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1.
Sci Rep ; 13(1): 306, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609657

RESUMO

Monoclonal antibodies (mAbs) play an important role in diagnostics and therapy of infectious diseases. Here we utilize a single-particle interferometric reflectance imaging sensor (SP-IRIS) for screening 30 mAbs against Ebola, Sudan, and Lassa viruses (EBOV, SUDV, and LASV) to find out the ideal capture antibodies for whole virus detection using recombinant vesicular stomatitis virus (rVSV) models expressing surface glycoproteins (GPs) of EBOV, SUDV, and LASV. We also make use of the binding properties on SP-IRIS to develop a model for mapping the antibody epitopes on the GP structure. mAbs that bind to mucin-like domain or glycan cap of the EBOV surface GP show the highest signal on SP-IRIS, followed by mAbs that target the GP1-GP2 interface at the base domain. These antibodies were shown to be highly efficacious against EBOV infection in non-human primates in previous studies. For LASV detection, 8.9F antibody showed the best performance on SP-IRIS. This antibody binds to a unique region on the surface GP compared to other 15 mAbs tested. In addition, we demonstrate a novel antibody competition assay using SP-IRIS and rVSV-EBOV models to reveal the competition between mAbs in three successful therapeutic mAb cocktails against EBOV infection. We provide an explanation as to why ZMapp cocktail has higher efficacy compared to the other two cocktails by showing that three mAbs in this cocktail (13C6, 2G4, 4G7) do not compete with each other for binding to EBOV GP. In fact, the binding of 13C6 enhances the binding of 2G4 and 4G7 antibodies. Our results establish SP-IRIS as a versatile tool that can provide high-throughput screening of mAbs, multiplexed and sensitive detection of viruses, and evaluation of therapeutic antibody cocktails.


Assuntos
Ebolavirus , Doença pelo Vírus Ebola , Animais , Anticorpos Antivirais , Fatores Imunológicos/metabolismo , Epitopos , Anticorpos Neutralizantes
2.
Arch Virol ; 168(2): 49, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36609880

RESUMO

Bovine viral diarrhea virus (BVDV) is a pathogen of commercial consequence in cattle. Although many modified live and killed vaccines are commercially available, their drawbacks precipitate the need for new effective vaccines. Virus-like particles (VLPs) are a safe and powerful technology used in several human and veterinary vaccines; however, it is difficult to produce large amounts of BVDV VLPs. In this study, we generated red-spotted grouper nervous necrosis virus (RGNNV) VLPs presenting the BVDV E2 protein (domain I to IIIb) of the Nose (BVDV-1) or KZ-91-CP (BVDV-2) strain by exploiting SpyTag/SpyCatcher technology. Mice immunized twice with 30 µg of RGNNV VLPs conjugated with 10 µg of E2 proteins of the Nose or KZ-91-CP strain with a 14-day interval elicited high (1:512,000 to 1:1,024,000) and moderate (1:25,600 to 1:102,400) IgG titers against E2 proteins of homologous and heterologous strains, respectively. In addition, this prime-boost regimen induced strong (1:800 to 1:3,200) and weak (~1:10) neutralization titers against homologous and heterologous BVDV strains, respectively. Our results indicate that conjugation of the E2 protein to RGNNV VLPs strongly enhances the antigenicity of the E2 protein and that RGNNV VLPs presenting the E2 protein are promising BVDV vaccine candidates.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina , Vírus da Diarreia Viral Bovina Tipo 1 , Vírus da Diarreia Viral Bovina , Vacinas de Partículas Semelhantes a Vírus , Vacinas Virais , Humanos , Bovinos , Animais , Camundongos , Anticorpos Neutralizantes , Anticorpos Antivirais , Proteínas do Envelope Viral/genética , Diarreia
3.
Viral Immunol ; 36(1): 63-70, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36648773

RESUMO

Understanding the functional characteristics of antibodies produced against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) will assist in the determination of disease outcomes for this virus. In this study, the ability of antibodies to inhibit viral entry into the host cell through the interaction of the receptor binding domain of the viral spike protein and the angiotensin-converting enzyme 2 receptor on the human cell surface was investigated. The SARS-CoV-2 IgG levels in 20 SARS-CoV-2 positive patients were measured using an enzyme-linked immunosorbent assay, and the samples were further analyzed using a functional binding assay. Inhibition of viral infectivity was also measured using a pseudovirus neutralization assay against a D614G SARS-CoV-2 virus strain. A significant correlation between IgG levels and neutralizing antibody 50% inhibitory concentration (IC50) titers was observed (p < 0.05). Similarly, the IC50 titers obtained in the neutralization and binding assays were significantly correlated (p < 0.001). Varying levels of IgG and IC50 titers were observed for the SARS-CoV-2 antibody-positive samples, with one sample not showing any neutralizing capability despite detectable IgG levels. Gender comparisons showed no statistical differences in any of the assays. These results suggest that increased SARS-CoV-2 IgG levels correlate with greater protection against the entry of the virus into cells; however, further investigations in larger studies are needed to confirm the correlates of protection.


Assuntos
COVID-19 , Humanos , Enzima de Conversão de Angiotensina 2 , Anticorpos Neutralizantes , Anticorpos Antivirais , Imunoglobulina G , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química
4.
Nat Commun ; 14(1): 311, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658148

RESUMO

Antibody-mediated immunity plays a crucial role in protection against SARS-CoV-2 infection. We isolated a panel of neutralizing anti-receptor-binding domain (RBD) antibodies elicited upon natural infection and vaccination and showed that they recognize an immunogenic patch on the internal surface of the core RBD, which faces inwards and is hidden in the "down" state. These antibodies broadly neutralize wild type (Wuhan-Hu-1) SARS-CoV-2, Beta and Delta variants and some are effective against other sarbecoviruses. We observed a continuum of partially overlapping antibody epitopes from lower to upper part of the inner face of the RBD and some antibodies extend towards the receptor-binding motif. The majority of antibodies are substantially compromised by three mutational hotspots (S371L/F, S373P and S375F) in the lower part of the Omicron BA.1, BA.2 and BA.4/5 RBD. By contrast, antibody IY-2A induces a partial unfolding of this variable region and interacts with a conserved conformational epitope to tolerate all antigenic variations and neutralize diverse sarbecoviruses as well. This finding establishes that antibody recognition is not limited to the normal surface structures on the RBD. In conclusion, the delineation of functionally and structurally conserved RBD epitopes highlights potential vaccine and therapeutic candidates for COVID-19.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , Glicoproteína da Espícula de Coronavírus , Humanos , Epitopos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia
5.
Cell Host Microbe ; 31(1): 135-136, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36634618

RESUMO

In the December 22 issue of Cell, Bartsch et al. describe functional profiling of the antibody response to respiratory syncytial virus in human adults vaccinated with an experimental adenovirus-based prefusion-stabilized HRSV-F vaccine and subsequently intranasally challenged with HRSV. The authors identified various antibody effector functions as humoral correlates of protection.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Humanos , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Anticorpos Antivirais , Anticorpos Neutralizantes , Proteínas Virais de Fusão
6.
Pediatr Infect Dis J ; 42(2): 125-129, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36638398

RESUMO

BACKGROUND: Although severe COVID-19 in children is rare, those with certain pre-existing health conditions are more prone to severe disease. Monoclonal antibodies (mAbs) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are potent antiviral agents that reduce adverse clinical outcomes in adults, but are commonly not approved for use in pediatric patients. METHODS: We retrospectively evaluated mAb treatment in children <12 years of age or <40kg with SARS-CoV-2 infection between January 1, 2021, and March 7, 2022, in 12 tertiary care centers in 3 European countries. RESULTS: We received data from 53 patients from Austria, Denmark and Germany. Median age was 5.4 years [0-13.8, interquartile range (IQR) = 6.2], and median body weight was 20 kg (3-50.1, IQR = 13). The most frequent SARS-CoV-2 variant in this study, if known, was Omicron, followed by Delta and Alpha. Pre-existing conditions included immunodeficiency, malignancy, hematologic disease, cardiac disease, chronic lung disease, chronic liver disease, kidney disease and diabetes. Forty-two patients received sotrovimab (79%), 9 casirivimab/imdevimab (17%) and 2 bamlanivimab (4%). All but 1 patient survived. Median duration of hospital stay was 3 days (0-56, IQR = 6). Seven patients required treatment in an intensive care unit, and 5 required high-flow nasal cannula treatment. Potential side effects included neutropenia (6/53, 11%), lymphopenia (3/53, 6%), nausea or vomiting (2/53, 4%), rise of alanine transaminase (1/53, 2%) and hypotonia (1/53, 2%). CONCLUSIONS: MAb treatment was well tolerated by children in this cohort.


Assuntos
COVID-19 , Leucopenia , Adulto , Humanos , Criança , Lactente , Pré-Escolar , Estudos Retrospectivos , SARS-CoV-2 , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes , Anticorpos Antivirais , Doença Crônica
7.
Cell Chem Biol ; 30(1): 85-96.e6, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36640761

RESUMO

As a clinical vaccine, lipid nanoparticle (LNP) mRNA has demonstrated potent and broad antibody responses, leading to speculation about its potential for antibody discovery. Here, we developed RAMIHM, a highly efficient strategy for developing fully human monoclonal antibodies that employs rapid mRNA immunization of humanized mice followed by single B cell sequencing (scBCR-seq). We immunized humanized transgenic mice with RAMIHM and generated 15 top-ranked clones from peripheral blood, plasma B, and memory B cell populations, demonstrating a high rate of antigen-specificity (93.3%). Two Omicron-specific neutralizing antibodies with high potency and one broad-spectrum neutralizing antibody were discovered. Furthermore, we extended the application of RAMIHM to cancer immunotherapy targets, including a single transmembrane protein CD22 and a multi-transmembrane G protein-coupled receptor target, GPRC5D, which is difficult for traditional protein immunization methods. RAMIHM-scBCR-seq is a broadly applicable platform for the rapid and efficient development of fully human monoclonal antibodies against an assortment of targets.


Assuntos
Anticorpos Monoclonais , Imunização , Camundongos , Humanos , Animais , Anticorpos Monoclonais/genética , RNA Mensageiro/genética , Vacinação , Anticorpos Neutralizantes/genética , Camundongos Transgênicos
8.
N Engl J Med ; 388(3): 214-227, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36652353

RESUMO

BACKGROUND: The emergence of immune-escape variants of severe acute respiratory syndrome coronavirus 2 warrants the use of sequence-adapted vaccines to provide protection against coronavirus disease 2019. METHODS: In an ongoing phase 3 trial, adults older than 55 years who had previously received three 30-µg doses of the BNT162b2 vaccine were randomly assigned to receive 30 µg or 60 µg of BNT162b2, 30 µg or 60 µg of monovalent B.1.1.529 (omicron) BA.1-adapted BNT162b2 (monovalent BA.1), or 30 µg (15 µg of BNT162b2 + 15 µg of monovalent BA.1) or 60 µg (30 µg of BNT162b2 + 30 µg of monovalent BA.1) of BA.1-adapted BNT162b2 (bivalent BA.1). Primary objectives were to determine superiority (with respect to 50% neutralizing titer [NT50] against BA.1) and noninferiority (with respect to seroresponse) of the BA.1-adapted vaccines to BNT162b2 (30 µg). A secondary objective was to determine noninferiority of bivalent BA.1 to BNT162b2 (30 µg) with respect to neutralizing activity against the ancestral strain. Exploratory analyses assessed immune responses against omicron BA.4, BA.5, and BA.2.75 subvariants. RESULTS: A total of 1846 participants underwent randomization. At 1 month after vaccination, bivalent BA.1 (30 µg and 60 µg) and monovalent BA.1 (60 µg) showed neutralizing activity against BA.1 superior to that of BNT162b2 (30 µg), with NT50 geometric mean ratios (GMRs) of 1.56 (95% confidence interval [CI], 1.17 to 2.08), 1.97 (95% CI, 1.45 to 2.68), and 3.15 (95% CI, 2.38 to 4.16), respectively. Bivalent BA.1 (both doses) and monovalent BA.1 (60 µg) were also noninferior to BNT162b2 (30 µg) with respect to seroresponse against BA.1; between-group differences ranged from 10.9 to 29.1 percentage points. Bivalent BA.1 (either dose) was noninferior to BNT162b2 (30 µg) with respect to neutralizing activity against the ancestral strain, with NT50 GMRs of 0.99 (95% CI, 0.82 to 1.20) and 1.30 (95% CI, 1.07 to 1.58), respectively. BA.4-BA.5 and BA.2.75 neutralizing titers were numerically higher with 30-µg bivalent BA.1 than with 30-µg BNT162b2. The safety profile of either dose of monovalent or bivalent BA.1 was similar to that of BNT162b2 (30 µg). Adverse events were more common in the 30-µg monovalent-BA.1 (8.5%) and 60-µg bivalent-BA.1 (10.4%) groups than in the other groups (3.6 to 6.6%). CONCLUSIONS: The candidate monovalent or bivalent omicron BA.1-adapted vaccines had a safety profile similar to that of BNT162b2 (30 µg), induced substantial neutralizing responses against ancestral and omicron BA.1 strains, and, to a lesser extent, neutralized BA.4, BA.5, and BA.2.75 strains. (Funded by BioNTech and Pfizer; ClinicalTrials.gov number, NCT04955626.).


Assuntos
Vacina BNT162 , COVID-19 , SARS-CoV-2 , Vacinas Combinadas , Humanos , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacina BNT162/efeitos adversos , Vacina BNT162/imunologia , Vacina BNT162/uso terapêutico , COVID-19/genética , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Vacinação , Vacinas Combinadas/uso terapêutico , Pessoa de Meia-Idade
9.
Nat Commun ; 14(1): 331, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658109

RESUMO

In the PREVENT-19 phase 3 trial of the NVX-CoV2373 vaccine (NCT04611802), anti-spike binding IgG concentration (spike IgG), anti-RBD binding IgG concentration (RBD IgG), and pseudovirus 50% neutralizing antibody titer (nAb ID50) measured two weeks post-dose two are assessed as correlates of risk and as correlates of protection against COVID-19. Analyses are conducted in the U.S. cohort of baseline SARS-CoV-2 negative per-protocol participants using a case-cohort design that measures the markers from all 12 vaccine recipient breakthrough COVID-19 cases starting 7 days post antibody measurement and from 639 vaccine recipient non-cases. All markers are inversely associated with COVID-19 risk and directly associated with vaccine efficacy. In vaccine recipients with nAb ID50 titers of 50, 100, and 7230 international units (IU50)/ml, vaccine efficacy estimates are 75.7% (49.8%, 93.2%), 81.7% (66.3%, 93.2%), and 96.8% (88.3%, 99.3%). The results support potential cross-vaccine platform applications of these markers for guiding decisions about vaccine approval and use.


Assuntos
COVID-19 , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Imunoglobulina G , SARS-CoV-2 , Eficácia de Vacinas , Ensaios Clínicos Fase III como Assunto
11.
Nat Commun ; 14(1): 302, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36653360

RESUMO

Waves of SARS-CoV-2 infection have resulted from the emergence of viral variants with neutralizing antibody resistance mutations. Simultaneously, repeated antigen exposure has generated affinity matured B cells, producing broadly neutralizing receptor binding domain (RBD)-specific antibodies with activity against emergent variants. To determine how SARS-CoV-2 might escape these antibodies, we subjected chimeric viruses encoding spike proteins from ancestral, BA.1 or BA.2 variants to selection by 40 broadly neutralizing antibodies. We identify numerous examples of epistasis, whereby in vitro selected and naturally occurring substitutions in RBD epitopes that do not confer antibody resistance in the Wuhan-Hu-1 spike, do so in BA.1 or BA.2 spikes. As few as 2 or 3 of these substitutions in the BA.5 spike, confer resistance to nearly all of the 40 broadly neutralizing antibodies, and substantial resistance to plasma from most individuals. Thus, epistasis facilitates the acquisition of resistance to antibodies that remained effective against early omicron variants.


Assuntos
Anticorpos Neutralizantes , COVID-19 , Humanos , SARS-CoV-2/genética , Anticorpos Amplamente Neutralizantes , Epistasia Genética , Glicoproteína da Espícula de Coronavírus/genética , Anticorpos Antivirais
12.
Viruses ; 15(1)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36680213

RESUMO

The rapid emergence of new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants has resulted in the ongoing global coronavirus disease 2019 (COVID-19) pandemic. Thus, the rapid development of a platform to detect a broad range of SARS-CoV-2 variants is essential for successful COVID-19 management. In this study, four SARS-CoV-2 spike protein-specific single-chain variable fragments (scFvs) were isolated from a synthetic antibody library using phage display technology. Following the conversion of these scFvs into monoclonal antibodies (mAbs) (K104.1-K104.4) and production and purification of the mAbs, the antibody pair (K104.1 and K104.2) that exhibited the highest binding affinity (K104.1 and K104.2, 1.3 nM and 1.9 nM) was selected. Biochemical analyses revealed that this antibody pair specifically bound to different sites on the S2 subunit of the spike protein. Furthermore, we developed a highly sensitive sandwich immunoassay using this antibody pair that accurately and quantitatively detected the spike proteins of wild-type SARS-CoV-2 and multiple variants, including Alpha, Beta, Gamma, Delta, Kappa, and Omicron, in the picomolar range. Conclusively, the novel phage display-derived mAbs we have developed may be useful for the rapid and efficient detection of the fast-evolving SARS-CoV-2.


Assuntos
Anticorpos Monoclonais , Bacteriófagos , SARS-CoV-2 , Anticorpos de Cadeia Única , Humanos , Anticorpos Monoclonais/genética , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , SARS-CoV-2/genética , Anticorpos de Cadeia Única/genética , Glicoproteína da Espícula de Coronavírus
13.
Viruses ; 15(1)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36680207

RESUMO

The COVID-19 pandemic has created significant concern for everyone. Recent data from many worldwide reports suggest that most infections are caused by the Omicron variant and its sub-lineages, dominating all the previously emerged variants. The numerous mutations in Omicron's viral genome and its sub-lineages attribute it a larger amount of viral fitness, owing to the alteration of the transmission and pathophysiology of the virus. With a rapid change to the viral structure, Omicron and its sub-variants, namely BA.1, BA.2, BA.3, BA.4, and BA.5, dominate the community with an ability to escape the neutralization efficiency induced by prior vaccination or infections. Similarly, several recombinant sub-variants of Omicron, namely XBB, XBD, and XBF, etc., have emerged, which a better understanding. This review mainly entails the changes to Omicron and its sub-lineages due to it having a higher number of mutations. The binding affinity, cellular entry, disease severity, infection rates, and most importantly, the immune evading potential of them are discussed in this review. A comparative analysis of the Delta variant and the other dominating variants that evolved before Omicron gives the readers an in-depth understanding of the landscape of Omicron's transmission and infection. Furthermore, this review discusses the range of neutralization abilities possessed by several approved antiviral therapeutic molecules and neutralizing antibodies which are functional against Omicron and its sub-variants. The rapid evolution of the sub-variants is causing infections, but the broader aspect of their transmission and neutralization has not been explored. Thus, the scientific community should adopt an elucidative approach to obtain a clear idea about the recently emerged sub-variants, including the recombinant variants, so that effective neutralization with vaccines and drugs can be achieved. This, in turn, will lead to a drop in the number of cases and, finally, an end to the pandemic.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/imunologia , COVID-19/terapia , COVID-19/virologia , Mutação , Pandemias , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus , Evasão da Resposta Imune
14.
Viruses ; 15(1)2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36680278

RESUMO

Genotype IV Japanese encephalitis (JE) virus (GIV JEV) is the least common and most neglected genotype in JEV. We evaluated the growth and pathogenic potential of the GIV strain 19CxBa-83-Cv, which was isolated from a mosquito pool in Bali, Indonesia, in 2019, and serological analyses were also conducted. The growth ability of 19CxBa-83-Cv in Vero cells was intermediate between that of the genotype I (GI) strain Mie/41/2002 and the genotype V (GV) strain Muar, whereas 19CxBa-83-Cv and Mie/41/2002 grew faster than Muar in mouse neuroblastoma cells. The neuroinvasiveness of 19CxBa-83-Cv in mice was higher than that of Mie/41/2002 but lower than that of Muar; however, there were no significant differences in neurovirulence in mice among the three strains. The neutralizing titers of sera from 19CxBa-83-Cv- and Mie/41/2002-inoculated mice against 19CxBa-83-Cv and Mie/41/2002 were similar, whereas the titers against Muar were lower than those of the other two viruses. The neutralizing titers of JE vaccine-inoculated mouse pool serum against 19CxBa-83-Cv and Muar were significantly lower than those against Mie/41/2002. The neutralizing titers against the three viruses were similar in three out of the five serum samples from GI-infected JE patients, although the titers against Mie/41/2002 were higher than those against 19CxBa-83-Cv and Muar in the remaining two sera samples. In summary, we identified the basic characteristics of 19CxBa-83-Cv, but further studies are needed to better understand GIV JEV.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Vírus da Encefalite Japonesa (Subgrupo) , Encefalite Japonesa , Chlorocebus aethiops , Animais , Camundongos , Anticorpos Neutralizantes , Células Vero , Anticorpos Antivirais , Genótipo
15.
Signal Transduct Target Ther ; 8(1): 42, 2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36681668

RESUMO

The Omicron variants of SARS-CoV-2, primarily authenticated in November 2021 in South Africa, has initiated the 5th wave of global pandemics. Here, we systemically examined immunological and metabolic characteristics of Omicron variants infection. We found Omicron resisted to neutralizing antibody targeting receptor binding domain (RBD) of wildtype SARS-CoV-2. Omicron could hardly be neutralized by sera of Corona Virus Disease 2019 (COVID-19) convalescents infected with the Delta variant. Through mass spectrometry on MHC-bound peptidomes, we found that the spike protein of the Omicron variants could generate additional CD8 + T cell epitopes, compared with Delta. These epitopes could induce robust CD8 + T cell responses. Moreover, we found booster vaccination increased the cross-memory CD8 + T cell responses against Omicron. Metabolic regulome analysis of Omicron-specific T cell showed a metabolic profile that promoted the response of memory T cells. Consistently, a greater fraction of memory CD8 + T cells existed in Omicron stimulated peripheral blood mononuclear cells (PBMCs). In addition, CD147 was also a receptor for the Omicron variants, and CD147 antibody inhibited infection of Omicron. CD147-mediated Omicron infection in a human CD147 transgenic mouse model induced exudative alveolar pneumonia. Taken together, our data suggested that vaccination booster and receptor blocking antibody are two effective strategies against Omicron.


Assuntos
COVID-19 , Humanos , Animais , Camundongos , COVID-19/genética , Leucócitos Mononucleares , SARS-CoV-2 , Anticorpos Neutralizantes , Epitopos , Camundongos Transgênicos
16.
Sci Rep ; 13(1): 1222, 2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36681693

RESUMO

The SARS-CoV-2 Omicron (B.1.1.529) Variant of Concern (VOC) and its sub-lineages (including BA.2, BA.4, BA.5, BA.2.12.1) contain spike mutations that confer high level resistance to neutralizing antibodies induced by vaccination with ancestral spike or infection with previously circulating variants. The NVX-CoV2373 vaccine, a protein nanoparticle vaccine containing the ancestral spike sequence, has value in countries with constrained cold-chain requirements. Here we report neutralizing titers following two or three doses of NVX-CoV2373. We show that after two doses, Omicron sub-lineages BA.1 and BA.4/BA.5 were resistant to neutralization by 72% (21/29) and 59% (17/29) of samples respectively. However, after a third dose of NVX-CoV2373, we observed high titers against Omicron BA.1 (GMT: 1,197) and BA.4/BA.5 (GMT: 582), with responses similar in magnitude to those triggered by three doses of an mRNA vaccine. These data are of particular relevance as BA.4/BA.5 is dominating in multiple locations, and highlight the potential utility of the NVX-CoV2373 vaccine as a booster in resource-limited environments.


Assuntos
COVID-19 , Humanos , COVID-19/prevenção & controle , SARS-CoV-2/genética , Anticorpos Neutralizantes , Mutação , Anticorpos Antivirais
17.
Sci Rep ; 13(1): 1263, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36690803

RESUMO

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We evaluated the anti-SARS-CoV-2 antibody levels, anti-spike (S)-immunoglobulin G (IgG) and anti-nucleocapsid (N)-IgG, and the neutralization activity of IgG antibody in COVID­19­convalescent plasma against variants of SARS-CoV-2, alpha, beta, gamma, delta, kappa, omicron and R.1 strains. The study included 30 patients with clinically diagnosed COVID-19. The anti-S-IgG and anti-N-IgG levels ranged from 30.0 to 555.1 and from 10.1 to 752.6, respectively. The neutralization activity (50% inhibition concentration: IC50) for the wild-type Wuhan strain ranged from < 6.3 to 81.5 µg/ml. IgG antibodies were > 100 µg/ml in 18 of 30 (60%) subjects infected with the beta variant. The IC50 values for wild-type and beta variants correlated inversely with anti-S-IgG levels (p < 0.05), but no such correlation was noted with anti-N-IgG. IgG antibodies prevented infectivity and cytopathic effects of six different variants of concern in the cell-based assays of wild-type, alpha, gamma, delta, kappa and R.1 strains, but not that of the beta and omicron strains. IgG is considered the main neutralizing activity in the blood, although other factors may be important in other body tissues.


Assuntos
Antígenos de Grupos Sanguíneos , COVID-19 , Humanos , SARS-CoV-2 , Imunoglobulina G , Anticorpos Antivirais , Anticorpos Neutralizantes
18.
Nat Commun ; 14(1): 17, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36596784

RESUMO

The therapeutic applications of antibodies are manifold and the emergence of SARS-CoV-2 provides a cogent example of the value of rapidly identifying biologically active antibodies. We describe an approach called SLISY (Sequencing-Linked ImmunoSorbent assaY) that in a single experiment can assess the binding specificity of millions of clones, be applied to any screen that links DNA sequence to a potential binding moiety, and requires only a single round of biopanning. We demonstrate this approach using an scFv library applied to cellular and protein targets to identify specific or broadly reacting antibodies. For a cellular target, we use paired HLA knockout cell lines to identify a panel of antibodies specific to HLA-A3. For a protein target, SLISY identifies 1279 clones that bound to the Receptor Binding Domain of the SARS-CoV-2 spike protein, with >40% of tested clones also neutralizing its interaction with ACE2 in in vitro assays. Using a multi-comparison SLISY against the Beta, Gamma, and Delta variants, we recovered clones that exhibited broad-spectrum neutralizing potential in vitro. By evaluating millions of scFvs simultaneously against multiple targets, SLISY allows the rapid identification of candidate scFvs with defined binding profiles facilitating the identification of antibodies with the desired biological activity.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Glicoproteína da Espícula de Coronavírus/genética , Anticorpos Neutralizantes , Anticorpos Antivirais
19.
Proc Natl Acad Sci U S A ; 120(3): e2211132120, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36623200

RESUMO

SARS-CoV-2 vaccines are effective at limiting disease severity, but effectiveness is lower among patients with cancer or immunosuppression. Effectiveness wanes with time and varies by vaccine type. Moreover, previously prescribed vaccines were based on the ancestral SARS-CoV-2 spike-protein that emerging variants may evade. Here, we describe a mechanistic mathematical model for vaccination-induced immunity. We validate it with available clinical data and use it to simulate the effectiveness of vaccines against viral variants with lower antigenicity, increased virulence, or enhanced cell binding for various vaccine platforms. The analysis includes the omicron variant as well as hypothetical future variants with even greater immune evasion of vaccine-induced antibodies and addresses the potential benefits of the new bivalent vaccines. We further account for concurrent cancer or underlying immunosuppression. The model confirms enhanced immunogenicity following booster vaccination in immunosuppressed patients but predicts ongoing booster requirements for these individuals to maintain protection. We further studied the impact of variants on immunosuppressed individuals as a function of the interval between multiple booster doses. Our model suggests possible strategies for future vaccinations and suggests tailored strategies for high-risk groups.


Assuntos
COVID-19 , Neoplasias , Humanos , SARS-CoV-2 , Vacinas contra COVID-19 , COVID-19/prevenção & controle , Anticorpos Antivirais , Anticorpos Neutralizantes
20.
Nat Microbiol ; 8(1): 64-76, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36604507

RESUMO

Pathogenic New World arenaviruses (NWAs) cause haemorrhagic fevers and can have high mortality rates, as shown in outbreaks in South America. Neutralizing antibodies (Abs) are critical for protection from NWAs. Having shown that the MOPEVAC vaccine, based on a hyperattenuated arenavirus, induces neutralizing Abs against Lassa fever, we hypothesized that expression of NWA glycoproteins in this platform might protect against NWAs. Cynomolgus monkeys immunized with MOPEVACMAC, targeting Machupo virus, prevented the lethality of this virus and induced partially NWA cross-reactive neutralizing Abs. We then developed the pentavalent MOPEVACNEW vaccine, expressing glycoproteins from all pathogenic South American NWAs. Immunization of cynomolgus monkeys with MOPEVACNEW induced neutralizing Abs against five NWAs, strong innate followed by adaptive immune responses as detected by transcriptomics and provided sterile protection against Machupo virus and the genetically distant Guanarito virus. MOPEVACNEW may thus be efficient to protect against existing and potentially emerging NWAs.


Assuntos
Arenavirus do Novo Mundo , Animais , Arenavirus do Novo Mundo/metabolismo , Vacinas Combinadas , Macaca fascicularis/metabolismo , Anticorpos Neutralizantes , Glicoproteínas
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