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1.
Cell ; 185(6): 1025-1040.e14, 2022 03 17.
Article in English | MEDLINE | ID: covidwho-1649487

ABSTRACT

During the SARS-CoV-2 pandemic, novel and traditional vaccine strategies have been deployed globally. We investigated whether antibodies stimulated by mRNA vaccination (BNT162b2), including third-dose boosting, differ from those generated by infection or adenoviral (ChAdOx1-S and Gam-COVID-Vac) or inactivated viral (BBIBP-CorV) vaccines. We analyzed human lymph nodes after infection or mRNA vaccination for correlates of serological differences. Antibody breadth against viral variants is lower after infection compared with all vaccines evaluated but improves over several months. Viral variant infection elicits variant-specific antibodies, but prior mRNA vaccination imprints serological responses toward Wuhan-Hu-1 rather than variant antigens. In contrast to disrupted germinal centers (GCs) in lymph nodes during infection, mRNA vaccination stimulates robust GCs containing vaccine mRNA and spike antigen up to 8 weeks postvaccination in some cases. SARS-CoV-2 antibody specificity, breadth, and maturation are affected by imprinting from exposure history and distinct histological and antigenic contexts in infection compared with vaccination.


Subject(s)
COVID-19 , Antibodies, Viral , COVID-19/prevention & control , Germinal Center , Humans , RNA, Messenger , SARS-CoV-2 , Vaccination
2.
Sci Transl Med ; 14(635): eabm7853, 2022 03 09.
Article in English | MEDLINE | ID: covidwho-1630954

ABSTRACT

A damaging inflammatory response is implicated in the pathogenesis of severe coronavirus disease 2019 (COVID-19), but mechanisms contributing to this response are unclear. In two prospective cohorts, early non-neutralizing, afucosylated immunoglobulin G (IgG) antibodies specific to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were associated with progression from mild to more severe COVID-19. To study the biology of afucosylated IgG immune complexes, we developed an in vivo model that revealed that human IgG-Fc-gamma receptor (FcγR) interactions could regulate inflammation in the lung. Afucosylated IgG immune complexes isolated from patients with COVID-19 induced inflammatory cytokine production and robust infiltration of the lung by immune cells. In contrast to the antibody structures that were associated with disease progression, antibodies that were elicited by messenger RNA SARS-CoV-2 vaccines were highly fucosylated and enriched in sialylation, both modifications that reduce the inflammatory potential of IgG. Vaccine-elicited IgG did not promote an inflammatory lung response. These results show that human IgG-FcγR interactions regulate inflammation in the lung and define distinct lung activities mediated by the IgG that are associated with protection against, or progression to, severe COVID-19.


Subject(s)
COVID-19 , Antibodies, Neutralizing , Antibodies, Viral , Antibody Formation , COVID-19 Vaccines , Humans , Prospective Studies , SARS-CoV-2 , Spike Glycoprotein, Coronavirus
4.
Nature ; 596(7872): 410-416, 2021 08.
Article in English | MEDLINE | ID: covidwho-1305364

ABSTRACT

The emergency use authorization of two mRNA vaccines in less than a year from the emergence of SARS-CoV-2 represents a landmark in vaccinology1,2. Yet, how mRNA vaccines stimulate the immune system to elicit protective immune responses is unknown. Here we used a systems vaccinology approach to comprehensively profile the innate and adaptive immune responses of 56 healthy volunteers who were vaccinated with the Pfizer-BioNTech mRNA vaccine (BNT162b2). Vaccination resulted in the robust production of neutralizing antibodies against the wild-type SARS-CoV-2 (derived from 2019-nCOV/USA_WA1/2020) and, to a lesser extent, the B.1.351 strain, as well as significant increases in antigen-specific polyfunctional CD4 and CD8 T cells after the second dose. Booster vaccination stimulated a notably enhanced innate immune response as compared to primary vaccination, evidenced by (1) a greater frequency of CD14+CD16+ inflammatory monocytes; (2) a higher concentration of plasma IFNγ; and (3) a transcriptional signature of innate antiviral immunity. Consistent with these observations, our single-cell transcriptomics analysis demonstrated an approximately 100-fold increase in the frequency of a myeloid cell cluster enriched in interferon-response transcription factors and reduced in AP-1 transcription factors, after secondary immunization. Finally, we identified distinct innate pathways associated with CD8 T cell and neutralizing antibody responses, and show that a monocyte-related signature correlates with the neutralizing antibody response against the B.1.351 variant. Collectively, these data provide insights into the immune responses induced by mRNA vaccination and demonstrate its capacity to prime the innate immune system to mount a more potent response after booster immunization.


Subject(s)
Adaptive Immunity , Antibodies, Viral/immunology , COVID-19 Vaccines/immunology , COVID-19/immunology , Immunity, Innate , T-Lymphocytes/immunology , Vaccinology , Adult , Aged , Antibodies, Neutralizing/immunology , Autoantibodies/immunology , COVID-19 Vaccines/administration & dosage , Female , Humans , Immunization, Secondary , Male , Middle Aged , Single-Cell Analysis , Spike Glycoprotein, Coronavirus/immunology , Transcription, Genetic , Transcriptome/genetics , Young Adult
5.
Sci Immunol ; 6(61)2021 07 01.
Article in English | MEDLINE | ID: covidwho-1295163

ABSTRACT

A central feature of the SARS-CoV-2 pandemic is that some individuals become severely ill or die, whereas others have only a mild disease course or are asymptomatic. Here we report development of an improved multimeric αß T cell staining reagent platform, with each maxi-ferritin "spheromer" displaying 12 peptide-MHC complexes. Spheromers stain specific T cells more efficiently than peptide-MHC tetramers and capture a broader portion of the sequence repertoire for a given peptide-MHC. Analyzing the response in unexposed individuals, we find that T cells recognizing peptides conserved amongst coronaviruses are more abundant and tend to have a "memory" phenotype, compared to those unique to SARS-CoV-2. Significantly, CD8+ T cells with these conserved specificities are much more abundant in COVID-19 patients with mild disease versus those with a more severe illness, suggesting a protective role.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , COVID-19/immunology , Epitopes, T-Lymphocyte/immunology , SARS-CoV-2/immunology , Severity of Illness Index , CD8-Positive T-Lymphocytes/pathology , COVID-19/pathology , Female , Humans , Male
6.
iScience ; 24(4): 102311, 2021 Apr 23.
Article in English | MEDLINE | ID: covidwho-1129054

ABSTRACT

We describe a physics-based learning model for predicting the immunogenicity of cytotoxic T lymphocyte (CTL) epitopes derived from diverse pathogens including SARS-CoV-2. The model was trained and optimized on the relative immunodominance of CTL epitopes in human immunodeficiency virus infection. Its accuracy was tested against experimental data from patients with COVID-19. Our model predicts that only some SARS-CoV-2 epitopes predicted to bind to HLA molecules are immunogenic. The immunogenic CTL epitopes across all SARS-CoV-2 proteins are predicted to provide broad population coverage, but those from the SARS-CoV-2 spike protein alone are unlikely to do so. Our model also predicts that several immunogenic SARS-CoV-2 CTL epitopes are identical to seasonal coronaviruses circulating in the population and such cross-reactive CD8+ T cells can indeed be detected in prepandemic blood donors, suggesting that some level of CTL immunity against COVID-19 may be present in some individuals before SARS-CoV-2 infection.

7.
Nat Immunol ; 22(1): 67-73, 2021 01.
Article in English | MEDLINE | ID: covidwho-1065904

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 infections can cause coronavirus disease 2019 (COVID-19), which manifests with a range of severities from mild illness to life-threatening pneumonia and multi-organ failure. Severe COVID-19 is characterized by an inflammatory signature, including high levels of inflammatory cytokines, alveolar inflammatory infiltrates and vascular microthrombi. Here we show that patients with severe COVID-19 produced a unique serologic signature, including an increased likelihood of IgG1 with afucosylated Fc glycans. This Fc modification on severe acute respiratory syndrome coronavirus 2 IgGs enhanced interactions with the activating Fcγ receptor FcγRIIIa; when incorporated into immune complexes, Fc afucosylation enhanced production of inflammatory cytokines by monocytes, including interleukin-6 and tumor necrosis factor. These results show that disease severity in COVID-19 correlates with the presence of proinflammatory IgG Fc structures, including afucosylated IgG1.


Subject(s)
COVID-19/immunology , Cytokines/immunology , Immunoglobulin G/immunology , Receptors, IgG/immunology , SARS-CoV-2/immunology , Adolescent , Adult , Aged , COVID-19/metabolism , COVID-19/virology , Child , Cytokines/metabolism , Female , Glycosylation , Humans , Immunoglobulin G/metabolism , Interleukin-6 , Male , Middle Aged , Receptors, IgG/metabolism , SARS-CoV-2/metabolism , SARS-CoV-2/physiology , Severity of Illness Index , Tumor Necrosis Factor-alpha/immunology , Tumor Necrosis Factor-alpha/metabolism
8.
Adv Drug Deliv Rev ; 172: 314-338, 2021 05.
Article in English | MEDLINE | ID: covidwho-1039241

ABSTRACT

The ongoing SARS-CoV-2 pandemic has led to the focused application of resources and scientific expertise toward the goal of developing investigational vaccines to prevent COVID-19. The highly collaborative global efforts by private industry, governments and non-governmental organizations have resulted in a number of SARS-CoV-2 vaccine candidates moving to Phase III trials in a period of only months since the start of the pandemic. In this review, we provide an overview of the preclinical and clinical data on SARS-CoV-2 vaccines that are currently in Phase III clinical trials and in few cases authorized for emergency use. We further discuss relevant vaccine platforms and provide a discussion of SARS-CoV-2 antigens that may be targeted to increase the breadth and durability of vaccine responses.


Subject(s)
COVID-19 Vaccines/administration & dosage , COVID-19/prevention & control , Clinical Trials, Phase III as Topic/methods , SARS-CoV-2/drug effects , Animals , COVID-19/epidemiology , COVID-19/immunology , COVID-19 Vaccines/chemistry , COVID-19 Vaccines/immunology , Drug Evaluation, Preclinical/methods , Drug Evaluation, Preclinical/trends , Humans , Protein Structure, Secondary , Protein Structure, Tertiary , SARS-CoV-2/chemistry , SARS-CoV-2/immunology
9.
Nat Med ; 27(1): 125-135, 2021 01.
Article in English | MEDLINE | ID: covidwho-1023963

ABSTRACT

Most of what we know about adaptive immunity has come from inbred mouse studies, using methods that are often difficult or impossible to confirm in humans. In addition, vaccine responses in mice are often poorly predictive of responses to those same vaccines in humans. Here we use human tonsils, readily available lymphoid organs, to develop a functional organotypic system that recapitulates key germinal center features in vitro, including the production of antigen-specific antibodies, somatic hypermutation and affinity maturation, plasmablast differentiation and class-switch recombination. We use this system to define the essential cellular components necessary to produce an influenza vaccine response. We also show that it can be used to evaluate humoral immune responses to two priming antigens, rabies vaccine and an adenovirus-based severe acute respiratory syndrome coronavirus 2 vaccine, and to assess the effects of different adjuvants. This system should prove useful for studying critical mechanisms underlying adaptive immunity in much greater depth than previously possible and to rapidly test vaccine candidates and adjuvants in an entirely human system.


Subject(s)
Influenza Vaccines/immunology , Palatine Tonsil/immunology , Adjuvants, Immunologic , B-Lymphocytes/cytology , B-Lymphocytes/immunology , COVID-19 Vaccines/immunology , Germinal Center/cytology , Hemagglutinin Glycoproteins, Influenza Virus , Humans , In Vitro Techniques , Lymphoid Tissue/immunology , Measles-Mumps-Rubella Vaccine/immunology , Organoids/cytology , Organoids/immunology , Rabies Vaccines/immunology , T-Lymphocytes/immunology
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