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1.
J Biol Chem ; 299(6): 104767, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37142221

RESUMO

African swine fever, caused by a large icosahedral DNA virus (African swine fever virus, ASFV), is a highly contagious disease in domestic and feral swine, thus posing a significant economic threat to the global swine industry. Currently, there are no effective vaccines or the available methods to control ASFV infection. Attenuated live viruses with deleted virulence factors are considered to be the most promising vaccine candidates; however, the mechanism by which these attenuated viruses confer protection is unclear. Here, we used the Chinese ASFV CN/GS/2018 as a backbone and used homologous recombination to generate a virus in which MGF110-9L and MGF360-9L, two genes antagonize host innate antiviral immune response, were deleted (ASFV-ΔMGF110/360-9L). This genetically modified virus was highly attenuated in pigs and provided effective protection of pigs against parental ASFV challenge. Importantly, we found ASFV-ΔMGF110/360-9L infection induced higher expression of Toll-like receptor 2 (TLR2) mRNA compared with parental ASFV as determined by RNA-Seq and RT-PCR analysis. Further immunoblotting results showed that parental ASFV and ASFV-ΔMGF110/360-9L infection inhibited Pam3CSK4-triggered activating phosphorylation of proinflammatory transcription factor NF-κB subunit p65 and phosphorylation of NF-κB inhibitor IκBα levels, although NF-κB activation was higher in ASFV-ΔMGF110/360-9L-infected cells compared with parental ASFV-infected cells. Additionally, we show overexpression of TLR2 inhibited ASFV replication and the expression of ASFV p72 protein, whereas knockdown of TLR2 had the opposite effect. Our findings suggest that the attenuated virulence of ASFV-ΔMGF110/360-9L might be mediated by increased NF-κB and TLR2 signaling.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Proteínas Virais , Animais , Febre Suína Africana/imunologia , Febre Suína Africana/virologia , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/patogenicidade , Formação de Anticorpos/imunologia , Deleção de Genes , NF-kappa B/genética , Suínos , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/imunologia , Transcriptoma , Proteínas Virais/genética , Proteínas Virais/imunologia , Replicação Viral/imunologia
2.
J Virol ; 97(4): e0005023, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36975794

RESUMO

Antigen epitope identification is a critical step in the vaccine development process and is a momentous cornerstone for the development of safe and efficient epitope vaccines. In particular, vaccine design is difficult when the function of the protein encoded by the pathogen is unknown. The genome of Tilapia lake virus (TiLV), an emerging virus from fish, encodes protein functions that have not been elucidated, resulting in a lag and uncertainty in vaccine development. Here, we propose a feasible strategy for emerging viral disease epitope vaccine development using TiLV. We determined the targets of specific antibodies in serum from a TiLV survivor by panning a Ph.D.-12 phage library, and we identified a mimotope, TYTTRMHITLPI, referred to as Pep3, which provided protection against TiLV after prime-boost vaccination; its immune protection rate was 57.6%. Based on amino acid sequence alignment and structure analysis of the target protein from TiLV, we further identified a protective antigenic site (399TYTTRNEDFLPT410) which is located on TiLV segment 1 (S1). The epitope vaccine with keyhole limpet hemocyanin (KLH-S1399-410) corresponding to the mimotope induced the tilapia to produce a durable and effective antibody response after immunization, and the antibody depletion test confirmed that the specific antibody against S1399-410 was necessary to neutralize TiLV. Surprisingly, the challenge studies in tilapia demonstrated that the epitope vaccine elicited a robust protective response against TiLV challenge, and the survival rate reached 81.8%. In conclusion, this study revealed a concept for screening antigen epitopes of emerging viral diseases, providing promising approaches for development and evaluation of protective epitope vaccines against viral diseases. IMPORTANCE Antigen epitope determination is an important cornerstone for developing efficient vaccines. In this study, we attempted to explore a novel approach for epitope discovery of TiLV, which is a new virus in fish. We investigated the immunogenicity and protective efficacy of all antigenic sites (mimotopes) identified in serum of primary TiLV survivors by using a Ph.D.-12 phage library. We also recognized and identified the natural epitope of TiLV by bioinformatics, evaluated the immunogenicity and protective effect of this antigenic site by immunization, and revealed 2 amino acid residues that play important roles in this epitope. Both Pep3 and S1399-410 (a natural epitope identified by Pep3) elicited antibody titers in tilapia, but S1399-410 was more prominent. Antibody depletion studies showed that anti-S1399-410-specific antibodies were essential for neutralizing TiLV. Our study demonstrated a model for combining experimental and computational screens to identify antigen epitopes, which is attractive for epitope-based vaccine development.


Assuntos
Formação de Anticorpos , Doenças dos Peixes , Infecções por Vírus de RNA , Tilápia , Vacinas Virais , Técnicas de Visualização da Superfície Celular , Simulação por Computador , Epitopos/imunologia , Vacinas Virais/imunologia , Formação de Anticorpos/imunologia , Tilápia/virologia , Linhagem Celular , Vírus de RNA/imunologia , Animais , Anticorpos Antivirais/sangue , Imunidade Humoral/imunologia , Infecções por Vírus de RNA/prevenção & controle , Infecções por Vírus de RNA/veterinária , Infecções por Vírus de RNA/virologia , Doenças dos Peixes/prevenção & controle , Doenças dos Peixes/virologia
3.
PLoS One ; 18(2): e0276829, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36757919

RESUMO

Antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) target multiple epitopes on different domains of the spike protein, and other SARS-CoV-2 proteins. We developed a SARS-CoV-2 multi-antigen protein microarray with the nucleocapsid, spike and its domains (S1, S2), and variants with single (D614G, E484K, N501Y) or double substitutions (N501Y/Deletion69/70), allowing a more detailed high-throughput analysis of the antibody repertoire following infection. The assay was demonstrated to be reliable and comparable to ELISA. We analyzed antibodies from 18 COVID-19 patients and 12 recovered convalescent donors. The S IgG level was higher than N IgG in most of the COVID-19 patients, and the receptor-binding domain of S1 showed high reactivity, but no antibodies were detected against the heptad repeat domain 2 of S2. Furthermore, antibodies were detected against S variants with single and double substitutions in COVID-19 patients who were infected with SARS-CoV-2 early in the pandemic. Here we demonstrated that the SARS-CoV-2 multi-antigen protein microarray is a powerful tool for detailed characterization of antibody responses, with potential utility in understanding the disease progress and assessing current vaccines and therapies against evolving SARS-CoV-2.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/genética , Anticorpos Antivirais/imunologia , Formação de Anticorpos/genética , Formação de Anticorpos/imunologia , COVID-19/genética , COVID-19/imunologia , COVID-19/virologia , Imunoglobulina G , Análise Serial de Proteínas , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus
5.
J Infect Dis ; 227(2): 193-201, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35514141

RESUMO

Understanding the duration of antibodies to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus that causes COVID-19 is important to controlling the current pandemic. Participants from the Texas Coronavirus Antibody Response Survey (Texas CARES) with at least 1 nucleocapsid protein antibody test were selected for a longitudinal analysis of antibody duration. A linear mixed model was fit to data from participants (n = 4553) with 1 to 3 antibody tests over 11 months (1 October 2020 to 16 September 2021), and models fit showed that expected antibody response after COVID-19 infection robustly increases for 100 days postinfection, and predicts individuals may remain antibody positive from natural infection beyond 500 days depending on age, body mass index, smoking or vaping use, and disease severity (hospitalized or not; symptomatic or not).


Assuntos
Anticorpos Antivirais , COVID-19 , SARS-CoV-2 , Humanos , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , COVID-19/epidemiologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus , Texas/epidemiologia , Fatores de Tempo
6.
J Virol ; 96(13): e0038322, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35699445

RESUMO

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


Assuntos
Formação de Anticorpos , Vacinas contra COVID-19 , COVID-19 , Nanopartículas , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Formação de Anticorpos/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Humanos , Camundongos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
7.
Cell Rep ; 39(2): 110680, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35395191

RESUMO

Knowledge about the impact of prior severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection of the elderly on mRNA vaccination response is needed to appropriately address the demand for additional vaccinations in this vulnerable population. Here, we show that octogenarians, a high-risk population, mount a sustained SARS-CoV-2 spike-specific immunoglobulin G (IgG) antibody response for 15 months following infection. This response boosts antibody levels 35-fold upon receiving a single dose of BNT162b2 mRNA vaccine 15 months after recovery from coronavirus disease 2019 (COVID-19). In contrast, antibody responses in naive individuals boost only 6-fold after a second vaccine. Spike-specific angiotensin-converting enzyme 2 (ACE2) antibody binding responses in the previously infected octogenarians following two vaccine doses exceed those found in a naive cohort after two doses. RNA sequencing (RNA-seq) demonstrates activation of interferon-induced genetic programs, which persist only in the previously infected. A preferential increase of specific immunoglobulin G heavy chain variable (IGHV) clonal transcripts that are the basis of neutralizing antibodies is observed only in the previously infected nuns.


Assuntos
Formação de Anticorpos , COVID-19 , SARS-CoV-2 , Vacinas de mRNA , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Vacina BNT162 , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Humanos , Imunoglobulina G , Octogenários , RNA Mensageiro/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus , Vacinação , Vacinas Sintéticas , Vacinas de mRNA/uso terapêutico
8.
PLoS One ; 17(3): e0265130, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35271655

RESUMO

BACKGROUND AND OBJECTIVES: Kidney transplant recipients are highly vulnerable to the serious complications of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infections and thus stand to benefit from vaccination. Therefore, it is necessary to establish the effectiveness of available vaccines as this group of patients was not represented in the randomized trials. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A total of 707 consecutive adult kidney transplant recipients in a single center in the United Kingdom were evaluated. 373 were confirmed to have received two doses of either the BNT162b2 (Pfizer-BioNTech) or AZD1222 (Oxford-AstraZeneca) and subsequently had SARS-COV-2 antibody testing were included in the final analysis. Participants were excluded from the analysis if they had a previous history of SARS-COV-2 infection or were seropositive for SARS-COV-2 antibody pre-vaccination. Multivariate and propensity score analyses were performed to identify the predictors of antibody response to SARS-COV-2 vaccines. The primary outcome was seroconversion rates following two vaccine doses. RESULTS: Antibody responders were 56.8% (212/373) and non-responders 43.2% (161/373). Antibody response was associated with greater estimated glomerular filtration (eGFR) rate [odds ratio (OR), for every 10 ml/min/1.73m2 = 1.40 (1.19-1.66), P<0.001] whereas, non-response was associated with mycophenolic acid immunosuppression [OR, 0.02(0.01-0.11), p<0.001] and increasing age [OR per 10year increase, 0.61(0.48-0.78), p<0.001]. In the propensity-score analysis of four treatment variables (vaccine type, mycophenolic acid, corticosteroid, and triple immunosuppression), only mycophenolic acid was significantly associated with vaccine response [adjusted OR by PSA 0.17 (0.07-0.41): p<0.001]. 22 SARS-COV-2 infections were recorded in our cohort following vaccination. 17(77%) infections, with 3 deaths, occurred in the non-responder group. No death occurred in the responder group. CONCLUSION: Vaccine response in allograft recipients after two doses of SARS-COV-2 vaccine is poor compared to the general population. Maintenance with mycophenolic acid appears to have the strongest negative impact on vaccine response.


Assuntos
Formação de Anticorpos/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Adulto , Idoso , Anticorpos Antivirais/imunologia , Estudos de Coortes , Feminino , Humanos , Terapia de Imunossupressão , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Nefrologia , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Transplantados/estatística & dados numéricos , Reino Unido , Vacinação
9.
Front Immunol ; 13: 828053, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35251012

RESUMO

Recent increases in SARS-CoV-2 infections have led to questions about duration and quality of vaccine-induced immune protection. While numerous studies have been published on immune responses triggered by vaccination, these often focus on studying the impact of one or two immunisation schemes within subpopulations such as immunocompromised individuals or healthcare workers. To provide information on the duration and quality of vaccine-induced immune responses against SARS-CoV-2, we analyzed antibody titres against various SARS-CoV-2 antigens and ACE2 binding inhibition against SARS-CoV-2 wild-type and variants of concern in samples from a large German population-based seroprevalence study (MuSPAD) who had received all currently available immunisation schemes. We found that homologous mRNA-based or heterologous prime-boost vaccination produced significantly higher antibody responses than vector-based homologous vaccination. Ad26.CoV2S.2 performance was particularly concerning with reduced titres and 91.7% of samples classified as non-responsive for ACE2 binding inhibition, suggesting that recipients require a booster mRNA vaccination. While mRNA vaccination induced a higher ratio of RBD- and S1-targeting antibodies, vector-based vaccines resulted in an increased proportion of S2-targeting antibodies. Given the role of RBD- and S1-specific antibodies in neutralizing SARS-CoV-2, their relative over-representation after mRNA vaccination may explain why these vaccines have increased efficacy compared to vector-based formulations. Previously infected individuals had a robust immune response once vaccinated, regardless of which vaccine they received, which could aid future dose allocation should shortages arise for certain manufacturers. Overall, both titres and ACE2 binding inhibition peaked approximately 28 days post-second vaccination and then decreased.


Assuntos
Ad26COVS1/imunologia , COVID-19/imunologia , Imunidade Humoral/imunologia , SARS-CoV-2/crescimento & desenvolvimento , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Estudos Transversais , Alemanha , Humanos , Estudos Soroepidemiológicos , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação/métodos
10.
Front Immunol ; 13: 827889, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35251011

RESUMO

It is well established that pregnancy induces deep changes in the immune system. This is part of the physiological adaptation of the female organism to the pregnancy and the immunological tolerance toward the fetus. Indeed, over the three trimesters, the suppressive T regulatory lymphocytes are progressively more represented, while the expression of co-stimulatory molecules decreases overtime. Such adaptations relate to an increased risk of infections and progression to severe disease in pregnant women, potentially resulting in an altered generation of long-lived specific immunological memory of infection contracted during pregnancy. How potent is the immune response against SARS-CoV-2 in infected pregnant women and how long the specific SARS-CoV-2 immunity might last need to be urgently addressed, especially considering the current vaccinal campaign. To address these questions, we analyzed the long-term immunological response upon SARS-CoV-2 infection in pregnant women from delivery to a six-months follow-up. In particular, we investigated the specific antibody production, T cell memory subsets, and inflammation profile. Results show that 80% developed an anti-SARS-CoV-2-specific IgG response, comparable with the general population. While IgG were present only in 50% of the asymptomatic subjects, the antibody production was elicited by infection in all the mild-to-critical patients. The specific T-cell memory subsets rebalanced over-time, and the pro-inflammatory profile triggered by specific SARS-CoV-2 stimulation faded away. These results shed light on SARS-CoV-2-specific immunity in pregnant women; understanding the immunological dynamics of the immune system in response to SARS-CoV-2 is essential for defining proper obstetric management of pregnant women and fine tune gender-specific vaccinal plans.


Assuntos
COVID-19/imunologia , Memória Imunológica/imunologia , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/virologia , SARS-CoV-2/imunologia , Adulto , Animais , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Linfócitos B/imunologia , Linhagem Celular , Chlorocebus aethiops , Feminino , Humanos , Gravidez , Gestantes , Estudos Prospectivos , Glicoproteína da Espícula de Coronavírus/imunologia , Células Vero , Adulto Jovem
11.
PLoS Pathog ; 18(2): e1010248, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35134084

RESUMO

Many SARS-CoV-2 variants have mutations at key sites targeted by antibodies. However, it is unknown if antibodies elicited by infection with these variants target the same or different regions of the viral spike as antibodies elicited by earlier viral isolates. Here we compare the specificities of polyclonal antibodies produced by humans infected with early 2020 isolates versus the B.1.351 variant of concern (also known as Beta or 20H/501Y.V2), which contains mutations in multiple key spike epitopes. The serum neutralizing activity of antibodies elicited by infection with both early 2020 viruses and B.1.351 is heavily focused on the spike receptor-binding domain (RBD). However, within the RBD, B.1.351-elicited antibodies are more focused on the "class 3" epitope spanning sites 443 to 452, and neutralization by these antibodies is notably less affected by mutations at residue 484. Our results show that SARS-CoV-2 variants can elicit polyclonal antibodies with different immunodominance hierarchies.


Assuntos
Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Anticorpos Neutralizantes/imunologia , Epitopos/imunologia , Humanos , Imunização Passiva/métodos , Testes de Neutralização , SARS-CoV-2/genética , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Tratamento Farmacológico da COVID-19
12.
Front Immunol ; 13: 811952, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35126396

RESUMO

Numerous studies have suggested that the titers of antibodies against SARS-CoV-2 are associated with the COVID-19 severity, however, the types of antibodies associated with the disease maximum severity and the timing at which the associations are best observed, especially within one week after symptom onset, remain controversial. We attempted to elucidate the antibody responses against SARS-CoV-2 that are associated with the maximum severity of COVID-19 in the early phase of the disease, and to investigate whether antibody testing might contribute to prediction of the disease maximum severity in COVID-19 patients. We classified the patients into four groups according to the disease maximum severity (severity group 1 (did not require oxygen supplementation), severity group 2a (required oxygen supplementation at low flow rates), severity group 2b (required oxygen supplementation at relatively high flow rates), and severity group 3 (required mechanical ventilatory support)), and serially measured the titers of IgM, IgG, and IgA against the nucleocapsid protein, spike protein, and receptor-binding domain of SARS-CoV-2 until day 12 after symptom onset. The titers of all the measured antibody responses were higher in severity group 2b and 3, especially severity group 2b, as early as at one week after symptom onset. Addition of data obtained from antibody testing improved the ability of analysis models constructed using a machine learning technique to distinguish severity group 2b and 3 from severity group 1 and 2a. These models constructed with non-vaccinated COVID-19 patients could not be applied to the cases of breakthrough infections. These results suggest that antibody testing might help physicians identify non-vaccinated COVID-19 patients who are likely to require admission to an intensive care unit.


Assuntos
Anticorpos Antivirais/sangue , Vacinas contra COVID-19/sangue , COVID-19/sangue , SARS-CoV-2/imunologia , Índice de Gravidade de Doença , Hesitação Vacinal , Formação de Anticorpos/imunologia , COVID-19/imunologia , COVID-19/patologia , Vacinas contra COVID-19/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Aprendizado de Máquina , Domínios Proteicos/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Fatores de Tempo , Vacinação
13.
Front Immunol ; 13: 811020, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35126395

RESUMO

BACKGROUND: Heterologous vaccinations against SARS-CoV-2 with ChAdOx1 nCoV-19 and a second dose of an mRNA-based vaccine have been shown to be more immunogenic than homologous ChAdOx1 nCoV-19. In the current study, we examined the kinetics of the antibody response to the second dose of three different vaccination regimens (homologous ChAdOx1 nCoV-19 vs. ChAdOx1 nCoV-19 + BNT162b2 or mRNA-1273) against SARS-CoV-2 in a longitudinal manner; whether there are differences in latency or amplitude of the early response and which markers are most suitable to detect these responses. METHODS: We performed assays for anti-S1 IgG and IgA, anti-NCP IgG and a surrogate neutralization assay on serum samples collected from 57 participants on the day of the second vaccination as well as the following seven days. RESULTS: All examined vaccination regimens induced detectable antibody responses within the examined time frame. Both heterologous regimens induced responses earlier and with a higher amplitude than homologous ChAdOx1 nCoV-19. Between the heterologous regimens, amplitudes were somewhat higher for ChAdOx1 nCoV-19 + mRNA-1273. There was no difference in latency between the IgG and IgA responses. Increases in the surrogate neutralization assay were the first changes to be detectable for all regimens and the only significant change seen for homologous ChAdOx1 nCoV-19. DISCUSSION: Both examined heterologous vaccination regimens are superior in immunogenicity, including the latency of the response, to homologous ChAdOx1 nCoV-19. While the IgA response has a shorter latency than the IgG response after the first dose, no such difference was found after the second dose, implying that both responses are driven by separate plasma cell populations. Early and steep increases in surrogate neutralization levels suggest that this might be a more sensitive marker for antibody responses after vaccination against SARS-CoV-2 than absolute levels of anti-S1 IgG.


Assuntos
Vacina de mRNA-1273 contra 2019-nCoV/imunologia , Anticorpos Neutralizantes/sangue , Vacina BNT162/imunologia , ChAdOx1 nCoV-19/imunologia , Imunização Secundária/métodos , SARS-CoV-2/imunologia , Adulto , Fatores Etários , Anticorpos Antivirais/sangue , Formação de Anticorpos/imunologia , COVID-19/imunologia , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T/imunologia , Vacinação , Adulto Jovem
14.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35177472

RESUMO

While influenza infection induces robust, long-lasting, antibody responses and protection, including the T follicular helper cells (TFH) required to drive B cell germinal center (GC) responses, most influenza vaccines do not. We investigated the mechanisms that drive strong TFH responses during infection. Infection induces viral replication and antigen (Ag) presentation lasting through the CD4 effector phase, but Ag and pathogen recognition receptor signals are short-lived after vaccination. We analyzed the need for both infection and Ag presentation at the effector phase, using an in vivo sequential transfer model to time their availability. Differentiation of CD4 effectors into TFH and GC-TFH required that they recognize Ag locally in the site of TFH development, at the effector phase, but did not depend on specific Ag-presenting cells (APCs). In addition, concurrent signals from infection were necessary even when sufficient Ag was presented. Providing these signals with a second dose of live attenuated influenza vaccine at the effector phase drove TFH and GC-TFH development equivalent to live infection. The results suggest that vaccine approaches can induce strong TFH development that supports GC responses akin to infection, if they supply these effector phase signals at the right time and site. We suggest that these requirements create a checkpoint that ensures TFH only develop fully when infection is still ongoing, thereby avoiding unnecessary, potentially autoimmune, responses.


Assuntos
Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Células T Auxiliares Foliculares/imunologia , Animais , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Antígenos , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Feminino , Centro Germinativo/imunologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Células T Auxiliares Foliculares/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Vacinas Atenuadas/imunologia
15.
Cell Rep ; 38(7): 110388, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35172138

RESUMO

Powassan virus (POWV) is a tick-borne pathogen for which humans are an incidental host. POWV infection can be fatal or result in long-term neurological sequelae; however, there are no approved vaccinations for POWV. Integral to efficacious vaccine development is the identification of correlates of protection, which we accomplished in this study by utilizing a murine model of POWV infection. Using POWV lethal and sub-lethal challenge models, we show that (1) robust B and T cell responses are necessary for immune protection, (2) POWV lethality can be attributed to both viral- and host-mediated drivers of disease, and (3) knowledge of the immune correlates of protection against POWV can be applied in a virus-like particle (VLP)-based vaccination approach that provides protection from lethal POWV challenge. Identification of these immune protection factors is significant as it will aid in the rational design of POWV vaccines.


Assuntos
Linfócitos B/imunologia , Vírus da Encefalite Transmitidos por Carrapatos/imunologia , Encefalite Transmitida por Carrapatos/imunologia , Encefalite Transmitida por Carrapatos/prevenção & controle , Linfócitos T/imunologia , Vacinação , Vírion/imunologia , Animais , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Especificidade de Anticorpos/imunologia , Modelos Animais de Doenças , Encefalite Transmitida por Carrapatos/virologia , Interações Hospedeiro-Patógeno/imunologia , Camundongos Endogâmicos C57BL
16.
Nat Commun ; 13(1): 907, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35173150

RESUMO

Population antibody surveillance helps track immune responses to COVID-19 vaccinations at scale, and identify host factors that may affect antibody production. We analyse data from 212,102 vaccinated individuals within the REACT-2 programme in England, which uses self-administered lateral flow antibody tests in sequential cross-sectional community samples; 71,923 (33.9%) received at least one dose of BNT162b2 vaccine and 139,067 (65.6%) received ChAdOx1. For both vaccines, antibody positivity peaks 4-5 weeks after first dose and then declines. At least 21 days after second dose of BNT162b2, close to 100% of respondents test positive, while for ChAdOx1, this is significantly reduced, particularly in the oldest age groups (72.7% [70.9-74.4] at ages 75 years and above). For both vaccines, antibody positivity decreases with age, and is higher in females and those with previous infection. Antibody positivity is lower in transplant recipients, obese individuals, smokers and those with specific comorbidities. These groups will benefit from additional vaccine doses.


Assuntos
Envelhecimento/imunologia , Anticorpos Antivirais/sangue , Vacina BNT162/imunologia , ChAdOx1 nCoV-19/imunologia , SARS-CoV-2/imunologia , Fatores Etários , Idoso , Formação de Anticorpos/imunologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos Transversais , Inglaterra/epidemiologia , Feminino , Humanos , Programas de Imunização , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores Sexuais , Vacinação
17.
Front Immunol ; 13: 827306, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35173736

RESUMO

Background: Effective vaccines against coronavirus disease 2019 (COVID-19) are available worldwide; however, the longevity of vaccine effectiveness is not known. Objective: We performed a prospective observational study to assess the antibody response of healthcare workers against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) after BNT162b2 mRNA COVID-19 vaccination. Methods: SARS-CoV-2 neutralizing antibody (nAb) and spike (S) protein-IgG (S-IgG) antibody titers were examined in participants who received two doses of the BNT162b2 mRNA COVID-19 vaccine in a single center between March 1, 2021, and October 11, 2021. Antibody levels were analyzed at four times: before vaccination (visit 1), 4 weeks after the first vaccination (visit 2), 3 months after the second vaccination (visit 3), and 6 months after the second vaccination (visit 4). Results: A total of 249 healthcare workers at Jeju National University Hospital were enrolled in this study, and 982 blood samples were analyzed. The mean age was 38.1 ± 9.5 years, and 145 (58.2%) participants were females. Positive nAbs (inhibition rates ≥ 20%) were measured in 166/249 (66.7%) subjects at visit 2, 237/243 (97.5%) subjects at visit 3, and 150/237 (63.3%) subjects at visit 4. A S-IgG (≥50 AU/mL) positivity was detected in 246/249 (98.8%) subjects at visit 1, and all participants had positive S-IgG antibody levels at visits 3 and 4 after being fully vaccinated. Further analysis of S-IgG levels revealed a median quantitative antibody level of 1275.1 AU/mL (interquartile range [IQR] 755.5-2119.0) at visit 2, 2765.9 AU/mL (IQR 1809.8-4138.4) at visit 3, and 970.1 AU/mL (IQR 606.0-1495.9) at visit 4. Patient characteristics, such as age, body mass index, and comorbidity, had no relationship with nAb or S-IgG levels at any of the visits. Considering the change in antibody levels over time, both nAb and S-IgG levels at visit 4 decreased compared with the corresponding levels at visit 3. No evidence of SARS-CoV-2 infection was found among any of the participants throughout the study. Conclusions: The BNT162b2 mRNA vaccine was effective in protecting healthcare personnel working in COVID-19-related departments. While the level of S-IgG antibodies was maintained for 6 months after the second vaccination, nAb levels waned over this 6-month period, indicating the need for a booster vaccination in some healthcare workers 6 months after full vaccination. Herein, we suggest that further studies are needed to evaluate the need for an interval of booster vaccination after full vaccination.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Vacina BNT162/imunologia , SARS-CoV-2/imunologia , Eficácia de Vacinas/estatística & dados numéricos , Adulto , Idoso , Formação de Anticorpos/imunologia , COVID-19/prevenção & controle , Feminino , Pessoal de Saúde/estatística & dados numéricos , Humanos , Imunização Secundária , Imunoglobulina G/sangue , Testes Imunológicos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , República da Coreia , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto Jovem
18.
Int J Mol Sci ; 23(3)2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35163254

RESUMO

Human endogenous retroviruses (HERVs) are remnants of ancient retroviral infections that have become fixed in the human genome. While HERV genes are typically silenced in healthy somatic cells, there are numerous reports of HERV transcription and translation across a wide spectrum of cancers, while T and B cell responses against HERV proteins have been detected in cancer patients. This review systematically categorizes the published evidence on the expression of and adaptive immune response against specific HERVs in distinct cancer types. A systematic literature search was performed using Medical Search Headings (MeSH) in the PubMed/Medline database. Papers were included if they described the translational activity of HERVs. We present multiple tables that pair the protein expression of specific HERVs and cancer types with information on the quality of the evidence. We find that HERV-K is the most investigated HERV. HERV-W (syncytin-1) is the second-most investigated, while other HERVs have received less attention. From a therapeutic perspective, HERV-K and HERV-E are the only HERVs with experimental demonstration of effective targeted therapies, but unspecific approaches using antiviral and demethylating agents in combination with chemo- and immunotherapies have also been investigated.


Assuntos
Formação de Anticorpos/imunologia , Retrovirus Endógenos/imunologia , Neoplasias/imunologia , Neoplasias/terapia , Infecções por Retroviridae/imunologia , Proteínas Virais/imunologia , Animais , Interações Hospedeiro-Patógeno/imunologia , Humanos
19.
Diabetes Metab Syndr ; 16(2): 102406, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35104750

RESUMO

BACKGROUND AND AIM: DM patients' antibody response after the COVID-19 vaccine is still unknown amid the COVID-19 vaccination rollout. This study aimed to explore the SARS-CoV-2 antibody response or seropositivity among DM patients following the COVID-19 vaccine administration. METHODS: We performed a systematic review of the literature consisting of observational or cross-sectional studies, which reported the antibody serology or seropositivity among DM patients by following the PRISMA 2020 guidelines. RESULTS: Eight studies with a total of 64468 patients were identified, and 5156 (7.9%) of them had diabetes. Most studies showed that antibody response and seropositivity in DM patients were lower than healthy population after one until four weeks following full COVID-19 vaccination dose. CONCLUSION: The antibody response and seropositivity after the COVID-19 vaccine in DM patients were lower than in healthy subjects. Therefore, DM patients are expected to receive vaccines according to the dose and schedule appropriately and might be prioritized to receive vaccine boosters.


Assuntos
Formação de Anticorpos/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Diabetes Mellitus Tipo 2/imunologia , SARS-CoV-2/imunologia , Anticorpos Antivirais/sangue , Vacina BNT162/imunologia , COVID-19/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Vacinação
20.
J Clin Invest ; 132(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34981778

RESUMO

We investigated the interplay between genetics and oral peanut protein exposure in the determination of the immunological response to peanut using the targeted intervention in the LEAP clinical trial. We identified an association between peanut-specific IgG4 and HLA-DQA1*01:02 that was only observed in the presence of sustained oral peanut protein exposure. The association between IgG4 and HLA-DQA1*01:02 was driven by IgG4 specific for the Ara h 2 component. Once peanut consumption ceased, the association between IgG4-specific Ara h 2 and HLA-DQA1*01:02 was attenuated. The association was validated by observing expanded IgG4-specific epitopes in people who carried HLA-DQA1*01:02. Notably, we confirmed the previously reported associations with HLA-DQA1*01:02 and peanut allergy risk in the absence of oral peanut protein exposure. Interaction between HLA and presence or absence of exposure to peanut in an allergen- and epitope-specific manner implicates a mechanism of antigen recognition that is fundamental to driving immune responses related to allergy risk or protection.


Assuntos
Albuminas 2S de Plantas/imunologia , Alelos , Formação de Anticorpos , Antígenos de Plantas/imunologia , Arachis , Cadeias alfa de HLA-DQ , Imunoglobulina G/imunologia , Hipersensibilidade a Amendoim , Formação de Anticorpos/genética , Formação de Anticorpos/imunologia , Criança , Feminino , Cadeias alfa de HLA-DQ/genética , Cadeias alfa de HLA-DQ/imunologia , Humanos , Masculino , Hipersensibilidade a Amendoim/genética , Hipersensibilidade a Amendoim/imunologia
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