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1.
Microb Pathog ; 190: 106630, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38556102

RESUMO

Porcine circovirus type 2 (PCV2) is a globally prevalent infectious pathogen affecting swine, with its capsid protein (Cap) being the sole structural protein critical for vaccine development. Prior research has demonstrated that PCV2 Cap proteins produced in Escherichia coli (E. coli) can form virus-like particles (VLPs) in vitro, and nuclear localization signal peptides (NLS) play a pivotal role in stabilizing PCV2 VLPs. Recently, PCV2d has emerged as an important strain within the PCV2 epidemic. In this study, we systematically optimized the PCV2d Cap protein and successfully produced intact PCV2d VLPs containing NLS using E. coli. The recombinant PCV2d Cap protein was purified through affinity chromatography, yielding 7.5 mg of recombinant protein per 100 ml of bacterial culture. We augmented the conventional buffer system with various substances such as arginine, ß-mercaptoethanol, glycerol, polyethylene glycol, and glutathione to promote VLP assembly. The recombinant PCV2d Cap self-assembled into VLPs approximately 20 nm in diameter, featuring uniform distribution and exceptional stability in the optimized buffer. We developed the vaccine and immunized pigs and mice, evaluating the immunogenicity of the PCV2d VLPs vaccine by measuring PCV2-IgG, IL-4, TNF-α, and IFN-γ levels, comparing them to commercial vaccines utilizing truncated PCV2 Cap antigens. The HE staining and immunohistochemical tests confirmed that the PCV2 VLPs vaccine offered robust protection. The results revealed that animals vaccinated with the PCV2d VLPs vaccine exhibited high levels of PCV2 antibodies, with TNF-α and IFN-γ levels rapidly increasing at 14 days post-immunization, which were higher than those observed in commercially available vaccines, particularly in the mouse trial. This could be due to the fact that full-length Cap proteins can assemble into more stable PCV2d VLPs in the assembling buffer. In conclusion, our produced PCV2d VLPs vaccine elicited stronger immune responses in pigs and mice compared to commercial vaccines. The PCV2d VLPs from this study serve as an excellent candidate vaccine antigen, providing insights for PCV2d vaccine research.


Assuntos
Anticorpos Antivirais , Proteínas do Capsídeo , Circovirus , Escherichia coli , Proteínas Recombinantes , Vacinas de Partículas Semelhantes a Vírus , Animais , Circovirus/imunologia , Circovirus/genética , Suínos , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas de Partículas Semelhantes a Vírus/genética , Proteínas do Capsídeo/imunologia , Proteínas do Capsídeo/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Camundongos , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/genética , Infecções por Circoviridae/prevenção & controle , Infecções por Circoviridae/imunologia , Doenças dos Suínos/prevenção & controle , Vacinas Virais/imunologia , Vacinas Virais/genética , Desenvolvimento de Vacinas , Antígenos Virais/imunologia , Antígenos Virais/genética , Imunoglobulina G/sangue , Análise Custo-Benefício , Feminino , Interferon gama/metabolismo , Imunogenicidade da Vacina
2.
Arch Razi Inst ; 78(3): 997-1003, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-38028838

RESUMO

Today, the human papillomavirus (HPV) L1 protein is the main target in the construction of prophylactic HPV vaccines. The production of virus-like particles (VLPs) that closely resemble the natural structure of the HPV16 virus and induce high levels of virus-neutralizing antibodies in animals and humans is facilitated by the expression of HPV16-L1 protein in eukaryotic cells. The Bac-to-Bac system has been previously used to produce high levels of recombinant proteins. In this study, we utilized this expression system to generate HPV16-L1 VLPs in Spodoptra frugipedra (Sf9) insect cells. The wild-type L1 gene of papillomavirus type 16 was selected from Gene Bank and placed in bacmid structure after codon optimization using pFast Bac vector. The recombinant baculovirus containing HPV-16/L1 gene was then provided using the Bac-to-Bac system. It should be mentioned that the vector was transfected into the Sf9 cell. The cells were then lysed and the expression of L1 protein was revealed by SDS-PAGE and confirmed by Western Blot. The L1 purification was performed through Ni-NTA chromatography. The VLP formation of papillomavirus L1 protein was visualized by transmission electron microscopy. The expressed recombinant L1 was ~60 KD on SDS-PAGE which was identified in western blot by a specific anti-L1 monoclonal antibody. The electron microscopy confirmed the assembly of VLPs. Results of this study showed that the production of this protein at the industrial level can be optimized using a baculovirus/Sf9 system. The characteristics and advantages of this system are promising and it is a suitable candidate for protein synthesis.


Assuntos
Infecções por Papillomavirus , Vacinas de Partículas Semelhantes a Vírus , Animais , Humanos , Papillomavirus Humano 16/genética , Vacinas de Partículas Semelhantes a Vírus/genética , Proteínas Recombinantes/genética , Microscopia Eletrônica , Baculoviridae
3.
Front Cell Infect Microbiol ; 13: 1216364, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37424789

RESUMO

Introduction: Virus-like particles (VLPs) are similar in size and shape to their respective viruses, but free of viral genetic material. This makes VLP-based vaccines incapable of causing infection, but still effective in mounting immune responses. Noro-VLPs consist of 180 copies of the VP1 capsid protein. The particle tolerates C-terminal fusion partners, and VP1 fused with a C-terminal SpyTag self-assembles into a VLP with SpyTag protruding from its surface, enabling conjugation of antigens via SpyCatcher. Methods: To compare SpyCatcher-mediated coupling and direct peptide fusion in experimental vaccination, we genetically fused the ectodomain of influenza matrix-2 protein (M2e) directly on the C-terminus of norovirus VP1 capsid protein. VLPs decorated with SpyCatcher-M2e and VLPs with direct M2 efusion were used to immunize mice. Results and discussion: We found that direct genetic fusion of M2e on noro-VLP raised few M2e antibodies in the mouse model, presumably because the short linker positions the peptide between the protruding domains of noro-VLP, limiting its accessibility. On the other hand, adding aluminum hydroxide adjuvant to the previously described SpyCatcher-M2e-decorated noro-VLP vaccine gave a strong response against M2e. Surprisingly, simple SpyCatcher-fused M2e without VLP display also functioned as a potent immunogen, which suggests that the commonly used protein linker SpyCatcher-SpyTag may serve a second role as an activator of the immune system in vaccine preparations. Based on the measured anti-M2e antibodies and cellular responses, both SpyCatcher-M2e as well as M2e presented on the noro-VLP via SpyTag/Catcher show potential for the development of universal influenza vaccines.


Assuntos
Vacinas contra Influenza , Influenza Humana , Norovirus , Vacinas de Partículas Semelhantes a Vírus , Animais , Camundongos , Humanos , Vacinas contra Influenza/genética , Proteínas do Capsídeo/genética , Norovirus/genética , Imunização , Vacinação , Peptídeos/genética , Camundongos Endogâmicos BALB C , Anticorpos Antivirais , Vacinas de Partículas Semelhantes a Vírus/genética
4.
Small ; 19(23): e2300125, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36879481

RESUMO

The widespread preexisting immunity against virus-like particles (VLPs) seriously limits the applications of VLPs as vaccine vectors. Enabling technology for exogenous antigen display should not only ensure the assembly ability of VLPs and site-specific modification, but also consider the effect of preexisting immunity on the behavior of VLPs in vivo. Here, combining genetic code expansion technique and synthetic biology strategy, a site-specific modification method for hepatitis B core (HBc) VLPs via incorporating azido-phenylalanine into the desired positions is described. Through modification position screening, it is found that HBc VLPs incorporated with azido-phenylalanine at the main immune region can effectively assemble and rapidly conjugate with the dibenzocycolctyne-modified tumor-associated antigens, mucin-1 (MUC1). The site-specific modification of HBc VLPs not only improves the immunogenicity of MUC1 antigens but also shields the immunogenicity of HBc VLPs themselves, thereby activating a strong and persistent anti-MUC1 immune response even in the presence of preexisting anti-HBc immunity, which results in the efficient tumor elimination in a lung metastatic mouse model. Together, these results demonstrate the site-specific modification strategy enabled HBc VLPs behave as a potent antitumor vaccine and this strategy to manipulate immunogenicity of VLPs may be suitable for other VLP-based vaccine vectors.


Assuntos
Vírus da Hepatite B , Vacinas de Partículas Semelhantes a Vírus , Animais , Camundongos , Vírus da Hepatite B/genética , Vacinas de Partículas Semelhantes a Vírus/genética , Antígenos de Neoplasias , Camundongos Endogâmicos BALB C
5.
Vaccine ; 40(42): 6141-6152, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36117002

RESUMO

Persistent infection of high-risk human papillomavirus (HPV) is a leading cause of some cancers, including cervical cancer. However, with over 20 carcinogenic HPV types, it is difficult to design a multivalent vaccine that can offer complete protection. Here, we describe the design and optimization of a HPV51/69/26 triple-type chimeric virus-like particle (VLP) for vaccine development. Using E. coli and a serial N-terminal truncation strategy, we created double- and triple-type chimeric VLPs through loop-swapping at equivalent surface loops. The lead candidate, H69-51BC-26FG, conferred similar particulate properties as that of its parental VLPs and comparable immunogenicity against HPV51, -69 and -26. When produced in a GMP-like facility, these H69-51BC-26FG VLPs were verified to have excellent qualities for the development of a multivalent HPV vaccine. This study showcases an amenable way to create a single VLP using type-specific epitope clustering for the design of a triple-type vaccine.


Assuntos
Alphapapillomavirus , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Vacinas de Partículas Semelhantes a Vírus , Animais , Anticorpos Antivirais , Proteínas do Capsídeo , Epitopos , Escherichia coli/genética , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Papillomaviridae/genética , Vacinas contra Papillomavirus/genética , Vacinas Combinadas , Vacinas de Partículas Semelhantes a Vírus/genética
6.
Vet Microbiol ; 272: 109512, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35853407

RESUMO

The objective of this study was to evaluate the efficacy of a recombinant porcine circovirus type 2 (PCV2) vaccine based from a Nicotiana benthamiana expression system against four different co-challenges with PCV2 genotypes (2a, 2b, 2d, and 2e) and porcine reproductive and respiratory syndrome virus (PRRSV). Pigs in the vaccinated groups each received a 1.0 mL intramuscularly of plant-based PCV2a vaccine in the neck muscle at 21 days of age. Vaccinates were then co-challenged with a combination of one of four PCV2 genotypes (2a, 2b, 2d, and 2e) and PRRSV at 42 days of age. Regardless of the PCV2 genotype used for challenge, vaccination significantly reduced clinical signs, reduced the level of PCV2 load in both blood and lymph nodes, and reduced the severity of lymphoid lesions in pigs. Vaccination resulted in significantly higher titers of neutralizing antibody against the corresponding PCV2 genotype evaluated and increased the frequency of PCV2-specific interferon-γ secreting cells. The results of this study demonstrated that a plant-based PCV2 vaccine conferred protection against a dual challenge with four different PCV2 genotypes when combined with PRRSV based on clinical, virological, immunological and pathological evaluation.


Assuntos
Infecções por Circoviridae , Circovirus , Vírus da Síndrome Respiratória e Reprodutiva Suína , Doenças dos Suínos , Vacinas de Partículas Semelhantes a Vírus , Vacinas Virais , Animais , Anticorpos Antivirais , Infecções por Circoviridae/prevenção & controle , Infecções por Circoviridae/veterinária , Circovirus/genética , Genótipo , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Suínos , Vacinas de Partículas Semelhantes a Vírus/genética
7.
Protein Expr Purif ; 197: 106106, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35525404

RESUMO

Rous sarcoma virus-like particles (RSV-LPs) displaying hemagglutinins of H1N1 (A/New Caledonia/20/99) (H1) and H5N1 (A/Vietnam/1194/2004) (H5) of the influenza A virus were produced. The H1 has its transmembrane domain, but the H5 was fused with the transmembrane domain of glycoprotein 64 (BmGP64) from Bombyx mori nucleopolyhedrovirus (BmNPV). H1 and RSV Gag protein were coexpressed in the hemolymph of silkworm larvae, copurified, and confirmed RSV-LP displaying H1 (VLP/H1). Similarly, the RSV-LP displaying H5 (VLP/H5) production was also achieved. Using fetuin agarose column chromatography, RSV Gag protein-coexpressed H1 and H5 in silkworms were copurified from the hemolymph. By immuno-TEM, H1 and H5 were observed on the surface of an RSV-LP, indicating the formation of bivalent RSV-LP displaying two HAs (VLP/BivHA) in the hemolymph of silkworm larvae. VLP/H1 induced the hemagglutination of red blood cells (RBCs) of chicken and rabbit but not sheep, while VLP/H5 induced the hemagglutination of RBCs of chicken and sheep but not rabbit. Additionally, VLP/BivHA allowed the hemagglutination of RBCs of all three animals. Silkworm larvae can produce RSV-LPs displaying two HAs and is a promising tool to produce the bivalent enveloped VLPs for the vaccine platform.


Assuntos
Bombyx , Vírus da Influenza A Subtipo H1N1 , Virus da Influenza A Subtipo H5N1 , Vacinas contra Influenza , Vacinas de Partículas Semelhantes a Vírus , Animais , Bombyx/genética , Bombyx/metabolismo , Produtos do Gene gag/metabolismo , Hemaglutininas/genética , Hemaglutininas/metabolismo , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/metabolismo , Larva/genética , Larva/metabolismo , Lipopolissacarídeos , Coelhos , Ovinos , Vacinas de Partículas Semelhantes a Vírus/genética
8.
Biotechnol Bioeng ; 119(5): 1207-1221, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35112714

RESUMO

Human immunodeficiency virus 1 (HIV-1) virus-like particles (VLPs) are nanostructures derived from the self-assembly and cell budding of Gag polyprotein. Mimicking the native structure of the virus and being noninfectious, they represent promising candidates for the development of new vaccines as they elicit a strong immune response. In addition to this, the bounding membrane can be functionalized with exogenous antigens to target different diseases. Protein glycosylation depends strictly on the production platform and expression system used and the displayed glycosylation patterns may influence downstream processing as well as the immune response. One of the main challenges for the development of Gag VLP production bioprocess is the separation of VLPs and coproduced extracellular vesicles (EVs). In this study, porous graphitized carbon separation method coupled with mass spectrometry was used to characterize the N- and O- glycosylation profiles of Gag VLPs produced in HEK293 cells. We identified differential glycan signatures between VLPs and EVs that could pave the way for further separation and purification strategies to optimize downstream processing and move forward in VLP-based vaccine production technology.


Assuntos
Vesículas Extracelulares , HIV-1 , Vacinas de Partículas Semelhantes a Vírus , Glicosilação , Células HEK293 , Humanos , Vacinas de Partículas Semelhantes a Vírus/genética
9.
Sci Rep ; 12(1): 1005, 2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-35046461

RESUMO

The pandemic of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has caused a public health emergency, and research on the development of various types of vaccines is rapidly progressing at an unprecedented development speed internationally. Some vaccines have already been approved for emergency use and are being supplied to people around the world, but there are still many ongoing efforts to create new vaccines. Virus-like particles (VLPs) enable the construction of promising platforms in the field of vaccine development. Here, we demonstrate that non-infectious SARS-CoV-2 VLPs can be successfully assembled by co-expressing three important viral proteins membrane (M), envelop (E) and nucleocapsid (N) in plants. Plant-derived VLPs were purified by sedimentation through a sucrose cushion. The shape and size of plant-derived VLPs are similar to native SARS-CoV-2 VLPs without spike. Although the assembled VLPs do not have S protein spikes, they could be developed as formulations that can improve the immunogenicity of vaccines including S antigens, and further could be used as platforms that can carry S antigens of concern for various mutations.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Proteínas M de Coronavírus/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , SARS-CoV-2/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Proteínas Viroporinas/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Vacinas contra COVID-19/administração & dosagem , Proteínas M de Coronavírus/genética , Proteínas M de Coronavírus/metabolismo , Proteínas do Nucleocapsídeo de Coronavírus/genética , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo , Humanos , Nicotiana/imunologia , Nicotiana/metabolismo , Nicotiana/virologia , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas de Partículas Semelhantes a Vírus/metabolismo , Proteínas Viroporinas/genética , Proteínas Viroporinas/metabolismo
10.
Arch Virol ; 166(10): 2733-2741, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34322722

RESUMO

Congenital tremor (CT) type A-II in piglets is a worldwide disease caused by an emerging atypical porcine pestivirus (APPV). Preparation and evaluation of vaccines in laboratory animals is an important preliminary step toward prevention and control of the disease. Here, virus-like particles (VLPs) of APPV were prepared and VLPs vaccine was evaluated in BALB/c mice. Purified Erns and E2 proteins expressed in E. coli were allowed to self-assemble into VLPs, which had the appearance of hollow spherical particles with a diameter of about 100 nm by transmission electron microscopy (TEM). The VLPs induced strong antibody responses and reduced the viral load in tissues of BALB/c mice. The data from animal challenge experiments, RT-PCR, and immunohistochemical analysis demonstrated that BALB/c mice are an appropriate laboratory model for APPV. These results suggest the feasibility of using VLPs as a vaccine for the prevention and control of APPV and provide useful information for further study of APPV in laboratory animals.


Assuntos
Infecções por Pestivirus/prevenção & controle , Pestivirus/imunologia , Vacinação/veterinária , Replicação Viral/efeitos dos fármacos , Animais , Anticorpos Antivirais/sangue , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Pestivirus/virologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Suínos , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/virologia , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas de Partículas Semelhantes a Vírus/imunologia , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/imunologia , Carga Viral , Vacinas Virais/genética , Vacinas Virais/imunologia
11.
Vaccine ; 39(35): 4979-4987, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34325930

RESUMO

BACKGROUND: Virus-like particles (VLPs) are unable to replicate in the recipient but stimulate the immune system through recognition of repetitive subunits. Parenterally delivered rotavirus-VLP (Ro-VLP) vaccine could have the potential to overcome the weaknesses of licensed oral live-attenuated rotavirus vaccines, namely, low efficacy in low-income and high mortality settings and a potential risk of intussusception. METHODS: A monovalent Ro-VLP composed of viral protein (VP) 7, VP6 and VP2 of G1 genotype specificity was produced in Nicotiana benthamiana using Agrobacterium tumefaciens infiltration-based transient recombinant expression system. Plants expressing recombinant G1 Ro-VLP were harvested, then the resultant biomass was processed through a series of clarification and purification steps including standard extraction, filtration, ultrafiltration and chromatography. The purified G1 Ro-VLP was subsequently examined for its immunogenicity and toxicological profile using animal models. RESULTS: G1 Ro-VLP had a purity of ≥90% and was structurally similar to triple-layered rotavirus particles as determined by cryogenic transmission electron microscopy. Two doses of aluminum hydroxide-adjuvanted G1 Ro-VLP (1 µg, 5 µg or 30 µg), administered intramuscularly, elicited a robust homotypic neutralizing antibody response in rats. Also, rabbits administered G1 Ro-VLP (10 µg or 30 µg) four times intramuscularly with aluminum hydroxide adjuvant did not show any significant toxicity. CONCLUSIONS: Plant-derived Ro-VLP composed of VP7, VP6 and VP2 structural proteins would be a plausible alternative to live-attenuated oral rotavirus vaccines currently distributed worldwide.


Assuntos
Infecções por Rotavirus , Vacinas contra Rotavirus , Rotavirus , Vacinas de Partículas Semelhantes a Vírus , Animais , Anticorpos Antivirais , Coelhos , Ratos , Rotavirus/genética , Infecções por Rotavirus/prevenção & controle , Vacinas Atenuadas , Vacinas de Partículas Semelhantes a Vírus/genética
12.
EMBO Rep ; 22(8): e52447, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34142428

RESUMO

Cyclic GMP-AMP (cGAMP) is an immunostimulatory molecule produced by cGAS that activates STING. cGAMP is an adjuvant when administered alongside antigens. cGAMP is also incorporated into enveloped virus particles during budding. Here, we investigate whether inclusion of cGAMP within viral vaccine vectors enhances their immunogenicity. We immunise mice with virus-like particles (VLPs) containing HIV-1 Gag and the vesicular stomatitis virus envelope glycoprotein G (VSV-G). cGAMP loading of VLPs augments CD4 and CD8 T-cell responses. It also increases VLP- and VSV-G-specific antibody titres in a STING-dependent manner and enhances virus neutralisation, accompanied by increased numbers of T follicular helper cells. Vaccination with cGAMP-loaded VLPs containing haemagglutinin induces high titres of influenza A virus neutralising antibodies and confers protection upon virus challenge. This requires cGAMP inclusion within VLPs and is achieved at markedly reduced cGAMP doses. Similarly, cGAMP loading of VLPs containing the SARS-CoV-2 Spike protein enhances Spike-specific antibody titres. cGAMP-loaded VLPs are thus an attractive platform for vaccination.


Assuntos
COVID-19 , Vacinas contra Influenza , Vacinas de Partículas Semelhantes a Vírus , Animais , Humanos , Camundongos , Nucleotídeos Cíclicos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Vacinas de Partículas Semelhantes a Vírus/genética
13.
Sci Rep ; 11(1): 6492, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33753816

RESUMO

Zika virus (ZIKV), a flavivirus transmitted primarily by infected mosquitos, can cause neurological symptoms such as Guillian-Barré syndrome and microcephaly. We developed several vaccinia virus (VACV) vaccine candidates for ZIKV based on replication-inducible VACVs (vINDs) expressing ZIKV pre-membrane (prM) and envelope (E) proteins (vIND-ZIKVs). These vIND-ZIKVs contain elements of the tetracycline operon and replicate only in the presence of tetracyclines. The pool of vaccine candidates was narrowed to one vIND-ZIKV containing a novel mutation in the signal peptide of prM that led to higher expression and secretion of E and production of virus-like particles, which was then tested for safety, immunogenicity, and efficacy in mice. vIND-ZIKV grows to high titers in vitro in the presence of doxycycline (DOX) but is replication-defective in vivo in the absence of DOX, causing no weight loss in mice. C57BL/6 mice vaccinated once with vIND-ZIKV in the absence of DOX (as a replication-defective virus) developed robust levels of E-peptide-specific IFN-γ-secreting splenocytes and anti-E IgG titers, with modest levels of serum-neutralizing antibodies. Vaccinated mice treated with anti-IFNAR1 antibody were completely protected from ZIKV viremia post-challenge after a single dose of vIND-ZIKV. Furthermore, mice with prior immunity to VACV developed moderate anti-E IgG titers that increased after booster vaccination, and were protected from viremia only after two vaccinations with vIND-ZIKV.


Assuntos
Imunogenicidade da Vacina , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vaccinia virus/genética , Infecção por Zika virus/prevenção & controle , Zika virus/imunologia , Animais , Chlorocebus aethiops , Feminino , Células HeLa , Humanos , Imunoglobulina G/imunologia , Interferon gama/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Baço/citologia , Baço/imunologia , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Vacinas de Partículas Semelhantes a Vírus/genética , Vaccinia virus/fisiologia , Células Vero , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/imunologia , Replicação Viral
14.
Protein Expr Purif ; 183: 105864, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33677084

RESUMO

In this study, we describe an optimized method of obtaining virus-like particles (VLPs) of the recombinant hepatitis C virus (HCV) core protein (HCcAg) expressed in yeast cells (Pichia pastoris), which can be used for the construction of diagnostic test systems and vaccine engineering. The described simplified procedure was developed to enable in vitro self-assembly of HCcAg molecules into VLPs during protein purification. In brief, the HCcAg protein was precipitated from yeast cell lysates with ammonium sulfate and renatured by gel filtration on Sephadex G-25 under reducing conditions. VLPs were self-assembled after the removal of the reducing agent by gel filtration on Sephadex G-25. Protein purity and specificity were evaluated by SDS-PAGE and immunoblotting analysis. The molecular mass of VLPs and their relative quantity were measured by HPLC, followed by confirmation of VLPs production and estimation of their shape and size by transmission electron microscopy. As a result, we obtained recombinant HCcAg preparation (with ~90% purity) in the form of VLPs and monomers, which has been used to produce hybridomas secreting monoclonal antibodies (mAbs) against HCcAg.


Assuntos
Anticorpos Monoclonais Murinos/imunologia , Hepacivirus , Anticorpos Anti-Hepatite C/imunologia , Saccharomycetales , Vacinas de Partículas Semelhantes a Vírus , Proteínas do Core Viral , Vacinas contra Hepatite Viral , Animais , Feminino , Hepacivirus/genética , Hepacivirus/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Saccharomycetales/genética , Saccharomycetales/metabolismo , Vacinas de Partículas Semelhantes a Vírus/biossíntese , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas de Partículas Semelhantes a Vírus/isolamento & purificação , Proteínas do Core Viral/biossíntese , Proteínas do Core Viral/genética , Proteínas do Core Viral/imunologia , Proteínas do Core Viral/isolamento & purificação , Vacinas contra Hepatite Viral/biossíntese , Vacinas contra Hepatite Viral/genética , Vacinas contra Hepatite Viral/imunologia , Vacinas contra Hepatite Viral/isolamento & purificação
15.
Plant Biotechnol J ; 19(4): 745-756, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33099859

RESUMO

Dengue virus (DENV) is an emerging threat causing an estimated 390 million infections per year. Dengvaxia, the only licensed vaccine, may not be adequately safe in young and seronegative patients; hence, development of a safer, more effective vaccine is of great public health interest. Virus-like particles (VLPs) are a safe and very efficient vaccine strategy, and DENV VLPs have been produced in various expression systems. Here, we describe the production of DENV VLPs in Nicotiana benthamiana using transient expression. The co-expression of DENV structural proteins (SP) and a truncated version of the non-structural proteins (NSPs), lacking NS5 that contains the RNA-dependent RNA polymerase, led to the assembly of DENV VLPs in plants. These VLPs were comparable in appearance and size to VLPs produced in mammalian cells. Contrary to data from other expression systems, expression of the protein complex prM-E was not successful, and strategies used in other expression systems to improve the VLP yield did not result in increased yields in plants but, rather, increased purification difficulties. Immunogenicity assays in BALB/c mice revealed that plant-made DENV1-SP + NSP VLPs led to a higher antibody response in mice compared with DENV-E domain III displayed inside bluetongue virus core-like particles and a DENV-E domain III subunit. These results are consistent with the idea that VLPs could be the optimal approach to creating candidate vaccines against enveloped viruses.


Assuntos
Vacinas contra Dengue , Imunidade Humoral , Vacinas de Partículas Semelhantes a Vírus , Proteínas Virais/imunologia , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Vírus da Dengue/genética , Camundongos , Camundongos Endogâmicos BALB C , Nicotiana , Vacinas de Partículas Semelhantes a Vírus/genética
16.
Front Immunol ; 11: 564627, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33133076

RESUMO

Despite extensive research, the development of an effective malaria vaccine remains elusive. The induction of robust and sustained T cell and antibody response by vaccination is an urgent unmet need. Chimeric virus-like particles (VLPs) are a promising vaccine platform. VLPs are composed of multiple subunit capsomeres which can be rapidly produced in a cost-effective manner, but the ability of capsomeres to induce antigen-specific cellular immune responses has not been thoroughly investigated. Accordingly, we have compared chimeric VLPs and their sub-unit capsomeres for capacity to induce CD8+ and CD4+ T cell and antibody responses. We produced chimeric murine polyomavirus VLPs and capsomeres each incorporating defined CD8+ T cell, CD4+ T cell or B cell repeat epitopes derived from Plasmodium yoelii CSP. VLPs and capsomeres were evaluated using both homologous or heterologous DNA prime/boost immunization regimens for T cell and antibody immunogenicity. Chimeric VLP and capsomere vaccine platforms induced robust CD8+ T cell responses at similar levels which was enhanced by a heterologous DNA prime. The capsomere platform was, however, more efficient at inducing CD4+ T cell responses and less efficient at inducing antigen-specific antibody responses. Our data suggest that capsomeres, which have significant manufacturing advantages over VLPs, should be considered for diseases where a T cell response is the desired outcome.


Assuntos
Anticorpos Antivirais/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito T/imunologia , Plasmodium yoelii/imunologia , Polyomavirus/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Animais , Proteínas do Capsídeo/imunologia , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/genética , Feminino , Imunidade Celular/imunologia , Imunização/métodos , Interferon gama/metabolismo , Vacinas Antimaláricas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Mutagênese Insercional , Vacinas de Partículas Semelhantes a Vírus/genética
17.
Vaccine ; 38(49): 7774-7779, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33164801

RESUMO

Virus-like particles (VLPs) are considered useful tools for vaccine development because they induce an immune response and are safe. In addition, VLPs may be useful as a platform for the presentation of foreign antigens to elicit immune responses. In this study, we aimed to produce a chimeric VLP composed of L1 protein of bovine papillomavirus type 6 (BPV6-L1) that can display an entire foreign protein on its surface. Based on prediction of the conformational structure of VLP of BPV6-L1 (BPV6-VLP), candidate insertion sites for the foreign protein into BPV6-VLP were identified. Fusion proteins of BPV6-L1 and EGFP as a model foreign protein were constructed and produced. Only the fusion protein in which EGFP was inserted between amino acids 136 and 137 of BPV6-L1 self-assembled into VLPs and did not exhibit hindrance of the conformation of EGFP. Chimeric BPV6-VLP-immunized mice produced specific IgG against both BPV6 and EGFP. This is the first demonstration of the production of an immunogenic, bivalent, chimeric BPV6-VLP incorporating an entire protein for stable surface display. Thus, immunogenic chimeric BPV6-VLP may constitute a promising vaccine platform.


Assuntos
Poxviridae , Vacinas de Partículas Semelhantes a Vírus , Animais , Camundongos , Papillomaviridae/genética , Vacinas de Partículas Semelhantes a Vírus/genética
18.
Front Immunol ; 11: 2074, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042118

RESUMO

Hepatitis B virus (HBV) is a global virus responsible for a universal disease burden for millions of people. Various vaccination strategies have been developed using viral vector, nucleic acid, protein, peptide, and virus-like particles (VLPs) to stimulate favorable immune responses against HBV. Given the pivotal role of specific immune responses of hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) in infection control, we designed a VLP-based vaccine by placing the antibody-binding fragments of HBsAg in the major immunodominant region (MIR) epitope of HBcAg to stimulate multilateral immunity. A computational approach was employed to predict and evaluate the conservation, antigenicity, allergenicity, and immunogenicity of the construct. Modeling and molecular dynamics (MD) demonstrated the folding stability of HBcAg as a carrier in inserting Myrcludex and "a" determinant of HBsAg. Regions 1-50 and 118-150 of HBsAg were considered to have the highest stability to be involved in the designed vaccine. Molecular docking revealed appropriate interactions between the B cell epitope of the designed vaccine and the antibodies. Totally, the final construct was promising for inducing humoral and cellular responses against HBV.


Assuntos
Linfócitos B/imunologia , Biologia Computacional/métodos , Vacinas contra Hepatite B/imunologia , Vírus da Hepatite B/fisiologia , Hepatite B/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Proteínas do Envelope Viral/imunologia , Simulação por Computador , Vacinas contra Hepatite B/genética , Humanos , Epitopos Imunodominantes/genética , Fragmentos Fab das Imunoglobulinas/genética , Simulação de Dinâmica Molecular , Vacinas de Partículas Semelhantes a Vírus/genética , Proteínas do Envelope Viral/genética
19.
J Proteome Res ; 19(11): 4516-4532, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-32975947

RESUMO

Vaccine therapies based on virus-like particles (VLPs) are currently in the spotlight due to their potential for generating high immunogenic responses while presenting fewer side effects than conventional vaccines. These self-assembled nanostructures resemble the native conformation of the virus but lack genetic material. They are becoming a promising platform for vaccine candidates against several diseases due to the ability of modifying their membrane with antigens from different viruses. The coproduction of extracellular vesicles (EVs) when producing VLPs is a key phenomenon currently still under study. In order to characterize this extracellular environment, a quantitative proteomics approach has been carried out. Three conditions were studied: non-transfected, transfected with an empty plasmid as control, and transfected with a plasmid coding for HIV-1 Gag polyprotein. A shift in EV biogenesis has been detected upon transfection, changing the production from large to small EVs. Another remarkable trait found was the presence of DNA being secreted within vesicles smaller than 200 nm. Studying the protein profile of these biological nanocarriers, it was observed that EVs were reflecting an overall energy homeostasis disruption via mitochondrial protein deregulation. Also, immunomodulatory proteins like ITGB1, ENO3, and PRDX5 were identified and quantified in VLP and EV fractions. These findings provide insight on the nature of the VLP extracellular environment defining the characteristics and protein profile of EVs, with potential to develop new downstream separation strategies or using them as adjuvants in viral therapies.


Assuntos
Vesículas Extracelulares , Vacinas de Partículas Semelhantes a Vírus , Células HEK293 , Humanos , Transfecção , Vacinas de Partículas Semelhantes a Vírus/genética
20.
Cell Res ; 30(10): 936-939, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32801356
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