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1.
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
2.
Front Immunol ; 13: 908108, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35911701

RESUMO

Cancer patients (CPs) have been identified as particularly vulnerable to SARS-CoV-2 infection, and therefore are a priority group for receiving COVID-19 vaccination. From the patients with advanced solid tumors, about 20% respond very efficiently to immunotherapy with anti-PD1/PD-L1 antibodies and achieve long lasting cancer responses. It is unclear whether an efficient cancer-specific immune response may also correlate with an efficient response upon COVID-19 vaccination. Here, we explored the antiviral immune response to the mRNA-based COVID-19 vaccine BNT162b2 in a group of 11 long-lasting cancer immunotherapy responders. We analysed the development of SARS-CoV-2-specific IgG serum antibodies, virus neutralizing capacities and T cell responses. Control groups included patients treated with adjuvant cancer immunotherapy (IMT, cohort B), CPs not treated with immunotherapy (no-IMT, cohort C) and healthy controls (cohort A). The median ELISA IgG titers significantly increased after the prime-boost COVID vaccine regimen in all cohorts (Cohort A: pre-vaccine = 900 (100-2700), 3 weeks (w) post-boost = 24300 (2700-72900); Cohort B: pre-vaccine = 300 (100-2700), 3 w post-boost = 8100 (300-72900); Cohort C: pre-vaccine = 500 (100-2700), 3 w post-boost = 24300 (300-72900)). However, at the 3 w post-prime time-point, only the healthy control group showed a statistically significant increase in antibody levels (Cohort A = 8100 (900-8100); Cohort B = 900 (300-8100); Cohort C = 900 (300-8100)) (P < 0.05). Strikingly, while all healthy controls generated high-level antibody responses after the complete prime-boost regimen (Cohort A = 15/15 (100%), not all CPs behaved alike [Cohort B= 12/14 (84'6%); Cohort C= 5/6 (83%)]. Their responses, including those of the long-lasting immunotherapy responders, were more variable (Cohort A: 3 w post-boost (median nAb titers = 95.32 (84.09-96.93), median Spike-specific IFN-γ response = 64 (24-150); Cohort B: 3 w post-boost (median nAb titers = 85.62 (8.22-97.19), median Spike-specific IFN-γ response (28 (1-372); Cohort C: 3 w post-boost (median nAb titers = 95.87 (11.8-97.3), median Spike-specific IFN-γ response = 67 (20-84)). Two long-lasting cancer responders did not respond properly to the prime-boost vaccination and did not generate S-specific IgGs, neutralizing antibodies or virus-specific T cells, although their cancer immune control persisted for years. Thus, although mRNA-based vaccines can induce both antibody and T cell responses in CPs, the immune response to COVID vaccination is independent of the capacity to develop an efficient anti-cancer immune response to anti PD-1/PD-L1 antibodies.


Assuntos
Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Vacinas Virais , Antígeno B7-H1 , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Humanos , Imunoglobulina G , Imunoterapia , Neoplasias/terapia , Relatório de Pesquisa , SARS-CoV-2/imunologia , Vacinação , Vacinas de mRNA/imunologia
3.
J Biomed Sci ; 29(1): 52, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35820906

RESUMO

BACKGROUND: Coronavirus-induced disease 19 (COVID-19) infects more than three hundred and sixty million patients worldwide, and people with severe symptoms frequently die of acute respiratory distress syndrome (ARDS). Recent studies indicated that excessive neutrophil extracellular traps (NETs) contributed to immunothrombosis, thereby leading to extensive intravascular coagulopathy and multiple organ dysfunction. Thus, understanding the mechanism of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced NET formation would be helpful to reduce thrombosis and prevent ARDS in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. METHODS: We incubated SARS-CoV-2 with neutrophils in the presence or absence of platelets to observe NET formation. We further isolated extracellular vesicles from COVID-19 patients' sera (COVID-19-EVs) to examine their ability to induce NET formation. RESULTS: We demonstrated that antagonistic mAbs against anti-CLEC5A mAb and anti-TLR2 mAb can inhibit COVID-19-EVs-induced NET formation, and generated clec5a-/-/tlr2-/- mice to confirm the critical roles of CLEC5A and TLR2 in SARS-CoV-2-induced lung inflammation in vivo. We found that virus-free extracellular COVID-19 EVs induced robust NET formation via Syk-coupled C-type lectin member 5A (CLEC5A) and TLR2. Blockade of CLEC5A inhibited COVID-19 EVs-induced NETosis, and simultaneous blockade of CLEC5A and TLR2 further suppressed SARS-CoV-2-induced NETosis in vitro. Moreover, thromboinflammation was attenuated dramatically in clec5a-/-/tlr2-/- mice. CONCLUSIONS: This study demonstrates that SARS-CoV-2-activated platelets produce EVs to enhance thromboinflammation via CLEC5A and TLR2, and highlight the importance of CLEC5A and TLR2 as therapeutic targets to reduce the risk of ARDS in COVID-19 patients.


Assuntos
COVID-19 , Lectinas Tipo C , Neutrófilos , Pneumonia , Síndrome do Desconforto Respiratório , SARS-CoV-2 , Trombose , Animais , Plaquetas/imunologia , Plaquetas/patologia , Plaquetas/virologia , COVID-19/sangue , COVID-19/imunologia , Humanos , Lectinas Tipo C/imunologia , Camundongos , Neutrófilos/imunologia , Neutrófilos/patologia , Neutrófilos/virologia , Pneumonia/imunologia , Pneumonia/patologia , Pneumonia/virologia , Receptores de Superfície Celular , Síndrome do Desconforto Respiratório/imunologia , Síndrome do Desconforto Respiratório/virologia , SARS-CoV-2/imunologia , Trombose/sangue , Trombose/imunologia , Trombose/virologia , Receptor 2 Toll-Like/imunologia
4.
Methods Mol Biol ; 2511: 21-36, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35838949

RESUMO

The emergence of new SARS-CoV-2 variants has led to increased transmission and more severe cases of COVID-19, with some having the ability to escape the existing vaccines. This review discusses the importance of developing new vaccine strategies to keep pace with these variants to more effectively manage the pandemic. Many of the new vaccine approaches include multivalent display of the most highly mutated regions in the SARS-CoV-2 spike protein such that they resemble a virus particle and can stimulate an effective neutralization response. It is hoped that such approaches help to manage the existing pandemic and provide a robust infrastructure toward fast tracking responses across the world in case of future pandemics.


Assuntos
Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Vacinas Combinadas , COVID-19/prevenção & controle , Humanos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética
5.
Proc Natl Acad Sci U S A ; 119(30): e2203659119, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35858456

RESUMO

This study analyzed whole blood samples (n = 56) retrieved from 30 patients at 1 to 21 (median 9) mo after verified COVID-19 to determine the polarity and duration of antigen-specific T cell reactivity against severe acute respiratory syndrome coronavirus 2-derived antigens. Multimeric peptides spanning the entire nucleocapsid protein triggered strikingly synchronous formation of interleukin (IL)-4, IL-12, IL-13, and IL-17 ex vivo until ∼70 d after confirmed infection, whereafter this reactivity was no longer inducible. In contrast, levels of nucleocapsid-induced IL-2 and interferon-γ remained stable and highly correlated at 3 to 21 mo after infection. Similar cytokine dynamics were observed in unvaccinated, convalescent patients using whole-blood samples stimulated with peptides spanning the N-terminal portion of the spike 1 protein. These results unravel two phases of T cell reactivity following natural COVID-19: an early, synchronous response indicating transient presence of multipolar, antigen-specific T helper (TH) cells followed by an equally synchronous and durable TH1-like reactivity reflecting long-lasting T cell memory.


Assuntos
COVID-19 , Citocinas , SARS-CoV-2 , Linfócitos T Auxiliares-Indutores , Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , COVID-19/sangue , COVID-19/imunologia , Convalescença , Citocinas/sangue , Humanos , Interferon gama/sangue , Proteínas do Nucleocapsídeo/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T Auxiliares-Indutores/imunologia
6.
Int J Mol Sci ; 23(13)2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35805975

RESUMO

The SARS-CoV-2 disease presents different phenotypes of severity. Comorbidities, age, and being overweight are well established risk factors for severe disease. However, innate immunity plays a key role in the early control of viral infections and may condition the gravity of COVID-19. Natural Killer (NK) cells are part of innate immunity and are important in the control of virus infection by killing infected cells and participating in the development of adaptive immunity. Therefore, we studied the short tandem repeat (STR) transmembrane polymorphisms of the major histocompatibility complex class I chain-related A (MICA), an NKG2D ligand that induces activation of NK cells, among other cells. We compared the alleles and genotypes of MICA in COVID-19 patients versus healthy controls and analyzed their relation to disease severity. Our results indicate that the MICA*A9 allele is related to infection as well as to symptomatic disease but not to severe disease. The MICA*A9 allele may be a risk factor for SARS-CoV-2 infection and symptomatic disease.


Assuntos
COVID-19 , Antígenos de Histocompatibilidade Classe I , COVID-19/genética , COVID-19/imunologia , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Complexo Principal de Histocompatibilidade , Polimorfismo Genético , SARS-CoV-2/imunologia
8.
Proc Natl Acad Sci U S A ; 119(31): e2204336119, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35858382

RESUMO

The durability of vaccine-mediated immunity to SARS-CoV-2, the durations to breakthrough infection, and the optimal timings of booster vaccination are crucial knowledge for pandemic response. Here, we applied comparative evolutionary analyses to estimate the durability of immunity and the likelihood of breakthrough infections over time following vaccination by BNT162b2 (Pfizer-BioNTech), mRNA-1273 (Moderna), ChAdOx1 (Oxford-AstraZeneca), and Ad26.COV2.S (Johnson & Johnson/Janssen). We evaluated anti-Spike (S) immunoglobulin G (IgG) antibody levels elicited by each vaccine relative to natural infection. We estimated typical trajectories of waning and corresponding infection probabilities, providing the distribution of times to breakthrough infection for each vaccine under endemic conditions. Peak antibody levels elicited by messenger RNA (mRNA) vaccines mRNA-1273 and BNT1262b2 exceeded that of natural infection and are expected to typically yield more durable protection against breakthrough infections (median 29.6 mo; 5 to 95% quantiles 10.9 mo to 7.9 y) than natural infection (median 21.5 mo; 5 to 95% quantiles 3.5 mo to 7.1 y). Relative to mRNA-1273 and BNT1262b2, viral vector vaccines ChAdOx1 and Ad26.COV2.S exhibit similar peak anti-S IgG antibody responses to that from natural infection and are projected to yield lower, shorter-term protection against breakthrough infection (median 22.4 mo and 5 to 95% quantiles 4.3 mo to 7.2 y; and median 20.5 mo and 5 to 95% quantiles 2.6 mo to 7.0 y; respectively). These results leverage the tools from evolutionary biology to provide a quantitative basis for otherwise unknown parameters that are fundamental to public health policy decision-making.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Imunogenicidade da Vacina , SARS-CoV-2 , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Formação de Anticorpos , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/uso terapêutico , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Fatores de Tempo
9.
Proc Natl Acad Sci U S A ; 119(31): e2205412119, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35858383

RESUMO

Camelid single-domain antibodies, also known as nanobodies, can be readily isolated from naïve libraries for specific targets but often bind too weakly to their targets to be immediately useful. Laboratory-based genetic engineering methods to enhance their affinity, termed maturation, can deliver useful reagents for different areas of biology and potentially medicine. Using the receptor binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein and a naïve library, we generated closely related nanobodies with micromolar to nanomolar binding affinities. By analyzing the structure-activity relationship using X-ray crystallography, cryoelectron microscopy, and biophysical methods, we observed that higher conformational entropy losses in the formation of the spike protein-nanobody complex are associated with tighter binding. To investigate this, we generated structural ensembles of the different complexes from electron microscopy maps and correlated the conformational fluctuations with binding affinity. This insight guided the engineering of a nanobody with improved affinity for the spike protein.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Afinidade de Anticorpos , SARS-CoV-2 , Anticorpos de Domínio Único , Glicoproteína da Espícula de Coronavírus , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/genética , Anticorpos Antivirais/química , Anticorpos Antivirais/genética , Afinidade de Anticorpos/genética , Microscopia Crioeletrônica , Entropia , Engenharia Genética , Humanos , Ligação Proteica , Domínios Proteicos , SARS-CoV-2/imunologia , Anticorpos de Domínio Único/química , Anticorpos de Domínio Único/genética , Glicoproteína da Espícula de Coronavírus/imunologia
10.
Proc Natl Acad Sci U S A ; 119(32): e2203760119, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35867811

RESUMO

The emergence of SARS-CoV-2 variants with enhanced transmissibility, pathogenesis, and resistance to vaccines presents urgent challenges for curbing the COVID-19 pandemic. While Spike mutations that enhance virus infectivity or neutralizing antibody evasion may drive the emergence of these novel variants, studies documenting a critical role for interferon responses in the early control of SARS-CoV-2 infection, combined with the presence of viral genes that limit these responses, suggest that interferons may also influence SARS-CoV-2 evolution. Here, we compared the potency of 17 different human interferons against multiple viral lineages sampled during the course of the global outbreak, including ancestral and five major variants of concern that include the B.1.1.7 (alpha), B.1.351 (beta), P.1 (gamma), B.1.617.2 (delta), and B.1.1.529 (omicron) lineages. Our data reveal that relative to ancestral isolates, SARS-CoV-2 variants of concern exhibited increased interferon resistance, suggesting that evasion of innate immunity may be a significant, ongoing driving force for SARS-CoV-2 evolution. These findings have implications for the increased transmissibility and/or lethality of emerging variants and highlight the interferon subtypes that may be most successful in the treatment of early infections.


Assuntos
Antivirais , COVID-19 , Interferons , SARS-CoV-2 , Anticorpos Neutralizantes , Antivirais/farmacologia , Antivirais/uso terapêutico , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/transmissão , Humanos , Interferons/farmacologia , Interferons/uso terapêutico , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética
11.
Proc Natl Acad Sci U S A ; 119(33): e2201616119, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35895717

RESUMO

With the rapid increase in SARS-CoV-2 cases in children, a safe and effective vaccine for this population is urgently needed. The MMR (measles/mumps/rubella) vaccine has been one of the safest and most effective human vaccines used in infants and children since the 1960s. Here, we developed live attenuated recombinant mumps virus (rMuV)-based SARS-CoV-2 vaccine candidates using the MuV Jeryl Lynn (JL2) vaccine strain backbone. The soluble prefusion SARS-CoV-2 spike protein (preS) gene, stablized by two prolines (preS-2P) or six prolines (preS-6P), was inserted into the MuV genome at the P-M or F-SH gene junctions in the MuV genome. preS-6P was more efficiently expressed than preS-2P, and preS-6P expression from the P-M gene junction was more efficient than from the F-SH gene junction. In mice, the rMuV-preS-6P vaccine was more immunogenic than the rMuV-preS-2P vaccine, eliciting stronger neutralizing antibodies and mucosal immunity. Sera raised in response to the rMuV-preS-6P vaccine neutralized SARS-CoV-2 variants of concern, including the Delta variant equivalently. Intranasal and/or subcutaneous immunization of IFNAR1-/- mice and golden Syrian hamsters with the rMuV-preS-6P vaccine induced high levels of neutralizing antibodies, mucosal immunoglobulin A antibody, and T cell immune responses, and were completely protected from challenge by both SARS-CoV-2 USA-WA1/2020 and Delta variants. Therefore, rMuV-preS-6P is a highly promising COVID-19 vaccine candidate, warranting further development as a tetravalent MMR vaccine, which may include protection against SARS-CoV-2.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Vacina contra Sarampo-Caxumba-Rubéola , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Eficácia de Vacinas , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/prevenção & controle , Vacinas contra COVID-19/genética , Vacinas contra COVID-19/imunologia , Imunogenicidade da Vacina , Vacina contra Sarampo-Caxumba-Rubéola/genética , Vacina contra Sarampo-Caxumba-Rubéola/imunologia , Mesocricetus , Camundongos , Vírus da Caxumba/genética , Vírus da Caxumba/imunologia , Prolina/genética , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia
12.
PLoS One ; 17(7): e0271463, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35834480

RESUMO

γδ T cells are thought to contribute to immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but the mechanisms by which they are activated by the virus are unknown. Using flow cytometry, we investigated if the two most abundant viral structural proteins, spike and nucleocapsid, can activate human γδ T cell subsets, directly or in the presence of dendritic cells (DC). Both proteins failed to induce interferon-γ production by Vδ1 or Vδ2 T cells within fresh mononuclear cells or lines of expanded γδ T cells generated from healthy donors, but the same proteins stimulated CD3+ cells from COVID-19 patients. The nucleocapsid protein stimulated interleukin-12 production by DC and downstream interferon-γ production by co-cultured Vδ1 and Vδ2 T cells, but protease digestion and use of an alternative nucleocapsid preparation indicated that this activity was due to contaminating non-protein material. Thus, SARS-CoV-2 spike and nucleocapsid proteins do not have stimulatory activity for DC or γδ T cells. We propose that γδ T cell activation in COVID-19 patients is mediated by immune recognition of viral RNA or other structural proteins by γδ T cells, or by other immune cells, such as DC, that produce γδ T cell-stimulatory ligands or cytokines.


Assuntos
COVID-19 , Células Dendríticas , Proteínas do Nucleocapsídeo , Receptores de Antígenos de Linfócitos T gama-delta , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , COVID-19/imunologia , COVID-19/virologia , Células Dendríticas/imunologia , Humanos , Interferon gama/imunologia , Proteínas do Nucleocapsídeo/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
15.
Proc Natl Acad Sci U S A ; 119(29): e2205784119, 2022 Jul 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
16.
Science ; 377(6603): eabq1841, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35699621

RESUMO

The Omicron, or Pango lineage B.1.1.529, variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) carries multiple spike mutations with high transmissibility and partial neutralizing antibody (nAb) escape. Vaccinated individuals show protection against severe disease, often attributed to primed cellular immunity. We investigated T and B cell immunity against B.1.1.529 in triple BioNTech BNT162b2 messenger RNA-vaccinated health care workers (HCWs) with different SARS-CoV-2 infection histories. B and T cell immunity against previous variants of concern was enhanced in triple-vaccinated individuals, but the magnitude of T and B cell responses against B.1.1.529 spike protein was reduced. Immune imprinting by infection with the earlier B.1.1.7 (Alpha) variant resulted in less durable binding antibody against B.1.1.529. Previously infection-naïve HCWs who became infected during the B.1.1.529 wave showed enhanced immunity against earlier variants but reduced nAb potency and T cell responses against B.1.1.529 itself. Previous Wuhan Hu-1 infection abrogated T cell recognition and any enhanced cross-reactive neutralizing immunity on infection with B.1.1.529.


Assuntos
Linfócitos B , Vacina BNT162 , COVID-19 , Imunização Secundária , SARS-CoV-2 , Linfócitos T , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Linfócitos B/imunologia , Vacina BNT162/imunologia , Vacina BNT162/uso terapêutico , COVID-19/imunologia , COVID-19/prevenção & controle , Reações Cruzadas , Humanos , Camundongos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T/imunologia
17.
Front Immunol ; 13: 918881, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35757773

RESUMO

Angiotensin Converting Enzyme 2 (ACE2) is the primary cell entry receptor for SARS-CoV and SARS-CoV-2 viruses. A disintegrin and metalloproteinase 17 (ADAM17) is a protease that cleaves ectodomains of transmembrane proteins, including that of ACE2 and the proinflammatory cytokine TNF-α, from cell surfaces upon cellular activation. We hypothesized that blockade of ADAM17 activity would alter COVID-19 pathogenesis. To assess this pathway, we blocked the function of ADAM17 using the monoclonal antibody MEDI3622 in the K18-hACE2 transgenic mouse model of COVID-19. Antibody-treated mice were healthier, less moribund, and had significantly lower lung pathology than saline-treated mice. However, the viral burden in the lungs of MEDI3622-treated mice was significantly increased. Thus, ADAM17 appears to have a critical anti-viral role, but also may promote inflammatory damage. Since the inflammatory cascade is ultimately the reason for adverse outcomes in COVID-19 patients, there may be a therapeutic application for the MEDI3622 antibody.


Assuntos
Proteína ADAM17 , Anticorpos Neutralizantes , COVID-19 , SARS-CoV-2 , Proteína ADAM17/antagonistas & inibidores , Proteína ADAM17/imunologia , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/farmacologia , COVID-19/imunologia , COVID-19/terapia , COVID-19/virologia , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Transgênicos , Peptidil Dipeptidase A/metabolismo , SARS-CoV-2/imunologia , Carga Viral
18.
Proc Natl Acad Sci U S A ; 119(24): e2202069119, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35679343

RESUMO

Current vaccines have greatly diminished the severity of the COVID-19 pandemic, even though they do not entirely prevent infection and transmission, likely due to insufficient immunity in the upper respiratory tract. Here, we compare intramuscular and intranasal administration of a live, replication-deficient modified vaccinia virus Ankara (MVA)-based Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) spike (S) vaccine to raise protective immune responses in the K18-hACE2 mouse model. Using a recombinant MVA expressing firefly luciferase for tracking, live imaging revealed luminescence of the respiratory tract of mice within 6 h and persisting for 3 d following intranasal inoculation, whereas luminescence remained at the site of intramuscular vaccination. Intramuscular vaccination induced S-binding-Immunoglobulin G (IgG) and neutralizing antibodies in the lungs, whereas intranasal vaccination also induced Immunoglobulin A (IgA) and higher levels of antigen-specific CD3+CD8+IFN-γ+ T cells. Similarly, IgG and neutralizing antibodies were present in the blood of mice immunized intranasally and intramuscularly, but IgA was detected only after intranasal inoculation. Intranasal boosting increased IgA after intranasal or intramuscular priming. While intramuscular vaccination prevented morbidity and cleared SARS-CoV-2 from the respiratory tract within several days after challenge, intranasal vaccination was more effective as neither infectious virus nor viral messenger (m)RNAs were detected in the nasal turbinates or lungs as early as 2 d after challenge, indicating prevention or rapid elimination of SARS-CoV-2 infection. Additionally, we determined that neutralizing antibody persisted for more than 6 mo and that serum induced to the Wuhan S protein neutralized pseudoviruses expressing the S proteins of variants, although with less potency, particularly for Beta and Omicron.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Imunoglobulina A , Sistema Respiratório , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Vírus Vaccinia , Administração Intranasal , Enzima de Conversão de Angiotensina 2/genética , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/prevenção & controle , COVID-19/transmissão , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Camundongos , Camundongos Transgênicos , Sistema Respiratório/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação/métodos , Vírus Vaccinia/genética , Vírus Vaccinia/imunologia
19.
J Virol ; 96(13): e0038322, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35699445

RESUMO

Despite the rapid deployment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines, the emergence of SARS-CoV-2 variants and reports of their immune evasion characteristics have led to an urgent need for novel vaccines that confer potent cross-protective immunity. In this study, we constructed three different SARS-CoV-2 spike S1-conjugated nanoparticle vaccine candidates that exhibited high structural homogeneity and stability. Notably, these vaccines elicited up to 50-times-higher neutralizing antibody titers than the S1 monomer in mice. Crucially, it was found that the S1-conjugated nanoparticle vaccine could elicit comparable levels of neutralizing antibodies against wild-type or emerging variant SARS-CoV-2, with cross-reactivity to SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV), the effect of which could be further enhanced using our designed nanoparticles. Our results indicate that the S1-conjugated nanoparticles are promising vaccine candidates with the potential to elicit potent and cross-reactive immunity against not only wild-type SARS-CoV-2, but also its variants of concern, variants of interest, and even other pathogenic betacoronaviruses. IMPORTANCE The emergence of SARS-CoV-2 variants led to an urgent demand for a broadly effective vaccine against the threat of variant infection. The spike protein S1-based nanoparticle designed in our study could elicit a comprehensive humoral response toward different SARS-CoV-2 variants of concern and variants of interest and will be helpful to combat COVID-19 globally.


Assuntos
Formação de Anticorpos , Vacinas contra COVID-19 , COVID-19 , Nanopartículas , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Formação de Anticorpos/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Humanos , Camundongos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
20.
Proc Natl Acad Sci U S A ; 119(28): e2202370119, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35749382

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections initiate in the bronchi of the upper respiratory tract and are able to disseminate to the lower respiratory tract, where infections can cause an acute respiratory distress syndrome with a high degree of mortality in elderly patients. We used reconstituted primary bronchial epithelia from adult and child donors to follow the SARS-CoV-2 infection dynamics. We show that, in epithelia from adult donors, infections initiate in multiciliated cells and spread within 24 to 48 h throughout the whole epithelia. Syncytia formed of ciliated and basal cells appeared at the apical side of the epithelia within 3 to 4 d and were released into the apical lumen, where they contributed to the transmittable virus dose. A small number of reconstituted epithelia were intrinsically more resistant to virus infection, limiting virus spread to different degrees. This phenotype was more frequent in epithelia derived from children versus adults and correlated with an accelerated release of type III interferon. Treatment of permissive adult epithelia with exogenous type III interferon restricted infection, while type III interferon gene knockout promoted infection. Furthermore, a transcript analysis revealed that the inflammatory response was specifically attenuated in children. Taken together, our findings suggest that apical syncytia formation is an underappreciated source of virus propagation for tissue or environmental dissemination, whereas a robust type III interferon response such as commonly seen in young donors restricted SARS-CoV-2 infection. Thus, the combination of interferon restriction and attenuated inflammatory response in children might explain the epidemiological observation of age-related susceptibility to COVID-19.


Assuntos
Brônquios , COVID-19 , Células Gigantes , Interferons , Mucosa Respiratória , SARS-CoV-2 , Idoso , Brônquios/imunologia , Brônquios/virologia , COVID-19/imunologia , COVID-19/virologia , Criança , Suscetibilidade a Doenças , Células Gigantes/imunologia , Células Gigantes/virologia , Humanos , Interferons/imunologia , Mucosa Respiratória/imunologia , Mucosa Respiratória/virologia , SARS-CoV-2/imunologia
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