Navegando por Autor "Steiner, Bethina Trevisol"
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Item A candidate vaccine for human visceral leishmaniasis based on a specific T cell epitope-containing chimeric protein protects mice against Leishmania infantum infection.(2020) Lage, Daniela Pagliara; Ribeiro, Patrícia Aparecida Fernandes; Dias, Daniel Silva; Mendonça, Débora Vasconcelos Costa; Ramos, Fernanda Fonseca; Carvalho, Lívia Mendes; Oliveira, Daysiane de; Steiner, Bethina Trevisol; Martins, Vivian Tamietti; Melo, Luísa Helena Perin de; Machado, Amanda Sanchez; Santos, Thaís Teodoro de Oliveira; Tavares, Grasiele de Sousa Vieira; Humbert, Maria Victoria; Coelho, Eduardo Antônio Ferraz; Christodoulides, MyronLeishmaniases are neglected diseases caused by infection with Leishmania parasites and there are currently no prophylactic vaccines. In this study, we designed in silico a synthetic recombinant vaccine against visceral leishmaniasis (VL) called ChimeraT, which contains specific T-cell epitopes from Leishmania Prohibitin, Eukaryotic Initiation Factor 5a and the hypothetical LiHyp1 and LiHyp2 proteins. Subcutaneous delivery of ChimeraT plus saponin stimulated a Th1 cell-mediated immune response and protected mice against L. infantum infection, significantly reducing the parasite load in distinct organs. ChimeraT/saponin vaccine stimulated significantly higher levels of IFN-γ, IL-12, and GM-CSF cytokines by both murine CD4+ and CD8+ T cells, with correspondingly low levels of IL-4 and IL-10. Induced antibodies were predominantly IgG2a isotype and homologous antigen-stimulated spleen cells produced significant nitrite as a proxy for nitric oxide. ChimeraT also induced lymphoproliferative responses in peripheral blood mononuclear cells from VL patients after treatment and healthy subjects, as well as higher IFN-γ and lower IL-10 secretion into cell supernatants. Thus, ChimeraT associated with a Th1 adjuvant could be considered as a potential vaccine candidate to protect against human disease.Item Evaluation of a Leishmania hypothetical protein administered as DNA vaccine or recombinant protein against Leishmania infantum infection and its immunogenicity in humans.(2018) Ribeiro, Patrícia Aparecida Fernandes; Dias, Daniel Silva; Lage, Daniela Pagliara; Costa, Lourena Emanuele; Martins, Vivian Tamietti; Tavares, Grasiele de Sousa Vieira; Mendonça, Débora Vasconcelos Costa; Lima, Mariana Pedrosa; Oliveira, Jamil Silvano de; Steiner, Bethina Trevisol; Ávila, Ricardo Andrez Machado de; Roatt, Bruno Mendes; Chávez Fumagalli, Miguel Angel; Souza, Daniel Menezes; Duarte, Mariana Costa; Teixeira Junior, Antonio Lucio; Coelho, Eduardo Antônio FerrazVisceral leishmaniasis (VL) is a fatal disease when acute and untreated. The treatment against this disease is long and presents toxicity and/or high costs. Moreover, parasite resistance has been increasing. Therefore, alternative control measures to avoid the spread of disease should be considered. It is accepted that the development of the T helper (Th)1 immune response, based on the production of pro-inflammatory cytokines, is required for the control of parasites. Although recombinant protein-based vaccines have been tested against VL, they require supplementation with immune adjuvants. In addition, there is a scarcity of studies that comparatively evaluate the efficacy of the immunogens when administered by different delivery systems in mammalian hosts. In the present study, a Leishmania hypothetical protein, LiHyR, was cloned and evaluated by immunization as a plasmid deoxyribonucleic acid (DNA) vaccine or in a recombinant format plus saponin against Leishmania infantum infection. Results showed that both vaccination regimens induced a Th1 cell-based immunity, since high levels of interferon-gamma (IFN-γ), interleukin (IL)-2, IL-12, granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor alpha (TNF-α) were found, and were associated with the low production of IL-4, IL-10, and anti-parasite immunoglobulin (IgG)1 isotype. In addition, significant reductions in the parasite load were found in the evaluated organs of the DNA LiHyR or rLiHyR/saponin-vaccinated animals. No significant difference was achieved between groups vaccinated with DNA or the recombinant protein. The antigen proved to be also immunogenic in human peripheral blood mononuclear cells (PBMCs) collected from healthy subjects and from untreated and treated VL patients. A higher IgG2 isotype was also found in sera samples of these subjects, thus demonstrating its possible use as a human vaccine. This study demonstrates the protective efficacy of a new Leishmania protein against VL, when it is administered as a DNA vaccine or a recombinant protein plus saponin, and points out its use as a human vaccine against disease.Item Evaluation of the protective efficacy of a Leishmania protein associated with distinct adjuvants against visceral leishmaniasis and in vitro immunogenicity in human cells.(2020) Ribeiro, Patrícia Aparecida Fernandes; Dias, Daniel Silva; Lage, Daniela Pagliara; Mendonça, Débora Vasconcelos Costa; Vale, Danniele Luciana; Ramos, Fernanda Fonseca; Carvalho, Lívia Mendes; Carvalho, Ana Maria Ravena Severino; Steiner, Bethina Trevisol; Roque, Marjorie Coimbra; Silva, João Augusto Oliveira da; Oliveira, Jamil Silvano de; Tavares, Grasiele de Sousa Vieira; Martins, Vivian Tamietti; Chávez Fumagalli, Miguel Angel; Roatt, Bruno Mendes; Moreira, Ricardo Luiz Fontes; Souza, Daniel Menezes; Duarte, Mariana Costa; Oliveira, Mônica Cristina de; Ávila, Ricardo Andrez Machado de; Teixeira Junior, Antonio Lucio; Coelho, Eduardo Antônio FerrazThe treatment against visceral leishmaniasis (VL) presents problems, mainly related to the toxicity and/or high cost of the drugs. In this context, a prophylactic vaccination is urgently required. In the present study, a Leishmania protein called LiHyE, which was suggested recently as an antigenic marker for canine and human VL, was evaluated regarding its immunogenicity and protective efficacy in BALB/c mice against Leishmania infantum infection. In addition, the protein was used to stimulate peripheral blood mononuclear cells (PBMCs) from VL patients before and after treatment, as well as from healthy subjects. Vaccination results showed that the recombinant (rLiHyE) protein associated with liposome or saponin induced effective protection in the mice, since significant reductions in the parasite load in spleen, liver, draining lymph nodes, and bone marrow were found. The parasitological protection was associated with Th1-type cell response, since high IFN-γ, IL-12, and GM-CSF levels, in addition to low IL-4 and IL-10 production, were found. Liposome induced a better parasitological and immunological protection than did saponin. Experiments using PBMCs showed rLiHyE-stimulated lymphoproliferation in treated patients’ and healthy subjects’ cells, as well as high IFN-γ levels in the cell supernatant. In conclusion, rLiHyE could be considered for future studies as a vaccine candidate against VL..Item Leishmania infantum amastin protein incorporated in distinct adjuvant systems induces protection against visceral leishmaniasis.(2020) Ribeiro, Patrícia Aparecida Fernandes; Vale, Danniele Luciana; Dias, Daniel Silva; Lage, Daniela Pagliara; Mendonça, Débora Vasconcelos Costa; Ramos, Fernanda Fonseca; Carvalho, Lívia Mendes; Carvalho, Ana Maria Ravena Severino; Steiner, Bethina Trevisol; Roque, Marjorie Coimbra; Silva, João Augusto Oliveira da; Oliveira, Jamil Silvano de; Tavares, Grasiele de Sousa Vieira; Galvani, Nathália Coral; Martins, Vivian Tamietti; Chávez Fumagalli, Miguel Angel; Roatt, Bruno Mendes; Moreira, Ricardo Luiz Fontes; Souza, Daniel Menezes; Oliveira, Mônica Cristina de; Ávila, Ricardo Andrez Machado de; Teixeira, Antonio Lucio; Coelho, Eduardo Antônio FerrazThe control measures against visceral leishmaniasis (VL) include a precise diagnosis of disease, the treatment of human cases, and reservoir and vector controls. However, these are insufficient to avoid the spread of the disease in specific countries worldwide. As a consequence, prophylactic vaccination could be interesting, although no effective candidate against human disease is available. In the present study, the Leishmania infantum amastin protein was evaluated regarding its immunogenicity and protective efficacy against experimental VL. BALB/c mice immunized with subcutaneous injections of the recombinant protein with or without liposome/saponin (Lip/Sap) as an adjuvant. After immunization, half of the animals per group were euthanized and immunological evaluations were performed, while the others were challenged with L. infantum promastigotes. Forty-five days after infection, the animals were euthanized and parasitological and immunological evaluations were performed. Results showed the development of a Th1-type immune response in rAmastin-Lip and rAmastin-Sap/vaccinated mice, before and after infection, which was based on the production of protein and parasite-specific IFN-γ, IL-12, GM-CSF, and nitrite, as well as the IgG2a isotype antibody. CD4+ T cells were mainly responsible for IFN-γ production in vaccinated mice, which also presented significant reductions in parasitism in their liver, spleen, draining lymph nodes, and bone marrow. In addition, PBMC cultures of treated VL patients and healthy subjects stimulated with rAmastin showed lymphoproliferation and higher IFN-γ production. In conclusion, the present study shows the first case of an L. infantum amastin protein associated with distinct delivery systems inducing protection against L. infantum infection and demonstrates an immunogenic effect of this protein in human cells.Item Liposomal formulation of ChimeraT, a multiple T-cell epitope-containing recombinant protein, is a candidate vaccine for human Visceral Leishmaniasis.(2020) Lage, Daniela Pagliara; Ribeiro, Patrícia Aparecida Fernandes; Dias, Daniel Silva; Mendonça, Débora Vasconcelos Costa; Ramos, Fernanda Fonseca; Carvalho, Lívia Mendes; Steiner, Bethina Trevisol; Tavares, Grasiele de Sousa Vieira; Martins, Vivian Tamietti; Machado, Amanda Sanchez; Silva, João Augusto Oliveira da; Santos, Thaís Teodoro de Oliveira; Freitas, Camila Simões de; Oliveira, Jamil Silvano de; Roatt, Bruno Mendes; Ávila, Ricardo Andrez Machado de; Humbert, Maria Victoria; Christodoulides, Myron; Coelho, Eduardo Antônio FerrazBackground: Leishmaniases are neglected diseases caused by infection with Leishmania parasites and there are no human vaccines in use routinely. The purpose of this study was to examine the immunogenicity of ChimeraT, a novel synthetic recombinant vaccine against visceral leishmaniasis (VL), incorporated into a human-compatible liposome formulation. Methods: BALB/c mice were immunized subcutaneously with ChimeraT/liposome vaccine, ChimeraT/saponin adjuvant, or ChimeraT/saline and immune responses examined in vitro and in vivo. Results: Immunization with the ChimeraT/liposome formulation induced a polarized Th1-type response and significant protection against L. infantum infection. ChimeraT/liposome vaccine stimulated significantly high levels of interferon (IFN)-γ, interleukin (IL)-12, and granulocyte macrophage-colony stimulating factor (GM-CSF) cytokines by both CD4 and CD8 T-cells, with correspondingly lower levels of IL-4 and IL-10 cytokines. Induced antibodies were predominantly IgG2a isotype, and homologous antigen-stimulated spleen cells produced significant nitrite as a proxy for nitric oxide (NO). Furthermore, we examined a small number of treated VL patients and found higher levels of circulating anti-ChimeraT protein IgG2 antibodies, compared to IgG1 levels. Conclusions: Overall, the liposomal formulation of ChimeraT induced a protective Th1-type immune response and thus could be considered in future studies as a vaccine candidate against human VL.