Vaccination Using Recombinants Influenza and Adenoviruses Encoding Amastigote Surface Protein-2 Are Highly Effective on Protection against Trypanosoma cruzi Infection

In the present study we evaluated the protection raised by immunization with recombinant influenza viruses carrying sequences coding for polypeptides corresponding to medial and carboxi-terminal moieties of Trypanosoma cruzis amastigote surface protein 2 (ASP2). Those viruses were used in sequential immunization with recombinant adenovirus (heterologous prime-boost immunization protocol) encoding the complete sequence of ASP2 (Ad-ASP2) in two mouse strains (C57BL/6 and C3H/He). the CD8 effector response elicited by this protocol was comparable to that observed in mice immunized twice with Ad-ASP2 and more robust than that observed in mice that were immunized once with Ad-ASP2. Whereas a single immunization with Ad-ASP2 sufficed to completely protect C57BL/6 mice, a higher survival rate was observed in C3H/He mice that were primed with recombinant influenza virus and boosted with Ad-ASP2 after being challenged with T. cruzi. Analyzing the phenotype of CD8+ T cells obtained from spleen of vaccinated C3H/He mice we observed that heterologous prime-boost immunization protocol elicited more CD8+ T cells specific for the immunodominant epitope as well as a higher number of CD8+ T cells producing TNF-alpha and IFN-gamma and a higher mobilization of surface marker CD107a. Taken together, our results suggest that immunodominant subpopulations of CD8+ T elicited after immunization could be directly related to degree of protection achieved by different immunization protocols using different viral vectors. Overall, these results demonstrated the usefulness of recombinant influenza viruses in immunization protocols against Chagas Disease.FIOCRUZ/PDTIS-VacinasConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG)Univ Fed Minas Gerais, Inst Ciencias Biol, Dept Bioquim & Imunol, Belo Horizonte, MG, BrazilUniv Fed Minas Gerais, Inst Ciencias Biol, Dept Microbiol, Belo Horizonte, MG, BrazilUniv Fed Minas Gerais, Inst Ciencias Biol, Dept Morfol, Belo Horizonte, MG, BrazilFiocruz MS, Ctr Pesquisas Rene Rachou, Belo Horizonte, MG, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Ctr Terapia Celular & Mol CTCMol, São Paulo, BrazilUniv Massachusetts, Sch Med, Dept Med, Div Infect Dis & Immunol, Worcester, MA USAUniversidade Federal de São Paulo, Escola Paulista Med, Ctr Terapia Celular & Mol CTCMol, São Paulo, BrazilCNPq: 015/2008CNPq: 064/2008Web of Scienc

Disrupted iron metabolism and mortality during co-infection with malaria and an intestinal gram-negative extracellular pathogen

Individuals with malaria exhibit increased morbidity and mortality when infected with Gram-negative (Gr−) bacteria. To explore this experimentally, we performed co-infection of mice with Plasmodium chabaudi and Citrobacter rodentium, an extracellular Gr− bacterial pathogen that infects the large intestine. While single infections are controlled effectively, co-infection results in enhanced virulence that is characterized by prolonged systemic bacterial persistence and high mortality. Mortality in co-infected mice is associated with disrupted iron metabolism, elevated levels of plasma heme, and increased mitochondrial reactive oxygen species (ROS) production by phagocytes. In addition, iron acquisition by the bacterium plays a key role in pathogenesis because co-infection with a mutant C. rodentium strain lacking a critical iron acquisition pathway does not cause mortality. These results indicate that disrupted iron metabolism may drive mortality during co-infection with C. rodentium and P. chabaudi by both altering host immune responses and facilitating bacterial persistence

A importância do diagnóstico precoce da Síndrome de Li- Fraumeni em pacientes com história familiar significativa de Câncer: uma revisão integrativa da literatura

Introdução: A síndrome de Li Fraumeni é uma síndrome de predisposição ao câncer transmitida de forma autossômica dominante, decorrente em sua grande maioria de uma mutação no gene supressor de tumor TP53 localizado no éxon do braço curto do cromossomo 17, o qual possui função importante na regulação do ciclo celular e no controle da apoptose. Dessa forma, as mutações herdadas em tal gene resultam em uma divisão celular descontrolada e, consequentemente, em múltiplas neoplasias primárias. Os portadores da síndrome de Li Fraumeni apresentam alto risco de desenvolverem câncer, apresentando relação com diversos tumores malignos, como sarcoma, leucemia, câncer de mama e tumores do sistema nervoso central. Objetivo: Avaliar a importância do diagnóstico precoce da síndrome de Li-Fraumeni em pacientes com histórico familiar de câncer, de modo que o diagnóstico prévio da mutação propicie o aumento da sobrevida dos indivíduos portadores, maior chance de prevenção contra o aparecimento de tumores e maior eficácia dos tratamentos. Método: Foi realizado um levantamento nas bases de dados PubMed, SciELO e Google acadêmico. Usaram-se descritores relacionados a síndrome de Li-Fraumeni e o diagnóstico precoce, em português e inglês. Resultados: Os objetivos e resultados foram ordenados e apresentados em uma tabela. Conclusão: O diagnóstico precoce com a detecção da mutação através do teste genético são de suma importância para a garantia de uma maior longevidade e qualidade de vida para os portadores através do acompanhamento médico e medidas de rastreamento. O acompanhamento a longo prazo com a realização de medidas preventivas e exames como ressonâncias magnéticas periodicamente podem detectar tumores em estágio inicial, facilitando o tratamento

Cell phenotypes as activity biomarkers in patients with Systemic Lupus Erythematosus

The pathogenesis of systemic lupus erythematosus (SLE) is complex. Few studies in Brazilian population have addressed cell phenotypes associated with immunological responses and their associations with SLE activity. The aim of this study is to investigate cell phenotypes associated to SLE diagnosis, treatment and activity. Twenty-eight SLE female patients (17 inactive, 11 active) and 10 healthy women were included in this study. Markers of natural killer (Nk), T and B cells in peripheral blood were evaluated by flow cytometry. Nkt cells were decreased only in SLE active patients. Activated CD4+, regulatory T FoxP3+ and B cells were decreased in both active and inactive SLE patients, compared to control group. The data corroborate the disruption of immune regulatory response in SLE patients and suggest phenotipic changes as possible biomarkers of SLE activity

Estabelecimento de uma nova terapia antitumoral utilizando parasito transgênico expressando NY-ESO-1 associado ao bloqueio de CTLA-4

Exportado OPUSMade available in DSpace on 2019-08-12T15:02:42Z (GMT). No. of bitstreams: 1 tesefinal_luara.pdf: 15589474 bytes, checksum: c1c088305d98a6819fe2df314eca8502 (MD5) Previous issue date: 8O desenvolvimento da imunoterapia contra o câncer é um grande desafio. Embora vários estudos clínicos resultaram no desenvolvimento de resposta imune mensuráveis, apenas uma minoria dos pacientes obtiveram beneficio clínico, tal como a regressão tumoral. A utilização de uma cepa atenuada do Trypanosoma cruzi (CL-14) como vetor vacinal expressando o antígeno cancer testis NY-ESO-1 (CL-14-NY-ESO-1), proposta pelo nosso grupo, foi capaz de prevenir o crescimento do tumor em um modelo profilático. Neste trabalho nós elucidamos que o CL-14-NY-ESO-1 promove a formação de ambos linfócitos T CD8+ de memória efetora e efetores, que impedem eficazmente o desenvolvimento do tumor. Além disso, o melhor prognóstico correlaciona com a alta produção das citocinas IFN- e IL-2 e a presença de maior número de células específicas contra o tumor, inclusive células com perfil citotóxico. No entanto, o efeito terapêutico de tal vacina é bastante limitado. A fim de prolongar a resposta efetora induzida pelo CL-14-NY-ESO-1 nós propomos, em um protocolo terapêutico, o bloqueio dos sinais inibitórios mediados pelo Antígeno Associado ao Linfócito T citotóxico-4 (CTLA-4). Os resultados demonstram o aumento da frequência das células T CD8+ específicas contra o tumor, das células T produtoras de IFN- e ainda a promoção da migração dos linfócitos para o infiltrado tumoral. Como resultado, a terapia com CL-14-NYESO- 1 associado com o anti-CTLA-4 é altamente eficaz no controle do desenvolvimento de melanoma em curso.The development of immunotherapy for cancer has long been a challenge. Although multiple clinical trials have resulted in the development of measurable immune responses only a minority of patients has experienced clinical benefit, such as tumor regression. The use of a transgenic attenuated Trypanosoma cruzi strain (CL-14) as a vaccine vector expressing the cancer testis antigen NY-ESO-1 (CL-14-NY-ESO-1), proposed by our group, was able to prevent tumor growth in a vaccine model. Here we report that CL-14-NY-ESO-1 induces both memory effector and effector CD8+ T lymphocytes that efficiently prevent tumor development. Additionally, the better prognosis correlates with the high production of cytokines IFN- and IL-2 and the presence of greater numbers of specific cells against tumor including cells with cytotoxic profile. However, the therapeutic effect of such vaccine is rather limited. To increase T cell response induced by transgenic parasite we propose, in therapeutic protocol, the blockade of inhibitory signals mediated by Cytotoxic T Lymphocyteassociated Antigen 4 (CTLA-4). The results show the enhanced of the frequency of NY-ESO- 1-specific effector CD8+ T cells producing IFN-, and promote lymphocyte migration to the tumor infiltrate. As a result, therapy with CL-14-NY-ESO-1 associated with anti-CTLA-4 is highly effective in controlling the development of an ongoing melanoma

Vaccination Using Recombinants Influenza and Adenoviruses Encoding Amastigote Surface Protein-2 Are Highly Effective on Protection against Trypanosoma cruzi Infection

In the present study we evaluated the protection raised by immunization with recombinant influenza viruses carrying sequences coding for polypeptides corresponding to medial and carboxi-terminal moieties of Trypanosoma cruzi ´s amastigote surface protein 2 (ASP2). Those viruses were used in sequential immunization with recombinant adenovirus (heterologous prime-boost immunization protocol) encoding the complete sequence of ASP2 (Ad-ASP2) in two mouse strains (C57BL/6 and C3H/He). The CD8 effector response elicited by this protocol was comparable to that observed in mice immunized twice with Ad-ASP2 and more robust than that observed in mice that were immunized once with Ad-ASP2. Whereas a single immunization with Ad-ASP2 sufficed to completely protect C57BL/6 mice, a higher survival rate was observed in C3H/He mice that were primed with recombinant influenza virus and boosted with Ad-ASP2 after being challenged with T. cruzi. Analyzing the phenotype of CD8+ T cells obtained from spleen of vaccinated C3H/He mice we observed that heterologous prime-boost immunization protocol elicited more CD8+ T cells specific for the immunodominant epitope as well as a higher number of CD8+ T cells producing TNF-α and IFN-γ and a higher mobilization of surface marker CD107a. Taken together, our results suggest that immunodominant subpopulations of CD8+ T elicited after immunization could be directly related to degree of protection achieved by different immunization protocols using different viral vectors. Overall, these results demonstrated the usefulness of recombinant influenza viruses in immunization protocols against Chagas Disease.status: publishe

Oxidized Multiwalled Carbon Nanotubes as Antigen Delivery System to Promote Superior CD8⁺ T Cell Response and Protection against Cancer

Properties like high interfacial area with cellular membranes, unique ability to incorporate multiple functionalization, as well as compatibility and transport in biological fluids make carbon nanotubes (CNTs) useful for a variety of therapeutic and drug-delivery applications. Here we used a totally synthetic hybrid supramolecule as an anticancer vaccine formulation. This complex structure comprises CNTs as delivery system for the Cancer Testis Antigen named NY-ESO-1, allied to a synthetic Toll-Like Receptor agonist. The CNT constructs were rapidly internalized into dendritic cells, both in vitro and in vivo, and served as an intracellular antigen depot. This property favored the induction of strong CD4⁺ T as well as CD8⁺ T cell-mediated immune responses against the NY-ESO-1. Importantly, the vaccination significantly delayed the tumor development and prolonged the mice survival, highlighting the potential application of CNTs as a vaccine delivery system to provide superior immunogenicity and strong protection against cancer

Oxidized Multiwalled Carbon Nanotubes as Antigen Delivery System to Promote Superior CD8⁺ T Cell Response and Protection against Cancer

Properties like high interfacial area with cellular membranes, unique ability to incorporate multiple functionalization, as well as compatibility and transport in biological fluids make carbon nanotubes (CNTs) useful for a variety of therapeutic and drug-delivery applications. Here we used a totally synthetic hybrid supramolecule as an anticancer vaccine formulation. This complex structure comprises CNTs as delivery system for the Cancer Testis Antigen named NY-ESO-1, allied to a synthetic Toll-Like Receptor agonist. The CNT constructs were rapidly internalized into dendritic cells, both in vitro and in vivo, and served as an intracellular antigen depot. This property favored the induction of strong CD4⁺ T as well as CD8⁺ T cell-mediated immune responses against the NY-ESO-1. Importantly, the vaccination significantly delayed the tumor development and prolonged the mice survival, highlighting the potential application of CNTs as a vaccine delivery system to provide superior immunogenicity and strong protection against cancer

Cellular responses to immunodominant epitopes from ASP2 in mice immunized with recombinant viruses.

<p>C57BL/6 and C3H/He mice were immunized as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0061795#s2" target="_blank">Material and Methods</a>. Three weeks after the boost immunization, the presence of ASP-2 specific IFN-γ producing T cells in spleen cells of C57BL/6 (A) or C3H/He (B) mice were assessed by ELISPOT and culture supernatant ELISA (n = 8). To this aim, the spleen cells of individual mice were stimulated 18 hours (ELISPOT) or 72 hours (ELISA) <i>ex vivo</i> with VNHRFTLV (aa 553–560; for C57BL/6) or TEWETGQI (aa 320–327; for C3H/He) specific ASP2 peptides. Optical Density (OD) was measured at 450 nm.</p

Immunization Schedule and Induction of specific anti-ASP2 humoral immune response in mice vaccinated with recombinant viruses.

<p>Timeline representation of immunization schedule and experimental procedures (A). C57BL/6 mice were immunized as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0061795#s2" target="_blank">Material and Methods</a>. Two weeks after the boost immunization, the animals were bled and the presence of specific anti-ASP2 total IgG antibodies in mice sera was evaluated by western by incubating individual (lanes 1–9) or pooled (lanes 10 and 11) sera of C57BL/6 mice with nitrocellulose membranes loaded with recombinant ASP2 protein (His65KDa) as capture antigen blot (B). Alternatively, the antibodies levels were measured by ELISA using individual sera of C5BL/6 (C) or C3H/He (D) mice sera diluted 1∶100 and recombinant ASP2 protein as capture antigen. Optical Density (OD) was measured at 450 nm.</p