RESUMO
La mayoría de las complicaciones y fallecimientos relacionados con la gripe estacional ocurren en población de 65 años o más y con enfermedades de base, y la vacuna frente a la gripe es la forma más efectiva de prevenirlas. La inmunización es menos eficaz en los adultos mayores debido a la inmunosenescencia. Las vacunas adyuvadas con MF59, diseñadas para mejorar la magnitud, persistencia y amplitud de la respuesta inmunitaria en personas de 65 años o más, se vienen utilizando en la práctica clínica desde 1997 en su formulación trivalente y, desde 2020, en formulación tetravalente. Los datos de diversos estudios muestran que estas vacunas son seguras para todos los grupos de edad, con un perfil de reactogenicidad similar al de la vacuna convencional, y que resultan especialmente efectivas para potenciar la respuesta inmunitaria en la población de 65 años o más, al aumentar los títulos de anticuerpos tras la vacunación y reducir significativamente el riesgo de ingreso hospitalario. Las vacunas adyuvadas han demostrado otorgar protección cruzada frente a cepas heterólogas y ser igual de efectivas que la vacuna de alta dosis en población de 65 años o más. En esta revisión se analiza la evidencia científica sobre la eficacia y la efectividad de la vacuna adyuvada con MF59 en la práctica clínica real en personas ≥65 años mediante una revisión narrativa y descriptiva de los datos publicados en ensayos clínicos, estudios observacionales y revisiones sistemáticas o metaanálisis (AU)
Most of the complications and deaths related to seasonal flu occur in the elderly population (≥65 years) with comorbidities, and the influenza vaccine is the most effective way to prevent them. Immunization is less effective in older adults due to immunosenescence. MF59-adjuvanted vaccines, designed to improve the magnitude, persistence and amplitude of the immune response in elderly people, have been used in clinical practice since 1997 in their trivalent formulation and, since 2020, in their tetravalent formulation. Data from various studies show that these vaccines are not only safe for all age groups, with a reactogenicity profile similar to that of the conventional vaccine, but also that they are especially effective in boosting the immune response in the population aged 65 or over by increasing antibody titers after vaccination and significantly reducing the risk of hospital admission. Adjuvanted vaccines have been shown to provide cross-protection against heterologous strains and to be as effective as the high-dose vaccine in the population aged 65 or over. In this review, the scientific evidence on the efficacy and effectiveness of the MF59-adjuvanted vaccine in real clinical practice in people ≥65 years of age is analyzed through a narrative and descriptive review of the literature with data from clinical trials, observational studies and systematic reviews or meta-analysis (AU)
Assuntos
Humanos , Idoso , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Avaliação de Eficácia-Efetividade de Intervenções , Anticorpos Antivirais/imunologia , Adjuvantes ImunológicosRESUMO
BACKGROUND: Population screening of asymptomatic persons with Epstein-Barr virus (EBV) DNA or antibodies has improved the diagnosis of nasopharyngeal carcinoma and survival among affected persons. However, the positive predictive value of current screening strategies is unsatisfactory even in areas where nasopharyngeal carcinoma is endemic. METHODS: We designed a peptide library representing highly ranked B-cell epitopes of EBV coding sequences to identify novel serologic biomarkers for nasopharyngeal carcinoma. After a retrospective case-control study, the performance of the novel biomarker anti-BNLF2b total antibody (P85-Ab) was validated through a large-scale prospective screening program and compared with that of the standard two-antibody-based screening method (EBV nuclear antigen 1 [EBNA1]-IgA and EBV-specific viral capsid antigen [VCA]-IgA). RESULTS: P85-Ab was the most promising biomarker for nasopharyngeal carcinoma screening, with high sensitivity (94.4%; 95% confidence interval [CI], 86.4 to 97.8) and specificity (99.6%; 95% CI, 97.8 to 99.9) in the retrospective case-control study. Among the 24,852 eligible participants in the prospective cohort, 47 cases of nasopharyngeal carcinoma (38 at an early stage) were identified. P85-Ab showed higher sensitivity than the two-antibody method (97.9% vs. 72.3%; ratio, 1.4 [95% CI, 1.1 to 1.6]), higher specificity (98.3% vs. 97.0%; ratio, 1.01 [95% CI, 1.01 to 1.02]), and a higher positive predictive value (10.0% vs. 4.3%; ratio, 2.3 [95% CI, 1.8 to 2.8]). The combination of P85-Ab and the two-antibody method markedly increased the positive predictive value to 44.6% (95% CI, 33.8 to 55.9), with sensitivity of 70.2% (95% CI, 56.0 to 81.4). CONCLUSIONS: Our results suggest that P85-Ab is a promising novel biomarker for nasopharyngeal carcinoma screening, with higher sensitivity, specificity, and positive predictive value than the standard two-antibody method. (Funded by the National Key Research and Development Program of China and others; ClinicalTrials.gov number, NCT04085900.).
Assuntos
Anticorpos Antivirais , Detecção Precoce de Câncer , Herpesvirus Humano 4 , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Proteínas Virais , Humanos , Anticorpos Antivirais/imunologia , Estudos de Casos e Controles , Herpesvirus Humano 4/imunologia , Imunoglobulina A , Programas de Rastreamento , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/imunologia , Carcinoma Nasofaríngeo/virologia , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/imunologia , Neoplasias Nasofaríngeas/virologia , Estudos Prospectivos , Estudos Retrospectivos , Biomarcadores/análise , Proteínas Virais/imunologia , Epitopos/imunologiaRESUMO
The Omicron lineage of SARS-CoV-2, which was first reported in November 2021, has spread globally and become dominant, splitting into several sublineages. Experiments have shown that Omicron lineage has escaped or reduced the activity of existing monoclonal antibodies, but the origin of escape mechanism caused by mutation is still unknown. This work uses molecular dynamics and umbrella sampling methods to reveal the escape mechanism of BA.1.1 to monoclonal antibody (mAb) Tixagevimab (AZD1061) and BA.5 to mAb Cilgavimab (AZD8895), both mAbs were combined to form antibody cocktail, Evusheld (AZD7442). The binding free energy of BA.1.1-AZD1061 and BA.5-AZD8895 has been severely reduced due to multiple-site mutated Omicron variants. Our results show that the two Omicron variants, which introduce a substantial number of positively charged residues, can weaken the electrostatic attraction between the receptor binding domain (RBD) and AZD7442, thus leading to a decrease in affinity. Additionally, using umbrella sampling along dissociation pathway, we found that the two Omicron variants severely impaired the interaction between the RBD of SARS-CoV-2's spike glycoprotein (S protein) and complementary determining regions (CDRs) of mAbs, especially in CDR3H. Although mAbs AZD8895 and AZD1061 are knocked out by BA.5 and BA.1.1, respectively, our results confirm that the antibody cocktail AZD7442 retains activity against BA.1.1 and BA.5 because another antibody is still on guard. The study provides theoretical insights for mAbs interacting with BA.1.1 and BA.5 from both energetic and dynamic perspectives, and we hope this will help in developing new monoclonals and combinations to protect those unable to mount adequate vaccine responses.
Assuntos
COVID-19 , Evasão da Resposta Imune , COVID-19/imunologia , Simulação por Computador , Humanos , Anticorpos Antivirais/química , Anticorpos Antivirais/imunologia , Modelos Moleculares , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Ligação de HidrogênioRESUMO
Pronounced immune escape by the SARS-CoV-2 Omicron variant has resulted in many individuals possessing hybrid immunity, generated through a combination of vaccination and infection. Concerns have been raised that omicron breakthrough infections in triple-vaccinated individuals result in poor induction of omicron-specific immunity, and that prior SARS-CoV-2 infection is associated with immune dampening. Taking a broad and comprehensive approach, we characterize mucosal and blood immunity to spike and non-spike antigens following BA.1/BA.2 infections in triple mRNA-vaccinated individuals, with and without prior SARS-CoV-2 infection. We find that most individuals increase BA.1/BA.2/BA.5-specific neutralizing antibodies following infection, but confirm that the magnitude of increase and post-omicron titres are higher in the infection-naive. In contrast, significant increases in nasal responses, including neutralizing activity against BA.5 spike, are seen regardless of infection history. Spike-specific T cells increase only in infection-naive vaccinees; however, post-omicron T cell responses are significantly higher in the previously-infected, who display a maximally induced response with a highly cytotoxic CD8+ phenotype following their 3rd mRNA vaccine dose. Responses to non-spike antigens increase significantly regardless of prior infection status. These findings suggest that hybrid immunity induced by omicron breakthrough infections is characterized by significant immune enhancement that can help protect against future omicron variants.
Assuntos
Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Humanos , COVID-19/imunologia , COVID-19/virologia , SARS-CoV-2/classificação , Vacinas contra COVID-19/administração & dosagem , Imunidade , Anticorpos Antivirais/imunologia , Anticorpos Neutralizantes , Imunoglobulina A , Linfócitos T/imunologia , Imunidade nas Mucosas , Masculino , Feminino , AdultoRESUMO
Understanding protective immunity to COVID-19 facilitates preparedness for future pandemics and combats new SARS-CoV-2 variants emerging in the human population. Neutralizing antibodies have been widely studied; however, on the basis of large-scale exome sequencing of protected versus severely ill patients with COVID-19, local cell-autonomous defence is also crucial1-4. Here we identify phospholipid scramblase 1 (PLSCR1) as a potent cell-autonomous restriction factor against live SARS-CoV-2 infection in parallel genome-wide CRISPR-Cas9 screens of human lung epithelia and hepatocytes before and after stimulation with interferon-γ (IFNγ). IFNγ-induced PLSCR1 not only restricted SARS-CoV-2 USA-WA1/2020, but was also effective against the Delta B.1.617.2 and Omicron BA.1 lineages. Its robust activity extended to other highly pathogenic coronaviruses, was functionally conserved in bats and mice, and interfered with the uptake of SARS-CoV-2 in both the endocytic and the TMPRSS2-dependent fusion routes. Whole-cell 4Pi single-molecule switching nanoscopy together with bipartite nano-reporter assays found that PLSCR1 directly targeted SARS-CoV-2-containing vesicles to prevent spike-mediated fusion and viral escape. A PLSCR1 C-terminal ß-barrel domain-but not lipid scramblase activity-was essential for this fusogenic blockade. Our mechanistic studies, together with reports that COVID-associated PLSCR1 mutations are found in some susceptible people3,4, identify an anti-coronavirus protein that interferes at a late entry step before viral RNA is released into the host-cell cytosol.
Assuntos
COVID-19 , Proteínas de Transferência de Fosfolipídeos , SARS-CoV-2 , Animais , Humanos , Camundongos , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Quirópteros , COVID-19/imunologia , COVID-19/metabolismo , COVID-19/prevenção & controle , COVID-19/virologia , Sequenciamento do Exoma , Hepatócitos/imunologia , Hepatócitos/metabolismo , Interferon gama/imunologia , Pulmão/imunologia , Pulmão/metabolismo , Fusão de Membrana , Proteínas de Transferência de Fosfolipídeos/química , Proteínas de Transferência de Fosfolipídeos/genética , Proteínas de Transferência de Fosfolipídeos/imunologia , Proteínas de Transferência de Fosfolipídeos/metabolismo , SARS-CoV-2/classificação , SARS-CoV-2/imunologia , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Internalização do VírusRESUMO
Objetivo Identificar dentro del grupo de pacientes de alto riesgo a aquellos que presentan más posibilidad de presentar inmunidad postvacunal insuficiente. Método Determinación de títulos de IgG frente a SARS-CoV-2 después de la dosis de recuerdo. Se clasificó la respuesta vacunal como negativa (títulos IgG <34 BAU/ml), indeterminada (títulos 34 - 259 BAU/ml) o positiva (≥260 BAU/ml). Resultados Se incluyeron 765 pacientes (31,25% de los vacunados): 54 (7,1%) en tratamiento con fármacos biológicos, 90 (11,8%) con enfermedad hematológica, 299 (39,1%) con patología oncológica, 304 (39,7%) con trasplante de órgano sólido y 18 (2,4%) con inmunosupresión por otros motivos. Un total de 74 pacientes (9,7%) tuvieron una serología negativa y 45 (5,9%) obtuvieron títulos indeterminados. Por grupo diagnóstico, los pacientes con mayor porcentaje de serología negativa o indeterminada fueron pacientes bajo tratamiento con fármacos biológicos (55,6%, fundamentalmente a expensas de antiCD20), hematológicos (35,4%) y los trasplantados (17,8%, principalmente pulmón y riñón). Los pacientes oncológicos y otros pacientes inmunosuprimidos tuvieron buena respuesta vacunal. Conclusión Los pacientes tratados con fármacos antiCD20, los hematológicos y los trasplantados (fundamentalmente de pulmón y riñón) presentaron mayor riesgo de no desarrollar inmunidad postvacunal. Es fundamental su identificación de cara a individualizar y mejorar su manejo (AU)
Objective To determine which patients within the high-risk group are most likely to have insufficient post-vaccination immunity. Methods Determination of IgG titers against SARS-CoV-2 after the booster dose. Vaccine response was categorized as negative (IgG titers <34 BAU/ml), indeterminate (titers 34 - 259 BAU/ml) or positive (≥ 260 BAU/ml). Results 765 patients were included (31.25% of those vaccinated). 54 (7.1%) on treatment with biologics, 90 (11.8%) with hematologic disease, 299 (39.1%) with oncologic pathology, 304 (39.7%) with solid organ transplant and 18 (2.4%) with immunosuppression for other reasons. 74 patients (9.7%) had negative serology and 45 (5.9%) had indeterminate titers. By diagnostic group, the patients with the highest proportion of negative or indeterminate serology were patients with biologic treatment (55.6%, mainly at expense of antiCD20), hematologic (35.4%) and transplant patients (17.8%, mainly lung and kidney). Oncology and other immunosuppressed patients had a favorable response to vaccination. Conclusion Patients treated with antiCD20 drugs, hematologic patients and transplanted patients (mainly lung and kidney) have a higher risk of not achieving post-vaccination immunity. It is essential to identify them in order to individualize and optimize their management (AU)
Assuntos
Humanos , Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Vacinas Virais/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Imunoglobulina G/imunologiaRESUMO
Targeting the site of infection is a promising strategy for improving vaccine effectivity. To date, licensed COVID-19 vaccines have been administered intramuscularly despite the fact that SARS-CoV-2 is a respiratory virus. Here, we aim to induce local protective mucosal immune responses with an inhaled subunit vaccine candidate, ISR52, based on the SARS-CoV-2 Spike S1 protein. When tested in a lethal challenge hACE2 transgenic SARS-CoV-2 mouse model, intranasal and intratracheal administration of ISR52 provided superior protection against severe infection, compared to the subcutaneous injection of the vaccine. Interestingly for a protein-based vaccine, inhaled ISR52 elicited both CD4 and CD8 T-cell Spike-specific responses that were maintained for at least 6 months in wild-type mice. Induced IgG and IgA responses cross-reacting with several SARS- CoV-2 variants of concern were detected in the lung and in serum and protected animals displayed neutralizing antibodies. Based on our results, we are developing ISR52 as a dry powder formulation for inhalation, that does not require cold-chain distribution or the use of needle administration, for evaluation in a Phase I/II clinical trial.
Assuntos
Vacinas contra COVID-19 , COVID-19 , Vacinas de Subunidades/administração & dosagem , Vacinas de Subunidades/imunologia , Administração por Inalação , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Animais , Camundongos , Reações Cruzadas , COVID-19/prevenção & controle , Camundongos Transgênicos , Anticorpos Antivirais/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Pós , FemininoAssuntos
Febre de Chikungunya , Vírus Chikungunya , Surtos de Doenças , Vacinas Virais , Humanos , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Febre de Chikungunya/epidemiologia , Febre de Chikungunya/imunologia , Febre de Chikungunya/prevenção & controle , Paraguai/epidemiologia , Vacinas , Vacinas Virais/efeitos adversos , Vacinas Virais/imunologia , Vacinas Virais/uso terapêutico , Surtos de Doenças/prevenção & controle , Surtos de Doenças/estatística & dados numéricosRESUMO
Infectious diseases seriously threaten sustainable aquaculture development, resulting in more than $10 billion in economic losses annually. Immersion vaccines are emerging as the key technology for aquatic disease prevention and control. Here, a safe and efficacious candidate immersion vaccine strain (Δorf103r/tk) of infectious spleen and kidney necrosis virus (ISKNV), in which the orf103r and tk genes were knocked out by homologous recombination, is described. Δorf103r/tk was severely attenuated in mandarin fish (Siniperca chuatsi), inducing mild histological lesions, a mortality rate of only 3%, and eliminated within 21 days. A single Δorf103r/tk immersion-administered dose provided long-lasting protection rates over 95% against lethal ISKNV challenge. Δorf103r/tk also robustly stimulated the innate and adaptive immune responses. For example, interferon expression was significantly upregulated, and the production of specific neutralizing antibodies against ISKNV was markedly induced postimmunization. This work provides proof-of-principle evidence for orf103r- and tk-deficient ISKNV for immersion vaccine development to prevent ISKNV disease in aquaculture production. IMPORTANCE Global aquaculture production reached a record of 122.6 million tons in 2020, with a total value of 281.5 billion U.S. dollars (USD). However, approximately 10% of farmed aquatic animal production is lost due to various infectious diseases, resulting in more than 10 billion USD of economic waste every year. Therefore, the development of vaccines to prevent and control aquatic infectious diseases is of great significance. Infectious spleen and kidney necrosis virus (ISKNV) infection occurs in more than 50 species of freshwater and marine fish and has caused great economic losses to the mandarin fish farming industry in China during the past few decades. Thus, it is listed as a certifiable disease by the World Organization for Animal Health (OIE). Herein, a safe and efficient double-gene-deleted live attenuated immersion vaccine against ISKNV was developed, providing an example for the development of aquatic gene-deleted live attenuated immersion vaccine.
Assuntos
Doenças dos Peixes , Iridoviridae , Vacinas Virais , Animais , Doenças dos Peixes/imunologia , Doenças dos Peixes/virologia , Peixes , Imersão , Iridoviridae/genética , Iridoviridae/imunologia , Iridoviridae/isolamento & purificação , Iridoviridae/patogenicidade , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacinas Virais/genética , Vacinas Virais/imunologia , Linhagem Celular , Expressão Gênica/imunologia , Anticorpos Antivirais/imunologiaRESUMO
Background Although vaccination has considerably reduced the risk of hospitalization and death from COVID19, the impact of vaccination and anti-SARS-CoV-2 antibody status on the outcome of patients who required hospitalization has been poorly investigated. Material and methods A prospective observational study in 232 patients hospitalized for COVID19 was carried out from October 2021 to January 2022 to evaluate the role on patient outcome of their vaccination and anti-SARS-CoV-2 antibody status and titer, comorbidities, analytical determinations, clinical presentation at admission, treatments and requirements for respiratory support. Cox regression and survival analyzes were performed. The SPSS and R programs were used. Results Patients with complete vaccination schedule had higher S-protein antibody titers (log10 3.73 [2.834.6]UI/ml vs 1.6 [2.992.61]UI/ml; p<0.001), lower probability of radiographic worsening (21.6% vs. 35.4%; p=0.005), less likely required high doses of dexamethasone (28.4% vs. 45.4%; p=0.012), high-flow oxygen (20.6% vs. 35.4%; p=0.02), ventilation (13.7% vs, 33.8%; p=0.001) and intensive care admissions (10.8% vs. 32.6%; p<0.001). Remdesivir (HR=0.38; p<0.001) and complete vaccination schedule (HR=0.34; p=0.008) were protective factors. No differences in antibody status were detected between groups (HR=0.58; p=0.219). Conclusions SARS-CoV-2 vaccination was associated with higher S-protein antibody titers and lower probability of radiological progression, immunomodulators requirement and respiratory support or death. However, vaccination but not antibody titters protected from adverse events pointing a role of immune-protective mechanisms in addition to humoral response (AU)
Antecedentes Aunque la vacunación ha reducido considerablemente el riesgo de hospitalización y muerte por COVID-19, se ha investigado poco el impacto de la vacunación y el estado de los anticuerpos anti-SARS-CoV-2 en la evolución de los pacientes que requieren hospitalización. Material y métodos Se realizó un estudio observacional prospectivo en 232 pacientes hospitalizados por COVID-19 desde octubre del 2021 hasta enero del 2022 para evaluar el impacto en la evolución clínica del estado vacunal, el título de anticuerpos anti-SARS-CoV-2, la presencia de comorbilidades, analítica, la clínica al ingreso, tratamientos y soporte respiratorio. Se realizaron análisis de supervivencia y regresión de Cox. Se utilizaron los programas SPSS y «R». Resultados Los pacientes con esquema de vacunación completo presentaron títulos de anticuerpos contra la proteína S más elevados (log10 3,73 [2,83-4,6] UI/mL vs. 1,6 [2,99-2,61] UI/mL; p < 0,001), menor probabilidad de empeoramiento radiográfico (21,6 vs. 35,4%; p = 0,005), requirieron con menor probabilidad dosis elevadas de dexametasona (28,4 vs. 45,4%; p = 0,012), oxígeno de alto flujo (20,6 vs. 35,4%; p = 0,02), ventilación (13,7 vs. 33,8%; p = 0,001) e ingresos en cuidados intensivos (10,8 vs. 32,6%; p < 0,001). El remdesivir (HR = 0,38; p < 0,001) y el esquema completo de vacunación (HR = 0,34; p = 0,008) fueron factores protectores de mala evolución. No se detectaron diferencias en el estado de los anticuerpos entre los grupos (HR = 0,58; p = 0,219). Conclusiones La vacunación contra el SARS-CoV-2 se asoció con mayores títulos de anticuerpos contra la proteína S y menor probabilidad de progresión radiológica, requerimiento de inmunomoduladores y soporte respiratorio o muerte. Sin embargo, la vacunación, pero no los títulos de anticuerpos, protegió de los eventos adversos, lo que indica un papel de los mecanismos de protección inmunológica además de la respuesta humoral (AU)
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/imunologia , Vacinas Virais/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Betacoronavirus/imunologia , Estudos ProspectivosRESUMO
SARS-CoV-2 has resulted in high levels of morbidity and mortality world-wide, and severe complications can occur in older populations. Humoral immunity induced by authorized vaccines wanes within 6 months, and frequent boosts may only offer transient protection. GRT-R910 is an investigational self-amplifying mRNA (samRNA)-based SARS-CoV-2 vaccine delivering full-length Spike and selected conserved non-Spike T cell epitopes. This study reports interim analyses for a phase I open-label dose-escalation trial evaluating GRT-R910 in previously vaccinated healthy older adults (NCT05148962). Primary endpoints of safety and tolerability were assessed. Most solicited local and systemic adverse events (AEs) following GRT-R910 dosing were mild to moderate and transient, and no treatment-related serious AEs were observed. The secondary endpoint of immunogenicity was assessed via IgG binding assays, neutralization assays, interferon-gamma ELISpot, and intracellular cytokine staining. Neutralizing antibody titers against ancestral Spike and variants of concern were boosted or induced by GRT-R910 and, contrasting to authorized vaccines, persisted through at least 6 months after the booster dose. GRT-R910 increased and/or broadened functional Spike-specific T cell responses and primed functional T cell responses to conserved non-Spike epitopes. This study is limited due to small sample size, and additional data from ongoing studies will be required to corroborate these interim findings.
Assuntos
COVID-19 , RNA Mensageiro/genética , COVID-19/prevenção & controle , Humanos , Idoso , Masculino , Feminino , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Ensaios Clínicos como Assunto , Anticorpos Antivirais/imunologia , Anticorpos Neutralizantes/imunologia , Linfócitos T/imunologiaRESUMO
We identified neutralizing monoclonal antibodies against severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) variants (including Omicron variants BA.5 and BA.2.75) from individuals who received two doses of mRNA vaccination after they had been infected with the D614G virus. We named them MO1, MO2, and MO3. Among them, MO1 showed particularly high neutralizing activity against authentic variants: D614G, Delta, BA.1, BA.1.1, BA.2, BA.2.75, and BA.5. Furthermore, MO1 suppressed BA.5 infection in hamsters. A structural analysis revealed that MO1 binds to the conserved epitope of seven variants, including Omicron variants BA.5 and BA.2.75, in the receptor-binding domain of the spike protein. MO1 targets an epitope conserved among Omicron variants BA.1, BA.2, and BA.5 in a unique binding mode. Our findings confirm that D614G-derived vaccination can induce neutralizing antibodies that recognize the epitopes conserved among the SARS-CoV-2 variants. IMPORTANCE Omicron variants of SARS-CoV-2 acquired escape ability from host immunity and authorized antibody therapeutics and thereby have been spreading worldwide. We reported that patients infected with an early SARS-CoV-2 variant, D614G, and who received subsequent two-dose mRNA vaccination have high neutralizing antibody titer against Omicron lineages. It was speculated that the patients have neutralizing antibodies broadly effective against SARS-CoV-2 variants by targeting common epitopes. Here, we explored human monoclonal antibodies from B cells of the patients. One of the monoclonal antibodies, named MO1, showed high potency against broad SARS-CoV-2 variants including BA.2.75 and BA.5 variants. The results prove that monoclonal antibodies that have common neutralizing epitopes among several Omicrons were produced in patients infected with D614G and who received mRNA vaccination.
Assuntos
Anticorpos Monoclonais , Anticorpos Antivirais , COVID-19 , Epitopos , Animais , Cricetinae , Humanos , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/virologia , Epitopos/imunologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Masculino , Feminino , Pessoa de Meia-IdadeRESUMO
Rapidly evolving influenza A viruses (IAVs) and influenza B viruses (IBVs) are major causes of recurrent lower respiratory tract infections. Current influenza vaccines elicit antibodies predominantly to the highly variable head region of haemagglutinin and their effectiveness is limited by viral drift1 and suboptimal immune responses2. Here we describe a neuraminidase-targeting monoclonal antibody, FNI9, that potently inhibits the enzymatic activity of all group 1 and group 2 IAVs, as well as Victoria/2/87-like, Yamagata/16/88-like and ancestral IBVs. FNI9 broadly neutralizes seasonal IAVs and IBVs, including the immune-evading H3N2 strains bearing an N-glycan at position 245, and shows synergistic activity when combined with anti-haemagglutinin stem-directed antibodies. Structural analysis reveals that D107 in the FNI9 heavy chain complementarity-determinant region 3 mimics the interaction of the sialic acid carboxyl group with the three highly conserved arginine residues (R118, R292 and R371) of the neuraminidase catalytic site. FNI9 demonstrates potent prophylactic activity against lethal IAV and IBV infections in mice. The unprecedented breadth and potency of the FNI9 monoclonal antibody supports its development for the prevention of influenza illness by seasonal and pandemic viruses.
Assuntos
Anticorpos Antivirais , Especificidade de Anticorpos , Vírus da Influenza A , Vírus da Influenza B , Vacinas contra Influenza , Influenza Humana , Mimetismo Molecular , Neuraminidase , Animais , Humanos , Camundongos , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Antivirais/química , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/uso terapêutico , Especificidade de Anticorpos/imunologia , Arginina/química , Domínio Catalítico , Hemaglutininas Virais/imunologia , Vírus da Influenza A/classificação , Vírus da Influenza A/enzimologia , Vírus da Influenza A/imunologia , Vírus da Influenza A Subtipo H3N2/enzimologia , Vírus da Influenza A Subtipo H3N2/imunologia , Vírus da Influenza B/classificação , Vírus da Influenza B/enzimologia , Vírus da Influenza B/imunologia , Vacinas contra Influenza/química , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/uso terapêutico , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Neuraminidase/antagonistas & inibidores , Neuraminidase/química , Neuraminidase/imunologia , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Estações do Ano , Ácidos Siálicos/químicaRESUMO
Consensus grows for abandoning the ancestral strain to improve immune responses.
Assuntos
Vacinas contra COVID-19 , COVID-19 , Imunização Secundária , Imunogenicidade da Vacina , SARS-CoV-2 , Humanos , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , Vacinação , SARS-CoV-2/imunologiaRESUMO
Researchers aim to make monoclonal antibodies that mutations in SARS-CoV-2 won't thwart.
Assuntos
Anticorpos Monoclonais , Anticorpos Antivirais , COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Humanos , COVID-19/prevenção & controle , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/uso terapêutico , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologiaRESUMO
Inactivated vaccine is one of the platforms employed in COVID-19 vaccines. Inactivated vaccines have been associated with concerns of antibody-dependent enhancement (ADE) and original antigenic sin (OAS), which are related to non-neutralising or poorly neutralising antibodies against the pathogen. Since inactivated COVID-19 vaccines use whole-SARS-CoV-2 virus as the immunogen, they are expected to generate antibodies against non-spike structural proteins, which are highly conservative across variants of SARS-CoV-2. These antibodies against non-spike structural proteins have found to be largely non-neutralising or poorly neutralising in nature. Hence, inactivated COVID-19 vaccines could possibly be associated with ADE and OAS, especially as novel variants emerge. This article explores the potential concern of ADE and OAS in the context of inactivated COVID-19 vaccine, and outlines the future research directions.
Assuntos
Vacinas contra COVID-19 , Vacinas contra COVID-19/imunologia , Anticorpos Antivirais/imunologia , COVID-19/prevenção & controle , HumanosRESUMO
The primary two-dose SARS-CoV-2 mRNA vaccine series are strongly immunogenic in humans, but the emergence of highly infectious variants necessitated additional doses and the development of vaccines aimed at the new variants1-4. SARS-CoV-2 booster immunizations in humans primarily recruit pre-existing memory B cells5-9. However, it remains unclear whether the additional doses induce germinal centre reactions whereby re-engaged B cells can further mature, and whether variant-derived vaccines can elicit responses to variant-specific epitopes. Here we show that boosting with an mRNA vaccine against the original monovalent SARS-CoV-2 mRNA vaccine or the bivalent B.1.351 and B.1.617.2 (Beta/Delta) mRNA vaccine induced robust spike-specific germinal centre B cell responses in humans. The germinal centre response persisted for at least eight weeks, leading to significantly more mutated antigen-specific bone marrow plasma cell and memory B cell compartments. Spike-binding monoclonal antibodies derived from memory B cells isolated from individuals boosted with either the original SARS-CoV-2 spike protein, bivalent Beta/Delta vaccine or a monovalent Omicron BA.1-based vaccine predominantly recognized the original SARS-CoV-2 spike protein. Nonetheless, using a more targeted sorting approach, we isolated monoclonal antibodies that recognized the BA.1 spike protein but not the original SARS-CoV-2 spike protein from individuals who received the mRNA-1273.529 booster; these antibodies were less mutated and recognized novel epitopes within the spike protein, suggesting that they originated from naive B cells. Thus, SARS-CoV-2 booster immunizations in humans induce robust germinal centre B cell responses and can generate de novo B cell responses targeting variant-specific epitopes.
Assuntos
Linfócitos B , Vacinas contra COVID-19 , COVID-19 , Centro Germinativo , Imunização Secundária , Humanos , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos B/citologia , Linfócitos B/imunologia , Centro Germinativo/citologia , Centro Germinativo/imunologia , Plasmócitos/citologia , Plasmócitos/imunologia , Células B de Memória/citologia , Células B de Memória/imunologia , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologiaRESUMO
Although many approaches have been developed for the quick assessment of SARS-CoV-2 infection, few of them are devoted to the detection of the neutralizing antibody, which is essential for assessing the effectiveness of vaccines. Herein, we developed a tri-mode lateral flow immunoassay (LFIA) platform based on gold-silver alloy hollow nanoshells (Au-Ag HNSs) for the sensitive and accurate quantification of neutralizing antibodies. By tuning the shell-to-core ratio, the surface plasmon resonance (SPR) absorption band of the Au-Ag HNSs is located within the near infrared (NIR) region, endowing them with an excellent photothermal effect under the irradiation of optical maser at 808 nm. Further, the Raman reporter molecule 4-mercaptobenzoic acid (MBA) was immobilized on the gold-silver alloy nanoshell to obtain an enhanced SERS signal. Thus, these Au-Ag HNSs could provide colorimetric, photothermal and SERS signals, with which, tri-mode strips for SARS-CoV-2 neutralizing antibody detection were constructed by competitive immunoassay. Since these three kinds of signals could complement one another, a more accurate detection was achieved. The tri-mode LFIA achieved a quantitative detection with detection limit of 20 ng/mL. Moreover, it also successfully detected the serum samples from 98 vaccinated volunteers with 79 positive results, exhibiting great application value in neutralizing antibody detection.
Assuntos
Anticorpos Neutralizantes , COVID-19 , Imunoensaio , Nanoconchas , SARS-CoV-2 , Análise Espectral Raman , Humanos , Ligas , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/isolamento & purificação , Anticorpos Antivirais/imunologia , Colorimetria/métodos , COVID-19/diagnóstico , COVID-19/imunologia , Ouro , Imunoensaio/instrumentação , Imunoensaio/métodos , Nanopartículas Metálicas , SARS-CoV-2/imunologia , Prata , Análise Espectral Raman/métodosAssuntos
Anticorpos Neutralizantes , Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Humanos , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , SARS-CoV-2/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/uso terapêutico , Vacinas de Subunidades/imunologia , Vacinas de Subunidades/uso terapêuticoRESUMO
Protein subunit vaccines have been widely used to combat infectious diseases, including the current COVID-19 pandemic. Adjuvants play the key role in shaping the quality and magnitude of the immune response to protein and inactivated vaccines. We previously developed a protein subunit COVID-19 vaccine, termed ZF2001, based on an aluminium hydroxide-adjuvanted tandem-repeat dimeric receptor-binding domain (RBD) of the viral spike (S) protein. Here, we described the use of a squalene-based oil-in-water adjuvant, Sepivac SWE™ (abbreviated to SWE), to further improve the immunogenicity of this RBD-dimer-based subunit vaccines. Compared with ZF2001, SWE adjuvant enhanced the antibody and CD4+ T-cell responses in mice with at least 10 fold of dose sparing compared with ZF2001 adjuvanted with aluminium hydroxide. SWE-adjuvanted vaccine protected mice against SARS-CoV-2 challenge. To ensure adequate protection against the currently circulating Omicron variant, we evaluated this adjuvant in combination with Delta-Omicron chimeric RBD-dimer. SWE significantly increased antibody responses compared with aluminium hydroxide adjuvant and afforded greater neutralization breadth. These data highlight the advantage of emulsion-based adjuvants to elevate the protective immune response of protein subunit COVID-19 vaccines.
