Interleukin-15 increases Paracoccidioides brasiliensis killing by human neutrophils

Interleukin-15 is a pro-inflammatory cytokine produced by a wide range of different cell types, especially monocytes and macrophages, in response to infective agents, playing a crucial and modulatory role in innate and adaptive immune response. Infections by intracellular microorganisms such as some bacteria, protozoa and fungi point out the role of IL-15 in the activation of monocytes/macrophages and neutrophils, a process that represents an important defense mechanism in early periods of infection during the development of innate immune response. The aims of the present study were to evaluate the effects of IL-15 on human neutrophil fungicidal activity against a high virulent Paracoccidioides brasiliensis strain ( Pb18) and to verify whether this activity was mediated by oxidative metabolism such as the production of superoxide anion and H2O2 and if it was associated with an alteration of cytokine ( IL-8 and TNF-alpha) levels. Neutrophils from peripheral blood of healthy individuals were incubated in the presence and absence of IL-15 ( 12.5 - 250ng/ml) for 18h, at 37 degrees C, under tension of 5% CO2, then infected with Pb18 for 4h and evaluated for fungicidal activity, production of superoxide anion and H2O2, and quantification of cytokines IL-8 and TNF-a in the supernatant. Preincubation of neutrophils with IL-15 induced a significant increase in the fungicidal activity of such cells in a dose-dependent manner. After activation, there was an increase in the production of superoxide anion and H2O2 by these cells, suggesting participation of such metabolites in fungicidal activity. Catalase inhibits fungicidal activity, confirming the role of H2O2 in fungus killing. However, the levels of TNF-alpha and IL-8 were not modified after incubation with IL-15, which suggests that its role is not mediated by those cytokines. Taken together, results showed that IL-15 had a modulatory effect on human neutrophils infected in vitro with a high virulent strain of P. brasiliensis, which was characterized by an increased fungicidal activity mediated by a dependent mechanism of oxidative metabolism.

Interleukin 18 messenger RNA and proIL-18 protein expression in chorioamniotic membranes from pregnant women with preterm prelabor rupture of membranes

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

Amniotic Fluid Interleukin-1 Beta and Interleukin-6, but not Interleukin-8 Correlate with Microbial Invasion of the Amniotic Cavity in Preterm Labor

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

The genetics of hypertension modifies the renal cell replication response induced by experimental diabetes

To investigate whether the genetics of hypertension modifies renal cell responses in experimental diabetes, we studied the renal cell replication and its regulation by two cyclin-dependent kinase (Cdk) inhibitors, p27(Kip1) and p21(Cip1), in prehypertensive spontaneously hypertensive rats (SUR) and their genetically normotensive counterparts, Wistar Kyoto (WKY) rats, with and without streptozotocin-induced diabetes. In diabetic SIIR, the number of proliferating glomerular (0.6 +/- 0.3 positive cells/50 glomeruli) and tubulointerstitial (2.8 +/- 0.6 positive tubulointerstitial cells/50 grid fields) cells assessed by the bromodeoxyuridine technique was significantly (P = 0.0002) lower than in control SIIR (13.2 +/- 1.7 and 48.6 +/- 9.7, respectively) and control (14.0 +/- 1.8 and 63.9 +/- 10.6) and diabetic (14.3 +/- 3.5 and 66.4 +/- 11.5) WKY rats. Proliferating cell nuclear antigen, another marker of cell proliferation, was significantly reduced in replicating glomerular (P = 0.0002) and tubulointerstitial (P < 0.0001) cells in diabetic SHR. In freshly isolated glomeruli, the level of p27(Kip1) detected by Western blotting was significantly higher In diabetic SIIR than in nondiabetic SHR (1.52 +/- 0.14 vs. 1.00 +/- 0.10% of control, P = 0.014). The expression of p21(Cip1) in isolated glomeruli did not differ among the groups of rats. In conclusion, the response of renal cell replication to diabetes differs markedly between prehypertensive SIIR and their WKY control rats. The decreased glomerular cell proliferation in prehypertensive diabetic SIIR is at least partly mediated by a higher expression of the Cdk inhibitor p27(Kip1).

Is urine interleukin-8 level a reliable laboratory test for diagnosing late onset sepsis in premature infants?

The present study is aimed to determine serum and urine interleukin-8 (IL-8) levels in premature infants with late onset sepsis (LOS) and to evaluate if urine IL-8 is a useful test for LOS diagnosis. Fifty-six premature infants admitted to the NICU over 1 year had serum and urine IL-8 determined by ELISA. They were divided into three groups: I definite sepsis, II probable sepsis and III non-infected. Results were expressed as mean or median. Differences between groups were assessed by ANOVA, Kruskal-Wallis ANOVA and Dunns Method. Sensitivity, specificity and positive and negative predictive values were calculated and a receiver operator characteristic curve was constructed to determine serum and urine IL-8 accuracy. There were no differences between groups for birth weight, and gestational and post-natal age. Median serum and urine IL-8 levels were significantly higher in GI and GII: 929 x 906 x 625pg/ml; P=0.024, and 249 x 189 x 42pg/mgCr; P< 0.001. Optimal cut-off point was 625pg/ml for serum IL-8 with 69 sensitivity and 75pg/mgCr for urine IL-8 with 92 sensitivity. IL-8 can be determined in urine from premature infants with LOS and is an accurate and feasible diagnosis method.

Interleukin-6 and procalcitonin in children with sepsis and septic shock

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

Evaluation of TNF-alpha, IL-4, and IL-10 and parasite density in spleen and liver of L. (L.) chagasi naturally infected dogs

Dogs are the main domestic reservoirs of L. (L.) chagasi. Once in the vertebrate host, the parasite can cause visceral leishmaniasis, which can also be transmitted to humans. Cytokines are key elements of the host immune response against Leishmania spp. To investigate whether tumor necrosis factor (TNF)-alpha, interleukin (IL)-4 and IL-10 are associated with pattern infection in dogs, these cytokines were quantified in the spleen and liver of dogs naturally infected with L. (L.) chagasi, with or without clinical manifestations, and their levels were correlated with the parasite load verified in these organs. A total of 40 adult dogs naturally infected with L. (L.) chagasi were assessed, together with 12 uninfected control dogs. Samples from spleen and liver were used to determine the cytokine levels by capture ELISA and for quantifying parasite load by real-time PCR. Statistical analysis was performed using the minimum Chi square method and group means were compared using the Tukey test. TNF-alpha, IL-4 and IL-10 levels in infected dogs were higher than in control groups; the liver was the main cytokine-producing organ during infection. The level of splenic TNF-alpha showed correlation with parasite load and may represent an important marker for infection process evolution, with the participation of IL-10. These results may contribute to a clearer understanding of the immune response in dogs infected with L. (L.) chagasi, which may lead to the development of prophylactic or preventive measures for these animals.

Stress hormones increase cell proliferation and regulates interleukin-6 secretion in human oral squamous cell carcinoma cells

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

Actinobacillus actinomycetemcomitans lipopolysaccharide induces interleukin-6 expression through multiple mitogen-activated protein kinase pathways in periodontal ligament fibroblasts

Actinobacillus actinomycetemcomitans plays a major role in the pathogenesis of aggressive periodontitis. Lipopolysaccharide (LPS) derived from A. actinomycetemcomitans is a key factor in inflammatory cytokine generation within periodontal tissues. In this study, we identify major mitogen-activated protein kinase (MAPK) signaling pathways induced by A. actinomycetemcomitans LPS, Escherichia coli LPS and interleukin-1 beta (IL-1 beta) in a murine periodontal ligament (mPDL) fibroblast cell line. Immunoblot analysis was used to assess the phosphorylated forms of p38, extracellular-regulated kinase (ERK) and c-jun N-terminal kinase (JNK) MAPK following stimulation with A. actinomycetemcomitans LPS, E. coli LPS and IL-1 beta. IL-6 mRNA induction was detected via reverse transcription-polymerase chain reaction, while protein levels were quantified via enzyme-linked immunosorbent assays (ELISA). We utilized biochemical inhibitors of p38, ERK and JNK MAPK to identify the MAPK signaling pathways needed for IL-6 expression. Additional use of stable mPDL cell lines containing dominant negative mutant constructs of MAPK kinase-3 and -6 (MKK-3/6) and p38 null mutant mouse embryonic fibroblast (MEF) cells were used to substantiate the biochemical inhibitor data. Blocking p38 MAPK with SB203580 reduced the induction of IL-6 mRNA by A. actinomycetemcomitans LPS, E. coli LPS and IL-1 beta by > 70%, > 95% and similar to 60%, respectively. IL-6 ELISA indicated that blocking p38 MAPK reduced the IL-6 protein levels induced by A. actinomycetemcomitans LPS, E. coli LPS and IL-1 beta by similar to 60%, similar to 50% and similar to 70%, respectively. All MAPK inhibitors significantly reduced the IL-6 protein levels induced by A. actinomycetemcomitans LPS, E. coli LPS and IL-1 beta whereas only p38 inhibitors consistently reduced the A. actinomycetemcomitans LPS, E. coli LPS and IL-1 beta induction of IL-6 mRNA steady-state levels. The contribution of p38 MAPK LPS-induced IL-6 expression was confirmed using MKK-3/6 dominant negative stable mPDL cell lines. Wild-type and p38 alpha(-/-) MEF cells provided additional evidence to support the role of p38 alpha MAPK in A. actinomycetemcomitans LPS-stimulated IL-6. Our results indicate that induction of IL-6 by E. coli LPS, IL-1 beta and A. actinomycetemcomitans LPS requires signaling through MKK-3-p38 alpha ERK, JNK and p38 MAPK in mPDL cells.

The Short-Term Effectiveness of Non-Surgical Treatment in Reducing Levels of Interleukin-1 beta and Proteases in Gingival Crevicular Fluid From Patients With Type 2 Diabetes Mellitus and Chronic Periodontitis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Antigenic Activity of Bacterial Endodontic Contents from Primary Root Canal Infection with Periapical Lesions against Macrophage in the Release of Interleukin-1 beta and Tumor Necrosis Factor alpha

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

Haplotypes of susceptibility to chronic periodontitis in the Interleukin 8 gene do not influence protein level in the gingival crevicular fluid

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

Tumor Necrosis Factor alpha and Interleukin-1 beta Modulate Calcium and Nitric Oxide Signaling in Mechanically Stimulated Osteocytes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Interleukin-1 beta and Interleukin-6 Expression and Gene Polymorphisms in Subjects with Peri-Implant Disease

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)