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1.
bioRxiv ; 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38659929

RESUMEN

Cross-species studies are important for a comprehensive understanding of brain functions. However, direct quantitative comparison of behaviors across species presents a significant challenge. To enable such comparisons in perceptual decision-making, we developed a synchronized evidence accumulation task for rodents and humans, by aligning mechanics, stimuli, and training. Rats, mice and humans readily learned the task and exhibited qualitatively similar performance. Quantitative model comparison revealed that all three species employed an evidence accumulation strategy, but differed in speed, accuracy, and key decision parameters. Human performance prioritized accuracy, whereas rodent performance was limited by internal time-pressure. Rats optimized reward rate, while mice appeared to switch between evidence accumulation and other strategies trial-to-trial. Together, these results reveal striking similarities and species-specific priorities in decision-making. Furthermore, the synchronized behavioral framework we present may facilitate future studies involving cross-species comparisons, such as evaluating the face validity of animal models of neuropsychiatric disorders. Highlights: Development of a free response evidence accumulation task for rats and miceSynchronized video game allows direct comparisons with humansRat, mouse and human behavior are well fit by the same decision modelsModel parameters reveal species-specific priorities in accumulation strategy.

2.
Commun Biol ; 6(1): 1250, 2023 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-38082099

RESUMEN

The ongoing evolution of SARS-CoV-2 into more easily transmissible and infectious variants has provided unprecedented insight into mutations enabling immune escape. Understanding how these mutations affect the dynamics of antibody-antigen interactions is crucial to the development of broadly protective antibodies and vaccines. Here we report the characterization of a potent neutralizing antibody (N3-1) identified from a COVID-19 patient during the first disease wave. Cryogenic electron microscopy revealed a quaternary binding mode that enables direct interactions with all three receptor-binding domains of the spike protein trimer, resulting in extraordinary avidity and potent neutralization of all major variants of concern until the emergence of Omicron. Structure-based rational design of N3-1 mutants improved binding to all Omicron variants but only partially restored neutralization of the conformationally distinct Omicron BA.1. This study provides new insights into immune evasion through changes in spike protein dynamics and highlights considerations for future conformationally biased multivalent vaccine designs.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética , Anticuerpos Neutralizantes
3.
Front Oncol ; 13: 1169458, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37256179

RESUMEN

Background: Due to the effectiveness and safety, acupuncture, one of the traditional therapies of Chinese medicine, has been widely used in clinical practice globally. A few systematic review or meta-analyses have proved its effectiveness and safety towards patients with cancer pain, while there are no syntheses among those evidence. The aim of this scoping review is to summarize the evidence from systematic reviews of acupuncture for the treatment of cancer pain and evaluate the breadth and methodological quality of these evidence as well. Methods: The scoping review process was guided by the methodology framework of Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews (PRISMA ScR) and "Arkseyand O'Malley six-stage framework". Electronic searches were carried out in several online databases from inception to Jan 2022. Systematic reviews and meta-analyses that involve any type of acupuncture for patients with cancer pain will be included. A pair of reviewers independently screened full texts. Moreover, review characteristics were extracted, and methodological quality was assessed using the AMSTAR 2 tool. Results: Twenty-five systematic reviews and meta-analyses were included. Manual acupuncture is the most frequently included types of test group intervention (48%), followed by acupuncture + medicine (28%), and auricular acupuncture (12%). All the reviews have declared that acupuncture is an effective method for cancer pain treatment. Eleven reviews (44%) aiming at evaluating the safety also have confirmed that acupuncture is safe for treating cancer pain. However, most included studies were conducted in China. With certain geographical limitations, the findings were not representative within the region. The results of our review may owe to the synthesis of all kinds of cancer pain, and only 2 reviews described the type of cancer pain in detail. Conclusions: This scoping review synthesizes and evaluates existing evidence of acupuncture for cancer pain. From this scoping review of systematic reviews and meta-analyses, there are clear recommendations for future studies: expanding the region of research in the world and trying to conduct the study of different types of cancer pain in details as much as possible. Evidences of acupuncture for cancer pain can inform clinical decision-making. Systematic review registration: https://inplasy.com/inplasy-2022-1-0073/, identifier INPLASY202210073.

4.
Emerg Microbes Infect ; 12(1): 2209208, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37114433

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to evolve after its emergence. Given its importance in viral infection and vaccine development, mutations in the viral Spike gene have been studied extensively; however, the impact of mutations outside the Spike gene are poorly understood. Here, we report that a triple deletion (ΔSGF or ΔLSG) in nonstructural protein 6 (nsp6) independently acquired in Alpha and Omicron sublineages of SARS-CoV-2 augments nsp6-mediated antagonism of type-I interferon (IFN-I) signaling. Specifically, these triple deletions enhance the ability of mutant nsp6 to suppress phosphorylation of STAT1 and STAT2. A parental SARS-CoV-2 USA-WA1/2020 strain containing the nsp6 ΔSGF deletion (ΔSGF-WA1) shows reduced susceptibility to IFN-I treatment in vitro, outcompetes the parental strain in human primary airway cultures, and increases virulence in mice; however, the ΔSGF-WA1 virus is less virulent than the Alpha variant (which has the nsp6 ΔSGF deletion and additional mutations in other genes). Analyses of host responses from ΔSGF-WA1-infected mice and primary airway cultures reveal activation of pathways indicative of a cytokine storm. These results provide evidence that mutations outside the Spike protein affect virus-host interactions and may alter pathogenesis of SARS-CoV-2 variants in humans.


Asunto(s)
COVID-19 , Interferón Tipo I , Humanos , Animales , Ratones , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Interferón Tipo I/metabolismo , Mutación , Glicoproteína de la Espiga del Coronavirus
5.
PLoS Pathog ; 19(4): e1011286, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37075076

RESUMEN

Flaviviruses continue to emerge as global health threats. There are currently no Food and Drug Administration (FDA) approved antiviral treatments for flaviviral infections. Therefore, there is a pressing need to identify host and viral factors that can be targeted for effective therapeutic intervention. Type I interferon (IFN-I) production in response to microbial products is one of the host's first line of defense against invading pathogens. Cytidine/uridine monophosphate kinase 2 (CMPK2) is a type I interferon-stimulated gene (ISG) that exerts antiviral effects. However, the molecular mechanism by which CMPK2 inhibits viral replication is unclear. Here, we report that CMPK2 expression restricts Zika virus (ZIKV) replication by specifically inhibiting viral translation and that IFN-I- induced CMPK2 contributes significantly to the overall antiviral response against ZIKV. We demonstrate that expression of CMPK2 results in a significant decrease in the replication of other pathogenic flaviviruses including dengue virus (DENV-2), Kunjin virus (KUNV) and yellow fever virus (YFV). Importantly, we determine that the N-terminal domain (NTD) of CMPK2, which lacks kinase activity, is sufficient to restrict viral translation. Thus, its kinase function is not required for CMPK2's antiviral activity. Furthermore, we identify seven conserved cysteine residues within the NTD as critical for CMPK2 antiviral activity. Thus, these residues may form an unknown functional site in the NTD of CMPK2 contributing to its antiviral function. Finally, we show that mitochondrial localization of CMPK2 is required for its antiviral effects. Given its broad antiviral activity against flaviviruses, CMPK2 is a promising potential pan-flavivirus inhibitor.


Asunto(s)
Nucleósido-Fosfato Quinasa , Replicación Viral , Virus Zika , Virus Zika/fisiología , Células Vero , Chlorocebus aethiops , Animales , Humanos , Nucleósido-Fosfato Quinasa/metabolismo , Interferón Tipo I/metabolismo , Flavivirus/fisiología , Mitocondrias , Biosíntesis de Proteínas
6.
Antiviral Res ; 212: 105574, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36905944

RESUMEN

AT-752 is a guanosine analogue prodrug active against dengue virus (DENV). In infected cells, it is metabolized into 2'-methyl-2'-fluoro guanosine 5'-triphosphate (AT-9010) which inhibits RNA synthesis in acting as a RNA chain terminator. Here we show that AT-9010 has several modes of action on DENV full-length NS5. AT-9010 does not inhibit the primer pppApG synthesis step significantly. However, AT-9010 targets two NS5-associated enzyme activities, the RNA 2'-O-MTase and the RNA-dependent RNA polymerase (RdRp) at its RNA elongation step. Crystal structure and RNA methyltransferase (MTase) activities of the DENV 2 MTase domain in complex with AT-9010 at 1.97 Å resolution shows the latter bound to the GTP/RNA-cap binding site, accounting for the observed inhibition of 2'-O but not N7-methylation activity. AT-9010 is discriminated ∼10 to 14-fold against GTP at the NS5 active site of all four DENV1-4 NS5 RdRps, arguing for significant inhibition through viral RNA synthesis termination. In Huh-7 cells, DENV1-4 are equally sensitive to AT-281, the free base of AT-752 (EC50 ≈ 0.50 µM), suggesting broad spectrum antiviral properties of AT-752 against flaviviruses.


Asunto(s)
Virus del Dengue , Dengue , Humanos , Dengue/tratamiento farmacológico , Virus del Dengue/fisiología , Guanosina/farmacología , Guanosina/metabolismo , Guanosina Trifosfato/metabolismo , ARN Viral/metabolismo , Proteínas no Estructurales Virales/genética , Replicación Viral
7.
Emerg Microbes Infect ; 12(1): e2161422, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36594261

RESUMEN

The rapid evolution of SARS-CoV-2 Omicron sublineages mandates a better understanding of viral replication and cross-neutralization among these sublineages. Here we used K18-hACE2 mice and primary human airway cultures to examine the viral fitness and antigenic relationship among Omicron sublineages. In both K18-hACE2 mice and human airway cultures, Omicron sublineages exhibited a replication order of BA.5 ≥ BA.2 ≥ BA.2.12.1 > BA.1; no difference in body weight loss was observed among different sublineage-infected mice. The BA.1-, BA.2-, BA.2.12.1-, and BA.5-infected mice developed distinguishable cross-neutralizations against Omicron sublineages, but exhibited little neutralization against the index virus (i.e. USA-WA1/2020) or the Delta variant. Surprisingly, the BA.5-infected mice developed higher neutralization activity against heterologous BA.2 and BA.2.12.1 than that against homologous BA.5; serum neutralizing titres did not always correlate with viral replication levels in infected animals. Our results revealed a distinct antigenic cartography of Omicron sublineages and support the bivalent vaccine approach.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Animales , Ratones , SARS-CoV-2/genética , Melfalán , Anticuerpos Antivirales , Anticuerpos Neutralizantes
8.
Nat Med ; 29(2): 344-347, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36473500

RESUMEN

The newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron sublineages, including the BA.2-derived BA.2.75.2 and the BA.5-derived BQ.1.1 and XBB.1, have accumulated additional spike mutations that may affect vaccine effectiveness. Here we report neutralizing activities of three human serum panels collected from individuals 23-94 days after dose 4 of a parental mRNA vaccine; 14-32 days after a BA.5 bivalent booster from individuals with 2-4 previous doses of parental mRNA vaccine; or 14-32 days after a BA.5 bivalent booster from individuals with previous SARS-CoV-2 infection and 2-4 doses of parental mRNA vaccine. The results showed that a BA.5 bivalent booster elicited a high neutralizing titer against BA.4/5 measured at 14-32 days after boost; however, the BA.5 bivalent booster did not produce robust neutralization against the newly emerged BA.2.75.2, BQ.1.1 or XBB.1. Previous infection substantially enhanced the magnitude and breadth of BA.5 bivalent booster-elicited neutralization. Our data support a vaccine update strategy that future boosters should match newly emerged circulating SARS-CoV-2 variants.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Vacunas Sintéticas , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacunas de ARNm
10.
Nat Commun ; 13(1): 5552, 2022 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-36138032

RESUMEN

One major limitation of neutralizing antibody-based COVID-19 therapy is the requirement of costly cocktails to reduce emergence of antibody resistance. Here we engineer two bispecific antibodies (bsAbs) using distinct designs and compared them with parental antibodies and their cocktail. Single molecules of both bsAbs block the two epitopes targeted by parental antibodies on the receptor-binding domain (RBD). However, bsAb with the IgG-(scFv)2 design (14-H-06) but not the CrossMAb design (14-crs-06) shows increased antigen-binding and virus-neutralizing activities against multiple SARS-CoV-2 variants as well as increased breadth of neutralizing activity compared to the cocktail. X-ray crystallography and cryo-EM reveal distinct binding models for individual cocktail antibodies, and computational simulations suggest higher inter-spike crosslinking potentials by 14-H-06 than 14-crs-06. In mouse models of infections by SARS-CoV-2 and multiple variants, 14-H-06 exhibits higher or equivalent therapeutic efficacy than the cocktail. Rationally engineered bsAbs represent a cost-effective alternative to antibody cocktails and a promising strategy to improve potency and breadth.


Asunto(s)
Anticuerpos Biespecíficos , Tratamiento Farmacológico de COVID-19 , Animales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Epítopos , Inmunoglobulina G , Ratones , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus
11.
Artículo en Inglés | MEDLINE | ID: mdl-35966744

RESUMEN

Background. In the past, moxibustion has been widely used to treat endocrine system disorders, but evidence of its effectiveness is scarce at this point. The aim of this multicenter, randomized, controlled trial is to evaluate the efficacy and safety of treating menopausal obesity with moxibustion. Methods/Design. There are six centers taking part in this randomized, controlled, parallel trial. A total of 216 patients with menopausal obesity will be randomly divided into two equal groups: the "moxibustion for harmonization of Yin and Yang" group and the gentle moxibustion group. A 12-week study period with moxibustion will be preceded by a 1-week baseline, followed by a 12-week follow-up. We will conduct an interim analysis to determine whether or not the treatment is efficacious and safe after 216 participants have completed a 12-week treatment period. Evaluations will be conducted at weeks 0, 4, 8, 12, 18, and 24. The main outcome is waist circumference (WC), and the rate of WC reduction will be compared to the baseline. An intention-to-treat analysis will be performed with a two-sided P value of <0.05 considered significant. Participants who withdraw from the trial will be analyzed according to the intention-to-treat formula (ITT). Discussion. These results will be used to support selecting the right moxibustion prescription and guiding the improvement of clinical efficacy. This trial will provide convincing evidence of moxibustion's effectiveness and safety in the treatment of obesity by "moxibustion for harmonization of Yin and Yang," which will be conducive to the promotion and clinical application of the theory of "moxibustion for harmonization of Yin and Yang." Trial Registration. This trial is registered with Clinical Trials.gov: NCT04943705 (registered on June 27, 2021).

12.
Cell Host Microbe ; 30(9): 1242-1254.e6, 2022 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-35988543

RESUMEN

The worldwide spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to the repeated emergence of variants of concern. For the Omicron variant, sub-lineages BA.1 and BA.2, respectively, contain 33 and 29 nonsynonymous and indel spike protein mutations. These amino acid substitutions and indels are implicated in increased transmissibility and enhanced immune evasion. By reverting individual spike mutations of BA.1 or BA.2, we characterize the molecular effects of the Omicron spike mutations on expression, ACE2 receptor affinity, and neutralizing antibody recognition. We identified key mutations enabling escape from neutralizing antibodies at a variety of epitopes. Stabilizing mutations in the N-terminal and S2 domains of the spike protein can compensate for destabilizing mutations in the receptor binding domain, enabling the record number of mutations in Omicron. Our results provide a comprehensive account of the mutational effects in the Omicron spike protein and illustrate previously uncharacterized mechanisms of host evasion.


Asunto(s)
COVID-19 , Glicoproteína de la Espiga del Coronavirus , Enzima Convertidora de Angiotensina 2/genética , Anticuerpos Neutralizantes/genética , Anticuerpos Antivirales , Epítopos , Humanos , Glicoproteínas de Membrana , Mutación , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética , Proteínas del Envoltorio Viral
13.
Emerg Microbes Infect ; 11(1): 1828-1832, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35792746

RESUMEN

Distinct SARS-CoV-2 Omicron sublineages have evolved showing increased fitness and immune evasion than the original Omicron variant BA.1. Here, we report the neutralization activity of sera from BNT162b2 vaccinated individuals or unimmunized Omicron BA.1-infected individuals against Omicron sublineages and "Deltacron" variant (XD). BNT162b2 post-dose 3 immune sera neutralized USA-WA1/2020, Omicron BA.1-, BA.2-, BA.2.12.1-, BA.3-, BA.4/5-, and XD-spike SARS-CoV-2s with geometric mean titres (GMTs) of 1335, 393, 298, 315, 216, 103, and 301, respectively; thus, BA.4/5 SARS-CoV-2 spike variant showed the highest propensity to evade vaccine neutralization compared to the original Omicron variants BA.1. BA.1-convalescent sera neutralized USA-WA1/2020, BA.1-, BA.2-, BA.2.12.1-, BA.3-, BA.4/5-, and Deltacron-spike SARS-CoV-2s with GMTs of 15, 430, 110, 109, 102, 25, and 284, respectively. The unique mutation F486V in the BA.4/5 spike contributes to the increased evasion of antibody neutralization by sublineage BA.4/5. The low neutralization titres of vaccinated sera or convalescent sera from BA.1 infected individuals against the emerging and rapidly spreading Omicron BA.4/5 variants provide important results for consideration in the selection of an updated vaccine in the current Omicron wave.Trial registration: ClinicalTrials.gov; identifier: NCT04368728.


Asunto(s)
COVID-19 , Vacunas Virales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacuna BNT162 , COVID-19/prevención & control , COVID-19/terapia , Humanos , Inmunización Pasiva , Glicoproteínas de Membrana/genética , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética , Proteínas del Envoltorio Viral , Sueroterapia para COVID-19
14.
Nat Commun ; 13(1): 4350, 2022 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-35896523

RESUMEN

The evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in the emergence of new variant lineages that have exacerbated the COVID-19 pandemic. Some of those variants were designated as variants of concern/interest (VOC/VOI) by national or international authorities based on many factors including their potential impact on vaccine-mediated protection from disease. To ascertain and rank the risk of VOCs and VOIs, we analyze the ability of 14 variants (614G, Alpha, Beta, Gamma, Delta, Epsilon, Zeta, Eta, Theta, Iota, Kappa, Lambda, Mu, and Omicron) to escape from mRNA vaccine-induced antibodies. The variants show differential reductions in neutralization and replication by post-vaccination sera. Although the Omicron variant (BA.1, BA.1.1, and BA.2) shows the most escape from neutralization, sera collected after a third dose of vaccine (booster sera) retain moderate neutralizing activity against that variant. Therefore, vaccination remains an effective strategy during the COVID-19 pandemic.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Pruebas de Neutralización , Pandemias , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus , Vacunas Sintéticas , Vacunas de ARNm
15.
Nat Commun ; 13(1): 4337, 2022 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-35896528

RESUMEN

We report a live-attenuated SARS-CoV-2 vaccine candidate with (i) re-engineered viral transcription regulator sequences and (ii) deleted open-reading-frames (ORF) 3, 6, 7, and 8 (∆3678). The ∆3678 virus replicates about 7,500-fold lower than wild-type SARS-CoV-2 on primary human airway cultures, but restores its replication on interferon-deficient Vero-E6 cells that are approved for vaccine production. The ∆3678 virus is highly attenuated in both hamster and K18-hACE2 mouse models. A single-dose immunization of the ∆3678 virus protects hamsters from wild-type virus challenge and transmission. Among the deleted ORFs in the ∆3678 virus, ORF3a accounts for the most attenuation through antagonizing STAT1 phosphorylation during type-I interferon signaling. We also developed an mNeonGreen reporter ∆3678 virus for high-throughput neutralization and antiviral testing. Altogether, the results suggest that ∆3678 SARS-CoV-2 may serve as a live-attenuated vaccine candidate and a research tool for potential biosafety level-2 use.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Animales , Antivirales , COVID-19/prevención & control , Cricetinae , Humanos , Interferones , Ratones , SARS-CoV-2/genética , Vacunas Atenuadas , Replicación Viral
16.
Nat Commun ; 13(1): 3602, 2022 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-35739094

RESUMEN

The newly emerged Omicron SARS-CoV-2 has several distinct sublineages including BA.1, BA.2, and BA.3. BA.1 accounts for the initial surge and is being replaced by BA.2, whereas BA.3 is at a low prevalence at this time. Here we report the neutralization of BNT162b2-vaccinated sera (collected 1 month after dose 3) against the three Omicron sublineages. To facilitate the neutralization testing, we have engineered the complete BA.1, BA.2, or BA.3 spike into an mNeonGreen USA-WA1/2020 SRAS-CoV-2. All BNT162b2-vaccinated sera neutralize USA-WA1/2020, BA.1-, BA.2-, and BA.3-spike SARS-CoV-2s with titers of >20; the neutralization geometric mean titers (GMTs) against the four viruses are 1211, 336, 300, and 190, respectively. Thus, the BA.1-, BA.2-, and BA.3-spike SARS-CoV-2s are 3.6-, 4.0-, and 6.4-fold less efficiently neutralized than the USA-WA1/2020, respectively. Our data have implications in vaccine strategy and understanding the biology of Omicron sublineages.


Asunto(s)
COVID-19 , Vacunas Virales , Anticuerpos Antivirales , Vacuna BNT162 , COVID-19/prevención & control , Humanos , SARS-CoV-2
17.
Viruses ; 14(6)2022 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-35746682

RESUMEN

A robust serological test to measure neutralizing antibodies against SARS-CoV-2 in biosafety level-2 (BSL-2) laboratories is useful for monitoring antibody response after vaccination or natural infection. The gold standard assay is the conventional plaque reduction neutralization test (PRNT) which requires extensive labor, live viruses, and BSL-3 facilities. Recently, we developed a novel single-round infection fluorescent SARS-CoV-2 virus (SFV) that can be safely used at BSL-2 laboratories for high-throughput neutralization and antiviral testing. In this study, we evaluated the performance of the neutralization test using this SFV with 80 PRNT-positive and 92 PRNT-negative clinical serum or plasma specimens. The SFV neutralization test (SFVNT) has 100% sensitivity and specificity compared to the PRNT. Furthermore, the neutralizing titers generated by the SFVNT and PRNT are highly correlated, with R2 = 0.903 (p < 0.0001). Due to high sensitivity, specificity, accuracy, and reproducibility, the SFVNT can be deployed for the large-scale testing of COVID-19 patients or vaccinated people in general lab settings.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/diagnóstico , Prueba Serológica para COVID-19 , Contención de Riesgos Biológicos , Humanos , Laboratorios , Pruebas de Neutralización , Reproducibilidad de los Resultados
18.
Cell Rep ; 39(7): 110829, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35550680

RESUMEN

We report that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta spike mutation P681R plays a key role in the Alpha-to-Delta variant replacement during the coronavirus disease 2019 (COVID-19) pandemic. Delta SARS-CoV-2 efficiently outcompetes the Alpha variant in human lung epithelial cells and primary human airway tissues. The Delta spike mutation P681R is located at a furin cleavage site that separates the spike 1 (S1) and S2 subunits. Reverting the P681R mutation to wild-type P681 significantly reduces the replication of the Delta variant to a level lower than the Alpha variant. Mechanistically, the Delta P681R mutation enhances the cleavage of the full-length spike to S1 and S2, which could improve cell-surface-mediated virus entry. In contrast, the Alpha spike also has a mutation at the same amino acid (P681H), but the cleavage of the Alpha spike is reduced compared with the Delta spike. Our results suggest P681R as a key mutation in enhancing Delta-variant replication via increased S1/S2 cleavage.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/genética , Humanos , Mutación/genética , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética
19.
Nat Commun ; 13(1): 2956, 2022 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-35618703

RESUMEN

The Omicron SARS-CoV-2 has several distinct sublineages, among which sublineage BA.1 is responsible for the initial Omicron surge and is now being replaced by BA.2 worldwide, whereas BA.3 is currently at a low frequency. The ongoing BA.1-to-BA.2 replacement underscores the importance to understand the cross-neutralization among the three Omicron sublineages. Here we test the neutralization of BA.1-infected human sera against BA.2, BA.3, and USA/WA1-2020 (a strain isolated in late January 2020). The BA.1-infected sera neutralize BA.1, BA.2, BA.3, and USA/WA1-2020 SARS-CoV-2s with geometric mean titers (GMTs) of 445, 107, 102, and 16, respectively. Thus, the neutralizing GMTs against heterologous BA.2, BA.3, and USA/WA1-2020 are 4.2-, 4.4-, and 28.4-fold lower than the GMT against homologous BA.1, respectively. These findings have implications in COVID-19 vaccine strategy.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Antivirales , Vacunas contra la COVID-19 , Humanos , Pruebas de Neutralización
20.
NPJ Vaccines ; 7(1): 41, 2022 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-35396516

RESUMEN

BNT162b2-elicited human sera neutralize the currently dominant Delta SARS-CoV-2 variant. Here, we report the ability of 20 human sera, drawn 2 or 4 weeks after two doses of BNT162b2, to neutralize USA-WA1/2020 SARS-CoV-2 bearing variant spikes from Delta plus (Delta-AY.1, Delta-AY.2), Delta-∆144 (Delta with the Y144 deletion of the Alpha variant), Lambda, B.1.1.519, Theta, and Mu lineage viruses. Geometric mean plaque reduction neutralization titers against Delta-AY.1, Delta-AY.2, and Mu viruses are slightly lower than against USA-WA1/2020, but all sera neutralize the variant viruses to titers of ≥80, and neutralization titers against the Delta-∆144, Lambda, B.1.1.519 and Theta variants not significantly reduced relative to those against USA-WA1/2020. The susceptibility of Delta plus, Lambda, B.1.1.519, Theta, Mu, and other variants to neutralization by the sera indicates that antigenic change has not led to virus escape from vaccine-elicited neutralizing antibodies and supports ongoing mass immunization with BNT162b2 to control the variants and to minimize the emergence of new variants.

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