose that optimises the tolerability-immunogenicity ratio 14 days after the first vaccination. The primary safety endpoint was the number of related grade 3 adverse events and serious adverse events in the intention-to-treat population. The primary immunogenicity endpoint was the concentration of ABNCoV2-specific antibodies. The trial is registered with ClinicalTrials.gov, NCT04839146. FINDINGS: 45 participants (six to nine per group) were enrolled between March 15 and July 15, 2021. Participants had a total of 249 at least possibly related solicited adverse events (185 grade 1, 63 grade 2, and one grade 3) within a week after vaccination. Two serious adverse events occurred; one was classified as a possible adverse reaction. Antibody titres were dose-dependent with levels plateauing at a vaccination dose of 25-70 µg ABNCoV2. After second vaccination, live virus neutralisation activity against major SARS-CoV-2 variants was high but was lower with an omicron (BA.1) variant. Vaccine-specific IFNγ+ CD4+ T cells were induced. INTERPRETATION: Immunisation with ABNCoV2 was well tolerated, safe, and resulted in a functional immune response. The data support the need for additional clinical development of ABNCoV2 as a second-generation SARS-CoV-2 vaccine. The modular cVLP platform will accelerate vaccine development, beyond SARS-CoV-2. FUNDING: EU, Carlsberg Foundation, and the Novo Nordisk Foundation.


Subject(s)
COVID-19 , Viral Vaccines , Humans , Adjuvants, Immunologic , Capsid , Capsid Proteins , COVID-19 Vaccines , SARS-CoV-2 , Viral Vaccines/adverse effects
3.
Cell Rep ; 42(1): 111995, 2023 01 31.
Article in English | MEDLINE | ID: covidwho-2177162

ABSTRACT

The emergence of SARS-CoV-2 variants of concern (VOC) is driven by mutations that mediate escape from neutralizing antibodies. There is also evidence that mutations can cause loss of T cell epitopes. However, studies on viral escape from T cell immunity have been hampered by uncertain estimates of epitope prevalence. Here, we map and quantify CD8 T cell responses to SARS-CoV-2-specific minimal epitopes in blood drawn from April to June 2020 from 83 COVID-19 convalescents. Among 37 HLA ligands eluted from five prevalent alleles and an additional 86 predicted binders, we identify 29 epitopes with an immunoprevalence ranging from 3% to 100% among individuals expressing the relevant HLA allele. Mutations in VOC are reported in 10.3% of the epitopes, while 20.6% of the non-immunogenic peptides are mutated in VOC. The nine most prevalent epitopes are conserved in VOC. Thus, comprehensive mapping of epitope prevalence does not provide evidence that mutations in VOC are driven by escape of T cell immunity.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , CD8-Positive T-Lymphocytes , COVID-19/immunology , Epitopes, T-Lymphocyte/genetics , Immunodominant Epitopes/genetics , SARS-CoV-2/genetics
4.
Int Immunopharmacol ; 112: 109283, 2022 Nov.
Article in English | MEDLINE | ID: covidwho-2105145

ABSTRACT

BACKGROUND: Coronavirus disease 2019 (COVID-19) continues to be a major global public health challenge, with the emergence of variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Current vaccines or monoclonal antibodies may not well be protect against infection with new SARS-CoV-2 variants. Unlike antibody-based treatment, T cell-based therapies such as TCR-T cells can target epitopes that are highly conserved across different SARS-CoV-2 variants. Reportedly, T cell-based immunity alone can restrict SARS-CoV-2 replication. METHODS: In this study, we identified two TCRs targeting the RNA-dependent RNA polymerase (RdRp) protein in CD8 + T cells. Functional evaluation by transducing these TCRs into CD8 + or CD4 + T cells confirmed their specificity. RESULTS: Combinations of inflammatory and anti-inflammatory cytokines secreted by CD8 + and CD4 + T cells can help control COVID-19 in patients. Moreover, the targeted epitope is highly conserved in all emerged SARS-CoV-2 variants, including the Omicron. It is also conserved in the seven coronaviruses that infect humans and more broadly in the subfamily Coronavirinae. CONCLUSIONS: The pan-genera coverage of mutant epitopes from the Coronavirinae subfamily by the two TCRs highlights the unique strengths of TCR-T cell therapies in controlling the ongoing pandemic and in preparing for the next coronavirus outbreak.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , COVID-19/therapy , Epitopes , Receptors, Antigen, T-Cell/genetics , Antibodies, Monoclonal/therapeutic use , RNA-Dependent RNA Polymerase , Cytokines , Epitopes, T-Lymphocyte/genetics
5.
Front Bioinform ; 1: 622992, 2021.
Article in English | MEDLINE | ID: covidwho-2089804

ABSTRACT

Predictive models for vaccine design have become a powerful and necessary resource for the expeditiousness design of vaccines to combat the ongoing SARS-CoV-2 global pandemic. Here we use the power of these predicted models to assess the sequence diversity of circulating SARS-CoV-2 proteomes in the context of an individual's CD8 T-cell immune repertoire to identify potential. defined regions of immunogenicity. Using this approach of expedited and rational CD8 T-cell vaccine design, it may be possible to develop a therapeutic vaccine candidate with the potential for both global and local coverage.

6.
International immunopharmacology ; 2022.
Article in English | EuropePMC | ID: covidwho-2046068

ABSTRACT

Background Coronavirus disease 2019 (COVID-19) continues to be a major global public health challenge, with the emergence of variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Current vaccines or monoclonal antibodies may not well be protect against infection with new SARS-CoV-2 variants. Unlike antibody-based treatment, T cell-based therapies such as TCR-T cells can target epitopes that are highly conserved across different SARS-CoV-2 variants. Reportedly, T cell-based immunity alone can restrict SARS-CoV-2 replication. Methods In this study, we identified two TCRs targeting the RNA-dependent RNA polymerase (RdRp) protein in CD8+ T cells. Functional evaluation by transducing these TCRs into CD8+ or CD4+ T cells confirmed their specificity. Results Combinations of inflammatory and anti-inflammatory cytokines secreted by CD8+ and CD4+ T cells can help control COVID-19 in patients. Moreover, the targeted epitope is highly conserved in all emerged SARS-CoV-2 variants, including the Omicron. It is also conserved in the seven coronaviruses that infect humans and more broadly in the subfamily Coronavirinae. Conclusions The pan-genera coverage of mutant epitopes from the Coronavirinae subfamily by the two TCRs highlights the unique strengths of TCR-T cell therapies in controlling the ongoing pandemic and in preparing for the next coronavirus outbreak.

8.
Front Immunol ; 13: 857440, 2022.
Article in English | MEDLINE | ID: covidwho-1817942

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a worldwide pandemic. Here, we present non-human primate immunogenicity and protective efficacy data generated with the capsid virus-like particle (cVLP)-based vaccine ABNCoV2 that has previously demonstrated immunogenicity in mice. In rhesus macaques, a single vaccination with either 15 or 100 µg ABNCoV2 induced binding and neutralizing antibodies in a dose-dependent manner, at levels comparable to those measured in human convalescents. A second vaccine administration led to a >50-fold increase in neutralizing antibodies, with 2-log higher mean levels in the 100-µg ABNCoV2 group compared with convalescent samples. Upon SARS-CoV-2 challenge, a significant reduction in viral load was observed for both vaccine groups relative to the challenge control group, with no evidence of enhanced disease. Remarkably, neutralizing antibody titers against an original SARS-CoV-2 isolate and against variants of concern were comparable, indicating a potential for broad protection afforded by ABNCoV2, which is currently in clinical testing.


Subject(s)
COVID-19 , Viral Vaccines , Animals , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , Capsid , Capsid Proteins , Humans , Macaca mulatta , SARS-CoV-2
9.
Virus Evol ; 8(1): veac023, 2022.
Article in English | MEDLINE | ID: covidwho-1795112

ABSTRACT

COG-UK Mutation Explorer (COG-UK-ME, https://sars2.cvr.gla.ac.uk/cog-uk/-last accessed date 16 March 2022) is a web resource that displays knowledge and analyses on SARS-CoV-2 virus genome mutations and variants circulating in the UK, with a focus on the observed amino acid replacements that have an antigenic role in the context of the human humoral and cellular immune response. This analysis is based on more than 2 million genome sequences (as of March 2022) for UK SARS-CoV-2 data held in the CLIMB-COVID centralised data environment. COG-UK-ME curates these data and displays analyses that are cross-referenced to experimental data collated from the primary literature. The aim is to track mutations of immunological importance that are accumulating in current variants of concern and variants of interest that could alter the neutralising activity of monoclonal antibodies (mAbs), convalescent sera, and vaccines. Changes in epitopes recognised by T cells, including those where reduced T cell binding has been demonstrated, are reported. Mutations that have been shown to confer SARS-CoV-2 resistance to antiviral drugs are also included. Using visualisation tools, COG-UK-ME also allows users to identify the emergence of variants carrying mutations that could decrease the neutralising activity of both mAbs present in therapeutic cocktails, e.g. Ronapreve. COG-UK-ME tracks changes in the frequency of combinations of mutations and brings together the curated literature on the impact of those mutations on various functional aspects of the virus and therapeutics. Given the unpredictable nature of SARS-CoV-2 as exemplified by yet another variant of concern, Omicron, continued surveillance of SARS-CoV-2 remains imperative to monitor virus evolution linked to the efficacy of therapeutics.

10.
Front Public Health ; 9: 708260, 2021.
Article in English | MEDLINE | ID: covidwho-1775825

ABSTRACT

The psychosocial work environment is of great importance for regaining health and productivity after a workplace disaster. Still, there is a lack of knowledge about the impact of a disaster on the psychosocial work environment. The purpose of this study was to examine whether employees' perceptions of role clarity, role conflicts, and predictability in their work situation changed from before to after a workplace terrorist attack. We combined data from two prospective work environment surveys of employees in three governmental ministries that were the target of the 2011 Oslo terrorist attack. A first two-wave survey was conducted 4-5 years and 2-3 years before the attack, and a second three-wave survey took place 10 months, 2 years, and 3 years after the attack. Of 504 individuals who were employed at the time of the bombing, 220 were employed in both pre- and post-disaster periods, participated in both the first and the second survey, and consented to the linking of data from the two surveys. We found no significant changes in levels of role clarity, role conflict, and predictability from before to after the terrorist attack. Adjusting for sex, age and education had no effect on the results. The findings suggest that perceptions of the psychosocial working environment are likely to be maintained at previous levels in the aftermath of a workplace disaster. Considering the importance of the psychosocial work environment for regaining health and productivity, the findings are important for the preparation for, and management of, future crises.


Subject(s)
Terrorism , Workplace , Disasters , Humans , Longitudinal Studies , Prospective Studies , Terrorism/psychology
11.
iScience ; 25(2): 103850, 2022 Feb 18.
Article in English | MEDLINE | ID: covidwho-1665031

ABSTRACT

Many steps of the MHC class I antigen processing pathway can be predicted using computational methods. Here we show that epitope predictions can be further improved by considering abundance levels of peptides' source proteins. We utilized biophysical principles and existing MHC binding prediction tools in concert with abundance estimates of source proteins to derive a function that estimates the likelihood of a peptide to be an MHC class I ligand. We found that this combination improved predictions for both naturally eluted ligands and cancer neoantigen epitopes. We compared the use of different measures of antigen abundance, including mRNA expression by RNA-Seq, gene translation by Ribo-Seq, and protein abundance by proteomics on a dataset of SARS-CoV-2 epitopes. Epitope predictions were improved above binding predictions alone in all cases and gave the highest performance when using proteomic data. Our results highlight the value of incorporating antigen abundance levels to improve epitope predictions.

12.
mBio ; 12(5): e0181321, 2021 10 26.
Article in English | MEDLINE | ID: covidwho-1462901

ABSTRACT

Vaccines pave the way out of the SARS-CoV-2 pandemic. Besides mRNA and adenoviral vector vaccines, effective protein-based vaccines are needed for immunization against current and emerging variants. We have developed a virus-like particle (VLP)-based vaccine using the baculovirus-insect cell expression system, a robust production platform known for its scalability, low cost, and safety. Baculoviruses were constructed encoding SARS-CoV-2 spike proteins: full-length S, stabilized secreted S, or the S1 domain. Since subunit S only partially protected mice from SARS-CoV-2 challenge, we produced S1 for conjugation to bacteriophage AP205 VLP nanoparticles using tag/catcher technology. The S1 yield in an insect-cell bioreactor was ∼11 mg/liter, and authentic protein folding, efficient glycosylation, partial trimerization, and ACE2 receptor binding was confirmed. Prime-boost immunization of mice with 0.5 µg S1-VLPs showed potent neutralizing antibody responses against Wuhan and UK/B.1.1.7 SARS-CoV-2 variants. This two-component nanoparticle vaccine can now be further developed to help alleviate the burden of COVID-19. IMPORTANCE Vaccination is essential to reduce disease severity and limit the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Protein-based vaccines are useful to vaccinate the world population and to boost immunity against emerging variants. Their safety profiles, production costs, and vaccine storage temperatures are advantageous compared to mRNA and adenovirus vector vaccines. Here, we use the versatile and scalable baculovirus expression vector system to generate a two-component nanoparticle vaccine to induce potent neutralizing antibody responses against SARS-CoV-2 variants. These nanoparticle vaccines can be quickly adapted as boosters by simply updating the antigen component.


Subject(s)
Antibodies, Neutralizing/metabolism , Nanoparticles/metabolism , SARS-CoV-2/metabolism , Animals , COVID-19/immunology , Female , Glycosylation , Mice , Mice, Inbred BALB C , SARS-CoV-2/immunology , Sf9 Cells , Viral Vaccines/immunology
13.
J Infect Dis ; 224(6): 956-966, 2021 09 17.
Article in English | MEDLINE | ID: covidwho-1429243

ABSTRACT

BACKGROUND: Coronavirus disease 2019 (COVID-19) continues to be a major public health challenge globally. The identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-derived T-cell epitopes is of critical importance for peptide vaccines or diagnostic tools of COVID-19. METHODS: In this study, several SARS-CoV-2-derived human leukocyte antigen (HLA)-I binding peptides were predicted by NetMHCpan-4.1 and selected by Popcover to achieve pancoverage of the Chinese population. The top 5 ranked peptides derived from each protein of SARS-CoV-2 were then evaluated using peripheral blood mononuclear cells from unexposed individuals (negative for SARS-CoV-2 immunoglobulin G). RESULTS: Seven epitopes derived from 4 SARS-CoV-2 proteins were identified. It is interesting to note that most (5 of 7) of the SARS-CoV-2-derived peptides with predicted affinities for HLA-I molecules were identified as HLA-II-restricted epitopes and induced CD4+ T cell-dependent responses. These results complete missing pieces of pre-existing SARS-CoV-2-specific T cells and suggest that pre-existing T cells targeting all SARS-CoV-2-encoded proteins can be discovered in unexposed populations. CONCLUSIONS: In summary, in the current study, we present an alternative and effective strategy for the identification of T-cell epitopes of SARS-CoV-2 in healthy subjects, which may indicate an important role in the development of peptide vaccines for COVID-19.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/immunology , COVID-19/prevention & control , Epitopes, T-Lymphocyte/immunology , Vaccines, Subunit/immunology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Cell Line , Humans , Leukocytes, Mononuclear/immunology , SARS-CoV-2
14.
Addict Behav Rep ; 14: 100377, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1415151

ABSTRACT

Working at home has become a frequent work arrangement following the COVID-19 pandemic. However, little is known about how working at home influence alcohol use among employees. This study examines associations between working at home at least 15 h per week and alcohol consumption using data from a pre-COVID-19 sample. Self-reported questionnaire data on working at home and alcohol use from a large cross-sectional sample of Norwegian employees (N = 14,728). Data were collected between 2004 and 2019 and were analyzed by ordinal logistic regressions. Working at home for >15 h per week was significantly associated with alcohol use (OR 1.67, 95% CI: 1.30 - 2.16). The association remained significant after adjusting for age, gender, leadership position, and educational level. Working at home may facilitate alcohol use that otherwise would not happen. Organizations must ensure that policies and procedures are in place to prevent alcohol use during working hours among employees working at home.

15.
Front Immunol ; 12: 728936, 2021.
Article in English | MEDLINE | ID: covidwho-1413272

ABSTRACT

The use of minimal peptide sets offers an appealing alternative for design of vaccines and T cell diagnostics compared to conventional whole protein approaches. T cell immunogenicity towards peptides is contingent on binding to human leukocyte antigen (HLA) molecules of the given individual. HLA is highly polymorphic, and each variant typically presents a different repertoire of peptides. This polymorphism combined with pathogen diversity challenges the rational selection of peptide sets with broad immunogenic potential and population coverage. Here we propose PopCover-2.0, a simple yet highly effective method, for resolving this challenge. The method takes as input a set of (predicted) CD8 and/or CD4 T cell epitopes with associated HLA restriction and pathogen strain annotation together with information on HLA allele frequencies, and identifies peptide sets with optimal pathogen and HLA (class I and II) coverage. PopCover-2.0 was benchmarked on historic data in the context of HIV and SARS-CoV-2. Further, the immunogenicity of the selected SARS-CoV-2 peptides was confirmed by experimentally validating the peptide pools for T cell responses in a panel of SARS-CoV-2 infected individuals. In summary, PopCover-2.0 is an effective method for rational selection of peptide subsets with broad HLA and pathogen coverage. The tool is available at https://services.healthtech.dtu.dk/service.php?PopCover-2.0.


Subject(s)
Epitopes, T-Lymphocyte/immunology , HLA Antigens/genetics , HLA Antigens/immunology , Peptides/immunology , Alleles , Allergy and Immunology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , COVID-19/immunology , COVID-19/prevention & control , Genotype , HLA Antigens/classification , Humans , Immunogenicity, Vaccine , Immunologic Techniques , Peptides/classification , SARS-CoV-2/immunology
16.
Front Immunol ; 11: 1836, 2020.
Article in English | MEDLINE | ID: covidwho-1389162

ABSTRACT

Examining CD8+ and CD4+ T cell responses after primary Yellow Fever vaccination in a cohort of 210 volunteers, we have identified and tetramer-validated 92 CD8+ and 50 CD4+ T cell epitopes, many inducing strong and prevalent (i.e., immunodominant) T cell responses. Restricted by 40 and 14 HLA-class I and II allotypes, respectively, these responses have wide population coverage and might be of considerable academic, diagnostic and therapeutic interest. The broad coverage of epitopes and HLA overcame the otherwise confounding effects of HLA diversity and non-HLA background providing the first evidence of T cell immunodomination in humans. Also, double-staining of CD4+ T cells with tetramers representing the same HLA-binding core, albeit with different flanking regions, demonstrated an extensive diversification of the specificities of many CD4+ T cell responses. We suggest that this could reduce the risk of pathogen escape, and that multi-tetramer staining is required to reveal the true magnitude and diversity of CD4+ T cell responses. Our T cell epitope discovery approach uses a combination of (1) overlapping peptides representing the entire Yellow Fever virus proteome to search for peptides containing CD4+ and/or CD8+ T cell epitopes, (2) predictors of peptide-HLA binding to suggest epitopes and their restricting HLA allotypes, (3) generation of peptide-HLA tetramers to identify T cell epitopes, and (4) analysis of ex vivo T cell responses to validate the same. This approach is systematic, exhaustive, and can be done in any individual of any HLA haplotype. It is all-inclusive in the sense that it includes all protein antigens and peptide epitopes, and encompasses both CD4+ and CD8+ T cell epitopes. It is efficient and, importantly, reduces the false discovery rate. The unbiased nature of the T cell epitope discovery approach presented here should support the refinement of future peptide-HLA class I and II predictors and tetramer technologies, which eventually should cover all HLA class I and II isotypes. We believe that future investigations of emerging pathogens (e.g., SARS-CoV-2) should include population-wide T cell epitope discovery using blood samples from patients, convalescents and/or long-term survivors, who might all hold important information on T cell epitopes and responses.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Epitopes, T-Lymphocyte/immunology , Vaccination , Yellow Fever Vaccine/immunology , Yellow Fever/prevention & control , Yellow fever virus/immunology , Betacoronavirus/immunology , COVID-19 , Cohort Studies , Coronavirus Infections/prevention & control , Coronavirus Infections/virology , Healthy Volunteers , Histocompatibility Antigens Class I/immunology , Histocompatibility Antigens Class II/immunology , Humans , Immunogenicity, Vaccine , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Pneumonia, Viral/virology , SARS-CoV-2 , Yellow Fever/virology
17.
Sci Immunol ; 6(58)2021 04 14.
Article in English | MEDLINE | ID: covidwho-1186202

ABSTRACT

T cells are important for effective viral clearance, elimination of virus-infected cells and long-term disease protection. To examine the full-spectrum of CD8+ T cell immunity in COVID-19, we experimentally evaluated 3141 major histocompatibility (MHC) class I-binding peptides covering the complete SARS-CoV-2 genome. Using DNA-barcoded peptide-MHC complex (pMHC) multimers combined with a T cell phenotype panel, we report a comprehensive list of 122 immunogenic and a subset of immunodominant SARS-CoV-2 T cell epitopes. Substantial CD8+ T cell recognition was observed in COVID-19 patients, with up to 27% of all CD8+ lymphocytes interacting with SARS-CoV-2-derived epitopes. Most immunogenic regions were derived from open reading frame (ORF) 1 and ORF3, with ORF1 containing most of the immunodominant epitopes. CD8+ T cell recognition of lower affinity was also observed in healthy donors toward SARS-CoV-2-derived epitopes. This pre-existing T cell recognition signature was partially overlapping with the epitope landscape observed in COVID-19 patients and may drive the further expansion of T cell responses to SARS-CoV-2 infection. Importantly the phenotype of the SARS-CoV-2-specific CD8+ T cells, revealed a strong T cell activation in COVID-19 patients, while minimal T cell activation was seen in healthy individuals. We found that patients with severe disease displayed significantly larger SARS-CoV-2-specific T cell populations compared to patients with mild diseases and these T cells displayed a robust activation profile. These results further our understanding of T cell immunity to SARS-CoV-2 infection and hypothesize that strong antigen-specific T cell responses are associated with different disease outcomes.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , COVID-19/immunology , Epitopes, T-Lymphocyte/immunology , Immunodominant Epitopes/immunology , SARS-CoV-2 , Adult , Aged , Aged, 80 and over , DNA Barcoding, Taxonomic , Epitope Mapping , Female , Genome, Viral , Humans , Major Histocompatibility Complex/genetics , Male , Middle Aged , Peptides/immunology , SARS-CoV-2/genetics , SARS-CoV-2/immunology
18.
Nat Commun ; 12(1): 324, 2021 01 12.
Article in English | MEDLINE | ID: covidwho-1026822

ABSTRACT

The rapid development of a SARS-CoV-2 vaccine is a global priority. Here, we develop two capsid-like particle (CLP)-based vaccines displaying the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein. RBD antigens are displayed on AP205 CLPs through a split-protein Tag/Catcher, ensuring unidirectional and high-density display of RBD. Both soluble recombinant RBD and RBD displayed on CLPs bind the ACE2 receptor with nanomolar affinity. Mice are vaccinated with soluble RBD or CLP-displayed RBD, formulated in Squalene-Water-Emulsion. The RBD-CLP vaccines induce higher levels of serum anti-spike antibodies than the soluble RBD vaccines. Remarkably, one injection with our lead RBD-CLP vaccine in mice elicits virus neutralization antibody titers comparable to those found in patients that had recovered from COVID-19. Following booster vaccinations, the virus neutralization titers exceed those measured after natural infection, at serum dilutions above 1:10,000. Thus, the RBD-CLP vaccine is a highly promising candidate for preventing COVID-19.


Subject(s)
Antibodies, Neutralizing/immunology , COVID-19 Vaccines/immunology , Capsid/immunology , Protein Binding/immunology , SARS-CoV-2/immunology , Angiotensin-Converting Enzyme 2 , Animals , Antibodies, Viral/immunology , COVID-19/prevention & control , Female , Humans , Immunogenicity, Vaccine , Kinetics , Mice , Mice, Inbred BALB C , Protein Binding/genetics , Recombinant Proteins/genetics , Recombinant Proteins/immunology , Serologic Tests , Spike Glycoprotein, Coronavirus/immunology
19.
Cell ; 183(1): 158-168.e14, 2020 10 01.
Article in English | MEDLINE | ID: covidwho-714204

ABSTRACT

SARS-CoV-2-specific memory T cells will likely prove critical for long-term immune protection against COVID-19. Here, we systematically mapped the functional and phenotypic landscape of SARS-CoV-2-specific T cell responses in unexposed individuals, exposed family members, and individuals with acute or convalescent COVID-19. Acute-phase SARS-CoV-2-specific T cells displayed a highly activated cytotoxic phenotype that correlated with various clinical markers of disease severity, whereas convalescent-phase SARS-CoV-2-specific T cells were polyfunctional and displayed a stem-like memory phenotype. Importantly, SARS-CoV-2-specific T cells were detectable in antibody-seronegative exposed family members and convalescent individuals with a history of asymptomatic and mild COVID-19. Our collective dataset shows that SARS-CoV-2 elicits broadly directed and functionally replete memory T cell responses, suggesting that natural exposure or infection may prevent recurrent episodes of severe COVID-19.


Subject(s)
Convalescence , Coronavirus Infections/immunology , Pneumonia, Viral/immunology , T-Lymphocytes/immunology , Adult , Antibodies, Viral/immunology , Asymptomatic Infections , Betacoronavirus/immunology , COVID-19 , Coronavirus Infections/pathology , Female , Humans , Immunologic Memory , Male , Middle Aged , Pandemics , Pneumonia, Viral/pathology , SARS-CoV-2
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