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Genetic polymorphism in an inflammasome component, cervical mycoplasma detection and female infertility in women undergoing in vitro fertilization

WITKIN, Steven S.; BIERHALS, Katrin; LINHARES, Iara; NORMAND, Neil; DIETERLE, Stefan; NEUER, Andreas
Fonte: ELSEVIER IRELAND LTD Publicador: ELSEVIER IRELAND LTD
Tipo: Artigo de Revista Científica
Português
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37.19%
The inflammasome is an inducible cytoplasmic structure that is responsible for production and release of biologically active interleukin-1 (IL-1). A polymorphism in the inflammasome component NALP3 has been associated with decreased IL-1 levels and increased occurrence of vaginal Candida infection. We hypothesized that this polymorphism-induced variation would influence susceptibility to infertility. DNA was obtained from 243 women who were undergoing in vitro fertilization (IVF) and tested for a length polymorphism in intron 2 of the gene coding for NALP3 (gene symbol CIAS1). At the conclusion of testing the findings were analyzed in relation to clinical parameters and IVF outcome. The frequency of the 12 unit repeat allele, associated with maximal inflammasome activity, was 62.3% in cases of female infertility vs. 75.6% in cases where only the male partner had a detectable fertility problem (p = 0.0095). Conversely, the frequency of the 7 unit repeat allele was 28.9% in those with a female fertility problem, 17.0% in women with infertile males and 18.4% in idiopathic infertility (p = 0.0124). Among the women who were cervical culture-positive for mycoplasma the frequency of the 7 unit repeat was 53.7% as opposed to 19.5% in those negative for this infection (p < 0.0001). We conclude that the CIAS1 7 unit repeat polymorphism increases the likelihood of mycoplasma infection-associated female infertility. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

NLRP3 inflammasome-mediated neutrophil recruitment and hypernociception depend on leukotriene B4 in a murine model of gout

Amaral, Flavio A.; Costa, Vivian V.; Tavares, Livia D.; Sachs, Daniela; Coelho, Fernanda M.; Fagundes, Caio T.; Soriani, Frederico M.; Silveira, Tatiana N.; Cunha, Larissa D.; Zamboni, Dario S.; Quesniaux, Valerie; Peres, Raphael S.; Cunha, Thiago M.; Cun
Fonte: WILEY-BLACKWELL; MALDEN Publicador: WILEY-BLACKWELL; MALDEN
Tipo: Artigo de Revista Científica
Português
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37.27%
Objective Deposition of monosodium urate monohydrate (MSU) crystals in the joints promotes an intense inflammatory response and joint dysfunction. This study evaluated the role of the NLRP3 inflammasome and 5-lipoxygenase (5-LOX)derived leukotriene B4 (LTB4) in driving tissue inflammation and hypernociception in a murine model of gout. Methods. Gout was induced by injecting MSU crystals into the joints of mice. Wild-type mice and mice deficient in NLRP3, ASC, caspase 1, interleukin-1 beta (IL-1 beta), IL-1 receptor type I (IL-1RI), IL-18R, myeloid differentiation factor 88 (MyD88), or 5-LOX were used. Evaluations were performed to assess neutrophil influx, LTB4 activity, cytokine (IL-1 beta, CXCL1) production (by enzyme-linked immunosorbent assay), synovial microvasculature cell adhesion (by intravital microscopy), and hypernociception. Cleaved caspase 1 and production of reactive oxygen species (ROS) were analyzed in macrophages by Western blotting and fluorometric assay, respectively. Results. Injection of MSU crystals into the knee joints of mice induced neutrophil influx and neutrophildependent hypernociception. MSU crystal-induced neutrophil influx was CXCR2-dependent and relied on the induction of CXCL1 in an NLRP3/ASC/caspase 1/IL-1 beta/MyD88-dependent manner. LTB4 was produced rapidly after injection of MSU crystals...

Polimorphisms in Inflammasome Genes Are Involved in the Predisposition to Systemic Lupus Erythematosus

Pontillo, Alessandra; Girardelli, Martina; Kamada, Anselmo J.; Pancotto, Joao A. T.; Donadi, Eduardo Antonio; Crovella, Sergio; Sandrin-Garcia, Paula
Fonte: INFORMA HEALTHCARE; LONDON Publicador: INFORMA HEALTHCARE; LONDON
Tipo: Artigo de Revista Científica
Português
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37.37%
Recent findings provide evidence of inflammasome critical role in the predisposition to autoimmune disorders. The involvement of inflammasome in the pathogenesis of systemic lupus erythematosus (SLE) has been hypothesized even if no significant association within inflammasome genes mutations or polymorphisms and lupus has been reported yet. We analyzed 14 single nucleotide polymorphisms (SNPs) within 7 inflammasome genes (NLRP1, NLRP3, NLRC4, AIM2, CARD8, CASP1, IL1B) in 144 patients affected by systemic lupus erythematosus and in 158 healthy controls from Southern Brazilian (state of Sao Paulo) with the aim of disclosing the possible role of inflammasome genes in the susceptibility of SLE. Our results demonstrated that NLRP1 rs2670660 SNP and the NLRP1 rs12150220-rs2670660 A-G haplotype were associated with SLE in our study population, and in particular with the development of nephritis, rash and arthritis. These findings are concordant with previously reported association of NLRP1 with vitiligo and type-1 diabetes underlining once more the involvement of NALP1 inflammasome in the pathogenesis of autoimmune disorders.; Sao Paulo Research Foundation (FAPESP); Sao Paulo Research foundation (FAPESP) [09/53575-5]; Brazilian Ministry of Science...

Estudo da participação do inflamassoma NLRP3 na resposta inflamatória induzida pelo fungo dimórfico Paracoccidioides brasiliensis; NLRP3 inflammasome participation in the inflammatory immune response induced by the dimorrphic fungi Paracoccidioides brasiliensis

Lívia Furquim de Castro
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/04/2015 Português
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Diversos estudos demonstram que a resposta inflamatória é de extrema importância para o controle da Paracoccidioidomicose (PCM). Essa resposta inflamatória é iniciada pelo reconhecimento das células fúngicas por receptores expressos por células do sistema imunológico inato. Dentre esses receptores, o NLRP3 foi associado com o reconhecimento de fungos patogênicos em modelos experimentais, atuando em conjunto com o TLR2 e a dectina-1. O NLRP3 atua na formação de um complexo multiproteico denominado inflamassoma, o qual ativa a caspase-1, que é responsável pela produção das formas ativas de duas importantes citocinas inflamatórias: a IL-1? e a IL-18. Esse estudo teve por objetivo investigar o envolvimento do NLRP3 na ativação da resposta inflamatória de macrófagos e células dendríticas humanas (DCs) derivadas de monócitos em resposta ao Paracoccidioides brasiliensis (Pb), além de avaliar a participação do NLRP3 na indução da resposta imunológica adaptativa. Nossos resultados demonstraram que células de lesões de pacientes com PCM (mucosa oral ou linfonodos) apresentam produção de IL-1beta, IL-18 e IL-37 e que macrófagos dessas lesões são positivos para Caspase-1 e NLRP3. Também fomos capazes de demonstrar que o reconhecimento de células leveduriformes por DCs e macrófagos humanos leva à ativação do inflamassoma NLRP3 e consequente produção de IL-1 e IL-18. Esse reconhecimento envolve a participação de receptores de superfície (TLR2 e Dectina-1)...

Inflammasome-mediated regulation of hepatic stellate cells

Watanabe, Azuma; Sohail, Muhammad Adnan; Gomes, Dawidson Assis; Hashmi, Ardeshir; Nagata, Jun; Sutterwala, Fayyaz Shiraz; Mahmood, Shamail; Jhandier, Muhammad Nauman; Shi, Yan; Flavell, Richard Anthony; Mehal, Wajahat Zafar
Fonte: American Physiological Society Publicador: American Physiological Society
Tipo: Artigo de Revista Científica
Português
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27.43%
The inflammasome is a cytoplasmic multiprotein complex that has recently been identified in immune cells as an important sensor of signals released by cellular injury and death. Analogous to immune cells, hepatic stellate cells (HSC) also respond to cellular injury and death. Our aim was to establish whether inflammasome components were present in HSC and could regulate HSC functionality. Monosodium urate (MSU) crystals (100 μg/ml) were used to experimentally induce inflammasome activation in LX-2 and primary mouse HSC. Twenty-four hours later primary mouse HSC were stained with α-smooth muscle actin and visualized by confocal microscopy, and TGF-β and collagen1 mRNA expression was quantified. LX-2 cells were further cultured with or without MSU crystals for 24 h in a transwell chemotaxis assay with PDGF as the chemoattractant. We also examined inhibition of calcium (Ca2+) signaling in LX-2 cells treated with or without MSU crystals using caged inositol 1,4,5-triphosphate (IP3). Finally, we confirmed an important role of the inflammasome in experimental liver fibrosis by the injection of carbon tetrachloride (CCl4) or thioacetamide (TAA) in wild-type mice and mice lacking components of the inflammasome. Components of the inflammasome are expressed in LX-2 cells and primary HSC. MSU crystals induced upregulation of TGF-β and collagen1 mRNA and actin reorganization in HSCs from wild-type mice but not mice lacking inflammasome components. MSU crystals inhibited the release of Ca2+ via IP3 in LX-2 cells and also inhibited PDGF-induced chemotaxis. Mice lacking the inflammasome-sensing and adaptor molecules...

The Pannexin 1 Channel Activates the Inflammasome in Neurons and Astrocytes*

Silverman, William R.; de Rivero Vaccari, Juan Pablo; Locovei, Silviu; Qiu, Feng; Carlsson, Steven K.; Scemes, Eliana; Keane, Robert W.; Dahl, Gerhard
Fonte: American Society for Biochemistry and Molecular Biology Publicador: American Society for Biochemistry and Molecular Biology
Tipo: Artigo de Revista Científica
Português
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27.43%
The inflammasome is a multiprotein complex involved in innate immunity. Activation of the inflammasome causes the processing and release of the cytokines interleukins 1β and 18. In primary macrophages, potassium ion flux and the membrane channel pannexin 1 have been suggested to play roles in inflammasome activation. However, the molecular mechanism(s) governing inflammasome signaling remains poorly defined, and it is undetermined whether these mechanisms apply to the central nervous system. Here we show that high extracellular potassium opens pannexin channels leading to caspase-1 activation in primary neurons and astrocytes. The effect of K+ on pannexin 1 channels was independent of membrane potential, suggesting that stimulation of inflammasome signaling was mediated by an allosteric effect. The activation of the inflammasome by K+ was inhibited by the pannexin 1 channel blocker probenecid, supporting a role of pannexin 1 in inflammasome activation. Co-immunoprecipitation of neuronal lysates indicates that pannexin 1 associates with components of the multiprotein inflammasome complex, including the P2X7 receptor and caspase-1. Moreover antibody neutralization of the adaptor protein ASC (apoptosis-associated speck-like protein containing a CARD) blocked ATP-induced cell death in oocytes co-expressing P2X7 receptor and pannexin 1. Thus...

LRRFIP2 negatively regulates NLRP3 inflammasome activation in macrophages by promoting Flightless-I-mediated caspase-1 inhibition

Jin, Jing; Yu, Qian; Han, Chaofeng; Hu, Xiang; Xu, Sheng; Wang, Qingqing; Wang, Jianli; Li, Nan; Cao, Xuetao
Fonte: Nature Pub. Group Publicador: Nature Pub. Group
Tipo: Artigo de Revista Científica
Publicado em 14/08/2013 Português
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The NLRP3 inflammasome is the most characterized inflammasome activated by cellular infection or stress, which is responsible for the maturation of proinflammatory cytokines IL-1β and IL-18. The precise molecular mechanism for negative regulation of NLRP3 inflammasome activation needs to be further defined. Here we identify leucine-rich repeat Fli-I-interacting protein 2 (LRRFIP2) as an NLRP3-associated protein and an inhibitor for NLRP3 inflammasome activation. LRRFIP2 binds to NLRP3 via its N terminus upon NLRP3 inflammasome activation, and also interacts with Flightless-I, a pseudosubstrate of caspase-1, via its Coil motif. Knockdown of Flightless-I significantly promotes NLRP3 inflammasome activation. LRRFIP2 enhances the interaction between Flightless-I and caspase-1, facilitating the inhibitory effect of Flightless-I on caspase-1 activation. Furthermore, silencing of Flightless-I abrogates the inhibitory effect of LRRFIP2 on NLRP3 inflammasome. These data demonstrate that LRRFIP2 inhibits NLRP3 inflammasome activation by recruiting the caspase-1 inhibitor Flightless-I, thus outlining a new mechanism for negative regulation of NLRP3 inflammasome.

The Inflammasome Mediates Hyperoxia-Induced Alveolar Cell Permeability

Kolliputi, Narasaiah; Shaik, Rahamthulla S.; Waxman, Aaron B.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
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27.43%
A hallmark of hyperoxic acute lung injury is the influx of inflammatory cells to lung tissue and the production of proinflammatory cytokines, such as IL-1β; however, the mechanisms connecting hyperoxia and the inflammatory response to lung damage is not clear. The inflammasome protein complex activates caspase-1 to promote the processing and secretion of proinflammatory cytokines. We hypothesized that hyperoxia-induced K+ efflux activates the inflammasome via the purinergic P2X7 receptor to cause inflammation and hyperoxic acute lung injury. To test this hypothesis, we characterized the expression and activation of inflammasome components in primary murine alveolar macrophages exposed to hyperoxia (95% oxygen and 5% CO2) in vitro, and in alveolar macrophages isolated from mice exposed to hyperoxia (100% oxygen). Our results showed that hyperoxia increased K+ efflux, inflammasome formation, release of proinflammatory cytokines, and induction of caspase-1 and IL-1β cleavage both in vitro and in vivo. The P2X7 agonist ATP enhanced hyperoxia-induced inflammasome activation, whereas the P2X7 antagonist, oxidized ATP, inhibited hyperoxia induced inflammasome activation. In addition, when ATP was scavenged with apyrase, hyperoxia-induced inflammasome activation was significantly decreased. Furthermore...

Mycobacterium tuberculosis and the host cell inflammasome: a complex relationship

Briken, Volker; Ahlbrand, Sarah E.; Shah, Swati
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 09/10/2013 Português
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The production of IL-1β during the infection with Mycobacterium tuberculosis (Mtb) is important for successful host immune defense. In macrophages and dendritic cells the host cell inflammasome is crucial for generation of secreted IL-1β in response to Mtb infections. In these cell types Mtb infection only activates the NLRP3-inflammasome. New reports demonstrate that nitric oxide has an important function in the negative regulation of the NLRP3-inflammasome to reduce tissue damage during Mtb infections. The type I interferon, IFN-β, is induced after Mtb infections and can also suppress NLRP3-inflammasome activation. In contrast, IFN-β increases activity of the AIM2-inflammasome after infection with intracellular pathogens such as Francisella tularensis and Listeria monocytogenes. Recent results demonstrate that non-tuberculous mycobacteria but not virulent Mtb induce the AIM2-inflammasome in an IFN-β dependent matter. Indeed, Mtb inhibits AIM2-inflammasome activation via its ESX-1 secretion system. This novel immune evasion mechanism may help Mtb to allow the induction of low levels of IFN-β to suppress the NLRP3-inflammasome without activating the AIM2-inflammasome.

MicroRNA-133a-1 regulates inflammasome activation through uncoupling protein-2

Bandyopadhyay, Sayantani; Lane, Troy; Venugopal, Rajanbabu; Parthasarathy, Prasanna Tamarapu; Cho, Young; Galam, Lakshmi; Lockey, Richard; Kolliputi, Narasaiah
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
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27.53%
Inflammasomes are multimeric protein complexes involved in the processing of IL-1β through Caspase-1 cleavage. NLRP3 is the most widely studied inflammasome, which has been shown to respond to a large number of both endogenous and exogenous stimuli. Although studies have begun to define basic pathways for the activation of inflammasome and have been instrumental in identifying therapeutics for inflammasome related disorders; understanding the inflammasome activation at the molecular level is still incomplete. Recent functional studies indicate that microRNAs (miRs) regulate molecular pathways and can lead to diseased states when hampered or overexpressed. Mechanisms involving the miRNA regulatory network in the activation of inflammasome and IL-1β processing is yet unknown. This report investigates the involvement of miR-133a-1 in the activation of inflammasome (NLRP3) and IL-1β production. miR-133a-1 is known to target the mitochondrial uncoupling protein 2 (UCP2). The role of UCP2 in inflammasome activation has remained elusive. To understand the role of miR-133a-1 in regulating inflammasome activation, we either overexpressed or suppressed miR-133a-1 in differentiated THP1 cells that express the NLRP3 inflammasome. Levels of Caspase-1 and IL-1β were analyzed by Western blot analysis. For the first time...

ADP-Ribosylation of NLRP3 by Mycoplasma pneumoniae CARDS Toxin Regulates Inflammasome Activity

Bose, Santanu; Segovia, Jesus A.; Somarajan, Sudha R.; Chang, Te-Hung; Kannan, T. R.; Baseman, Joel B.
Fonte: American Society of Microbiology Publicador: American Society of Microbiology
Tipo: Artigo de Revista Científica
Publicado em 23/12/2014 Português
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27.45%
The inflammasome is a major regulator of inflammation through its activation of procaspase-1, which cleaves prointerleukin-1β (pro-IL-1β) into its mature form. IL-1β is a critical proinflammatory cytokine that dictates the severity of inflammation associated with a wide spectrum of inflammatory diseases. NLRP3 is a key component of the inflammasome complex, and multiple signals and stimuli trigger formation of the NLRP3 inflammasome complex. In the current study, we uncovered a yet unknown mechanism of NLRP3 inflammasome activation by a pathogen-derived factor. We show that the unique bacterial ADP-ribosylating and vacuolating toxin produced by Mycoplasma pneumoniae and designated community-acquired respiratory distress syndrome (CARDS) toxin activates the NLRP3 inflammasome by colocalizing with the NLRP3 inflammasome and catalyzing the ADP-ribosylation of NLRP3. Mutant full-length CARDS toxin lacking ADP-ribosyltransferase (ADPRT) activity and truncated CARDS toxins unable to bind to macrophages and be internalized failed to activate the NLRP3 inflammasome. These studies demonstrate that CARDS toxin-mediated ADP-ribosylation constitutes an important posttranslational modification of NLRP3, that ADPRT activity of CARDS toxin is essential for NLRP3 inflammasome activation...

Receptor interacting protein kinase 2-mediated mitophagy regulates inflammasome activation during virus infection

Lupfer, Christopher; Thomas, Paul G.; Anand, Paras K.; Vogel, Peter; Milasta, Sandra; Martinez, Jennifer; Huang, Gonghua; Green, Maggie; Kundu, Mondira; Chi, Hongbo; Xavier, Ramnik J.; Green, Douglas R.; Lamkanfi, Mohamed; Dinarello, Charles A.; Doherty,
Fonte: Harvard University Publicador: Harvard University
Tipo: Artigo de Revista Científica
Português
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37.09%
NOD2 receptor and the cytosolic protein kinase RIPK2 regulate NF-κB and MAP kinase signaling during bacterial infections, but the role of this immune axis during viral infections has not been addressed. We demonstrate that Nod2−/− and Ripk2−/− mice are hypersusceptible to influenza A virus infection. Ripk2−/− cells displayed defective mitophagy leading to enhanced mitochondrial superoxide production and accumulation of damaged mitochondria resulting in increased NLRP3 inflammasome activation and IL-18 production. RIPK2 regulated mitophagy in a kinase-dependent manner by phosphorylating the mitophagy inducer ULK1. Accordingly, Ulk1−/− cells displayed enhanced mitochondrial superoxide production and caspase-1 activation. These results demonstrate a role for NOD2-RIPK2 signaling in protection against virally triggered immunopathology by negatively regulating NLRP3 inflammasome activation and IL-18 production via ULK1-dependent mitophagy.

Role of the NLRP3 inflammasome in the transient release of IL-1β induced by monosodium urate crystals in human fibroblast-like synoviocytes

Zheng, Shu-cong; Zhu, Xiao-xia; Xue, Yu; Zhang, Li-hong; Zou, He-jian; Qiu, Jian-hua; Liu, Qiong
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
Português
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37.19%
Background: To investigate whether monosodium urate (MSU) crystals induce interleukin (IL)-1β in human fibroblast-like synoviocytes (FLS), and whether the NLRP3 inflammasome is involved in the inflammatory mechanism. Methods: Human FLS isolated from explants of synovial tissue were stimulated with MSU crystals (0.001 to 0.5 mg/ml) for different time course (6 hours to 48 hours). The expressions of IL-1β, IL-6, TNF-α and NLRP3 were evaluated with ELISA, Western blot and quantitative real-time PCR. Results: Exposure of FLS to MSU crystals transiently induced a significant increase in IL-1β expression in culture medium with a peak at 6 h. The mRNA level of IL-1β in the FLS cells had a similar pattern at this time point. Changes in IL-6 and TNF-α expression were not observed. Simultaneously, intercellular pro-IL-1β was detected at 6 h. Furthermore, MSU crystals also induced NLRP3 mRNA and protein expression at 6 h to 48 h after MSU treatment. Conclusions: MSU crystals directly increased IL-1β and intercellular NLRP3 expression in FLS cells. It is suggested that the NLRP3 inflammasome may be associated with IL-1β in FLS treated with MSU. Altogether, MSU could induce production and release of IL-1β through the NLRP3 inflammasome in human synoviocytes. Electronic supplementary material The online version of this article (doi:10.1186/s12950-015-0070-7) contains supplementary material...

Caracterizació molecular y funcional de Gbp4 de pez cebra : un nuevo componente del inflamasoma= Molecular and functional chraterization of zebrafish Gbp4: a new inflammasome component

Tyrkalska, Sylwia Dominika
Fonte: Universidade de Múrcia Publicador: Universidade de Múrcia
Tipo: Tese de Doutorado Formato: application/pdf
Português
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27.49%
INTRODUCCIÓN: La señalización a través de los NOD-like receptors (NLRs), que son una familia de receptores citosólicos de reconocimiento de patrones (PRRs), da lugar al procesamiento y activación de las citoquinas pro-inflamatorias IL-1 β e IL-18 mediados por caspasa-1, así como de la inducción de una forma de muerte celular recientemente descrita llamada piroptosis. Para ello, los NLRs median la formación de plataformas multiproteicas de señalización llamadas inflamasomas, que alertan al sistema inmune de la presencia de infección o daño tisular. OBJETIVOS: (1) Establecimiento de un modelo de infección de Salmonella Typhimurium en pez cebra para estudiar la activación, el ensamblaje y el funcionamiento del inflamasoma; (2) Caracterización del papel de la flagelina de S. Typhimurium en el mecanismo de infección en pez cebra; (3) Caracterización del papel de Gbp4 de pez cebra en la activación y ensamblaje del inflamasoma, así como en la eliminación de S. Typhimurium; (4) Caracterización del papel de los neutrófilos en la eliminación de S. Typhimurium dependiente de Gbp4 en pez cebra; (5) Caracterización del papel de Gbp4 en la producción de prostaglandinas dependiente del inflamasoma, y del de las prostaglandinas en la eliminación de S. Typhimurium. METODOLOGÍA: Los métodos utilizados en la tesis doctoral son: Ensayos de infección con S. Typhimurium...

Localisation and functionality of the inflammasome in neutrophils

Joos, Melanie
Fonte: Universität Tübingen Publicador: Universität Tübingen
Tipo: Dissertation; info:eu-repo/semantics/doctoralThesis
Português
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27.49%
The ‘inflammasome’, a multi-protein complex in monocytes and granulocytes, has emerged as playing a key role in innate immunity and inflammation. Regarding monocytes, definite data are available that the inflammasome, localised in the cytosol, controls the maturation of different interleukins via caspase-1 activation. Concerning the situation in neutrophil granulocytes—which was the main focus of our research—little is currently known about the subcellular localisation and the function of the inflammasome. To precisely characterise the localisation of the inflammasome in neutrophils, we utilised subcellular fractionation and detected inflammasomal components not only in the cytoplasm but also in mobile vesicles and granules. These findings may implicate that neutrophils are able to regulate their inflammasomes dynamically between intracellular stores and the cell surface, where they could participate in pathogen recognition and uptake. To gain a better understanding about the function of the inflammasomes in neutrophils, we stimulated highly purified cells with known inflammasome activators. The results of these experiments suggest that inflammasome activation in human neutrophils triggers the IL-1β, but not the IL-18, IL-1α...

IL-27 Enhances LPS-Induced Proinflammatory Responses in Human Monocytes: Augmented Inflammasome Activity and IL-23 Expression

WYNICK, CHRISTOPHER
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
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37.37%
Inflammation plays an important role in responding to injury and combating infections. In this thesis, I examine how inflammation is regulated by cytokines responsible for driving initial immune responses to combat infections. Toll-Like receptor (TLR)-mediated activation of monocytes, macrophages and dendritic cells can lead to the co-expression of proinflammatory cytokines including IL-1β, IL-23, and IL-27. IL-23 and IL-27 belong to the IL-12 cytokine family yet have distinct functions; IL-23, along with IL-1β, regulates TH17 cell differentiation, while IL-27 supports TH1 proliferation and inhibits TH17 differentiation. Our lab has previously demonstrated that IL-27 can modulate inflammasome activation, the multi-protein regulatory complex that produces bioactive IL-1β; however, the mechanism behind this is poorly understood. Similarly, the effect of IL-27 on IL-23 expression has not been well described. Using the CD14+ THP-1 monocytic cell line as a model system, I investigated the role of IL-27 on LPS-mediated inflammasome activation and IL-23 expression. To induce inflammasome activation, CD14+ THP-1 cells were treated with LPS and/or IL-27, followed by treatment with ATP. I demonstrated that IL-27-enhanced inflammasome activation...

HIV-1 induces NALP3-inflammasome expression and interleukin-1 beta secretion in dendritic cells from healthy individuals but not from HIV-positive patients

Pontillo, Alessandra; Silva, Lais T.; Sumida, Telma Miyuki Oshiro; Finazzo, Claudia; Crovella, Sergio; Duarte, Alberto Jose da Silva
Fonte: LIPPINCOTT WILLIAMS & WILKINS; PHILADELPHIA Publicador: LIPPINCOTT WILLIAMS & WILKINS; PHILADELPHIA
Tipo: Artigo de Revista Científica
Português
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37.45%
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...

Differential inflammasome expression and IL-1β secretion in monocyte-derived dendritic cells differentiated with IL-4 or IFN-α

Pontillo, Alessandra; Santillo, Bruna Tereso; Duarte, Alberto Jose da Silva; Sumida, Telma Miyuki Oshiro
Fonte: BioMed Central; Londres Publicador: BioMed Central; Londres
Tipo: Artigo de Revista Científica
Português
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37.32%
NLRP3-inflammasome activation was evaluated in monocyte-derived dendritic cells (DC) obtained through IL-4 (IL4-DC) or IFN-α (IFN-DC) protocols and pulsed with chemically inactivated HIV-1. Inflammasome' genes expression and IL-1β secretion were compared in DC isolated from 15 healthy subjects (HC) and 10 HIV-1 infected individuals (HIV+). FINDINGS: Whether HIV was able to increased NLRP3-inflammasome genes expression and IL-1β secretion in IL4-DC from HC, the induction of inflammasome appeared significantly reduced in IFN-DC from HC, suggesting a different responsive state of IFN-DC compared to IL4-DC. No inflammasome activation was observed in IL4-DC as well as in IFN-DC derived from HIV + subjects, confirming previous findings on "unresponsive" state of DC derived from HIV + possibly due to chronic inflammatory state of these individuals. CONCLUSIONS: Our results showed that IFN-α differently modulates inflammasome expression during monocytes-DC in vitro differentiation. These findings could be of interest considering the on-going research about DC manipulation and therapeutic strategies for HIV + involving DC-based immune-vaccines.; Sao Paulo Research Foundation (FAPESP)

The calcium-sensing receptor regulates the NLRP3 inflammasome through Ca2+ and cAMP

Lee, Geun-Shik; Subramanian, Naeha; Kim, Andrew I.; Aksentijevich, Ivona; Goldbach-Mansky, Raphaela; Sacks, David B.; Germain, Ronald N.; Kastner, Daniel L.; Chae, Jae Jin
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.47%
Mutations in the gene encoding NLRP3 cause a spectrum of autoinflammatory diseases known as the cryopyrin-associated periodic syndromes (CAPS)1. NLRP3 is a key component of one of several distinct cytoplasmic multiprotein complexes (inflammasomes) that mediate the maturation of the proinflammatory cytokine interleukin-1β (IL-1β) by activating caspase-1. Although several models for inflammasome activation, such as K+ efflux2, generation of reactive oxygen species3 and lysosomal destabilization4, have been proposed, the precise molecular mechanism of NLRP3 inflammasome activation, as well as the mechanism by which CAPS-associated mutations activate NLRP3, remain to be elucidated. Here we show that the murine calcium-sensing receptor (CASR) activates the NLRP3 inflammasome, mediated by increased intracellular Ca2+ and decreased cellular cyclic AMP (cAMP). Ca2+ or other CASR agonists activate the NLRP3 inflammasome in the absence of exogenous ATP, whereas knockdown of CASR reduces inflammasome activation in response to known NLRP3 activators. CASR activates the NLRP3 inflammasome through phospholipase C, which catalyses inositol-1,4,5-trisphosphate production and thereby induces release of Ca2+ from endoplasmic reticulum stores. The increased cytoplasmic Ca2+ promotes the assembly of inflammasome components...

Escherichia coli isolates from inflammatory bowel diseases patientssurvive in macrophages and activate NLRP3 inflammasome

Olivares, Mauricio; Quera, Rodrigo; Núñez, Gabriela; Álvares Lobos, Manuel; Golenbock, Douglas; Franchi, Luigi; González Burgos, María Julieta; Díaz Jiménez, David; Hermoso Ramello, Marcela Alejandra; Araya, Daniela; López Kostner, Luis Francisco;
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo de revista
Português
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Artículo de publicación ISI; Crohn’s disease (CD) is a multifactorial pathology associated with the presence of adherent-invasiveEscherichia coli (AIEC) and NLRP3 polymorphic variants. The presence of intracellular E. coli in otherintestinal pathologies (OIP) and the role of NLRP3-inflammasome in the immune response activated bythese bacteria have not been investigated. In this study, we sought to characterize intracellular strainsisolated from patients with CD, ulcerative colitis (UC) and OIP, and analyze NLRP3-inflammasome rolein the immune response and bactericidal activity induced in macrophages exposed to invasive bacteria.For this, intracellular E. coli isolation from ileal biopsies, using gentamicin-protection assay, revealeda prevalence and CFU/biopsy of E. coli higher in biopsies from CD, UC and OIP patients than in con-trols. To characterize bacterial isolates, pulsed-field gel electrophoresis (PFGE) patterns, virulence genes,serogroup and phylogenetic group were analyzed. We found out that bacteria isolated from a given patientwere closely related and shared virulence factors; however, strains from different patients were geneti-cally heterogeneous. AIEC characteristics in isolated strains, such as invasive and replicative properties...