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1.
Cell Rep ; 38(9): 110429, 2022 03 01.
Article in English | MEDLINE | ID: covidwho-1734242

ABSTRACT

Continuous emergence of SARS-CoV-2 variants of concern (VOCs) is fueling the COVID-19 pandemic. Omicron (B.1.1.529) rapidly spread worldwide. The large number of mutations in its Spike raise concerns about a major antigenic drift that could significantly decrease vaccine efficacy and infection-induced immunity. A long interval between BNT162b2 mRNA doses elicits antibodies that efficiently recognize Spikes from different VOCs. Here, we evaluate the recognition of Omicron Spike by plasma from a cohort of SARS-CoV-2 naive and previously infected individuals who received their BNT162b2 mRNA vaccine 16 weeks apart. Omicron Spike is recognized less efficiently than D614G, Alpha, Beta, Gamma, and Delta Spikes. We compare with plasma activity from participants receiving a short (4 weeks) interval regimen. Plasma from individuals of the long-interval cohort recognize and neutralize better the Omicron Spike compared with those who received a short interval. Whether this difference confers any clinical benefit against Omicron remains unknown.


Subject(s)
Antibodies, Neutralizing/blood , Immunization Schedule , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Adult , Aged , Antibodies, Neutralizing/analysis , Antibodies, Neutralizing/immunology , Antibodies, Viral/analysis , Antibodies, Viral/blood , Antibodies, Viral/immunology , Cohort Studies , Female , HEK293 Cells , Humans , Immunization, Secondary/methods , Male , Middle Aged , Quebec , SARS-CoV-2/pathogenicity , Time Factors , Vaccination/methods , Vaccine Potency , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/immunology , Young Adult , /immunology
2.
Viruses ; 14(3)2022 03 04.
Article in English | MEDLINE | ID: covidwho-1732239

ABSTRACT

SARS-CoV-2 infection rapidly elicits anti-Spike antibodies whose quantity in plasma gradually declines upon resolution of symptoms. This decline is part of the evolution of an immune response leading to B cell differentiation into short-lived antibody-secreting cells or resting memory B cells. At the same time, the ongoing class switch and antibody maturation processes occurring in germinal centers lead to the selection of B cell clones secreting antibodies with higher affinity for their cognate antigen, thereby improving their functional activity. To determine whether the decline in SARS-CoV-2 antibodies is paralleled with an increase in avidity of the anti-viral antibodies produced, we developed a simple assay to measure the avidity of anti-receptor binding domain (RBD) IgG elicited by SARS-CoV-2 infection. We longitudinally followed a cohort of 29 convalescent donors with blood samples collected between 6- and 32-weeks post-symptoms onset. We observed that, while the level of antibodies declines over time, the anti-RBD avidity progressively increases and correlates with the B cell class switch. Additionally, we observed that anti-RBD avidity increased similarly after SARS-CoV-2 mRNA vaccination and after SARS-CoV-2 infection. Our results suggest that anti-RBD IgG avidity determination could be a surrogate assay for antibody affinity maturation and, thus, suitable for studying humoral responses elicited by natural infection and/or vaccination.


Subject(s)
COVID-19 , Antibodies, Viral , Humans , Immunoglobulin G , Protein Binding , SARS-CoV-2/genetics
3.
Cell Host Microbe ; 30(1): 97-109.e5, 2022 01 12.
Article in English | MEDLINE | ID: covidwho-1549683

ABSTRACT

The standard regimen of the BNT162b2 mRNA vaccine for SARS-CoV-2 includes two doses administered three weeks apart. However, some public health authorities spaced these doses, raising questions about efficacy. We analyzed longitudinal humoral responses against the D614G strain and variants of concern for SARS-CoV-2 in a cohort of SARS-CoV-2-naive and previously infected individuals who received the BNT162b2 mRNA vaccine with sixteen weeks between doses. While administering a second dose to previously infected individuals did not significantly improve humoral responses, these responses significantly increased in naive individuals after a 16-week spaced second dose, achieving similar levels as in previously infected individuals. Comparing these responses to those elicited in individuals receiving a short (4-week) dose interval showed that a 16-week interval induced more robust responses among naive vaccinees. These findings suggest that a longer interval between vaccine doses does not compromise efficacy and may allow greater flexibility in vaccine administration.


Subject(s)
/immunology , COVID-19 Vaccines/immunology , COVID-19/immunology , Immunity, Humoral/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Vaccines, Synthetic/immunology , /immunology , Adult , Aged , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/virology , Female , Humans , Male , Middle Aged , Vaccination/methods , Young Adult
4.
Sci Adv ; 7(48): eabj5629, 2021 Nov 26.
Article in English | MEDLINE | ID: covidwho-1537882

ABSTRACT

Despite advances in COVID-19 management, identifying patients evolving toward death remains challenging. To identify early predictors of mortality within 60 days of symptom onset (DSO), we performed immunovirological assessments on plasma from 279 individuals. On samples collected at DSO11 in a discovery cohort, high severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral RNA (vRNA), low receptor binding domain­specific immunoglobulin G and antibody-dependent cellular cytotoxicity, and elevated cytokines and tissue injury markers were strongly associated with mortality, including in patients on mechanical ventilation. A three-variable model of vRNA, with predefined adjustment by age and sex, robustly identified patients with fatal outcome (adjusted hazard ratio for log-transformed vRNA = 3.5). This model remained robust in independent validation and confirmation cohorts. Since plasma vRNA's predictive accuracy was maintained at earlier time points, its quantitation can help us understand disease heterogeneity and identify patients who may benefit from new therapies.

5.
Immunity ; 54(9): 2143-2158.e15, 2021 09 14.
Article in English | MEDLINE | ID: covidwho-1364125

ABSTRACT

Neutralizing antibodies (NAbs) are effective in treating COVID-19, but the mechanism of immune protection is not fully understood. Here, we applied live bioluminescence imaging (BLI) to monitor the real-time effects of NAb treatment during prophylaxis and therapy of K18-hACE2 mice intranasally infected with SARS-CoV-2-nanoluciferase. Real-time imaging revealed that the virus spread sequentially from the nasal cavity to the lungs in mice and thereafter systemically to various organs including the brain, culminating in death. Highly potent NAbs from a COVID-19 convalescent subject prevented, and also effectively resolved, established infection when administered within three days. In addition to direct neutralization, depletion studies indicated that Fc effector interactions of NAbs with monocytes, neutrophils, and natural killer cells were required to effectively dampen inflammatory responses and limit immunopathology. Our study highlights that both Fab and Fc effector functions of NAbs are essential for optimal in vivo efficacy against SARS-CoV-2.


Subject(s)
Antibodies, Neutralizing/metabolism , Antibodies, Viral/metabolism , Brain/pathology , COVID-19/immunology , Lung/pathology , SARS-CoV-2/physiology , Testis/pathology , Angiotensin-Converting Enzyme 2/genetics , Animals , Antibodies, Neutralizing/genetics , Antibodies, Viral/genetics , Brain/virology , COVID-19/therapy , Cells, Cultured , Disease Models, Animal , Humans , Immunoglobulin Fc Fragments/genetics , Luciferases/genetics , Luminescent Measurements , Lung/virology , Male , Mice , Mice, Transgenic , Testis/virology
6.
Diagn Microbiol Infect Dis ; 101(4): 115521, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1363964

ABSTRACT

SARS-CoV-2 whole genome sequencing is a molecular biology tool performed to support many aspects of the response to the pandemic. Freezing of primary clinical nasopharyngeal swabs and shipment to reference laboratories is usually required for sequencing. Cobas PCR Media transport medium facilitates high throughput SARS-CoV-2 RT-PCR analyses on cobas platforms. The manufacturer doesn't recommend freezing this transport medium because of risks of degrading molecular templates and impairing test results. Our objective was to compare the quality and results of SARS-CoV-2 genomic sequencing when performed on fresh or frozen samples in cobas PCR Media. Viral genome sequencing was performed using Oxford Nanopore Technologies MinION platform. Sequencing performance, quality and results did not significantly differ between fresh and frozen samples (n = 10). Freezing of cobas PCR Media does not negatively affect SARS-CoV-2 RNA sequencing results and it is therefore a suitable transport medium for outsourcing sequencing analyses to reference laboratories.


Subject(s)
COVID-19 Testing/methods , COVID-19/diagnosis , Freezing , Polymerase Chain Reaction/methods , SARS-CoV-2/isolation & purification , Whole Genome Sequencing/methods , COVID-19/virology , Cryopreservation , Genome, Viral , Humans , Molecular Diagnostic Techniques/methods , Nasopharynx/virology , RNA, Viral/genetics , SARS-CoV-2/genetics
7.
PLoS One ; 16(5): e0245031, 2021.
Article in English | MEDLINE | ID: covidwho-1314324

ABSTRACT

SARS-CoV-2 infection causing the novel coronavirus disease 2019 (COVID-19) has been responsible for more than 2.8 million deaths and nearly 125 million infections worldwide as of March 2021. In March 2020, the World Health Organization determined that the COVID-19 outbreak is a global pandemic. The urgency and magnitude of this pandemic demanded immediate action and coordination between local, regional, national, and international actors. In that mission, researchers require access to high-quality biological materials and data from SARS-CoV-2 infected and uninfected patients, covering the spectrum of disease manifestations. The "Biobanque québécoise de la COVID-19" (BQC19) is a pan-provincial initiative undertaken in Québec, Canada to enable the collection, storage and sharing of samples and data related to the COVID-19 crisis. As a disease-oriented biobank based on high-quality biosamples and clinical data of hospitalized and non-hospitalized SARS-CoV-2 PCR positive and negative individuals. The BQC19 follows a legal and ethical management framework approved by local health authorities. The biosamples include plasma, serum, peripheral blood mononuclear cells and DNA and RNA isolated from whole blood. In addition to the clinical variables, BQC19 will provide in-depth analytical data derived from the biosamples including whole genome and transcriptome sequencing, proteome and metabolome analyses, multiplex measurements of key circulating markers as well as anti-SARS-CoV-2 antibody responses. BQC19 will provide the scientific and medical communities access to data and samples to better understand, manage and ultimately limit, the impact of COVID-19. In this paper we present BQC19, describe the process according to which it is governed and organized, and address opportunities for future research collaborations. BQC19 aims to be a part of a global communal effort addressing the challenges of COVID-19.


Subject(s)
Biological Specimen Banks/organization & administration , COVID-19/pathology , COVID-19/epidemiology , COVID-19/genetics , COVID-19/metabolism , Humans , Information Dissemination/methods , Pandemics , Quebec/epidemiology , SARS-CoV-2/isolation & purification
8.
Cell Rep Med ; 2(6): 100290, 2021 06 15.
Article in English | MEDLINE | ID: covidwho-1307252

ABSTRACT

With the recent approval of highly effective coronavirus disease 2019 (COVID-19) vaccines, functional and lasting immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently under investigation as antibody levels in plasma were shown to decline during convalescence. Since the absence of antibodies does not equate to absence of immune memory, we evaluate the presence of SARS-CoV-2-specific memory B cells in convalescent individuals. Here, we report a longitudinal assessment of humoral immune responses on 32 donors up to 8 months post-symptom onset. Our observations indicate that anti-Spike and anti-receptor binding domain (RBD) immunoglobulin M (IgM) in plasma decay rapidly, whereas the reduction of IgG is less prominent. Neutralizing activity also declines rapidly when compared to Fc-effector functions. Concomitantly, the frequencies of RBD-specific IgM+ B cells wane significantly when compared to RBD-specific IgG+ B cells, which remain stable. Our results add to the current understanding of immune memory following SARS-CoV-2 infection, which is critical for secondary infection prevention and vaccine efficacy.

9.
Cell Host Microbe ; 29(7): 1137-1150.e6, 2021 07 14.
Article in English | MEDLINE | ID: covidwho-1252574

ABSTRACT

While the standard regimen of the BNT162b2 mRNA vaccine for SARS-CoV-2 includes two doses administered 3 weeks apart, some public health authorities are spacing these doses, raising concerns about efficacy. However, data indicate that a single dose can be up to 90% effective starting 14 days post-administration. To assess the mechanisms contributing to protection, we analyzed humoral and T cell responses three weeks after a single BNT162b2 dose. We observed weak neutralizing activity elicited in SARS-CoV-2 naive individuals but strong anti-receptor binding domain and spike antibodies with Fc-mediated effector functions and cellular CD4+ T cell responses. In previously infected individuals, a single dose boosted all humoral and T cell responses, with strong correlations between T helper and antibody immunity. Our results highlight the potential role of Fc-mediated effector functions and T cell responses in vaccine efficacy. They also provide support for spacing doses to vaccinate more individuals in conditions of vaccine scarcity.


Subject(s)
Antibodies, Viral/immunology , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/immunology , COVID-19/immunology , SARS-CoV-2/immunology , T-Lymphocytes/immunology , Adult , Antibodies, Neutralizing/immunology , Antibodies, Viral/chemistry , Betacoronavirus , COVID-19/prevention & control , Carrier Proteins , Female , Humans , Immunity , Immunoglobulin Fc Fragments , Male , Middle Aged , Vaccination , Vaccines, Synthetic/immunology , Young Adult
10.
PLoS One ; 16(5): e0245031, 2021.
Article in English | MEDLINE | ID: covidwho-1234580

ABSTRACT

SARS-CoV-2 infection causing the novel coronavirus disease 2019 (COVID-19) has been responsible for more than 2.8 million deaths and nearly 125 million infections worldwide as of March 2021. In March 2020, the World Health Organization determined that the COVID-19 outbreak is a global pandemic. The urgency and magnitude of this pandemic demanded immediate action and coordination between local, regional, national, and international actors. In that mission, researchers require access to high-quality biological materials and data from SARS-CoV-2 infected and uninfected patients, covering the spectrum of disease manifestations. The "Biobanque québécoise de la COVID-19" (BQC19) is a pan-provincial initiative undertaken in Québec, Canada to enable the collection, storage and sharing of samples and data related to the COVID-19 crisis. As a disease-oriented biobank based on high-quality biosamples and clinical data of hospitalized and non-hospitalized SARS-CoV-2 PCR positive and negative individuals. The BQC19 follows a legal and ethical management framework approved by local health authorities. The biosamples include plasma, serum, peripheral blood mononuclear cells and DNA and RNA isolated from whole blood. In addition to the clinical variables, BQC19 will provide in-depth analytical data derived from the biosamples including whole genome and transcriptome sequencing, proteome and metabolome analyses, multiplex measurements of key circulating markers as well as anti-SARS-CoV-2 antibody responses. BQC19 will provide the scientific and medical communities access to data and samples to better understand, manage and ultimately limit, the impact of COVID-19. In this paper we present BQC19, describe the process according to which it is governed and organized, and address opportunities for future research collaborations. BQC19 aims to be a part of a global communal effort addressing the challenges of COVID-19.


Subject(s)
Biological Specimen Banks/organization & administration , COVID-19/pathology , COVID-19/epidemiology , COVID-19/genetics , COVID-19/metabolism , Humans , Information Dissemination/methods , Pandemics , Quebec/epidemiology , SARS-CoV-2/isolation & purification
11.
J Clin Invest ; 131(8)2021 04 15.
Article in English | MEDLINE | ID: covidwho-1186423

ABSTRACT

Dysregulated immune profiles have been described in symptomatic patients infected with SARS-CoV-2. Whether the reported immune alterations are specific to SARS-CoV-2 infection or also triggered by other acute illnesses remains unclear. We performed flow cytometry analysis on fresh peripheral blood from a consecutive cohort of (a) patients hospitalized with acute SARS-CoV-2 infection, (b) patients of comparable age and sex hospitalized for another acute disease (SARS-CoV-2 negative), and (c) healthy controls. Using both data-driven and hypothesis-driven analyses, we found several dysregulations in immune cell subsets (e.g., decreased proportion of T cells) that were similarly associated with acute SARS-CoV-2 infection and non-COVID-19-related acute illnesses. In contrast, we identified specific differences in myeloid and lymphocyte subsets that were associated with SARS-CoV-2 status (e.g., elevated proportion of ICAM-1+ mature/activated neutrophils, ALCAM+ monocytes, and CD38+CD8+ T cells). A subset of SARS-CoV-2-specific immune alterations correlated with disease severity, disease outcome at 30 days, and mortality. Our data provide an understanding of the immune dysregulation specifically associated with SARS-CoV-2 infection among acute care hospitalized patients. Our study lays the foundation for the development of specific biomarkers to stratify SARS-CoV-2-positive patients at risk of unfavorable outcomes and to uncover candidate molecules to investigate from a therapeutic perspective.


Subject(s)
COVID-19/immunology , Leukocytes/classification , Leukocytes/immunology , SARS-CoV-2 , Acute Disease , Adult , Aged , B-Lymphocyte Subsets/immunology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , COVID-19/epidemiology , COVID-19/mortality , Case-Control Studies , Cohort Studies , Female , Hospitalization , Humans , Lymphocyte Activation , Male , Middle Aged , Models, Immunological , Monocytes/immunology , Multivariate Analysis , Neutrophils/immunology , Pandemics , Prognosis , Prospective Studies , Quebec/epidemiology , Risk Factors , SARS-CoV-2/immunology , Severity of Illness Index
12.
Nat Med ; 27(4): 659-667, 2021 04.
Article in English | MEDLINE | ID: covidwho-1104522

ABSTRACT

To identify circulating proteins influencing Coronavirus Disease 2019 (COVID-19) susceptibility and severity, we undertook a two-sample Mendelian randomization (MR) study, rapidly scanning hundreds of circulating proteins while reducing bias due to reverse causation and confounding. In up to 14,134 cases and 1.2 million controls, we found that an s.d. increase in OAS1 levels was associated with reduced COVID-19 death or ventilation (odds ratio (OR) = 0.54, P = 7 × 10-8), hospitalization (OR = 0.61, P = 8 × 10-8) and susceptibility (OR = 0.78, P = 8 × 10-6). Measuring OAS1 levels in 504 individuals, we found that higher plasma OAS1 levels in a non-infectious state were associated with reduced COVID-19 susceptibility and severity. Further analyses suggested that a Neanderthal isoform of OAS1 in individuals of European ancestry affords this protection. Thus, evidence from MR and a case-control study support a protective role for OAS1 in COVID-19 adverse outcomes. Available pharmacological agents that increase OAS1 levels could be prioritized for drug development.


Subject(s)
2',5'-Oligoadenylate Synthetase/physiology , COVID-19/etiology , Genetic Predisposition to Disease , SARS-CoV-2 , 2',5'-Oligoadenylate Synthetase/genetics , Aged , Aged, 80 and over , Animals , COVID-19/genetics , Case-Control Studies , Female , Humans , Interleukin-10 Receptor beta Subunit/genetics , Male , Mendelian Randomization Analysis , Middle Aged , Neanderthals , Protein Isoforms/physiology , Quantitative Trait Loci , Severity of Illness Index
13.
mBio ; 11(5)2020 10 16.
Article in English | MEDLINE | ID: covidwho-873469

ABSTRACT

In the absence of effective vaccines and with limited therapeutic options, convalescent plasma is being collected across the globe for potential transfusion to coronavirus disease 2019 (COVID-19) patients. The therapy has been deemed safe, and several clinical trials assessing its efficacy are ongoing. While it remains to be formally proven, the presence of neutralizing antibodies is thought to play a positive role in the efficacy of this treatment. Indeed, neutralizing titers of ≥1:160 have been recommended in some convalescent plasma trials for inclusion. Here, we performed repeated analyses at 1-month intervals on 31 convalescent individuals to evaluate how the humoral responses against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Spike glycoprotein, including neutralization, evolve over time. We observed that the levels of receptor-binding-domain (RBD)-specific IgG and IgA slightly decreased between 6 and 10 weeks after the onset of symptoms but that RBD-specific IgM levels decreased much more abruptly. Similarly, we observed a significant decrease in the capacity of convalescent plasma to neutralize pseudoparticles bearing wild-type SARS-CoV-2 S or its D614G variant. If neutralization activity proves to be an important factor in the clinical efficacy of convalescent plasma transfer, our results suggest that plasma from convalescent donors should be recovered rapidly after resolution of symptoms.IMPORTANCE While waiting for an efficient vaccine to protect against SARS-CoV-2 infection, alternative approaches to treat or prevent acute COVID-19 are urgently needed. Transfusion of convalescent plasma to treat COVID-19 patients is currently being explored; neutralizing activity in convalescent plasma is thought to play a central role in the efficacy of this treatment. Here, we observed that plasma neutralization activity decreased a few weeks after the onset of the symptoms. If neutralizing activity is required for the efficacy of convalescent plasma transfer, our results suggest that convalescent plasma should be recovered rapidly after the donor recovers from active infection.


Subject(s)
Betacoronavirus/immunology , Convalescence , Coronavirus Infections/immunology , Immunity, Humoral , Pneumonia, Viral/immunology , Spike Glycoprotein, Coronavirus/immunology , Adult , Aged , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19 , Coronavirus Infections/blood , Cross Reactions , Female , Humans , Male , Middle Aged , Pandemics , Pneumonia, Viral/blood , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/chemistry , Young Adult
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