Navegando por Palavras-chave "Adenovirus"
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- ItemAcesso aberto (Open Access)Development of a prototype immunochromatographic test for rapid diagnosis of respiratory adenovirus infection(Elsevier Brazil, 2017) Paulini, Inarei [UNIFESP]; Siqueira-Silva, Joselma; Thomaz, Luciana; Rocha, Leticia; Harsi, Charlotte; Bellei, Nancy [UNIFESP]; Granato, Celso [UNIFESP]Human adenoviruses comprise an important group of etiologie agents that are responsible for various diseases in adults and children, such as respiratory, ocular, gastroenteric, and urinary infections. In immunocompromised and organ-transplanted individuals, these agents can cause generalized infections. Rapid diagnostic methods for detecting these infectious agents are not widely available.& para;& para;The aim of this work was to produce monoclonal and polyclonal anti-adenovirus antibodies to be used in a rapid diagnostic test for respiratory infections.& para;& para;Adenovirus hexons were satisfactorily purified by ultracentrifugation and chromatography. After virus purification, anti-hexon monoclonal antibodies were produced and characterized, following classical methods. Antibodies were specific for adenoviruses 2,3,5, and 41. The proposed immunochromatographic test was standardized using colloidal gold.& para;& para;The standardization of the rapid test was sufficient to detect adenovirus antigens (in nasopharyngeal lavage samples) with sensitivity of 100% and specificity of 85% when compared to direct immunofluorescence.& para;& para;The immunochromatographic assay prototype was sufficiently sensitive to detect B (3), C (2 and 5), and F (41) adenovirus samples. Although based on preliminary data, the test demonstrated the same performance as direct immunofluorescence, but with the advantage of being a point-of-care test. Further studies are still needed to confirm its effectiveness in clinical practice. (C) 2017 Sociedade Brasueira de Infectologia. Published by Elsevier Editera Ltda.
- ItemEmbargoImunização intranasal com adenovírus contendo o gene da ASP-2 de Trypanosoma cruzi(Universidade Federal de São Paulo, 2022-08-31) Wada, Liana Nanako [UNIFESP]; Vasconcelos, Jose Ronnie Carvalho de [UNIFESP]; Noronha, Isau Henrique [UNIFESP]; http://lattes.cnpq.br/1454835868106892; http://lattes.cnpq.br/2376141137368343; http://lattes.cnpq.br/9173004044048354; Universidade Federal de São Paulo (UNIFESP)A doença de Chagas é uma infecção causada pelo protozoário intracelular T. cruzi, que, estima-se, é responsável por cerca de 7.000 mortes anualmente. A doença é caracterizada por um curso clínico bifásico, apresentando poucos ou nenhum sintoma, podendo evoluir até a morte do hospedeiro. O conhecimento sobre a capacidade das células T CD8+ na lise das células hospedeiras infectadas pelo T. cruzi, possibilitou o desenvolvimento de vacinas que estimulam esse processo, a fim de gerar uma imunização eficaz. A vacinação genética consiste na expressão do gene do antígeno na célula do hospedeiro gerando uma resposta protetora, que, durante a infecção, com a ativação da resposta imune adaptativa, ocasiona o controle da replicação do parasito. Neste processo, os linfócitos T CD8+ são fundamentais no controle da infecção por patógenos intracelulares, como o T. cruzi. É fato consabido que a administração de vacinas por vias mucosas é eficiente em respostas imunes humorais mediadas por células, tanto em tecidos de mucosa quanto em âmbito sistêmico, mas os mecanismos acerca deste tipo de vacinação ainda permanecem em desenvolvimento. Tendo em vista a escassez de fármacos no tratamento da doença, torna-se essencial o desenvolvimento de tecnologias, como, estratégias vacinais contra o T. cruzi que sejam capazes de induzir uma resposta protetora. Considerando as múltiplas vantagens de uma vacinação intranasal, foi elaborado um protocolo de imunização adenoviral contendo o gene ASP-2 para avaliar a proteção de animais desafiados experimentalmente com o T. cruzi. Foi utilizada a linhagem A/Sn descrita como altamente suscetível à infecção para avaliar a proteção ao desafio experimental e resposta imune de células T CD8+ específicas geradas após a imunização. Até o sexagésimo dia de infecção, observamos que todos os animais imunizados via intranasal e via intramuscular com o AdASP-2 tiveram um percentual de sobrevivência completo, ao contrário dos animais que receberam o controle vacinal Adβgal, que sucumbiram à infecção no vigésimo dia. A imunização intranasal com o AdASP-2 protegeu os animais completamente, e, para a nossa surpresa, houve baixa resposta de células T CD8+ específicas em células do baço. Ergue-se, assim, a hipótese da ativação de células T CD8+ em outros compartimentos, como no linfonodo e tecidos de mucosa, ou a possível ativação de outras células presentes no sistema imunológico adaptativo, complementando a resposta contra o T. cruzi. A imunização pela inoculação intranasal foi capaz de proteger os animais do desafio experimental, diminuir a carga parasitária em diferentes tecidos e gerar anticorpos IgG e IgA. Em conjunto com esses resultados, em nossas análises, observamos um aumento no número de células secretoras de anticorpo nos grupos imunizados, indicando que células B estariam contribuindo na resposta imune após a vacinação com o AdASP-2.
- ItemSomente MetadadadosInternational epidemiology of human pre-existing adenovirus (Ad) type-5, type-6, type-26 and type-36 neutralizing antibodies: Correlates of high Ad5 titers and implications for potential HIV vaccine trials(Elsevier B.V., 2010-01-22) Mast, T. Christopher; Kierstead, Lisa; Gupta, Swati B.; Nikas, Alexander A.; Kallas, Esper G. [UNIFESP]; Novitsky, Vladimir; Mbewe, Bernard; Pitisuttithum, Punee; Schechter, Mauro; Vardas, Eftyhia; Wolfe, Nathan D.; Aste-Amezaga, Miguel; Casimiro, Danilo R.; Coplan, Paul; Straus, Walter L.; Shiver, John W.; Merck Res Labs; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP); Harvard Univ; Malawi Coll Med; Mahidol Univ; Universidade Federal do Rio de Janeiro (UFRJ); Univ Witwatersrand; Johns Hopkins Bloomberg Sch Publ HlthReplication-defective adenoviruses have been utilized as candidate HIV vaccine vectors Few studies have described the international epidemiology of pre-existing immunity to adenoviruses We enrolled 1904 participants in a cross-sectional serological survey at seven sites in Africa, Brazil, and Thailand to assess neutralizing antibodies (NA) for adenovirus types Ad5, Ad6, Ad26 and Ad36 Clinical trial samples were used to assess NA titers from the US and Europe the proportions of participants that were negative were 14 8%(Ad5), 31 5%(Ad6),41 2%(Ad26) and 53.6% (Ad36) Adenovirus NA titers varied by geographic location and were higher in non-US and non-European settings, especially Thailand in multivariate logistic regression analysis, geographic setting (non-US and non-European settings) was statistically significantly associated with having higher Ad5 titers, participants from Thailand had the highest odds of having high Ad5 titers (adjusted OR = 3 53,95% CI 224,557) Regardless of location. titers of Ad5NA were the highest and Ad36 NA were the lowest Coincident Ad5/6 titers were lower than either Ad5 or Ad6 titers alone Understanding pre-existing immunity to candidate vaccine vectors may contribute to the evaluation of vaccines in international populations (C) 2009 Published by Elsevier Ltd
- ItemSomente MetadadadosVaccination using melanoma cells treated with p19arf and interferon beta gene transfer in a mouse model: a novel combination for cancer immunotherapy(Springer, 2016) Medrano, Ruan Felipe Vieira; Catani, Joao Paulo Portela; Ribeiro, Aline Hunger; Tomaz, Samanta Lopes [UNIFESP]; Merkel, Christian A.; Costanzi-Strauss, Eugenia; Strauss, Bryan E.Previously, we combined p19(Arf) (Cdkn2a, tumor suppressor protein) and interferon beta (IFN-beta, immunomodulatory cytokine) gene transfer in order to enhance cell death in a murine model of melanoma. Here, we present evidence of the immune response induced when B16 cells succumbing to death due to treatment with p19(Arf) and IFN-beta are applied in vaccine models. Use of dying cells for prophylactic vaccination was investigated, identifying conditions for tumor-free survival. After combined p19(Arf) and IFN-beta treatment, we observed immune rejection at the vaccine site in immune competent and nude mice with normal NK activity, but not in NOD-SCID and dexamethasone immunosuppressed mice (NK deficient). Combined treatment induced IL-15, ULBP1, FAS/APO1 and KILLER/DR5 expression, providing a mechanism for NK activation. Prophylactic vaccination protected against tumor challenge, where markedly delayed progression and leukocyte infiltration were observed. Analysis of primed lymphocytes revealed secretion of TH1-related cytokines and depletion protocols showed that both CD4(+) and CD8(+) T lymphocytes are necessary for immune protection. However, application of this prophylactic vaccine where cells were treated either with IFN-beta alone or combined with p19(Arf) conferred similar immune protection and cytokine activation, yet only the combination was associated with increased overall survival. In a therapeutic vaccine protocol, only the combination was associated with reduced tumor progression. Our results indicate that by harnessing cell death in an immunogenic context, our p19(Arf) and IFN-beta combination offers a clear advantage when both genes are included in the vaccine and warrants further development as a novel immunotherapy for melanoma.