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1.
Signal Transduct Target Ther ; 9(1): 114, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678055

RESUMO

Developing a mucosal vaccine against SARS-CoV-2 is critical for combatting the epidemic. Here, we investigated long-term immune responses and protection against SARS-CoV-2 for the intranasal vaccination of a triple receptor-binding domain (RBD) scaffold protein (3R-NC) adjuvanted with a flagellin protein (KFD) (3R-NC + KFDi.n). In mice, the vaccination elicited RBD-specific broad-neutralizing antibody responses in both serum and mucosal sites sustained at high level over a year. This long-lasting humoral immunity was correlated with the presence of long-lived RBD-specific IgG- and IgA-producing plasma cells, alongside the Th17 and Tfh17-biased T-cell responses driven by the KFD adjuvant. Based upon these preclinical findings, an open labeled clinical trial was conducted in individuals who had been primed with the inactivated SARS-CoV-2 (IAV) vaccine. With a favorable safety profile, the 3R-NC + KFDi.n boost elicited enduring broad-neutralizing IgG in plasma and IgA in salivary secretions. To meet the challenge of frequently emerged variants, we further designed an updated triple-RBD scaffold protein with mutated RBD combinations, which can induce adaptable antibody responses to neutralize the newly emerging variants, including JN.1. Our findings highlight the potential of the KFD-adjuvanted triple-RBD scaffold protein is a promising prototype for the development of a mucosal vaccine against SARS-CoV-2 infection.


Assuntos
Administração Intranasal , Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Flagelina , SARS-CoV-2 , SARS-CoV-2/imunologia , Humanos , Flagelina/imunologia , Flagelina/genética , Flagelina/administração & dosagem , COVID-19/prevenção & controle , COVID-19/imunologia , Animais , Camundongos , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Anticorpos Neutralizantes/imunologia , Feminino , Anticorpos Antivirais/imunologia , Vacinação , Masculino , Adulto , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Imunoglobulina A/imunologia , Pessoa de Meia-Idade
2.
J Med Virol ; 96(4): e29611, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38639305

RESUMO

While micronutrients are crucial for immune function, their impact on humoral responses to inactivated COVID-19 vaccination remains unclear. We investigated the associations between seven key micronutrients and antibody responses in 44 healthy adults with two doses of an inactivated COVID-19 vaccine. Blood samples were collected pre-vaccination and 28 days post-booster. We measured circulating minerals (iron, zinc, copper, and selenium) and vitamins (A, D, and E) concentrations alongside antibody responses and assessed their associations using linear regression analyses. Our analysis revealed inverse associations between blood iron and zinc concentrations and anti-SARS-CoV-2 IgM antibody binding affinity (AUC for iron: ß = -258.21, p < 0.0001; zinc: ß = -17.25, p = 0.0004). Notably, antibody quality presented complex relationships. Blood selenium was positively associated (ß = 18.61, p = 0.0030), while copper/selenium ratio was inversely associated (ß = -1.36, p = 0.0055) with the neutralizing ability against SARS-CoV-2 virus at a 1:10 plasma dilution. There was no significant association between circulating micronutrient concentrations and anti-SARS-CoV-2 IgG binding affinity. These findings suggest that circulating iron, zinc, and selenium concentrations and copper/selenium ratio, may serve as potential biomarkers for both quantity (binding affinity) and quality (neutralization) of humoral responses after inactivated COVID-19 vaccination. Furthermore, they hint at the potential of pre-vaccination dietary interventions, such as selenium supplementation, to improve vaccine efficacy. However, larger, diverse studies are needed to validate these findings. This research advances the understanding of the impact of micronutrients on vaccine response, offering the potential for personalized vaccination strategies.


Assuntos
COVID-19 , Selênio , Oligoelementos , Adulto , Humanos , Micronutrientes , Vacinas contra COVID-19 , Cobre , COVID-19/prevenção & controle , SARS-CoV-2 , Zinco , Ferro , Vacinação , Anticorpos Antivirais , Anticorpos Neutralizantes
3.
J Infect ; 88(3): 106118, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342382

RESUMO

OBJECTIVES: The respiratory tract is the portal of entry for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although a variety of respiratory pathogens other than SARS-CoV-2 have been associated with severe cases of COVID-19 disease, the dynamics of the upper respiratory microbiota during disease the course of disease, and how they impact disease manifestation, remain uncertain. METHODS: We collected 349 longitudinal upper respiratory samples from a cohort of 65 COVID-19 patients (cohort 1), 28 samples from 28 recovered COVID-19 patients (cohort 2), and 59 samples from 59 healthy controls (cohort 3). All COVID-19 patients originated from the earliest stage of the epidemic in Wuhan. Based on a modified clinical scale, the disease course was divided into five clinical disease phases (pseudotimes): "Healthy" (pseudotime 0), "Incremental" (pseudotime 1), "Critical" (pseudotime 2), "Complicated" (pseudotime 3), "Convalescent" (pseudotime 4), and "Long-term follow-up" (pseudotime 5). Using meta-transcriptomics, we investigated the features and dynamics of transcriptionally active microbes in the upper respiratory tract (URT) over the course of COVID-19 disease, as well as its association with disease progression and clinical outcomes. RESULTS: Our results revealed that the URT microbiome exhibits substantial heterogeneity during disease course. Two clusters of microbial communities characterized by low alpha diversity and enrichment for multiple pathogens or potential pathobionts (including Acinetobacter and Candida) were associated with disease progression and a worse clinical outcome. We also identified a series of microbial indicators that classified disease progression into more severe stages. Longitudinal analysis revealed that although the microbiome exhibited complex and changing patterns during COVID-19, a restoration of URT microbiomes from early dysbiosis toward more diverse status in later disease stages was observed in most patients. In addition, a group of potential pathobionts were strongly associated with the concentration of inflammatory indicators and mortality. CONCLUSION: This study revealed strong links between URT microbiome dynamics and disease progression and clinical outcomes in COVID-19, implying that the treatment of severe disease should consider the full spectrum of microbial pathogens present.


Assuntos
COVID-19 , Microbiota , Humanos , SARS-CoV-2 , Nariz , Progressão da Doença
4.
Nucleic Acids Res ; 52(5): 2142-2156, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38340342

RESUMO

Human DNA topoisomerase 1 (Top1) is a crucial enzyme responsible for alleviating torsional stress on DNA during transcription and replication, thereby maintaining genome stability. Previous researches had found that non-working Top1 interacted extensively with chromosomal DNA in human cells. However, the reason for its retention on chromosomal DNA remained unclear. In this study, we discovered a close association between Top1 and chromosomal DNA, specifically linked to the presence of G-quadruplex (G4) structures. G4 structures, formed during transcription, trap Top1 and hinder its ability to relax neighboring DNAs. Disruption of the Top1-G4 interaction using G4 ligand relieved the inhibitory effect of G4 on Top1 activity, resulting in a further reduction of R-loop levels in cells. Additionally, the activation of Top1 through the use of a G4 ligand enhanced the toxicity of Top1 inhibitors towards cancer cells. Our study uncovers a negative regulation mechanism of human Top1 and highlights a novel pathway for activating Top1.


Assuntos
DNA Topoisomerases Tipo I , Quadruplex G , Transcrição Gênica , Humanos , DNA/química , Replicação do DNA , DNA Topoisomerases Tipo I/metabolismo , Ligantes , Inibidores da Topoisomerase I/farmacologia
5.
Vaccine ; 41(52): 7641-7646, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38016845

RESUMO

A third dose of inactivated virus vaccine (IVV) boosts neutralizing antibodies, reducing SARS-CoV-2 transmission rate and COVID-19 severity. However, the impact of RBD-elicited antibodies and their neutralizing activity by the boost of IVV is unknown. We investigated the impact of IVV's boost shot on RBD-elicited antibodies and their neutralizing activity in 18 subjects receiving the second and third IVV doses. Using an RBD antibodies depletion assay, we assessed the neutralizing activity of RBD-elicited antibodies. After the second dose, RBD-antigen elicitation accounted for ∼60% of neutralizing activity, which increased to 82% after the IVV boost against ancestral SARS-CoV-2. Depleting class 3 and class 4-specific antibodies with the Beta-RBD protein revealed that NAbs targeting RBD class 1 and class 2 subdomains increased from 57% to 75% post-boost. These findings highlight the significant enhancement of RBD-specific antibodies, especially against RBD class 1 and class 2, with IVV booster doses. Our study offers valuable insights for optimizing COVID-19 vaccine strategies.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Epitopos , Vacinas de Produtos Inativados , Vacinas contra COVID-19 , COVID-19/prevenção & controle , Anticorpos , Anticorpos Bloqueadores , Anticorpos Neutralizantes , Anticorpos Antivirais
6.
J Med Virol ; 95(9): e29083, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37698033

RESUMO

The human gut microbiome varies substantially across individuals and populations and differentially tames our immunity at steady-state. Hence, we hypothesize that the large heterogeneity of gut microbiomes at steady-state may shape our baseline immunity differentially, and then mediate discrepant immune responses and symptoms when one encounters a viral infection, such as SARS-CoV-2 infection. To validate this hypothesis, we conducted an exploratory, longitudinal microbiome-COVID-19 study involving homogenous young participants from two geographically different regions in China. Subjects were recruited and sampled of fecal specimens before the 3-week surge window of COVID-19 (between December 11 and December 31, 2022) in China, and then were followed up for assessment of COVID-19 and post-COVID-19 manifestations. Our data showed that the baseline gut microbiome composition was intricately associated with different COVID-19 manifestations, particularly gastrointestinal involvement and post-COVID-19 lingering symptoms, in both an individual- and population-dependent manner. Our study intriguingly for the first time highlight that the gut microbiome at steady-state may prepare us differentially for weathering a respiratory viral infection.


Assuntos
COVID-19 , Microbioma Gastrointestinal , Microbiota , Humanos , SARS-CoV-2 , China/epidemiologia
7.
Front Immunol ; 14: 1195533, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37654488

RESUMO

Background: Pre-existing cross-reactive immunity among different coronaviruses, also termed immune imprinting, may have a comprehensive impact on subsequent SARS-CoV-2 infection and COVID-19 vaccination effectiveness. Here, we aim to explore the interplay between pre-existing seasonal coronaviruses (sCoVs) antibodies and the humoral immunity induced by COVID-19 vaccination. Methods: We first collected serum samples from healthy donors prior to COVID-19 pandemic and individuals who had received COVID-19 vaccination post-pandemic in China, and the levels of IgG antibodies against sCoVs and SARS-CoV-2 were detected by ELISA. Wilcoxon rank sum test and chi-square test were used to compare the difference in magnitude and seropositivity rate between two groups. Then, we recruited a longitudinal cohort to collect serum samples before and after COVID-19 vaccination. The levels of IgG antibodies against SARS-CoV-2 S, S1, S2 and N antigen were monitored. Association between pre-existing sCoVs antibody and COVID-19 vaccination-induced antibodies were analyzed by Spearman rank correlation. Results: 96.0% samples (339/353) showed the presence of IgG antibodies against at least one subtype of sCoVs. 229E and OC43 exhibited the highest seroprevalence rates at 78.5% and 72.0%, respectively, followed by NL63 (60.9%) and HKU1 (52.4%). The levels of IgG antibodies against two ß coronaviruses (OC43 and HKU1) were significantly higher in these donors who had inoculated with COVID-19 vaccines compared to pre-pandemic healthy donors. However, we found that COVID-19 vaccine-induced antibody levels were not significant different between two groups with high levelor low level of pre-existing sCoVs antibody among the longitudinal cohort. Conclusion: We found a high prevalence of antibodies against sCoVs in Chinese population. The immune imprinting by sCoVs could be reactivated by COVID-19 vaccination, but it did not appear to be a major factor affecting the immunogenicity of COVID-19 vaccine. These findings will provide insights into understanding the impact of immune imprinting on subsequent multiple shots of COVID-19 vaccines.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Pandemias , Estações do Ano , Estudos Soroepidemiológicos , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , Imunoglobulina G
8.
Emerg Microbes Infect ; 12(2): 2245931, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37542407

RESUMO

Yearly epidemics of seasonal influenza cause an enormous disease burden around the globe. An understanding of the rules behind the immune response with repeated vaccination still presents a significant challenge, which would be helpful for optimizing the vaccination strategy. In this study, 34 healthy volunteers with 16 vaccinated were recruited, and the dynamics of the BCR repertoire for consecutive vaccinations in two seasons were tracked. In terms of diversity, length, network, V and J gene segments usage, somatic hypermutation (SHM) rate and isotype, it was found that the overall changes were stronger in the acute phase of the first vaccination than the second vaccination. However, the V gene segments of IGHV4-39, IGHV3-9, IGHV3-7 and IGHV1-69 were amplified in the acute phase of the first vaccination, with IGHV3-7 dominant. On the other hand, for the second vaccination, the changes were dominated by IGHV1-69, with potential for coding broad neutralizing antibody. Additional analysis indicates that the application of V gene segment for IGHV3-7 in the acute phase of the first vaccination was due to the elevated usage of isotypes IgM and IgG3. While for IGHV1-69 in the second vaccination, it was contributed by isotypes IgG1 and IgG2. Finally, 41 public BCR clusters were identified in the vaccine group, with both IGHV3-7 and IGHV1-69 were involved and representative complementarity determining region 3 (CDR3) motifs were characterized. This study provides insights into the immune response dynamics following repeated influenza vaccination in humans and can inform universal vaccine design and vaccine strategies in the future.


Assuntos
Cadeias Pesadas de Imunoglobulinas , Influenza Humana , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Influenza Humana/prevenção & controle , Influenza Humana/genética , Regiões Determinantes de Complementaridade/genética , Família Multigênica , Vacinação
9.
Nat Commun ; 14(1): 4079, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37429936

RESUMO

Bats are reservoir hosts for many zoonotic viruses. Despite this, relatively little is known about the diversity and abundance of viruses within individual bats, and hence the frequency of virus co-infection and spillover among them. We characterize the mammal-associated viruses in 149 individual bats sampled from Yunnan province, China, using an unbiased meta-transcriptomics approach. This reveals a high frequency of virus co-infection (simultaneous infection of bat individuals by multiple viral species) and spillover among the animals studied, which may in turn facilitate virus recombination and reassortment. Of note, we identify five viral species that are likely to be pathogenic to humans or livestock, based on phylogenetic relatedness to known pathogens or in vitro receptor binding assays. This includes a novel recombinant SARS-like coronavirus that is closely related to both SARS-CoV and SARS-CoV-2. In vitro assays indicate that this recombinant virus can utilize the human ACE2 receptor such that it is likely to be of increased emergence risk. Our study highlights the common occurrence of co-infection and spillover of bat viruses and their implications for virus emergence.


Assuntos
COVID-19 , Quirópteros , Coinfecção , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Animais , Humanos , Filogenia , SARS-CoV-2 , Viroma , China/epidemiologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética
10.
Cell Rep ; 42(7): 112766, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37421618

RESUMO

Neuraminidase is suggested as an important component for developing a universal influenza vaccine. Targeted induction of neuraminidase-specific broadly protective antibodies by vaccinations is challenging. To overcome this, we rationally select the highly conserved peptides from the consensus amino acid sequence of the globular head domains of neuraminidase. Inspired by the B cell receptor evolution process, a reliable sequential immunization regimen is designed to result in immuno-focusing by steering bulk immune responses to a selected region where broadly protective B lymphocyte epitopes reside. After priming neuraminidase protein-specific antibody responses in C57BL/6 or BALB/c inbred mice strains by immunization or pre-infection, boost immunizations with certain neuraminidase-derived peptide-keyhole limpet hemocyanin conjugates significantly strengthened serum neuraminidase inhibition activities and cross-protections. Overall, this study provides proof of concept for a peptide-based sequential immunization strategy for achieving targeted induction of cross-protective antibody response, which provides references for designing universal vaccines against other highly variable pathogens.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Virus da Influenza A Subtipo H5N1 , Vacinas contra Influenza , Influenza Humana , Infecções por Orthomyxoviridae , Animais , Camundongos , Humanos , Infecções por Orthomyxoviridae/prevenção & controle , Neuraminidase , Anticorpos Antivirais , Camundongos Endogâmicos C57BL , Vacinação , Peptídeos , Camundongos Endogâmicos BALB C , Glicoproteínas de Hemaglutininação de Vírus da Influenza
11.
PLoS Pathog ; 19(6): e1011420, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37262073

RESUMO

Enterovirus A71 (EV-A71) infection is a major cause of severe hand, foot and mouth disease (HFMD) in young children. The characteristics of EV-A71 neutralizing antibodies in HFMD patients are not well understood. In this study, we identified and cloned EV-A71-neutralizing antibodies by single cell RNA and B cell receptor sequencing of peripheral blood mononuclear cells. From 145 plasmablasts, we identified two IgG1 monoclonal antibodies (mAbs) and six IgM mAbs that neutralized EV-A71. Four of the IgM mAbs harbor germline variable sequences and neutralize EV-A71 potently. Two genetically similar IgM antibodies from two patients have recurrent heavy chain variable domain gene usage and similar complementarity-determining region 3 sequences. We mapped the residues of EV-A71 critical for neutralization through selection of virus variants resistant to antibody neutralization in the presence of neutralizing mAbs. The residues critical for neutralization are conserved among EV-A71 genotypes. Epitopes for the two genetically similar antibodies overlap with the SCARB2 binding site of EV-A71. We used escape variants to measure the epitope-specific antibody response in acute phase serum samples from EV-A71 infected HFMD patients. We found that these epitopes are immunogenic and contributed to the neutralizing antibody response against the virus. Our findings advance understanding of antibody response to EV-A71 infection in young children and have translational potential: the IgM mAbs could potentially be used for prevention or treatment of EV-A71 infections.


Assuntos
Enterovirus Humano A , Infecções por Enterovirus , Enterovirus , Doença de Mão, Pé e Boca , Criança , Humanos , Pré-Escolar , Enterovirus/genética , Enterovirus Humano A/genética , Leucócitos Mononucleares , Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos , Imunoglobulina M , Anticorpos Monoclonais , Antígenos Virais/genética
12.
PLoS Pathog ; 19(5): e1011123, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37196033

RESUMO

SARS-CoV Spike (S) protein shares considerable homology with SARS-CoV-2 S, especially in the conserved S2 subunit (S2). S protein mediates coronavirus receptor binding and membrane fusion, and the latter activity can greatly influence coronavirus infection. We observed that SARS-CoV S is less effective in inducing membrane fusion compared with SARS-CoV-2 S. We identify that S813T mutation is sufficient in S2 interfering with the cleavage of SARS-CoV-2 S by TMPRSS2, reducing spike fusogenicity and pseudoparticle entry. Conversely, the mutation of T813S in SARS-CoV S increased fusion ability and viral replication. Our data suggested that residue 813 in the S was critical for the proteolytic activation, and the change from threonine to serine at 813 position might be an evolutionary feature adopted by SARS-2-related viruses. This finding deepened the understanding of Spike fusogenicity and could provide a new perspective for exploring Sarbecovirus' evolution.


Assuntos
COVID-19 , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Humanos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Proteólise , Replicação Viral , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo
14.
Cell Discov ; 8(1): 138, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36575183

RESUMO

N6-deoxyadenosine methylation (6mA) is the most widespread type of DNA modification in prokaryotes and is also abundantly distributed in some unicellular eukaryotes. However, 6mA levels are remarkably low in mammals. The lack of a precise and comprehensive mapping method has hindered more advanced investigations of 6mA. Here, we report a new method MM-seq (modification-induced mismatch sequencing) for genome-wide 6mA mapping based on a novel detection principle. We found that modified DNA bases are prone to form a local open region that allows capture by antibody, for example, via a DNA breathing or base-flipping mechanism. Specified endonuclease or exonuclease can recognize the antibody-stabilized mismatch-like structure and mark the exact modified sites for sequencing readout. Using this method, we examined the genomic positions of 6mA in bacteria (E. coli), green algae (C. reinhardtii), and mammalian cells (HEK239T, Huh7, and HeLa cells). In contrast to bacteria and green algae, human cells possess a very limited number of 6mA sites which are sporadically distributed across the genome of different cell types. After knocking out the RNA m6A methyltransferase METTL3 in mouse ES cells, 6mA becomes mostly diminished. Our results imply that rare 6mA in the mammalian genome is introduced by RNA m6A machinery via a non-targeted mechanism.

15.
bioRxiv ; 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36451889

RESUMO

Bats are reservoir hosts for many zoonotic viruses. Despite this, relatively little is known about the diversity and abundance of viruses within bats at the level of individual animals, and hence the frequency of virus co-infection and inter-species transmission. Using an unbiased meta-transcriptomics approach we characterised the mammalian associated viruses present in 149 individual bats sampled from Yunnan province, China. This revealed a high frequency of virus co-infection and species spillover among the animals studied, with 12 viruses shared among different bat species, which in turn facilitates virus recombination and reassortment. Of note, we identified five viral species that are likely to be pathogenic to humans or livestock, including a novel recombinant SARS-like coronavirus that is closely related to both SARS-CoV-2 and SARS-CoV, with only five amino acid differences between its receptor-binding domain sequence and that of the earliest sequences of SARS-CoV-2. Functional analysis predicts that this recombinant coronavirus can utilize the human ACE2 receptor such that it is likely to be of high zoonotic risk. Our study highlights the common occurrence of inter-species transmission and co-infection of bat viruses, as well as their implications for virus emergence.

16.
Cell Mol Immunol ; 19(11): 1279-1289, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36220993

RESUMO

The rapid mutation and spread of SARS-CoV-2 variants urge the development of effective mucosal vaccines to provide broad-spectrum protection against the initial infection and thereby curb the transmission potential. Here, we designed a chimeric triple-RBD immunogen, 3Ro-NC, harboring one Delta RBD and two Omicron RBDs within a novel protein scaffold. 3Ro-NC elicits potent and broad RBD-specific neutralizing immunity against SARS-CoV-2 variants of concern. Notably, intranasal immunization with 3Ro-NC plus the mucosal adjuvant KFD (3Ro-NC + KFDi.n) elicits coordinated mucosal IgA and higher neutralizing antibody specificity (closer antigenic distance) against the Omicron variant. In Omicron-challenged human ACE2 transgenic mice, 3Ro-NC + KFDi.n immunization significantly reduces the tissue pathology in the lung and lowers the viral RNA copy numbers in both the lung (85.7-fold) and the nasal turbinate (13.6-fold). Nasal virologic control is highly correlated with RBD-specific secretory IgA antibodies. Our data show that 3Ro-NC plus KFD is a promising mucosal vaccine candidate for protection against SARS-CoV-2 Omicron infection, pathology and transmission potential.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Animais , Humanos , Camundongos , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética , Vacinas contra COVID-19/imunologia , Imunidade nas Mucosas , Administração Intranasal
17.
Antiviral Res ; 205: 105383, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35917969

RESUMO

The frequently emerging SARS-CoV-2 variants have weakened the effectiveness of existing COVID-19 vaccines and neutralizing antibody therapy. Nevertheless, the infections of SARS-CoV-2 variants still depend on angiotensin-converting enzyme 2 (ACE2) receptor-mediated cell entry, and thus the soluble human ACE2 (shACE2) is a potential decoy for broadly blocking SARS-CoV-2 variants. In this study, we firstly generated the recombinant AAVrh10-vectored shACE2 constructs, a kind of adeno-associated virus (AAV) serotype with pulmonary tissue tropism, and then validated its inhibition capacity against SARS-CoV-2 infection. To further optimize the minimized ACE2 functional domain candidates, a comprehensive analysis was performed to clarify the interactions between the ACE2 orthologs from various species and the receptor binding domain (RBD) of SARS-CoV-2 spike (S) protein. Based on the key interface amino acids, we designed a series of truncated ACE2 orthologs, and then assessed their potential affinity to bind to SARS-CoV-2 variants RBD in silico. Of note, we found that the 24-83aa fragment of dog ACE2 (dACE224-83) had a higher affinity to the RBD of SARS-CoV-2 variants than that of human ACE2. Importantly, AAVrh10-vectored shACE2 or dACE224-83 constructs exhibited a broadly blockage breadth against SARS-CoV-2 prototype and variants in vitro and ex vivo. Collectively, these data highlighted a promising therapeutic strategy against SARS-CoV-2 variants.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Enzima de Conversão de Angiotensina 2/genética , Animais , COVID-19/terapia , Vacinas contra COVID-19 , Cães , Humanos , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Ligação Proteica , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus , Internalização do Vírus
18.
Emerg Microbes Infect ; 11(1): 2007-2020, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35899581

RESUMO

Dynamic changes of the paired heavy and light chain B cell receptor (BCR) repertoire provide an essential insight into understanding the humoral immune response post-SARS-CoV-2 infection and vaccination. However, differences between the endogenous paired BCR repertoire kinetics in SARS-CoV-2 infection and previously recovered/naïve subjects treated with the inactivated vaccine remain largely unknown. We performed single-cell V(D)J sequencing of B cells from six healthy donors with three shots of inactivated SARS-CoV-2 vaccine (BBIBP-CorV), five people who received the BBIBP-CorV vaccine after having recovered from COVID-19, five unvaccinated COVID-19 recovered patients and then integrated with public data of B cells from four SARS-CoV-2-infected subjects. We discovered that BCR variable (V) genes were more prominently used in the SARS-CoV-2 exposed groups (both in the group with active infection and in the group that had recovered) than in the vaccinated groups. The VH gene that expanded the most after SARS-CoV-2 infection was IGHV3-33, while IGHV3-23 in the vaccinated groups. SARS-CoV-2-infected group enhanced more BCR clonal expansion and somatic hypermutation than the vaccinated healthy group. A small proportion of public clonotypes were shared between the SARS-CoV-2 infected, vaccinated healthy, and recovered groups. Moreover, several public antibodies had been identified against SARS-CoV-2 spike protein. We comprehensively characterize the paired heavy and light chain BCR repertoire from SARS-CoV-2 infection to vaccination, providing further guidance for the development of the next-generation precision vaccine.


Assuntos
COVID-19 , Vacinas Virais , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Receptores de Antígenos de Linfócitos B/genética , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus , Vacinação
19.
J Med Virol ; 94(9): 4193-4205, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35570330

RESUMO

As one of the most rapidly evolving proteins of the genus Betacoronavirus, open reading frames (ORF8's) function and potential pathological consequence in vivo are still obscure. In this study, we show that the secretion of ORF8 is dependent on its N-terminal signal peptide sequence and can be inhibited by reactive oxygen species scavenger and endoplasmic reticulum-Golgi transportation inhibitor in cultured cells. To trace the effect of its possible in vivo secretion, we examined the plasma samples of coronavirus disease 2019 (COVID-19) convalescent patients and found that the patients aged from 40 to 60 had higher antibody titers than those under 40. To explore ORF8's in vivo function, we administered the mice with ORF8 via tail-vein injection to simulate the circulating ORF8 in the patient. Although no apparent difference in body weight, food intake, and vitality was detected between vehicle- and ORF8-treated mice, the latter displayed morphological abnormalities of testes and epididymides, as indicated by the loss of the central ductal lumen accompanied by a decreased fertility in 5-week-old male mice. Furthermore, the analysis of gene expression in the testes between vehicle- and ORF8-treated mice identified a decreased expression of Col1a1, the loss of which is known to be associated with mice's infertility. Although whether our observation in mice could be translated to humans remains unclear, our study provides a potential mouse model that can be used to investigate the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on the human reproductive system.


Assuntos
COVID-19 , Infertilidade Masculina , SARS-CoV-2 , Proteínas Virais , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/sangue , Fertilidade , Humanos , Infertilidade Masculina/virologia , Masculino , Camundongos , Fases de Leitura Aberta
20.
Eur J Psychotraumatol ; 13(1): 2019980, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35111284

RESUMO

Background: As a highly infectious disease with human-to-human transmission characteristics, COVID-19 has caused panic in the general public. Those who have recovered from COVID-19 may experience discrimination and internalized stigma. They may be more likely to worry about social interaction and develop social anxiety. Objectives: This study investigated the associations among hospitalization factors, social/interpersonal factors, personal factors, and social anxiety to reveal the mechanism of social anxiety in COVID-19 survivors. Methods: A cross-sectional, multicenter telephone survey was conducted from July to September 2020 in five Chinese cities (i.e. Wuhan, Nanning, Shenzhen, Zhuhai, and Dongguan); adult COVID-19 survivors were recruited 6 months after they were discharged from the hospital. Linear regressions and path analysis based on the minority stress model were conducted to test the relationships among hospitalization, social/interpersonal factors, personal factors, and social anxiety. Results: The response rate was 74.5% (N = 199, 55.3% females). Linear regression analyses showed that various hospitalization, social/interpersonal, and personal factors were statistically significantly associated with social anxiety. Path analysis showed that the proposed model fit the data well (χ2(df) = 3.196(3), p = .362, CFI = .999, NNFI = .996, RMSEA = .018). Internalized stigma fully mediated the association between perceived discrimination/social support and social anxiety, while it partially mediated the association between perceived affiliate stigma and social anxiety. Conclusions: The results suggest that social/interpersonal and personal factors have a stronger association with social anxiety than hospitalization factors and highlight the importance of internalized stigma in understanding the mechanisms of these relationships. Clinical psychologists can refer to these modifiable psychosocial factors to develop efficient interventions for mental health promotion.


Antecedentes: Como una enfermedad altamente infecciosa con características de transmisión de persona a persona, el COVID-19 ha causado pánico en el público en general. Aquellos que se han recuperado del COVID-19 pueden experimentar discriminación y estigma internalizado. Es más probable que se preocupen por la interacción social y desarrollen ansiedad social.Objetivos: Este estudio investigó las asociaciones entre factores de hospitalización, factores sociales /interpersonales, factores personales y ansiedad social para revelar el mecanismo de ansiedad social en sobrevivientes de COVID-19.Métodos: Se realizó una encuesta telefónica transversal multicentro de julio a septiembre de 2020 en cinco ciudades chinas (es decir, Wuhan, Nanning, Shenzhen, Zhuhai y Dongguan). Se reclutaron sobrevivientes adultos de COVID-19 seis meses después de ser dados de alta del hospital. Se realizaron regresiones lineales y análisis de ruta basados en el modelo de estrés de minoría para probar las relaciones entre la hospitalización, los factores sociales/interpersonales, los factores personales y la ansiedad social.Resultados: La tasa de respuesta fue del 74,5% (N = 199, 55,3% mujeres). Los análisis de regresión lineal mostraron que varios factores de hospitalización, sociales/interpersonales y personales se asociaron de manera estadísticamente significativa con la ansiedad social. El análisis de ruta mostró que el modelo propuesto se ajustaba bien a los datos (χ2 (df) = 3.196 (3), p = .362, CFI = .999, NNFI = .996, RMSEA = .018). El estigma internalizado medió completamente la asociación entre discriminación/apoyo social percibido y ansiedad social, mientras que medió parcialmente la asociación entre el estigma percibido de afiliados y ansiedad social.Conclusiones: Los resultados sugieren que los factores sociales/interpersonales y personales tienen una asociación más fuerte con la ansiedad social que los factores de hospitalización y resaltan la importancia del estigma internalizado en la comprensión de los mecanismos de estas relaciones. Los psicólogos clínicos pueden referirse a estos factores psicosociales modificables para desarrollar intervenciones eficientes para la promoción de la salud mental.


Assuntos
Ansiedade/psicologia , COVID-19/psicologia , Hospitalização , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Estudos Transversais , Medo , Feminino , Seguimentos , Humanos , Masculino , Saúde Mental , Pessoa de Meia-Idade , SARS-CoV-2 , Estigma Social , Apoio Social , Inquéritos e Questionários , Sobreviventes , Adulto Jovem
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