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2.
Proc Natl Acad Sci U S A ; 119(34): e2204256119, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35972965

RESUMO

Antibody therapeutics for the treatment of COVID-19 have been highly successful. However, the recent emergence of the Omicron variant has posed a challenge, as it evades detection by most existing SARS-CoV-2 neutralizing antibodies (nAbs). Here, we successfully generated a panel of SARS-CoV-2/SARS-CoV cross-neutralizing antibodies by sequential immunization of the two pseudoviruses. Of the potential candidates, we found that nAbs X01, X10, and X17 offer broad neutralizing potential against most variants of concern, with X17 further identified as a Class 5 nAb with undiminished neutralization against the Omicron variant. Cryo-electron microscopy structures of the three antibodies together in complex with each of the spike proteins of the prototypical SARS-CoV, SARS-CoV-2, and Delta and Omicron variants of SARS-CoV-2 defined three nonoverlapping conserved epitopes on the receptor-binding domain. The triple-antibody mixture exhibited enhanced resistance to viral evasion and effective protection against infection of the Beta variant in hamsters. Our findings will aid the development of antibody therapeutics and broad vaccines against SARS-CoV-2 and its emerging variants.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos , Vírus da SARS , SARS-CoV-2 , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , Sequência Conservada , Cricetinae , Microscopia Crioeletrônica , Epitopos/imunologia , Humanos , Camundongos , Testes de Neutralização , Vírus da SARS/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética
3.
Proc Natl Acad Sci U S A ; 119(35): e2110105119, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35994646

RESUMO

The spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the main target for neutralizing antibodies (NAbs). The S protein trimer is anchored in the virion membrane in its prefusion (preS) but metastable form. The preS protein has been stabilized by introducing two or six proline substitutions, to generate stabilized, soluble 2P or HexaPro (6P) preS proteins. Currently, it is not known which form is the most immunogenic. Here, we generated recombinant vesicular stomatitis virus (rVSV) expressing preS-2P, preS-HexaPro, and native full-length S, and compared their immunogenicity in mice and hamsters. The rVSV-preS-HexaPro produced and secreted significantly more preS protein compared to rVSV-preS-2P. Importantly, rVSV-preS-HexaPro triggered significantly more preS-specific serum IgG antibody than rVSV-preS-2P in both mice and hamsters. Antibodies induced by preS-HexaPro neutralized the B.1.1.7, B.1.351, P.1, B.1.427, and B.1.617.2 variants approximately two to four times better than those induced by preS-2P. Furthermore, preS-HexaPro induced a more robust Th1-biased cellular immune response than preS-2P. A single dose (104 pfu) immunization with rVSV-preS-HexaPro and rVSV-preS-2P provided complete protection against challenge with mouse-adapted SARS-CoV-2 and B.1.617.2 variant, whereas rVSV-S only conferred partial protection. When the immunization dose was lowered to 103 pfu, rVSV-preS-HexaPro induced two- to sixfold higher antibody responses than rVSV-preS-2P in hamsters. In addition, rVSV-preS-HexaPro conferred 70% protection against lung infection whereas only 30% protection was observed in the rVSV-preS-2P. Collectively, our data demonstrate that both preS-2P and preS-HexaPro are highly efficacious but preS-HexaPro is more immunogenic and protective, highlighting the advantages of using preS-HexaPro in the next generation of SARS-CoV-2 vaccines.


Assuntos
Prolina , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Desenvolvimento de Vacinas , Estomatite Vesicular , Vacinas Virais , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/genética , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Vacinas contra COVID-19/imunologia , Cricetinae , Humanos , Camundongos , Prolina/imunologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Estomatite Vesicular/imunologia , Estomatite Vesicular/prevenção & controle , Estomatite Vesicular/virologia , Vesiculovirus/imunologia , Proteínas Virais/imunologia , Vacinas Virais/imunologia
4.
Theranostics ; 12(12): 5522-5536, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910791

RESUMO

Objective: Nobody knows when the COVID-19 pandemic will end or when and where the next coronavirus will outbreak. Therefore, it is still necessary to develop SARS-CoV-2 inhibitors for different variants or even the new coronavirus. Since SARS-CoV-2 uses its surface spike-protein to recognize hACE2, mediating its entry into cells, ligands that can specifically recognize the spike-protein have the potential to prevent infection. Methods: We have recently discovered DNA aptamers against the S2-domain of the WT spike-protein by exploiting the selection process called SELEX. After optimization, among all candidates, the aptamer S2A2C1 has the shortest sequence and the best binding affinity toward the S2-protein. More importantly, the S2A2C1 aptamer does not bind to the RBD of the spike-protein, but it efficiently blocks the spike-protein/hACE2 interaction, suggesting an RBD-independent inhibition approach. To further improve its performance, we conjugated the S2A2C1 aptamer with a reported anti-RBD aptamer, S1B6C3, using various linkers and constructed hetero-bivalent fusion aptamers. Binding affinities of mono and fusion aptamers against the spike-proteins were measured. The inhibition efficacies of mono and fusion aptamers to prevent the hACE2/spike-protein interaction were determined using ELISA. Results: Anti-spike-protein aptamers, including S2A2C1 and S1B6C3-A5-S2A2C1, maintained high binding affinity toward the WT, Delta, and Omicron spike-proteins and high inhibition efficacies to prevent them from binding to hACE2, rendering them well-suited as diagnostic and therapeutic molecular tools to target SARS-CoV-2 and its variants. Conclusions: Overall, we discovered the anti-S2 aptamer, S2A2C1, which inhibits the hACE2/spike-protein interaction via an RBD-independent approach. The anti-S2 and anti-RBD aptamers were conjugated to obtain the fusion aptamer, S1B6C3-A5-S2A2C1, which recognizes the spike-protein by an RBD-dependent approach. Our strategies, which discovered aptamer inhibitors targeting the highly conserved S2-protein, as well as the design of fusion aptamers, can be used to target new coronaviruses as they emerge.


Assuntos
Enzima de Conversão de Angiotensina 2 , Aptâmeros de Nucleotídeos , COVID-19 , Glicoproteína da Espícula de Coronavírus , Enzima de Conversão de Angiotensina 2/imunologia , Anticorpos Neutralizantes/imunologia , Aptâmeros de Nucleotídeos/imunologia , Aptâmeros de Nucleotídeos/farmacologia , COVID-19/imunologia , COVID-19/virologia , Humanos , Pandemias , Peptidil Dipeptidase A/metabolismo , Ligação Proteica , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
5.
J Virol ; 96(17): e0011822, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-35972290

RESUMO

SARS-CoV-2 has mutated frequently since its first emergence in 2019. Numerous variants, including the currently emerging Omicron variant, have demonstrated high transmissibility or increased disease severity, posing serious threats to global public health. This study describes the identification of an immunodominant non-neutralizing epitope on SARS-CoV-2 receptor-binding domain (RBD). A subunit vaccine against this mutant RBD, constructed by masking this epitope with a glycan probe, did not significantly affect RBD's receptor-binding affinity or antibody-binding affinity, or its ability to induce antibody production. However, this vaccine enhanced the neutralizing activity of this RBD and its protective efficacy in immunized mice. Specifically, this vaccine elicited significantly higher-titer neutralizing antibodies than the prototypic RBD protein against Alpha (B.1.1.7 lineage), Beta (B.1.351 lineage), Gamma (P.1 lineage), and Epsilon (B.1.427 or B.1.429 lineage) variant pseudoviruses containing single or combined mutations in the spike (S) protein, albeit the neutralizing antibody titers against some variants were slightly lower than against original SARS-CoV-2. This vaccine also significantly improved the neutralizing activity of the prototypic RBD against pseudotyped and authentic Delta (B.1.617.2 lineage) and Omicron (B.1.1.529 lineage) variants, although the neutralizing antibody titers were lower than against original SARS-CoV-2. In contrast to the prototypic RBD, the mutant RBD completely protected human ACE2 (hACE2)-transgenic mice from lethal challenge with a prototype SARS-CoV-2 strain and a Delta variant without weight loss. Overall, these findings indicate that this RBD vaccine has broad-spectrum activity against multiple SARS-CoV-2 variants, as well as the potential to be effective and have improved efficacy against Omicron and other pandemic variants. IMPORTANCE Several SARS-CoV-2 variants have shown increased transmissibility, calling for a need to develop effective vaccines with broadly neutralizing activity against multiple variants. This study identified a non-neutralizing epitope on the receptor-binding domain (RBD) of SARS-CoV-2 spike protein, and further shielded it with a glycan probe. A subunit vaccine based on this mutant RBD significantly enhanced the ability of prototypic RBD against multiple SARS-CoV-2 variants, including the Delta and Omicron strains, although the neutralizing antibody titers against some of these variants were lower than those against original SARS-CoV-2. This mutant vaccine also enhanced the protective efficacy of the prototypic RBD vaccine against SARS-CoV-2 infection in immunized animals. In conclusion, this study identified an engineered RBD vaccine against Omicron and other SARS-CoV-2 variants that induced stronger neutralizing antibodies and protection than the original RBD vaccine. It also highlights the need to improve the effectiveness of current COVID-19 vaccines to prevent pandemic SARS-CoV-2 variants.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Epitopos , Glicosilação , Humanos , Camundongos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química , Vacinas de Subunidades/imunologia
6.
Science ; 377(6606): eabq0839, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35857620

RESUMO

To combat future severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants and spillovers of SARS-like betacoronaviruses (sarbecoviruses) threatening global health, we designed mosaic nanoparticles that present randomly arranged sarbecovirus spike receptor-binding domains (RBDs) to elicit antibodies against epitopes that are conserved and relatively occluded rather than variable, immunodominant, and exposed. We compared immune responses elicited by mosaic-8 (SARS-CoV-2 and seven animal sarbecoviruses) and homotypic (only SARS-CoV-2) RBD nanoparticles in mice and macaques and observed stronger responses elicited by mosaic-8 to mismatched (not on nanoparticles) strains, including SARS-CoV and animal sarbecoviruses. Mosaic-8 immunization showed equivalent neutralization of SARS-CoV-2 variants, including Omicrons, and protected from SARS-CoV-2 and SARS-CoV challenges, whereas homotypic SARS-CoV-2 immunization protected only from SARS-CoV-2 challenge. Epitope mapping demonstrated increased targeting of conserved epitopes after mosaic-8 immunization. Together, these results suggest that mosaic-8 RBD nanoparticles could protect against SARS-CoV-2 variants and future sarbecovirus spillovers.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Betacoronavirus , Infecções por Coronavirus , Epitopos , Nanopartículas , Glicoproteína da Espícula de Coronavírus , Zoonoses , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Modelos Animais de Doenças , Epitopos/química , Epitopos/imunologia , Epitopos/uso terapêutico , Macaca , Camundongos , Nanopartículas/uso terapêutico , Domínios Proteicos/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Zoonoses/prevenção & controle , Zoonoses/virologia
8.
Science ; 377(6608): 890-894, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35857529

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant of concern comprises several sublineages, with BA.2 and BA.2.12.1 having replaced the previously dominant BA.1 and with BA.4 and BA.5 increasing in prevalence worldwide. We show that the large number of Omicron sublineage spike mutations leads to enhanced angiotensin-converting enzyme 2 (ACE2) binding, reduced fusogenicity, and severe dampening of plasma neutralizing activity elicited by infection or seven clinical vaccines relative to the ancestral virus. Administration of a homologous or heterologous booster based on the Wuhan-Hu-1 spike sequence markedly increased neutralizing antibody titers and breadth against BA.1, BA.2, BA.2.12.1, BA.4, and BA.5 across all vaccines evaluated. Our data suggest that although Omicron sublineages evade polyclonal neutralizing antibody responses elicited by primary vaccine series, vaccine boosters may provide sufficient protection against Omicron-induced severe disease.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , COVID-19/sangue , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Humanos , Imunização Secundária , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia
9.
Nature ; 608(7923): 603-608, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35790190

RESUMO

SARS-CoV-2 Omicron subvariants BA.2.12.1 and BA.4/5 have surged notably to become dominant in the United States and South Africa, respectively1,2. These new subvariants carrying further mutations in their spike proteins raise concerns that they may further evade neutralizing antibodies, thereby further compromising the efficacy of COVID-19 vaccines and therapeutic monoclonals. We now report findings from a systematic antigenic analysis of these surging Omicron subvariants. BA.2.12.1 is only modestly (1.8-fold) more resistant to sera from vaccinated and boosted individuals than BA.2. However, BA.4/5 is substantially (4.2-fold) more resistant and thus more likely to lead to vaccine breakthrough infections. Mutation at spike residue L452 found in both BA.2.12.1 and BA.4/5 facilitates escape from some antibodies directed to the so-called class 2 and 3 regions of the receptor-binding domain3. The F486V mutation found in BA.4/5 facilitates escape from certain class 1 and 2 antibodies but compromises the spike affinity for the viral receptor. The R493Q reversion mutation, however, restores receptor affinity and consequently the fitness of BA.4/5. Among therapeutic antibodies authorized for clinical use, only bebtelovimab retains full potency against both BA.2.12.1 and BA.4/5. The Omicron lineage of SARS-CoV-2 continues to evolve, successively yielding subvariants that are not only more transmissible but also more evasive to antibodies.


Assuntos
Anticorpos Antivirais , Deriva e Deslocamento Antigênicos , COVID-19 , Mutação , SARS-CoV-2 , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/uso terapêutico , Deriva e Deslocamento Antigênicos/genética , Deriva e Deslocamento Antigênicos/imunologia , COVID-19/imunologia , COVID-19/virologia , Vacinas contra COVID-19/imunologia , Humanos , Imunização Secundária , Receptores Virais/metabolismo , SARS-CoV-2/classificação , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo
10.
PLoS Pathog ; 18(7): e1010686, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35862442

RESUMO

Successful control of the COVID-19 pandemic depends on vaccines that prevent transmission. The full-length Spike protein is highly immunogenic but the majority of antibodies do not target the virus: ACE2 interface. In an effort to affect the quality of the antibody response focusing it to the receptor-binding motif (RBM) we generated a series of conformationally-constrained immunogens by inserting solvent-exposed RBM amino acid residues into hypervariable loops of an immunoglobulin molecule. Priming C57BL/6 mice with plasmid (p)DNA encoding these constructs yielded a rapid memory response to booster immunization with recombinant Spike protein. Immune sera antibodies bound strongly to the purified receptor-binding domain (RBD) and Spike proteins. pDNA primed for a consistent response with antibodies efficient at neutralizing authentic WA1 virus and three variants of concern (VOC), B.1.351, B.1.617.2, and BA.1. We demonstrate that immunogens built on structure selection can be used to influence the quality of the antibody response by focusing it to a conserved site of vulnerability shared between wildtype virus and VOCs, resulting in neutralizing antibodies across variants.


Assuntos
Anticorpos Neutralizantes , COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais , COVID-19/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Pandemias/prevenção & controle , Glicoproteína da Espícula de Coronavírus/imunologia
11.
J Virol ; 96(15): e0055822, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35867572

RESUMO

As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to evolve, several variants of concern (VOCs) have arisen which are defined by multiple mutations in their spike proteins. These VOCs have shown variable escape from antibody responses and have been shown to trigger qualitatively different antibody responses during infection. By studying plasma from individuals infected with either the original D614G, Beta, or Delta variants, we showed that the Beta and Delta variants elicit antibody responses that are overall more cross-reactive than those triggered by D614G. Patterns of cross-reactivity varied, and the Beta and Delta variants did not elicit cross-reactive responses to each other. However, Beta-elicited plasma was highly cross-reactive against Delta Plus (Delta+), which differs from Delta by a single K417N mutation in the receptor binding domain, suggesting that the plasma response targets the N417 residue. To probe this further, we isolated monoclonal antibodies from a Beta-infected individual with plasma responses against Beta, Delta+, and Omicron, which all possess the N417 residue. We isolated an N417-dependent antibody, 084-7D, which showed similar neutralization breadth to the plasma. The 084-7D MAb utilized the IGHV3-23*01 germ line gene and had somatic hypermutations similar to those of previously described public antibodies which target the 417 residue. Thus, we have identified a novel antibody which targets a shared epitope found on three distinct VOCs, enabling their cross-neutralization. Understanding antibodies targeting escape mutations, such as K417N, which repeatedly emerge through convergent evolution in SARS-CoV-2 variants, may aid in the development of next-generation antibody therapeutics and vaccines. IMPORTANCE The evolution of SARS-CoV-2 has resulted in variants of concern (VOCs) with distinct spike mutations conferring various immune escape profiles. These variable mutations also influence the cross-reactivity of the antibody response mounted by individuals infected with each of these variants. This study sought to understand the antibody responses elicited by different SARS-CoV-2 variants and to define shared epitopes. We show that Beta and Delta infections resulted in antibody responses that were more cross-reactive than the original D614G variant, but they had differing patterns of cross-reactivity. We further isolated an antibody from Beta infection which targeted the N417 site, enabling cross-neutralization of Beta, Delta+, and Omicron, all of which possess this residue. The discovery of antibodies which target escape mutations common to multiple variants highlights conserved epitopes to target in future vaccines and therapeutics.


Assuntos
Anticorpos Antivirais , Reações Cruzadas , Epitopos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/virologia , Reações Cruzadas/imunologia , Epitopos/química , Epitopos/genética , Epitopos/imunologia , Humanos , Evasão da Resposta Imune/imunologia , Testes de Neutralização , SARS-CoV-2/química , SARS-CoV-2/classificação , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia
12.
J Mol Biol ; 434(17): 167717, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35798162

RESUMO

Allosteric proteins transition between 'inactive' and 'active' states. In general, such proteins assume distinct conformational states at the level of secondary, tertiary and/or quaternary structure. Different conformers of an allosteric protein can be antigenically dissimilar and induce antibodies with a highly distinctive specificities and neutralizing functional effects. Here we summarize studies on various functional types of monoclonal antibodies obtained against different allosteric conformers of the mannose-specific bacterial adhesin FimH - the most common cell attachment protein of Escherichia coli and other enterobacterial pathogens. Included are types of antibodies that activate the FimH function via interaction with ligand-induced binding sites or by wedging between domains as well as antibodies that inhibit FimH through orthosteric, parasteric, or novel dynasteric mechanisms. Understanding the molecular mechanism of antibody action against allosteric proteins provides insights on how to design antibodies with a desired functional effect, including those with neutralizing activity against bacterial and viral cell attachment proteins.


Assuntos
Adesinas de Escherichia coli , Anticorpos Neutralizantes , Proteínas de Fímbrias , Adesinas de Escherichia coli/química , Adesinas de Escherichia coli/imunologia , Regulação Alostérica , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/imunologia , Proteínas de Fímbrias/química , Proteínas de Fímbrias/imunologia , Conformação Proteica
13.
Proc Natl Acad Sci U S A ; 119(31): e2200592119, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35858386

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant contains extensive sequence changes relative to the earlier-arising B.1, B.1.1, and Delta SARS-CoV-2 variants that have unknown effects on viral infectivity and response to existing vaccines. Using SARS-CoV-2 virus-like particles (VLPs), we examined mutations in all four structural proteins and found that Omicron and Delta showed 4.6-fold higher luciferase delivery overall relative to the ancestral B.1 lineage, a property conferred mostly by enhancements in the S and N proteins, while mutations in M and E were mostly detrimental to assembly. Thirty-eight antisera samples from individuals vaccinated with Pfizer/BioNTech, Moderna, or Johnson & Johnson vaccines and convalescent sera from unvaccinated COVID-19 survivors had 15-fold lower efficacy to prevent cell transduction by VLPs containing the Omicron mutations relative to the ancestral B.1 spike protein. A third dose of Pfizer vaccine elicited substantially higher neutralization titers against Omicron, resulting in detectable neutralizing antibodies in eight out of eight subjects compared to one out of eight preboosting. Furthermore, the monoclonal antibody therapeutics casirivimab and imdevimab had robust neutralization activity against B.1 and Delta VLPs but no detectable neutralization of Omicron VLPs, while newly authorized bebtelovimab maintained robust neutralization across variants. Our results suggest that Omicron has similar assembly efficiency and cell entry compared to Delta and that its rapid spread is due mostly to reduced neutralization in sera from previously vaccinated subjects. In addition, most currently available monoclonal antibodies will not be useful in treating Omicron-infected patients with the exception of bebtelovimab.


Assuntos
Anticorpos Monoclonais Humanizados , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/uso terapêutico , COVID-19/terapia , COVID-19/virologia , Humanos , Mutação , SARS-CoV-2/genética , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/genética
14.
Med (N Y) ; 3(7): 468-480.e5, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35716665

RESUMO

BACKGROUND: Much remains unknown regarding the response of the immune system to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccination. METHODS: We employed circulating cell-free DNA (cfDNA) to assess the turnover of specific immune cell types following administration of the Pfizer/BioNTech vaccine. FINDINGS: The levels of B cell cfDNA after the primary dose correlated with development of neutralizing antibodies and memory B cells after the booster, revealing a link between early B cell turnover-potentially reflecting affinity maturation-and later development of effective humoral response. We also observed co-elevation of B cell, T cell, and monocyte cfDNA after the booster, underscoring the involvement of innate immune cell turnover in the development of humoral and cellular adaptive immunity. Actual cell counts remained largely stable following vaccination, other than a previously demonstrated temporary reduction in neutrophil and lymphocyte counts. CONCLUSIONS: Immune cfDNA dynamics reveal the crucial role of the primary SARS-CoV-2 vaccine in shaping responses of the immune system following the booster vaccine. FUNDING: This work was supported by a generous gift from Shlomo Kramer. Supported by grants from Human Islet Research Network (HIRN UC4DK116274 and UC4DK104216 to R.S. and Y.D.), Ernest and Bonnie Beutler Research Program of Excellence in Genomic Medicine, The Alex U Soyka Pancreatic Cancer Fund, The Israel Science Foundation, the Waldholtz/Pakula family, the Robert M. and Marilyn Sternberg Family Charitable Foundation, the Helmsley Charitable Trust, Grail, and the DON Foundation (to Y.D.). Y.D. holds the Walter and Greta Stiel Chair and Research Grant in Heart Studies. I.F.-F. received a fellowship from the Glassman Hebrew University Diabetes Center.


Assuntos
Vacina BNT162 , COVID-19 , Ácidos Nucleicos Livres , SARS-CoV-2 , Adulto , Idoso , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/genética , Anticorpos Antivirais/imunologia , Vacina BNT162/administração & dosagem , COVID-19/imunologia , COVID-19/prevenção & controle , Ácidos Nucleicos Livres/genética , Ácidos Nucleicos Livres/imunologia , Feminino , Humanos , Imunização Secundária , Masculino , Células B de Memória/imunologia , Células B de Memória/metabolismo , Pessoa de Meia-Idade , SARS-CoV-2/imunologia , Adulto Jovem
15.
Nature ; 606(7913): 375-381, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35650437

RESUMO

Antiretroviral therapy is highly effective in suppressing human immunodeficiency virus (HIV)1. However, eradication of the virus in individuals with HIV has not been possible to date2. Given that HIV suppression requires life-long antiretroviral therapy, predominantly on a daily basis, there is a need to develop clinically effective alternatives that use long-acting antiviral agents to inhibit viral replication3. Here we report the results of a two-component clinical trial involving the passive transfer of two HIV-specific broadly neutralizing monoclonal antibodies, 3BNC117 and 10-1074. The first component was a randomized, double-blind, placebo-controlled trial that enrolled participants who initiated antiretroviral therapy during the acute/early phase of HIV infection. The second component was an open-label single-arm trial that enrolled individuals with viraemic control who were naive to antiretroviral therapy. Up to 8 infusions of 3BNC117 and 10-1074, administered over a period of 24 weeks, were well tolerated without any serious adverse events related to the infusions. Compared with the placebo, the combination broadly neutralizing monoclonal antibodies maintained complete suppression of plasma viraemia (for up to 43 weeks) after analytical treatment interruption, provided that no antibody-resistant HIV was detected at the baseline in the study participants. Similarly, potent HIV suppression was seen in the antiretroviral-therapy-naive study participants with viraemia carrying sensitive virus at the baseline. Our data demonstrate that combination therapy with broadly neutralizing monoclonal antibodies can provide long-term virological suppression without antiretroviral therapy in individuals with HIV, and our experience offers guidance for future clinical trials involving next-generation antibodies with long half-lives.


Assuntos
Fármacos Anti-HIV , Anticorpos Neutralizantes , Anticorpos Anti-HIV , Infecções por HIV , HIV-1 , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/imunologia , Fármacos Anti-HIV/uso terapêutico , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/efeitos adversos , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Amplamente Neutralizantes/administração & dosagem , Anticorpos Amplamente Neutralizantes/efeitos adversos , Anticorpos Amplamente Neutralizantes/imunologia , Anticorpos Amplamente Neutralizantes/uso terapêutico , Método Duplo-Cego , Anticorpos Anti-HIV/administração & dosagem , Anticorpos Anti-HIV/efeitos adversos , Anticorpos Anti-HIV/imunologia , Anticorpos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/imunologia , HIV-1/isolamento & purificação , Humanos , Carga Viral/efeitos dos fármacos , Viremia/tratamento farmacológico , Viremia/imunologia , Viremia/virologia
16.
Proc Natl Acad Sci U S A ; 119(25): e2202059119, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35714289

RESUMO

The bacterial genus Bartonella comprises numerous emerging pathogens that cause a broad spectrum of disease manifestations in humans. The targets and mechanisms of the anti-Bartonella immune defense are ill-defined and bacterial immune evasion strategies remain elusive. We found that experimentally infected mice resolved Bartonella infection by mounting antibody responses that neutralized the bacteria, preventing their attachment to erythrocytes and suppressing bacteremia independent of complement or Fc receptors. Bartonella-neutralizing antibody responses were rapidly induced and depended on CD40 signaling but not on affinity maturation. We cloned neutralizing monoclonal antibodies (mAbs) and by mass spectrometry identified the bacterial autotransporter CFA (CAMP-like factor autotransporter) as a neutralizing antibody target. Vaccination against CFA suppressed Bartonella bacteremia, validating CFA as a protective antigen. We mapped Bartonella-neutralizing mAb binding to a domain in CFA that we found is hypervariable in both human and mouse pathogenic strains, indicating mutational antibody evasion at the Bartonella subspecies level. These insights into Bartonella immunity and immune evasion provide a conceptual framework for vaccine development, identifying important challenges in this endeavor.


Assuntos
Anticorpos Neutralizantes , Antígenos de Bactérias , Bacteriemia , Infecções por Bartonella , Bartonella , Sistemas de Secreção Tipo V , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/imunologia , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Bacteriemia/imunologia , Bacteriemia/microbiologia , Bacteriemia/prevenção & controle , Vacinas Bacterianas/genética , Vacinas Bacterianas/imunologia , Vacinas Bacterianas/uso terapêutico , Bartonella/genética , Bartonella/imunologia , Infecções por Bartonella/imunologia , Infecções por Bartonella/microbiologia , Infecções por Bartonella/prevenção & controle , Clonagem Molecular , Evasão da Resposta Imune , Camundongos , Sistemas de Secreção Tipo V/imunologia , Vacinação
17.
J Biol Rhythms ; 37(5): 562-566, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35730571

RESUMO

To examine whether immunization time affects the immune responses elicited by the BNT162b2 COVID-19 vaccine, we investigated the possible association between total SARS-CoV-2 spike protein receptor binding domain (TAbs-RBD) and neutralizing (NAbs-RBD) antibodies with vaccination time. A cohort of 468 healthcare workers (mean age [±SD]: 48 [±13] years), were included in the study. One month after the second dose, healthcare workers who were vaccinated between 1500-2200 h had higher TAbs-RBD compared to 0700-1100 h and 1100-1500 h (p = 0.006). One month after the third dose, healthcare workers who were vaccinated between 0700-1100 h and 1500-2200 h had significantly higher TAbs-RBD compared to 1100-1500 h (p = 0.034). However, no association of NAbs-RBD with vaccination time was detected after each of the 3 doses (p > 0.4). Despite the possible effect of BNT162b2 vaccination time in TAbs-RBD levels, possibly due to rhythmic expression of clock genes, neutralizing activity was not associated with vaccination time and, therefore, further investigation is required.


Assuntos
Anticorpos Antivirais , Vacina BNT162 , COVID-19 , Ritmo Circadiano , Adulto , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Vacina BNT162/imunologia , COVID-19/prevenção & controle , Humanos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Vacinação
18.
Nature ; 608(7923): 593-602, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35714668

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron sublineages BA.2.12.1, BA.4 and BA.5 exhibit higher transmissibility than the BA.2 lineage1. The receptor binding and immune-evasion capability of these recently emerged variants require immediate investigation. Here, coupled with structural comparisons of the spike proteins, we show that BA.2.12.1, BA.4 and BA.5 (BA.4 and BA.5 are hereafter referred collectively to as BA.4/BA.5) exhibit similar binding affinities to BA.2 for the angiotensin-converting enzyme 2 (ACE2) receptor. Of note, BA.2.12.1 and BA.4/BA.5 display increased evasion of neutralizing antibodies compared with BA.2 against plasma from triple-vaccinated individuals or from individuals who developed a BA.1 infection after vaccination. To delineate the underlying antibody-evasion mechanism, we determined the escape mutation profiles2, epitope distribution3 and Omicron-neutralization efficiency of 1,640 neutralizing antibodies directed against the receptor-binding domain of the viral spike protein, including 614 antibodies isolated from people who had recovered from BA.1 infection. BA.1 infection after vaccination predominantly recalls humoral immune memory directed against ancestral (hereafter referred to as wild-type (WT)) SARS-CoV-2 spike protein. The resulting elicited antibodies could neutralize both WT SARS-CoV-2 and BA.1 and are enriched on epitopes on spike that do not bind ACE2. However, most of these cross-reactive neutralizing antibodies are evaded by spike mutants L452Q, L452R and F486V. BA.1 infection can also induce new clones of BA.1-specific antibodies that potently neutralize BA.1. Nevertheless, these neutralizing antibodies are largely evaded by BA.2 and BA.4/BA.5 owing to D405N and F486V mutations, and react weakly to pre-Omicron variants, exhibiting narrow neutralization breadths. The therapeutic neutralizing antibodies bebtelovimab4 and cilgavimab5 can effectively neutralize BA.2.12.1 and BA.4/BA.5, whereas the S371F, D405N and R408S mutations undermine most broadly sarbecovirus-neutralizing antibodies. Together, our results indicate that Omicron may evolve mutations to evade the humoral immunity elicited by BA.1 infection, suggesting that BA.1-derived vaccine boosters may not achieve broad-spectrum protection against new Omicron variants.


Assuntos
Anticorpos Antivirais , Deriva e Deslocamento Antigênicos , COVID-19 , Epitopos de Linfócito B , Tolerância Imunológica , Mutação , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Deriva e Deslocamento Antigênicos/genética , Deriva e Deslocamento Antigênicos/imunologia , COVID-19/imunologia , COVID-19/transmissão , COVID-19/virologia , Vacinas contra COVID-19/imunologia , Epitopos de Linfócito B/química , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Humanos , Imunidade Humoral , Imunização Secundária , Testes de Neutralização , SARS-CoV-2/classificação , SARS-CoV-2/genética , SARS-CoV-2/imunologia , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo
19.
Proc Natl Acad Sci U S A ; 119(29): e2205784119, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35767670

RESUMO

Many neutralizing antibodies (nAbs) elicited to ancestral severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) through natural infection and vaccination have reduced effectiveness to SARS-CoV-2 variants. Here, we show that therapeutic antibody ADG20 is able to neutralize SARS-CoV-2 variants of concern (VOCs) including Omicron (B.1.1.529) as well as other SARS-related coronaviruses. We delineate the structural basis of this relatively escape-resistant epitope that extends from one end of the receptor binding site (RBS) into the highly conserved CR3022 site. ADG20 can then benefit from high potency through direct competition with ACE2 in the more variable RBS and interaction with the more highly conserved CR3022 site. Importantly, antibodies that are able to target this site generally neutralize a broad range of VOCs, albeit with reduced potency against Omicron. Thus, this conserved and vulnerable site can be exploited for the design of universal vaccines and therapeutic antibodies.


Assuntos
Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/virologia , Epitopos/imunologia , Humanos , Testes de Neutralização , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
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