145 research outputs found

    Antimycobacterial and cytotoxicity activities of free and liposome-encapsulated 3-(4'-bromo[1,1'-biphenyl-4-yl)-3-(4-bromo-phenyl)-N,N-dimethyl-2-propen-1-amine

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    The antimycobacterial activity of 3-(4'-bromo[1,1'-biphenyl-4-yl)-3-(4-bromo-phenyl)-N,N-dimethyl-2-propen-1-amine (BBAP), free or incorporated in preformed liposomes, on extracellular M. tuberculosis H37Rv was 8 and 25 μM (MIC), respectively. Extracellular antimycobacterial activity was not significantly improved by entrapment of BBAP in liposomes, but there was a 6.1-fold reduction of BBAP cytotoxicity on J774 macrophages. Liposomal BBAP or its free form showed IC50 values of 165 and 27 μM, resulting in a selectivity index (SI=IC50/MIC) of 3.4 and 6.6, respectively. Free BBAP in concentrations from 10 to 80 μM were quite effective in eliminating intracellular M. tuberculosis while liposomal formulation was less effective at these concentrations.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Antimycobacterial and cytotoxicity activities of free and liposome-encapsulated 3-(4'-bromo[1,1'-biphenyl-4-yl)-3-(4-bromo-phenyl)-N,N-dimethyl-2-propen-1-amine

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    Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The antimycobacterial activity of 3-(4'-bromo[1,1'-biphenyl-4-yl)-3-(4-bromo-phenyl)-N,N-dimethyl-2-propen-1-amine (BBAP), free or incorporated in preformed liposomes, on extracellular M. tuberculosis H37Rv was 8 and 25 μM (MIC), respectively. Extracellular antimycobacterial activity was not significantly improved by entrapment of BBAP in liposomes, but there was a 6.1-fold reduction of BBAP cytotoxicity on J774 macrophages. Liposomal BBAP or its free form showed IC50 values of 165 and 27 μM, resulting in a selectivity index (SI=IC50/MIC) of 3.4 and 6.6, respectively. Free BBAP in concentrations from 10 to 80 μM were quite effective in eliminating intracellular M. tuberculosis while liposomal formulation was less effective at these concentrations.334871874Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)CNPq_Brasi

    A DNA vaccine against tuberculosis based on the 65 kDa heat-shock protein differentially activates human macrophages and dendritic cells

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    Abstract\ud \ud \ud \ud Background\ud \ud A number of reports have demonstrated that rodents immunized with DNA vaccines can produce antibodies and cellular immune responses presenting a long-lasting protective immunity. These findings have attracted considerable interest in the field of DNA vaccination. We have previously described the prophylactic and therapeutic effects of a DNA vaccine encoding the Mycobacterium leprae 65 kDa heat shock protein (DNA-HSP65) in a murine model of tuberculosis. As DNA vaccines are often less effective in humans, we aimed to find out how the DNA-HSP65 stimulates human immune responses.\ud \ud \ud \ud Methods\ud \ud To address this question, we analysed the activation of both human macrophages and dendritic cells (DCs) cultured with DNA-HSP65. Then, these cells stimulated with the DNA vaccine were evaluated regarding the expression of surface markers, cytokine production and microbicidal activity.\ud \ud \ud \ud Results\ud \ud It was observed that DCs and macrophages presented different ability to uptake DNA vaccine. Under DNA stimulation, macrophages, characterized as CD11b+/CD86+/HLA-DR+, produced high levels of TNF-alpha, IL-6 (pro-inflammatory cytokines), and IL-10 (anti-inflammatory cytokine). Besides, they also presented a microbicidal activity higher than that observed in DCs after infection with M. tuberculosis. On the other hand, DCs, characterized as CD11c+/CD86+/CD123-/BDCA-4+/IFN-alpha-, produced high levels of IL-12 and low levels of TNF-alpha, IL-6 and IL-10. Finally, the DNA-HSP65 vaccine was able to induce proliferation of peripheral blood lymphocytes.\ud \ud \ud \ud Conclusion\ud \ud Our data suggest that the immune response is differently activated by the DNA-HSP65 vaccine in humans. These findings provide important clues to the design of new strategies for using DNA vaccines in human immunotherapy.We thank Dr. Carlos Rodrigo ZárateBladés for helpful suggestions during the course of the studies. We also thank Mrs. Izaíra T. Brandão and Mrs. Ana P. Masson for technical assistance. This study was supported by grants from Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP), Programa Nacional de DST/AIDS do Ministério da Saúde and Conselho Nacional de Pesquisa (CNPq).We thank Dr. Carlos Rodrigo Zárate-Bladés for helpful suggestions during the course of the studies. We also thank Mrs. Izaíra T. Brandão and Mrs. Ana P. Masson for technical assistance. This study was supported by grants from Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP), Programa Nacional de DST/AIDS do Ministério da Saúde and Conselho Nacional de Pesquisa (CNPq)

    B cells Can Modulate the CD8 Memory T Cell after DNA Vaccination Against Experimental Tuberculosis

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    Abstract\ud \ud \ud \ud Background\ud \ud Although B cells are important as antigen presenting cells (APC) during the immune response, their role in DNA vaccination models is unknown.\ud \ud \ud \ud Methods\ud \ud In this study in vitro and in vivo experiments were performed to evaluate the ability of B cells to protect mice against Mycobacterium tuberculosis challenge.\ud \ud \ud \ud Results\ud \ud \ud In vitro and in vivo studies showed that B cells efficiently present antigens after naked plasmid pcDNA3 encoding M. leprae 65-kDa heat shock protein (pcDNA3-Hsp65) internalization and protect B knock-out (BKO) mice against Mycobacterium tuberculosis infection. pcDNA3-Hsp65-transfected B cells adoptively transferred into BKO mice rescued the memory phenotypes and reduced the number of CFU compared to wild-type mice.\ud \ud \ud \ud Conclusions\ud \ud These data not only suggest that B cells play an important role in the induction of CD8 T cells but also that they improve bacterial clearance in DNA vaccine model.We are thankful to Ana Paula Masson and Izaíra T Brandão for providing the DNA vaccine and recombinant protein. This study was supported by a FAPESP fellowship (05/030873) to LPA.We are thankful to Ana Paula Masson and Izaíra T Brandão for providing the DNA vaccine and recombinant protein. This study was supported by a FAPESP fellowship (05/03087-3) to LPA

    Secondary metabolites from the sponges Aplysina fistularis and Dysidea sp. and the antituberculosis activity of 11-ketofistularin-3

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    The present investigation reports the isolation of aeroplysinin-2, 2-(3,5-dibromo-4-methoxyphenyl)-N,N,N-trimethyletanamonium, 7,9-dibromo-10-hydroxy-8-methoxy-1-oxa-2-azaspiro[4.5]deca-2,6,8-trien-3-carboxylic acid and its methyl ester, 11-oxoaerothionin, aerothionin, 11-keto-12-hydroxyaerothionin, 11-ketofistularin-3 and fistularin-3 from Aplysina fistularis, as well as of furodysinin lactone and 9α,11α-epoxicholest-7-en-3β,5α,6α,10-tetrol-6-acetate from Dysidea sp. Although the extracts of both sponges displayed antituberculosis activity, only 11-ketofistularin-3 isolated from A. fistularis displayed antimycobacterial activity against Mycobacterium tuberculosis H34Rv, with MIC at 16 μg/mL and SI of 40, a result that reinforce that fistularin-3 derivatives are interesting leads for the development of antituberculosis drugs.American Society of Pharmacognosy FoundationFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)BIOTA/FAPESP - BIOprospecTAUSP - PIBIC/CNPqFAPES

    Therapeutic Efficacy of Cintredekin Besudotox (IL13-PE38QQR) in Murine Lung Fibrosis Is Unaffected by Immunity to Pseudomonas aeruginosa Exotoxin A

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    Background: We have previously explored a therapeutic strategy for specifically targeting the profibrotic activity of IL-13 during experimental pulmonary fibrosis using a fusion protein comprised of human IL-13 and a mutated form of Pseudomonas aeruginosa exotoxin A (IL13-PE) and observed that the intranasal delivery of IL13-PE reduced bleomycin-induced pulmonary fibrosis through its elimination of IL-13-responsive cells in the lung. The aim of the present study was to determine whether the presence of an immune response to P. aeruginosa and/or its exotoxin A (PE) would diminish the anti-fibrotic properties of IL13-PE. Methodology/Principal Findings: Fourteen days after P. aeruginosa infection, C57BL/6 mice were injected with bleomycin via the intratracheal route. Other groups of mice received 4 doses of saline or IL13-PE by either intranasal or intraperitoneal application, and were challenged i.t. with bleomycin 28 days later. At day 21 after bleomycin, all mice received either saline vehicle or IL13-PE by the intranasal route and histopatological analyses of whole lung samples were performed at day 28 after bleomycin. Intrapulmonary P. aeruginosa infection promoted a neutralizing IgG2A and IgA antibody response in BALF and serum. Surprisingly, histological analysis showed that a prior P. aeruginosa infection attenuated the development of bleomycin-induced pulmonary fibrosis, which was modestly further attenuated by the intranasal administration of IL13-PE. Although prior intranasal administration of IL13-PE failed to elicit an antibody response, the systemic administration of IL13-PE induced a strong neutralizing antibody response. However, the prior systemic sensitization of mice with IL13-PE did not inhibit the anti-fibrotic effect of IL13-PE in fibrotic mice. Conclusions: Thus, IL13-PE therapy in pulmonary fibrosis works regardless of the presence of a humoral immune response to Pseudomonas exotoxin A. Interestingly, a prior infection with P. aeruginosa markedly attenuated the pulmonary fibrotic response suggesting that the immune elicitation by this pathogen exerts anti-fibrotic effects.National Institutes of Health (NIH)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)NeoPharm, In

    Comparison of different delivery systems of DNA vaccination for the induction of protection against tuberculosis in mice and guinea pigs

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    The great challenges for researchers working in the field of vaccinology are optimizing DNA vaccines for use in humans or large animals and creating effective single-dose vaccines using appropriated controlled delivery systems. Plasmid DNA encoding the heat-shock protein 65 (hsp65) (DNAhsp65) has been shown to induce protective and therapeutic immune responses in a murine model of tuberculosis (TB). Despite the success of naked DNAhsp65-based vaccine to protect mice against TB, it requires multiple doses of high amounts of DNA for effective immunization. In order to optimize this DNA vaccine and simplify the vaccination schedule, we coencapsulated DNAhsp65 and the adjuvant trehalose dimycolate (TDM) into biodegradable poly (DL-lactide-co-glycolide) (PLGA) microspheres for a single dose administration. Moreover, a single-shot prime-boost vaccine formulation based on a mixture of two different PLGA microspheres, presenting faster and slower release of, respectively, DNAhsp65 and the recombinant hsp65 protein was also developed. These formulations were tested in mice as well as in guinea pigs by comparison with the efficacy and toxicity induced by the naked DNA preparation or BCG. The single-shot prime-boost formulation clearly presented good efficacy and diminished lung pathology in both mice and guinea pigs

    Genetic vaccine for tuberculosis (pVAXhsp65) primes neonate mice for a strong immune response at the adult stage

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    Abstract\ud \ud \ud \ud Background\ud \ud Vaccination of neonates is generally difficult due to the immaturity of the immune system and consequent higher susceptibility to tolerance induction. Genetic immunization has been described as an alternative to trigger a stronger immune response in neonates, including significant Th1 polarization. In this investigation we analysed the potential use of a genetic vaccine containing the heat shock protein (hsp65) from Mycobacterium leprae (pVAXhsp65) against tuberculosis (TB) in neonate mice. Aspects as antigen production, genomic integration and immunogenicity were evaluated.\ud \ud \ud \ud Methods\ud \ud Hsp65 message and genomic integration were evaluated by RT-PCR and Southern blot, respectively. Immunogenicity of pVAXhsp65 alone or combined with BCG was analysed by specific induction of antibodies and cytokines, both quantified by ELISA.\ud \ud \ud \ud Results\ud \ud This DNA vaccine was transcribed by muscular cells of neonate mice without integration into the cellular genome. Even though this vaccine was not strongly immunogenic when entirely administered (three doses) during early animal's life, it was not tolerogenic. In addition, pVAXhsp65 and BCG were equally able to prime newborn mice for a strong and mixed immune response (Th1 + Th2) to pVAXhsp65 boosters administered later, at the adult life.\ud \ud \ud \ud Conclusion\ud \ud These results suggest that pVAXhsp65 can be safely used as a priming stimulus in neonate animals in prime-boost similar strategies to control TB. However, priming with BCG or pVAXhsp65, directed the ensuing immune response triggered by an heterologous or homologous booster, to a mixed Th1/Th2 pattern of response. Measures as introduction of IL-12 or GM-CSF genes in the vaccine construct or even IL-4 neutralization, are probably required to increase the priming towards Th1 polarization to ensure control of tuberculosis infection.The authors are grateful to Secretaria da Saúde do Estado de São Paulo for providing BCG and to Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) that supported this study with a grant (Proc. No. 03/06348-7).The authors are grateful to Secretaria da Saúde do Estado de São Paulo for providing BCG and to Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) that supported this study with a grant (Proc. No. 03/063487)

    Empresas participantes do índice carbono eficiente (ICO2) - BM&FBOVESPA : análise comparativa do retorno das ações e sensibilidade ao risco de mercado

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    Comunicação apresentada no XII CNEG – Congresso Nacional de Excelência em Gestão & III INOVARSE – Responsabilidade Social Aplicada , 2016.A presente pesquisa avalia alterações no retorno e na sensibilidade ao risco de mercado das ações das empresas que participam no Índice Carbono Eficiente (ICO2) – BM&FBOVESPA. Utilizou-se na análise o período compreendido entre 2011 a 2013. Para o alcance do objetivo proposto, adotou-se a estratégia metodológica dividida em dois estudos, denominados de Estudo "A" e Estudo “B”. No primeiro estudo, realizou-se uma análise comparativa entre empresas que ingressaram no ICO2 (27) e empresas que não ingressaram (8), utilizando para tanto uma abordagem quantitativa, analítica, com técnicas estatísticas de regressão pelo MQO e em painel. Já em relação ao segundo estudo, fez-se uma análise do grupo de empresas que ingressaram no ICO2 (27), observando o período pré e pós-admissão, cujas técnicas estatísticas utilizadas foram regressão SUR, MQO e em painel. A pesquisa utilizou dados secundários, compostos pelos preços das ações e pontos do Ibovespa, extraídos da base de dados Economática, para cálculo dos retornos. Os resultados evidenciaram que as empresas que ingressaram no ICO2 não apresentaram retornos das ações superiores em comparação ao grupo de empresas que não ingressaram no ICO2, mas apresentaram menor sensibilidade ao risco de mercado do que o grupo de empresas que não ingressaram no índice. Além disso, a análise focada apenas nas empresas que participam do índice não evidenciou uma mudança de comportamento nos retornos e na sensibilidade ao risco de mercado das ações desse grupo de empresas antes e após o ingresso no índice.info:eu-repo/semantics/publishedVersio
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