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2.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360889

RESUMO

Despite extensive research, there is still no vaccine against the hepatitis C virus (HCV). The aim of this study was to investigate whether MSCs can exhibit adjuvant properties during DNA vaccination against hepatitis C. We used the pcNS3-NS5B plasmid encoding five nonstructural HCV proteins and MSCs derived from mice bone marrow. Five groups of DBA mice were immunized with the plasmid and/or MSCs in a different order. Group 1 was injected with the plasmid twice at intervals of 3 weeks; Group 2 with the plasmid, and after 24 h with MSCs; Group 3 with MSCs followed by the plasmid the next day; Group 4 with only MSCs; and Group 5 with saline. When the MSCs were injected prior to DNA immunization, the cell immune response to HCV proteins assessed by the level of IFN-γ synthesis was markedly increased compared to DNA alone. In contrast, MSCs injected after DNA suppressed the immune response. Apparently, the high level of proinflammatory cytokines detected after DNA injection promotes the conversion of MSCs introduced later into the immunosuppressive MSC2. The low level of cytokines in mice before MSC administration promotes the high immunostimulatory activity of MSC1 in response to a DNA vaccine. Thus, when administered before DNA, MSCs are capable of exhibiting promising adjuvant properties.


Assuntos
Genes Virais/imunologia , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/prevenção & controle , Imunidade Celular , Células-Tronco Mesenquimais/imunologia , Vacinação/métodos , Vacinas de DNA/administração & dosagem , Proteínas não Estruturais Virais/genética , Animais , Linhagem Celular Tumoral , Citocinas/metabolismo , Feminino , Hepatite C/imunologia , Hepatite C/virologia , Humanos , Camundongos , Camundongos Endogâmicos DBA , Plasmídeos/genética , Linfócitos T/imunologia , Transfecção , Resultado do Tratamento , Vacinas de DNA/imunologia
3.
Front Immunol ; 12: 612910, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248928

RESUMO

Hepatocyte infection by malaria sporozoites is a bottleneck in the life-cycle of Plasmodium spp. including P. falciparum, which causes the most lethal form of malaria. Therefore, developing an effective vaccine capable of inducing the strong humoral and cellular immune responses necessary to block the pre-erythrocytic stage has potential to overcome the spatiotemporal hindrances pertaining to parasite biology and hepatic microanatomy. We recently showed that when combined with a human adenovirus type 5 (AdHu5)-priming vaccine, adeno-associated virus serotype 1 (AAV1) is a potent booster malaria vaccine vector capable of inducing strong and long-lasting protective immune responses in a rodent malaria model. Here, we evaluated the protective efficacy of a hepatotropic virus, adeno-associated virus serotype 8 (AAV8), as a booster vector because it can deliver a transgene potently and rapidly to the liver, the organ malaria sporozoites initially infect and multiply in following sporozoite injection by the bite of an infected mosquito. We first generated an AAV8-vectored vaccine expressing P. falciparum circumsporozoite protein (PfCSP). Intravenous (i.v.) administration of AAV8-PfCSP to mice initially primed with AdHu5-PfCSP resulted in a hepatocyte transduction rate ~2.5 times above that seen with intramuscular (i.m.) administration. This immunization regimen provided a better protection rate (100% sterile protection) than that of the i.m. AdHu5-prime/i.m. AAV8-boost regimen (60%, p < 0.05), i.m. AdHu5-prime/i.v. AAV1-boost (78%), or i.m. AdHu5-prime/i.m. AAV1-boost (80%) against challenge with transgenic PfCSP-expressing P. berghei sporozoites. Compared with the i.m. AdHu5-prime/i.v. AAV1-boost regimen, three other regimens induced higher levels of PfCSP-specific humoral immune responses. Importantly, a single i.v. dose of AAV8-PfCSP recruited CD8+ T cells, especially resident memory CD8+ T cells, in the liver. These data suggest that boost with i.v. AAV8-PfCSP can improve humoral and cellular immune responses in BALB/c mice. Therefore, this regimen holds great promise as a next-generation platform for the development of an effective malaria vaccine.


Assuntos
Dependovirus/imunologia , Imunização Secundária/métodos , Fígado/imunologia , Vacinas Antimaláricas/imunologia , Malária Falciparum/prevenção & controle , Plasmodium falciparum/imunologia , Vacinas contra Adenovirus/imunologia , Animais , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular , Dependovirus/genética , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Memória Imunológica , Fígado/citologia , Fígado/efeitos dos fármacos , Vacinas Antimaláricas/administração & dosagem , Malária Falciparum/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas de Protozoários/imunologia , Vacinas de DNA/imunologia
4.
Front Immunol ; 12: 658519, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34276652

RESUMO

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a highly pathogenic novel virus that has caused a massive pandemic called coronavirus disease 2019 (COVID-19) worldwide. Wuhan, a city in China became the epicenter of the outbreak of COVID-19 in December 2019. The disease was declared a pandemic globally by the World Health Organization (WHO) on 11 March 2020. SARS-CoV-2 is a beta CoV of the Coronaviridae family which usually causes respiratory symptoms that resemble common cold. Multiple countries have experienced multiple waves of the disease and scientific experts are consistently working to find answers to several unresolved questions, with the aim to find the most suitable ways to contain the virus. Furthermore, potential therapeutic strategies and vaccine development for COVID-19 management are also considered. Currently, substantial efforts have been made to develop successful and safe treatments and SARS-CoV-2 vaccines. Some vaccines, such as inactivated vaccines, nucleic acid-based, and vector-based vaccines, have entered phase 3 clinical trials. Additionally, diverse small molecule drugs, peptides and antibodies are being developed to treat COVID-19. We present here an overview of the virus interaction with the host and environment and anti-CoV therapeutic strategies; including vaccines and other methodologies, designed for prophylaxis and treatment of SARS-CoV-2 infection with the hope that this integrative analysis could help develop novel therapeutic approaches against COVID-19.


Assuntos
Vacinas contra COVID-19/uso terapêutico , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pandemias/prevenção & controle , SARS-CoV-2/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/uso terapêutico , Antivirais/uso terapêutico , COVID-19/tratamento farmacológico , COVID-19/imunologia , Vacinas contra COVID-19/imunologia , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Imunidade , Taxa de Mutação , SARS-CoV-2/genética , Bibliotecas de Moléculas Pequenas/uso terapêutico , Vacinas de DNA/imunologia , Vacinas de DNA/uso terapêutico , Vacinas de Produtos Inativados/imunologia , Vacinas de Produtos Inativados/uso terapêutico
5.
Cancer Sci ; 112(9): 3469-3483, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34157192

RESUMO

Renal carcinoma shows a high risk of invasion and metastasis without effective treatment. Herein, we developed a chitosan (CS) nanoparticle-mediated DNA vaccine containing an activated factor L-Myc and a tumor-specific antigen CAIX for renal carcinoma treatment. The subcutaneous tumor models were intramuscularly immunized with CS-pL-Myc/pCAIX or control vaccine, respectively. Compared with single immunization group, the tumor growth was significantly suppressed in CS-pL-Myc/pCAIX co-immunization group. The increased proportion and mature of CD11c+ DCs, CD8+ CD11c+ DCs and CD103+ CD11c+ DCs were observed in the splenocytes from CS-pL-Myc/pCAIX co-immunized mice. Furthermore, the enhanced antigen-specific CD8+ T lymphocyte proliferation, cytotoxic T lymphocyte (CTL) responses, and multi-functional CD8+ T cell induction were detected in CS-pL-Myc/pCAIX co-immunization group compared with CS-pCAIX immunization group. Of note, the depletion of CD8 T cells resulted in the reduction of CD8+ T cells or CD8+ CD11c+ DCs and the loss of anti-tumor efficacy induced by CS-pL-Myc/pCAIX vaccine, suggesting the therapeutic efficacy of the vaccine was required for CD8+ DCs and CD103+ DCs mediated CD8+ T cells responses. Likewise, CS-pL-Myc/pCAIX co-immunization also significantly inhibited the lung metastasis of renal carcinoma models accompanied with the increased induction of multi-functional CD8+ T cell responses. Therefore, these results indicated that CS-pL-Myc/pCAIX vaccine could effectively induce CD8+ DCs and CD103+ DCs mediated tumor-specific multi-functional CD8+ T cell responses and exert the anti-tumor efficacy. This vaccine strategy offers a potential and promising approach for solid or metastatic tumor treatment.


Assuntos
Antígenos CD/metabolismo , Antígenos de Neoplasias/administração & dosagem , Antígenos CD8/metabolismo , Linfócitos T CD8-Positivos/imunologia , Anidrase Carbônica IX/administração & dosagem , Carcinoma de Células Renais/terapia , Quitosana/química , Células Dendríticas/imunologia , Sistemas de Liberação de Medicamentos/métodos , Imunidade , Imunização/métodos , Cadeias alfa de Integrinas/metabolismo , Neoplasias Renais/terapia , Nanopartículas/química , Proteínas Proto-Oncogênicas c-myc/administração & dosagem , Vacinas de DNA/administração & dosagem , Animais , Antígenos de Neoplasias/genética , Anidrase Carbônica IX/genética , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/patologia , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Proto-Oncogênicas c-myc/genética , Resultado do Tratamento , Vacinas de DNA/imunologia
6.
Emerg Microbes Infect ; 10(1): 1390-1403, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34120577

RESUMO

Global concerns arose as the emerged and rapidly spreading SARS-CoV-2 variants might escape host immunity induced by vaccination. In this study, a heterologous prime-boost immunization strategy for COVID-19 was designed to prime with a DNA vaccine encoding wild type (WT) spike protein receptor-binding domain (RBD) followed by S1 protein-based vaccine in rabbits. Four vaccine-elicited rabbit monoclonal antibodies (RmAbs), including 1H1, 9H1, 7G5, and 5E1, were isolated for biophysical property, neutralization potency and sequence analysis. All RmAbs recognized RBD or S1 protein with KD in the low nM or sub nM range. 1H1 and 9H1, but neither 7G5 nor 5E1, can bind to all RBD protein variants derived from B.1.351. All four RmAbs were able to neutralize wild type (WT) SARS-CoV-2 strain in pseudovirus assay, and 1H1 and 9H1 could neutralize the SARS-CoV-2 WT authentic virus with IC50 values of 0.136 and 0.026 µg/mL, respectively. Notably, 1H1 was able to neutralize all 6 emerging SARS-CoV-2 variants tested including D614G, B.1.1.7, B.1.429, P.1, B.1.526, and B.1.351 variants, and 5E1 could neutralize against the above 5 variants except P.1. Epitope binning analysis revealed that 9H1, 5E1 and 1H1 recognized distinct epitopes, while 9H1 and 7G5 may have overlapping but not identical epitope. In conclusion, DNA priming protein boost vaccination was an effective strategy to induce RmAbs with potent neutralization capability against not only SARS-CoV-2 WT strain but also emergent variants, which may provide a new avenue for effective therapeutics and point-of-care diagnostic measures.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Variação Genética , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Vacinas de DNA/imunologia , Animais , Anticorpos Antivirais/sangue , Epitopos , Humanos , Imunização Secundária , Domínios Proteicos/imunologia , Domínios Proteicos/fisiologia , Coelhos , SARS-CoV-2/imunologia , Vacinação , Vacinas Sintéticas , Ligação Viral
7.
Int Immunopharmacol ; 96: 107763, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34162141

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the rapidly spreading pandemic COVID-19 in the world. As an effective therapeutic strategy is not introduced yet and the rapid genetic variations in the virus, there is an emerging necessity to design, evaluate and apply effective new vaccines. An acceptable vaccine must elicit both humoral and cellular immune responses, must have the least side effects and the storage and transport systems should be available and affordable for all countries. These vaccines can be classified into different types: inactivated vaccines, live-attenuated virus vaccines, subunit vaccines, virus-like particles (VLPs), nucleic acid-based vaccines (DNA and RNA) and recombinant vector-based vaccines (replicating and non-replicating viral vector). According to the latest update of the WHO report on April 2nd, 2021, at least 85 vaccine candidates were being studied in clinical trial phases and 184 candidate vaccines were being evaluated in pre-clinical stages. In addition, studies have shown that other vaccines, including the Bacillus Calmette-Guérin (BCG) vaccine and the Plant-derived vaccine, may play a role in controlling pandemic COVID-19. Herein, we reviewed the different types of COVID-19 candidate vaccines that are currently being evaluated in preclinical and clinical trial phases along with advantages, disadvantages or adverse reactions, if any.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Vacina BCG/imunologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/efeitos adversos , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Masculino , Metanálise como Assunto , Pessoa de Meia-Idade , Vacinas de DNA/imunologia , Vacinas de Produtos Inativados/imunologia , Vacinas de Subunidades/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas Virais/imunologia
8.
PLoS Negl Trop Dis ; 15(5): e0009374, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34043618

RESUMO

The development of efficient vaccines against COVID-19 is an emergent need for global public health. The spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a major target for the COVID-19 vaccine. To quickly respond to the outbreak of the SARS-CoV-2 pandemic, a nucleic acid-based vaccine is a novel option, beyond the traditional inactivated virus vaccine or recombinant protein vaccine. Here, we report a DNA vaccine containing the spike gene for delivery via electroporation. The spike genes of SARS-CoV and SARS-CoV-2 were codon optimized for mammalian cell expression and then cloned into mammalian cell expression vectors, called pSARS-S and pSARS2-S, respectively. Spike protein expression was confirmed by immunoblotting after transient expression in HEK293T cells. After immunization, sera were collected for antigen-specific antibody and neutralizing antibody titer analyses. We found that both pSARS-S and pSARS2-S immunization induced similar levels of antibodies against S2 of SARS-CoV-2. In contrast, only pSARS2-S immunization induced antibodies against the receptor-binding domain of SARS-CoV-2. We further found that pSARS2-S immunization, but not pSARS-S immunization, could induce very high titers of neutralizing antibodies against SARS-CoV-2. We further analyzed SARS-CoV-2 S protein-specific T cell responses and found that the immune responses were biased toward Th1. Importantly, pSARS2-S immunization in hamsters could induce protective immunity against SARS-CoV-2 challenge in vivo. These data suggest that DNA vaccination could be a promising approach for protecting against COVID-19.


Assuntos
COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas de DNA/normas , Animais , Chlorocebus aethiops , Cricetinae , Eletroporação , Células HEK293 , Humanos , Mesocricetus , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Plasmídeos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Vacinas de DNA/imunologia , Células Vero
9.
Front Immunol ; 12: 627688, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33790899

RESUMO

Heterologous prime-boost immunization regimens are a common strategy for many vaccines. DNA prime rAd5-GP boost immunization has been demonstrated to protect non-human primates against a lethal challenge of Ebola virus, a pathogen that causes fatal hemorrhagic disease in humans. This protection correlates with antibody responses and is also associated with IFNγ+ TNFα+ double positive CD8+ T-cells. In this study, we compared single DNA vs. multiple DNA prime immunizations, and short vs. long time intervals between the DNA prime and the rAd5 boost to evaluate the impact of these different prime-boost strategies on vaccine-induced humoral and cellular responses in non-human primates. We demonstrated that DNA/rAd5 prime-boost strategies can be tailored to induce either CD4+ T-cell or CD8+ T-cell dominant responses while maintaining a high magnitude antibody response. Additionally, a single DNA prime immunization generated a stable memory response that could be boosted by rAd5 3 years later. These results suggest DNA/rAd5 prime-boost provides a flexible platform that can be fine-tuned to generate desirable T-cell memory responses.


Assuntos
Vacinas contra Ebola/administração & dosagem , Ebolavirus/imunologia , Doença pelo Vírus Ebola/prevenção & controle , Esquemas de Imunização , Imunização Secundária , Imunogenicidade da Vacina , Animais , Anticorpos Antivirais/sangue , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , Vacinas contra Ebola/imunologia , Ebolavirus/patogenicidade , Feminino , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/virologia , Memória Imunológica , Macaca fascicularis , Fatores de Tempo , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia
10.
Front Immunol ; 12: 623996, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33717130

RESUMO

The search for a preventive vaccine against HIV infection remains an ongoing challenge, indicating the need for novel approaches. Parainfluenza virus 5 (PIV5) is a paramyxovirus replicating in the upper airways that is not associated with any animal or human pathology. In animal models, PIV5-vectored vaccines have shown protection against influenza, RSV, and other human pathogens. Here, we generated PIV5 vaccines expressing HIV envelope (Env) and SIV Gag and administered them intranasally to macaques, followed by boosting with virus-like particles (VLPs) containing trimeric HIV Env. Moreover, we compared the immune responses generated by PIV5-SHIV prime/VLPs boost regimen in naïve vs a control group in which pre-existing immunity to the PIV5 vector was established. We demonstrate for the first time that intranasal administration of PIV5-based HIV vaccines is safe, well-tolerated and immunogenic, and that boosting with adjuvanted trimeric Env VLPs enhances humoral and cellular immune responses. The PIV5 prime/VLPs boost regimen induced robust and durable systemic and mucosal Env-specific antibody titers with functional activities including ADCC and neutralization. This regimen also induced highly polyfunctional antigen-specific T cell responses. Importantly, we show that diminished responses due to PIV5 pre-existing immunity can be overcome in part with VLP protein boosts. Overall, these results establish that PIV5-based HIV vaccine candidates are promising and warrant further investigation including moving on to primate challenge studies.


Assuntos
Vacinas contra a AIDS/administração & dosagem , Produtos do Gene gag/administração & dosagem , HIV-1/imunologia , Imunogenicidade da Vacina , Vírus da Parainfluenza 5/imunologia , Vírus da Imunodeficiência Símia/imunologia , Vírion/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/administração & dosagem , Vacinas contra a AIDS/genética , Vacinas contra a AIDS/imunologia , Administração Intranasal , Animais , Anticorpos Antivirais/sangue , Bovinos , Linhagem Celular , Produtos do Gene gag/genética , Produtos do Gene gag/imunologia , HIV-1/genética , Interações Hospedeiro-Patógeno , Imunidade Celular , Imunidade Humoral , Imunidade nas Mucosas , Macaca mulatta , Masculino , Mucosa Nasal/imunologia , Mucosa Nasal/virologia , Vírus da Parainfluenza 5/genética , Vírus da Imunodeficiência Símia/genética , Linfócitos T/imunologia , Linfócitos T/virologia , Vacinação , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia , Vírion/genética , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia
11.
Mol Immunol ; 134: 141-149, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33773157

RESUMO

The efficacy of DNA vaccine is associated closely with the expression of the antigen and the intensity of local immune responses. In our previous study, a recombinant DNA plasmid expressing the VAA protein (pVAA) of Listonella anguillarum has been proved to have a good protection against the infection of L. anguillarum. In the present study, the local immune responses eliciting by immunizing flounder with intramuscular (I.M.) injection of pVAA was investigated at the cellular and genetic level, the muscle at the injection site at 7th post vaccination day was sampled and analyzed by hematoxylin-eosin (H&E) staining, immunohistochemistry (IHC), flow cytometry (FCM), RNA sequencing (RNA-Seq)-based transcriptomics and RT-qPCR. Then variations on the specific antibodies in serum at 1st-6th post vaccination week and the relative percent survival rate (RPS) at following 14 days after challenge were measured. The H&E results showed that inflammatory cells and immune cells significantly increased at the injection site. The IHC using monoclonal antibody against T cell markers revealed that both CD4-1+ and CD4-2+ T lymphocytes were recruited to the injection site and FCM results showed that the proportion of CD4-1+ cells in pVAA immunized group was 28.6 %, in the control group was 8.7 %, and that of CD4-2+ cells in two groups was 21.2 % and 8.5 %, respectively. These results indicating that the proportion of CD4+ cells in the immune group was significantly increased compared with the control group. Moreover, there were 2551 genes differently expressed in pVAA immunized group, KEGG analysis showed the genes involved in the signal transduction and immune system, and surface markers for B-cells genes, T-cells and antigen presenting cells (APCs) genes were highly upregulated, suggesting the activation of the systemic immune responses. Antibody specific anti-L. anguillarum or anti-rVAA antibodies were significantly induced at 2nd post-immunization week, that reached a peak at 4-5th week. RPS in pVAA group was 53.85±3.64 %. In conclusion, pVAA induced effective local immune responses and then the systematic response. This probably is the main contribution of pVAA to effective protection against L. anguillarum.


Assuntos
Vacinas Bacterianas/imunologia , Doenças dos Peixes/prevenção & controle , Linguado/parasitologia , Vacinas de DNA/imunologia , Vibrioses/veterinária , Adesinas Bacterianas/imunologia , Animais , Doenças dos Peixes/imunologia , Vibrio
12.
Viruses ; 13(3)2021 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673603

RESUMO

The emergence of multiple concurrent infectious diseases localized in the world creates a complex burden on global public health systems. Outbreaks of Ebola, Lassa, and Marburg viruses in overlapping regions of central and West Africa and the co-circulation of Zika, Dengue, and Chikungunya viruses in areas with A. aegypti mosquitos highlight the need for a rapidly deployable, safe, and versatile vaccine platform readily available to respond. The DNA vaccine platform stands out as such an application. Here, we present proof-of-concept studies from mice, guinea pigs, and nonhuman primates for two multivalent DNA vaccines delivered using in vivo electroporation (EP) targeting mosquito-borne (MMBV) and hemorrhagic fever (MHFV) viruses. Immunization with MMBV or MHFV vaccines via intradermal EP delivery generated robust cellular and humoral immune responses against all target viral antigens in all species. MMBV vaccine generated antigen-specific binding antibodies and IFNγ-secreting lymphocytes detected in NHPs up to six months post final immunization, suggesting induction of long-term immune memory. Serum from MHFV vaccinated NHPs demonstrated neutralizing activity in Ebola, Lassa, and Marburg pseudovirus assays indicating the potential to offer protection. Together, these data strongly support and demonstrate the versatility of DNA vaccines as a multivalent vaccine development platform for emerging infectious diseases.


Assuntos
Culicidae/virologia , Ebolavirus/imunologia , Vacinas Combinadas/imunologia , Vacinas de DNA/imunologia , África Ocidental , Animais , Anticorpos Antivirais/imunologia , Arenavirus do Novo Mundo/imunologia , Vírus da Dengue/imunologia , Epidemias , Feminino , Cobaias , Doença pelo Vírus Ebola/imunologia , Imunidade Humoral/imunologia , Imunização/métodos , Febre Lassa/imunologia , Marburgvirus/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Vacinação/métodos , Vacinas Virais/imunologia , Zika virus/imunologia , Infecção por Zika virus/imunologia
13.
Commun Biol ; 4(1): 329, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712740

RESUMO

Maternal antibodies (MAbs) protect against infections in immunologically-immature neonates. Maternally transferred immunity may also be harnessed to target diseases associated with endogenous protein misfolding and aggregation, such as Alzheimer's disease (AD) and AD-pathology in Down syndrome (DS). While familial early-onset AD (fEOAD) is associated with autosomal dominant mutations in the APP, PSEN1,2 genes, promoting cerebral Amyloid-ß (Aß) deposition, DS features a life-long overexpression of the APP and DYRK1A genes, leading to a cognitive decline mediated by Aß overproduction and tau hyperphosphorylation. Although no prenatal screening for fEOAD-related mutations is in clinical practice, DS can be diagnosed in utero. We hypothesized that anti-Aß MAbs might promote the removal of early Aß accumulation in the central nervous system of human APP-expressing mice. To this end, a DNA-vaccine expressing Aß1-11 was delivered to wild-type female mice, followed by mating with 5xFAD males, which exhibit early Aß plaque formation. MAbs reduce the offspring's cortical Aß levels 4 months after antibodies were undetectable, along with alleviating short-term memory deficits. MAbs elicit a long-term shift in microglial phenotype in a mechanism involving activation of the FcγR1/Syk/Cofilin pathway. These data suggest that maternal immunization can alleviate cognitive decline mediated by early Aß deposition, as occurs in EOAD and DS.


Assuntos
Doença de Alzheimer/enzimologia , Doença de Alzheimer/prevenção & controle , Vacinas contra Alzheimer/administração & dosagem , Peptídeos beta-Amiloides/metabolismo , Anticorpos/metabolismo , Encéfalo/enzimologia , Fragmentos de Peptídeos/administração & dosagem , Fagocitose , Receptores de IgG/metabolismo , Quinase Syk/metabolismo , Doença de Alzheimer/imunologia , Doença de Alzheimer/patologia , Vacinas contra Alzheimer/imunologia , Peptídeos beta-Amiloides/administração & dosagem , Peptídeos beta-Amiloides/imunologia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Anticorpos/imunologia , Comportamento Animal , Encéfalo/imunologia , Encéfalo/patologia , Cognição , Modelos Animais de Doenças , Feminino , Imunização , Masculino , Memória , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/enzimologia , Microglia/imunologia , Microglia/patologia , Fragmentos de Peptídeos/imunologia , Fenótipo , Placa Amiloide , Transdução de Sinais , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia
14.
Parasitol Res ; 120(5): 1861-1871, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33689009

RESUMO

Coccidiosis triggered by Eimeria tenella is accompanied by haemorrhagic caecum and high morbidity. Vaccines are preferable choices to replace chemical drugs against coccidiosis. Surface antigens of apicomplexan parasites can adhere to host cells during the infection process. Therefore, truncated fragments coding E. tenella surface antigen 16 (EtSAG16) and 22 (EtSAG22) were cloned into pET-28a prokaryotic vector to express recombinant protein 16 (rEtSAG16) and 22 (rEtSAG22), respectively. Likewise, pEGFP-N1-EtSAG16 and pEGFP-N1-EtSAG22 plasmids were constructed using pEGFP-N1 eukaryotic vector. Further, pEGFP-N1-EtSAG4-16-22 multiple gene plasmid carrying EtSAG4, 16 and 22 were designed as cocktail vaccines to study integral immunoprotective effects. Western blot and RT-PCR (reverse transcription) assay were performed to verify expressions of EtSAG16 and 22 genes. Immunoprotective effects of recombinant protein or DNA vaccine were evaluated using different doses (50 or 100 µg) in vivo. All chickens in the vaccination group showed higher cytokine concentration (IFN-γ and IL-17), raised IgY antibody level, increased weight gain, lower caecum lesion score and reduced oocyst shedding compared with infection control groups (p < 0.05). The highest anticoccidial index (ACI) value 173.11 was from the pEGFP-N1-EtSAG4-16-22 plasmid (50 µg) group. In conclusion, EtSAG16 and 22 might be alternative candidate genes for generating vaccines against E. tenella infection.


Assuntos
Coccidiose/veterinária , Eimeria tenella/imunologia , Doenças das Aves Domésticas/prevenção & controle , Proteínas de Protozoários/imunologia , Vacinas Protozoárias/imunologia , Vacinas de DNA/imunologia , Animais , Antígenos de Superfície/imunologia , Galinhas/parasitologia , Coccidiose/imunologia , Coccidiose/prevenção & controle , Citocinas/imunologia , Eimeria tenella/genética , Imunogenicidade da Vacina , Oocistos/imunologia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/parasitologia , Proteínas de Protozoários/genética , Proteínas Recombinantes/imunologia , Vacinas Sintéticas/imunologia
15.
Front Immunol ; 12: 615011, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33717102

RESUMO

Introduction: Borrelia burgdorferi sensu lato (sl) is the causative agent of Lyme borreliosis. Currently there is no human vaccine against Lyme borreliosis, and most research focuses on recombinant protein vaccines. DNA tattoo vaccination with B. afzelii strain PKo OspC in mice has proven to be fully protective against B. afzelii syringe challenge and induces a favorable humoral immunity compared to recombinant protein vaccination. Alternatively, several recombinant protein vaccines based on tick proteins have shown promising effect in tick-bite infection models. In this study, we evaluated the efficacy of DNA vaccines against Borrelia OspC or tick antigens in a tick-bite infection model. Method: We vaccinated C3H/HeN mice with OspC using a codon-optimized DNA vaccine or with recombinant protein. We challenged these mice with B. burgdorferi sensu stricto (ss)-infected Ixodes scapularis nymphs. Subsequently, we vaccinated C3H/HeN mice with DNA vaccines coding for tick proteins for which recombinant protein vaccines have previously resulted in interference with tick feeding and/or Borrelia transmission: Salp15, tHRF, TSLPI, and Tix-5. These mice were also challenged with B. burgdorferi ss infected Ixodes scapularis nymphs. Results: DNA tattoo and recombinant OspC vaccination both induced total IgG responses. Borrelia cultures and DNA loads of skin and bladder remained negative in the mice vaccinated with OspC DNA vaccination, except for one culture. DNA vaccines against tick antigens Salp15 and Tix-5 induced IgG responses, while those against tHRF and TSLPI barely induced any IgG response. In addition, Borrelia cultures, and DNA loads from mice tattooed with DNA vaccines against tick proteins TSLPI, Salp15, tHRF, and Tix-5 were all positive. Conclusion: A DNA tattoo vaccine against OspC induced high specific IgG titers and provided near total protection against B. burgdorferi ss infection by tick challenge. In contrast, DNA tattoo vaccines against tick proteins TSLPI, Salp15, tHRF, and Tix-5 induced low to moderate IgG titers and did not provide protection. Therefore, DNA tattoo vaccination does not seem a suitable vaccine strategy to identify, or screen for, tick antigens for anti-tick vaccines. However, DNA tattoo vaccination is a straightforward and effective vaccination platform to assess novel B. burgdorferi sl antigen candidates in a relevant tick challenge model.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Artrópodes/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Borrelia burgdorferi/imunologia , Ixodes/imunologia , Vacinas contra Doença de Lyme/imunologia , Doença de Lyme/prevenção & controle , Vacinas de DNA/imunologia , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Borrelia burgdorferi/genética , Feminino , Imunização , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Doença de Lyme/transmissão , Camundongos
16.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33688035

RESUMO

Modified vaccinia virus Ankara (MVA) is a replication-restricted smallpox vaccine, and numerous clinical studies of recombinant MVAs (rMVAs) as vectors for prevention of other infectious diseases, including COVID-19, are in progress. Here, we characterize rMVAs expressing the S protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Modifications of full-length S individually or in combination included two proline substitutions, mutations of the furin recognition site, and deletion of the endoplasmic retrieval signal. Another rMVA in which the receptor binding domain (RBD) is flanked by the signal peptide and transmembrane domains of S was also constructed. Each modified S protein was displayed on the surface of rMVA-infected cells and was recognized by anti-RBD antibody and soluble hACE2 receptor. Intramuscular injection of mice with the rMVAs induced antibodies, which neutralized a pseudovirus in vitro and, upon passive transfer, protected hACE2 transgenic mice from lethal infection with SARS-CoV-2, as well as S-specific CD3+CD8+IFNγ+ T cells. Antibody boosting occurred following a second rMVA or adjuvanted purified RBD protein. Immunity conferred by a single vaccination of hACE2 mice prevented morbidity and weight loss upon intranasal infection with SARS-CoV-2 3 wk or 7 wk later. One or two rMVA vaccinations also prevented detection of infectious SARS-CoV-2 and subgenomic viral mRNAs in the lungs and greatly reduced induction of cytokine and chemokine mRNAs. A low amount of virus was found in the nasal turbinates of only one of eight rMVA-vaccinated mice on day 2 and none later. Detection of low levels of subgenomic mRNAs in turbinates indicated that replication was aborted in immunized animals.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Vetores Genéticos/genética , SARS-CoV-2/imunologia , Vacinas de DNA/imunologia , Vírus Vaccinia/genética , Enzima de Conversão de Angiotensina 2/genética , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos/imunologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/genética , Modelos Animais de Doenças , Expressão Gênica , Humanos , Imunização , Imunização Passiva , Imunoglobulina G/imunologia , Camundongos , Camundongos Transgênicos , Glicoproteína da Espícula de Coronavírus/imunologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética
17.
PLoS One ; 16(3): e0248007, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33750975

RESUMO

More than 65 million people have been confirmed infection with SARS-CoV-2 and more than 1 million have died from COVID-19 and this pandemic remains critical worldwide. Effective vaccines are one of the most important strategies to limit the pandemic. Here, we report a construction strategy of DNA vaccine candidates expressing full length wild type SARS-CoV-2 spike (S) protein, S1 or S2 region and their immunogenicity in mice. All DNA vaccine constructs of pCMVkan-S, -S1 and -S2 induced high levels of specific binding IgG that showed a balance of IgG1/IgG2a response. However, only the sera from mice vaccinated with pCMKkan-S or -S1 DNA vaccines could inhibit viral RBD and ACE2 interaction. The highest neutralizing antibody (NAb) titer was found in pCMVkan-S group, followed by -S1, while -S2 showed the lowest PRNT50 titers. The geometric mean titers (GMTs) were 2,551, 1,005 and 291 for pCMVkan-S, -S1 and -S2, respectively. pCMVkan-S construct vaccine also induced the highest magnitude and breadth of T cells response. Analysis of IFN-γ positive cells after stimulation with SARS-CoV-2 spike peptide pools were 2,991, 1,376 and 1,885 SFC/106 splenocytes for pCMVkan-S, -S1 and -S2, respectively. Our findings highlighted that full-length S antigen is more potent than the truncated spike (S1 or S2) in inducing of neutralizing antibody and robust T cell responses.


Assuntos
Imunidade Humoral , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Células Th1/imunologia , Vacinas de DNA/imunologia , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Anticorpos Neutralizantes/sangue , COVID-19/prevenção & controle , COVID-19/virologia , Citocinas/metabolismo , Feminino , Imunoglobulina G/sangue , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Plasmídeos/genética , Plasmídeos/metabolismo , Ligação Proteica , Células Th1/citologia , Células Th1/metabolismo , Vacinas de DNA/genética
18.
Front Immunol ; 12: 637654, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33732258

RESUMO

A coronavirus SARS-CoV-2, which has caused the pandemic viral pneumonia disease COVID-19, significantly threatens global public health, highlighting the need to develop effective and safe vaccines against its infection. In this study, we developed a novel DNA vaccine candidate against SARS-CoV-2 by expressing a chimeric protein of its receptor-binding domain (RBD) fused to a 33-bp sequence (11 aa) from the hepatitis B virus (HBV) preS1 region with a W4P mutation (W4P-RBD) at the N-terminal region and evaluated its immunogenicity. In vitro transfection experiments in multiple cell lines demonstrated that W4P-RBD vs. wild-type RBD protein (W-RBD) led to enhanced production of IL-6 and TNFα at the transcription and translation levels, suggesting the adjuvant potential of N-terminal HBV preS1 sequences for DNA vaccines against SARS-CoV-2. W4P-RBD also led to enhanced production of IgG and IgA, which can neutralize and block SARS-CoV-2 infection in both blood sera and bronchoalveolar lavage (BAL) fluid from the lung in vaccinated mice. Additionally, W4P-RBD led to an enhanced T-cell-mediated cellular immune response under S1 protein stimulation. In summary, W4P-RBD led to robust humoral and cell-mediated immune responses against SARS-CoV-2 in vaccinated mice, highlighting its feasibility as a novel DNA vaccine to protect against SARS-CoV-2 infection.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Antígenos de Superfície da Hepatite B/genética , Antígenos de Superfície da Hepatite B/imunologia , Mutação , Domínios Proteicos/imunologia , Precursores de Proteínas/genética , Precursores de Proteínas/imunologia , Proteínas Recombinantes de Fusão/imunologia , SARS-CoV-2/imunologia , Vacinas de DNA/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , COVID-19/virologia , Linhagem Celular Tumoral , Chlorocebus aethiops , Células HEK293 , Humanos , Imunogenicidade da Vacina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Vacinação/métodos , Células Vero
19.
J Virol ; 95(9)2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33568510

RESUMO

In this placebo-controlled phase II randomized clinical trial, 103 human immunodeficiency virus type 1 (HIV-1)-infected patients under cART (combined antiretroviral treatment) were randomized 2:1 to receive either 3 doses of DNA GTU-MultiHIV B (coding for Rev, Nef, Tat, Gag, and gp160) at week 0 (W0), W4, and W12, followed by 2 doses of LIPO-5 vaccine containing long peptides from Gag, Pol, and Nef at W20 and W24, or placebo. Analytical treatment interruption (ATI) was performed between W36 to W48. At W28, vaccinees experienced an increase in functional CD4+ T-cell responses (P < 0.001 for each cytokine compared to W0) measured, predominantly against Gag and Pol/Env, and an increase in HIV-specific CD8+ T cells producing interleukin 2 (IL-2) and tumor necrosis factor alpha (TNF-α) (P = 0.001 and 0.013, respectively), predominantly against Pol/Env and Nef. However, analysis of T-cell subsets by mass cytometry in a subpopulation showed an increase in the W28/W0 ratio for memory CD8+ T cells coexpressing exhaustion and senescence markers such as PD-1/TIGIT (P = 0.004) and CD27/CD57 (P = 0.044) in vaccinees compared to the placebo group. During ATI, all patients experienced viral rebound, with the maximum observed HIV RNA level at W42 (median, 4.63 log10 copies [cp]/ml; interquartile range [IQR], 4.00 to 5.09), without any difference between arms. No patient resumed cART for CD4 cell count drop. Globally, the vaccine strategy was safe. However, a secondary HIV transmission during ATI was observed. These data show that the prime-boost combination of DNA and LIPO-5 vaccines elicited broad and polyfunctional T cells. The contrast between the quality of immune responses and the lack of potent viral control underscores the need for combined immunomodulatory strategies. (This study has been registered at ClinicalTrials.gov under registration no. NCT01492985.)IMPORTANCE In this placebo-controlled phase II randomized clinical trial, we evaluated the safety and immunogenicity of a therapeutic prime-boost vaccine strategy using a recombinant DNA vaccine (GTU-MultiHIV B clade) followed by a boost vaccination with a lipopeptide vaccine (HIV-LIPO-5) in HIV-infected patients on combined antiretroviral therapy. We show here that this prime-boost strategy is well tolerated, consistently with previous studies in HIV-1-infected individuals and healthy volunteers who received each vaccine component individually. Compared to the placebo group, vaccinees elicited strong and polyfunctional HIV-specific CD4+ and CD8+ T-cell responses. However, these immune responses presented some qualitative defects and were not able to control viremia following antiretroviral treatment interruption, as no difference in HIV viral rebound was observed in the vaccine and placebo groups. Several lessons were learned from these results, pointing out the urgent need to combine vaccine strategies with other immune-based interventions.


Assuntos
Vacinas contra a AIDS , Antirretrovirais/uso terapêutico , Infecções por HIV/terapia , Vacinas de DNA , Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/imunologia , Adulto , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Infecções por HIV/imunologia , HIV-1/efeitos dos fármacos , Humanos , Imunização Secundária , Masculino , Pessoa de Meia-Idade , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia
20.
Res Vet Sci ; 136: 89-96, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33592449

RESUMO

Although the immunogenicity of DNA vaccines is nonideal, they are still considered as potential alternative vaccine candidates to conventional vaccines. Various DNA delivery systems, including nanoparticles, have been extensively explored and validated to further enhance the immunogenicity of DNA vaccines. DNA vaccines are considered as alternative vaccine candidates. Various DNA delivery systems, including nanoparticles, have been extensively explored to enhance the immunogenicity of DNA vaccines. In this study, positively charged Poly (D, l-lactide-co-glycolic acid) (PLGA) nanoparticles were generated and characterized as a delivery system for O-serotype foot-and-mouth DNA vaccine. A recombinant plasmid encoding swine interleukin (IL)-18, IL-2, or granulocyte-macrophage colony-stimulating factor (GM-CSF) gene was introduced into the DNA vaccine to further improve its immunogenicity, which was evaluated in a guinea pig model. PLGA-pVAX-VP013/IL-18 elicited significantly (P = 0.0149) higher FMDV-specific antibody levels than naked DNA before the challenge. The level of neutralizing antibodies induced by PLGA-pVAX-VP013/IL-18, PLGA-pVAX-VP013/IL-2, and PLGA-pVAX-VP013/GM-CSF significantly increased compared with that induced by naked DNA (P < 0.0001). The lymphocyte proliferation assay showed that cellular immunity induced by PLGA-pVAX-VP013/IL-18 and PLGA-pVAX-VP013/GM-CSF was dramatically enhanced compared with that induced by the inactivated vaccine. The protection by PLGA-pVAX-VP013/IL-18 was consistent with that by the inactivated vaccine post-challenge and was followed by PLGA-pVAX-VP013/GM-CSF. Therefore, cationic PLGA nanoparticles can deliver DNA vaccines and induce humoral and cellular immune responses. The co-administration of FMD DNA vaccine with IL-18 formulated with PLGA nanoparticles was the optimal strategy to improve the immunogenicity of FMD DNA vaccines.


Assuntos
Vírus da Febre Aftosa/imunologia , Imunogenicidade da Vacina , Nanopartículas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/imunologia , Vacinas de DNA/imunologia , Vacinas Virais/imunologia , Animais , Febre Aftosa/imunologia , Febre Aftosa/prevenção & controle , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Cobaias , Interleucina-18/imunologia , Interleucina-2/imunologia , Nanopartículas/administração & dosagem , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/administração & dosagem , Sorogrupo
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