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1.
Virology ; 557: 70-85, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33676349

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged into the human population in late 2019 and caused the global COVID-19 pandemic. SARS-CoV-2 has spread to more than 215 countries and infected many millions of people. Despite the introduction of numerous governmental and public health measures to control disease spread, infections continue at an unabated pace, suggesting that effective vaccines and antiviral drugs will be required to curtail disease, end the pandemic, and restore societal norms. Here, we review the current developments in antibody and vaccine countermeasures to limit or prevent disease.


Assuntos
Anticorpos Antivirais/biossíntese , /prevenção & controle , Pandemias , /imunologia , Animais , /imunologia , /virologia , /biossíntese , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Vetores Genéticos/química , Vetores Genéticos/imunologia , Humanos , Imunidade Inata/efeitos dos fármacos , Imunização Passiva/métodos , Imunogenicidade da Vacina , Segurança do Paciente , /patogenicidade , Vacinas Atenuadas , Vacinas de DNA , Vacinas de Subunidades , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Vacinas de Partículas Semelhantes a Vírus/biossíntese , Vacinas de Partículas Semelhantes a Vírus/imunologia
2.
J Nanobiotechnology ; 19(1): 59, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33632278

RESUMO

Virus-like particles (VLPs) are virus-derived structures made up of one or more different molecules with the ability to self-assemble, mimicking the form and size of a virus particle but lacking the genetic material so they are not capable of infecting the host cell. Expression and self-assembly of the viral structural proteins can take place in various living or cell-free expression systems after which the viral structures can be assembled and reconstructed. VLPs are gaining in popularity in the field of preventive medicine and to date, a wide range of VLP-based candidate vaccines have been developed for immunization against various infectious agents, the latest of which is the vaccine against SARS-CoV-2, the efficacy of which is being evaluated. VLPs are highly immunogenic and are able to elicit both the antibody- and cell-mediated immune responses by pathways different from those elicited by conventional inactivated viral vaccines. However, there are still many challenges to this surface display system that need to be addressed in the future. VLPs that are classified as subunit vaccines are subdivided into enveloped and non- enveloped subtypes both of which are discussed in this review article. VLPs have also recently received attention for their successful applications in targeted drug delivery and for use in gene therapy. The development of more effective and targeted forms of VLP by modification of the surface of the particles in such a way that they can be introduced into specific cells or tissues or increase their half-life in the host is likely to expand their use in the future. Recent advances in the production and fabrication of VLPs including the exploration of different types of expression systems for their development, as well as their applications as vaccines in the prevention of infectious diseases and cancers resulting from their interaction with, and mechanism of activation of, the humoral and cellular immune systems are discussed in this review.


Assuntos
/uso terapêutico , Anticorpos Neutralizantes/imunologia , /imunologia , Humanos , Imunidade/fisiologia , /patogenicidade , Vacinação/métodos , Vacinas de Partículas Semelhantes a Vírus/biossíntese , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas de Partículas Semelhantes a Vírus/uso terapêutico
3.
Methods Mol Biol ; 2183: 183-203, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32959245

RESUMO

Zika virus (ZIKV) is a mosquito-transmitted virus that has caused major outbreaks of disease around the world over the last few years. The infectious ZIKV consists of a structural protein outer shell surrounding a nucleocapsid. Virus-like particles (VLP) consist of the outer structural protein shell, but without the nucleocapsid, and are hence noninfectious. VLP, however, are structurally equivalent to the native virus and thus present a similar antigenic profile. These properties make them good candidates for vaccine development. ZIKV VLP can be generated on a laboratory scale by cloning the relevant structural proteins into a eukaryotic expression vector and transfecting the construct into mammalian cells. The secreted VLP can be harvested from the culture medium and purified by sucrose cushion ultracentrifugation. Validation of the VLP is achieved through western blotting and electron microscopy.


Assuntos
Técnicas de Cultura Celular por Lotes , Vacinas de Partículas Semelhantes a Vírus/biossíntese , Vacinas de Partículas Semelhantes a Vírus/imunologia , Zika virus/imunologia , Técnicas de Cultura de Células , Clonagem Molecular , Expressão Gênica , Engenharia Genética , Vetores Genéticos/genética , Células HEK293 , Humanos , Plasmídeos/genética , Vacinas de Partículas Semelhantes a Vírus/isolamento & purificação , Vacinas de Partículas Semelhantes a Vírus/ultraestrutura
4.
Methods Mol Biol ; 2183: 205-215, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32959246

RESUMO

The outermost surface of bacterial pathogens consists primarily of complex carbohydrate structures-polysaccharides, glycolipids, and glycoproteins. To raise a long-lasting and effective immune response against carbohydrate antigens, they generally require covalent attachment to an immunogenic carrier protein-a so-called glycoconjugate vaccine. One hurdle to the development of glycoconjugate vaccines is that carbohydrate antigens remain inaccessible to recombinant production. Thus, the carbohydrate antigen is typically purified from the pathogen and then chemically conjugated to an immunogenic protein. Recent developments in the field of bacterial glycoengineering have opened the opportunity for total recombinant production of glycoconjugate vaccines. In this method, we describe the production of proteinaceous, virus-like particles (VLPs) bearing the conserved N-glycan of Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumoniae.


Assuntos
Vacinas Conjugadas/biossíntese , Vacinas Conjugadas/imunologia , Vacinas de Partículas Semelhantes a Vírus/biossíntese , Vacinas de Partículas Semelhantes a Vírus/imunologia , Antígenos/imunologia , Escherichia coli , Glicoproteínas/imunologia , Proteínas Recombinantes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Vacinas Conjugadas/isolamento & purificação , Vacinas de Partículas Semelhantes a Vírus/isolamento & purificação , Vacinas de Partículas Semelhantes a Vírus/ultraestrutura
5.
Methods Mol Biol ; 2183: 217-248, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32959247

RESUMO

The increasing medical interest in viral nanoplexes, such as viruses or virus-like particles used for vaccines, gene therapy products, or oncolytic agents, raises the need for fast and efficient production processes. In general, these processes comprise upstream and downstream processing. For the upstream process, efficiency is mainly characterized by robustly achieving high titer yields, while reducing process times and costs with regard to the cell culture medium, the host cell selection, and the applied process conditions. The downstream part, on the other hand, should effectively remove process-related contaminants, such as host cells/cell debris as well as host cell DNA and proteins, while maintaining product stability and reducing product losses. This chapter outlines a combination of process steps to successfully produce virus particles in the controlled environment of a stirred tank bioreactor, combined with a platform-based purification approach using filtration-based clarification and steric exclusion chromatography. Additionally, suggestions for off-line analytics in terms of virus characterization and quantification as well as for contaminant estimation are provided.


Assuntos
Reatores Biológicos , Nanocompostos , Vacinologia/métodos , Vacinas Virais/biossíntese , Vacinas Virais/isolamento & purificação , Animais , Técnicas de Cultura de Células , Humanos , Vacinas de Partículas Semelhantes a Vírus/biossíntese , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas de Partículas Semelhantes a Vírus/isolamento & purificação , Vacinas Virais/imunologia , Vírion/isolamento & purificação
6.
Methods Mol Biol ; 2248: 139-153, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33185873

RESUMO

Virus-like particle (VLP) technology is an alternative platform for developing vaccines to combat seasonal and pandemic influenza. Influenza VLPs are non-infectious nanoparticles that can elicit effective vaccine immunogenicity in hosts. B-cell-activating factor (BAFF, or BLyS) and a proliferation-inducing ligand (APRIL) are members of the tumor necrosis factor (TNF) superfamily of cytokines. Both BAFF and APRIL are homotrimers that interact with homotrimeric receptors. Here, we report a method of the production of influenza VLPs by molecular incorporation with BAFF or APRIL homotrimers to interact with their receptors. We engineered the VLPs by direct fusion of BAFF or APRIL to the transmembrane anchored domain of the hemagglutinin (HA) gene. We also describe procedures for the production of BAFF-VLPs containing H5H7 and H1H5H7 for multi-subtype vaccine development.


Assuntos
Antígenos Virais/imunologia , Fator Ativador de Células B/imunologia , Vacinas contra Influenza/imunologia , Proteínas Recombinantes de Fusão , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Animais , Antígenos Virais/genética , Fator Ativador de Células B/genética , Baculoviridae/genética , Clonagem Molecular , Expressão Gênica , Testes de Hemaglutinação , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Virus da Influenza A Subtipo H5N1/imunologia , Plasmídeos/genética , Proteínas Recombinantes de Fusão/imunologia , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética
7.
Viruses ; 12(12)2020 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-33339324

RESUMO

Baculovirus expression vectors are successfully used for the commercial production of complex (glyco)proteins in eukaryotic cells. The genome engineering of single-copy baculovirus infectious clones (bacmids) in E. coli has been valuable in the study of baculovirus biology, but bacmids are not yet widely applied as expression vectors. An important limitation of first-generation bacmids for large-scale protein production is the rapid loss of gene of interest (GOI) expression. The instability is caused by the mini-F replicon in the bacmid backbone, which is non-essential for baculovirus replication in insect cells, and carries the adjacent GOI in between attTn7 transposition sites. In this paper, we test the hypothesis that relocation of the attTn7 transgene insertion site away from the mini-F replicon prevents deletion of the GOI, thereby resulting in higher and prolonged recombinant protein expression levels. We applied lambda red genome engineering combined with SacB counterselection to generate a series of bacmids with relocated attTn7 sites and tested their performance by comparing the relative expression levels of different GOIs. We conclude that GOI expression from the odv-e56 (pif-5) locus results in higher overall expression levels and is more stable over serial passages compared to the original bacmid. Finally, we evaluated this improved next-generation bacmid during a bioreactor scale-up of Sf9 insect cells in suspension to produce enveloped chikungunya virus-like particles as a model vaccine.


Assuntos
Baculoviridae/genética , Genoma Viral , Instabilidade Genômica , Recombinação Homóloga , Mutagênese Insercional , Proteínas Recombinantes/genética , Transgenes , Animais , Reatores Biológicos , Linhagem Celular , Vírus Chikungunya/imunologia , Engenharia Genética , Vetores Genéticos/genética , Insetos , Células Sf9 , Vacinas de Partículas Semelhantes a Vírus/imunologia
8.
Arch Virol ; 165(12): 2829-2835, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33000310

RESUMO

The swine pathogen porcine circovirus type 2 (PCV2) causes significant economic damage worldwide. The PCV2 capsid (CP) residues 169-STIDYFQPNNKR-180 have been identified as a decoy epitope that diverts the host immune response away from protective epitopes. However, the decoy epitope may include important linear or conformational protective epitopes against PCV2. In this study, we used the baculovirus system to express recombinant complete CP (1-233) and mutant CP (Δ169-180), in which the decoy epitope was deleted, and evaluated the immune response to these in mice. Immunization with mutant CP (Δ169-180) protein, which formed very low level of virus-like particles (VLPs), elicited significantly lower levels of PCV2 CP-specific IgG antibodies and a slightly lower neutralizing activity than immunization with the complete CP (1-233) protein. This finding suggests that the complete CP is important for efficient VLP assembly and induction of PCV2-specific IgG antibodies and neutralizing antibodies in mice. This study may provide useful information for next-generation vaccine design for PCV2 control.


Assuntos
Proteínas do Capsídeo/imunologia , Circovirus/imunologia , Epitopos/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Animais , Anticorpos Neutralizantes/análise , Anticorpos Antivirais/análise , Proteínas do Capsídeo/biossíntese , Proteínas do Capsídeo/genética , Circovirus/genética , Epitopos/biossíntese , Epitopos/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Síndrome Definhante Multissistêmico de Suínos Desmamados/imunologia , Síndrome Definhante Multissistêmico de Suínos Desmamados/prevenção & controle , Suínos , Vacinação , Vacinas de Partículas Semelhantes a Vírus/genética
9.
Front Immunol ; 11: 583077, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33101309

RESUMO

Despite the success of vaccination to greatly mitigate or eliminate threat of diseases caused by pathogens, there are still known diseases and emerging pathogens for which the development of successful vaccines against them is inherently difficult. In addition, vaccine development for people with compromised immunity and other pre-existing medical conditions has remained a major challenge. Besides the traditional inactivated or live attenuated, virus-vectored and subunit vaccines, emerging non-viral vaccine technologies, such as viral-like particle and nanoparticle vaccines, DNA/RNA vaccines, and rational vaccine design, offer innovative approaches to address existing challenges of vaccine development. They have also significantly advanced our understanding of vaccine immunology and can guide future vaccine development for many diseases, including rapidly emerging infectious diseases, such as COVID-19, and diseases that have not traditionally been addressed by vaccination, such as cancers and substance abuse. This review provides an integrative discussion of new non-viral vaccine development technologies and their use to address the most fundamental and ongoing challenges of vaccine development.


Assuntos
Betacoronavirus/imunologia , Doenças Transmissíveis Emergentes/prevenção & controle , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Doenças Transmissíveis Emergentes/virologia , Infecções por Coronavirus/imunologia , Nanopartículas , Vacinação , Vacinas de DNA/imunologia , Vacinas de Subunidades/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia
10.
Virus Res ; 288: 198114, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32800805

RESUMO

The current COVID-19 pandemic has urged the scientific community internationally to find answers in terms of therapeutics and vaccines to control SARS-CoV-2. Published investigations mostly on SARS-CoV and to some extent on MERS has taught lessons on vaccination strategies to this novel coronavirus. This is attributed to the fact that SARS-CoV-2 uses the same receptor as SARS-CoV on the host cell i.e. human Angiotensin Converting Enzyme 2 (hACE2) and is approximately 79% similar genetically to SARS-CoV. Though the efforts on COVID-19 vaccines started very early, initially in China, as soon as the outbreak of novel coronavirus erupted and then world-over as the disease was declared a pandemic by WHO. But we will not be having an effective COVID-19 vaccine before September, 2020 as per very optimistic estimates. This is because a successful COVID-19 vaccine will require a cautious validation of efficacy and adverse reactivity as the target vaccinee population include high-risk individuals over the age of 60, particularly those with chronic co-morbid conditions, frontline healthcare workers and those involved in essentials industries. Various platforms for vaccine development are available namely: virus vectored vaccines, protein subunit vaccines, genetic vaccines, and monoclonal antibodies for passive immunization which are under evaluations for SARS-CoV-2, with each having discrete benefits and hindrances. The COVID-19 pandemic which probably is the most devastating one in the last 100 years after Spanish flu mandates the speedy evaluation of the multiple approaches for competence to elicit protective immunity and safety to curtail unwanted immune-potentiation which plays an important role in the pathogenesis of this virus. This review is aimed at providing an overview of the efforts dedicated to an effective vaccine for this novel coronavirus which has crippled the world in terms of economy, human health and life.


Assuntos
Anticorpos Antivirais/biossíntese , Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/patogenicidade , Ensaios Clínicos como Assunto , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Infecções por Coronavirus/virologia , Vetores Genéticos/química , Vetores Genéticos/imunologia , Humanos , Imunidade Inata/efeitos dos fármacos , Imunização Passiva/métodos , Imunogenicidade da Vacina , Segurança do Paciente , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/imunologia , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Receptores Virais/genética , Receptores Virais/imunologia , Receptores Virais/metabolismo , Vacinas Atenuadas , Vacinas de DNA , Vacinas de Subunidades , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Vacinas de Partículas Semelhantes a Vírus/biossíntese , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/biossíntese
11.
Sheng Wu Gong Cheng Xue Bao ; 36(7): 1440-1449, 2020 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-32748602

RESUMO

Hepatitis B virus core protein can self-assemble into icosahedral symmetrical viral-like particles (VLPs) in vitro, and display exogenous sequences repeatedly and densely on the surface. VLPs also have strong immunogenicity and biological activity. When the nanoparticles enter the body, they quickly induce specific humoral and cellular immune responses to exogenous antigens. In this study, we designed an HBc-VLPs that can be coupled with antigens at specific sites, and developed a set of efficient methods to prepare HBc-VLPs. Through site-specific mutation technology, the 80th amino acid of peptide was changed from Ala to Cys, a specific cross-linking site was inserted into the main immunodominant region of HBc-VLPs, and the prokaryotic expression vector pET28a(+)-hbc was constructed. After expression and purification, high purity HBc(A80C) monomer protein was assembled into HBc-VLPs nanoparticles in Phosphate Buffer. The results of particle size analysis show that the average particle size of nanoparticles was 29.8 nm. Transmission electron microscopy (TEM) showed that HBc-VLPs formed spherical particles with a particle size of about 30 nm, and its morphology was similar to that of natural HBV particles. The influenza virus antigen M2e peptide as model antigen was connected to Cys residue of HBc-VLPs by Sulfo-SMCC, an amino sulfhydryl bifunctional cross-linking agent, and M2e-HBc-VLPs model vaccine was prepared. The integrity of HBc-VLPs structure and the correct cross-linking of M2e were verified by cell fluorescence tracing. Animal immune experiments showed that the vaccine can effectively stimulate the production of antigen-specific IgG antibody in mice, which verified the effectiveness of the vaccine carrier HBc-VLPs. This study lays a foundation for the research of HBc-VLPs as vaccine vector, and help to promote the development of HBc-VLPs vaccine and the application of HBc-VLPs in other fields.


Assuntos
Antígenos do Núcleo do Vírus da Hepatite B , Imunidade Celular , Vacinas de Partículas Semelhantes a Vírus , Animais , Antígenos do Núcleo do Vírus da Hepatite B/genética , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Imunidade Celular/imunologia , Imunoglobulina G/sangue , Camundongos , Camundongos Endogâmicos BALB C , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas de Partículas Semelhantes a Vírus/imunologia
12.
Virus Res ; 288: 198141, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32846196

RESUMO

The recent outbreak of the betacoronavirus SARS-CoV-2 has become a significant concern to public health care worldwide. As of August 19, 2020, more than 22,140,472 people are infected, and over 781,135 people have died due to this deadly virus. In the USA alone, over 5,482,602 people are currently infected, and more than 171,823 people have died. SARS-CoV-2 has shown a higher infectivity rate and a more extended incubation period as compared to previous coronaviruses. SARS-CoV-2 binds much more strongly than SARS-CoV to the same host receptor, angiotensin-converting enzyme 2 (ACE2). Previously, several methods to develop a vaccine against SARS-CoV or MERS-CoV have been tried with limited success. Since SARS-CoV-2 uses the spike (S) protein for entry to the host cell, it is one of the most preferred targets for making vaccines or therapeutics against SARS-CoV-2. In this review, we have summarised the characteristics of the S protein, as well as the different approaches being used for the development of vaccines and/or therapeutics based on the S protein.


Assuntos
Anticorpos Antivirais/biossíntese , Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , Anticorpos Facilitadores/efeitos dos fármacos , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/patogenicidade , Ensaios Clínicos como Assunto , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Vetores Genéticos/química , Vetores Genéticos/imunologia , Humanos , Imunogenicidade da Vacina , Segurança do Paciente , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/imunologia , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Receptores Virais/genética , Receptores Virais/imunologia , Receptores Virais/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Vacinas Atenuadas , Vacinas de DNA , Vacinas de Subunidades , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Vacinas de Partículas Semelhantes a Vírus/biossíntese , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/biossíntese
13.
Vaccine ; 38(36): 5742-5746, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32684497

RESUMO

Recent advances in virus-like nanoparticles against Middle East respiratory syndrome-related coronavirus (MERS-CoV) can initiate vaccine production faster for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), while ensuring the safety, easy administration, and long-term effects. Patients with this viral pathogen suffer from excess mortality. MERS-CoV can spread through bioaerosol transmission from animal or human sources. The appearance of an outbreak in South Korea sparked off a strong urge to design strategies for developing an effective vaccine since the emergence of MERS-CoV in 2012. Well unfortunately, this is an important fact in virus risk management. The studies showed that virus-like nanoparticles (VLPs) could be effective in its goal of stopping the symptoms of MERS-CoV infection. Besides, due to the genetic similarities in the DNA sequencing of SARS-CoV-2 with MERS-CoV and the first identified severe acute respiratory syndrome (SARS-CoV) in China since 2002/2003, strategic approaches could be used to manage SARS-CoV 2. Gathering the vital piece of information obtained so far could lead to a breakthrough in the development of an effective vaccine against SARS-CoV-2, which is prioritized and focussed by the World Health Organization (WHO). This review focuses on the virus-like nanoparticle that got successful results in animal models of MERS-CoV.


Assuntos
Infecções por Coronavirus/prevenção & controle , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Animais , Betacoronavirus/imunologia , Avaliação Pré-Clínica de Medicamentos , Humanos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas de Partículas Semelhantes a Vírus/isolamento & purificação
14.
Nat Commun ; 11(1): 2841, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503989

RESUMO

The capsid of human papillomavirus (HPV) spontaneously arranges into a T = 7 icosahedral particle with 72 L1 pentameric capsomeres associating via disulfide bonds between Cys175 and Cys428. Here, we design a capsomere-hybrid virus-like particle (chVLP) to accommodate multiple types of L1 pentamers by the reciprocal assembly of single C175A and C428A L1 mutants, either of which alone encumbers L1 pentamer particle self-assembly. We show that co-assembly between any pair of C175A and C428A mutants across at least nine HPV genotypes occurs at a preferred equal molar stoichiometry, irrespective of the type or number of L1 sequences. A nine-valent chVLP vaccine-formed through the structural clustering of HPV epitopes-confers neutralization titers that are comparable with that of Gardasil 9 and elicits minor cross-neutralizing antibodies against some heterologous HPV types. These findings may pave the way for a new vaccine design that targets multiple pathogenic variants or cancer cells bearing diverse neoantigens.


Assuntos
Proteínas do Capsídeo/imunologia , Neoplasias/terapia , Papillomaviridae/imunologia , Infecções por Papillomavirus/terapia , Vacinas contra Papillomavirus/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Proteínas do Capsídeo/administração & dosagem , Proteínas do Capsídeo/genética , Desenho de Fármacos , Epitopos/genética , Epitopos/imunologia , Feminino , Humanos , Imunogenicidade da Vacina , Camundongos , Modelos Animais , Mutação , Neoplasias/virologia , Testes de Neutralização , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Vacinas contra Papillomavirus/administração & dosagem , Vacinas contra Papillomavirus/genética , Multimerização Proteica/genética , Multimerização Proteica/imunologia , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas de Partículas Semelhantes a Vírus/imunologia
15.
Cell Mol Life Sci ; 77(21): 4315-4324, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32367191

RESUMO

Epstein-Barr virus (EBV) was the first human tumor virus being discovered and remains to date the only human pathogen that can transform cells in vitro. 55 years of EBV research have now brought us to the brink of an EBV vaccine. For this purpose, recombinant viral vectors and their heterologous prime-boost vaccinations, EBV-derived virus-like particles and viral envelope glycoprotein formulations are explored and are discussed in this review. Even so, cell-mediated immune control by cytotoxic lymphocytes protects healthy virus carriers from EBV-associated malignancies, antibodies might be able to prevent symptomatic primary infection, the most likely EBV-associated pathology against which EBV vaccines will be initially tested. Thus, the variety of EBV vaccines reflects the sophisticated life cycle of this human tumor virus and only vaccination in humans will finally be able to reveal the efficacy of these candidates. Nevertheless, the recently renewed efforts to develop an EBV vaccine and the long history of safe adoptive T cell transfer to treat EBV-associated malignancies suggest that this oncogenic γ-herpesvirus can be targeted by immunotherapies. Such vaccination should ideally implement the very same immune control that protects healthy EBV carriers.


Assuntos
Infecções por Vírus Epstein-Barr/prevenção & controle , Herpesvirus Humano 4/imunologia , Vacinas contra Herpesvirus/uso terapêutico , Animais , Anticorpos Neutralizantes/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Vacinas contra Herpesvirus/imunologia , Humanos , Vacinação , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas de Partículas Semelhantes a Vírus/uso terapêutico , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/uso terapêutico
16.
Int J Nanomedicine ; 15: 1983-1996, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32308382

RESUMO

Background: Fibroblast growth factor (FGF)-2 is overexpressed in various tumor tissues. It affects tumor cell proliferation, invasion and survival, promotes tumor angiogenesis and is tightly involved in the development of systemic and local immunosuppressive tumor mechanisms. Purpose: This study aimed to develop an effective vaccine against FGF-2 and to investigate the effects of anti-FGF-2 immunization on tumor growth and antitumor immune responses. Methods: A set of thirteen synthesized overlapping peptides covering all possible linear B-cell epitopes of murine FGF-2 and a recombinant FGF-2 protein were conjugated to virus-like particles (VLPs) of recombinant hepatitis B core antigen (HBcAg). The VLPs were immunized through a preventive or therapeutic strategy in a TC-1 or 4T1 grafted tumor model. Results: Immunization with FGF-2 peptides or full-length protein-coupled VLPs produced FGF-2-specific antibodies with a high titer. Peptide 12, which is located in the heparin-binding site of FGF-2, or protein-conjugated VLPs presented the most significant effects on the suppression of TC-1 tumor growth. The levels of IFN-γ-expressing splenocytes and serum IFN-γ were significantly elevated; further, the immune effector cells CD8+ IFN-γ+ cytotoxic T lymphocytes (CTLs) and CD4+ IFN-γ+ Th1 cells were significantly increased, whereas the immunosuppressive cells CD4+ CD25+ FOXP3+ Treg cells and Gr-1+ CD11b+ myeloid-derived suppressor cells (MDSCs) were decreased in the immunized mice. In addition, VLP immunization significantly suppressed tumor vascularization and promoted tumor cell apoptosis. In mice bearing 4T1 breast tumor, preventive immunization with FGF-2-conjugated VLPs suppressed tumor growth and lung metastasis, and increased effector cell responses. Conclusion: Active immunization against FGF-2 is a new possible strategy for tumor immunotherapy.


Assuntos
Vacinas Anticâncer/farmacologia , Epitopos de Linfócito B/imunologia , Fator 2 de Crescimento de Fibroblastos/imunologia , Peptídeos/imunologia , Vacinas de Partículas Semelhantes a Vírus/farmacologia , Animais , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Feminino , Antígenos do Núcleo do Vírus da Hepatite B/genética , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/imunologia , Imunoterapia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/terapia , Neovascularização Patológica/tratamento farmacológico , Peptídeos/genética , Linfócitos T Citotóxicos/imunologia , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Vacinação , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas de Partículas Semelhantes a Vírus/imunologia
17.
Arch Virol ; 165(6): 1441-1444, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32239294

RESUMO

Bovine papillomavirus type 9 (BPV9) is a causative agent of severe teat papillomatosis. Considering the lack of efficient BPV culture methods, recombinant proteins such as virus-like particles developed through genetic engineering may serve as a useful tool for developing effective vaccines against BPV infection. In this study, we successfully produced immunogenic particles composed of recombinant L1 protein of BPV9 (rBPV9-L1), using a baculovirus expression system. rBPV9-L1-immunized mice produced BPV9-specific IgG, which did not cross-react with BPV type 6, which is another causative agent of teat papillomatosis. Hence, immunogenic rBPV9-L1 is potentially applicable as a vaccine candidate for teat papillomatosis.


Assuntos
Proteínas do Capsídeo/imunologia , Doenças dos Bovinos/prevenção & controle , Papillomaviridae/imunologia , Infecções por Papillomavirus/veterinária , Vacinas de Partículas Semelhantes a Vírus/imunologia , Animais , Proteínas do Capsídeo/biossíntese , Bovinos , Doenças dos Bovinos/virologia , Feminino , Genótipo , Camundongos , Papillomaviridae/genética , Infecções por Papillomavirus/prevenção & controle , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Vacinação
19.
JAMA ; 323(14): 1369-1377, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286643

RESUMO

Importance: Chikungunya virus (CHIKV) is a mosquito-borne Alphavirus prevalent worldwide. There are currently no licensed vaccines or therapies. Objective: To evaluate the safety and tolerability of an investigational CHIKV virus-like particle (VLP) vaccine in endemic regions. Design, Setting, and Participants: This was a randomized, placebo-controlled, double-blind, phase 2 clinical trial to assess the vaccine VRC-CHKVLP059-00-VP (CHIKV VLP). The trial was conducted at 6 outpatient clinical research sites located in Haiti, Dominican Republic, Martinique, Guadeloupe, and Puerto Rico. A total of 400 healthy adults aged 18 through 60 years were enrolled after meeting eligibility criteria. The first study enrollment occurred on November 18, 2015; the final study visit, March 6, 2018. Interventions: Participants were randomized 1:1 to receive 2 intramuscular injections 28 days apart (20 µg, n = 201) or placebo (n = 199) and were followed up for 72 weeks. Main Outcomes and Measures: The primary outcome was the safety (laboratory parameters, adverse events, and CHIKV infection) and tolerability (local and systemic reactogenicity) of the vaccine, and the secondary outcome was immune response by neutralization assay 4 weeks after second vaccination. Results: Of the 400 randomized participants (mean age, 35 years; 199 [50%] women), 393 (98%) completed the primary safety analysis. All injections were well tolerated. Of the 16 serious adverse events unrelated to the study drugs, 4 (25%) occurred among 4 patients in the vaccine group and 12 (75%) occurred among 11 patients in the placebo group. Of the 16 mild to moderate unsolicited adverse events that were potentially related to the drug, 12 (75%) occurred among 8 patients in the vaccine group and 4 (25%) occurred among 3 patients in the placebo group. All potentially related adverse events resolved without clinical sequelae. At baseline, there was no significant difference between the effective concentration (EC50)-which is the dilution of sera that inhibits 50% infection in viral neutralization assay-geometric mean titers (GMTs) of neutralizing antibodies of the vaccine group (46; 95% CI, 34-63) and the placebo group (43; 95% CI, 32-57). Eight weeks following the first administration, the EC50 GMT in the vaccine group was 2005 (95% CI, 1680-2392) vs 43 (95% CI, 32-58; P < .001) in the placebo group. Durability of the immune response was demonstrated through 72 weeks after vaccination. Conclusions and Relevance: Among healthy adults in a chikungunya endemic population, a virus-like particle vaccine compared with placebo demonstrated safety and tolerability. Phase 3 trials are needed to assess clinical efficacy. Trial Registration: ClinicalTrials.gov Identifier: NCT02562482.


Assuntos
Febre de Chikungunya/prevenção & controle , Vírus Chikungunya/imunologia , Vacinas de Partículas Semelhantes a Vírus/efeitos adversos , Vacinas Virais/efeitos adversos , Adolescente , Adulto , Anticorpos Neutralizantes/sangue , Febre de Chikungunya/imunologia , Método Duplo-Cego , Feminino , Humanos , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia , Adulto Jovem
20.
Parasite Immunol ; 42(6): e12716, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32249951

RESUMO

AIMS: Neuroinflammation can manifest upon infection with the neurotropic parasite Toxoplasma gondii (ME49), which can lead to brain injury and cognitive dysfunction. Rhoptry organelle proteins (ROPs) secreted by T gondii play critical roles in host invasion. METHODS AND RESULTS: In this study, influenza virus-like particles (VLPs) expressing T gondii ROP4 or ROP13 were generated to assess vaccination-induced changes in intracranial pro-inflammatory cytokines and antibody responses upon T gondii challenge infection. Compared to ROP13 VLPs, ROP4VLPs vaccination significantly limited the production of pro-inflammatory cytokines IFN-γ and IL-6 in the brains of mice. Reduced pro-inflammatory cytokine responses by ROP4 VLPs and ROP13 VLPs correlated with significantly increased T gondii-specific IgG and IgA antibody responses in the brain, as well as IgG, IgG1 and IgM antibody responses in the sera. CONCLUSION: We concluded that influenza T gondii VLP vaccination induces antibody responses in sera and brain, which may contribute to the significant reduction of neuroinflammation during T gondii infection.


Assuntos
Anticorpos Antiprotozoários/sangue , Encéfalo/imunologia , Proteínas de Membrana/imunologia , Proteínas de Protozoários/imunologia , Toxoplasma/imunologia , Vacinação , Vacinas de Partículas Semelhantes a Vírus/imunologia , Animais , Encéfalo/parasitologia , Linhagem Celular , Feminino , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Inflamação/imunologia , Interferon gama/imunologia , Interleucina-6/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Células Sf9
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