18 resultados para Interleukin-1beta

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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Objective: NALP3-inflammasome is an innate mechanism, alternative to type-1 interferon, which is able to recognize nucleic acids and viruses in the cytoplasm and to induce pro-inflammatory response. Here, we hypothesized the involvement of inflammasome in the early defense against HIV-1 and in the full maturation of dendritic cells: for this, we evaluated the response of dendritic cells pulsed with HIV-1 in terms of inflammasome activation in healthy donors. Moreover, inflammasome response to HIV was evaluated in HIV-infected individuals. Design and methods: Monocyte-derived dendritic cells isolated from 20 healthy individuals (HC-DC) and 20 HIV-1-infected patients (HIV-DC) were pulsed with alditrithiol-2-inactivated HIV-1. We then analyzed inflammasome genes expression and interleukin-1 beta (IL-1 beta) secretion. Results: In HC-DC, HIV-1 induced higher NLRP3/NALP3 mRNA expression compared with other inflammasome genes such as NALP1/NLRP1 or IPAF/NLRC4 (P < 0.001). This augmented expression was accompanied by CASP1-increased and IL1B-increased mRNA levels and by a significant increment of IL-1b secretion (P < 0.05). Otherwise, HIV-1 failed to activate inflammasome and cytokine production in HIV-DC. HIV-DC showed an increased NLRP3/NALP3 basal expression, suggesting a chronic inflammatory profile of patients' immune cells. Conclusion: HIV-1 was able to induce a NALP3-inflammasome response in healthy individuals, indicating that this inflammasome could play a role in the first steps of HIV-1 infection; the consequent inflammatory process may be important for directing host immune response against the virus and/or disease progression. HIV-DC seemed to be chronically activated, but unresponsive against pathogens. Our findings could be of interest considering the ongoing research about dendritic cell manipulation and therapeutic strategies for AIDS involving dendritic cell-based immune-vaccines. (C) 2011 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins

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Objective The influence of functional polymorphisms in the genes coding for mannose-binding lectin (MBL) and interleukin-1 receptor antagonist (IL-1ra) on recurrent vulvovaginal candidiasis (RVVC) were examined in an urban Brazilian population. Methods DNA was isolated from buccal swabs of 100 women with RVVC and 100 control women and tested by gene amplification for a single nucleotide polymorphism in codon 54 of the MBL2 gene and for a length polymorphism in intron 2 of the IL1RN gene. Genotype and allele frequencies were compared between groups. Results The frequency of the variant MBL2 B allele, associated with reduced circulating and vaginal MBL concentrations, was 27.0% in RVVC and 8.5% in control women (p < .0001). The MBL2 B, B genotype was present in 12% of RVVC patients and 1% of controls (p = .0025). The IL1RN 2 allele frequency, associated with the highest level of unopposed IL-1 beta activity, was 24.0% in RVVC and 23.4% in controls. The IL1RN genotype distribution was also similar in both groups. Conclusion Carriage of the MBL2 codon 54 polymorphism, but not the IL1RN length polymorphism, predisposes to RVVC in Brazilian women.

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BACKGROUND & AIMS: Homozygous loss of function mutations in interleukin-10 (IL10) and interleukin-10 receptors (IL10R) cause severe infantile (very early onset) inflammatory bowel disease (IBD). Allogeneic hematopoietic stem cell transplantation (HSCT) was reported to induce sustained remission in 1 patient with IL-10R deficiency. We investigated heterogeneity among patients with very early onset IBD, its mechanisms, and the use of allogeneic HSCT to treat this disorder. METHODS: We analyzed 66 patients with early onset IBD (younger than 5 years of age) for mutations in the genes encoding IL-10, IL-10R1, and IL-10R2. IL-10R deficiency was confirmed by functional assays on patients' peripheral blood mononuclear cells (immunoblot and enzyme-linked immunosorbent assay analyses). We assessed the therapeutic effects of standardized allogeneic HSCT. RESULTS: Using a candidate gene sequencing approach, we identified 16 patients with IL-10 or IL-10R deficiency: 3 patients had mutations in IL-10, 5 had mutations in IL-10R1, and 8 had mutations in IL-10R2. Refractory colitis became manifest in all patients within the first 3 months of life and was associated with perianal disease (16 of 16 patients). Extraintestinal symptoms included folliculitis (11 of 16) and arthritis (4 of 16). Allogeneic HSCT was performed in 5 patients and induced sustained clinical remission with a median follow-up time of 2 years. In vitro experiments confirmed reconstitution of IL-10R-mediated signaling in all patients who received the transplant. CONCLUSIONS: We identified loss of function mutations in IL-10 and IL-10R in patients with very early onset IBD. These findings indicate that infantile IBD patients with perianal disease should be screened for IL-10 and IL-10R deficiency and that allogeneic HSCT can induce remission in those with IL-10R deficiency.

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OBJECTIVE: This study aims to evaluate the production of interferon-gamma and interleukin-10 by stimulated peripheral blood mononuclear cells isolated from patients with supraglottic laryngeal cancer before and after surgical treatment. METHODS: Fourteen patients with advanced supraglottic laryngeal cancer were studied. Cultures of peripheral blood mononuclear cells isolated during the preoperative and late postoperative periods were stimulated with concanavalin A and Bacille Calmette-Guerin, and the supernatant concentrations of interferon-gamma and interleukin-10 were measured. RESULTS: For non-stimulated cultures, the interferon-gamma levels produced by the preoperative period and the late postoperative period cultures were lower than the levels produced by the control group cultures. The interferon-gamma levels after stimulation with concanavalin A were higher in the late postoperative period cultures than in the preoperative evaluation cultures. Stimulation with Bacille Calmette-Guerin led to the production of similar levels of interferon-gamma and interleukin-10 by all cultures; thus, stimulation increased the levels of interferon-gamma produced by both the preoperative and postoperative cultures relative to the levels produced by the corresponding unstimulated cultures. CONCLUSION: Patients with advanced supraglottic laryngeal cancer exhibit an in vitro deficiency in interferongamma secretion by mononuclear cells. Stimulated cells seem to recover this function during the postoperative period.

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We investigated whether interleukin-4 (IL-4) is present and capable of reducing inflammatory changes seen in ifosfamide-induced hemorrhagic cystitis. Male Swiss mice were treated with saline or ifosfamide alone or ifosfamide with the classical protocol with mesna and analyzed by changes in bladder wet weight (BWW), macroscopic and microscopic parameters, exudate, and hemoglobin quantification. In other groups, IL-4 was administered intraperitoneally 1 h before ifosfamide. In other experimental groups, C57BL/6 WT (wild type) and C57BL/6 WT IL-4 (-/-) knockout animals were treated with ifosfamide and analyzed for changes in BWW. Quantification of bladder IL-4 protein by ELISA in control, ifosfamide-, and mesna-treated groups was performed. Immunohistochemistry to tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) as well as protein identification by Western blot assay for inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) was carried out on ifosfamide- and IL-4-treated animals. In other experimental groups, antiserum against IL-4 was given 30 min before ifosfamide. In IL-4-treated animals, the severity of hemorrhagic cystitis was significantly milder than in animals treated with ifosfamide only, an effect that was reverted with serum anti-IL-4. Moreover, knockout animals for IL-4 (-/-) exhibit a worse degree of inflammation when compared to C57BL/6 wild type. Exogenous IL-4 also attenuated TNF-alpha, IL-1 beta, iNOS, and COX-2 expressions in ifosfamide-treated bladders. IL-4, an anti-inflammatory cytokine, attenuates the inflammation seen in ifosfamide-induced hemorrhagic cystitis.

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Interleukin-18 (IL-18) and interferon-gamma (IFN-?) exert important functions in both innate and adaptive immune responses against intracellular pathogens and viruses. Previous studies suggested that host genetic factors, including cytokines gene polymorphisms, could be involved in the pathogenesis of human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Thus, we analyzed -137C/G and -607A/C of the IL-18 promoter and +874T/A of the IFN-? in DNA samples from 98 HTLV-1-infected individuals exhibiting or not clinical symptoms and 150 healthy control individuals. The IL-18 promoter -607CC genotype was significantly lower in HTLV-1 asymptomatic carriers (HAC) and HTLV-1-infected individuals (HAC + HAM/TSP) than healthy control group. In contrast, the -607AC genotype was significantly higher in HAC and HTLV-1-infected individuals group compared to the healthy control group. The -137G/-607A IL-18 haplotype was higher in infected group than healthy control group, and the -137C/-607C IL-18 haplotype was increased in the healthy control group compared to the others. Finally, the IFN-? polymorphism analysis showed that the HTLV-1-infected individuals with +874AT genotype presented higher proviral load than +874AA genotype. These data indicate that the IL-18-607AC genotype and -137G/-607A haplotype could be a risk factor for HTLV-1 infection, whereas the protective effect could be conferred by -607CC genotype and -137C/-607C haplotype. Also, the IFN-? could be implicated on the proviral load levels.

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Interleukin-17A (IL-17A) is a proinflamatory cytokine that plays an important role in fighting pathogens at mucosal interfaces, by summoning neutrophils and upregulating cytoplasmatic antimicrobial peptides. So far, the presence of IL-17A in leprosy has not been demonstrated. The expression of IL-17A and related cytokines (IL-6 and IL-23p19) was addressed through RNA extraction and cDNA quantitative amplification in macerated biopsies of active lesions of 48 leprosy patients and 20 fragments of normal skin of individuals. Blood levels of IL-17A, IL-23p19 and IL-6 were determined by ELISA. We found an abrogated mRNA IL-17A response in all biopsies of leprosy patients, as compared with controls. Circulating IL-17A and IL-23p19 were undetectable in both patients and controls, but IL-6 was higher in lepromatous patients. Although at low levels, IL-17A mRNA in lepromatous patients had an inverse linear correlation with bacillary burden. Low expression of IL-17A in patients may be a constitutive genetic feature of leprosy patients or a circumstantial event induced by the local presence of the pathogen, as an escape mechanism.

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Objective: Previously, we identified that the ATC/TTC haplotype formed by polymorphisms in the Interleukin-(IL)8 gene conferred susceptibility to chronic periodontitis (CP). The aim of the study was to investigate whether the IL8 haplotype ATC/TTC was associated with the volume of gingival crevicular fluid (GCF), the concentration of interleukin IL-8 in the GCF, as well as periodontal conditions in patients with CP in comparison to controls without CP. Methods: Seventy-nine individuals (CP: n = 41, controls: n = 38) were grouped according to the presence (susceptible for CP) or absence (not susceptible for CP) of the IL8 ATC/TTC haplotype. After periodontal clinical evaluation, they were subdivided by the presence or absence of CP. GCF was collected from each patient and the IL-8 levels were determined by ELISA. The GCF volume of each subject was measured by means of a calibrated electronic device. Comparisons of means between carriers and non-carriers of the ATC/TTC haplotype were evaluated using the Mann-Whitney test. Linear regression and stepwise linear regression analysis were used to analyse the association of the GCF volume with potential covariates and their contribution for the phenotype. Results: We did not find significant differences of both periodontal conditions and IL-8 concentration in the GCF of patients with the presence or absence of the IL8 ATC/TTC haplotype. However, the GCF volume was significantly higher amongst the patients affected by CP that are absent for the IL8 ATC/TTC haplotype. In addition, linear regression analysis showed a statistically significant association between GCF volume and CP, IL8 haplotype ATC/TTC and IL-8 concentration. Conclusions: The IL8 haplotype of susceptibility to CP was neither associated with IL-8 cytokine levels nor with clinical periodontal parameters. Also, CP, IL8 haplotype and IL-8 concentration showed a positive association with the GCF volume levels in the studied patients. (c) 2012 Published by Elsevier Ltd.

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Adiponectin and interleukin 10 (IL-10) are adipokines that are predominantly secreted by differentiated adipocytes and are involved in energy homeostasis, insulin sensitivity, and the anti-inflammatory response. These two adipokines are reduced in obese subjects, which favors increased activation of nuclear factor kappa B (NF-kappa B) and leads to elevation of pro-inflammatory adipokines. However, the effects of adiponectin and IL-10 on NF-kappa B DNA binding activity (NF-kappa Bp50 and NF-kappa Bp65) and proteins involved with the toll-like receptor (TLR-2 and TLR-4) pathway, such as MYD88 and TRAF6 expression, in lipopolysaccharide-treated 3T3-L1 adipocytes are unknown. Stimulation of lipopolysaccharide-treated 3T3-L1 adipocytes for 24 h elevated IL-6 levels; activated the NF-kappa B pathway cascade; increased protein expression of IL-6R, TLR-4, MYD88, and TRAF6; and increased the nuclear activity of NF-kappa B (p50 and p65) DNA binding. Adiponectin and IL-10 inhibited the elevation of IL-6 levels and activated NF-kappa B (p50 and p65) DNA binding. Taken together, the present results provide evidence that adiponectin and IL-10 have an important role in the anti-inflammatory response in adipocytes. In addition, inhibition of NF-kappa B signaling pathways may be an excellent strategy for the treatment of inflammation in obese individuals. (C) 2011 Elsevier Ltd. All rights reserved.

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Abstract Background Human Papillomavirus, HPV, is the main etiological factor for cervical cancer. Different studies show that in women infected with HPV there is a positive correlation between lesion grade and number of infiltrating macrophages, as well as with IL-10 higher expression. Using a HPV16 associated tumor model in mice, TC-1, our laboratory has demonstrated that tumor infiltrating macrophages are M2-like, induce T cell regulatory phenotype and play an important role in tumor growth. M2 macrophages secrete several cytokines, among them IL-10, which has been shown to play a role in T cell suppression by tumor macrophages in other tumor models. In this work, we sought to establish if IL-10 is part of the mechanism by which HPV tumor associated macrophages induce T cell regulatory phenotype, inhibiting anti-tumor activity and facilitating tumor growth. Results TC-1 tumor cells do not express or respond to IL-10, but recruit leukocytes which, within the tumor environment, produce this cytokine. Using IL-10 deficient mice or blocking IL-10 signaling with neutralizing antibodies, we observed a significant reduction in tumor growth, an increase in tumor infiltration by HPV16 E7 specific CD8 lymphocytes, including a population positive for Granzyme B and Perforin expression, and a decrease in the percentage of HPV specific regulatory T cells in the lymph nodes. Conclusions Our data shows that in the HPV16 TC-1 tumor mouse model, IL-10 produced by tumor macrophages induce regulatory phenotype on T cells, an immune escape mechanism that facilitates tumor growth. Our results point to a possible mechanism behind the epidemiologic data that correlates higher IL-10 expression with risk of cervical cancer development in HPV infected women.

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Background: Fibroblasts are now seen as active components of the immune response because these cells express Toll-like receptors (TLRs), recognize pathogen-associated molecular patterns, and mediate the production of cytokines and chemokines during inflammation. The innate host response to lipopolysaccharide (LPS) from Porphyromonas gingivalis is unusual inasmuch as different studies have reported that it can be an agonist for Toll-like receptor 2 (TLR2) and an antagonist or agonist for Toll-like receptor 4 (TLR4). This study investigates and compares whether signaling through TLR2 or TLR4 could affect the secretion of interleukin (IL)-6, IL-8, and stromal derived factor-1 (SDF-1/CXCL12) in both human gingival fibroblasts (HGF) and human periodontal ligament fibroblasts (HPDLF). Methods: After small interfering RNA-mediated silencing of TLR2 and TLR4, HGF and HPDLF from the same donors were stimulated with P. gingivalis LPS or with two synthetic ligands of TLR2, Pam2CSK4 and Pam3CSK4, for 6 hours. IL-6, IL-8, and CXCL12 mRNA expression and protein secretion were evaluated by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. Results: TLR2 mRNA expression was upregulated in HGF but not in HPDLF by all the stimuli applied. Knockdown of TLR2 decreased IL-6 and IL-8 in response to P. gingivalis LPS, or Pam2CSK4 and Pam3CSK4, in a similar manner in both fibroblasts subpopulations. Conversely, CXCL12 remained unchanged by TLR2 or TLR4 silencing. Conclusion: These results suggest that signaling through TLR2 by gingival and periodontal ligament fibroblasts can control the secretion of IL-6 and IL-8, which contribute to periodontal pathogenesis, but do not interfere with CXCL12 levels, an important chemokine in the repair process.

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Background In human malaria, the naturally-acquired immune response can result in either the elimination of the parasite or a persistent response mediated by cytokines that leads to immunopathology. The cytokines are responsible for all the symptoms, pathological alterations and the outcome of the infection depends on the reciprocal regulation of the pro and anti-inflammatory cytokines. IL-10 and IFN-gamma are able to mediate this process and their production can be affected by single nucleotide polymorphisms (SNPs) on gene of these cytokines. In this study, the relationship between cytokine IL-10/IFN-gamma levels, parasitaemia, and their gene polymorphisms was examined and the participation of pro-inflammatory and regulatory balance during a natural immune response in Plasmodium vivax-infected individuals was observed. Methods The serum levels of the cytokines IL-4, IL-12, IFN-gamma and IL-10 from 132 patients were evaluated by indirect enzyme-linked immunosorbent assays (ELISA). The polymorphism at position +874 of the IFN-gamma gene was identified by allele-specific polymerase chain reaction (ASO-PCR) method, and the polymorphism at position -1082 of the IL-10 gene was analysed by PCR-RFLP (PCR-Restriction Fragment Length Polymorphism). Results The levels of a pro- (IFN-gamma) and an anti-inflammatory cytokine (IL-10) were significantly higher in P. vivax-infected individuals as compared to healthy controls. The IFN-gamma levels in primoinfected patients were significantly higher than in patients who had suffered only one and more than one previous episode. The mutant alleles of both IFN-gamma and IL-10 genes were more frequent than the wild allele. In the case of the IFNG+874 polymorphism (IFN-gamma) the frequencies of the mutant (A) and wild (T) alleles were 70.13% and 29.87%, respectively. Similar frequencies were recorded in IL-10-1082, with the mutant (A) allele returning a frequency of 70.78%, and the wild (G) allele a frequency of 29.22%. The frequencies of the alleles associated with reduced production of both IFN-gamma and IL-10 were high, but this effect was only observed in the production of IFN-gamma. Conclusions This study has shown evidence of reciprocal regulation of the levels of IL-10 and IFN-gamma cytokines in P. vivax malaria, which is not altered by the presence of polymorphism in the IL-10 gene.

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Abstract Background Intestinal ischemia/reperfusion (IR) injury is a serious and triggering event in the development of remote organ dysfunction, from which the lung is the main target. This condition is characterized by intense neutrophil recruitment, increased microvascular permeability. Intestinal IR is also responsible for induction of adult respiratory distress syndrome, the most serious and life-threatening form of acute lung injury. The purpose of this study was to investigate the effect of annexin-A1 protein as an endogenous regulator of the organ remote injury induced by intestinal ischemia/reperfusion. Male C57bl/6 mice were subjected to intestinal ischemia, induced by 45 min occlusion of the superior mesenteric artery, followed by reperfusion. Results The intestinal ischemia/reperfusion evoked a high intensity lung inflammation as indicated by the number of neutrophils as compared to control group. Treatment with annexin-A1 peptidomimetic Ac2-26, reduced the number of neutrophils in the lung tissue and increased its number in the blood vessels, which suggests a regulatory effect of the peptide Ac2-26 in the neutrophil migration. Moreover, the peptide Ac2-26 treatment was associated with higher levels of plasma IL-10. Conclusion Our data suggest that the annexin-A1 peptidomimetic Ac2-26 treatment has a regulatory and protective effect in the intestinal ischemia/reperfusion by attenuation of the leukocyte migration to the lung and induction of the anti-inflammatory cytokine IL-10 release into the plasma. The anti-inflammatory action of annexin-A1 and its peptidomimetic described here may serve as a basis for future therapeutic approach in mitigating inflammatory processes due to intestinal ischemia/reperfusion.

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The objectives of this study were to determine if protein-energy malnutrition (PEM) could affect the hematologic response to lipopolysaccharide (LPS), the interleukin-1β (IL-1β) production, leukocyte migration, and blood leukocyte expression of CD11a/CD18. Two-month-old male Swiss mice were submitted to PEM (N = 30) with a low-protein diet (14 days) containing 4% protein, compared to 20% protein in the control group (N = 30). The total cellularity of blood, bone marrow, spleen, and bronchoalveolar lavage evaluated after the LPS stimulus indicated reduced number of total cells in all compartments studied and different kinetics of migration in malnourished animals. The in vitro migration assay showed reduced capacity of migration after the LPS stimulus in malnourished animals (45.7 ± 17.2 x 10(4) cells/mL) compared to control (69.6 ± 7.1 x 10(4) cells/mL, P ≤ 0.05), but there was no difference in CD11a/CD18 expression on the surface of blood leukocytes. In addition, the production of IL-1β in vivo after the LPS stimulus (180.7 pg·h-1·mL-1), and in vitro by bone marrow and spleen cells (41.6 ± 15.0 and 8.3 ± 4.0 pg/mL) was significantly lower in malnourished animals compared to control (591.1 pg·h-1·mL-1, 67.0 ± 23.0 and 17.5 ± 8.0 pg/mL, respectively, P ≤ 0.05). The reduced expression of IL-1β, together with the lower number of leukocytes in the central and peripheral compartments, different leukocyte kinetics, and reduced leukocyte migration capacity are factors that interfere with the capacity to mount an adequate immune response, being partly responsible for the immunodeficiency observed in PEM.

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OBJECTIVE: This study aims to evaluate the production of interferon-gamma and interleukin-10 by stimulated peripheral blood mononuclear cells isolated from patients with supraglottic laryngeal cancer before and after surgical treatment. METHODS: Fourteen patients with advanced supraglottic laryngeal cancer were studied. Cultures of peripheral blood mononuclear cells isolated during the preoperative and late postoperative periods were stimulated with concanavalin A and Bacille Calmette-Guerin, and the supernatant concentrations of interferon-gamma and interleukin-10 were measured. RESULTS: For non-stimulated cultures, the interferon-gamma levels produced by the preoperative period and the late postoperative period cultures were lower than the levels produced by the control group cultures. The interferon-gamma levels after stimulation with concanavalin A were higher in the late postoperative period cultures than in the preoperative evaluation cultures. Stimulation with Bacille Calmette-Guerin led to the production of similar levels of interferon-gamma and interleukin-10 by all cultures; thus, stimulation increased the levels of interferon-gamma produced by both the preoperative and postoperative cultures relative to the levels produced by the corresponding unstimulated cultures. CONCLUSION: Patients with advanced supraglottic laryngeal cancer exhibit an in vitro deficiency in interferongamma secretion by mononuclear cells. Stimulated cells seem to recover this function during the postoperative period.