RESUMO
The increasing significance of the aquaculture sector and commercially valuable species underscores the need to develop alternatives for controlling diseases such as Ichthyophthirius multifiliis-induced ichthyophthiriasis. This ciliated protozoan parasite threatens nearly all freshwater fish species, causing substantial losses in the fishery industry. Despite this, effective large-scale treatments are lacking, emphasizing the necessity of adopting preventive strategies. While the pathogenesis of ichthyophthiriasis and its immune stimulation allows for vaccination strategies, precise adjustments are crucial to ensure the production of an effective vaccine compound. Therefore, this study aimed to evaluate the impact of immunizing Astyanax lacustris with a genetic vaccine containing IAG52A from I. multifiliis and the molecular adjuvant IL-8 from A. lacustris. Transcript analysis in immunized A. lacustris indicated mRNA production in fish muscles, demonstrating an expression of this mRNA. Fish were divided into five groups, receiving different vaccine formulations, and all groups received a booster dose 14 days after the initial immunization. Samples from vaccinated fish showed increased IL-1ß mRNA expression in the spleen within 6 h post the second dose and after 14 days. In the head kidney, IL-1ß mRNA expression showed no significant difference at 6 and 24 h but an increase was noted in fish injected with IAG and IAG + IL-8 after 14 days. IL-8 mRNA expression in the spleen and kidney did not significantly differ from the control group. Histological analysis revealed no variation in leukocyte concentration at 6 and 24 h post-vaccination; however, after 14 days, the groups injected with IAG and IAG + IL-8 exhibited a higher leukocyte density at the application sites than the control. The obtained data suggest that the used vaccine is transcribed, indicating its potential to stimulate innate immune response parameters through mRNA cytokine expression and leukocyte migration.
Assuntos
Adjuvantes Imunológicos , Infecções por Cilióforos , Doenças dos Peixes , Hymenostomatida , Vacinas de DNA , Animais , Doenças dos Peixes/prevenção & controle , Doenças dos Peixes/imunologia , Doenças dos Peixes/parasitologia , Infecções por Cilióforos/veterinária , Infecções por Cilióforos/prevenção & controle , Infecções por Cilióforos/imunologia , Hymenostomatida/imunologia , Vacinas de DNA/imunologia , Vacinas de DNA/administração & dosagem , Adjuvantes Imunológicos/administração & dosagem , Vacinação/veterinária , Vacinas Protozoárias/imunologia , Vacinas Protozoárias/administração & dosagem , Characidae/imunologia , Interleucinas/imunologiaRESUMO
BACKGROUND: Vaccines in emergency use are efficacious against COVID-19, yet vaccine-induced prevention against nasal SARS-CoV-2 infection remains suboptimal. METHODS: Since mucosal immunity is critical for nasal prevention, we investigated the efficacy of an intramuscular PD1-based receptor-binding domain (RBD) DNA vaccine (PD1-RBD-DNA) and intranasal live attenuated influenza-based vaccines (LAIV-CA4-RBD and LAIV-HK68-RBD) against SARS-CoV-2. FINDINGS: Substantially higher systemic and mucosal immune responses, including bronchoalveolar lavage IgA/IgG and lung polyfunctional memory CD8 T cells, were induced by the heterologous PD1-RBD-DNA/LAIV-HK68-RBD as compared with other regimens. When vaccinated animals were challenged at the memory phase, prevention of robust SARS-CoV-2 infection in nasal turbinate was achieved primarily by the heterologous regimen besides consistent protection in lungs. The regimen-induced antibodies cross-neutralized variants of concerns. Furthermore, LAIV-CA4-RBD could boost the BioNTech vaccine for improved mucosal immunity. INTERPRETATION: Our results demonstrated that intranasal influenza-based boost vaccination induces mucosal and systemic immunity for effective SARS-CoV-2 prevention in both upper and lower respiratory systems. FUNDING: This study was supported by the Research Grants Council Collaborative Research Fund, General Research Fund and Health and Medical Research Fund in Hong Kong; Outbreak Response to Novel Coronavirus (COVID-19) by the Coalition for Epidemic Preparedness Innovations; Shenzhen Science and Technology Program and matching fund from Shenzhen Immuno Cure BioTech Limited; the Health@InnoHK, Innovation and Technology Commission of Hong Kong; National Program on Key Research Project of China; donations from the Friends of Hope Education Fund; the Theme-Based Research Scheme.
Assuntos
Vacinas contra COVID-19 , COVID-19/prevenção & controle , Imunização Secundária , Vacinas contra Influenza , SARS-CoV-2 , Vacinas de DNA , Administração Intranasal , Animais , COVID-19/genética , COVID-19/imunologia , Vacinas contra COVID-19/genética , Vacinas contra COVID-19/imunologia , Chlorocebus aethiops , Modelos Animais de Doenças , Cães , Feminino , Células HEK293 , Humanos , Imunidade nas Mucosas , Vacinas contra Influenza/genética , Vacinas contra Influenza/imunologia , Células Madin Darby de Rim Canino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacinas de DNA/genética , Vacinas de DNA/imunologia , Células VeroRESUMO
In our previous study, we designed and evaluated the efficacy of six DNA vaccine candidates based on the E protein of Zika virus (ZIKV). To optimize the DNA vaccine, we inoculated C57BL/6 and IFNAR1- mice with the vaccine candidate expressing tandem repeated ZIKV envelope domain III (ED III × 3) doses; 50 µg by intramuscular (IM), jet injection (JET), or electroporation (EP) routes. Results showed that vaccination by all routes induced humoral and cellular immunity. Among them, EP induced robust ZIKV E specific-total IgG and neutralizing antibodies, as well as T cell responses. Additionally, EP showed superior protective efficacy against the ZIKV Brazil strain compared to the IM and JET routes. Finally, in the dose optimization test of EP route, cellular immunity of 50 µg was induced a significant level than other dose groups. These results showed that the EP delivery system enhanced the potential immunogenicity and protective efficacy of DNA vaccines.
Assuntos
Vacinas de DNA/imunologia , Vacinas de DNA/normas , Infecção por Zika virus/prevenção & controle , Zika virus/imunologia , Animais , Anticorpos Neutralizantes/sangue , Brasil , Vias de Administração de Medicamentos , Feminino , Deleção de Genes , Imunidade Celular , Imunidade Humoral , Imunogenicidade da Vacina , Camundongos , Camundongos Endogâmicos C57BL , Receptor de Interferon alfa e beta/genética , Vacinas de DNA/administração & dosagem , Infecção por Zika virus/imunologiaRESUMO
DNA vaccines assisted by electroporation efficiently trigger antitumor cytotoxic CD8+ T cell responses in preclinical cancer models and hold potential for human use. They can be easily engineered to express either tumor-associated self-antigens, which are broadly expressed among tumor patients but also in healthy tissue, or tumor-specific neoantigens, which are uniquely expressed in tumors and differ among patients. Recently, it has been demonstrated that DNA vaccination generates both circulating and tissue-resident compartments of CD8+ T cells, which act concertedly against tumors. Here we describe the steps to obtain and test DNA vaccines against models of self-antigens and neoantigens in mice. It includes the evaluation of effector and memory CD8+ T cell responses, as well as assessing the antitumor potential in vivo using transplantable syngeneic tumor models.
Assuntos
Antígenos de Neoplasias/imunologia , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/imunologia , Especificidade do Receptor de Antígeno de Linfócitos T/imunologia , Vacinas de DNA/imunologia , Transferência Adotiva , Animais , Linfócitos T CD8-Positivos/metabolismo , Vacinas Anticâncer/administração & dosagem , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Imunização , Memória Imunológica , Imunofenotipagem , Camundongos , Neoplasias/imunologia , Neoplasias/terapia , Resultado do Tratamento , Vacinação , Vacinas de DNA/administração & dosagem , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
DNA vaccines have been used as a promising strategy for delivery of immunogenic and immunomodulatory molecules into the host cells. Although, there are some obstacles involving the capability of the plasmid vector to reach the cell nucleus in great number to promote the expected benefits. In order to improve the delivery and, consequently, increase the expression levels of the target proteins carried by DNA vaccines, alternative methodologies have been explored, including the use of non-pathogenic bacteria as delivery vectors to carry, deliver, and protect the DNA from degradation, enhancing plasmid expression.
Assuntos
DNA/genética , Vetores Genéticos/genética , Lactobacillales/genética , Plasmídeos/genética , DNA/imunologia , DNA/isolamento & purificação , Escherichia coli/genética , Técnicas de Transferência de Genes , Vetores Genéticos/administração & dosagem , Vetores Genéticos/imunologia , Vetores Genéticos/isolamento & purificação , Humanos , Plasmídeos/administração & dosagem , Plasmídeos/imunologia , Plasmídeos/isolamento & purificação , Transfecção , Transformação Bacteriana , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética , Vacinas de DNA/imunologiaRESUMO
Lactic acid bacteria comprise a large group of Gram-positive organisms capable of converting sugar into lactic acid. They have been studied due to their therapeutic potential on the mucosal surface. Among the species, Lactococcus lactis is considered the model bacterium and it has been explored as an important vehicle for providing therapeutic molecules and antigens in the mucosa. They can be genetically engineered to produce a variety of molecules as well as deliver heterologous DNA and protein. DNA vaccines consist of the administration of a bacterial plasmid under the control of a eukaryotic promoter encoding the antigen of interest. The resulting proteins are capable of stimulating the immune system, becoming a promising technique for immunization against a variety of tumors and infection diseases and having several advantages compared to conventional nucleic acid delivery methods (such as bioballistic delivery, electroporation, and intramuscular administration).
Assuntos
Sistemas de Liberação de Medicamentos , Técnicas de Transferência de Genes , Lactobacillales , Vacinação/métodos , Vacinas de DNA/administração & dosagem , Administração Intranasal , Administração Sublingual , Animais , Camundongos , Mucosa/imunologia , Vacinas de DNA/genética , Vacinas de DNA/imunologiaRESUMO
Chagas disease caused by the protozoan parasite Trypanosoma cruzi is endemic in 21 Latin American countries and the southern United States and now is spreading into several other countries due to migration. Despite the efforts to control the vector throughout the Americas, currently, there are almost seven million infected people worldwide, causing ~10,000 deaths per year, and 70 million people at risk to acquire the infection. Chagas disease treatment is restricted only to two parasiticidal drugs, benznidazole and nifurtimox, which are effective during the acute and early infections but have not been found to be as effective in chronic infection. No prophylactic or therapeutic vaccine for human use has been communicated at this moment. Here, we evaluate in a mouse model a therapeutic DNA vaccine combining Cruzipain (Cz), a T. cruzi cysteine protease that proved to be protective in several settings, and Chagasin (Chg), which is the natural Cz inhibitor. The DNAs of both antigens, as well as a plasmid encoding GM-CSF as adjuvant, were orally administrated and delivered by an attenuated Salmonella strain to treat mice during the acute phase of T. cruzi infection. The bicomponent vaccine based on Salmonella carrying Cz and Chg (SChg+SCz) was able to improve the protection obtained by each antigen as monocomponent therapeutic vaccine and significantly increased the titers of antigen- and parasite-specific antibodies. More importantly, the bicomponent vaccine triggered a robust cellular response with interferon gamma (IFN-γ) secretion that rapidly reduced the parasitemia during the acute phase and decreased the tissue damage in the chronic stage of the infection, suggesting it could be an effective tool to ameliorate the pathology associated to Chagas disease.
Assuntos
Doença de Chagas/prevenção & controle , Cisteína Endopeptidases/imunologia , Proteínas de Protozoários/imunologia , Vacinas Protozoárias/imunologia , Trypanosoma cruzi/imunologia , Vacinação/métodos , Vacinas de DNA/imunologia , Adjuvantes Imunológicos/administração & dosagem , Administração Oral , Animais , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Doença de Chagas/parasitologia , Modelos Animais de Doenças , Feminino , Imunidade Celular , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Vacinas Protozoárias/administração & dosagem , Salmonella/imunologia , Resultado do Tratamento , Vacinas Atenuadas , Vacinas de DNA/administração & dosagemRESUMO
This article discusses standard and new disruptive strategies in the race to develop an anti-COVID-19 vaccine. We also included new bioinformatic data from our group mapping immunodominant epitopes and structural analysis of the spike protein. Another innovative approach reviewed here is the use of BCG vaccine as priming strategy and/or delivery system expressing SARS-CoV-2 antigens.
Assuntos
Vacina BCG/administração & dosagem , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas de DNA/imunologia , Vacinas Virais/imunologia , Enzima de Conversão de Angiotensina 2/química , Anticorpos Antivirais/imunologia , COVID-19/prevenção & controle , Mapeamento de Epitopos , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/química , Ligação Proteica , Glicoproteína da Espícula de Coronavírus/químicaRESUMO
Most studies evaluating vaccine candidates against visceral leishmaniasis (VL) have used parasite promastigote-expressed antigens; however, Leishmania proteins expressed in the amastigote forms should be considered, since few hours after infection this stage comes into contact with the host immune system and is responsible for the development of the disease. In this context, in the present study, a Leishmania amastigote-specific hypothetical protein, called LiHyJ, was evaluated as a recombinant protein plus saponin as an adjuvant or DNA vaccine to protect against VL. The vaccine effect was evaluated by means of the evaluation of immunological and parasitological analyses performed in BALB/c mice against Leishmania infantum infection. Results showed that rLiHyJ/saponin and DNA LiHyJ induced significantly higher levels of anti-protein and anti-parasite IFN-γ, IL-12, GM-CSF, and IgG2a isotype antibodies, which were associated with a low presence of IL-4 and IL-10. DNA vaccination induced higher IFN-γ production, mainly by CD8+ T cells, while rLiHyJ/saponin stimulated the production of this cytokine, mainly by CD4+ T cells. The parasite load evaluated in distinct organs showed that both immunization schedules significantly reduced organic parasitism, when compared to the controls. Similar results were found in the immunological and parasitological assays when using the recombinant protein or DNA, although the vaccination with rLiHyJ plus saponin induced a slightly higher Th1 response and lower parasite load, when compared to the use of DNA plasmid. The protein also proved to be immunogenic when peripheral blood mononuclear cells of treated VL patients and healthy subjects were in vitro stimulated, since higher IFN-γ and lower IL-4 and IL-10 levels were found in the culture supernatants. In conclusion, LiHyJ should be considered in future studies as a vaccine candidate to protect against VL.
Assuntos
Leishmania/imunologia , Vacinas contra Leishmaniose/imunologia , Vacinas de DNA/imunologia , Adjuvantes Imunológicos/administração & dosagem , Adulto , Animais , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Linfócitos T CD8-Positivos/imunologia , DNA/imunologia , Feminino , Humanos , Leishmania/patogenicidade , Leishmania infantum/imunologia , Leishmaniose Visceral/imunologia , Leucócitos Mononucleares/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Proteínas de Protozoários/imunologia , Proteínas Recombinantes/imunologiaRESUMO
Leishmania infantum pyridoxal kinase (PK) protein was characterized after an immunoproteomics screening performed with the sera from patients suffering visceral leishmaniasis (VL). Since it was recognized by sera of mammalian hosts infected by a viscerotropic Leishmania species, PK could emerge as a new vaccine candidate against disease, due to its antigenicity and immunogenicity. In this context, in the present study, the effects of the immunization using PK were evaluated when administered as a DNA plasmid (pDNAA3/PK) or recombinant protein (rPK) plus saponin. The immune response elicited by both vaccination regimens reduced in significant levels the parasite load in spleen, liver, draining lymph nodes and bone marrow, being associated with the development of Th1-type immune response, which was characterized by high levels of IFN-γ, IL-12, GM-CSF, and specific IgG2a antibody, besides low production of IL-4, IL-10, and protein and parasite-specific IgG1 antibodies. CD8+ T cells were more important in the IFN-γ production in the pDNAA3/PK group, while CD4+ T cells contributed more significantly to production of this cytokine in the rPK/Saponin group. In addition, increased IFN-γ secretion, along with low levels of IL-10, were found when PBMCs from VL patients after treatment and healthy individuals were stimulated with the protein. In conclusion, when administered either as a DNA plasmid or recombinant protein plus adjuvant, PK can direct the immune response towards a Th1-type immune profile, protecting mice against L. infantum challenge; therefore, it can be seen as a promising immunogen against human VL.