999 resultados para IL-12R


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Leptospirosis is a public health problem worldwide and its etiology remains unclear. Its pathogenesis involves a complex interaction between host and infecting microorganism. The inflammatory reaction that controls the infection process also underscores many pathophysiological events occurring in leptospirosis. We investigated the presence of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in renal tissues by immunohistochemical and histopathological examination in animals experimentally inoculated with Leptospira serovar Canicola. All the tests were carried out 2, 7, 14, 21 or 28 days after inoculation. Although TNF-alpha and IL-6 had been detected in tissues throughout the observation period, these cytokines appeared more intensely during the initial phase of infection. Therefore, both TNF-alpha and IL-6 were associated with the immunopathogenesis of leptospirosis. This profile suggests a high immunocellular response throughout the early infection stages followed by subsequent humoral response.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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We performed a comparative study and evaluated cellular infiltrates and anti-inflammatory cytokine production at different time-points after syngeneic or allogeneic skin transplantation. We observed an early IL-10 production in syngeneic grafts compared with allografts. This observation prompted us to investigate the role of IL-10 in isograft acceptance. For this, we used IL-10 KO and WT mice to perform syngeneic transplantation, where IL-10 was absent in the graft or in the recipient. The majority of syngeneic grafts derived from IL-10 KO donors did not engraft or was only partially accepted, whereas IL-10 KO mice transplanted with skin from WT donors accepted the graft. We evaluated IL-10 producers in the transplanted skin and observed that epithelial cells were the major source. Taken together, our data show that production of IL-10 by donor cells, but not by the recipient, is determinant for graft acceptance and strongly suggest that production of this cytokine by keratinocytes immediately upon transplantation is necessary for isograft survival. J. Leukoc. Biol. 92: 259-264; 2012.

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Objective This study investigated environmental endotoxin exposure during early life, sensitization to aeroallergens, the production of cytokines by LPS-stimulated leukocytes, and the development of a wheezing phenotype in a prospective cohort of infants with high risk of developing allergic diseases. Materials and Methods Eighty-four infants were followed from birth until 30 months of age. We assessed endotoxin concentration in house dust of their homes during the first 6 months of life. At age 30 months they were clinically evaluated to determine the development of wheezing and other clinical events, were skin prick tested, and had blood samples collected for the evaluation of cytokine release by LPS-stimulated peripheral blood mononuclear cells (PBMC). Results The level of endotoxin exposure during early life was not associated with development of a wheezing phenotype. On the other hand a higher incidence of respiratory infections occurred among recurrent wheezing (RW) infants. PBMC from RW children exposed to higher levels of environmental endotoxin (above 50?EU/mg) released less Interleukin (IL)-12p70 and IFN-? compared to the non-RW group. TNF-a, IL-10, IL-4, IL-5, and IL17 production by LPS-stimulated PBMC from RW and non-RW children was equivalent in both groups of environmental endotoxin exposure. Conclusion In this prospective cohort of infants with high risk of developing allergic diseases we observed that RW and non-RW children were exposed to similar levels of endotoxin early in life. LPS-stimulated PBMC from RW infants exposed to higher levels of endotoxin released significantly less IL-12 and IFN-? compared to non-RW infants. Pediatr Pulmonol. 2012. 47:10541060. (C) 2012 Wiley Periodicals, Inc.

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Chagas' disease is a protozoosis caused by Trypanosoma cruzi that frequently shows severe chronic clinical complications of the heart or digestive system. Neurological disorders due to T. cruzi infection are also described in children and immunosuppressed hosts. We have previously reported that IL-12p40 knockout (KO) mice infected with the T. cruzi strain Sylvio X10/4 develop spinal cord neurodegenerative disease. Here, we further characterized neuropathology, parasite burden and inflammatory component associated to the fatal neurological disorder occurring in this mouse model. Forelimb paralysis in infected IL-12p40KO mice was associated with 60% (p<0.05) decrease in spinal cord neuronal density, glutamate accumulation (153%, p<0.05) and strong demyelization in lesion areas, mostly in those showing heavy protein nitrosylation, all denoting a neurotoxic degenerative profile. Quantification of T. cruzi 18S rRNA showed that parasite burden was controlled in the spinal cord of WT mice, decreasing from the fifth week after infection, but progressive parasite dissemination was observed in IL-12p40KO cords concurrent with significant accumulation of the astrocytic marker GFAP (317.0%, p<0.01) and 8-fold increase in macrophages/microglia (p<0.01), 36.3% (p<0.01) of which were infected. Similarly, mRNA levels for CD3, TNF-alpha, IFN-gamma, iNOS, IL-10 and arginase I declined in WT spinal cords about the fourth or fifth week after infection, but kept increasing in IL-12p40KO mice. Interestingly, compared to WT tissue, lower mRNA levels for IFN-gamma were observed in the IL-12p40KO spinal cords up to the fourth week of infection. Together the data suggest that impairments of parasite clearance mechanisms in IL-12p40KO mice elicit prolonged spinal cord inflammation that in turn leads to irreversible neurodegenerative lesions.

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The transcription factor B lymphocyte induced maturation protein-1 (Blimp-1) plays important roles in embryonic development and immunity. Blimp-1 is required for the differentiation of plasma cells, and mice with T cell specific deletion of Blimp-1 (Blimp-1CKO mice) develop a fatal inflammatory response in the colon. Previous work demonstrated that lack of Blimp-1 in CD4(+) and CD8(+) T cells leads to intrinsic functional defects, but little is known about the functional role of Blimp-1 in regulating differentiation of Th cells in vivo and their contribution to the chronic intestinal inflammation observed in the Blimp1CKO mice. In this study, we show that Blimp-1 is required to restrain the production of the inflammatory cytokine IL-17 by Th cells in vivo. Blimp-1CKO mice have greater numbers of IL-17 producing TCR beta(+)CD4(+)cells in lymphoid organs and in the intestinal mucosa. The increase in IL-17 producing cells was not restored to normal levels in wild-type and Blimp-1CKO mixed bone marrow chimeric mice, suggesting an intrinsic role for Blimp-1 in constraining the production of IL-17 in vivo. The observation that Blimp-1 deficient CD4(+) T cells are more prone to differentiate into IL-17(+)/IFN-gamma(+) cells and cause severe colitis when transferred to Rag1-deficient mice provides further evidence that Blimp-1 represses IL-17 production. Analysis of Blimp-1 expression at the single cell level during Th differentiation reveals that Blimp-1 expression is induced in Th1 and Th2 but repressed by TGF-beta in Th17 cells. Collectively, the results described here establish a new role for Blimp-1 in regulating IL-17 production in vivo. The Journal of Immunology, 2012,189: 5682-5693.

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Background: Extracellular matrix homeostasis is strictly maintained by a coordinated balance between the expression of metalloproteinases (MMPs) and their inhibitors. The purpose of this study was to investigate whether the expression of MMP-9, MMP-2 and its specific inhibitors, are expressed in a reproducible, specific pattern and if the profiles are related to prognosis in Bladder Cancer (BC). Methods: MMP-9, MMP-2 and its specific inhibitors expression levels were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) in fresh-frozen malignant tissue collected from 40 patients with BC submitted to transurethral resection of bladder. The control group consisted of normal bladder tissue from five patients who had undergone retropubic prostatectomy to treat benign prostatic hyperplasia. Results: MMP-9 was overexpressed in 59.0 % of patients, and MMP-2, TIMP-1, TIMP-2, MMP-14, RECK and IL-8 was underexpressed in most of the patients. Regarding prognostic parameters we observed that high-grade tumors exhibited significantly higher levels of MMP-9 and IL-8 (p = 0.012, p = 0.003). Invasive tumors (pT1-pT2) had higher expression levels of MMP-9 than superficial tumors (pTa) (p = 0.026). The same was noted for IL-8 that was more expressed by invasive tumors (p = 0.015, p = 0.048). Most importantly tumor recurrence was related with higher levels of both MMP-9 (p = 0.003) and IL-8 (p = 0.005). Conclusion: We have demonstrated that the overexpression of MMP-9 and higher expression of IL-8 are related to unfavorable prognostic factors of urothelial bladder cancer and tumor recurrence and may be useful in the follow up of the patients.

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Objective: Extracellular matrix homeostasis is strictly maintained by a coordinated balance between the expression of metalloproteinases (MMPs) and their regulators. The purpose of this study was to investigate whether MMP-2 and its specific regulators, TIMP-2, MT1-MMP and IL-8, are expressed in a reproducible, specific pattern and if the profiles are related to prognosis and clinical outcome of prostate cancer (PCa). Materials and Methods: MMP-2, TIMP-2, MT1-MMP and IL-8 expression levels were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) in freshly frozen malignant and benign tissue specimens collected from 79 patients with clinically localized PCa who underwent radical prostatectomies. The control group consisted of 11 patients with benign prostate hyperplasia (BPH). The expression profile of the MMP-2 and its regulators were compared using Gleason scores, pathological stage, pre-operative PSA levels and the final outcome of the PCa. Results: The analysis of 79 specimens of PCa revealed that MMP-2, TIMP-2, MT1-MMP and IL-8 were underexpressed at 60.0%, 72.2%, 62.0% and 65.8%, respectively, in malignant prostatic tissue in relation to BPH samples. Considering the prognostic parameters, we demonstrated that high Gleason score tumors (>= 7) over-expressed MMP-2 (p = 0.048) and TIMP-2 (p = 0.021), compared to low Gleason score tumors (< 7). Conclusion: We have demonstrated that MMP-2 and its regulators are underexpressed in PCa. Alternatively, overexpression of MMP-2 and TIMP-2 was related to higher Gleason score tumors. We postulate that alterations in metalloproteinase expression may be important in the control of tissue homeostasis related to prostate carcinogenesis and tumor behavior.

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Interleukin (IL)-1 beta, tumor necrosis factor (TNF)-alpha, and IL-6 have been established as important mediators of fever induced by lipopolysaccharide (LPS) from Gram-negative bacteria. Whether these pro-inflammatory cytokines are also important in mediating fever induced by live bacteria remains less certain. We therefore investigated the following: (1) the synthesis of TNF-alpha, IL-1 beta, and IL-6 during E. coli-induced fever and (2) the effect of blocking the action of cytokines within the brain on E. coli-induced fever. Body or tail skin temperature (bT or Tsk, respectively) was measured by biotelemetry or telethermometry, every 30 min, during 6 or 24 h. Depending on the number of colony-forming units (CFU) injected i.p., administration of E. coli induced a long-lasting increase in bT of male Wistar rats. The duration of fever did not correlate with the number of CFU found in peritoneal cavity or blood. Because 2.5 x 10(8) CFU induced a sustained fever without inducing a state of sepsis/severe infection, this dose was used in subsequent experiments. The E. coli-induced increase in bT was preceded by a decrease in Tsk, reflecting a thermoregulatory response. TNF-alpha, IL-1 beta, and IL-6 were detected at 3 h in serum of animals injected i.p. with E. coli. In the peritoneal exudates, TNF-alpha, IL-1 beta, and IL-6 were detected at 0.5 and 3 h after E. coli administration. Moreover, both IL-1 beta and IL-6, but not TNF-alpha, were found in the cerebrospinal fluid (CSF) and hypothalamus of animals injected with E. coli. Although pre-treatment (i.c.v., 2 mu l, 15 min before) with anti-IL-6 antibody (anti-IL-6, 5 mu g) reduced E. coli-induced fever, pre-treatment with either IL-1 receptor antagonist (IL-1ra, 200 mu g) or soluble TNF receptor I (sTNFRI, 500 ng) had no effect on the fever response. In conclusion, replicating E. coli promotes an integrated thermoregulatory response in which the central action of IL-6, but not IL-1 and TNF, appears to be important.

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Plasmodium chabaudi infection induces a rapid and intense splenic CD4(+) T cell response that contributes to both disease pathogenesis and the control of acute parasitemia. The subsequent development of clinical immunity to disease occurs concomitantly with the persistence of low levels of chronic parasitemia. The suppressive activity of regulatory T (T-reg) cells has been implicated in both development of clinical immunity and parasite persistence. To evaluate whether IL-2 is required to induce and to sustain the suppressive activity of T-reg cells in malaria, we examined in detail the effects of anti-IL-2 treatment with JES6-1 monoclonal antibody (mAb) on the splenic CD4(+) T cell response during acute and chronic P. chabaudi AS infection in C57BL/6 mice. JES6-1 treatment on days 0, 2 and 4 of infection partially inhibits the expansion of the CD4(+)CD25(+)Foxp3(+) cell population during acute malaria. Despite the concomitant secretion of IL-2 and expression of high affinity IL-2 receptor by large CD4(+) T cells, JES6-1 treatment does not impair effector CD4+ T cell activation and IFN-gamma production. However, at the chronic phase of the disease, an enhancement of cellular and humoral responses occurs in JES6-1-treated mice, with increased production of TNF-alpha and parasite-specific IgG2a antibodies. Furthermore, JES6-1 mAb completely blocked the in vitro proliferation of CD4(+) T cells from non-treated chronic mice, while it further increased the response of CD4(+) T cells from JES6-1-treated chronic mice. We conclude that JES6-1 treatment impairs the expansion of T-reg cell population during early P. chabaudi malaria and enhances the Th1 cell response in the late phase of the disease.

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Shiftwork-induced sleep deprivation and circadian disruption probably leads to an increase in the production of cytokines and dysregulation of innate immune system, respectively. This project aims evaluating changes in salivary IL-1 beta, cortisol, and melatonin in night workers. Method. Two day and three night healthy workers participated in this study. Sleep was evaluated by actimetry and activity protocols. Saliva was collected at waking and bedtime the last workday and the following two days-off and was analyzed by ELISA. Results. Neither sleep duration nor efficiency showed any association with salivary IL-1beta. IL-1beta levels were higher at waking than at bedtime during working days for all workers, but only one day and one night-worker maintained this pattern and hormone rhythms during days off. For this night worker, melatonin levels were shifted to daytime. A second one presented clear alterations in IL-1beta and hormone rhythms on days-off. Conclusions. Our preliminary results suggest that night work can disturb the variation pattern of salivary IL-1beta. No association of this variation with sleep was observed. It seems that disruption in hormone rhythms interfere with salivary IL-1beta production. IL-1beta production pattern seems to be maintained when rhythms are present, in spite of a shift in melatonin secretion.

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Intracellular pattern recognition receptors such as the nucleotide-binding oligomerization domain (NOD)-like receptors family members are key for innate immune recognition of microbial infection and may play important roles in the development of inflammatory diseases, including rheumatic diseases. In this study, we evaluated the role of NOD1 and NOD2 on development of experimental arthritis. Ag-induced arthritis was generated in wild-type, NOD1(-/-)!, NOD2(-/-), or receptor-interacting serine-threonine kinase 2(-/-) (RIPK2(-/-)) immunized mice challenged intra-articularly with methylated BSA. Nociception was determined by electronic Von Frey test. Neutrophil recruitment and histopathological analysis of proteoglycan lost was evaluated in inflamed joints. Joint levels of inflammatory cytokine/chemokine were measured by ELISA. Cytokine (IL-6 and IL-23) and NOD2 expressions were determined in mice synovial tissue by RT-PCR. The NOD2(-/-) and RIPK2(-/-), but not NOD1(-/-), mice are protected from Ag-induced arthritis, which was characterized by a reduction in neutrophil recruitment, nociception, and cartilage degradation. NOD2/RIPK2 signaling impairment was associated with a reduction in proinflammatory cytokines and chemokines (TNF, IL-1 beta, and CXCL1/KC). IL-17 and IL-17 triggering cytokines (IL-6 and IL-23) were also reduced in the joint, but there is no difference in the percentage of CD4(+) IL-17(+) cells in the lymph node between arthritic wild-type and NOD2(-/-) mice. Altogether, these findings point to a pivotal role of the NOD2/RIPK2 signaling in the onset of experimental arthritis by triggering an IL-17-dependent joint immune response. Therefore, we could propose that NOD2 signaling is a target for the development of new therapies for the control of rheumatoid arthritis. The Journal of Immunology, 2012, 188: 5116-5122.