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1.
Cell Rep ; 38(12): 110561, 2022 03 22.
Article in English | MEDLINE | ID: covidwho-1797095

ABSTRACT

Eliciting antibodies to surface-exposed viral glycoproteins can generate protective responses that control and prevent future infections. Targeting conserved sites may reduce the likelihood of viral escape and limit the spread of related viruses with pandemic potential. Here we leverage rational immunogen design to focus humoral responses on conserved epitopes. Using glycan engineering and epitope scaffolding in boosting immunogens, we focus murine serum antibody responses to conserved receptor binding motif (RBM) and receptor binding domain (RBD) epitopes following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike imprinting. Although all engineered immunogens elicit a robust SARS-CoV-2-neutralizing serum response, RBM-focusing immunogens exhibit increased potency against related sarbecoviruses, SARS-CoV, WIV1-CoV, RaTG13-CoV, and SHC014-CoV; structural characterization of representative antibodies defines a conserved epitope. RBM-focused sera confer protection against SARS-CoV-2 challenge. Thus, RBM focusing is a promising strategy to elicit breadth across emerging sarbecoviruses without compromising SARS-CoV-2 protection. These engineering strategies are adaptable to other viral glycoproteins for targeting conserved epitopes.


Subject(s)
COVID-19 , Viral Envelope Proteins , Animals , Mice , Mice, Inbred BALB C , SARS-CoV-2 , Spike Glycoprotein, Coronavirus
2.
Cell reports ; 2022.
Article in English | EuropePMC | ID: covidwho-1728215

ABSTRACT

Hauser et al. use structure-guided design to engineer SARS-2 immunogens that direct immune responses to conserved viral sites in context of preexisting immunity. In mice, these immunogens elicit antibodies that potently neutralize related coronaviruses, including those of potential pandemic concern. Structural characterization of selected antibodies explains this observation.

3.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-312141

ABSTRACT

Effective countermeasures are needed against emerging coronaviruses of pandemic potential, similar to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Designing immunogens that elicit broadly neutralizing antibodies to conserved viral epitopes on the major surface glycoprotein, spike, such as the receptor binding domain (RBD) is one potential approach. Here, we report the generation of homotrimeric RBD immunogens from different sarbecoviruses using a stabilized, immune-silent trimerization tag. We find that a cocktail of these homotrimeric sarbecovirus RBDs elicit antibodies to conserved viral epitopes outside of the ACE-2 receptor binding motif. Importantly, these responses neutralize all sarbecovirus components even in context of prior SARS-CoV-2 imprinting. This may be an effective strategy for eliciting broadly neutralizing responses leading to a pan-sarbecovirus vaccine.Funding: We acknowledge funding from NIH R01s AI146779 (AGS), AI124378,AI137057 and AI153098 (DL), and a Massachusetts Consortium on Pathogenesis Readiness (MassCPR) grant (AGS);training grants: NIGMS T32 GM007753 (BMH and TMC);T32AI007245 (JF);F31 Al138368 (MS). A.B.B. is supported by the National Institutes for Drug Abuse (NIDA) Avenir New Innovator Award DP2DA040254, the MGH Transformative Scholars Program as well as funding from the Charles H. Hood Foundation. This independent research was supported by the Gilead Sciences Research Scholars Program in HIV.Conflict of Interest: Authors declare no competing interests.Ethical Approval: All experiments were conducted with institutional IACUC approval (MGH protocol 2014N000252).

5.
Cell ; 185(3): 457-466.e4, 2022 02 03.
Article in English | MEDLINE | ID: covidwho-1611649

ABSTRACT

Recent surveillance has revealed the emergence of the SARS-CoV-2 Omicron variant (BA.1/B.1.1.529) harboring up to 36 mutations in spike protein, the target of neutralizing antibodies. Given its potential to escape vaccine-induced humoral immunity, we measured the neutralization potency of sera from 88 mRNA-1273, 111 BNT162b, and 40 Ad26.COV2.S vaccine recipients against wild-type, Delta, and Omicron SARS-CoV-2 pseudoviruses. We included individuals that received their primary series recently (<3 months), distantly (6-12 months), or an additional "booster" dose, while accounting for prior SARS-CoV-2 infection. Remarkably, neutralization of Omicron was undetectable in most vaccinees. However, individuals boosted with mRNA vaccines exhibited potent neutralization of Omicron, only 4-6-fold lower than wild type, suggesting enhanced cross-reactivity of neutralizing antibody responses. In addition, we find that Omicron pseudovirus infects more efficiently than other variants tested. Overall, this study highlights the importance of additional mRNA doses to broaden neutralizing antibody responses against highly divergent SARS-CoV-2 variants.

6.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-296679

ABSTRACT

Recent surveillance has revealed the emergence of the SARS-CoV-2 Omicron variant (BA.1/B.1.1.529) harboring up to 36 mutations in spike protein, the target of vaccine-induced neutralizing antibodies. Given its potential to escape vaccine-induced humoral immunity, we measured neutralization potency of sera from 88 mRNA-1273, 111 BNT162b, and 40 Ad26.COV2.S vaccine recipients against wild type, Delta, and Omicron SARS-CoV-2 pseudoviruses. We included individuals that were vaccinated recently (<3 months), distantly (6-12 months), or recently boosted, and accounted for prior SARS-CoV-2 infection. Remarkably, neutralization of Omicron was undetectable in most vaccinated individuals. However, individuals boosted with mRNA vaccines exhibited potent neutralization of Omicron only 4-6-fold lower than wild type, suggesting that boosters enhance the cross-reactivity of neutralizing antibody responses. In addition, we find Omicron pseudovirus is significantly more infectious than any other variant tested. Overall, this study highlights the importance of boosters to broaden neutralizing antibody responses against highly divergent SARS-CoV-2 variants.

7.
PubMed; 2020.
Preprint in English | PubMed | ID: ppcovidwho-292772

ABSTRACT

Humoral responses in COVID-19 disease are often of limited durability, as seen with other human coronavirus epidemics. To address the underlying etiology, we examined postmortem thoracic lymph nodes and spleens in acute SARS-CoV-2 infection and observed the absence of germinal centers, a striking reduction in Bcl-6+ germinal center B cells but preservation of AID+ B cells. Absence of germinal centers correlated with an early specific block in Bcl-6+TFH cell differentiation together with an increase in T-bet+TH1 cells and aberrant extra-follicular TNF-a accumulation. Parallel peripheral blood studies revealed loss of transitional and follicular B cells in severe disease and accumulation of SARS-CoV-2-specific "disease-related" B cell populations. These data identify defective Bcl-6+TFH cell generation and dysregulated humoral immune induction early in COVID-19 disease, providing a mechanistic explanation for the limited durability of antibody responses in coronavirus infections and suggest that achieving herd immunity through natural infection may be difficult. Funding: This work was supported by NIH U19 AI110495 to SP, NIH R01 AI146779 to AGS, NIH R01AI137057 and DP2DA042422 to DL, BMH was supported by NIGMS T32 GM007753, TMC was supported by T32 AI007245. Funding for these studies from the Massachusetts Consortium of Pathogen Readiness, the Mark and Lisa Schwartz Foundation and Enid Schwartz is also acknowledged. Conflict of Interest: None. Ethical Approval: This study was performed with the approval of the Institutional Review Boards at the Massachusetts General Hospital and the Brigham and Women's Hospital.

8.
SSRN; 2021.
Preprint in English | SSRN | ID: ppcovidwho-291966

ABSTRACT

Eliciting antibodies to surface-exposed viral glycoproteins can generate protective responses that control and prevent future infections. Targeting conserved sites may reduce the likelihood of viral escape and limit spread of related viruses with pandemic potential. Here, we leveraged rational immunogen design to focus humoral responses on conserved epitopes. Using glycan engineering and epitope scaffolding, we directed murine serum antibody responses to conserved receptor binding motif (RBM) and domain (RBD) epitopes in the context of SARS-CoV-2 spike imprinting. Whereas all engineered immunogens elicited a robust SARS-CoV-2-neutralizing serum response, the RBM-focusing immunogens exhibited increased potency against related sarbecoviruses, SARS-CoV, WIV1-CoV, RaTG13-CoV, and SHC014-CoV;structural characterization of representative antibodies defined a conserved epitope. Furthermore, the RBM-focused sera conferred protection against SARS-CoV-2 challenge. Thus, RBM focusing is a promising strategy to elicit breadth across emerging sarbecoviruses without compromising SARS-CoV-2 protection. Broadly, these engineering strategies are adaptable to other viral glycoproteins for targeting conserved epitopes.

9.
Sci Immunol ; 6(64): eabj2901, 2021 Oct 15.
Article in English | MEDLINE | ID: covidwho-1470496

ABSTRACT

The introduction of vaccines has inspired hope in the battle against SARS-CoV-2. However, the emergence of viral variants, in the absence of potent antivirals, has left the world struggling with the uncertain nature of this disease. Antibodies currently represent the strongest correlate of immunity against SARS-CoV-2, thus we profiled the earliest humoral signatures in a large cohort of acutely ill (survivors and nonsurvivors) and mild or asymptomatic individuals with COVID-19. Although a SARS-CoV-2­specific immune response evolved rapidly in survivors of COVID-19, nonsurvivors exhibited blunted and delayed humoral immune evolution, particularly with respect to S2-specific antibodies. Given the conservation of S2 across ß-coronaviruses, we found that the early development of SARS-CoV-2­specific immunity occurred in tandem with preexisting common ß-coronavirus OC43 humoral immunity in survivors, which was also selectively expanded in individuals that develop a paucisymptomatic infection. These data point to the importance of cross-coronavirus immunity as a correlate of protection against COVID-19.


Subject(s)
COVID-19/immunology , Cross Reactions , Immunity, Humoral , SARS-CoV-2/immunology , Adolescent , Cohort Studies , Coronavirus OC43, Human/immunology , Disease Progression , Humans , Immunoglobulin Class Switching , Receptors, Fc/immunology , Spike Glycoprotein, Coronavirus/immunology , Survivors , Young Adult
10.
Sci Immunol ; 6(66): eabl5842, 2021 Dec 10.
Article in English | MEDLINE | ID: covidwho-1467664

ABSTRACT

Initial exposure to a pathogen elicits an adaptive immune response to control and eradicate the threat. Interrogating the abundance and specificity of the naive B cell repertoire drives understanding of how to mount protective responses. Here, we isolated naive B cells from eight seronegative human donors targeting the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor binding domain (RBD). Single-cell B cell receptor (BCR) sequencing identified diverse gene usage and no restriction on complementarity determining region length. A subset of recombinant antibodies produced by naive B cell precursors bound to SARS-CoV-2 RBD and engaged circulating variants including B.1.1.7, B.1.351, and B.1.617.2, as well as preemergent bat-derived coronaviruses RaTG13, SHC104, and WIV1. By structural characterization of a naive antibody in complex with SARS-CoV-2 spike, we identified a conserved mode of recognition shared with infection-induced antibodies. We found that representative naive antibodies could signal in a B cell activation assay, and by using directed evolution, we could select for a higher-affinity RBD interaction, conferred by a single amino acid change. The minimally mutated, affinity-matured antibodies also potently neutralized SARS-CoV-2. Understanding the SARS-CoV-2 RBD­specific naive repertoire may inform potential responses capable of recognizing future SARS-CoV-2 variants or emerging coronaviruses, enabling the development of pan-coronavirus vaccines aimed at engaging protective germline responses.


Subject(s)
B-Lymphocytes/cytology , B-Lymphocytes/immunology , Coronavirus/immunology , SARS-CoV-2/immunology , Antibodies, Neutralizing/immunology , Antigens, Viral/immunology , B-Lymphocytes/metabolism , COVID-19/immunology , COVID-19 Vaccines/immunology , Epitopes , Humans , Lymphocyte Activation , SARS-CoV-2/classification , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism
11.
PMC; 2020.
Preprint in English | PMC | ID: ppcovidwho-290515

ABSTRACT

We show that SARS-CoV-2 spike protein interacts with cell surface heparan sulfate and angiotensin converting enzyme 2 (ACE2) through its Receptor Binding Domain. Docking studies suggest a putative heparin/heparan sulfate-binding site adjacent to the domain that binds to ACE2. In vitro, binding of ACE2 and heparin to spike protein ectodomains occurs independently and a ternary complex can be generated using heparin as a template. Contrary to studies with purified components, spike protein binding to heparan sulfate and ACE2 on cells occurs codependently. Unfractionated heparin, non-anticoagulant heparin, treatment with heparin lyases, and purified lung heparan sulfate potently block spike protein binding and infection by spike protein-pseudotyped virus and SARS-CoV-2 virus. These findings support a model for SARS-CoV-2 infection in which viral attachment and infection involves formation of a complex between heparan sulfate and ACE2. Manipulation of heparan sulfate or inhibition of viral adhesion by exogenous heparin may represent new therapeutic opportunities. ### Competing Interest Statement J.D.E. is a co-founder of TEGA Therapeutics. J.D.E. and The Regents of the University of California have licensed a University invention to and have an equity interest in TEGA Therapeutics. The terms of this arrangement have been reviewed and approved by the University of California, San Diego in accordance with its conflict of interest policies. C.A.G and B.E.T are employees of TEGA Therapeutics.

12.
Cell Host Microbe ; 29(9): 1437-1453.e8, 2021 09 08.
Article in English | MEDLINE | ID: covidwho-1347535

ABSTRACT

The SARS-CoV-2 pandemic has affected more than 185 million people worldwide resulting in over 4 million deaths. To contain the pandemic, there is a continued need for safe vaccines that provide durable protection at low and scalable doses and can be deployed easily. Here, AAVCOVID-1, an adeno-associated viral (AAV), spike-gene-based vaccine candidate demonstrates potent immunogenicity in mouse and non-human primates following a single injection and confers complete protection from SARS-CoV-2 challenge in macaques. Peak neutralizing antibody titers are sustained at 1 year and complemented by functional memory T cell responses. The AAVCOVID vector has no relevant pre-existing immunity in humans and does not elicit cross-reactivity to common AAVs used in gene therapy. Vector genome persistence and expression wanes following injection. The single low-dose requirement, high-yield manufacturability, and 1-month stability for storage at room temperature may make this technology well suited to support effective immunization campaigns for emerging pathogens on a global scale.


Subject(s)
Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19 Vaccines/immunology , COVID-19/prevention & control , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/genetics , Dependovirus/genetics , Dependovirus/metabolism , Female , Humans , Immunogenicity, Vaccine/immunology , Immunologic Memory/immunology , Macaca fascicularis , Macaca mulatta , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , T-Lymphocytes/immunology , Transgenes/genetics , Vaccination/methods , Viral Load/immunology
13.
Cell ; 184(9): 2372-2383.e9, 2021 04 29.
Article in English | MEDLINE | ID: covidwho-1343151

ABSTRACT

Vaccination elicits immune responses capable of potently neutralizing SARS-CoV-2. However, ongoing surveillance has revealed the emergence of variants harboring mutations in spike, the main target of neutralizing antibodies. To understand the impact of these variants, we evaluated the neutralization potency of 99 individuals that received one or two doses of either BNT162b2 or mRNA-1273 vaccines against pseudoviruses representing 10 globally circulating strains of SARS-CoV-2. Five of the 10 pseudoviruses, harboring receptor-binding domain mutations, including K417N/T, E484K, and N501Y, were highly resistant to neutralization. Cross-neutralization of B.1.351 variants was comparable to SARS-CoV and bat-derived WIV1-CoV, suggesting that a relatively small number of mutations can mediate potent escape from vaccine responses. While the clinical impact of neutralization resistance remains uncertain, these results highlight the potential for variants to escape from neutralizing humoral immunity and emphasize the need to develop broadly protective interventions against the evolving pandemic.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19 Vaccines/immunology , Immunity, Humoral , SARS-CoV-2/immunology , COVID-19/blood , COVID-19/immunology , COVID-19/virology , HEK293 Cells , Humans , Mutation/genetics , ROC Curve , SARS-CoV-2/genetics
14.
ACS Cent Sci ; 7(7): 1156-1165, 2021 Jul 28.
Article in English | MEDLINE | ID: covidwho-1337094

ABSTRACT

As the COVID-19 pandemic continues to spread, investigating the processes underlying the interactions between SARS-CoV-2 and its hosts is of high importance. Here, we report the identification of CD209L/L-SIGN and the related protein CD209/DC-SIGN as receptors capable of mediating SARS-CoV-2 entry into human cells. Immunofluorescence staining of human tissues revealed prominent expression of CD209L in the lung and kidney epithelia and endothelia. Multiple biochemical assays using a purified recombinant SARS-CoV-2 spike receptor-binding domain (S-RBD) or S1 encompassing both N termal domain and RBD and ectopically expressed CD209L and CD209 revealed that CD209L and CD209 interact with S-RBD. CD209L contains two N-glycosylation sequons, at sites N92 and N361, but we determined that only site N92 is occupied. Removal of the N-glycosylation at this site enhances the binding of S-RBD with CD209L. CD209L also interacts with ACE2, suggesting a role for heterodimerization of CD209L and ACE2 in SARS-CoV-2 entry and infection in cell types where both are present. Furthermore, we demonstrate that human endothelial cells are permissive to SARS-CoV-2 infection, and interference with CD209L activity by a knockdown strategy or with soluble CD209L inhibits virus entry. Our observations demonstrate that CD209L and CD209 serve as alternative receptors for SARS-CoV-2 in disease-relevant cell types, including the vascular system. This property is particularly important in tissues where ACE2 has low expression or is absent and may have implications for antiviral drug development.

15.
Cell ; 184(19): 4969-4980.e15, 2021 09 16.
Article in English | MEDLINE | ID: covidwho-1333275

ABSTRACT

Memory B cell reserves can generate protective antibodies against repeated SARS-CoV-2 infections, but with unknown reach from original infection to antigenically drifted variants. We charted memory B cell receptor-encoded antibodies from 19 COVID-19 convalescent subjects against SARS-CoV-2 spike (S) and found seven major antibody competition groups against epitopes recurrently targeted across individuals. Inclusion of published and newly determined structures of antibody-S complexes identified corresponding epitopic regions. Group assignment correlated with cross-CoV-reactivity breadth, neutralization potency, and convergent antibody signatures. Although emerging SARS-CoV-2 variants of concern escaped binding by many members of the groups associated with the most potent neutralizing activity, some antibodies in each of those groups retained affinity-suggesting that otherwise redundant components of a primary immune response are important for durable protection from evolving pathogens. Our results furnish a global atlas of S-specific memory B cell repertoires and illustrate properties driving viral escape and conferring robustness against emerging variants.

16.
JAMA ; 325(23): 2370-2380, 2021 06 15.
Article in English | MEDLINE | ID: covidwho-1287297

ABSTRACT

Importance: Pregnant women are at increased risk of morbidity and mortality from COVID-19 but have been excluded from the phase 3 COVID-19 vaccine trials. Data on vaccine safety and immunogenicity in these populations are therefore limited. Objective: To evaluate the immunogenicity of COVID-19 messenger RNA (mRNA) vaccines in pregnant and lactating women, including against emerging SARS-CoV-2 variants of concern. Design, Setting, and Participants: An exploratory, descriptive, prospective cohort study enrolled 103 women who received a COVID-19 vaccine from December 2020 through March 2021 and 28 women who had confirmed SARS-CoV-2 infection from April 2020 through March 2021 (the last follow-up date was March 26, 2021). This study enrolled 30 pregnant, 16 lactating, and 57 neither pregnant nor lactating women who received either the mRNA-1273 (Moderna) or BNT162b2 (Pfizer-BioNTech) COVID-19 vaccines and 22 pregnant and 6 nonpregnant unvaccinated women with SARS-CoV-2 infection. Main Outcomes and Measures: SARS-CoV-2 receptor binding domain binding, neutralizing, and functional nonneutralizing antibody responses from pregnant, lactating, and nonpregnant women were assessed following vaccination. Spike-specific T-cell responses were evaluated using IFN-γ enzyme-linked immunospot and multiparameter intracellular cytokine-staining assays. Humoral and cellular immune responses were determined against the original SARS-CoV-2 USA-WA1/2020 strain as well as against the B.1.1.7 and B.1.351 variants. Results: This study enrolled 103 women aged 18 to 45 years (66% non-Hispanic White) who received a COVID-19 mRNA vaccine. After the second vaccine dose, fever was reported in 4 pregnant women (14%; SD, 6%), 7 lactating women (44%; SD, 12%), and 27 nonpregnant women (52%; SD, 7%). Binding, neutralizing, and functional nonneutralizing antibody responses as well as CD4 and CD8 T-cell responses were present in pregnant, lactating, and nonpregnant women following vaccination. Binding and neutralizing antibodies were also observed in infant cord blood and breast milk. Binding and neutralizing antibody titers against the SARS-CoV-2 B.1.1.7 and B.1.351 variants of concern were reduced, but T-cell responses were preserved against viral variants. Conclusion and Relevance: In this exploratory analysis of a convenience sample, receipt of a COVID-19 mRNA vaccine was immunogenic in pregnant women, and vaccine-elicited antibodies were transported to infant cord blood and breast milk. Pregnant and nonpregnant women who were vaccinated developed cross-reactive antibody responses and T-cell responses against SARS-CoV-2 variants of concern.


Subject(s)
Antibodies, Viral/blood , COVID-19 Vaccines/immunology , COVID-19/immunology , Fetal Blood/immunology , Immunogenicity, Vaccine , Milk, Human/immunology , SARS-CoV-2/immunology , Adult , Antibodies, Neutralizing/blood , Cross Reactions/immunology , Female , Humans , Immunoassay , Lactation , Leukocytes, Mononuclear/physiology , Middle Aged , Pregnancy/immunology , Prospective Studies , T-Lymphocytes/immunology , Vaccines, Synthetic/immunology , Young Adult
17.
Nat Chem Biol ; 17(10): 1057-1064, 2021 10.
Article in English | MEDLINE | ID: covidwho-1281726

ABSTRACT

The predominant approach for antibody generation remains animal immunization, which can yield exceptionally selective and potent antibody clones owing to the powerful evolutionary process of somatic hypermutation. However, animal immunization is inherently slow, not always accessible and poorly compatible with many antigens. Here, we describe 'autonomous hypermutation yeast surface display' (AHEAD), a synthetic recombinant antibody generation technology that imitates somatic hypermutation inside engineered yeast. By encoding antibody fragments on an error-prone orthogonal DNA replication system, surface-displayed antibody repertoires continuously mutate through simple cycles of yeast culturing and enrichment for antigen binding to produce high-affinity clones in as little as two weeks. We applied AHEAD to generate potent nanobodies against the SARS-CoV-2 S glycoprotein, a G-protein-coupled receptor and other targets, offering a template for streamlined antibody generation at large.


Subject(s)
Antibody Formation/immunology , Protein Engineering/methods , Recombinant Proteins/biosynthesis , Antibodies/immunology , Antigens , COVID-19/immunology , Humans , Peptide Library , Recombinant Proteins/metabolism , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Saccharomyces cerevisiae/metabolism , Single-Domain Antibodies/genetics , Single-Domain Antibodies/metabolism , Spike Glycoprotein, Coronavirus/immunology
18.
Cell ; 184(16): 4203-4219.e32, 2021 08 05.
Article in English | MEDLINE | ID: covidwho-1275187

ABSTRACT

SARS-CoV-2-neutralizing antibodies (NAbs) protect against COVID-19. A concern regarding SARS-CoV-2 antibodies is whether they mediate disease enhancement. Here, we isolated NAbs against the receptor-binding domain (RBD) or the N-terminal domain (NTD) of SARS-CoV-2 spike from individuals with acute or convalescent SARS-CoV-2 or a history of SARS-CoV infection. Cryo-electron microscopy of RBD and NTD antibodies demonstrated function-specific modes of binding. Select RBD NAbs also demonstrated Fc receptor-γ (FcγR)-mediated enhancement of virus infection in vitro, while five non-neutralizing NTD antibodies mediated FcγR-independent in vitro infection enhancement. However, both types of infection-enhancing antibodies protected from SARS-CoV-2 replication in monkeys and mice. Three of 46 monkeys infused with enhancing antibodies had higher lung inflammation scores compared to controls. One monkey had alveolar edema and elevated bronchoalveolar lavage inflammatory cytokines. Thus, while in vitro antibody-enhanced infection does not necessarily herald enhanced infection in vivo, increased lung inflammation can rarely occur in SARS-CoV-2 antibody-infused macaques.


Subject(s)
Antibodies, Neutralizing/immunology , SARS-CoV-2/physiology , Spike Glycoprotein, Coronavirus/immunology , Animals , Antibodies, Viral/immunology , Bronchoalveolar Lavage Fluid/chemistry , COVID-19/pathology , COVID-19/virology , Cytokines/metabolism , Female , Haplorhini , Humans , Lung/pathology , Lung/virology , Male , Mice , Mice, Inbred BALB C , Protein Domains , RNA, Guide/metabolism , Receptors, IgG/metabolism , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/chemistry , Viral Load , Virus Replication
19.
JAMA ; 325(23): 2370-2380, 2021 06 15.
Article in English | MEDLINE | ID: covidwho-1226170

ABSTRACT

Importance: Pregnant women are at increased risk of morbidity and mortality from COVID-19 but have been excluded from the phase 3 COVID-19 vaccine trials. Data on vaccine safety and immunogenicity in these populations are therefore limited. Objective: To evaluate the immunogenicity of COVID-19 messenger RNA (mRNA) vaccines in pregnant and lactating women, including against emerging SARS-CoV-2 variants of concern. Design, Setting, and Participants: An exploratory, descriptive, prospective cohort study enrolled 103 women who received a COVID-19 vaccine from December 2020 through March 2021 and 28 women who had confirmed SARS-CoV-2 infection from April 2020 through March 2021 (the last follow-up date was March 26, 2021). This study enrolled 30 pregnant, 16 lactating, and 57 neither pregnant nor lactating women who received either the mRNA-1273 (Moderna) or BNT162b2 (Pfizer-BioNTech) COVID-19 vaccines and 22 pregnant and 6 nonpregnant unvaccinated women with SARS-CoV-2 infection. Main Outcomes and Measures: SARS-CoV-2 receptor binding domain binding, neutralizing, and functional nonneutralizing antibody responses from pregnant, lactating, and nonpregnant women were assessed following vaccination. Spike-specific T-cell responses were evaluated using IFN-γ enzyme-linked immunospot and multiparameter intracellular cytokine-staining assays. Humoral and cellular immune responses were determined against the original SARS-CoV-2 USA-WA1/2020 strain as well as against the B.1.1.7 and B.1.351 variants. Results: This study enrolled 103 women aged 18 to 45 years (66% non-Hispanic White) who received a COVID-19 mRNA vaccine. After the second vaccine dose, fever was reported in 4 pregnant women (14%; SD, 6%), 7 lactating women (44%; SD, 12%), and 27 nonpregnant women (52%; SD, 7%). Binding, neutralizing, and functional nonneutralizing antibody responses as well as CD4 and CD8 T-cell responses were present in pregnant, lactating, and nonpregnant women following vaccination. Binding and neutralizing antibodies were also observed in infant cord blood and breast milk. Binding and neutralizing antibody titers against the SARS-CoV-2 B.1.1.7 and B.1.351 variants of concern were reduced, but T-cell responses were preserved against viral variants. Conclusion and Relevance: In this exploratory analysis of a convenience sample, receipt of a COVID-19 mRNA vaccine was immunogenic in pregnant women, and vaccine-elicited antibodies were transported to infant cord blood and breast milk. Pregnant and nonpregnant women who were vaccinated developed cross-reactive antibody responses and T-cell responses against SARS-CoV-2 variants of concern.


Subject(s)
Antibodies, Viral/blood , COVID-19 Vaccines/immunology , COVID-19/immunology , Fetal Blood/immunology , Immunogenicity, Vaccine , Milk, Human/immunology , SARS-CoV-2/immunology , Adult , Antibodies, Neutralizing/blood , Cross Reactions/immunology , Female , Humans , Immunoassay , Lactation , Leukocytes, Mononuclear/physiology , Middle Aged , Pregnancy/immunology , Prospective Studies , T-Lymphocytes/immunology , Vaccines, Synthetic/immunology , Young Adult
20.
J Virol ; 2021 Mar 10.
Article in English | MEDLINE | ID: covidwho-1127540

ABSTRACT

Vaccines are being rapidly developed with the goal of ending the SARS-CoV-2 pandemic. However, the extent to which SARS-CoV-2 vaccination induces serum responses that cross-react with other coronaviruses remains poorly studied. Here we define serum profiles in rhesus macaques after vaccination with DNA or Ad26 based vaccines expressing SARS-CoV-2 Spike protein followed by SARS-CoV-2 challenge, or SARS-CoV-2 infection alone. Analysis of serum responses showed robust reactivity to the SARS-CoV-2 full-length Spike protein and receptor binding domain (RBD), both included in the vaccine. However, serum cross-reactivity to the closely related sarbecovirus SARS-CoV-1 Spike and RBD, was reduced. Reactivity was also measured to the distantly related common cold alpha-coronavirus, 229E and NL63, and beta-coronavirus, OC43 and HKU1, Spike proteins. Using SARS-COV-2 and SARS-CoV-1 lentivirus based pseudoviruses, we show that neutralizing antibody responses were predominantly SARS-CoV-2 specific. These data define patterns of cross-reactive binding and neutralizing serum responses induced by SARS-CoV-2 infection and vaccination in rhesus macaques. Our observations have important implications for understanding polyclonal responses to SARS-CoV-2 Spike, which will facilitate future CoV vaccine assessment and development.ImportanceThe rapid development and deployment of SARS-CoV-2 vaccines has been unprecedented. In this study, we explore the cross-reactivity of SARS-CoV-2 specific antibody responses to other coronaviruses. By analyzing responses from NHPs both before and after immunization with DNA or Ad26 vectored vaccines, we find patterns of cross reactivity that mirror those induced by SARS-CoV-2 infection. These data highlight the similarities between infection and vaccine induced humoral immunity for SARS-CoV-2 and cross-reactivity of these responses to other CoVs.

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