974 resultados para TH1 cytokines


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We previously reported that a DNA vaccine constructed with the heat shock protein (HSP65) gene from Mycobacterium leprae (DNA-HSP65) was protective and also therapeutic in experimental tuberculosis. By the intramuscular route, this vaccine elicited a predominant Th1 response that was consistent with its protective efficacy against tuberculosis. It has been suggested that the immune response to Hsp60/65 may be the link between exposure to microorganisms and increased cardiovascular risk. Additionally, the high cholesterol levels found in atherosclerosis could modulate host immunity. In this context, we evaluated if an atherogenic diet could modulate the immune response induced by the DNA-HSP65 vaccine. C57BL/6 mice (4-6 animals per group) were initially submitted to a protocol of atherosclerosis induction and then immunized by the intramuscular or intradermal route with 4 doses of 100 µg DNA-HSP65. on day 150 (15 days after the last immunization), the animals were sacrificed and antibodies and cytokines were determined. Vaccination by the intramuscular route induced high levels of anti-Hsp65 IgG2a antibodies, but not anti-Hsp65 IgG1 antibodies and a significant production of IL-6, IFN-g and IL-10, but not IL-5, indicating a Th1 profile. Immunization by the intradermal route triggered a mixed pattern (Th1/Th2) characterized by synthesis of anti-Hsp65 IgG2a and IgG1 antibodies and production of high levels of IL-5, IL-6, IL-10, and IFN-g. These results indicate that experimentally induced atherosclerosis did not affect the ability of DNA-HSP65 to induce a predominant Th1 response that is potentially protective against tuberculosis.

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Although clove possesses several biological and therapeutic properties, its immunomodulatory action has not been fully investigated. The goal of this work was to investigate the effect of administration of the water extract of clove over a short-term to BALB/c mice on Th1 (IFN-gamma and IL-2) and Th2 (IL-4 and IL-10) cytokine production. After treatment, spleen cells were aseptically removed and cells were stimulated with concanavalin A. Supernatants of cell cultures were used for cytokine determination by ELISA. The chemical composition of the extract was also carried out, revealing that eugenol(4-allyl-2-methoxyphenol) was the major component in our sample. Although the anti-inflammatory action of clove has been mentioned, our data showed that clove administration to mice did not influence the Th1/Th2 cytokine balance. Further studies dealing with cytokine expression and production will provide a better understanding of clove's immunomodulatory and anti-inflammatory actions, using different extract concentrations and different intake periods.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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O objetivo do presente estudo foi comparar a produção de IFN-γ, IL-12 e IL-4 entre camundongos jovens (5, 12 e 19 dias de idade) e adultos (30 dias de idade). As avaliações foram feitas por estimulação, in vitro, de células esplênicas com Concanavalina A (ConA) , Staphylococcus aureus (S. aureus) e lipopolissacarídeo (LPS). Diferentes concentrações de cada estímulo foram testadas e os sobrenadantes das culturas foram coletados após 48 horas de incubação e as concentrações de IFN-γ, IL-12 e IL-4 determinadas por ELISA. Células de camundongos jovens e adultos produziram níveis igualmente elevados de IFN-γ após estímulo com ConA. Somente animais adultos produziram IFN-γ em resposta ao estímulo com S. aureus. Em culturas estimuladas com LPS, a produção desta citocina foi baixa e similar nos animais jovens e significativamente elevada nos animais adultos. Somente células de animais adultos estimuladas com S. aureus foram capazes de produzir IL-12. O único estímulo capaz de induzir níveis detectáveis de IL-4 foi ConA, sendo que estes níveis foram mais elevados nos animais com 12 e 19 dias de idade em comparação com animais neonatos e adultos. A diminuição das doses ótimas dos estímulos não mudou o perfil de produção de cada citocina nos animais jovens. Estes resultados permitem concluir que a idade afeta a produção de citocinas: ocorre maior produção de IL-4 em camundongos jovens e maior produção de IL-12 e IFN-γ em animais adultos. Estas informações são importantes devido ao papel destas citocinas na polarização das respostas imunes nos sentidos Th1 e Th2. Palavras-chave: camundongo; citocina; interferon-gama; interleucina-4; interleucina-12.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Pós-graduação em Biociências e Biotecnologia Aplicadas à Farmácia - FCFAR

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A hanseníase é uma doença infecto-contagiosa, de evolução lenta e progressiva, com grande incidência e prevalência nos estados que compõem a Amazônia legal onde o Pará ocupa lugar de destaque no número de casos no contexto nacional. A fim de se avaliar o perfil de citocinas e a atividade de macrófagos nas formas polares da hanseníase e correlacionar com os seus aspectos histopatológicos, foi realizado um estudo transversal com uma amostra composta por 29 pacientes portadores de uma das formas polares da hanseníase, tuberculoide ou virchowiana, dos quais foram colhidas biópsias de pele de lesões hansênicas. Pode-se observar, através da análise imonoistoquímica deste material que os grupos estudados não apresentaram diferença significativa quanto aos níveis de IL-10, TGF-β, CD68, iNOS e Lisozima. Os níveis de IL-4 não foram expressivos nos tecidos analisados e os níveis de IFN-γ foram maiores nos pacientes do grupo MHV. No polo virchowiano todas as citocinas tiveram uma tendência a uma correlação negativa com a atividade de macrófagos, no polo tuberculoide a IL-10 apresentou uma tendência à correlação negativa com os níveis de iNOS, IFN-γ e lisozima, evidenciando uma inibição da atividade macrofágica por esta citocina. Pode-se concluir que não há diferença na expressão de citocinas de perfil TH1 e TH2 nas formas polares da doença de Hansen e as citocinas apresentam uma tendência a correlação negativa com a atividade de macrófagos no pólo MHV e uma tendência a correlação positiva no pólo MHT. Novas pesquisas são necessárias para esclarecer como populações apresentam mais susceptibilidade à hanseníase que outras, um estudo semelhante com um maior número de indivíduos poderá ter resultados mais expressivos.

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Objective: The aim of this study was to evaluate the effect of carbohydrate or glutamine supplementation, or a combination of the two, on the immune system and inflammatory parameters after exercise in simulated hypoxic conditions at 4500 m.Methods: Nine men underwent three sessions of exercise at 70% VO2(peak) until exhaustion as follows: 1) hypoxia with a placebo; 2) hypoxia with 8% maltodextrin (200 mL/20 min) during exercise and for 2 h after; and 3) hypoxia after 6 d of glutamine supplementation (20 g/d) and supplementation with 8% maltodextrin (200 mL/20 min) during exercise and for 2 h after. All procedures were randomized and double blind. Blood was collected at rest, immediately before exercise, after the completion of exercise, and 2 h after recovery. Glutamine, cortisol, cytokines, glucose, heat shock protein-70, and erythropoietin were measured in serum, and the cytokine production from lymphocytes was measured.Results: Erythropoietin and interleukin (IL)-6 increased after exercise in the hypoxia group compared with baseline. IL-6 was higher in the hypoxia group than pre-exercise after exercise and after 2 h recovery. Cortisol did not change, whereas glucose was elevated post-exercise in the three groups compared with baseline and pre-exercise. Glutamine increased in the hypoxia + carbohydrate + glutamine group after exercise compared with baseline. Heat shock protein-70 increased post-exercise compared with baseline and pre-exercise and after recovery compared with pre-exercise, in the hypoxia carbohydrate group. No difference was observed in IL-2 and IL-6 production from lymphocytes. IL-4 was reduced in the supplemented groups.Conclusion: Carbohydrate or glutamine supplementation shifts the T helper (Th)1/Th2 balance toward Th1 responses after exercise at a simulated altitude of 4500 m. The nutritional strategies increased in IL-6, suggesting an important anti-inflammatory effect. (C) 2014 Elsevier Inc. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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American tegumentary leishmaniasis (ATL) is a disease whose clinical features are strongly related to the type of immune response it induces. Herein we report an atypical presentation of cutaneous leishmaniasis in a woman with a severe and extensive sore located in her leg, and we describe the differences between the usual local immune response in ATL and the local immune response in this patient. We observed an intense inflammatory response characterized by Th1 cells and cytokines with conspicuous expression of Toll-like receptor 3 (TLR-3). Few parasites were present, but there was an extensive tissue damage. We also discuss the immunological factors that could be related to the atypical presentation.

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Background: Leishmania (Viannia) shawi parasite was first characterized in 1989. Recently the protective effects of soluble leishmanial antigen (SLA) from L. (V.) shawi promastigotes were demonstrated using BALB/c mice, the susceptibility model for this parasite. In order to identify protective fractions, SLA was fractionated by reverse phase HPLC and five antigenic fractions were obtained. Methods: F1 fraction was purified from L. (V.) shawi parasite extract by reverse phase HPLC. BALB/c mice were immunized once a week for two consecutive weeks by subcutaneous routes in the rump, using 25 mu g of F1. After 1 and 16 weeks of last immunization, groups were challenged in the footpad with L. (V.) shawi promastigotes. After 2 months, those same mice were sacrificed and parasite burden, cellular and humoral immune responses were evaluated. Results: The F1 fraction induced a high degree of protection associated with an increase in IFN-gamma, a decrease in IL-4, increased cell proliferation and activation of CD8(+)T lymphocytes. Long-term protection was acquired in F1-immunized mice, associated with increased CD4(+) central memory T lymphocytes and activation of both CD4+ and CD8(+) T cells. In addition, F1-immunized groups showed an increase in IgG2a levels. Conclusions: The inductor capability of antigens to generate memory lymphocytes that can proliferate and secrete beneficial cytokines upon infection could be an important factor in the development of vaccine candidates against American Tegumentary Leishmaniasis.