Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
Nature ; 592(7855): 623-628, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33762730

RESUMEN

Influenza vaccines that confer broad and durable protection against diverse viral strains would have a major effect on global health, as they would lessen the need for annual vaccine reformulation and immunization1. Here we show that computationally designed, two-component nanoparticle immunogens2 induce potently neutralizing and broadly protective antibody responses against a wide variety of influenza viruses. The nanoparticle immunogens contain 20 haemagglutinin glycoprotein trimers in an ordered array, and their assembly in vitro enables the precisely controlled co-display of multiple distinct haemagglutinin proteins in defined ratios. Nanoparticle immunogens that co-display the four haemagglutinins of licensed quadrivalent influenza vaccines elicited antibody responses in several animal models against vaccine-matched strains that were equivalent to or better than commercial quadrivalent influenza vaccines, and simultaneously induced broadly protective antibody responses to heterologous viruses by targeting the subdominant yet conserved haemagglutinin stem. The combination of potent receptor-blocking and cross-reactive stem-directed antibodies induced by the nanoparticle immunogens makes them attractive candidates for a supraseasonal influenza vaccine candidate with the potential to replace conventional seasonal vaccines3.


Asunto(s)
Anticuerpos ampliamente neutralizantes/inmunología , Virus de la Influenza A/clasificación , Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Gripe Humana/inmunología , Gripe Humana/prevención & control , Nanomedicina , Nanopartículas , Animales , Modelos Animales de Enfermedad , Femenino , Hurones/inmunología , Hurones/virología , Glicoproteínas Hemaglutininas del Virus de la Influenza/química , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Humanos , Subtipo H1N1 del Virus de la Influenza A/inmunología , Subtipo H3N2 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/administración & dosificación , Vacunas contra la Influenza/química , Gripe Humana/virología , Masculino , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares
2.
Nature ; 586(7830): 567-571, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32756549

RESUMEN

A vaccine for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is needed to control the coronavirus disease 2019 (COVID-19) global pandemic. Structural studies have led to the development of mutations that stabilize Betacoronavirus spike proteins in the prefusion state, improving their expression and increasing immunogenicity1. This principle has been applied to design mRNA-1273, an mRNA vaccine that encodes a SARS-CoV-2 spike protein that is stabilized in the prefusion conformation. Here we show that mRNA-1273 induces potent neutralizing antibody responses to both wild-type (D614) and D614G mutant2 SARS-CoV-2 as well as CD8+ T cell responses, and protects against SARS-CoV-2 infection in the lungs and noses of mice without evidence of immunopathology. mRNA-1273 is currently in a phase III trial to evaluate its efficacy.


Asunto(s)
Betacoronavirus/inmunología , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/prevención & control , Pandemias/prevención & control , Neumonía Viral/inmunología , Neumonía Viral/prevención & control , Vacunas Virales/inmunología , Vacuna nCoV-2019 mRNA-1273 , Animales , Anticuerpos Neutralizantes/inmunología , Betacoronavirus/genética , Linfocitos T CD8-positivos/inmunología , COVID-19 , Vacunas contra la COVID-19 , Ensayos Clínicos Fase III como Asunto , Infecciones por Coronavirus/genética , Infecciones por Coronavirus/virología , Femenino , Pulmón/inmunología , Pulmón/virología , Ratones , Mutación , Nariz/inmunología , Nariz/virología , Neumonía Viral/virología , ARN Mensajero/genética , ARN Viral/genética , SARS-CoV-2 , Células TH1/inmunología , Receptor Toll-Like 4/agonistas , Receptor Toll-Like 4/inmunología , Vacunas Virales/química , Vacunas Virales/genética
3.
Emerg Infect Dis ; 26(9): 1998-2004, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32620182

RESUMEN

To determine prevalence of, seroprevalence of, and potential exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among a cohort of evacuees returning to the United States from Wuhan, China, in January 2020, we conducted a cross-sectional study of quarantined evacuees from 1 repatriation flight. Overall, 193 of 195 evacuees completed exposure surveys and submitted upper respiratory or serum specimens or both at arrival in the United States. Nearly all evacuees had taken preventive measures to limit potential exposure while in Wuhan, and none had detectable SARS-CoV-2 in upper respiratory tract specimens, suggesting the absence of asymptomatic respiratory shedding among this group at the time of testing. Evidence of antibodies to SARS-CoV-2 was detected in 1 evacuee, who reported experiencing no symptoms or high-risk exposures in the previous 2 months. These findings demonstrated that this group of evacuees posed a low risk of introducing SARS-CoV-2 to the United States.


Asunto(s)
Betacoronavirus , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , Cuarentena/estadística & datos numéricos , Adolescente , Adulto , Anciano , COVID-19 , Prueba de COVID-19 , Niño , Preescolar , Infecciones por Coronavirus/diagnóstico , Estudios Transversales , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Pandemias , Prevalencia , SARS-CoV-2 , Estudios Seroepidemiológicos , Viaje , Estados Unidos/epidemiología , Adulto Joven
4.
Cell Rep ; 42(12): 113552, 2023 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-38096058

RESUMEN

Immunogen design approaches aim to control the specificity and quality of antibody responses elicited by next-generation vaccines. Here, we use computational protein design to generate a nanoparticle vaccine platform based on the receptor-binding domain (RBD) of influenza hemagglutinin (HA) that enables precise control of antigen conformation and spacing. HA RBDs are presented as either monomers or native-like closed trimers that are connected to the underlying nanoparticle by a rigid linker that is modularly extended to precisely control antigen spacing. Nanoparticle immunogens with decreased spacing between trimeric RBDs elicit antibodies with improved hemagglutination inhibition and neutralization potency as well as binding breadth across diverse H1 HAs. Our "trihead" nanoparticle immunogen platform provides insights into anti-HA immunity, establishes antigen spacing as an important parameter in structure-based vaccine design, and embodies several design features that could be used in next-generation vaccines against influenza and other viruses.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Nanopartículas , Infecciones por Orthomyxoviridae , Humanos , Gripe Humana/prevención & control , Anticuerpos Antivirales , Formación de Anticuerpos , Glicoproteínas Hemaglutininas del Virus de la Influenza , Vacunación , Hemaglutininas
5.
Nat Commun ; 14(1): 6195, 2023 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-37794071

RESUMEN

Multivalent antigen display is a fast-growing area of interest toward broadly protective vaccines. Current nanoparticle-based vaccine candidates demonstrate the ability to confer antibody-mediated immunity against divergent strains of notably mutable viruses. In coronaviruses, this work is predominantly aimed at targeting conserved epitopes of the receptor binding domain. However, targeting conserved non-RBD epitopes could limit the potential for antigenic escape. To explore new potential targets, we engineered protein nanoparticles displaying coronavirus prefusion-stabilized spike (CoV_S-2P) trimers derived from MERS-CoV, SARS-CoV-1, SARS-CoV-2, hCoV-HKU1, and hCoV-OC43 and assessed their immunogenicity in female mice. Monotypic SARS-1 nanoparticles elicit cross-neutralizing antibodies against MERS-CoV and protect against MERS-CoV challenge. MERS and SARS nanoparticles elicit S1-focused antibodies, revealing a conserved site on the S N-terminal domain. Moreover, mosaic nanoparticles co-displaying distinct CoV_S-2P trimers elicit antibody responses to distant cross-group antigens and protect male and female mice against MERS-CoV challenge. Our findings will inform further efforts toward the development of pan-coronavirus vaccines.


Asunto(s)
Coronavirus del Síndrome Respiratorio de Oriente Medio , Vacunas , Masculino , Femenino , Animales , Ratones , Anticuerpos Antivirales , Formación de Anticuerpos , Epítopos/metabolismo , Glicoproteína de la Espiga del Coronavirus , Anticuerpos Neutralizantes
6.
Front Immunol ; 12: 772864, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34956199

RESUMEN

Nipah virus (NiV) represents a significant pandemic threat with zoonotic transmission from bats-to-humans with almost annual regional outbreaks characterized by documented human-to-human transmission and high fatality rates. Currently, no vaccine against NiV has been approved. Structure-based design and protein engineering principles were applied to stabilize the fusion (F) protein in its prefusion trimeric conformation (pre-F) to improve expression and increase immunogenicity. We covalently linked the stabilized pre-F through trimerization domains at the C-terminus to three attachment protein (G) monomers, forming a chimeric design. These studies detailed here focus on mRNA delivery of NiV immunogens in mice, assessment of mRNA immunogen-specific design elements and their effects on humoral and cellular immunogenicity. The pre-F/G chimera elicited a strong neutralizing antibody response and a superior NiV-specific Tfh and other effector T cell response compared to G alone across both the mRNA and protein platforms. These findings enabled final candidate selection of pre-F/G Fd for clinical development.


Asunto(s)
Antígenos Virales/genética , Liposomas/administración & dosificación , Nanopartículas/administración & dosificación , Virus Nipah/inmunología , Proteínas del Envoltorio Viral/genética , Proteínas Virales de Fusión/genética , Vacunas Virales/administración & dosificación , Vacunas de ARNm/administración & dosificación , Animales , Antígenos Virales/inmunología , Femenino , Inmunoglobulina G/sangre , Ratones , Asociación entre el Sector Público-Privado , ARN Mensajero/administración & dosificación , Linfocitos T/inmunología , Proteínas del Envoltorio Viral/inmunología , Proteínas Virales de Fusión/inmunología
7.
Front Immunol ; 11: 842, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32595632

RESUMEN

Licensed vaccines or therapeutics are rarely available for pathogens with epidemic or pandemic potential. Developing interventions for specific pathogens and defining generalizable approaches for related pathogens is a global priority and inherent to the UN Sustainable Development Goals. Nipah virus (NiV) poses a significant epidemic threat, and zoonotic transmission from bats-to-humans with high fatality rates occurs almost annually. Human-to-human transmission of NiV has been documented in recent outbreaks leading public health officials and government agencies to declare an urgent need for effective vaccines and therapeutics. Here, we evaluate NiV vaccine antigen design options including the fusion glycoprotein (F) and the major attachment glycoprotein (G). A stabilized prefusion F (pre-F), multimeric G constructs, and chimeric proteins containing both pre-F and G were developed as protein subunit candidate vaccines. The proteins were evaluated for antigenicity and structural integrity using kinetic binding assays, electron microscopy, and other biophysical properties. Immunogenicity of the vaccine antigens was evaluated in mice. The stabilized pre-F trimer and hexameric G immunogens both induced serum neutralizing activity in mice, while the post-F trimer immunogen did not elicit neutralizing activity. The pre-F trimer covalently linked to three G monomers (pre-F/G) induced potent neutralizing antibody activity, elicited responses to the greatest diversity of antigenic sites, and is the lead candidate for clinical development. The specific stabilizing mutations and immunogen designs utilized for NiV were successfully applied to other henipaviruses, supporting the concept of identifying generalizable solutions for prototype pathogens as an approach to pandemic preparedness.


Asunto(s)
Antígenos Virales/inmunología , Infecciones por Henipavirus/prevención & control , Inmunogenicidad Vacunal , Virus Nipah/química , Virus Nipah/inmunología , Vacunas Virales/inmunología , Animales , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Células HEK293 , Infecciones por Henipavirus/virología , Humanos , Inmunización/métodos , Ratones , Ratones Endogámicos C57BL , Transfección , Proteínas Virales de Fusión/inmunología , Internalización del Virus
8.
bioRxiv ; 2020 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-32676596

RESUMEN

Antigens displayed on self-assembling nanoparticles can stimulate strong immune responses and have been playing an increasingly prominent role in structure-based vaccines. However, the development of such immunogens is often complicated by inefficiencies in their production. To alleviate this issue, we developed a plug-and-play platform using the spontaneous isopeptide-bond formation of the SpyTag:SpyCatcher system to display trimeric antigens on self-assembling nanoparticles, including the 60-subunit Aquifex aeolicus lumazine synthase (LuS) and the 24-subunit Helicobacter pylori ferritin. LuS and ferritin coupled to SpyTag expressed well in a mammalian expression system when an N-linked glycan was added to the nanoparticle surface. The respiratory syncytial virus fusion (F) glycoprotein trimer - stabilized in the prefusion conformation and fused with SpyCatcher - could be efficiently conjugated to LuS-SpyTag or ferritin-SpyTag, enabling multivalent display of F trimers with prefusion antigenicity. Similarly, F-glycoprotein trimers from human parainfluenza virus-type 3 and spike-glycoprotein trimers from SARS-CoV-2 could be displayed on LuS nanoparticles with decent yield and antigenicity. Notably, murine vaccination with the SARS-CoV-2 spike-LuS nanoparticles elicited ~25-fold higher neutralizing responses, weight-per-weight relative to spike alone. The versatile platform described here thus allows for multivalent plug-and-play presentation on self-assembling nanoparticles of trimeric viral antigens, with SARS-CoV-2 spike-LuS nanoparticles inducing particularly potent neutralizing responses.

9.
Sci Rep ; 10(1): 18149, 2020 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-33097791

RESUMEN

Antigens displayed on self-assembling nanoparticles can stimulate strong immune responses and have been playing an increasingly prominent role in structure-based vaccines. However, the development of such immunogens is often complicated by inefficiencies in their production. To alleviate this issue, we developed a plug-and-play platform using the spontaneous isopeptide-bond formation of the SpyTag:SpyCatcher system to display trimeric antigens on self-assembling nanoparticles, including the 60-subunit Aquifex aeolicus lumazine synthase (LuS) and the 24-subunit Helicobacter pylori ferritin. LuS and ferritin coupled to SpyTag expressed well in a mammalian expression system when an N-linked glycan was added to the nanoparticle surface. The respiratory syncytial virus fusion (F) glycoprotein trimer-stabilized in the prefusion conformation and fused with SpyCatcher-could be efficiently conjugated to LuS-SpyTag or ferritin-SpyTag, enabling multivalent display of F trimers with prefusion antigenicity. Similarly, F-glycoprotein trimers from human parainfluenza virus-type 3 and spike-glycoprotein trimers from SARS-CoV-2 could be displayed on LuS nanoparticles with decent yield and antigenicity. Notably, murine vaccination with 0.08 µg of SARS-CoV-2 spike-LuS nanoparticle elicited similar neutralizing responses as 2.0 µg of spike, which was ~ 25-fold higher on a weight-per-weight basis. The versatile platform described here thus allows for multivalent plug-and-play presentation on self-assembling nanoparticles of trimeric viral antigens, with SARS-CoV-2 spike-LuS nanoparticles inducing particularly potent neutralizing responses.


Asunto(s)
Antígenos/inmunología , Betacoronavirus/metabolismo , Nanopartículas/química , Glicoproteína de la Espiga del Coronavirus/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Antígenos/genética , Antígenos/metabolismo , Aquifex , Bacterias/enzimología , Proteínas Bacterianas/genética , Betacoronavirus/aislamiento & purificación , COVID-19 , Infecciones por Coronavirus , Ferritinas/genética , Helicobacter pylori/metabolismo , Humanos , Ratones , Complejos Multienzimáticos/genética , Pruebas de Neutralización , Pandemias , Neumonía Viral , Multimerización de Proteína , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/inmunología , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo , Propiedades de Superficie
10.
bioRxiv ; 2020 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-32511332

RESUMEN

Since emergence of SARS-CoV-2 in late 2019, there has been a critical need to understand prevalence, transmission patterns, to calculate the burden of disease and case fatality rates. Molecular diagnostics, the gold standard for identifying viremic cases, are not ideal for determining true case counts and rates of asymptomatic infection. Serological detection of SARS-CoV-2 specific antibodies can contribute to filling these knowledge gaps. In this study, we describe optimization and validation of a SARS-CoV-2-specific-enzyme linked immunosorbent assay (ELISA) using the prefusion-stabilized form of the spike protein [1]. We performed receiver operator characteristic (ROC) analyses to define the specificities and sensitivities of the optimized assay and examined cross reactivity with immune sera from persons confirmed tohave had infections with other coronaviruses. These assays will be used to perform contact investigations and to conduct large-scale, cross sectional surveillance to define disease burden in the population.

11.
Nat Commun ; 11(1): 791, 2020 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-32034141

RESUMEN

The conserved hemagglutinin (HA) stem has been a focus of universal influenza vaccine efforts. Influenza A group 1 HA stem-nanoparticles have been demonstrated to confer heterosubtypic protection in animals; however, the protection does not extend to group 2 viruses, due in part to differences in glycosylation between group 1 and 2 stems. Here, we show that introducing the group 2 glycan at Asn38HA1 to a group 1 stem-nanoparticle (gN38 variant) based on A/New Caledonia/20/99 (H1N1) broadens antibody responses to cross-react with group 2 HAs. Immunoglobulins elicited by the gN38 variant provide complete protection against group 2 H7N9 virus infection, while the variant loses protection against a group 1 H5N1 virus. The N38HA1 glycan thus is pivotal in directing antibody responses by controlling access to group-determining stem epitopes. Precise targeting of stem-directed antibody responses to the site of vulnerability by glycan repositioning may be a step towards achieving cross-group influenza protection.


Asunto(s)
Glicoproteínas Hemaglutininas del Virus de la Influenza/química , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Vacunas contra la Influenza/inmunología , Nanopartículas/química , Polisacáridos/química , Animales , Anticuerpos Antivirales/inmunología , Especificidad de Anticuerpos , Asparagina/química , Asparagina/metabolismo , Anticuerpos ampliamente neutralizantes/inmunología , Reacciones Cruzadas , Epítopos/inmunología , Femenino , Glicosilación , Glicoproteínas Hemaglutininas del Virus de la Influenza/metabolismo , Inmunoglobulinas/inmunología , Subtipo H7N9 del Virus de la Influenza A/patogenicidad , Ratones Endogámicos BALB C , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/prevención & control
12.
Elife ; 92020 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-32748788

RESUMEN

Multivalent presentation of viral glycoproteins can substantially increase the elicitation of antigen-specific antibodies. To enable a new generation of anti-viral vaccines, we designed self-assembling protein nanoparticles with geometries tailored to present the ectodomains of influenza, HIV, and RSV viral glycoprotein trimers. We first de novo designed trimers tailored for antigen fusion, featuring N-terminal helices positioned to match the C termini of the viral glycoproteins. Trimers that experimentally adopted their designed configurations were incorporated as components of tetrahedral, octahedral, and icosahedral nanoparticles, which were characterized by cryo-electron microscopy and assessed for their ability to present viral glycoproteins. Electron microscopy and antibody binding experiments demonstrated that the designed nanoparticles presented antigenically intact prefusion HIV-1 Env, influenza hemagglutinin, and RSV F trimers in the predicted geometries. This work demonstrates that antigen-displaying protein nanoparticles can be designed from scratch, and provides a systematic way to investigate the influence of antigen presentation geometry on the immune response to vaccination.


Vaccines train the immune system to recognize a specific virus or bacterium so that the body can be better prepared against these harmful agents. To do so, many vaccines contain viral molecules called glycoproteins, which are specific to each type of virus. Glycoproteins that sit at the surface of the virus can act as 'keys' that recognize and unlock the cells of certain organisms, leading to viral infection. To ensure a stronger immune response, glycoproteins in vaccines are often arranged on a protein scaffolding which can mimic the shape of the virus of interest and trigger a strong immune response. Many scaffoldings, however, are currently made from natural proteins which cannot always display viral glycoproteins. Here, Ueda, Antanasijevic et al. developed a method that allows for the design of artificial proteins which can serve as scaffolding for viral glycoproteins. This approach was tested using three viruses: influenza, HIV, and RSV ­ a virus responsible for bronchiolitis. The experiments showed that in each case, the relevant viral glycoproteins could attach themselves to the scaffolding. These structures could then assemble themselves into vaccine particles with predicted geometrical shapes, which mimicked the virus and maximized the response from the immune system. Designing artificial scaffolding for viral glycoproteins gives greater control over vaccine design, allowing scientists to manipulate the shape of vaccine particles and test the impact on the immune response. Ultimately, the approach developed by Ueda, Antanasijevic et al. could lead to vaccines that are more efficient and protective, including against viruses for which there is currently no suitable scaffolding.


Asunto(s)
Antígenos Virales/inmunología , Glicoproteínas/inmunología , Inmunidad Humoral , Vacunas contra la Influenza/inmunología , Nanopartículas/química , Antígenos Virales/química , Microscopía por Crioelectrón , Glicoproteínas/química , Humanos , Vacunas contra la Influenza/química , Vacunación
13.
bioRxiv ; 2020 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-32577634

RESUMEN

A SARS-CoV-2 vaccine is needed to control the global COVID-19 public health crisis. Atomic-level structures directed the application of prefusion-stabilizing mutations that improved expression and immunogenicity of betacoronavirus spike proteins. Using this established immunogen design, the release of SARS-CoV-2 sequences triggered immediate rapid manufacturing of an mRNA vaccine expressing the prefusion-stabilized SARS-CoV-2 spike trimer (mRNA-1273). Here, we show that mRNA-1273 induces both potent neutralizing antibody and CD8 T cell responses and protects against SARS-CoV-2 infection in lungs and noses of mice without evidence of immunopathology. mRNA-1273 is currently in a Phase 2 clinical trial with a trajectory towards Phase 3 efficacy evaluation.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA